Modality Specific Cerebro-Cerebellar Activations in Verbal Working Memory: An fMRI Study

PubMed Central

Kirschen, Matthew P.; Chen, S. H. Annabel; Desmond, John E.

2010-01-01

Verbal working memory (VWM) engages frontal and temporal/parietal circuits subserving the phonological loop, as well as, superior and inferior cerebellar regions which have projections from these neocortical areas. Different cerebro-cerebellar circuits may be engaged for integrating aurally- and visually-presented information for VWM. The present fMRI study investigated load (2, 4, or 6 letters) and modality (auditory and visual) dependent cerebro-cerebellar VWM activation using a Sternberg task. FMRI revealed modality-independent activations in left frontal (BA 6/9/44), insular, cingulate (BA 32), and bilateral inferior parietal/supramarginal (BA 40) regions, as well as in bilateral superior (HVI) and right inferior (HVIII) cerebellar regions. Visual presentation evoked prominent activations in right superior (HVI/CrusI) cerebellum, bilateral occipital (BA19) and left parietal (BA7/40) cortex while auditory presentation showed robust activations predominately in bilateral temporal regions (BA21/22). In the cerebellum, we noted a visual to auditory emphasis of function progressing from superior to inferior and from lateral to medial regions. These results extend our previous findings of fMRI activation in cerebro-cerebellar networks during VWM, and demonstrate both modality dependent commonalities and differences in activations with increasing memory load. PMID:20714061

Modality specific cerebro-cerebellar activations in verbal working memory: an fMRI study.

PubMed

Kirschen, Matthew P; Chen, S H Annabel; Desmond, John E

2010-01-01

Verbal working memory (VWM) engages frontal and temporal/parietal circuits subserving the phonological loop, as well as, superior and inferior cerebellar regions which have projections from these neocortical areas. Different cerebro-cerebellar circuits may be engaged for integrating aurally- and visually-presented information for VWM. The present fMRI study investigated load (2, 4, or 6 letters) and modality (auditory and visual) dependent cerebro-cerebellar VWM activation using a Sternberg task. FMRI revealed modality-independent activations in left frontal (BA 6/9/44), insular, cingulate (BA 32), and bilateral inferior parietal/supramarginal (BA 40) regions, as well as in bilateral superior (HVI) and right inferior (HVIII) cerebellar regions. Visual presentation evoked prominent activations in right superior (HVI/CrusI) cerebellum, bilateral occipital (BA19) and left parietal (BA7/40) cortex while auditory presentation showed robust activations predominantly in bilateral temporal regions (BA21/22). In the cerebellum, we noted a visual to auditory emphasis of function progressing from superior to inferior and from lateral to medial regions. These results extend our previous findings of fMRI activation in cerebro-cerebellar networks during VWM, and demonstrate both modality dependent commonalities and differences in activations with increasing memory load.

Double Dissociation of Conditioning and Declarative Knowledge Relative to the Amygdala and Hippocampus in Humans

NASA Astrophysics Data System (ADS)

Bechara, Antoine; Tranel, Daniel; Damasio, Hanna; Adolphs, Ralph; Rockland, Charles; Damasio, Antonio R.

1995-08-01

A patient with selective bilateral damage to the amygdala did not acquire conditioned autonomic responses to visual or auditory stimuli but did acquire the declarative facts about which visual or auditory stimuli were paired with the unconditioned stimulus. By contrast, a patient with selective bilateral damage to the hippocampus failed to acquire the facts but did acquire the conditioning. Finally, a patient with bilateral damage to both amygdala and hippocampal formation acquired neither the conditioning nor the facts. These findings demonstrate a double dissociation of conditioning and declarative knowledge relative to the human amygdala and hippocampus.

Visual outcome and impact on quality of life after surgeries differ in children operated for unilateral and bilateral cataract (Pune study 2011)

PubMed Central

Paryani, Mukesh; Khandekar, Rajiv B.; Dole, Kuldeep; Dharmadhikari, Sheetal; Rishikeshi, Nikhil

2012-01-01

Background: We compared vision and quality of life (VQL) of children aged 5-15 years and operated for unilateral and bilateral cataract between 2008 and 2010 in western India. Materials and Methods: In this cohort study, ophthalmologists assessed vision, anterior and posterior segment of eyes with cataract. Children completed a functional vision questionnaire (LVP-FVQ). Follow up at 6 months after surgery included the best corrected visual acuity (BCVA), FVQ and eye assessment. The improvement of BCVA and quality of life were compared in group of unilateral and bilateral cataract. Result: A total of 20 (70%) bilateral and 7 (39%) unilateral cataract were operated within 1 month of detection. All 48 eyes with bilateral cataract were congenital and 12 (67%) unilateral cataract were traumatic. Among bilateral group, 27 eyes [56.2% (95% confidence interval (CI) 44.4-72.2)] and in unilateral group 11 eyes [61.1% (95% CI 38.6-83.6)] had vision ≥ 20/60 at 6 months follow up. The visual gain was significantly higher in children who were operated between 1 month and 1 year of detection (adjusted Odds ratio (OR) = 15.6 P = 0.03). Positive impact on VQL in bilateral group was noted in 50%, 27%, and 13% children for subscale of distant vision, near vision, and field of vision, respectively. There was positive impact in these subscales among children with unilateral cataract. Thirty percent eyes with bilateral cataract and 22% of eyes with unilateral cataract improved their vision. Surgery within 1 month of cataract was significant predictor of improved vision (OR = 16.6 P = 0.02). Conclusion: Vision and VQL improved in children with unilateral and bilateral cataract. However, it was better 6 months following surgery in children with bilateral cataract than in children with unilateral cataract. PMID:23439722

Benefits of interhemispheric integration on the Japanese Kana script-matching tasks.

PubMed

Yoshizaki, K; Tsuji, Y

2000-02-01

We tested Banich's hypothesis that the benefits of bihemispheric processing were enhanced as task complexity increased, when some procedural shortcomings in the previous studies were overcome by using Japanese Kana script-matching tasks. In Exp. 1, the 20 right-handed subjects were given the Physical-Identity task (Katakana-Katakana scripts matching) and the Name-Identity task (Katakana-Hiragana scripts matching). On both tasks, a pair of Kana scripts was tachistoscopically presented in the left, right, and bilateral visual fields. Distractor stimuli were also presented with target Kana scripts on both tasks to equate the processing load between the hemispheres. Analysis showed that, while a bilateral visual-field advantage was found on the name-identity task, a unilateral visual-field advantage was found on the physical-identity task, suggesting that, as the computational complexity of the encoding stage was enhanced, the benefits of bilateral hemispheric processing increased. In Exp. 2, the 16 right-handed subjects were given the same physical-identity task as in Exp. 1, except Hiragana scripts were used as distractors instead of digits to enhance task difficulty. Analysis showed no differences in performance between the unilateral and bilateral visual fields. Taking into account these results of physical-identity tasks for both Exps. 1 and 2, enhancing task demand in the stage of ignoring distractors made the unilateral visual-field advantage obtained in Exp. 1 disappear in Exp. 2. These results supported Banich's hypothesis.

Simultaneous versus Sequential Bilateral Cataract Surgery for Infants with Congenital Cataracts: Visual Outcomes and Economic Costs

PubMed Central

Dave, Hreem; Phoenix, Vidya; Becker, Edmund R.; Lambert, Scott R.

2015-01-01

OBJECTIVES To compare the incidence of adverse events, visual outcomes and economic costs of sequential versus simultaneous bilateral cataract surgery for infants with congenital cataracts. METHODS We retrospectively reviewed the incidence of adverse events, visual outcomes and medical payments associated with simultaneous versus sequential bilateral cataract surgery for infants with congenital cataracts who underwent cataract surgery when 6 months of age or younger at our institution. RESULTS Records were available for 10 children who underwent sequential surgery at a mean age of 49 days for the first eye and 17 children who underwent simultaneous surgery at a mean age of 68 days (p=.25). We found a similar incidence of adverse events between the two treatment groups. Intraoperative or postoperative complications occurred in 14 eyes. The most common postoperative complication was glaucoma. No eyes developed endophthalmitis. The mean absolute interocular difference in logMAR visual acuities between the two treatment groups was 0.47±0.76 for the sequential group and 0.44±0.40 for the simultaneous group (p=.92). Hospital, drugs, supplies and professional payments were on average 21.9% lower per patient in the simultaneous group. CONCLUSIONS Simultaneous bilateral cataract surgery for infants with congenital cataracts was associated with a 21.9% reduction in medical payments and no discernible difference in the incidence of adverse events or visual outcome. PMID:20697007

How sensory-motor systems impact the neural organization for language: direct contrasts between spoken and signed language

PubMed Central

Emmorey, Karen; McCullough, Stephen; Mehta, Sonya; Grabowski, Thomas J.

2014-01-01

To investigate the impact of sensory-motor systems on the neural organization for language, we conducted an H215O-PET study of sign and spoken word production (picture-naming) and an fMRI study of sign and audio-visual spoken language comprehension (detection of a semantically anomalous sentence) with hearing bilinguals who are native users of American Sign Language (ASL) and English. Directly contrasting speech and sign production revealed greater activation in bilateral parietal cortex for signing, while speaking resulted in greater activation in bilateral superior temporal cortex (STC) and right frontal cortex, likely reflecting auditory feedback control. Surprisingly, the language production contrast revealed a relative increase in activation in bilateral occipital cortex for speaking. We speculate that greater activation in visual cortex for speaking may actually reflect cortical attenuation when signing, which functions to distinguish self-produced from externally generated visual input. Directly contrasting speech and sign comprehension revealed greater activation in bilateral STC for speech and greater activation in bilateral occipital-temporal cortex for sign. Sign comprehension, like sign production, engaged bilateral parietal cortex to a greater extent than spoken language. We hypothesize that posterior parietal activation in part reflects processing related to spatial classifier constructions in ASL and that anterior parietal activation may reflect covert imitation that functions as a predictive model during sign comprehension. The conjunction analysis for comprehension revealed that both speech and sign bilaterally engaged the inferior frontal gyrus (with more extensive activation on the left) and the superior temporal sulcus, suggesting an invariant bilateral perisylvian language system. We conclude that surface level differences between sign and spoken languages should not be dismissed and are critical for understanding the neurobiology of language. PMID:24904497

Bilateral Symmetry of Visual Function Loss in Cone-Rod Dystrophies.

PubMed

Galli-Resta, Lucia; Falsini, Benedetto; Rossi, Giuseppe; Piccardi, Marco; Ziccardi, Lucia; Fadda, Antonello; Minnella, Angelo; Marangoni, Dario; Placidi, Giorgio; Campagna, Francesca; Abed, Edoardo; Bertelli, Matteo; Zuntini, Monia; Resta, Giovanni

2016-07-01

To investigate bilateral symmetry of visual impairment in cone-rod dystrophy (CRD) patients and understand the feasibility of clinical trial designs treating one eye and using the untreated eye as an internal control. This was a retrospective study of visual function loss measures in 436 CRD patients followed at the Ophthalmology Department of the Catholic University in Rome. Clinical measures considered were best-corrected visual acuity, focal macular cone electroretinogram (fERG), and Ganzfeld cone-mediated and rod-mediated electroretinograms. Interocular agreement in each of these clinical indexes was assessed by t- and Wilcoxon tests for paired samples, structural (Deming) regression analysis, and intraclass correlation. Baseline and follow-up measures were analyzed. A separate analysis was performed on the subset of 61 CRD patients carrying likely disease-causing mutations in the ABCA4 gene. Statistical tests show a very high degree of bilateral symmetry in the extent and progression of visual impairment in the fellow eyes of CRD patients. These data contribute to a better understanding of CRDs and support the feasibility of clinical trial designs involving unilateral eye treatment with the use of fellow eye as internal control.

Behavioral evidence for inter-hemispheric cooperation during a lexical decision task: a divided visual field experiment.

PubMed

Perrone-Bertolotti, Marcela; Lemonnier, Sophie; Baciu, Monica

2013-01-01

HIGHLIGHTSThe redundant bilateral visual presentation of verbal stimuli decreases asymmetry and increases the cooperation between the two hemispheres.The increased cooperation between the hemispheres is related to semantic information during lexical processing.The inter-hemispheric interaction is represented by both inhibition and cooperation. This study explores inter-hemispheric interaction (IHI) during a lexical decision task by using a behavioral approach, the bilateral presentation of stimuli within a divided visual field experiment. Previous studies have shown that compared to unilateral presentation, the bilateral redundant (BR) presentation decreases the inter-hemispheric asymmetry and facilitates the cooperation between hemispheres. However, it is still poorly understood which type of information facilitates this cooperation. In the present study, verbal stimuli were presented unilaterally (left or right visual hemi-field successively) and bilaterally (left and right visual hemi-field simultaneously). Moreover, during the bilateral presentation of stimuli, we manipulated the relationship between target and distractors in order to specify the type of information which modulates the IHI. Thus, three types of information were manipulated: perceptual, semantic, and decisional, respectively named pre-lexical, lexical and post-lexical processing. Our results revealed left hemisphere (LH) lateralization during the lexical decision task. In terms of inter-hemisphere interaction, the perceptual and decision-making information increased the inter-hemispheric asymmetry, suggesting the inhibition of one hemisphere upon the other. In contrast, semantic information decreased the inter-hemispheric asymmetry, suggesting cooperation between the hemispheres. We discussed our results according to current models of IHI and concluded that cerebral hemispheres interact and communicate according to various excitatory and inhibitory mechanisms, all which depend on specific processes and various levels of word processing.

Behavioral evidence for inter-hemispheric cooperation during a lexical decision task: a divided visual field experiment

PubMed Central

Perrone-Bertolotti, Marcela; Lemonnier, Sophie; Baciu, Monica

2013-01-01

HIGHLIGHTS The redundant bilateral visual presentation of verbal stimuli decreases asymmetry and increases the cooperation between the two hemispheres.The increased cooperation between the hemispheres is related to semantic information during lexical processing.The inter-hemispheric interaction is represented by both inhibition and cooperation. This study explores inter-hemispheric interaction (IHI) during a lexical decision task by using a behavioral approach, the bilateral presentation of stimuli within a divided visual field experiment. Previous studies have shown that compared to unilateral presentation, the bilateral redundant (BR) presentation decreases the inter-hemispheric asymmetry and facilitates the cooperation between hemispheres. However, it is still poorly understood which type of information facilitates this cooperation. In the present study, verbal stimuli were presented unilaterally (left or right visual hemi-field successively) and bilaterally (left and right visual hemi-field simultaneously). Moreover, during the bilateral presentation of stimuli, we manipulated the relationship between target and distractors in order to specify the type of information which modulates the IHI. Thus, three types of information were manipulated: perceptual, semantic, and decisional, respectively named pre-lexical, lexical and post-lexical processing. Our results revealed left hemisphere (LH) lateralization during the lexical decision task. In terms of inter-hemisphere interaction, the perceptual and decision-making information increased the inter-hemispheric asymmetry, suggesting the inhibition of one hemisphere upon the other. In contrast, semantic information decreased the inter-hemispheric asymmetry, suggesting cooperation between the hemispheres. We discussed our results according to current models of IHI and concluded that cerebral hemispheres interact and communicate according to various excitatory and inhibitory mechanisms, all which depend on specific processes and various levels of word processing. PMID:23818879

Patient-reported utilities in bilateral visual impairment from amblyopia and age-related macular degeneration.

PubMed

van de Graaf, Elizabeth S; Despriet, Dominiek D G; Klaver, Caroline C W; Simonsz, Huibert J

2016-05-17

Utility of visual impairment caused by amblyopia is important for the cost-effectiveness of screening for amblyopia (lazy eye, prevalence 3-3.5 %). We previously measured decrease of utility in 35-year-old persons with unilateral persistent amblyopia. The current observational case-control study aimed to measure loss of utility in patients with amblyopia with recent decrease of vision in their better eye. As these patients are rare, the sample was supplemented by patients with bilateral age-related macular degeneration with similar decrease of vision. From our out-patient department, two groups of patients with recent deterioration to bilateral visual acuity less than Snellen 0.5 (bilateral visual impairment, BVI) were recruited, with either persistent amblyopia and age-related macular degeneration (AMB + AMD), or with bilateral age-related macular degeneration (BAMD). To measure utility, the time trade-off method and the standard gamble method were applied through interviews. Correlations were sought between utility values and visual acuity, age and Visual Function Questionnaire-25 scores. Seventeen AMB + AMD patients (mean age 72.9 years), and 63 BAMD patients (mean age 79.6 years) were included in the study. Among AMB + AMD, 80 % were willing to trade lifetime in exchange for cure. The overall mean time trade-off utility was 0.925. Among BAMD, 75 % were willing to trade, utility was 0.917. Among AMB + AMD, 38 % accepted risk of death in exchange for cure, overall mean standard gamble utility was 0.999. Among BAMD, 49 % accepted risk of death, utility was 0.998. Utility was not related to visual acuity but it was to age (p = 0.02). Elderly patients with BVI, caused by persistent amblyopia and age-related macular degeneration (AMD) or by bilateral AMD, had an approximately 8 % loss of TTO utility. Notably, the 8 % loss in elderly with BVI differs little from the 3.7 % loss we found previously in 35-year-old persons with unilateral amblyopia with good vision in the other eye. The moderate impact of BVI in senescence could be explained by adaptation, comorbidity, avoidance of risk and a changed percept of cure.

Modality specificity in the cerebro-cerebellar neurocircuitry during working memory.

PubMed

Ng, H B Tommy; Kao, K-L Cathy; Chan, Y C; Chew, Effie; Chuang, K H; Chen, S H Annabel

2016-05-15

Previous studies have suggested cerebro-cerebellar circuitry in working memory. The present fMRI study aims to distinguish differential cerebro-cerebellar activation patterns in verbal and visual working memory, and employs a quantitative analysis to deterimine lateralization of the activation patterns observed. Consistent with Chen and Desmond (2005a,b) predictions, verbal working memory activated a cerebro-cerebellar circuitry that comprised left-lateralized language-related brain regions including the inferior frontal and posterior parietal areas, and subcortically, right-lateralized superior (lobule VI) and inferior cerebellar (lobule VIIIA/VIIB) areas. In contrast, a distributed network of bilateral inferior frontal and inferior temporal areas, and bilateral superior (lobule VI) and inferior (lobule VIIB) cerebellar areas, was recruited during visual working memory. Results of the study verified that a distinct cross cerebro-cerebellar circuitry underlies verbal working memory. However, a neural circuitry involving specialized brain areas in bilateral neocortical and bilateral cerebellar hemispheres subserving visual working memory is observed. Findings are discussed in the light of current models of working memory and data from related neuroimaging studies. Copyright © 2016 Elsevier B.V. All rights reserved.

Visual recognition and visually guided action after early bilateral lesion of occipital cortex: a behavioral study of a 4.6-year-old girl.

PubMed

Amicuzi, Ileana; Stortini, Massimo; Petrarca, Maurizio; Di Giulio, Paola; Di Rosa, Giuseppe; Fariello, Giuseppe; Longo, Daniela; Cannatà, Vittorio; Genovese, Elisabetta; Castelli, Enrico

2006-10-01

We report the case of a 4.6-year-old girl born pre-term with early bilateral occipital damage. It was revealed that the child had non-severely impaired basic visual abilities and ocular motility, a selective perceptual deficit of figure-ground segregation, impaired visual recognition and abnormal navigating through space. Even if the child's visual functioning was not optimal, this was the expression of adaptive anatomic and functional brain modifications that occurred following the early lesion. Anatomic brain structure was studied with anatomic MRI and Diffusor Tensor Imaging (DTI)-MRI. This behavioral study may provide an important contribution to understanding the impact of an early lesion of the visual system on the development of visual functions and on the immature brain's potential for reorganisation related to when the damage occurred.

Simultaneous vs sequential bilateral cataract surgery for infants with congenital cataracts: Visual outcomes, adverse events, and economic costs.

PubMed

Dave, Hreem; Phoenix, Vidya; Becker, Edmund R; Lambert, Scott R

2010-08-01

To compare the incidence of adverse events and visual outcomes and to compare the economic costs of sequential vs simultaneous bilateral cataract surgery for infants with congenital cataracts. Retrospective review of simultaneous vs sequential bilateral cataract surgery for infants with congenital cataracts who underwent cataract surgery when 6 months or younger at our institution. Records were available for 10 children who underwent sequential surgery at a mean age of 49 days for the first eye and 17 children who underwent simultaneous surgery at a mean age of 68 days (P = .25). We found a similar incidence of adverse events between the 2 treatment groups. Intraoperative or postoperative complications occurred in 14 eyes. The most common postoperative complication was glaucoma. No eyes developed endophthalmitis. The mean (SD) absolute interocular difference in logMAR visual acuities between the 2 treatment groups was 0.47 (0.76) for the sequential group and 0.44 (0.40) for the simultaneous group (P = .92). Payments for the hospital, drugs, supplies, and professional services were on average 21.9% lower per patient in the simultaneous group. Simultaneous bilateral cataract surgery for infants with congenital cataracts is associated with a 21.9% reduction in medical payments and no discernible difference in the incidence of adverse events or visual outcomes. However, our small sample size limits our ability to make meaningful comparisons of the relative risks and visual benefits of the 2 procedures.

Chronic optic disc swelling overlooked in a diabetic patient with a devastating outcome

PubMed Central

Braithwaite, Tasanee; Plant, Gordon T

2010-01-01

We present a case of asymmetrical but bilateral, progressive, painless visual deterioration over 5 years to no perception of light, in a 61-year-old male diabetic patient referred for a second opinion. The patient had a chronic history of bilateral diabetic maculopathy and unexplained swelling of the optic discs. He was diagnosed with optic atrophy secondary to pseudotumour cerebri (termed idiopathic intracranial hypertension when underlying causes have been excluded), which was associated with obstructive sleep apnoea. The case highlights the critical importance of identifying and investigating chronic papilloedema for reversible causes; the sometimes subtle presentation of pseudotumour cerebri; and the vital role of visual field testing and diagnostic lumbar puncture for timely diagnosis. It also reminds us that chronic bilateral optic disc swelling is not a normal feature of diabetic eye disease, and that alarm bells should sound if reduced visual acuity seems disproportionate to the degree of maculopathy. PMID:22442651

The relation of object naming and other visual speech production tasks: a large scale voxel-based morphometric study.

PubMed

Lau, Johnny King L; Humphreys, Glyn W; Douis, Hassan; Balani, Alex; Bickerton, Wai-Ling; Rotshtein, Pia

2015-01-01

We report a lesion-symptom mapping analysis of visual speech production deficits in a large group (280) of stroke patients at the sub-acute stage (<120 days post-stroke). Performance on object naming was evaluated alongside three other tests of visual speech production, namely sentence production to a picture, sentence reading and nonword reading. A principal component analysis was performed on all these tests' scores and revealed a 'shared' component that loaded across all the visual speech production tasks and a 'unique' component that isolated object naming from the other three tasks. Regions for the shared component were observed in the left fronto-temporal cortices, fusiform gyrus and bilateral visual cortices. Lesions in these regions linked to both poor object naming and impairment in general visual-speech production. On the other hand, the unique naming component was potentially associated with the bilateral anterior temporal poles, hippocampus and cerebellar areas. This is in line with the models proposing that object naming relies on a left-lateralised language dominant system that interacts with a bilateral anterior temporal network. Neuropsychological deficits in object naming can reflect both the increased demands specific to the task and the more general difficulties in language processing.

Bilateral implantation of +2.5 D multifocal intraocular lens and contralateral implantation of +2.5 D and +3.0 D multifocal intraocular lenses: Clinical outcomes.

PubMed

Nuijts, Rudy M M A; Jonker, Soraya M R; Kaufer, Robert A; Lapid-Gortzak, Ruth; Mendicute, Javier; Martinez, Cristina Peris; Schmickler, Stefanie; Kohnen, Thomas

2016-02-01

To assess the clinical visual outcomes of bilateral implantation of Restor +2.5 diopter (D) multifocal intraocular lenses (IOLs) and contralateral implantation of a Restor +2.5 D multifocal IOL in the dominant eye and Restor +3.0 D multifocal IOL in the fellow eye. Multicenter study at 8 investigative sites. Prospective randomized parallel-group patient-masked 2-arm study. This study comprised adults requiring bilateral cataract extraction followed by multifocal IOL implantation. The primary endpoint was corrected intermediate visual acuity (CIVA) at 60 cm, and the secondary endpoint was corrected near visual acuity (CNVA) at 40 cm. Both endpoints were measured 3 months after implantation with a noninferiority margin of Δ = 0.1 logMAR. In total, 103 patients completed the study (53 bilateral, 50 contralateral). At 3 months, the mean CIVA at 60 cm was 0.13 logMAR and 0.10 logMAR in the bilateral group and contralateral group, respectively (difference 0.04 logMAR), achieving noninferiority. Noninferiority was not attained for CNVA at 40 cm; mean values at 3 months for bilateral and contralateral implantation were 0.26 logMAR and 0.11 logMAR, respectively (difference 0.15 logMAR). Binocular defocus curves suggested similar performance in distance vision between the 2 groups. Treatment-emergent ocular adverse events rates were similar between the groups. Bilateral implantation of the +2.5 D multifocal IOL resulted in similar distance as contralateral implantation of the +2.5 D multifocal IOL and +3.0 D multifocal IOL for intermediate vision (60 cm), while noninferiority was not achieved for near distances (40 cm). Copyright © 2016 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Electroretinography and Visual Evoked Potentials in Childhood Brain Tumor Survivors.

PubMed

Pietilä, Sari; Lenko, Hanna L; Oja, Sakari; Koivisto, Anna-Maija; Pietilä, Timo; Mäkipernaa, Anne

2016-07-01

This population-based cross-sectional study evaluates the clinical value of electroretinography and visual evoked potentials in childhood brain tumor survivors. A flash electroretinography and a checkerboard reversal pattern visual evoked potential (or alternatively a flash visual evoked potential) were done for 51 survivors (age 3.8-28.7 years) after a mean follow-up time of 7.6 (1.5-15.1) years. Abnormal electroretinography was obtained in 1 case, bilaterally delayed abnormal visual evoked potentials in 22/51 (43%) cases. Nine of 25 patients with infratentorial tumor location, and altogether 12 out of 31 (39%) patients who did not have tumors involving the visual pathways, had abnormal visual evoked potentials. Abnormal electroretinographies are rarely observed, but abnormal visual evoked potentials are common even without evident anatomic lesions in the visual pathway. Bilateral changes suggest a general and possibly multifactorial toxic/adverse effect on the visual pathway. Electroretinography and visual evoked potential may have clinical and scientific value while evaluating long-term effects of childhood brain tumors and tumor treatment. © The Author(s) 2016.

Bilateral macular edema in a patient treated with tamoxifen: a case report and review of the literature.

PubMed

Zafeiropoulos, Paraskevas; Nanos, Panagiotis; Tsigkoulis, Evangelos; Stefaniotou, Maria

2014-01-01

We present a case of a 41-year-old female patient with progressive bilateral visual loss. On examination, her best corrected visual acuity (BCVA) in her right eye was 3/10 and her BCVA in her left eye was 2/10. Fundus and optical coherence tomography examination revealed severe bilateral macular edema. She had been diagnosed with breast cancer 6 years ago and was receiving tamoxifen at a dosage of 20 mg/day ever since. Tamoxifen therapy was discontinued, and the patient received 250 mg of acetazolamide three times a day for a period of 1 month. Both foveae regained their normal contour within 2 months, and her vision was restored to 10/10 BCVA 3 months later. To our knowledge, this is the first case reported where bilateral intraretinal macular edema is the only retinal manifestation in a patient on oral tamoxifen.

Massive Bilateral Serous Retinal Detachment in a Case of Hypertensive Chorioretinopathy

PubMed Central

Villalba-Pinto, Luis; Hernández-Ortega, M. Ángeles; de los Mozos, F. Javier Lavid; Pascual-Camps, Isabel; Dolz-Marco, Rosa; Arevalo, J. Fernando; Gallego-Pinazo, Roberto

2014-01-01

Introduction Systemic high blood pressure is related to a variety of retinal manifestations. We present an atypical case of hypertensive chorioretinopathy with massive bilateral serous retinal detachment. Case Report A 26-year-old male with a genitourinary malformation and secondary grade IV chronic kidney failure as well as high blood pressure complained of acute vision loss. Dilated fundus examination evidenced a bilateral serous retinal detachment with macular involvement. The patient was unresponsive to oral antihypertensive therapy and dialysis treatment. The serous retinal detachment progressively decreased after the restoration of dialysis and antihypertensive therapy. The final visual acuity was 0.50 in both eyes. Discussion In cases of serous macular detachment, it is mandatory to rule out different systemic and ocular diseases. The presence of uncontrolled high blood pressure may produce aggressive bilateral retinal changes, thus hypertension must be under early and strict control in order to improve the visual outcomes. PMID:25120474

Bilateral ophthalmic artery occlusion in rhino-orbito-cerebral mucormycosis.

PubMed

Song, Yoo Mi; Shin, Sun Young

2008-03-01

To report a case of bilateral ophthalmic artery occlusion in rhino-orbito-cerebral mucormycosis. Reviewed clinical charts, photographs, and fluorescein angiography An 89-year-old man with poorly controlled diabetes developed sudden bilateral ptosis, complete ophthalmoplegia of the right eye, and superior rectus palsy of the left eye. Brain and orbit magnetic resonance imaging showed midbrain infarction and mild diffuse sinusitis. On the 2nd day of hospitalization, sudden visual loss and light reflex loss developed. There were retinal whitening, absence of retinal arterial filling, and a total lack of choroidal perfusion on fluorescein angiography of the right eye. The left eye showed a cherry red spot in the retina and the absence of retinal arterial filling and partial choroidal perfusion on fluorescein angiography. On rhinologic examination, mucormyosis was noticed. Despite treatment, visual acuity and light reflex did not recover and he died 4 days after admission. Bilateral ophthalmic artery occlusion can occur in rhino-orbital-cerebral mucormycosis.

Fibrovascular tissue in bilateral juxtafoveal telangiectasis.

PubMed

Park, D; Schatz, H; McDonald, H R; Johnson, R N

1996-09-01

To study the natural history and retinal findings associated with the intraretinal and subretinal fibrovascular tissues that develop in the late phases of bilateral juxtafoveal telangiectasis. The records of 10 patients (11 eyes) with bilateral juxtafoveal telangiectasis who developed these fibrovascular tissues were examined. Throughout the follow-up period (average 44 months), only 2 eyes (18%) lost 2 or more lines of vision; the final visual acuities were similar for the eyes both with and without fibrovascular tissues. Sixty-four percent of fibrovascular tissues showed little to no growth. Eyes with fibrovascular tissue commonly had retinal pigment epithelial hyperplasia (72%), draining retinal venules (82%), and retinal vascular distortion (64%). Fibrovascular tissues of bilateral juxtafoveal telangiectasis have little proliferative potential and minimal effects on visual acuity. Nevertheless, these fibrovascular tissues do remodel over time, leading to retinal vascular distortion. Given these benign findings, the role of laser photocoagulation treatment of these tissues is questionable.

Visual navigation in adolescents with early periventricular lesions: knowing where, but not getting there.

PubMed

Pavlova, Marina; Sokolov, Alexander; Krägeloh-Mann, Ingeborg

2007-02-01

Visual navigation in familiar and unfamiliar surroundings is an essential ingredient of adaptive daily life behavior. Recent brain imaging work helps to recognize that establishing connectivity between brain regions is of importance for successful navigation. Here, we ask whether the ability to navigate is impaired in adolescents who were born premature and suffer congenital bilateral periventricular brain damage that might affect the pathways interconnecting subcortical structures with cortex. Performance on a set of visual labyrinth tasks was significantly worse in patients with periventricular leukomalacia (PVL) as compared with premature-born controls without lesions and term-born adolescents. The ability for visual navigation inversely relates to the severity of motor disability, leg-dominated bilateral spastic cerebral palsy. This agrees with the view that navigation ability substantially improves with practice and might be compromised in individuals with restrictions in active spatial exploration. Visual navigation is negatively linked to the volumetric extent of lesions over the right parietal and frontal periventricular regions. Whereas impairments of visual processing of point-light biological motion are associated in patients with PVL with bilateral parietal periventricular lesions, navigation ability is specifically linked to the frontal lesions in the right hemisphere. We suggest that more anterior periventricular lesions impair the interrelations between the right hippocampus and cortical areas leading to disintegration of neural networks engaged in visual navigation. For the first time, we show that the severity of right frontal periventricular damage and leg-dominated motor disorders can serve as independent predictors of the visual navigation disability.

Lateralization of spatial rather than temporal attention underlies the left hemifield advantage in rapid serial visual presentation.

PubMed

Asanowicz, Dariusz; Kruse, Lena; Śmigasiewicz, Kamila; Verleger, Rolf

2017-11-01

In bilateral rapid serial visual presentation (RSVP), the second of two targets, T1 and T2, is better identified in the left visual field (LVF) than in the right visual field (RVF). This LVF advantage may reflect hemispheric asymmetry in temporal attention or/and in spatial orienting of attention. Participants performed two tasks: the "standard" bilateral RSVP task (Exp.1) and its unilateral variant (Exp.1 & 2). In the bilateral task, spatial location was uncertain, thus target identification involved stimulus-driven spatial orienting. In the unilateral task, the targets were presented block-wise in the LVF or RVF only, such that no spatial orienting was needed for target identification. Temporal attention was manipulated in both tasks by varying the T1-T2 lag. The results showed that the LVF advantage disappeared when involvement of stimulus-driven spatial orienting was eliminated, whereas the manipulation of temporal attention had no effect on the asymmetry. In conclusion, the results do not support the hypothesis of hemispheric asymmetry in temporal attention, and provide further evidence that the LVF advantage reflects right hemisphere predominance in stimulus-driven orienting of spatial attention. These conclusions fit evidence that temporal attention is implemented by bilateral parietal areas and spatial attention by the right-lateralized ventral frontoparietal network. Copyright © 2017 Elsevier Inc. All rights reserved.

Gamma-oscillations modulated by picture naming and word reading: Intracranial recording in epileptic patients

PubMed Central

Wu, Helen C.; Nagasawa, Tetsuro; Brown, Erik C.; Juhasz, Csaba; Rothermel, Robert; Hoechstetter, Karsten; Shah, Aashit; Mittal, Sandeep; Fuerst, Darren; Sood, Sandeep; Asano, Eishi

2011-01-01

Objective We measured cortical gamma-oscillations in response to visual-language tasks consisting of picture naming and word reading in an effort to better understand human visual-language pathways. Methods We studied six patients with focal epilepsy who underwent extraoperative electrocorticography (ECoG) recording. Patients were asked to overtly name images presented sequentially in the picture naming task and to overtly read written words in the reading task. Results Both tasks commonly elicited gamma-augmentation (maximally at 80–100 Hz) on ECoG in the occipital, inferior-occipital-temporal and inferior-Rolandic areas, bilaterally. Picture naming, compared to reading task, elicited greater gamma-augmentation in portions of pre-motor areas as well as occipital and inferior-occipital-temporal areas, bilaterally. In contrast, word reading elicited greater gamma-augmentation in portions of bilateral occipital, left occipital-temporal and left superior-posterior-parietal areas. Gamma-attenuation was elicited by both tasks in portions of posterior cingulate and ventral premotor-prefrontal areas bilaterally. The number of letters in a presented word was positively correlated to the degree of gamma-augmentation in the medial occipital areas. Conclusions Gamma-augmentation measured on ECoG identified cortical areas commonly and differentially involved in picture naming and reading tasks. Longer words may activate the primary visual cortex for the more peripheral field. Significance The present study increases our understanding of the visual-language pathways. PMID:21498109

Visual and analytical strategies in spatial visualisation: perspectives from bilateral symmetry and reflection

NASA Astrophysics Data System (ADS)

Ramful, Ajay; Ho, Siew Yin; Lowrie, Tom

2015-12-01

This inquiry presents two fine-grained case studies of students demonstrating different levels of cognitive functioning in relation to bilateral symmetry and reflection. The two students were asked to solve four sets of tasks and articulate their reasoning in task-based interviews. The first participant, Brittany, focused essentially on three criteria, namely (1) equidistance, (2) congruence of sides and (3) `exactly opposite' as the intuitive counterpart of perpendicularity for performing reflection. On the other hand, the second participant, Sara, focused on perpendicularity and equidistance, as is the normative procedure. Brittany's inadequate knowledge of reflection shaped her actions and served as a validation for her solutions. Intuitively, her visual strategies took over as a fallback measure to maintain congruence of sides in the absence of a formal notion of perpendicularity. In this paper, we address some of the well-known constraints that students encounter in dealing with bilateral symmetry and reflection, particularly situations involving inclined line of symmetry. Importantly, we make an attempt to show how visual and analytical strategies interact in the production of a reflected image. Our findings highlight the necessity to give more explicit attention to the notion of perpendicularity in bilateral symmetry and reflection tasks.

Multimodal imaging of bilateral diffuse uveal melanocytic proliferation associated with an iris mass lesion.

PubMed

Naysan, Jonathan; Pang, Claudine E; Klein, Robert W; Freund, K Bailey

2016-01-01

Bilateral diffuse uveal melanocytic proliferation (BDUMP) is a rare, paraneoplastic syndrome characterized by bilateral painless visual loss and proliferation of choroidal melanocytes in association with an underlying systemic malignancy. We report a case of bilateral diffuse uveal melanocytic proliferation associated with an underlying gynecological malignancy that also features the infrequent finding of an iris mass lesion, using multimodal imaging including ultra-widefield imaging, spectral domain and swept-source optical coherence tomography. A 59-year-old white female with a prior history of gynecological malignancy in remission presented with progressive bilateral visual loss over several weeks. The patient was noted to have a focal iris mass lesion in her right eye. Ultra-widefield color fundus photography showed a characteristic bilateral 'giraffe pattern' of pigmentary changes extending into the periphery as well as multiple discrete deeply pigmented lesions. Ultra-widefield autofluorescence was useful for visualizing the full extent of involvement. Indocyanine green angiography helped to demarcate the discrete pigmented choroidal lesions. Swept-source OCT clearly delineated the alternating zones of retinal pigment epithelium (RPE) thickening and RPE loss, as well as the prominent choroidal infiltration and thickening. BDUMP is an important diagnosis to consider in the presence of multiple discrete melanocytic choroidal lesions, diffuse choroidal thickening, characteristic RPE changes, iris mass lesions and exudative retinal detachment. Ultra-widefield imaging may demonstrate more extensive lesions than that detected on clinical examination or standard field imaging. Imaging with SS-OCT shows choroidal and RPE characteristics that correlate well with known histopathology of this entity.

The compensatory dynamic of inter-hemispheric interactions in visuospatial attention revealed using rTMS and fMRI.

PubMed

Plow, Ela B; Cattaneo, Zaira; Carlson, Thomas A; Alvarez, George A; Pascual-Leone, Alvaro; Battelli, Lorella

2014-01-01

A balance of mutual tonic inhibition between bi-hemispheric posterior parietal cortices is believed to play an important role in bilateral visual attention. However, experimental support for this notion has been mainly drawn from clinical models of unilateral damage. We have previously shown that low-frequency repetitive TMS (rTMS) over the intraparietal sulcus (IPS) generates a contralateral attentional deficit in bilateral visual tracking. Here, we used functional magnetic resonance imaging (fMRI) to study whether rTMS temporarily disrupts the inter-hemispheric balance between bilateral IPS in visual attention. Following application of 1 Hz rTMS over the left IPS, subjects performed a bilateral visual tracking task while their brain activity was recorded using fMRI. Behaviorally, tracking accuracy was reduced immediately following rTMS. Areas ventro-lateral to left IPS, including inferior parietal lobule (IPL), lateral IPS (LIPS), and middle occipital gyrus (MoG), showed decreased activity following rTMS, while dorsomedial areas, such as Superior Parietal Lobule (SPL), Superior occipital gyrus (SoG), and lingual gyrus, as well as middle temporal areas (MT+), showed higher activity. The brain activity of the homologues of these regions in the un-stimulated, right hemisphere was reversed. Interestingly, the evolution of network-wide activation related to attentional behavior following rTMS showed that activation of most occipital synergists adaptively compensated for contralateral and ipsilateral decrement after rTMS, while activation of parietal synergists, and SoG remained competing. This pattern of ipsilateral and contralateral activations empirically supports the hypothesized loss of inter-hemispheric balance that underlies clinical manifestation of visual attentional extinction.

Lingual and fusiform gyri in visual processing: a clinico-pathologic study of superior altitudinal hemianopia.

PubMed Central

Bogousslavsky, J; Miklossy, J; Deruaz, J P; Assal, G; Regli, F

1987-01-01

A macular-sparing superior altitudinal hemianopia with no visuo-psychic disturbance, except impaired visual learning, was associated with bilateral ischaemic necrosis of the lingual gyrus and only partial involvement of the fusiform gyrus on the left side. It is suggested that bilateral destruction of the lingual gyrus alone is not sufficient to affect complex visual processing. The fusiform gyrus probably has a critical role in colour integration, visuo-spatial processing, facial recognition and corresponding visual imagery. Involvement of the occipitotemporal projection system deep to the lingual gyri probably explained visual memory dysfunction, by a visuo-limbic disconnection. Impaired verbal memory may have been due to posterior involvement of the parahippocampal gyrus and underlying white matter, which may have disconnected the intact speech areas from the left medial temporal structures. Images PMID:3585386

Bilateral aniridia lenticular coloboma and snowflake retinal degeneration.

PubMed

Doganay, Selim; Emre, Sinan; Firat, Penpegül

2009-01-01

A 6-year-old boy presented with bilateral aniridia associated with lens coloboma and snowflake retinal degeneration. Ophthalmologic examination revealed bilateral corneal peripheral epithelial thickening and aniridia. Additionally, the patient had lenticular coloboma and snowflake retinal degeneration in both eyes. Intraocular pressure was 22 mm Hg bilaterally. The patient also had pendular nystagmus. Uncorrected visual acuity was counting fingers at 2 meters for both eyes, but improved to 0.2 and 0.05, respectively, with correction. Congenital aniridia has been reported with various ophthalmic pathologies, but this is the first case to display bilateral lenticular coloboma and snowflake retinal degeneration associated with aniridia.

Age-Specific Effects of Mirror-Muscle Activity on Cross-Limb Adaptations Under Mirror and Non-Mirror Visual Feedback Conditions.

PubMed

Reissig, Paola; Stöckel, Tino; Garry, Michael I; Summers, Jeffery J; Hinder, Mark R

2015-01-01

Cross-limb transfer (CLT) describes the observation of bilateral performance gains due to unilateral motor practice. Previous research has suggested that CLT may be reduced, or absent, in older adults, possibly due to age-related structural and functional brain changes. Based on research showing increases in CLT due to the provision of mirror visual feedback (MVF) during task execution in young adults, our study aimed to investigate whether MVF can facilitate CLT in older adults, who are known to be more reliant on visual feedback for accurate motor performance. Participants (N = 53) engaged in a short-term training regime (300 movements) involving a ballistic finger task using their dominant hand, while being provided with either visual feedback of their active limb, or a mirror reflection of their active limb (superimposed over the quiescent limb). Performance in both limbs was examined before, during and following the unilateral training. Furthermore, we measured corticospinal excitability (using TMS) at these time points, and assessed muscle activity bilaterally during the task via EMG; these parameters were used to investigate the mechanisms mediating and predicting CLT. Training resulted in significant bilateral performance gains that did not differ as a result of age or visual feedback (both p > 0.1). Training also elicited bilateral increases in corticospinal excitability (p < 0.05). For younger adults, CLT was significantly predicted by performance gains in the trained hand (β = 0.47), whereas for older adults it was significantly predicted by mirror activity in the untrained hand during training (β = 0.60). The present study suggests that older adults are capable of exhibiting CLT to a similar degree to younger adults. The prominent role of mirror activity in the untrained hand for CLT in older adults indicates that bilateral cortical activity during unilateral motor tasks is a compensatory mechanism. In this particular task, MVF did not facilitate the extent of CLT.

N of 1, two contemporary arm, randomised controlled clinical trial for bilateral epicondylitis: a new study design

PubMed Central

Fante, Claudia Del; Perotti, Cesare; Pavesi, Claudio Francesco; Coscia, Davide; Scotti, Valeria; Tinelli, Carmine

2011-01-01

Objective To investigate the use of a novel study design in analysis of bilateral elbow pain. Design N of 1, two contemporary arm, open label, randomised controlled clinical trial. Setting A clinical epidemiologist at a university hospital in Pavia, Italy. Participants Two elbows with epicondylitis. Interventions Autologous platelet lysate versus “wait and see” strategy. Main outcome measures Visual analogue scale for pain on elbow extension and resisted wrist extension. Results Over six months’ follow-up, the patient experienced bilateral improvement in pain, but higher in the treated arm, with a drop in visual analogue scale for pain from 28 to 4 for right (control) arm (drop of 24 points) and from 67 to 10.5 for left (treated) arm (drop of 56.5 points). Conclusions Platelet lysate might (or might not) work. Competing interests and lack of blinding might be relevant issues in the interpretation of trial results. However, the new study design can be applied to a number of conditions such as bilateral sport or trauma injuries, bilateral otitis, or any condition affecting chiral organs or limbs. PMID:22187187

Tagging cortical networks in emotion: a topographical analysis

PubMed Central

Keil, Andreas; Costa, Vincent; Smith, J. Carson; Sabatinelli, Dean; McGinnis, E. Menton; Bradley, Margaret M.; Lang, Peter J.

2013-01-01

Viewing emotional pictures is associated with heightened perception and attention, indexed by a relative increase in visual cortical activity. Visual cortical modulation by emotion is hypothesized to reflect re-entrant connectivity originating in higher-order cortical and/or limbic structures. The present study used dense-array electroencephalography and individual brain anatomy to investigate functional coupling between the visual cortex and other cortical areas during affective picture viewing. Participants viewed pleasant, neutral, and unpleasant pictures that flickered at a rate of 10 Hz to evoke steady-state visual evoked potentials (ssVEPs) in the EEG. The spectral power of ssVEPs was quantified using Fourier transform, and cortical sources were estimated using beamformer spatial filters based on individual structural magnetic resonance images. In addition to lower-tier visual cortex, a network of occipito-temporal and parietal (bilateral precuneus, inferior parietal lobules) structures showed enhanced ssVEP power when participants viewed emotional (either pleasant or unpleasant), compared to neutral pictures. Functional coupling during emotional processing was enhanced between the bilateral occipital poles and a network of temporal (left middle/inferior temporal gyrus), parietal (bilateral parietal lobules), and frontal (left middle/inferior frontal gyrus) structures. These results converge with findings from hemodynamic analyses of emotional picture viewing and suggest that viewing emotionally engaging stimuli is associated with the formation of functional links between visual cortex and the cortical regions underlying attention modulation and preparation for action. PMID:21954087

Are Covert Saccade Functionally Relevant in Vestibular Hypofunction?

PubMed

Hermann, R; Pelisson, D; Dumas, O; Urquizar, Ch; Truy, E; Tilikete, C

2018-06-01

The vestibulo-ocular reflex maintains gaze stabilization during angular or linear head accelerations, allowing adequate dynamic visual acuity. In case of bilateral vestibular hypofunction, patients use saccades to compensate for the reduced vestibulo-ocular reflex function, with covert saccades occurring even during the head displacement. In this study, we questioned whether covert saccades help maintain dynamic visual acuity, and evaluated which characteristic of these saccades are the most relevant to improve visual function. We prospectively included 18 patients with chronic bilateral vestibular hypofunction. Subjects underwent evaluation of dynamic visual acuity in the horizontal plane as well as video recording of their head and eye positions during horizontal head impulse tests in both directions (36 ears tested). Frequency, latency, consistency of covert saccade initiation, and gain of covert saccades as well as residual vestibulo-ocular reflex gain were calculated. We found no correlation between residual vestibulo-ocular reflex gain and dynamic visual acuity. Dynamic visual acuity performance was however positively correlated with the frequency and gain of covert saccades and negatively correlated with covert saccade latency. There was no correlation between consistency of covert saccade initiation and dynamic visual acuity. Even though gaze stabilization in space during covert saccades might be of very short duration, these refixation saccades seem to improve vision in patients with bilateral vestibular hypofunction during angular head impulses. These findings emphasize the need for specific rehabilitation technics that favor the triggering of covert saccades. The physiological origin of covert saccades is discussed.

Perda de massa em ventos empoeirados de estrelas supergigantes

NASA Astrophysics Data System (ADS)

Vidotto, A. A.; Jatenco-Pereira, V.

2003-08-01

Em praticamente todas as regiões do diagrama HR, as estrelas apresentam evidências observacionais de perda de massa. Na literatura, pode-se encontrar trabalhos que tratam tanto do diagnóstico da perda de massa como da construção de modelos que visam explicá-la. O amortecimento de ondas Alfvén tem sido utilizado como mecanismo de aceleração de ventos homogêneos. Entretanto, sabe-se que os envelopes de estrelas frias contêm grãos sólidos e moléculas. Com o intuito de estudar a interação entre as ondas Alfvén e a poeira e a sua conseqüência na aceleração do vento estelar, Falceta-Gonçalves & Jatenco-Pereira (2002) desenvolveram um modelo de perda de massa para estrelas supergigantes. Neste trabalho, apresentamos um estudo do modelo acima proposto para avaliar a dependência da taxa de perda de massa com alguns parâmetros iniciais como, por exemplo, a densidade r0, o campo magnético B0, o comprimento de amortecimento da onda L0, seu fluxo f0, entre outros. Sendo assim, aumentando f0 de 10% a partir de valores de referência, vimos que aumenta consideravelmente, enquanto que um aumento de mesmo valor em r0, B0 e L0 acarreta uma diminuição em .

Eye drops preservative as the cause of corneal band keratopathy in long-term pilocarpine hydrochloride treatment.

PubMed

Pavicić-Astalos, Jasna; Lacmanović-Loncar, Valentina; Petric-Vicković, Ivanka; Sarić, Dean; Mandić, Zdravko; Csik, Tigrena; Susić, Nikola

2012-03-01

The aim is to present a patient with severe bilateral corneal complications after long-term antiglaucoma treatment with 1% pilocarpine hydrochloride (Pilokarpin, Pliva, Zagreb, Croatia) and its management. A patient with narrow-angle glaucoma treated with 1% topical pilocarpine hydrochloride eye drops for the last twenty years complained of impaired vision, intermittent visual haloes and eye redness. Ophthalmologic examination showed bilateral band keratopathy, peripheral laser iridotomy, medicamentous myosis, brown nuclear cataract, and synchysis scintillans of his right eye. Band keratopathy was thought to have resulted from the presence of the preservative phenylmercuric nitrate in the pilocarpine hydrochloride eye drops. Treatment of the patient consisted of two separate procedures for both eyes, i.e. phaco trabeculectomy and six months later corneal procedure including abrasion of corneal epithelium followed by removal of the superficial stromal calcium deposits by means of a 3.75% ethylenediaminetetraacetic (EDTA) solution. After phaco trabeculectomy, visual acuity was 0.8 on both eyes. Bilateral visual improvement with visual acuity 1.0 was recorded after corneal treatment with EDTA. In conclusion, one must be aware of preservative complications in long-term topical use, such as band keratopathy that can be visually incapacitating. Surgical treatment using EDTA is safe and effective treatment for band keratopathy.

Visual agnosia and prosopagnosia secondary to melanoma metastases: case report

PubMed Central

Frota, Norberto Anízio Ferreira; Pinto, Lécio Figueira; Porto, Claudia Sellitto; de Aguia, Paulo Henrique Pires; Castro, Luiz Henrique Martins; Caramelli, Paulo

2007-01-01

The association of visual agnosia and prosopagnosia with cerebral metastasis is very rare. The presence of symmetric and bilateral cerebral metastases of melanoma is also uncommon.We report the case of a 34 year-old man who was admitted to hospital with seizures and a three-month history of headache, with blurred vision during the past month. A previous history of melanoma resection was obtained. CT of the skull showed bilateral heterogeneous hypodense lesions in the occipito-temporal regions, with a ring pattern of contrast enhancement. Surgical resection of both metastatic lesions was performed after which the patient developed visual agnosia and prosopagnosia. On follow-up, he showed partial recovery of visual agnosia, while prosopagnosia was still evident. The relevance of this case is the rare presentation of metastatic malignant melanoma affecting homologous occipito-temporal areas associated with prosopagnosia and associative visual agnosia. PMID:29213375

γ-oscillations modulated by picture naming and word reading: intracranial recording in epileptic patients.

PubMed

Wu, Helen C; Nagasawa, Tetsuro; Brown, Erik C; Juhasz, Csaba; Rothermel, Robert; Hoechstetter, Karsten; Shah, Aashit; Mittal, Sandeep; Fuerst, Darren; Sood, Sandeep; Asano, Eishi

2011-10-01

We measured cortical gamma-oscillations in response to visual-language tasks consisting of picture naming and word reading in an effort to better understand human visual-language pathways. We studied six patients with focal epilepsy who underwent extraoperative electrocorticography (ECoG) recording. Patients were asked to overtly name images presented sequentially in the picture naming task and to overtly read written words in the reading task. Both tasks commonly elicited gamma-augmentation (maximally at 80-100 Hz) on ECoG in the occipital, inferior-occipital-temporal and inferior-Rolandic areas, bilaterally. Picture naming, compared to reading task, elicited greater gamma-augmentation in portions of pre-motor areas as well as occipital and inferior-occipital-temporal areas, bilaterally. In contrast, word reading elicited greater gamma-augmentation in portions of bilateral occipital, left occipital-temporal and left superior-posterior-parietal areas. Gamma-attenuation was elicited by both tasks in portions of posterior cingulate and ventral premotor-prefrontal areas bilaterally. The number of letters in a presented word was positively correlated to the degree of gamma-augmentation in the medial occipital areas. Gamma-augmentation measured on ECoG identified cortical areas commonly and differentially involved in picture naming and reading tasks. Longer words may activate the primary visual cortex for the more peripheral field. The present study increases our understanding of the visual-language pathways. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Psychophysical and neuroimaging responses to moving stimuli in a patient with the Riddoch phenomenon due to bilateral visual cortex lesions.

PubMed

Arcaro, Michael J; Thaler, Lore; Quinlan, Derek J; Monaco, Simona; Khan, Sarah; Valyear, Kenneth F; Goebel, Rainer; Dutton, Gordon N; Goodale, Melvyn A; Kastner, Sabine; Culham, Jody C

2018-05-09

Patients with injury to early visual cortex or its inputs can display the Riddoch phenomenon: preserved awareness for moving but not stationary stimuli. We provide a detailed case report of a patient with the Riddoch phenomenon, MC. MC has extensive bilateral lesions to occipitotemporal cortex that include most early visual cortex and complete blindness in visual field perimetry testing with static targets. Nevertheless, she shows a remarkably robust preserved ability to perceive motion, enabling her to navigate through cluttered environments and perform actions like catching moving balls. Comparisons of MC's structural magnetic resonance imaging (MRI) data to a probabilistic atlas based on controls reveals that MC's lesions encompass the posterior, lateral, and ventral early visual cortex bilaterally (V1, V2, V3A/B, LO1/2, TO1/2, hV4 and VO1 in both hemispheres) as well as more extensive damage to right parietal (inferior parietal lobule) and left ventral occipitotemporal cortex (VO1, PHC1/2). She shows some sparing of anterior occipital cortex, which may account for her ability to see moving targets beyond ~15 degrees eccentricity during perimetry. Most strikingly, functional and structural MRI revealed robust and reliable spared functionality of the middle temporal motion complex (MT+) bilaterally. Moreover, consistent with her preserved ability to discriminate motion direction in psychophysical testing, MC also shows direction-selective adaptation in MT+. A variety of tests did not enable us to discern whether input to MT+ was driven by her spared anterior occipital cortex or subcortical inputs. Nevertheless, MC shows rich motion perception despite profoundly impaired static and form vision, combined with clear preservation of activation in MT+, thus supporting the role of MT+ in the Riddoch phenomenon. Copyright © 2018 Elsevier Ltd. All rights reserved.

Auditory biofeedback substitutes for loss of sensory information in maintaining stance.

PubMed

Dozza, Marco; Horak, Fay B; Chiari, Lorenzo

2007-03-01

The importance of sensory feedback for postural control in stance is evident from the balance improvements occurring when sensory information from the vestibular, somatosensory, and visual systems is available. However, the extent to which also audio-biofeedback (ABF) information can improve balance has not been determined. It is also unknown why additional artificial sensory feedback is more effective for some subjects than others and in some environmental contexts than others. The aim of this study was to determine the relative effectiveness of an ABF system to reduce postural sway in stance in healthy control subjects and in subjects with bilateral vestibular loss, under conditions of reduced vestibular, visual, and somatosensory inputs. This ABF system used a threshold region and non-linear scaling parameters customized for each individual, to provide subjects with pitch and volume coding of their body sway. ABF had the largest effect on reducing the body sway of the subjects with bilateral vestibular loss when the environment provided limited visual and somatosensory information; it had the smallest effect on reducing the sway of subjects with bilateral vestibular loss, when the environment provided full somatosensory information. The extent that all subjects substituted ABF information for their loss of sensory information was related to the extent that each subject was visually dependent or somatosensory-dependent for their postural control. Comparison of postural sway under a variety of sensory conditions suggests that patients with profound bilateral loss of vestibular function show larger than normal information redundancy among the remaining senses and ABF of trunk sway. The results support the hypothesis that the nervous system uses augmented sensory information differently depending both on the environment and on individual proclivities to rely on vestibular, somatosensory or visual information to control sway.

The compensatory dynamic of inter-hemispheric interactions in visuospatial attention revealed using rTMS and fMRI

PubMed Central

Plow, Ela B.; Cattaneo, Zaira; Carlson, Thomas A.; Alvarez, George A.; Pascual-Leone, Alvaro; Battelli, Lorella

2014-01-01

A balance of mutual tonic inhibition between bi-hemispheric posterior parietal cortices is believed to play an important role in bilateral visual attention. However, experimental support for this notion has been mainly drawn from clinical models of unilateral damage. We have previously shown that low-frequency repetitive TMS (rTMS) over the intraparietal sulcus (IPS) generates a contralateral attentional deficit in bilateral visual tracking. Here, we used functional magnetic resonance imaging (fMRI) to study whether rTMS temporarily disrupts the inter-hemispheric balance between bilateral IPS in visual attention. Following application of 1 Hz rTMS over the left IPS, subjects performed a bilateral visual tracking task while their brain activity was recorded using fMRI. Behaviorally, tracking accuracy was reduced immediately following rTMS. Areas ventro-lateral to left IPS, including inferior parietal lobule (IPL), lateral IPS (LIPS), and middle occipital gyrus (MoG), showed decreased activity following rTMS, while dorsomedial areas, such as Superior Parietal Lobule (SPL), Superior occipital gyrus (SoG), and lingual gyrus, as well as middle temporal areas (MT+), showed higher activity. The brain activity of the homologues of these regions in the un-stimulated, right hemisphere was reversed. Interestingly, the evolution of network-wide activation related to attentional behavior following rTMS showed that activation of most occipital synergists adaptively compensated for contralateral and ipsilateral decrement after rTMS, while activation of parietal synergists, and SoG remained competing. This pattern of ipsilateral and contralateral activations empirically supports the hypothesized loss of inter-hemispheric balance that underlies clinical manifestation of visual attentional extinction. PMID:24860462

Impact of vision loss among survivors of childhood central nervous system astroglial tumors.

PubMed

de Blank, Peter M K; Fisher, Michael J; Lu, Lu; Leisenring, Wendy M; Ness, Kirsten K; Sklar, Charles A; Stovall, Marilyn; Vukadinovich, Chris; Robison, Leslie L; Armstrong, Gregory T; Krull, Kevin R

2016-03-01

The impact of impaired vision on cognitive and psychosocial outcomes among long-term survivors of childhood low-grade gliomas has not been investigated previously but could inform therapeutic decision making. Data from the Childhood Cancer Survivor Study were used to investigate psychological outcomes (measures of cognitive/emotional function) and socioeconomic outcomes (education, income, employment, marital status, and independent living) among astroglial tumor survivors grouped by 1) vision without impairment, 2) vision with impairment (including unilateral blindness, visual field deficits, and amblyopia), or 3) bilateral blindness. The effect of vision status on outcomes was examined with multivariate logistic regression with adjustments for age, sex, cranial radiation therapy, and medical comorbidities. Among 1233 survivors of childhood astroglial tumors 5 or more years after their diagnosis, 277 (22.5%) had visual impairment. In a multivariate analysis, survivors with bilateral blindness were more likely to be unmarried (adjusted odds ratio (OR), 4.7; 95% confidence interval [CI], 1.5-15.0), live with a caregiver (adjusted OR, 3.1; 95% CI, 1.3-7.5), and be unemployed (adjusted OR, 2.2; 95% CI, 1.1-4.5) in comparison with those without visual impairment. Bilateral blindness had no measurable effect on cognitive or emotional outcomes, and vision with impairment was not significantly associated with any psychological or socioeconomic outcomes. Adult survivors of childhood astroglial tumors with bilateral blindness were more likely to live unmarried and dependently and to be unemployed. Survivors with visual impairment but some remaining vision did not differ significantly with respect to psychological function and socioeconomic status from those without visual impairment. Cancer 2016;122:730-739. © 2016 American Cancer Society. © 2016 American Cancer Society.

Bilateral Proliferative Retinopathy as the Initial Presentation of Chronic Myeloid Leukemia

PubMed Central

Macedo, Mafalda S. F.; Figueiredo, Ana R. M.; Ferreira, Natália N.; Barbosa, Irene M. A.; Furtado, Maria João F. B. S.; Correia, Nuno F. C. B. A.; Gomes, Miguel P.; Lume, Miguel R. B.; Menéres, Maria João S.; Santos, Marinho M. N.; Meireles S., M. Angelina C.

2013-01-01

The authors report a rare case of a 48-year-old male with chronic myeloid leukemia (CML) who initially presented with a bilateral proliferative retinopathy. The patient complained of recent visual loss and floaters in both eyes (BE). Ophthalmologic evaluation revealed a best corrected visual acuity (BCVA) of 20/50 in the right eye and 20/200 in the left eye (LE). Fundoscopy showed the presence of bilateral peripheral capillary dropout with multiple retinal sea fan neovascularisations, which were confirmed on fluorescein angiography. Full blood count revealed hyperleukocytosis, thrombocytosis, anemia, and hyperuricemia. Bone marrow aspiration and biopsy showed the reciprocal chromosomal translocation t (9;22), diagnostic of CML. The patient was started on hydroxyurea, allopurinol and imatinib mesylate. He received bilateral panretinal laser photocoagulation and a vitrectomy was performed in the LE. The patient has been in complete hematologic, cytogenetic, and major molecular remission while on imatinib and his BCVA is 20/25 in BE. PMID:24339689

Hummingbirds generate bilateral vortex loops during hovering: evidence from flow visualization

NASA Astrophysics Data System (ADS)

Pournazeri, Sam; Segre, Paolo S.; Princevac, Marko; Altshuler, Douglas L.

2012-12-01

Visualization of the vortex wake of a flying animal provides understanding of how wingbeat kinematics are translated into the aerodynamic forces for powering and controlling flight. Two general vortex flow patterns have been proposed for the wake of hovering hummingbirds: (1) The two wings form a single, merged vortex ring during each wing stroke; and (2) the two wings form bilateral vortex loops during each wing stroke. The second pattern was proposed after a study with particle image velocimetry that demonstrated bilateral source flows in a horizontal measurement plane underneath hovering Anna's hummingbirds ( Calypte anna). Proof of this hypothesis requires a clear perspective of bilateral pairs of vortices. Here, we used high-speed image sequences (500 frames per second) of C. anna hover feeding within a white plume to visualize the vortex wake from multiple perspectives. The films revealed two key structural features: (1) Two distinct jets of downwards airflow are present under each wing; and (2) vortex loops around each jet are shed during each upstroke and downstroke. To aid in the interpretation of the flow visualization data, we analyzed high-speed kinematic data (1,000 frames per second) of wing tips and wing roots as C. anna hovered in normal air. These data were used to refine several simplified models of vortex topology. The observed flow patterns can be explained by either a single loop model with an hourglass shape or a bilateral model, with the latter being more likely. When hovering in normal air, hummingbirds used an average stroke amplitude of 153.6° (range 148.9°-164.4°) and a wingbeat frequency of 38.5 Hz (range 38.1-39.1 Hz). When hovering in the white plume, hummingbirds used shallower stroke amplitudes ( bar{x} = 129.8°, range 116.3°-154.1°) and faster wingbeat frequencies ( bar{x} = 41.1 Hz, range 38.5-44.7 Hz), although the bilateral jets and associated vortices were observed across the full kinematic range. The plume did not significantly alter the air density or constrain the sustained muscle contractile frequency. Instead, higher wingbeat frequencies likely incurred a higher metabolic cost with the possible benefit of allowing the birds to more rapidly escape from the visually disruptive plume.

Hummingbirds generate bilateral vortex loops during hovering: evidence from flow visualization

NASA Astrophysics Data System (ADS)

Pournazeri, Sam; Segre, Paolo S.; Princevac, Marko; Altshuler, Douglas L.

2013-01-01

Visualization of the vortex wake of a flying animal provides understanding of how wingbeat kinematics are translated into the aerodynamic forces for powering and controlling flight. Two general vortex flow patterns have been proposed for the wake of hovering hummingbirds: (1) The two wings form a single, merged vortex ring during each wing stroke; and (2) the two wings form bilateral vortex loops during each wing stroke. The second pattern was proposed after a study with particle image velocimetry that demonstrated bilateral source flows in a horizontal measurement plane underneath hovering Anna's hummingbirds ( Calypte anna). Proof of this hypothesis requires a clear perspective of bilateral pairs of vortices. Here, we used high-speed image sequences (500 frames per second) of C. anna hover feeding within a white plume to visualize the vortex wake from multiple perspectives. The films revealed two key structural features: (1) Two distinct jets of downwards airflow are present under each wing; and (2) vortex loops around each jet are shed during each upstroke and downstroke. To aid in the interpretation of the flow visualization data, we analyzed high-speed kinematic data (1,000 frames per second) of wing tips and wing roots as C. anna hovered in normal air. These data were used to refine several simplified models of vortex topology. The observed flow patterns can be explained by either a single loop model with an hourglass shape or a bilateral model, with the latter being more likely. When hovering in normal air, hummingbirds used an average stroke amplitude of 153.6° (range 148.9°-164.4°) and a wingbeat frequency of 38.5 Hz (range 38.1-39.1 Hz). When hovering in the white plume, hummingbirds used shallower stroke amplitudes ( bar{x} = 129.8°, range 116.3°-154.1°) and faster wingbeat frequencies ( bar{x} = 41.1 Hz, range 38.5-44.7 Hz), although the bilateral jets and associated vortices were observed across the full kinematic range. The plume did not significantly alter the air density or constrain the sustained muscle contractile frequency. Instead, higher wingbeat frequencies likely incurred a higher metabolic cost with the possible benefit of allowing the birds to more rapidly escape from the visually disruptive plume.

[Case of pediatric chronic myeloid leukemia with bilateral visual loss onset].

PubMed

Hara, Yusuke; Kamura, Yumi; Oikawa, Aki; Shichino, Hiroyuki; Mugishima, Hideo; Goto, Hiroshi

2010-05-01

Chronic myeloid leukemia (CML) during childhood is rare, and only been a few cases showed visual disturbances as an initial symptom. We report a pediatric CML case diagnosed by bilateral visual loss. An 11-year-old boy complained of visual loss in both eyes. His best corrected visual acuity was 0.5 in the right eye and 0.2 in the left. Fundus examination showed disc swelling, dilated and tortuous retinal veins and multiple elevated retinal lesions with hemorrhages of various size from one-forth to four disc diameters in both eyes. He was diagnosed as having CML by leucocytosis and systematic work-up including Philadelphia chromosome-positive, BCR-ABL kinase domain in peripheral blood and bone marrow. The ocular findings improved after treatment with hydroxyurea, leukocytaphresis and imatinib. His best corrected visual acuity improved to 0.7 in both eyes. Recent leukemia therapy including imatinib is effective not only for ocular lesions but also to induce hematological remission in childhood CML.

Return of visual function after bilateral visual loss following flow diversion embolization of a giant ophthalmic aneurysm due to both reduction in mass effect and reduction in aneurysm pulsation.

PubMed

Patel, Saharsh; Fargen, Kyle M; Peters, Keith; Krall, Peter; Samy, Hazem; Hoh, Brian L

2014-01-10

Large and giant paraclinoid aneurysms are challenging to treat by either surgical or endovascular means. Visual dysfunction secondary to optic nerve compression and its relationship with aneurysm size, pulsation and thrombosis is poorly understood. We present a patient with a giant paraclinoid aneurysm resulting in bilateral visual loss that worsened following placement of a Pipeline Embolization Device and adjunctive coiling. Visual worsening occurred in conjunction with aneurysm thrombosis, increase in maximal aneurysm diameter and new adjacent edema. Her visual function spontaneously improved in a delayed fashion to better than pre-procedure, in conjunction with reduced aneurysmal mass effect, size and pulsation artifact on MRI. This report documents detailed ophthalmologic and MRI evidence for the role of thrombosis, aneurysm mass effect and aneurysm pulsation as causative etiologies for both cranial nerve dysfunction and delayed resolution following flow diversion treatment of large cerebral aneurysms.

Association between visual impairment and patient-reported visual disability at different stages of cataract surgery.

PubMed

Acosta-Rojas, E Ruthy; Comas, Mercè; Sala, Maria; Castells, Xavier

2006-10-01

To evaluate the association between visual impairment (visual acuity, contrast sensitivity, stereopsis) and patient-reported visual disability at different stages of cataract surgery. A cohort of 104 patients aged 60 years and over with bilateral cataract was assessed preoperatively, after first-eye surgery (monocular pseudophakia) and after second-eye surgery (binocular pseudophakia). Partial correlation coefficients (PCC) and linear regression models were calculated. In patients with bilateral cataracts, visual disability was associated with visual acuity (PCC = -0.30) and, to a lesser extent, with contrast sensitivity (PCC = 0.16) and stereopsis (PCC = -0.09). In monocular and binocular pseudophakia, visual disability was more strongly associated with stereopsis (PCC = -0.26 monocular and -0.51 binocular) and contrast sensitivity (PCC = 0.18 monocular and 0.34 binocular) than with visual acuity (PCC = -0.18 monocular and -0.18 binocular). Visual acuity, contrast sensitivity and stereopsis accounted for between 17% and 42% of variance in visual disability. The association of visual impairment with patient-reported visual disability differed at each stage of cataract surgery. Measuring other forms of visual impairment independently from visual acuity, such as contrast sensitivity or stereopsis, could be important in evaluating both needs and outcomes in cataract surgery. More comprehensive assessment of the impact of cataract on patients should include measurement of both visual impairment and visual disability.

Early vitrectomy effective for bilateral combined anterior and posterior persistent fetal vasculature syndrome.

PubMed

Walsh, Mark K; Drenser, Kimberly A; Capone, Antonio; Trese, Michael T

2010-04-01

The purpose of this study was to review our surgical experience with patients with bilateral combined anterior and posterior persistent fetal vasculature syndrome (PFVS). We retrospectively reviewed the charts of all patients seen in our tertiary care pediatric retinal practice from 1988 to 2008 with a potential diagnosis of bilateral PFVS with posterior involvement. Clinical diagnosis required the presence of either bilateral persistent hyaloidal stalk tissue with retinal involvement or bilateral dense retrolental fibrovascular plaques (usually with no posterior view preoperatively) without a family history or genetic testing consistent with Norrie disease or familial exudative vitreoretinopathy. Chart review showed 22 vitrectomized patients with clinical findings consistent with bilateral PFVS with posterior involvement who did not have a family history or genetic testing consistent with Norrie disease or familial exudative vitreoretinopathy. All 22 of these patients with posterior retinal involvement also had anterior findings and thus can be classified as combined anterior and posterior PFVS. Of the 13 patients with visual acuity follow-up data, 9 patients (69%) maintained at least light perception vision in at least 1 eye at last follow-up. Of the 28 operated eyes in 16 patients with follow-up data, 3 eyes (11%) were phthisical at last follow-up. Children with bilateral PFVS with posterior retinal involvement have a dismal visual prognosis if left unoperated. In this relatively large series of a rare condition, we find that vitrectomy with or without lensectomy is beneficial in bilateral combined anterior and posterior PFVS in two regards: maintenance or restoration of vision and avoidance of phthisis bulbi.

ERP effects of spatial attention and display search with unilateral and bilateral stimulus displays.

PubMed

Lange, J J; Wijers, A A; Mulder, L J; Mulder, G

1999-07-01

Two experiments were performed in which the effects of selective spatial attention on the ERPs elicited by unilateral and bilateral stimulus arrays were compared. In Experiment 1, subjects received a series of grating patterns. In the unilateral condition these gratings were presented one at a time, randomly to the right or left of fixation. In the bilateral condition, gratings were presented in pairs, one to each side of fixation. In the unilateral condition standard ERP effects of visual spatial attention were observed. However, in the bilateral condition we failed to observe an attention related posterior contralateral positivity (overlapping the P1 and N1 components, latency interval about 100-250 ms), as reported in several previous studies. In Experiment 2, we investigated whether attention related ERP lateralizations are affected by the task requirement to search among multiple objects in the visual field. We employed a task paradigm identical to that used by Luck et al. (Luck, S.J., Heinze, H.J., Mangun, G.R., Hillyard, S.A., 1990. Visual event-related potentials index focused attention within bilateral stimulus arrays. II. Functional dissociation of P1 and N1 components. Electroencephalogr. Clin. Neurophysiol. 75, 528-542). Four letters were presented to a visual hemifield, simultaneously to both the attended and unattended hemifields in the bilateral conditions, and to one hemifield only in the unilateral conditions. In a focused attention condition, subjects searched for a target letter at a fixed position, whereas they searched for the target letter among all four letters in the divided attention condition (as in the experiment of Luck et al., 1990). In the bilateral focused attention condition, only the contralateral P1 was enhanced. In the bilateral divided attention condition a prolonged posterior positivity was observed over the hemisphere contralateral to the attended hemifield, comparable to the results of Luck et al. (1990). A comparison of the ERPs elicited in the focused and divided attention conditions revealed a prolonged 'search related negativity'. We discuss possible interactions between this negativity and attention related lateralizations. The display search negativity consisted of two phases, one phase comprised a midline occipital negativity, developing first over the ipsilateral scalp, while the second phase involved two symmetrical occipitotemporal negativities, strongly resembling the N1 in their topography. The display search effect could be modelled with a dipole in a medial occipital (possibly striate) region and two symmetrical dipoles in occipitotemporal brain areas. We hypothesize that this effect reflects a process of rechecking the decaying information of iconic memory in the occipitotemporal object recognition pathway.

Blindness and visual impairment in Remo, Ogun State, Nigeria: a hospital-based study.

PubMed

Otulana, T O

2012-09-01

This study was conducted to determine the magnitude and causes of blindness and visual impairment in Remo, Ogun State, Nigeria. A retrospective clinic based study to analyse the cases of patients with blindness in general hospitals of Iperu and Isara areas of Ogun state between May 2005 and December 2005. The data of demographic characteristics and diagnosis were retrieved from the outpatient cards. Three hundred and sixty-nine cases registered in the eye clinic during the period of the study and were examined. 177 were males and 190 were females. The age range of patients seen was between 17 days and 89years with a mean age of 43.3 years, ± 23.62(SD). 116 patients were aged 70years and above while 13 patients were less than 10years. 29.5% of the clinic attendance were uniocularly blind, 21.1% were bilaterally blind while 25 2% were visually impaired. 55.1% of the bilateral blindness was in males. 30.8% cases of the bilaterally blind were from age related cataract, 23.1% from glaucoma, 6 cases were due to Retinitis Pigmentosa and 3 from pterygium, Cataract followed by glaucoma was the leading cause of uniocular blindness. Cataract was responsible for 66.7% of visually impairment. Blindness and visual impairment is a public health problem in Remo Ogun State, Nigeria; cataract, glaucoma and pterygium were the important causes of blindness and visual impairment. The major causes of blindness in this part of Ogun state are preventable.

Sparing of Sensitivity to Biological Motion but Not of Global Motion after Early Visual Deprivation

ERIC Educational Resources Information Center

Hadad, Bat-Sheva; Maurer, Daphne; Lewis, Terri L.

2012-01-01

Patients deprived of visual experience during infancy by dense bilateral congenital cataracts later show marked deficits in the perception of global motion (dorsal visual stream) and global form (ventral visual stream). We expected that they would also show marked deficits in sensitivity to biological motion, which is normally processed in the…

Visual outcomes after spectacles treatment in children with bilateral high refractive amblyopia.

PubMed

Lin, Pei-Wen; Chang, Hsueh-Wen; Lai, Ing-Chou; Teng, Mei-Ching

2016-11-01

The aim was to investigate the visual outcomes of treatment with spectacles for bilateral high refractive amblyopia in children three to eight years of age. Children with previously untreated bilateral refractive amblyopia were enrolled. Bilateral high refractive amblyopia was defined as visual acuity (VA) being worse than 6/9 in both eyes in the presence of 5.00 D or more of hyperopia, 5.00 D or more of myopia and 2.00 D or more of astigmatism. Full myopic and astigmatic refractive errors were corrected, and the hyperopic refractive errors were corrected within 1.00 D of the full correction. All children received visual assessments at four-weekly intervals. VA, Worth four-dot test and Randot preschool stereotest were assessed at baseline and every four weeks for two years. Twenty-eight children with previously untreated bilateral high refractive amblyopia were enrolled. The mean VA at baseline was 0.39 ± 0.24 logMAR and it significantly improved to 0.21, 0.14, 0.11, 0.05 and 0.0 logMAR at four, eight, 12, 24 weeks and 18 months, respectively (all p = 0.001). The mean stereoacuity (SA) was 1,143 ± 617 arcsec at baseline and it significantly improved to 701, 532, 429, 211 and 98 arcsec at four, eight, 12, 24 weeks and 18 months, respectively (all p = 0.001). The time interval for VA achieving 6/6 was significantly shorter in the eyes of low spherical equivalent (SE) (-2.00 D < SE < +2.00 D) than in those of high SE (SE > +2.00 D) (3.33 ± 2.75 months versus 8.11 ± 4.56 months, p = 0.0005). All subjects had normal fusion on Worth four-dot test at baseline and all follow-up visits. Refractive correction with good spectacles compliance improves VA and SA in young children with bilateral high refractive amblyopia. Patients with greater amounts of refractive error will achieve resolution of amblyopia with a longer time. © 2016 Optometry Australia.

A population-based study of visual impairment among pre-school children in Beijing: the Beijing study of visual impairment in children.

PubMed

Lu, Qing; Zheng, Yuanyuan; Sun, Baochen; Cui, Tongtong; Congdon, Nathan; Hu, Ailian; Chen, Jianhua; Shi, Jiliang

2009-06-01

To evaluate the prevalence and causes of visual impairment among Chinese children aged 3 to 6 years in Beijing. Population-based prevalence survey. Presenting and pinhole visual acuity were tested using picture optotypes or, in children with pinhole vision < 6/18, a Snellen tumbling E chart. Comprehensive eye examinations and cycloplegic refraction were carried out for children with pinhole vision < 6/18 in the better-seeing eye. All examinations were completed on 17,699 children aged 3 to 6 years (95.3% of sample). Subjects with bilateral correctable low vision (presenting vision < 6/18 correctable to >or= 6/18) numbered 57 (0.322%; 95% confidence interval [CI], 0.237% to 0.403%), while 14 (0.079%; 95% CI, 0.038% to 0.120%) had bilateral uncorrectable low vision (best-corrected vision of < 6/18 and >or= 3/60), and 5 subjects (0.028%; 95% CI, 0.004% to 0.054%) were bilaterally blind (best-corrected acuity < 3/60). The etiology of 76 cases of visual impairment included: refractive error in 57 children (75%), hereditary factors (microphthalmos, congenital cataract, congenital motor nystagmus, albinism, and optic nerve disease) in 13 children (17.1 %), amblyopia in 3 children (3.95%), and cortical blindness in 1 child (1.3%). The cause of visual impairment could not be established in 2 (2.63%) children. The prevalence of visual impairment did not differ by gender, but correctable low vision was significantly (P < .0001) more common among urban as compared with rural children. The leading causes of visual impairment among Chinese preschool-aged children are refractive error and hereditary eye diseases. A higher prevalence of refractive error is already present among urban as compared with rural children in this preschool population.

[Symptoms and lesion localization in visual agnosia].

PubMed

Suzuki, Kyoko

2004-11-01

There are two cortical visual processing streams, the ventral and dorsal stream. The ventral visual stream plays the major role in constructing our perceptual representation of the visual world and the objects within it. Disturbance of visual processing at any stage of the ventral stream could result in impairment of visual recognition. Thus we need systematic investigations to diagnose visual agnosia and its type. Two types of category-selective visual agnosia, prosopagnosia and landmark agnosia, are different from others in that patients could recognize a face as a face and buildings as buildings, but could not identify an individual person or building. Neuronal bases of prosopagnosia and landmark agnosia are distinct. Importance of the right fusiform gyrus for face recognition was confirmed by both clinical and neuroimaging studies. Landmark agnosia is related to lesions in the right parahippocampal gyrus. Enlarged lesions including both the right fusiform and parahippocampal gyri can result in prosopagnosia and landmark agnosia at the same time. Category non-selective visual agnosia is related to bilateral occipito-temporal lesions, which is in agreement with the results of neuroimaging studies that revealed activation of the bilateral occipito-temporal during object recognition tasks.

Right away: A late, right-lateralized category effect complements an early, left-lateralized category effect in visual search.

PubMed

Constable, Merryn D; Becker, Stefanie I

2017-10-01

According to the Sapir-Whorf hypothesis, learned semantic categories can influence early perceptual processes. A central finding in support of this view is the lateralized category effect-namely, the finding that categorically different colors (e.g., blue and green hues) can be discriminated faster than colors within the same color category (e.g., different hues of green), especially when they are presented in the right visual field. Because the right visual field projects to the left hemisphere, this finding has been popularly couched in terms of the left-lateralization of language. However, other studies have reported bilateral category effects, which has led some researchers to question the linguistic origins of the effect. Here we examined the time course of lateralized and bilateral category effects in the classical visual search paradigm by means of eyetracking and RT distribution analyses. Our results show a bilateral category effect in the manual responses, which is combined of an early, left-lateralized category effect and a later, right-lateralized category effect. The newly discovered late, right-lateralized category effect occurred only when observers had difficulty locating the target, indicating a specialization of the right hemisphere to find categorically different targets after an initial error. The finding that early and late stages of visual search show different lateralized category effects can explain a wide range of previously discrepant findings.

Pros and cons of immediately sequential bilateral cataract surgery (ISBCS).

PubMed

Grzybowski, Andrzej; Wasinska-Borowiec, Weronika; Claoué, Charles

2016-01-01

Immediately sequential bilateral cataract surgery (ISBCS) is currently a "hot topic" in ophthalmology. There are well-documented advantages in terms of quicker visual rehabilitation and reduced costs. The risk of bilateral simultaneous endophthalmitis and bilateral blindness is now recognized to be minuscule with the advent of intracameral antibiotics and modern management of endophthalmitis. Refractive surprises are rare for normal eyes and with the use of optical biometry. Where a general anesthetic is indicated for cataract surgery, the risk of death from a second anesthetic is much higher than the risk of blindness. A widely recognized protocol from the International Society of Bilateral Cataract Surgeons needs to be adhered to if surgeons wish to start practicing ISBCS.

Combined etiology for bilateral and simultaneous optic neuropathy in a patient with ciancobalamin deficit and hepatitis C treated with peg-interferon and ribavirin.

PubMed

Pantalon, Anca Delia; Danielescu, Ciprian; Chiseliță, Dorin

2016-01-01

We report the case of a 53-year-old female patient who developed bilateral sudden visual acuity loss after 15 weeks from the initiation of Peg-Interferon and Ribavirin treatment for hepatitis C. Debut was simultaneous and asymmetric, reported in the morning, at awakening. No pain or other symptom was reported by the patient. Results. At presentation, visual acuity was 0.2 in RE and 3/ 50 in LE. Pupillary reflexes were sluggish and severe dyschromatopsia was documented in both eyes (Ishihara plates). Fundus examination revealed bilateral pale optic disc edema, more prominent in LE, with splinter hemorrhages in the RNFL around the optic disk. Visual field exam demonstrated severe defects in 3 quadrants of the RE, whereas in the LE, it was impossible to perform the investigation due to VA<0.1. Neurologic evaluation was normal; other possible causes of systemic vasculitis were excluded by negative lab tests. Acute inflammatory markers (fibrinogen and ESR) and mild pancytopenia were the only documented laboratory changes in this patient. Anamnesis cleared the traditional risk factors for conventional AION (hypertension, diabetes, ischemic heart disease, and hypercholesterolemia). Cranial and orbital CT scan and MRI findings were normal. Patient was withdrawn from the Interferon and Ribavirin treatment and was administered methyl prednisolone pulse therapy (1g/ day) for 3 days, continued with oral Prednisone (60 mg/ day) tapered slowly for over 12 weeks. VA increased to 0.8 during treatment in the RE, but visual recovery in the LE was not as spectacular (0.16) as in the fellow eye. Modified latencies and amplitudes in evoked visual potentials examination during 4 months time emphasized bilateral optic atrophy. Optic nerve sufferance was amplified by a low level of vitamin B12, detected by chance at the last eye visit. Due to the general condition, dietary supplementation was not possible. Conclusion. A case of a patient with bilateral and simultaneous NAION caused by IFN and Ribavirin treatment for hepatitis C, who was also vitamin B12 deficient, was analyzed. Therefore, a combined etiology for optic atrophy was explained.

A bilateral advantage for maintaining objects in visual short term memory.

PubMed

Holt, Jessica L; Delvenne, Jean-François

2015-01-01

Research has shown that attentional pre-cues can subsequently influence the transfer of information into visual short term memory (VSTM) (Schmidt, B., Vogel, E., Woodman, G., & Luck, S. (2002). Voluntary and automatic attentional control of visual working memory. Perception & Psychophysics, 64(5), 754-763). However, studies also suggest that those effects are constrained by the hemifield alignment of the pre-cues (Holt, J. L., & Delvenne, J.-F. (2014). A bilateral advantage in controlling access to visual short-term memory. Experimental Psychology, 61(2), 127-133), revealing better recall when distributed across hemifields relative to within a single hemifield (otherwise known as a bilateral field advantage). By manipulating the duration of the retention interval in a colour change detection task (1s, 3s), we investigated whether selective pre-cues can also influence how information is later maintained in VSTM. The results revealed that the pre-cues influenced the maintenance of the colours in VSTM, promoting consistent performance across retention intervals (Experiments 1 & 4). However, those effects were only shown when the pre-cues were directed to stimuli displayed across hemifields relative to stimuli within a single hemifield. Importantly, the results were not replicated when participants were required to memorise colours (Experiment 2) or locations (Experiment 3) in the absence of spatial pre-cues. Those findings strongly suggest that attentional pre-cues have a strong influence on both the transfer of information in VSTM and its subsequent maintenance, allowing bilateral items to better survive decay. Copyright © 2014 Elsevier B.V. All rights reserved.

Two cases of bilateral amiodarone-associated optic neuropathy.

PubMed

Chassang, B; Bonnin, N; Moisset, X; Citron, B; Clavelou, P; Chiambaretta, F

2014-03-01

The widespread use of amiodarone is limited by its toxicity, notably to the optic nerve. We report two cases of bilateral optic nerve neuropathy due to amiodarone, and provide a detailed description of the disease. The first case was a 59-year-old man complaining from insidious monocular loss of vision within ten months of initiating amiodarone. Funduscopy and optical coherence tomography showed bilateral optic disc edema. The second case was a 72-year-old man presenting with a decrease in visual acuity in his left eye for a month. Funduscopy showed a left optic nerve edema, and fluorescein angiography showed bilateral papillitis. In both cases, the clinical presentation was not suggestive of ischemic neuropathy, because of the preservation of visual acuity and the insidious onset. In addition, both cardiovascular and inflammatory work-up were normal. An amiodarone-associated neuropathy was suspected, and amiodarone was discontinued with the approval of the cardiologist, with complete regression of the papilledema and a stabilization of visual symptoms. Differentiating between amiodarone-associated optic neuropathy and anterior ischemic optic neuropathy may be complicated by the cardiovascular background of such patients. The major criterion is the absence of a severe decrease in visual acuity; other criteria are the normality of cardiovascular and inflammatory work-up, and the improvement or the absence of worsening of symptoms after discontinuation of amiodarone. Amiodarone-associated neuropathy remains a diagnosis of exclusion, and requires amiodarone discontinuation, which can only be done with the approval of a cardiologist, and sometimes requires replacement therapy. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Visual outcomes of patients bilaterally implanted with the extended range of vision intraocular lens: A prospective study

PubMed Central

Sachdev, Gitansha Shreyas; Ramamurthy, Shreyas; Sharma, Umesh; Dandapani, Ramamurthy

2018-01-01

Purpose: The aim of this study was to analyze the objective and subjective visual outcomes of patients bilaterally implanted with the extended range of vision intraocular lens (EROV IOL), the Tecnis Symfony. Methods: This was a prospective interventional case series conducted at a tertiary eye care hospital in South India. The study included patients with bilateral implantation of EROV IOLs. The uncorrected and corrected visual acuity for distance, intermediate, and near vision was recorded at 6 weeks and 6 months’ postoperative visit. A subjective questionnaire was administered to assess spectacle independence, photic phenomenon, and overall satisfaction. All data were recorded using Microsoft Excel worksheet. The analyses were performed using SPSS for windows software. Results: Our study included fifty patients with bilateral implantation of EROV IOLs. The mean age was 59.84 ± 11.68 years. The mean uncorrected binocular distance, intermediate, and near visual acuity (in standard decimal equivalent) was 0.89,0.99 and 0.99 respectively, at 6 months’ postoperative visit. Ninety-six percent of the patients did not require spectacles for distance and 98% of the patients were free from spectacles for intermediate and near vision. 94% of our patients perceived no or minimal photic phenomena such as glare and halos. The mean subjective patient satisfaction score (out of 10) for distance, intermediate, and near was 9, 10, and 9, respectively. Conclusion: The EROV IOLs demonstrated high levels of spectacle independence for distance, intermediate, and near vision. The incidence of photic phenomena observed was minimal with a high level of patient satisfaction. PMID:29480252

Impact of Juvenile Idiopathic Arthritis Associated Uveitis in Early Adulthood

PubMed Central

Vernie, Lenneke A.; Rothova, Aniki; v. d. Doe, Patricia; Los, Leonoor I.; Schalij-Delfos, Nicoline E.; de Boer, Joke H.

2016-01-01

Background Typically juvenile idiopathic arthritis (JIA)-associated uveitis (further referred as ‘JIA-uveitis’) has its onset in childhood, but some patients suffer its, sometimes visual threatening, complications or ongoing disease activity in adulthood. The objective of this study was to analyze uveitis activity, complications and visual prognosis in adulthood. Methods In this multicenter study, 67 adult patients (129 affected eyes) with JIA-uveitis were retrospectively studied for best corrected visual acuity, visual fields, uveitis activity, topical/systemic treatments, ocular complications, and ocular surgeries during their 18th, 22nd and 30th year of life. Because treatment strategies changed after the year 1990, outcomes were stratified for onset of uveitis before and after 1990. Results Sixty-two of all 67 included patients (93%) had bilateral uveitis. During their 18th life year, 4/52 patients (8%) had complete remission, 28/52 (54%) had uveitis activity and 37/51 patients (73%) were on systemic immunomodulatory treatment. Bilateral visual impairment or legal blindness occurred in 2/51 patients (4%); unilateral visual impairment or legal blindness occurred in 17/51 patients (33%) aged 18 years. The visual prognosis appeared to be slightly better for patients with uveitis onset after the year 1990 (for uveitis onset before 1990 (n = 7) four patients (58%) and for uveitis onset after 1990 (n = 44) 13 patients (30%) were either visual impaired or blind). At least one ocular surgery was performed in 10/24 patients (42%) between their 18th and 22nd year of life. Conclusions Bilateral visual outcome in early adulthood in patients with JIA-uveitis appears to be fairly good, although one third of the patients developed one visually impaired or blind eye. However, a fair amount of the patients suffered from ongoing uveitis activity and needed ongoing treatment as well as surgical interventions. Awareness of these findings is important for ophthalmologists and rheumatologists treating patients with JIA-uveitis, as well as for the patients themselves. PMID:27723840

Bilateral rhegmatogenous retinal detachment due to unusual retinal degeneration in Down syndrome: A case report.

PubMed

Yonemoto, Yumiko; Morishita, Seita; Fukumoto, Masanori; Mimura, Masashi; Sato, Takaki; Kida, Teruyo; Kojima, Shota; Oku, Hidehiro; Sugasawa, Jun; Ikeda, Tsunehiko

2018-06-01

The aim of this study was to report a case of Down syndrome (DS) complicated with bilateral retinal detachment (RD) due to unusual retinal degeneration. A 9-year-old girl complained of bilateral visual disturbance during a follow-up examination for myopia and strabismus. Slit-lamp examination revealed moderate posterior subcapsular cataract in both eyes. B-mode echography showed bilateral bullous RD; however, it was difficult to detect the causal retinal breaks due to poor mydriasis. For treatment, the patient underwent bilateral lensectomy, vitrectomy, and silicone oil tamponade. Intraoperative findings revealed symmetrical retinal breaks and unusual caterpillar-like retinal degeneration on the upper temporal side of both eyes. Three months later, the patient underwent bilateral silicone oil removal and intraocular lens implantation. In this case, the retinal degeneration was morphologically different from retinal lattice degeneration, thus suggesting that it might be involved in the onset of DS-related bilateral RD.

[A case of carbon monoxide poisoning by explosion of coal mine presenting as visual agnosia: re-evaluation after 40 years].

PubMed

Takaiwa, Akiko; Yamashita, Kenichiro; Nomura, Takuo; Shida, Kenshiro; Taniwaki, Takayuki

2005-11-01

We re-evaluated a case of carbon monoxide poisoning presenting as visual agnosia who had been injured by explosion of Miike-Mikawa coal mine 40 years ago. In an early stage, his main neuropsychological symptoms were visual agnosia, severe anterograde amnesia, alexia, agraphia, constructional apraxia, left hemispatial neglect and psychic paralysis of gaze, in addition to pyramidal and extra pyramidal signs. At the time of re-evaluation after 40 years, he still showed visual agnosia associated with agraphia and constructional apraxia. Concerning visual agnosia, recognition of the real object was preserved, while recognition of object photographs and picture was impaired. Thus, this case was considered to have picture agnosia as he could not recognize the object by pictorial cues on the second dimensional space. MRI examination revealed low signal intensity lesions and cortical atrophy in the bilateral parieto-occipital lobes on T1-weighted images. Therefore, the bilateral parieto-occipital lesions are likely to be responsible for his picture agnosia.

Bilateral Glaucomatous Optic Neuropathy Caused by Eye Rubbing.

PubMed

Savastano, Alfonso; Savastano, Maria Cristina; Carlomusto, Laura; Savastano, Silvio

2015-01-01

In this report, we describe a particular condition of a 52-year-old man who showed advanced bilateral glaucomatous-like optic disc damage, even though the intraocular pressure resulted normal during all examinations performed. Visual field test, steady-state pattern electroretinogram, retinal nerve fiber layer and retinal tomographic evaluations were performed to evaluate the optic disc damage. Over a 4-year observational period, his visual acuity decreased to 12/20 in the right eye and counting fingers in the left eye. Visual fields were severely compromised, and intraocular pressure values were not superior to 14 mm Hg during routine examinations. An accurate anamnesis and the suspicion of this disease represent a crucial aspect to establish the correct diagnosis. In fact, our patient strongly rubbed his eyes for more than 10 h per day. Recurrent and continuous eye rubbing can induce progressive optic neuropathy, causing severe visual field damage similar to the pathology of advanced glaucoma.

Can foam sclerotherapy be used to safely treat bilateral varicose veins?

PubMed

Bhogal, R H; Moffat, C E; Coney, P; Nyamekye, I K

2012-02-01

We assessed the use of ultrasound guided foam sclerotherapy (UGFS) to treat bilateral varicose veins either as synchronous or interval procedures. We specifically assessed total foam volume usage and its influence on early outcome and complications. We reviewed our prospectively compiled computerised database of patients with bilateral varicose veins who have undergone UGFS. Duplex findings, foam volumes used and clinical outcome were assessed. One hundred and twelve patients had undergone UGFS for bilateral varicose veins. Sixty-one had bilateral UGFS (122 legs) and 51 had interval UGFS (102 legs). Seventy-eight percent bilateral and 60% interval procedures were for single trunk disease. Median foam volumes per treatment episode were: 17.5 mls bilateral, and 10 mls interval FS. At two weeks 81% of legs had complete occlusion after bilateral UGFS compared to 70% after interval UGFS. One patient in the bilateral UGFS developed transient visual disturbance. There was no systemic complications in the interval UGFS. Bilateral foam sclerotherapy treatment did not adversly affect vein occlusion rates and there was no significant difference in complication rates between the two groups. Bilateral UGFS can be safely performed in selected patient presenting with bilateral varicose veins.

Altered Brain Network in Amyotrophic Lateral Sclerosis: A Resting Graph Theory-Based Network Study at Voxel-Wise Level.

PubMed

Zhou, Chaoyang; Hu, Xiaofei; Hu, Jun; Liang, Minglong; Yin, Xuntao; Chen, Lin; Zhang, Jiuquan; Wang, Jian

2016-01-01

Amyotrophic lateral sclerosis (ALS) is a rare degenerative disorder characterized by loss of upper and lower motor neurons. Neuroimaging has provided noticeable evidence that ALS is a complex disease, and shown that anatomical and functional lesions extend beyond precentral cortices and corticospinal tracts, to include the corpus callosum; frontal, sensory, and premotor cortices; thalamus; and midbrain. The aim of this study is to investigate graph theory-based functional network abnormalities at voxel-wise level in ALS patients on a whole brain scale. Forty-three ALS patients and 44 age- and sex-matched healthy volunteers were enrolled. The voxel-wise network degree centrality (DC), a commonly employed graph-based measure of network organization, was used to characterize the alteration of whole brain functional network. Compared with the controls, the ALS patients showed significant increase of DC in the left cerebellum posterior lobes, bilateral cerebellum crus, bilateral occipital poles, right orbital frontal lobe, and bilateral prefrontal lobes; significant decrease of DC in the bilateral primary motor cortex, bilateral sensory motor region, right prefrontal lobe, left bilateral precuneus, bilateral lateral temporal lobes, left cingulate cortex, and bilateral visual processing cortex. The DC's z-scores of right inferior occipital gyrus were significant negative correlated with the ALSFRS-r scores. Our findings confirm that the regions with abnormal network DC in ALS patients were located in multiple brain regions including primary motor, somatosensory and extra-motor areas, supporting the concept that ALS is a multisystem disorder. Specifically, our study found that DC in the visual areas was altered and ALS patients with higher DC in right inferior occipital gyrus have more severity of disease. The result demonstrated that the altered DC value in this region can probably be used to assess severity of ALS.

[Tanning lamp radiation-induced photochemical retinal damage].

PubMed

Volkov, V V; Kharitonova, N N; Mal'tsev, D S

2014-01-01

On the basis of original clinical research a rare case of bilateral retinal damage due to tanning lamp radiation exposure is presented. Along with significant decrease of visual acuity and light sensitivity of central visual field as well as color vision impairment, bilateral macular dystrophy was found during an ophthalmoscopy and confirmed by optical coherent tomography and fluorescent angiography. Intensive retinoprotective, vascular, and antioxidant therapy was effective and led to functional improvement and stabilization of the pathologic process associated with photochemical retinal damage. A brief review of literature compares mechanisms of retinal damage by either short or long-wave near visible radiation.

Comparison of visual outcomes after bilateral implantation of extended range of vision and trifocal intraocular lenses.

PubMed

Ruiz-Mesa, Ramón; Abengózar-Vela, Antonio; Aramburu, Ana; Ruiz-Santos, María

2017-06-26

To compare visual outcomes after cataract surgery with bilateral implantation of 2 intraocular lenses (IOLs): extended range of vision and trifocal. Each group of this prospective study comprised 40 eyes (20 patients). Phacoemulsification followed by bilateral implantation of a FineVision IOL (group 1) or a Symfony IOL (group 2) was performed. The following outcomes were assessed up to 1 year postoperatively: binocular uncorrected distance visual acuity (UDVA), binocular uncorrected intermediate visual acuity (UIVA) at 60 cm, binocular uncorrected near visual acuity (UNVA) at 40 cm, spherical equivalent (SE) refraction, defocus curves, mesopic and photopic contrast sensitivity, halometry, posterior capsule opacification (PCO), and responses to a patient questionnaire. The mean binocular values in group 1 and group 2, respectively, were SE -0.15 ± 0.25 D and -0.19 ± 0.18 D; UDVA 0.01 ± 0.03 logMAR and 0.01 ± 0.02 logMAR; UIVA 0.11 ± 0.08 logMAR and 0.09 ± 0.08 logMAR; UNVA 0.06 ± 0.07 logMAR and 0.17 ± 0.06 logMAR. Difference in UNVA between IOLs (p<0.05) was statistically significant. There were no significant differences in contrast sensitivity, halometry, or PCO between groups. Defocus curves were similar between groups from 0 D to -2 D, but showed significant differences from -2.50 D to -4.00 D (p<0.05). Both IOLs provided excellent distance and intermediate visual outcomes. The FineVision IOL showed better near visual acuity. Predictability of the refractive results and optical performance were excellent; all patients achieved spectacle independence. The 2 IOLs gave similar and good contrast sensitivity in photopic and mesopic conditions and low perception of halos by patients.

Reduced Misinformation Effects Following Saccadic Bilateral Eye Movements

ERIC Educational Resources Information Center

Parker, Andrew; Buckley, Sharon; Dagnall, Neil

2009-01-01

The effects of saccadic bilateral (horizontal) eye movements on memory for a visual event narrative were investigated. In the study phase, participants were exposed to a set of pictures accompanied by a verbal commentary describing the events depicted in the pictures. Next, the participants were asked either misleading or control questions about…

Visual and Analytical Strategies in Spatial Visualisation: Perspectives from Bilateral Symmetry and Reflection

ERIC Educational Resources Information Center

Ramful, Ajay; Ho, Siew Yin; Lowrie, Tom

2015-01-01

This inquiry presents two fine-grained case studies of students demonstrating different levels of cognitive functioning in relation to bilateral symmetry and reflection. The two students were asked to solve four sets of tasks and articulate their reasoning in task-based interviews. The first participant, Brittany, focused essentially on three…

Assessing the test-retest repeatability of the Vietnamese version of the National Eye Institute 25-item Visual Function Questionnaire among bilateral cataract patients for a Vietnamese population.

PubMed

To, Kien Gia; Meuleners, Lynn; Chen, Huei-Yang; Lee, Andy; Do, Dung Van; Duong, Dat Van; Phi, Tien Duy; Tran, Hoang Huy; Nguyen, Nguyen Do

2014-06-01

To determine the test-retest repeatability of the National Eye Institute 25-item Visual Function Questionnaire (NEI VFQ-25) for use with older Vietnamese adults with bilateral cataract. The questionnaire was translated into Vietnamese and back-translated into English by two independent translators. Patients with bilateral cataract aged 50 and older completed the questionnaire on two separate occasions, one to two weeks after first administration of the questionnaire. Test-retest repeatability was assessed using the Cronbach's α and intraclass correlation coefficients. The average age of participants was 67 ± 8 years and most participants were female (73%). Internal consistency was acceptable with the α coefficient above 0.7 for all subscales and intraclass correlation coefficients were 0.6 or greater in all subscales. The Vietnamese NEI VFQ-25 is reliable for use in studies assessing vision-related quality of life in older adults with bilateral cataract in Vietnam. We propose some modifications to the NEI-VFQ questions to reflect activities of older people in Vietnam. © 2013 ACOTA.

Infant Face Preferences after Binocular Visual Deprivation

ERIC Educational Resources Information Center

Mondloch, Catherine J.; Lewis, Terri L.; Levin, Alex V.; Maurer, Daphne

2013-01-01

Early visual deprivation impairs some, but not all, aspects of face perception. We investigated the possible developmental roots of later abnormalities by using a face detection task to test infants treated for bilateral congenital cataract within 1 hour of their first focused visual input. The seven patients were between 5 and 12 weeks old…

Superior parietal lobule dysfunction in a homogeneous group of dyslexic children with a visual attention span disorder.

PubMed

Peyrin, C; Démonet, J F; N'Guyen-Morel, M A; Le Bas, J F; Valdois, S

2011-09-01

A visual attention (VA) span disorder has been reported in dyslexic children as potentially responsible for their poor reading outcome. The purpose of the current paper was to identify the cerebral correlates of this VA span disorder. For this purpose, 12 French dyslexic children with severe reading and VA span disorders and 12 age-matched control children were engaged in a categorisation task under fMRI. Two flanked and isolated conditions were designed which both involved multiple-element simultaneous visual processing but taxed visual attention differently. For skilled readers, flanked stimuli processing activated a large bilateral cortical network comprising the superior and inferior parietal cortex, the inferior temporal cortex, the striate and extrastriate visual cortex, the middle frontal cortex and the anterior cingulate cortex while the less attention-demanding task of isolated stimuli only activated the inferior occipito-temporal cortex bilaterally. With respect to controls, the dyslexic children showed significantly reduced activation within bilateral parietal and temporal areas during flanked processing, but no difference during the isolated condition. The neural correlates of the processes involved in attention-demanding multi-element processing tasks were more specifically addressed by contrasting the flanked and the isolated conditions. This contrast elicited activation of the left precuneus/superior parietal lobule in the controls, but not in the dyslexic children. These findings provide new insights on the role of parietal regions, in particular the left superior parietal lobule, in the visual attention span and in developmental dyslexia. Copyright © 2010 Elsevier Inc. All rights reserved.

Ventral and dorsal streams processing visual motion perception (FDG-PET study)

PubMed Central

2012-01-01

Background Earlier functional imaging studies on visually induced self-motion perception (vection) disclosed a bilateral network of activations within primary and secondary visual cortex areas which was combined with signal decreases, i.e., deactivations, in multisensory vestibular cortex areas. This finding led to the concept of a reciprocal inhibitory interaction between the visual and vestibular systems. In order to define areas involved in special aspects of self-motion perception such as intensity and duration of the perceived circular vection (CV) or the amount of head tilt, correlation analyses of the regional cerebral glucose metabolism, rCGM (measured by fluorodeoxyglucose positron-emission tomography, FDG-PET) and these perceptual covariates were performed in 14 healthy volunteers. For analyses of the visual-vestibular interaction, the CV data were compared to a random dot motion stimulation condition (not inducing vection) and a control group at rest (no stimulation at all). Results Group subtraction analyses showed that the visual-vestibular interaction was modified during CV, i.e., the activations within the cerebellar vermis and parieto-occipital areas were enhanced. The correlation analysis between the rCGM and the intensity of visually induced vection, experienced as body tilt, showed a relationship for areas of the multisensory vestibular cortical network (inferior parietal lobule bilaterally, anterior cingulate gyrus), the medial parieto-occipital cortex, the frontal eye fields and the cerebellar vermis. The “earlier” multisensory vestibular areas like the parieto-insular vestibular cortex and the superior temporal gyrus did not appear in the latter analysis. The duration of perceived vection after stimulus stop was positively correlated with rCGM in medial temporal lobe areas bilaterally, which included the (para-)hippocampus, known to be involved in various aspects of memory processing. The amount of head tilt was found to be positively correlated with the rCGM of bilateral basal ganglia regions responsible for the control of motor function of the head. Conclusions Our data gave further insights into subfunctions within the complex cortical network involved in the processing of visual-vestibular interaction during CV. Specific areas of this cortical network could be attributed to the ventral stream (“what” pathway) responsible for the duration after stimulus stop and to the dorsal stream (“where/how” pathway) responsible for intensity aspects. PMID:22800430

High-Riding Congenital Hip Dislocation: THA With Unilateral vs Bilateral Transverse Femoral Shortening Osteotomy.

PubMed

Can, Ata; Sarikaya, Ilker A; Yontar, Necip S; Erdogan, Ayse O; Gorgun, Baris; Erdogan, Fahri

2018-05-01

We argue that 1-stage bilaterally total hip arthroplasty (THA) could be acceptable in bilateral coxarthrosis because of high-riding developmental dysplasia of the hip (DDH). Sixty-nine cases (51 patients) of high-riding DDH in patients who underwent THA from 2010 to 2013 were reviewed. Patients were divided into 2 groups: unilateral (group 1) and 1-stage bilateral surgery (group 2). The clinical measurements were the visual analog scale and Harris Hip Score. The average follow-up was 37.3 months for group 1 and 38.8 months for group 2. The hospital stay time was 5.2 days in group 1 and 6.2 days in group 2 (P = .334). The mean Harris Hip Score and visual analog scale score were improved significantly after surgery for both groups, and there was no statistically significant difference (P = .988). There was no difference between groups 1 and 2 in terms of complications (P = .137). Our data confirm that 1-stage bilateral transverse osteotomy with THA is an effective method as unilateral and it does not increase the length of patients' hospital stays and features a low risk of postoperative complications in the treatment of patients with high-riding DDH. Copyright © 2017 Elsevier Inc. All rights reserved.

Immediate sequential bilateral cataract surgery: A 5-year retrospective analysis of 2470 eyes from a tertiary care eye center in South India

PubMed Central

Ganesh, Sri; Brar, Sheetal; Sreenath, Rohit

2017-01-01

Purpose: The purpose of this study is to evaluate the safety and benefits of immediate sequential bilateral cataract surgery. Patients and Methods: Retrospective data analysis of patients who underwent immediate sequential bilateral phacoemulsification with foldable intraocular lens (IOL) implantation under topical anesthesia from January 2011 to September 2016 was performed. Patients with visually significant bilateral cataract within the axial length range of 21.0–26.5 mm were included in the study. Intraoperative and postoperative complications were evaluated. Results: Two thousand four hundred and seventy eyes from 1235 patients with a mean age of 68.34 years (range: 4–90 years) were analyzed. Best-corrected visual acuity improved from 0.40 ± 0.17 to 0.08 ± 0.10 (logarithm of the minimum angle of resolution). Nearly 92.05% eyes achieved a target postoperative refraction of ± 0.5 D spherical equivalent. Main complications observed were prolonged postoperative inflammation in 25% (n = 31), posterior capsular tears in 0.45% (n = 11), and unilateral cystoid macular edema in 0.08% (n = 2) eyes. No sight-threatening complications such as endophthalmitis, retinal detachment, corneal decompensation and intraocular hemorrhage occurred in any of the eyes. Out of the 288 (23.2%) patients who underwent bilateral multifocal IOL implantation, 23 patients (46 eyes) had femtolaser-assisted cataract surgery procedure. Two pediatric and one Downs syndrome patient underwent bilateral cataract surgery under general anesthesia and intravenous sedation, respectively. Conclusion: IBSCS may be considered as a preferred practice in eligible cases considering significant patient benefits such as early visual rehabilitation, time and cost-effectiveness, and better compliance with postoperative medications. In debilitated patients and special situations, such as pediatric cataract and Downs syndrome requiring general anesthesia it may be the ideal procedure. PMID:28573990

Impaired force control in writer's cramp showing a bilateral deficit in sensorimotor integration.

PubMed

Bleton, Jean-Pierre; Teremetz, Maxime; Vidailhet, Marie; Mesure, Serge; Maier, Marc A; Lindberg, Påvel G

2014-01-01

Abnormal cortical processing of sensory inputs has been found bilaterally in writer's cramp (WC). This study tested the hypothesis that patients with WC have an impaired ability to adjust grip forces according to visual and somatosensory cues in both hands. A unimanual visuomotor force-tracking task and a bimanual sense of effort force-matching task were performed by WC patients and healthy controls. In visuomotor tracking, WC patients showed increased error, greater variability, and longer release duration than controls. In the force-matching task, patients underestimated, whereas controls overestimated, the force applied in the other hand. Visuomotor tracking and force matching were equally impaired in both the symptomatic and nonsymptomatic hand in WC patients. This study provides evidence of bilaterally impaired grip-force control in WC, when using visual or sense of effort cues. This suggests a generalized subclinical deficit in sensorimotor integration in WC. Copyright © 2013 Movement Disorder Society.

Clinical Outcomes after Binocular Implantation of a New Trifocal Diffractive Intraocular Lens

PubMed Central

Kretz, Florian T. A.; Breyer, Detlev; Diakonis, Vasilios F.; Klabe, Karsten; Henke, Franziska; Auffarth, Gerd U.; Kaymak, Hakan

2015-01-01

Purpose. To evaluate visual, refractive, and contrast sensitivity outcomes, as well as the incidence of pseudophakic photic phenomena and patient satisfaction after bilateral diffractive trifocal intraocular lens (IOL) implantation. Methods. This prospective nonrandomized study included consecutive patients undergoing cataract surgery with bilateral implantation of a diffractive trifocal IOL (AT LISA tri 839MP, Carl Zeiss Meditec). Distance, intermediate, and near visual outcomes were evaluated as well as the defocus curve and the refractive outcomes 3 months after surgery. Photopic and mesopic contrast sensitivity, patient satisfaction, and halo perception were also evaluated. Results. Seventy-six eyes of 38 patients were included; 90% of eyes showed a spherical equivalent within ±0.50 diopters 3 months after surgery. All patients had a binocular uncorrected distance visual acuity of 0.00 LogMAR or better and a binocular uncorrected intermediate visual acuity of 0.10 LogMAR or better, 3 months after surgery. Furthermore, 85% of patients achieved a binocular uncorrected near visual acuity of 0.10 LogMAR or better. Conclusions. Trifocal diffractive IOL implantation seems to provide an effective restoration of visual function for far, intermediate, and near distances, providing high levels of visual quality and patient satisfaction. PMID:26301104

Quality of vision, patient satisfaction and long-term visual function after bilateral implantation of a low addition multifocal intraocular lens.

PubMed

Pedrotti, Emilio; Mastropasqua, Rodolfo; Bonetto, Jacopo; Demasi, Christian; Aiello, Francesco; Nucci, Carlo; Mariotti, Cesare; Marchini, Giorgio

2017-07-17

The aim of the current study was to compare the quality of vision, contrast sensitivity and patient satisfaction with a biaspheric, segmented, rotationally asymmetric IOL (Lentis Comfort LS-313 MF 15-Oculentis GmbH, Berlin, Germany) as opposed to those of a monofocal IOL. This prospective single-blind comparative study included two groups of patients affected by bilateral senile cataract who underwent lens extraction and IOL implantation. The first group received a bilateral implantation of a monofocal IOL, and the second group received a bilateral implantation of the Comfort IOL. Twelve months after surgery uncorrected and corrected visual acuity at different distances (30, 50, 70 cm and 4 m), defocus curve and contrast sensitivity were assessed. Patient's satisfaction and spectacle independence were evaluated by mean of the NEI RQL-42 questionnaire. No significant differences were found between the groups in terms of near vision. The group of patients implanted with a Comfort IOL obtained the best results at intermediate distances (50 and 70 cm P < .001). Both groups showed an excellent uncorrected distance visual acuity (4 m). No statistically significant differences were found in terms of corrected near, intermediate and distance visual acuity. Concerning contrast sensitivity, no statistically significant differences between the groups were observed at any cycles per degree. The NEI RQL-42 questionnaire showed statistically significant differences between the group for "near vision" (P = .015), "dependence on correction" (P = .048) and "suboptimal correction" (P < .001) subscales. Our findings indicated that the Comfort IOL +1.5 D provides a good intermediate spectacle independence together with a high quality of vision, with a low amount of subjective symptoms and a contrast sensitivity similar to those obtained with a monofocal IOL.

Bilateral symmetry in vision and influence of ocular surgical procedures on binocular vision: A topical review.

PubMed

Arba Mosquera, Samuel; Verma, Shwetabh

2016-01-01

We analyze the role of bilateral symmetry in enhancing binocular visual ability in human eyes, and further explore how efficiently bilateral symmetry is preserved in different ocular surgical procedures. The inclusion criterion for this review was strict relevance to the clinical questions under research. Enantiomorphism has been reported in lower order aberrations, higher order aberrations and cone directionality. When contrast differs in the two eyes, binocular acuity is better than monocular acuity of the eye that receives higher contrast. Anisometropia has an uncommon occurrence in large populations. Anisometropia seen in infancy and childhood is transitory and of little consequence for the visual acuity. Binocular summation of contrast signals declines with age, independent of inter-ocular differences. The symmetric associations between the right and left eye could be explained by the symmetry in pupil offset and visual axis which is always nasal in both eyes. Binocular summation mitigates poor visual performance under low luminance conditions and strong inter-ocular disparity detrimentally affects binocular summation. Considerable symmetry of response exists in fellow eyes of patients undergoing myopic PRK and LASIK, however the method to determine whether or not symmetry is maintained consist of comparing individual terms in a variety of ad hoc ways both before and after the refractive surgery, ignoring the fact that retinal image quality for any individual is based on the sum of all terms. The analysis of bilateral symmetry should be related to the patients' binocular vision status. The role of aberrations in monocular and binocular vision needs further investigation. Copyright © 2016 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

Cerebellar Ataxia with Bilateral Vestibulopathy: Description of a Syndrome and Its Characteristic Clinical Sign

ERIC Educational Resources Information Center

Migliaccio, Americo A.; Halmagyi, G. Michael; McGarvie, Leigh A.; Cremer, Phillip D.

2004-01-01

We report four patients with the syndrome of cerebellar ataxia with bilateral vestibulopathy (CABV) and, using search coil oculography, we validate its characteristic clinical sign, namely impairment of the visually enhanced vestibulo-ocular reflex (VVOR) or doll's head reflex. In our four patients, CABV began in the sixth decade of life; they are…

Bilateral Posterior Scleritis Associated with Giant Cell Arteritis: A Case Report.

PubMed

Erdogan, Mehmet; Sayin, Nihat; Yıldız Ekinci, Dilbade; Bayramoglu, Sadik

2017-09-15

To report a case of bilateral posterior scleritis associated with giant cell arteritis Case Report: A 62-year-old female patient presented with bilateral progressive vision loss was diagnosed with bilateral posterior scleritis. According to clinical signs and symptoms and laboratory testing, Giant cell arteritis was also diagnosed. Within 8 weeks of the corticosteroid treatment, the serous retinal detachments completely resolved and choroidal thickness decreased in both eyes. Visual acuity increased, and the symtoms related to Giant cell arteritis improved. Posterior scleritis is an inflammatory disease that may be associated with many autoimmune systemic diseases. GCA should be thought of particularly in patients over the age of 50 with bilateral involvement, and a relevant detailed history should be obtained for early and correct diagnosis and treatment.

A Sticky Situation.

PubMed

Weng, Christina Y; Khimani, Karima S; Foroozan, Rod; Gospe, Sidney M; Bhatti, M Tariq

2018-04-26

An 81-year-old man with bilateral progressively blurry vision and optic disc swelling was referred for evaluation. Examination and ancillary testing confirmed a diagnosis of bilateral vitreopapillary traction (VPT) accompanied by unilateral tractional retinoschisis in the right eye. Pars plana vitrectomy was performed to release the traction in both eyes. Visual acuity improved in the right eye and stabilized in the left eye. Retinoschisis in the right eye resolved. The visual field improved in both eyes, although the left eye demonstrated a persistent hemifield defect likely attributable to a prior optic neuropathy. Distinguishing VPT optic neuropathy (VPTON) from nonarteritic anterior ischemic optic neuropathy (NAION) is discussed. Copyright © 2018 Elsevier Inc. All rights reserved.

Survey of childhood blindness and visual impairment in Botswana.

PubMed

Nallasamy, Sudha; Anninger, William V; Quinn, Graham E; Kroener, Brian; Zetola, Nicola M; Nkomazana, Oathokwa

2011-10-01

In terms of blind-person years, the worldwide burden of childhood blindness is second only to cataracts. In many developing countries, 30-72% of childhood blindness is avoidable. The authors conducted this study to determine the causes of childhood blindness and visual impairment (VI) in Botswana, a middle-income country with limited access to ophthalmic care. This study was conducted over 4 weeks in eight cities and villages in Botswana. Children were recruited through a radio advertisement and local outreach programmes. Those ≤ 15 years of age with visual acuity <6/18 in either eye were enrolled. The WHO/Prevention of Blindness Eye Examination Record for Children with Blindness and Low Vision was used to record data. The authors enrolled 241 children, 79 with unilateral and 162 with bilateral VI. Of unilateral cases, 89% were avoidable: 23% preventable (83% trauma-related) and 66% treatable (40% refractive error and 31% amblyopia). Of bilateral cases, 63% were avoidable: 5% preventable and 58% treatable (33% refractive error and 31% congenital cataracts). Refractive error, which is easily correctable with glasses, is the most common cause of bilateral VI, with cataracts a close second. A nationwide intervention is currently being planned to reduce the burden of avoidable childhood VI in Botswana.

Bilateral vision loss due to Leber's hereditary optic neuropathy after long-term alcohol, nicotine and drug abuse.

PubMed

Maass, Johanna; Matthé, Egbert

2018-04-01

Leber's hereditary optic neuropathy is relatively rare, and no clinical pathognomonic signs exist. We present a rare case of bilateral vision loss of a patient with multiple drug abuse in the history. A 31-year-old man presented with a history of progressive, decreased vision in both eyes for 6 month. On examination, his visual acuity was hand motion in both eyes. Funduscopy demonstrated a temporal pallor of the optic disc. Goldmann visual field perimetry showed a crescent visual field in the right eye and a circular decrease to less than 50 ° in the left eye. Electroretinogram showed a scotopic b-wave amplitude reduction. Optical coherence tomographies, Heidelberg Retina tomography, visual evoked potentials, and magnetic resonance imaging with contrast as well as blood tests were normal. The patient reported to consume various kinds of drugs as well as recreational drug use and alcohol consumption since he was 16 years old. We started a hemodilution therapy, believing the patient suffered from a bilateral, toxic optic neuropathy due to his lifestyle. Laboratory results later on showed Leber's hereditary optic neuropathy. Leber's hereditary optic neuropathy is a rare disease without a typical, pathognomonic presentation. Even though the patient gave good reasons for a toxic optic neuropathy, one should never stop to test for other diseases.

Bilateral Traumatic Globe Luxation with Optic Nerve Transection

PubMed Central

Tok, Levent; Tok, Ozlem Yalcin; Argun, Tugba Cakmak; Yilmaz, Omer; Gunes, Alime; Unlu, Elif Nisa; Sezer, Sezgin; Ibisoglu, Seda; Argun, Mehmet

2014-01-01

Purpose The purpose of this study was to document clinical findings and management of a patient with bilateral globe luxation and optic nerve transection. Materials and Methods A 25-year-old female patient was admitted to the emergency department with bilateral traumatic globe luxation following a motor vehicle accident. Results Visual acuity testing showed no light perception. The right pupil was dilated and bilaterally did not react to light. The globes were bilaterally intact. A computed tomography scan revealed Le Fort type II fractures, bilateral optic nerve transection and disruption of all extraocular muscles. The globes of the patient were bilaterally reduced into the orbit. However, the patient developed phthisis bulbi in the right eye at month 3. Conclusion Globe luxation presents a dramatic clinical picture, and may lead to the development of severe complications due to the concomitance of complete optic nerve dissection and multiple traumas. Even if the luxated globe is repositioned into the orbit, there is still an increased risk of the development of phthisis due to ischemia. PMID:25606034

Visual acuity and contrast sensitivity are two important factors affecting vision-related quality of life in advanced age-related macular degeneration

PubMed Central

Selivanova, Alexandra; Shin, Hyun Joon; Miller, Joan W.; Jackson, Mary Lou

2018-01-01

Purpose Vision loss from age-related macular degeneration (AMD) has a profound effect on vision-related quality of life (VRQoL). The pupose of this study is to identify clinical factors associated with VRQoL using the Rasch- calibrated NEI VFQ-25 scales in bilateral advanced AMD patients. Methods We retrospectively reviewed 47 patients (mean age 83.2 years) with bilateral advanced AMD. Clinical assessment included age, gender, type of AMD, high contrast visual acuity (VA), history of medical conditions, contrast sensitivity (CS), central visual field loss, report of Charles Bonnet Syndrome, current treatment for AMD and Rasch-calibrated NEI VFQ-25 visual function and socioemotional function scales. The NEI VFQ visual function scale includes items of general vision, peripheral vision, distance vision and near vision-related activity while the socioemotional function scale includes items of vision related-social functioning, role difficulties, dependency, and mental health. Multiple regression analysis (structural regression model) was performed using fixed item parameters obtained from the one-parameter item response theory model. Results Multivariate analysis showed that high contrast VA and CS were two factors influencing VRQoL visual function scale (β = -0.25, 95% CI-0.37 to -0.12, p<0.001 and β = 0.35, 95% CI 0.25 to 0.46, p<0.001) and socioemontional functioning scale (β = -0.2, 95% CI -0.37 to -0.03, p = 0.023, and β = 0.3, 95% CI 0.18 to 0.43, p = 0.001). Central visual field loss was not assoicated with either VRQoL visual or socioemontional functioning scale (β = -0.08, 95% CI-0.28 to 0.12,p = 0.44 and β = -0.09, 95% CI -0.03 to 0.16, p = 0.50, respectively). Conclusion In patients with vision impairment secondary to bilateral advanced AMD, high contrast VA and CS are two important factors affecting VRQoL. PMID:29746512

Long-term visual outcomes and patient satisfaction following bilateral implantation of trifocal intraocular lenses

PubMed Central

Ganesh, Sri; Brar, Sheetal; Pawar, Archana

2017-01-01

Purpose To study the long-term visual and refractive outcomes and evaluate patient satisfaction after bilateral implantation of trifocal intraocular lenses (IOLs). Setting Nethradhama Superspeciality Eye Hospital, Bangalore. Design Prospective, nonrandomized study. Methods Eligible patients undergoing bilateral phacoemulsification with trifocal IOL implantation were included. Follow-up examinations were conducted at day 1, 1 week, 1 month, 6 months, and 12 months. Postoperatively, 1 month onward evaluation of uncorrected and distance-corrected far and near visual acuity; reading acuity and reading speeds (using Salzburg Reading Desk) at 70, 80, and 90 cm; contrast sensitivity; defocus curves; and patient satisfaction was carried out. Results Fifty eyes from 25 patients with a mean age of 58±13.44 years were included. All eyes showed significant improvement in spherical equivalent, uncorrected distance visual acuity, corrected distance visual acuity, uncorrected near visual acuity, and corrected near visual acuity at 1 month compared to preoperative values (P<0.05), with no significant change in these parameters thereafter until the last follow-up (P>0.05). At 12 months, mean uncorrected reading acuities and reading speeds at 70, 80, and 90 cm were in the range of 0.09–0.04 logMAR units and 153.6–169.0 words per minute, respectively, with significantly better results at 80 cm. Five eyes underwent YAG laser capsulotomy for early posterior capsule opacification (PCO) at a mean follow-up of 7.2±2.9 months. Contrast sensitivity scores at 12 months were comparable to 1 month (P>0.05 for all spatial frequencies). All patients reported good tolerance and 100% independence from spectacles for all activities. Conclusion Trifocal IOLs provided excellent unaided vision at all distances. Reading performance was good through the complete intermediate distance range. PCO occurrence and subsequent YAG capsulotomy did not affect the long-term visual outcomes. PMID:28860693

Visual acuity and contrast sensitivity are two important factors affecting vision-related quality of life in advanced age-related macular degeneration.

PubMed

Roh, Miin; Selivanova, Alexandra; Shin, Hyun Joon; Miller, Joan W; Jackson, Mary Lou

2018-01-01

Vision loss from age-related macular degeneration (AMD) has a profound effect on vision-related quality of life (VRQoL). The pupose of this study is to identify clinical factors associated with VRQoL using the Rasch- calibrated NEI VFQ-25 scales in bilateral advanced AMD patients. We retrospectively reviewed 47 patients (mean age 83.2 years) with bilateral advanced AMD. Clinical assessment included age, gender, type of AMD, high contrast visual acuity (VA), history of medical conditions, contrast sensitivity (CS), central visual field loss, report of Charles Bonnet Syndrome, current treatment for AMD and Rasch-calibrated NEI VFQ-25 visual function and socioemotional function scales. The NEI VFQ visual function scale includes items of general vision, peripheral vision, distance vision and near vision-related activity while the socioemotional function scale includes items of vision related-social functioning, role difficulties, dependency, and mental health. Multiple regression analysis (structural regression model) was performed using fixed item parameters obtained from the one-parameter item response theory model. Multivariate analysis showed that high contrast VA and CS were two factors influencing VRQoL visual function scale (β = -0.25, 95% CI-0.37 to -0.12, p<0.001 and β = 0.35, 95% CI 0.25 to 0.46, p<0.001) and socioemontional functioning scale (β = -0.2, 95% CI -0.37 to -0.03, p = 0.023, and β = 0.3, 95% CI 0.18 to 0.43, p = 0.001). Central visual field loss was not assoicated with either VRQoL visual or socioemontional functioning scale (β = -0.08, 95% CI-0.28 to 0.12,p = 0.44 and β = -0.09, 95% CI -0.03 to 0.16, p = 0.50, respectively). In patients with vision impairment secondary to bilateral advanced AMD, high contrast VA and CS are two important factors affecting VRQoL.

Functional and structural comparison of visual lateralization in birds – similar but still different

PubMed Central

Ströckens, Felix

2014-01-01

Vertebrate brains display physiological and anatomical left-right differences, which are related to hemispheric dominances for specific functions. Functional lateralizations likely rely on structural left-right differences in intra- and interhemispheric connectivity patterns that develop in tight gene-environment interactions. The visual systems of chickens and pigeons show that asymmetrical light stimulation during ontogeny induces a dominance of the left hemisphere for visuomotor control that is paralleled by projection asymmetries within the ascending visual pathways. But structural asymmetries vary essentially between both species concerning the affected pathway (thalamo- vs. tectofugal system), constancy of effects (transient vs. permanent), and the hemisphere receiving stronger bilateral input (right vs. left). These discrepancies suggest that at least two aspects of visual processes are influenced by asymmetric light stimulation: (1) visuomotor dominance develops within the ontogenetically stronger stimulated hemisphere but not necessarily in the one receiving stronger bottom-up input. As a secondary consequence of asymmetrical light experience, lateralized top-down mechanisms play a critical role in the emergence of hemispheric dominance. (2) Ontogenetic light experiences may affect the dominant use of left- and right-hemispheric strategies. Evidences from social and spatial cognition tasks indicate that chickens rely more on a right-hemispheric global strategy whereas pigeons display a dominance of the left hemisphere. Thus, behavioral asymmetries are linked to a stronger bilateral input to the right hemisphere in chickens but to the left one in pigeons. The degree of bilateral visual input may determine the dominant visual processing strategy when redundant encoding is possible. This analysis supports that environmental stimulation affects the balance between hemispheric-specific processing by lateralized interactions of bottom-up and top-down systems. PMID:24723898

Clinical outcome and higher order aberrations after bilateral implantation of an extended depth of focus intraocular lens.

PubMed

Pilger, Daniel; Homburg, David; Brockmann, Tobias; Torun, Necip; Bertelmann, Eckart; von Sonnleithner, Christoph

2018-04-01

The purpose of this study was to assess the clinical outcome after a bilateral implantation of an extended depth of focus intraocular lens in comparison to a monofocal intraocular lens. Department of Ophthalmology, Charité-Medical University Berlin, Germany. A total of 60 eyes of 30 patients were enrolled in this prospective, single-center study. The cataract patients underwent phacoemulsification with bilateral implantation of a TECNIS ® Symfony (Abbott Medical Optics, Santa Ana, CA, USA, 15 patients) or a TECNIS Monofocal ZCB00 (Abbott Medical Optics, Santa Ana, CA, USA, 15 patients). Postoperative evaluations were performed after 1 and 3 months, including visual acuities at far, intermediate, and near distance. Mesopic, scotopic vision, and contrast sensitivity were investigated. Aberrometry was performed using an iTrace aberrometer with a pupil scan size of 5.0 mm. After 3 months, the TECNIS Symfony group reached an uncorrected visual acuity at far distance of -0.02 logMAR compared to -0.06 logMAR in the TECNIS Monofocal group ( p = 0.03). Regarding the uncorrected vision at intermediate and near distance the following values were obtained: intermediate visual acuity -0.13 versus 0.0 logMAR (TECNIS Symfony vs TECNIS Monofocal, p = 0.001) and near visual acuity 0.11 versus 0.26 logMAR (TECNIS Symfony vs TECNIS Monofocal, p = 0.001). Low-contrast visual acuities were 0.27 versus 0.20 logMar (TECNIS Symfony vs TECNIS Monofocal, p = 0.023). The TECNIS Symfony intraocular lens can be considered an appropriate alternative to multifocal intraocular lenses because of good visual results at far, intermediate, and near distance as well as in low-contrast vision.

Comparison of Visual Performance of Multifocal Intraocular Lenses with Same Material Monofocal Intraocular Lenses

PubMed Central

Yamauchi, Tomofusa; Tabuchi, Hitoshi; Takase, Kosuke; Ohsugi, Hideharu; Ohara, Zaigen; Kiuchi, Yoshiaki

2013-01-01

Purpose To compare the visual performance of multifocal intraocular lenses (IOLs) and monofocal IOLs made of the same material. Methods The subjects included patients implanted with either Tecnis® monofocal IOLs (ZA9003 or ZCB00) or Tecnis® multifocal IOLs (ZMA00 or ZMB00) bilaterally. We conducted a retrospective study comparing the two types of IOLs. The multifocal group included 46 patients who were implanted with Tecnis® multifocal IOLs bilaterally. The monofocal group was an age- and sex-matched control group, and included 85 patients who were implanted with Tecnis® monofocal IOLs bilaterally. Lens opacity grading, the radius of corneal curvature, corneal astigmatism, axial length and the refractive status were measured preoperatively. Pupil size, ocular aberrometry, distance, intermediate and near visual acuity, contrast sensitivity with and without glare and the responses to a quality-of-vision questionnaire were evaluated pre- and postoperatively. Results The uncorrected near visual acuity was significantly better in the multifocal group, whereas both the corrected intermediate and near visual acuity were better in the monofocal group. Contrast sensitivity (with and without glare) was significantly better in the monofocal group. The rate of spectacle dependency was significantly lower in the multifocal group. There were no significant differences between the two groups regarding most items of the postoperative quality-of-vision questionnaire (VFQ-25), with the exception that the patients in the monofocal group reported fewer problems with nighttime driving. Conclusions The multifocal IOLs used in this study reduced spectacle dependency more so than monofocal IOLs and did not compromise the subjective visual function, with the exception of nighttime driving. PMID:23840836

The effects of bilateral presentations on lateralized lexical decision.

PubMed

Fernandino, Leonardo; Iacoboni, Marco; Zaidel, Eran

2007-06-01

We investigated how lateralized lexical decision is affected by the presence of distractors in the visual hemifield contralateral to the target. The study had three goals: first, to determine how the presence of a distractor (either a word or a pseudoword) affects visual field differences in the processing of the target; second, to identify the stage of the process in which the distractor is affecting the decision about the target; and third, to determine whether the interaction between the lexicality of the target and the lexicality of the distractor ("lexical redundancy effect") is due to facilitation or inhibition of lexical processing. Unilateral and bilateral trials were presented in separate blocks. Target stimuli were always underlined. Regarding our first goal, we found that bilateral presentations (a) increased the effect of visual hemifield of presentation (right visual field advantage) for words by slowing down the processing of word targets presented to the left visual field, and (b) produced an interaction between visual hemifield of presentation (VF) and target lexicality (TLex), which implies the use of different strategies by the two hemispheres in lexical processing. For our second goal of determining the processing stage that is affected by the distractor, we introduced a third condition in which targets were always accompanied by "perceptual" distractors consisting of sequences of the letter "x" (e.g., xxxx). Performance on these trials indicated that most of the interaction occurs during lexical access (after basic perceptual analysis but before response programming). Finally, a comparison between performance patterns on the trials containing perceptual and lexical distractors indicated that the lexical redundancy effect is mainly due to inhibition of word processing by pseudoword distractors.

Inducing comprehension in the bilateral poor reader.

PubMed

Rattan, G; Dean, R S; Lowrie, R E

1987-09-01

The comprehension effects of changes in the spatial configuration of prose were examined with reading disabled children who differed in laterality preference. Specifically, 24 learning disabled boys were presented with prose materials in a standard, phrased, and backward (right to left) fashion. Measures of comprehension showed that text in the phrased and backward conditions differentially facilitated comprehension for the more bilateral subjects but had little effect on more right lateralized subjects. The results were discussed in terms of the instructional implications of alterations in the visual-spatial arrangement of prose materials for bilateral readers.

Bilateral panuveitis associated with Whipple disease - case report.

PubMed

Lisboa, Maria; Domingues, Isabel; Pamplona, Jaime; Barata, Pedro; Morgado, Joana; Brotas, Vítor

2014-01-01

To describe a clinical case and literature review of Whipple disease. A 65-year-old male with bilateral decreased visual acuity for 3 weeks as well as bilateral hypoacusia, vertigo, disequilibrium, headache and decreased strength in the right upper limb for 4 months. The clinical work-up revealed a bilateral panuveitis and an ischemic cerebellar stroke. The diagnosis of Whipple disease was confirmed by histopathological analysis of adenopathy. The patient was treated with cortico-antibiotic therapy with significant clinical improvement. Although rare, Whipple disease is potentially fatal if left untreated, it must be always be taken into consideration before any panuveitis of an unknown cause, even in the absence of gastrointestinal symptoms.

Hippocampus Contributes to the Maintenance but Not the Quality of Visual Information over Time

ERIC Educational Resources Information Center

Warren, David E.; Duff, Melissa C.; Cohen, Neal J.; Tranel, Daniel

2015-01-01

The hippocampus has recently been implicated in the brief representation of visual information, but its specific role is not well understood. We investigated this role using a paradigm that distinguishes quantity and quality of visual memory as described in a previous study. We found that amnesic patients with bilateral hippocampal damage (N = 5)…

Familial History of Reading Difficulty Is Associated with Diffused Bilateral Brain Activation during Reading and Greater Association with Visual Attention Abilities

ERIC Educational Resources Information Center

Horowitz-Kraus, Tzipi

2017-01-01

Reading difficulty (RD; or dyslexia) is a heritable condition characterized by slow, inaccurate reading accompanied by executive dysfunction, specifically with respect to visual attention. The current study was designed to examine the effect of familial history of RD on the relationship between reading and visual attention abilities in children…

Serial functional imaging poststroke reveals visual cortex reorganization.

PubMed

Brodtmann, Amy; Puce, Aina; Darby, David; Donnan, Geoffrey

2009-02-01

Visual cortical reorganization following injury remains poorly understood. The authors performed serial functional magnetic resonance imaging (fMRI) on patients with visual cortex infarction to evaluate early and late striate, ventral, and dorsal extrastriate cortical activation. Patients were studied with fMRI within 10 days and at 6 months. The authors used a high-level visual activation task designed to activate the ventral extrastriate cortex. These data were compared to those of age-appropriate healthy control participants. The results from 24 healthy control individuals (mean age 65.7 +/- SE 3.6 years, range 32-89) were compared to those from 5 stroke patients (mean age 73.8 +/- SE 7 years, range 49-86). Patients had infarcts involving the striate and ventral extrastriate cortex. Patient activation patterns were markedly different to controls. Bilateral striate and ventral extrastriate activation was reduced at both sessions, but dorsal extrastriate activated voxel counts remained comparable to controls. Conversely, mean percent magnetic resonance signal change increased in dorsal sites. These data provide strong evidence of bilateral poststroke functional depression of striate and ventral extrastriate cortices. Possible utilization or surrogacy of the dorsal visual system was demonstrated following stroke. This activity could provide a target for novel visual rehabilitation therapies.

Return of visual function after bilateral visual loss following flow diversion embolization of a giant ophthalmic aneurysm due to both reduction in mass effect and reduction in aneurysm pulsation.

PubMed

Patel, Saharsh; Fargen, Kyle M; Peters, Keith; Krall, Peter; Samy, Hazem; Hoh, Brian L

2015-01-01

Large and giant paraclinoid aneurysms are challenging to treat by either surgical or endovascular means. Visual dysfunction secondary to optic nerve compression and its relationship with aneurysm size, pulsation and thrombosis is poorly understood. We present a patient with a giant paraclinoid aneurysm resulting in bilateral visual loss that worsened following placement of a Pipeline Embolization Device and adjunctive coiling. Visual worsening occurred in conjunction with aneurysm thrombosis, increase in maximal aneurysm diameter and new adjacent edema. Her visual function spontaneously improved in a delayed fashion to better than pre-procedure, in conjunction with reduced aneurysmal mass effect, size and pulsation artifact on MRI. This report documents detailed ophthalmologic and MRI evidence for the role of thrombosis, aneurysm mass effect and aneurysm pulsation as causative etiologies for both cranial nerve dysfunction and delayed resolution following flow diversion treatment of large cerebral aneurysms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

NEAR-INFRARED AUTOFLUORESCENCE IN BILATERAL DIFFUSE UVEAL MELANOCYTIC PROLIFERATION ASSOCIATED WITH ESOPHAGEAL CARCINOMA AND CHOROIDAL METASTASIS.

PubMed

Golshahi, Azadeh; Bornfeld, Norbert; Weinitz, Silke; Kellner, Ulrich

2016-01-01

To investigate the advantage of near-infrared autofluorescence (787 nm) for the detection of melanocytic lesions in a patient with bilateral diffuse uveal melanocytic proliferation in association with esophageal carcinoma complicated by most likely unilateral choroidal metastasis. In this retrospective case report, a 55-year-old woman referred for the evaluation of sudden visual loss underwent normal ophthalmological evaluation and, in addition, was examined with near-infrared reflectance, near-infrared autofluorescence, fundus autofluorescence (Heidelberg Retina Angiograph II [HRA2; Heidelberg Engineering]), spectral domain optical coherence tomography (Spectralis OCT; Heidelberg Engineering), and multifocal electroretinography (RetiScan; Roland Consult). The patient had been diagnosed with esophageal carcinoma 3 months before the onset of visual symptoms. The visual acuity was 20/40 in the right eye and 20/20 in the left eye. Bilateral patchy melanocytic proliferation was detected on ophthalmoscopy. The extent of lesions was best detected with near-infrared reflectance and near-infrared autofluorescence, whereas fundus autofluorescence and spectral domain optical coherence tomography did not reveal alterations of the outer retina or retinal pigment epithelium in this early stage of bilateral diffuse uveal melanocytic proliferation. The right eye showed in addition to the findings on the left eye choroidal folds in the fovea and an elevated lesion inferotemporal of the fovea suspicious of a choroidal metastasis. In the B-scan ultrasonography, a homogenous lesion was seen. Spectral domain optical coherence tomography demonstrated a mild accumulation of subretinal fluid adjacent to and over the choroidal metastasis. Transretinal biopsy of this elevated lesion revealed a low differentiated carcinoma of squamous epithelium, compatible with choroidal metastasis of the esophageal carcinoma. The choroidal metastasis increased within 3 months after the first visit. The visual acuity dropped in both eyes. The patient died 6 months after her first visit. Bilateral diffuse uveal melanocytic proliferation can be associated with esophageal carcinoma as a systemic malignancy. Near-infrared imaging can be helpful to detect early stages of BDUMP and can help offer recently reported treatment options at an early stage of disease.

Related visual impairment to mother-infant interaction and development in infants with bilateral retinoblastoma.

PubMed

Nagayoshi, Michie; Hirose, Taiko; Toju, Kyoko; Suzuki, Shigenobu; Okamitsu, Motoko; Teramoto, Taeko; Omori, Takahide; Kawamura, Aki; Takeo, Naoko

2017-06-01

This study was conducted with infants diagnosed with bilateral retinoblastoma (RB) and their mothers. It explored characteristics of the mother-infant interaction, the infants' developmental characteristics and related risk factors. Cross-sectional statistical analysis was performed with 18 dyads of one-year-old infants with bilateral RB and their mothers. Using the Japanese Nursing Child Assessment Teaching Scale (JNCATS) results showed that infants with RB had significantly lower scores compared to normative Japanese scores on all of the infants' subscales and "Child's contingency" (p < 0.01). Five infants with visual impairment at high risk of developmental problems had a pass rate of 0% on six JNCATS items. There were positive correlations between Developmental quotients (DQ) and JNCATS score of "Responsiveness to caregiver" (ρ = 0.50, p < 0.05) and DQ and "Child's contingency" (ρ = 0.47, p < 0.05). Infants with visual impairment were characterized by high likelihood of developmental delays and problematic behaviors; they tended not to turn their face or eyes toward their mothers, smile in response to their mothers' talking to them or the latter's changing body language or facial expressions, or react in a contingent manner in their interactions. These infant behaviors noted by their mothers shared similarities with developmental characteristics of children with visual impairments. These findings indicated a need to provide support promoting mother-infant interactions consistent with the developmental characteristics of RB infants with visual impairment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Visual loss in Takayasu Arteritis - Look Beyond the Eye.

PubMed

Peter, Jayanthi; Joseph, George; Mathew, Vivek; Peter, John Victor

2014-08-01

Patients with Takayasu arteritis often present with reduced vision related either to the disease per se or due to complications of therapy. We report a patient with Takayasu arteritis who developed acute onset bilateral visual loss 6wks following percutaneous revascularization of occluded aortic arch branches. No ocular cause for the visual loss was evident. The reason for visual loss in this patient was an extraocular cause. Ocular and extraocular causes of visual loss in Takayasu arteritis are discussed.

Common neural substrates for visual working memory and attention.

PubMed

Mayer, Jutta S; Bittner, Robert A; Nikolić, Danko; Bledowski, Christoph; Goebel, Rainer; Linden, David E J

2007-06-01

Humans are severely limited in their ability to memorize visual information over short periods of time. Selective attention has been implicated as a limiting factor. Here we used functional magnetic resonance imaging to test the hypothesis that this limitation is due to common neural resources shared by visual working memory (WM) and selective attention. We combined visual search and delayed discrimination of complex objects and independently modulated the demands on selective attention and WM encoding. Participants were presented with a search array and performed easy or difficult visual search in order to encode one or three complex objects into visual WM. Overlapping activation for attention-demanding visual search and WM encoding was observed in distributed posterior and frontal regions. In the right prefrontal cortex and bilateral insula blood oxygen-level-dependent activation additively increased with increased WM load and attentional demand. Conversely, several visual, parietal and premotor areas showed overlapping activation for the two task components and were severely reduced in their WM load response under the condition with high attentional demand. Regions in the left prefrontal cortex were selectively responsive to WM load. Areas selectively responsive to high attentional demand were found within the right prefrontal and bilateral occipital cortex. These results indicate that encoding into visual WM and visual selective attention require to a high degree access to common neural resources. We propose that competition for resources shared by visual attention and WM encoding can limit processing capabilities in distributed posterior brain regions.

Lifetime risk of blindness in open-angle glaucoma.

PubMed

Peters, Dorothea; Bengtsson, Boel; Heijl, Anders

2013-10-01

To determine the lifetime risk and duration of blindness in patients with manifest open-angle glaucoma (OAG). Retrospective chart review. We studied glaucoma patients who died between January 2006 and June 2010. Most glaucoma patients living in the catchment area (city of Malmö; n = 305 000) are managed at the Department of Ophthalmology at Skåne University Hospital in Malmö. From the patient records we extracted visual field status, visual acuity, and low vision or blindness as defined by the World Health Organization (WHO) criteria and caused by glaucoma at the time of diagnosis and during follow-up. We also noted age at diagnosis and death and when low vision or blindness occurred. Five hundred and ninety-two patients were included. At the time of the last visit 250 patients (42.2%) had at least 1 blind eye because of glaucoma, while 97 patients (16.4%) were bilaterally blind, and 12 patients (0.5%) had low vision. Median time with a glaucoma diagnosis was 12 years (<1-29), median age when developing bilateral blindness was 86 years, and median duration of bilateral blindness was 2 years (<1-13). The cumulative incidences of blindness in at least 1 eye and bilateral blindness from glaucoma were 26.5% and 5.5%, respectively, after 10 years, and 38.1% and 13.5% at 20 years. Approximately 1 out of 6 glaucoma patients was bilaterally blind from glaucoma at the last visit. Median duration of bilateral blindness was 2 years. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Interhemispheric Resource Sharing: Decreasing Benefits with Increasing Processing Efficiency

ERIC Educational Resources Information Center

Maertens, M.; Pollmann, S.

2005-01-01

Visual matches are sometimes faster when stimuli are presented across visual hemifields, compared to within-field matching. Using a cued geometric figure matching task, we investigated the influence of computational complexity vs. processing efficiency on this bilateral distribution advantage (BDA). Computational complexity was manipulated by…

Effects of Visual Speech on Early Auditory Evoked Fields - From the Viewpoint of Individual Variance.

PubMed

Yahata, Izumi; Kawase, Tetsuaki; Kanno, Akitake; Hidaka, Hiroshi; Sakamoto, Shuichi; Nakasato, Nobukazu; Kawashima, Ryuta; Katori, Yukio

2017-01-01

The effects of visual speech (the moving image of the speaker's face uttering speech sound) on early auditory evoked fields (AEFs) were examined using a helmet-shaped magnetoencephalography system in 12 healthy volunteers (9 males, mean age 35.5 years). AEFs (N100m) in response to the monosyllabic sound /be/ were recorded and analyzed under three different visual stimulus conditions, the moving image of the same speaker's face uttering /be/ (congruent visual stimuli) or uttering /ge/ (incongruent visual stimuli), and visual noise (still image processed from speaker's face using a strong Gaussian filter: control condition). On average, latency of N100m was significantly shortened in the bilateral hemispheres for both congruent and incongruent auditory/visual (A/V) stimuli, compared to the control A/V condition. However, the degree of N100m shortening was not significantly different between the congruent and incongruent A/V conditions, despite the significant differences in psychophysical responses between these two A/V conditions. Moreover, analysis of the magnitudes of these visual effects on AEFs in individuals showed that the lip-reading effects on AEFs tended to be well correlated between the two different audio-visual conditions (congruent vs. incongruent visual stimuli) in the bilateral hemispheres but were not significantly correlated between right and left hemisphere. On the other hand, no significant correlation was observed between the magnitudes of visual speech effects and psychophysical responses. These results may indicate that the auditory-visual interaction observed on the N100m is a fundamental process which does not depend on the congruency of the visual information.

The role of prestimulus activity in visual extinction☆

PubMed Central

Urner, Maren; Sarri, Margarita; Grahn, Jessica; Manly, Tom; Rees, Geraint; Friston, Karl

2013-01-01

Patients with visual extinction following right-hemisphere damage sometimes see and sometimes miss stimuli in the left visual field, particularly when stimuli are presented simultaneously to both visual fields. Awareness of left visual field stimuli is associated with increased activity in bilateral parietal and frontal cortex. However, it is unknown why patients see or miss these stimuli. Previous neuroimaging studies in healthy adults show that prestimulus activity biases perceptual decisions, and biases in visual perception can be attributed to fluctuations in prestimulus activity in task relevant brain regions. Here, we used functional MRI to investigate whether prestimulus activity affected perception in the context of visual extinction following stroke. We measured prestimulus activity in stimulus-responsive cortical areas during an extinction paradigm in a patient with unilateral right parietal damage and visual extinction. This allowed us to compare prestimulus activity on physically identical bilateral trials that either did or did not lead to visual extinction. We found significantly increased activity prior to stimulus presentation in two areas that were also activated by visual stimulation: the left calcarine sulcus and right occipital inferior cortex. Using dynamic causal modelling (DCM) we found that both these differences in prestimulus activity and stimulus evoked responses could be explained by enhanced effective connectivity within and between visual areas, prior to stimulus presentation. Thus, we provide evidence for the idea that differences in ongoing neural activity in visually responsive areas prior to stimulus onset affect awareness in visual extinction, and that these differences are mediated by fluctuations in extrinsic and intrinsic connectivity. PMID:23680398

The role of prestimulus activity in visual extinction.

PubMed

Urner, Maren; Sarri, Margarita; Grahn, Jessica; Manly, Tom; Rees, Geraint; Friston, Karl

2013-07-01

Patients with visual extinction following right-hemisphere damage sometimes see and sometimes miss stimuli in the left visual field, particularly when stimuli are presented simultaneously to both visual fields. Awareness of left visual field stimuli is associated with increased activity in bilateral parietal and frontal cortex. However, it is unknown why patients see or miss these stimuli. Previous neuroimaging studies in healthy adults show that prestimulus activity biases perceptual decisions, and biases in visual perception can be attributed to fluctuations in prestimulus activity in task relevant brain regions. Here, we used functional MRI to investigate whether prestimulus activity affected perception in the context of visual extinction following stroke. We measured prestimulus activity in stimulus-responsive cortical areas during an extinction paradigm in a patient with unilateral right parietal damage and visual extinction. This allowed us to compare prestimulus activity on physically identical bilateral trials that either did or did not lead to visual extinction. We found significantly increased activity prior to stimulus presentation in two areas that were also activated by visual stimulation: the left calcarine sulcus and right occipital inferior cortex. Using dynamic causal modelling (DCM) we found that both these differences in prestimulus activity and stimulus evoked responses could be explained by enhanced effective connectivity within and between visual areas, prior to stimulus presentation. Thus, we provide evidence for the idea that differences in ongoing neural activity in visually responsive areas prior to stimulus onset affect awareness in visual extinction, and that these differences are mediated by fluctuations in extrinsic and intrinsic connectivity. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Visual attention in posterior stroke and relations to alexia.

PubMed

Petersen, A; Vangkilde, S; Fabricius, C; Iversen, H K; Delfi, T S; Starrfelt, R

2016-11-01

Impaired visual attention is common following strokes in the territory of the middle cerebral artery, particularly in the right hemisphere, while attentional effects of more posterior lesions are less clear. Commonly, such deficits are investigated in relation to specific syndromes like visual agnosia or pure alexia. The aim of this study was to characterize visual processing speed and apprehension span following posterior cerebral artery (PCA) stroke. In addition, the relationship between these attentional parameters and single word reading is investigated, as previous studies have suggested that reduced visual speed and span may explain pure alexia. Eight patients with unilateral PCA strokes (four left hemisphere, four right hemisphere) were selected on the basis of lesion location, rather than the presence of any visual symptoms. Visual attention was characterized by a whole report paradigm allowing for hemifield-specific measurements of processing speed and apprehension span. All patients showed reductions in visual span contralateral to the lesion site, and four patients showed bilateral reductions in visual span despite unilateral lesions (2L; 2R). Six patients showed selective deficits in visual span, though processing speed was unaffected in the same field (ipsi- or contralesionally). Only patients with right hemifield reductions in visual span were impaired in reading, and this could follow either right or left lateralized stroke and was irrespective of visual field impairments. In conclusion, visual span may be affected bilaterally by unilateral PCA-lesions. Reductions in visual span may also be confined to one hemifield, and may be affected in spite of preserved visual processing speed. Furthermore, reduced span in the right visual field seems to be related to reading impairment in this group, regardless of lesion lateralization. Copyright © 2016 Elsevier Ltd. All rights reserved.

Toxic optic neuropathy following ingestion of homeopathic medication Arnica-30.

PubMed

Venkatramani, Devendra V; Goel, Shubhra; Ratra, Vineet; Gandhi, Rashmin Anilkumar

2013-03-01

We report a case of acute, bilateral and severe vision loss after inadvertent consumption of a large quantity of the homoeopathic medication Arnica-30. Severe vomiting which required hospitalization preceded visual symptoms. In the acute stage, pupillary responses to light were absent and fundus examination was normal. Vision loss followed a fluctuating course, with profound loss noted after 6 weeks along with bilateral optic disc pallor. Neuro-ophthalmic examination and detailed investigations were performed, including magnetic resonance imaging, electroretinography (ERG) and visual evoked potentials (VEP). Ocular coherence tomography (OCT) showed gross thinning of the retinal nerve fiber layer. While a differential diagnosis of posterior ischemic optic neuropathy was kept in mind, these findings supported a diagnosis of bilateral toxic optic neuropathy. Arnica-30 is popularly used to accelerate wound healing, including after oculoplastic surgery. While homeopathic medicines are generally considered safe due to the very low concentrations involved, Arnica-30 may be neurotoxic if consumed internally in large quantities.

Simultaneous perception of a spoken and a signed language: The brain basis of ASL-English code-blends

PubMed Central

Weisberg, Jill; McCullough, Stephen; Emmorey, Karen

2018-01-01

Code-blends (simultaneous words and signs) are a unique characteristic of bimodal bilingual communication. Using fMRI, we investigated code-blend comprehension in hearing native ASL-English bilinguals who made a semantic decision (edible?) about signs, audiovisual words, and semantically equivalent code-blends. English and ASL recruited a similar fronto-temporal network with expected modality differences: stronger activation for English in auditory regions of bilateral superior temporal cortex, and stronger activation for ASL in bilateral occipitotemporal visual regions and left parietal cortex. Code-blend comprehension elicited activity in a combination of these regions, and no cognitive control regions were additionally recruited. Furthermore, code-blends elicited reduced activation relative to ASL presented alone in bilateral prefrontal and visual extrastriate cortices, and relative to English alone in auditory association cortex. Consistent with behavioral facilitation observed during semantic decisions, the findings suggest that redundant semantic content induces more efficient neural processing in language and sensory regions during bimodal language integration. PMID:26177161

Apparent Corneal Ectasia After Bilateral Intrastromal Femtosecond Laser Treatment for Presbyopia.

PubMed

Dukic, Adrijana; Bohac, Maja; Pasalic, Adi; Koncarevic, Mateja; Anticic, Marija; Patel, Sudi

2016-11-01

To report a case of apparent corneal ectasia after intrastromal femtosecond laser treatment for presbyopia (INTRACOR). A healthy 56-year-old male with low hyperopia underwent an unremarkable bilateral INTRACOR procedure in March/April 2011. The patient was discharged after follow-up and returned 5 years later. Before discharge, the monocular logarithm of the minimal angle of resolution uncorrected distance visual acuity (UDVA) values were R, 0.0 and L, 0.10. In both eyes near (UNVA) visual acuities were 0.0. There were signs of slight posterior central corneal steepening without loss of corneal stability. Five years postop, monocular UDVA and UNVA values were 0.4 and 0.0, respectively. Ectasia was observed in both eyes, and the centrally placed 5 concentric rings after the INTRACOR procedure were visible under slit-lamp biomicroscopy. There is no clear reason to explain why the patient developed bilateral corneal steepening. It could be that the patient's corneal stromal fibers gradually weakened over this 5-year period.

Experiments on Auditory-Visual Perception of Sentences by Users of Unilateral, Bimodal, and Bilateral Cochlear Implants

ERIC Educational Resources Information Center

Dorman, Michael F.; Liss, Julie; Wang, Shuai; Berisha, Visar; Ludwig, Cimarron; Natale, Sarah Cook

2016-01-01

Purpose: Five experiments probed auditory-visual (AV) understanding of sentences by users of cochlear implants (CIs). Method: Sentence material was presented in auditory (A), visual (V), and AV test conditions to listeners with normal hearing and CI users. Results: (a) Most CI users report that most of the time, they have access to both A and V…

Purtscher-like retinopathy in acute alcoholic pancreatitis

PubMed Central

Nema, Nitin; Ishrat, Saba; Verma, Abha; Kela, Manoj

2016-01-01

A 23-year-old man with a history of alcoholism presented with vomiting, fever, and sharp epigastric pain radiating to the back and flanks. He was diagnosed as a case of acute alcoholic pancreatitis on the basis of clinical findings and investigations. On the next day of presentation, he developed sudden bilateral visual loss. His best-corrected visual acuity was finger counting at one-foot distance in both eyes. He had diffuse whitening in the circumpapillary area, haloes around the retinal vessels (Purtscher flecken) and intra-retinal hemorrhages on ophthalmoscopic examination. Optical coherence tomography revealed bilateral macular edema. These findings were characteristic of Purtscher-like retinopathy. The patient showed systemic and visual improvement at 8 weeks follow-up after receiving the conventional treatment for acute alcoholic pancreatitis. This case emphasizes the importance of fundus examination by an ophthalmologist in the diagnosis of this rare under-diagnosed entity. PMID:27433040

Purtscher-like retinopathy in acute alcoholic pancreatitis.

PubMed

Nema, Nitin; Ishrat, Saba; Verma, Abha; Kela, Manoj

2016-01-01

A 23-year-old man with a history of alcoholism presented with vomiting, fever, and sharp epigastric pain radiating to the back and flanks. He was diagnosed as a case of acute alcoholic pancreatitis on the basis of clinical findings and investigations. On the next day of presentation, he developed sudden bilateral visual loss. His best-corrected visual acuity was finger counting at one-foot distance in both eyes. He had diffuse whitening in the circumpapillary area, haloes around the retinal vessels (Purtscher flecken) and intra-retinal hemorrhages on ophthalmoscopic examination. Optical coherence tomography revealed bilateral macular edema. These findings were characteristic of Purtscher-like retinopathy. The patient showed systemic and visual improvement at 8 weeks follow-up after receiving the conventional treatment for acute alcoholic pancreatitis. This case emphasizes the importance of fundus examination by an ophthalmologist in the diagnosis of this rare under-diagnosed entity.

Anatomical evidence for the influence of degenerating pathways on regenerating optic fibers following surgical manipulations in the visual system of the goldfish.

PubMed

Lo, R Y; Levine, R L

1981-04-06

We have used [3H]proline radioautography to trace regenerating optic fibers in the goldfish following: (1) the removal of the right tectal lobe and the right eye, and (2) the removal of both tectal lobes. Our results indicate that following the removal of the right tectal lobe and the right eye, both the denervated tectal efferent pathways, and the denervated visual pathways and terminal zones of the enucleated eye were penetrated by the regenerating optic fibers. In addition, following bilateral lobectomy, the denervated tectal efferent pathways were bilaterally penetrated by the regenerating fibers. Since, in both types of operations, these denervated pathways and terminal zones should undergo degeneration, our results support the suggestion that the presence of degenerating axonal debris and proliferating glia may play an important role in guiding regenerating optic fibers in the visual system of the goldfish.

[Impact of timing of surgery on outcome in children with bilateral congenital cataract].

PubMed

Kuhli-Hattenbach, C; Fronius, M; Kohnen, T

2017-03-01

The optimal time for surgical intervention in bilateral congenital cataract is still a matter of controversy. Herein, we evaluated clinical and functional results after bilateral congenital cataract surgery and performed subgroup analysis based on the age at the time of surgery. We retrospectively reviewed the records of 52 eyes of 26 children who underwent surgery for bilateral congenital cataract without intraocular lens implantation within the first 12 months of life; 16 eyes underwent phacoaspiration within the first 10 weeks of life (group A) and 26 eyes had cataract extraction at an age of >10 weeks (group B). We defined the primary outcome measure to be the prevalence of mild, moderate, and severe amblyopia in relationship to age-dependent visual acuity norms after a mean follow-up of 59.7 ± 43.2 months. Secondary outcome measures were interocular difference of visual acuity and the presence of strabismus, nystagmus, posterior capsule opacification, and aphakic glaucoma. The prevalence of amblyopia was not statistically different between the two age groups. Of all children, 62.5 % (A) and 61.1 % (B) developed age-dependent normal visual acuity or mild amblyopia. However, the younger cohort developed significantly less strabismus than the older cohort (P = 0.03). There was a strong relationship between cataract surgery within the first 14 weeks of life and the development of aphakic glaucoma. All children developing secondary cataract formation underwent cataract surgery in the first 20 weeks of life. Our results suggest that long-term prevalence of mild, moderate, and severe amblyopia is similar between the two cohorts of bilateral congenital cataract eyes based on the age ≤ or >10 weeks at the time of surgery. Because there is a strong relationship between postoperative complications and a young age at the time of cataract surgery, close postoperative follow-up is essential. Strabismus is less likely to develop in infants after bilateral cataract surgery within the first 10 weeks of life.

Fulminant bilateral acute retinal necrosis after chickenpox - a case report.

PubMed

Dascalu, Ana Maria; Stana, Daniela; Popa-Cherecheanu, Alina; Popa-Cherecheanu, Matei; Serban, Dragos

2016-01-01

We present the case of a 34-year-old male, admitted for progressive bilateral loss of vision after a recent episode of chickenpox. Ophthalmological exam revealed bilateral acute retinal necrosis. As the patient was following a drug detoxification program, he was tested for HIV, HVB, HVC, and results highly positive. Immediate intravenous therapy with high doses of acyclovir and methylprednisolone was initiated, but the evolution was extremely severe resulting in necrotic retinal detachment. Surgery was performed in right eye, but no improvement of visual acuity was observed. The fulminant evolution of bilateral acute retinal necrosis and the lack of response to maximal intravenous therapy were clinical elements indicating coexistent immunosuppressive disease. Very severe acute retinal necrosis may occur in immunosuppressed patients, leading to blindness.

Orthographic Transparency Modulates the Functional Asymmetry in the Fusiform Cortex: An Artificial Language Training Study

ERIC Educational Resources Information Center

Mei, Leilei; Xue, Gui; Lu, Zhong-Lin; He, Qinghua; Zhang, Mingxia; Xue, Feng; Chen, Chuansheng; Dong, Qi

2013-01-01

The laterality difference in the occipitotemporal region between Chinese (bilaterality) and alphabetic languages (left laterality) has been attributed to their difference in visual appearance. However, these languages also differ in orthographic transparency. To disentangle the effect of orthographic transparency from visual appearance, we trained…

Language Proficiency Modulates the Recruitment of Non-Classical Language Areas in Bilinguals

PubMed Central

Leonard, Matthew K.; Torres, Christina; Travis, Katherine E.; Brown, Timothy T.; Hagler, Donald J.; Dale, Anders M.; Elman, Jeffrey L.; Halgren, Eric

2011-01-01

Bilingualism provides a unique opportunity for understanding the relative roles of proficiency and order of acquisition in determining how the brain represents language. In a previous study, we combined magnetoencephalography (MEG) and magnetic resonance imaging (MRI) to examine the spatiotemporal dynamics of word processing in a group of Spanish-English bilinguals who were more proficient in their native language. We found that from the earliest stages of lexical processing, words in the second language evoke greater activity in bilateral posterior visual regions, while activity to the native language is largely confined to classical left hemisphere fronto-temporal areas. In the present study, we sought to examine whether these effects relate to language proficiency or order of language acquisition by testing Spanish-English bilingual subjects who had become dominant in their second language. Additionally, we wanted to determine whether activity in bilateral visual regions was related to the presentation of written words in our previous study, so we presented subjects with both written and auditory words. We found greater activity for the less proficient native language in bilateral posterior visual regions for both the visual and auditory modalities, which started during the earliest word encoding stages and continued through lexico-semantic processing. In classical left fronto-temporal regions, the two languages evoked similar activity. Therefore, it is the lack of proficiency rather than secondary acquisition order that determines the recruitment of non-classical areas for word processing. PMID:21455315

When apperceptive agnosia is explained by a deficit of primary visual processing.

PubMed

Serino, Andrea; Cecere, Roberto; Dundon, Neil; Bertini, Caterina; Sanchez-Castaneda, Cristina; Làdavas, Elisabetta

2014-03-01

Visual agnosia is a deficit in shape perception, affecting figure, object, face and letter recognition. Agnosia is usually attributed to lesions to high-order modules of the visual system, which combine visual cues to represent the shape of objects. However, most of previously reported agnosia cases presented visual field (VF) defects and poor primary visual processing. The present case-study aims to verify whether form agnosia could be explained by a deficit in basic visual functions, rather that by a deficit in high-order shape recognition. Patient SDV suffered a bilateral lesion of the occipital cortex due to anoxia. When tested, he could navigate, interact with others, and was autonomous in daily life activities. However, he could not recognize objects from drawings and figures, read or recognize familiar faces. He was able to recognize objects by touch and people from their voice. Assessments of visual functions showed blindness at the centre of the VF, up to almost 5°, bilaterally, with better stimulus detection in the periphery. Colour and motion perception was preserved. Psychophysical experiments showed that SDV's visual recognition deficits were not explained by poor spatial acuity or by the crowding effect. Rather a severe deficit in line orientation processing might be a key mechanism explaining SDV's agnosia. Line orientation processing is a basic function of primary visual cortex neurons, necessary for detecting "edges" of visual stimuli to build up a "primal sketch" for object recognition. We propose, therefore, that some forms of visual agnosia may be explained by deficits in basic visual functions due to widespread lesions of the primary visual areas, affecting primary levels of visual processing. Copyright © 2013 Elsevier Ltd. All rights reserved.

Toric vs aspherical control intraocular lenses in patients with cataract and corneal astigmatism: a randomized clinical trial.

PubMed

Visser, Nienke; Beckers, Henny J M; Bauer, Noel J C; Gast, Sacha T J M; Zijlmans, Bart L M; Berenschot, Tos T J M; Webers, Carroll A; Nuijts, Rudy M M A

2014-12-01

Spectacle independence is becoming increasingly important in cataract surgery. Not correcting corneal astigmatism at the time of cataract surgery will fail to achieve spectacle independency in 20% to 30% of patients. To compare bilateral aspherical toric with bilateral aspherical control intraocular lens (IOL) implantation in patients with cataract and corneal astigmatism. A multicenter, hospital-based, randomized clinical trial was conducted. The participants included 86 individuals with bilateral cataract and bilateral corneal astigmatism of at least 1.25 diopters (D) who were randomized to receive either bilateral toric (n = 41) or bilateral control (n = 45) IOL implantation. Bilateral implantation of an aspherical toric IOL or an aspherical control IOL. Spectacle independency for distance vision, uncorrected distance visual acuity, refractive astigmatism, contrast sensitivity, wavefront aberrations, and refractive error-related quality-of-life questionnaire. Preoperatively, mean (SD) corneal astigmatism was 2.02 (0.95) D and 2.00 (0.84) D in the toric and control groups, respectively. Four patients (5%) were lost to follow-up. At 6 months postoperatively, 26 (70%) of the patients in the toric group achieved an uncorrected distance visual acuity of 20/25 or better compared with 14 (31%) in the control group (P < .001; odds ratio, 5.23; 95% CI, 2.03-13.48). Spectacle independency for distance vision was achieved in 31 patients (84%) in the toric group compared with 14 patients (31%) in the control group (P < .001; odds ratio, 11.44; 95% CI, 3.89- 33.63). Mean refractive astigmatism was -0.77 (0.52) D and -1.89 D (1.00) D, respectively. Vector analysis of toric IOLs showed a mean magnitude of error of +0.38 D, indicative of overcorrection. No significant differences were found in contrast sensitivity, higher-order aberrations, or refractive error-related quality of life. In patients with cataract and corneal astigmatism, bilateral toric IOL implantation results in a higher spectacle independency for distance vision compared with bilateral control IOL implantation. No significant differences were identified in contrast sensitivity, higher-order aberrations, or refractive error-related quality of life following both treatments. clinicaltrials.gov Identifier: NCT01075542.

SU5. Investigation of the Visual Steady-State Response in Schizophrenia, Schizoaffective, Psychotic, and Nonpsychotic Bipolar Disorders

PubMed Central

Schneider, Zoe; Parker, David; Kittle, Frances; McDowell, Jennifer; Buckley, Peter; Keedy, Sarah; Gershon, Elliot; Sweeney, John; Keshavan, Matcheri; Pearlson, Godfrey; Tamminga, Carol; Clementz, Brett

2017-01-01

Abstract Background: Electroencephalographic (EEG) studies of the visual steady-state response (ssVEP) probe the oscillatory capacity and synchronization in the primary visual cortex. Previous ssVEP studies have demonstrated early visual processing deficits in schizophrenia (SZ). However, few studies have examined the ssVEP across diagnostic categories and included the full spectrum of psychotic subgroups (schizophrenia: SZ, schizoaffective disorder: SAD, bipolar disorder with psychosis: BDP, and bipolar disorder without psychosis: BD-NP). This is a critical step in order to investigate its potential as a biomarker and to examine specific neural deficits that are unique to each disorder. In this study visual steady-state stimuli in the central, bilateral, left, and right hemisphere were administered to a large sample of well characterized participants diagnosed with SZ, SAD, BDP, or BD-NP. Methods: Four hundred and seven individuals (HC = 153, SZ = 64, SAD = 79, BDP = 65, BD-NP = 46) completed the ssVEP EEG task at the 5 BSNIP sites. A black and white square oscillating at 18.75 Hz was placed in the subject’s central, bilateral, left, and right visual field for 2000 ms. Inter-trial phase coherence (ITC) was calculated for each subject, sensor, and task. The resulting time-frequency values ranged from 4 to 53 Hz and −500 to 2000 ms poststimulus. The 7 peak sensors from the grand average for each task were selected and used to average over the 0–2000 ms ssVEP period for each subject. One-way ANOVA’s and Welch’s t tests were conducted to determine group differences for each task. Results: SAD had significantly reduced ITC in comparison to HC during the bilateral ssVEP task. SZ and SAD both had significantly reduced ITC in comparison to HC and BD-NP during the center visual field trials. There were no significant group differences in either left or right visual field trials for any of the groups. BDP and BD-NP did not differ from HC in any of the conditions. Conclusion: There are 2 main conclusions that can be drawn from this study. (1) Both SZ and SAD had a reduced response to the central stimuli. This is suggestive of a core deficit at the beginning of the visual processing pathway. (2) SAD had a reduction in response the bilateral stimuli. This suggests that SAD has a unique deficit in interhemispheric visual response that is not found in any of the other psychotic or bipolar disorders. Examining differences in the ssVEP between proband groups offers unique insight into how neural synchronization relates to the etiology of SZ and SAD. This provides novel information about core visual processing deficits that could potentially be used as a translational biomarker.

Survey of childhood blindness and visual impairment in Botswana

PubMed Central

Nallasamy, Sudha; Anninger, William V; Quinn, Graham E; Kroener, Brian; Zetola, Nicola M; Nkomazana, Oathokwa

2014-01-01

Background/aims In terms of blind-person years, the worldwide burden of childhood blindness is second only to cataracts. In many developing countries, 30–72% of childhood blindness is avoidable. The authors conducted this study to determine the causes of childhood blindness and visual impairment (VI) in Botswana, a middle-income country with limited access to ophthalmic care. Methods This study was conducted over 4 weeks in eight cities and villages in Botswana. Children were recruited through a radio advertisement and local outreach programmes. Those ≤15 years of age with visual acuity <6/18 in either eye were enrolled. The WHO/Prevention of Blindness Eye Examination Record for Children with Blindness and Low Vision was used to record data. Results The authors enrolled 241 children, 79 with unilateral and 162 with bilateral VI. Of unilateral cases, 89% were avoidable: 23% preventable (83% trauma-related) and 66% treatable (40% refractive error and 31% amblyopia). Of bilateral cases, 63% were avoidable: 5% preventable and 58% treatable (33% refractive error and 31% congenital cataracts). Conclusion Refractive error, which is easily correctable with glasses, is the most common cause of bilateral VI, with cataracts a close second. A nationwide intervention is currently being planned to reduce the burden of avoidable childhood VI in Botswana. PMID:21242581

A bilateral advantage in controlling access to visual short-term memory.

PubMed

Holt, Jessica L; Delvenne, Jean-François

2014-01-01

Recent research on visual short-term memory (VSTM) has revealed the existence of a bilateral field advantage (BFA--i.e., better memory when the items are distributed in the two visual fields than if they are presented in the same hemifield) for spatial location and bar orientation, but not for color (Delvenne, 2005; Umemoto, Drew, Ester, & Awh, 2010). Here, we investigated whether a BFA in VSTM is constrained by attentional selective processes. It has indeed been previously suggested that the BFA may be a general feature of selective attention (Alvarez & Cavanagh, 2005; Delvenne, 2005). Therefore, the present study examined whether VSTM for color benefits from bilateral presentation if attentional selective processes are particularly engaged. Participants completed a color change detection task whereby target stimuli were presented either across both hemifields or within one single hemifield. In order to engage attentional selective processes, some trials contained irrelevant stimuli that needed to be ignored. Targets were selected based on spatial locations (Experiment 1) or on a salient feature (Experiment 2). In both cases, the results revealed a BFA only when irrelevant stimuli were presented among the targets. Overall, the findings strongly suggest that attentional selective processes at encoding can constrain whether a BFA is observed in VSTM.

Bilateral neuroretinitis associated with mumps.

PubMed

Khubchandani, Raju; Rane, Tej; Agarwal, Premlata; Nabi, Fazal; Patel, Phiroze; Shetty, Avinash K

2002-10-01

Involvement of the optic nerve is a rare complication of mumps infection. To report a case of bilateral neuroretinitis complicating a mumps infection and to review 5 previously reported cases. Case report and literature review. Tertiary hospital. A 7-year-old girl had sudden-onset blindness due to bilateral neuroretinitis. Approximately 3 weeks prior to the initial examination, she developed a self-limited febrile illness with parotid swelling and subsequent meningoencephalitis. Mumps was determined to be the underlying cause of the meningoencephalitis and bilateral optic neuritis because of the exposure history in this nonvaccinated child, the typical clinical signs and symptoms, and the positive serologic test results. Recovery of visual function was gradual but nearly complete. Physicians should be aware that optic nerve involvement may be a manifestation of mumps infection. The delayed onset of optic neuritis, the bilateral involvement, and the near complete recovery suggest an immune-mediated pathogenesis.

Audio-visual speech perception in prelingually deafened Japanese children following sequential bilateral cochlear implantation.

PubMed

Yamamoto, Ryosuke; Naito, Yasushi; Tona, Risa; Moroto, Saburo; Tamaya, Rinko; Fujiwara, Keizo; Shinohara, Shogo; Takebayashi, Shinji; Kikuchi, Masahiro; Michida, Tetsuhiko

2017-11-01

An effect of audio-visual (AV) integration is observed when the auditory and visual stimuli are incongruent (the McGurk effect). In general, AV integration is helpful especially in subjects wearing hearing aids or cochlear implants (CIs). However, the influence of AV integration on spoken word recognition in individuals with bilateral CIs (Bi-CIs) has not been fully investigated so far. In this study, we investigated AV integration in children with Bi-CIs. The study sample included thirty one prelingually deafened children who underwent sequential bilateral cochlear implantation. We assessed their responses to congruent and incongruent AV stimuli with three CI-listening modes: only the 1st CI, only the 2nd CI, and Bi-CIs. The responses were assessed in the whole group as well as in two sub-groups: a proficient group (syllable intelligibility ≥80% with the 1st CI) and a non-proficient group (syllable intelligibility < 80% with the 1st CI). We found evidence of the McGurk effect in each of the three CI-listening modes. AV integration responses were observed in a subset of incongruent AV stimuli, and the patterns observed with the 1st CI and with Bi-CIs were similar. In the proficient group, the responses with the 2nd CI were not significantly different from those with the 1st CI whereas in the non-proficient group the responses with the 2nd CI were driven by visual stimuli more than those with the 1st CI. Our results suggested that prelingually deafened Japanese children who underwent sequential bilateral cochlear implantation exhibit AV integration abilities, both in monaural listening as well as in binaural listening. We also observed a higher influence of visual stimuli on speech perception with the 2nd CI in the non-proficient group, suggesting that Bi-CIs listeners with poorer speech recognition rely on visual information more compared to the proficient subjects to compensate for poorer auditory input. Nevertheless, poorer quality auditory input with the 2nd CI did not interfere with AV integration with binaural listening (with Bi-CIs). Overall, the findings of this study might be used to inform future research to identify the best strategies for speech training using AV integration effectively in prelingually deafened children. Copyright © 2017 Elsevier B.V. All rights reserved.

Structural Alteration of the Dorsal Visual Network in DLB Patients with Visual Hallucinations: A Cortical Thickness MRI Study

PubMed Central

Delli Pizzi, Stefano; Franciotti, Raffaella; Tartaro, Armando; Caulo, Massimo; Thomas, Astrid; Onofrj, Marco; Bonanni, Laura

2014-01-01

Visual hallucinations (VH) represent one of the core features in discriminating dementia with Lewy bodies (DLB) from Alzheimer’s Disease (AD). Previous studies reported that in DLB patients functional alterations of the parieto-occipital regions were correlated with the presence of VH. The aim of our study was to assess whether morphological changes in specific cortical regions of DLB could be related to the presence and severity of VH. We performed a cortical thickness analysis on magnetic resonance imaging data in a cohort including 18 DLB patients, 15 AD patients and 14 healthy control subjects. Relatively to DLB group, correlation analysis between the cortical thickness and the Neuropsychiatric Inventory (NPI) hallucination item scores was also performed. Cortical thickness was reduced bilaterally in DLB compared to controls in the pericalcarine and lingual gyri, cuneus, precuneus, superior parietal gyrus. Cortical thinning was found bilaterally in AD compared to controls in temporal cortex including the superior and middle temporal gyrus, part of inferior temporal cortex, temporal pole and insula. Inferior parietal and supramarginal gyri were also affected bilaterally in AD as compared to controls. The comparison between DLB and AD evidenced cortical thinning in DLB group in the right posterior regions including superior parietal gyrus, precuneus, cuneus, pericalcarine and lingual gyri. Furthermore, the correlation analysis between cortical thickness and NPI hallucination item scores showed that the structural alteration in the dorsal visual regions including superior parietal gyrus and precuneus closely correlated with the occurrence and severity of VH. We suggest that structural changes in key regions of the dorsal visual network may play a crucial role in the physiopathology of VH in DLB patients. PMID:24466177

Visual outcomes of bilateral congenital and developmental cataracts in young children in south India and causes of poor outcome.

PubMed

Khanna, Rohit C; Foster, Allen; Krishnaiah, Sannapaneni; Mehta, Manohar K; Gogate, Parikshit M

2013-02-01

Bilateral pediatric cataracts are important cause of visual impairment in children. To study the outcome of bilateral pediatric cataract surgery in young children. Retrospective case series in a tertiary center. Records of pediatric cataracts operated between January 2001 and December 2003, with a minimum follow-up of 3 months, were reviewed retrospectively. Independent sample t-test, Fisher's exact test, and logistic regression using SPSS (Statistical Package for Social Science, Chicago, USA) version 12. 215/257 (83.7%) patients had a minimum follow-up of 3 months. The mean age of presentation to the hospital was 53 months (range: 0-168 months). Congenital cataract was present in 107 patients (58.2%) and developmental cataract in 77 patients (41.8%). The mean age at surgery was 55.2 months (range: 1-168 months). Out of 430 eyes, 269 (62.6%) had an intraocular lens implanted. The mean duration of follow-up was 13.1 months (range: 3-38 months). Pre-operatively, 102 patients (47.3%) had visual acuity <6/60, in the better eye, compared to 37 patients (17.2%) post-operatively ( P < 0.001). Eighty-five patients (39.5%) had visual acuity >6/18. The most common early post-operative complication was fibrinous uveitis in 57 eyes (13.3%) and the most common delayed post-operative complication was posterior capsular opacification in 118 eyes (27.4%). The most important prognostic factor for poor outcome was congenital cataract (odds ratio [OR]: 26.3; 95% confidence interval [CI], 4.4-158.5) and total cataract (OR: 4.8; 95% CI, 1.3-17). Nearly half of the eyes had visual acuity >6/18. The outcome was poorer in congenital cataracts, especially those operated after >1 year of age.

Preserved Haptic Shape Processing after Bilateral LOC Lesions.

PubMed

Snow, Jacqueline C; Goodale, Melvyn A; Culham, Jody C

2015-10-07

The visual and haptic perceptual systems are understood to share a common neural representation of object shape. A region thought to be critical for recognizing visual and haptic shape information is the lateral occipital complex (LOC). We investigated whether LOC is essential for haptic shape recognition in humans by studying behavioral responses and brain activation for haptically explored objects in a patient (M.C.) with bilateral lesions of the occipitotemporal cortex, including LOC. Despite severe deficits in recognizing objects using vision, M.C. was able to accurately recognize objects via touch. M.C.'s psychophysical response profile to haptically explored shapes was also indistinguishable from controls. Using fMRI, M.C. showed no object-selective visual or haptic responses in LOC, but her pattern of haptic activation in other brain regions was remarkably similar to healthy controls. Although LOC is routinely active during visual and haptic shape recognition tasks, it is not essential for haptic recognition of object shape. The lateral occipital complex (LOC) is a brain region regarded to be critical for recognizing object shape, both in vision and in touch. However, causal evidence linking LOC with haptic shape processing is lacking. We studied recognition performance, psychophysical sensitivity, and brain response to touched objects, in a patient (M.C.) with extensive lesions involving LOC bilaterally. Despite being severely impaired in visual shape recognition, M.C. was able to identify objects via touch and she showed normal sensitivity to a haptic shape illusion. M.C.'s brain response to touched objects in areas of undamaged cortex was also very similar to that observed in neurologically healthy controls. These results demonstrate that LOC is not necessary for recognizing objects via touch. Copyright © 2015 the authors 0270-6474/15/3513745-16$15.00/0.

fMRI characterisation of widespread brain networks relevant for behavioural variability in fine hand motor control with and without visual feedback.

PubMed

Mayhew, Stephen D; Porcaro, Camillo; Tecchio, Franca; Bagshaw, Andrew P

2017-03-01

A bilateral visuo-parietal-motor network is responsible for fine control of hand movements. However, the sub-regions which are devoted to maintenance of contraction stability and how these processes fluctuate with trial-quality of task execution and in the presence/absence of visual feedback remains unclear. We addressed this by integrating behavioural and fMRI measurements during right-hand isometric compression of a compliant rubber bulb, at 10% and 30% of maximum voluntary contraction, both with and without visual feedback of the applied force. We quantified single-trial behavioural performance during 1) the whole task period and 2) stable contraction maintenance, and regressed these metrics against the fMRI data to identify the brain activity most relevant to trial-by-trial fluctuations in performance during specific task phases. fMRI-behaviour correlations in a bilateral network of visual, premotor, primary motor, parietal and inferior frontal cortical regions emerged during performance of the entire feedback task, but only in premotor, parietal cortex and thalamus during the stable contraction period. The trials with the best task performance showed increased bilaterality and amplitude of fMRI responses. With feedback, stronger BOLD-behaviour coupling was found during 10% compared to 30% contractions. Only a small subset of regions in this network were weakly correlated with behaviour without feedback, despite wider network activated during this task than in the presence of feedback. These findings reflect a more focused network strongly coupled to behavioural fluctuations when providing visual feedback, whereas without it the task recruited widespread brain activity almost uncoupled from behavioural performance. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Immediately sequential bilateral cataract surgery: advantages and disadvantages.

PubMed

Singh, Ranjodh; Dohlman, Thomas H; Sun, Grace

2017-01-01

The number of cataract surgeries performed globally will continue to rise to meet the needs of an aging population. This increased demand will require healthcare systems and providers to find new surgical efficiencies while maintaining excellent surgical outcomes. Immediately sequential bilateral cataract surgery (ISBCS) has been proposed as a solution and is increasingly being performed worldwide. The purpose of this review is to discuss the advantages and disadvantages of ISBCS. When appropriate patient selection occurs and guidelines are followed, ISBCS is comparable with delayed sequential bilateral cataract surgery in long-term patient satisfaction, visual acuity and complication rates. In addition, the risk of bilateral postoperative endophthalmitis and concerns of poorer refractive outcomes have not been supported by the literature. ISBCS is cost-effective for the patient, healthcare payors and society, but current reimbursement models in many countries create significant financial barriers for facilities and surgeons. As demand for cataract surgery rises worldwide, ISBCS will become increasingly important as an alternative to delayed sequential bilateral cataract surgery. Advantages include potentially decreased wait times for surgery, patient convenience and cost savings for healthcare payors. Although they are comparable in visual acuity and complication rates, hurdles that prevent wide adoption include liability concerns as ISBCS is not an established standard of care, economic constraints for facilities and surgeons and inability to fine-tune intraocular lens selection in the second eye. Given these considerations, an open discussion regarding the advantages and disadvantages of ISBCS is important for appropriate patient selection.

A visual stethoscope to detect the position of the tracheal tube.

PubMed

Kato, Hiromi; Suzuki, Akira; Nakajima, Yoshiki; Makino, Hiroshi; Sanjo, Yoshimitsu; Nakai, Takayoshi; Shiraishi, Yoshito; Katoh, Takasumi; Sato, Shigehito

2009-12-01

Advancing a tracheal tube into the bronchus produces unilateral breath sounds. We created a Visual Stethoscope that allows real-time fast Fourier transformation of the sound signal and 3-dimensional (frequency-amplitude-time) color rendering of the results on a personal computer with simultaneous processing of 2 individual sound signals. The aim of this study was to evaluate whether the Visual Stethoscope can detect bronchial intubation in comparison with auscultation. After induction of general anesthesia, the trachea was intubated with a tracheal tube. The distance from the incisors to the carina was measured using a fiberoptic bronchoscope. While the anesthesiologist advanced the tracheal tube from the trachea to the bronchus, another anesthesiologist auscultated breath sounds to detect changes of the breath sounds and/or disappearance of bilateral breath sounds for every 1 cm that the tracheal tube was advanced. Two precordial stethoscopes placed at the left and right sides of the chest were used to record breath sounds simultaneously. Subsequently, at a later date, we randomly entered the recorded breath sounds into the Visual Stethoscope. The same anesthesiologist observed the visualized breath sounds on the personal computer screen processed by the Visual Stethoscope to examine changes of breath sounds and/or disappearance of bilateral breath sound. We compared the decision made based on auscultation with that made based on the results of the visualized breath sounds using the Visual Stethoscope. Thirty patients were enrolled in the study. When irregular breath sounds were auscultated, the tip of the tracheal tube was located at 0.6 +/- 1.2 cm on the bronchial side of the carina. Using the Visual Stethoscope, when there were any changes of the shape of the visualized breath sound, the tube was located at 0.4 +/- 0.8 cm on the tracheal side of the carina (P < 0.01). When unilateral breath sounds were auscultated, the tube was located at 2.6 +/- 1.2 cm on the bronchial side of the carina. The tube was also located at 2.3 +/- 1.0 cm on the bronchial side of the carina when a unilateral shape of visualized breath sounds was obtained using the Visual Stethoscope (not significant). During advancement of the tracheal tube, alterations of the shape of the visualized breath sounds using the Visual Stethoscope appeared before the changes of the breath sounds were detected by auscultation. Bilateral breath sounds disappeared when the tip of the tracheal tube was advanced beyond the carina in both groups.

Structural brain alterations in primary open angle glaucoma: a 3T MRI study

PubMed Central

Wang, Jieqiong; Li, Ting; Sabel, Bernhard A.; Chen, Zhiqiang; Wen, Hongwei; Li, Jianhong; Xie, Xiaobin; Yang, Diya; Chen, Weiwei; Wang, Ningli; Xian, Junfang; He, Huiguang

2016-01-01

Glaucoma is not only an eye disease but is also associated with degeneration of brain structures. We now investigated the pattern of visual and non-visual brain structural changes in 25 primary open angle glaucoma (POAG) patients and 25 age-gender-matched normal controls using T1-weighted imaging. MRI images were subjected to volume-based analysis (VBA) and surface-based analysis (SBA) in the whole brain as well as ROI-based analysis of the lateral geniculate nucleus (LGN), visual cortex (V1/2), amygdala and hippocampus. While VBA showed no significant differences in the gray matter volumes of patients, SBA revealed significantly reduced cortical thickness in the right frontal pole and ROI-based analysis volume shrinkage in LGN bilaterally, right V1 and left amygdala. Structural abnormalities were correlated with clinical parameters in a subset of the patients revealing that the left LGN volume was negatively correlated with bilateral cup-to-disk ratio (CDR), the right LGN volume was positively correlated with the mean deviation of the right visual hemifield, and the right V1 cortical thickness was negatively correlated with the right CDR in glaucoma. These results demonstrate that POAG affects both vision-related structures and non-visual cortical regions. Moreover, alterations of the brain visual structures reflect the clinical severity of glaucoma. PMID:26743811

Simultaneous bilateral cataract surgery: economic analysis; Helsinki Simultaneous Bilateral Cataract Surgery Study Report 2.

PubMed

Leivo, Tiina; Sarikkola, Anna-Ulrika; Uusitalo, Risto J; Hellstedt, Timo; Ess, Sirje-Linda; Kivelä, Tero

2011-06-01

To present an economic-analysis comparison of simultaneous and sequential bilateral cataract surgery. Helsinki University Eye Hospital, Helsinki, Finland. Economic analysis. Effects were estimated from data in a study in which patients were randomized to have bilateral cataract surgery on the same day (study group) or sequentially (control group). The main clinical outcomes were corrected distance visual acuity, refraction, complications, Visual Function Index-7 (VF-7) scores, and patient-rated satisfaction with vision. Health-care costs of surgeries and preoperative and postoperative visits were estimated, including the cost of staff, equipment, material, floor space, overhead, and complications. The data were obtained from staff measurements, questionnaires, internal hospital records, and accountancy. Non-health-care costs of travel, home care, and time were estimated based on questionnaires from a random subset of patients. The main economic outcome measures were cost per VF-7 score unit change and cost per patient in simultaneous versus sequential surgery. The study comprised 520 patients (241 patients included non-health-care and time cost analyses). Surgical outcomes and patient satisfaction were similar in both groups. Simultaneous cataract surgery saved 449 Euros (€) per patient in health-care costs and €739 when travel and paid home-care costs were included. The savings added up to €849 per patient when the cost of lost working time was included. Compared with sequential bilateral cataract surgery, simultaneous bilateral cataract surgery provided comparable clinical outcomes with substantial savings in health-care and non-health-care-related costs. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Hearing thresholds in patients with drug-resistant tuberculosis: baseline audiogram configurations and associations.

PubMed

Sogebi, Olusola Ayodele; Fadeyi, Muse Olatunbosun; Adefuye, Bolanle Olufunlola; Soyinka, Festus Olukayode

2017-01-01

To use baseline audiogram parameters in order to ascertain whether drug-resistant tuberculosis (DR-TB) has effects on hearing, as well as to describe the configurations of the audiograms and to determine whether there are parameters that can be associated with those configurations. This was a prospective study involving patients diagnosed with DR-TB at a tuberculosis treatment center in the state of Ogun, in Nigeria. The patients included in the study were submitted to pure tone audiometry at baseline (within two weeks after treatment initiation). For comparative analyses, data regarding demographic and clinical characteristics were collected from the medical records of the patients. The final sample comprised 132 patients. The mean age of the patients was 34.5 ± 12.6 years (range, 8-82 years), and the male:female ratio was 2:1. Of the 132 patients, 103 (78.0%) resided in neighboring states, 125 (94.7%) had previously experienced antituberculosis treatment failure, and 18 (13.6%) were retroviral-positive. Normal audiograms were found in 12 patients (9.1%), whereas sensorineural hearing loss was identified in 104 (78.8%), the two most common configurations being ascending, in 54 (40.9%), and sloping, in 26 (19.7%). Pure-tone averages at low frequencies (0.25-1.0 kHz) and high frequencies (2.0-8.0 kHz) were 33.0 dB and 40.0 dB, respectively. Regarding the degree of hearing loss in the better ear, 36 patients (27.3%) were classified as having normal hearing and 67 (50.8%) were classified as having mild hearing loss (26-40 dB), whereas 29 (21.9%) showed moderate or severe hearing loss. Among the variables studied (age, gender, retroviral status, previous treatment outcome, and weight at admission), only male gender was associated with audiometric configurations. In this sample of patients with DR-TB, most presented with bilateral, mild, suboptimal sensorineural hearing loss, and ascending/sloping audiometric configurations were associated with male gender. Utilizar parâmetros do audiograma basal para verificar se a tuberculose resistente (TB-R) tem efeitos na audição, descrever as configurações dos audiogramas e determinar se há parâmetros que possam ser associados a essas configurações. Estudo prospectivo com pacientes diagnosticados com TB-R em um centro de tratamento de tuberculose no estado de Ogun, Nigéria. Os pacientes incluídos no estudo foram submetidos à audiometria de tons puros em até duas semanas após o início do tratamento (audiometria basal). Características demográficas e clínicas foram coletadas dos prontuários médicos dos pacientes para análises comparativas. A amostra final envolveu 132 pacientes. A média de idade dos pacientes foi de 34,5 ± 12,6 anos (variação, 8-82 anos), e a razão homem:mulher foi de 2:1. A maioria dos pacientes (n = 103; 78,0%) residia nos estados vizinhos e tinha história de falha de tratamento antituberculose (n = 125; 94.7%); 18 (13.6%) apresentavam status retroviral positivo. Doze pacientes (9,1%) apresentaram audiogramas normais, e 104 (78,8%) apresentaram perda auditiva neurossensorial, sendo as configurações mais comuns do tipo ascendente, em 54 (40,9%), e descendente, em 26 (19,7%). As médias de tons puros em frequências baixas (0,25-1,0 kHz) e altas (2,0-8,0 kHz) foram de 33,0 dB e 40,0 dB, respectivamente. Quanto ao grau de perda auditiva no melhor ouvido, 36 pacientes (27,3%) apresentaram audição normal, e 67 (50,8%) apresentaram perda auditiva leve (26-40 dB), enquanto 29 (21,9%) mostraram perda auditiva moderada ou grave. Entre as variáveis estudadas (idade, gênero, status retroviral, desfecho de tratamento anterior e peso na admissão), somente o gênero masculino foi associado às configurações audiométricas. Nesta amostra de pacientes com TB-R, a maioria apresentou perda auditiva neurossensorial leve e subótima bilateralmente, com configurações audiométricas ascendentes/descendentes associadas ao gênero masculino.

Bilateral nongranulomatous uveitis with infective endocarditis.

PubMed

Ha, Sang Won; Shin, Jae Pil; Kim, Si Yeol; Park, Dong Ho

2013-02-01

A 32-year-old male who had infective endocarditis complained of photophobia and blurred vision in both eyes. Biomicroscopic examination and fundus examination revealed anterior chamber reaction, vitritis, optic disc swelling, and Roth spots. He was diagnosed with bilateral nongranulomatous uveitis and treated with topical steroid eye drops and posterior sub-Tenon injection of triamcinolone. His visual symptoms were resolved within 1 week, and inflammation resolved within 4 weeks after treatment.

Bilateral Nongranulomatous Uveitis with Infective Endocarditis

PubMed Central

Ha, Sang Won; Shin, Jae Pil; Kim, Si Yeol

2013-01-01

A 32-year-old male who had infective endocarditis complained of photophobia and blurred vision in both eyes. Biomicroscopic examination and fundus examination revealed anterior chamber reaction, vitritis, optic disc swelling, and Roth spots. He was diagnosed with bilateral nongranulomatous uveitis and treated with topical steroid eye drops and posterior sub-Tenon injection of triamcinolone. His visual symptoms were resolved within 1 week, and inflammation resolved within 4 weeks after treatment. PMID:23372383

Bilateral Ocular Decompression Retinopathy after Ahmed Valve Implantation for Uveitic Glaucoma.

PubMed

Flores-Preciado, Javier; Ancona-Lezama, David Arturo; Valdés-Lara, Carlos Andrés; Díez-Cattini, Gian Franco; Coloma-González, Itziar

2016-01-01

We report the case of a 29-year-old man who underwent Ahmed valve implantation in both eyes as treatment for uveitic glaucoma, subsequently presenting with bilateral ocular decompression retinopathy in the postoperative period. Ocular decompression retinopathy is a rare complication of filtering surgery in patients with glaucoma; however, the course is benign in most cases, with spontaneous resolution of bleedings and improvement of visual acuity.

Bilateral ring-shaped intrastromal opacities after corneal cross-linking for keratoconus.

PubMed

Camesasca, Fabrizio I; Vinciguerra, Paolo; Seiler, Theo

2011-12-01

To report a case of bilateral, ring-shaped, intrastromal corneal opacities after corneal cross-linking (CXL) for progressive keratoconus. A 21-year-old man with bilateral, progressive keratoconus underwent CXL with riboflavin 0.1% and ultraviolet A (UVA) light in the right eye and, 6 months later, in the left eye. One day after CXL, the right eye showed a sharply demarcated white ring in the corneal periphery. The ring involved the superficial stroma at 2 mm from the limbus, extended from 1 to 11 o'clock, and was 1.5-mm wide. Corneal topography showed marked central flattening. Six months after treatment, a residual, faint, ring-shaped opacity remained, with a decrease in corneal ectasia. Cross-linking was then performed in the left eye. Different ultraviolet devices were used in the two eyes. On postoperative day 1, the left eye also showed a white ring of stromal opacity. Scheimpflug imaging showed corneal stromal contraction in the zone of whitening. At final examination, >1 year after surgery, corrected visual acuity was 0.00 logMAR with cylinder of 2.00 diopters in both eyes. The bilateral intrastromal corneal changes were innocuous in the long-term, with preservation of good visual acuity and successful stabilization of progressive keratoconus.

Effects of Visual Speech on Early Auditory Evoked Fields - From the Viewpoint of Individual Variance

PubMed Central

Yahata, Izumi; Kanno, Akitake; Hidaka, Hiroshi; Sakamoto, Shuichi; Nakasato, Nobukazu; Kawashima, Ryuta; Katori, Yukio

2017-01-01

The effects of visual speech (the moving image of the speaker’s face uttering speech sound) on early auditory evoked fields (AEFs) were examined using a helmet-shaped magnetoencephalography system in 12 healthy volunteers (9 males, mean age 35.5 years). AEFs (N100m) in response to the monosyllabic sound /be/ were recorded and analyzed under three different visual stimulus conditions, the moving image of the same speaker’s face uttering /be/ (congruent visual stimuli) or uttering /ge/ (incongruent visual stimuli), and visual noise (still image processed from speaker’s face using a strong Gaussian filter: control condition). On average, latency of N100m was significantly shortened in the bilateral hemispheres for both congruent and incongruent auditory/visual (A/V) stimuli, compared to the control A/V condition. However, the degree of N100m shortening was not significantly different between the congruent and incongruent A/V conditions, despite the significant differences in psychophysical responses between these two A/V conditions. Moreover, analysis of the magnitudes of these visual effects on AEFs in individuals showed that the lip-reading effects on AEFs tended to be well correlated between the two different audio-visual conditions (congruent vs. incongruent visual stimuli) in the bilateral hemispheres but were not significantly correlated between right and left hemisphere. On the other hand, no significant correlation was observed between the magnitudes of visual speech effects and psychophysical responses. These results may indicate that the auditory-visual interaction observed on the N100m is a fundamental process which does not depend on the congruency of the visual information. PMID:28141836

A 14-year-old girl who regained normal vision after bilateral visual impairment following hot water injury to the eyes.

PubMed

Monsudi, Kehinde F; Ayanniyi, Abdulkabir A

2011-04-01

A 14-year-old girl presented with bilateral visual impairment following hot water injury to the eyes. The patient was admitted for a week and managed with guttae tropicamide 0.5% 8 h, diclofenac sodium 0.1% 4 h, and fluoroquinolone 0.3% 6 h and ointment chloramphenicol 8 h. Also, the patient was managed with capsule doxycycline 100 mg 12 h for 10 days, tablet cataflam 50 mg 12 h for 7 days and intramuscular tetanus toxoid 0.5 mg stat and dermacine cream for facial scald. The visual acuities improved from 3/60 (right eye) and 6/24 (left eye) to 6/6 in both eyes. There were resolutions of facial/eye pain, tearing, photophobia, lid edema, blepharospasm, and conjunctival hyperemia. There was complete healing of facial wounds and corneal ulcers. She was discharged from hospital on the 7th day of admission. Prompt presentation, degree of scald sustained, and appropriate medical intervention enhanced visual recovery and wound healing in the patient.

Impaired integration of object knowledge and visual input in a case of ventral simultanagnosia with bilateral damage to area V4.

PubMed

Leek, E Charles; d'Avossa, Giovanni; Tainturier, Marie-Josèphe; Roberts, Daniel J; Yuen, Sung Lai; Hu, Mo; Rafal, Robert

2012-01-01

This study examines how brain damage can affect the cognitive processes that support the integration of sensory input and prior knowledge during shape perception. It is based on the first detailed study of acquired ventral simultanagnosia, which was found in a patient (M.T.) with posterior occipitotemporal lesions encompassing V4 bilaterally. Despite showing normal object recognition for single items in both accuracy and response times (RTs), and intact low-level vision assessed across an extensive battery of tests, M.T. was impaired in object identification with overlapping figures displays. Task performance was modulated by familiarity: Unlike controls, M.T. was faster with overlapping displays of abstract shapes than with overlapping displays of common objects. His performance with overlapping common object displays was also influenced by both the semantic relatedness and visual similarity of the display items. These findings challenge claims that visual perception is driven solely by feedforward mechanisms and show how brain damage can selectively impair high-level perceptual processes supporting the integration of stored knowledge and visual sensory input.

Ocular findings in MELAS syndrome – a case report.

PubMed

Modrzejewska, Monika; Chrzanowska, Martyna; Modrzejewska, Anna; Romanowska, Hanna; Ostrowska, Iwona; Giżewska, Maria

We present a case of a child with MELAS syndrome (mitochondrial encephalo-myopathy with lactic acidosis and stroke-like episodes), discussing clinical manifestation, ocular findings and diagnostic challenges. Predominant ocular symptom was a transient complete visual loss, while the predominant ocular sign was a visual field defect. The diagnosia was based on clinical manifestation, laboratory tests, brain scans and genetic testing which confirmed the pathognomonic mutation in the MTTL1 gene encoding the mitochondrial tRNA for leucine 3243> G. Ocular examination demonstrated decreased visual acuity (with bilateral best corrected visual acuity of .1). Periodical, transient visual loss and visual field defects were clinically predominant. Specialist investigations were carried out, which demonstrated homonymous hemianopia (kinetic perimetry), bilateral partial optic nerve atrophy (RetCam). Funduscopy and electrophysiology mfERG study did not confirm features of retinitis pigmentosa. The brain scans revealed numerous small cortical ischemic lesions within the frontal, parietal and temporal lobes, post-stroke focal areas within the occipital lobes and diffuse calcifications of the basal ganglia. During several years of follow-up, visual field defects showed progressive concentric narrowing. The patient received a long-term treatment with arginine, coenzyme Q and vitamin D, both oral and intravenous, but no beneficial effect for the improvement of ophthalmic condition was observed. As it is the case in severe MELAS syndrome, the course of disease was fatal and the patientdied at the age of 14.

Like father, like son: periventricular nodular heterotopia and nonverbal learning disorder.

PubMed

McCann, Marcia V; Pongonis, Stephen J; Golomb, Meredith R; Edwards-Brown, Mary; Christensen, Celanie K; Sokol, Deborah K

2008-08-01

Periventricular nodular heterotopia is a common malformation of cortical development in which the migration of developing neurons destined for the cerebral cortex is abbreviated. Bilateral periventricular nodular heterotopia is most commonly an X-linked disorder that involves mutations in the filamin A (FLNA) gene, but an autosomal recessive form and sporadic forms have been identified. To our knowledge, autosomal dominant transmission of isolated periventricular nodular heterotopia has not been reported. Periventricular nodular heterotopia has a heterogeneous phenotype, associated commonly with seizure disorder, and more recently with reading deficits and visual-spatial deficits in some patients. We present a father and son with bilateral periventricular nodular heterotopia and similar visual-spatial learning deficits, consistent with nonverbal learning disability.

[Reduced vision in Wernicke's syndrome with symptoms of nystagmus].

PubMed

Lindholt, Michael E

2006-04-03

A 42-year-old man presented in the Department of Ophthalmology of Holstebro Central Hospital with a history of alcohol abuse, vomiting and weight loss. The initial symptoms of beriberi were stiffness of the legs and a picture of Wernicke's syndrome. He had bilateral loss of horizontal eccentric gaze holding and upbeat nystagmus, and visual acuity was reduced to counting fingers. Visual acuity was tested in the down-gaze position and increased to 0.3 because of reduced nystagmus. The patient's oculomotor function improved dramatically after treatment with thiamine. Wernicke's encephalopathy and beriberi are discussed, highlighting that nystagmus may be the single ocular symptom. It should be considered in the differential diagnosis of bilateral ophthalmoplegia even in the absence of altered mental status.

Optic nerve lesion following neuroborreliosis: a case report.

PubMed

Burkhard, C; Gleichmann, M; Wilhelm, H

2001-01-01

Neuroborreliosis may cause various neuro-ophthalmological complications. We describe a case with a bilateral optic neuropathy. A 58-year-old female developed facial paresis six weeks after an insect bite. One week later she developed bilateral optic disc swelling with haemorrhages and nerve fibre bundle defects in the lower visual field of the left eye. In CSF and serum, raised IgM and IgG titres to Borrelia burgdorferi were found. Systemic antibiotic treatment led to improvement of the vision and facial paresis, but not all visual field defects resolved, probably due to ischemic lesions of the optic disc. In optic nerve lesions due to neuroborreliosis it is difficult to distinguish between inflammatory and ischemic lesions. This patient demonstrated features of an ischemic optic nerve lesion.

More than blindsight: Case report of a child with extraordinary visual capacity following perinatal bilateral occipital lobe injury.

PubMed

Mundinano, Inaki-Carril; Chen, Juan; de Souza, Mitchell; Sarossy, Marc G; Joanisse, Marc F; Goodale, Melvyn A; Bourne, James A

2017-11-13

Injury to the primary visual cortex (V1, striate cortex) and the geniculostriate pathway in adults results in cortical blindness, abolishing conscious visual perception. Early studies by Larry Weiskrantz and colleagues demonstrated that some patients with an occipital-lobe injury exhibited a degree of unconscious vision and visually-guided behaviour within the blind field. A more recent focus has been the observed phenomenon whereby early-life injury to V1 often results in the preservation of visual perception in both monkeys and humans. These findings initiated a concerted effort on multiple fronts, including nonhuman primate studies, to uncover the neural substrate/s of the spared conscious vision. In both adult and early-life cases of V1 injury, evidence suggests the involvement of the Middle Temporal area (MT) of the extrastriate visual cortex, which is an integral component area of the dorsal stream and is also associated with visually-guided behaviors. Because of the limited number of early-life V1 injury cases for humans, the outstanding question in the field is what secondary visual pathways are responsible for this extraordinary capacity? Here we report for the first time a case of a child (B.I.) who suffered a bilateral occipital-lobe injury in the first two weeks postnatally due to medium-chain acyl-Co-A dehydrogenase deficiency. At 6 years of age, B.I. underwent a battery of neurophysiological tests, as well as structural and diffusion MRI and ophthalmic examination at 7 years. Despite the extensive bilateral occipital cortical damage, B.I. has extensive conscious visual abilities, is not blind, and can use vision to navigate his environment. Furthermore, unlike blindsight patients, he can readily and consciously identify happy and neutral faces and colors, tasks associated with ventral stream processing. These findings suggest significant re-routing of visual information. To identify the putative visual pathway/s responsible for this ability, MRI tractography of secondary visual pathways connecting MT with the lateral geniculate nucleus (LGN) and the inferior pulvinar (PI) were analysed. Results revealed an increased PI-MT pathway in the left hemisphere, suggesting that this pulvinar relay could be the neural pathway affording the preserved visual capacity following an early-life lesion of V1. These findings corroborate anatomical evidence from monkeys showing an enhanced PI-MT pathway following an early-life lesion of V1, compared to adults. Copyright © 2017 Elsevier Ltd. All rights reserved.

Postural Control in Bilateral Vestibular Failure: Its Relation to Visual, Proprioceptive, Vestibular, and Cognitive Input.

PubMed

Sprenger, Andreas; Wojak, Jann F; Jandl, Nico M; Helmchen, Christoph

2017-01-01

Patients with bilateral vestibular failure (BVF) suffer from postural and gait unsteadiness with an increased risk of falls. The aim of this study was to elucidate the differential role of otolith, semicircular canal (SSC), visual, proprioceptive, and cognitive influences on the postural stability of BVF patients. Center-of-pressure displacements were recorded by posturography under six conditions: target visibility; tonic head positions in the pitch plane; horizontal head shaking; sensory deprivation; dual task; and tandem stance. Between-group analysis revealed larger postural sway in BVF patients on eye closure; but with the eyes open, BVF did not differ from healthy controls (HCs). Head tilts and horizontal head shaking increased sway but did not differ between groups. In the dual task condition, BVF patients maintained posture indistinguishable from controls. On foam and tandem stance, postural sway was larger in BVF, even with the eyes open. The best predictor for the severity of bilateral vestibulopathy was standing on foam with eyes closed. Postural control of our BVF was indistinguishable from HCs once visual and proprioceptive feedback is provided. This distinguishes them from patients with vestibulo-cerebellar disorders or functional dizziness. It confirms previous reports and explains that postural unsteadiness of BVF patients can be missed easily if not examined by conditions of visual and/or proprioceptive deprivation. In fact, the best predictor for vestibular hypofunction (VOR gain) was examining patients standing on foam with the eyes closed. Postural sway in that condition increased with the severity of vestibular impairment but not with disease duration. In the absence of visual control, impaired otolith input destabilizes BVF with head retroflexion. Stimulating deficient SSC does not distinguish patients from controls possibly reflecting a shift of intersensory weighing toward proprioceptive-guided postural control. Accordingly, proprioceptive deprivation heavily destabilizes BVF, even when visual control is provided.

Postural Control in Bilateral Vestibular Failure: Its Relation to Visual, Proprioceptive, Vestibular, and Cognitive Input

PubMed Central

Sprenger, Andreas; Wojak, Jann F.; Jandl, Nico M.; Helmchen, Christoph

2017-01-01

Patients with bilateral vestibular failure (BVF) suffer from postural and gait unsteadiness with an increased risk of falls. The aim of this study was to elucidate the differential role of otolith, semicircular canal (SSC), visual, proprioceptive, and cognitive influences on the postural stability of BVF patients. Center-of-pressure displacements were recorded by posturography under six conditions: target visibility; tonic head positions in the pitch plane; horizontal head shaking; sensory deprivation; dual task; and tandem stance. Between-group analysis revealed larger postural sway in BVF patients on eye closure; but with the eyes open, BVF did not differ from healthy controls (HCs). Head tilts and horizontal head shaking increased sway but did not differ between groups. In the dual task condition, BVF patients maintained posture indistinguishable from controls. On foam and tandem stance, postural sway was larger in BVF, even with the eyes open. The best predictor for the severity of bilateral vestibulopathy was standing on foam with eyes closed. Postural control of our BVF was indistinguishable from HCs once visual and proprioceptive feedback is provided. This distinguishes them from patients with vestibulo-cerebellar disorders or functional dizziness. It confirms previous reports and explains that postural unsteadiness of BVF patients can be missed easily if not examined by conditions of visual and/or proprioceptive deprivation. In fact, the best predictor for vestibular hypofunction (VOR gain) was examining patients standing on foam with the eyes closed. Postural sway in that condition increased with the severity of vestibular impairment but not with disease duration. In the absence of visual control, impaired otolith input destabilizes BVF with head retroflexion. Stimulating deficient SSC does not distinguish patients from controls possibly reflecting a shift of intersensory weighing toward proprioceptive-guided postural control. Accordingly, proprioceptive deprivation heavily destabilizes BVF, even when visual control is provided. PMID:28919878

Amblyopia prevalence and risk factors in Australian preschool children.

PubMed

Pai, Amy Shih-I; Rose, Kathryn A; Leone, Jody F; Sharbini, Sharimawati; Burlutsky, George; Varma, Rohit; Wong, Tien Yin; Mitchell, Paul

2012-01-01

To determine the prevalence of and factors associated with amblyopia in a sample of Australian preschool children. Population-based, cross-sectional study. The Sydney Paediatric Eye Disease Study examined 2461 (73.8% participation) children aged between 6 and 72 months from 2007 to 2009. Visual acuity (VA) was assessed in children aged ≥ 30 months using the Electronic Visual Acuity system, and a subset using the logarithm of the minimum angle of resolution chart. Amblyopia was categorized into unilateral and bilateral subtypes: Unilateral amblyopia was defined as a 2-line difference in reduced VA between the 2 eyes, in addition to strabismus, anisometropia, and/or visual axis obstruction; bilateral amblyopia was defined as bilateral reduced VA with either bilateral visual axis obstruction or significant bilateral ametropia. Information on ethnicity, birth parameters, and measures of socioeconomic status were collected in questionnaires completed by parents. Amblyopia. We included 1422 children aged 30 to 72 months, of whom 27 (1.9%) were found to have amblyopia or suspected amblyopia. Mean spherical equivalent for the amblyopic eyes was +3.57 diopters, with a mean VA of 20/50. Only 3 of the 27 amblyopic children had previous diagnoses or treatments for amblyopia. In regression analysis controlling for age, gender, and ethnicity, amblyopia was significantly associated with hyperopia (odds ratio [OR], 15.3; 95% confidence interval [CI], 6.5-36.4), astigmatism (OR, 5.7; 95% CI, 2.5-12.7), anisometropia (OR, 27.8; 95% CI, 11.2-69.3), and strabismus (OR, 13.1; 95% CI, 4.3-40.4). There were no significant associations of amblyopia with low birthweight (<2500 g), preterm birth (<37 weeks), maternal smoking, age, gender, ethnicity, or measures of socioeconomic status (all P>0.05). Amblyopia was found in 1.9% of this Australian preschool sample, which is comparable with prevalence rates reported by other recent studies in preschool children. Refractive errors, particularly significant hyperopia and astigmatism, in addition to anisometropia and strabismus, were the major amblyogenic factors. There was a low amblyopia detection rate in this preschool population, which suggests that different strategies are required to improve current vision screening strategies in preschoolers. The authors have no proprietary or commercial interest in any of the materials discussed in this article. Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Occipitoparietal alpha-band responses to the graded allocation of top-down spatial attention.

PubMed

Dombrowe, Isabel; Hilgetag, Claus C

2014-09-15

The voluntary, top-down allocation of visual spatial attention has been linked to changes in the alpha-band of the electroencephalogram (EEG) signal measured over occipital and parietal lobes. In the present study, we investigated how occipitoparietal alpha-band activity changes when people allocate their attentional resources in a graded fashion across the visual field. We asked participants to either completely shift their attention into one hemifield, to balance their attention equally across the entire visual field, or to attribute more attention to one-half of the visual field than to the other. As expected, we found that alpha-band amplitudes decreased stronger contralaterally than ipsilaterally to the attended side when attention was shifted completely. Alpha-band amplitudes decreased bilaterally when attention was balanced equally across the visual field. However, when participants allocated more attentional resources to one-half of the visual field, this was not reflected in the alpha-band amplitudes, which just decreased bilaterally. We found that the performance of the participants was more strongly reflected in the coherence between frontal and occipitoparietal brain regions. We conclude that low alpha-band amplitudes seem to be necessary for stimulus detection. Furthermore, complete shifts of attention are directly reflected in the lateralization of alpha-band amplitudes. In the present study, a gradual allocation of visual attention across the visual field was only indirectly reflected in the alpha-band activity over occipital and parietal cortexes. Copyright © 2014 the American Physiological Society.

Orienting attention in visual space by nociceptive stimuli: investigation with a temporal order judgment task based on the adaptive PSI method.

PubMed

Filbrich, Lieve; Alamia, Andrea; Burns, Soline; Legrain, Valéry

2017-07-01

Despite their high relevance for defending the integrity of the body, crossmodal links between nociception, the neural system specifically coding potentially painful information, and vision are still poorly studied, especially the effects of nociception on visual perception. This study investigated if, and in which time window, a nociceptive stimulus can attract attention to its location on the body, independently of voluntary control, to facilitate the processing of visual stimuli occurring in the same side of space as the limb on which the visual stimulus was applied. In a temporal order judgment task based on an adaptive procedure, participants judged which of two visual stimuli, one presented next to either hand in either side of space, had been perceived first. Each pair of visual stimuli was preceded (by 200, 400, or 600 ms) by a nociceptive stimulus applied either unilaterally on one single hand, or bilaterally, on both hands simultaneously. Results show that, as compared to the bilateral condition, participants' judgments were biased to the advantage of the visual stimuli that occurred in the same side of space as the hand on which a unilateral, nociceptive stimulus was applied. This effect was present in a time window ranging from 200 to 600 ms, but importantly, biases increased with decreasing time interval. These results suggest that nociceptive stimuli can affect the perceptual processing of spatially congruent visual inputs.

A new goldfish model to evaluate pharmacokinetic and pharmacodynamic effects of drugs used for motion sickness in different gravity loads

NASA Astrophysics Data System (ADS)

Lathers, Claire M.; Mukai, Chiaki; Smith, Cedric M.; Schraeder, Paul L.

2001-08-01

This paper proposes a new goldfish model to predict pharmacodynamic/pharmacokinetic effects of drugs used to treat motion sickness administered in differing gravity loads. The assumption of these experiments is that the vestibular system is dominant in producing motion sickness and that the visual system is secondary or of small import in the production of motion sickness. Studies will evaluate the parameter of gravity and the contribution of vision to the role of the neurovestibular system in the initiation of motion sickness with and without pharmacologic agents. Promethazine will be studied first. A comparison of data obtained in different groups of goldfish will be done (normal vs. acutely and chronically bilaterally blinded vs. sham operated). Some fish will be bilaterally blinded 10 months prior to initiation of the experiment (designated the chronically bilaterally blinded group of goldfish) to evaluate the neuroplasticity of the nervous system and the associated return of neurovestibular function. Data will be obtained under differing gravity loads with and without a pharmacological agent for motion sickness. Experiments will differentiate pharmacological effects on vision vs. neurovestibular input to motion sickness. Comparison of data obtained in the normal fish and in acutely and chronically bilaterally blinded fish with those obtained in fish with intact and denervated otoliths will differentiate if the visual or neurovestibular system is dominant in response to altered gravity and/or drugs. Experiments will contribute to validation of the goldfish as a model for humans since plasticity of the central nervous system allows astronauts to adapt to the altered visual stimulus conditions of 0-g. Space motion sickness may occur until such an adaptation is achieved.

Visual and Refractive Outcomes following Bilateral Implantation of Extended Range of Vision Intraocular Lens with Micromonovision

PubMed Central

Ganesh, Sri; Relekar, Kirti J.

2018-01-01

Purpose To evaluate the outcomes following bilateral ERV intraocular lens implantation with micromonovision. Methods 25 subjects underwent bilateral Tecnis Symfony IOL implantation with micromonovision. The dominant eye was targeted for emmetropia and the nondominant eye for myopia of −0.75 D. Uncorrected and corrected distance (UDVA, CDVA), intermediate (UIVA, CIVA), and near visual acuity (UNVA, DCNVA); reading performance; defocus curve; and contrast sensitivity were studied. Follow-ups were conducted at 1 week and 1 and 6 months postoperatively. Results At 6 months postoperatively, the mean binocular UDVA, CDVA, UNVA, and DCNVA were −0.036 ± 0.09, −0.108 ± 0.07, 0.152 ± 0.11, and 0.216 ± 0.10 logMAR, respectively. Binocular UIVA and DCIVA were 0.048 ± 0.09 and 0.104 ± 0.08 logMAR, respectively, at 60 cm and −0.044 ± 0.09 and 0.012 ± 0.09 logMAR, respectively, at 80 cm. All patients had ≥0.2 logMAR UDVA and UNVA. Reading acuity and reading speeds showed improvement over time. Between defocus range of −2.50 and +1.00 D, the visual acuity remained ≥0.2 logMAR. Contrast sensitivity scores were within the normal range. 4 patients used reading glasses for very fine print. Conclusion Bilateral ERV IOL implantation leads to excellent outcomes for far and intermediate vision, satisfactory outcomes for near vision, and good tolerance to micromonovision at the end of the 6 months. This trial is registered with CTRI/2015/10/006246. PMID:29545954

[Usher syndrome: about a case].

PubMed

Daoudi, Chama; Boutimzine, Noureddine; Haouzi, Samia El; Lezrek, Omar; Tachfouti, Samira; Lezrek, Mounir; Laghmari, Mina; Daoudi, Rajae

2017-01-01

Usher syndrome is a genetic disease resulting in double sensory deprivation (auditory and visual) called deafblindness. We report the case of a 50-year old patient, born to consanguineous parents, presenting with congenital deafness associated with normal vestibular function and pigmentary retinopathy responsible for decreased bilateral visual acuity occurred at the age of 16 years. This association composes Usher syndrome type 2, a rare autosomal recessive disorder. Cataract surgery allowed visual acuity improvement in this patient.

MAINTENANCE OF GOOD VISUAL ACUITY IN BEST DISEASE ASSOCIATED WITH CHRONIC BILATERAL SEROUS MACULAR DETACHMENT.

PubMed

Gattoussi, Sarra; Boon, Camiel J F; Freund, K Bailey

2017-08-10

We describe the long-term follow-up of a patient with multifocal Best disease with chronic bilateral serous macular detachment and unusual peripheral findings associated with a novel mutation in the BEST1 gene. Case report. A 59-year-old white woman was referred for an evaluation of her macular findings in 1992. There was a family history of Best disease in the patient's mother and a male sibling. Her medical history was unremarkable. Best-corrected visual acuity was 20/20 in her right eye and 20/25 in her left eye. The anterior segment examination was normal in both eyes. Funduscopic examination showed multifocal hyperautofluorescent vitelliform deposits with areas of subretinal fibrosis in both eyes. An electrooculogram showed Arden ratios of 1.32 in the right eye and 1.97 in the left eye. Ultra-widefield color and fundus autofluorescence imaging showed degenerative retinal changes in areas throughout the entire fundus in both eyes. Optical coherence tomography, including annual eye-tracked scans from 2005 to 2016, showed persistent bilateral serous macular detachments. Despite chronic foveal detachment, visual acuity was 20/25 in her right eye and 20/40 in her left eye, 24 years after initial presentation. Genetic testing showed a novel c.238T>A (p.Phe80Ile) missense mutation in the BEST1 gene. Some patients with Best disease associated with chronic serous macular detachment can maintain good visual acuity over an extended follow-up. To our knowledge, this is the first report of Best disease associated with this mutation in the BEST1 gene.

Bilateral Ocular Decompression Retinopathy after Ahmed Valve Implantation for Uveitic Glaucoma

PubMed Central

Flores-Preciado, Javier; Ancona-Lezama, David Arturo; Valdés-Lara, Carlos Andrés; Díez-Cattini, Gian Franco; Coloma-González, Itziar

2016-01-01

Case Report We report the case of a 29-year-old man who underwent Ahmed valve implantation in both eyes as treatment for uveitic glaucoma, subsequently presenting with bilateral ocular decompression retinopathy in the postoperative period. Discussion Ocular decompression retinopathy is a rare complication of filtering surgery in patients with glaucoma; however, the course is benign in most cases, with spontaneous resolution of bleedings and improvement of visual acuity. PMID:27920718

Fluorouracil as a treatment for corneal papilloma in a Malayan tapir.

PubMed

Karpinski, Lorraine G; Miller, Christine L

2002-09-01

A 26-year-old, wild caught, male Malayan tapir at the Miami Metrozoo with bilateral corneal papillomas was serially immobilized and given subconjunctival injections of fluorouracil. Over the course of 17 weeks five bilateral injections of 25 mg fluorouracil were given. This treatment caused regression of the corneal lesions as evidenced by decreased lesion diameter, decreased corneal vascularity, increased corneal clarity, and improved visual function. No adverse drug effects were observed.

Bilateral orbital emphysema and pneumocephalus as a result of accidental compressed air exposure.

PubMed

Yuksel, Murvet; Yuksel, K Zafer; Ozdemir, Gokhan; Ugur, Tuncay

2007-01-01

Orbital emphysema is a rare condition in the absence of trauma or sinus disease. A 22-year-old man suffering from left orbital trauma due to sudden exposure to compressed air tube was admitted with severe pain in the left eye, swelling, and mild periorbital ecchymosis. Physical examination revealed a large conjunctival laceration in the left orbit. Multislice computed tomographic scanning of the head and orbits showed extensive radiolucencies consistent with the air in both orbits, more prominent in the left. There was also subcutaneous air in the left periorbital soft tissue extending through fronto-temporal and zygomatic areas. Air was also demonstrated adjacent to the left optic canal and within the subarachnoid space intracranially. There was no evidence of any orbital, paranasal sinus, or cranial fracture. Visual acuity was minimally decreased bilaterally. The conjunctiva was sutured under local anesthesia. After 3 weeks of follow-up, the patient completely recovered without visual loss. Bilateral orbital emphysema with pneumocephalus can occur from a high-pressure compressed air injury after unilateral conjunctival trauma without any evidence of fracture.

The Effects of Bilateral Presentations on Lateralized Lexical Decision

ERIC Educational Resources Information Center

Fernandino, Leonardo; Iacoboni, Marco; Zaidel, Eran

2007-01-01

We investigated how lateralized lexical decision is affected by the presence of distractors in the visual hemifield contralateral to the target. The study had three goals: first, to determine how the presence of a distractor (either a word or a pseudoword) affects visual field differences in the processing of the target; second, to identify the…

Anton-Babinski syndrome in an old patient: a case report and literature review.

PubMed

Chen, Jiann-Jy; Chang, Hsin-Feng; Hsu, Yung-Chu; Chen, Dem-Lion

2015-03-01

Anton-Babinski syndrome is a rare disease featuring bilateral cortical blindness and anosognosia with visual confabulation, but without dementia or any memory impairment. It has a unique neuropsychiatric presentation and should be highly suspected in those with odd visual loss and imaging evidence of occipital lobe injury. In the case discussed herein, a 90-year-old man presented with bilateral blindness, obvious anosognosia, and vivid visual confabulation, which he had had for 3 days. Brain computed tomography demonstrated recent hypodense infarctions at the bilateral occipital lobes. Thus, the patient was diagnosed with Anton-Babinski syndrome. Because of his age and the thrombolytic therapy during the golden 3 hours after ischemic stroke, the patient received aspirin therapy rather than tissue plasminogen activator or warfarin. He gradually realized he was blind during the following week, but died of pneumonia 1 month later. In the literature, it is difficult to establish awareness of blindness in patients with Anton-Babinski syndrome, but optimistically, in one report, a patient was aware of blindness within 2 weeks, without vision improvement. Our case illustrates that elderly patients with Anton-Babinski syndrome can partially recover and that 1 week is the shortest time for the establishment of awareness of blindness for sufferers without vision improvement. © 2014 The Authors. Psychogeriatrics © 2014 Japanese Psychogeriatric Society.

An fMRI Study of the Neural Systems Involved in Visually Cued Auditory Top-Down Spatial and Temporal Attention

PubMed Central

Li, Chunlin; Chen, Kewei; Han, Hongbin; Chui, Dehua; Wu, Jinglong

2012-01-01

Top-down attention to spatial and temporal cues has been thoroughly studied in the visual domain. However, because the neural systems that are important for auditory top-down temporal attention (i.e., attention based on time interval cues) remain undefined, the differences in brain activity between directed attention to auditory spatial location (compared with time intervals) are unclear. Using fMRI (magnetic resonance imaging), we measured the activations caused by cue-target paradigms by inducing the visual cueing of attention to an auditory target within a spatial or temporal domain. Imaging results showed that the dorsal frontoparietal network (dFPN), which consists of the bilateral intraparietal sulcus and the frontal eye field, responded to spatial orienting of attention, but activity was absent in the bilateral frontal eye field (FEF) during temporal orienting of attention. Furthermore, the fMRI results indicated that activity in the right ventrolateral prefrontal cortex (VLPFC) was significantly stronger during spatial orienting of attention than during temporal orienting of attention, while the DLPFC showed no significant differences between the two processes. We conclude that the bilateral dFPN and the right VLPFC contribute to auditory spatial orienting of attention. Furthermore, specific activations related to temporal cognition were confirmed within the superior occipital gyrus, tegmentum, motor area, thalamus and putamen. PMID:23166800

MACULAR HOLE FORMATION FOLLOWED BY SPONTANEOUS CLOSURE AFTER PNEUMATIC RETINOPEXY IN A PATIENT WITH DIABETIC MACULAR EDEMA.

PubMed

Cohen, Michael N; Baumal, Caroline R

2018-05-10

To report early formation and spontaneous closure of a full-thickness macular hole that developed after successful pneumatic retinopexy in a patient who had been undergoing treatment for diabetic macular edema. Case report of a 68-year-old man with bilateral nonproliferative diabetic retinopathy who was currently undergoing anti-vascular endothelial growth factor treatment for bilateral diabetic macular edema. On presentation, visual acuity was 20/200 in the left eye, and examination revealed a bullous, macula-off retinal detachment with a single horseshoe tear at 12 o'clock in the left eye. Pneumatic retinopexy was performed followed by laser augmentation 3 days later. Three weeks postoperatively, he returned with visual acuity of 20/50 and a full-thickness macular hole in the left eye. Although he elected for initial observation, he returned 2 weeks later with visual acuity of 20/50 in both eyes and a retinal detachment with a single break at 10 o'clock in the right eye. The macular hole in the left eye had spontaneously resolved. Pneumatic retinopexy was performed to the right eye. Over 1 year after bilateral pneumatic retinopexy, his retina remains without recurrence of a macular hole in the left eye. In the early postoperative period after pneumatic retinopexy to repair a retinal detachment, a macular hole can form and spontaneously close.

Visual impairment and amblyopia in Malaysian pre-school children - The SEGPAEDS study.

PubMed

Chew, F L M; Thavaratnam, L K; Shukor, I N C; Ramasamy, S; Rahmat, J; Reidpath, D D; Allotey, P; Alagaratnam, J

2018-02-01

Little is known regarding the extent of visual impairment amongst pre-school children in Malaysia. To determine the prevalence of visual impairment and amblyopia in Malaysian preschool children. A cross-sectional, population-based study was conducted on children aged four to six years from 51 participating kindergartens in the district of Segamat, Johor, Malaysia from 20 March 2016 to 6 April 2016. All subjects had initial eye screening consisting of LogMar visual acuity, orthoptics examination and Spot vision screener assessment. Subjects who failed the initial eye screening were invited for a formal eye assessment consisting of cycloplegic refraction and a comprehensive ocular examination. Definitions of visual impairment and amblyopia were based on the Multi-Ethnic Pediatric Eye Disease Study criteria. A total of 1287 children were recruited. Mean subject age was 5.03 (SD:0.77) and males represented 52.3% of subjects. Subjects by ethnicity were Malay (54.8%), Chinese (27.7%), Indian (15.6%) and Orang Asli (1.9%). Formal eye assessment was required for 221 subjects and 88.8% required ophthalmic intervention. Refractive error, representing 95.4% of diagnosed ocular disorders, comprised of astigmatism (84%), myopia (9%) and hypermetropia (6.9%). With-the-rule astigmatism was present in 93.4% of the subjects with astigmatism. Visual impairment was present in 12.5% of our subjects, with 61% having bilateral visual impairment. Of the subjects with visual impairment, 59.1% had moderate visual impairment. The prevalence of amblyopia was 7.53%, and 66% of the amblyopic subjects had bilateral amblyopia. Our study highlights an urgent need for initiation of preschool vision screening in Malaysia.

Holistic neural coding of Chinese character forms in bilateral ventral visual system.

PubMed

Mo, Ce; Yu, Mengxia; Seger, Carol; Mo, Lei

2015-02-01

How are Chinese characters recognized and represented in the brain of skilled readers? Functional MRI fast adaptation technique was used to address this question. We found that neural adaptation effects were limited to identical characters in bilateral ventral visual system while no activation reduction was observed for partially overlapping characters regardless of the spatial location of the shared sub-character components, suggesting highly selective neuronal tuning to whole characters. The consistent neural profile across the entire ventral visual cortex indicates that Chinese characters are represented as mutually distinctive wholes rather than combinations of sub-character components, which presents a salient contrast to the left-lateralized, simple-to-complex neural representations of alphabetic words. Our findings thus revealed the cultural modulation effect on both local neuronal activity patterns and functional anatomical regions associated with written symbol recognition. Moreover, the cross-language discrepancy in written symbol recognition mechanism might stem from the language-specific early-stage learning experience. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Bilateral Central Retinal Vein Occlusion as Presenting Feature of Chronic Myeloid Leukemia

PubMed Central

Narang, Subina; Gupta, Panchmi; Sharma, Anuj; Sood, Sunandan; Palta, Anshu; Goyal, Shilpa

2016-01-01

Central retinal vein occlusion (CRVO) is a common pathology of the retinal vasculature. Patients with CRVO usually present with a drop in visual acuity. The condition bears no specific therapy; treatment is aimed at the management of potentially blinding complications, of which there are many. With majority of cases being unilateral, bilateral CRVO is usually associated with an underlying systemic illness such as a hyperviscosity syndrome. Here, we present a case of a patient, who presented with a bilateral drop in vision diagnosed as bilateral CRVO on ophthalmic evaluation. Systemic workup revealed the presence of an underlying undiagnosed chronic myeloid leukemia. An initial presentation to the ophthalmologist is a rare occurrence in leukemic patients. This case report highlights the role of the ophthalmologist in diagnosing a potentially life-threatening hematological illness. PMID:27555710

Language networks in anophthalmia: maintained hierarchy of processing in 'visual' cortex.

PubMed

Watkins, Kate E; Cowey, Alan; Alexander, Iona; Filippini, Nicola; Kennedy, James M; Smith, Stephen M; Ragge, Nicola; Bridge, Holly

2012-05-01

Imaging studies in blind subjects have consistently shown that sensory and cognitive tasks evoke activity in the occipital cortex, which is normally visual. The precise areas involved and degree of activation are dependent upon the cause and age of onset of blindness. Here, we investigated the cortical language network at rest and during an auditory covert naming task in five bilaterally anophthalmic subjects, who have never received visual input. When listening to auditory definitions and covertly retrieving words, these subjects activated lateral occipital cortex bilaterally in addition to the language areas activated in sighted controls. This activity was significantly greater than that present in a control condition of listening to reversed speech. The lateral occipital cortex was also recruited into a left-lateralized resting-state network that usually comprises anterior and posterior language areas. Levels of activation to the auditory naming and reversed speech conditions did not differ in the calcarine (striate) cortex. This primary 'visual' cortex was not recruited to the left-lateralized resting-state network and showed high interhemispheric correlation of activity at rest, as is typically seen in unimodal cortical areas. In contrast, the interhemispheric correlation of resting activity in extrastriate areas was reduced in anophthalmia to the level of cortical areas that are heteromodal, such as the inferior frontal gyrus. Previous imaging studies in the congenitally blind show that primary visual cortex is activated in higher-order tasks, such as language and memory to a greater extent than during more basic sensory processing, resulting in a reversal of the normal hierarchy of functional organization across 'visual' areas. Our data do not support such a pattern of organization in anophthalmia. Instead, the patterns of activity during task and the functional connectivity at rest are consistent with the known hierarchy of processing in these areas normally seen for vision. The differences in cortical organization between bilateral anophthalmia and other forms of congenital blindness are considered to be due to the total absence of stimulation in 'visual' cortex by light or retinal activity in the former condition, and suggests development of subcortical auditory input to the geniculo-striate pathway.

Visual object agnosia is associated with a breakdown of object-selective responses in the lateral occipital cortex.

PubMed

Ptak, Radek; Lazeyras, François; Di Pietro, Marie; Schnider, Armin; Simon, Stéphane R

2014-07-01

Patients with visual object agnosia fail to recognize the identity of visually presented objects despite preserved semantic knowledge. Object agnosia may result from damage to visual cortex lying close to or overlapping with the lateral occipital complex (LOC), a brain region that exhibits selectivity to the shape of visually presented objects. Despite this anatomical overlap the relationship between shape processing in the LOC and shape representations in object agnosia is unknown. We studied a patient with object agnosia following isolated damage to the left occipito-temporal cortex overlapping with the LOC. The patient showed intact processing of object structure, yet often made identification errors that were mainly based on the global visual similarity between objects. Using functional Magnetic Resonance Imaging (fMRI) we found that the damaged as well as the contralateral, structurally intact right LOC failed to show any object-selective fMRI activity, though the latter retained selectivity for faces. Thus, unilateral damage to the left LOC led to a bilateral breakdown of neural responses to a specific stimulus class (objects and artefacts) while preserving the response to a different stimulus class (faces). These findings indicate that representations of structure necessary for the identification of objects crucially rely on bilateral, distributed coding of shape features. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Role of Anterior Nuclei of the Thalamus: A Subcortical Gate in Memory Processing: An Intracerebral Recording Study.

PubMed

Štillová, Klára; Jurák, Pavel; Chládek, Jan; Chrastina, Jan; Halámek, Josef; Bočková, Martina; Goldemundová, Sabina; Říha, Ivo; Rektor, Ivan

2015-01-01

To study the involvement of the anterior nuclei of the thalamus (ANT) as compared to the involvement of the hippocampus in the processes of encoding and recognition during visual and verbal memory tasks. We studied intracerebral recordings in patients with pharmacoresistent epilepsy who underwent deep brain stimulation (DBS) of the ANT with depth electrodes implanted bilaterally in the ANT and compared the results with epilepsy surgery candidates with depth electrodes implanted bilaterally in the hippocampus. We recorded the event-related potentials (ERPs) elicited by the visual and verbal memory encoding and recognition tasks. P300-like potentials were recorded in the hippocampus by visual and verbal memory encoding and recognition tasks and in the ANT by the visual encoding and visual and verbal recognition tasks. No significant ERPs were recorded during the verbal encoding task in the ANT. In the visual and verbal recognition tasks, the P300-like potentials in the ANT preceded the P300-like potentials in the hippocampus. The ANT is a structure in the memory pathway that processes memory information before the hippocampus. We suggest that the ANT has a specific role in memory processes, especially memory recognition, and that memory disturbance should be considered in patients with ANT-DBS and in patients with ANT lesions. ANT is well positioned to serve as a subcortical gate for memory processing in cortical structures.

Familial history of reading difficulty is associated with diffused bilateral brain activation during reading and greater association with visual attention abilities.

PubMed

Horowitz-Kraus, Tzipi

2017-10-01

Reading difficulty (RD; or dyslexia) is a heritable condition characterized by slow, inaccurate reading accompanied by executive dysfunction, specifically with respect to visual attention. The current study was designed to examine the effect of familial history of RD on the relationship between reading and visual attention abilities in children with RD using a functional MRI reading task. Seventy-one children with RD participated in the study. Based on parental reports of the existence of RD in one or both of each child's parents, children with RD were divided into two groups: (1) those with a familial history of RD and (2) those without a familial history of RD. Reading and visual attention measures were collected from all participants. Functional MRI data during word reading was acquired in 30 participants of the entire cohort. Children with or without a familial history of RD demonstrated below-average reading and visual attention scores, with greater interaction between these measures in the group with a familial history of RD. Greater bilateral and diffused activation during word reading also were found in this group. We suggest that a familial history of RD is related to greater association between lower reading abilities and visual attention abilities. Parental history of RD therefore may be an important preschool screener (before reading age) to prompt early intervention focused on executive functions and reading-related skills.

Persistent visual impairment in multiple sclerosis: prevalence, mechanisms and resulting disability.

PubMed

Jasse, Laurence; Vukusic, Sandra; Durand-Dubief, Françoise; Vartin, Cristina; Piras, Carolina; Bernard, Martine; Pélisson, Denis; Confavreux, Christian; Vighetto, Alain; Tilikete, Caroline

2013-10-01

The objective of this article is to evaluate in multiple sclerosis (MS) patients the prevalence of persistent complaints of visual disturbances and the mechanisms and resulting functional disability of persistent visual complaints (PVCs). Firstly, the prevalence of PVCs was calculated in 303 MS patients. MS-related data of patients with or without PVCs were compared. Secondly, 70 patients with PVCs performed an extensive neuro-ophthalmologic assessment and a vision-related quality of life questionnaire, the National Eye Institute Visual Functionary Questionnaire (NEI-VFQ-25). PVCs were reported in 105 MS patients (34.6%). Patients with PVCs had more frequently primary progressive MS (30.5% vs 13.6%) and more neuro-ophthalmologic relapses (1.97 vs 1.36) than patients without PVCs. In the mechanisms/disability study, an afferent visual and an ocular-motor pathways dysfunction were respectively diagnosed in 41 and 59 patients, mostly related to bilateral optic neuropathy and bilateral internuclear ophthalmoplegia. The NEI-VFQ 25 score was poor and significantly correlated with the number of impaired neuro-ophthalmologic tests. Our study emphasizes the high prevalence of PVC in MS patients. Regarding the nature of neuro-ophthalmologic deficit, our results suggest that persistent optic neuropathy, as part of the progressive evolution of the disease, is not rare. We also demonstrate that isolated ocular motor dysfunctions induce visual disability in daily life.

Effects of Age-Related Macular Degeneration on Postural Sway

PubMed Central

Chatard, Hortense; Tepenier, Laure; Jankowski, Olivier; Aussems, Antoine; Allieta, Alain; Beydoun, Talal; Salah, Sawsen; Bucci, Maria P.

2017-01-01

Purpose: To compare the impact of unilateral vs. bilateral age-related macular degeneration (AMD) on postural sway, and the influence of different visual conditions. The hypothesis of our study was that the impact of AMD will be different between unilateral and bilateral AMD subjects compared to age-matched healthy elderly. Methods: Postural stability was measured with a platform (TechnoConcept®) in 10 elderly unilateral AMD subjects (mean age: 71.1 ± 4.6 years), 10 elderly bilateral AMD subjects (mean age: 70.8 ± 6.1 years), and 10 healthy age-matched control subjects (mean age: 69.8 ± 6.3 years). Four visual conditions were tested: both eyes viewing condition (BEV), dominant eye viewing (DEV), non-dominant eye viewing (NDEV), and eyes closed (EC). We analyzed the surface area, the length, the mean speed, the anteroposterior (AP), and mediolateral (ML) displacement of the center of pressure (CoP). Results: Bilateral AMD subjects had a surface area (p < 0.05) and AP displacement of the CoP (p < 0.01) higher than healthy elderly. Unilateral AMD subjects had more AP displacement of the CoP (p < 0.05) than healthy elderly. Conclusions: We suggest that ADM subjects could have poor postural adaptive mechanisms leading to increase their postural instability. Further studies will aim to improve knowledge on such issue and to develop reeducation techniques in these patients. PMID:28408876

Evaluation of a Public Child Eye Health Tertiary Facility for Pediatric Cataract in Southern Nigeria I: Visual Acuity Outcome

PubMed Central

Duke, Roseline E.; Adio, Adedayo; Oparah, Sidney K.; Odey, Friday; Eyo, Okon A.

2016-01-01

Purpose: A retrospective study of the outcome of congenital and developmental cataract surgery was conducted in a public child eye health tertiary facility in children <16 years of age in Southern Nigeria, as part of an evaluation. Materials and Method: Manual Small Incision Cataract Surgery with or without anterior vitrectomy was performed. The outcome measures were visual acuity (VA) and change (gain) in visual acuity. The age of the child at onset, duration of delay in presentation, ocular co-morbidity, non ocular co-morbidity, gender, and pre operative visual acuity were matched with postoperative visual acuity. A total of 66 children were studied for a period of six weeks following surgery. Results: Forty eight (72.7%) children had bilateral congenital cataracts and 18 (27.3%) children had bilateral developmental cataracts. There were 38(57.6%) males and 28 (42.4%) females in the study. Thirty Five (53%) children had good visual outcome (normal vision range 6/6/ -6/18) post-operatively. The number of children with blindness (vision <3/60) decreased from 61 (92.4%) pre-operatively to 4 (6.1%) post-operatively. Post operative complication occurred in 6.8% of cases six week after surgery. Delayed presentation had an inverse relationship with change (gain) in visual acuity (r = - 0.342; p-value = 0.005). Pre-operative visual acuity had a positive relationship with post operative change (gain) in visual acuity (r = 0.618; p-value = 0.000). Conclusion: Predictors of change in visual acuity in our study were; delayed presentation and pre-operative VA. Cataract surgery in children showed clinical benefit. PMID:27347247

Visual function and quality of life among visually impaired and cataract operated adults. The Pakistan National Blindness and Visual Impairment Survey.

PubMed

Taylor, Amy E; Shah, Shaheen P; Gilbert, Clare E; Jadoon, Mohammad Z; Bourne, Rupert R A; Dineen, Brendan; Johnson, Gordon J; Khan, Mohammad D

2008-01-01

To assess visual functioning and quality of life in a representative sample of normally sighted, visually impaired and cataract operated individuals aged >or= 30 years in Pakistan. As part of the Pakistan National Blindness and Visual Impairment Survey, visual functioning (VF) and quality of life (QOL) questionnaires were administered to participants with presenting visual acuity less than 6/60 in either eye, aphakes/pseudophakes and a phakic sample with normal acuity (>or= 6/12 both eyes). Of 16,507 adults included in the survey, 2329 questionnaires were administered. There were strong correlations between visual acuity and VF/QOL. Mean VF and median QOL scores in normally sighted phakic individuals were 81.1 and 88.9, respectively, but were only 34.8 and 64.9 in blind unoperated individuals. In the cataract operated population overall mean VF and median QOL scores were 49.3 and 75.0. Both VF and QOL scores were lower in operated individuals than unoperated individuals (p < 0.001). Among operated individuals, rural dwelling and illiteracy were associated with lower VF and QOL scores (p all < 0.02). Although in multivariable analysis bilateral pseudophakes had similar VF scores to bilateral aphakes they had significantly better QOL scores (p = 0.001). Cataract surgery in Pakistan has not led to VF and QOL scores equivalent to those in unoperated individuals with the same levels of visual acuity. The higher proportion of intraocular lens surgery in recent years is likely to improve QOL following cataract surgery. Further focus is needed on rural and illiterate populations, to ensure that they achieve comparable VF/QOL outcomes following surgery.

Object-processing neural efficiency differentiates object from spatial visualizers.

PubMed

Motes, Michael A; Malach, Rafael; Kozhevnikov, Maria

2008-11-19

The visual system processes object properties and spatial properties in distinct subsystems, and we hypothesized that this distinction might extend to individual differences in visual processing. We conducted a functional MRI study investigating the neural underpinnings of individual differences in object versus spatial visual processing. Nine participants of high object-processing ability ('object' visualizers) and eight participants of high spatial-processing ability ('spatial' visualizers) were scanned, while they performed an object-processing task. Object visualizers showed lower bilateral neural activity in lateral occipital complex and lower right-lateralized neural activity in dorsolateral prefrontal cortex. The data indicate that high object-processing ability is associated with more efficient use of visual-object resources, resulting in less neural activity in the object-processing pathway.

Selective Impairment of Living Things and Musical Instruments on a Verbal "Semantic Knowledge Questionnaire" in a Case of Apperceptive Visual Agnosia

ERIC Educational Resources Information Center

Masullo, Carlo; Piccininni, Chiara; Quaranta, Davide; Vita, Maria Gabriella; Gaudino, Simona; Gainotti, Guido

2012-01-01

Semantic memory was investigated in a patient (MR) affected by a severe apperceptive visual agnosia, due to an ischemic cerebral lesion, bilaterally affecting the infero-mesial parts of the temporo-occipital cortices. The study was made by means of a Semantic Knowledge Questionnaire (Laiacona, Barbarotto, Trivelli, & Capitani, 1993), which takes…

The Effect of Early Visual Deprivation on the Development of Face Detection

ERIC Educational Resources Information Center

Mondloch, Catherine J.; Segalowitz, Sidney J.; Lewis, Terri L.; Dywan, Jane; Le Grand, Richard; Maurer, Daphne

2013-01-01

The expertise of adults in face perception is facilitated by their ability to rapidly detect that a stimulus is a face. In two experiments, we examined the role of early visual input in the development of face detection by testing patients who had been treated as infants for bilateral congenital cataract. Experiment 1 indicated that, at age 9 to…

Perseverative Interference with Object-in-Place Scene Learning in Rhesus Monkeys with Bilateral Ablation of Ventrolateral Prefrontal Cortex

ERIC Educational Resources Information Center

Baxter, Mark G.; Browning, Philip G. F.; Mitchell, Anna S.

2008-01-01

Surgical disconnection of the frontal cortex and inferotemporal cortex severely impairs many aspects of visual learning and memory, including learning of new object-in-place scene memory problems, a monkey model of episodic memory. As part of a study of specialization within prefrontal cortex in visual learning and memory, we tested monkeys with…

Prevalence and causes of low vision and blindness in Baotou

PubMed Central

Zhang, Guisen; Li, Yan; Teng, Xuelong; Wu, Qiang; Gong, Hui; Ren, Fengmei; Guo, Yuxia; Liu, Lei; Zhang, Han

2016-01-01

Abstract The aim of this study was to investigate the prevalence and causes of low vision and blindness in Baotou, Inner Mongolia. A cross-sectional study was carried out. Multistage sampling was used to select samples. The visual acuity was estimated using LogMAR and corrected by pinhole as best-corrected visual acuity. There were 7000 samples selected and 5770 subjects included in this investigation. The overall bilateral prevalence rates of low vision and blindness were 3.66% (95% CI: 3.17–4.14) and 0.99% (95% CI: 0.73–1.24), respectively. The prevalence of bilateral low vision, blindness, and visual impairment increased with age and decreased with education level. The main leading cause of low vision and blindness was cataract. Diabetic retinopathy and age-related macular degeneration were found to be the second leading causes of blindness in Baotou. The low vision and blindness were more prevalent in elderly people and subjects with low education level in Baotou. Cataract was the main cause for visual impairment and more attention should be paid to fundus diseases. In order to prevent blindness, much more eye care programs should be established. PMID:27631267

Prevalence and causes of low vision and blindness in Baotou: A cross-sectional study.

PubMed

Zhang, Guisen; Li, Yan; Teng, Xuelong; Wu, Qiang; Gong, Hui; Ren, Fengmei; Guo, Yuxia; Liu, Lei; Zhang, Han

2016-09-01

The aim of this study was to investigate the prevalence and causes of low vision and blindness in Baotou, Inner Mongolia.A cross-sectional study was carried out. Multistage sampling was used to select samples. The visual acuity was estimated using LogMAR and corrected by pinhole as best-corrected visual acuity.There were 7000 samples selected and 5770 subjects included in this investigation. The overall bilateral prevalence rates of low vision and blindness were 3.66% (95% CI: 3.17-4.14) and 0.99% (95% CI: 0.73-1.24), respectively. The prevalence of bilateral low vision, blindness, and visual impairment increased with age and decreased with education level. The main leading cause of low vision and blindness was cataract. Diabetic retinopathy and age-related macular degeneration were found to be the second leading causes of blindness in Baotou.The low vision and blindness were more prevalent in elderly people and subjects with low education level in Baotou. Cataract was the main cause for visual impairment and more attention should be paid to fundus diseases. In order to prevent blindness, much more eye care programs should be established.

Visual outcomes of bilateral congenital and developmental cataracts in young children in south India and causes of poor outcome

PubMed Central

Khanna, Rohit C; Foster, Allen; Krishnaiah, Sannapaneni; Mehta, Manohar K; Gogate, Parikshit M

2013-01-01

Context: Bilateral pediatric cataracts are important cause of visual impairment in children. Aim: To study the outcome of bilateral pediatric cataract surgery in young children. Setting and Design: Retrospective case series in a tertiary center. Materials and Methods: Records of pediatric cataracts operated between January 2001 and December 2003, with a minimum follow-up of 3 months, were reviewed retrospectively. Statistical Methods: Independent sample t-test, Fisher's exact test, and logistic regression using SPSS (Statistical Package for Social Science, Chicago, USA) version 12. Results: 215/257 (83.7%) patients had a minimum follow-up of 3 months. The mean age of presentation to the hospital was 53 months (range: 0-168 months). Congenital cataract was present in 107 patients (58.2%) and developmental cataract in 77 patients (41.8%). The mean age at surgery was 55.2 months (range: 1-168 months). Out of 430 eyes, 269 (62.6%) had an intraocular lens implanted. The mean duration of follow-up was 13.1 months (range: 3-38 months). Pre-operatively, 102 patients (47.3%) had visual acuity <6/60, in the better eye, compared to 37 patients (17.2%) post-operatively (P < 0.001). Eighty-five patients (39.5%) had visual acuity >6/18. The most common early post-operative complication was fibrinous uveitis in 57 eyes (13.3%) and the most common delayed post-operative complication was posterior capsular opacification in 118 eyes (27.4%). The most important prognostic factor for poor outcome was congenital cataract (odds ratio [OR]: 26.3; 95% confidence interval [CI], 4.4-158.5) and total cataract (OR: 4.8; 95% CI, 1.3-17). PMID:23412523

Cortical network differences in the sighted versus early blind for recognition of human-produced action sounds

PubMed Central

Lewis, James W.; Frum, Chris; Brefczynski-Lewis, Julie A.; Talkington, William J.; Walker, Nathan A.; Rapuano, Kristina M.; Kovach, Amanda L.

2012-01-01

Both sighted and blind individuals can readily interpret meaning behind everyday real-world sounds. In sighted listeners, we previously reported that regions along the bilateral posterior superior temporal sulci (pSTS) and middle temporal gyri (pMTG) are preferentially activated when presented with recognizable action sounds. These regions have generally been hypothesized to represent primary loci for complex motion processing, including visual biological motion processing and audio-visual integration. However, it remained unclear whether, or to what degree, life-long visual experience might impact functions related to hearing perception or memory of sound-source actions. Using functional magnetic resonance imaging (fMRI), we compared brain regions activated in congenitally blind versus sighted listeners in response to hearing a wide range of recognizable human-produced action sounds (excluding vocalizations) versus unrecognized, backward-played versions of those sounds. Here we show that recognized human action sounds commonly evoked activity in both groups along most of the left pSTS/pMTG complex, though with relatively greater activity in the right pSTS/pMTG by the blind group. These results indicate that portions of the postero-lateral temporal cortices contain domain-specific hubs for biological and/or complex motion processing independent of sensory-modality experience. Contrasting the two groups, the sighted listeners preferentially activated bilateral parietal plus medial and lateral frontal networks, while the blind listeners preferentially activated left anterior insula plus bilateral anterior calcarine and medial occipital regions, including what would otherwise have been visual-related cortex. These global-level network differences suggest that blind and sighted listeners may preferentially use different memory retrieval strategies when attempting to recognize action sounds. PMID:21305666

Long-term postoperative outcomes after bilateral congenital cataract surgery in eyes with microphthalmos.

PubMed

Praveen, Mamidipudi R; Vasavada, Abhay R; Shah, Sajani K; Khamar, Mayuri B; Trivedi, Rupal H

2015-09-01

To evaluate the long-term impact of bilateral cataract surgery on postoperative complications, influence of age at surgery on the pattern of axial growth and central corneal thickness (CCT), and visual and orthoptic assessment in microphthalmic eyes. Iladevi Cataract and IOL Research Centre, Ahmedabad, India. Prospective longitudinal study. This study assessed children with microphthalmos who had bilateral congenital cataract surgery. Microphthalmos was defined as an eye that has an axial length (AL) that was 2 standard deviations smaller than what is normally expected at that age. All eyes were left aphakic. One of the 2 eyes was randomly selected for analysis. Postoperative complications, AL, CCT, and visual acuity were documented. This study included 72 eys of 36 children. The mean age of the patients was 4.8 months ± 6.2 (SD) (range 0.5 to 15 months). Postoperative complications included secondary glaucoma (11/36, 30.6%), visual axis obscuration (4/36, 11.1%), and posterior synechiae (10/36, 27.8%). A significant rate of change was observed in axial growth up to 4 years and in CCT up to 3 years postoperatively. When age at the time of surgery was correlated with the profile of the rate of change in AL and CCT at 1 month and 1, 2, and 4 years, statistically significant differences in AL and CCT at all timepoints were found. Loss of vision after surgery occurred in 2 eyes. After early surgical intervention, an acceptable rate of serious postoperative complications and good visual outcomes were obtained in microphthalmic eyes. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Temporal lobe developmental malformations and epilepsy: dual pathology and bilateral hippocampal abnormalities.

PubMed

Ho, S S; Kuzniecky, R I; Gilliam, F; Faught, E; Morawetz, R

1998-03-01

Temporal lobe developmental malformations (TLDM) with focal cortical dysplasia and balloon cells may coexist with mesial temporal sclerosis. The true incidence of this dual pathology is unknown. Our aim was to assess the frequency of amygdala (AM)-hippocampal abnormality in a homogeneous population with this specific developmental malformation. MRI-based volumetry of the AM and hippocampal formation (HF) in 30 patients with unilateral TLDM and intractable partial epilepsy was performed. A volume normalization process defined a normal range of HF and AM volumes in control subjects, and enabled the detection of bilateral volume loss. Normalized volumes detected HF atrophy in 26 patients (nine unilateral and 17 bilateral) and AM atrophy in 18 patients (three unilateral and 15 bilateral). Visual analysis detected unilateral HF abnormality in 21 patients and bilateral abnormality in two. When compared with a group of patients with temporal lobe epilepsy and pure hippocampal sclerosis (N = 92), where volumetry revealed bilateral HF atrophy in 18%, a significant difference in the frequency of bilateral HF atrophy was found (p < 0.0001). Dual pathology is frequent in patients with TLDM (87%), and the AM-HF abnormality is often bilateral (57%). Our data suggest that more widespread and potentially epileptogenic lesions coexist with visibly detectable unilateral TLDM. This has implications for the selection of patients for temporal lobe surgery and may influence surgical strategies.

Foveal damage in habitual poppers users.

PubMed

Audo, Isabelle; El Sanharawi, Mohamed; Vignal-Clermont, Catherine; Villa, Antoine; Morin, Annie; Conrath, John; Fompeydie, Dominique; Sahel, José-Alain; Gocho-Nakashima, Kiyoko; Goureau, Olivier; Paques, Michel

2011-06-01

To describe foveal damage in habitual use of poppers, a popular recreational drug. Retrospective observational case series. Six patients with bilateral vision loss after chronic popper inhalation were seen in 4 university-based ophthalmology departments. Symptoms, medical history, ophthalmic examination, and functional and morphological tests are described. All patients experienced progressive bilateral vision loss, with central photopsia in 2 cases. Initial visual acuities ranged from 20/50 to 20/25. In all patients, a bilateral yellow foveal spot was present that, by optical coherence tomography, was associated with disruption of the outer segments of foveal cones. Functional and anatomical damage was restricted to the fovea. The poppers involved were identified as isopropyl nitrite in 3 cases. Four patients showed anatomical and/or functional improvement over several months after discontinuing popper inhalation. Repeated inhalation of poppers may be associated with prolonged bilateral vision loss due to the disruption of foveal cone outer segments. Retinal damage may progressively improve following drug discontinuation.

Bilateral optic neuritis in pediatric systemic lupus erythematosus with antiphospholipid antibody syndrome.

PubMed

Patra, Soumya; Krishnamurthy, Sriram; Seth, Anju; Beri, Sarita; Aneja, Satinder

2011-02-01

Bilateral optic neuritis is an extremely uncommon complication of pediatric systemic lupus erythematosus and sporadic cases are reported in the literature. The authors describe an 11-yr-old girl who presented with fever and progressively increasing pallor for 4 months, headache for 7 days, severe anemia and hepatosplenomegaly. Soon after admission, she developed rapid deterioration of vision, worsening to no perception of light with afferent pupillary defect. Fundoscopy showed bilateral optic neuritis. Investigations revealed autoimmune hemolytic anemia and thrombocytopenia. Anti-dsDNA and anti-phospholipid antibodies were positive. Magnetic resonance venography showed multiple thrombi in the cerebral venous sinuses, for which anticoagulant therapy was initiated. She was managed with intravenous methylprednisolone followed by cyclophosphamide pulse therapy for 6 months along with oral prednisolone. Though she went into remission, visual outcome has been dismal, with development of bilateral optic atrophy, and absence of perception of light.

Characteristics of choroidal neovascularization in the complications of age-related macular degeneration prevention trial.

PubMed

Maguire, Maureen G; Alexander, Judith; Fine, Stuart L

2008-09-01

To describe the characteristics of incident choroidal neovascularization (CNV) in observed and treated eyes in the Complications of Age-related Macular Degeneration Prevention Trial (CAPT). Cross-sectional descriptive study within a multicenter, randomized clinical trial. Patients who developed CNV during CAPT follow-up. Inclusion criteria for CAPT specified bilateral large drusen (>or=10 drusen at least 125 micro), visual acuity >or=20/40 in each eye, and age >or=50. Exclusion criteria included CNV and geographic atrophy >1 Macular Photocoagulation Study (MPS) disc area or within 500 micro of the foveal center. One eye of each person was selected randomly for low-intensity laser treatment and the contralateral eye was observed. Fluorescein angiography was performed at baseline, annually for >or=5 years, and whenever there were symptoms of CNV. Trained readers at the CAPT Photograph Reading Center assessed color stereo photographs and angiogram negatives to identify CNV. Choroidal neovascularization was classified by type (predominantly classic CNV, minimally classic CNV, occult only CNV, or scar), location, and area. Visual acuity was measured by certified examiners. Symmetry of characteristics between eyes of bilaterally affected patients was examined. Choroidal neovascularization developed in 282 eyes of 225 patients. At the time of detection, 192 (68%) of the lesions were occult only, 153 (54%) were subfoveal, and 157 (56%) were or=20/40 in 123 (69%) of 179 eyes with visual acuity measured at the time of detection. Choroidal neovascularization developed in both eyes in 57 patients (25%) during CAPT follow-up. Lesions in eyes of bilaterally affected patients were no more similar to each other than affected eyes in 2 different patients. When patients are monitored closely, many CNV lesions can be detected outside of the fovea and when they are relatively small. Early detection may lead to improved long-term visual acuity.

[Postoperative visual loss due to conversion disorder after spine surgery: a case report].

PubMed

Bezerra, Dailson Mamede; Bezerra, Eglantine Mamede; Silva Junior, Antonio Jorge; Amorim, Marco Aurélio Soares; Miranda, Denismar Borges de

Patients undergoing spinal surgeries may develop postoperative visual loss. We present a case of total bilateral visual loss in a patient who, despite having clinical and surgical risk factors for organic lesion, evolved with visual disturbance due to conversion disorder. A male patient, 39 years old, 71kg, 1.72 m, ASA I, admitted to undergo fusion and discectomy at L4-L5 and L5-S1. Venoclysis, cardioscopy, oximetry, NIBP; induction with remifentanil, propofol and rocuronium; intubation with ETT (8.0mm) followed by capnography and urinary catheterization for diuresis. Maintenance with full target-controlled intravenous anesthesia. During fixation and laminectomy, the patient developed severe bleeding and hypovolemic shock. After 30minutes, hemostasis and hemodynamic stability was achieved with infusion of norepinephrine, volume expansion, and blood products. In the ICU, the patient developed mental confusion, weakness in the limbs, and bilateral visual loss. It was not possible to identify clinical, laboratory or image findings of organic lesion. He evolved with episodes of anxiety, emotional lability, and language impairment; the hypothesis of conversion syndrome with visual component was raised after psychiatric evaluation. The patient had complete resolution of symptoms after visual education and introduction of low doses of antipsychotic, antidepressant, and benzodiazepine. Other symptoms also regressed, and the patient was discharged 12 days after surgery. After 60 days, the patient had no more symptoms. Conversion disorders may have different signs and symptoms of non-organic origin, including visual component. It is noteworthy that the occurrence of this type of visual dysfunction in the postoperative period of spinal surgery is a rare event and should be remembered as a differential diagnosis. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

Fatigue, quality of life and walking ability in adults with cerebral palsy.

PubMed

Lundh, Sofia; Nasic, Salmir; Riad, Jacques

2018-03-01

Few studies on fatigue, quality of life and walking ability in adults with cerebral palsy (CP) are available. It is unclear whether these variables are associated. The aim was to study the influence of CP on fatigue, quality of life, and gait of adult patients. Three-dimensional gait analysis was performed on 24 women and 26 men, mean age 32.1 (range 21.7-67.2), 23 with unilateral and 27 with bilateral CP. The Gait Profile Score was calculated; Fatigue Severity and EQ Visual Analogue scales were used. Fatigue severity was higher than in controls, mean 3.8 (SD 1.8) vs 3.0 (p = 0.012). Fatigue in the unilateral group was 3.3 (SD 1.8) and in the bilateral 4.2 (SD 1.7), (p = 0.07). EQ Visual Analogue scale in the unilateral group was mean 79.5 (21.9) and in the bilateral 64.0 (20.8), p = 0.007. The group with bilateral CP tended toward crouch gait, decreased balance and low walking speed. Muscle work was shifted from the ankle to hip muscles. Fatigue correlated with the Gait Profile Score, CC = 0.31 (p = 0.038), and with knee flexion deviation, CC = 0.31 (p = 0.037). Crouch gait, increased knee flexion in stance, contributes to increased deviation in the lower extremity associated with high fatigue and low quality of life in adults with CP, effects more pronounced in those with bilateral CP. Compensation mechanisms in gait were noted. Rational follow-up programs for CP, ideally identifying risk factors early, should be established to prevent development of fatigue and deterioration of gait in adulthood. Copyright © 2017 Elsevier B.V. All rights reserved.

Clinical Evaluation of Hyaluronic Acid Sponge with Zinc versus Placebo for Scar Reduction after Breast Surgery

PubMed Central

Mahedia, Monali; Shah, Nilay

2016-01-01

Background: Scar formation is a major source of dissatisfaction among patients and surgeons. Individually, hyaluronan, or hyaluronic acid (HA), and zinc have been shown to reduce scarring. The authors evaluated the safety and efficacy of an HA sponge with zinc compared with placebo when applied to bilateral breast surgery scars; specifically, they evaluated whether the use of this product modulates inflammation and immediate scarring in treated patients after bilateral breast surgery. Methods: This double-blind, randomized, prospective study was approved by the local institutional review board. Bilateral breast surgery patients with right and left incision lines were randomly assigned to receive HA sponge with zinc or placebo within 2 to 4 days after their procedure. Participants were followed up at 6 weeks, 12 weeks, and 1 year and evaluated at 12 weeks. Three blinded evaluators reviewed photographs of the incision lines and assessed the scars using a visual analog scale, new scale, and a patient satisfaction survey. Results: Nineteen bilateral breast surgery patients were enrolled in the study. Statistical analysis was performed on 14 patients who completed the follow-up. The mean visual analog scale score was lower for the side receiving the HA sponge with zinc (2.6) than for the side receiving placebo (3.0), indicating a better outcome (t test; P = 0.08). The HA sponge with zinc was found to have significant positive findings on a patient satisfaction survey (P = 0.01). Conclusions: This is a preliminary study that shows zinc hyaluronan was associated with high patient satisfaction in achieving a better scar after bilateral breast surgery, irrespective of skin color. It seems to be safe and effective for early scars. PMID:27536470

Braille alexia during visual hallucination in a blind man with selective calcarine atrophy.

PubMed

Maeda, Kengo; Yasuda, Hitoshi; Haneda, Masakazu; Kashiwagi, Atsunori

2003-04-01

The case of a 56-year-old man who has been blind for 25 years due to retinal degeneration is herein described. The patient complained of elementary visual hallucination, during which it was difficult for him to read Braille. Brain magnetic resonance imaging showed marked atrophy of the bilateral striate cortex. Visual hallucination as a release phenomenon of the primary visual cortex has never been reported to cause alexia for Braille. The present case supports the results of recent functional imaging studies of the recruitment of striate and prestriate cortex for Braille reading.

Early treatment with infliximab in bilateral occlusive vasculitis as a presenting manifestation of Behçet' disease.

PubMed

Bañeros-Rojas, P; Berrozpe-Villabona, C; Peraza-Nieves, J E; Díaz-Valle, D

2015-06-01

A 24 year old woman who complained of maculo-papulo rash, genital and bucal aphthous ulcers, abdominal pain, minor dyspnea and visual loss in both eyes. Funduscopy revealed a bilateral occlusive vasculitis including central vessels. Treatment was initiated with a methylprednisolone bolus (1 g/24h) and infliximab 5mg/kg/day (0-2-6 weeks and every 8 weeks). The treatment prescribed induced a fast remission. Visual acuity improved. The patient did not suffer any other relapse after one year of follow-up. An initial treatment with Infliximab should be considered in Behçet disease for serious outbreaks, such as macular occlusive vasculitis with ischemia. Copyright © 2013 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

Dense pigmentation of the posterior lens capsule associated with the pigment dispersion syndrome.

PubMed

Lin, Danny Y; Volpicelli, Mark; Singh, Kuldev

2003-12-01

To report an unusual case of pigment dispersion syndrome associated with unilateral dense pigmentation of the posterior lens capsule. Case report. A 59-year-old male with bilateral pigment dispersion syndrome presented with progressive decrease in visual acuity in the left eye over the past 10 to 20 years. Clinical examination revealed the typical findings of pigment dispersion syndrome including the presence of bilateral Krunkenberg spindles, iris transillumination defects, and heavy trabecular meshwork pigmentation. Of note, there was remarkably dense pigmentation of the posterior lens capsule in the eye with decreased visual acuity. Pigmentation of the posterior lens capsule may be a rare finding associated with pigment dispersion syndrome. Such a finding suggests that there may be aqueous flow into the retrolental space in some patients with this condition. The optimal treatment of this unusual condition remains undetermined.

Bilateral foveal retinoschisis accompanying unilateral peripheral retinoschisis.

PubMed

Kocak, Nilufer; Ozturk, Taylan A; Kaynak, Suleyman

2014-04-01

X-linked juvenile retinoschisis is a rare hereditary retinal disease characterized by a tangential splitting of the neurosensory retina which may cause early-onset visual impairment. Existence of the retinal neurosensory layer splitting on cross-sectional images of optical coherance tomography (OCT) and the absence of leakage on fluorescein angiography (FA) help confirming the diagnosis. Such diagnostic tests are also helpful in determining the management of the disease. However, most of the retinoschisis cavities remain stable and rarely extend to the posterior pole, many authors suggest laser prophylaxis to avoid the potential risk of retinal detachment due to holes in the outer retinal layer. Herein, we report a case with bilateral foveal retinoschisis accompanying unilateral peripheral retinoschisis who was evaluated with detailed ophthalmologic examination. Visual acuity, fundoscopy, OCT, and FA remained stable in the second year of follow-up after prophylactic argon laser treatment.

Simultaneous Bilateral Cataract Surgery in Outreach Surgical Camps

PubMed Central

Giles, Kagmeni; Robert, Ebana Steve; Come, Ebana Mvogo; Wiedemann, Peter

2017-01-01

OBJECTIVES The aim of this study was to evaluate the safety and visual outcomes of simultaneous bilateral cataract surgery (SBCS) with intraocular lens implantation performed in outreach surgical eye camps. METHODS The medical records of 47 consecutive patients who underwent simultaneous bilateral small-incision cataract surgery between January 2010 and December 2015 in outreach surgical camps in rural Cameroon were reviewed. The measures included postoperative visual outcomes and intraoperative and postoperative complications. RESULTS Data from 94 eyes of 47 participants (30 men, 17 women; mean age: 60.93 ± 13.58 years, range: 45–80 years) were included in this study. The presented best visual acuity (VA) was less than 3/60 in 100% of the eyes. At the 4-week follow-up, 84.04% of the eyes showed increased VA of 1 line or more (P = .001). Of these, 71 (75.53%) achieved good VA (greater than 6/18). Intraoperative or postoperative complications occurred in 19 (20.21%) eyes. The most serious intraoperative complication was a posterior capsule rupture and vitreous loss (2 patients, 2 eyes). The postoperative complications included a transient elevation in the intraocular pressure (6 eyes), chronic corneal oedema (5 eyes), iris capture (3 eyes), lens decentration (2 eyes), and hyphema (1 eye). No cases of postoperative endophthalmitis were recorded. CONCLUSIONS Under the strict observation of endophthalmitis prophylaxis, SBCS is an option to reduce the cataract blindness backlog in rural areas of developing countries. PMID:28469481

Neural Substrates of Visual Spatial Coding and Visual Feedback Control for Hand Movements in Allocentric and Target-Directed Tasks

PubMed Central

Thaler, Lore; Goodale, Melvyn A.

2011-01-01

Neuropsychological evidence suggests that different brain areas may be involved in movements that are directed at visual targets (e.g., pointing or reaching), and movements that are based on allocentric visual information (e.g., drawing or copying). Here we used fMRI to investigate the neural correlates of these two types of movements in healthy volunteers. Subjects (n = 14) performed right hand movements in either a target-directed task (moving a cursor to a target dot) or an allocentric task (moving a cursor to reproduce the distance and direction between two distal target dots) with or without visual feedback about their hand movement. Movements were monitored with an MR compatible touch panel. A whole brain analysis revealed that movements in allocentric conditions led to an increase in activity in the fundus of the left intra-parietal sulcus (IPS), in posterior IPS, in bilateral dorsal premotor cortex (PMd), and in the lateral occipital complex (LOC). Visual feedback in both target-directed and allocentric conditions led to an increase in activity in area MT+, superior parietal–occipital cortex (SPOC), and posterior IPS (all bilateral). In addition, we found that visual feedback affected brain activity differently in target-directed as compared to allocentric conditions, particularly in the pre-supplementary motor area, PMd, IPS, and parieto-occipital cortex. Our results, in combination with previous findings, suggest that the LOC is essential for allocentric visual coding and that SPOC is involved in visual feedback control. The differences in brain activity between target-directed and allocentric visual feedback conditions may be related to behavioral differences in visual feedback control. Our results advance the understanding of the visual coordinate frame used by the LOC. In addition, because of the nature of the allocentric task, our results have relevance for the understanding of neural substrates of magnitude estimation and vector coding of movements. PMID:21941474

The Role of Anterior Nuclei of the Thalamus: A Subcortical Gate in Memory Processing: An Intracerebral Recording Study

PubMed Central

Štillová, Klára; Jurák, Pavel; Chládek, Jan; Chrastina, Jan; Halámek, Josef; Bočková, Martina; Goldemundová, Sabina; Říha, Ivo; Rektor, Ivan

2015-01-01

Objective To study the involvement of the anterior nuclei of the thalamus (ANT) as compared to the involvement of the hippocampus in the processes of encoding and recognition during visual and verbal memory tasks. Methods We studied intracerebral recordings in patients with pharmacoresistent epilepsy who underwent deep brain stimulation (DBS) of the ANT with depth electrodes implanted bilaterally in the ANT and compared the results with epilepsy surgery candidates with depth electrodes implanted bilaterally in the hippocampus. We recorded the event-related potentials (ERPs) elicited by the visual and verbal memory encoding and recognition tasks. Results P300-like potentials were recorded in the hippocampus by visual and verbal memory encoding and recognition tasks and in the ANT by the visual encoding and visual and verbal recognition tasks. No significant ERPs were recorded during the verbal encoding task in the ANT. In the visual and verbal recognition tasks, the P300-like potentials in the ANT preceded the P300-like potentials in the hippocampus. Conclusions The ANT is a structure in the memory pathway that processes memory information before the hippocampus. We suggest that the ANT has a specific role in memory processes, especially memory recognition, and that memory disturbance should be considered in patients with ANT-DBS and in patients with ANT lesions. ANT is well positioned to serve as a subcortical gate for memory processing in cortical structures. PMID:26529407

Anisotropy of Human Horizontal and Vertical Navigation in Real Space: Behavioral and PET Correlates.

PubMed

Zwergal, Andreas; Schöberl, Florian; Xiong, Guoming; Pradhan, Cauchy; Covic, Aleksandar; Werner, Philipp; Trapp, Christoph; Bartenstein, Peter; la Fougère, Christian; Jahn, Klaus; Dieterich, Marianne; Brandt, Thomas

2016-10-17

Spatial orientation was tested during a horizontal and vertical real navigation task in humans. Video tracking of eye movements was used to analyse the behavioral strategy and combined with simultaneous measurements of brain activation and metabolism ([18F]-FDG-PET). Spatial navigation performance was significantly better during horizontal navigation. Horizontal navigation was predominantly visually and landmark-guided. PET measurements indicated that glucose metabolism increased in the right hippocampus, bilateral retrosplenial cortex, and pontine tegmentum during horizontal navigation. In contrast, vertical navigation was less reliant on visual and landmark information. In PET, vertical navigation activated the bilateral hippocampus and insula. Direct comparison revealed a relative activation in the pontine tegmentum and visual cortical areas during horizontal navigation and in the flocculus, insula, and anterior cingulate cortex during vertical navigation. In conclusion, these data indicate a functional anisotropy of human 3D-navigation in favor of the horizontal plane. There are common brain areas for both forms of navigation (hippocampus) as well as unique areas such as the retrosplenial cortex, visual cortex (horizontal navigation), flocculus, and vestibular multisensory cortex (vertical navigation). Visually guided landmark recognition seems to be more important for horizontal navigation, while distance estimation based on vestibular input might be more relevant for vertical navigation. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Prism adaptation enhances activity of intact fronto-parietal areas in both hemispheres in neglect patients.

PubMed

Saj, Arnaud; Cojan, Yann; Vocat, Roland; Luauté, Jacques; Vuilleumier, Patrik

2013-01-01

Unilateral spatial neglect involves a failure to report or orient to stimuli in the contralesional (left) space due to right brain damage, with severe handicap in everyday activities and poor rehabilitation outcome. Because behavioral studies suggest that prism adaptation may reduce spatial neglect, we investigated the neural mechanisms underlying prism effects on visuo-spatial processing in neglect patients. We used functional magnetic resonance imaging (fMRI) to examine the effect of (right-deviating) prisms on seven patients with left neglect, by comparing brain activity while they performed three different spatial tasks on the same visual stimuli (bisection, search, and memory), before and after a single prism-adaptation session. Following prism adaptation, fMRI data showed increased activation in bilateral parietal, frontal, and occipital cortex during bisection and visual search, but not during the memory task. These increases were associated with significant behavioral improvement in the same two tasks. Changes in neural activity and behavior were seen only after prism adaptation, but not attributable to mere task repetition. These results show for the first time the neural substrates underlying the therapeutic benefits of prism adaptation, and demonstrate that visuo-motor adaptation induced by prism exposure can restore activation in bilateral brain networks controlling spatial attention and awareness. This bilateral recruitment of fronto-parietal networks may counteract the pathological biases produced by unilateral right hemisphere damage, consistent with recent proposals that neglect may reflect lateralized deficits induced by bilateral hemispheric dysfunction. Copyright © 2011 Elsevier Ltd. All rights reserved.

Optic neuritis with positive HLA-B27: Characteristic phenotype in the Chinese population.

PubMed

Zhao, Shuo; Zhou, Huanfen; Peng, Xudong; Zhu, Jian; Wang, Wei; Kang, Hao; Chen, Tingjun; Xu, Quangang; Wei, Shihui

2016-03-15

This study retrospectively reviewed the clinical features of optic neuritis (ON) with positive HLA-B27. Clinical data were reviewed for HLA-B27-positive ON in the Chinese People's Liberation Army General Hospital from January 2009 through June 2015. The prevalence of HLA-B27 and spondyloarthropathies was analyzed. Clinical features of HLA-B27-positive ON based on serum aquaporin 4-antibody (AQP4-Ab) were compared. A total of 22 ON patients (14 female/8 male, 38 involved eyes) with positive HLA-B27 were collected from 410 ON patients. Recurrent episodes were observed in 14/22 patients, and seven patients presented as bilateral simultaneous ON. A total of 68.4% (22/38) of involved eyes exhibited severe visual impairment (<0.1) at onset. A total of 8/22 patients were seropositive for AQP4-Ab, and clinical features did not differ based on AQP4-Ab status. Bilateral sacroiliitis was revealed in over 50% (7/13) of patients screened using pelvic computed tomography. Three patients were diagnosed with ankylosing spondylitis (AS), and one patient experienced co-occurrence of active AS and bilateral ON. HLA-B27-positive ON may presented recurrent episodes and severe visual impairment at onset. The co-occurrence of ON and AS, and the frequent presence of bilateral sacroiliitis may indicate an underlying alternation of autoimmune background in this condition. Copyright © 2016 Elsevier B.V. All rights reserved.

Dorsolateral prefrontal cortex bridges bilateral primary somatosensory cortices during cross-modal working memory.

PubMed

Zhao, Di; Ku, Yixuan

2018-05-01

Neural activity in the dorsolateral prefrontal cortex (DLPFC) has been suggested to integrate information from distinct sensory areas. However, how the DLPFC interacts with the bilateral primary somatosensory cortices (SIs) in tactile-visual cross-modal working memory has not yet been established. In the present study, we applied single-pulse transcranial magnetic stimulation (sp-TMS) over the contralateral DLPFC and bilateral SIs of human participants at various time points, while they performed a tactile-visual delayed matching-to-sample task with a 2-second delay. sp-TMS over the contralateral DLPFC or the contralateral SI at either an sensory encoding stage [i.e. 100 ms after the onset of a vibrotactile sample stimulus (200-ms duration)] or an early maintenance stage (i.e. 300 ms after the onset), significantly impaired the accuracy of task performance; sp-TMS over the contralateral DLPFC or the ipsilateral SI at a late maintenance stage (1600 ms and 1900 ms) also significantly disrupted the performance. Furthermore, at 300 ms after the onset of the vibrotactile sample stimulus, there was a significant correlation between the deteriorating effects of sp-TMS over the contralateral SI and the contralateral DLPFC. These results imply that the DLPFC and the bilateral SIs play causal roles at distinctive stages during cross-modal working memory, while the contralateral DLPFC communicates with the contralateral SI in the early delay, and cooperates with the ipsilateral SI in the late delay. Copyright © 2018 Elsevier B.V. All rights reserved.

Hyperhomocysteinemia in bilateral anterior ischemic optic neuropathy after conventional coronary artery bypass graft: a case report.

PubMed

Niro, A; Sborgia, G; Sborgia, A; Alessio, G

2018-01-17

The incidence of anterior ischemic optic neuropathy after coronary artery bypass graft procedures ranges from 1.3 to 0.25%. The mechanisms of anterior ischemic optic neuropathy after cardiovascular procedures remain undefined but many systemic and related-to-surgery risk factors could underlie anterior ischemic optic neuropathy. In this case, we report a rare presentation of a bilateral anterior ischemic optic neuropathy after coronary artery bypass graft and speculate on the preoperative hyperhomocysteinemia as an independent risk factor for anterior ischemic optic neuropathy. A 56-year-old white man, a tobacco smoker with type 2 diabetes and coronary artery disease, underwent a conventional coronary artery bypass graft with extracorporeal circulation. In spite of ongoing anti-aggregation, antithrombotic, and vasodilator therapy, 10 days after the surgery he complained of severe bilateral visual loss. Funduscopy and fluorescein angiography revealed a bilateral anterior ischemic optic neuropathy. Analysis of preoperative laboratory tests revealed hyperhomocysteinemia. Hyperhomocysteinemia could increase the risk of ocular vascular damage and bilateral ocular involvement in patients who have undergone conventional coronary artery bypass graft.

Thinking about eating food activates visual cortex with reduced bilateral cerebellar activation in females with anorexia nervosa: an fMRI study.

PubMed

Brooks, Samantha J; O'Daly, Owen; Uher, Rudolf; Friederich, Hans-Christoph; Giampietro, Vincent; Brammer, Michael; Williams, Steven C R; Schiöth, Helgi B; Treasure, Janet; Campbell, Iain C

2012-01-01

Women with anorexia nervosa (AN) have aberrant cognitions about food and altered activity in prefrontal cortical and somatosensory regions to food images. However, differential effects on the brain when thinking about eating food between healthy women and those with AN is unknown. Functional magnetic resonance imaging (fMRI) examined neural activation when 42 women thought about eating the food shown in images: 18 with AN (11 RAN, 7 BPAN) and 24 age-matched controls (HC). Group contrasts between HC and AN revealed reduced activation in AN in the bilateral cerebellar vermis, and increased activation in the right visual cortex. Preliminary comparisons between AN subtypes and healthy controls suggest differences in cortical and limbic regions. These preliminary data suggest that thinking about eating food shown in images increases visual and prefrontal cortical neural responses in females with AN, which may underlie cognitive biases towards food stimuli and ruminations about controlling food intake. Future studies are needed to explicitly test how thinking about eating activates restraint cognitions, specifically in those with restricting vs. binge-purging AN subtypes.

Bilateral foveal cysts secondary to Streptococcus constellatus endocarditis.

PubMed

Shah, Anish N; Shah, Benoy N; Glover, Sarah; Herbert, Luke

2013-06-01

Infective endocarditis can be acute or subacute, depending on the virulence of the causative organism. It can also cause loss of vision by a variety of mechanisms, ranging from embolic retinal artery occlusion to endogenous endophthalmitis. We illustrate the first report of foveal cyst formation secondary to infective endocarditis. A 53-year-old man presented to his general practitioner with a variety of constitutional symptoms, but initial laboratory and imaging investigations revealed only mild normocytic anaemia, and he was discharged from further medical care. Four weeks later he developed bilateral visual loss associated with whitish lesions of the superficial retina at both foveae. These later developed into foveal cysts with disruption of the photoreceptor inner segment-outer segment junction and persistent poor visual acuity of 6/60 OU. No retinal haemorrhages or Roth spots were noted. Only after he presented with visual loss did further investigations reveal the underlying diagnosis of streptococcal endocarditis. Ophthalmologists assessing retinal pathology which presents in association with undiagnosed constitutional symptoms are advised to refer such patients promptly for thorough medical investigation, including blood culture and echocardiography where appropriate.

Pattern of retinal diseases at a teaching eye department, Addis Ababa, Ethiopia.

PubMed

Teshome, Tiliksew; Melaku, Solomon; Bayu, Samson

2004-07-01

The purpose of this study was to evaluate the pattern of retinal diseases as seen at a teaching and tertiary eye care center in Addis Ababa. In a descriptive, cross-sectional study, all consecutive patients seen at the retina clinic of Menelik II Hospital during a 19 months period (January 2000 to August 2001) were included in this series. Pertinent demographic and clinical data were recorded for all patients. A total of 1390 new patients with retinal diseases were seen at the retina clinic during the study period, accounting for 12.5% of the total outpatient population of the eye department. The male to female ratio was 1.8 : 1. The mean age was 45.2 years +/- 17.3 years (range 2 months to 92 years) and median of 44.5 years. Two hundred and twenty-four (16.1%) patients were bilaterally blind, 465 (33.5%) patients were unilaterally blind, 280 (20.1%) patients had bilateral visual impairment and 195 (14.0%) patients had unilateral visual impairment, while 213 (15.3%) patients had normal vision. Retinal detachment was the commonest cause of both bilateral (54.9%) and unilateral blindness (41.2%), while diabetic retinopathy and myopia were the leading causes of bilateral visual impairment accounting for 36.8% and 28.2% respectively. Retinal vascular diseases accounted for the largest group of patients (38.1%) of which diabetic retinopathy accounted for 75.1%. Retinal detachment was the second largest group of diseases, accounting for 24.5% of the total. The proportion of patients with age-related macular degeneration was only 2.7%. Most of the patients presented with advanced disease, which required vitreo-retinal surgery. There is a need to improve on the early diagnosis and early referral of retinal diseases at primary and secondary care levels. Selected tertiary care centers should develop capacity to provide laser and vitreo-retinal surgery. The introduction of posterior vitrectomy in Ethiopia is long overdue.

Long-term Outcomes of Cytomegalovirus Retinitis in the Era of Modern Antiretroviral Therapy; Results from a United States Cohort

PubMed Central

Jabs, Douglas A.; Ahuja, Alka; Van Natta, Mark L.; Lyon, Alice T.; Yeh, Steven; Danis, Ronald

2015-01-01

Objectives To describe the long-term outcomes of patients with cytomegalovirus (CMV) retinitis and the acquired immunodeficiency syndrome (AIDS)in the modern era of combination antiretroviral therapy. Design Prospective, observational, cohort study Participants Patients with AIDS and CMV retinitis Testing Immune recovery, defined as a CD4+ T cell count>100 cells/μL for ≥ 3 months. Main outcome measures Mortality, visual impairment (visual acuity worse than 20/40) and blindness (visual acuity 20/200 or worse) on logarithmic visual acuity charts, loss of visual field on quantitative Goldmann perimetry. Results Patients without immune recovery had a mortality of 44.4/100 person years (PY), and a median survival of 13.5 months after the diagnosis of CMV retinitis, whereas those with immune recovery had a mortality of 2.7/100 PY (P<0.001), and an estimated median survival of 27.0 years after the diagnosis of CMV retinitis. The rates of bilateral visual impairment and blindness were 0.9/100 PY and 0.4/100 PY, respectively, and were similar between those with and without immune recovery. Among those with immune recovery, the rate of visual field loss was ~1% of the normal field/year, whereas among those without immune recovery it was ~7% of the normal field/year. Conclusions Among persons with CMV retinitis and AIDS, if there is immune recovery, long-term survival is likely, whereas if there is no immune recovery, the mortality rate is substantial. Although higher than the rates seen in the non-HIV-infected population, the rates of bilateral visual impairment and blindness are low, especially when compared to rates seen in the era before modern antiretroviral therapy. PMID:25892019

Long-term Outcomes of Cytomegalovirus Retinitis in the Era of Modern Antiretroviral Therapy: Results from a United States Cohort.

PubMed

Jabs, Douglas A; Ahuja, Alka; Van Natta, Mark L; Lyon, Alice T; Yeh, Steven; Danis, Ronald

2015-07-01

To describe the long-term outcomes of patients with cytomegalovirus (CMV) retinitis and AIDS in the modern era of combination antiretroviral therapy. Prospective, observational cohort study. Patients with AIDS and CMV retinitis. Immune recovery, defined as a CD4+ T-cell count >100 cells/μl for ≥3 months. Mortality, visual impairment (visual acuity <20/40), and blindness (visual acuity ≤20/200) on logarithmic visual acuity charts and loss of visual field on quantitative Goldmann perimetry. Patients without immune recovery had a mortality of 44.4/100 person-years (PYs) and a median survival of 13.5 months after the diagnosis of CMV retinitis, whereas those with immune recovery had a mortality of 2.7/100 PYs (P < 0.001) and an estimated median survival of 27.0 years after the diagnosis of CMV retinitis. The rates of bilateral visual impairment and blindness were 0.9 and 0.4/100 PYs, respectively, and were similar between those with and without immune recovery. Among those with immune recovery, the rate of visual field loss was approximately 1% of the normal field per year, whereas among those without immune recovery it was approximately 7% of the normal field per year. Among persons with CMV retinitis and AIDS, if there is immune recovery, long-term survival is likely, whereas if there is no immune recovery, the mortality rate is substantial. Although higher than the rates in the population not infected by human immunodeficiency virus, the rates of bilateral visual impairment and blindness are low, especially when compared with rates in the era before modern antiretroviral therapy. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Does visual working memory represent the predicted locations of future target objects? An event-related brain potential study.

PubMed

Grubert, Anna; Eimer, Martin

2015-11-11

During the maintenance of task-relevant objects in visual working memory, the contralateral delay activity (CDA) is elicited over the hemisphere opposite to the visual field where these objects are presented. The presence of this lateralised CDA component demonstrates the existence of position-dependent object representations in working memory. We employed a change detection task to investigate whether the represented object locations in visual working memory are shifted in preparation for the known location of upcoming comparison stimuli. On each trial, bilateral memory displays were followed after a delay period by bilateral test displays. Participants had to encode and maintain three visual objects on one side of the memory display, and to judge whether they were identical or different to three objects in the test display. Task-relevant memory and test stimuli were located in the same visual hemifield in the no-shift task, and on opposite sides in the horizontal shift task. CDA components of similar size were triggered contralateral to the memorized objects in both tasks. The absence of a polarity reversal of the CDA in the horizontal shift task demonstrated that there was no preparatory shift of memorized object location towards the side of the upcoming comparison stimuli. These results suggest that visual working memory represents the locations of visual objects during encoding, and that the matching of memorized and test objects at different locations is based on a comparison process that can bridge spatial translations between these objects. This article is part of a Special Issue entitled SI: Prediction and Attention. Copyright © 2014 Elsevier B.V. All rights reserved.

Bilateral childhood visual impairment: child and parent concerns.

PubMed

Liebermann, Laura; Leske, David A; Hatt, Sarah R; Castañeda, Yolanda S; Wernimont, Suzanne M; Cheng-Patel, Christina S; Birch, Eileen E; Holmes, Jonathan M

2017-06-01

To identify specific health-related quality of life and visual function concerns affecting children with bilateral visual impairment as expressed by children or one of their parents (proxy) and concerns affecting the parents themselves. A total of 37 children <16 years of age with visual impairment (visual acuity worse than 20/70 in the better eye) and one parent for each child were prospectively enrolled. Semistructured individual interviews were performed with children 5-15 years of age (n = 16) and with one parent for each child (ages 0-15 years, N = 37). Interview transcripts were analyzed using NVivo software. Categories of concern were identified from both child and parent interviews, from which broad themes were identified. The frequencies of the themes and specific categories of concerns were calculated. Regarding the child's experience, categories of concern were grouped into 6 themes: visual function (expressed by 13 of 16 children [81%] and 33 of 37 parents [89%]), treatment (63% and 54%), emotions (50% and 68%), social (50% and 70%), physical discomfort (50% and 22%), and worry (38% and 8%). Concerns expressed regarding the parents' own experience were grouped into 5 themes: worry (100%), compensate-adjust for condition (89%), treatment (84%), emotions (81%), and affects family (46%). Individual interviews identified a wide spectrum of concerns in children with visual impairment and their parents, affecting functional, emotional, social and physical domains. Specific concerns will be used to develop patient-derived questionnaires for quantifying the effects of visual impairment on children and parents in everyday life. Copyright © 2017 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

Attentional load and sensory competition in human vision: modulation of fMRI responses by load at fixation during task-irrelevant stimulation in the peripheral visual field.

PubMed

Schwartz, Sophie; Vuilleumier, Patrik; Hutton, Chloe; Maravita, Angelo; Dolan, Raymond J; Driver, Jon

2005-06-01

Perceptual suppression of distractors may depend on both endogenous and exogenous factors, such as attentional load of the current task and sensory competition among simultaneous stimuli, respectively. We used functional magnetic resonance imaging (fMRI) to compare these two types of attentional effects and examine how they may interact in the human brain. We varied the attentional load of a visual monitoring task performed on a rapid stream at central fixation without altering the central stimuli themselves, while measuring the impact on fMRI responses to task-irrelevant peripheral checkerboards presented either unilaterally or bilaterally. Activations in visual cortex for irrelevant peripheral stimulation decreased with increasing attentional load at fixation. This relative decrease was present even in V1, but became larger for successive visual areas through to V4. Decreases in activation for contralateral peripheral checkerboards due to higher central load were more pronounced within retinotopic cortex corresponding to 'inner' peripheral locations relatively near the central targets than for more eccentric 'outer' locations, demonstrating a predominant suppression of nearby surround rather than strict 'tunnel vision' during higher task load at central fixation. Contralateral activations for peripheral stimulation in one hemifield were reduced by competition with concurrent stimulation in the other hemifield only in inferior parietal cortex, not in retinotopic areas of occipital visual cortex. In addition, central attentional load interacted with competition due to bilateral versus unilateral peripheral stimuli specifically in posterior parietal and fusiform regions. These results reveal that task-dependent attentional load, and interhemifield stimulus-competition, can produce distinct influences on the neural responses to peripheral visual stimuli within the human visual system. These distinct mechanisms in selective visual processing may be integrated within posterior parietal areas, rather than earlier occipital cortex.

Visual impairment and the incidence of falls and fractures among older people: longitudinal findings from the Blue Mountains Eye Study.

PubMed

Hong, Thomas; Mitchell, Paul; Burlutsky, George; Samarawickrama, Chameen; Wang, Jie Jin

2014-11-04

We assessed the impact of visual impairment on the incidence of falls and fractures in older persons. Of 3654 baseline participants, 2334, 1952, and 1149 were re-examined after 5, 10, and 15 years. Presenting visual acuity (VA) was measured at each examination. Bilateral and unilateral visual impairment was defined as VA worse than 20/40 in the better and worse eye, respectively. Incident visual impairment was defined in eyes with VA 20/40 or better at baseline, which subsequently developed visual impairment. Incidence of falls was assessed over the 12 months before each visit, whereas incidence of fractures was assessed over the 5 years between two visits. Discrete logistic-regression models with time-dependent variables were used to assess associations between visual impairment and subsequent falls and fractures after adjusting for potential confounding variables. The proportions of participants reporting ≥2 falls ranged between 10% and 14%, and proportions reporting fractures ranged between 12% and 21%, across the three follow-up visits. Participants with incident visual impairment were more likely to report ≥2 falls in 5 years, OR (odds ratio) 1.46, 95% confidence interval (CI) 1.04 to 2.04 (bilateral), and OR 1.22, 95% CI 0.98 to 1.51 (unilateral). Compared to participants with normal vision, those with incident unilateral visual impairment had a higher incidence of fractures over 5 years (OR, 1.27; 95% CI, 0.98-1.51). No increased incidence of falls or fractures was evident after 5+ years among participants with visual impairment. In this older cohort, recent development of visual impairment was associated with increased likelihood of subsequent falls and fractures in the next 5 years, independent of other confounding variables. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Visual and proprioceptive interaction in patients with bilateral vestibular loss☆

PubMed Central

Cutfield, Nicholas J.; Scott, Gregory; Waldman, Adam D.; Sharp, David J.; Bronstein, Adolfo M.

2014-01-01

Following bilateral vestibular loss (BVL) patients gradually adapt to the loss of vestibular input and rely more on other sensory inputs. Here we examine changes in the way proprioceptive and visual inputs interact. We used functional magnetic resonance imaging (fMRI) to investigate visual responses in the context of varying levels of proprioceptive input in 12 BVL subjects and 15 normal controls. A novel metal-free vibrator was developed to allow vibrotactile neck proprioceptive input to be delivered in the MRI system. A high level (100 Hz) and low level (30 Hz) control stimulus was applied over the left splenius capitis; only the high frequency stimulus generates a significant proprioceptive stimulus. The neck stimulus was applied in combination with static and moving (optokinetic) visual stimuli, in a factorial fMRI experimental design. We found that high level neck proprioceptive input had more cortical effect on brain activity in the BVL patients. This included a reduction in visual motion responses during high levels of proprioceptive input and differential activation in the midline cerebellum. In early visual cortical areas, the effect of high proprioceptive input was present for both visual conditions but in lateral visual areas, including V5/MT, the effect was only seen in the context of visual motion stimulation. The finding of a cortical visuo-proprioceptive interaction in BVL patients is consistent with behavioural data indicating that, in BVL patients, neck afferents partly replace vestibular input during the CNS-mediated compensatory process. An fMRI cervico-visual interaction may thus substitute the known visuo-vestibular interaction reported in normal subject fMRI studies. The results provide evidence for a cortical mechanism of adaptation to vestibular failure, in the form of an enhanced proprioceptive influence on visual processing. The results may provide the basis for a cortical mechanism involved in proprioceptive substitution of vestibular function in BVL patients. PMID:25061564

Visual and proprioceptive interaction in patients with bilateral vestibular loss.

PubMed

Cutfield, Nicholas J; Scott, Gregory; Waldman, Adam D; Sharp, David J; Bronstein, Adolfo M

2014-01-01

Following bilateral vestibular loss (BVL) patients gradually adapt to the loss of vestibular input and rely more on other sensory inputs. Here we examine changes in the way proprioceptive and visual inputs interact. We used functional magnetic resonance imaging (fMRI) to investigate visual responses in the context of varying levels of proprioceptive input in 12 BVL subjects and 15 normal controls. A novel metal-free vibrator was developed to allow vibrotactile neck proprioceptive input to be delivered in the MRI system. A high level (100 Hz) and low level (30 Hz) control stimulus was applied over the left splenius capitis; only the high frequency stimulus generates a significant proprioceptive stimulus. The neck stimulus was applied in combination with static and moving (optokinetic) visual stimuli, in a factorial fMRI experimental design. We found that high level neck proprioceptive input had more cortical effect on brain activity in the BVL patients. This included a reduction in visual motion responses during high levels of proprioceptive input and differential activation in the midline cerebellum. In early visual cortical areas, the effect of high proprioceptive input was present for both visual conditions but in lateral visual areas, including V5/MT, the effect was only seen in the context of visual motion stimulation. The finding of a cortical visuo-proprioceptive interaction in BVL patients is consistent with behavioural data indicating that, in BVL patients, neck afferents partly replace vestibular input during the CNS-mediated compensatory process. An fMRI cervico-visual interaction may thus substitute the known visuo-vestibular interaction reported in normal subject fMRI studies. The results provide evidence for a cortical mechanism of adaptation to vestibular failure, in the form of an enhanced proprioceptive influence on visual processing. The results may provide the basis for a cortical mechanism involved in proprioceptive substitution of vestibular function in BVL patients.

The Status of Childhood Blindness and Functional Low Vision in the Eastern Mediterranean Region in 2012

PubMed Central

Khandekar, Rajiv; Kishore, H.; Mansu, Rabiu M.; Awan, Haroon

2014-01-01

Childhood blindness and visual impairment (CBVI) are major disabilities that compromise the normal development of children. Health resources and practices to prevent CBVI are suboptimal in most countries in the Eastern Mediterranean Region (EMR). We reviewed the magnitude and the etiologies of childhood visual disabilities based on the estimates using socioeconomic proxy indicators such as gross domestic product (GDP) per capita and <5-year mortality rates. The result of these findings will facilitate novel concepts in addressing and developing services to effectively reduce CBVI in this region. The current study determined the rates of bilateral blindness (defined as  Best corrected visual acuity(BCVA)) less than 3/60 in the better eye or a visual field of 10° surrounding central fixation) and functional low vision (FLV) (visual impairment for which no treatment or refractive correction can improve the vision up to >6/18 in a better eye) in children <15 years old. We used the 2011 population projections, <5-year mortality rates and GDP per capita of 23 countries (collectively grouped as EMR). Based on the GDP, we divided the countries into three groups; high, middle- and low-income nations. By applying the bilateral blindness and FLV rates to high, middle- and low-income countries from the global literature to the population of children <15 years, we estimated that there could be 238,500 children with bilateral blindness (rate 1.2/1,000) in the region. In addition, there could be approximately 417,725 children with FLV (rate of 2.1/1,000) in the region. The causes of visual disability in the three groups are also discussed based on the available data. As our estimates are based on hospital and blind school studies in the past, they could have serious limitations for projecting the present magnitude and causes of visual disabilities in children of EMR. An effective approach to eye health care and screening for children within primary health care and with the available resources are discussed. The objectives, strategies, and operating procedures for child eye-care are presented. Variables impacting proper screening are discussed. To reach the targets, we recommend urgent implementation of new approaches to low vision and rehabilitation of children. PMID:25371641

The status of childhood blindness and functional low vision in the Eastern Mediterranean region in 2012.

PubMed

Khandekar, Rajiv; Kishore, H; Mansu, Rabiu M; Awan, Haroon

2014-01-01

Childhood blindness and visual impairment (CBVI) are major disabilities that compromise the normal development of children. Health resources and practices to prevent CBVI are suboptimal in most countries in the Eastern Mediterranean Region (EMR). We reviewed the magnitude and the etiologies of childhood visual disabilities based on the estimates using socioeconomic proxy indicators such as gross domestic product (GDP) per capita and <5-year mortality rates. The result of these findings will facilitate novel concepts in addressing and developing services to effectively reduce CBVI in this region. The current study determined the rates of bilateral blindness (defined as  Best corrected visual acuity(BCVA)) less than 3/60 in the better eye or a visual field of 10° surrounding central fixation) and functional low vision (FLV) (visual impairment for which no treatment or refractive correction can improve the vision up to >6/18 in a better eye) in children <15 years old. We used the 2011 population projections, <5-year mortality rates and GDP per capita of 23 countries (collectively grouped as EMR). Based on the GDP, we divided the countries into three groups; high, middle- and low-income nations. By applying the bilateral blindness and FLV rates to high, middle- and low-income countries from the global literature to the population of children <15 years, we estimated that there could be 238,500 children with bilateral blindness (rate 1.2/1,000) in the region. In addition, there could be approximately 417,725 children with FLV (rate of 2.1/1,000) in the region. The causes of visual disability in the three groups are also discussed based on the available data. As our estimates are based on hospital and blind school studies in the past, they could have serious limitations for projecting the present magnitude and causes of visual disabilities in children of EMR. An effective approach to eye health care and screening for children within primary health care and with the available resources are discussed. The objectives, strategies, and operating procedures for child eye-care are presented. Variables impacting proper screening are discussed. To reach the targets, we recommend urgent implementation of new approaches to low vision and rehabilitation of children.

Interhemispheric integration in visual search

PubMed Central

Shipp, Stewart

2011-01-01

The search task of Luck, Hillyard, Mangun and Gazzaniga (1989) was optimised to test for the presence of a bilateral field advantage in the visual search capabilities of normal subjects. The modified design used geometrically regular arrays of 2, 4 or 8 items restricted to hemifields delineated by the vertical or horizontal meridian; the target, if present, appeared at one of two fixed positions per quadrant at an eccentricity of 11 deg. Group and individual performance data were analysed in terms of the slope of response time against display-size functions (‘RT slope’). Averaging performance across all conditions save display mode (bilateral vs. unilateral) revealed a significant bilateral advantage in the form of a 21% increase in apparent item scanning speed for target detection; in the absence of a target, bilateral displays gave a 5% increase in speed that was not significant. Factor analysis by ANOVA confirmed this main effect of display mode, and also revealed several higher order interactions with display geometry, indicating that the bilateral advantage was masked at certain target positions by a crowding-like effect. In a numerical model of search efficiency (i.e. RT slope), bilateral advantage was parameterised by an interhemispheric ‘transfer factor’ (T) that governs the strength of the ipsilateral representation of distractors, and modifies the level of intrahemispheric competition with the target. The factor T was found to be higher in superior field than inferior field; this result held for the modelled data of each individual subject, as well as the group, representing a uniform tendency for the bilateral advantage to be more prominent in inferior field. In fact statistical analysis and modelling of search efficiency showed that the geometrical display factors (target polar and quadrantic location, and associated crowding effects) were all remarkably consistent across subjects. Greater variability was inferred within a fixed, decisional component of response time, with individual subjects capable of opposite hemifield biases. The results are interpretable by a guided search model of spatial attention – a first, parallel stage guiding selection by a second, serial stage – with the proviso that the first stage is relatively insular within each hemisphere. The bilateral advantage in search efficiency can then be attributed to a relative gain in target weight within the initial parallel stage, owing to a reduction in distractor competition mediated specifically by intrahemispheric circuitry. In the absence of a target there is no effective guidance, and hence no basis for a bilateral advantage to enhance search efficiency; the equivalence of scanning speed for the two display modes (bilateral and unilateral) implies a unitary second-stage process mediated via efficient interhemispheric integration. PMID:21640738

Interhemispheric integration in visual search.

PubMed

Shipp, Stewart

2011-07-01

The search task of Luck, Hillyard, Mangun and Gazzaniga (1989) was optimised to test for the presence of a bilateral field advantage in the visual search capabilities of normal subjects. The modified design used geometrically regular arrays of 2, 4 or 8 items restricted to hemifields delineated by the vertical or horizontal meridian; the target, if present, appeared at one of two fixed positions per quadrant at an eccentricity of 11 deg. Group and individual performance data were analysed in terms of the slope of response time against display-size functions ('RT slope'). Averaging performance across all conditions save display mode (bilateral vs. unilateral) revealed a significant bilateral advantage in the form of a 21% increase in apparent item scanning speed for target detection; in the absence of a target, bilateral displays gave a 5% increase in speed that was not significant. Factor analysis by ANOVA confirmed this main effect of display mode, and also revealed several higher order interactions with display geometry, indicating that the bilateral advantage was masked at certain target positions by a crowding-like effect. In a numerical model of search efficiency (i.e. RT slope), bilateral advantage was parameterised by an interhemispheric 'transfer factor' (T) that governs the strength of the ipsilateral representation of distractors, and modifies the level of intrahemispheric competition with the target. The factor T was found to be higher in superior field than inferior field; this result held for the modelled data of each individual subject, as well as the group, representing a uniform tendency for the bilateral advantage to be more prominent in inferior field. In fact statistical analysis and modelling of search efficiency showed that the geometrical display factors (target polar and quadrantic location, and associated crowding effects) were all remarkably consistent across subjects. Greater variability was inferred within a fixed, decisional component of response time, with individual subjects capable of opposite hemifield biases. The results are interpretable by a guided search model of spatial attention - a first, parallel stage guiding selection by a second, serial stage - with the proviso that the first stage is relatively insular within each hemisphere. The bilateral advantage in search efficiency can then be attributed to a relative gain in target weight within the initial parallel stage, owing to a reduction in distractor competition mediated specifically by intrahemispheric circuitry. In the absence of a target there is no effective guidance, and hence no basis for a bilateral advantage to enhance search efficiency; the equivalence of scanning speed for the two display modes (bilateral and unilateral) implies a unitary second-stage process mediated via efficient interhemispheric integration. Copyright © 2011 Elsevier Ltd. All rights reserved.

Working Memory and Speech Recognition in Noise under Ecologically Relevant Listening Conditions: Effects of Visual Cues and Noise Type among Adults with Hearing Loss

ERIC Educational Resources Information Center

Miller, Christi W.; Stewart, Erin K.; Wu, Yu-Hsiang; Bishop, Christopher; Bentler, Ruth A.; Tremblay, Kelly

2017-01-01

Purpose: This study evaluated the relationship between working memory (WM) and speech recognition in noise with different noise types as well as in the presence of visual cues. Method: Seventy-six adults with bilateral, mild to moderately severe sensorineural hearing loss (mean age: 69 years) participated. Using a cross-sectional design, 2…

Early vitrectomy effective for Norrie disease.

PubMed

Walsh, Mark K; Drenser, Kimberly A; Capone, Antonio; Trese, Michael T

2010-04-01

To review our experience with Norrie disease to determine if early vitrectomy abrogates the natural history of this rare disease; namely, bilateral no light perception visual acuity and phthisis bulbi. We retrospectively reviewed the medical records of all patients seen in our tertiary care pediatric retinal clinical practice from 1988 through 2008 with a potential diagnosis of Norrie disease. Inclusion required not only clinical findings consistent with Norrie disease but also genetics and/or a family history consistent with Norrie disease. Medical record review revealed 14 boys with clinically diagnosed Norrie disease and either Norrie disease gene (NDP) mutations noted on genetic testing (13 patients) and/or a clear family history consistent with Norrie disease (4 patients). All 14 boys with definite Norrie disease had vitrectomy with or without lensectomy in at least 1 eye prior to 12 months of age. Of the 14 boys with definite Norrie disease, 7 maintained at least light perception visual acuity in 1 eye and 3 had no light perception visual acuity bilaterally; visual acuity data were not available for 4 patients. Only 2 of 24 (8%) eyes became phthisical. Historically, no treatment has been offered to mitigate the dismal natural history of Norrie disease. We recommend consideration of early vitrectomy in Norrie disease.

Functional lateralization of temporoparietal junction - imitation inhibition, visual perspective-taking and theory of mind.

PubMed

Santiesteban, Idalmis; Banissy, Michael J; Catmur, Caroline; Bird, Geoffrey

2015-10-01

Although neuroimaging studies have consistently identified the temporoparietal junction (TPJ) as a key brain region involved in social cognition, the literature is far from consistent with respect to lateralization of function. For example, during theory-of-mind tasks bilateral TPJ activation is found in some studies but only right hemisphere activation in others. Visual perspective-taking and imitation inhibition, which have been argued to recruit the same socio-cognitive processes as theory of mind, are associated with unilateral activation of either left TPJ (perspective taking) or right TPJ (imitation inhibition). The present study investigated the functional lateralization of TPJ involvement in the above three socio-cognitive abilities using transcranial direct current stimulation. Three groups of healthy adults received anodal stimulation over right TPJ, left TPJ or the occipital cortex prior to performing three tasks (imitation inhibition, visual perspective-taking and theory of mind). In contrast to the extant neuroimaging literature, our results suggest bilateral TPJ involvement in imitation inhibition and visual perspective-taking, while no effect of anodal stimulation was observed on theory of mind. The discrepancy between these findings and those obtained using neuroimaging highlight the efficacy of neurostimulation as a complementary methodological tool in cognitive neuroscience. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Suppression of Melatonin Secretion in Totally Visually Blind People by Ocular Exposure to White Light: Clinical Characteristics.

PubMed

Hull, Joseph T; Czeisler, Charles A; Lockley, Steven W

2018-04-03

Although most totally visually blind individuals exhibit nonentrained circadian rhythms due to an inability of light to entrain the circadian pacemaker, a small proportion retain photic circadian entrainment, melatonin suppression, and other nonimage-forming responses to light. It is thought that these responses to light persist because of the survival of melanospin-containing intrinsically photosensitive retinal ganglion cells (ipRGCs), which project primarily to the circadian pacemaker and are functionally distinct from the rod and cone photoreceptors that mediate vision. We aimed to assess the integrity of nonimage-forming photoreception in totally visually blind patients with a range of ocular disorders. Within-subject, dark-controlled design. A total of 18 totally visually blind individuals (7 females; mean age ± standard deviation = 49.8±11.0 years) with various causes of blindness, including 3 bilaterally enucleated controls. Melatonin concentrations were compared during exposure to a 6.5-hour bright white light (∼7000 lux) with melatonin concentrations measured 24 hours earlier at the corresponding clock times under dim-light (4 lux) conditions. Area under the curve (AUC) for melatonin concentration. Melatonin concentrations were significantly suppressed (defined as ≥33% suppression) during the bright-light condition compared with the dim-light condition in 5 of 15 participants with eyes (retinitis pigmentosa, n = 2; retinopathy of prematurity [ROP], n = 2; bilateral retinal detachments, n = 1). Melatonin concentrations remained unchanged in response to light in the remaining 10 participants with eyes (ROP, n = 3; optic neuritis/neuropathy, n = 2; retinopathy unknown, n = 2; congenital glaucoma, n = 1; congenital rubella syndrome, n = 1; measles retinopathy, n = 1) and in all 3 bilaterally enucleated participants. These data confirm that light-induced suppression of melatonin remains functionally intact in a minority of totally visually blind individuals with eyes. None of the bilaterally enucleated individuals or those with phthisis bulbi was responsive to light; of the remainder, half were responsive to light. Although inner retinal damage is associated with a high likelihood that nonimage-forming photoreception is absent, the impact of outer retinal damage is more ambiguous, and therefore the assessment of the presence, attenuation, or absence of nonimage-forming light responses in totally blind patients requires careful individual confirmation and cannot simply be assumed from the type of blindness. Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

CASE REPORT OF SEVERE PROLIFERATIVE RETINOPATHY IN A PATIENT WITH CONGENITAL LIPODYSTROPHY.

PubMed

Rosin, Boris; Jaouni, Tareq

2017-08-21

A case report of a patient with severe proliferative retinopathy due to congenital lipodystrophy. We reviewed the medical history, imaging, and surgical procedures of a 25-year-old woman with a history of congenital lipodystrophy, presenting with bilateral combined tractional and exudative retinal detachment, poorly controlled diabetes mellitus, and extreme dislipidemia. The patient underwent retinal detachment repair surgery both eyes. On the last follow-up, both retinae were flat, and visual acuity had improved in the right eye to J3 for near and finger counting 3 m for distance. Surgery combining pars plana vitrectomy and scleral bucking successfully flattened both retinae and significantly improved visual acuity in one eye in this case of bilateral retinal detachment with combined tractional and exudative components in a patient with congenital lipodystrophy. Surgical control of retinal complications is thus possible, provided there is adequate control of the underlying risk factors.

Quality of life assessment in ocular toxoplasmosis in a Colombian population.

PubMed

de-la-Torre, Alejandra; González-López, Gilberto; Montoya-Gutiérrez, Johanna Milena; Marín-Arango, Viviana; Gómez-Marín, Jorge Enrique

2011-08-01

To assess the quality of life in patients with ocular toxoplasmosis. The participants were 29 otherwise healthy patients with retinochoroidal lesions consistent with Toxoplasma infection. The controls were 29 gender and age-matched people with normal visual function who came from the same socioeconomic and educational background as the participants. The authors used the version of the National Eye Institute 25-item visual function questionnaire (NEI VFQ25). Patients with ocular toxoplasmosis had statistically significant lower scores than controls for all the subscales, except for color vision. Patients with bilateral lesions were more affected in the mental health, difficulties role, and specific vision subscales. The median of the compound score for the participants was 79 (range 35-99) and for the controls was 95 (range 72-98). People with ocular toxoplasmosis have worse vision-related quality of life than people without the condition, especially if they have bilateral lesions and more recurrences.

Bilateral foveal retinoschisis accompanying unilateral peripheral retinoschisis

PubMed Central

Kocak, Nilufer; Ozturk, Taylan A; Kaynak, Suleyman

2014-01-01

X-linked juvenile retinoschisis is a rare hereditary retinal disease characterized by a tangential splitting of the neurosensory retina which may cause early-onset visual impairment. Existence of the retinal neurosensory layer splitting on cross-sectional images of optical coherance tomography (OCT) and the absence of leakage on fluorescein angiography (FA) help confirming the diagnosis. Such diagnostic tests are also helpful in determining the management of the disease. However, most of the retinoschisis cavities remain stable and rarely extend to the posterior pole, many authors suggest laser prophylaxis to avoid the potential risk of retinal detachment due to holes in the outer retinal layer. Herein, we report a case with bilateral foveal retinoschisis accompanying unilateral peripheral retinoschisis who was evaluated with detailed ophthalmologic examination. Visual acuity, fundoscopy, OCT, and FA remained stable in the second year of follow-up after prophylactic argon laser treatment. PMID:23571248

Cometa Hyakutake (C/1996 B2): análise do gás e características físicas das partículas de poeira

NASA Astrophysics Data System (ADS)

Sanzovo, G. C.; de Almeida, A. A.; Boczko, R.

2003-08-01

A completa caracterização e compreensão do núcleo de um cometa novo é de fundamental importância para a elucidação dos processos físicos e químicos atuantes na época da formação do Sistema Solar. O Cometa Hyakutake, conjuntamente com o Cometa Hale-Bopp representam os objetos mais brilhantes que visitaram o Sistema Solar Interno nos últimos 20 anos. Neste Trabalho, nós aplicamos o Método Semi-Empírico das Magnitudes Visuais (MSEMV) à aproximadamente 4000 dados observacionais que correlacionam a magnitude visual absoluta com a distância heliocêntrica para o Cometa Hyakutake nas fases pré- e pós-periélicas. Como produto da aplicação desse método, conseguimos caracterizar dimensionalmente seu núcleo e área ativa efetiva. As taxas de produção dos radicais CN, C2 e C3, obtidos a partir de dados disponíveis na literatura, revelam que, além de muito brilhante, o Hyakutake é um cometa "normal" no sentido de Cochran (1986). Desse modo, deduzimos as taxas de perdas de água (em moléculas/s) a partir da análise de sua magnitude visual aparente, e as convertemos em taxas de perdas de gás (em g/s), despreendido pelo nucleo cometário. Com o auxílio do modelo fotométrico clássico da poeira, realizamos uma análise sistemática e uniforme dessa componente cometária, a partir dos fluxos observacionais no contínuo, para os comprimentos de onda 365,0 e 484,5 nm, assumindo que esses fluxos são o resultado da radiação solar espalhada por grãos de partículas micrométricos presentes na coma. Com isso, pudemos obter as taxas de produção (em g/s), cores (relativas à cor neutra solar), e as dimensões efetivas médias das partículas de poeira, bem como as razões poeira-gás.

Orphan disease: Cherubism, optic atrophy, and short stature.

PubMed

Jeevanandham, Balaji; Ramachandran, Rajoo; Dhanapal, Vignesh; Subramanian, Ilanchezhian; Sai, Venkata

2018-01-01

A 12-year-old female presented with complaints of progressive visual impairment in both her eyes. On clinical examination, she was short for her age and her ophthalmoscopic examination revealed bilateral optic atrophy. Computed tomography of the patient revealed multiple expansile lytic lesions of mandible suggesting cherubism. The optic atrophy was confirmed on magnetic resonance imaging, which additionally revealed bilateral retrocerebellar arachnoid cysts. This association of cherubism with optic atrophy and short stature was grouped as orphan disease by National Institutes of Health and only one case was reported in the literature so far.

Amblyopia treatment strategies and new drug therapies.

PubMed

Pescosolido, Nicola; Stefanucci, Alessio; Buomprisco, Giuseppe; Fazio, Stefano

2014-01-01

Amblyopia is a unilateral or bilateral reduction of visual acuity secondary to abnormal visual experience during early childhood. It is one of the most common causes of vision loss and monocular blindness and is commonly associated with strabismus, anisometropia, and visual deprivation (in particular congenital cataract and ptosis). It is clinically defined as a two-line difference of best-corrected visual acuity between the eyes. The purpose of this study was to understand the neural mechanisms of amblyopia and summarize the current therapeutic strategies. In particular, the authors focused on the concept of brain plasticity and its implication for new treatment strategies for children and adults with amblyopia. Copyright 2014, SLACK Incorporated.

Endogenous Nocardial Endophthalmitis in an Immunosuppressed Patient: A Serious Warning of an Underlying Life Threatening and Blinding Disorder.

PubMed

Trehan, Hemant; Kaushik, Jaya; Jain, Vaibhav Kumar; Parihar, Jitendra Kumar Singh; Avasthi, Abhijit

2017-01-01

To report a case of bilateral endogenous nocardial endophthalmitis with central nervous system involvement in an immunocompromised individual with an extremely poor outcome. A 35-year-old man with a history of long-term, prescribed oral steroid use for membranoproliferative glomerulonephritis presented with profound bilateral vision loss. Patient's diagnosis of bilateral endogenous nocardial endophthalmitis was delayed. Nocardia was finally isolated from a brain biopsy after a repeat magnetic resonance imaging revealed a brain abscess. With anti-nocardia therapy, patient improved systemically, but the visual outcome was poor, with no light perception in both eyes. Ocular nocardiosis is a serious vision and life threatening disorder, particularly in patients on immunosuppressive therapy. A high index of suspicion is required for successful treatment.

Bilateral Mycobacterium chelonae Keratitis after Phacoemulsification Cataract Surgery.

PubMed

Martinez, Jaime D; Amescua, Guillermo; Lozano-Cárdenas, Jesus; Suh, Leejee H

2017-01-01

The purpose of this manuscript is to report the case of an 81-year-old patient who presented with bilateral keratitis after phacoemulsification surgery. Cultures came back positive for Mycobacterium chelonae . Despite aggressive topical and systemic antimicrobial treatment, the patient developed a corneal perforation in both eyes, treated with corneal glue in the right eye and corneoscleral patch in the left eye. After two years of follow-up, patient was free of infection in the right eye with visual acuity of 20/200 and the left eye progressed to phthisis bulbi. We present an unusual case of bilateral Mycobacterium chelonae keratitis associated with phacoemulsification cataract surgery. This case represents the importance of making clinicians aware of this devastating infection and highlights the need for better management to improve outcomes.

[Bilateral non-arteritic ischemic optic neuropathy during treatment of viral hepatitis C with pegylated interferon and Ribavirin].

PubMed

Iferkhass, S; Elasri, F; Chatioui, S; Khoyaali, A; Bargach, T; Reda, K; Oubaaz, A

2015-01-01

Hepatitis C is a serious viral infection, for which the current treatment is based on the combination of pegylated interferon (IFN) and Ribavirin(®). Ophthalmic complications observed with PEG-IFN are infrequent and of variable prognosis. They often include an ischemic retinopathy with typical cotton-wool spots, hemorrhage and retinal edema, and rarely acute non-arteritic anterior ischemic optic neuropathy as illustrated by our report. We report the case of a 51-year-old man followed for chronic active hepatitis C, who presented in the fourth month of treatment with pegylated interferon and vidarabine with a sharp decline in visual acuity secondary to acute bilateral non-arteritic anterior ischemic optic neuropathy. The hepatitis C treatment was discontinued. His course was notable by the third week for a significant regression of papilledema with improvement in visual acuity in the right eye and no change in the left eye, remaining at counting fingers. After regressing for four years, the disease progressed to bilateral temporal optic atrophy without change in visual acuity. Pegylated interferon and Ribavirin(®) are commonly used in the treatment of chronic hepatitis C. They are the source of various ophthalmologic complications of varied severity. The pathophysiology of this ocular toxicity currently remains hypothetical. Non-arteritic ischemic optic neuropathy is still a relatively rare complication with a poor functional prognosis, often requiring discontinuation of treatment. Thus, careful ophthalmologic monitoring before and during antiviral treatment of patients with hepatitis C appears necessary. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Cross-Hemispheric Collaboration and Segregation Associated with Task Difficulty as Revealed by Structural and Functional Connectivity

PubMed Central

Cabeza, Roberto

2015-01-01

Although it is known that brain regions in one hemisphere may interact very closely with their corresponding contralateral regions (collaboration) or operate relatively independent of them (segregation), the specific brain regions (where) and conditions (how) associated with collaboration or segregation are largely unknown. We investigated these issues using a split field-matching task in which participants matched the meaning of words or the visual features of faces presented to the same (unilateral) or to different (bilateral) visual fields. Matching difficulty was manipulated by varying the semantic similarity of words or the visual similarity of faces. We assessed the white matter using the fractional anisotropy (FA) measure provided by diffusion tensor imaging (DTI) and cross-hemispheric communication in terms of fMRI-based connectivity between homotopic pairs of cortical regions. For both perceptual and semantic matching, bilateral trials became faster than unilateral trials as difficulty increased (bilateral processing advantage, BPA). The study yielded three novel findings. First, whereas FA in anterior corpus callosum (genu) correlated with word-matching BPA, FA in posterior corpus callosum (splenium-occipital) correlated with face-matching BPA. Second, as matching difficulty intensified, cross-hemispheric functional connectivity (CFC) increased in domain-general frontopolar cortex (for both word and face matching) but decreased in domain-specific ventral temporal lobe regions (temporal pole for word matching and fusiform gyrus for face matching). Last, a mediation analysis linking DTI and fMRI data showed that CFC mediated the effect of callosal FA on BPA. These findings clarify the mechanisms by which the hemispheres interact to perform complex cognitive tasks. PMID:26019335

Glaucoma and disability: which tasks are affected, and at what stage of disease?

PubMed

Ramulu, Pradeep

2009-03-01

To summarize recent work from clinical and epidemiological studies that describe how, and at what stage, glaucoma affects the performance of important vision-related activities. Difficulties with the extremes of lighting are the most frequent complaint in glaucoma. Individuals with bilateral glaucoma also self-report difficulty with a broad array of tasks, including reading, walking, and driving. Bilateral glaucoma is associated with driving cessation and limitation, bumping into objects, slower walking, and falls. Some, but not all, studies also demonstrate higher accident rates in glaucoma. Measurable effects on reading speed have only been observed with field damage severe enough to affect binocular central acuity. Glaucoma with bilateral visual field loss is associated with increased symptoms and a measurable decline in mobility and driving. Further work is necessary to establish whether unilateral glaucoma has a significant impact on patients, to determine whether reading difficulty is common in patients with bilateral glaucoma, and to establish the effects of lighting conditions on task performance in glaucoma.

Characteristics of bilateral hand function in individuals with unilateral dystonia due to perinatal stroke: sensory and motor aspects.

PubMed

de Campos, Ana Carolina; Kukke, Sahana N; Hallett, Mark; Alter, Katharine E; Damiano, Diane L

2014-05-01

The authors assessed bilateral motor and sensory function in individuals with upper limb dystonia due to unilateral perinatal stroke and explored interrelationships of motor function and sensory ability. Reach kinematics and tactile sensation were measured in 7 participants with dystonia and 9 healthy volunteers. The dystonia group had poorer motor (hold time, reach time, shoulder/elbow correlation) and sensory (spatial discrimination, stereognosis) outcomes than the control group on the nondominant side. On the dominant side, only sensation (spatial discrimination, stereognosis) was poorer in the dystonia group compared with the control group. In the dystonia group, although sensory and motor outcomes were uncorrelated, dystonia severity was related to poorer stereognosis, longer hold and reach times, and decreased shoulder/elbow coordination. Findings of bilateral sensory deficits in dystonia can be explained by neural reorganization. Visual compensation for somatosensory changes in the nonstroke hemisphere may explain the lack of bilateral impairments in reaching.

Characteristics of bilateral hand function in individuals with unilateral dystonia due to perinatal stroke: sensory and motor aspects

PubMed Central

de Campos, Ana Carolina; Kukke, Sahana N.; Hallett, Mark; Alter, Katharine E.; Damiano, Diane L.

2014-01-01

We assessed bilateral motor and sensory function in individuals with upper limb dystonia due to unilateral perinatal stroke and explored interrelationships of motor function and sensory ability. Reach kinematics and tactile sensation were measured in seven participants with dystonia and nine healthy volunteers. The dystonia group had poorer motor (hold time, reach time, shoulder/elbow correlation) and sensory (spatial discrimination, stereognosis) outcomes than the control group on the non-dominant side. On the dominant side, only sensation (spatial discrimination, stereognosis) was poorer in the dystonia group compared to the control group. In the dystonia group, although sensory and motor outcomes were uncorrelated, dystonia severity was related to poorer stereognosis, longer hold and reach times, and decreased shoulder/elbow coordination. Findings of bilateral sensory deficits in dystonia may be explained by neural reorganization. Visual compensation for somatosensory changes in the non-stroke hemisphere may explain the lack of bilateral impairments in reaching. PMID:24396131

Simulated astigmatism impairs academic-related performance in children.

PubMed

Narayanasamy, Sumithira; Vincent, Stephen J; Sampson, Geoff P; Wood, Joanne M

2015-01-01

Astigmatism is an important refractive condition in children. However, the functional impact of uncorrected astigmatism in this population is not well established, particularly with regard to academic performance. This study investigated the impact of simulated bilateral astigmatism on academic-related tasks before and after sustained near work in children. Twenty visually normal children (mean age: 10.8 ± 0.7 years; six males and 14 females) completed a range of standardised academic-related tests with and without 1.50 D of simulated bilateral astigmatism (with both academic-related tests and the visual condition administered in a randomised order). The simulated astigmatism was induced using a positive cylindrical lens while maintaining a plano spherical equivalent. Performance was assessed before and after 20 min of sustained near work, during two separate testing sessions. Academic-related measures included a standardised reading test (the Neale Analysis of Reading Ability), visual information processing tests (Coding and Symbol Search subtests from the Wechsler Intelligence Scale for Children) and a reading-related eye movement test (the Developmental Eye Movement test). Each participant was systematically assigned either with-the-rule (WTR, axis 180°) or against-the-rule (ATR, axis 90°) simulated astigmatism to evaluate the influence of axis orientation on any decrements in performance. Reading, visual information processing and reading-related eye movement performance were all significantly impaired by both simulated bilateral astigmatism (p < 0.001) and sustained near work (p < 0.001), however, there was no significant interaction between these factors (p > 0.05). Simulated astigmatism led to a reduction of between 5% and 12% in performance across the academic-related outcome measures, but there was no significant effect of the axis (WTR or ATR) of astigmatism (p > 0.05). Simulated bilateral astigmatism impaired children's performance on a range of academic-related outcome measures irrespective of the orientation of the astigmatism. These findings have implications for the clinical management of non-amblyogenic levels of astigmatism in relation to academic performance in children. Correction of low to moderate levels of astigmatism may improve the functional performance of children in the classroom. © 2014 The Authors Ophthalmic & Physiological Optics © 2014 The College of Optometrists.

Visual Agnosia and Posterior Cerebral Artery Infarcts: An Anatomical-Clinical Study

PubMed Central

Martinaud, Olivier; Pouliquen, Dorothée; Gérardin, Emmanuel; Loubeyre, Maud; Hirsbein, David; Hannequin, Didier; Cohen, Laurent

2012-01-01

Background To evaluate systematically the cognitive deficits following posterior cerebral artery (PCA) strokes, especially agnosic visual disorders, and to study anatomical-clinical correlations. Methods and Findings We investigated 31 patients at the chronic stage (mean duration of 29.1 months post infarct) with standardized cognitive tests. New experimental tests were used to assess visual impairments for words, faces, houses, and objects. Forty-one healthy subjects participated as controls. Brain lesions were normalized, combined, and related to occipitotemporal areas responsive to specific visual categories, including words (VWFA), faces (FFA and OFA), houses (PPA) and common objects (LOC). Lesions were located in the left hemisphere in 15 patients, in the right in 13, and bilaterally in 3. Visual field defects were found in 23 patients. Twenty patients had a visual disorder in at least one of the experimental tests (9 with faces, 10 with houses, 7 with phones, 3 with words). Six patients had a deficit just for a single category of stimulus. The regions of maximum overlap of brain lesions associated with a deficit for a given category of stimuli were contiguous to the peaks of the corresponding functional areas as identified in normal subjects. However, the strength of anatomical-clinical correlations was greater for words than for faces or houses, probably due to the stronger lateralization of the VWFA, as compared to the FFA or the PPA. Conclusions Agnosic visual disorders following PCA infarcts are more frequent than previously reported. Dedicated batteries of tests, such as those developed here, are required to identify such deficits, which may escape clinical notice. The spatial relationships of lesions and of regions activated in normal subjects predict the nature of the deficits, although individual variability and bilaterally represented systems may blur those correlations. PMID:22276198

Visual agnosia and posterior cerebral artery infarcts: an anatomical-clinical study.

PubMed

Martinaud, Olivier; Pouliquen, Dorothée; Gérardin, Emmanuel; Loubeyre, Maud; Hirsbein, David; Hannequin, Didier; Cohen, Laurent

2012-01-01

To evaluate systematically the cognitive deficits following posterior cerebral artery (PCA) strokes, especially agnosic visual disorders, and to study anatomical-clinical correlations. We investigated 31 patients at the chronic stage (mean duration of 29.1 months post infarct) with standardized cognitive tests. New experimental tests were used to assess visual impairments for words, faces, houses, and objects. Forty-one healthy subjects participated as controls. Brain lesions were normalized, combined, and related to occipitotemporal areas responsive to specific visual categories, including words (VWFA), faces (FFA and OFA), houses (PPA) and common objects (LOC). Lesions were located in the left hemisphere in 15 patients, in the right in 13, and bilaterally in 3. Visual field defects were found in 23 patients. Twenty patients had a visual disorder in at least one of the experimental tests (9 with faces, 10 with houses, 7 with phones, 3 with words). Six patients had a deficit just for a single category of stimulus. The regions of maximum overlap of brain lesions associated with a deficit for a given category of stimuli were contiguous to the peaks of the corresponding functional areas as identified in normal subjects. However, the strength of anatomical-clinical correlations was greater for words than for faces or houses, probably due to the stronger lateralization of the VWFA, as compared to the FFA or the PPA. Agnosic visual disorders following PCA infarcts are more frequent than previously reported. Dedicated batteries of tests, such as those developed here, are required to identify such deficits, which may escape clinical notice. The spatial relationships of lesions and of regions activated in normal subjects predict the nature of the deficits, although individual variability and bilaterally represented systems may blur those correlations.

Clinical Evaluation of Functional Vision of +1.5 Diopters near Addition, Aspheric, Rotational Asymmetric Multifocal Intraocular Lens

PubMed Central

Khoramnia, Rahmin; Attia, Mary Safwat; Koss, Michael Janusz; Linz, Katharina; Auffarth, Gerd Uwe

2016-01-01

Purpose To evaluate postoperative outcomes and visual performance in intermediate distance after implantation of a +1.5 diopters (D) addition, aspheric, rotational asymmetric multifocal intraocular lens (MIOL). Methods Patients underwent bilateral cataract surgery with implantation of an aspheric, asymmetric MIOL with +1.5 D near addition. A complete ophthalmological examination was performed preoperatively and 3 months postoperatively. The main outcome measures were monocular and binocular uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected intermediate visual acuity (UIVA), distance corrected intermediate visual acuity (DCIVA), uncorrected near visual acuity (UNVA) and distance corrected keratometry, and manifest refraction. The Salzburg Reading Desk was used to analyze unilateral and bilateral functional vision with uncorrected and corrected reading acuity, reading distance, reading speed, and the smallest log-scaled print size that could be read effectively at near and intermediate distances. Results The study comprised 60 eyes of 30 patients (mean age, 68.30 ± 9.26 years; range, 34 to 80 years). There was significant improvement in UDVA and CDVA. Mean UIVA was 0.01 ± 0.09 logarithm of the minimum angle of resolution (logMAR) and mean DCIVA was -0.02 ± 0.11 logMAR. In Salzburg Reading Desk analysis for UIVA, the mean subjective intermediate distance was 67.58 ± 8.59 cm with mean UIVA of -0.02 ± 0.09 logMAR and mean word count of 96.38 ± 28.32 words/min. Conclusions The new aspheric, asymmetric, +1.5 D near addition MIOL offers good results for distance visual function in combination with good performance for intermediate distances and functional results for near distance. PMID:27729759

Clinical Evaluation of Functional Vision of +1.5 Diopters near Addition, Aspheric, Rotational Asymmetric Multifocal Intraocular Lens.

PubMed

Kretz, Florian Tobias Alwin; Khoramnia, Rahmin; Attia, Mary Safwat; Koss, Michael Janusz; Linz, Katharina; Auffarth, Gerd Uwe

2016-10-01

To evaluate postoperative outcomes and visual performance in intermediate distance after implantation of a +1.5 diopters (D) addition, aspheric, rotational asymmetric multifocal intraocular lens (MIOL). Patients underwent bilateral cataract surgery with implantation of an aspheric, asymmetric MIOL with +1.5 D near addition. A complete ophthalmological examination was performed preoperatively and 3 months postoperatively. The main outcome measures were monocular and binocular uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected intermediate visual acuity (UIVA), distance corrected intermediate visual acuity (DCIVA), uncorrected near visual acuity (UNVA) and distance corrected keratometry, and manifest refraction. The Salzburg Reading Desk was used to analyze unilateral and bilateral functional vision with uncorrected and corrected reading acuity, reading distance, reading speed, and the smallest log-scaled print size that could be read effectively at near and intermediate distances. The study comprised 60 eyes of 30 patients (mean age, 68.30 ± 9.26 years; range, 34 to 80 years). There was significant improvement in UDVA and CDVA. Mean UIVA was 0.01 ± 0.09 logarithm of the minimum angle of resolution (logMAR) and mean DCIVA was -0.02 ± 0.11 logMAR. In Salzburg Reading Desk analysis for UIVA, the mean subjective intermediate distance was 67.58 ± 8.59 cm with mean UIVA of -0.02 ± 0.09 logMAR and mean word count of 96.38 ± 28.32 words/min. The new aspheric, asymmetric, +1.5 D near addition MIOL offers good results for distance visual function in combination with good performance for intermediate distances and functional results for near distance.

Comparative analysis of visual outcomes with 4 intraocular lenses: Monofocal, multifocal, and extended range of vision.

PubMed

Pedrotti, Emilio; Carones, Francesco; Aiello, Francesco; Mastropasqua, Rodolfo; Bruni, Enrico; Bonacci, Erika; Talli, Pietro; Nucci, Carlo; Mariotti, Cesare; Marchini, Giorgio

2018-02-01

To compare the visual acuity, refractive outcomes, and quality of vision in patients with bilateral implantation of 4 intraocular lenses (IOLs). Department of Neurosciences, Biomedicine and Movement Sciences, Eye Clinic, University of Verona, Verona, and Carones Ophthalmology Center, Milano, Italy. Prospective case series. The study included patients who had bilateral cataract surgery with the implantation of 1 of 4 IOLs as follows: Tecnis 1-piece monofocal (monofocal IOL), Tecnis Symfony extended range of vision (extended-range-of-vision IOL), Restor +2.5 diopter (D) (+2.5 D multifocal IOL), and Restor +3.0 D (+3.0 D multifocal IOL). Visual acuity, refractive outcome, defocus curve, objective optical quality, contrast sensitivity, spectacle independence, and glare perception were evaluated 6 months after surgery. The study comprised 185 patients. The extended-range-of-vision IOL (55 patients) showed better distance visual outcomes than the monofocal IOL (30 patients) and high-addition apodized diffractive-refractive multifocal IOLs (P ≤ .002). The +3.0 D multifocal IOL (50 patients) showed the best near visual outcomes (P < .001). The +2.5 D multifocal IOL (50 patients) and extended-range-of-vision IOL provided significantly better intermediate visual outcomes than the other 2 IOLs, with significantly better vision for a defocus level of -1.5 D (P < .001). Better spectacle independence was shown for the +2.5 D multifocal IOL and extended-range-of-vision IOL (P < .001). The extended-range-of-vision IOL and +2.5 D multifocal IOL provided significantly better intermediate visual restoration after cataract surgery than the monofocal IOL and +3.0 D multifocal IOL, with significantly better quality of vision with the extended-range-of-vision IOL. Copyright © 2018 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Anatomical Substrates of Visual and Auditory Miniature Second-language Learning

PubMed Central

Newman-Norlund, Roger D.; Frey, Scott H.; Petitto, Laura-Ann; Grafton, Scott T.

2007-01-01

Longitudinal changes in brain activity during second language (L2) acquisition of a miniature finite-state grammar, named Wernickese, were identified with functional magnetic resonance imaging (fMRI). Participants learned either a visual sign language form or an auditory-verbal form to equivalent proficiency levels. Brain activity during sentence comprehension while hearing/viewing stimuli was assessed at low, medium, and high levels of proficiency in three separate fMRI sessions. Activation in the left inferior frontal gyrus (Broca’s area) correlated positively with improving L2 proficiency, whereas activity in the right-hemisphere (RH) homologue was negatively correlated for both auditory and visual forms of the language. Activity in sequence learning areas including the premotor cortex and putamen also correlated with L2 proficiency. Modality-specific differences in the blood oxygenation level-dependent signal accompanying L2 acquisition were localized to the planum temporale (PT). Participants learning the auditory form exhibited decreasing reliance on bilateral PT sites across sessions. In the visual form, bilateral PT sites increased in activity between Session 1 and Session 2, then decreased in left PT activity from Session 2 to Session 3. Comparison of L2 laterality (as compared to L1 laterality) in auditory and visual groups failed to demonstrate greater RH lateralization for the visual versus auditory L2. These data establish a common role for Broca’s area in language acquisition irrespective of the perceptual form of the language and suggest that L2s are processed similar to first languages even when learned after the ‘‘critical period.’’ The right frontal cortex was not preferentially recruited by visual language after accounting for phonetic/structural complexity and performance. PMID:17129186

Impact of colour in the assessment of potential visual acuity in patients with age-related macular degeneration.

PubMed

Dorrepaal, Stephen J; Markowitz, Samuel N

2013-06-01

To compare chromatic and achromatic potential visual acuity (PVA) in patients with bilateral low vision caused by age-related macular degeneration (AMD). Prospective, nonrandomized, observational case series. Fifty-five patients, representing a consecutive series of patients all presenting with bilateral AMD. Best-corrected visual acuity of each eye was measured using an Early Treatment in Diabetic Retinopathy Study (ETDRS) chart with appropriate near correction. Included were cases with visual acuity of 0.4 logMAR (20/50) or worse in both eyes. Achromatic and chromatic PVA were measured in each eye using white on black and red on yellow flooding E charts at 50 cm in controlled lighting conditions. One hundred and seven eyes from 55 patients were included in the analysis. Mean achromatic and chromatic PVA were 0.69 ± 0.26 and 0.65 ± 0.22 logMAR, respectively. Overall, patients had a significantly higher chromatic than achromatic PVA, with a median difference of 0.1 logMAR (p<0.05). Patients with ETDRS visual acuity worse than 0.9 logMAR also had a significantly higher chromatic than achromatic PVA, with a median difference of 0.1 logMAR (p<0.05). Patients with ETDRS visual acuity between 0.4 and 0.9 logMAR had a trend toward a higher chromatic than achromatic visual acuity that was not significant, with a median difference of 0.1 logMAR (p = 0.8539). Patients with low vision caused by AMD can discern smaller targets when a red on yellow colour scheme is used than when using achromatic white on black charts. Copyright © 2013 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

Nervus terminalis innervation of the goldfish retina and behavioral visual sensitivity.

PubMed

Davis, R E; Kyle, A; Klinger, P D

1988-08-31

The possibility that axon terminals of the nervus terminalis in the goldfish retina regulate visual sensitivity was examined psychophysically. Fish were classically conditioned to respond in darkness to a diffuse red light conditioned stimulus. Bilateral ablation of the olfactory bulb and telencephalon had no significant effect on response threshold which was measured by a staircase method. Retinopetal nervus terminalis fibres thus appear to play no role in maintaining scotopic photosensitivity.

The temporal evolution of electromagnetic markers sensitive to the capacity limits of visual short-term memory.

PubMed

Mitchell, Daniel J; Cusack, Rhodri

2011-01-01

An electroencephalographic (EEG) marker of the limited contents of human visual short-term memory (VSTM) has previously been described. Termed contralateral delay activity, this consists of a sustained, posterior, negative potential that correlates with memory load and is greatest contralateral to the remembered hemifield. The current investigation replicates this finding and uses magnetoencephalography (MEG) to characterize its magnetic counterparts and their neural generators as they evolve throughout the memory delay. A parametric manipulation of memory load, within and beyond capacity limits, allows separation of signals that asymptote with behavioral VSTM performance from additional responses that contribute to a linear increase with set-size. Both EEG and MEG yielded bilateral signals that track the number of objects held in memory, and contralateral signals that are independent of memory load. In MEG, unlike EEG, the contralateral interaction between hemisphere and item load is much weaker, suggesting that bilateral and contralateral markers of memory load reflect distinct sources to which EEG and MEG are differentially sensitive. Nonetheless, source estimation allowed both the bilateral and the weaker contralateral capacity-limited responses to be localized, along with a load-independent contralateral signal. Sources of global and hemisphere-specific signals all localized to the posterior intraparietal sulcus during the early delay. However the bilateral load response peaked earlier and its generators shifted later in the delay. Therefore the hemifield-specific response may be more closely tied to memory maintenance while the global load response may be involved in initial processing of a limited number of attended objects, such as their individuation or consolidation into memory.

[Air bags and eye injuries: chemical burns and major traumatic ocular lesions--a case study].

PubMed

Bendeddouche, K; Assaf, E; Emadisson, H; Forestier, F; Salvanet-Bouccara, A

2003-10-01

The authors report a case of bilateral eye lesions with extended visual sequelae after the inflation of a driver's airbag during a head-on collision. The superficial facial lesions were accompanied by bilateral eye lesions, reaching both the anterior and posterior segments. Bilateral periorbital palpebral hematomas; voluminous bipalpebral edema combined with severe -conjunctival edema, corneal erosions, and edema; bilateral hyphema; pupillary changes with multiple iris sphincter breaks and weak pupillary light reflex only on the right eye; retrocession of the iridocorneal angle; and on fundus examination both retinas had posterior and peripheral hemorrhages and Berlin retinal edema. Five years after the trauma and 4 years after posttraumatic surgery for cataract that had progressively appeared on the left eye, the visual acuity is 25/20 in both eyes notwithstanding a small paracentral scotoma related to a break in the Bruch membrane. A review of the literature shows several types of ophthalmological lesions related to the airbag mechanism, which after combustion of an alkaline powder inflates at a very high speed, resulting in a risk of corneal-conjunctive-palpebral alkaline burns added to an eye contusion, which may be responsible for severe lesions. The American studies distinguish three factors affecting the seriousness of these airbag accidents: (a) wearing glasses, (b) position and size of the driver, and (c) inflation force of the airbag. Wearing a seatbelt is mandatory to minimize the violence of the oculofacial impact. After facial trauma from an airbag, an ophthalmological examination is necessary to assess of the chemical burns of the tissues exposed to the alkaline powder and possible major ocular lesions.

Brain activation for lexical decision and reading aloud: two sides of the same coin?

PubMed

Carreiras, Manuel; Mechelli, Andrea; Estévez, Adelina; Price, Cathy J

2007-03-01

This functional magnetic resonance imaging study compared the neuronal implementation of word and pseudoword processing during two commonly used word recognition tasks: lexical decision and reading aloud. In the lexical decision task, participants made a finger-press response to indicate whether a visually presented letter string is a word or a pseudoword (e.g., "paple"). In the reading-aloud task, participants read aloud visually presented words and pseudowords. The same sets of words and pseudowords were used for both tasks. This enabled us to look for the effects of task (lexical decision vs. reading aloud), lexicality (words vs. nonwords), and the interaction of lexicality with task. We found very similar patterns of activation for lexical decision and reading aloud in areas associated with word recognition and lexical retrieval (e.g., left fusiform gyrus, posterior temporal cortex, pars opercularis, and bilateral insulae), but task differences were observed bilaterally in sensorimotor areas. Lexical decision increased activation in areas associated with decision making and finger tapping (bilateral postcentral gyri, supplementary motor area, and right cerebellum), whereas reading aloud increased activation in areas associated with articulation and hearing the sound of the spoken response (bilateral precentral gyri, superior temporal gyri, and posterior cerebellum). The effect of lexicality (pseudoword vs. words) was also remarkably consistent across tasks. Nevertheless, increased activation for pseudowords relative to words was greater in the left precentral cortex for reading than lexical decision, and greater in the right inferior frontal cortex for lexical decision than reading. We attribute these effects to differences in the demands on speech production and decision-making processes, respectively.

Multimodal image analysis of the retina in Hunter syndrome (mucopolysaccharidosis type II): Case report.

PubMed

Salvucci, Isadora Darriba Macedo; Finzi, Simone; Oyamada, Maria Kiyoko; Kim, Chong Ae; Pimentel, Sérgio Luis Gianotti

2018-01-01

We report a case of retinal and posterior ocular findings in a 33-year-old man diagnosed with Hunter syndrome (Mucopolysaccharidosis type II) in a multimodal imaging way. Our patient was complaining of blurred night vision for the past 3 years. He had not received any systemic treatment for Hunter syndrome. Vision acuity was 20/20 in both eyes and corneas were clear. Fundus examination revealed bilateral crowded and hyperemic optic nerve heads (elevated in the ocular ultrasound) and areas of subretinal hypopigmentation. There was hyperautofluorescence at the central fovea and perifovea, and a diffuse bilateral choroidal fluorescence in angiography. Macular SD-OCT showed a thinning of the external retina at the perifovea in both eyes. Visual field testing showed a bilateral ring scotoma. The full field ERG was subnormal, with a negative response in the scotopic phase. Visual Evoked Potencial test and cranial MRI were normal. Our multimodal analysis reported here attempted to contribute to the knowledge of the natural history of GAG deposition in the eye, focusing on the retina and retinal pigment epithelium. Defining this natural history is essential for a proper comparison with Hunter patients receiving systemic treatment, thus determining if it can or cannot improve retinal function in humans with this disorder.

Absence of distracting information explains the redundant signals effect for a centrally presented categorization task.

PubMed

Mishler, Ada D; Neider, Mark B

2017-11-01

The redundant signals effect, a speed-up in response times with multiple targets compared to a single target in one display, is well-documented, with some evidence suggesting that it can occur even in conceptual processing when targets are presented bilaterally. The current study was designed to determine whether or not category-based redundant signals can speed up processing even without bilateral presentation. Toward that end, participants performed a go/no-go visual task in which they responded only to members of the target category (i.e., they responded only to numbers and did not respond to letters). Numbers and letters were presented along an imaginary vertical line in the center of the visual field. When the single signal trials contained a nontarget letter (Experiment 1), there was a significant redundant signals effect. The effect was not significant when the single-signal trials did not contain a nontarget letter (Experiments 2 and 3). The results indicate that, when targets are defined categorically and not presented bilaterally, the redundant signals effect may be an effect of reducing the presence of information that draws attention away from the target. This suggests that redundant signals may not speed up conceptual processing when interhemispheric presentation is not available. Copyright © 2017 Elsevier B.V. All rights reserved.

Identification of a novel mutation in the PTCH gene in a patient with Gorlin-Goltz syndrome with unusual ocular disorders.

PubMed

Romano, Mary; Iacovello, Daniela; Cascone, Nikhil C; Contestabile, Maria Teresa

2011-01-01

To document the clinical, functional, and in vivo microanatomic characteristics of a patient with Gorlin-Goltz syndrome with a novel nonsense mutation in PTCH (patched). Optical coherence tomography (OCT), fluorescein angiography, electrophysiologic testing, visual field, magnetic resonance imaging, and mutation screening of PTCH gene. Visual acuity was 20/20 in the right eye and 20/25 in the left. Fundus examination revealed myelinated nerve fibers in the left eye and bilateral epiretinal membranes with lamellar macular hole also documented with macular OCT. A reduction of the retinal nerve fiber layers in both eyes was found with fiber nervous OCT. Fluorescein angiography showed bilaterally foveal hyperfluorescence and the visual field revealed inferior hemianopia in the right eye. Pattern visual evoked potentials registered a reduction of amplitude in both eyes and latency was delayed in the left eye. Pattern electroretinogram showed a reduction in P50 and N95 peak time and a delay in P50 peak time in the left eye. Flash electroretinogram was reduced in rod response, maximal response, and oscillatory potentials in both eyes. Cone response was normal and 30-Hz flicker was slightly reduced in both eyes. Mutation screening identified a novel nonsense mutation in PTCH. A novel nonsense mutation in the PTCH gene was found. We report the occurrence of epiretinal membranes and the persistence of myelinated nerve fibers. Electrophysiologic and visual field alterations, supporting a neuroretinal dysfunction, were also documented.

Progressive posterior cortical dysfunction

PubMed Central

Porto, Fábio Henrique de Gobbi; Machado, Gislaine Cristina Lopes; Morillo, Lilian Schafirovits; Brucki, Sonia Maria Dozzi

2010-01-01

Progressive posterior cortical dysfunction (PPCD) is an insidious syndrome characterized by prominent disorders of higher visual processing. It affects both dorsal (occipito-parietal) and ventral (occipito-temporal) pathways, disturbing visuospatial processing and visual recognition, respectively. We report a case of a 67-year-old woman presenting with progressive impairment of visual functions. Neurologic examination showed agraphia, alexia, hemispatial neglect (left side visual extinction), complete Balint’s syndrome and visual agnosia. Magnetic resonance imaging showed circumscribed atrophy involving the bilateral parieto-occipital regions, slightly more predominant to the right. Our aim was to describe a case of this syndrome, to present a video showing the main abnormalities, and to discuss this unusual presentation of dementia. We believe this article can contribute by improving the recognition of PPCD. PMID:29213665

Enhancing links between visual short term memory, visual attention and cognitive control processes through practice: An electrophysiological insight.

PubMed

Fuggetta, Giorgio; Duke, Philip A

2017-05-01

The operation of attention on visible objects involves a sequence of cognitive processes. The current study firstly aimed to elucidate the effects of practice on neural mechanisms underlying attentional processes as measured with both behavioural and electrophysiological measures. Secondly, it aimed to identify any pattern in the relationship between Event-Related Potential (ERP) components which play a role in the operation of attention in vision. Twenty-seven participants took part in two recording sessions one week apart, performing an experimental paradigm which combined a match-to-sample task with a memory-guided efficient visual-search task within one trial sequence. Overall, practice decreased behavioural response times, increased accuracy, and modulated several ERP components that represent cognitive and neural processing stages. This neuromodulation through practice was also associated with an enhanced link between behavioural measures and ERP components and with an enhanced cortico-cortical interaction of functionally interconnected ERP components. Principal component analysis (PCA) of the ERP amplitude data revealed three components, having different rostro-caudal topographic representations. The first component included both the centro-parietal and parieto-occipital mismatch triggered negativity - involved in integration of visual representations of the target with current task-relevant representations stored in visual working memory - loaded with second negative posterior-bilateral (N2pb) component, involved in categorising specific pop-out target features. The second component comprised the amplitude of bilateral anterior P2 - related to detection of a specific pop-out feature - loaded with bilateral anterior N2, related to detection of conflicting features, and fronto-central mismatch triggered negativity. The third component included the parieto-occipital N1 - related to early neural responses to the stimulus array - which loaded with the second negative posterior-contralateral (N2pc) component, mediating the process of orienting and focusing covert attention on peripheral target features. We discussed these three components as representing different neurocognitive systems modulated with practice within which the input selection process operates. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

[Bilateral spontaneously reattached rhegmatogenous retinal detachment. Case report and differential diagnosis with pigmentary retinopathies].

PubMed

García-Guzmán, Jorge Guillermo; Franco-Yáñez, Yasmín; Lima-Gómez, Virgilio

2014-01-01

A dark pigmentation of the ocular fundus presents in degenerative diseases such as retinitis pigmentosa; this disease must be distinguished from others whose evolution is not progressive, in order to estimate the functional prognosis of the patient. To analyze the features which distinguish spontaneously reattached retinal detachment from other causes of ocular fundus pigmentation, in order to be able to identify it even in bilateral cases. A case of a female with chronic visual loss is presented, who was referred for evaluation with the diagnosis of a pigmented retinopathy. Clinical exploration discarded causes as retinitis pigmentosa, retinal inflammatory diseases or trauma. Based on the clinical features, on the topography of pigmentation and in the information provided by electroretinography, a bilateral spontaneous reattachment of rhegmatogenous retinal detachment was diagnosed made. Clinical features of this entity are discussed, as well as the diagnostic approach to distinguish it from other pigment retinopathies. Clinical features of spontaneously reattached retinal detachment allow the explorer to distinguish it from other causes of bilateral pigmentation, despite presenting bilaterally. Since the prognosis of the attached retina is better than that of a degenerative disease, the correct diagnosis makes rehabilitation easier.

Contrast-balanced binocular treatment in children with deprivation amblyopia.

PubMed

Hamm, Lisa M; Chen, Zidong; Li, Jinrong; Dai, Shuan; Black, Joanna; Yuan, Junpeng; Yu, Minbin; Thompson, Benjamin

2017-11-28

Children with deprivation amblyopia due to childhood cataract have been excluded from much of the emerging research into amblyopia treatment. An investigation was conducted to determine whether contrast-balanced binocular treatment - a strategy currently being explored for children with anisometropic and strabismic amblyopia - may be effective in children with deprivation amblyopia. An unmasked, case-series design intended to assess proof of principle was employed. Eighteen children with deprivation amblyopia due to childhood cataracts (early bilateral n = 7, early unilateral n = 7, developmental n = 4), as well as 10 children with anisometropic (n = 8) or mixed anisometropic and strabismic amblyopia (n = 2) were prescribed one hour a day of treatment over a six-week period. Supervised treatment was available. Visual acuity, contrast sensitivity, global motion perception and interocular suppression were measured pre- and post-treatment. Visual acuity improvements occurred in the anisometropic/strabismic group (0.15 ± 0.05 logMAR, p = 0.014), but contrast sensitivity did not change. As a group, children with deprivation amblyopia had a smaller but statistically significant improvement in weaker eye visual acuity (0.09 ± 0.03 logMAR, p = 0.004), as well a significant improvement in weaker eye contrast sensitivity (p = 0.004). Subgroup analysis suggested that the children with early bilateral deprivation had the largest improvements, while children with early unilateral cataract did not improve. Interestingly, binocular contrast sensitivity also improved in children with early bilateral deprivation. Global motion perception improved for both subgroups with early visual deprivation, as well as children with anisometropic or mixed anisometropic/strabismic amblyopia. Interocular suppression improved for all subgroups except children with early unilateral deprivation. These data suggest that supervised contrast-balanced binocular treatment should be further investigated as a treatment option for children with deprivation amblyopia. However, for children with more severe deprivation amblyopia due to early unilateral cataracts, supplementary or alternative options should also be explored. © 2017 Optometry Australia.

Stages of functional processing and the bihemispheric recognition of Japanese Kana script.

PubMed

Yoshizaki, K

2000-04-01

Two experiments were carried out in order to examine the effects of functional steps on the benefits of interhemispheric integration. The purpose of Experiment 1 was to investigate the validity of the Banich (1995a) model, where the benefits of interhemispheric processing increase as the task involves more functional steps. The 16 right-handed subjects were given two types of Hiragana-Katakana script matching tasks. One was the Name Identity (NI) task, and the other was the vowel matching (VM) task, which involved more functional steps compared to the NI task. The VM task required subjects to make a decision whether or not a pair of Katakana-Hiragana scripts had a common vowel. In both tasks, a pair of Kana scripts (Katakana-Hiragana scripts) was tachistoscopically presented in the unilateral visual fields or the bilateral visual fields, where each letter was presented in each visual field. A bilateral visual fields advantage (BFA) was found in both tasks, and the size of this did not differ between the tasks, suggesting that these findings did not support the Banich model. The purpose of Experiment 2 was to examine the effects of imbalanced processing load between the hemispheres on the benefits of interhemispheric integration. In order to manipulate the balance of processing load across the hemispheres, the revised vowel matching (r-VM) task was developed by amending the VM task. The r-VM task was the same as the VM task in Experiment 1, except that a script that has only vowel sound was presented as a counterpart of a pair of Kana scripts. The 24 right-handed subjects were given the r-VM and NI tasks. The results showed that although a BFA showed up in the NI task, it did not in the r-VM task. These results suggested that the balance of processing load between hemispheres would have an influence on the bilateral hemispheric processing.

Genetic Factors of Ophthalmic Importance.

ERIC Educational Resources Information Center

Pollard, Zane F.

Reviewed are chromosomal anomalies affecting one's eyes. Brief descriptions are given of the genetic etiology of bilateral retinoblastoma (malignant tumors), aniridia (absence of the iris), cataracts, congenital glaucoma, Reginitis Pigmentosa (progressive deterioration of the visual cells), Choroidermia (degeneration of the vascular coat of the…

Bilateral mandibular pyogranulomatous lymphadenitis and pulmonary nodules in a dog with Bartonella henselae bacteremia

PubMed Central

Tucker, Melissa D.; Sellon, Rance K.; Tucker, Russell L.; Wills, Tamara B.; Simonsen, Andrea; Maggi, Ricardo G.; Breitschwerdt, Edward B.

2014-01-01

This report describes a 2-year-old collie dog with pulmonary nodules, visualized by computed tomographic (CT) scan, with evidence of Bartonella henselae bacteremia and pyogranulomatous lymphadenitis. Clinical signs resolved with antimicrobial therapy. PMID:25320386

Thinking about Eating Food Activates Visual Cortex with Reduced Bilateral Cerebellar Activation in Females with Anorexia Nervosa: An fMRI Study

PubMed Central

Brooks, Samantha J.; O'Daly, Owen; Uher, Rudolf; Friederich, Hans-Christoph; Giampietro, Vincent; Brammer, Michael; Williams, Steven C. R.; Schiöth, Helgi B.; Treasure, Janet; Campbell, Iain C.

2012-01-01

Background Women with anorexia nervosa (AN) have aberrant cognitions about food and altered activity in prefrontal cortical and somatosensory regions to food images. However, differential effects on the brain when thinking about eating food between healthy women and those with AN is unknown. Methods Functional magnetic resonance imaging (fMRI) examined neural activation when 42 women thought about eating the food shown in images: 18 with AN (11 RAN, 7 BPAN) and 24 age-matched controls (HC). Results Group contrasts between HC and AN revealed reduced activation in AN in the bilateral cerebellar vermis, and increased activation in the right visual cortex. Preliminary comparisons between AN subtypes and healthy controls suggest differences in cortical and limbic regions. Conclusions These preliminary data suggest that thinking about eating food shown in images increases visual and prefrontal cortical neural responses in females with AN, which may underlie cognitive biases towards food stimuli and ruminations about controlling food intake. Future studies are needed to explicitly test how thinking about eating activates restraint cognitions, specifically in those with restricting vs. binge-purging AN subtypes. PMID:22479499

Rapid assessment of avoidable blindness in Bhutan.

PubMed

Lepcha, Nor Tshering; Chettri, Chandra Kumar; Getshen, Kunzang; Rai, Bhim Bahadur; Ramaswamy, Shamanna Bindiganavale; Saibaba, Saravanan; Nirmalan, Praveen Kumar; Demarchis, Emilia Hansson; Tabin, Geoffrey; Morley, Michael; Morley, Katharine

2013-08-01

To conduct a rapid assessment of avoidable blindness survey in Bhutan to obtain estimates of blindness, visual impairment, and cataract surgical coverage, outcomes and barriers among persons ≥50 years old. A total of 82 clusters of 50 people ≥50 years were selected using probability proportionate to size sampling. Eligible participants were selected from households using compact segment sampling, and underwent ophthalmic examination for visual acuity, followed by penlight and direct ophthalmoscopy. Participants with cataract were interviewed regarding surgical outcomes and barriers to surgery. Overall, 4046 of 4100 persons enumerated (98.7%) underwent ophthalmic examination. Adjusting for age and sex, the prevalence of bilaterally blind persons with available correction was 1.5% (95% confidence interval 1.09-1.89). Most blindness (67.1%) and severe visual impairment (74.1%) resulted from cataract, but 22.1% resulted from posterior segment pathology. Cataract surgical coverage for bilaterally blind persons was 72.7%. Almost 90% of patients reported moderate or good satisfaction, despite poor surgical outcomes in 23.6%. The prevalence of blindness in people aged ≥50 years in Bhutan was relatively low when compared with neighboring countries and World Health Organization sub-region estimates. Areas for improvement include community outreach, surgical outcomes, and posterior segment diseases.

Basic multisensory functions can be acquired after congenital visual pattern deprivation in humans.

PubMed

Putzar, Lisa; Gondan, Matthias; Röder, Brigitte

2012-01-01

People treated for bilateral congenital cataracts offer a model to study the influence of visual deprivation in early infancy on visual and multisensory development. We investigated cross-modal integration capabilities in cataract patients using a simple detection task that provided redundant information to two different senses. In both patients and controls, redundancy gains were consistent with coactivation models, indicating an integrated processing of modality-specific information. This finding is in contrast with recent studies showing impaired higher-level multisensory interactions in cataract patients. The present results suggest that basic cross-modal integrative processes for simple short stimuli do not depend on visual and/or crossmodal input since birth.

[Uveitis: diagnostic approach].

PubMed

Martínez-Berriotxoa, A; Fonollosa, A; Artaraz, J

2012-10-01

A 32 year-old woman was referred from the Ophthalmology Department to rule out a possible systemic disease. Her only past medical history of relevance was a tuberculosis contact during childhood. She complained of floaters and progressive blurring of vision in both eyes for some months, as well as arthralgia and cough. Her visual acuity was 0.3 in the right eye and 0.4 in the left eye. Biomicroscopy showed bilateral anterior granulomatous uveitis (1+ cells). Funduscopy showed bilateral vitritis 3+, snow banking and peripheral phlebitis. Fluorescein angiography did not show central vasculitis, and optical coherence tomography showed bilateral cystoid macular oedema. Fundus autofluorescence was normal. How would you initially assess this patient in order to decide which systemic examination should be performed, bearing in mind the ophthalmological manifestations? Copyright © 2011 Elsevier España, S.L. All rights reserved.

Annual Summary Report, 15 June 1960-14 June 1961,

DTIC Science & Technology

The habituation and the dishabituation of the visual responses to repetitive light flashes were investigated in the cerveau isole cat. The...system show that EEG synchronization increases following bilateral withdrawal of the retinal dark discharge in the cerveau isole cat, and following

Fulminant idiopathic intracranial hypertension and venous stasis retinopathy resulting in severe bilateral visual impairment.

PubMed

Voldman, Alexander; Durbin, Breanna; Nguyen, John; Ellis, Brian; Leys, Monique

2017-03-10

To report a complicated case of fulminant idiopathic intracranial hypertension and concomitant venous stasis retinopathy leading to postpapilledema optic atrophy. Case report. A 34-year-old morbidly obese woman with a history of idiopathic intracranial hypertension (IIH) presented with a 1-month history of bilateral vision loss, diplopia, and left eye pain after being lost to follow-up for 6 years. Fundus examination revealed florid papilledema with venous tortuosity bilaterally. Brain and orbit magnetic resonance imaging showed bilateral globe flattening, intraocular optic nerve swelling in both eyes, and no abnormality on magnetic resonance venography. After additional workup including lumbar puncture with an opening pressure of 55 cm H2O, a diagnosis of IIH was confirmed. Medical treatment with oral carbonic anhydrase inhibitors was initiated, followed by same-day bilateral optic nerve sheath decompression and ventriculoperitoneal shunt placement the following week. Fundus examination 2 months later revealed a persistent blood and thunder fundus suggestive of bilateral central retinal vein occlusions. Over the course of 6 months, both eyes displayed postpapilledema optic atrophy with light perception and hand motion vision in the right and left eyes, respectively. On Goldmann perimetry, the patient had vague limited isolated responses in both eyes to the largest target. Fulminant IIH can present with profoundly blinding complications recalcitrant to aggressive medical and surgical intervention. Central retinal vein occlusion is an uncommon blinding complication of IIH.

Visual attention capacity: a review of TVA-based patient studies.

PubMed

Habekost, Thomas; Starrfelt, Randi

2009-02-01

Psychophysical studies have identified two distinct limitations of visual attention capacity: processing speed and apprehension span. Using a simple test, these cognitive factors can be analyzed by Bundesen's Theory of Visual Attention (TVA). The method has strong specificity and sensitivity, and measurements are highly reliable. As the method is theoretically founded, it also has high validity. TVA-based assessment has recently been used to investigate a broad range of neuropsychological and neurological conditions. We present the method, including the experimental paradigm and practical guidelines to patient testing, and review existing TVA-based patient studies organized by lesion anatomy. Lesions in three anatomical regions affect visual capacity: The parietal lobes, frontal cortex and basal ganglia, and extrastriate cortex. Visual capacity thus depends on large, bilaterally distributed anatomical networks that include several regions outside the visual system. The two visual capacity parameters are functionally separable, but seem to rely on largely overlapping brain areas.

Perceptual congruency of audio-visual speech affects ventriloquism with bilateral visual stimuli.

PubMed

Kanaya, Shoko; Yokosawa, Kazuhiko

2011-02-01

Many studies on multisensory processes have focused on performance in simplified experimental situations, with a single stimulus in each sensory modality. However, these results cannot necessarily be applied to explain our perceptual behavior in natural scenes where various signals exist within one sensory modality. We investigated the role of audio-visual syllable congruency on participants' auditory localization bias or the ventriloquism effect using spoken utterances and two videos of a talking face. Salience of facial movements was also manipulated. Results indicated that more salient visual utterances attracted participants' auditory localization. Congruent pairing of audio-visual utterances elicited greater localization bias than incongruent pairing, while previous studies have reported little dependency on the reality of stimuli in ventriloquism. Moreover, audio-visual illusory congruency, owing to the McGurk effect, caused substantial visual interference on auditory localization. Multisensory performance appears more flexible and adaptive in this complex environment than in previous studies.

Visual Disability Among Juvenile Open-angle Glaucoma Patients.

PubMed

Gupta, Viney; Ganesan, Vaitheeswaran L; Kumar, Sandip; Chaurasia, Abadh K; Malhotra, Sumit; Gupta, Shikha

2018-04-01

Juvenile onset primary open-angle glaucoma (JOAG) unlike adult onset primary open-angle glaucoma presents with high intraocular pressure and diffuse visual field loss, which if left untreated leads to severe visual disability. The study aimed to evaluate the extent of visual disability among JOAG patients presenting to a tertiary eye care facility. Visual acuity and perimetry records of unrelated JOAG patients presenting to our Glaucoma facility were analyzed. Low vision and blindness was categorized by the WHO criteria and percentage impairment was calculated as per the guidelines provided by the American Medical Association (AMA). Fifty-two (15%) of the 348 JOAG patients were bilaterally blind at presentation and 32 (9%) had low vision according to WHO criteria. Ninety JOAG patients (26%) had a visual impairment of 75% or more. Visual disability at presentation among JOAG patients is high. This entails a huge economic burden, given their young age and associated social responsibilities.

Pain-evoked trunk muscle activity changes during fatigue and DOMS.

PubMed

Larsen, L H; Hirata, R P; Graven-Nielsen, T

2017-05-01

Muscle pain may reorganize trunk muscle activity but interactions with exercise-related muscle fatigue and delayed onset muscle soreness (DOMS) is to be clarified. In 19 healthy participants, the trunk muscle activity during 20 multi-directional unpredictable surface perturbations were recorded after bilateral isotonic saline injections (control) and during unilateral and bilateral hypertonic saline-induced low back pain (LBP) in conditions of back muscle fatigue (Day-1) and DOMS (Day-2). Pain intensity and distribution were assessed by visual analogue scale (VAS) scores and pain drawings. The degree of fatigue and DOMS were assessed by Likert scale scores. Root-mean-square electromyographic (RMS-EMG) signals were recorded post-perturbation from six bilateral trunk muscles and the difference from baseline conditions (Delta-RMS-EMG) was extracted and averaged across abdominal and back muscles. In DOMS, peak VAS scores were higher during bilateral control and bilateral saline-induced pain than fatigue (p < 0.001) and during bilateral compared with unilateral pain (p < 0.001). The saline-induced pain areas were larger during DOMS than fatigue (p < 0.01). In response to surface perturbations during fatigue and DOMS, the back muscle Delta-RMS-EMG increased during bilateral compared with unilateral pain and control injections (p < 0.001) and decreased during unilateral pain compared with control injections (p < 0.04). In DOMS compared with fatigue, the post-perturbation Delta-RMS-EMG in back muscles was higher during bilateral pain and lower during unilateral pain (p < 0.001). The abdominal Delta-RMS-EMG was not significantly affected. Facilitated and attenuated back muscle responses to surface perturbations in bilateral and unilateral LBP, respectively, was more expressed during exercise-induced back muscle soreness compared with fatigue. Back muscle activity decreased during unilateral and increased during bilateral pain after unpredictable surface perturbations during muscle fatigue and DOMS. Accumulation effects of DOMS on pain intensity and spreading and trunk muscle activity after pain-induction. © 2017 European Pain Federation - EFIC®.

ELISA-Confirmed Bilateral Ocular Toxocariasis with Different Features.

PubMed

Lee, Tae Hee; Ji, Yong Sok; Lee, Seung Hyun

2015-08-01

To report a rare case of bilateral ocular toxocariasis with a different clinical presentation in each eye. A 56-year-old man presented with severe ocular pain and acute visual loss in the right eye (RE). His best-corrected visual acuity was hand motion in the RE and 20/30 in the left eye (LE). Slit-lamp examination showed a severe anterior chamber reaction in the RE and a moderate anterior chamber reaction in the LE. The fundus of the LE showed a posterior hemorrhagic granuloma with vascular sheathing whereas the fundus of the RE was not visible because of severe vitreous opacification. Blood laboratory testing disclosed hyperproduction of IgE but no eosinophilia. Serum enzyme-linked immunosorbent assay testing was positive for Toxocara canis IgG (1:38). Toxocara antibody was also detected in the aqueous humor from both eyes (RE, 1:321; LE, 1:254). The patient was treated with topical and oral steroids along with oral albendazole. Additionally, phacoemulsification, a therapeutic vitrectomy, and vitreous cultures were performed in the RE. During the vitrectomy, the fundus of the RE showed diffuse retinal vascular obstruction with sheathing. Toxocara antibodies were detected in the vitreous fluid from the RE (1:679). A laser barrier was placed around the granuloma in the LE. After 1 month of steroid therapy, a tapering schedule was started. At 6 months postoperatively, the fundi of both eyes were stable. The final best-corrected visual acuity was 8/20 in the RE and 20/20 in the LE. A rare case of bilateral ocular toxocariasis is reported with a different clinical presentation in each eye that was diagnosed using enzyme-linked immunosorbent assay analysis of intraocular fluids. Both eyes were successfully treated medically with a vitrectomy eventually being required in the RE.

The right posterior inferior frontal gyrus contributes to phonological word decisions in the healthy brain: evidence from dual-site TMS.

PubMed

Hartwigsen, Gesa; Price, Cathy J; Baumgaertner, Annette; Geiss, Gesine; Koehnke, Maria; Ulmer, Stephan; Siebner, Hartwig R

2010-08-01

There is consensus that the left hemisphere plays a dominant role in language processing, but functional imaging studies have shown that the right as well as the left posterior inferior frontal gyri (pIFG) are activated when healthy right-handed individuals make phonological word decisions. Here we used online transcranial magnetic stimulation (TMS) to examine the functional relevance of the right pIFG for auditory and visual phonological decisions. Healthy right-handed individuals made phonological or semantic word judgements on the same set of auditorily and visually presented words while they received stereotactically guided TMS over the left, right or bilateral pIFG (n=14) or the anterior left, right or bilateral IFG (n=14). TMS started 100ms after word onset and consisted of four stimuli given at a rate of 10Hz and intensity of 90% of active motor threshold. Compared to TMS of aIFG, TMS of pIFG impaired reaction times and accuracy of phonological but not semantic decisions for visually and auditorily presented words. TMS over left, right or bilateral pIFG disrupted phonological processing to a similar degree. In a follow-up experiment, the intensity threshold for delaying phonological judgements was identical for unilateral TMS of left and right pIFG. These findings indicate that an intact function of right pIFG is necessary for accurate and efficient phonological decisions in the healthy brain with no evidence that the left and right pIFG can compensate for one another during online TMS. Our findings motivate detailed studies of phonological processing in patients with acute and chronic damage of the right pIFG. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Corneo-scleral contact lenses in an uncommon case of keratoconus with high hyperopia and astigmatism.

PubMed

Porcar, Esteban; Montalt, Juan Carlos; España-Gregori, Enrique; Peris-Martínez, Cristina

2017-10-01

To analyse the visual quality achieved by fitting corneo-scleral contact lenses (CScL) in an uncommon case of bilateral keratoconus, high hyperopia and astigmatism. A 45-year-old man presented for eye examination due to the unsatisfactory quality of his vision wearing soft toric contact lenses. He presented high hyperopia and astigmatism with bilateral keratoconus. He was fitted with CScL to correct his irregular astigmatism and ocular aberrations. A diagnostic trial set was used in the fitting process and he was assessed according to standardised fitting methodology. Visual acuity, corneal topography, biometry and ocular aberrations were evaluated. The follow-up period was 1year. The best spectacle-corrected visual acuity was 20/32 with +8.00/-4.50×30° for the right eye (RE) and 20/25 with +7.75/-2.25×120° for the left eye (LE). After CScL fitting, visual acuity was improved to 20/20 and 20/16 for the RE and LE, respectively. The patient wore these contact lenses an average of 13h a day. The total high order aberrations decreased by approximately 79% in the RE (2.37-0.50μm) and 47% in the LE (1.04-0.55μm) after CScL fitting. Visual quality and wearing time were maintained after 1year wearing CScL. In addition, no adverse ocular effects were found during this period. The present case report describes how the patient had CScL fitted successfully for management of keratoconus with high hyperopia and astigmatism. They provided optimal visual quality, along with prolonged use times and no adverse effects to the cornea. Copyright © 2017 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Visual impairment and blindness in Hungary.

PubMed

Szabó, Dorottya; Sándor, Gábor László; Tóth, Gábor; Pék, Anita; Lukács, Regina; Szalai, Irén; Tóth, Georgina Zsófia; Papp, András; Nagy, Zoltán Zsolt; Limburg, Hans; Németh, János

2018-03-01

The aim of this study was to estimate the prevalence and causes of blindness, severe visual impairment (SVI), moderate visual impairment (MVI), and early visual impairment (EVI) and its causes in an established market economy of Europe. A cross-sectional population-based survey. A sample size of 3675 was calculated using the standard Rapid Assessment of Avoidable Blindness (RAAB) software in Hungary. A total of 105 clusters of 35 people aged 50 years or older were randomly selected with probability proportionate to size by the Hungarian Central Statistical Office. Households within the clusters were selected using compact segment sampling. Visual acuity (VA) was assessed with a Snellen tumbling E-chart with or without a pinhole in the households. The adjusted prevalences of bilateral blindness, SVI, MVI and EVI were 0.9% (95% CI: 0.6-1.2), 0.5% (95% CI: 0.2-0.7), 5.1% (95% CI: 4.3-5.9) and 6.9% (95% CI: 5.9-7.9), respectively. The major causes of blindness in Hungary were age-related macular degeneration (AMD; 27.3%) and other posterior segment diseases (27.3%), cataract (21.2%) and glaucoma (12.1%). Cataract was the main cause of SVI, MVI and EVI. Cataract surgical coverage (CSC) was 90.7%. Of all bilateral blindness in Hungary, 45.5% was considered avoidable. This study proved that RAAB methodology can be successfully conducted in industrialized countries, which often lack reliable epidemiologic data. The prevalence of blindness was relatively low, with AMD and other posterior segment diseases being the leading causes, and cataract is still a significant cause of visual impairment. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

A functional magnetic resonance imaging study mapping the episodic memory encoding network in temporal lobe epilepsy

PubMed Central

Sidhu, Meneka K.; Stretton, Jason; Winston, Gavin P.; Bonelli, Silvia; Centeno, Maria; Vollmar, Christian; Symms, Mark; Thompson, Pamela J.; Koepp, Matthias J.

2013-01-01

Functional magnetic resonance imaging has demonstrated reorganization of memory encoding networks within the temporal lobe in temporal lobe epilepsy, but little is known of the extra-temporal networks in these patients. We investigated the temporal and extra-temporal reorganization of memory encoding networks in refractory temporal lobe epilepsy and the neural correlates of successful subsequent memory formation. We studied 44 patients with unilateral temporal lobe epilepsy and hippocampal sclerosis (24 left) and 26 healthy control subjects. All participants performed a functional magnetic resonance imaging memory encoding paradigm of faces and words with subsequent out-of-scanner recognition assessments. A blocked analysis was used to investigate activations during encoding and neural correlates of subsequent memory were investigated using an event-related analysis. Event-related activations were then correlated with out-of-scanner verbal and visual memory scores. During word encoding, control subjects activated the left prefrontal cortex and left hippocampus whereas patients with left hippocampal sclerosis showed significant additional right temporal and extra-temporal activations. Control subjects displayed subsequent verbal memory effects within left parahippocampal gyrus, left orbitofrontal cortex and fusiform gyrus whereas patients with left hippocampal sclerosis activated only right posterior hippocampus, parahippocampus and fusiform gyrus. Correlational analysis showed that patients with left hippocampal sclerosis with better verbal memory additionally activated left orbitofrontal cortex, anterior cingulate cortex and left posterior hippocampus. During face encoding, control subjects showed right lateralized prefrontal cortex and bilateral hippocampal activations. Patients with right hippocampal sclerosis showed increased temporal activations within the superior temporal gyri bilaterally and no increased extra-temporal areas of activation compared with control subjects. Control subjects showed subsequent visual memory effects within right amygdala, hippocampus, fusiform gyrus and orbitofrontal cortex. Patients with right hippocampal sclerosis showed subsequent visual memory effects within right posterior hippocampus, parahippocampal and fusiform gyri, and predominantly left hemisphere extra-temporal activations within the insula and orbitofrontal cortex. Correlational analysis showed that patients with right hippocampal sclerosis with better visual memory activated the amygdala bilaterally, right anterior parahippocampal gyrus and left insula. Right sided extra-temporal areas of reorganization observed in patients with left hippocampal sclerosis during word encoding and bilateral lateral temporal reorganization in patients with right hippocampal sclerosis during face encoding were not associated with subsequent memory formation. Reorganization within the medial temporal lobe, however, is an efficient process. The orbitofrontal cortex is critical to subsequent memory formation in control subjects and patients. Activations within anterior cingulum and insula correlated with better verbal and visual subsequent memory in patients with left and right hippocampal sclerosis, respectively, representing effective extra-temporal recruitment. PMID:23674488

Trimodal speech perception: how residual acoustic hearing supplements cochlear-implant consonant recognition in the presence of visual cues.

PubMed

Sheffield, Benjamin M; Schuchman, Gerald; Bernstein, Joshua G W

2015-01-01

As cochlear implant (CI) acceptance increases and candidacy criteria are expanded, these devices are increasingly recommended for individuals with less than profound hearing loss. As a result, many individuals who receive a CI also retain acoustic hearing, often in the low frequencies, in the nonimplanted ear (i.e., bimodal hearing) and in some cases in the implanted ear (i.e., hybrid hearing) which can enhance the performance achieved by the CI alone. However, guidelines for clinical decisions pertaining to cochlear implantation are largely based on expectations for postsurgical speech-reception performance with the CI alone in auditory-only conditions. A more comprehensive prediction of postimplant performance would include the expected effects of residual acoustic hearing and visual cues on speech understanding. An evaluation of auditory-visual performance might be particularly important because of the complementary interaction between the speech information relayed by visual cues and that contained in the low-frequency auditory signal. The goal of this study was to characterize the benefit provided by residual acoustic hearing to consonant identification under auditory-alone and auditory-visual conditions for CI users. Additional information regarding the expected role of residual hearing in overall communication performance by a CI listener could potentially lead to more informed decisions regarding cochlear implantation, particularly with respect to recommendations for or against bilateral implantation for an individual who is functioning bimodally. Eleven adults 23 to 75 years old with a unilateral CI and air-conduction thresholds in the nonimplanted ear equal to or better than 80 dB HL for at least one octave frequency between 250 and 1000 Hz participated in this study. Consonant identification was measured for conditions involving combinations of electric hearing (via the CI), acoustic hearing (via the nonimplanted ear), and speechreading (visual cues). The results suggest that the benefit to CI consonant-identification performance provided by the residual acoustic hearing is even greater when visual cues are also present. An analysis of consonant confusions suggests that this is because the voicing cues provided by the residual acoustic hearing are highly complementary with the mainly place-of-articulation cues provided by the visual stimulus. These findings highlight the need for a comprehensive prediction of trimodal (acoustic, electric, and visual) postimplant speech-reception performance to inform implantation decisions. The increased influence of residual acoustic hearing under auditory-visual conditions should be taken into account when considering surgical procedures or devices that are intended to preserve acoustic hearing in the implanted ear. This is particularly relevant when evaluating the candidacy of a current bimodal CI user for a second CI (i.e., bilateral implantation). Although recent developments in CI technology and surgical techniques have increased the likelihood of preserving residual acoustic hearing, preservation cannot be guaranteed in each individual case. Therefore, the potential gain to be derived from bilateral implantation needs to be weighed against the possible loss of the benefit provided by residual acoustic hearing.

Reduced Brain Gray Matter Concentration in Patients With Obstructive Sleep Apnea Syndrome

PubMed Central

Joo, Eun Yeon; Tae, Woo Suk; Lee, Min Joo; Kang, Jung Woo; Park, Hwan Seok; Lee, Jun Young; Suh, Minah; Hong, Seung Bong

2010-01-01

Study Objectives: To investigate differences in brain gray matter concentrations or volumes in patients with obstructive sleep apnea syndrome (OSA) and healthy volunteers. Designs: Optimized voxel-based morphometry, an automated processing technique for MRI, was used to characterize structural differences in gray matter in newly diagnosed male patients. Setting: University hospital Patients and Participants: The study consisted of 36 male OSA and 31 non-apneic male healthy volunteers matched for age (mean age, 44.8 years). Interventions: Using the t-test, gray matter differences were identified. The statistical significance level was set to a false discovery rate P < 0.05 with an extent threshold of kE > 200 voxels. Measurements and Results: The mean apnea-hypopnea index (AHI) of patients was 52.5/ h. On visual inspection of MRI, no structural abnormalities were observed. Compared to healthy volunteers, the gray matter concentrations of OSA patients were significantly decreased in the left gyrus rectus, bilateral superior frontal gyri, left precentral gyrus, bilateral frontomarginal gyri, bilateral anterior cingulate gyri, right insular gyrus, bilateral caudate nuclei, bilateral thalami, bilateral amygdalo-hippocampi, bilateral inferior temporal gyri, and bilateral quadrangular and biventer lobules in the cerebellum (false discovery rate P < 0.05). Gray matter volume was not different between OSA patients and healthy volunteers. Conclusions: The brain gray matter deficits may suggest that memory impairment, affective and cardiovascular disturbances, executive dysfunctions, and dysregulation of autonomic and respiratory control frequently found in OSA patients might be related to morphological differences in the brain gray matter areas. Citation: Joo EY; Tae WS; Lee MJ; Kang JW; Park HS; Lee JY; Suh M; Hong SB. Reduced brain gray matter concentration in patients with obstructive sleep apnea syndrome. SLEEP 2010;33(2):235-241. PMID:20175407

A case of bilateral vocal fold mucosal bridges, bilateral trans-vocal fold type III sulci vocales, and an intracordal polyp.

PubMed

Tan, Melin; Pitman, Michael J

2011-07-01

We present a patient with a novel finding of bilateral mucosal bridges, bilateral type III trans-vocal fold sulci vocales, and a vocal fold polyp. Although sulci and mucosal bridges occur in the vocal folds, it is rare to find multiples of these lesions in a single patient, and it is even more uncommon when they occur in conjunction with a vocal fold polyp. To our knowledge, this is the first description of a vocal fold polyp in combination with multiple vocal fold bridges and multiple type III sulci vocales in a single patient. To describe and visually present the diagnosis and treatment of a patient with an intracordal polyp, bilateral mucosal bridges, as well as bilateral type III trans-vocal fold sulci vocales. Presentation of a set of high definition intraoperative photos displaying the extent of the vocal fold lesions and the resection of the intracordal polyp. This patient presented with only 6 months of significant dysphonia. It was felt that the recent change in voice was because of the polyp and not the bridges or sulci vocales. Considering the patient's presentation and the possible morbidity of resection of mucosal bridges and sulci, only the polyp was excised. Postoperatively, the patient's voice returned to his acceptable mild baseline dysphonia, and the benefit has persisted 6 months postoperatively. The combination of bilateral mucosal bridges, bilateral type III sulcus vocalis, and an intracordal polyp in one patient is rare if not novel. Treatment of the polyp alone returned the patient's voice to his lifelong baseline of mild dysphonia. Copyright © 2011 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Facilitating Access to Emotions: Neural Signature of EMDR Stimulation

PubMed Central

Herkt, Deborah; Tumani, Visal; Grön, Georg; Kammer, Thomas; Hofmann, Arne; Abler, Birgit

2014-01-01

Background Eye Movement Desensitisation and Reprocessing (EMDR) is a method in psychotherapy effective in treating symptoms of posttraumatic stress disorder. The client attends to alternating bilateral visual, auditory or sensory stimulation while confronted with emotionally disturbing material. It is thought that the bilateral stimulation as a specific element of EMDR facilitates accessing and processing of negative material while presumably creating new associative links. We hypothesized that the putatively facilitated access should be reflected in increased activation of the amygdala upon bilateral EMDR stimulation even in healthy subjects. Methods We investigated 22 healthy female university students (mean 23.5 years) with fMRI. Subjects were scanned while confronted with blocks of disgusting and neutral picture stimuli. One third of the blocks was presented without any additional stimulation, one third with bilateral simultaneous auditory stimulation, and one third with bilateral alternating auditory stimulation as used in EMDR. Results Contrasting disgusting vs. neutral picture stimuli confirmed the expected robust effect of amygdala activation for all auditory stimulation conditions. The interaction analysis with the type of auditory stimulation revealed a specific increase in activation of the right amygdala for the bilateral alternating auditory stimulation. Activation of the left dorsolateral prefrontal cortex showed the opposite effect with decreased activation. Conclusions We demonstrate first time evidence for a putative neurobiological basis of the bilateral alternating stimulation as used in the EMDR method. The increase in limbic processing along with decreased frontal activation is in line with theoretical models of how bilateral alternating stimulation could help with therapeutic reintegration of information, and present findings may pave the way for future research on EMDR in the context of posttraumatic stress disorder. PMID:25165974

Sphenoid mucocele with unusual panhypopituitarism.

PubMed

Devi, Saranya; Ganger, Anita; Sharma, Sanjay; Saxena, Rohit

2016-04-05

A 13-year-old boy presented with bilateral progressive proptosis, abduction deficit, optic atrophy and features suggestive of hypopituitarism secondary to a sphenoid sinus mucocele. Drainage of the mucocele along with hormone replacement therapy resulted in improvement in visual acuity and abduction. 2016 BMJ Publishing Group Ltd.

Readout from iconic memory and selective spatial attention involve similar neural processes.

PubMed

Ruff, Christian C; Kristjánsson, Arni; Driver, Jon

2007-10-01

Iconic memory and spatial attention are often considered separately, but they may have functional similarities. Here we provide functional magnetic resonance imaging evidence for some common underlying neural effects. Subjects judged three visual stimuli in one hemifield of a bilateral array comprising six stimuli. The relevant hemifield for partial report was indicated by an auditory cue, administered either before the visual array (precue, spatial attention) or shortly after the array (postcue, iconic memory). Pre- and postcues led to similar activity modulations in lateral occipital cortex contralateral to the cued side. This finding indicates that readout from iconic memory can have some neural effects similar to those of spatial attention. We also found common bilateral activation of a fronto-parietal network for postcue and precue trials. These neuroimaging data suggest that some common neural mechanisms underlie selective spatial attention and readout from iconic memory. Some differences were also found; compared with precues, postcues led to higher activity in the right middle frontal gyrus.

Readout From Iconic Memory and Selective Spatial Attention Involve Similar Neural Processes

PubMed Central

Ruff, Christian C; Kristjánsson, Árni; Driver, Jon

2007-01-01

Iconic memory and spatial attention are often considered separately, but they may have functional similarities. Here we provide functional magnetic resonance imaging evidence for some common underlying neural effects. Subjects judged three visual stimuli in one hemifield of a bilateral array comprising six stimuli. The relevant hemifield for partial report was indicated by an auditory cue, administered either before the visual array (precue, spatial attention) or shortly after the array (postcue, iconic memory). Pre- and postcues led to similar activity modulations in lateral occipital cortex contralateral to the cued side. This finding indicates that readout from iconic memory can have some neural effects similar to those of spatial attention. We also found common bilateral activation of a fronto-parietal network for postcue and precue trials. These neuroimaging data suggest that some common neural mechanisms underlie selective spatial attention and readout from iconic memory. Some differences were also found; compared with precues, postcues led to higher activity in the right middle frontal gyrus. PMID:17894608

Bilateral uveitis and Usher syndrome: a case report.

PubMed

Benson, Matthew D; MacDonald, Ian M

2015-03-15

Usher syndrome is a genetically heterogeneous condition and represents the most common cause of inherited combined vision and hearing loss. Deficits manifest as sensorineural hearing loss that typically develops at a young age and retinitis pigmentosa that can lead to peripheral vision loss and night blindness. As a result, this syndrome can have a significant impact on a patient's quality of life. Previous studies have described an association between Usher syndrome and Fuchs' heterochromic iridocyclitis, a form of non-granulomatous uveitis that generally presents in a unilateral manner. We present a rare finding of bilateral uveitis and, to the best of our knowledge, the first report of granulomatous uveitis as a feature in a patient with Usher syndrome. A 45-year-old Caucasian woman with a known history of retinitis pigmentosa presented to our clinic with suspected Usher syndrome, given her report of long-standing hearing loss. Aside from a mild loss in visual acuity, our patient was otherwise asymptomatic. Visual field testing, audiology and electroretinography findings supported the diagnosis of Usher syndrome. With slit lamp examination she was found to have bilateral keratic precipitates, with large, greasy-white, mutton-fat keratic precipitates on the endothelial surface of her left eye. A thorough work-up that included blood tests and imaging was negative for an alternative cause of her uveitis. We present a rare finding of bilateral uveitis and what we believe to be the first reported instance of mutton-fat keratic precipitates and granulomatous uveitis as a feature in a patient with Usher syndrome. By identifying atypical presentations of the disease, we hope to contribute to the range of ophthalmic conditions that may be seen in association with Usher syndrome.

Bilateral high-frequency stimulation of the subthalamic nucleus on attentional performance: transient deleterious effects and enhanced motivation in both intact and parkinsonian rats

PubMed Central

Baunez, Christelle; Christakou, Anastasia; Chudasama, Yogita; Forni, Claude; Robbins, Trevor W.

2007-01-01

It is now well established that subthalamic nucleus high-frequency stimulation (STN HFS) alleviates motor problems in Parkinson's disease. However, its efficacy for cognitive function remains a matter of debate. The aim of this study was to assess the effects of STN HFS in rats performing a visual attentional task. Bilateral STN HFS was applied in intact and in bilaterally dopamine (DA)-depleted rats. In all animals, STN HFS had a transient debilitating effect on all the variables measured in the task. In DA-depleted rats, STN HFS did not alleviate the deficits induced by the DA lesion such as omissions and latency to make correct responses, but induced perseverative approaches to the food magazine, an indicator of enhanced motivation. In sham-operated controls, STN HFS significantly reduced accuracy and induced perseverative behaviour, mimicking partially the effects of bilateral STN lesions in the same task. These results are in line with the hypothesis that STN HFS only partially mimics inactivation of STN produced by lesioning and confirm the motivational exacerbation induced by STN inactivation. PMID:17331214

The rapid distraction of attentional resources toward the source of incongruent stimulus input during multisensory conflict.

PubMed

Donohue, Sarah E; Todisco, Alexandra E; Woldorff, Marty G

2013-04-01

Neuroimaging work on multisensory conflict suggests that the relevant modality receives enhanced processing in the face of incongruency. However, the degree of stimulus processing in the irrelevant modality and the temporal cascade of the attentional modulations in either the relevant or irrelevant modalities are unknown. Here, we employed an audiovisual conflict paradigm with a sensory probe in the task-irrelevant modality (vision) to gauge the attentional allocation to that modality. ERPs were recorded as participants attended to and discriminated spoken auditory letters while ignoring simultaneous bilateral visual letter stimuli that were either fully congruent, fully incongruent, or partially incongruent (one side incongruent, one congruent) with the auditory stimulation. Half of the audiovisual letter stimuli were followed 500-700 msec later by a bilateral visual probe stimulus. As expected, ERPs to the audiovisual stimuli showed an incongruency ERP effect (fully incongruent versus fully congruent) of an enhanced, centrally distributed, negative-polarity wave starting ∼250 msec. More critically here, the sensory ERP components to the visual probes were larger when they followed fully incongruent versus fully congruent multisensory stimuli, with these enhancements greatest on fully incongruent trials with the slowest RTs. In addition, on the slowest-response partially incongruent trials, the P2 sensory component to the visual probes was larger contralateral to the preceding incongruent visual stimulus. These data suggest that, in response to conflicting multisensory stimulus input, the initial cognitive effect is a capture of attention by the incongruent irrelevant-modality input, pulling neural processing resources toward that modality, resulting in rapid enhancement, rather than rapid suppression, of that input.

Prevalence of blindness and cataract surgical outcomes in Takeo Province, Cambodia.

PubMed

Mörchen, Manfred; Langdon, Toby; Ormsby, Gail M; Meng, Ngy; Seiha, Do; Piseth, Kong; Keeffe, Jill E

2015-01-01

To estimate the prevalence of blindness and cataract surgical outcomes in persons 50 years or older above in Takeo Province, Cambodia. A population based survey. A total of 93 villages were selected through probability proportionate to size using the Rapid Assessment of Avoidable Blindness methodology. Households from 93 villages were selected using compact segment sampling. Visual acuity (VA) of 4650 people 50 years or older was tested and lens status and cause of visual impairment were assessed. The response rate was 96.2%. The age- and sex-adjusted prevalence of bilateral blindness [presenting visual acuity (PVA) <3/60 in the better eye] was 3.4% (95% confidence interval, 2.8%-4.0%), resulting in an estimated 4187 people blind in Takeo Province. The age- and sex-adjusted prevalence of low vision (PVA <6/18 to 3/60) was 21.1%, an estimated 25,900 people. Cataract surgical coverage in the bilaterally blind was 64.7% (female 59.5%, male 78.1%). Cataract surgical outcome was poor (best-corrected visual acuity <6/60) in only 7.7% and good in 88.7% (best-corrected visual acuity ≥6/18) of eyes operated in the last 5 years before the survey. The cataract surgical coverage for women is less than that for men. The increased life expectancy in Cambodia and the fact that women constitute 60.6% of the population (aged ≥50 years) at Takeo Province could have had an impact on cataract workload and high prevalence of blindness. A repeated survey using the same methodology after 8-12 years might be helpful in proving genuine change over time.

The effects of tDCS upon sustained visual attention are dependent on cognitive load.

PubMed

Roe, James M; Nesheim, Mathias; Mathiesen, Nina C; Moberget, Torgeir; Alnæs, Dag; Sneve, Markus H

2016-01-08

Transcranial Direct Current Stimulation (tDCS) modulates the excitability of neuronal responses and consequently can affect performance on a variety of cognitive tasks. However, the interaction between cognitive load and the effects of tDCS is currently not well-understood. We recorded the performance accuracy of participants on a bilateral multiple object tracking task while undergoing bilateral stimulation assumed to enhance (anodal) and decrease (cathodal) neuronal excitability. Stimulation was applied to the posterior parietal cortex (PPC), a region inferred to be at the centre of an attentional tracking network that shows load-dependent activation. 34 participants underwent three separate stimulation conditions across three days. Each subject received (1) left cathodal / right anodal PPC tDCS, (2) left anodal / right cathodal PPC tDCS, and (3) sham tDCS. The number of targets-to-be-tracked was also manipulated, giving a low (one target per visual field), medium (two targets per visual field) or high (three targets per visual field) tracking load condition. It was found that tracking performance at high attentional loads was significantly reduced in both stimulation conditions relative to sham, and this was apparent in both visual fields, regardless of the direction of polarity upon the brain's hemispheres. We interpret this as an interaction between cognitive load and tDCS, and suggest that tDCS may degrade attentional performance when cognitive networks become overtaxed and unable to compensate as a result. Systematically varying cognitive load may therefore be a fruitful direction to elucidate the effects of tDCS upon cognitive functions. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Illusory conjunctions in visual short-term memory: Individual differences in corpus callosum connectivity and splitting attention between the two hemifields.

PubMed

Qin, Shuo; Ray, Nicholas R; Ramakrishnan, Nithya; Nashiro, Kaoru; O'Connell, Margaret A; Basak, Chandramallika

2016-11-01

Overloading the capacity of visual attention can result in mistakenly combining the various features of an object, that is, illusory conjunctions. We hypothesize that if the two hemispheres separately process visual information by splitting attention, connectivity of corpus callosum-a brain structure integrating the two hemispheres-would predict the degree of illusory conjunctions. In the current study, we assessed two types of illusory conjunctions using a memory-scanning paradigm; the features were either presented across the two opposite hemifields or within the same hemifield. Four objects, each with two visual features, were briefly presented together followed by a probe-recognition and a confidence rating for the recognition accuracy. MRI scans were also obtained. Results indicated that successful recollection during probe recognition was better for across hemifields conjunctions compared to within hemifield conjunctions, lending support to the bilateral advantage of the two hemispheres in visual short-term memory. Age-related differences regarding the underlying mechanisms of the bilateral advantage indicated greater reliance on recollection-based processing in young and on familiarity-based processing in old. Moreover, the integrity of the posterior corpus callosum was more predictive of opposite hemifield illusory conjunctions compared to within hemifield illusory conjunctions, even after controlling for age. That is, individuals with lesser posterior corpus callosum connectivity had better recognition for objects when their features were recombined from the opposite hemifields than from the same hemifield. This study is the first to investigate the role of the corpus callosum in splitting attention between versus within hemifields. © 2016 Society for Psychophysiological Research.

Distributed neural signatures of natural audiovisual speech and music in the human auditory cortex.

PubMed

Salmi, Juha; Koistinen, Olli-Pekka; Glerean, Enrico; Jylänki, Pasi; Vehtari, Aki; Jääskeläinen, Iiro P; Mäkelä, Sasu; Nummenmaa, Lauri; Nummi-Kuisma, Katarina; Nummi, Ilari; Sams, Mikko

2017-08-15

During a conversation or when listening to music, auditory and visual information are combined automatically into audiovisual objects. However, it is still poorly understood how specific type of visual information shapes neural processing of sounds in lifelike stimulus environments. Here we applied multi-voxel pattern analysis to investigate how naturally matching visual input modulates supratemporal cortex activity during processing of naturalistic acoustic speech, singing and instrumental music. Bayesian logistic regression classifiers with sparsity-promoting priors were trained to predict whether the stimulus was audiovisual or auditory, and whether it contained piano playing, speech, or singing. The predictive performances of the classifiers were tested by leaving one participant at a time for testing and training the model using the remaining 15 participants. The signature patterns associated with unimodal auditory stimuli encompassed distributed locations mostly in the middle and superior temporal gyrus (STG/MTG). A pattern regression analysis, based on a continuous acoustic model, revealed that activity in some of these MTG and STG areas were associated with acoustic features present in speech and music stimuli. Concurrent visual stimulus modulated activity in bilateral MTG (speech), lateral aspect of right anterior STG (singing), and bilateral parietal opercular cortex (piano). Our results suggest that specific supratemporal brain areas are involved in processing complex natural speech, singing, and piano playing, and other brain areas located in anterior (facial speech) and posterior (music-related hand actions) supratemporal cortex are influenced by related visual information. Those anterior and posterior supratemporal areas have been linked to stimulus identification and sensory-motor integration, respectively. Copyright © 2017 Elsevier Inc. All rights reserved.

Roll-Tilt Perception Using a Somatosensory Bar Task

NASA Technical Reports Server (NTRS)

Black, F. O.; Wade, S. W.; Arshi, A.

1999-01-01

Visual estimates of roll-tilt perception during static roll-tilt are confounded by an offset due to the ocular counterroll that simultaneously occurs. An alternative, non-visual ('somatosensory') measure of roll-tilt perception was developed which is not contaminated by this offset. The aims of this study were to determine: 1) inter-subject variability of somatosensory settings across test session in normal subjects and patients with unilateral or bilateral vestibular loss and 2) intra-subject variability of settings across test session in normal subjects.

Further evidence that amygdala and hippocampus contribute equally to recognition memory.

PubMed

Saunders, R C; Murray, E A; Mishkin, M

1984-01-01

The medial temporal neuropathology found in an amnesic neurosurgical patient [17] was simulated in monkeys in an attempt to determine whether the patient's mnemonic disorder, which had been ascribed to bilateral hippocampal destruction, may have also been due in part to unilateral amygdaloid removal. For this purpose, monkeys were prepared with bilateral hippocampectomy combined with unilateral amygdalectomy, and (as a control) bilateral amygdalectomy combined with unilateral hippocampectomy. The animals were trained both before and after surgery on a one-trial visual recognition task requiring memory of single objects for 10 sec each and then given a postoperative performance test in which their one-trial recognition ability was taxed with longer delays (up to 2 min) and longer lists (up to 10 objects). The two groups, which did not differ reliably at any stage, obtained average scores on the performance test 75 and 80%, respectively. Comparison with the results of an earlier experiment [8] indicates that this performance level lies approximately midway between that of monkeys with amygdaloid or hippocampal removals alone (91%) and that of monkeys with combined amygdalo-hippocampal removals (60%). The results point to a direct quantitative relationship between degree of recognition impairment and amount of conjoint damage to the amygdala and hippocampus irrespective of the specific structure involved. Evidence from neurosurgical cases tested in visual recognition [21] indicates that the same conclusion may apply to man.

Gender differences in brain activation on a mental rotation task.

PubMed

Semrud-Clikeman, Margaret; Fine, Jodene Goldenring; Bledsoe, Jesse; Zhu, David C

2012-10-01

Few neuroimaging studies have explored gender differences on mental rotation tasks. Most studies have utilized samples with both genders, samples mainly consisting of men, or samples with six or fewer females. Graduate students in science fields or liberal arts programs (20 males, 20 females) completed a mental rotation task during functional magnetic resonance imaging (fMRI). When a pair of cube figures was shown, the participant made a keypad response based on whether the pair is the same/similar or different. Regardless of gender, the bilateral middle frontal gyrus, bilateral intraparietal sulcus (IPS), and the left precuneus were activated when a subject tried to solve the mental rotation task. Increased activation in the right inferior frontal gyrus/middle frontal gyrus, the left precuneus/posterior cingulate cortex/cuneus region, and the left middle occipital gyrus was found for men as compared to women. Better accuracy and shorter response times were correlated with an increased activation in the bilateral intraparietal sulcus. No significant brain activity differences related to mental rotation were found between academic majors. These findings suggest that networks involved in visual attention appear to be more strongly activated in the mental rotation tasks in men as compared to women. It also suggests that men use a more automatic process when analyzing complex visual reasoning tasks while women use a more top-down process.

Ocular involvement in paediatric haemolytic uraemic syndrome.

PubMed

Sturm, Veit; Menke, Marcel N; Landau, Klara; Laube, Guido F; Neuhaus, Thomas J

2010-11-01

The aim of this study was to estimate the frequency and severity of ocular involvement in paediatric patients with haemolytic uraemic syndrome (HUS). The study was designed as an institutional, retrospective, observational case series. Charts for all 87 paediatric patients with HUS treated at the University Children's Hospital Zurich between 1995 and 2007 were reviewed. Patients with ocular involvement were identified and clinical findings presented. Three of 69 examined patients with HUS showed ocular involvement. Ophthalmic findings in two children were consistent with bilateral Purtscher retinopathy, showing multiple haemorrhages, exudations and superficial retinal whitening. The third child presented with bilateral isolated central intraretinal haemorrhages as a milder form of ocular involvement. In one of the children with Purtscher retinopathy, laser photocoagulation was required for bilateral rubeosis irides and development of disc neovascularization. Longterm outcomes in the two severely affected children showed decreased visual acuity caused by partial atrophy of the optic nerves. In the milder case visual acuity was not impaired at any time. A minority of paediatric patients with HUS developed ocular involvement. Acute ocular findings varied in severity from isolated intraretinal haemorrhages to Purtscher-like retinopathy with retinal ischaemia. Longterm complications included the development of neovascularizations and consecutive optic nerve atrophy. Although ocular involvement in HUS seems to be rare, physicians should be aware of this complication because of its possible vision-endangering consequences. © 2009 The Authors. Journal compilation © 2009 Acta Ophthalmol.

Bilateral Macular Edema: A New Ocular Feature of Dandy-Walker Syndrome.

PubMed

Tranos, P; Dervenis, N; Kiouras, S

2017-01-01

To describe a case of bilateral cystoid macular edema in a patient with Dandy-Walker syndrome. An 18-year-old male was referred to our tertiary referral center for evaluation of his decreased visual acuity. Detailed ophthalmic examination and imaging revealed the presence of bilateral cystoid macular edema, which was successfully treated with intravitreal triamcinolone injections (2 mg in 0.05 ml). Recurrence of macular edema developed after a period of approximately four months. This is an unusual ophthalmic manifestation of Dandy-Walker syndrome. Cystoid macular edema should be included in the differential diagnosis of subjects with Dandy-Walker syndrome presenting with decreased vision. The pathogenetic mechanism for the development macular edema in this case is not clear. Intravitreal triamcinolone is an effective treatment, but edema was recurrent in our case. Other approaches (such as oral Acetazolamide or intravitreal Anti-VEGF) have to be considered as well.

Dysthyroid Orbitopathy Presenting with Gaze-Evoked Amaurosis: Case Report and Review of the Literature.

PubMed

Orlans, Harry O; Bremner, Fion D

2015-01-01

Gaze-evoked amaurosis (GEA) describes visual loss associated with eccentric gaze that recovers when the eye is returned to primary position. Here we describe an unusual case of bilateral GEA as the presenting feature of dysthyroid orbitopathy. This is only the third such case to be reported in the literature and the first to feature bilateral GEA in all positions of gaze without accompanying proptosis or ophthalmoplegia. A 50-year-old man who had recently commenced treatment for thyrotoxicosis presented with a 3-week history of typical GEA in both eyes in all positions of gaze. He subsequently developed a bilateral compressive optic neuropathy which was only partially responsive to high dose steroid therapy. Although an uncommon presenting feature of dysthyroid orbitopathy, GEA is an ominous symptom that may precede sight-threatening optic nerve compromise. When present, early immunosuppressive and/or decompressive treatment should be considered.

Bilateral simultaneous acute angle closure glaucoma precipitated by non-prescription cold and flu medication.

PubMed

Rudkin, Adam K; Gray, Tim L; Awadalla, Mona; Craig, Jamie E

2010-10-01

We present a case of a 63-year-old woman who presented to an ED with bifrontal headache, nausea and vomiting and reduced visual acuity. Examination revealed bilateral elevated intraocular pressures, corneal haze, shallow anterior chambers and poorly reactive, mid-dilated pupils. Diagnosis was made of simultaneous bilateral acute angle closure glaucoma. A complete drug history revealed that she had been using an over-the-counter cold and flu remedy whose active ingredients included atropa belladonna, an herb with anticholinergic properties. It is likely that drug-induced dilatation of the individual's pupils precipitated this angle closure emergency. In the report we discuss the risk factors for angle closure glaucoma, and review the local and systemic drugs known to trigger this sight-threatening emergency. © 2010 The Authors. Emergency Medicine Australasia © 2010 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

MACULAR COLOBOMA IN A CHILD WITH USHER SYNDROME.

PubMed

Ishaq, Mazhar; Mukhtar, Ahsan; Khan, Saim

2015-01-01

Macular coloboma is a rare entity and its concomitance with Usher syndrome is described here. A 14 years male child was studied in detail along with other family members. He underwent two complete ophthalmologic examinations (4-years follow-up), including visual assessment, orthoptic evaluation, colour vision test, visual fields, corneal topography, Optical coherence tomography, fluorescein angiography, and electroretinography. Detailed ophthalmic examination was also conducted on other asymptomatic members of the same family. Patient had sensorineural deafness, poor visual acuity, and progressive visual field impairment in both eyes, bilaterally presenting macular coloboma and atypical retinitis pigmentosa pattern. The other investigated relatives did not show any specific and/or significant ocular disorder. This concurrence represents no genetic pattern and is observed in sporadic cases.

Ventral and Dorsal Pathways Relate Differently to Visual Awareness of Body Postures under Continuous Flash Suppression

PubMed Central

Goebel, Rainer

2018-01-01

Abstract Visual perception includes ventral and dorsal stream processes. However, it is still unclear whether the former is predominantly related to conscious and the latter to nonconscious visual perception as argued in the literature. In this study upright and inverted body postures were rendered either visible or invisible under continuous flash suppression (CFS), while brain activity of human participants was measured with functional MRI (fMRI). Activity in the ventral body-sensitive areas was higher during visible conditions. In comparison, activity in the posterior part of the bilateral intraparietal sulcus (IPS) showed a significant interaction of stimulus orientation and visibility. Our results provide evidence that dorsal stream areas are less associated with visual awareness. PMID:29445766

Handwriting Development, Competency, and Intervention

ERIC Educational Resources Information Center

Feder, Katya P.; Majnemer, Annette

2007-01-01

Failure to attain handwriting competency during the school-age years often has far-reaching negative effects on both academic success and self-esteem. This complex occupational task has many underlying component skills that may interfere with handwriting performance. Fine motor control, bilateral and visual-motor integration, motor planning,…

Movement preparation and execution: differential functional activation patterns after traumatic brain injury.

PubMed

Gooijers, Jolien; Beets, Iseult A M; Albouy, Genevieve; Beeckmans, Kurt; Michiels, Karla; Sunaert, Stefan; Swinnen, Stephan P

2016-09-01

Years following the insult, patients with traumatic brain injury often experience persistent motor control problems, including bimanual coordination deficits. Previous studies revealed that such deficits are related to brain structural white and grey matter abnormalities. Here, we assessed, for the first time, cerebral functional activation patterns during bimanual movement preparation and performance in patients with traumatic brain injury, using functional magnetic resonance imaging. Eighteen patients with moderate-to-severe traumatic brain injury (10 females; aged 26.3 years, standard deviation = 5.2; age range: 18.4-34.6 years) and 26 healthy young adults (15 females; aged 23.6 years, standard deviation = 3.8; age range: 19.5-33 years) performed a complex bimanual tracking task, divided into a preparation (2 s) and execution (9 s) phase, and executed either in the presence or absence of augmented visual feedback. Performance on the bimanual tracking task, expressed as the average target error, was impaired for patients as compared to controls (P < 0.001) and for trials in the absence as compared to the presence of augmented visual feedback (P < 0.001). At the cerebral level, movement preparation was characterized by reduced neural activation in the patient group relative to the control group in frontal (bilateral superior frontal gyrus, right dorsolateral prefrontal cortex), parietal (left inferior parietal lobe) and occipital (right striate and extrastriate visual cortex) areas (P's < 0.05). During the execution phase, however, the opposite pattern emerged, i.e. traumatic brain injury patients showed enhanced activations compared with controls in frontal (left dorsolateral prefrontal cortex, left lateral anterior prefrontal cortex, and left orbitofrontal cortex), parietal (bilateral inferior parietal lobe, bilateral superior parietal lobe, right precuneus, right primary somatosensory cortex), occipital (right striate and extrastriate visual cortices), and subcortical (left cerebellum crus II) areas (P's < 0.05). Moreover, a significant interaction effect between Feedback Condition and Group in the primary motor area (bilaterally) (P < 0.001), the cerebellum (left) (P < 0.001) and caudate (left) (P < 0.05), revealed that controls showed less overlap of activation patterns accompanying the two feedback conditions than patients with traumatic brain injury (i.e. decreased neural differentiation). In sum, our findings point towards poorer predictive control in traumatic brain injury patients in comparison to controls. Moreover, irrespective of the feedback condition, overactivations were observed in traumatically brain injured patients during movement execution, pointing to more controlled processing of motor task performance. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A lightning strike to the head causing a visual cortex defect with simple and complex visual hallucinations

PubMed Central

Kleiter, Ingo; Luerding, Ralf; Diendorfer, Gerhard; Rek, Helga; Bogdahn, Ulrich; Schalke, Berthold

2007-01-01

The case of a 23‐year‐old mountaineer who was hit by a lightning strike to the occiput causing a large central visual field defect and bilateral tympanic membrane ruptures is described. Owing to extreme agitation, the patient was set to a drug‐induced coma for 3 days. After extubation, she experienced simple and complex visual hallucinations for several days, but otherwise recovered largely. Neuropsychological tests revealed deficits in fast visual detection tasks and non‐verbal learning, and indicated a right temporal lobe dysfunction, consistent with a right temporal focus on electroencephalography. Four months after the accident, she developed a psychological reaction consisting of nightmares with reappearance of the complex visual hallucinations and a depressive syndrome. Using the European Cooperation for Lightning Detection network, a meteorological system for lightning surveillance, the exact geographical location and nature of the lightning flash were retrospectively retraced. PMID:17369595

A lightning strike to the head causing a visual cortex defect with simple and complex visual hallucinations

PubMed Central

Kleiter, Ingo; Luerding, Ralf; Diendorfer, Gerhard; Rek, Helga; Bogdahn, Ulrich; Schalke, Berthold

2009-01-01

The case of a 23-year-old mountaineer who was hit by a lightning strike to the occiput causing a large central visual field defect and bilateral tympanic membrane ruptures is described. Owing to extreme agitation, the patient was sent into a drug-induced coma for 3 days. After extubation, she experienced simple and complex visual hallucinations for several days, but otherwise largely recovered. Neuropsychological tests revealed deficits in fast visual detection tasks and non-verbal learning and indicated a right temporal lobe dysfunction, consistent with a right temporal focus on electroencephalography. At 4 months after the accident, she developed a psychological reaction consisting of nightmares, with reappearance of the complex visual hallucinations and a depressive syndrome. Using the European Cooperation for Lightning Detection network, a meteorological system for lightning surveillance, the exact geographical location and nature of the lightning strike were retrospectively retraced PMID:21734915

Bilateral solar retinopathy. Autofluorescence and optical coherence tomography.

PubMed

Rocha Cabrera, P; Cordovés Dorta, L; González Hernández, M

2016-08-01

A 33-year-old man referred decreased bilateral visual acuity for five years, with no history of interest. Military profession and probably previous sun exposure. Focal pigmented lesions in the macular area of the fundus were observed, with impairment of the photoreceptor layer in the fovea, observed by optical coherence tomography (OCT), in various sectors of the fovea. Solar retinopathy is associated with professions at risk of sun exposure. The diagnosis is based on autofluorescence and macular OCT, that later will provide key data to establish the cause. Copyright © 2016 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

Anton-Babinski syndrome, case report.

PubMed

Martín Juan, A; Madrigal, R; Porta Etessam, J; Sáenz-Francés San Baldomero, F; Santos Bueso, E

2018-05-30

A 22 year-old woman complained about blurred vision after an episode of recovered cardiorespiratory arrest. She had bilateral low visual acuity («count fingers») and no ophthalmological or visual pathways changes. She also had an apparent lack of awareness of the deficit. The Magnetic Resonance Imaging (MRI) showed ischaemic changes in both occipital lobes. As a result, she was diagnosed with Anton-Babinski syndrome. This is a rare disease that should be suspected in strange or poorly congruent visual loss. It is usually due to an ischaemic injury in this region of brain, manifesting itself with low vision not perceived by the patient (visual confabulation). It can simulate a non-organic visual loss or psychiatric disease. Copyright © 2018 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

Exposure to subliminal arousing stimuli induces robust activation in the amygdala, hippocampus, anterior cingulate, insular cortex and primary visual cortex: a systematic meta-analysis of fMRI studies.

PubMed

Brooks, S J; Savov, V; Allzén, E; Benedict, C; Fredriksson, R; Schiöth, H B

2012-02-01

Functional Magnetic Resonance Imaging (fMRI) demonstrates that the subliminal presentation of arousing stimuli can activate subcortical brain regions independently of consciousness-generating top-down cortical modulation loops. Delineating these processes may elucidate mechanisms for arousal, aberration in which may underlie some psychiatric conditions. Here we are the first to review and discuss four Activation Likelihood Estimation (ALE) meta-analyses of fMRI studies using subliminal paradigms. We find a maximum of 9 out of 12 studies using subliminal presentation of faces contributing to activation of the amygdala, and also a significantly high number of studies reporting activation in the bilateral anterior cingulate, bilateral insular cortex, hippocampus and primary visual cortex. Subliminal faces are the strongest modality, whereas lexical stimuli are the weakest. Meta-analyses independent of studies using Regions of Interest (ROI) revealed no biasing effect. Core neuronal arousal in the brain, which may be at first independent of conscious processing, potentially involves a network incorporating primary visual areas, somatosensory, implicit memory and conflict monitoring regions. These data could provide candidate brain regions for the study of psychiatric disorders associated with aberrant automatic emotional processing. Copyright © 2011 Elsevier Inc. All rights reserved.

[A rare cause of optic neuropathy: Cassava].

PubMed

Zeboulon, P; Vignal-Clermont, C; Baudouin, C; Labbé, A

2016-06-01

Cassava root is a staple food for almost 500 million people worldwide. Excessive consumption of it is a rare cause of optic neuropathy. Ten patients diagnosed with cassava root related optic neuropathy were included in this retrospective study. Diagnostic criteria were a bilateral optic neuropathy preceded by significant cassava root consumption. Differential diagnoses were excluded through a neuro-ophthalmic examination, blood tests and a brain MRI. All patients had visual field examination and OCT retinal nerve fiber layer (RNFL) analysis as well as an evaluation of their cassava consumption. All patients had a bilateral optic nerve head atrophy or pallor predominantly located into the temporal sector. Visual field defects consisted of a central or cecocentral scotoma for all patients. RNFL showed lower values only in the temporal sector. Mean duration of cassava consumption prior to the appearance of visual symptoms was 22.7±11.2 years with a mean of 2.57±0.53 cassava-based meals per week. Cassava related optic neuropathy is possibly due to its high cyanide content and enabled by a specific amino-acid deficiency. Cassava root chronic consumption is a rare, underappreciated cause of optic neuropathy and its exact mechanism is still uncertain. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Multifocal Intraocular Lens Results in Correcting Presbyopia in Eyes After Radial Keratotomy.

PubMed

Kim, Kyeong Hwan; Seok, Kyung-Won; Kim, Wan Soo

2017-11-01

To report results of multifocal intraocular lens (IOL) implantation in 2 patients with refractive error and presbyopia after previous radial keratotomy (RK). A refractive multifocal IOL with rotational asymmetry (LS313-MF30; Oculentis, Berlin, Germany) was implanted. The first patient was a 60-year-old man with myopia who underwent unilateral RK 20 years before. His uncorrected distance visual acuity (UDVA) was 20/400, and his distance corrected near vision was J9 in both eyes. Six months after bilateral surgery, his binocular UDVA and uncorrected near visual acuity (UNVA) improved to 20/20 and J1, respectively, although he experienced diurnal fluctuation. The second patient was a 55-year-old woman with hyperopia who underwent bilateral RK 18 years before. Uncorrected distance visual acuity was 20/25 in both eyes, but UNVA was between J9 and J10. Three months after unilateral surgery, UDVA and UNVA of the postsurgical eye improved to 20/20 and J1, respectively. Neither patient reported any significant photic phenomena, and both were satisfied with the results of treatment. The desirable clinical outcomes and levels of satisfaction expressed by these patients indicate that surgery using this particular multifocal IOL may benefit presbyopic patients with previous RK.

Refractive errors in children with autism in a developing country.

PubMed

Ezegwui, I R; Lawrence, L; Aghaji, A E; Okoye, O I; Okoye, O; Onwasigwe, E N; Ebigbo, P O

2014-01-01

In a resource-limited country visual problems of mentally challenged individuals are often neglected. The present study aims to study refractive errors in children diagnosed with autism in a developing country. Ophthalmic examination was carried out on children diagnosed with autism attending a school for the mentally challenged in Enugu, Nigeria between December 2009 and May 2010. Visual acuity was assessed using Lea symbols. Anterior and posterior segments were examined. Cycloplegic refraction was performed. Data was entered on the protocol prepared for the study and analyzed using Statistical Package for the Social Sciences version 17 (Chicago IL, USA). A total of 21 children with autism were enrolled in the school; 18 of whom were examined giving coverage of 85.7%. The age range was 5-15 years, with a mean of 10.28 years (standard deviation ± 3.20). There were 13 boys and 5 girls. One child had bilateral temporal pallor of the disc and one had bilateral maculopathy with diffuse chorioretinal atrophy. Refraction revealed 4 children (22.2%) had astigmatism and 2 children (11.1%) had hypermetropia. Significant refractive error mainly astigmatism was noted in the children with autism. Identifying refractive errors in these children early and providing appropriate corrective lenses may help optimize their visual functioning and impact their activities of daily life in a positive way.

Neural signatures of lexical tone reading.

PubMed

Kwok, Veronica P Y; Wang, Tianfu; Chen, Siping; Yakpo, Kofi; Zhu, Linlin; Fox, Peter T; Tan, Li Hai

2015-01-01

Research on how lexical tone is neuroanatomically represented in the human brain is central to our understanding of cortical regions subserving language. Past studies have exclusively focused on tone perception of the spoken language, and little is known as to the lexical tone processing in reading visual words and its associated brain mechanisms. In this study, we performed two experiments to identify neural substrates in Chinese tone reading. First, we used a tone judgment paradigm to investigate tone processing of visually presented Chinese characters. We found that, relative to baseline, tone perception of printed Chinese characters were mediated by strong brain activation in bilateral frontal regions, left inferior parietal lobule, left posterior middle/medial temporal gyrus, left inferior temporal region, bilateral visual systems, and cerebellum. Surprisingly, no activation was found in superior temporal regions, brain sites well known for speech tone processing. In activation likelihood estimation (ALE) meta-analysis to combine results of relevant published studies, we attempted to elucidate whether the left temporal cortex activities identified in Experiment one is consistent with those found in previous studies of auditory lexical tone perception. ALE results showed that only the left superior temporal gyrus and putamen were critical in auditory lexical tone processing. These findings suggest that activation in the superior temporal cortex associated with lexical tone perception is modality-dependent. © 2014 Wiley Periodicals, Inc.

Repeated intraocular crystallization of ganciclovir in one eye after bilateral intravitreal injections: a case report.

PubMed

Iu, Lawrence P L; Fan, Michelle C Y; Lam, Wai-Ching; Wong, Ian Y H

2018-02-09

Cytomegalovirus (CMV) retinitis is an opportunistic infection that primarily affects immunocompromised individuals. Intravitreal ganciclovir injection monotherapy or in combination with systemic anti-CMV therapy are effective treatments for CMV retinitis. Crystallization of ganciclovir after intravitreal injection is extremely rare. Only two cases had been reported in literature. Crystallization in only one eye after bilateral injections had not been reported before. We hereby report a case of intraocular ganciclovir crystallization in one eye after bilateral intravitreal injections, and repeated crystallization in the same eye after repeated injections. A 79-year-old patient had bilateral cytomegalovirus retinitis and received bilateral intravitreal ganciclovir injections of 2.5 mg in 0.05 ml sterile water. Fundus examination after injection showed formation of needle-shaped, golden-yellow crystals in the vitreous of right eye but not in left eye. The crystals dissolved spontaneously. Repeated bilateral intravitreal ganciclovir injections 4 days later resulted in repeated crystallization of ganciclovir in right eye but not in left eye. The crystals dissolved spontaneously and completely after 5 minutes. Visual acuity remained unchanged and intraocular pressure was normal. Intraocular ganciclovir crystallization could occur after intravitreal injections. It is important to perform fundus examination after injection. The crystals may dissolve rapidly and vitrectomy may not be necessary. Our case suggested intraocular ganciclovir crystallization is an idiosyncratic phenomenon, subjects to distinctive intraocular environment which could be different between two eyes of the same patient. The susceptible intraocular environment could be persistent leading to repeated crystallization.

Inter- and intraobserver reliability of the Rockwood classification in acute acromioclavicular joint dislocations.

PubMed

Schneider, M M; Balke, M; Koenen, P; Fröhlich, M; Wafaisade, A; Bouillon, B; Banerjee, M

2016-07-01

The reliability of the Rockwood classification, the gold standard for acute acromioclavicular (AC) joint separations, has not yet been tested. The purpose of this study was to investigate the reliability of visual and measured AC joint lesion grades according to the Rockwood classification. Four investigators (two shoulder specialists and two second-year residents) examined radiographs (bilateral panoramic stress and axial views) in 58 patients and graded the injury according to the Rockwood classification using the following sequence: (1) visual classification of the AC joint lesion, (2) digital measurement of the coracoclavicular distance (CCD) and the horizontal dislocation (HD) with Osirix Dicom Viewer (Pixmeo, Switzerland), (3) classification of the AC joint lesion according to the measurements and (4) repetition of (1) and (2) after repeated anonymization by an independent physician. Visual and measured Rockwood grades as well as the CCD and HD of every patient were documented, and a CC index was calculated (CCD injured/CCD healthy). All records were then used to evaluate intra- and interobserver reliability. The disagreement between visual and measured diagnosis ranged from 6.9 to 27.6 %. Interobserver reliability for visual diagnosis was good (0.72-0.74) and excellent (0.85-0.93) for measured Rockwood grades. Intraobserver reliability was good to excellent (0.67-0.93) for visual diagnosis and excellent for measured diagnosis (0.90-0.97). The correlations between measurements of the axial view varied from 0.68 to 0.98 (good to excellent) for interobserver reliability and from 0.90 to 0.97 (excellent) for intraobserver reliability. Bilateral panoramic stress and axial radiographs are reliable examinations for grading AC joint injuries according to Rockwood's classification. Clinicians of all experience levels can precisely classify AC joint lesions according to the Rockwood classification. We recommend to grade acute ACG lesions by performing a digital measurement instead of a sole visual diagnosis because of the higher intra- and interobserver reliability. Case series, Level IV.

Long-Term Visual Outcomes of Secondary Intraocular Lens Implantation in Children with Congenital Cataracts

PubMed Central

Jiang, Yongxiang; Lu, Yi

2015-01-01

Aim The aim of this study was to evaluate the long-term visual outcomes and factors affecting visual results in children undergoing secondary intraocular lens (IOL) implantation following primary congenital cataract extraction. Methods Children with congenital cataracts who underwent secondary IOL implantation for aphakia at the Eye and ENT Hospital of Fudan University between January 1, 2001, and December 31, 2007, were retrospectively reviewed. One eye was randomly selected in children with bilateral cataracts. Laterality, type of cataract (total or partial opacity), sex, age at primary and secondary surgeries, visual axis opacity (VAO), compliance with amblyopia therapy, postoperative ocular complications, refractive error, ocular alignment, and best corrected visual acuity (BCVA) at last follow-up were recorded; potential factors that might have affected the visual results were evaluated. Results Seventy-six bilateral and 34 unilateral congenital cataract cases were analyzed; the mean ages of the children were 12.70±5.06 and 12.50±2.71 years at final follow-up, the mean follow-up periods from IOL implantation were 94.93±24.22 and 109.09±18.89 months, and the mean BCVA (Log MAR) values were 0.51±0.37 and 1.05±0.46, respectively. Final BCVA after secondary IOL implantation was significantly associated with laterality, type of cataract, age at primary cataract extraction, compliance with amblyopia therapy, and refractive correction after surgery. No significant associations were found between BCVA and sex, age at secondary IOL implantation, VAO, or other ocular complications. The most common ocular complications were VAO and elevated intraocular pressure after surgery. There were no other complications, with the exception of one eye with IOL dislocation. Conclusions The results indicate that the important determinants of long-term visual outcomes in children with congenital cataracts undergoing secondary IOL implantation are laterality, cataract type, age at initial cataract extraction, compliance with amblyopia therapy, and refractive error. PMID:26230501

Visual discrimination following partial telencephalic ablations in nurse sharks (Ginglymostoma cirratum).

PubMed

Graeber, R C; Schroeder, D M; Jane, J A; Ebbesson, S O

1978-07-15

An instrumental conditioning task was used to examine the role of the nurse shark telencephalon in black-white (BW) and horizontal-vertical stripes (HV) discrimination performance. In the first experiment, subjects initially received either bilateral anterior telencephalic control lesions or bilateral posterior telencephalic lesions aimed at destroying the central telencephalic nuclei (CN), which are known to receive direct input from the thalamic visual area. Postoperatively, the sharks were trained first on BW and then on HV. Those with anterior lesions learned both tasks as rapidly as unoperated subjects. Those with posterior lesions exhibited visual discrimination deficits related to the amount of damage to the CN and its connecting pathways. Severe damage resulted in an inability to learn either task but caused no impairments in motivation or general learning ability. In the second experiment, the sharks were first trained on BW and HV and then operated. Suction ablations were used to remove various portions of the CN. Sharks with 10% or less damage to the CN retained the preoperatively acquired discriminations almost perfectly. Those with 11-50% damage had to be retrained on both tasks. Almost total removal of the CN produced behavioral indications of blindness along with an inability to perform above the chance level on BW despite excellent retention of both discriminations over a 28-day period before surgery. It appears, however, that such sharks can still detect light. These results implicate the central telencephalic nuclei in the control of visually guided behavior in sharks.

Cortical networks involved in visual awareness independent of visual attention.

PubMed

Webb, Taylor W; Igelström, Kajsa M; Schurger, Aaron; Graziano, Michael S A

2016-11-29

It is now well established that visual attention, as measured with standard spatial attention tasks, and visual awareness, as measured by report, can be dissociated. It is possible to attend to a stimulus with no reported awareness of the stimulus. We used a behavioral paradigm in which people were aware of a stimulus in one condition and unaware of it in another condition, but the stimulus drew a similar amount of spatial attention in both conditions. The paradigm allowed us to test for brain regions active in association with awareness independent of level of attention. Participants performed the task in an MRI scanner. We looked for brain regions that were more active in the aware than the unaware trials. The largest cluster of activity was obtained in the temporoparietal junction (TPJ) bilaterally. Local independent component analysis (ICA) revealed that this activity contained three distinct, but overlapping, components: a bilateral, anterior component; a left dorsal component; and a right dorsal component. These components had brain-wide functional connectivity that partially overlapped the ventral attention network and the frontoparietal control network. In contrast, no significant activity in association with awareness was found in the banks of the intraparietal sulcus, a region connected to the dorsal attention network and traditionally associated with attention control. These results show the importance of separating awareness and attention when testing for cortical substrates. They are also consistent with a recent proposal that awareness is associated with ventral attention areas, especially in the TPJ.

Modulation of brain activity by multiple lexical and word form variables in visual word recognition: A parametric fMRI study.

PubMed

Hauk, Olaf; Davis, Matthew H; Pulvermüller, Friedemann

2008-09-01

Psycholinguistic research has documented a range of variables that influence visual word recognition performance. Many of these variables are highly intercorrelated. Most previous studies have used factorial designs, which do not exploit the full range of values available for continuous variables, and are prone to skewed stimulus selection as well as to effects of the baseline (e.g. when contrasting words with pseudowords). In our study, we used a parametric approach to study the effects of several psycholinguistic variables on brain activation. We focussed on the variable word frequency, which has been used in numerous previous behavioural, electrophysiological and neuroimaging studies, in order to investigate the neuronal network underlying visual word processing. Furthermore, we investigated the variable orthographic typicality as well as a combined variable for word length and orthographic neighbourhood size (N), for which neuroimaging results are still either scarce or inconsistent. Data were analysed using multiple linear regression analysis of event-related fMRI data acquired from 21 subjects in a silent reading paradigm. The frequency variable correlated negatively with activation in left fusiform gyrus, bilateral inferior frontal gyri and bilateral insulae, indicating that word frequency can affect multiple aspects of word processing. N correlated positively with brain activity in left and right middle temporal gyri as well as right inferior frontal gyrus. Thus, our analysis revealed multiple distinct brain areas involved in visual word processing within one data set.

European Starlings Are Capable of Discriminating Subtle Size Asymmetries in Paired Stimuli

ERIC Educational Resources Information Center

Swaddle, John P.; Johnson, Charles W.

2007-01-01

Small deviations from bilateral symmetry (fluctuating asymmetries) are cues to fitness differences in some animals. Therefore, researchers have considered whether animals use these small asymmetries as visual cues to determine appropriate behavioral responses (e.g., mate preferences). However, there have been few systematic studies of animals'…

Comparison of visual outcomes after bilateral implantation of a diffractive trifocal intraocular lens and blended implantation of an extended depth of focus intraocular lens with a diffractive bifocal intraocular lens

PubMed Central

de Medeiros, André Lins; de Araújo Rolim, André Gustavo; Motta, Antonio Francisco Pimenta; Ventura, Bruna Vieira; Vilar, César; Chaves, Mário Augusto Pereira Dias; Carricondo, Pedro Carlos; Hida, Wilson Takashi

2017-01-01

Purpose The purpose of this study was to compare the visual outcomes and subjective visual quality between bilateral implantation of a diffractive trifocal intraocular lens, Alcon Acrysof IQ® PanOptix® TNFT00 (group A), and blended implantation of an extended depth of focus lens, J&J Tecnis Symfony® ZXR00 with a diffractive bifocal intraocular lens, J&J Vision Tecnis® ZMB00 (group B). Methods This prospective, nonrandomized, consecutive, comparative study included the assessment of 40 eyes in 20 patients implanted with multifocal intraocular lens. Exclusion criteria were existence of any corneal, retina, or optic nerve disease, previous eye surgery, illiteracy, previous refractive surgery, high axial myopia, expected postoperative corneal astigmatism of >1.00 cylindrical diopter (D), and intraoperative or postoperative complications. Binocular visual acuity was tested in all cases. Ophthalmological evaluation included the measurement of uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected near visual acuity (UNVA), and uncorrected intermediate visual acuity (UIVA), with the analysis of contrast sensitivity (CS), and visual defocus curve. Results Postoperative UDVA was 0.01 and −0.096 logMAR (p<0.01) in groups A and B, respectively; postoperative CDVA was −0.07 and −0.16 logMAR (p<0.01) in groups A and B, respectively; UIVA was 0.14 and 0.20 logMAR (p<0.01) in groups A and B, respectively; UNVA was −0.03 and 0.11 logMAR (p<0.01) in groups A and B, respectively. Under photopic conditions group B had better CS at low frequencies with and without glare. Conclusion Both groups promoted good quality of vision for long, intermediate, and short distances. Group B exhibited a better performance for very short distances and for intermediate and long distances ≥−1.50 D of vergence. Group A exhibited a better performance for UIVA at 60 cm and for UNVA at 40 cm. PMID:29138533

Electrophysiological evidence of altered visual processing in adults who experienced visual deprivation during infancy.

PubMed

Segalowitz, Sidney J; Sternin, Avital; Lewis, Terri L; Dywan, Jane; Maurer, Daphne

2017-04-01

We examined the role of early visual input in visual system development by testing adults who had been born with dense bilateral cataracts that blocked all patterned visual input during infancy until the cataractous lenses were removed surgically and the eyes fitted with compensatory contact lenses. Patients viewed checkerboards and textures to explore early processing regions (V1, V2), Glass patterns to examine global form processing (V4), and moving stimuli to explore global motion processing (V5). Patients' ERPs differed from those of controls in that (1) the V1 component was much smaller for all but the simplest stimuli and (2) extrastriate components did not differentiate amongst texture stimuli, Glass patterns, or motion stimuli. The results indicate that early visual deprivation contributes to permanent abnormalities at early and mid levels of visual processing, consistent with enduring behavioral deficits in the ability to process complex textures, global form, and global motion. © 2017 Wiley Periodicals, Inc.

Risk factors for amblyopia in the vision in preschoolers study.

PubMed

Pascual, Maisie; Huang, Jiayan; Maguire, Maureen G; Kulp, Marjean Taylor; Quinn, Graham E; Ciner, Elise; Cyert, Lynn A; Orel-Bixler, Deborah; Moore, Bruce; Ying, Gui-Shuang

2014-03-01

To evaluate risk factors for unilateral amblyopia and for bilateral amblyopia in the Vision in Preschoolers (VIP) study. Multicenter, cross-sectional study. Three- to 5-year-old Head Start preschoolers from 5 clinical centers, overrepresenting children with vision disorders. All children underwent comprehensive eye examinations, including threshold visual acuity (VA), cover testing, and cycloplegic retinoscopy, performed by VIP-certified optometrists and ophthalmologists who were experienced in providing care to children. Monocular threshold VA was tested using a single-surround HOTV letter protocol without correction, and retested with full cycloplegic correction when retest criteria were met. Unilateral amblyopia was defined as an interocular difference in best-corrected VA of 2 lines or more. Bilateral amblyopia was defined as best-corrected VA in each eye worse than 20/50 for 3-year-olds and worse than 20/40 for 4- to 5-year-olds. Risk of amblyopia was summarized by the odds ratios and their 95% confidence intervals estimated from logistic regression models. In this enriched sample of Head Start children (n = 3869), 296 children (7.7%) had unilateral amblyopia, and 144 children (3.7%) had bilateral amblyopia. Presence of strabismus (P<0.0001) and greater magnitude of significant refractive errors (myopia, hyperopia, astigmatism, and anisometropia; P<0.00001 for each) were associated independently with an increased risk of unilateral amblyopia. Presence of strabismus, hyperopia of 2.0 diopters (D) or more, astigmatism of 1.0 D or more, or anisometropia of 0.5 D or more were present in 91% of children with unilateral amblyopia. Greater magnitude of astigmatism (P<0.0001) and bilateral hyperopia (P<0.0001) were associated independently with increased risk of bilateral amblyopia. Bilateral hyperopia of 3.0 D or more or astigmatism of 1.0 D or more were present in 76% of children with bilateral amblyopia. Strabismus and significant refractive errors were risk factors for unilateral amblyopia. Bilateral astigmatism and bilateral hyperopia were risk factors for bilateral amblyopia. Despite differences in selection of the study population, these results validated the findings from the Multi-Ethnic Pediatric Eye Disease Study and Baltimore Pediatric Eye Disease Study. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Risk Factors for Amblyopia in the Vision In Preschoolers Study

PubMed Central

Pascual, Maisie; Huang, Jiayan; Maguire, Maureen G; Kulp, Marjean Taylor; Quinn, Graham E; Ciner, Elise; Cyert, Lynn A; Orel-Bixler, Deborah; Moore, Bruce; Ying, Gui-shuang

2013-01-01

Objective To evaluate risk factors for unilateral amblyopia and for bilateral amblyopia in the Vision In Preschoolers (VIP) Study. Design Multicenter, cross-sectional Study. Participants Three- to 5-year old Head Start preschoolers from 5 clinical centers, over-representing children with vision disorders. Methods All children underwent comprehensive eye exams including threshold visual acuity (VA), cover testing, and cycloplegic retinoscopy, performed by VIP-certified optometrists and ophthalmologists who were experienced in providing care to children. Monocular threshold VA was tested using single-surround HOTV letter protocol without correction, and retested with full cycloplegic correction when retest criteria were met. Unilateral amblyopia was defined as an inter-ocular difference in best-corrected VA ≥2 lines. Bilateral amblyopia was defined as best-corrected VA in each eye worse than 20/50 for 3-year-olds and worse than 20/40 for 4- to 5-year-olds. Main Outcome Measures Risk of amblyopia was summarized by The odds ratios (ORs) and their 95% confidence intervals (95% CIs) estimated from logistic regression models. Results In this enriched sample of Head Start children (N=3869), 296 (7.7%) children had unilateral amblyopia, and 144 (3.7%) children had bilateral amblyopia. Presence of strabismus (p<0.0001), greater magnitude of significant refractive errors (myopia, hyperopia, astigmatism, and anisometropia, each p<0.00001) were independently associated with increased risk of unilateral amblyopia. Presence of strabismus, hyperopia ≥2.0 D, astigmatism ≥1.0 D, or anisometropia ≥0.5 D were present in 91% of children with unilateral amblyopia. Greater magnitude of astigmatism (p<0.0001) and of bilateral hyperopia (p<0.0001) were independently associated with increased risk of bilateral amblyopia. Bilateral hyperopia ≥3.0 diopters (D) or astigmatism ≥1.0 D were present in 76% of children with bilateral amblyopia. Conclusion Strabismus and significant refractive errors were risk factors for unilateral amblyopia. Bilateral astigmatism and bilateral hyperopia were risk factors for bilateral amblyopia. Despite differences in selection of study population, these results validated the findings from the Multi-ethnic Pediatric Eye Disease Study and Baltimore Pediatric Eye Disease Study. PMID:24140117

Difference in glaucoma progression between the first and second eye after consecutive bilateral glaucoma surgery in patients with bilateral uveitic glaucoma.

PubMed

Din, Norshamsiah Md; Talat, Lazha; Isa, Hazlita; Tomkins-Netzer, Oren; Barton, Keith; Lightman, Sue

2016-12-01

To determine whether the second eyes (SE) of patients with bilateral uveitic glaucoma undergoing filtration surgery have more glaucomatous progression in terms of visual acuity, visual field (VF) and optic nerve changes compared to the first eyes (FE). This retrospective study analysed data of 60 eyes from 30 patients with bilateral uveitic glaucoma who had undergone glaucoma surgery in both eyes on separate occasions. Humphrey VF progression was assessed using the Progressor software. The pre-operative IOP between the FE (43.1 ± 7.7 mmHg) and SE (40 ± 8.7 mmHg) was not statistically significant (p = 0.15). IOP reduction was greater in the FE (64 %) than SE (59.7 %) post-operatively, but the mean IOP at the final visit in the FE (12.3 ± 3.9 mmHg) and SE (14.5 ± 7 mmHg) was not statistically different (p = 0.2). There was no significant change in mean logMAR readings pre and post-operatively (0.45 ± 0.6 vs 0.37 ± 0.6, p = 0.4) or between the FE and SE. The number of SE with CDR > 0.7 increased by 23 % compared to the FE. From 23 available VFs, five SE (21.7 %) progressed at a median of five locations (range 1-11 points) with a mean local slope reduction of 1.74 ± 0.45 dB/year (range -2.39 to -1.26), whereas only one FE progressed. However, there was no significant difference between mean global rate of progression between the FE (-0.9 ± 1.6 dB/year) and SE (-0.76 ± 2.1 dB/year, p = 0.17) in the Humphrey VF. In eyes with bilateral uveitic glaucoma requiring glaucoma surgery, the SEs had more progressed points on VF and glaucomatous disc progression compared to FEs at the final visit.

Visual field loss and accelerometer-measured physical activity in the United States.

PubMed

van Landingham, Suzanne W; Willis, Jeffrey R; Vitale, Susan; Ramulu, Pradeep Y

2012-12-01

To determine whether visual field (VF) loss is associated with lower levels of accelerometer-defined walking or physical activity in a nationally representative sample of American adults. Cross-sectional study. A total of 2934 adults aged 40 years or older who participated in the examination component of the 2005-2006 National Health and Nutritional Examination Survey. Frequency-doubling technology (FDT) testing was performed in both eyes and used to categorize subjects as having no VF loss, unilateral VF loss, or bilateral VF loss. Accelerometer data were collected over 7 days of normal activity. Steps per day and daily minutes of moderate or vigorous physical activity (MVPA). A total of 1468 participants (50.0%) had complete FDT and accelerometer data. Individuals without VF loss averaged 9751 steps/day and 20.8 minutes/day of MVPA, compared with 8023 steps/day and 14.5 minutes/day for subjects with unilateral VF loss (age-adjusted P = 0.11 and P = 0.51) and 6840 steps/day and 10.1 minutes/day for subjects with bilateral VF loss (age-adjusted P = 0.02 and 0.09, respectively). In multivariable models adjusted for age, sex, race/ethnicity, education, and several comorbid illnesses, individuals with bilateral VF loss took 17% fewer steps per day (P < 0.01) and engaged in 30% less MVPA (P = 0.02) than individuals without VF loss. No significant difference in steps per day or MVPA was observed between individuals with unilateral VF loss and no VF loss (P > 0.05). In addition to VF loss, older age, female sex, arthritis, diabetes, congestive heart failure (CHF), and stroke were significantly associated with fewer daily steps and minutes of MVPA (P < 0.05). Bilateral VF loss is associated with less walking and physical activity in American adults. Patients with bilateral VF loss should be encouraged to engage safely in more physical activity. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Prevelence and causes of visual impairment and blindness in older adults in an area of India with a high cataract surgical rate.

PubMed

Murthy, Gudlavalleti V S; Vashist, Praveen; John, Neena; Pokharel, Gopal; Ellwein, Leon B

2010-08-01

The cataract surgical rate (CSR) in Gujarat, India is reported to be above 10,000 per million population. This study was conducted to investigate the prevalence and causes of vision impairment/blindness among older adults in a high CSR area. Geographically defined cluster sampling was used in randomly selecting persons >or= 50 years of age in Navsari district. Subjects in 35 study clusters were enumerated and invited for measurement of presenting and best-corrected visual acuity and an ocular examination. The principal cause was identified for eyes with presenting visual acuity < 20/32. A total of 5158 eligible persons were enumerated and 4738 (91.9%) examined. Prevalence of presenting visual impairment < 20/63 to 20/200 in the better eye was 29.3% (95% confidence interval [CI]: 27.5-31.2) and 13.5% (95% CI: 12.0-14.9) with best correction. The prevalence of presenting bilateral blindness (< 20/200) was 6.9% (95% CI: 5.7-8.1), and 3.1% (95% CI: 2.5-3.7) with best correction. Presenting and best-corrected blindness were both associated with older age and illiteracy; gender and rural/urban residence were not significant. Cataract in one or both eyes was the main cause of bilateral blindness (82.6%), followed by retinal disorders (8.9%). Cataract (50.3%) and refractive error (35.4%) were the main causes in eyes with vision acuity < 20/63 to 20/200, and refractive error (86.6%) in eyes with acuity < 20/32 to 20/63. Visual impairment and blindness is a significant problem among the elderly in Gujarat. Despite a reportedly high CSR, cataract remains the predominant cause of blindness.

Frontoparietal tDCS Benefits Visual Working Memory in Older Adults With Low Working Memory Capacity.

PubMed

Arciniega, Hector; Gözenman, Filiz; Jones, Kevin T; Stephens, Jaclyn A; Berryhill, Marian E

2018-01-01

Working memory (WM) permits maintenance of information over brief delays and is an essential executive function. Unfortunately, WM is subject to age-related decline. Some evidence supports the use of transcranial direct current stimulation (tDCS) to improve visual WM. A gap in knowledge is an understanding of the mechanism characterizing these tDCS linked effects. To address this gap, we compared the effects of two tDCS montages designed on visual working memory (VWM) performance. The bifrontal montage was designed to stimulate the heightened bilateral frontal activity observed in aging adults. The unilateral frontoparietal montage was designed to stimulate activation patterns observed in young adults. Participants completed three sessions (bilateral frontal, right frontoparietal, sham) of anodal tDCS (20 min, 2 mA). During stimulation, participants performed a visual long-term memory (LTM) control task and a visual WM task. There was no effect of tDCS on the LTM task. Participants receiving right unilateral tDCS showed a WM benefit. This pattern was most robust in older adults with low WM capacity. To address the concern that the key difference between the two tDCS montages could be tDCS over the posterior parietal cortex (PPC), we included new analyses from a previous study applying tDCS targeting the PPC paired with a recognition VWM task. No significant main effects were found. A subsequent experiment in young adults found no significant effect of either tDCS montage on either task. These data indicate that tDCS montage, age and WM capacity should be considered when designing tDCS protocols. We interpret these findings as suggestive that protocols designed to restore more youthful patterns of brain activity are superior to those that compensate for age-related changes.

EOG as a monitor of desferrioxamine retinal toxicity.

PubMed

Hidajat, Rudy R; McLay, Jan L; Goode, David H; Spearing, Ruth L

2004-11-01

Iron overload caused by blood transfusion-dependent anaemia usually results in lethal cardiac toxicity unless treated by iron-chelation therapy. Chelation therapy with desferrioxamine (DFO) is well established and widely used to remove excess iron. Unfortunately, visual disorders have been recorded after DFO infusion. In this investigation, a 61-year-old Caucasian female received DFO for her autoimmune haemolytic anaemia. Prior to starting with the DFO treatment, her baseline ophthalmic screening and electrooculogram (EOG) were completely normal. Two years later she noticed a grey scotoma in her right eye. Visual acuity in this eye was reduced from 6/5 to 6/9 and funduscopy revealed evidence of non-specific mottling of the retinal pigment epithelium of both retinae. The EOG was flat (106%) in the right eye and subnormal in the left (155%). The lower limit of our EOG Arden Ratio for normal subjects is 180%. After her DFO treatment was stopped, her right visual acuity returned to 6/5, her field tests showed progressive improvement bilaterally and the EOG went back to the normal range. While waiting for splenectomy, the patient was restarted on a lower dose of DFO and EOG measurements were carried out every two (or three) weeks to monitor for DFO toxicity. The EOG varied during this period indicating some deterioration of function in the retinal pigment epithelium. However, normalisation of the EOG values (right = 217%, left = 217%) occurred after splenectomy and cessation of DFO therapy. Her visual function was normal and her visual acuity 6/4 bilateral when she was discharged from our outpatient clinic. On reviewing her history it was apparent that the EOG was the most sensitive indicator of DFO toxicity.

Visual performance after bilateral implantation of 2 new presbyopia-correcting intraocular lenses: Trifocal versus extended range of vision.

PubMed

Monaco, Gaspare; Gari, Mariangela; Di Censo, Fabio; Poscia, Andrea; Ruggi, Giada; Scialdone, Antonio

2017-06-01

To compare the visual outcomes and quality of vision of 2 new diffractive multifocal intraocular lenses (IOLs) with those of a monofocal IOL. Fatebenefratelli e Oftalmico Hospital, Milan, Italy. Prospective case series. Patients had bilateral cataract surgery with implantation of a trifocal IOL (Panoptix), an extended-range-of-vision IOL (Symfony), or a monofocal IOL (SN60WF). Postoperative examinations included assessing distance, intermediate, and near visual acuity; binocular defocus; intraocular and total aberrations; point-spread function (PSF); modulation transfer function (MTF); retinal straylight; and quality-of-vision (QoV) and spectacle-dependence questionnaires. Seventy-six patients (152 eyes) were assessed for study eligibility. Twenty patients (40 eyes) in each arm of the study (60 patients, 120 eyes) completed the outcome assessment. At the 4-month follow-up, the trifocal group had significantly better near visual acuity than the extended-range-of-vision group (P = .005). The defocus curve showed the trifocal IOL had better intermediate/near performance than the extended-range-of-vision IOL and both multifocal IOLs performed better than the monofocal IOL. Intragroup comparison of the total higher-order aberrations, PSF, MTF, and retinal straylight were not statistically different. The QoV questionnaire results showed no differences in dysphotopsia between the multifocal IOL groups; however, the results were significantly higher than in the monofocal IOL group. Both multifocal IOLs seemed to be good options for patients with intermediate-vision requirements, whereas the trifocal IOL might be better for patients with near-vision requirements. The significant perception of visual side effects indicates that patients still must be counseled about these effects before a multifocal IOL is implanted. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Prevalence and causes of low vision and blindness in an elderly population in Nepal: the Bhaktapur retina study.

PubMed

Thapa, Raba; Bajimaya, Sanyam; Paudyal, Govinda; Khanal, Shankar; Tan, Stevie; Thapa, Suman S; van Rens, G H M B

2018-02-13

This study aims to explore the prevalence and causes of low vision and blindness focused on retinal disease in a population above 60 years in Nepal. Two thousand one hundred subjects were enrolled in a population-based cross-sectional study. History, presenting and best corrected visual acuity after subjective refraction, anterior and posterior segment examinations was obtained in detail. Among the total subjects, 1860 (88.57%) had complete information. Age varies from 60 to 95 (mean age: 69.64 ± 7.31) years. Low vision and blindness in both eyes at presentation was found in 984 (52.90%, 95% confidence interval (CI): 50.60-55.19) and 36 (1.94%, 95% CI: 1.35-2.66) subjects respectively. After best correction, bilateral low vision and blindness was found in 426 (22.92%, 95% CI: 21.01-24.88), and 30 (1.61%, 95% CI: 0.10-2.30) subjects respectively. As compared to 60-69 years old, risk of visual impairment was four times higher (95% CI:3.26-5.58) in the 70-79 year olds and 14 times higher (95% CI: 9.72-19.73) in the age group 80 years and above. Major causes of bilateral low vision were cataract (68.07%), followed by retinal disorders (28.64%), and for blindness; retinal disorders (46.66%), followed by cataract (43.33%). Illiteracy was significantly associated with visual impairment. Among the elderly population, prevalence of visual impairment was high. Refractive error, cataract and retinal disorders were the major cause of low vision. Screening the population at the age 60 years and above, focused on cataract and posterior segment diseases, providing glasses and timely referral can help reduce visual impairment.

Visual perceptual training reconfigures post-task resting-state functional connectivity with a feature-representation region.

PubMed

Sarabi, Mitra Taghizadeh; Aoki, Ryuta; Tsumura, Kaho; Keerativittayayut, Ruedeerat; Jimura, Koji; Nakahara, Kiyoshi

2018-01-01

The neural mechanisms underlying visual perceptual learning (VPL) have typically been studied by examining changes in task-related brain activation after training. However, the relationship between post-task "offline" processes and VPL remains unclear. The present study examined this question by obtaining resting-state functional magnetic resonance imaging (fMRI) scans of human brains before and after a task-fMRI session involving visual perceptual training. During the task-fMRI session, participants performed a motion coherence discrimination task in which they judged the direction of moving dots with a coherence level that varied between trials (20, 40, and 80%). We found that stimulus-induced activation increased with motion coherence in the middle temporal cortex (MT+), a feature-specific region representing visual motion. On the other hand, stimulus-induced activation decreased with motion coherence in the dorsal anterior cingulate cortex (dACC) and bilateral insula, regions involved in decision making under perceptual ambiguity. Moreover, by comparing pre-task and post-task rest periods, we revealed that resting-state functional connectivity (rs-FC) with the MT+ was significantly increased after training in widespread cortical regions including the bilateral sensorimotor and temporal cortices. In contrast, rs-FC with the MT+ was significantly decreased in subcortical regions including the thalamus and putamen. Importantly, the training-induced change in rs-FC was observed only with the MT+, but not with the dACC or insula. Thus, our findings suggest that perceptual training induces plastic changes in offline functional connectivity specifically in brain regions representing the trained visual feature, emphasising the distinct roles of feature-representation regions and decision-related regions in VPL.

Enhanced visualization of acute macular neuroretinopathy by Heidelberg Retina Tomography.

PubMed

Mirshahi, Alireza; Scharioth, Gàbor B; Klais, Christina M C; Baatz, Holger

2006-08-01

We report Heidelberg Retina Tomography (HRT) findings in a case of bilateral acute macular neuroretinopathy in a 22-year-old man. In addition to fundus photography, fluorescein and indocyanine green angiography, and visual field testing, HRT scans of the macula were performed early in the disease and at a follow up of 2 months. We found typical paracentral scotomata in visual field testing corresponding to sharply delineated, hyporeflective areas of the macula as visualized in HRT II scans. Those lesions were almost invisible on regular fundus photographs. Angiography results were unremarkable. The lesion size decreased over time. The visibility of the lesions was markedly enhanced by HRT scans, thus the diagnosis and follow up of acute macular neuroretinopathy could be facilitated by this non-invasive imaging technique.

Cerebral venous hypertension and blindness: a reversible complication.

PubMed

Cuadra, Salvador A; Padberg, Frank T; Turbin, Roger E; Farkas, Jeffrey; Frohman, Larry P

2005-10-01

A 57-year-old woman developed blindness during treatment for sarcoidosis-induced end-stage renal disease. An initial renal transplantation failed, and hemoaccess was maintained with multiple central catheters and upper extremity prosthetic arteriovenous grafts. A successful second transplantation eliminated her need for hemodialysis, but a right brachial to internal jugular graft remained patent. Progressive visual loss 2 years after transplantation prompted ophthalmic evaluation which initially revealed unilateral left optic nerve edema and visual loss, ultimately worsening over several months to no light perception in the left eye, 20/60 vision in the right eye, and bilateral papilledema. Arteriography demonstrated cerebral venous hypertension attributed to the functioning hemoaccess graft. Permanent graft occlusion normalized the papilledema, and visual field defects in the right eye and visual acuity returned to 20/20 in the right eye.

Translation, cultural adaptation and validation of Kidney Disease Loss Scale to the Brazilian context.

PubMed

Ottaviani, Ana Carolina; Orlandi, Fabiana de Souza

2016-01-01

Losses can be conceptualized as cognitive and affective responses to individual sorrows, characterized by brooding, yearning, disbelief and stunned feelings, being clinically significant in chronic diseases. The aim of the study was to translate, culturally adapt and validate the Kidney Disease Loss Scale into Portuguese. Validation study involving the steps recommended in the literature for healthcare instruments: initial translation, synthesis of translations, back translation, review by a committee of judges and pretest. The scale was translated and adapted to the Portuguese language, being quick and easy to application. The reliability and reproducibility showed satisfactory values. Factor analysis indicated a factor that explains 59.7% of the losses construct. The Kidney Disease Loss Scale was translated, adapted and validated for the Brazilian context, allowing future studies of losses and providing tools for the professionals working in dialysis centers for assistance to people with chronic kidney disease. As perdas podem ser conceituadas como respostas cognitivas e afetivas para tristezas individuais, caracterizadas pelo remoer, anseio, descrença e sentimentos atordoados, sendo clinicamente significativa em doenças crônicas. O objetivo do estudo foi traduzir, adaptar culturalmente e validar o Kidney Disease Loss Scale para a língua portuguesa. Estudo de validação envolveu as etapas preconizadas na literatura internacional para instrumentos da área de saúde: tradução inicial, síntese das traduções, retrotradução, revisão por um comitê de juízes, pré-teste e avaliação das propriedades psicométricas. A escala foi traduzida e adaptada para o idioma português, sendo de fácil e rápida aplicação. A confiabilidade e a reprodutibilidade apresentaram valores satisfatórios. A análise fatorial indicou um fator que explica 59,7% do constructo de perdas. A Escala de Perdas referente à Doença Renal foi traduzida, adaptada e validada para o contexto brasileiro, permitindo estudos futuros sobre perdas e instrumentalizando os profissionais atuantes em centros de diálise para assistência à pessoa com doença renal crônica.

Exploding Head Syndrome as Aura of Migraine with Brainstem Aura: A Case Report.

PubMed

Rossi, Fabian H; Gonzalez, Elizabeth; Rossi, Elisa Marie; Tsakadze, Nina

2018-01-01

This article reports a case of exploding head syndrome (EHS) as an aura of migraine with brainstem aura (MBA). A middle-aged man presented with intermittent episodes of a brief sensation of explosion in the head, visual flashing, vertigo, hearing loss, tinnitus, confusion, ataxia, dysarthria, and bilateral visual impairment followed by migraine headache. The condition was diagnosed as MBA. Explosive head sensation, sensory phenomena, and headaches improved over time with nortriptyline. This case shows that EHS can present as a primary aura symptom in patients with MBA.

Similarities in neural activations of face and Chinese character discrimination.

PubMed

Liu, Jiangang; Tian, Jie; Li, Jun; Gong, Qiyong; Lee, Kang

2009-02-18

This study compared Chinese participants' visual discrimination of Chinese faces with that of Chinese characters, which are highly similar to faces on a variety of dimensions. Both Chinese faces and characters activated the bilateral middle fusiform with high levels of correlations. These findings suggest that although the expertise systems for faces and written symbols are known to be anatomically differentiated at the later stages of processing to serve face processing or written-symbol-specific processing purposes, they may share similar neural structures in the ventral occipitotemporal cortex at the stages of visual processing.

Vaginoscopy compared to traditional hysteroscopy for hysteroscopic sterilization. A randomized trial.

PubMed

Chapa, Hector O; Venegas, Gonzalo

2015-01-01

To compare vaginoscopic hysteroscopic sterilization with traditional hysteroscopic approach for differences in pain, bilateral microinsert placement rates, and procedure time. We performed a prospective, randomized, single-blinded study of hysteroscopic sterilization using the Essure System. The study setting was an inner city ObGyn clinic. Ninety patients were randomized to either vaginoscopy or traditional approach. The traditional approach was speculum insertion, paracervical analgesia, and tenaculum. All procedures were done with a 5 mm, 30 degree rigid hysteroscope. Main outcome measures were pain scores (10-point visual analog scale), bilateral placement rates, and procedure times. Vaginoscopy was successful in 42/45 patients (93%). There was no statistically significant difference in pain-scores for microinsert placement between the groups (p = 0.71). First attempt, bilateral microinsert placement rate was 95% (40/42) with vaginoscopy and 95% (43/45) with traditional (p = 0.89). Time for treatment completion was 16 minutes (mean) (range, 13-21) in the traditional group versus vaginoscopy time of 9 minutes (mean) (range, 7-11) (p = 0.03). Hysteroscopic sterilization via vaginoscopy is feasible with bilateral microinsert rates comparable to those of traditional hysteroscopy. Vaginoscopy is associated with less overall discomfort and is faster to perform.

Bilateral vision loss in a captive cheetah (Acinonyx jubatus).

PubMed

Walser-Reinhardt, Ladina; Wernick, Morena B; Hatt, Jean-Michel; Spiess, Bernhard M

2010-09-01

The following case report describes a 1-year-old female cheetah (Acinonyx jubatus) with bilateral blindness and unresponsive pupils. For comparison, a second healthy 2.5-year-old male cheetah without visual deficits was also examined. Clinical examination of both animals included biomicroscopy, indirect ophthalmoscopy, tonometry, and electroretinography. The young female cheetah showed no menace response, no direct or indirect pupillary light reflex, and no dazzle reflex in either eye. Fundus lesions, as detected by indirect ophthalmoscopy, are described for the female animal. In both eyes, the fundus color was green/turquoise/yellow with multiple hyperpigmented linear lesions in the tapetal area around the optic nerve. The optic nerve head was dark gray and about half the normal size suggesting bilateral optic nerve hypoplasia and retinal dysplasia or differentially optic nerve atrophy and chorioretinal scarring. The ERG had low amplitudes in the right eye but appeared normal in the left eye compared with the male cheetah. Blood levels did not suggest current taurine deficiency. This is addressed to some degree in the discussion. Bilateral optic nerve hypoplasia or optic nerve atrophy is a rare anomaly in cats and has not yet been described in a cheetah.

Visual Dysfunction in Posterior Cortical Atrophy

PubMed Central

Maia da Silva, Mari N.; Millington, Rebecca S.; Bridge, Holly; James-Galton, Merle; Plant, Gordon T.

2017-01-01

Posterior cortical atrophy (PCA) is a syndromic diagnosis. It is characterized by progressive impairment of higher (cortical) visual function with imaging evidence of degeneration affecting the occipital, parietal, and posterior temporal lobes bilaterally. Most cases will prove to have Alzheimer pathology. The aim of this review is to summarize the development of the concept of this disorder since it was first introduced. A critical discussion of the evolving diagnostic criteria is presented and the differential diagnosis with regard to the underlying pathology is reviewed. Emphasis is given to the visual dysfunction that defines the disorder, and the classical deficits, such as simultanagnosia and visual agnosia, as well as the more recently recognized visual field defects, are reviewed, along with the evidence on their neural correlates. The latest developments on the imaging of PCA are summarized, with special attention to its role on the differential diagnosis with related conditions. PMID:28861031

Interface Fluid Syndrome After Laser In Situ Keratomileusis (LASIK) Because of Fuchs Endothelial Dystrophy Reversed by Descemet Membrane Endothelial Keratoplasty (DMEK).

PubMed

Luceri, Salvatore; Baksoellah, Zainab; Ilyas, Abbas; Baydoun, Lamis; Melles, Gerrit R J

2016-12-01

To describe a case that developed "interface fluid syndrome" after previous laser in situ keratomileusis (LASIK) because of Fuchs endothelial dystrophy (FED), which was reversed by Descemet membrane endothelial keratoplasty (DMEK). A 58-year-old male patient presented with bilateral visual impairment owing to FED and visually significant cataract. Cataract surgery was carried out in both eyes followed by DMEK in his left eye. After cataract surgery, visual acuity did not improve sufficiently because corneal thickness increased and a fine cleft with interface fluid developed between the LASIK-flap and the residual stromal bed. After uneventful DMEK in his left eye, the fluid resolved within a week and visual acuity improved rapidly. This case demonstrates that "interface fluid syndrome" after LASIK caused by concomitant endothelial dysfunction may be reversed by DMEK allowing fast visual recovery.

Change in the accommodative convergence per unit of accommodation ratio after bilateral laser in situ keratomileusis for myopia in orthotropic patients: prospective evaluation.

PubMed

Prakash, Gaurav; Choudhary, Vandana; Sharma, Namrata; Titiyal, Jeewan S

2007-12-01

To analyze the effect of bilateral laser in situ keratomileusis (LASIK) on the accommodative convergence per unit of accommodation (AC/A) ratio in otherwise normal orthotropic myopic patients. Cornea and refractive services of a tertiary-care ophthalmic center. This prospective clinical trial consisted of 61 myopic patients who had bilateral LASIK. Those with manifest tropia, previous squint surgery, amblyopia, or absent or impaired binocularity or those in whom monovision was planned were excluded. The preoperative examination included visual acuity, cycloplegic refraction, assessment of binocularity, a prism cover test, and evaluation of the stimulus AC/A ratio by the gradient method. All patients had LASIK using the Zyoptix platform (Bausch & Lomb). Postoperative evaluation included uncorrected and best corrected visual acuities, residual refraction, and the AC/A ratio. All patients had a follow-up of 9 months. There was significant decrease in the mean AC/A ratio at the 1-week and 1-month follow-ups. The AC/A progressively recovered to near preoperative values between 3 months and 9 months after surgery (analysis of variance test). There was a significant reduction in the number of symptomatic patients from the first month onward (chi square = 89.23; P<.001). The AC/A ratio varied after LASIK, stabilizing between 3 months and 9 months after surgery. This suggests that the maximum variation in the accommodation-convergence relationship after LASIK occurs in the first 3 months.

Monkey’s short-term auditory memory nearly abolished by combined removal of the rostral superior temporal gyrus and rhinal cortices

PubMed Central

Fritz, Jonathan B.; Malloy, Megan; Mishkin, Mortimer; Saunders, Richard C.

2016-01-01

While monkeys easily acquire the rules for performing visual and tactile delayed matching-to-sample, a method for testing recognition memory, they have extraordinary difficulty acquiring a similar rule in audition. Another striking difference between the modalities is that whereas bilateral ablation of the rhinal cortex (RhC) leads to profound impairment in visual and tactile recognition, the same lesion has no detectable effect on auditory recognition memory (Fritz et al., 2005). In our previous study, a mild impairment in auditory memory was obtained following bilateral ablation of the entire medial temporal lobe (MTL), including the RhC, and an equally mild effect was observed after bilateral ablation of the auditory cortical areas in the rostral superior temporal gyrus (rSTG). In order to test the hypothesis that each of these mild impairments was due to partial disconnection of acoustic input to a common target (e.g., the ventromedial prefrontal cortex), in the current study we examined the effects of a more complete auditory disconnection of this common target by combining the removals of both the rSTG and the MTL. We found that the combined lesion led to forgetting thresholds (performance at 75% accuracy) that fell precipitously from the normal retention duration of ~30–40 seconds to a duration of ~1–2 seconds, thus nearly abolishing auditory recognition memory, and leaving behind only a residual echoic memory. PMID:26707975

Acute optic neuropathy associated with a novel MFN2 mutation.

PubMed

Leonardi, Luca; Marcotulli, Christian; Storti, Eugenia; Tessa, Alessandra; Serrao, Mariano; Parisi, Vincenzo; Santorelli, F M; Pierelli, Francesco; Casali, Carlo

2015-07-01

Mutations in the mitofusin 2 (MFN2) gene cause CMT2A the most common form of autosomal dominant axonal Charcot-Marie-Tooth (CMT). In addition, mutations in MFN2 have been shown to be responsible for Hereditary Motor Sensory Neuropathy type VI (HSMN VI), a rare early-onset axonal CMT associated with optic neuropathy. Most reports of HMSN VI presented with a sub-acute form of optic neuropathy. Herein, we report a CMT2A patient, who developed very rapidly progressing severe optic neuropathy. A 40-year-old Caucasian man was evaluated for gait disturbance and lower limbs weakness, slowly progressed over the last 2 years. Due to clinical data and family history, a diagnosis of CMT2 was made. The novel heterozygous c.775C > T (p.Arg259Cys) mutation in MFN2 was detected in the patient and his clinical affected mother. Interestingly, the patient developed a severe sudden bilateral visual deterioration few years early, with clinical and instrumental picture suggestive of acute bilateral optic neuropathy. Our report expands the spectrum of MFN2-related manifestation because it indicates that visual symptoms of HMSN VI may enter in the differential with acquired or hereditary acute optic neuropathies, and that severe optic neuropathy is not invariably an early manifestation of the disease but may occur as disease progressed. This report could have an impact on clinicians who evaluate patients with otherwise unexplainable bilateral acute-onset optic neuropathy, especially if associated with a motor and sensory axonal neuropathy.

Brain MRI findings in acute hepatic encephalopathy in liver transplant recipients.

PubMed

Guo, Ruo-Mi; Li, Qing-Ling; Zhong, Li-Ru; Guo, Yu; Jiao, Ju; Chen, Shao-Qiong; Wang, Jin; Zhang, Yong

2018-06-01

Acute hepatic encephalopathy has significant morbidity and mortality in liver transplant recipients unless it is promptly treated. We evaluated the brain magnetic resonance (MR) imaging findings associated with acute hepatic encephalopathy in transplant recipients. We retrospectively reviewed the clinical and imaging data and outcomes of twenty-five liver transplant patients (16 male; mean age, 49.3 years) with clinically diagnosed acute hepatic encephalopathy and forty liver transplant patients (20 males; mean age, 45.5 years) without neurological symptoms suggestive of hepatic encephalopathy at our institution. Bilateral symmetric hyperintensities of the insular cortex and cingulate gyrus were observed in twenty-one patients (84.00%), bilateral symmetric extensive increased cortical signal intensity (involving two or more regions) was observed in 72.00% of the patients, leptomeningeal enhancement in 73.68%, and visualization of prominent venules in 52.00%. The most common symptom at diagnosis was rigidity (n = 14), and the plasma ammonia levels ranged from 68.63 to 192.16 μmol/L. After active treatment, 17 patients gradually recovered, four patients suffered from mild or moderate neurologic deficits, and four patients with widespread brain edema died. The specific brain MR imaging features were bilateral symmetric increased cortical signal intensity, especially in the insular cortex and cingulate gyrus, leptomeningeal enhancement, visualization of the prominent venules, and widespread brain edema. These features may indicate poor prognosis and should alert radiologists to the possibility of acute hepatic encephalopathy in liver transplant recipients and encourage clinicians to prepare appropriate treatment in advance.

Ultra-fast speech comprehension in blind subjects engages primary visual cortex, fusiform gyrus, and pulvinar – a functional magnetic resonance imaging (fMRI) study

PubMed Central

2013-01-01

Background Individuals suffering from vision loss of a peripheral origin may learn to understand spoken language at a rate of up to about 22 syllables (syl) per second - exceeding by far the maximum performance level of normal-sighted listeners (ca. 8 syl/s). To further elucidate the brain mechanisms underlying this extraordinary skill, functional magnetic resonance imaging (fMRI) was performed in blind subjects of varying ultra-fast speech comprehension capabilities and sighted individuals while listening to sentence utterances of a moderately fast (8 syl/s) or ultra-fast (16 syl/s) syllabic rate. Results Besides left inferior frontal gyrus (IFG), bilateral posterior superior temporal sulcus (pSTS) and left supplementary motor area (SMA), blind people highly proficient in ultra-fast speech perception showed significant hemodynamic activation of right-hemispheric primary visual cortex (V1), contralateral fusiform gyrus (FG), and bilateral pulvinar (Pv). Conclusions Presumably, FG supports the left-hemispheric perisylvian “language network”, i.e., IFG and superior temporal lobe, during the (segmental) sequencing of verbal utterances whereas the collaboration of bilateral pulvinar, right auditory cortex, and ipsilateral V1 implements a signal-driven timing mechanism related to syllabic (suprasegmental) modulation of the speech signal. These data structures, conveyed via left SMA to the perisylvian “language zones”, might facilitate – under time-critical conditions – the consolidation of linguistic information at the level of verbal working memory. PMID:23879896

Sex differences in functional activation patterns revealed by increased emotion processing demands.

PubMed

Hall, Geoffrey B C; Witelson, Sandra F; Szechtman, Henry; Nahmias, Claude

2004-02-09

Two [O(15)] PET studies assessed sex differences regional brain activation in the recognition of emotional stimuli. Study I revealed that the recognition of emotion in visual faces resulted in bilateral frontal activation in women, and unilateral right-sided activation in men. In study II, the complexity of the emotional face task was increased through tje addition of associated auditory emotional stimuli. Men again showed unilateral frontal activation, in this case to the left; whereas women did not show bilateral frontal activation, but showed greater limbic activity. These results suggest that when processing broader cross-modal emotional stimuli, men engage more in associative cognitive strategies while women draw more on primary emotional references.

Bilateral adrenal histoplasmosis: endoscopic ultrasound-guided fine needle aspiration as a method of diagnosis and assessment.

PubMed

Azhar, J Khairul; Jacqueline, H S G; Tony, L K H; Tan, B H; Steven, J M

2011-12-01

We report a case of a healthy 78-year-old indonesian man who presented with chronic weight loss, poor appetite and lethargy. CT abdomen showed bilateral adrenal masses. EUS-guided FNA was performed on the left adrenal gland. Histopathology report was Histoplasma Capsulatum. He recovered well with antifungal treatment without any complication. In this case, we found that the role of EUS -guided FNA was not only limited to diagnosis but also helped in the prognosis of the disease since the method was able to assess the general anatomy of the adrenal gland better than other imaging modalities due to its close proximity and direct visualization.

Optic neuritis in pediatric population: a review in current tendencies of diagnosis and management.

PubMed

Pérez-Cambrodí, Rafael José; Gómez-Hurtado Cubillana, Aránzazu; Merino-Suárez, María L; Piñero-Llorens, David P; Laria-Ochaita, Carlos

2014-01-01

Optic neuritis is an inflammation of the optic nerve and may be related to different systemic conditions. The clinical presentation of this pathology usually includes sudden loss of visual acuity (VA) which may be unilateral or bilateral, visual field restriction, pain with eye movements, dyschromatopsia, a relative afferent pupillary defect and optic disk swelling. Optic neuritis in children has specific clinical features and a better prognosis than in adulthood. Although usually appears an underlying viral disease, the main concern for practitioners is the relationship of optic neuritis with multiple sclerosis. In addition to the classical techniques as magnetic resonance imaging (MRI), current tendencies of diagnosis for eye practitioners include new imaging devices as optical coherence tomography (OCT), useful to show a thinning of the retinal fibers layer (RFL) after the inflammatory episode. Regarding the management of these patients, short-term intravenous steroid dosages seem to be the best option to treat acute attacks characterized by a very poor bilateral VA. Copyright © 2013 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

Direction discrimination learning in normal and visually deprived cats and the effects of lateral suprasylvian lesions.

PubMed

Burnat, K; Zernicki, B

1997-01-01

We used 5 binocularly deprived cats (BD cats), 4 control cats reared also in the laboratory (C cats) and 4 cats reared in a normal environment (N cats). The cats were trained to discriminate an upward or downward-moving light spot versus a stationary spot (detection task) and then an upward versus a downward spot (direction task). The N and C cats learned slowly. The learning was slower than in previously studied discriminations of stationary stimuli. However, all N and C cats mastered the detection task and except one C cat the direction task. In contrast, 4 BD cats failed in the detection task and all in the direction task. This result is consistent with single-cell recording data showing impairment of direction analysis in the visual system in BD cats. After completing the training the upper part of the middle suprasylvian sulcus was removed unilaterally in 7 cats and bilaterally in 6 cats. Surprisingly, the unilateral lesions were more effective: the clear-cut retention deficits were found in 5 cats lesioned unilaterally, whereas only in one cat lesioned bilaterally.

Bilateral chorioretinal coloboma discovered with ultra-wide field retinal imaging

PubMed Central

Barnard, Simon; Shneor, Einat; Brauner, Joel; Millodot, Michel; Gordon-Shaag, Ariela

2012-01-01

Uveal coloboma results from incomplete closure of the optic cup fissure. While conducting an evaluation of a new ultra-wide field retinal imaging camera (Optomap), which provides a view of the fundus up to 200° at one time without mydriasis, we discovered a case of bilateral chorioretinal coloboma in a 21-year-old student. The lesion was located in the midperiphery of each eye less than 2 disc diameters (DD) below the optic disc in the inferonasal quadrants. The size of the coloboma in the right eye was 1.8 DD in height and 1.3 DD in width, while the left lesion was 2.4 DD in height and 2.6 DD in width. The subject was totally asymptomatic and without any complication such as retinal detachment or choroidal neovascularization, which often accompany this type of lesion. The visual field of each eye displayed an absolute scotoma corresponding to the size and location of the coloboma. No management was necessary but the subject was advised to report for visual examination at regular intervals because complications can occur at any age.

Reduced functional connectivity between V1 and inferior frontal cortex associated with visuomotor performance in autism

PubMed Central

Villalobos, Michele E.; Mizuno, Akiko; Dahl, Branelle C.; Kemmotsu, Nobuko; Müller, Ralph-Axel

2010-01-01

Some recent evidence has suggested abnormalities of the dorsal stream and possibly the mirror neuron system in autism, which may be responsible for impairments of joint attention, imitation, and secondarily for language delays. The current study investigates functional connectivity along the dorsal stream in autism, examining interregional blood oxygenation level dependent (BOLD) signal cross-correlation during visuomotor coordination. Eight high-functioning autistic men and 8 handedness and age-matched controls were included. Visually prompted button presses were performed with the preferred hand. For each subject, functional connectivity was computed in terms of BOLD signal correlation with the mean time series in bilateral visual area 17. Our hypothesis of reduced dorsal stream connectivity in autism was only in part confirmed. Functional connectivity with superior parietal areas was not significantly reduced. However, the autism group showed significantly reduced connectivity with bilateral inferior frontal area 44, which is compatible with the hypothesis of mirror neuron defects in autism. More generally, our findings suggest that dorsal stream connectivity in autism may not be fully functional. PMID:15808991

Reduced functional connectivity between V1 and inferior frontal cortex associated with visuomotor performance in autism.

PubMed

Villalobos, Michele E; Mizuno, Akiko; Dahl, Branelle C; Kemmotsu, Nobuko; Müller, Ralph-Axel

2005-04-15

Some recent evidence has suggested abnormalities of the dorsal stream and possibly the mirror neuron system in autism, which may be responsible for impairments of joint attention, imitation, and secondarily for language delays. The current study investigates functional connectivity along the dorsal stream in autism, examining interregional blood oxygenation level dependent (BOLD) signal cross-correlation during visuomotor coordination. Eight high-functioning autistic men and eight handedness and age-matched controls were included. Visually prompted button presses were performed with the preferred hand. For each subject, functional connectivity was computed in terms of BOLD signal correlation with the mean time series in bilateral visual area 17. Our hypothesis of reduced dorsal stream connectivity in autism was only in part confirmed. Functional connectivity with superior parietal areas was not significantly reduced. However, the autism group showed significantly reduced connectivity with bilateral inferior frontal area 44, which is compatible with the hypothesis of mirror neuron defects in autism. More generally, our findings suggest that dorsal stream connectivity in autism may not be fully functional.

Combined laser treatment in a patient with pigment dispersion secondary to a large iris pigment epithelial cyst.

PubMed

Aykan, Umit; Yıldırım, Ozlem

2012-09-01

We reported a case of bilateral extensive iris pigment epithelial cysts masquerading as pigment dispersion. A-30-year-old male patient presented with a dull pain in both eyes and a decreased visual acuity OD. He underwent a complete ophthalmic examination. OD was injected and the cells were graded as +3 and pigmented a +2, in the OS. Intraocular pressures (IOP) were measured as 42 (OD) and 22 (OS) mmHg. Gonioscopy revealed a confluent accumulation of dense pigment in both eyes. Visual fields, peripapillary retinal nerve fiber layer thickness (Spectral OCT/SLO OTI-OPKO Health. Inc, Miami, FL) and optic nerve head tomography (HRT-II Heidelberg Engineering, Heidelberg, Germany) results were within normal limits. On ultrasound biomicroscopy (UBM), bilateral extensive cysts were identified in the midzonal portion of the iris and in the ciliary body. An, antiglaucomatous treatment was started. Then, we decided to perform both Nd:YAG laser iridocystotomyc and selective laser trabeculoplasty. Fourteen months after the combined therapy, the cysts had not recurred, and still apposed and the IOPs were under control without medication.

Towards disparity joint upsampling for robust stereoscopic endoscopic scene reconstruction in robotic prostatectomy

NASA Astrophysics Data System (ADS)

Luo, Xiongbiao; McLeod, A. Jonathan; Jayarathne, Uditha L.; Pautler, Stephen E.; Schlacta, Christopher M.; Peters, Terry M.

2016-03-01

Three-dimensional (3-D) scene reconstruction from stereoscopic binocular laparoscopic videos is an effective way to expand the limited surgical field and augment the structure visualization of the organ being operated in minimally invasive surgery. However, currently available reconstruction approaches are limited by image noise, occlusions, textureless and blurred structures. In particular, an endoscope inside the body only has the limited light source resulting in illumination non-uniformities in the visualized field. These limitations unavoidably deteriorate the stereo image quality and hence lead to low-resolution and inaccurate disparity maps, resulting in blurred edge structures in 3-D scene reconstruction. This paper proposes an improved stereo correspondence framework that integrates cost-volume filtering with joint upsampling for robust disparity estimation. Joint bilateral upsampling, joint geodesic upsampling, and tree filtering upsampling were compared to enhance the disparity accuracy. The experimental results demonstrate that joint upsampling provides an effective way to boost the disparity estimation and hence to improve the surgical endoscopic scene 3-D reconstruction. Moreover, the bilateral upsampling generally outperforms the other two upsampling methods in disparity estimation.

Bilateral fungal keratitis with ring infiltrates: a rare scenario.

PubMed

Chaniyara, Manthan Hasmukhbhai; Pujari, Amar; Urkude, Jayanand; Sharma, Namrata

2017-10-09

A 12-year-old boy presented to the emergency department with chief complaints of pain, redness, discharge and diminution of vision in both eyes over the previous 20 days. There was no history of preceding trauma, contact lens use, any eye drop usage or ocular surgery. Systemic history was not significant. Presenting uncorrected visual acuity in his right eye was counting fingers at 1 m and 20/200 in the left eye, with accurate projection of rays in both eyes. Slit lamp biomicroscopy showed the presence of bilateral diffuse conjunctival congestion, corneal ring infiltrates and epithelial defect with corneal oedema. Potassium hydroxide wet mount showed the presence of septate fungal hyphae. The patient was treated with topical 5% natamycin and 1% voriconazole over a period of 6 weeks. Best-corrected visual acuity was 20/600 in the right eye and 20/20 in the left eye at 6-month follow-up. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Bilateral versus unilateral interlaminar approach for bilateral decompression in patients with single-level degenerative lumbar spinal stenosis: a multicenter retrospective study of 175 patients on postoperative pain, functional disability, and patient satisfaction.

PubMed

den Boogert, Hugo F; Keers, Joost C; Marinus Oterdoom, D L; Kuijlen, Jos M A

2015-09-01

The bilateral and unilateral interlaminar techniques for bilateral decompression both demonstrate good results for the treatment of degenerative lumbar spinal stenosis (DLSS). Although there is some discussion about which approach is more effective, studies that directly compare these two popular techniques are rare. To address this shortcoming, this study compares postoperative functional disability, pain, and patient satisfaction among patients with single-level DLSS who underwent bilateral decompression using either a bilateral or unilateral approach. This retrospective study included patients who underwent operations between November 1, 2009, and October 1, 2011. These patients underwent single-level bilateral decompressive surgery using either the bilateral or unilateral interlaminar approach at one of 5 participating hospitals. Exclusion criteria included previous lumbar surgery, additional disc surgery, and spondylolisthesis requiring fusion surgery. Primary outcome measures included bodily pain (as reported using the visual analog scale [VAS]), the Roland-Morris Disability Questionnaire (RMDQ), and the Oswestry Disability Index (ODI). In addition, reductions in leg and back symptoms and the patient's general evaluation of the procedure were queried. Finally, patient satisfaction and surgical parameters were evaluated. Questionnaires were sent to each patient's home, and electronic patient files were used to collect the data. One hundred and seventy-five patients returned the questionnaire (74.4% response rate; 68 and 107 patients who underwent the bilateral or unilateral approach, respectively). Mean age at surgery was 68 years (range 34-89 years), and the mean follow-up period was 14.2 months (range 3.3-27.4 years). There were no significant differences in ODI (20.3 vs 22.6 for the bilateral and unilateral approaches, respectively), RMDQ (3.99 vs 4.8, respectively), or pain scores between treatment groups. Back symptoms were reduced in 74.8% (bilateral: 74.6% vs unilateral: 75%; not significant), and leg symptoms in 80.6% of the patients (bilateral: 73.1% vs unilateral: 85.4%; p = 0.048). In total, 72.1% (bilateral) and 80.0% (unilateral) of patients reported good overall treatment results (p = 0.226). Significantly more patients in the unilateral group reported a better overall satisfaction with the procedure (82.1% vs 69.1%; p = 0.047). There were no differences in postoperative functional disability and pain between the surgical techniques. The significant differences in patient satisfaction and reduction in leg symptoms were unrelated to surgical technique. The overall treatment results were satisfactory. Both techniques are safe and effective options for treating patients with single-level DLSS.

Bilateral totally extraperitoneal (TEP) repair of the ultrasound-diagnosed asymptomatic contralateral inguinal hernia.

PubMed

Malouf, Phillip A; Descallar, Joseph; Berney, Christophe R

2018-02-01

The aim of this series is to determine the clinical utility of routine ultrasound (US) of the contralateral, clinically normal groin when a unilateral inguinal hernia is referred for hernia repair-specifically assessing the morbidity and short-term change in quality-of-life (QoL) due to repair of this occult contralateral hernia when also repairing the symptomatic side. TEP inguinal hernia repair affords the opportunity to repair any groin hernia through the same small incisions. US detects 96.6% of groin hernias with 84.4% specificity. 234 consecutive male patients with clinically unilateral and clinically bilateral hernia were enrolled; those with a clinically unilateral hernia were sent for groin US and if positive, a bilateral TEP groin hernia repair was performed (USBH). If negative, a unilateral TEP groin hernia repair was performed (UNIH). Carolina's comfort scales (CCS) and visual analogue scores (VAS) were recorded at 2 and 6 weeks postoperatively, while a modified CCS (MCCS) was recorded for all patients preoperatively. Bilateral TEP repair resulted in higher VAS scores than unilateral repair at 2 weeks but not 6 weeks. CCS were worse in the USBH group than UNIH group at 2 weeks but were similar by 6 weeks. Complications' rates were similar amongst all 3 groups. Factors contributing to worse scores were: smaller hernia, complications, worse preoperative MCCS results, recurrent hernia and bilateral rather than unilateral repair. Bilateral TEP for the clinically unilateral groin hernia with an occult contralateral groin hernia can be performed without increased morbidity, accepting a minor and very temporary impairment of QoL.

The effects of virtual reality-based bilateral arm training on hemiplegic children's upper limb motor skills.

PubMed

Do, Ji-Hye; Yoo, Eun-Young; Jung, Min-Ye; Park, Hae Yean

2016-01-01

Hemiplegic cerebral palsy is a neurological symptom appearing on the unilateral arm and leg of the body that causes affected upper/lower limb muscle weakening and dysesthesia and accompanies tetany and difficulties in postural control due to abnormal muscle tone, and difficulties in body coordination. The purpose of this study was to examine the impact of virtual reality-based bilateral arm training on the motor skills of children with hemiplegic cerebral palsy, in terms of their upper limb motor skills on the affected side, as well as their bilateral coordination ability. The research subjects were three children who were diagnosed with hemiplegic cerebral palsy. The research followed an ABA design, which was a single-subject experimental design. The procedure consisted of a total of 20 sessions, including four during the baseline period (A1), 12 during the intervention period (B), and four during the baseline regression period (A2), For the independent variable bilateral arm training based on virtual reality, Nintendo Wii game was played for 30 minutes in each of the 12 sessions. For the dependent variables of upper limb motor skills on the affected side and bilateral coordination ability, a Wolf Motor Function Test (WMFT) was carried out for each session and the Pediatric Motor Activity Log (PMAL) was measured before and after the intervention, as well as after the baseline regression period. To test bilateral coordination ability, shooting baskets in basketball with both hands and moving large light boxes were carried out under operational definitions, with the number of shots and time needed to move boxes measured. The results were presented using visual graphs and bar graphs. The study's results indicated that after virtual reality-based bilateral arm training, improvement occurred in upper limb motor skills on the affected sides, and in bilateral coordination ability, for all of the research subjects. Measurements of the effects of sustained therapy after completion of the intervention, during the baseline regression period, revealed that upper limb motor skills on the affected side and bilateral coordination ability were better than in the baseline period for all subjects. This study confirmed that for children with hemiplegic with cerebral palsy, bilateral arm training based on virtual reality can be an effective intervention method for enhancing the upper limb motor skills on the affected side, as well as bilateral coordination ability.

Dysflective cones: Visual function and cone reflectivity in long-term follow-up of acute bilateral foveolitis.

PubMed

Tu, Joanna H; Foote, Katharina G; Lujan, Brandon J; Ratnam, Kavitha; Qin, Jia; Gorin, Michael B; Cunningham, Emmett T; Tuten, William S; Duncan, Jacque L; Roorda, Austin

2017-09-01

Confocal adaptive optics scanning laser ophthalmoscope (AOSLO) images provide a sensitive measure of cone structure. However, the relationship between structural findings of diminished cone reflectivity and visual function is unclear. We used fundus-referenced testing to evaluate visual function in regions of apparent cone loss identified using confocal AOSLO images. A patient diagnosed with acute bilateral foveolitis had spectral-domain optical coherence tomography (SD-OCT) (Spectralis HRA + OCT system [Heidelberg Engineering, Vista, CA, USA]) images indicating focal loss of the inner segment-outer segment junction band with an intact, but hyper-reflective, external limiting membrane. Five years after symptom onset, visual acuity had improved from 20/80 to 20/25, but the retinal appearance remained unchanged compared to 3 months after symptoms began. We performed structural assessments using SD-OCT, directional OCT (non-standard use of a prototype on loan from Carl Zeiss Meditec) and AOSLO (custom-built system). We also administered fundus-referenced functional tests in the region of apparent cone loss, including analysis of preferred retinal locus (PRL), AOSLO acuity, and microperimetry with tracking SLO (TSLO) (prototype system). To determine AOSLO-corrected visual acuity, the scanning laser was modulated with a tumbling E consistent with 20/30 visual acuity. Visual sensitivity was assessed in and around the lesion using TSLO microperimetry. Complete eye examination, including standard measures of best-corrected visual acuity, visual field tests, color fundus photos, and fundus auto-fluorescence were also performed. Despite a lack of visible cone profiles in the foveal lesion, fundus-referenced vision testing demonstrated visual function within the lesion consistent with cone function. The PRL was within the lesion of apparent cone loss at the fovea. AOSLO visual acuity tests were abnormal, but measurable: for trials in which the stimulus remained completely within the lesion, the subject got 48% correct, compared to 78% correct when the stimulus was outside the lesion. TSLO microperimetry revealed reduced, but detectible, sensitivity thresholds within the lesion. Fundus-referenced visual testing proved useful to identify functional cones despite apparent photoreceptor loss identified using AOSLO and SD-OCT. While AOSLO and SD-OCT appear to be sensitive for the detection of abnormal or absent photoreceptors, changes in photoreceptors that are identified with these imaging tools do not correlate completely with visual function in every patient. Fundus-referenced vision testing is a useful tool to indicate the presence of cones that may be amenable to recovery or response to experimental therapies despite not being visible on confocal AOSLO or SD-OCT images.

First and second eye cataract surgery and driver self-regulation among older drivers with bilateral cataract: a prospective cohort study.

PubMed

Agramunt, Seraina; Meuleners, Lynn B; Fraser, Michelle L; Chow, Kyle C; Ng, Jonathon Q; Raja, Vignesh

2018-02-17

Driving a car is the most common form of transport among the older population. Common medical conditions such as cataract, increase with age and impact on the ability to drive. To compensate for visual decline, some cataract patients may self-regulate their driving while waiting for cataract surgery. However, little is known about the self-regulation practices of older drivers throughout the cataract surgery process. The aim of this study is to assess the impact of first and second eye cataract surgery on driver self-regulation practices, and to determine which objective measures of vision are associated with driver self-regulation. Fifty-five older drivers with bilateral cataract aged 55+ years were assessed using the self-reported Driving Habits Questionnaire, the Mini-Mental State Examination and three objective visual measures in the month before cataract surgery, at least one to three months after first eye cataract surgery and at least one month after second eye cataract surgery. Participants' natural driving behaviour in four driving situations was also examined for one week using an in-vehicle monitoring device. Two separate Generalised Estimating Equation logistic models were undertaken to assess the impact of first and second eye cataract surgery on driver-self-regulation status and which changes in visual measures were associated with driver self-regulation status. The odds of being a self-regulator in at least one driving situation significantly decreased by 70% after first eye cataract surgery (OR: 0.3, 95% CI: 0.1-0.7) and by 90% after second eye surgery (OR: 0.1, 95% CI: 0.1-0.4), compared to before first eye surgery. Improvement in contrast sensitivity after cataract surgery was significantly associated with decreased odds of self-regulation (OR: 0.02, 95% CI: 0.01-0.4). The findings provide a strong rationale for providing timely first and second eye cataract surgery for older drivers with bilateral cataract, in order to improve their mobility and independence.

Ageing diminishes the modulation of human brain responses to visual food cues by meal ingestion.

PubMed

Cheah, Y S; Lee, S; Ashoor, G; Nathan, Y; Reed, L J; Zelaya, F O; Brammer, M J; Amiel, S A

2014-09-01

Rates of obesity are greatest in middle age. Obesity is associated with altered activity of brain networks sensing food-related stimuli and internal signals of energy balance, which modulate eating behaviour. The impact of healthy mid-life ageing on these processes has not been characterised. We therefore aimed to investigate changes in brain responses to food cues, and the modulatory effect of meal ingestion on such evoked neural activity, from young adulthood to middle age. Twenty-four healthy, right-handed subjects, aged 19.5-52.6 years, were studied on separate days after an overnight fast, randomly receiving 50 ml water or 554 kcal mixed meal before functional brain magnetic resonance imaging while viewing visual food cues. Across the group, meal ingestion reduced food cue-evoked activity of amygdala, putamen, insula and thalamus, and increased activity in precuneus and bilateral parietal cortex. Corrected for body mass index, ageing was associated with decreasing food cue-evoked activation of right dorsolateral prefrontal cortex (DLPFC) and precuneus, and increasing activation of left ventrolateral prefrontal cortex (VLPFC), bilateral temporal lobe and posterior cingulate in the fasted state. Ageing was also positively associated with the difference in food cue-evoked activation between fed and fasted states in the right DLPFC, bilateral amygdala and striatum, and negatively associated with that of the left orbitofrontal cortex and VLPFC, superior frontal gyrus, left middle and temporal gyri, posterior cingulate and precuneus. There was an overall tendency towards decreasing modulatory effects of prior meal ingestion on food cue-evoked regional brain activity with increasing age. Healthy ageing to middle age is associated with diminishing sensitivity to meal ingestion of visual food cue-evoked activity in brain regions that represent the salience of food and direct food-associated behaviour. Reduced satiety sensing may have a role in the greater risk of obesity in middle age.

Rethinking Airbag Safety: Airbag Injury Causing Bilateral Blindness

PubMed Central

Ogun, Olufunmilola Abimbola; Ikyaa, Sewuese Yangi; Ogun, Gabriel Olabiyi

2014-01-01

A healthy 40-year-old man, restrained in the front passenger seat, suffered visually disabling blunt ocular trauma following spontaneous release of the passenger side air-bag module, during vehicular deceleration, without an automobile crash. Though the driver-side airbag was also released, the driver was unharmed. The passenger suffered bilateral hyphema, bilateral vitreous hemorrhage and suspected posterior scleral rupture in the left eye and also had an eyebrow laceration, from impact with the dashboard panel covering the air-bag module, which was detached by the force of airbag deployment. This is the first reported case from West Africa and the first case in which part of the airbag module detached to cause additional trauma. This report adds to the growing burden of evidence world-wide, for a review of the safety aspects of the automobile airbag. This case clearly illustrates that although airbags reduce mortality, they carry a high risk of ocular morbidity, even with seat belt restraint. PMID:24791116

Monosynaptic rabies virus reveals premotor network organization and synaptic specificity of cholinergic partition cells.

PubMed

Stepien, Anna E; Tripodi, Marco; Arber, Silvia

2010-11-04

Movement is the behavioral output of neuronal activity in the spinal cord. Motor neurons are grouped into motor neuron pools, the functional units innervating individual muscles. Here we establish an anatomical rabies virus-based connectivity assay in early postnatal mice. We employ it to study the connectivity scheme of premotor neurons, the neuronal cohorts monosynaptically connected to motor neurons, unveiling three aspects of organization. First, motor neuron pools are connected to segmentally widely distributed yet stereotypic interneuron populations, differing for pools innervating functionally distinct muscles. Second, depending on subpopulation identity, interneurons take on local or segmentally distributed positions. Third, cholinergic partition cells involved in the regulation of motor neuron excitability segregate into ipsilaterally and bilaterally projecting populations, the latter exhibiting preferential connections to functionally equivalent motor neuron pools bilaterally. Our study visualizes the widespread yet precise nature of the connectivity matrix for premotor interneurons and reveals exquisite synaptic specificity for bilaterally projecting cholinergic partition cells. Copyright © 2010 Elsevier Inc. All rights reserved.

Granulomatous uveitis and reactive arthritis as manifestations of post-streptococcal syndrome.

PubMed

Abderrahim, Kais; Chebil, Ahmed; Falfoul, Yosra; Bouladi, Mejda; El Matri, Leila

2015-10-01

To report a case of bilateral granulomatous post-streptococcal syndrome uveitis in association with reactive arthritis as manifestation of post-streptococcal syndrome. To our knowledge, this could represent the first reported case in the literature. A 9-year-old girl, with no past ocular history, presented with a 5-day history of bilateral blurred vision, red eyes, photophobia and walking difficulties because of a right ankle pain. Ophthalmic examination disclosed a visual acuity limited to hand motion, mutton-fat keratic precipitates, anterior chamber cells and posterior synechiae in both eyes. Ocular pressure was normal. Physical examination showed a fever (38 °C), inflammatory ankle arthritis and scarlet fever (streptococcal lesion). Anti-streptococcal lysine O titer was 419 μ/ml. The patient was treated with topical steroids, cycloplegics, high-dose oral steroids and preventive course of penicillin with total improvement and no recurrence. Post-streptococcal syndrome should be considered in the etiology of acute bilateral granulomatous uveitis in children, and anti-streptococcal lysine O titer should be considered in serodiagnostic testing.

Management of Chronic Hypotony following Bilateral Uveitis in a Patient Treated with Pembrolizumab for Cutaneous Metastatic Melanoma.

PubMed

Reid, Gerard; Lorigan, Paul; Heimann, Heinrich; Hovan, Marta

2018-04-19

To describe the presentation and management of severe ocular adverse events following treatment with pembrolizumab for cutaneous metastatic melanoma. Interventional case report. A 73-year-old Caucasian man receiving pembrolizumab treatment for metastatic melanoma presented with panuveitis and subsequent profound hypotony, choroidal effusions, and optic disk swelling bilaterally. Oral prednisolone controlled intraocular inflammation. However, bilateral hypotony persisted which was managed over a 12-month period with ocular viscoelastic device injections into the anterior chamber of both eyes. There was also phacoemulsification with pars plana vitrectomy (PPV) and silicone oil (SO) tamponade performed on the left eye only. Intraocular pressure (IOP) stabilized (>6 mmHg) with best-corrected visual acuity of 6/60. We report a severe adverse event from pembrolizumab therapy resulting in uveitis and persistent hypotony. Repeat injections of high viscosity OVD achieved an increase in IOP up to 12 months. This technique may be a useful adjuvant or alternative to PPV and SO.

Spontaneous Resolution of Intravitreal Steroid-Induced Bilateral Cytomegalovirus Retinitis

PubMed Central

Cho, Won Bin; Kim, Hyung Chan

2012-01-01

A 73-year-old woman underwent vitrectomy and intravitreal triamcinolone acetonide (IVTA) of the right eye and cataract surgery with IVTA of the left eye, for bilateral diabetic macular edema. The patient presented with visual loss in both eyes three-months postoperatively. The fundoscopic examination revealed white-yellow, necrotic peripheral lesions in the superotemporal quadrant of both eyes. Although bilateral acute retinal necrosis was suspected, azotemia resulting from diabetic nephropathy limited the use of acyclovir. Antiviral treatment was not started. A sample of the aqueous humor for polymerase chain reaction (PCR) analysis was obtained. One week later, the PCR results indicated the presence of cytomegalovirus (CMV). Since the retinal lesions did not progress and did not threaten the macula, the patient was followed without treatment for CMV. The retinal lesions progressively regressed and completely resolved in both eyes by six months of follow-up. Patients with IVTA-induced CMV retinitis may not require systemic treatment with ganciclovir. PMID:22511845

Stem Cell Ophthalmology Treatment Study (SCOTS) for retinal and optic nerve diseases: a case report of improvement in relapsing auto-immune optic neuropathy.

PubMed

Weiss, Jeffrey N; Levy, Steven; Benes, Susan C

2015-09-01

We present the results from a patient with relapsing optic neuropathy treated within the Stem Cell Ophthalmology Treatment Study (SCOTS). SCOTS is an Institutional Review Board approved clinical trial and has become the largest ophthalmology stem cell study registered at the National Institutes of Health to date (www.clinicaltrials.gov Identifier NCT 01920867). SCOTS utilizes autologous bone marrow-derived stem cells (BMSCs) for treatment of retinal and optic nerve diseases. Pre-treatment and post-treatment comprehensive eye exams of a 54 year old female patient were performed both at the Florida Study Center, USA and at The Eye Center of Columbus, USA. As a consequence of a relapsing optic neuritis, the patient's previously normal visual acuity decreased to between 20/350 and 20/400 in the right eye and to 20/70 in the left eye. Significant visual field loss developed bilaterally. The patient underwent a right eye vitrectomy with injection of BMSCs into the optic nerve of the right eyeand retrobulbar, subtenon and intravitreal injection of BMSCs in the left eye. At 15 months after SCOTS treatment, the patient's visual acuity had improved to 20/150 in the right eye and 20/20 in the left eye. Bilateral visual fields improved markedly. Both macular thickness and fast retinal nerve fiber layer thickness were maximally improved at 3 and 6 months after SCOTS treatment. The patient also reduced her mycophenylate dose from 1,500 mg per day to 500 mg per day and required no steroid pulse therapy during the 15-month follow up.

The differential effects of acute right- vs. left-sided vestibular failure on brain metabolism.

PubMed

Becker-Bense, Sandra; Dieterich, Marianne; Buchholz, Hans-Georg; Bartenstein, Peter; Schreckenberger, Mathias; Brandt, Thomas

2014-07-01

The human vestibular system is represented in the brain bilaterally, but it has functional asymmetries, i.e., a dominance of ipsilateral pathways and of the right hemisphere in right-handers. To determine if acute right- or left-sided unilateral vestibular neuritis (VN) is associated with differential patterns of brain metabolism in areas representing the vestibular network and the visual-vestibular interaction, patients with acute VN (right n = 9; left n = 13) underwent resting state (18)F-FDG PET once in the acute phase and once 3 months later after central vestibular compensation. The contrast acute vs. chronic phase showed signal differences in contralateral vestibular areas and the inverse contrast in visual cortex areas, both more pronounced in VN right. In VN left additional regions were found in the cerebellar hemispheres and vermis bilaterally, accentuated in severe cases. In general, signal changes appeared more pronounced in patients with more severe vestibular deficits. Acute phase PET data of patients compared to that of age-matched healthy controls disclosed similarities to these patterns, thus permitting the interpretation that the signal changes in vestibular temporo-parietal areas reflect signal increases, and in visual areas, signal decreases. These data imply that brain activity in the acute phase of right- and left-sided VN exhibits different compensatory patterns, i.e., the dominant ascending input is shifted from the ipsilateral to the contralateral pathways, presumably due to the missing ipsilateral vestibular input. The visual-vestibular interaction patterns were preserved, but were of different prominence in each hemisphere and more pronounced in patients with right-sided failure and more severe vestibular deficits.

Advanced pigment dispersion glaucoma secondary to phakic intraocular collamer lens implant.

PubMed

Ye, Clara; Patel, Cajal K; Momont, Anna C; Liu, Yao

2018-06-01

We report a case of pigment dispersion glaucoma secondary to uncomplicated phakic intraocular collamer lens (ICL) (Visian ICL™, Staar Inc., Monrovia, CA) implant that resulted in advanced visual field loss. A 50-year-old man presented for routine follow-up status post bilateral phakic intraocular collamer lens (ICL) placement 8 years earlier. He was incidentally found to have a decline in visual acuity from an anterior subcapsular cataract and elevated intraocular pressure (IOP) in the left eye. There were signs of pigment dispersion and no evidence of angle closure. Diffuse optic nerve thinning was consistent with advanced glaucomatous visual field defects. Pigment dispersion was also present in the patient's right eye, but without elevated IOP or visual field defects. The patient was treated with topical glaucoma medications and the phakic ICL in the left eye was removed concurrently with cataract surgery to prevent further visual field loss. Pigment dispersion glaucoma is a serious adverse outcome after phakic ICL implantation and regular post-operative monitoring may prevent advanced visual field loss.

[Juvenile myasthenia gravis in sub-Saharan Africa: a case study of two consanguine sisters born from consanguinity in Togo].

PubMed

Maneh, Nidain; Apetse, Kossivi; Diatewa, Bénédicte Marèbe; Domingo, Sidik Abou-Bakr; Agba, Aidé Isabelle; Ayena, Koffi Didier; Balogou, Koffi Agnon; Balo, Komi Patrice

2017-01-01

Myasthenia gravis is a rare acquired autoimmune pathology causing neuromuscular transmission impairment. Juvenile onset of myasthenia gravis is often characterized by ocular involvement. We report two cases of ocular juvenile myasthenia gravis (JMG) in two siblings. They were two young girls, XA and XB, aged 11 and 9 years, of Malian origin, residing in Togo, born from first-degree of consanguinity presenting to Ophthalmology due to progressive decrease in visual acuity. XA showed visual acuity 8/10 on both eyes while XB showed improvement in visual acuity from 3/10 to 7/10 using a pinhole occluder, suggesting ametropia. XA had a 2-year history of bilateral ptosis lifting the upper eyelid of 7 mm, while XB had a 3-year history of bilateral ptosis with no lifting of the upper eyelid. Ice pack test was strongly positive in both patients. They had Cogan's lid twitch with paresis of the oculomotor nerve without diplopia. The dosage of acetylcholine receptor autoantibodies was normal. The diagnosis of JMG associated with ametropia was suspected. Ametropia was corrected by glasses and a specific treatment with pyridostigmine was initiated, but both patients were lost to follow-up. Autoimmune myasthenia gravis with inaugural ophthalmologic manifestation is rare but it can occur among children living in sub-Saharan Africa. Studies should be conducted to establish the features of this disease.

Foldable iris-fixated intraocular lens implantation in children.

PubMed

Ryan, Andrea; Hartnett, Claire; Lanigan, Bernadette; O'Keefe, Michael

2012-09-01

  To describe the results of foldable iris-fixated intraocular lens (IOL) implantation in children.   Children with high bilateral or unilateral myopia who were intolerant of spectacle or contact lens correction were implanted with an iris-fixated foldable IOL and prospectively followed. We measured pre- and postoperative visual acuity, refraction, endothelial cell density (ECD) and National Eye Institute Visual Functioning Questionnaire-25.   Eleven eyes of six children were implanted. Indications were high bilateral myopia in children with comorbid neurobehavioural disorders, high anisometropia and high myopic astigmatism. Mean preoperative spherical equivalent (SE) refraction was -14.6 dioptres (D)±4.2 SD. Mean follow-up was 15 months. Postoperative SE refraction was -2.40 D±2.40 SD. Corrected distance visual acuity (CDVA) improved from mean logMAR 0.84±0.4 SD to postoperative 0.67±0.34 SD (p=0.005). CDVA was reduced because of coexistent ocular disorders and amblyopia. Vision-related quality of life (QOL) measures improved significantly. There were no intraoperative or postoperative serious complications.   Foldable iris-fixated IOL insertion can give a significant improvement in vision and in vision-related QOL in a subset of paediatric patients with special refractive needs who are intolerant to conventional treatment. Long-term follow-up is required for monitoring of ECD. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

Bilateral visual loss and cerebral infarction after spleen embolization in a trauma patient with idiopathic thrombocytopenic purpura: A case report.

PubMed

Wang, Wei-Ting; Li, Yu-Yu; Lin, Wan-Ching; Chen, Jen-Yin; Lan, Kuo-Mao; Sun, Cheuk-Kwan; Hung, Kuo-Chuan

2018-04-01

Splenic artery embolization (SAE) is a common procedure in trauma patients with blunt splenic injuries. We report a case of acute ischemic stroke following orthopedic surgery in a patient with post-SAE reactive thrombocytosis. A 37-year-old woman with idiopathic thrombocytopenic purpura (ITP) suffered from multiple trauma scheduled for open reduction and internal fixation for right tibial and left radius fracture five days after SAE. The patient did not have any thromboembolic complications, although the platelet counts increased from 43 × 10/L to 568 × 10/L within two days after SAE. Surgery was completed under general anesthesia with tracheal intubation without complications. The patient complained of visual loss followed by limb weakness on the fourth and eighth hour postoperatively. Magnetic resonance imaging (MRI) of head demonstrated ischemic change over bilateral basal ganglia, and occipital areas, suggesting the diagnosis of cortical blindness. To suppress platelet count and avoid platelet hyper-aggregation, anti-platelet drug (i.e., oral aspirin 100 mg daily), hydration, and hydroxyurea (i.e., 20 mg/kg daily) were used for the treatment of reactive thrombocytosis. Although right-sided hemiparesis persisted, the patient reported mild visual recovery. She was discharged four months after SAE with active rehabilitation. Our report highlights an increased risk of acute arterial thromboembolic events in patients with reactive thrombocytosis, especially those undergoing surgery.

Altered cortical activation and connectivity patterns for visual attention processing in young adults post-traumatic brain injury: A functional near infrared spectroscopy study.

PubMed

Wu, Ziyan; Mazzola, Catherine A; Catania, Lori; Owoeye, Oyindamola; Yaramothu, Chang; Alvarez, Tara; Gao, Yu; Li, Xiaobo

2018-06-01

This study aimed at understanding the neurobiological mechanisms associated with inattention induced by traumatic brain injury (TBI). To eliminate the potential confounding caused by the heterogeneity of TBI, we focused on young adults postsports-related concussion (SRC). Functional near-infrared spectroscopy (fNIRS) data were collected from 27 young adults post-SRC and 27 group-matched normal controls (NCs), while performing a visual sustained attention task. Task responsive cortical activation maps and pairwise functional connectivity among six regions of interest were constructed for each subject. Correlations among the brain imaging measures and clinical measures of attention were calculated in each group. Compared to the NCs, the SRC group showed significantly increased brain activation in left middle frontal gyrus (MFG) and increased functional connectivity between right inferior occipital cortex (IOC) bilateral calcarine gyri (CG). The left MFG activation magnitude was significantly negatively correlated with the hyperactive/impulsive symptom severity measure in the NCs, but not in the patients. The right hemisphere CG-IOC functional connectivity showed a significant positive correlation with the hyperactive/impulsive symptom severity measure in patients, but not in NCs. The current data suggest that abnormal left MFG activation and hyper-communications between right IOC and bilateral CG during visual attention processing may significantly contribute to behavioral manifestations of attention deficits in patients with TBI. © 2018 John Wiley & Sons Ltd.

Haptically facilitated bimanual training combined with augmented visual feedback in moderate to severe hemiplegia.

PubMed

Boos, Amy; Qiu, Qinyin; Fluet, Gerard G; Adamovich, Sergei V

2011-01-01

This study describes the design and feasibility testing of a hand rehabilitation system that provides haptic assistance for hand opening in moderate to severe hemiplegia while subjects attempt to perform bilateral hand movements. A cable-actuated exoskeleton robot assists the subjects in performing impaired finger movements but is controlled by movement of the unimpaired hand. In an attempt to combine the neurophysiological stimuli of bilateral movement and action observation during training, visual feedback of the impaired hand is replaced by feedback of the unimpaired hand, either by using a sagittaly oriented mirror or a virtual reality setup with a pair of virtual hands presented on a flat screen controlled with movement of the unimpaired hand, providing a visual image of their paretic hand moving normally. Joint angles for both hands are measured using data gloves. The system is programmed to maintain a symmetrical relationship between the two hands as they respond to commands to open and close simultaneously. Three persons with moderate to severe hemiplegia secondary to stroke trained with the system for eight, 30 to 60 minute sessions without adverse events. Each demonstrated positive motor adaptations to training. The system was well tolerated by persons with moderate to severe upper extremity hemiplegia. Further testing of its effects on motor ability with a broader range of clinical presentations is indicated.

Inversion effect in the visual processing of Chinese character: an fMRI study.

PubMed

Zhao, Jizheng; Liu, Jiangang; Li, Jun; Liang, Jimin; Feng, Lu; Ai, Lin; Tian, Jie

2010-07-05

Chinese people engage long-term processing of characters. It has been demonstrated that the presented orientation affects the perception of several types of stimuli when people have possessed expertise with them, e.g. face, body, and scene. However, the influence of inversion on the neural mechanism of Chinese character processing has not been sufficiently discussed. In the present study, a functional magnetic resonance imaging (fMRI) experiment is performed to examine the effect of inversion on Chinese character processing, which employs Chinese character, face and house as stimuli. The region of interest analysis demonstrates inversion leads to neural response increases for Chinese character in left fusiform character-preferential area, bilateral fusiform object-preferential area and bilateral occipital object-preferential area, and such inversion-caused changes in the response pattern of characters processing are highly similar to those of faces processing but quiet different from those of houses processing. Whole brain analysis reveals the upright characters recruit several language regions for phonology and semantic processing, however, the inverted characters activated extensive regions related to the visual information processing. Our findings reveal a shift from the character-preferential processing route to the generic object processing steam within visual cortex when the characters are inverted, and suggest that different mechanisms may underlie the upright and the inverted Chinese character, respectively. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Neurochemical changes in the pericalcarine cortex in congenital blindness attributable to bilateral anophthalmia

PubMed Central

Coullon, Gaelle S. L.; Emir, Uzay E.; Fine, Ione; Watkins, Kate E.

2015-01-01

Congenital blindness leads to large-scale functional and structural reorganization in the occipital cortex, but relatively little is known about the neurochemical changes underlying this cross-modal plasticity. To investigate the effect of complete and early visual deafferentation on the concentration of metabolites in the pericalcarine cortex, 1H magnetic resonance spectroscopy was performed in 14 sighted subjects and 5 subjects with bilateral anophthalmia, a condition in which both eyes fail to develop. In the pericalcarine cortex, where primary visual cortex is normally located, the proportion of gray matter was significantly greater, and levels of choline, glutamate, glutamine, myo-inositol, and total creatine were elevated in anophthalmic relative to sighted subjects. Anophthalmia had no effect on the structure or neurochemistry of a sensorimotor cortex control region. More gray matter, combined with high levels of choline and myo-inositol, resembles the profile of the cortex at birth and suggests that the lack of visual input from the eyes might have delayed or arrested the maturation of this cortical region. High levels of choline and glutamate/glutamine are consistent with enhanced excitatory circuits in the anophthalmic occipital cortex, which could reflect a shift toward enhanced plasticity or sensitivity that could in turn mediate or unmask cross-modal responses. Finally, it is possible that the change in function of the occipital cortex results in biochemical profiles that resemble those of auditory, language, or somatosensory cortex. PMID:26180125

[Some special indications for wearing contact lenses (author's transl)].

PubMed

Müller, K

1978-12-01

The typical distinguishing features of special cases which require contact lenses for satisfactory vision are described. Hence in the first case with anisometria associated with irregular astigmatism of one eye, to which a toric soft contact lens was adapted. In the second case a visual acuity of only 0,6 monocular was attained with the best spectacle lens, however with contact lense the visual acuity was 1.25. Here a verdict from a social court is mentioned, which obliged the sickness insurance to take over the costs for such a case. In the third case the adaptation of contact lenses was undertaken after radical bilateral keratoplasty because of parenchymatous keratitis, and an improvement in visual acuity of at least 400% resulted.

LASIK flap buttonhole treated immediately by PRK with mitomycin C.

PubMed

Kymionis, George D; Portaliou, Dimitra M; Karavitaki, Alexandra E; Krasia, Maria S; Kontadakis, Georgios A; Stratos, Aimilianos; Yoo, Sonia H

2010-03-01

To describe the visual outcomes of three patients who had LASIK flap buttonhole and were treated immediately with photorefractive keratectomy (PRK) and topical mitomycin C (MMC) 0.02%. Three patients underwent bilateral LASIK with the SCHWIND Carriazo-Pendula 90 microm head microkeratome. In all three cases, a buttonhole flap occurred in the left eye. The flap was repositioned and phototherapeutic keratectomy for 50 microm was used for epithelial removal while immediate PRK with MMC was performed to treat the buttonhole flap. Three months after the procedure, uncorrected distance visual acuity and corrected distance visual acuity were 20/20 with regular topographic findings. Using PRK with MCC immediately after the occurrence of the LASIK flap buttonhole may be an effective treatment.

76 FR 12624 - Airworthiness Directives; Dassault-Aviation Model FALCON 7X Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-08

... modifying the applicable wiring and layout, a general visual inspection for absence of marks of the rear... States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of... likely to exist or develop on other products of the same type design. Differences Between This AD and the...

Femtosecond laser-assisted cataract surgery in anterior lenticonus due to Alport syndrome.

PubMed

Barnes, Alexander C; Roth, Allen S

2017-06-01

We describe a case of bilateral anterior lenticonus in a patient with Alport syndrome treated with femtosecond laser-assisted cataract surgery (FLACS). FLACS was performed without complication, and a desirable postoperative visual acuity was achieved. Femtosecond laser-assisted cataract surgery is an effective approach for managing patients with anterior lenticonus secondary to Alport syndrome.

The Preference for Symmetry in Flower-Naive and Not-so-Naive Bumblebees

ERIC Educational Resources Information Center

Plowright, C. M. S.; Evans, S. A.; Leung, J. Chew; Collin, C. A.

2011-01-01

Truly flower-naive bumblebees, with no prior rewarded experience for visits on any visual patterns outside the colony, were tested for their choice of bilaterally symmetric over asymmetric patterns in a radial-arm maze. No preference for symmetry was found. Prior training with rewarded black and white disks did, however, lead to a significant…

Fear Recognition Impairment in Early-Stage Alzheimer's Disease: When Focusing on the Eyes Region Improves Performance

ERIC Educational Resources Information Center

Hot, Pascal; Klein-Koerkamp, Yanica; Borg, Celine; Richard-Mornas, Aurelie; Zsoldos, Isabella; Adeline, Adeline Paignon; Anterion, Catherine Thomas; Baciu, Monica

2013-01-01

A decline in the ability to identify fearful expression has been frequently reported in patients with Alzheimer's disease (AD). In patients with severe destruction of the bilateral amygdala, similar difficulties have been reduced by using an explicit visual exploration strategy focusing on gaze. The current study assessed the possibility of…

VISUAL ACUITY IN PSEUDOXANTHOMA ELASTICUM.

PubMed

Risseeuw, Sara; Ossewaarde-van Norel, Jeannette; Klaver, Caroline C W; Colijn, Johanna M; Imhof, Saskia M; van Leeuwen, Redmer

2018-04-12

To assess the age-specific proportion of visual impairment in patients with pseudoxanthoma elasticum (PXE) and to compare this with foveal abnormality and similar data of late age-related macular degeneration patients. Cross-sectional data of 195 patients with PXE were reviewed, including best-corrected visual acuity and imaging. The World Health Organisation criteria were used to categorize bilateral visual impairment. These results were compared with similar data of 131 patients with late age-related macular degeneration from the Rotterdam study. Overall, 50 PXE patients (26.0%) were visually impaired, including 21 (11%) with legal blindness. Visual functioning declined with increasing age. In patients older than 50 years, 37% was visually impaired and 15% legally blind. Foveal choroidal neovascularization was found in 84% of eyes with a best-corrected visual acuity lower than 20/70 (0.30) and macular atrophy in the fovea in 16%. In late age-related macular degeneration patients, 40% were visually impaired and 13% legally blind. Visual impairment started approximately 20 years later as compared with PXE patients. Visual impairment and blindness are frequent in PXE, particularly in patients older than 50 years. Although choroidal neovascularization is associated with the majority of vision loss, macular atrophy is also common. The proportion of visual impairment in PXE is comparable with late age-related macular degeneration but manifests earlier in life.

Amblyopia.

PubMed

DeSantis, Diana

2014-06-01

Amblyopia refers to unilateral or bilateral reduction in best corrected visual acuity, not directly attributed to structural abnormality of the eye or posterior visual pathways. Early detection of amblyopia is crucial to obtaining the best response to treatment. Amblyopia responds best to treatment in the first few years of life. In the past several years a series of studies undertaken by the Pediatric Eye Disease Investigator Group (PEDIG) have been designed to evaluate traditional methods for treating amblyopia and provide evidence on which to base treatment decisions. This article summarizes and discusses the findings of the PEDIG studies to date. Copyright © 2014 Elsevier Inc. All rights reserved.

Unilateral pigmentary retinopathy--a review of literature and case presentation.

PubMed

Stamate, Alina-Cristina; Burcea, Marian; Zemba, Mihail

2016-01-01

To report a rare case of unilateral pigmentary retinopathy and describe the clinical and visual field characteristics of this particular case. We present the case of a 30-year-old male patient with a gradual loss of the visual field on his left eye (LE) for the past 10 years, with further gradual painless loss of his central visual field in the last year, and no similar symptoms in his right eye. His past medical and ocular history were unremarkable. No family history of acquired or inherited diseases was determined. Based on the history, clinical findings, and visual field examination, the diagnosis of unilateral pigmentary retinopathy was established. Visual acuity and visual field in the left eye (LE) were severely affected, while in the right eye (RE), they were completely normal. In this case, distinct features of pigmentary retinopathy were observed only in one eye, with the fellow eye being unaffected. The diagnosis requires a long follow-up period, visual field and electrophysiological testing to rule out a delayed onset of a bilateral form of pigmentary retinopathy.

Presumed topiramate retinopathy: a case report.

PubMed

Yeung, Tiffany L M; Li, Patrick S H; Li, Kenneth K W

2016-08-01

We report a case of peripheral pigmentary retinopathy and visual field loss following topiramate use for uncontrolled seizures. Such side effects have not been well documented despite the increasing use of topiramate in the past 10 years. A thorough search of available English literature revealed only a small number of reports of topiramate-induced retinopathy or visual field defects in humans. One similar case has been described. We are concerned about the possible rare instances of this occurrence in future patients and hence would like to propose a presumed correlation. A 48-year-old Chinese woman developed blurred vision after 9 months of topiramate use. Her visual acuity dropped from 1.2 to 0.7 in both eyes, with bilateral diffuse pigmentary retinopathy and a constricted visual field. Despite an improvement in visual acuity after cessation of the drug, the other clinical findings remained. The temporal relationship between the initiation of topiramate and the visual disturbance suggests that topiramate could be the cause of such signs and symptoms. Topiramate potentially causes pigmentary retinopathy and constricted visual field.

Bilateral Retrobulbar Optic Neuritis Caused by Varicella Zoster Virus in a Patient with AIDS

PubMed Central

Duda, Jose F.; Castro, Jose G.

2015-01-01

Aims To report on a case of bilateral retrobulbar optic neuritis in a patient with acquired immune deficiency syndrome (AIDS) caused by varicella-zoster virus (VZV); and to review the literature focusing on: cases reported, epidemiology, pathophysiology, diagnosis and treatment. Presentation of Case A 38-year-old woman with AIDS presented with a 10-day history of progressive bilateral visual loss and ocular pain. She had bilateral dilated pupils with no light perception; the fundoscopic examination was normal. Facial herpes zoster lesions appeared on the second day of hospitalization Magnetic resonance imaging (MRI) findings were compatible with a bilateral optic neuritis; the cerebrospinal fluid (CSF) showed pleocytosis, increased proteins and a positive VZV-DNA PCR. She was treated with intravenous acyclovir and corticosteroids and was able, when discharged 2 weeks after admission, to carry out activities of daily living. Discussion VZV retrobulbar optic neuritis has previously been reported in 12 patients with AIDS, more than half of the cases had concomitant herpes zoster and an associated retinopathy. A positive VZV-DNA in the CSF is indicative of VZV infection, initial use of intravenous acyclovir is recommended, and the concomitant use of corticosteroids would be a prudent choice; the duration of antiviral therapy remains undefined. Conclusion VZV retrobulbar optic neuritis in AIDS patients can occur with or without herpes zoster. It is a sight-threatening infectious and inflammatory process requiring the advice of specialists in infectious diseases, ophthalmology, neurology and viral microbiology. PMID:26740936

Meridional lenticular astigmatism associated with bilateral concurrent uveal metastases in renal cell carcinoma.

PubMed

Priluck, Joshua C; Grover, Sandeep; Chalam, Kv

2012-01-01

To demonstrate a case illustrating meridional lenticular astigmatism as a result of renal cell carcinoma uveal metastases. Case report with images. Clinical findings and diagnostic testing of a patient with acquired meridional lenticular astigmatism are described. The refraction revealed best-corrected visual acuity of 20/20-1 OD (-2.50 + 0.25 × 090) and 20/50 OS (-8.25 + 3.25 × 075). Bilateral concurrent renal cell carcinoma metastases to the choroid and ciliary body are demonstrated by utilizing ultrasonography, ultrawidefield fluorescein angiography, and unique spectral-domain optical coherence tomography. Metastatic disease should be included in the differential of acquired astigmatism. Spectral-domain optical coherence tomography, ultrawidefield fluorescein angiography, and ultrasonography have roles in delineating choroidal metastases.

Hemispheric Processing of Idioms and Irony in Adults With and Without Pervasive Developmental Disorder.

PubMed

Saban-Bezalel, Ronit; Mashal, Nira

2015-11-01

Previous studies on individuals with pervasive developmental disorders (PDD) have pointed to difficulties in comprehension of figurative language. Using the divided visual field paradigm, the present study examined hemispheric processing of idioms and irony in 23 adults with PDD and in 24 typically developing (TD) adults. The results show that adults with PDD were relatively unimpaired in understanding figurative language. While the TD group demonstrated a right hemisphere advantage in processing the non-salient meanings of idioms as well as the ironic endings of paragraphs, the PDD group processed these stimuli bilaterally. Our findings suggest that brain lateralization is atypical in adults with PDD. Successful performance along with bilateral brain activation suggests that the PDD group uses a compensation mechanism.

Atypical presentation of Best Disease.

PubMed

Gutiérrez-Montero, Ó; Reche-Sainz, J A; Peral Ortiz de la Torre, M J; Toledano-Fernández, N

2018-05-28

A 43-year-old man was treated for reduced visual acuity, initially attributed to strabismic amblyopia. On fundus examination, bilateral neurosensory detachments (NSD) were observed in posterior pole, surrounded by deposits of lipofuscin. His 3-year-old son was also examined and circumscribed NSD was observed with the presence of pseudohypopyon in OD and a fibrosis scar in OS. The Arden ratio were decreased in electrooculography (EOG) in both patients, and genetic studies revealed a single mutation of the BEST1 gene. The existence of extensive bilateral NSD may be an unusual form of presentation of Best disease. Family history, EOG, and genetic study supported this diagnosis. Copyright © 2018 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

LogMAR and Stereoacuity in Keratoconus Corrected with Spectacles and Rigid Gas-permeable Contact Lenses.

PubMed

Nilagiri, Vinay Kumar; Metlapally, Sangeetha; Kalaiselvan, Parthasarathi; Schor, Clifton M; Bharadwaj, Shrikant R

2018-04-01

This study showed an improvement in three-dimensional depth perception of subjects with bilateral and unilateral keratoconus with rigid gas-permeable (RGP) contact lens wear, relative to spectacles. This novel information will aid clinicians to consider RGP contact lenses as a management modality in keratoconic patients complaining of depth-related difficulties with their spectacles. The aim of this study was to systematically compare changes in logMAR acuity and stereoacuity from best-corrected spherocylindrical spectacles to RGP contact lenses in bilateral and unilateral keratoconus vis-à-vis age-matched control subjects. Monocular and binocular logMAR acuity and random-dot stereoacuity were determined in subjects with bilateral (n = 30; 18 to 24 years) and unilateral (n = 10; 18 to 24 years) keratoconus and 20 control subjects using standard psychophysical protocols. Median (25th to 75th interquartile range) monocular (right eye) and binocular logMAR acuity and stereoacuity improved significantly from spectacles to RGP contact lenses in the bilateral keratoconus cohort (P < .001). Only monocular logMAR acuity of affected eye and stereoacuity improved from spectacles to RGP contact lenses in the unilateral keratoconus cohort (P < .001). There was no significant change in the binocular logMAR acuity from spectacles to RGP contact lenses in the unilateral keratoconus cohort. The magnitude of improvement in binocular logMAR acuity and stereoacuity was also greater for the bilateral compared with the unilateral keratoconus cohort. All outcome measures of cases with RGP contact lenses remained poorer than control subjects (P < .001). Binocular resolution and stereoacuity improve from spectacles to RGP contact lenses in bilateral keratoconus, whereas only stereoacuity improves from spectacles to RGP contact lenses in unilateral keratoconus. The magnitude of improvement in visual performance is greater for the binocular compared with the unilateral keratoconus cohort.

Monkey׳s short-term auditory memory nearly abolished by combined removal of the rostral superior temporal gyrus and rhinal cortices.

PubMed

Fritz, Jonathan B; Malloy, Megan; Mishkin, Mortimer; Saunders, Richard C

2016-06-01

While monkeys easily acquire the rules for performing visual and tactile delayed matching-to-sample, a method for testing recognition memory, they have extraordinary difficulty acquiring a similar rule in audition. Another striking difference between the modalities is that whereas bilateral ablation of the rhinal cortex (RhC) leads to profound impairment in visual and tactile recognition, the same lesion has no detectable effect on auditory recognition memory (Fritz et al., 2005). In our previous study, a mild impairment in auditory memory was obtained following bilateral ablation of the entire medial temporal lobe (MTL), including the RhC, and an equally mild effect was observed after bilateral ablation of the auditory cortical areas in the rostral superior temporal gyrus (rSTG). In order to test the hypothesis that each of these mild impairments was due to partial disconnection of acoustic input to a common target (e.g., the ventromedial prefrontal cortex), in the current study we examined the effects of a more complete auditory disconnection of this common target by combining the removals of both the rSTG and the MTL. We found that the combined lesion led to forgetting thresholds (performance at 75% accuracy) that fell precipitously from the normal retention duration of ~30 to 40s to a duration of ~1 to 2s, thus nearly abolishing auditory recognition memory, and leaving behind only a residual echoic memory. This article is part of a Special Issue entitled SI: Auditory working memory. Published by Elsevier B.V.

A simple behaviour provides accuracy and flexibility in odour plume tracking--the robotic control of sensory-motor coupling in silkmoths.

PubMed

Ando, Noriyasu; Kanzaki, Ryohei

2015-12-01

Odour plume tracking is an essential behaviour for animal survival. A fundamental strategy for this is to move upstream and then across-stream. Male silkmoths, Bombyx mori, display this strategy as a pre-programmed sequential behaviour. They walk forward (surge) in response to the female sex pheromone and perform a zigzagging 'mating dance'. Though pre-programmed, the surge direction is modulated by bilateral olfactory input and optic flow. However, the nature of the interaction between these two sensory modalities and contribution of the resultant motor command to localizing an odour source are still unknown. We evaluated the ability of the silkmoth to localize an odour source under conditions of disturbed sensory-motor coupling, using a silkmoth-driven mobile robot. The significance of the bilateral olfaction of the moth was confirmed by inverting the olfactory input to the antennae, or its motor output. Inversion of the motor output induced consecutive circling, which was inhibited by covering the visual field of the moth. This suggests that the corollary discharge from the motor command and the reafference of self-generated optic flow generate compensatory signals to guide the surge accurately. Additionally, after inverting the olfactory input, the robot successfully tracked the odour plume by using a combination of behaviours. These results indicate that accurate guidance of the reflexive surge by integrating bilateral olfactory and visual information with innate pre-programmed behaviours increases the flexibility to track an odour plume even under disturbed circumstances. © 2015. Published by The Company of Biologists Ltd.

Bilateral Keratoconus Induced by Secondary Hypothyroidism After Radioactive Iodine Therapy.

PubMed

Lee, Ramon; Hafezi, Farhad; Randleman, J Bradley

2018-05-01

To present a case of new-onset, bilateral, rapidly progressive keratoconus induced by secondary hypothyroidism after radioactive iodine therapy during the sixth decade of life that was successfully treated with corneal cross-linking. Case report and literature review. A 53-year-old woman with no ocular complaints but with a history of Graves' disease and thyrotoxicosis was treated with radioactive iodine therapy and oral levothyroxine for secondary acquired hypothyroidism 3 years prior. Initially, uncorrected distance visual acuity (UDVA) was 20/40 and corrected distance visual acuity (CDVA) was 20/25 in both eyes. Over the following 3 years, the patient developed worsening UDVA and CDVA, with increasing manifest astigmatism of greater than 7.00 diopters (D) in the right eye and 4.75 D in the left eye, with corneal thinning and focal steepening and was diagnosed as having bilateral progressive keratoconus. The patient underwent sequential corneal cross-linking with resultant postoperative CDVA of 20/20 and reduced maximum keratometry and manifest astigmatism in both eyes. The patient's thyroid levels were within normal limits throughout the clinical course. This case provides evidence of the relationship between keratoconus development and thyroid gland dysfunction. The pathophysiology of this relationship has yet to be completely elucidated, but elevated levels of thyroxine in the aqueous humor and tear film and thyroxine receptors in the cornea likely play a role. Screening topographies for patients with thyroid gland dysfunction may be of value for these higher risk patients. [J Refract Surg. 2018;34(5):351-353.]. Copyright 2018, SLACK Incorporated.

[Viral cause and management of necrotizing herpetic retinopathies].

PubMed

Tran, T H C; Bodaghi, B; Rozenberg, F; Cassoux, N; Fardeau, C; LeHoang, P

2004-03-01

To study the viral cause and present the management of necrotizing herpetic retinopathies. Charts of patients presenting with acute retinal necrosis (ARN) or progressive outer retinal necrosis (PORN) diagnosed between March 1997 and June 2001 were retrospectively reviewed. Intraocular specimens were obtained in 33 cases to determine the viral cause using polymerase chain reaction-based assays and/or detection of intraocular antibody production. The mean age was 43.4 Years. Herpesvirus genome was identified in 29 patients (80.5%). In the ARN group (32 patients, 38 eyes), herpes simplex virus (HSV) DNA was found in 11 patients (34.4%), varicella-zoster virus (VZV) in nine patients (28.1%), and cytomegalovirus (CMV) in four patients (12.5%). One patient (3.1%) presented an Epstein-Barr virus (EBV) infection. ARN was bilateral at initial examination in six patients and secondary bilateralization was observed in four patients. In the PORN group (four patients, eight eyes), the retinitis was bilateral and VZV DNA was detected in all cases. Two patients were treated with intravenous acyclovir, six with foscarnet alone, ten with intravenous foscarnet + acyclovir, 18 with intravenous foscarnet and intravitreous ganciclovir injections. Complications of necrotizing herpetic retinitis were cataract (26%), optic nerve atrophy (23.9%), and retinal detachment (17.4%). Final visual acuity was less or equal to 20/200 in 47.8% of cases. It is important to determine the specific viral etiology since progression and prognosis may be different in herpetic necrotizing retinitis caused by HSV, VZV, or CMV. Visual prognosis is improved by intensive antiviral therapy, but remains poor if complications occur.

Sensory substitution in bilateral vestibular a-reflexic patients

PubMed Central

Alberts, Bart B G T; Selen, Luc P J; Verhagen, Wim I M; Medendorp, W Pieter

2015-01-01

Patients with bilateral vestibular loss have balance problems in darkness, but maintain spatial orientation rather effectively in the light. It has been suggested that these patients compensate for vestibular cues by relying on extravestibular signals, including visual and somatosensory cues, and integrating them with internal beliefs. How this integration comes about is unknown, but recent literature suggests the healthy brain remaps the various signals into a task-dependent reference frame, thereby weighting them according to their reliability. In this paper, we examined this account in six patients with bilateral vestibular a-reflexia, and compared them to six age-matched healthy controls. Subjects had to report the orientation of their body relative to a reference orientation or the orientation of a flashed luminous line relative to the gravitational vertical, by means of a two-alternative-forced-choice response. We tested both groups psychometrically in upright position (0°) and 90° sideways roll tilt. Perception of body tilt was unbiased in both patients and controls. Response variability, which was larger for 90° tilt, did not differ between groups, indicating that body somatosensory cues have tilt-dependent uncertainty. Perception of the visual vertical was unbiased when upright, but showed systematic undercompensation at 90° tilt. Variability, which was larger for 90° tilt than upright, did not differ between patients and controls. Our results suggest that extravestibular signals substitute for vestibular input in patients’ perception of spatial orientation. This is in line with the current status of rehabilitation programs in acute vestibular patients, targeting at recognizing body somatosensory signals as a reliable replacement for vestibular loss. PMID:25975644

Plasma Concentration of Prolactin, Testosterone Might Be Associated with Brain Response to Visual Erotic Stimuli in Healthy Heterosexual Males

PubMed Central

Seo, Younghee; Kim, Ji-Woong; Choi, Jeewook

2009-01-01

Objective Many studies have showed that excess or lack of sexual hormones, such as prolactin and testosterone, induced the sexual dysfunction in humans. Little, however, is known about the role of sexual hormones showing normal range in, especially, the basal state unexposed to any sexual stimulation. We hypothesized sexual hormones in the basal state may affect sexual behavior. Methods We investigated the association of the sexual hormones level in the basal hormonal state before visual sexual stimulation with the sexual response-related brain activity during the stimulation. Twelve heterosexual men were recorded the functional MRI signals of their brain activation elicited by passive viewing erotic (ERO), happy-faced (HA) couple, food and nature pictures. Both plasma prolacitn and testosterone concentrations were measured before functional MR scanning. A voxel wise regression analyses were performed to investigate the relationship between the concentration of sexual hormones in basal state and brain activity elicited by ERO minus HA, not food minus nature, contrast. Results The plasma concentration of prolactin in basal state showed positive association with the activity of the brain involving cognitive component of sexual behavior including the left middle frontal gyrus, paracingulate/superior frontal/anterior cingulate gyri, bilateral parietal lobule, right angular, bilateral precuneus and right cerebellum. Testosterone in basal state was positively associated with the brain activity of the bilateral supplementary motor area which related with motivational component of sexual behavior. Conclusion Our results suggested sexual hormones in basal state may have their specific target regions or network associated with sexual response. PMID:20046395

Posterior Bilateral Intermuscular Approach for Upper Cervical Spine Injuries.

PubMed

Xu, Yong; Xiong, Wei; Han, Sung I I; Fang, Zhong; Li, Feng

2017-08-01

To investigate a novel intermuscular surgical approach for posterior upper cervical spine fixation. Twenty-three healthy volunteers underwent magnetic resonance imaging. By using the magnetic resonance imaging scans in transverse view at the level of lower edge of atlas, the distances from the posterior midline to lateral margin of trapezius, to the medial margin of splenius capitis, and to middle line of semispinalis capitis were recorded. The angle between posterior middle line and the line crossing the lateral margin of trapezius and middle point of ipsilateral pedicles. From October 2009 to May 2013, 12 patients with upper cervical spine injuries were operated via the bilateral intermuscular approach. The time required for surgery, blood loss, and pre- and postoperative visual analogue scale scores were analyzed. The average distance of 0-T was 39.2 ± 7.5 mm, the angle between the approach and posterior middle line was 33.2 ± 8.4°. The surgical time was 78.3 ± 22.5 minutes (45-140 minutes), and the mean intraoperative blood loss was 87.5 ± 44.2 mL (30-200 mL). Preoperative and postoperative visual analogue scale scores were 6.4 ± 0.8 and 1.8 ± 0.7, respectively. The average follow-up time was 19.7 ± 11.5 months (9-48 months). The posterior bilateral intermuscular approach for upper cervical spine injuries is a valid alternative for Hangmans' fractures type I, type II, and type Ia according to Levine and Edwards classification as well as atlantoaxial subluxation caused by upper cervical spine trauma. Copyright © 2017 Elsevier Inc. All rights reserved.

Bilateral Activity-Dependent Interactions in the Developing Corticospinal System

PubMed Central

Friel, Kathleen M.; Martin, John H.

2009-01-01

Activity-dependent competition between the corticospinal (CS) systems in each hemisphere drives postnatal development of motor skills and stable CS tract connections with contralateral spinal motor circuits. Unilateral restriction of motor cortex (M1) activity during an early postnatal critical period impairs contralateral visually guided movements later in development and in maturity. Silenced M1 develops aberrant connections with the contralateral spinal cord whereas the initially active M1, in the other hemisphere, develops bilateral connections. In this study, we determined whether the aberrant pattern of CS tract terminations and motor impairments produced by early postnatal M1 activity restriction could be abrogated by reducing activity-dependent synaptic competition from the initially active M1 later in development. We first inactivated M1 unilaterally between postnatal weeks 5–7. We next inactivated M1 on the other side from weeks 7–11 (alternate inactivation), to reduce the competitive advantage that this side may have over the initially inactivated side. Alternate inactivation redirected aberrant contralateral CS tract terminations from the initially silenced M1 to their normal spinal territories and reduced the density of aberrant ipsilateral terminations from the initially active side. Normal movement endpoint control during visually guided locomotion was fully restored. This reorganization of CS terminals reveals an unsuspected late plasticity after the critical period for establishing the pattern of CS terminations in the spinal cord. Our findings show that robust bilateral interactions between the developing CS systems on each side are important for achieving balance between contralateral and ipsilateral CS tract connections and visuomotor control. PMID:17928450

Plasma concentration of prolactin, testosterone might be associated with brain response to visual erotic stimuli in healthy heterosexual males.

PubMed

Seo, Younghee; Jeong, Bumseok; Kim, Ji-Woong; Choi, Jeewook

2009-09-01

Many studies have showed that excess or lack of sexual hormones, such as prolactin and testosterone, induced the sexual dysfunction in humans. Little, however, is known about the role of sexual hormones showing normal range in, especially, the basal state unexposed to any sexual stimulation. We hypothesized sexual hormones in the basal state may affect sexual behavior. We investigated the association of the sexual hormones level in the basal hormonal state before visual sexual stimulation with the sexual response-related brain activity during the stimulation. Twelve heterosexual men were recorded the functional MRI signals of their brain activation elicited by passive viewing erotic (ERO), happy-faced (HA) couple, food and nature pictures. Both plasma prolacitn and testosterone concentrations were measured before functional MR scanning. A voxel wise regression analyses were performed to investigate the relationship between the concentration of sexual hormones in basal state and brain activity elicited by ERO minus HA, not food minus nature, contrast. The plasma concentration of prolactin in basal state showed positive association with the activity of the brain involving cognitive component of sexual behavior including the left middle frontal gyrus, paracingulate/superior frontal/anterior cingulate gyri, bilateral parietal lobule, right angular, bilateral precuneus and right cerebellum. Testosterone in basal state was positively associated with the brain activity of the bilateral supplementary motor area which related with motivational component of sexual behavior. Our results suggested sexual hormones in basal state may have their specific target regions or network associated with sexual response.

Children with optic nerve hypoplasia face a high risk of neurodevelopmental disorders.

PubMed

Dahl, Sara; Wickström, Ronny; Ek, Ulla; Teär Fahnehjelm, Kristina

2018-03-01

Optic nerve hypoplasia (ONH) is a congenital ocular malformation that has been associated with neurodevelopmental disorders, but the prevalence in unilateral disease and less severe visual impairment is unknown. We studied intellectual disability and autism spectrum disorders (ASDs) in patients with ONH. This was a population-based cross-sectional cohort study of 65 patients (33 female) with ONH below 20 years of age, living in Stockholm in December 2009, with data analysed in January 2016. Of these 35 were bilateral and 30 were unilateral. Neurodevelopmental disorders were diagnosed or confirmed by neurological assessments, the Five to Fifteen parent questionnaire and reviewing previous neuropsychological investigations or conducting neuropsychological tests. Bilateral ONH patients had lower mean full scale intelligence quotient scores than unilateral patients (84.4 and 99.4, respectively, p = 0.049). We assessed intellectual disability in 55 eligible patients, and it was more common in patients with bilateral ONH (18 of 32, 56%) than unilateral ONH (two of 23, 9%, p < 0.001). ASDs were diagnosed in seven of 42 (17%) patients. Children with bilateral ONH had a high risk of neurodevelopmental disorders, especially intellectual disability. The risk was lower in unilateral ONH, but the levels of neurodevelopmental disorders warrant screening of both groups. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Global processing in amblyopia: a review

PubMed Central

Hamm, Lisa M.; Black, Joanna; Dai, Shuan; Thompson, Benjamin

2014-01-01

Amblyopia is a neurodevelopmental disorder of the visual system that is associated with disrupted binocular vision during early childhood. There is evidence that the effects of amblyopia extend beyond the primary visual cortex to regions of the dorsal and ventral extra-striate visual cortex involved in visual integration. Here, we review the current literature on global processing deficits in observers with either strabismic, anisometropic, or deprivation amblyopia. A range of global processing tasks have been used to investigate the extent of the cortical deficit in amblyopia including: global motion perception, global form perception, face perception, and biological motion. These tasks appear to be differentially affected by amblyopia. In general, observers with unilateral amblyopia appear to show deficits for local spatial processing and global tasks that require the segregation of signal from noise. In bilateral cases, the global processing deficits are exaggerated, and appear to extend to specialized perceptual systems such as those involved in face processing. PMID:24987383

A young woman with visual hallucinations, delusions of persecution and a history of performing arson with possible three-generation Fahr disease.

PubMed

Shirahama, M; Akiyoshi, J; Ishitobi, Y; Tanaka, Y; Tsuru, J; Matsushita, H; Hanada, H; Kodama, K

2010-01-01

Fahr disease (FD) is a rare neurological and psychiatric disorder. The disease is classified by intracranial calcification of the basal ganglia with the globus pallidus region being particularly affected. We examined a young woman with visual hallucinations, delusions of persecution and a history of performing arson with possible third-generation FD. Case report of third-generation FD. A 23-year-old woman was arrested for two arsons: i) The patient exhibited progressive psychotic symptoms, including visual hallucinations, delusion of injury, irritability, lability of mood, mental retardation and visual disorders and ii) Computed tomography (CT) imaging demonstrated bilateral calcifications of the basal ganglia (globus pallidus) in the patient, her mother and her grandmother. We found a family with a three-generation history of FD who exhibited calcification in the brain and mental retardation. Compared to her mother, the patient described here displayed anticipation of disease onset.

[Functional amblyopia].

PubMed

Avram, Elena; Stănilă, Adriana

2013-01-01

Amblyopia is a disorder of the visual system that represents unilateral or bi-lateral reduction of visual acuity in which an organic cause cannot be detected. The illness represents a syndrome of visual deficits, not only a deterioration of visual acuity. This syndrome includes: presence of crowding phenomena, contrast sensitivity deterioration, deficits in accommodation, deterioration of spatial orientation and ocular motility dysfunction. Depending on its etiology, amblyopia is classified into four main types: strabismic amblyopia, anisometropic amblyopia, isoametropic amblyopia and stimulus deprivation amblyopia. To successfully treat the "lazy eye" it is essential to remove the amblyopic factor with techniques addressing each disturbing factor. Techniques used for treating amblyopia include: occlusion, optical penalty or pharmacological, therapy with Levodopa and computer vision therapy. Amblyopia treatment is lengthy and it is very important to counsel not only the child but the whole family and to establish a relationship of trust between doctor and patient in order to get high treatment compliance and high child motivation.

The neuropsychological and neuroradiological correlates of slowly progressive visual agnosia.

PubMed

Giovagnoli, Anna Rita; Aresi, Anna; Reati, Fabiola; Riva, Alice; Gobbo, Clara; Bizzi, Alberto

2009-04-01

The case of a 64-year-old woman affected by slowly progressive visual agnosia is reported aiming to describe specific cognitive-brain relationships. Longitudinal clinical and neuropsychological assessment, combined with magnetic resonance imaging (MRI), spectroscopy, and positron emission tomography (PET) were used. Sequential neuropsychological evaluations performed during a period of 9 years since disease onset showed the appearance of apperceptive and associative visual agnosia, alexia without agraphia, agraphia, finger agnosia, and prosopoagnosia, but excluded dementia. MRI showed moderate diffuse cortical atrophy, with predominant atrophy in the left posterior cortical areas (temporal, parietal, and lateral occipital cortical gyri). 18FDG-PET showed marked bilateral posterior cortical hypometabolism; proton magnetic resonance spectroscopic imaging disclosed severe focal N-acetyl-aspartate depletion in the left temporoparietal and lateral occipital cortical areas. In conclusion, selective metabolic alterations and neuronal loss in the left temporoparietooccipital cortex may determine progressive visual agnosia in the absence of dementia.

Visual Disturbance as the first Symptom of Chronic Myeloid Leukemia

PubMed Central

Huang, Philemon K.; Sanjay, Srinivasan

2011-01-01

Chronic myeloid leukemia (CML) is a well-studied entity and advances made in diagnosis and treatment have improved the disease outcome. Patients with ophthalmic manifestation of CML have been reported to have lower 5-year survival rates. Hence, recognizing the early fundus changes may improve outcome by allowing earlier diagnosis and treatment. We report a case of a previously healthy 30-year-old Myanmarese male, who presented with a minor visual disturbance, complaining of seeing a ‘black dot’ in his left visual field for the past 1 week. Fundoscopic examination revealed bilateral retinal blot hemorrhages, white-centered hemorrhage, and preretinal hemorrhage over the left fovea. The full blood count and peripheral blood film were abnormal, and bone marrow biopsy confirmed the diagnosis of CML. Cytoreduction therapy was promptly commenced and his symptoms resolved, with improvement in visual acuity. No complications were recorded at 1-year follow-up. PMID:22224030

Visual Disturbance as the first Symptom of Chronic Myeloid Leukemia.

PubMed

Huang, Philemon K; Sanjay, Srinivasan

2011-10-01

Chronic myeloid leukemia (CML) is a well-studied entity and advances made in diagnosis and treatment have improved the disease outcome. Patients with ophthalmic manifestation of CML have been reported to have lower 5-year survival rates. Hence, recognizing the early fundus changes may improve outcome by allowing earlier diagnosis and treatment. We report a case of a previously healthy 30-year-old Myanmarese male, who presented with a minor visual disturbance, complaining of seeing a 'black dot' in his left visual field for the past 1 week. Fundoscopic examination revealed bilateral retinal blot hemorrhages, white-centered hemorrhage, and preretinal hemorrhage over the left fovea. The full blood count and peripheral blood film were abnormal, and bone marrow biopsy confirmed the diagnosis of CML. Cytoreduction therapy was promptly commenced and his symptoms resolved, with improvement in visual acuity. No complications were recorded at 1-year follow-up.

Semantically induced distortions of visual awareness in a patient with Balint's syndrome.

PubMed

Soto, David; Humphreys, Glyn W

2009-02-01

We present data indicating that visual awareness for a basic perceptual feature (colour) can be influenced by the relation between the feature and the semantic properties of the stimulus. We examined semantic interference from the meaning of a colour word (''RED") on simple colour (ink related) detection responses in a patient with simultagnosia due to bilateral parietal lesions. We found that colour detection was influenced by the congruency between the meaning of the word and the relevant ink colour, with impaired performance when the word and the colour mismatched (on incongruent trials). This result held even when remote associations between meaning and colour were used (i.e. the word ''PEA" influenced detection of the ink colour red). The results are consistent with a late locus of conscious visual experience that is derived at post-semantic levels. The implications for the understanding of the role of parietal cortex in object binding and visual awareness are discussed.

Altered resting-state functional connectivity in patients with chronic bilateral vestibular failure.

PubMed

Göttlich, Martin; Jandl, Nico M; Wojak, Jann F; Sprenger, Andreas; von der Gablentz, Janina; Münte, Thomas F; Krämer, Ulrike M; Helmchen, Christoph

2014-01-01

Patients with bilateral vestibular failure (BVF) suffer from gait unsteadiness, oscillopsia and impaired spatial orientation. Brain imaging studies applying caloric irrigation to patients with BVF have shown altered neural activity of cortical visual-vestibular interaction: decreased bilateral neural activity in the posterior insula and parietal operculum and decreased deactivations in the visual cortex. It is unknown how this affects functional connectivity in the resting brain and how changes in connectivity are related to vestibular impairment. We applied a novel data driven approach based on graph theory to investigate altered whole-brain resting-state functional connectivity in BVF patients (n= 22) compared to age- and gender-matched healthy controls (n= 25) using resting-state fMRI. Changes in functional connectivity were related to subjective (vestibular scores) and objective functional parameters of vestibular impairment, specifically, the adaptive changes during active (self-guided) and passive (investigator driven) head impulse test (HIT) which reflects the integrity of the vestibulo-ocular reflex (VOR). BVF patients showed lower bilateral connectivity in the posterior insula and parietal operculum but higher connectivity in the posterior cerebellum compared to controls. Seed-based analysis revealed stronger connectivity from the right posterior insula to the precuneus, anterior insula, anterior cingulate cortex and the middle frontal gyrus. Excitingly, functional connectivity in the supramarginal gyrus (SMG) of the inferior parietal lobe and posterior cerebellum correlated with the increase of VOR gain during active as compared to passive HIT, i.e., the larger the adaptive VOR changes the larger was the increase in regional functional connectivity. Using whole brain resting-state connectivity analysis in BVF patients we show that enduring bilateral deficient or missing vestibular input leads to changes in resting-state connectivity of the brain. These changes in the resting brain are robust and task-independent as they were found in the absence of sensory stimulation and without a region-related a priori hypothesis. Therefore they may indicate a fundamental disease-related change in the resting brain. They may account for the patients' persistent deficits in visuo-spatial attention, spatial orientation and unsteadiness. The relation of increasing connectivity in the inferior parietal lobe, specifically SMG, to improvement of VOR during active head movements reflects cortical plasticity in BVF and may play a clinical role in vestibular rehabilitation.

Higher integrity of the motor and visual pathways in long-term video game players.

PubMed

Zhang, Yang; Du, Guijin; Yang, Yongxin; Qin, Wen; Li, Xiaodong; Zhang, Quan

2015-01-01

Long term video game players (VGPs) exhibit superior visual and motor skills compared with non-video game control subjects (NVGCs). However, the neural basis underlying the enhanced behavioral performance remains largely unknown. To clarify this issue, the present study compared the whiter matter integrity within the corticospinal tracts (CST), the superior longitudinal fasciculus (SLF), the inferior longitudinal fasciculus (ILF), and the inferior fronto-occipital fasciculus (IFOF) between the VGPs and the NVGCs using diffusion tensor imaging. Compared with the NVGCs, voxel-wise comparisons revealed significantly higher fractional anisotropy (FA) values in some regions within the left CST, left SLF, bilateral ILF, and IFOF in VGPs. Furthermore, higher FA values in the left CST at the level of cerebral peduncle predicted a faster response in visual attention tasks. These results suggest that higher white matter integrity in the motor and higher-tier visual pathways is associated with long-term video game playing, which may contribute to the understanding on how video game play influences motor and visual performance.

Higher integrity of the motor and visual pathways in long-term video game players

PubMed Central

Du, Guijin; Yang, Yongxin; Qin, Wen; Li, Xiaodong; Zhang, Quan

2015-01-01

Long term video game players (VGPs) exhibit superior visual and motor skills compared with non-video game control subjects (NVGCs). However, the neural basis underlying the enhanced behavioral performance remains largely unknown. To clarify this issue, the present study compared the whiter matter integrity within the corticospinal tracts (CST), the superior longitudinal fasciculus (SLF), the inferior longitudinal fasciculus (ILF), and the inferior fronto-occipital fasciculus (IFOF) between the VGPs and the NVGCs using diffusion tensor imaging. Compared with the NVGCs, voxel-wise comparisons revealed significantly higher fractional anisotropy (FA) values in some regions within the left CST, left SLF, bilateral ILF, and IFOF in VGPs. Furthermore, higher FA values in the left CST at the level of cerebral peduncle predicted a faster response in visual attention tasks. These results suggest that higher white matter integrity in the motor and higher-tier visual pathways is associated with long-term video game playing, which may contribute to the understanding on how video game play influences motor and visual performance. PMID:25805981

Residual perception of biological motion in cortical blindness.

PubMed

Ruffieux, Nicolas; Ramon, Meike; Lao, Junpeng; Colombo, Françoise; Stacchi, Lisa; Borruat, François-Xavier; Accolla, Ettore; Annoni, Jean-Marie; Caldara, Roberto

2016-12-01

From birth, the human visual system shows a remarkable sensitivity for perceiving biological motion. This visual ability relies on a distributed network of brain regions and can be preserved even after damage of high-level ventral visual areas. However, it remains unknown whether this critical biological skill can withstand the loss of vision following bilateral striate damage. To address this question, we tested the categorization of human and animal biological motion in BC, a rare case of cortical blindness after anoxia-induced bilateral striate damage. The severity of his impairment, encompassing various aspects of vision (i.e., color, shape, face, and object recognition) and causing blind-like behavior, contrasts with a residual ability to process motion. We presented BC with static or dynamic point-light displays (PLDs) of human or animal walkers. These stimuli were presented either individually, or in pairs in two alternative forced choice (2AFC) tasks. When confronted with individual PLDs, the patient was unable to categorize the stimuli, irrespective of whether they were static or dynamic. In the 2AFC task, BC exhibited appropriate eye movements towards diagnostic information, but performed at chance level with static PLDs, in stark contrast to his ability to efficiently categorize dynamic biological agents. This striking ability to categorize biological motion provided top-down information is important for at least two reasons. Firstly, it emphasizes the importance of assessing patients' (visual) abilities across a range of task constraints, which can reveal potential residual abilities that may in turn represent a key feature for patient rehabilitation. Finally, our findings reinforce the view that the neural network processing biological motion can efficiently operate despite severely impaired low-level vision, positing our natural predisposition for processing dynamicity in biological agents as a robust feature of human vision. Copyright © 2016 Elsevier Ltd. All rights reserved.

Reading Embossed Capital Letters: An fMRI Study in Blind and Sighted Individuals

PubMed Central

Burton, H.; McLaren, D.G.; Sinclair, R.J.

2013-01-01

Reading Braille activates visual cortex in blind people [Burton et al., J Neurophysiol 2002;87: 589-611; Sadato et al., Nature 1996;380:526-528; Sadato et al., Brain 1998;121:1213-1229]. Because learning Braille requires extensive training, we had sighted and blind people read raised block capital letters to determine whether all groups engage visual cortex similarly when reading by touch. Letters were passively rubbed across the right index finger at 30 mm/s using an MR-compatible drum stimulator. Age-matched sighted, early blind (lost sight 0–5 years), and late blind (lost sight >5.5 years) volunteers performed three tasks: stating an identified letter, stating a verb containing an identified letter, and feeling a moving smooth surface. Responses were voiced immediately after the drum stopped moving across the fingertip. All groups showed increased activity in visual areas V1 and V2 during both letter identification tasks. Blind compared to sighted participants showed greater activation increases predominantly in the parafoveal-peripheral portions of visuotopic areas and posterior parts of BA 20 and 37. Sighted participants showed suppressed activity in most of the same areas except for small positive responses bilaterally in V1, left V5/MT+, and bilaterally in BA 37/20. Blind individuals showed suppression of the language areas in the frontal cortex, while sighted individuals showed slight positive responses. Early blind showed a more extensive distribution of activity in superior temporal sulcal multisensory areas. These results show cross-modal reorganization of visual cortex and altered response dynamics in nonvisual areas that plausibly reflect mechanisms for adaptive plasticity in blindness. PMID:16142777

Long term outcomes of bilateral congenital and developmental cataracts operated in Maharashtra, India. Miraj pediatric cataract study III.

PubMed

Gogate, Parikshit M; Sahasrabudhe, Mohini; Shah, Mitali; Patil, Shailbala; Kulkarni, Anil N; Trivedi, Rupal; Bhasa, Divya; Tamboli, Rahin; Mane, Rekha

2014-02-01

To study long term outcome of bilateral congenital and developmental cataract surgery. 258 pediatric cataract operated eyes of 129 children. Children who underwent pediatric cataract surgery in 2004-8 were traced and examined prospectively in 2010-11. Demographic and clinical factors were noted from retrospective chart readings. All children underwent visual acuity estimation and comprehensive ocular examination in a standardized manner. L. V. Prasad Child Vision Function scores (LVP-CVF) were noted for before and after surgery. Statistical analysis was done with SPSS version 16 including multi-variate analysis. Children aged 9.1 years (std dev 4.6, range 7 weeks-15 years) at the time of surgery. 74/129 (57.4%) were boys. The average duration of follow-up was 4.4 years (stddev 1.6, range 3-8 years). 177 (68.6%) eyes had vision <3/60 before surgery, while 109 (42.2%) had best corrected visual acuity (BCVA) >6/18 and 157 (60.9%) had BCVA >6/60 3-8 years after surgery. 48 (37.2%) had binocular stereoacuity <480 sec of arc by TNO test. Visual outcome depended on type of cataract (P = 0.004), type of cataract surgery (P < 0.001), type of intra-ocular lens (P = 0.05), age at surgery (P = 0.004), absence of post-operative uveitis (P = 0.01) and pre-operative vision (P < 0.001), but did not depend on delay (0.612) between diagnosis and surgery. There was a statistically significant improvement for all the 20 questions of the LVP-CVF scale (P < 0.001). Pediatric cataract surgery improved the children's visual acuity, stereo acuity and vision function. Developmental cataract, use of phacoemulsification, older children and those with better pre-operative vision had betterlong-termoutcomes.

Severity of Visual Field Loss and Health Related Quality of Life

PubMed Central

McKean-Cowdin, Roberta; Varma, Rohit; Wu, Joanne; Hays, Ron D.; Azen, Stanley P.

2009-01-01

Purpose To examine the association between severity of visual field loss (VFL) and self-reported health-related quality of life (HRQOL) in a population-based sample. Design Population-based cross-sectional study. Methods Participants in the Los Angeles Latino Eye Study underwent a comprehensive ophthalmic examination including visual field testing using the Humphrey Automated Field Analyzer II (SITA Standard 24-2). Mean Deviation (MD) scores were used to determine severity of VFL both as a continuous variable and stratified by severity: no VFL (MD≥ − 2 decibels [dB]), mild VFL (6dB

Altered cerebral hemodyamics and cortical thinning in asymptomatic carotid artery stenosis.

PubMed

Marshall, Randolph S; Asllani, Iris; Pavol, Marykay A; Cheung, Ying-Kuen; Lazar, Ronald M

2017-01-01

Cortical thinning is a potentially important biomarker, but the pathophysiology in cerebrovascular disease is unknown. We investigated the association between regional cortical blood flow and regional cortical thickness in patients with asymptomatic unilateral high-grade internal carotid artery disease without stroke. Twenty-nine patients underwent high resolution anatomical and single-delay, pseudocontinuous arterial spin labeling magnetic resonance imaging with partial volume correction to assess gray matter baseline flow. Cortical thickness was estimated using Freesurfer software, followed by co-registration onto each patient's cerebral blood flow image space. Paired t-tests assessed regional cerebral blood flow in motor cortex (supplied by the carotid artery) and visual cortex (indirectly supplied by the carotid) on the occluded and unoccluded side. Pearson correlations were calculated between cortical thickness and regional cerebral blood flow, along with age, hypertension, diabetes and white matter hyperintensity volume. Multiple regression and generalized estimating equation were used to predict cortical thickness bilaterally and in each hemisphere separately. Cortical blood flow correlated with thickness in motor cortex bilaterally (p = 0.0002), and in the occluded and unoccluded sides individually; age (p = 0.002) was also a predictor of cortical thickness in the motor cortex. None of the variables predicted cortical thickness in visual cortex. Blood flow was significantly lower on the occluded versus unoccluded side in the motor cortex (p<0.0001) and in the visual cortex (p = 0.018). On average, cortex was thinner on the side of occlusion in motor but not in visual cortex. The association between cortical blood flow and cortical thickness in carotid arterial territory with greater thinning on the side of the carotid occlusion suggests that altered cerebral hemodynamics is a factor in cortical thinning.

Trends in Visual Health Inequalities in Childhood Through Associations of Visual Function With Sex and Social Position Across 3 UK Birth Cohorts.

PubMed

Bountziouka, Vasiliki; Cumberland, Phillippa M; Rahi, Jugnoo S

2017-09-01

Despite the existing country-specific strategies tackling social inequalities in visual health in adults, little is known about trends in visual function in childhood and its association with social position. To investigate the distribution of childhood visual function in the United Kingdom and associations with early-life social position between 1961 and 1986, a period of significant social change. Longitudinal cohort study using harmonized data sets from the British 1946, 1958, and 1970 national birth cohorts. In total, 14 283 cohort members with complete data on visual acuity at age 15 or 16 years, measured in 1961, 1974, and 1986, respectively, for each cohort, and social position were assessed. Using habitual distance visual acuity (with correction if prescribed), participants were assigned to a visual function category ranging from bilateral normal to visual impairment/severe visual impairment/blindness (International Statistical Classification of Diseases, Tenth Revision, Clinical Modification). Distribution of visual function over time and associations with social position (risk ratios [RRs] and 95% confidence intervals) were analyzed. Complete data were available for 3152 participants (aged 15 years; 53% boys [n = 1660]) in the 1946 Medical Research Council National Survey of Health and Development, 6683 participants (aged 16 years; 51% boys [n = 3420]) in the 1958 National Child Development Study, and 4448 participants (aged 16 years; 48% boys [n = 2156]) in the 1970 British Birth Cohort Study. The proportion of children with bilateral normal vision decreased by 1.3% (95% CI, -5.1% to 2.7%) in 1974 and 1.7% (95% CI, -5.9% to 2.7%) in 1986. The risk of overall impaired vision increased by 1.20 times (95% CI, 1.01-1.43) and the risk of visual impairment/severe visual impairment/blindness by 1.75 times (95% CI, 1.03-2.98) during this period. Girls were consistently at increased risk of all vision impairment categories. Higher social position at birth and in childhood was associated with reduced risk of visual impairment/severe visual impairment/blindness (RR, 0.58; 95% CI, 0.20-1.68) and unilateral impairment (RR, 0.89; 95% CI, 0.72-1.11), respectively. Our study provides evidence of temporal decline in childhood visual function between 1961 and 1986. Despite the limited power of the analysis owing to the small sample size of those with impaired vision, we found an emergence of a contribution of sociodemographic status to the cohort effect that may be the antecedent of the current picture of childhood blindness. Equally, early-life social position may also have contributed to the current social patterning in visual function in older adults in the United Kingdom. These findings highlight the potential value of targeting children in national ophthalmic public policies tackling inequalities.

Colateralization of Broca's Area and the Visual Word form Area in Left-Handers: fMRI Evidence

ERIC Educational Resources Information Center

Van der Haegen, Lise; Cai, Qing; Brysbaert, Marc

2012-01-01

Language production has been found to be lateralized in the left hemisphere (LH) for 95% of right-handed people and about 75% of left-handers. The prevalence of atypical right hemispheric (RH) or bilateral lateralization for reading and colateralization of production with word reading laterality has never been tested in a large sample. In this…

Perceptual-Attentional and Motor-Intentional Bias in Near and Far Space

PubMed Central

Garza, John P.; Eslinger, Paul J.; Barrett, Anna M.

2008-01-01

Spatial bias demonstrated in tasks such as line-bisection may stem from perceptual-attentional (PA) “where” and motor-intentional (MI) “aiming” influences. We tested normal participants’ line bisection performance in the presence of an asymmetric visual distracter with a video apparatus designed to dissociate PA from MI bias. An experimenter stood as a distractor to the left or right of a video monitor positioned in either near or far space, where participants viewed lines and a laser point they directed under 1) natural and 2) mirror-reversed conditions. Each trial started with the pointer positioned at either the top left or top right corner of the screen, and alternated thereafter. Data analysis indicated that participants made primarily PA leftward errors in near space, but not in far space. Furthermore, PA, but not MI, bias increased bilaterally in the direction of distraction. In contrast, MI, but not PA, bias was shifted bilaterally in the direction of startside. Results support the conclusion that a primarily PA left sided bias in near space is consistent with right hemisphere spatial attentional dominance. A bottom-up visual distractor specifically affected PA “where” spatial bias while top-down motor cuing influenced MI “aiming” bias. PMID:18381226

Separating neural activity associated with emotion and implied motion: An fMRI study.

PubMed

Kolesar, Tiffany A; Kornelsen, Jennifer; Smith, Stephen D

2017-02-01

Previous research provides evidence for an emo-motoric neural network allowing emotion to modulate activity in regions of the nervous system related to movement. However, recent research suggests that these results may be due to the movement depicted in the stimuli. The purpose of the current study was to differentiate the unique neural activity of emotion and implied motion using functional MRI. Thirteen healthy participants viewed 4 sets of images: (a) negative stimuli implying movement, (b) negative stimuli not implying movement, (c) neutral stimuli implying movement, and (d) neutral stimuli not implying movement. A main effect for implied motion was found, primarily in regions associated with multimodal integration (bilateral insula and cingulate), and visual areas that process motion (bilateral middle temporal gyrus). A main effect for emotion was found primarily in occipital and parietal regions, indicating that emotion enhances visual perception. Surprisingly, emotion also activated the left precentral gyrus, a motor region. These results demonstrate that emotion elicits activity above and beyond that evoked by the perception of implied movement, but that the neural representations of these characteristics overlap. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Navigation ability dependent neural activation in the human brain: an fMRI study.

PubMed

Ohnishi, Takashi; Matsuda, Hiroshi; Hirakata, Makiko; Ugawa, Yoshikazu

2006-08-01

Visual-spatial navigation in familiar and unfamiliar environments is an essential requirement of daily life. Animal studies indicated the importance of the hippocampus for navigation. Neuroimaging studies demonstrated gender difference or strategies dependent difference of neural substrates for navigation. Using functional magnetic resonance imaging, we measured brain activity related to navigation in four groups of normal volunteers: good navigators (males and females) and poor navigators (males and females). In a whole group analysis, task related activity was noted in the hippocampus, parahippocampal gyrus, posterior cingulate cortex, precuneus, parietal association areas, and the visual association areas. In group comparisons, good navigators showed a stronger activation in the medial temporal area and precuneus than poor navigators. There was neither sex effect nor interaction effect between sex and navigation ability. The activity in the left medial temporal areas was positively correlated with task performance, whereas activity in the right parietal area was negatively correlated with task performance. Furthermore, the activity in the bilateral medial temporal areas was positively correlated with scores reflecting preferred navigation strategies, whereas activity in the bilateral superior parietal lobules was negatively correlated with them. Our data suggest that different brain activities related to navigation should reflect navigation skill and strategies.

Intrinsically organized network for word processing during the resting state.

PubMed

Zhao, Jizheng; Liu, Jiangang; Li, Jun; Liang, Jimin; Feng, Lu; Ai, Lin; Lee, Kang; Tian, Jie

2011-01-03

Neural mechanisms underlying word processing have been extensively studied. It has been revealed that when individuals are engaged in active word processing, a complex network of cortical regions is activated. However, it is entirely unknown whether the word-processing regions are intrinsically organized without any explicit processing tasks during the resting state. The present study investigated the intrinsic functional connectivity between word-processing regions during the resting state with the use of fMRI methodology. The low-frequency fluctuations were observed between the left middle fusiform gyrus and a number of cortical regions. They included the left angular gyrus, left supramarginal gyrus, bilateral pars opercularis, and left pars triangularis of the inferior frontal gyrus, which have been implicated in phonological and semantic processing. Additionally, the activations were also observed in the bilateral superior parietal lobule and dorsal lateral prefrontal cortex, which have been suggested to provide top-down monitoring on the visual-spatial processing of words. The findings of our study indicate an intrinsically organized network during the resting state that likely prepares the visual system to anticipate the highly probable word input for ready and effective processing. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Gender similarities and differences in brain activation strategies: Voxel-based meta-analysis on fMRI studies.

PubMed

AlRyalat, Saif Aldeen

2017-01-01

Gender similarities and differences have long been a matter of debate in almost all human research, especially upon reaching the discussion about brain functions. This large scale meta-analysis was performed on functional MRI studies. It included more than 700 active brain foci from more than 70 different experiments to study gender related similarities and differences in brain activation strategies for three of the main brain functions: Visual-spatial cognition, memory, and emotion. Areas that are significantly activated by both genders (i.e. core areas) for the tested brain function are mentioned, whereas those areas significantly activated exclusively in one gender are the gender specific areas. During visual-spatial cognition task, and in addition to the core areas, males significantly activated their left superior frontal gyrus, compared with left superior parietal lobule in females. For memory tasks, several different brain areas activated by each gender, but females significantly activated two areas from the limbic system during memory retrieval tasks. For emotional task, males tend to recruit their bilateral prefrontal regions, whereas females tend to recruit their bilateral amygdalae. This meta-analysis provides an overview based on functional MRI studies on how males and females use their brain.

[Neuroretinitis. Clinical cases].

PubMed

Valverde-Gubianas, M; Ramos-López, J F; López-Torres, J A; Toribio-García, M; Milla-Peñalver, C; Gálvez Torres-Puchol, J; Medialdea-Marcos, S

2009-08-01

Evaluate the etiology and the most frequent funduscopic alterations of the neuroretinitis. We present the case of a woman 24 years old with a bilateral decrease of visual sharpness (AV), painless and progressive, the funduscopic examination of which reveals a bilateral optical disc edema, with no hemorrhages or exudates, retina edema of the posterior pole and phlebitic areas. The systematic study was normal except for the hemogram (18,000/mm(3) leucocytes with 79% neutrophils) and the positive serology next to a Chlamydia. We also present the case of a 64 years old woman with a decrease of AV at the right eye of one week duration. At the back of the eye a macular star can be seen, and papilla edema. A systematic study gave normal results and positive serology at Bartonella henselae. The illness produced by a cat scratch is the most common cause of neuroretinitis. The customary findings are a loss of AV, discromatopsia, afferent papillary defects and abnormality on the visual field. Other frequent findings at the back of the eye are hemorrhagic nerve fibers, cotton-like exudates, papilla edema, macular star and glassy inflammation. The roll of antibiotic therapy is questionable. Oral ciprofloxacine seems to give good results.

Local Immediate versus Long-Range Delayed Changes in Functional Connectivity Following rTMS on the Visual Attention Network.

PubMed

Battelli, Lorella; Grossman, Emily D; Plow, Ela B

The interhemispheric competition hypothesis attributes the distribution of selective attention to a balance of mutual inhibition between homotopic, interhemispheric connections in parietal cortex (Kinsbourne 1977; Battelli et al., 2009). In support of this hypothesis, repetitive inhibitory TMS over right parietal cortex in healthy individuals rapidly induces interhemispheric imbalance in cortical activity that spreads beyond the site of stimulation (Plow et al., 2014). Behaviorally, the impacts of inhibitory rTMS may be long delayed from the onset of stimulation, as much as 30 minutes (Agosta et al., 2014; Hubl et al., 2008). In this study, we examine the temporal dynamics of inhibitory rTMS on cortical network integrity that supports sustained visual attention. Healthy individuals received 15 min of 1 Hz offline, inhibitory rTMS (or sham) over left parietal cortex, and then immediately engaged in a bilateral visual tracking task while we recorded brain activity with fMRI. We computed functional connectivity (FC) between three nodes of the attention network engaged by visual tracking: the intraparietal sulcus (IPS), frontal eye fields (FEF) and human MT+ (hMT+). FC immediately and significantly decreased between the stimulation site (left IPS) and all other regions, then recovered to normal levels within 30 minutes. rTMS increased FC between left and right FEF at approximately 36 min following stimulation, and between sites in the unstimulated hemisphere approximately 48 min after stimulation. These findings demonstrate large-scale changes in cortical organization following inhibitory rTMS. The immediate impact of rTMS on connectivity to the stimulation site dovetails with the putative role of interhemispheric balance for bilateral visual sustained attention. The delayed, compensatory increases in functional connectivity have implications for models of dynamic reorganization in networks supporting spatial and nonspatial selective attention, and compensatory mechanisms within these networks that may be stabilized in chronic stroke. Copyright © 2016 Elsevier Inc. All rights reserved.

Do older drivers with bilateral cataract self-regulate their driving while waiting for first eye cataract surgery?

PubMed Central

Agramunt, Seraina; Meuleners, Lynn B; Fraser, Michelle L; Chow, Kyle C; Ng, Jonathon Q; Raja, Vignesh; Morlet, Nigel

2017-01-01

Objectives To analyze the association between visual impairment and driver self-regulation among a cohort of older drivers waiting for first eye cataract surgery. Methods Ninety-six drivers with bilateral cataract aged 55+ years were assessed before first eye cataract surgery. Data collection consisted of a researcher-administered questionnaire, objective visual measures (visual acuity, contrast sensitivity and stereopsis), a visual attention test (the useful field of view test) and a cognitive test (the Mini-Mental State Examination). Driver self-regulation practices were collected using the Driving Habits Questionnaire and were also measured with an in-vehicle monitoring device. Characteristics of self-regulators and non-self-regulators were compared and a logistic regression model was used to examine the association between 3 objective visual measures and driver self-regulation status. Results After controlling for potential confounding factors, only binocular contrast sensitivity (p=0.01), age (p=0.03) and gender (p=0.03) were significantly associated with driver self-regulation status. The odds of participants with better contrast sensitivity scores (better vision) self-regulating their driving in at least 1 driving situation decreased (odds ratio [OR]: 0.01, 95% CI: 0.00–0.28) while those of increasing age reported an increased odds of self-regulating their driving (OR: 1.08, 95% CI: 1.01–1.15). The odds of males self-regulating their driving was decreased compared with females (OR: 0.28, 95% CI: 0.09–0.86). Conclusions Worse binocular contrast sensitivity scores, increasing age and being female were significantly associated with driver self-regulation. The study highlighted that while self-regulation was common among cataract patients, a proportion of those with poor vision did not self-regulate. Further research should determine how cataract patients could benefit from self-regulation strategies while waiting for cataract surgery. PMID:29184397

Effects of deuterium oxide and galvanic vestibular stimulation on visual cortical cell function

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reinis, S.; Landolt, J.P.; Weiss, D.S.

1984-03-01

The spontaneous and evoked unit activities of complex visual cortical cells were recorded from Brodmann's area 18 in immobilized, unanesthetized cats before, during, and after stimulation of the vestibular system. The vestibular system was stimulated by intravenous injection of deuterium oxide (D2O)--a noted nystagmogenic agent--or by direct galvanic stimulation of the labyrinth. Measures of the receptive-field areas, poststimulus time histograms, directional preferences, and the optimal speed of the light bar stimulating the cell were obtained before and after the application of D2O. Directional preferences were determined in a novel manner, using a method derived from a hierarchical clustering technique. Datamore » were collected and analyzed from a) visual cortical cells in cats with intact labyrinths, b) visual cortical cells in cats following bilateral labrinthectomies, and c) nonvisual cortical cells in cats with intact labyrinths. The other cellular characteristics were also altered by the D2O. Galvanic stimulation of the labyrinth resembles, in its effects, the injection of D2O. In labyrinth-intact cats, the time course of area 18 spontaneous activity dramatically increased 30 min or more after D2O was administered. It peaked 2-3 h later and still had not returned to preinjection levels even 7 h after the D2O administration. In bilaterally labyrinthectomized cats, the spontaneous activity of the visual cells did not change following D2O administration. In nonvisual cells from labyrinth-intact cats, the spontaneous activity demonstrated a slight but significant decrease over time after D2O injection. In pilot studies, the cats were injected with D2O. Within 8-10 min afterward, signs of positional nystagmus commenced; and within 30 min, problems in maintaining balance were noted. This continued for 7-8 h before disappearing. In the labyrinthectomized animals, such effects were not observed.« less

Kinesthetic motor imagery modulates body sway.

PubMed

Rodrigues, E C; Lemos, T; Gouvea, B; Volchan, E; Imbiriba, L A; Vargas, C D

2010-08-25

The aim of this study was to investigate the effect of imagining an action implicating the body axis in the kinesthetic and visual motor imagery modalities upon the balance control system. Body sway analysis (measurement of center of pressure, CoP) together with electromyography (EMG) recording and verbal evaluation of imagery abilities were obtained from subjects during four tasks, performed in the upright position: to execute bilateral plantar flexions; to imagine themselves executing bilateral plantar flexions (kinesthetic modality); to imagine someone else executing the same movement (visual modality), and to imagine themselves singing a song (as a control imagery task). Body sway analysis revealed that kinesthetic imagery leads to a general increase in CoP oscillation, as reflected by an enhanced area of displacement. This effect was also verified for the CoP standard deviation in the medial-lateral direction. An increase in the trembling displacement (equivalent to center of pressure minus center of gravity) restricted to the anterior-posterior direction was also observed to occur during kinesthetic imagery. The visual imagery task did not differ from the control (sing) task for any of the analyzed parameters. No difference in the subjects' ability to perform the imagery tasks was found. No modulation of EMG data were observed across imagery tasks, indicating that there was no actual execution during motor imagination. These results suggest that motor imagery performed in the kinesthetic modality evokes motor representations involved in balance control. Copyright (c)10 IBRO. Published by Elsevier Ltd. All rights reserved.

Neurochemical changes in the pericalcarine cortex in congenital blindness attributable to bilateral anophthalmia.

PubMed

Coullon, Gaelle S L; Emir, Uzay E; Fine, Ione; Watkins, Kate E; Bridge, Holly

2015-09-01

Congenital blindness leads to large-scale functional and structural reorganization in the occipital cortex, but relatively little is known about the neurochemical changes underlying this cross-modal plasticity. To investigate the effect of complete and early visual deafferentation on the concentration of metabolites in the pericalcarine cortex, (1)H magnetic resonance spectroscopy was performed in 14 sighted subjects and 5 subjects with bilateral anophthalmia, a condition in which both eyes fail to develop. In the pericalcarine cortex, where primary visual cortex is normally located, the proportion of gray matter was significantly greater, and levels of choline, glutamate, glutamine, myo-inositol, and total creatine were elevated in anophthalmic relative to sighted subjects. Anophthalmia had no effect on the structure or neurochemistry of a sensorimotor cortex control region. More gray matter, combined with high levels of choline and myo-inositol, resembles the profile of the cortex at birth and suggests that the lack of visual input from the eyes might have delayed or arrested the maturation of this cortical region. High levels of choline and glutamate/glutamine are consistent with enhanced excitatory circuits in the anophthalmic occipital cortex, which could reflect a shift toward enhanced plasticity or sensitivity that could in turn mediate or unmask cross-modal responses. Finally, it is possible that the change in function of the occipital cortex results in biochemical profiles that resemble those of auditory, language, or somatosensory cortex. Copyright © 2015 the American Physiological Society.

Visualization of nigrosome 1 and its loss in PD

PubMed Central

Schwarz, Stefan T.; Pitiot, Alain; Stephenson, Mary C.; Lowe, James; Bajaj, Nin; Bowtell, Richard W.; Auer, Dorothee P.; Gowland, Penny A.

2013-01-01

Objective: This study assessed whether high-resolution 7 T MRI allowed direct in vivo visualization of nigrosomes, substructures of the substantia nigra pars compacta (SNpc) undergoing the greatest and earliest dopaminergic cell loss in Parkinson disease (PD), and whether any disease-specific changes could be detected in patients with PD. Methods: Postmortem (PM) midbrains, 2 from healthy controls (HCs) and 1 from a patient with PD, were scanned with high-resolution T2*-weighted MRI scans, sectioned, and stained for iron and neuromelanin (Perl), TH, and calbindin. To confirm the identification of nigrosomes in vivo on 7 T T2*-weighted scans, we assessed colocalization with neuromelanin-sensitive T1-weighted scans. We then assessed the ability to depict PD pathology on in vivo T2*-weighted scans by comparing data from 10 patients with PD and 8 age- and sex-matched HCs. Results: A hyperintense, ovoid area within the dorsolateral border of the otherwise hypointense SNpc was identified in the HC brains on in vivo and PM T2*-weighted MRI. Location, size, shape, and staining characteristics conform to nigrosome 1. Blinded assessment by 2 neuroradiologists showed consistent bilateral absence of this nigrosome feature in all 10 patients with PD, and bilateral presence in 7/8 HC. Conclusions: In vivo and PM MRI with histologic correlation demonstrates that high-resolution 7 T MRI can directly visualize nigrosome 1. The absence of nigrosome 1 in the SNpc on MRI scans might prove useful in developing a neuroimaging diagnostic test for PD. PMID:23843466

Analysis of 777 cases with obstruction of the ureter or extrahepatic bile duct by ultrasonography after normal saline retention enema

PubMed Central

2012-01-01

Background Conventional transabdominal ultrasound usually fails to visualize parts of the ureter or extrahepatic bile duct covered by bowel gas. In this study, we propose a new method for gaining acoustic access to the ureters and extrahepatic bile duct to help determine the nature of obstruction to these structures when conventional transabdominal ultrasound fails. Methods The normal saline retention enema method, that is, using normal saline-filled colons to gain acoustic access to the bilateral ureters and extrahepatic bile duct and detecting the lesions with transabdominal ultrasonic diagnostic apparatus, was applied to 777 patients with obstructive lesions, including 603 with hydroureter and 174 with dilated common bile duct, which were not visualized by conventional ultrasonography. The follow-up data of all the patients were collected to verify the results obtained by this method. Results Of the 755 patients who successfully finished the examination after normal saline retention enema (the success rate of the enema is about 98%), the nature of obstruction in 718 patients was determined (the visualizing rate is approximately 95%), including 533 with ureteral calculus, 23 with ureteral stricture, 129 with extrahepatic bile duct calculus, and 33 with common bile duct tumor. Conclusions Colons filled fully with normal saline can surely give acoustic access to the bilateral ureters and extrahepatic bile duct so as to determine the nature of obstruction of these structures when conventional transabdominal ultrasound fails. PMID:22871226

fMRI-activation during drawing a naturalistic or sketchy portrait.

PubMed

Schaer, K; Jahn, G; Lotze, M

2012-07-15

Neural processes for naturalistic drawing might be discerned into object recognition and analysis, attention processes guiding eye hand interaction, encoding of visual features in an allocentric reference frame, a transfer into the motor command and precise motor guidance with tight sensorimotor feedback. Cerebral representations in a real life paradigm during naturalistic drawing have sparsely been investigated. Using a functional Magnetic Resonance Imaging (fMRI) paradigm we measured 20 naive subjects during drawing a portrait from a frontal face presented as a photograph. Participants were asked to draw the portrait in either a naturalistic or a sketchy characteristic way. Tracing the contours of the face with a pencil or passive viewing of the face served as control conditions. Compared to passive viewing, naturalistic and sketchy drawing recruited predominantly the dorsal visual pathway, somatosensory and motor areas and bilateral BA 44. The right occipital lobe, middle temporal (MT) and the fusiform face area were increasingly active during drawing compared to passive viewing as well. Compared to tracing with a pencil, both drawing tasks increasingly involved the bilateral precuneus together with the cuneus and right inferior temporal lobe. Overall, our study identified cerebral areas characteristic for previously proposed aspects of drawing: face perception and analysis (fusiform gyrus and higher visual areas), encoding and retrieval of locations in an allocentric reference frame (precuneus), and continuous feedback processes during motor output (parietal sulcus, cerebellar hemisphere). Copyright © 2012 Elsevier B.V. All rights reserved.

Atypical manifestation of progressive outer retinal necrosis in AIDS patient with CD4+ T-cell counts more than 100 cells/microL on highly active antiretroviral therapy.

PubMed

Vichitvejpaisal, Pornpattana; Reeponmahar, Somporn; Tantisiriwat, Woraphot

2009-06-01

Typical progressive outer retinal necrosis (PORN) is an acute ocular infectious disease in acquired immunodeficiency syndrome (AIDS) patients with extremely low CD4+ T-cell counts. It is a form of the Varicella- zoster virus (VZV) infection. This destructive infection has an extremely rapid course that may lead to blindness in affected eyes within days or weeks. Attempts at its treatment have had limited success. We describe the case of a bilateral PORN in an AIDS patient with an initial CD4+ T-cell count >100 cells/microL that developed after initiation of highly active antiretroviral therapy (HAART). A 29-year-old Thai female initially diagnosed with human immunodeficiency virus (HIV) in 1998, presented with bilaterally decreased visual acuity after initiating HAART two months earlier. Multiple yellowish spots appeared in the deep retina without evidence of intraocular inflammation or retinal vasculitis. Her CD4+ T-cell count was 127 cells/microL. She was diagnosed as having PORN based on clinical features and positive VZV in the aqueous humor and vitreous by polymerase chain reaction (PCR). Despite combined treatment with intravenous acyclovir and intravitreous ganciclovir, the patient's visual acuity worsened with no light-perception in either eye. This case suggests that PORN should be included in the differential diagnosis of reduced visual acuity in AIDS patients initiating HAART with higher CD4+ T-cell counts. PORN may be a manifestation of the immune reconstitution syndrome.

Neural networks for Braille reading by the blind.

PubMed

Sadato, N; Pascual-Leone, A; Grafman, J; Deiber, M P; Ibañez, V; Hallett, M

1998-07-01

To explore the neural networks used for Braille reading, we measured regional cerebral blood flow with PET during tactile tasks performed both by Braille readers blinded early in life and by sighted subjects. Eight proficient Braille readers were studied during Braille reading with both right and left index fingers. Eight-character, non-contracted Braille-letter strings were used, and subjects were asked to discriminate between words and non-words. To compare the behaviour of the brain of the blind and the sighted directly, non-Braille tactile tasks were performed by six different blind subjects and 10 sighted control subjects using the right index finger. The tasks included a non-discrimination task and three discrimination tasks (angle, width and character). Irrespective of reading finger (right or left), Braille reading by the blind activated the inferior parietal lobule, primary visual cortex, superior occipital gyri, fusiform gyri, ventral premotor area, superior parietal lobule, cerebellum and primary sensorimotor area bilaterally, also the right dorsal premotor cortex, right middle occipital gyrus and right prefrontal area. During non-Braille discrimination tasks, in blind subjects, the ventral occipital regions, including the primary visual cortex and fusiform gyri bilaterally were activated while the secondary somatosensory area was deactivated. The reverse pattern was found in sighted subjects where the secondary somatosensory area was activated while the ventral occipital regions were suppressed. These findings suggest that the tactile processing pathways usually linked in the secondary somatosensory area are rerouted in blind subjects to the ventral occipital cortical regions originally reserved for visual shape discrimination.

Development of tectal connectivity across metamorphosis in the bullfrog (Rana catesbeiana).

PubMed

Horowitz, Seth S; Simmons, Andrea Megela

2010-01-01

In the bullfrog (Rana catesbeiana), the process of metamorphosis culminates in the appearance of new visual and visuomotor behaviors reflective of the emergence of binocular vision and visually-guided prey capture behaviors as the animal transitions to life on land. Using several different neuroanatomical tracers, we examined the substrates that may underlie these behavioral changes by tracing the afferent and efferent connectivity of the midbrain optic tectum across metamorphic development. Intratectal, tectotoral, tectotegmental, tectobulbar, and tecto-thalamic tracts exhibit similar trajectories of neurobiotin fiber label across the developmental span from early larval tadpoles to adults. Developmental variability was apparent primarily in intensity and distribution of cell and puncta label in target nuclei. Combined injections of cholera toxin subunit β and Phaseolus vulgaris leucoagglutinin consistently label cell bodies, puncta, or fiber segments bilaterally in midbrain targets including the pretectal gray, laminar nucleus of the torus semicircularis, and the nucleus of the medial longitudinal fasciculus. Developmentally stable label was observed bilaterally in medullary targets including the medial vestibular nucleus, lateral vestibular nucleus, and reticular gray, and in forebrain targets including the posterior and ventromedial nuclei of the thalamus. The nucleus isthmi, cerebellum, lateral line nuclei, medial septum, ventral striatum, and medial pallium show more developmentally variable patterns of connectivity. Our results suggest that even during larval development, the optic tectum contains substrates for integration of visual with auditory, vestibular, and somatosensory cues, as well as for guidance of motivated behaviors. Copyright © 2011 S. Karger AG, Basel.

Decoding visual object categories in early somatosensory cortex.

PubMed

Smith, Fraser W; Goodale, Melvyn A

2015-04-01

Neurons, even in the earliest sensory areas of cortex, are subject to a great deal of contextual influence from both within and across modality connections. In the present work, we investigated whether the earliest regions of somatosensory cortex (S1 and S2) would contain content-specific information about visual object categories. We reasoned that this might be possible due to the associations formed through experience that link different sensory aspects of a given object. Participants were presented with visual images of different object categories in 2 fMRI experiments. Multivariate pattern analysis revealed reliable decoding of familiar visual object category in bilateral S1 (i.e., postcentral gyri) and right S2. We further show that this decoding is observed for familiar but not unfamiliar visual objects in S1. In addition, whole-brain searchlight decoding analyses revealed several areas in the parietal lobe that could mediate the observed context effects between vision and somatosensation. These results demonstrate that even the first cortical stages of somatosensory processing carry information about the category of visually presented familiar objects. © The Author 2013. Published by Oxford University Press.

Decoding Visual Object Categories in Early Somatosensory Cortex

PubMed Central

Smith, Fraser W.; Goodale, Melvyn A.

2015-01-01

Neurons, even in the earliest sensory areas of cortex, are subject to a great deal of contextual influence from both within and across modality connections. In the present work, we investigated whether the earliest regions of somatosensory cortex (S1 and S2) would contain content-specific information about visual object categories. We reasoned that this might be possible due to the associations formed through experience that link different sensory aspects of a given object. Participants were presented with visual images of different object categories in 2 fMRI experiments. Multivariate pattern analysis revealed reliable decoding of familiar visual object category in bilateral S1 (i.e., postcentral gyri) and right S2. We further show that this decoding is observed for familiar but not unfamiliar visual objects in S1. In addition, whole-brain searchlight decoding analyses revealed several areas in the parietal lobe that could mediate the observed context effects between vision and somatosensation. These results demonstrate that even the first cortical stages of somatosensory processing carry information about the category of visually presented familiar objects. PMID:24122136

Threat as a feature in visual semantic object memory.

PubMed

Calley, Clifford S; Motes, Michael A; Chiang, H-Sheng; Buhl, Virginia; Spence, Jeffrey S; Abdi, Hervé; Anand, Raksha; Maguire, Mandy; Estevez, Leonardo; Briggs, Richard; Freeman, Thomas; Kraut, Michael A; Hart, John

2013-08-01

Threatening stimuli have been found to modulate visual processes related to perception and attention. The present functional magnetic resonance imaging (fMRI) study investigated whether threat modulates visual object recognition of man-made and naturally occurring categories of stimuli. Compared with nonthreatening pictures, threatening pictures of real items elicited larger fMRI BOLD signal changes in medial visual cortices extending inferiorly into the temporo-occipital (TO) "what" pathways. This region elicited greater signal changes for threatening items compared to nonthreatening from both the natural-occurring and man-made stimulus supraordinate categories, demonstrating a featural component to these visual processing areas. Two additional loci of signal changes within more lateral inferior TO areas (bilateral BA18 and 19 as well as the right ventral temporal lobe) were detected for a category-feature interaction, with stronger responses to man-made (category) threatening (feature) stimuli than to natural threats. The findings are discussed in terms of visual recognition of processing efficiently or rapidly groups of items that confer an advantage for survival. Copyright © 2012 Wiley Periodicals, Inc.

Randomized Clinical Trial Comparing Low Density versus High Density Meshes in Patients with Bilateral Inguinal Hernia.

PubMed

Carro, Jose Luis Porrero; Riu, Sol Villar; Lojo, Beatriz Ramos; Latorre, Lucia; Garcia, Maria Teresa Alonso; Pardo, Benito Alcaide; Naranjo, Oscar Bonachia; Herrero, Alberto Marcos; Cabezudo, Carlos Sanchez; Herreras, Esther Quiros

2017-12-01

We present a randomized clinical trial to compare postoperative pain, complications, feeling of a foreign body, and recurrence between heavyweight and lightweight meshes in patients with bilateral groin hernia. Sixty-seven patients with bilateral hernia were included in our study. In each patient, the side of the lightweight mesh was decided by random numbers table. Pain score was measured by visual analogue scale, on 1st, 3rd, 5th, and 7th postoperative day, and one year after the surgery. There were no statistically significative differences between both meshes in postoperative complications. About differences of pain average, there were statistically significant differences only on the 1st postoperative day (P <0.01) and the 7th postoperative day (P <0.05). In the review after a year, there were no statistically significative differences in any parameter. In our study, we did not find statistically significative differences between lightweight and heavyweight meshes in postoperative pain, complications, feeling of a foreign body, and recurrence, except pain on 1st and 7th postoperative day.

Reversible postoperative blindness caused by bilateral status epilepticus amauroticus following thoracolumbar deformity correction: case report.

PubMed

Ibrahim, Tarik F; Sweis, Rochelle T; Nockels, Russ P

2017-07-01

Postoperative vision loss (POVL) is a devastating complication and has been reported after complex spine procedures. Anterior ischemic optic neuropathy and posterior optic neuropathy are the 2 most common causes of POVL. Bilateral occipital lobe seizures causing complete blindness are rare and have not been reported as a cause of POVL after spine surgery with the patient prone. The authors report the case of a 67-year-old man without a history of seizures who underwent a staged thoracolumbar deformity correction and developed POVL 6 hours after surgery. Imaging, laboratory, and ophthalmological examination results were nonrevealing. Routine electroencephalography study results were negative, but continuous electroencephalography captured bilateral occipital lobe seizures. The patient developed nonconvulsive status epilepticus despite initial treatment with benzodiazepines and loading doses of levetiracetam and lacosamide. He was therefore intubated for status epilepticus amauroticus and received a midazolam infusion. After electrographic seizure cessation for 48 hours, the patient was weaned off midazolam. The patient was maintained on levetiracetam and lacosamide without seizure recurrence and returned to his preoperative visual baseline status.

Visual cortex and cerebellum hyperactivation during negative emotion picture stimuli in migraine patients.

PubMed

Wang, Mengxing; Su, Jingjing; Zhang, Jilei; Zhao, Ying; Yao, Qian; Zhang, Qiting; Zhang, Hui; Wang, Shuo; Li, Ge-Fei; Liu, Jian-Ren; Du, Xiaoxia

2017-02-09

Migraines are a common and undertreated disease and often have psychiatric comorbidities; however, the abnormal mechanism of emotional processing in migraine patients has not been well clarified. This study sought to investigate the different brain functional activation to neutral, positive and negative emotional stimuli between migraine and healthy subjects. Twenty-six adults with migraines and 26 healthy adults, group-matched for sex and age, participated in this experiment. Although there were no significant differences between two groups during the viewing of positive affective pictures vs. neutral affective pictures, there were different activation patterns during the viewing of negative to neutral affective pictures in the two groups; the control group showed both increased and decreased activation patterns, while the migraine subjects showed only increased activation. Negative affective pictures elicited stronger activation than neutral affective pictures in migraineurs, which included the bilateral cerebellum anterior lobe/culmen, the bilateral lingual gyri, the bilateral precuneus and the left cuneus. Our data indicated that migraine patients were hypersensitive to negative stimuli, which might provide clues to aid in the understanding of the pathophysiology and psychiatric comorbidities of migraines.

Vestibular ablation and a semicircular canal prosthesis affect postural stability during head turns

PubMed Central

Thompson, Lara A.; Haburcakova, Csilla; Lewis, Richard F.

2016-01-01

In our study, we examined postural stability during head turns for two rhesus monkeys: one, single animal study contrasted normal and mild bilateral vestibular ablation and a second animal study contrasted severe bilateral vestibular ablation with and without prosthetic stimulation. The monkeys freely stood, unrestrained on a balance platform and made voluntary head turns between visual targets. To quantify each animals’ posture, motions of the head and trunk, as well as torque about the body’s center-of-mass, were measured. In the mildly ablated animal, we observed less foretrunk sway in comparison to the normal state. When the canal prosthesis provided electric stimulation to the severely ablated animal, it showed a decrease in trunk sway during head turns. Because the rhesus monkey with severe bilateral vestibular loss exhibited a decrease in trunk sway when receiving vestibular prosthetic stimulation, we propose that the prosthetic electrical stimulation partially restored head velocity information. Our results provide an indication that a semicircular canal prosthesis may be an effective way to improve postural stability in patients with severe peripheral vestibular dysfunction. PMID:27405997

Change in vision, visual disability, and health after cataract surgery.

PubMed

Helbostad, Jorunn L; Oedegaard, Maria; Lamb, Sarah E; Delbaere, Kim; Lord, Stephen R; Sletvold, Olav

2013-04-01

Cataract surgery improves vision and visual functioning; the effect on general health is not established. We investigated if vision, visual functioning, and general health follow the same trajectory of change the year after cataract surgery and if changes in vision explain changes in visual disability and general health. One-hundred forty-eight persons, with a mean (SD) age of 78.9 (5.0) years (70% bilateral surgery), were assessed before and 6 weeks and 12 months after surgery. Visual disability and general health were assessed by the CatQuest-9SF and the Short Formular-36. Corrected binocular visual acuity, visual field, stereo acuity, and contrast vision improved (P < 0.001) from before to 6 weeks after surgery, with further improvements of visual acuity evident up to 12 months (P = 0.034). Cataract surgery had an effect on visual disability 1 year later (P < 0.001). Physical and mental health improved after surgery (P < 0.01) but had returned to presurgery level after 12 months. Vision changes did not explain visual disability and general health 6 weeks after surgery. Vision improved and visual disability decreased in the year after surgery, whereas changes in general health and visual functioning were short-term effects. Lack of associations between changes in vision and self-reported disability and general health suggests that the degree of vision changes and self-reported health do not have a linear relationship.

Multifocal Choroiditis with Retinal Vasculitis, Optic Neuropathy, and Keratoconus in a Young Saudi Male.

PubMed

Dhafiri, Yousef; Al Rubaie, Khalid; Kirat, Omar; May, William N; Nguyen, Quan D; Kozak, Igor

2017-01-01

The purpose of this study is to describe an association of unilateral multifocal choroiditis (MFC), retinal vasculitis, optic neuropathy, and bilateral keratoconus in a young Saudi male. A 27-year-old male patient with stable bilateral keratoconus presented with a painless vision loss in his left eye. Ophthalmic examinations revealed multiple foci of idiopathic chorioretinitis, retinal vasculitis, and mild optic disc leakage on fluorescein angiography, all of which resolved on systemic therapy with mycophenolate mofetil and prednisone after 3 months. Systemic medication was stopped after 8 months. One year after presentation, patient's visual acuity has improved and remained stable. Systemic immunomodulatory therapy can be effective in managing and leading to resolution of MFC, retinal vasculitis, and optic disc leak in young patients.

Meridional lenticular astigmatism associated with bilateral concurrent uveal metastases in renal cell carcinoma

PubMed Central

Priluck, Joshua C; Grover, Sandeep; Chalam, KV

2012-01-01

Purpose To demonstrate a case illustrating meridional lenticular astigmatism as a result of renal cell carcinoma uveal metastases. Methods Case report with images. Results Clinical findings and diagnostic testing of a patient with acquired meridional lenticular astigmatism are described. The refraction revealed best-corrected visual acuity of 20/20–1 OD (−2.50 + 0.25 × 090) and 20/50 OS (−8.25 + 3.25 × 075). Bilateral concurrent renal cell carcinoma metastases to the choroid and ciliary body are demonstrated by utilizing ultrasonography, ultrawidefield fluorescein angiography, and unique spectral-domain optical coherence tomography. Conclusions Metastatic disease should be included in the differential of acquired astigmatism. Spectral-domain optical coherence tomography, ultrawidefield fluorescein angiography, and ultrasonography have roles in delineating choroidal metastases. PMID:23152663

Accommodative spasm with bilateral vision loss due to untreated intermittent exotropia in an adult.

PubMed

Shanker, V; Ganesh, S; Sethi, S

2012-01-01

Intermittent exotropia (IXT) is an exodeviation intermittently controlled by fusional mechanisms. Patients with IXT may present with asthenopic symptoms, blurred vision, headaches, diplopia or visual confusion and reading difficulties; especially after prolonged periods of near work. To report the presentation and management of a young adult with intractable accommodative spasm secondary to long standing intermittent exotropia. The patient was found to have bilateral accommodative spasm with high pseudomyopia and severe impairment of vision. There was a tendency for recurrence with discontinuation of cycloplegics. A total relief of symptoms was noticed after strabismus surgery was undertaken for the exotropia. A detailed orthoptic evaluation with emphasis on recognizing accommodative spasm as an unusual presentation of IXT, could aid in appropriate diagnosis and treatment of such cases. © NEPjOPH.

Implicit representations of space after bilateral parietal lobe damage.

PubMed

Kim, M S; Robertson, L C

2001-11-15

There is substantial evidence that the primate cortex is grossly divided into two functional streams, an occipital-parietal-frontal pathway that processes "where" and an occipital-temporal-frontal pathway that processes "what" (Ungerleider and Mishkin, 1982). In humans, bilateral occipital-parietal damage results in severe spatial deficits and a neuropsychological disorder known as Balint's syndrome in which a single object can be perceived (simultanagnosia) but its location is unknown (Balint, 1995). The data reported here demonstrate that spatial information for visual features that cannot be explicitly located is represented normally below the level of spatial awareness even with large occipital-parietal lesions. They also demonstrate that parietal damage does not affect preattentive spatial coding of feature locations or complex spatial relationships between parts of a stimulus despite explicit spatial deficits and simultanagnosia.

A case of complete double aortic arch visualized by transthoracic echocardiography.

PubMed

Saito, Naka; Kato, Shingo; Saito, Noritaka; Nakachi, Tatsuya; Fukui, Kazuki; Iwasawa, Tae; Kosuge, Masami; Kimura, Kazuo

2017-08-01

A case of double aortic arch that was well visualized using transthoracic echocardiography is reported. A 38-year-old man underwent transthoracic echocardiography for the evaluation of dyspnea. A suprasternal view of transthoracic echocardiography showed the ascending aorta bifurcate to left and right aortic arches, with blood flow from the ascending aorta to bilateral aortic arches. The diagnosis of right side-dominant double aortic arch was made, and the patient's symptom was conceivably related to compression of the trachea due to a vascular ring. This report indicates the potential usefulness of transthoracic echocardiography for noninvasive detection of double aortic arch in adults. © 2017, Wiley Periodicals, Inc.

Ocular chemical injuries and their management.

PubMed

Singh, Parul; Tyagi, Manoj; Kumar, Yogesh; Gupta, K K; Sharma, P D

2013-05-01

Chemical burns represent potentially blinding ocular injuries and constitute a true ocular emergency requiring immediate assessment and initiation of treatment. The majority of victims are young and exposure occurs at home, work place and in association with criminal assaults. Alkali injuries occur more frequently than acid injuries. Chemical injuries of the eye produce extensive damage to the ocular surface epithelium, cornea, anterior segment and limbal stem cells resulting in permanent unilateral or bilateral visual impairment. Emergency management if appropriate may be single most important factor in determining visual outcome. This article reviews the emergency management and newer techniques to improve the prognosis of patients with chemical injuries.

Penetrating keratoplasty in infancy and early childhood.

PubMed

Reidy, J J

2001-08-01

Penetrating keratoplasty in infants and young children is performed on an infrequent basis. The most common indication is visually significant congenital corneal opacity. Surgery must be performed early to avoid amblyopia. Surgical techniques differ from those used in adult penetrating keratoplasty because of the reduced ocular rigidity encountered in infants and young children. Use of a multispecialty team approach is important to improve visual outcome. Poor prognostic indicators include bilateral disease, concomitant infantile glaucoma, lensectomy and vitrectomy at the time of surgery, previous graft failure, extensive goniosynechiae, and extensive corneal vascularization. Prompt postoperative optical rehabilitation, combined with occlusion therapy when appropriate, is an important determinant of success.

Enantiomorphism and rule similarity in the astigmatism axes of fellow eyes: A population-based study.

PubMed

Hashemi, Hassan; Asharlous, Amir; Yekta, Abbasali; Ostadimoghaddam, Hadi; Mohebi, Masumeh; Aghamirsalim, Mohamadreza; Khabazkhoob, Mehdi

2018-04-03

To evaluate the relationship patterns between astigmatism axes of fellow eyes (rule similarity and symmetry) and to determine the prevalence of each pattern in the studied population. This population-based study was conducted in 2015 in Iran. All participants had tests for visual acuity, objective refraction, subjective refraction (if cooperative), and assessment of eye health at the slit-lamp. Axis symmetry was based on two different patterns: direct (equal axes) and mirror (mirror image symmetry) or enantiomorphism. Bilateral astigmatism was classified as isorule if fellow eyes had the same orientation (e.g. both eyes were with-the-rule) and as anisorule if otherwise. Of the total cases of bilateral astigmatism, 80% were isorule, and in the studied population, the prevalence of isorule and anisorule astigmatism was 14.89% and 3.53%, respectively. The prevalence of isorule increased with age (p<0.001). The prevalence of both isorule and anisorule increased at higher degrees of spherical ametropia (p<0.001). Median inter-ocular axis difference was 10° in mirror symmetry and 20° in direct symmetry with no significant difference between two genders (p>0.288). Both symmetry patterns reduced with age (p<0.001). Among cases of bilateral astigmatism, 15.5% and 19.8% had exact direct and mirror symmetry, respectively. Bilateral astigmatism is mainly isorule in the population and anisorule astigmatism is rare. The enantiomorphism is the most common pattern in the population of bilateral astigmatism. Copyright © 2018 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

Distance vision after bilateral implantation of AcrySof toric intraocular lenses: a randomized, controlled, prospective trial

PubMed Central

Zhang, Jin-Song; Zhao, Jiang-Yue; Sun, Qi; Ma, Li-Wei

2011-01-01

AIM To evaluate the distance vision of Chinese patients with cataracts and corneal astigmatism after implantation of bilateral AcrySof toric intraocular lens (IOL) versus bilateral AcrySof spherical IOL. METHODS This study randomized 60 patients into equal groups to receive toric IOL or spherical IOL. IOL powers targeting emmetropia were selected for 93% of toric IOL patients and for 90% of spherical IOL patients. Assessments included monocular and binocular distance vision, with and without best correction. Patients also completed surveys about their distance vision. RESULTS Preoperatively, the two study groups were similar in age, in distance visual acuity, and in the magnitude of corneal astigmatism. At 6 months postoperative, binocular uncorrected distance vision was 0.06±0.14 logMAR in the AcrySof toric IOL group, significantly better than the 0.14±0.11 logMAR in the spherical IOL group (P<0.05). For eyes with emmetropia as a target, the equivalent of 20/20 uncorrected vision was more likely (P<0.001) in the toric IOL group (36% of eyes) than in the spherical IOL group (4% of eyes). No patients in the emmetropia/toric IOL group used distance glasses, as compared to 52% of patients in the emmetropia/spherical IOL group. All patients were satisfied or highly satisfied. Quality of distance vision was rated higher by toric IOL patients than by spherical IOL patients (P<0.05). CONCLUSION Bilateral AcrySof toric IOL is superior to bilateral spherical IOL in providing uncorrected distance vision to cataract patients with corneal astigmatism. PMID:22553636

Large-Scale Functional Brain Network Reorganization During Taoist Meditation.

PubMed

Jao, Tun; Li, Chia-Wei; Vértes, Petra E; Wu, Changwei Wesley; Achard, Sophie; Hsieh, Chao-Hsien; Liou, Chien-Hui; Chen, Jyh-Horng; Bullmore, Edward T

2016-02-01

Meditation induces a distinct and reversible mental state that provides insights into brain correlates of consciousness. We explored brain network changes related to meditation by graph theoretical analysis of resting-state functional magnetic resonance imaging data. Eighteen Taoist meditators with varying levels of expertise were scanned using a within-subjects counterbalanced design during resting and meditation states. State-related differences in network topology were measured globally and at the level of individual nodes and edges. Although measures of global network topology, such as small-worldness, were unchanged, meditation was characterized by an extensive and expertise-dependent reorganization of the hubs (highly connected nodes) and edges (functional connections). Areas of sensory cortex, especially the bilateral primary visual and auditory cortices, and the bilateral temporopolar areas, which had the highest degree (or connectivity) during the resting state, showed the biggest decrease during meditation. Conversely, bilateral thalamus and components of the default mode network, mainly the bilateral precuneus and posterior cingulate cortex, had low degree in the resting state but increased degree during meditation. Additionally, these changes in nodal degree were accompanied by reorganization of anatomical orientation of the edges. During meditation, long-distance longitudinal (antero-posterior) edges increased proportionally, whereas orthogonal long-distance transverse (right-left) edges connecting bilaterally homologous cortices decreased. Our findings suggest that transient changes in consciousness associated with meditation introduce convergent changes in the topological and spatial properties of brain functional networks, and the anatomical pattern of integration might be as important as the global level of integration when considering the network basis for human consciousness.

Normal postural responses preceding shoulder flexion: co-activation or asymmetric activation of transverse abdominis?

PubMed

Davarian, Sanaz; Maroufi, Nader; Ebrahimi, Esmaeil; Parnianpour, Mohammad; Farahmand, Farzam

2014-01-01

It is suggested that activation of the transverse abdominis muscle has a stabilizing effect on the lumbar spine by raising intra-abdominal pressure without added disc compression. However, its feedforward activity has remained a controversial issue. In addition, research regarding bilateral activation of trunk muscles during a unilateral arm movement is limited. The aim of this study was to evaluate bilateral anticipatory activity of trunk muscles during unilateral arm flexion. Eighteen healthy subjects (aged 25 ± 3.96 years) participated in this study and performed 10 trials of rapid arm flexion in response to a visual stimulus. The electromyographic activity of the right anterior deltoid (AD) and bilateral trunk muscles including the transverse abdominis/internal oblique (TA/IO), superficial lumbar multifidus (SLM) and lumbar erector spine (LES) was recorded. The onset latency and anticipatory activity of the recorded trunk muscles were calculated. The first muscle activated in anticipation of the right arm flexion was the left TA/IO. The right TA/IO activated significantly later than all other trunk muscles (P < 0.0005). In addition, anticipatory activity of the right TA/IO was significantly lower than all other trunk muscles (P < 0.0005). There was no significant difference in either onset latency or anticipatory activity among other trunk muscles (P > 0.05). Healthy subjects showed no bilateral anticipatory co-activation of TA/IO in unilateral arm elevation. Further investigations are required to delineate normal muscle activation pattern in healthy subjects prior to prescribing bilateral activation training of transverse abdominis for subjects with chronic low back pain.

The effects of lesions of the superior colliculus on locomotor orientation and the orienting reflex in the rat.

PubMed

Goodale, M A; Murison, R C

1975-05-02

The effects of bilateral removal of the superior colliculus or visual cortex on visually guided locomotor movements in rats performing a brightness discrimination task were investigated directly with the use of cine film. Rats with collicular lesions showed patterns of locomotion comparable to or more efficient than those of normal animals when approaching one of 5 small doors located at one end of a large open area. In contrast, animals with large but incomplete lesions of visual cortex were distinctly impaired in their visual control of approach responses to the same stimuli. On the other hand, rats with collicular damage showed no orienting reflex or evidence of distraction in the same task when novel visual or auditory stimuli were presented. However, both normal and visual-decorticate rats showed various components of the orienting reflex and disturbance in task performance when the same novel stimuli were presented. These results suggest that although the superior colliculus does not appear to be essential to the visual control of locomotor orientation, this midbrain structure might participate in the mediation of shifts in visual fixation and attention. Visual cortex, while contributing to visuospatial guidance of locomotor movements, might not play a significant role in the control and integration of the orienting reflex.

Cytomegalovirus retinitis and HIV: Case reviews from KwaZulu-Natal Province, South Africa.

PubMed

Hassan-Moosa, R; Chinappa, T; Jeena, L; Visser, L; Naidoo, K

2017-09-22

Retinal cytomegalovirus (CMV) infection is a common opportunistic infection and remains a significant contributor to visual loss in patients with AIDS. We highlight the poor outcomes of CMV retinitis in three HIV-infected patients who were initiated on antiretroviral therapy (ART). We conducted a retrospective chart review of advanced stage HIV-infected patients with known CMV retinitis.Case 1. A 37-year-old man, with a CD4+ cell count of 35 cells/µL, presented for ART initiation with a 5-month history of visual loss in his left eye. Fundoscopy showed left eye CMV retinitis and right eye HIV retinopathy. ART and 5 months of weekly intravitreal ganciclovir injections (left eye) were commenced. Six-month outcomes included virological suppression, and visual acuity in the right eye of 6/6 and in the left eye of 3/60.Case 2. A 31-year-old woman, with a CD4+ cell count of 39 cells/µL and on tuberculosis therapy, presented for ART initiation. She presented with a 2-month history of decreased visual acuity. Fundoscopy showed bilateral CMV retinitis, which was more pronounced in the left eye. ART and 8 months of intravitreal ganciclovir injections were commenced. Six-month outcomes included virological suppression and visual acuity in the right eye of 6/9, and in the left eye of 6/24.Case 3. A 29-year-old woman, with a CD4+ cell count of 24 cells/µL, who was on tuberculosis therapy and ART, complained of blurred vision at her 2-month ART follow-up visit. Fundoscopy showed bilateral retinal detachment secondary to CMV retinitis. While silicone oil tamponade and subsequent retinectomy successfully repaired the right eye, extensive damage rendered the left eye irreparable. Six-month outcomes included virological suppression, with 6/120 visual acuity in the right eye and complete blindness in the left eye. CMV retinitis causes debilitating, permanent sequelae, which is preventable by ART initiation at higher CD4+ cell counts. Despite achieving virological suppression, vision could not be completely restored in these patients, irrespective of the severity of CMV retinitis.

Memory-guided saccade processing in visual form agnosia (patient DF).

PubMed

Rossit, Stéphanie; Szymanek, Larissa; Butler, Stephen H; Harvey, Monika

2010-01-01

According to Milner and Goodale's model (The visual brain in action, Oxford University Press, Oxford, 2006) areas in the ventral visual stream mediate visual perception and oV-line actions, whilst regions in the dorsal visual stream mediate the on-line visual control of action. Strong evidence for this model comes from a patient (DF), who suffers from visual form agnosia after bilateral damage to the ventro-lateral occipital region, sparing V1. It has been reported that she is normal in immediate reaching and grasping, yet severely impaired when asked to perform delayed actions. Here we investigated whether this dissociation would extend to saccade execution. Neurophysiological studies and TMS work in humans have shown that the posterior parietal cortex (PPC), on the right in particular (supposedly spared in DF), is involved in the control of memory-guided saccades. Surprisingly though, we found that, just as reported for reaching and grasping, DF's saccadic accuracy was much reduced in the memory compared to the stimulus-guided condition. These data support the idea of a tight coupling of eye and hand movements and further suggest that dorsal stream structures may not be sufficient to drive memory-guided saccadic performance.

On-road Driving Performance of Patients with Bilateral Moderate and Advanced Glaucoma

PubMed Central

Bhorade, Anjali M.; Yom, Victoria H.; Barco, Peggy; Wilson, Bradley; Gordon, Mae; Carr, David

2017-01-01

Purpose To compare on-road driving performance of patients with moderate or advanced glaucoma to controls and evaluate factors associated with unsafe driving. Design Case-control pilot study. Methods A consecutive sample of 21 patients with bilateral moderate or advanced glaucoma from Washington University, St. Louis, MO and 38 community-dwelling controls were enrolled. Participants, ages 55–90 years, underwent a comprehensive clinical evaluation by a trained occupational therapist and an on-road driving evaluation by a masked driver rehabilitation specialist. Overall driving performance of pass vs. marginal/fail and number of wheel and/or brake interventions were recorded. Results Fifty-two percent of glaucoma participants scored a marginal/fail compared to 21% of controls (odds ratio [OR], 4.1; 95% CI, 1.30–13.14;p=.02). Glaucoma participants had a higher risk of wheel interventions than controls (OR, 4.67; 95% CI, 1.03–21.17;p=.046). There were no differences detected between glaucoma participants who scored a pass vs. marginal/fail for visual field mean deviation of the better (p=.62) or worse (p=.88) eye, binocular distance (p=.15) or near (p=.23) visual acuity, contrast sensitivity (p=.28) or glare (p=.88). However, glaucoma participants with a marginal/fail score performed worse on Trail Making Tests A (p=.03) and B (p=.05), right-sided Jamar grip strength (p=.02), Rapid Pace Walk (p=.03), Braking Response Time (p=.03), and identifying traffic signs (p=.05). Conclusions and Relevance Patients with bilateral moderate or advanced glaucoma are at risk for unsafe driving – particularly those with impairments on psychometric and mobility tests. A comprehensive clinical assessment and on-road driving evaluation is recommended to effectively evaluate driving safety of these patients. PMID:26949136

Association of bilateral oophorectomy with cognitive function in healthy, postmenopausal women.

PubMed

Kurita, Keiko; Henderson, Victor W; Gatz, Margaret; St John, Jan; Hodis, Howard N; Karim, Roksana; Mack, Wendy J

2016-09-01

To investigate the association between bilateral oophorectomy and cognitive performance in healthy, older women. Retrospective analysis of clinical trial data. Academic research institution. Healthy postmenopausal women without signs or symptoms of cardiovascular disease or diabetes (n = 926). Randomized interventions (not the focus of this analysis) in analyzed trials included B-vitamins, soy isoflavones, oral estradiol, and matching placebos. Measures in five cognitive domains (executive functions, semantic memory, logical memory, visual memory, and verbal learning) and global cognitive function. Using data from three clinical trials conducted under uniform conditions, bilateral oophorectomy and its timing were analyzed cross-sectionally and longitudinally in relation to cognitive function in linear regression models. Covariates included age, education, race/ethnicity, body mass index, trial, and randomized treatment (in longitudinal models). Duration of menopausal hormone use was considered as a possible mediator and effect modifier. Median age of oophorectomy was 45 years. When evaluating baseline cognition, we found that surgical menopause after 45 years of age was associated with lower performance in verbal learning compared with natural menopause. Evaluating the change in cognition over approximately 2.7 years, surgical menopause was associated with performance declines in visual memory for those who had an oophorectomy after 45 years of age and in semantic memory for those who had oophorectomy before 45 years of age compared with natural menopause. Oophorectomy after natural menopause was not associated with cognitive performance. Adjustment for duration of hormone use did not alter these associations. Cognitive associations with ovarian removal vary by timing of surgery relative to both menopause and age. Copyright © 2016. Published by Elsevier Inc.

Outcomes and projected impact on vision restoration of the China Million Cataract Surgeries Program.

PubMed

Yan, Xixi; Guan, Chunhong; Mueller, Andreas; Iezzi, Beatrice; He, Mingguang; Liang, Hui; Meltzer, Mirjam; Congdon, Nathan G

2013-10-01

The recently completed Chinese "Million Cataract Surgeries Program" (MCSP) is among the largest such campaigns ever, providing 1.05 million operations. We report MCSP outcomes for the first time, in Jiangxi, the province with the greatest program output. Ten county hospitals participating in MCSP were selected in Jiangxi (range of gross domestic product per capita US$743-2998). Each hospital sought to enroll 75 consecutive MCSP patients aged ≥ 50 years. Data recorded included type of cataract procedure, bilateral uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), and refractive error pre- and ≥ 50 days postoperatively. Among 715 patients (mean age 72.3 ± 9.1 years, 55.5% female), preoperative UCVA was <3/60 (legally blind) bilaterally in 13.3% and unilaterally in the operated eye in 50.9%. No subjects had UCVA >6/18 preoperatively. Small incision cataract surgery was performed in 92.3% patients. Among 662 patients (92.6%) completing follow-up was ≥ 40 days after surgery, BCVA was ≥ 6/18 in 80.1%, UCVA was ≥ 6/18 in 57.1% and UCVA was <3/60 in 2.1%. Older age (p < 0.001), female sex (p = 0.04), worse refractive error (p = 0.02) and presence of intra- (p = 0.002) and postoperative surgical complications (p < 0.001), were independently associated with worse postoperative UCVA. Based on these results, the MCSP cured an estimated 124,950 cases (13.3% × [100-2.1%] × 1.05 million) of bilateral and 502,500 (50.9% × [100-2.1%] × 1.05 million) of unilateral blindness. Due to relatively good outcomes and the large number of surgeries performed on blind persons, the sight-restoring impact of the MCSP was probably substantial.

AN ELDERLY PATIENT WITH ACUTE TRANSIENT OUTER RETINAL DISRUPTION RESEMBLING BILATERAL MULTIPLE EVANESCENT WHITE DOT SYNDROME.

PubMed

Golshani, Cyrus; Gal-Or, Orly; Giovinazzo, Vincent; Freund, K Bailey

2017-11-07

To report an unusual case of an elderly patient with transient outer retinal disruption resembling bilateral multiple evanescent white dot syndrome. Observational case report. Fundus photographs, fluorescein angiography, standard and ultra-widefield fundus autofluorescence, and cross-sectional and en face optical coherence tomography were used to characterize and describe the clinical findings. A 67-year-old woman presented with decreased vision and floaters in her left eye. Best-corrected visual acuity was 20/20-3 in the right eye and 20/80-2 in the left eye. Funduscopic examination showed small deep white dots and foveal granularity of the left eye corresponding to hyperautofluorescent spots on fundus autofluorescence and ellipsoid zone disruption on spectral domain optical coherence tomography. The asymptomatic right eye had evidence of subretinal deposits on spectral domain optical coherence tomography but was otherwise unremarkable. At 4-week follow-up, the patient noted resolution of her symptoms in the left eye but had developed floaters and blurry vision in her right eye. The left eye showed resolving white spots and ellipsoid zone disruption. However, the right eye had new evidence of white spots corresponding to hyperautofluorescent spots on fundus autofluorescence. Spectral domain optical coherence tomography demonstrated subretinal deposits overlying areas of ellipsoid zone disruption. At 8-week follow-up, the patient was asymptomatic in both eyes with best-corrected visual acuity of 20/20 in both eyes. The hyperautofluorescent spots on ultra-widefield fundus autofluorescence had faded with restoration of ellipsoid zone disruption in both eyes and disappearance of subretinal deposits. Our case demonstrates multimodal retinal imaging findings resembling multiple evanescent white dot syndrome in an elderly patient. The bilateral presentation, presence of subretinal deposits before symptom onset, and older age of the patient were atypical features for this entity.

Effects of 30-Day Head-Down Bed Rest on Ocular Structures and Visual Function in a Healthy Subject

PubMed Central

Taibbi, Giovanni; Kaplowitz, Kevin; Cromwell, Ronita L.; Godley, Bernard F.; Zanello, Susana B.; Vizzeri, Gianmarco

2013-01-01

Introduction We report ocular changes occurring in a healthy human subject enrolled in a bed rest (BR) study designed to replicate the effects of a low-gravity environment. Case report A 25-year-old Caucasian male spent 30 consecutive days in a 6° head-down-tilt position at the NASA Flight Analogs Research Unit. Comprehensive ophthalmologic exams, optic disc stereo-photography, Standard Automated Perimetry (SAP) and optic disc Spectralis OCT scans were performed at baseline, immediately post-BR (BR+0) and 6 months post-BR. Main outcome measures: changes in best-corrected visual acuity, intraocular pressure (IOP), cycloplegic refraction, SAP and Spectralis OCT measures. At BR+0 IOP was 11 and 10 mmHg in the right (OD) and left eye (OS), respectively (a bilateral 4 mmHg decrease compared to baseline); SAP documented a possible bilateral symmetrical inferior scotoma; Spectralis OCT showed an average 19.4 μm (+5.2%) increase in peripapillary retinal thickness, and an average 0.03 mm3 (+5.0%) increase in peripapillary retinal volume bilaterally. However, there were no clinically detectable signs of optic disc edema. 6 months post-BR, IOP was 13 and 14 mmHg in OD and OS, respectively, and the scotoma had resolved. Spectralis OCT measurements matched the ones recorded at baseline. Discussion In this subject, a reduction in IOP associated with subtle structural and functional changes compared to baseline were documented after prolonged head-down BR. These changes may be related to cephalad fluid shifts in response to tilt. Further studies should clarify whether decreased translaminar pressure (i.e., the difference between IOP and intracranial pressure) may be responsible for these findings. PMID:23447853

Genotype-phenotype variability of retinal manifestation in primary hyperoxaluria type 1.

PubMed

Dulz, S; Bigdon, E; Atiskova, Y; Schuettauf, F; Cerkauskiene, R; Oh, J; Brinkert, F

2018-04-01

Primary hyperoxaluria type 1 (PH1) is a rare congenital metabolic disorder of the glyoxylate pathway, which manifests with nephrocalcinosis, urolithiasis, and end-stage renal failure (ESRD) as well as deposition of oxalate crystals within ocular tissues. This report demonstrates classical ocular features of PH1 of the posterior pole and furthermore highlights the ocular genotype-phenotype variability among siblings with identical compound heterozygous alanine-glyoxylate aminotransferase (AGXT) mutations. Two siblings, an 8-year-old boy and an 18-year-old girl, with genetically confirmed AGXT mutation (c.364C>T (p.R122X) and c.33dupC), but different renal phenotype underwent an ophthalmic examination, including slit-lamp examination and funduscopy as well as optical coherence tomography (OCT), near-infrared autofluorescence (NIA), and microperimetry examination. The 8-year-old boy presented with a best-corrected visual acuity (BCVA) of 20/630. Fundus examination revealed bilateral, whitish oxalate deposits and prominent fibrotic macular scars. OCT imaging illustrated hyperdense deposits in all retinal layers and the choroid and the vitreous body along with a prominent dome-shaped macular fibrosis. NIA imaging outlined macular retinal pigment epithelium (RPE) atrophy with panretinal hyperreflective material. Bilateral symptomatic epiphora was putatively due to bilateral depositions of palpable nodular oxalate deposits at the level of the lacrimal sac. In contrary, the 18-year-old sister presented without any signs of ocular oxalate deposition and a BCVA of 20/20. PH1 is potentially accompanied with a considerable decline in visual acuity due to macular scaring and fibrosis, whereas a profound variability of ocular manifestations can be observed in PH1 patients with identical genotypes.

The Mechanisms Underlying the Interhemispheric Integration of Information in Foveal Word Recognition: Evidence for Transcortical Inhibition

ERIC Educational Resources Information Center

Van der Haegen, Lise; Brysbaert, Marc

2011-01-01

Words are processed as units. This is not as evident as it seems, given the division of the human cerebral cortex in two hemispheres and the partial decussation of the optic tract. In two experiments, we investigated what underlies the unity of foveally presented words: A bilateral projection of visual input in foveal vision, or interhemispheric…

Presumed atypical HDR syndrome associated with Band Keratopathy and pigmentary retinopathy.

PubMed

Kim, Cinoo; Cheong, Hae Il; Kim, Jeong Hun; Yu, Young Suk; Kwon, Ji Won

2011-01-01

This report describes presumed atypical hypoparathyroidism, deafness, and renal dysplasia (HDR) syndrome associated with unexpected ocular findings. The patient had exotropia, bilateral band keratopathy, and pigmentary retinopathy, including attenuated retinal vessels and atrophy of the retinal pigment epithelium. Even though the calcific plaques were successfully removed, visual acuity in both eyes gradually decreased and electroretinography was extinguished. Copyright 2009, SLACK Incorporated.

Cadaveric feasibility study of da Vinci Si-assisted cochlear implant with augmented visual navigation for otologic surgery.

PubMed

Liu, Wen P; Azizian, Mahdi; Sorger, Jonathan; Taylor, Russell H; Reilly, Brian K; Cleary, Kevin; Preciado, Diego

2014-03-01

To our knowledge, this is the first reported cadaveric feasibility study of a master-slave-assisted cochlear implant procedure in the otolaryngology-head and neck surgery field using the da Vinci Si system (da Vinci Surgical System; Intuitive Surgical, Inc). We describe the surgical workflow adaptations using a minimally invasive system and image guidance integrating intraoperative cone beam computed tomography through augmented reality. To test the feasibility of da Vinci Si-assisted cochlear implant surgery with augmented reality, with visualization of critical structures and facilitation with precise cochleostomy for electrode insertion. Cadaveric case study of bilateral cochlear implant approaches conducted at Intuitive Surgical Inc, Sunnyvale, California. Bilateral cadaveric mastoidectomies, posterior tympanostomies, and cochleostomies were performed using the da Vinci Si system on a single adult human donor cadaveric specimen. Radiographic confirmation of successful cochleostomies, placement of a phantom cochlear implant wire, and visual confirmation of critical anatomic structures (facial nerve, cochlea, and round window) in augmented stereoendoscopy. With a surgical mean time of 160 minutes per side, complete bilateral cochlear implant procedures were successfully performed with no violation of critical structures, notably the facial nerve, chorda tympani, sigmoid sinus, dura, or ossicles. Augmented reality image overlay of the facial nerve, round window position, and basal turn of the cochlea was precise. Postoperative cone beam computed tomography scans confirmed successful placement of the phantom implant electrode array into the basal turn of the cochlea. To our knowledge, this is the first study in the otolaryngology-head and neck surgery literature examining the use of master-slave-assisted cochleostomy with augmented reality for cochlear implants using the da Vinci Si system. The described system for cochleostomy has the potential to improve the surgeon's confidence, as well as surgical safety, efficiency, and precision by filtering tremor. The integration of augmented reality may be valuable for surgeons dealing with complex cases of congenital anatomic abnormality, for revision cochlear implant with distorted anatomy and poorly pneumatized mastoids, and as a method of interactive teaching. Further research into the cost-benefit ratio of da Vinci Si-assisted otologic surgery, as well as refinements of the proposed workflow, are required before considering clinical studies.

[Clinical findings in members of a Czech family with retinitis pigmentosa caused by the c.2426_2427delAG mutation in RPGR].

PubMed

Kousal, B; Skalická, P; Diblík, P; Kuthan, P; Langrová, H; Lišková, P

2013-03-01

To describe the phenotype of members of the first Czech retinitis pigmentosa family with an identified molecular genetic cause (c.2426_2427delAG in RPGR), followed for more than 13 years. Medical records were reviewed and a detailed ophthalmic examination including spectral-domain optical coherence tomography and full-field and multifocal electroretinography (ERG) was performed in two affected males, three female carriers and one unaffected female. A 22-year-old male who denied suffering from nyctalopia had a best corrected visual acuity (BCVA) of 0.63 in both eyes. Moderate myopia and myopic astigmatism were present bilaterally. Color vision and contrast sensitivity were normal. There was an eccentric constriction of the visual fields that spared the central 20 degrees in both eyes. Fundus examination revealed bilateral pigmentary changes in the mid-periphery. Full-field ERG documented a 10% rod and 20% cone response. The phenotype of his cousin, also aged 22 years, was more severe. He complained of nyctalopia since 12 years of age. His BCVA was 0.3 in the right eye and 0.5 in the left eye. Myopia and astigmatism were present bilaterally. Contrast sensitivity and color vision were severely impaired. Full field ERG was extinct, but some activity on multifocal ERG was still detectable. The constriction of the visual fields reached 5 degrees in both eyes. Fundus examination showed the typical retinitis pigmentosa appearance. All carriers denied that they suffered from nyctalopia, but two of them had decreased BCVA in at least one eye. None exhibited typical bone spicules or a tapetal-like reflex. Significant refractive errors were present in all eyes of the carriers. The finding of moderate or high myopia and astigmatism in males with retinitis pigmentosa as well as refractive errors in female relatives indicates possible X-linked inheritance, which may be especially important in pedigrees where the transmission pattern can not be clearly established. Our study highlights the inter-individual variability in phenotype observed in similar aged patients with identical ORF15 RPGR mutations.

Measuring aniseikonia using scattering filters to simulate cataract

NASA Astrophysics Data System (ADS)

Wilson, Jason

2011-12-01

The relationship between anisometropia and aniseikonia (ANK) is not well understood. Ametropic cataract patients provide a unique opportunity to study this relationship after undergoing emmetropizing lens extraction. Because light scatter may affect ANK measurement in cataract patients, its effect should also be evaluated. The Basic Aniseikonia Test (BAT) was evaluated using afocal size lenses to produce specific changes in retinal height. Several light scattering devices were then evaluated to determine which produced effects most similar to cataract. Contrast sensitivity and visual acuity (VA) losses were measured with each device and compared to those reported in cataract. After determining the most appropriate light scattering device, twenty healthy patients with normal visual function were recruited to perform the BAT using the filters to simulate cataract. Cataract patients were recruited from Vision America and the University of Alabama at Birmingham School of Optometry. Patients between 20 and 75 years of age with at least 20/80 VA in each eye, ≥ 2D ametropia, and normal binocular function were recruited. Stereopsis and ANK were tested and each patient completed a symptom questionnaire. ANK measurements using afocal size lenses indicated that the BAT underestimates ANK, although the effect was minimal for vertical targets and darkened surroundings, as previously reported. Based on VA and contrast sensitivity loss, Vistech scattering filters produced changes most similar to cataract. Results of the BAT using Vistech filters demonstrated that a moderate cataract but not a mild cataract may affect the ANK measurement. ANK measurements on cataract patients indicated that those with ≥ 2 D ametropia in each eye may suffer from induced ANK after the first cataract extraction. With upcoming healthcare reform, unilateral cataract extraction may be covered, but not necessarily bilateral, depending on patient VA in each eye. However, a questionnaire about symptoms at each visit in the current study showed that visual comfort did not improve after unilateral, but did improve after bilateral, cataract extraction. This indicates that quality of life should be better in bilateral cataract patients only if both cataracts are removed. This is supported by the findings of other studies. Keywords: Aniseikonia, Anisometropia, Cataract, Ametropia

Susceptibility to Fear of Heights in Bilateral Vestibulopathy and Other Disorders of Vertigo and Balance

PubMed Central

Brandt, Thomas; Grill, Eva; Strupp, Michael; Huppert, Doreen

2018-01-01

Aims: To determine the susceptibility to visual height intolerance (vHI) in patients with acquired bilateral vestibulopathy (BVP). The question was whether postural instability in BVP, which is partially compensated for by visual substitution of the impaired vestibular control of balance, leads to an increased susceptibility. This is of particular importance since fear of heights is dependent on body posture, and visual control of balance at heights can no longer substitute vestibular input. For comparison susceptibility to vHI was determined in patients with other vestibular or functional disorders. Methods: A total of 150 patients aged 18 or above who had been referred to the German Center for Vertigo and Balance Disorders and diagnosed to have BVP were surveyed with a standardized questionnaire by specifically trained neurological professionals. Further, 481 patients with other vestibular or functional disorders were included. Results: Susceptibility to vHI was reported by 29% (32 % in females, 25% in males) of the patients with BVP. Patients with vHI were slightly younger (67 vs. 71 years). Seventy percent of those with vHI reported avoidance of climbing, hiking, stairs, darkness, cycling or swimming (84% of those without vHI). Mean age for onset of vHI was 40 years. Susceptibility to vHI was higher in patients with other vertigo disorders than in those with BVP: 64% in those with phobic postural vertigo, 61% in vestibular migraine, 56% in vestibular paroxysmia, 54% in benign paroxysmal positional vertigo, 49% in unilateral vestibulopathy and 48% in Menière's disease. Conclusions: The susceptibility to vHI in BVP was not higher than that of the general population (28%).This allows two explanations that need not be alternatives but contribute to each other: (1) Patients with a bilateral peripheral vestibular deficit largely avoid exposure to heights because of their postural instability. (2) The irrational anxiety to fall from heights triggers increased susceptibility to vHI, not the objective postural instability. However, patients with BVP do not exhibit increased comorbid anxiety disorders. This view is supported by the significantly increased susceptibility to vHI in other vestibular syndromes, which are characterized by an increased comorbidity of anxiety disorders.

Bilateral simultaneous central serous chorioretinopathy in a teenage girl with systemic arterial hypertension.

PubMed

Alwassia, Ahmad A; Adhi, Mehreen; Duker, Jay S

2013-02-01

We present a case of bilateral simultaneous central serous chorioretinopathy (CSCR) in a teenage girl with a history of systemic arterial hypertension. A 19-year-old Caucasian female, with a history of systemic arterial hypertension, presented with gradual decrease in her central vision for 1 month. She was diagnosed with bilateral simultaneous CSCR, based on the findings of spectral domain optical coherence tomography (SD-OCT), indocyanine green angiography (ICG), fundus auto-fluorescence, fluorescein angiography and color fundus photographs, which are described. Blood pressure was 134/95 mmHg at presentation. Systemic evaluation failed to reveal a cause for the high blood pressure, and included a panel of blood tests, which were all normal. Her best-corrected visual acuity was 20/30 OD and 20/25 OS. Dilated fundus examination showed normal optic discs and retinal vasculature, with no evidence of hypertensive retinopathy. However, shallow retinal fluid associated with pigmentary changes was noted in the center of both maculae. OCT and ICG findings were consistent with the diagnosis of bilateral CSCR. CSCR can manifest in patients with demographics outside the range of those previously reported. This is the first report of CSCR occurring in a teenage girl, with a history of systemic arterial hypertension. It is important to consider this disease in any patient who has a clinically compatible presentation.

Cushing disease revealed by bilateral atypical central serous chorioretinopathy: case report.

PubMed

Giovansili, Iama; Belange, Georeges; Affortit, Aude

2013-01-01

We report the case of a patient with Cushing disease revealed by bilateral central serous chorioretinopathy (CSCR). We present the clinical history, physical findings, laboratory results, and imaging studies of a 53-year-old Chinese woman with a Cushing disease revealed by bilateral CSCR. The association with CSCR and the pertinent literature are reviewed. A 53-year-old patient initially presented to the Department of Ophthalmology with a 4-week history of decreased vision in the left eye. Standard ophthalmologic examination and fluorescein angiography established the diagnosis of bilateral CSCR. Systemic clinical signs and biochemical analysis indicated hypercortisolism. Magnetic resonance imaging (MRI) of the pituitary gland showed a left-side lesion compatible with a microadenoma. The diagnosis of Adrenocorticotropic hormone (ACTH)-dependent Cushing syndrome secondary to a pituitary microadenoma was selected. Endoscopic endonasal transsphenoidal surgery was performed and the pituitary adenoma was successfully removed. The histology confirmed the presence of ACTH-immunopositive pituitary adenoma. Early postoperative morning cortisol levels indicated early remission. At 6 weeks postoperatively, the patient's morning cortisol remains undetectable, and serous retinal detachments had regressed. CSCR is an uncommon manifestation of endogenous Cushing syndrome. It can be the first presentation of hypercortisolism caused by Cushing disease. CSCR should be considered when assessing patients with Cushing syndrome complaining of visual disorders. On the other hand, it is useful in patients with an atypical form of CSCR to exclude Cushing's syndrome.

Bilateral Acanthamoeba ulcer in a user of disposable soft contact lenses: a tragic incident or a consequence of the aggressive policy of soft contact lens trading?

PubMed

Sousa, Sidney Júlio de Faria E; Dias, Vanderson Glerian; Marcomini, Luís Antonio Gorla

2008-01-01

This is the report of a case of bilateral Acanthamoeba keratitis in a 19-year-old woman who bought a pair of disposable soft contact lenses in a boutique. She wore this same pair of lenses for 3 months daily without the appropriate care. This led to bilateral corneal transplantation with cataract extraction and also trabeculectomy in the right eye. When last seen, both grafts were crystal clear but the visual acuities were far from satisfactory. She also had bilateral secondary glaucoma, barely controlled by topical medication. Actually, the physical features and the wearing time characteristics of the disposable soft contact lenses created unprecedented difficulties to the medical surveillance of their wearers. Without the right assistance they tend to become careless regarding routine cleaning. They also feel free to buy less expensive lenses, to use saline instead of lens solutions, to violate the limits of wearing time and to extend the use over the sleeping period. Additionally, the aggressive marketing and the wide distribution of these lenses increase the chances that economically or educationally unprepared people will acquire them. The question that remains is: Is the present case an accidental event or an example of what is likely to happen in the future if the indiscriminate selling of disposable soft contact lenses continues to evolve?

Correlation of macular structure and function in a boy with primary foveomacular retinitis and sequence of changes over 5 years.

PubMed

Badhani, Anurag; Padhi, Tapas Ranjan; Panda, Gopal Krishna; Mukherjee, Sujoy; Das, Taraprasad; Jalali, Subhadra

2017-08-01

To describe the clinical characteristics, macular structure and function, and to document sequential changes over 5 years in a 10-year-old boy with bilateral primary foveomacular retinitis. A 10-year-old boy presented with sudden onset scotoma in both eyes, experienced after getting up from bed on a non-eclipse day. He persistently denied direct sun-gazing. He neither had any significant systemic illness, nor was using any medications. In addition to a detailed examination at presentation that included fundus fluorescein angiogram (FFA), electroretinogram (ERG), pattern ERG and electrooculogram (EOG), he was examined periodically for 5 years with Humphrey visual field (HVF), spectral domain optical coherence tomogram (SDOCT), Amsler grid charting and multifocal ERG. The macular structure and functions were analyzed over the years and correlated with the symptoms. All findings were bilaterally symmetrical at each visit. At presentation, his corrected visual acuity was 20/25 with subfoveal yellow dot similar to solar retinopathy, central scotoma with reduced foveal threshold in HVF 24-2, micropsia in Amsler grid, missing of two plates on Ishihara color vision chart, transfoveal full thickness hyper-reflective band on SD OCT, unremarkable FFA and normal foveal peak in mfERG. The flash ERG and EOG were unremarkable. A month later, his VA improved to 20/20, he had relative scotoma in Amsler grid, no scotoma in HVF (10-2), restoration of the inner segment of the photoreceptors with sharp defect involving ellipsoid and photoreceptor interdigitation zone in SDOCT and blunting of foveal peaks in mfERG. Three months later, his corrected VA was 20/20 with relative scotoma in Amsler grid, normal color vision, no scotoma in HVF 10-2 and unchanged SDOCT findings. In subsequent examinations at 6, 9, 14, 29, 39 and 60 months, he was symptomless with VA 20/20, unremarkable fundus, normal Amsler grid and HVF (normal foveal threshold), unchanged SDOCT findings and the reduced foveal peaks on mfERG in both eyes got normalized only at 60 months. Presented here is a case of bilaterally symmetrical idiopathic foveomacular retinitis that had a clinical appearance similar to solar retinopathy. The fundus changes persisted for 4 weeks, the symptoms and changes in Amsler grid lasted for 3 months, and the foveal threshold in visual fields normalized within 3 months. Maximum change in the SDOCT defect occurred within a month, and the extrafoveal defect in the ellipsoid and photoreceptor interdigitation line persisted despite resolution of symptoms and resolution of the visual field defect and normal distance vision. Probably, the foveal lesion detected on SDOCT was too small to cause a reduction in the distance visual acuity or show up in the visual field and mfERG later.

Dynamic Visual Acuity While Walking in Normals and Labyrinthine-Deficient Patients

NASA Technical Reports Server (NTRS)

Hillman, Edward J.; Bloomberg, Jacob J.; McDonald, P. Vernon; Cohen, Helen S.

1996-01-01

We describe a new, objective, easily administered test of dynamic visual acuity (DVA) while walking. Ten normal subjects and five patients with histories of severe bilateral vestibular dysfunctions participated in this study. Subjects viewed a visual display of numerals of different font sizes presented on a laptop computer while they stood still and while they walked on a motorized treadmill. Treadmill speed was adapted for 4 of 5 patients. Subjects were asked to identify the numerals as they appeared on the computer screen. Test results were reasonably repeatable in normals. The percent correct responses at each font size dropped slightly while walking in normals and dropped significantly more in patients. Patients performed significantly worse than normals while standing still and while walking. This task may be useful for evaluating post-flight astronauts and vestibularly impaired patients.

Declining vision: saved by a tracheostomy.

PubMed

Hett, Kirsty L; Chutter, Lily J; Hassan, Mohamed; Okosieme, Onyebuchi E

2013-10-07

A 37-year-old woman presented to our hospital with a history of headaches, blurred vision and declining visual acuity. She had a history of obstructive sleep apnoea associated with Treacher Collins syndrome, a rare congenital disorder characterised by craniofacial deformities and obstruction of the upper airways. On funduscopy we noted bilateral papilloedema and retinal haemorrhages. A CT scan of the brain excluded a space occupying lesion and contrast-enhanced CT did not show evidence of venous sinus thrombosis. The cerebrospinal fluid opening pressure on lumbar puncture was normal. We made a diagnosis of visual loss and papilloedema secondary to chronic CO2 retention from obstructive sleep apnoea. Her vision and headaches improved remarkably following a permanent tracheostomy. This case highlights the association between obstructive sleep apnoea and papilloedema and shows that the associated visual loss can ultimately be restored with a tracheostomy.

Perceptual deficits of object identification: apperceptive agnosia.

PubMed

Milner, A David; Cavina-Pratesi, Cristiana

2018-01-01

It is argued here that apperceptive object agnosia (generally now known as visual form agnosia) is in reality not a kind of agnosia, but rather a form of "imperception" (to use the term coined by Hughlings Jackson). We further argue that its proximate cause is a bilateral loss (or functional loss) of the visual form processing systems embodied in the human lateral occipital cortex (area LO). According to the dual-system model of cortical visual processing elaborated by Milner and Goodale (2006), area LO constitutes a crucial component of the ventral stream, and indeed is essential for providing the figural qualities inherent in our normal visual perception of the world. According to this account, the functional loss of area LO would leave only spared visual areas within the occipito-parietal dorsal stream - dedicated to the control of visually-guided actions - potentially able to provide some aspects of visual shape processing in patients with apperceptive agnosia. We review the relevant evidence from such individuals, concentrating particularly on the well-researched patient D.F. We conclude that studies of this kind can provide useful pointers to an understanding of the processing characteristics of parietal-lobe visual mechanisms and their interactions with occipitotemporal perceptual systems in the guidance of action. Copyright © 2018 Elsevier B.V. All rights reserved.

Behavioral and Neural Representations of Spatial Directions across Words, Schemas, and Images.

PubMed

Weisberg, Steven M; Marchette, Steven A; Chatterjee, Anjan

2018-05-23

Modern spatial navigation requires fluency with multiple representational formats, including visual scenes, signs, and words. These formats convey different information. Visual scenes are rich and specific but contain extraneous details. Arrows, as an example of signs, are schematic representations in which the extraneous details are eliminated, but analog spatial properties are preserved. Words eliminate all spatial information and convey spatial directions in a purely abstract form. How does the human brain compute spatial directions within and across these formats? To investigate this question, we conducted two experiments on men and women: a behavioral study that was preregistered and a neuroimaging study using multivoxel pattern analysis of fMRI data to uncover similarities and differences among representational formats. Participants in the behavioral study viewed spatial directions presented as images, schemas, or words (e.g., "left"), and responded to each trial, indicating whether the spatial direction was the same or different as the one viewed previously. They responded more quickly to schemas and words than images, despite the visual complexity of stimuli being matched. Participants in the fMRI study performed the same task but responded only to occasional catch trials. Spatial directions in images were decodable in the intraparietal sulcus bilaterally but were not in schemas and words. Spatial directions were also decodable between all three formats. These results suggest that intraparietal sulcus plays a role in calculating spatial directions in visual scenes, but this neural circuitry may be bypassed when the spatial directions are presented as schemas or words. SIGNIFICANCE STATEMENT Human navigators encounter spatial directions in various formats: words ("turn left"), schematic signs (an arrow showing a left turn), and visual scenes (a road turning left). The brain must transform these spatial directions into a plan for action. Here, we investigate similarities and differences between neural representations of these formats. We found that bilateral intraparietal sulci represent spatial directions in visual scenes and across the three formats. We also found that participants respond quickest to schemas, then words, then images, suggesting that spatial directions in abstract formats are easier to interpret than concrete formats. These results support a model of spatial direction interpretation in which spatial directions are either computed for real world action or computed for efficient visual comparison. Copyright © 2018 the authors 0270-6474/18/384996-12$15.00/0.

Evidence that primary visual cortex is required for image, orientation, and motion discrimination by rats.

PubMed

Petruno, Sarah K; Clark, Robert E; Reinagel, Pamela

2013-01-01

The pigmented Long-Evans rat has proven to be an excellent subject for studying visually guided behavior including quantitative visual psychophysics. This observation, together with its experimental accessibility and its close homology to the mouse, has made it an attractive model system in which to dissect the thalamic and cortical circuits underlying visual perception. Given that visually guided behavior in the absence of primary visual cortex has been described in the literature, however, it is an empirical question whether specific visual behaviors will depend on primary visual cortex in the rat. Here we tested the effects of cortical lesions on performance of two-alternative forced-choice visual discriminations by Long-Evans rats. We present data from one highly informative subject that learned several visual tasks and then received a bilateral lesion ablating >90% of primary visual cortex. After the lesion, this subject had a profound and persistent deficit in complex image discrimination, orientation discrimination, and full-field optic flow motion discrimination, compared with both pre-lesion performance and sham-lesion controls. Performance was intact, however, on another visual two-alternative forced-choice task that required approaching a salient visual target. A second highly informative subject learned several visual tasks prior to receiving a lesion ablating >90% of medial extrastriate cortex. This subject showed no impairment on any of the four task categories. Taken together, our data provide evidence that these image, orientation, and motion discrimination tasks require primary visual cortex in the Long-Evans rat, whereas approaching a salient visual target does not.

Processing of visual semantic information to concrete words: temporal dynamics and neural mechanisms indicated by event-related brain potentials( ).

PubMed

van Schie, Hein T; Wijers, Albertus A; Mars, Rogier B; Benjamins, Jeroen S; Stowe, Laurie A

2005-05-01

Event-related brain potentials were used to study the retrieval of visual semantic information to concrete words, and to investigate possible structural overlap between visual object working memory and concreteness effects in word processing. Subjects performed an object working memory task that involved 5 s retention of simple 4-angled polygons (load 1), complex 10-angled polygons (load 2), and a no-load baseline condition. During the polygon retention interval subjects were presented with a lexical decision task to auditory presented concrete (imageable) and abstract (nonimageable) words, and pseudowords. ERP results are consistent with the use of object working memory for the visualisation of concrete words. Our data indicate a two-step processing model of visual semantics in which visual descriptive information of concrete words is first encoded in semantic memory (indicated by an anterior N400 and posterior occipital positivity), and is subsequently visualised via the network for object working memory (reflected by a left frontal positive slow wave and a bilateral occipital slow wave negativity). Results are discussed in the light of contemporary models of semantic memory.

Macular Hole Development After Vitrectomy for Floaters: A Case Report.

PubMed

Appeltans, Andrea; Mura, Marco; Bamonte, Giulio

2017-12-01

The purpose of this report is to describe a case of macular hole development after vitrectomy for floaters with induction of posterior vitreous detachment. A 44-year-old otherwise healthy man presented with visually debilitating floaters in his right eye; these had been present for more than 2 years. Preoperative examination was unremarkable in both eyes, apart from some degree of vitreous degeneration in the right eye. Preoperative visual acuity was 20/20 bilaterally. A 25-gauge transconjunctival sutureless pars plana complete vitrectomy with induction of posterior vitreous detachment was performed in the right eye. Upon examination 1 month after surgery, a small full-thickness macular hole was detected in the right eye. Visual acuity was diminished to 20/80. The macular hole was closed after a second vitrectomy with internal limiting membrane peeling and gas tamponade. Macular hole development should be listed as a possible complication of vitrectomy for visually debilitating floaters when a posterior vitreous detachment is induced during surgery.

Audiovisual Association Learning in the Absence of Primary Visual Cortex.

PubMed

Seirafi, Mehrdad; De Weerd, Peter; Pegna, Alan J; de Gelder, Beatrice

2015-01-01

Learning audiovisual associations is mediated by the primary cortical areas; however, recent animal studies suggest that such learning can take place even in the absence of the primary visual cortex. Other studies have demonstrated the involvement of extra-geniculate pathways and especially the superior colliculus (SC) in audiovisual association learning. Here, we investigated such learning in a rare human patient with complete loss of the bilateral striate cortex. We carried out an implicit audiovisual association learning task with two different colors of red and purple (the latter color known to minimally activate the extra-genicular pathway). Interestingly, the patient learned the association between an auditory cue and a visual stimulus only when the unseen visual stimulus was red, but not when it was purple. The current study presents the first evidence showing the possibility of audiovisual association learning in humans with lesioned striate cortex. Furthermore, in line with animal studies, it supports an important role for the SC in audiovisual associative learning.

Oxaliplatin-Related Ocular Toxicity

PubMed Central

Mesquida, Marina; Sanchez-Dalmau, Bernardo; Ortiz-Perez, Santiago; Pelegrín, Laura; Molina-Fernandez, Juan José; Figueras-Roca, Marc; Casaroli-Marano, Ricardo; Adán, Alfredo

2010-01-01

We report the case of a 52-year-old woman with advanced colorectal cancer who was treated with oxaliplatin on a FOLFOX schedule. After 3 cycles of chemotherapy, she started to complain of visual loss, altered color vision and neurological symptoms. Due to the suspicion of ocular and neurological toxicity, antineoplastic treatment was stopped. Her visual field showed a concentric bilateral scotoma and the electrooculogram test revealed severe impairment of the retinal pigment epithelium. Visual acuity, color vision and visual field recovered completely 8 months later, although electrooculogram remained abnormal. Ocular toxicity has been reported as an infrequent adverse event of oxaliplatin. Findings in this case indicate toxicity of this chemotherapeutic agent on the retinal pigment epithelium, which has not been reported before. This damage could be permanent, and it thus differs from previously described oxaliplatin-induced ocular toxicities, which are usually transient and reversible. With increasing use of oxaliplatin as first-line treatment in advanced colorectal cancer, we have to be aware of this possible toxicity. PMID:21151636

[Importance of family examination in juvenile X-linked retinoschisis].

PubMed

Kłosowska-Zawadka, A; Bernardczyk-Meller, J; Gotz-Wieckowska, A; Krawczyński, M

2005-12-01

Congenital (juvenile) retinoschisis belongs to the group of hereditary vitreoretinopathies. This disorder is inherited in an X-linked recessive pattern and its onset usually occurs in 5- to 10-year-old boys. Presenting clinical signs include decreased visual acuity due to maculopathy. The authors present a case of a 17-year-old boy with decreased visual acuity, hypermetropia, and bilateral retinoschisis with maculopathy upon fundus examination. In view of a 50% risk of the disorder occurring in the brothers of the affected male, they underwent full ophthalmological and electrophysiological examinations (until then asymptomatic). In one of them decreased visual acuity, mixed astigmatism, and maculopathy were present, without any changes of the peripheral retina. In the youngest brother decreased visual acuity, hypermetropia, and maculopathy were diagnosed. Genetic counseling and ophthalmological examination of family members at risk facilitated early recognition of the pathological changes in the siblings. Genetic counseling with pedigree analysis and genetic analysis, if possible, should be offered to all affected patients and family members.

The role of convexity in perception of symmetry and in visual short-term memory.

PubMed

Bertamini, Marco; Helmy, Mai Salah; Hulleman, Johan

2013-01-01

Visual perception of shape is affected by coding of local convexities and concavities. For instance, a recent study reported that deviations from symmetry carried by convexities were easier to detect than deviations carried by concavities. We removed some confounds and extended this work from a detection of reflection of a contour (i.e., bilateral symmetry), to a detection of repetition of a contour (i.e., translational symmetry). We tested whether any convexity advantage is specific to bilateral symmetry in a two-interval (Experiment 1) and a single-interval (Experiment 2) detection task. In both, we found a convexity advantage only for repetition. When we removed the need to choose which region of the contour to monitor (Experiment 3) the effect disappeared. In a second series of studies, we again used shapes with multiple convex or concave features. Participants performed a change detection task in which only one of the features could change. We did not find any evidence that convexities are special in visual short-term memory, when the to-be-remembered features only changed shape (Experiment 4), when they changed shape and changed from concave to convex and vice versa (Experiment 5), or when these conditions were mixed (Experiment 6). We did find a small advantage for coding convexity as well as concavity over an isolated (and thus ambiguous) contour. The latter is consistent with the known effect of closure on processing of shape. We conclude that convexity plays a role in many perceptual tasks but that it does not have a basic encoding advantage over concavity.

Back pain: a real target for spinal cord stimulation?

PubMed

Rigoard, Philippe; Delmotte, Alexandre; D'Houtaud, Samuel; Misbert, Lorraine; Diallo, Bakari; Roy-Moreau, Aline; Durand, Sylvain; Royoux, Solène; Giot, Jean-Philippe; Bataille, Benoit

2012-03-01

Failed back surgery syndrome represents one of the most frequent etiologies of chronic back pain and is a major public health issue. Neurostimulation has currently not been validated in the treatment of back pain because of technological limitations in implantable spinal cord stimulation (SCS) systems. New-generation leads using several columns of stimulation can generate longitudinal and/or transverse stimulation fields into the spinal cord. To investigate, through extensive stimulation testing, the capacity of multicolumn tripolar leads to achieve back territory paresthesia coverage in refractory failed back surgery syndrome patients. Eleven patients implanted with a 16-contact spinal cord stimulation lead (Specify 5-6-5, Medtronic Inc) were assessed with a systematic exploration of 43 selected stimulation configurations to generate bilateral back paresthesia in addition to leg territory coverage. The tripolar lead successfully generated paresthesia in both bilateral back and leg territories in 9 patients (81.8%). Success rates of multicolumn stimulation patterns were significantly higher than for longitudinal configurations for lombodorsal paresthesia coverage. Six months after implantation, significant pain relief was obtained compared with preoperative evaluation for global pain (Visual Analog Scale, 2.25 vs 8.2 preoperatively; P < .05), leg pain (Visual Analog Scale, 0.5 vs 7.6 preoperatively; P < .05), and back pain (Visual Analog Scale, 1.5 vs 7.8 preoperatively; P < .05). These results suggest that multicolumn leads can reliably generate back pain coverage and favor pain relief outcomes. This may lead physicians to reconsider new indications for spinal cord stimulation. Expanding neurostimulation perspectives to intractable back pain syndromes could become realistic in the near future.