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Sample records for acute central retinal

  1. Presentation of acute central retinal vein occlusion in scleroderma

    PubMed Central

    Malik, Faisal; Al Habash, Ahmed

    2014-01-01

    Central retinal vein occlusion (CRVO) is a rare complication of scleroderma. Here we report a case of a 30-year-old man who was diagnosed to have scleroderma in the rheumatology and dermatology clinic. During treatment with systemic steroids and immunosuppressive therapy the patient developed a sudden decrease of vision in the right eye and was diagnosed to have right CRVO with macular edema on fundus examination. After three consecutive Intravitreal bevacizumab (IVB) injections for macular edema, best-corrected visual acuity (BCVA) improved from 20/80 to 20/25. All ocular and systemic causes of CRVO other than scleroderma were excluded in our patient by thorough clinical examination and investigations, suggesting that scleroderma was the most possible etiology in his condition. PMID:25892936

  2. Incidence and Clinical Features of Neovascularization of the Iris following Acute Central Retinal Artery Occlusion

    PubMed Central

    Jung, Young Ho; Ahn, Seong Joon; Hong, Jeong-Ho; Park, Kyu Hyung; Han, Moon-Ku; Jung, Cheolkyu

    2016-01-01

    Purpose To investigate the incidence of neovascularization of the iris (NVI) and clinical features of patients with NVI following acute central retinal artery occlusion (CRAO). Methods A retrospective review of 214 consecutive CRAO patients who visited one tertiary hospital between January 2009 and January 2015 was conducted. In total, 110 patients were eligible for this study after excluding patients with arteritic CRAO, a lack of follow-up, iatrogenic CRAO secondary to cosmetic filler injection, or NVI detected before CRAO attack. Fluorescein angiography (FA) was applied until retinal arterial reperfusion was achieved, typically within 1 to 3 months. Results The incidence of NVI was 10.9% (12 out of 110 patients). Neovascular glaucoma was found in seven patients (6.4%). The mean time to NVI diagnosis after CRAO events was 3.0 months (range, 1 week to 15 months). The cumulative incidence was 5.5% at 3 months, 7.3% at 6 months, and 10.9% at 15 months. Severely narrowed ipsilateral carotid arteries were observed in only three patients (27.3%). The other nine patients (75.0%) showed no predisposing conditions for NVI, such as proliferative diabetic retinopathy or central retinal vein occlusion. Reperfusion rate and prevalence of diabetes were significantly different between patients with NVI and patients without NVI (reperfusion: 0% [NVI] vs. 94.7% [no NVI], p < 0.001; diabetes: 50.0% [NVI] vs. 17.3% [no NVI], p = 0.017). Conclusions CRAO may lead to NVI and neovascular glaucoma caused by chronic retinal ischemia from reperfusion failure. Our results indicate that follow-up fluorescein angiography is important to evaluate retinal artery reperfusion after acute CRAO events, and that prophylactic treatment such as panretinal photocoagulation should be considered if retinal arterial perfusion is not recovered. PMID:27729755

  3. Central Retinal Vein Occlusion and Paracentral Acute Middle Maculopathy Diagnosed With En Face Optical Coherence Tomography.

    PubMed

    Phasukkijwatana, Nopasak; Rahimi, Mansour; Iafe, Nicholas; Sarraf, David

    2016-09-01

    A 21-year-old healthy female presented with acute-onset vision loss in the left eye. Multimodal imaging, including fundus photography and fluorescein angiography, was unremarkable. En face optical coherence tomography (OCT) demonstrated paracentral acute middle maculopathy (PAMM) lesions in a perivenular fern-like pattern leading to the diagnosis of central retinal vein occlusion (CRVO). En face OCT can be an important modality to identify the distribution of abnormalities of the middle retina such as PAMM. The distribution of PAMM lesions in the posterior pole will be a critical element in the determination of the etiologic disorder. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:862-864.]. PMID:27631483

  4. Bilateral central retinal artery occlusion associated with herpes simplex virus-associated acute retinal necrosis and meningitis: case report and literature review.

    PubMed

    Weissman, Heather M; Biousse, Valerie; Schechter, Marcos Coutinho; Del Rio, Carlos; Yeh, Steven

    2015-02-01

    A 60-year-old woman with a history of recurrent headaches and blurred vision presented with bilateral optic disc edema. Optic neuritis was suspected, and intravenous methylprednisonlone was administered. Her vision declined to hand motions in both eyes, and subsequent evaluation revealed bilateral acute retinal necrosis with bilateral central retinal artery occlusions (CRAO). Aqueous humor polymerase chain reaction analysis was positive for herpes simplex virus (HSV), establishing a diagnosis of HSV-associated bilateral acute retinal necrosis (ARN) and meningitis. CRAO has rarely been reported in association with ARN, and a fulminant course with bilateral CRAO in association with ARN has not been previously reported. This case emphasizes the importance of careful peripheral examination in patients with presumptive optic neuritis, judicious use of systemic corticosteroid in this context, and the retinal vaso-obliterative findings that may be observed in the pathogenesis of ARN.

  5. ACUTE RETINAL ARTERIAL OCCLUSIVE DISORDERS

    PubMed Central

    Hayreh, Sohan Singh

    2011-01-01

    The initial section deals with basic sciences; among the various topics briefly discussed are the anatomical features of ophthalmic, central retinal and cilioretinal arteries which may play a role in acute retinal arterial ischemic disorders. Crucial information required in the management of central retinal artery occlusion (CRAO) is the length of time the retina can survive following that. An experimental study shows that CRAO for 97 minutes produces no detectable permanent retinal damage but there is a progressive ischemic damage thereafter, and by 4 hours the retina has suffered irreversible damage. In the clinical section, I discuss at length various controversies on acute retinal arterial ischemic disorders. Classification of acute retinal arterial ischemic disorders These are of 4 types: CRAO, branch retinal artery occlusion (BRAO), cotton wools spots and amaurosis fugax. Both CRAO and BRAO further comprise multiple clinical entities. Contrary to the universal belief, pathogenetically, clinically and for management, CRAO is not one clinical entity but 4 distinct clinical entities – non-arteritic CRAO, non-arteritic CRAO with cilioretinal artery sparing, arteritic CRAO associated with giant cell arteritis (GCA) and transient non-arteritic CRAO. Similarly, BRAO comprises permanent BRAO, transient BRAO and cilioretinal artery occlusion (CLRAO), and the latter further consists of 3 distinct clinical entities - non-arteritic CLRAO alone, non-arteritic CLRAO associated with central retinal vein occlusion and arteritic CLRAO associated with GCA. Understanding these classifications is essential to comprehend fully various aspects of these disorders. Central retinal artery occlusion The pathogeneses, clinical features and management of the various types of CRAO are discussed in detail. Contrary to the prevalent belief, spontaneous improvement in both visual acuity and visual fields does occur, mainly during the first 7 days. The incidence of spontaneous visual

  6. Hyperhomocysteinemia, a Biochemical Tool for Differentiating Ischemic and Nonischemic Central Retinal Vein Occlusion during the Early Acute Phase

    PubMed Central

    Mukherjee, Somnath; Ghosh, Sambuddha; Mukherjee, Suman; Dutta, Jayanta; Datta, Himadri; Das, Harendra Nath

    2015-01-01

    Purpose The purpose of the study was to differentiate ischemic central retinal vein occlusion (CRVO) from nonischemic CRVO during the early acute phase using plasma homocysteine as a biochemical marker. Methods Fasting plasma homocysteine, serum vitamin B12, and folate levels were measured in 108 consecutive unilateral elderly adult (age >50 years) ischemic CRVO patients in the absence of local and systemic disease and compared with a total of 144 age and sex matched nonischemic CRVO patients and 120 age and sex matched healthy control subjects. Results Homocysteine level was significantly increased in the patients with ischemic CRVO in comparison with nonischemic CRVO patients (p = 0.009) and also in comparison with control subjects (p < 0.001). Analysis also showed that hyperhomocysteinemia was associated with increased incidence of ischemic CRVO (odds ratio, 18) than that for nonischemic CRVO (odds ratio, 4.5). Serum vitamin B12 and folate levels were significantly lower (p < 0.001) in CRVO patients compared to the control but were not significantly different between nonischemic and ischemic CRVO patients (p > 0.1). Conclusions Hyperhomocysteinemia can be regarded as useful in differentiating nonischemic and ischemic CRVO during the early acute phase in absence of local and systemic disease in the elderly adult (age >50 years) population. PMID:25829824

  7. Hemi-central retinal artery occlusion in young adults

    PubMed Central

    Rishi, Pukhraj; Rishi, Ekta; Sharma, Tarun; Mahajan, Sheshadri

    2010-01-01

    Amongst the clinical presentations of retinal artery occlusion, hemi-central retinal artery occlusion (Hemi-CRAO) is rarely described. This case series of four adults aged between 22 and 36 years attempts to describe the clinical profile, etiology and management of Hemi-CRAO. Case 1 had an artificial mitral valve implant. Polycythemia and malignant hypertension were noted in Case 2. The third patient had Leiden mutation while the fourth patient had Eisenmenger’s syndrome. Clinical examination and fundus fluorescein angiography revealed a bifurcated central retinal artery at emergence from the optic nerve head, in all cases. Color Doppler examination of the central retinal artery confirmed branching of the artery behind the lamina cribrosa. It is hypothesized that bifurcation of central retinal artery behind the lamina cribrosa may predispose these hemi-trunks to develop an acute occlusion if associated with underlying risk factors. The prognosis depends upon arterial recanalisation and etiology of the thromboembolic event. PMID:20689202

  8. Surgical treatment of central retinal vein occlusion.

    PubMed

    Berker, Nilufer; Batman, Cosar

    2008-05-01

    The treatment of central retinal vein occlusion (CRVO) is still a subject of debate. Medical therapy efforts, as well as retinal laser photocoagulation, have mostly dealt with management of the sequelae of CRVO, and have shown limited success in improving visual acuity. The unsatisfactory results of such therapeutic efforts led to the development of new treatment strategies focused on the surgical treatment of the occluded retinal vein. The purpose of this review is to summarize the outcomes of commonly reported surgical treatment strategies and to review different opinions on the various surgical approaches to the treatment of CRVO.

  9. Retinal fractals and acute lacunar stroke.

    PubMed

    Cheung, Ning; Liew, Gerald; Lindley, Richard I; Liu, Erica Y; Wang, Jie Jin; Hand, Peter; Baker, Michelle; Mitchell, Paul; Wong, Tien Y

    2010-07-01

    This study aimed to determine whether retinal fractal dimension, a quantitative measure of microvascular branching complexity and density, is associated with lacunar stroke. A total of 392 patients presenting with acute ischemic stroke had retinal fractal dimension measured from digital photographs, and lacunar infarct ascertained from brain imaging. After adjusting for age, gender, and vascular risk factors, higher retinal fractal dimension (highest vs lowest quartile and per standard deviation increase) was independently and positively associated with lacunar stroke (odds ratio [OR], 4.27; 95% confidence interval [CI], 1.49-12.17 and OR, 1.85; 95% CI, 1.20-2.84, respectively). Increased retinal microvascular complexity and density is associated with lacunar stroke.

  10. NONICHEMIC CENTRAL RETINAL VEIN OCCLUSION ASSOCIATED WITH HEREDITARY THROMBOPHYLIA.

    PubMed

    Fişuş, Andreea Dana; Pop, Doina Suzana; Rusu, Monica Blanka; Vultur, Florina; Horvath, Karin Ursula

    2015-01-01

    Retinal vein occlusion (RVO) is the second most common retinal vein disease with significant visual loss via thrombus or compression of vein wall. Thrombophilia is the predisposition to vascular thrombosis with the existence of genetic defect that leads to blood hypercoagulability. This report describes the case of a 55 year old male patient, with an active life who presented himself at the emergency room with acute visual lose, insidious and progressive visual field constriction, without any known history of neurological or vascular diseases. The examinations revealed unilateral optic nerve head edema, the fluorescein angiography was specific for nonischemic central retinal vein occlusion CRVO complicated with macular edema. Blood examinations has emphasized the presence of the heterozygous mutation A1298C in the methylenetetrahydrofolate reductase gene (MTHFR), the only one presented from the thrombophilia screen panel and a slightly elevated cholesterol level. During the follow-up period, the patient received anti-VEGF treatment (Bevacizumab, 3x 0.1 ml intravitreal injections) with improved visual acuity and amendment of macular edema. The complex etiology calls for interdisciplinary approach to determine better the cause of this ophthalmological disease. Although studies have found a correlation between some thrombophilia mutations and retinal vein occlusion, more studies that contain a larger number of patients are necessary in order to determine the final role of these gene variants.

  11. Central serous choroidopathy with bullous retinal detachment.

    PubMed

    Tsukahara, I; Uyama, M

    1978-05-16

    We report here a new type of secondary retinal detachment that has never been clearly defined. The characteristic features of the disease are: (1) prevalence in middle-aged males, (2) bilateral involvement, (3) frequent existence of prodromal lesions that over long periods resemble central serous retinopathy, (4) in the evolution stage, appearance of multiple yellowish white exudative flecks of one-half to one disc in diameter at or near the posterior pole of the fundus, (5) fluorescein studies revealing pronounced leakage of dye from the choroid into the subretinal space at the sites of exudates, (6) retinal detachment of various degrees with shifting subretinal fluid and without tears, (7) no evidence of intraocular inflammation, (8) no filling abnormalities seen in the choroidal fluorescence, (9) no response to medical therapy, including steroids and antibiotics, (10) photocoagulation to leakage sites leading to rapid resolution of retinal detachment; otherwise, spontaneous healing of detachment occurring within about 7-9 months, leaving fibroblastic macular scars and marked visual loss, and (11) no evidence of systemic findings that may be of etiologic significance. From this characteristic clinical picture, the idea of a new clinical entity must be considered. Our findings in 35 eyes from 18 Japanese patients are discussed.

  12. An unusual central retinal dystrophy associated with ichthyosis vulgaris.

    PubMed

    Saatci, O A; Ozbek, Z; Köse, S; Durak, I; Kavukçu, S

    2000-06-01

    A number of ichthyosis syndromes may have retinal abnormalities such as the retinitis pigmentosa-like diffuse rod-cone dystrophy in Refsum's syndrome and the maculopathy in Sjögren-Larsson syndrome. We present two sisters who have an unusual, almost identical, bilaterally symmetric central retinal dystrophy associated with ichthyosis vulgaris in the absence of other systemic disorders. We believe that this dystrophy has not been previously described in patients with any of the known varieties of ichthyosis.

  13. Catastrophic antiphospholipid syndrome presenting as bilateral central retinal artery occlusions.

    PubMed

    Saraf, Steven S; Patel, Yogin P; Desai, Ankit; Desai, Uday R

    2015-01-01

    A previously healthy 22-year-old African American woman presented with bilateral vision loss associated with headache. Her ocular examination was significant for bilateral retinal arterial "boxcarring," retinal whitening, retinal hemorrhages, and cherry red spots. She was diagnosed with bilateral central retinal artery occlusions and was hospitalized due to concomitant diagnosis of stroke and hypercoagulable state. She was also found to be in heart failure and kidney failure. Rheumatology was consulted and she was diagnosed with catastrophic antiphospholipid syndrome in association with systemic lupus erythematosus. Approximately 7 months after presentation, the patient's vision improved and remained stable at 20/200 and 20/80. PMID:25722904

  14. Retino-choroidal ischemia in central retinal vein occlusion

    PubMed Central

    Hussain, Nazimul; Hussain, Anjli

    2014-01-01

    A 41-year-old gentleman with insulin dependent diabetes had decreased vision in the right eye due to non-ischemic central retinal vein occlusion with macular edema. One month following intravitreal ranibizumab, he developed retino-choroidal ischemia with further loss of vision. Authors show the fluorescein angiographic transition from non-ischemic central retinal vein occlusion to retino-choroidal ischemia. PMID:25473353

  15. [Retinal vein occlusion management algorithm. Part 1. Classification, diagnosis, and acute-stage treatment].

    PubMed

    Budzinskaya, M V; Mazurina, N K; Egorov, A E; Kuroedov, A V; Loskutov, I A; Plyukhova, A A; Razik, S; Ryabtseva, A A; Simonova, S V

    2015-01-01

    Considering an upward global trend in cardiovascular disease rates, retinal vein occlusion (RVO) in particular, development of therapeutic guidelines is a pressing issue in ophthalmology. Risk factors for RVO include hypertension, atherosclerosis, diabetes mellitus, blood disorders, inflammatory disorders, and prescription drug use. Three stages of RVO have been identified. By location, the entity can be divided into three big groups: central retinal vein occlusion (CRVO), branch retinal vein occlusion (BRVO), and hemicentral retinal vein occlusion (HCRVO), each being either ischemic or nonischemic. Functional prognosis is better in nonischemic occlusions. Patient management comprises acute-stage treatment (anticoagulants, fibrinolytic agents, and hemodilution) and struggling with ocular complications (intravitreal injections and laser coagulation). It is essential that primary assessment and follow-up of patients at any stage of RVO include optical coherence tomography and fluorescent angiography. PMID:26977727

  16. A traveling "spot sign" in recurrent amaurosis fugax and central retinal artery occlusion.

    PubMed

    Nedelmann, Max; Tanislav, Christian; Kaps, Manfred

    2014-10-01

    Sudden monocular blindness is frequently caused by central retinal artery occlusion (CRAO) from embolic sources. Treatment options are insufficient, and spontaneous prognosis toward visual recovery is poor. In addition to ophthalmologic evaluation, transorbital sonographic assessment of the central retinal artery may help establish early diagnosis by Doppler sonographic proof of occlusion and, in some cases, by B-mode detection of an intra-arterial "spot sign". We report the case of a patient with recurrent amaurosis fugax and subsequent CRAO. Ultrasound examination after 2 incidences of amaurosis fugax demonstrated a patent but stenotic central retinal artery, with stenosis caused by an embolus visualized as a "spot sign". The following day, persisting amaurosis suddenly developed. Sonographic re-evaluation revealed downstream dislodgment of the "spot sign" and complete arterial occlusion. Thrombolytic treatment did not result in clinical improvement. In conclusion, this case report describes a single case of repeated amaurosis fugax and deterioration to CRAO via embolization into the central retinal artery and consecutive downstream dislodgment. It emphasizes that ultrasound may render valuable diagnostic information in patients with acute central retinal artery embolization toward its embolic etiology and its risk of subsequent deterioration. PMID:24957310

  17. Intra-arterial thrombolysis for central retinal artery occlusion: two cases report.

    PubMed

    Hwang, Gyojun; Woo, Se Joon; Jung, Cheolkyu; Park, Kyu Hyung; Hwang, Jeong-Min; Kwon, O-Ki

    2010-06-01

    Central retinal artery occlusion (CRAO) causes severe visual loss in affected eye and vision does not recover in more than 90% of the patients. It is believed that it occurs by occlusion of the central retinal artery with small emboli from atherosclerotic plaque of internal cerebral artery. Retina is a part of the brain, thus basically CRAO is corresponding to acute occlusion of intracerebral artery and retinal ischemia is to cerebral stroke. Therefore, intra-arterial thrombolysis (IAT) has been considered as a treatment method in CRAO. Recently, we treated 2 patients diagnosed as CRAO and could achieve complete recanalization on fundus fluorescein angiogram with IAT. Of them, one recovered visual acuity to 20/25. We report our 2 CRAO cases treated with IAT and discuss technical aspects for IAT and management of patient. To the best of our knowledge, this is the first Korean report of IAT for CRAO. PMID:20514326

  18. SURGICAL EMBOLECTOMY FOR FOVEA-THREATENING ACUTE RETINAL ARTERY OCCLUSION

    PubMed Central

    Almeida, David R.P.; Mammo, Zaid; Chin, Eric K.

    2016-01-01

    Purpose: To describe a technique of surgical intraocular embolectomy in patients with acute fovea-threatening branch retinal artery occlusion. Methods: Pars plana vitrectomy with embolectomy involving embolus isolation, dissection, and removal in patients with an acute fovea-threatening arterial occlusion without a patent cilioretinal artery. Results: The surgical technique involves a core vitrectomy. The blocked artery is incised using a microvitreoretinal blade, and microsurgical forceps are used to retrieve the embolus. No significant complications were noted. The study technique offers an excellent safety profile and minimizes the risk of vitreous hemorrhage by carefully dissecting the vascular adventitial sheath and isolating the embolus. Conclusion: Surgical embolectomy is a viable technique for patients with acute fovea-threatening arterial occlusions without patent cilioretinal artery. Careful dissection and retrieval of the embolus minimizes the risk of vitreous hemorrhage, which is an important improvement in previous techniques for management of acute retinal arterial occlusions. PMID:26674278

  19. Central retinal vein occlusion in a migraine patient.

    PubMed

    Benninger, Felix; Saban, Tal; Steiner, Israel

    2015-11-01

    We describe a 31-year-old woman with a history of migraines without aura, who presented to our emergency department due to a monocular visual disturbance. This was misdiagnosed as being related to her migraine, however, it was subsequently found to be caused by a central retinal vein occlusion. Patients suffering from migraine can experience visual disturbances in the form of auras. The neuropathological basis for this phenomenon is thought to be a spreading depression in the visual cortex, causing a hemifield active visual phenomenon. Missing the diagnosis of central retinal vein occlusion is common, especially in the setting of an initially normal fundoscopy examination.

  20. Clinical Manifestation of Self-Limiting Acute Retinal Necrosis

    PubMed Central

    Brydak-Godowska, Joanna; Borkowski, Piotr; Szczepanik, Szymon; Moneta-Wielgoś, Joanna; Kęcik, Dariusz

    2014-01-01

    Background The purpose of this paper was to present a case series of self-limiting, peripheral acute retinal necrosis and to demonstrate efficacy of treatment with valacyclovir in patients resistant to acyclovir. The diagnosis was made on ophthalmoscopic examination and positive serum tests for herpes viruses. Material/Methods Ten patients (6F and 4M) aged 19–55 years were diagnosed and treated for self-limiting acute retinal necrosis (ARN). The following endpoints were reported: visual outcomes, clinical features, disease progression, treatment, and complications. Patients received only symptomatic treatment because they did not consent to vitreous puncture. Results Peripheral, mild retinitis was diagnosed in all eyes at baseline. Initially, all patients were treated with systemic acyclovir (800 mg, 5 times a day), prednisone (typically 40–60 mg/day), and aspirin in an outpatient setting. In 6 patients, treatment was discontinued at 6 months due to complete resolution of the inflammatory process. Four patients with immune deficiency showed signs and symptoms of chronic inflammation. Two patients did not respond to acyclovir (2 non-responders); however, those patients were successfully treated with valacyclovir. Complete resolution of inflammatory lesions was observed in 8 patients. In 2 patients, the disease progressed despite treatment – 1 female patient after kidney transplant who stopped the prescribed medications, and 1 male patient with SLE and antiphospholipid syndrome who experienced breakthrough symptoms on-treatment. He died due to cerebral venous sinus thrombosis. Neurological complications (encephalitis and meningitis) were observed in 2 female patients. Prophylactic laser photocoagulation was performed in 1 subject. Conclusions A series of cases of self-limiting acute retinal necrosis (ARN) is presented. This clinical form of ARN can resemble toxoplasmic retinitis in some cases. Oral antiviral medications provide an effective alternative to

  1. The role of heredity in determining central retinal thickness

    PubMed Central

    Liew, S H Melissa; Gilbert, Clare E; Spector, Tim D; Marshall, John; Hammond, Christopher J

    2007-01-01

    Aims To examine the relative roles of genetic and environmental factors in central retinal thickness, by performing a classical twin study. Methods 310 subjects were recruited from the TwinsUK adult registry at St Thomas' Hospital. Optical coherence tomography (Zeiss, stratus OCT3) was used to measure the average retinal thickness in the central 1 mm diameter area. The covariance of central retinal thickness (CRT), within MZ and DZ twin pairs, was compared and genetic modelling techniques were used to determine the relative contributions of genes and environment to the variation in CRT observed in this population. Main outcome measure CRT (average retinal thickness in the central 1 mm diameter area, centred on the fovea). Results The mean CRT of all subjects was 212.1 μm (range 165–277). CRT was statistically related to refractive error, with increasing myopia associated with a thinner CRT. CRT was more highly correlated within MZ twin pairs (r = 0.88) than with DZ twin pairs (r = 0.58), suggesting a genetic role. A model combining additive genetic and unique environmental factors provided the best fitting model and gave a heritability estimate of 0.90. Conclusion Genetic factors appear to play an important role in CRT, with a heritability estimate of 0.90. PMID:17360735

  2. RI in central retinal artery as assessed by CDI does not correspond to retinal vascular resistance.

    PubMed

    Polska, E; Kircher, K; Ehrlich, P; Vecsei, P V; Schmetterer, L

    2001-04-01

    The aim of the present study was to investigate the association between ultrasound Doppler measurements of resistive index (RI) in the central retinal artery and retinal vascular resistance (R) assessed with laser Doppler velocimetry, vessel size measurement, and calculation of ocular perfusion pressure (PP) in healthy subjects. An increase in vascular resistance was induced by inhalation of 100% O(2). During hyperoxia no significant changes in PP were observed. Mean flow velocity in main retinal veins was reduced by -27.5 +/- 2.0%. The average decrease in diameter was -11.5 +/- 1.0%. R, which was calculated as the ratio of PP to flow rate, increased by 97.6 +/- 7.7%. RI increased as well, but the effect was much smaller (6.6 +/- 2.2%). In addition, a negative correlation was found between baseline values of R and RI (r = -0.83). During hyperoxia R and RI were not associated. In conclusion, our data indicate that RI as assessed with color Doppler imaging in the central retinal artery is not an adequate measure of R.

  3. Irreversible visual loss and optic nerve dysfunction associated with central retinal vein occlusion in Waldenstrom Macroglobulinemia.

    PubMed

    Fadilah, S A W; Muhaya, M; Azlin, I

    2007-10-01

    Irreversible optic nerve dysfunction associated with central retinal vein occlusion (CRVO) is an unusual but important complication of Waldenstrom Macroglobulinemia (WM). Acute visual loss in CRVO is mainly due the severe macular oedema. However, ischaemic optic neuropathy needs to be considered in patients with CRVO when, (i) there is a relative afferent papillary defect and central scotoma, (ii) the visual acuity is not consistent with the retinal pathology, and (iii) the visual defects persisted despite resolution of macular oedema following treatment of the hyperviscosity state. The ischaemic type of CRVO is associated with a poor visual prognosis and the presenting visual acuity has a prognostic role. We report the first description of irreversible unilateral optic nerve damage associated with CRVO in a patient with WM. PMID:18551947

  4. Association of varicella zoster dermatitis with acute retinal necrosis syndrome.

    PubMed

    Browning, D J; Blumenkranz, M S; Culbertson, W W; Clarkson, J D; Tardif, Y; Gourdeau, A; Minturn, J

    1987-06-01

    The authors report seven patients in whom the acute retinal necrosis (ARN) syndrome developed shortly after cutaneous varicella zoster infection. The length of time between the skin infection and ARN varied from 5 days to 3 months. Both eyes were affected in one of seven cases. The ophthalmic branch of cranial nerve V ipsilateral to an affected eye was involved by the zoster dermatitis in only two of the seven cases. The association lends further support to the proposal that herpes zoster virus is a major cause of ARN. A history of recent zoster dermatitis should be sought in patients with ARN.

  5. Acute unilateral vision loss with optic disc oedema in retinitis pigmentosa.

    PubMed

    Patil-Chhablani, Preeti; Tyagi, Mudit; Kekunnaya, Ramesh; Narayanan, Raja

    2015-01-01

    A 36-year-old woman presented with acute vision loss and was found to have disc oedema and retinitis pigmentosa (RP). She presented with a history of acute, painless vision loss in her left eye over a period of 10 days. Her best-corrected visual acuity was 20/50, N6 in the right eye (OD) and 20/160, N6 in the left eye (OS). She was found to have a swollen optic disc and the examination of her fundus showed changes suggestive of RP. The diagnosis of RP was confirmed by electroretinogram, and after ruling out demyelinating changes in the central nervous system and other possible infectious causes of papillitis, she was treated with intravenous steroids followed by a course of oral steroid therapy. Following treatment, her visual acuity improved to 20/60. Acute vision loss may occur in patients with RP and prompt steroid therapy may result in partial visual recovery. PMID:26240107

  6. Acute unilateral vision loss with optic disc oedema in retinitis pigmentosa.

    PubMed

    Patil-Chhablani, Preeti; Tyagi, Mudit; Kekunnaya, Ramesh; Narayanan, Raja

    2015-01-01

    A 36-year-old woman presented with acute vision loss and was found to have disc oedema and retinitis pigmentosa (RP). She presented with a history of acute, painless vision loss in her left eye over a period of 10 days. Her best-corrected visual acuity was 20/50, N6 in the right eye (OD) and 20/160, N6 in the left eye (OS). She was found to have a swollen optic disc and the examination of her fundus showed changes suggestive of RP. The diagnosis of RP was confirmed by electroretinogram, and after ruling out demyelinating changes in the central nervous system and other possible infectious causes of papillitis, she was treated with intravenous steroids followed by a course of oral steroid therapy. Following treatment, her visual acuity improved to 20/60. Acute vision loss may occur in patients with RP and prompt steroid therapy may result in partial visual recovery.

  7. Ocular neovascularization in eyes with a central retinal artery occlusion or a branch retinal artery occlusion

    PubMed Central

    Mason, John O; Patel, Shyam A; Feist, Richard M; Albert, Michael A; Huisingh, Carrie; McGwin, Gerald; Thomley, Martin L

    2015-01-01

    Purpose To investigate the ocular neovascularization (ONV) rate in eyes with a branch retinal artery occlusion (BRAO) or a central retinal artery occlusion (CRAO), and to study factors that may influence the ONV rate secondary to CRAO. Methods This was a retrospective case series of consecutive patients (286 total eyes: 83 CRAOs and 203 BRAOs) who were diagnosed with a retinal artery occlusion from 1998 to 2013 at the Retina Consultants of Alabama and University of Alabama at Birmingham, Birmingham, AL, USA. Generalized estimating equations were used to evaluate the association between hypothesized risk factors and ONV development. Results Twelve (14.5%) of the 83 eyes with a CRAO developed ONV. Eleven of 12 eyes (91.7%) had iris neovascularization, ten of 12 eyes (83.3%) had neovascular glaucoma, and two of 12 eyes (16.7%) had neovascularization of the optic disc. The average time for ONV development secondary to CRAO was 30.7 days, ranging from the date of presentation to 137 days. Only two (<1.0%) of the 203 eyes with a BRAO developed iris neovascularization. Diabetes mellitus type 2 was a risk factor for ONV development following a CRAO with an adjusted odds ratio of 5.2 (95% confidence interval: 1.4–19.8) (P=0.02). Conclusion ONV is an important complication of CRAO and is a less-frequent complication of BRAO. Patients with a CRAO, especially those with diabetes mellitus type 2, should be closely monitored for the first 6 months for ONV. PMID:26089631

  8. Antiviral selection in the management of acute retinal necrosis

    PubMed Central

    Tam, Patrick MK; Hooper, Claire Y; Lightman, Susan

    2010-01-01

    There is no consensus on the optimal antiviral regimen in the management of acute retinal necrosis, a disease caused by herpetic viruses with devastating consequences for the eye. The current gold standard is based on retrospective case series. Because the incidence of disease is low, few well-designed, randomized trials have evaluated treatment dosage and duration. Newer oral antiviral agents are emerging as alternatives to high-dose intravenous acyclovir, avoiding the need for inpatient intravenous treatment. Drug resistance is uncommon but may also be difficult to identify. Antiviral drugs have few side effects, but special attention needs to be paid to patients who have underlying renal disease, are pregnant or are immunocompromised. PMID:20169044

  9. Recurrent transient monocular blindness from stenotic central retinal artery.

    PubMed

    Choi, Seo Young; Moon, Hye-Jin; Huh, Young-Eun; Yang, Hee Kyung; Woo, Se Joon; Jung, Cheolkyu; Kwon, O-Ki; Kim, Ji-Soo

    2013-11-01

    Transient monocular blindness (TMB) is caused by a temporary reduction of blood flow to the retina or optic nerve. Even though embolism from the ipsilateral carotid artery has been considered the main mechanism of TMB, the vascular pathology remains unknown in many patients. A 42-year-old man presented with recurrent transient visual loss in the left eye for 2 months. The attacks tended to develop more frequently when his head was bent down. Fluorescence angiography during an attack revealed hypoperfusion of the left central retinal artery (CRA) and cerebral angiography documented a focal isolated stenosis of the CRA at the origin. Aspirin and nimodipine reduced the attacks markedly. Stenosis of the CRA may be a cause of TMB. Intermittent vasospasm in addition to static hypoperfusion may have caused TMB in our patient with isolated CRA stenosis.

  10. Retinal Electrophysiology Is a Viable Preclinical Biomarker for Drug Penetrance into the Central Nervous System

    PubMed Central

    Charng, Jason; He, Zheng; Vingrys, Algis J.; Fish, Rebecca L.; Gurrell, Rachel; Bui, Bang V.; Nguyen, Christine T.

    2016-01-01

    Objective. To examine whether retinal electrophysiology is a useful surrogate marker of drug penetrance into the central nervous system (CNS). Materials and Methods. Brain and retinal electrophysiology were assessed with full-field visually evoked potentials and electroretinograms in conscious and anaesthetised rats following systemic or local administrations of centrally penetrant (muscimol) or nonpenetrant (isoguvacine) compounds. Results. Local injections into the eye/brain bypassed the blood neural barriers and produced changes in retinal/brain responses for both drugs. In conscious animals, systemic administration of muscimol resulted in retinal and brain biopotential changes, whereas systemic delivery of isoguvacine did not. General anaesthesia confounded these outcomes. Conclusions. Retinal electrophysiology, when recorded in conscious animals, shows promise as a viable biomarker of drug penetration into the CNS. In contrast, when conducted under anaesthetised conditions confounds can be induced in both cortical and retinal electrophysiological recordings. PMID:27239335

  11. Chloride currents in acutely isolated Xenopus retinal pigment epithelial cells

    PubMed Central

    Hartzell, H Criss; Qu, Zhiqiang

    2003-01-01

    The retinal pigment epithelium (RPE) regulates the ionic composition of the fluid surrounding the photoreceptors by transport mechanisms that utilize Cl− channels. Cl− currents in RPE cells, however, remain incompletely characterized. The purpose of this study was to identify the Cl− currents in acutely isolated Xenopus RPE cells using whole-cell patch clamp. We describe three different Cl− currents. (1) An inwardly rectifying Cl− current, ICl,ir, activates slowly with hyperpolarization (τact=μ1 s at −80 mV, V1/2=−94 ± 3 mV), is blocked by Zn2+ (IC50=185 μm), is stimulated by acid (ICl,ir is 5 times larger at pH 6 than pH 8), and is blocked by DIDS in a voltage-dependent manner. ICl,ir closely resembles cloned ClC-2currents. (2) An outwardly rectifying Cl− current, ICl,Ca, is stimulated by elevated cytosolic free [Ca2+]. With 1 μm free [Ca2+]i in the patch pipette, ICl,Ca activates slowly with depolarization (τact=325 ms at 100 mV) and deactivates upon hyperpolarization. ICl,Ca is not blocked by 1 mm Zn2+ or 10 μm Gd3+ but is blocked by DIDS. High extracellular [Ca2+] (10 mm) also activates ICl,Ca. (3) A non-rectifying current is activated by elevation of cytoplasmic cAMP with forskolin and IBMX. In addition to these three Cl− currents, Xenopus RPE cells exhibit a non-selective background current (Ibkg) which has a linear I-V relationship and is voltage insensitive. This current is blocked by Zn2+ (IC50 of 5.3 μm) or 10 μm Gd3+. This description provides new insights into the physiology of Cl− channels involved in salt and fluid transport by the retinal pigment epithelium. PMID:12665603

  12. Multimodal imaging of central retinal artery occlusion with retained cilioretinal perfusion.

    PubMed

    Walkden, Andrew; Kelly, Simon P

    2016-01-01

    A man aged 59 years old presented with sudden, painless, monocular visual loss due to central retinal artery occlusion. Central vision was retained and peripheral vision lost due to retained cilioretinal perfusion. Increased inner retinal thickening and reflectivity followed by subsequent reduction was documented by sequential imaging. This is the first report of such events monitored with spectral-domain optical coherence tomography where central visual acuity was maintained. PMID:27530879

  13. Central retinal vein occlusion: modifying current treatment protocols.

    PubMed

    Ashraf, M; Souka, A A R; Singh, R P

    2016-04-01

    Central retinal vein occlusion (CRVO) is a common retinal vascular disorder that can result in severe visual acuity loss. The randomized control study, CRUISE, helped establish anti-VEGFs as the standard of care in cases with CRVO. The extension studies for CRUISE; HORIZON and RETAIN showed that not all visual gains are maintained beyond the first year. In addition, patients showed different behavior patterns; with some patients showing complete response with few recurrences, whereas others showed partial or even no response with multiple recurrences. Long-term follow-up demonstrated that patients responding poorly to anti-VEGFs tended to do so early in the course of treatment. It also demonstrated the effectiveness of a pro re nata (PRN) protocol for improving vision and maintaining these gains over long-term follow-ups. The SHORE study further illustrated this point by demonstrating that there were minimal differences in visual outcomes between patients receiving monthly injections and patients being treated PRN. In this review we analyzed the data from the major randomized clinical trials (RCT) that looked at anti-VEGFs as the primary treatment modality in patients with CRVO (CRUISE and the extension studies HORIZON and RETAIN for ranibizumab as well as GALILEO and COPERNICUS for aflibercept). In addition, we looked at SCORE and GENEVA to help determine whether there is a place for steroids as a first line therapy in current treatment practice. We then explored alternative treatment regimens such as laser therapy and switching between anti-VEGF agents and/or steroids for non or partially responding patients. Finally, we propose a simplified modified treatment algorithm for patients with CRVO for better long-term outcomes in all types of responders. PMID:26869163

  14. Association between retinal hemorrhagic pattern and macular perfusion status in eyes with acute branch retinal vein occlusion

    PubMed Central

    Muraoka, Yuki; Uji, Akihito; Tsujikawa, Akitaka; Murakami, Tomoaki; Ooto, Sotaro; Suzuma, Kiyoshi; Takahashi, Ayako; Iida, Yuto; Miwa, Yuko; Hata, Masayuki; Yoshimura, Nagahisa

    2016-01-01

    This prospective study included 63 eyes with acute branch retinal vein occlusion (BRVO) to evaluate the retinal hemorrhagic patterns at the posterior poles and explore their clinical relevance in macular perfusion differentiation. Retinal hemorrhagic patterns and macular perfusion status were evaluated via fundus photography and fluorescein angiography, respectively. Macular perfusion was judged as nonischemic in 30, ischemic in 28, and undeterminable in 5 among the 63 eyes. Predominant hemorrhagic patterns were flame-shaped in 39 (67.2%) and non-flame-shaped in 19 (32.8%) eyes. All 39 eyes with a flame-shaped hemorrhage showed a nonischemic macula. Of the 19 eyes classified as having a non-flame-shaped hemorrhage, 13 (68.4%) had an ischemic macula and 6 (31.6%) had a nonischemic macula (P < 0.001). Parallelism in eyes with a flame-shaped hemorrhage was higher than in those with a non-flame-shaped hemorrhage (P < 0.001), and in those with a nonischemic macula versus those with an ischemic macula (P < 0.001). The area under the curve for parallelism was 0.975 (P < 0.001), suggesting an accurate diagnostic parameter for macular perfusion differentiation. In conclusion, we objectively evaluated retinal hemorrhagic patterns at the posterior pole in BRVO using the parallelism method, which was useful in differentiating macular perfusion status. PMID:27334338

  15. Acute and Chronic Hyperglycemia Elicit JIP1/JNK-Mediated Endothelial Vasodilator Dysfunction of Retinal Arterioles

    PubMed Central

    Hein, Travis W.; Xu, Wenjuan; Xu, Xin; Kuo, Lih

    2016-01-01

    Purpose Hyperglycemia, a hallmark of diabetes mellitus, is associated with retinal inflammation and impairment of endothelium-dependent nitric oxide (NO)–mediated dilation of retinal arterioles. However, molecular mechanisms involved in this diminished endothelial vasodilator function remain unclear. We examined whether inflammatory stress-activated kinases, c-Jun N-terminal kinase (JNK) and p38, contribute to retinal arteriolar dysfunction during exposure to acute and chronic hyperglycemia. Methods Retinal arterioles were isolated from streptozocin-induced diabetic pigs (2 weeks; chronic hyperglycemia, 471 ± 23 mg/dL) or age-matched control pigs (euglycemia, 79 ± 5 mg/dL), and then cannulated and pressurized for vasoreactivity study. For acute hyperglycemia study, vessels from nondiabetic pigs were exposed intraluminally to high glucose (25 mM ≈ 450 mg/dL) for 2 hours, and normal glucose (5 mM ≈ 90 mg/dL) served as the control. Results Endothelium-dependent vasodilation to bradykinin was reduced in a similar manner after exposure to acute or chronic hyperglycemia. Administration of NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) nearly abolished vasodilations either in control (euglycemia and normal glucose) or hyperglycemic (acute and chronic) vessels. Treatment of either acute or chronic hyperglycemic vessels with JNK inhibitor SP600125 or JNK-interacting protein-1 (JIP1) inhibitor BI-78D3, but not p38 inhibitor SB203580, preserved bradykinin-induced dilation in an L-NAME–sensitive manner. By contrast, endothelium-independent vasodilation to sodium nitroprusside was unaffected by acute or chronic hyperglycemia. Conclusions Activation of JIP1/JNK signaling in retinal arterioles during exposure to acute or chronic hyperglycemia leads to selective impairment of endothelium-dependent NO-mediated dilation. Therapeutic targeting of the vascular JNK pathway may improve retinal endothelial vasodilator function during early diabetes. PMID

  16. Unusual presentation of a multiple sclerosis case involving central retinal artery occlusion

    PubMed Central

    Galvez-Ruiz, Alberto; R. Nowilaty, Sawsan

    2014-01-01

    The term intermediate uveitis (IU) refers to a subgroup of uveitis in which the vitreous is the site of greatest inflammation. Patients with multiple sclerosis (MS) have a greater frequency of IU compared with the general population. The IU associated with MS is characterized by the presence of pars planitis (occasionally accompanied by anterior uveitis) and the presence of peripheral retinal vasculitis in the form of periphlebitis (venous sheathing) in 6–26% of patients. We present a patient with an unusual initial presentation of MS involving central retinal artery occlusion (CRAO) in the right eye (RE). Although retinal vascular changes are asymptomatic in the majority of MS patients, the spectrum of impairment ranges from simple peripheral retina periphlebitis to the presence of peripheral occlusive retinal vasculitis in 6.5% of patients. This atypical case may represent an extreme of the spectrum of retinal vasculitis associated with demyelinating disease. PMID:25892937

  17. Protection of Retinal Ganglion Cells and Retinal Vasculature by Lycium Barbarum Polysaccharides in a Mouse Model of Acute Ocular Hypertension

    PubMed Central

    Mi, Xue-Song; Feng, Qian; Lo, Amy Cheuk Yin; Chang, Raymond Chuen-Chung; Lin, Bin; Chung, Sookja Kim; So, Kwok-Fai

    2012-01-01

    Acute ocular hypertension (AOH) is a condition found in acute glaucoma. The purpose of this study is to investigate the protective effect of Lycium barbarum polysaccharides (LBP) and its protective mechanisms in the AOH insult. LBP has been shown to exhibit neuroprotective effect in the chronic ocular hypertension (COH) experiments. AOH mouse model was induced in unilateral eye for one hour by introducing 90 mmHg ocular pressure. The animal was fed with LBP solution (1 mg/kg) or vehicle daily from 7 days before the AOH insult till sacrifice at either day 4 or day 7 post insult. The neuroprotective effects of LBP on retinal ganglion cells (RGCs) and blood-retinal-barrier (BRB) were evaluated. In control AOH retina, loss of RGCs, thinning of IRL thickness, increased IgG leakage, broken tight junctions, and decreased density of retinal blood vessels were observed. However, in LBP-treated AOH retina, there was less loss of RGCs with thinning of IRL thickness, IgG leakage, more continued structure of tight junctions associated with higher level of occludin protein and the recovery of the blood vessel density when compared with vehicle-treated AOH retina. Moreover, we found that LBP provides neuroprotection by down-regulating RAGE, ET-1, Aβ and AGE in the retina, as well as their related signaling pathways, which was related to inhibiting vascular damages and the neuronal degeneration in AOH insults. The present study suggests that LBP could prevent damage to RGCs from AOH-induced ischemic injury; furthermore, through its effects on blood vessel protection, LBP would also be a potential treatment for vascular-related retinopathy. PMID:23094016

  18. An Acute Retinal Model for Evaluating Blood Retinal Barrier Breach and Potential Drugs for Treatment.

    PubMed

    Wu, Hao; Rodriguez, Ana R; Spur, Bernd W; Venkataraman, Venkat

    2016-01-01

    A low-cost, easy-to-use and powerful model system is established to evaluate potential treatments that could ameliorate blood retinal barrier breach. An inflammatory factor, histamine, is demonstrated to compromise vessel integrity in the cultured retina through positive staining of IgG outside of the blood vessels. The effects of histamine itself and those of candidate drugs for potential treatments, such as lipoxin A4, are assessed using three parameters: blood vessel leakage via IgG immunostaining, activation of Müller cells via GFAP staining and change in neuronal dendrites through staining for MAP2. Furthermore, the layered organization of the retina allows a detailed analysis of the processes of Müller and ganglion cells, such as changes in width and continuity. While the data presented is with swine retinal culture, the system is applicable to multiple species. Thus, the model provides a reliable tool to investigate the early effects of compromised retinal vessel integrity on different cell types and also to evaluate potential drug candidates for treatment. PMID:27684428

  19. Unilateral sequential papillophlebitis and central retinal artery occlusion in a young healthy patient

    PubMed Central

    Demirok, Gülizar; Kocamaz, Mehmet Fatih; Topalak, Yasemin; Şengün, Ahmet; Hasanreisoğlu, Berati

    2015-01-01

    A 23-year-old girl presented to the clinic with metamorphopsia and photopsia in her left eye. After detailed ophthalmic examination, central retinal vein occlusion with optic disc edema was detected in that eye. Three days after diagnosis, the patient returned to our clinic with visual acuity decrease. Central retinal artery occlusion sparing cilioretinal artery was detected. All the laboratory tests were normal except for heterozygous methylenetetrahydrofolate reductase mutation (A1298C genotypes) and an indefinite Lyme disease seropositivity. Symptoms and visual disturbance recovered without any further treatment other than acetylsalicylic acid for prophylaxis. PMID:26862099

  20. A prospective case-control study to investigate retinal microvascular changes in acute dengue infection.

    PubMed

    Tan, Petrina; Lye, David C; Yeo, Tun Kuan; Cheung, Carol Y; Thein, Tun-Linn; Wong, Joshua G; Agrawal, Rupesh; Li, Ling-Jun; Wong, Tien-Yin; Gan, Victor C; Leo, Yee-Sin; Teoh, Stephen C

    2015-01-01

    Dengue infection can affect the microcirculation by direct viral infection or activation of inflammation. We aimed to determine whether measured retinal vascular parameters were associated with acute dengue infection. Patients with acute dengue were recruited from Communicable Diseases Center, Singapore and age-gender-ethnicity matched healthy controls were selected from a population-based study. Retinal photographs were taken on recruitment and convalescence. A spectrum of quantitative retinal microvascular parameters (retinal vascular caliber, fractal dimension, tortuosity and branching angle) was measured using a semi-automated computer-based program. (Singapore I Vessel Assessment, version 3.0). We included 62 dengue patients and 127 controls. Dengue cases were more likely to have wider retinal arteriolar and venular calibers (158.3 μm vs 144.3 μm, p < 0.001; 227.7 μm vs 212.8 μm, p < 0.001; respectively), higher arteriolar and venular fractal dimensions (1.271 vs 1.249, p = 0.002; 1.268 vs. 1.230, p < 0.001, respectively), higher arteriolar and venular tortuosity (0.730 vs 0.546 [x10(4)], p < 0.001; 0.849 vs 0.658 [x10(4)], p < 0.001; respectively), compared to controls. Resolution of acute dengue coincided with decrease in retinal vascular calibers and venular fractal dimension. Dengue patients have altered microvascular network in the retina; these changes may reflect pathophysiological processes in the immune system.

  1. Concomitant multiple myeloma spectrum diagnosis in a central retinal vein occlusion: a case report and review.

    PubMed

    Borgman, Christopher J

    2016-07-01

    Multiple myeloma is a neoplastic plasma-cell disorder resulting from malignant plasma cells in the bone marrow. It can cause a hyperviscosity syndrome secondary to the paraproteinaemia associated with the disease. The increased hyperviscosity can lead to retinal vein occlusions and other ocular problems that may challenge clinicians. In patients with multiple myeloma and hypertension and/or diabetes mellitus, retinal changes appear similar and changes due to one disease or the other may be difficult to determine. A 48-year-old white female presented to the clinic with a complaint of blurry vision in her left eye. A full comprehensive ocular examination revealed a central retinal vein occlusion presumably from the patient's history of hypertension, diabetes mellitus and hypercholesterolaemia. Further bloodwork revealed monoclonal protein in the patient's serum and an increased percentage of plasma cells in the bone marrow. She was diagnosed with monoclonal gammopathy of undetermined significance, part of the multiple myeloma disease spectrum. She was referred to a retinal specialist for initiation of intravitreal injections of anti-vascular endothelial growth factor. Multiple myeloma has been implicated in younger patients as an underlying cause of retinal vein occlusions. Multiple myeloma should be considered as a differential diagnosis in young patients with retinal vein occlusions, even if other risk factors for venous occlusion like hypertension, diabetes mellitus and hypercholesterolaemia are present. Timely referral to the patient's primary care physician and haematologist is important for appropriate treatment and control of underlying systemic conditions. PMID:27079282

  2. Nonmydriatic retinal photography in the evaluation of acute neurologic conditions

    PubMed Central

    Bidot, Samuel; Bruce, Beau B.; Newman, Nancy J.; Biousse, Valérie

    2013-01-01

    Summary Ocular fundus examination is a fundamental component of the neurologic examination. Finding papilledema in headache patients or retinal arterial emboli in stroke patients can be extremely useful. Although examination of the ocular fundus with a direct ophthalmoscope is an important skill for all neurologists, it is rarely and unreliably performed. Nonmydriatic ocular fundus photography, which allows direct visualization of high-quality photographs of the ocular fundus, has been recently proposed for screening neurologic patients in urgent care settings such as emergency departments. This new technology has many potential applications in neurology, including e-transmission of images for remote interpretation. PMID:24353924

  3. Activated protein C resistance in patients with central retinal vein occlusion

    PubMed Central

    Larsson, J; Sellman, A; Bauer, B

    1997-01-01

    AIM/BACKGROUND—A new defect in the anticoagulant system has recently been discovered—activated protein C resistance. The frequency of this disorder has been shown to be increased in young patients (<50 years of age) with central retinal vein occlusion. This study was carried out to determine if there was any overrepresentation of activated protein C resistance in patients >50 years of age with central retinal vein occlusion.
METHODS—Blood samples were obtained from 83 patients >50 years of age and with a history of central retinal vein occlusion. The blood samples were analysed for activated protein C resistance with standard clinical laboratory methods.
RESULTS—In this material 11% of the patients were resistant to activated protein C. The normal incidence of activated protein C resistance in the same geographical area is 10-11%.
CONCLUSION—Activated protein C resistance does not seem to be a cause of central retinal vein occlusion in people older than 50 years.

 PMID:9486021

  4. N-acetylcysteine and acute retinal laser lesions in the colubrid snake eye

    NASA Astrophysics Data System (ADS)

    Elliott, William R., III; Rentmeister-Bryant, Heike K.; Barsalou, Norman; Beer, Jeremy; Zwick, Harry

    2004-07-01

    This study examined the role of oxidative stress and the effect of a single dose treatment with N-Acetylcysteine (NAC) on the temporal development of acute laser-induced retinal injury. We used the snake eye/Scanning Laser Ophthalmoscope (SLO) model, an in vivo, non-invasive ocular imaging technique, which has the ability to image cellular retinal detail and allows for studying morphological changes of retinal injury over time. For this study 12 corn-snakes (Elaphe g. guttata) received 5 laser exposures per eye, followed by either a single dose of the antioxidant NAC (150mg/kg, IP in sterile saline) or placebo. Laser exposures were made with a Nd: VO4 DPSS, 532nm laser, coaxially aligned to the SLO. Shuttered pulses were 20msec x 50 mW; 1mJ each. Retinal images were taken using a Rodenstock cSLO and were digitally recorded at 1, 6, 24-hrs, and at 3-wks post-exposure. Lesions were assessed by two raters blind to the conditions of the study yielding measures of damaged area and counts of missing or damaged photoreceptors. Treated eyes showed a significant beneficial effect overall, and these results suggest that oxidative stress plays a role in laser-induced retinal injury. The use of NAC or a similar antioxidant shows promise as a therapeutic tool.

  5. Aortic stiffness is associated with the central retinal arteriolar equivalent and retinal vascular fractal dimension in a population along the southeastern coast of China.

    PubMed

    Lin, Fan; Zhu, Pengli; Huang, Feng; Li, Qiaowei; Yuan, Yin; Gao, Zhonghai; Yu, Peng; Lin, Jing; Chen, Falin

    2015-05-01

    The objective of this study was to evaluate the association of the central retinal arteriolar equivalent (CRAE) and the retinal vascular fractal dimension, two quantitative parameters that reflect microcirculation, with aortic stiffness. In this cross-sectional study, we identified the cardiovascular risk factors in 2169 subjects using a health questionnaire, physical examinations and laboratory examinations. We evaluated the aortic stiffness using noninvasive brachial-ankle pulse wave velocity (baPWV) and assessed the microcirculatory alterations with CRAE and retinal vascular fractal dimension, which were measured using fundus photography and semiautomatic quantitative software, respectively. The increase in baPWV (Q1-Q4) correlated with an increased likelihood of the central retinal artery narrowing and a reduction in the retinal vascular fractal dimension. Further adjustment of the cardiovascular risk factors diminished the association between baPWV and CRAE, but increased the association between baPWV and retinal vascular fractal dimension. Elevated baPWV correlates with reduced CRAE and retinal vascular fractal dimension. Such a finding supports macrocirculation- and microcirculation-associated hypotheses.

  6. Good visual outcome in an immunocompromised patient with bilateral acute retinal necrosis syndrome: A case report

    PubMed Central

    Marrocos de Aragão, Ricardo E.; Barreira, Ieda M.A.; Arrais, Barbara L.A.; Pereira, Leidiane A.; Ramos, Carine S.

    2013-01-01

    Acute retinal necrosis (ARN) is an uncommon necrotizing, fulminant retinopathy caused by the herpes simplex virus types 1 or 2 or by the varicella zoster vírus with visually devastating consequences. Generally it occurs in patients who are systemically healthy, but occasionally occurs in immunocompromised host. We report a case of bilateral ARN in a patient with AIDS with a good final visual outcome. PMID:25278806

  7. [The pulsation and the pressure of the central retinal vein and their relation to glaucoma damage and therapy].

    PubMed

    Stodtmeister, R

    2008-07-01

    Until now the pressure in the intraocular veins was generally equated with the intraocular pressure. According to recently available knowledge the pressure in the central retinal vein may be considerably higher than the intraocular pressure. Therefore, the pressure in the veins of the prelaminar layer of the optic nerve head may be higher than the intraocular pressure also. In this case the perfusion pressure equals the difference: arterial pressure minus central retinal venous pressure. It has been shown that the central retinal venous pressure is higher in glaucoma patients than in healthy subjects and it is higher in the eyes with the larger excavation in patients with unequal excavations. The central retinal venous pressure is a considerable risk factor for the progression of glaucoma damage. It seems to be appropriate to judge the pulsation of the central retinal vein in glaucoma patients, assessing the risk of glaucoma damage, and to measure the pressure in the central retinal vein by contact lens dynamometry. It may be concluded that a solely pressure-lowering therapy is ineffective in eyes in which the pressure of the central retinal vein is higher than the intraocular pressure. That may apply to about 40-50% of glaucoma patients.

  8. Acute Retinal Necrosis Associated with Epstein-Barr Virus in a Patient Undergoing Immunosuppressive Therapy

    PubMed Central

    Oe, Chiaki; Hiraoka, Miki; Tanaka, Sachie; Ohguro, Hiroshi

    2016-01-01

    Acute retinal necrosis (ARN) is a rapidly progressive and severe retinitis resulting in a poor visual outcome. Infections caused by herpes viruses such as herpes simplex virus (HSV) types 1 and 2 or the varicella zoster virus (VZV) are known to be implicated in the development of ARN. In the present study, an 80-year-old female with ARN was examined. She had been affected with rheumatoid arthritis and had taken methotrexate for over 10 years. Her right eye showed clinical features of ARN, and her left eye showed mild retinitis. The genomic DNA in the aqueous humor and vitreous fluid from her right eye were analyzed by a comprehensive polymerase chain reaction (PCR) assay to screen infectious pathogens including viruses. The Epstein-Barr virus (EBV) was detected from both specimens, but neither HSV or VZV nor cytomegalovirus was detected. She underwent intraocular surgery following systemic corticosteroid and acyclovir applications. However, although the retinitis of her right eye was extinguished, the final visual outcome was blindness due to optic nerve atrophy. There are few reports indicating that EBV is associated with ARN development. The present findings suggest that EBV alone can be the causative agent of ARN. PMID:27194989

  9. Acute Retinal Necrosis Associated with Epstein-Barr Virus in a Patient Undergoing Immunosuppressive Therapy.

    PubMed

    Oe, Chiaki; Hiraoka, Miki; Tanaka, Sachie; Ohguro, Hiroshi

    2016-01-01

    Acute retinal necrosis (ARN) is a rapidly progressive and severe retinitis resulting in a poor visual outcome. Infections caused by herpes viruses such as herpes simplex virus (HSV) types 1 and 2 or the varicella zoster virus (VZV) are known to be implicated in the development of ARN. In the present study, an 80-year-old female with ARN was examined. She had been affected with rheumatoid arthritis and had taken methotrexate for over 10 years. Her right eye showed clinical features of ARN, and her left eye showed mild retinitis. The genomic DNA in the aqueous humor and vitreous fluid from her right eye were analyzed by a comprehensive polymerase chain reaction (PCR) assay to screen infectious pathogens including viruses. The Epstein-Barr virus (EBV) was detected from both specimens, but neither HSV or VZV nor cytomegalovirus was detected. She underwent intraocular surgery following systemic corticosteroid and acyclovir applications. However, although the retinitis of her right eye was extinguished, the final visual outcome was blindness due to optic nerve atrophy. There are few reports indicating that EBV is associated with ARN development. The present findings suggest that EBV alone can be the causative agent of ARN.

  10. Central projections of intrinsically photosensitive retinal ganglion cells in the macaque monkey

    PubMed Central

    Hannibal, J.; Kankipati, L.; Strang, C.E.; Peterson, B.B.; Dacey, D.; Gamlin, P.D.

    2014-01-01

    Circadian rhythms generated by the suprachiasmatic nucleus (SCN) are entrained to the environmental light/dark cycle via intrinsically photosensitive retinal ganglion cells (ipRGCs) expressing the photopigment melanopsin and the neuropeptide PACAP. The ipRGCs regulate other non-image-forming visual functions such as the pupillary light reflex, masking behaviour and light induced melatonin suppression. To evaluate whether PACAP immunoreactive retinal projections are useful as a marker for central projection of ipRGCs in the monkey brain, we characterized the occurrence of PACAP in melanopsin expressing ipRGCs and in the retinal target areas in the brain visualized by the anterograde tracer Cholera Toxin subunit B (CtB) in combination with PACAP staining. In the retina, PACAP and melanopsin were found to be co-stored in 99% of melanopsin expressing cells characterized as inner and outer stratifying melanopsin RGCs. Two macaque monkeys were anesthetized and received a unilateral intravitreal injection of CtB. Bilateral retinal projections containing co-localized CtB and PACAP immunostaining were identified in the SCN, the lateral geniculate complex (LGN) including the pregeniculate nucleus (PrGC), the pretectal olivary nucleus (PON), the nucleus of the optic tract (NOT), the brachium of the superior colliculus (BSC), and the superior colliculus (SC). In conclusion, PACAP immunoreactive projections with co-localized CtB represent retinal projections of ipRGCs in the macaque monkey, and support previous retrograde tracer studies demonstrating that melanopsin containing retinal projections reach areas in the primate brain involved in both image and non-image-forming visual processing. PMID:24752373

  11. Evidence for an enduring ischaemic penumbra following central retinal artery occlusion, with implications for fibrinolytic therapy.

    PubMed

    McLeod, David; Beatty, Stephen

    2015-11-01

    The rationale behind hyperacute fibrinolytic therapy for cerebral and retinal arterial occlusion is to rescue ischaemic cells from irreversible damage through timely restitution of tissue perfusion. In cerebral stroke, an anoxic tissue compartment (the "infarct core") is surrounded by a hypoxic compartment (the "ischaemic penumbra"). The latter comprises electrically-silent neurons that undergo delayed apoptotic cell death within 1-6 h unless salvaged by arterial recanalisation. Establishment of an equivalent hypoxic compartment within the inner retina following central retinal artery occlusion (CRAO) isn't widely acknowledged. During experimental CRAO, electroretinography reveals 3 oxygenation-based tissue compartments (anoxic, hypoxic and normoxic) that contribute 32%, 27% and 41% respectively to the pre-occlusion b-wave amplitude. Thus, once the anoxia survival time (≈2 h) expires, the contribution from the infarcted posterior retina is irreversibly extinguished, but electrical activity continues in the normoxic periphery. Inbetween these compartments, an annular hypoxic zone (the "penumbra obscura") endures in a structurally-intact but functionally-impaired state until retinal reperfusion allows rapid recovery from electrical silence. Clinically, residual circulation of sufficient volume flow rate generates the heterogeneous fundus picture of "partial" CRAO. Persistent retinal venous hypoxaemia signifies maximal extraction of oxygen by an enduring "polar penumbra" that permeates or largely replaces the infarct core. On retinal reperfusion some days later, the retinal venous oxygen saturation reverts to normal and vision improves. Thus, penumbral inner retina, marginally oxygenated by the choroid or by residual circulation, isn't at risk of delayed apoptotic infarction (unlike hypoxic cerebral cortex). Emergency fibrinolytic intervention is inappropriate, therefore, once the duration of CRAO exceeds 2 h. PMID:26113210

  12. Evidence for an enduring ischaemic penumbra following central retinal artery occlusion, with implications for fibrinolytic therapy.

    PubMed

    McLeod, David; Beatty, Stephen

    2015-11-01

    The rationale behind hyperacute fibrinolytic therapy for cerebral and retinal arterial occlusion is to rescue ischaemic cells from irreversible damage through timely restitution of tissue perfusion. In cerebral stroke, an anoxic tissue compartment (the "infarct core") is surrounded by a hypoxic compartment (the "ischaemic penumbra"). The latter comprises electrically-silent neurons that undergo delayed apoptotic cell death within 1-6 h unless salvaged by arterial recanalisation. Establishment of an equivalent hypoxic compartment within the inner retina following central retinal artery occlusion (CRAO) isn't widely acknowledged. During experimental CRAO, electroretinography reveals 3 oxygenation-based tissue compartments (anoxic, hypoxic and normoxic) that contribute 32%, 27% and 41% respectively to the pre-occlusion b-wave amplitude. Thus, once the anoxia survival time (≈2 h) expires, the contribution from the infarcted posterior retina is irreversibly extinguished, but electrical activity continues in the normoxic periphery. Inbetween these compartments, an annular hypoxic zone (the "penumbra obscura") endures in a structurally-intact but functionally-impaired state until retinal reperfusion allows rapid recovery from electrical silence. Clinically, residual circulation of sufficient volume flow rate generates the heterogeneous fundus picture of "partial" CRAO. Persistent retinal venous hypoxaemia signifies maximal extraction of oxygen by an enduring "polar penumbra" that permeates or largely replaces the infarct core. On retinal reperfusion some days later, the retinal venous oxygen saturation reverts to normal and vision improves. Thus, penumbral inner retina, marginally oxygenated by the choroid or by residual circulation, isn't at risk of delayed apoptotic infarction (unlike hypoxic cerebral cortex). Emergency fibrinolytic intervention is inappropriate, therefore, once the duration of CRAO exceeds 2 h.

  13. Central retinal artery occlusion as an iatrogenic complication of treatment of central giant cell granuloma of the mandible.

    PubMed

    Bhushan, Gauri; Gupta, Swati; Bhushan, Urvashi; Raina, Usha Kaul

    2015-05-01

    Although intralesional steroid injection as a management option for central giant cell granuloma (CGCG) of the mandible is considered safe, central retinal artery occlusion (CRAO) is a dreaded and previously unreported complication of this treatment modality. The present report discusses an iatrogenic case of CRAO that occurred during treatment of CGCG of the mandible. This complication occurred because of high injection pressure, which led to the opening of an anastomosis between the external and internal carotid arteries, leading to retrograde migration of steroid particles. This report also highlights the importance of being aware of such communications.

  14. Acute central cervical spinal cord syndrome.

    PubMed

    Morse, S D

    1982-08-01

    Two cases of the acute central cervical spinal cord syndrome are presented. A 63-year-old diabetic hypertensive man manifested the syndrome as a result of atraumatic ischemia of the cord. A 32-year-old health man developed it after sustaining a hyperextension injury in a baseball game. The pathogenesis and pathophysiology of this entity are reviewed. Knowledge of this entity is of major importance in the analysis and management of head and neck trauma, as well as in the recognition and management of atraumatic neurologic dysfunction due to ischemia, hemorrhage, or thrombosis.

  15. Fulminant bilateral acute retinal necrosis syndrome associated with viral encephalitis: A case report

    PubMed Central

    Zhou, Chunkui; Zhu, Lijun; Fang, Shaokuan

    2016-01-01

    Herpes simplex virus (HSV) is the most common cause of acute viral encephalitis. Acute retinal necrosis (ARN) is a rapidly progressing and potentially blinding eye disease that may be induced by HSV. The present case study reports the very rare case of a patient with herpes simplex encephalitis (HSE) combined with acute retinal necrosis (ARN). A 47-year-old woman was admitted to hospital with persistent high fever and somnolence for 5 days. Magnetic resonance imaging showed abnormal signals in the right medial temporal lobes, and HSV-1 was identified in the serum and cerebrospinal fluid. Five days later, despite treatment with intravenous acyclovir and partial improvement in consciousness, the patient suddenly developed blurred vision and bilateral visual pain. Fundus fluorescence angiography revealed bilateral vessel obstruction and flaky reduced fluorescence. ARN was diagnosed clinically. Dexamethasone was administered as an anti-inflammatory adjunct to intravenous acyclovir therapy. The visual acuity of the patient was reduced to mere light perception a further 4 days later. The present case indicates that HSE may be complicated with ARN, causing a reduction in visual acuity to mere light perception within a very short time.

  16. Fulminant bilateral acute retinal necrosis syndrome associated with viral encephalitis: A case report

    PubMed Central

    Zhou, Chunkui; Zhu, Lijun; Fang, Shaokuan

    2016-01-01

    Herpes simplex virus (HSV) is the most common cause of acute viral encephalitis. Acute retinal necrosis (ARN) is a rapidly progressing and potentially blinding eye disease that may be induced by HSV. The present case study reports the very rare case of a patient with herpes simplex encephalitis (HSE) combined with acute retinal necrosis (ARN). A 47-year-old woman was admitted to hospital with persistent high fever and somnolence for 5 days. Magnetic resonance imaging showed abnormal signals in the right medial temporal lobes, and HSV-1 was identified in the serum and cerebrospinal fluid. Five days later, despite treatment with intravenous acyclovir and partial improvement in consciousness, the patient suddenly developed blurred vision and bilateral visual pain. Fundus fluorescence angiography revealed bilateral vessel obstruction and flaky reduced fluorescence. ARN was diagnosed clinically. Dexamethasone was administered as an anti-inflammatory adjunct to intravenous acyclovir therapy. The visual acuity of the patient was reduced to mere light perception a further 4 days later. The present case indicates that HSE may be complicated with ARN, causing a reduction in visual acuity to mere light perception within a very short time. PMID:27698716

  17. Visual Improvement after Intra-Arterial Thrombolysis for Central Retinal Artery Occlusion Does Not Correlate with Time to Treatment

    PubMed Central

    Page, Paul S.; Cambon, Alexander C.; James, Robert F.

    2016-01-01

    Background Intra-arterial thrombolysis (IAT) for the treatment of acute central retinal artery occlusion (CRAO) has demonstrated variable results for improving visual acuity and remains controversial. Despite limited evidence, time from symptom onset to thrombolysis is believed to be an important factor in predicting visual improvement after IAT. Methods A comprehensive review of the literature was conducted and individual subject level data were extracted from relevant studies. From these, a secondary analysis was performed. Initial and final logarithm of the minimum angle of resolution (logMAR) scores were either abstracted directly from relevant studies or converted from provided Snellen chart scores. Change in logMAR scores was used to determine overall treatment efficacy. Results Data on 118 patients undergoing IAT from five studies were evaluated. Median logMAR improvement in visual acuity was −0.400 (p < 0.001). There was no significant association between logMAR change and time to treatment when time (hours) was described as a continuous variable or described categorically [0–4, 4–8, 8–12, 12+ h; or 0–6, 6–12, 12+ h]. Conclusion The visual improvement observed in this series had no relationship to the time from symptom onset to treatment with IAT. This suggests that patients may have the possibility for improvement even with delayed presentation to the neurointerventionalist. Other factors, such as completeness of retinal occlusion, may be more important than time to treatment. Additional studies to determine optimal patient selection criteria for the endovascular treatment of acute CRAO are needed.

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

    PubMed

    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

  19. A case of polyarteritis nodosa complicated by left central retinal artery occlusion, ischemic optic neuropathy, and retinal vasculitis.

    PubMed

    Emad, Y; Basaffar, S; Ragab, Y; Zeinhom, F; Gheita, T

    2007-05-01

    A 23-year-old single female patient developed constitutional manifestations in the form of fever, weight loss, anorexia, malaise, fatigue, and generalized aches in January 1995, 2 weeks after an attack of German measles. This was followed by painful, reddish, macular skin lesions over both legs which healed by dark pigmentation (leucocytoclastic vasculitis), mononeuritis multiplex, and Raynaud's phenomena of both hands and feet. Angiography of lower limbs was done to visualize the arterial tree of both lower limbs and revealed typical beading of distal arterial branches, a diagnosis compatible with polyarteritis nodosa (PAN). At that time, the patient received prednisone (45 mg/day) and azatioprin (100 mg/day) and responded well to treatment. In a second presentation in June 2005, the patient developed sudden attack of loss of vision in her left eye. Ophthalmological examination of the patient revealed evidence of left central retinal artery occlusion, ischemic optic neuropathy. The patient received methyl prednisolone, 1 g IV infusion, daily infusion for three consecutive days followed by oral prednisolone, 30 mg/day. The patient received pulse cyclophosphamide IV infusion (0.6 g/m2) on the fourth day. One week after receiving therapy, the patient progressed from having light perception to counting of fingers from a distance of 1 m.

  20. The effect of acute ethanol consumption on the human retinal circulation: a study in diabetic and non-diabetic subjects.

    PubMed

    Dhasmana, D; Herbert, L; Patel, V; Chen, H C; Jones, M; Kohner, E M

    1994-01-01

    The effects of acute ethanol consumption on retinal haemodynamics and retinal vascular autoregulation to oxygen in the human retinal circulation were studied in 10 diabetic (mean age +/- SD: 38.2 +/- 11.1) and 16 non-diabetic (mean age +/- SD: 32.4 +/- 8.8) subjects. Subjects drank 0.5 g of ethanol, as vodka, per kg of body weight, diluted in sugar-free orange juice. Retinal blood flow was determined using laser Doppler velocimetry and computerised image analysis. The effect of ethanol on oxygen reactivity, as a measure of autoregulation, was also determined after 60% oxygen inhalation. All subjects demonstrated a significant fall in mean arterial blood pressure (control group 3.3%, p = 0.04, diabetic subjects 5.7%, p = 0.05), after ethanol intake. Ethanol caused no significant change in retinal blood flow. Oxygen reactivity was found to be 38.3% (22.4-47.7, median and interquartile range) in the non-diabetic subjects at baseline, and 30.7% (10.8-42.1) after ethanol ingestion. In diabetic subjects, the oxygen reactivity was 33.2% (19.8-46.8) at baseline and 24.5% (21.1-32.1) after ethanol. In this study ethanol did not significantly affect retinal blood flow or impair autoregulation. These results suggest that the retinal circulation may be able to autoregulate despite the presence of ethanol, in contrast to other vascular beds where ethanol changes flow. PMID:7819729

  1. Central retinal artery occlusion by proxy: a cause for sudden blindness in an airline passenger.

    PubMed

    Polk, J D; Rugaber, Christopher; Kohn, Gary; Arenstein, Ronald; Fallon, William F

    2002-04-01

    The use of gas media in ophthalmologic procedures is relatively commonplace. Scleral buckle and pneumatic retinopexy procedures using air-gas mediums are a widely accepted treatment for retinal detachment. We present a patient who had a scleral buckle with pneumatic retinopexy performed and subsequently flew in a commercial airliner 2 wk later. The patient experienced sudden blindness due to central retinal artery occlusion brought about by expansion of the air bubble when the aircraft reached cruise altitude and a cabin pressure of 8000 ft. The intraocular pressure exceeded the central artery pressure thereby collapsing the artery. The patient's symptoms were relieved when an onboard flight surgeon identified the problem and the cabin pressure was reset to 2000 ft. Flying after an ophthalmic procedure that incorporates intraocular gas may have complications due to the bubble expansion in accordance with Boyle's Law. The ophthalmologic surgeon must be diligent in forewarning patients of the potential complications of flying for weeks to months after a procedure that utilizes intraocular gas. PMID:11952061

  2. Central Retinal and Posterior Ciliary Artery Occlusion After Intralesional Injection of Sclerosant to Glabellar Subcutaneous Hemangioma

    SciTech Connect

    Matsuo, Toshihiko; Fujiwara, Hiroyasu; Gobara, Hideo; Mimura, Hidefumi; Kanazawa, Susumu

    2009-03-15

    The aim of this study is to describe vision loss caused by central retinal artery and posterior ciliary artery occlusion as a consequence of sclerotherapy with a polidocanol injection to a glabellar hemangioma. An 18-year-old man underwent direct injection with a 23-gauge needle of 1 mL of a polidocanol-carbon dioxide emulsion into the glabellar subcutaneous hemangioma under ultrasound visualization of the needle tip by radiologists. He developed lid swelling the next day, and 3 days later at referral, the visual acuity in the left eye was no light perception. Funduscopy revealed central retinal artery occlusion and fluorescein angiography disclosed no perfusion at all in the left fundus, indicating concurrent posterior ciliary artery occlusion. The patient also showed mydriasis, blepharoptosis, and total external ophthalmoplegia on the left side. Magnetic resonance imaging demonstrated the swollen medial rectus muscle. In a month, blepharoptosis and ophthalmoplegia resolved but the visual acuity remained no light perception. Sclerosing therapy for facial hemangioma may develop a severe complication such as permanent visual loss.

  3. Central retinal artery occlusion by proxy: a cause for sudden blindness in an airline passenger.

    PubMed

    Polk, J D; Rugaber, Christopher; Kohn, Gary; Arenstein, Ronald; Fallon, William F

    2002-04-01

    The use of gas media in ophthalmologic procedures is relatively commonplace. Scleral buckle and pneumatic retinopexy procedures using air-gas mediums are a widely accepted treatment for retinal detachment. We present a patient who had a scleral buckle with pneumatic retinopexy performed and subsequently flew in a commercial airliner 2 wk later. The patient experienced sudden blindness due to central retinal artery occlusion brought about by expansion of the air bubble when the aircraft reached cruise altitude and a cabin pressure of 8000 ft. The intraocular pressure exceeded the central artery pressure thereby collapsing the artery. The patient's symptoms were relieved when an onboard flight surgeon identified the problem and the cabin pressure was reset to 2000 ft. Flying after an ophthalmic procedure that incorporates intraocular gas may have complications due to the bubble expansion in accordance with Boyle's Law. The ophthalmologic surgeon must be diligent in forewarning patients of the potential complications of flying for weeks to months after a procedure that utilizes intraocular gas.

  4. Radial optic neurotomy in treating central retinal vein occlusion: a Meta-analysis

    PubMed Central

    Chen, Zhen-Na; Shao, Yan; Li, Xiao-Rong

    2016-01-01

    AIM To assess the feasibility of radial optic neurotomy (RON) in central retinal vein occlusion (CRVO) treatment with a Meta-analysis. METHODS Electronic databases were searched for comprehensive articles that compared efficacy of RON with that of other treatments in CRVO. Study quality was assessed and risk ratio (RR) and 95% confidence interval (CI) with fix- or random-effects model were calculated according to the heterogeneity. RESULTS A total of 200 eyes from 5 studies were included. The results indicated that no significant differences were found between groups with and without RON in improvement of visual acuity (VA) at 6mo follow-up (pooled RR 0.51, 95%CI 0.22 to 1.18, P=0.117) while improvement of VA showed significantly favourable in patients receiving RON treatment at 12mo follow-up (pooled RR 2.27, 95%CI 1.31 to 3.95, P=0.004). For complications, RON treatment was more effective in reducing neovascular glaucoma (pooled RR 0.45, 95%CI 0.21 to 0.97, P=0.042) but was comparable in retinal detachment (pooled RR 2.41, 95%CI 0.51 to 11.39, P=0.267) and vitreous hemorrhage (pooled RR 0.91, 95%CI 0.33 to 2.46, P=0.847). CONCLUSION Compared with some certain treatment modalities, RON might offer better VA at 12mo and decrease the rate of neovascular glaucoma without changing the rate of retinal detachment and vitreous hemorrhage. Further studies are required considering the limitation of the research. PMID:27366695

  5. Lesions of the mitral valve as a cause of central retinal artery occlusion: presentation and discussion of two cases.

    PubMed

    Ayati, Maryam; Gori, Tommaso; Münzel, Thomas

    2010-01-01

    We present two cases of mitral valve lesions that manifested with unilateral blindness caused by central retinal artery occlusion (CRAO): Case 1. A 68-year-old woman was admitted to our clinic for sudden blindness. Retinal artery angiogram showed CRAO. Transthoracic and transesophageal echocardiography (TEE) documented a mass attached to the ventricular side of the posterior mitral leaflet, which at pathology was identified as a blood cyst. Case 2. A 67-year-old man was admitted for a sudden unilateral painless loss of vision. Retinal angiogram documented CRAO, and TEE showed a highly mobile, spherical, lesion on the atrial side of anterior mitral leaflet. In this case, the pathological finding was a degenerated calcified thrombosis. We report on two cases of very rare abnormalities of the mitral valve presenting with a very rare embolic complication, i.e., CRAO. Like for cryptogenic stroke, transesophageal echocardiography plays a central role in the diagnosis of cardiogenic embolic sources. PMID:20070361

  6. Central Retinal Vein Occlusion: A Review of Current Evidence-based Treatment Options

    PubMed Central

    Patel, Amy; Nguyen, Christine; Lu, Stephanie

    2016-01-01

    A central retinal vein occlusion (CRVO) can induce an ischemic and hypoxic state with resulting sequelae of macular edema and neovascularization. Many treatment options have been studied. Our review aims to investigate the safety and efficacy of the multiple treatment options of CRVO. A PubMed and Cochrane literature search was performed. Well-controlled randomized clinical trials that demonstrated strong level 1 evidence-based on the rating scale developed by the British Centre for Evidence-Based Medicine were included. Seven clinical trials met inclusion criteria to be included in this review. These included studies that investigated the safety and efficacy of retinal photocoagulation (1 study), intravitreal steroid treatment (2 studies), and antivascular endothelial growth factor treatment (4 studies) for the treatment of CRVO. In addition, studies evaluating surgical treatment options for CRVO were also included. Many treatment modalities have been demonstrated to be safe and efficacious in the treatment of CRVO. These treatment options offer therapeutic benefits for patients and clinically superior visual acuity and perhaps the quality of life after suffering from a CRVO. PMID:26957838

  7. Argon laser panretinal photocoagulation in ischemic central retinal vein occlusion. A 10-year prospective study.

    PubMed

    Hayreh, S S; Klugman, M R; Podhajsky, P; Servais, G E; Perkins, E S

    1990-01-01

    We conducted a prospective, planned study of argon laser panretinal photocoagulation (PRP) in ischemic central retinal vein occlusion (CRVO) over a 10-year period in 123 eyes. On comparing the lasered eyes versus the nonlasered eyes, there was no statistically significant difference between the two groups in the incidence of development of angle neovascularization (NV), neovascular glaucoma (NVG), retinal and/or optic disc NV, or vitreous hemorrhage, or in visual acuity. Our study, however, did show a statistically significant (P = 0.04) difference in the incidence of iris NV between the two groups, with iris NV less prevalent in the laser group than in the nonlaser group, but only when the PRP was performed within 90 days after the onset of CRVO. The other parameter which showed a statistically significant difference between the two groups was the peripheral visual fields-the laser group suffered a significantly (P less than or equal to 0.03) greater loss than the non-laser group. We discuss the implications of these findings in light of the natural history of ischemic CRVO and of ocular NV. Since the original rationale for advocating PRP in ischemic CRVO was the proven beneficial effect of PRP on ocular NV in proliferative diabetic retinopathy, we also discuss the disparities in the disease process between ischemic CRVO and proliferative diabetic retinopathy and in their responses to PRP. PMID:1698170

  8. Central retinal artery occlusion following orbital tumor resection: Is rapid intervention effective?

    PubMed

    Rajabi, Mohammad Taher; Naderan, Mohammad; Mohammadi, Seyed Ziaeddin Tabatabaei; Rajabi, Mohammad Bagher

    2015-08-01

    A 52-year-old male patient presented at our hospital with unilateral proptosis and vision loss in his left eye. Imaging evaluations showed orbital tumor, so the patient underwent surgery. About an hour later after tumor removal, patient developed sudden vision loss and became no light perception. Fundus evaluation revealed central retinal artery occlusion (CRAO). The patient was treated immediately with ocular massage and anterior chamber paracentesis as well as systemic therapy with mannitol and intravenous administration of acetazolamide. After thirty minutes, he recovered perception to light and then hand motion and 2 h later, it was improved to 1 m counting finger. CRAO following orbital tumor has not been reported before. We recommend ocular examination in all patients that undergo orbital surgery immediately to 2-3 h after surgery. PMID:26576528

  9. A case of central retinal artery occlusion following embolization procedure for juvenile nasopharyngeal angiofibroma

    PubMed Central

    Ramezani, Alireza; Haghighatkhah, Hamidreza; Moghadasi, Habibollah; Taheri, Morteza S; Parsafar, Hiva

    2010-01-01

    A 23-year-old male patient with right nasal Juvenile Nasopharyngeal Angiofibroma (JNA) developed Central Retinal Artery Occlusion (CRAO) during embolization of the tumor using polyvinyl alcohol particles before endoscopic excision. Classic CRAO management was initiated by an ophthalmologist after 12 h. Retrospective evaluation of the angiograms revealed a tiny communication between the external carotid and ophthalmic arteries which had not been noticed before embolization. During endoscopic excision, the tumor was found to originate extraordinarily from midline structures. It was concluded that CRAO might be a rare complication of JNA embolization. Careful preoperative angiographic evaluations to detect communicating arteries and immediate ophthalmologic consultation in case of developing visual symptoms during the procedure are necessary. PMID:20689199

  10. A case of central retinal artery occlusion following embolization procedure for juvenile nasopharyngeal angiofibroma.

    PubMed

    Ramezani, Alireza; Haghighatkhah, Hamidreza; Moghadasi, Habibollah; Taheri, Morteza Sanei; Parsafar, Hiva

    2010-01-01

    A 23-year-old male patient with right nasal Juvenile Nasopharyngeal Angiofibroma (JNA) developed Central Retinal Artery Occlusion (CRAO) during embolization of the tumor using polyvinyl alcohol particles before endoscopic excision. Classic CRAO management was initiated by an ophthalmologist after 12 h. Retrospective evaluation of the angiograms revealed a tiny communication between the external carotid and ophthalmic arteries which had not been noticed before embolization. During endoscopic excision, the tumor was found to originate extraordinarily from midline structures. It was concluded that CRAO might be a rare complication of JNA embolization. Careful preoperative angiographic evaluations to detect communicating arteries and immediate ophthalmologic consultation in case of developing visual symptoms during the procedure are necessary.

  11. Central retinal vein occlusion in an otherwise healthy child treated successfully with a single injection of bevacizumab.

    PubMed

    Zheng, Linda; Gillies, Mark; Martin, Frank J

    2015-10-01

    We describe the case of an otherwise healthy 13-year-old boy who presented with blurred vision and deteriorating visual acuity in his left eye. Fundus examination showed left optic disk swelling, exudates, and hemorrhages. He was found to have an elevated left central retinal venous pressure to the level of arterial diastolic pressure, an elevated left central macular thickness and a prolonged disk-to-disk transit time on fluorescein angiography, which confirmed the diagnosis of unilateral central retinal vein occlusion (CRVO). The child was treated with one injection of bevacizumab. He has maintained visual acuity of 6/6 for 2 years following treatment, despite persistent elevated left central venous pressure and chronic optic disk edema. PMID:26486035

  12. Retinal Disorders

    MedlinePlus

    ... be serious enough to cause blindness. Examples are Macular degeneration - a disease that destroys your sharp, central vision Diabetic eye disease Retinal detachment - a medical emergency, when the retina is ... children. Macular pucker - scar tissue on the macula Macular hole - ...

  13. Acute retinal necrosis (ARN) in the context of neonatal HSV-2 exposure and subconjunctival dexamethasone: case report and literature review.

    PubMed

    McGrath, Lindsay; Woods, Marion; Lee, Lawrence; Conrad, Diana

    2013-01-01

    HSV-2 is an important cause of the acute retinal necrosis (ARN) syndrome in younger patients. We describe an atypical case of HSV-2 ARN in the context of neonatal exposure and subconjunctival steroid injection. Clinicians should be aware of the association of neonatal or congenital exposure to HSV-2 as a risk factor for this disease because early treatment may improve outcome and/or avoid involvement of both eyes.

  14. X-linked retinitis pigmentosa: Report of a large kindred with loss of central vision and preserved peripheral function

    SciTech Connect

    Shastry, B.S.; Trese, M.T.

    1995-11-20

    X-linked retinitis pigmentosa (XLRP) is the most severe form of the inherited forms of retinitis pigmentosa and is clinically variable and genetically heterogeneous. It affects one in 20,000 live births. The affected individuals manifest degeneration of the peripheral retina during the first two decades of life on the basis of night blindness. Central vision usually is preserved until age 50, when the disease advances, affecting central vision and ultimately leading to complete loss of sight. Linkage analysis has shown two loci with a possibility of a third locus on the human X chromosome. The genetic abnormality that causes XLRP is not known at present. Here we describe a large kindred which manifests central loss of field with the preservation of peripheral vision. 5 refs., 1 fig.

  15. Drug treatment of macular oedema secondary to central retinal vein occlusion: a network meta-analysis

    PubMed Central

    Ford, John A; Shyangdan, Deepson; Uthman, Olalekan A; Lois, Noemi; Waugh, Norman

    2014-01-01

    Objective To indirectly compare aflibercept, bevacizumab, dexamethasone, ranibizumab and triamcinolone for treatment of macular oedema secondary to central retinal vein occlusion using a network meta-analysis (NMA). Design NMA. Data sources The following databases were searched from January 2005 to March 2013: MEDLINE, MEDLINE In-process, EMBASE; CDSR, DARE, HTA, NHSEED, CENTRAL; Science Citation Index and Conference Proceedings Citation Index-Science. Eligibility criteria for selecting studies Only randomised controlled trials assessing patients with macular oedema secondary to central retinal vein occlusion were included. Studies had to report either proportions of patients gaining ≥3 lines, losing ≥3 lines, or the mean change in best corrected visual acuity. Two authors screened titles and abstracts, extracted data and undertook risk of bias assessment. Bayesian NMA was used to compare the different interventions. Results Seven studies, assessing five drugs, were judged to be sufficiently comparable for inclusion in the NMA. For the proportions of patients gaining ≥3 lines, triamcinolone 4 mg, ranibizumab 0.5 mg, bevacizumab 1.25 mg and aflibercept 2 mg had a higher probability of being more effective than sham and dexamethasone. A smaller proportion of patients treated with triamcinolone 4 mg, ranibizumab 0.5 mg or aflibercept 2 mg lost ≥3 lines of vision compared to those treated with sham. Patients treated with triamcinolone 4 mg, ranibizumab 0.5 mg, bevacizumab 1.25 mg and aflibercept 2 mg had a higher probability of improvement in the mean best corrected visual acuity compared to those treated with sham injections. Conclusions We found no evidence of differences between ranibizumab, aflibercept, bevacizumab and triamcinolone for improving vision. The antivascular endothelial growth factors (VEGFs) are likely to be favoured because they are not associated with steroid-induced cataract formation. Aflibercept may be preferred by

  16. Acute retinal necrosis in the United Kingdom: results of a prospective surveillance study

    PubMed Central

    Cochrane, T F; Silvestri, G; McDowell, C; Foot, B; McAvoy, C E

    2012-01-01

    Background To determine the incidence of acute retinal necrosis (ARN) in the United Kingdom and to describe the demographics, management, and visual outcome in these patients. Methods This was a prospective study carried out by the British Ophthalmological Surveillance Unit (BOSU) between September 2007 and October 2008. Initial and 6-month questionnaires were sent to UK ophthalmologists who reported cases of ARN via the monthly BOSU report card system. Results In all, 45 confirmed cases (52 eyes) of ARN were reported in the 14-month study period, giving a minimum incidence of 0.63 cases per million population per year. There were 20 females and 25 males. Age ranged from 10 to 94 years. Eight patients had a history of herpetic CNS disease. Aqueous sampling was carried out in 13 patients, vitreous in 27, and cerebrospinal fluid (CSF) in 4. Varicella-zoster virus followed by herpes simplex were the most common causative agents. Treatment in 76% of the cases was with intravenous antivirals; however, 24% received only oral antivirals. In all, 47% of patients had intravitreal antiviral therapy. Visual outcome at 6 months was <6/60 in 48% of the affected eyes. Conclusion The minimum incidence of ARN in the UK is 0.63 cases per million. Patients with a history of herpetic CNS disease should be warned to immediately report any visual symptoms. There is increased use of oral and intravitreal antivirals in initial treatment. PMID:22281865

  17. Central diabetes insipidus in children with acute brain insult.

    PubMed

    Yang, Yun-Hsuan; Lin, Jainn-Jim; Hsia, Shao-Hsuan; Wu, Chang-Teng; Wang, Huei-Shyong; Hung, Po-Cheng; Chou, Min-Liang; Hsieh, Meng-Ying; Lin, Kuang-Lin

    2011-12-01

    Central diabetes insipidus occurs in patients with overwhelming central nervous system injuries, and may be associated with brain death. The clinical picture of children with acquired central diabetes insipidus after acute brain insult is seldom reported. We retrospectively reviewed cases dating from January 2000-February 2008 at a tertiary pediatric intensive care unit. Fifty-four patients (28 girls, 26 boys), aged 3 months to 18 years, were enrolled. Etiologies included severe central nervous system infection (35.2%), hypoxic-ischemic events (31.5%), head injury (18.5%), and vascular lesions (14.8%). In 39 (72.2%) patients, diabetes insipidus was diagnosed during the first 2 days after acute central nervous system injury, and 40 (74.0%) developed maximum serum sodium concentrations of >160 mEq/L. In 16, sequential cerebral salt wasting syndrome developed after their initial diabetes insipidus presentation. Overall mortality at 2 months after admission was 77.8%. Our results demonstrate that patients who develop central diabetes insipidus after acute central nervous system injury manifest high mortality. Development of central diabetes insipidus within the first 2 days and a maximum plasma sodium >160 mEq/L were significant predictors of outcomes.

  18. Thrombolytic therapy for central retinal vein occlusion: results of a pilot study.

    PubMed Central

    Elman, M J

    1996-01-01

    OBJECTIVE: To evaluate the feasibility of conducting a randomized, controlled trial of thrombolytic therapy for central retinal vein occlusion (CRVO) using tissue plasminogen activator (TPA); to establish relative efficacy and safety of various dosing regimens. DESIGN AND PATIENTS: Ninety-six patients with CRVO were treated with TPA between May 1986 and December 1992. Prior to patient enrollment, a standardized, detailed protocol was developed for evaluation and treatment of all patients. This included standard protocols for determining eligibility, reporting complications, performing photography and electroretinography, and measuring visual acuity. MAIN OUTCOME MEASURES: Best corrected visual acuity at 6 months, systemic and ophthalmic treatment complications. RESULTS: At 6 months' follow-up, 42% (n = 89) of eyes gained three or more lines of vision from pretreatment levels (average gain, 5.1 lines), 37% remained stable, and 21% lost three or more lines. Of eyes with 20/100 or worse pretreatment vision (n = 32), 59% gained three or more lines vision (average gain, 6.4 lines), 31% remained stable, and 9% lost three or more lines. One patient suffered a fatal stroke. Three patients developed intraocular bleeding during TPA administration. CONCLUSION: Thromobolytic therapy with TPA appears to be a promising, albeit risky, new treatment; conclusive evaluation of safety and efficacy awaits a multicenter, randomized, clinical trial; feasibility of such a trial has been established by this study. Images FIGURE 4 FIGURE 5 FIGURE 6 PMID:8981710

  19. Vision Loss by Central Retinal Vein Occlusion After Kaatsu Training: A Case Report.

    PubMed

    Ozawa, Yoko; Koto, Takashi; Shinoda, Hajime; Tsubota, Kazuo

    2015-09-01

    Kaatsu training is an exercise method involving the application of pressure to the target muscle, and is being increasingly used in rehabilitation programs for heart disease patients in some hospitals. This method restricts blood flow to the muscles during exercise, and the resultant hypoxia effectively causes muscle hypertrophy and strengthening. However, no medical guidelines or risk factors for its use have been established.We report a case involving a 45-year-old man who suffered from 2 episodes of central retinal vein occlusion (CRVO), both occurring on the day following a Kaatsu training session.As a characteristic of the CRVO and its subsequent complications, the affected eye lost vision despite treatment. The patient had a history of hypertension and diabetes, and thus was at an increased risk of CRVO. Kaatsu training, which changes the heart rate and serum growth hormone levels, may have triggered the onset of CRVO.This case highlights that underlying medical conditions such as hypertension, diabetes, and the consequent inflammation, could be risk factors for vascular side effects resulting from Kaatsu training. Further studies are required before the medical and recreational use of Kaatsu training become widespread. PMID:26356723

  20. Early panretinal photocoagulation for the treatment of ischemic central retinal vein occlusion

    NASA Astrophysics Data System (ADS)

    Yu, Zikui; He, Naizhen

    2005-07-01

    Objective: To evaluate the safety and efficacy of treating ischemic central retinal vein occlusion (CRVO)with early panretinal photocoagulation(PRP). Methods:24 eyes of 24 cases suffered from ischemic CRVO with history shorter than 3 months were included in this study. PRP treatments were completed through 3 to 5 times of laser therapy with total laser burns of 1000 to 2000(mean 1505+/-384).Patients were followed up 3 months to 2 years, mean 18.4+/-8.0 months.The neovascularization regression and visual acuity were compared before and after PRP, also the long-term complications were observed. Results:3 eyes of iris neovascularization (INV) regressed after PRP and there was no significant difference in visual acuity between prelaser and postlaser. No neovascular glaucoma(NVG) occurred and 2 eyes occurred vitreous hemorrhage during the follow up period.. Conclusions: Early panretinal photocoagulation is safe and efficacious in preventing and reducing complications of ischemic CRVO. It can save valuable treatment time for some patients

  1. Central retinal artery occlusion following laser treatment for ocular ischemic aortic arch syndrome

    PubMed Central

    Shah, Payal J.; Ellis, Brian; DiGiovine, Lauren R.; Hogg, Jeffery P.; Leys, Monique J.

    2015-01-01

    Objective: Ocular ischemic syndrome is a rare blinding condition generally caused by disease of the carotid artery. We describe a 69-year-old female with a 50 pack-year smoking history with aortic arch syndrome causing bilateral ocular ischemic syndrome. Methods: The patient presented with progressive visual loss and temple pain. Slit lamp biomicroscopy revealed bilateral iris neovascularization. This finding prompted a cardiovascular work up. Panretinal photocoagulation with retrobulbar block was performed in the right eye. Results: A temporal artery biopsy was negative. The carotid duplex ultrasound showed only a 1–39% stenosis. MRA revealed a more proximal occlusion of the aortic branch for which she underwent subclavian carotid bypass surgery. At the one month follow up, the right eye suffered profound vision loss secondary to a central retinal artery occlusion. Conclusion: Ocular neovascularization may be one of the clinical manifestations of aortic arch syndrome. This case also illustrates the limitations of relying solely on carotid duplex ultrasound testing. We caution against overly aggressive panretinal photocoagulation utilizing retrobulbar anesthesia.

  2. The association of central retinal artery occlusion and extracranial carotid artery disease.

    PubMed Central

    Douglas, D J; Schuler, J J; Buchbinder, D; Dillon, B C; Flanigan, D P

    1988-01-01

    To determine the incidence of associated carotid artery disease and the effect of carotid endarterectomy on subsequent neurologic sequelae, a retrospective study of 66 patients with central retinal artery occlusion (CRAO) was undertaken. Ipsilateral extracranial carotid artery disease was present in 23 of 33 patients (70%) who had carotid arteriography. Sixteen patients had carotid endarterectomy following their CRAO (Group I) and 50 did not (Group II). Seven of the 40 patients available for follow-up in Group II had a subsequent stroke (mean follow-up: 54 months). Of the seven Group II patients shown to have associated carotid disease (Group IIs), three (43%) had a subsequent stroke during follow-up (mean: 28.3 months) compared to zero in Group I (p = 0.033; mean follow-up: 18.7 months). Because of the strong association between CRAO and ipsilateral carotid artery disease and because of the significantly higher incidence of subsequent ipsilateral stroke in CRAO patients with carotid disease who did not undergo endarterectomy, thorough evaluation of the carotid arteries followed by carotid endarterectomy, if indicated, is warranted in CRAO patients who have no other obvious etiology for the occlusion. PMID:3389947

  3. Assessment of visual function and retinal structure following acute light exposure in the light sensitive T4R rhodopsin mutant dog.

    PubMed

    Iwabe, Simone; Ying, Gui-Shuang; Aguirre, Gustavo D; Beltran, William A

    2016-05-01

    weeks post LE with more severe damage at 36 weeks post LE in all four meridians. The RHO(T4R/T4R) retina exposed to the high dose showed at 2 weeks after LE extensive ONL damage in all four meridians. This light intensity did not cause any retinal damage in WT dogs even after repeated (up to 3) LE. Analysis of ONL thickness in heterozygous mutant dogs exposed to the moderate dose of light confirmed the increased sensitivity to light damage of the superior/tapetal retina, and the occurrence of an ongoing cell death process several weeks after the acute LE. In conclusion, a short single exposure to a dose of white light that is not retinotoxic in WT dogs causes in the T4R RHO retina an acute loss of ONL in the central to mid peripheral region that keeps progressing over the course of several weeks. However, this severe retinal damage does not affect visual behavior presumably because of islands of surviving photoreceptors found in the area centralis including the newly discovered canine fovea-like area, and the lack of damage to peripheral photoreceptors. PMID:27085210

  4. ASSESSMENT OF VISUAL FUNCTION AND RETINAL STRUCTURE FOLLOWING ACUTE LIGHT EXPOSURE IN THE LIGHT SENSITIVE T4R RHODOPSIN MUTANT DOG

    PubMed Central

    Iwabe, Simone; Ying, Gui-Shuang; Aguirre, Gustavo D.; Beltran, William A.

    2016-01-01

    severe damage at 36 weeks post LE in all four meridians. The RHOT4R/T4R retina exposed to the high dose showed at 2 weeks after LE extensive ONL damage in all four meridians. This light intensity did not cause any retinal damage in WT dogs even after repeated (up to 3) LE. Analysis of ONL thickness in heterozygous mutant dogs exposed to the moderate dose of light confirmed the increased sensitivity to light damage of the superior/tapetal retina, and the occurrence of an ongoing cell death process several weeks after the acute LE. In conclusion, a short single exposure to a dose of white light that is not retinotoxic in WT dogs causes in the T4R RHO retina an acute loss of ONL in the central to mid peripheral region that keeps progressing over the course of several weeks. However, this severe retinal damage does not affect visual behavior presumably because of islands of surviving photoreceptors found in the area centralis including the newly discovered canine fovea-like area, and the lack of damage to peripheral photoreceptors. PMID:27085210

  5. Risk factors for central and branch retinal vein occlusion: a meta-analysis of published clinical data.

    PubMed

    Kolar, Petr

    2014-01-01

    Retinal vein occlusion (RVO) is a major cause of vision loss. Of the two main types of RVO, branch retinal vein occlusion (BRVO) is 4 to 6 times more prevalent than central retinal vein occlusion (CRVO). A basic risk factor for RVO is advancing age. Further risk factors include systemic conditions like hypertension, arteriosclerosis, diabetes mellitus, hyperlipidemia, vascular cerebral stroke, blood hyperviscosity, and thrombophilia. A strong risk factor for RVO is the metabolic syndrome (hypertension, diabetes mellitus, and hyperlipidemia). Individuals with end-organ damage caused by diabetes mellitus and hypertension have greatly increased risk for RVO. Socioeconomic status seems to be a risk factor too. American blacks are more often diagnosed with RVO than non-Hispanic whites. Females are, according to some studies, at lower risk than men. The role of thrombophilic risk factors in RVO is still controversial. Congenital thrombophilic diseases like factor V Leiden mutation, hyperhomocysteinemia and anticardiolipin antibodies increase the risk of RVO. Cigarette smoking also increases the risk of RVO as do systemic inflammatory conditions like vasculitis and Behcet disease. Ophthalmic risk factors for RVO are ocular hypertension and glaucoma, higher ocular perfusion pressure, and changes in the retinal arteries. PMID:25009743

  6. Branch retinal vein occlusion.

    PubMed

    Hamid, Sadaf; Mirza, Sajid Ali; Shokh, Ishrat

    2008-01-01

    Retinal vein occlusions (RVO) are the second commonest sight threatening vascular disorder. Branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) are the two basic types of vein occlusion. Branch retinal vein occlusion is three times more common than central retinal vein occlusion and- second only to diabetic retinopathy as the most common retinal vascular cause of visual loss. The origin of branch retinal vein occlusion undoubtedly includes both systemic factors such as hypertension and local anatomic factors such as arteriovenous crossings. Branch retinal vein occlusion causes a painless decrease in vision, resulting in misty or distorted vision. Current treatment options don't address the underlying aetiology of branch retinal vein occlusion. Instead they focus on treating sequelae of the occluded venous branch, such as macular oedema, vitreous haemorrhage and traction retinal detachment from neovascularization. Evidences suggest that the pathogenesis of various types of retinal vein occlusion, like many other ocular vascular occlusive disorders, is a multifactorial process and there is no single magic bullet that causes retinal vein occlusion. A comprehensive management of patients with retinal vascular occlusions is necessary to correct associated diseases or predisposing abnormalities that could lead to local recurrences or systemic event. Along with a review of the literature, a practical approach for the management of retinal vascular occlusions is required, which requires collaboration between the ophthalmologist and other physicians: general practitioner, cardiologist, internist etc. as appropriate according to each case. PMID:19385476

  7. Central Retinal Enrichment Supplementation Trials (CREST): Design and Methodology of the CREST Randomized Controlled Trials

    PubMed Central

    Beatty, Stephen; Stack, Jim; Dennison, Jessica; O’Regan, Sarah; Meagher, Katherine A.; Peto, Tunde; Nolan, John

    2014-01-01

    Purpose The Central Retinal Enrichment Supplementation Trials (CREST) aim to investigate the potential impact of macular pigment (MP) enrichment, following supplementation with a formulation containing 10 mg lutein (L), 2 mg zeaxanthin (Z) and 10 mg meso-zeaxanthin (MZ), on visual function in normal subjects (Trial 1) and in subjects with early age-related macular degeneration (AMD; Trial 2). Methods CREST is a single center, double-blind, randomized clinical trial. Trial 1 (12-month follow-up) subjects are randomly assigned to a formulation containing 10 mg L, 10 mg MZ and 2 mg Z (n = 60) or placebo (n = 60). Trial 2 (24-month follow-up) subjects are randomly assigned to a formulation containing 10 mg L, 10 mg MZ, 2 mg Z plus 500 mg vitamin C, 400 IU vitamin E, 25 mg zinc and 2 mg copper (Intervention A; n = 75) or 10 mg L and 2 mg Z plus 500 mg vitamin C, 400 IU vitamin E, 25 mg zinc and 2 mg copper (Intervention B; n = 75). Contrast sensitivity (CS) at 6 cycles per degree represents the primary outcome measure in each trial. Secondary outcomes include: CS at other spatial frequencies, MP, best-corrected visual acuity, glare disability, photostress recovery, light scatter, cognitive function, foveal architecture, serum carotenoid concentrations, and subjective visual function. For Trial 2, AMD morphology, reading speed and reading acuity are also being recorded. Conclusions CREST is the first study to investigate the impact of supplementation with all three macular carotenoids in the context of a large, double-blind, randomized clinical trial. PMID:24621122

  8. Retinitis Pigmentosa

    MedlinePlus

    ... Action You are here Home › Retinal Diseases Listen Retinitis Pigmentosa What is retinitis pigmentosa? What are the symptoms? ... available? Are there any related diseases? What is retinitis pigmentosa? Retinitis pigmentosa (RP) refers to a group of ...

  9. Manifestations of central retinal artery occlusion revealed by fundus fluorescein angiography are associated with the degree of visual loss

    PubMed Central

    GONG, HONGXIA; SONG, QIUYING; WANG, LANHUI

    2016-01-01

    The aim of this study was to investigate the association between central visual impairment and the characteristics of fundus fluorescein angiography (FFA) in patients with central retinal artery occlusion (CRAO). A total of 63 patients were diagnosed with CRAO by FFA. The visual dysfunction was classified into severe, mild and light degrees. Tropicamide was administered for mydriasis. FFA examination was performed using Heidelberg retinal tomography. The associations of age, gender and disease course with CRAO type were analyzed. Three types of manifestations were identified by FFA in 63 eyes, including poor perfusion (18 cases), exudation (22 cases) and mixed types (23 cases) of CRAO. No significant difference was found in age (F=0.171, P=0.844) and disease course (F=0.016, P=0.984) among the three types of CRAO. Similarly, no significant difference was found in gender among the three types of CRAO (χ2=0.176, P=0.916). The damage to vision caused by the exudation type of CRAO was not as severe as that caused by the poor perfusion and mixed types of CRAO. The distributions of damage severity caused by the poor perfusion and mixed types of CRAO were similar. In conclusion, the FFA observations for CRAO can be classified into three types of manifestations. The damage to vision in patients with CRAO is likely to be associated with poor perfusion in the retinal artery rather than exudation affecting the retina or optic disc. The patterns of clinical manifestations are not associated with age, gender or disease course. PMID:27313672

  10. Combined Central Retinal Artery and Vein Occlusion Associated with Factor V Leiden Mutation and Treated with Hyperbaric Oxygen

    PubMed Central

    Lemos, José Alberto; Teixeira, Carla; Carvalho, Rui; Fernandes, Tiago

    2015-01-01

    Background Combined central retinal artery occlusion (CRAO) and central retinal vein occlusion (CRVO) is an uncommon retinal vascular disease which causes sudden visual acuity loss and is associated with poor prognosis and the development of severe complications. We report a very rare case of combined CRAO and CRVO in a patient with factor V Leiden (FVL) mutation (only 3 cases published). To our knowledge, this is the first case of combined CRAO and CRVO treated with hyperbaric oxygen therapy (HBOT). Case and Results A 49-year-old woman presented with complaints of sudden loss of vision in her left eye (LE), with best corrected visual acuity (BCVA) of 1/20. A complete ophthalmic evaluation with fundus angiography showed combined CRAO and CRVO. The patient was urgently treated with HBOT (she completed a total of 9 sessions in 7 days), with marked visual acuity and angiographic improvement (BCVA of 10/10). Forty-five days later, she developed a new LE CRVO, and BCVA decreased to 5/10 and later to <1/20 because of significant macular edema. A detailed investigation showed an abnormal resistance to activated protein C, and a genetic study showed homozygosity for FVL mutation. The patient was submitted to 3 monthly injections of 1.25 mg bevacizumab. After 10 months, the patient is in a stable condition with BCVA of 6/10. Conclusions Combined CRAO and CRVO in young adults should be investigated thoroughly for embolic sources, thrombophilic disorders and local ocular conditions. This is the first case of this severe disease that was treated with HBOT, and the visual result was very good. PMID:26955350

  11. Gravity sensing in the retinal spreading depression, an in-vitro model for the central nervous system (CNS)

    NASA Astrophysics Data System (ADS)

    Wiedemann, Meike; Piffel, Alexandra; Hanke, Wolfgang

    2005-08-01

    The retinal spreading depression (SD) was used to study the effects of altered gravity on the central nervous system (CNS). The SD is an excitation depression wave and an example of self-organization and pattern formation in neuronal tissue being an excitable media. Until now it is not much known about how changes in gravity effect the central nervous system. Here we present the results of SD experiments on a sounding rocket mission (TEXUS 41) and the comparison to earlier SD experiments on parabolic flights (2nd and 3rd DLR Parabolic flight campaign) and centrifuge experiments in our lab. The results of these experimetns show that the properties of the SD and therefore the CNS in its properties as an excitable medium reacts very sensitive to changes in gravity.

  12. Increased Risk of Acute Angle Closure in Retinitis Pigmentosa: A Population-Based Case-Control Study

    PubMed Central

    Ko, Yu-Chieh; Liu, Chia-Jen; Hwang, De-Kuang; Chen, Tzeng-Ji; Liu, Catherine J.

    2014-01-01

    Purpose To investigate the association between retinitis pigmentosa (RP) and acute angle closure during a 15-year follow-up period. Methods Using the Taiwan Longitudinal Health Insurance Database 2000, we identified 382 RP patients based on the diagnostic code of RP (International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) 362.74) made during 1996–2010, excluding subjects under age of 20 years at diagnosis or subjects undergoing lens extraction before the index date. The control group included 3820 randomly selected non-RP subjects matched with the RP patients in age, gender and the index date of diagnosis. The incidence of acute angle closure during the study period was observed based on an ICD-9-CM code of 365.22. Cochran-Mantel-Haenszel test was used to determine the odds ratio (OR) of having acute angle closure in RP patients. Results The mean age at the diagnosis of RP was 51.1years (standard deviation [SD] 16.7). Acute angle closure occurred in 5 RP patients (1.3%) and in 15 controls (0.4%). The mean age with the acute angle closure was 53.3 years (SD 8.0) in RP patients and 64.6 years (SD 8.4) in controls (P = 0.015). After adjusting for age, gender and comorbid disorders, RP patients had 3.64-fold (95% confidence interval [CI], 1.29–10.25, P<0.001) greater odds of having acute angle closure. After stratification for gender and age, the risk of acute angle closure in RP was higher in patients under age of 60 years (adjusted OR 11.84; 95% CI, 2.84–49.48) and male patients (adjusted OR 19.36; 95% CI, 3.43–109.40)(both P = 0.001). Conclusions RP patients had increased risk of acute angle closure than controls. Contrary to the fact that angle closure disease is more prevalent in elderly females in general population, acute angle closure attack occurred earlier in life and the risk was higher in males among RP patients. PMID:25222486

  13. Anterior Lamina Cribrosa Surface Depth in Open-Angle Glaucoma: Relationship with the Position of the Central Retinal Vessel Trunk

    PubMed Central

    Oh, Baek-Lok; Kim, Hyunjoong; Girard, Michaël J. A.; Mari, Jean Martial; Kim, Tae-Woo

    2016-01-01

    Purpose To determine the factors influencing the anterior lamina cribrosa (LC) surface depth (LCD) in patients with open-angle glaucoma (OAG), focusing on the association between LCD and the position of the central retinal vessel trunk (CRVT) at the anterior LC surface. Methods Optic nerve heads of 205 OAG eyes were scanned using swept-source optical coherence tomography (SS-OCT). After processing the images using adaptive compensation, the LCD was determined from 11 horizontal B-scan images that divided the optic disc vertically into 12 equal parts. Eyes were divided into two groups (central or peripheral) according to where the CRVT exits from the anterior LC surface. The influence of CRVT position on LCD was evaluated, taking into account age, gender, untreated intraocular pressure (IOP), IOP at optic-disc scanning, retinal nerve fiber layer (RNFL) thickness, visual-field mean deviation, central corneal thickness, and axial length. Results Patients in the peripheral CRVT group were younger and more myopic, and had a larger mean LCD and thinner global RNFL than those in the central CRVT group (all P≤0.023). On multivariate analysis, the peripheral CRVT location was significantly associated with a larger LCD (P = 0.002), together with the significant association of younger age (P<0.001), higher untreated IOP (P = 0.010), and thinner RNFL (P = 0.003) on the larger LCD. Conclusion In OAG, CRVT location was an independent factor influencing the LCD, together with age, untreated IOP, and global RNFL thickness. The data indicate that the CRVT may contribute to the resistance of the LC against deformation. A longitudinal prospective observation is required to clarify this relationship. PMID:27355646

  14. The Relationship between OCT-measured Central Retinal Thickness and Visual Acuity in Diabetic Macular Edema

    PubMed Central

    2008-01-01

    Objective To compare optical coherence tomography (OCT)-measured retinal thickness and visual acuity in eyes with diabetic macular edema (DME) both before and after macular laser photocoagulation. Design Cross-sectional and longitudinal study. Participants 210 subjects (251 eyes) with DME enrolled in a randomized clinical trial of laser techniques. Methods Retinal thickness was measured with OCT and visual acuity was measured with the electronic-ETDRS procedure. Main Outcome Measures OCT-measured center point thickness and visual acuity Results The correlation coefficients for visual acuity versus OCT center point thickness were 0.52 at baseline and 0.49, 0.36, and 0.38 at 3.5, 8, and 12 months post-laser photocoagulation. The slope of the best fit line to the baseline data was approximately 4.4 letters (95% C.I.: 3.5, 5.3) better visual acuity for every 100 microns decrease in center point thickness at baseline with no important difference at follow-up visits. Approximately one-third of the variation in visual acuity could be predicted by a linear regression model that incorporated OCT center point thickness, age, hemoglobin A1C, and severity of fluorescein leakage in the center and inner subfields. The correlation between change in visual acuity and change in OCT center point thickening 3.5 months after laser treatment was 0.44 with no important difference at the other follow-up times. A subset of eyes showed paradoxical improvements in visual acuity with increased center point thickening (7–17% at the three time points) or paradoxical worsening of visual acuity with a decrease in center point thickening (18%–26% at the three time points). Conclusions There is modest correlation between OCT-measured center point thickness and visual acuity, and modest correlation of changes in retinal thickening and visual acuity following focal laser treatment for DME. However, a wide range of visual acuity may be observed for a given degree of retinal edema and paradoxical

  15. SPG11 mutations cause Kjellin syndrome, a hereditary spastic paraplegia with thin corpus callosum and central retinal degeneration.

    PubMed

    Orlén, Hanna; Melberg, Atle; Raininko, Raili; Kumlien, Eva; Entesarian, Miriam; Söderberg, Per; Påhlman, Magnus; Darin, Niklas; Kyllerman, Mårten; Holmberg, Eva; Engler, Henry; Eriksson, Urban; Dahl, Niklas

    2009-10-01

    Autosomal recessive hereditary spastic paraplegia (ARHSP) with thin corpus callosum (TCC) is genetically heterogenous and approximately 35% of patients carry mutations in either of the SPG11 or SPG15 genes. Disease onset is during the first three decades of life with spastic paraplegia and mental impairment. Peripheral neuropathy and amyotrophy may occur. Kjellin syndrome is characterized by central retinal degeneration in addition to ARHSP-TCC and the disease is associated with mutations in the SPG15 gene. We identified five patients in four unrelated kindreds with spastic paraplegia and mental impairment. Magnetic resonance imaging revealed TCC, atrophy elsewhere in the brain and increased T2 signal intensity in the periventricular white matter. Probands from the four kindreds were screened for mutations in the SPG11 gene. All patients were found homozygous or compound heterozygous for truncating SPG11 mutations of which four are reported for the first time. Ophthalmological investigations revealed that the four index cases have central retinal degeneration consistent with Kjellin syndrome. PET examinations with N-[11C-methyl]-L-deuterodeprenyl (DED) and fluor-18 2-fluorodeoxyglucose (FDG) were performed in two patients with Kjellin syndrome. We observed a reduced glucose uptake in the thalami, anterior cingulum, and sensorimotor cortex indicating neuronal loss, and an increased DED binding in the thalami and pons which suggests astrogliosis. From our results we extend the SPG11 associated phenotype to comprise also Kjellin syndrome, previously found to be associated with mutations in the SPG15 gene. We anticipate that degeneration of the central retina is a common and previously unrecognized feature in SPG11 related disease.

  16. Vision Loss due to Central Retinal Artery Occlusion Following Embolization in a Case of a Giant Juvenile Nasopharyngeal Angiofibroma.

    PubMed

    Trivedi, Mihir; Desai, Roshani J; Potdar, Nayana A; Shinde, Chhaya A; Ukirde, Vivek; Bhuta, Maunil; Nair, Akshay Gopinathan

    2015-07-01

    Juvenile nasopharyngeal angiofibroma (JNA) is a benign, vascular, and locally aggressive tumor that arises in the nasal cavity, extending into the nasopharynx and often in to the orbit. It may rarely present to the ophthalmologist with proptosis and optic neuropathy. Preoperative embolization of JNA is done before surgical resection. In this communication, the authors report a rare occurrence of ipsilateral central retinal artery occlusion (CRAO) following embolization with polyvinyl alcohol in a 13-year-old boy with right-sided JNA. Retrospective review of the angiograms pointed out to a suspicious communication between the external carotid artery and the ophthalmic vessels. Pre-embolization detailed study of the angiograms is necessary to avoid such devastating complications. Although rare, vision loss is a possible complication arising from embolization of nasopharyngeal and intracranial tumors, and all patients undergoing these procedures should be informed of the risk of visual loss because it has a lasting impact on the quality of life.

  17. A Rare Cause of Unilateral Central Retinal Vein Occlusion in a Young Patient: Type III Mixed Cryoglobulinemia

    PubMed Central

    Sekeroglu, Mehmet Ali; Anayol, Mustafa Alpaslan; Yilmazbas, Pelin

    2016-01-01

    Purpose. To report a young male with unilateral central retinal vein occlusion (CRVO) associated with cryoglobulinemia. Case Presentation. A 33-year-old male without any known systemic or ocular disorder was admitted to our clinic with a complaint of visual loss for three days in his left eye. Based on the clinical, laboratory, and ophthalmological assessments, we diagnosed this case as type III mixed cryoglobulinemia with unilateral CRVO with macular edema. For treatment, two intravitreal ranibizumab injections were administered monthly and oral prednisone (64 mg/day) was begun. Subsequently, cryoglobulins became undetectable, macular edema decreased, and the visual acuity improved to 20/32 over an 8-week period. At 24 weeks, the patient's visual acuity remained 20/32 and no recurrence was observed while the patient was still on prednisone (16 mg/day). Conclusion. Cryoglobulinemia should be considered in the differential diagnosis of the patients with CRVO. PMID:27418988

  18. Combination Systemic and Intravitreal Antiviral Therapy in The Management of Acute Retinal Necrosis Syndrome (An American Ophthalmological Society Thesis)

    PubMed Central

    Flaxel, Christina J.; Yeh, Steven; Lauer, Andreas K.

    2013-01-01

    Purpose: To compare the outcomes of combination systemic and intravitreal antiviral therapy vs systemic antiviral therapy alone for treating acute retinal necrosis syndrome (ARN). We hypothesize that combination therapy might result in superior visual acuity (VA) and retinal detachment (RD) outcomes vs traditional systemic antiviral therapy alone. Methods: A retrospective, interventional, comparative single-center study of patients with ARN. We reviewed demographic data, herpesvirus diagnoses, polymerase chain reaction (PCR) results, VA, RD, and the use of systemic and intravitreal antiviral therapy. Outcome measures included VA improvement by 2 or more lines, severe visual loss, VA ≤20/200, and RD. Results: We studied 29 eyes of 24 patients, treated from 1987 through 2009. Mean age was 42.6 years and mean follow-up was 44.0 months. Twelve patients (14 eyes) were treated with combined systemic and intravitreal antiviral therapy and 12 patients (15 eyes) with systemic therapy alone. Kaplan-Meier survival analysis revealed that patients receiving combination intravitreal and systemic antiviral therapy were more likely to have VA improved by 2 lines or greater (P=.006). Patients receiving combination therapy also showed a decreased incidence of progression to severe visual loss (0.13/patient-years [PY]) compared to patients receiving systemic therapy alone (0.54/PY, P=.02) and had decreased incidence of RD (0.29/PY vs 0.74/PY, P=.03). Conclusions: Combination oral and intravitreal antiviral therapy may improve visual and functional outcomes in patients with ARN. Clinicians should consider prompt administration of combination systemic and intravitreal antiviral therapy as first-line treatment for patients with clinical features of ARN. PMID:24385671

  19. Topical Nepafenac in Treatment of Acute Central Serous Chorioretinopathy

    PubMed Central

    Alkin, Zeynep; Osmanbasoglu, Ozen Ayranci; Ozkaya, Abdullah; Karatas, Gonul; Yazici, Ahmet Taylan

    2013-01-01

    This study had been performed to investigate the anatomic and functional outcomes of nepafenac 0.1% therapy in acute central serous chorioretinopathy (CSC). The medical records of 30 patients with acute CSC were reviewed for a total of 31 eye charts. Seventeen eye records of 16 patients who were treated with topical nepafenac 0.1% three times daily for four weeks and continued until complete resolution of subretinal fluid were appraised. Fourteen patients with acute CSC (a total of 14 eye records) who did not receive treatment served as the control group also had been recorded. The proportion of eyes with complete resolution of subretinal fluid, serial changes in the mean best corrected visual acuity (BCVA), and the mean central foveal thickness (CFT) at 6 months of therapy were the outcomes measured. Mean age was 42.6±8.2 years in the treatment group and 41.1±7.1 years in the control group (p=0.85). At 6 months, 14 eyes (82.3%) in the treatment group and 6 eyes (42.8%) in the control group revealed a complete resolution in the subretinal fluid (p=0.02). In the treatment group, mean BCVA (LogMAR) significantly improved from 0.19±0.17 at baseline to 0.09±0.12 at 6 months (p=0.01). In the control group, mean BCVA (LogMAR) was 0.13±0.14 at baseline and decreased to 0.1±0.11 at 6 months (p=0.28). In the treatment group, mean CFT was 349±115 µm at baseline and significantly improved to 221±95 µm at 6 months (p<0.01). In the control group, mean CFT declined from 391±138 µm at baseline to 301±125 µm at 6 months (p=0.06). No treatment-related ocular or systemic side effects were observed. In conclusion, nepafenac 0.1% has the potential to treatment acute CSC. Further trials are warranted to study its safety and efficacy for this disease. PMID:24822228

  20. Time-dependent retinal ganglion cell loss, microglial activation and blood-retina-barrier tightness in an acute model of ocular hypertension.

    PubMed

    Trost, A; Motloch, K; Bruckner, D; Schroedl, F; Bogner, B; Kaser-Eichberger, A; Runge, C; Strohmaier, C; Klein, B; Aigner, L; Reitsamer, H A

    2015-07-01

    Glaucoma is a group of neurodegenerative diseases characterized by the progressive loss of retinal ganglion cells (RGCs) and their axons, and is the second leading cause of blindness worldwide. Elevated intraocular pressure is a well known risk factor for the development of glaucomatous optic neuropathy and pharmacological or surgical lowering of intraocular pressure represents a standard procedure in glaucoma treatment. However, the treatment options are limited and although lowering of intraocular pressure impedes disease progression, glaucoma cannot be cured by the currently available therapy concepts. In an acute short-term ocular hypertension model in rat, we characterize RGC loss, but also microglial cell activation and vascular alterations of the retina at certain time points. The combination of these three parameters might facilitate a better evaluation of the disease progression, and could further serve as a new model to test novel treatment strategies at certain time points. Acute ocular hypertension (OHT) was induced by the injection of magnetic microbeads into the rat anterior chamber angle (n = 22) with magnetic position control, leading to constant elevation of IOP. At certain time points post injection (4d, 7d, 10d, 14d and 21d), RGC loss, microglial activation, and microvascular pericyte (PC) coverage was analyzed using immunohistochemistry with corresponding specific markers (Brn3a, Iba1, NG2). Additionally, the tightness of the retinal vasculature was determined via injections of Texas Red labeled dextran (10 kDa) and subsequently analyzed for vascular leakage. For documentation, confocal laser-scanning microscopy was used, followed by cell counts, capillary length measurements and morphological and statistical analysis. The injection of magnetic microbeads led to a progressive loss of RGCs at the five time points investigated (20.07%, 29.52%, 41.80%, 61.40% and 76.57%). Microglial cells increased in number and displayed an activated morphology

  1. Predictors of short-term outcomes related to central subfield foveal thickness after intravitreal bevacizumab for macular edema due to central retinal vein occlusion

    PubMed Central

    Wang, Mei-Zi; Feng, Kang; Lu, Yao; Qian, Fang; Lu, Xin-Rong; Zang, Si-Wen; Zhao, Lin

    2016-01-01

    AIM To investigate the predictive factors for short-term effects of intravitreal bevacizumab injections on central subfield foveal thickness (CSFT) in patients with macular edema (ME) secondary to central retinal vein occlusion (CRVO). METHODS This was a retrospective study in 60 eyes treated with intravitreal bevacizumab injections for ME due to CRVO. Follow-up was three months. The Early Treatment Diabetic Retinopathy Study (ETDRS) score and CSFT measured by spectral-domain optical coherence tomography (SD-OCT) were used to observe the changes in best-corrected visual acuity (BCVA). Baseline BCVA, CSFT, age, CRVO duration and the presence of cystoid macular edema (CME) or subretinal fluid (SRF) were analyzed as potential predictive factors of the effects of intravitreal bevacizumab injections. RESULTS BCVA improved from 0.9 logMAR at baseline to 0.6 logMAR at 3mo, which was associated with a significant reduction in CSFT from 721 µm to 392 µm 3mo after injection. About 50% of CME cases and more than 90% of SRF cases responded to treatment with a complete resolution at 3mo. Age (P=0.036) and low baseline CSFT (P=0.037) were associated with a good 3-month prognosis. Patients >60 years old achieved better CME resolution (P=0.031) and lower CSFT at 3mo (305 µm vs 474 µm, P=0.003). CONCLUSION Intravitreal bevacizumab significantly improved visual acuity and CSFT in patients with CRVO after 3mo. Older age and lower baseline CSFT were good predictors of short-term CSFT outcomes. The retinal thickness response to bevacizumab might depend on the resolution of CME rather than SRF. PMID:26949616

  2. Central venous catheter infection in adults in acute hospital settings.

    PubMed

    Jones, Clare A

    As well as the human cost, central venous catheter (CVC)-related bloodstream infections significantly inflate hospital costs, mainly through increased length of stay in hospital, particularly in intensive care. This literature review appraises recent research on measures used to minimize CVC-related infection and compares it with current best practice. Randomized controlled trials and systematic reviews published on the subject between 2000 and 2005 were reviewed, concentrating on non-tunnelled, short-term CVCs in the acute hospital setting. The new evidence mainly backs up current best practice. However, skin disinfection could be improved by using alcoholic chlorhexidine followed by aqueous povidone-iodine before CVC insertion. Also, alcoholic chlorhexidine is the preferred solution for cleaning the hubs/connectors before accessing the CVC. Good hand hygiene and quality control and education programmes are vital to improve patient care. More research is needed to clarify the effectiveness of certain interventions and technologies, such as antimicrobial CVCs.

  3. Isolated central nervous system relapse of acute lymphoblastic leukemia.

    PubMed

    Sung, Sang-Hyun; Jang, In-Seok

    2014-10-01

    Acute lymphoblastic leukemia (ALL) is the most common form of childhood cancer and may exhibit central nervous system (CNS) involvement. Advances in chemotherapy and effective CNS prophylaxis have significantly decreased the incidence of CNS relapse of ALL to 5-10%. Here, we report the case of a patient with isolated CNS relapse of standard risk group pre-B-cell type ALL in an 11-year-old girl, relapsed 3 years after successful completion of chemotherapy. An 11-year-old girl visited our hospital complaining of headache, dizziness, vomiting, and visual field defects. Neurological examination revealed left-side homonymous hemianopsia. Brain magnetic resonance imaging showed a large irregular dural-based sulcal hematoma in the right parietal and occipital lobes. Surgery to remove the hematoma revealed the existence of hematopoietic malignancy after pathologic evaluation. Bone marrow biopsy was subsequently performed but showed no evidence of malignancy. PMID:25408936

  4. Relatively spared central multifocal electroretinogram responses in acute quinine toxicity

    PubMed Central

    Saeed, Muhammad Usman; Noonan, Carmel; Hagan, Richard; Brown, Malcolm

    2011-01-01

    A 71-year-old man was investigated with electrodiagnostic testing 4 months after a deliberate quinine overdose. Initially he was admitted to intensive care unit with visual acuity (VA) of perception of light in both eyes. VA recovered to 6/6 right eye and 6/12 left eye, though severely constricted fields were noted. Slow stimulus (base period of 83 ms) multifocal electroretinogram (ERG) showed electronegative responses outside the inner 5 degrees, with a reduced but electropositive response seen in this central area. It appears that in this case of bilaterally negative ERGs that the macula/fovea (which has a vascular supply through the choroid) is relatively spared as is seen in bilateral vascular electronegative ERGs. This may indicate that quinine toxicity to the retina may be secondary to effects similar to vascular occlusion or severe ischemia during the acute phase of quinine poisoning. PMID:22693278

  5. Centrally Administered Ghrelin Acutely Influences Food Choice in Rodents

    PubMed Central

    Schéle, Erik; Bake, Tina; Rabasa, Cristina; Dickson, Suzanne L.

    2016-01-01

    We sought to determine whether the orexigenic hormone, ghrelin, is involved in the intrinsic regulation of food choice in rats. Ghrelin would seem suited to serve such a role given that it signals hunger information from the stomach to brain areas important for feeding control, including the hypothalamus and reward system (e.g. ventral tegmental area, VTA). Thus, in rats offered a choice of palatable foods (sucrose pellets and lard) superimposed on regular chow for 2 weeks, we explored whether acute central delivery of ghrelin (intracerebroventricular (ICV) or intra-VTA) is able to redirect their dietary choice. The major unexpected finding is that, in rats with high baseline lard intake, acute ICV ghrelin injection increased their chow intake over 3-fold, relative to vehicle-injected controls, measured at both 3 hr and 6 hr after injection. Similar effects were observed when ghrelin was delivered to the VTA, thereby identifying the VTA as a likely contributing neurobiological substrate for these effects. We also explored food choice after an overnight fast, when endogenous ghrelin levels are elevated, and found similar effects of dietary choice to those described for ghrelin. These effects of fasting on food choice were suppressed in models of suppressed ghrelin signaling (i.e. peripheral injection of a ghrelin receptor antagonist to rats and ghrelin receptor (GHSR) knock-out mice), implicating a role for endogenous ghrelin in the changes in food choice that occur after an overnight fast. Thus, in line with its role as a gut-brain hunger hormone, ghrelin appears to be able to acutely alter food choice, with notable effects to promote “healthy” chow intake, and identify the VTA as a likely contributing neurobiological substrate for these effects. PMID:26925974

  6. Retinal pathways influence temporal niche

    PubMed Central

    Doyle, Susan E.; Yoshikawa, Tomoko; Hillson, Holly; Menaker, Michael

    2008-01-01

    In mammals, light input from the retina entrains central circadian oscillators located in the suprachiasmatic nuclei (SCN). The phase of circadian activity rhythms with respect to the external light:dark cycle is reversed in diurnal and nocturnal species, although the phase of SCN rhythms relative to the light cycle remains unchanged. Neural mechanisms downstream from the SCN are therefore believed to determine diurnality or nocturnality. Here, we report a switch from nocturnal to diurnal entrainment of circadian activity rhythms in double-knockout mice lacking the inner-retinal photopigment melanopsin (OPN4) and RPE65, a key protein used in retinal chromophore recycling. These mice retained only a small amount of rod function. The change in entrainment phase of Rpe65−/−;Opn4−/− mice was accompanied by a reversal of the rhythm of clock gene expression in the SCN and a reversal in acute masking effects of both light and darkness on activity, suggesting that the nocturnal to diurnal switch is due to a change in the neural response to light upstream from the SCN. A switch from nocturnal to diurnal activity rhythms was also found in wild-type mice transferred from standard intensity light:dark cycles to light:dark cycles in which the intensity of the light phase was reduced to scotopic levels. These results reveal a novel mechanism by which changes in retinal input can mediate acute temporal-niche switching. PMID:18695249

  7. Central Glaucomatous Damage of the Macula Can Be Overlooked by Conventional OCT Retinal Nerve Fiber Layer Thickness Analyses

    PubMed Central

    Wang, Diane L.; Raza, Ali S.; de Moraes, Carlos Gustavo; Chen, Monica; Alhadeff, Paula; Jarukatsetphorn, Ravivarn; Ritch, Robert; Hood, Donald C.

    2015-01-01

    Purpose To assess the extent to which glaucomatous damage of the macula can be detected using the summary statistics of a commercial report based upon the circumpapillary retinal nerve fiber layer (cpRNFL) thickness obtained with frequency domain optical coherence tomography (fdOCT). Methods One hundred forty-three eyes of 143 open-angle glaucoma patients and suspects (56.4 ± 13.8 years) had 10-2 visual fields (VFs) and fdOCT macular and disc cube scans. RNFL and retinal ganglion cell plus inner plexiform layer thickness and probability maps were generated and combined with 10-2 VF information in a single-page, custom report previously described. Three graders evaluated these reports and classified each eye as “abnormal macula” or “normal macula.” Commercially available fdOCT reports for cpRNFL thickness were generated using the automatic segmentation algorithm and norms from the machine. The ability of the reports to detect macular damage was analyzed in three ways: temporal quadrant (TQ) < 5%; TQ < 5% or clock hour 7 < 1% (TQ + CH7); and clock hours 7 through 10 with two sectors < 5% or one sector < 1% (CH7−10). Results Sixty-one (43%) eyes were classified “abnormal macula” and 41 (29%) as “normal macula”; the 10-2 VFs and OCT probability maps did not agree in the remaining eyes. Of the 61 abnormal eyes, the TQ criterion missed 47 (77%); TQ + CH7 missed 24 (39%); and CH7−10 missed 22 (36%). Conclusions Conventional cpRNFL analyses on commercial OCT reports can miss macular (central field) damage. Translational Relevance To detect glaucomatous damage of the macula, additional tests, such as macular cube scans and/or 10-2 VFs, should be performed. PMID:26644964

  8. One-year outcome of bevacizumab therapy for chronic macular edema in central and branch retinal vein occlusions in real-world clinical practice in the UK

    PubMed Central

    Lip, Peck Lin; Malick, Huzaifa; Damer, Kenan; Elsherbiny, Samer; Darrad, Kanupriya M; Mushtaq, Bushra; Mitra, Arijit; Stavrou, Panagiota; Yang, Yit

    2015-01-01

    Background The purpose of this study was to investigate the 12-month outcome of macular edema secondary to both chronic and new central and branch retinal vein occlusions treated with intravitreal bevacizumab in the real-life clinical setting in the UK. Methods Retrospective case notes analysis of consecutive patients with retinal vein occlusions treated with bevacizumab in 2010 to 2012. Outcome measures were visual acuity (measured with Snellen, converted into logMAR [logarithm of the minimum angle of resolution] for statistical calculation) and central retinal thickness at baseline, 4 weeks post-loading phase, and at 1 year. Results There were 56 and 100 patients with central and branch retinal vein occlusions, respectively, of whom 62% had chronic edema and received prior therapies and another 32% required additional laser treatments post-baseline bevacizumab. Baseline median visual acuity was 0.78 (interquartile range [IQR] 0.48–1.22) in the central group and 0.6 (IQR 0.3–0.78) in the branch group. In both groups, visual improvement was statistically significant from baseline compared to post-loading (P<0.001 and P=0.03, respectively), but was not significant by month 12 (P=0.058 and P=0.166, respectively); 30% improved by at least three lines and 44% improved by at least one line by month 12. Baseline median central retinal thickness was 449 μm (IQR 388–553) in the central group and 441 μm (IQR 357–501) in the branch group. However, the mean reduction in thickness was statistically significant at post-loading (P<0.001) and at the 12-month time point (P<0.001) for both groups. The average number of injections in 1 year was 4.2 in the central group and 3.3 in the branch group. Conclusion Our large real-world cohort results indicate that bevacizumab introduced to patients with either new or chronic edema due to retinal vein occlusion can result in resolution of edema and stabilization of vision in the first year. PMID:26445525

  9. Gray matter alterations in visual cortex of patients with loss of central vision due to hereditary retinal dystrophies.

    PubMed

    Plank, Tina; Frolo, Jozef; Brandl-Rühle, Sabine; Renner, Agnes B; Hufendiek, Karsten; Helbig, Horst; Greenlee, Mark W

    2011-06-01

    In patients with central visual field scotomata a large part of visual cortex is not adequately stimulated. Over time this lack of input could lead to a reduction of gray matter in the affected cortical areas. We used Voxel Based Morphometry to investigate structural brain changes in patients with central scotomata due to hereditary retinal dystrophies and compared their results to those of normal sighted subjects. Additionally we correlated clinical and demographic characteristics like duration of disease, scotoma size, visual acuity, fixation stability and reading speed to the amount of gray matter in whole brain analyses within the patient group. We found a decrease in gray matter around the lesion projection zone in visual cortex of patients in comparison to controls. Gray matter loss along the posterior and middle portions of the calcarine sulcus is also correlated with scotoma size, indicating that indeed the lack of functional input provokes the gray matter alterations. In whole brain regression analyses within the patient group we found an additional cluster in the right superior and middle frontal gyri, slightly anterior to the frontal eye fields, where gray matter correlated positively with fixation stability. This could be regarded as a consequence of oculomotor learning.

  10. Retinal vein occlusion and the risk of acute myocardial infarction development: a 12-year nationwide cohort study

    PubMed Central

    Rim, Tyler Hyungtaek; Han, John Seungsoo; Oh, Jaewon; Kim, Dong Wook; Kang, Seok-Min; Chung, Eun Jee

    2016-01-01

    The goal of this study was to evaluate the risk of developing acute myocardial infarction (AMI) following retinal vein occlusion (RVO). A retrospective cohort study was performed from the National Health Insurance Service and comprised 1,025,340 random subjects who were followed from 2002 to 2013. Patients with RVO in 2002 were excluded. The RVO group was composed of patients who received an initial RVO diagnosis between January 2003 and December 2007 (n = 1677). The comparison group was selected (five patients per RVO patient; n = 8367) using propensity score matching according to sociodemographic factors and the year of enrolment. Each patient was tracked until 2013. The Cox proportional hazard regression model was used. AMI developed in 7.6% of the RVO group and 5.3% of the comparison group (p < 0.001) for 7.7 median follow-up periods. RVO increased the risk of AMI development [hazard ratio (HR) = 1.25; 95% Confidence Interval (CI) 1.02 to 1.52]. In the subgroup analysis, RVO patients aged <65 years and the males within this age group had an adjusted HR of 1.47 (95% CI 1.10 to 1.98) and an adjusted HR of 2.00 (95% CI 1.38 to 2.91) for AMI development, respectively. RVO was significantly associated with AMI development. PMID:26924150

  11. Acute retinal necrosis caused by herpes simplex virus type 2 in children: reactivation of an undiagnosed latent neonatal herpes infection.

    PubMed

    Grose, Charles

    2012-09-01

    Herpes simplex virus type 2 (HSV-2) is known to cause acute retinal necrosis (ARN). The availability of HSV-2-specific polymerase chain reaction tests for diagnostic analysis has greatly increased our ability to discriminate ARN caused by HSV-2 from ARN caused by either herpes simplex virus type 1 or varicella zoster virus (VZV). Of great interest, HSV-2 appears to be the most common cause of viral ARN in children and adolescents. Although a few children with ARN are known to have had neonatally acquired herpes infection, most children lack a history of known herpes disease. Thus, the origin of the HSV-2 infection is a mystery. The hypothesis of this review is that HSV-2 ARN in children and adolescents may be the first sign of a previously undiagnosed and asymptomatic neonatal HSV-2 infection, which has reactivated several years later from latency in a cranial nerve and entered the retina. The review brings together 7 previously published ARN cases, plus one new case is added. Thus, this review also expands the spectrum of complications from neonatal HSV-2 infection.

  12. [Application of retinal oximeter in ophthalmology].

    PubMed

    Li, Jing; Ma, Jianmin; Wang, Ningli

    2015-11-01

    Retinal oximeter is a new machine which has been used in the diagnose, treatment and research of several ophthalmic diseases for recent years. It allows ophthalmologists to gain retinal oxygen saturation directly. Therefore, retinal oximeter might be useful for ophthalmologists to understand ophthalmic diseases more deeper and clarify the impact of ischemia on retinal function. It has been reported in the literatures that retinal oximeter has potentially useful diagnostic and therapeutic indications in various eye diseases such as diabetic retinopathy, central retinal vein and artery occlusion, retinitis pigmentosa, glaucomatous optic neuropathy, et al. In this thesis, the application of retinal oximeter in ophthalmology is reviewed.

  13. Assessment of Central Retinal Sensitivity Employing Two Types of Microperimetry Devices

    PubMed Central

    Liu, Hongting; Bittencourt, Millena G.; Wang, Jiangxia; Sophie, Raafay; Annam, Rachel; Ibrahim, Mohamed A.; Sepah, Yasir J.; Moradi, Ahmadreza; Scholl, Hendrik P. N.; Nguyen, Quan Dong

    2014-01-01

    Purpose To compare the retinal sensitivity measurements obtained with two microperimeters, the Micro-Perimeter 1 (MP-1) and the Optos optical coherence tomography (OCT)/scanning laser ophthalmoscope (SLO) in subjects with and without maculopathies. Methods Forty-five eyes with no known ocular disease and 47 eyes with maculopathies were examined using both microperimeters. A contrast-adjusted scale was applied to resolve the different stimuli and background luminance existing between the two devices. Results There was a strong ceiling effect with the MP-1 in the healthy group, with 90.1% (1136 of 1260) test points clustered at 20 dB. The mean sensitivity for the corresponding points in the OCT/SLO was 25.8 ± 1.9 dB. A floor effect was also observed with the OCT/SLO in the maculopathy group with 9.7% (128 of 1316) points clustered at 9-dB values. The corresponding mean sensitivity in the MP-1 was 1.7 ± 3.9 dB. A regression equation between the two microperimeters was established in the common 10 to19 dB intervals as: OCT/SLO = 15.6 + 0.564 × MP-1 − 0.009 × MP-12 + k (k is an individual point constant; MP-1 coefficient P < 0.001; MP-12 coefficient P = 0.006). Conclusion The OCT/SLO and the MP-1 provide two different ranges of contrasts for microperimetry examination. Broadening the dynamic range may minimize the constraint of the ceiling and floor effect. There is a significant mathematical relationship in the common interval of the contrast scale. Translational Relevance Applying a unified and broadened dynamic range in different types of microperimeters will help to generate consistent clinical reference for measurements. PMID:25237592

  14. [Differential magnetic resonance diagnosis of central lung cancer and acute pneumonia].

    PubMed

    Gamova, E V; Nudnov, N V

    2006-01-01

    The paper analyzes the authors' own data of chest magnetic resonance imaging (MRI) in 86 patients with verified central lung cancer and acute pneumonia. The MRI signs of lung cancer are systematized in exo-, endo-, and peribronchial forms of growth. The additional capacities of contrast enhancement are analyzed. The MRI semiotics of acute pneumonia has been developed. The differential diagnostic criteria for recognizing central lung cancer and acute pneumonia have been also elaborated.

  15. Interventions for asymptomatic retinal breaks and lattice degeneration for preventing retinal detachment

    PubMed Central

    Wilkinson, Charles P

    2015-01-01

    Background Asymptomatic retinal breaks and lattice degeneration are visible lesions that are risk factors for later retinal detachment. Retinal detachments occur when fluid in the vitreous cavity passes through tears or holes in the retina and separates the retina from the underlying retinal pigment epithelium. Creation of an adhesion surrounding retinal breaks and lattice degeneration, with laser photocoagulation or cryotherapy, has been recommended as an effective means of preventing retinal detachment. This therapy is of value in the management of retinal tears associated with the symptoms of flashes and floaters and persistent vitreous traction upon the retina in the region of the retinal break, because such symptomatic retinal tears are associated with a high rate of progression to retinal detachment. Retinal tears and holes unassociated with acute symptoms and lattice degeneration are significantly less likely to be the sites of retinal breaks that are responsible for later retinal detachment. Nevertheless, treatment of these lesions frequently is recommended, in spite of the fact that the effectiveness of this therapy is unproven. Objectives The objective of this review was to assess the effectiveness and safety of techniques used to treat asymptomatic retinal breaks and lattice degeneration for the prevention of retinal detachment. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2014, Issue 2), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to February 2014), EMBASE (January 1980 to February 2014), PubMed (January 1948 to February 2014), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in

  16. A novel coculture model of porcine central neuroretina explants and retinal pigment epithelium cells

    PubMed Central

    Di Lauro, Salvatore; Rodriguez-Crespo, David; Gayoso, Manuel J.; Garcia-Gutierrez, Maria T.; Pastor, J. Carlos; Srivastava, Girish K.

    2016-01-01

    Purpose To develop and standardize a novel organ culture model using porcine central neuroretina explants and RPE cells separated by a cell culture membrane. Methods RPE cells were isolated from porcine eyes, expanded, and seeded on the bottom of cell culture inserts. Neuroretina explants were obtained from the area centralis and cultured alone (controls) on cell culture membranes or supplemented with RPE cells in the same wells but physically separated by the culture membrane. Finally, cellular and tissue specimens were processed for phase contrast, cyto-/histological, and immunochemical evaluation. Neuroretina thickness was also determined. Results Compared to the neuroretinas cultured alone, the neuroretinas cocultured with RPE cells maintained better tissue structure and cellular organization, displayed better preservation of photoreceptors containing rhodopsin, lower levels of glial fibrillary acidic protein immunoexpression, and preservation of cellular retinaldehyde binding protein both markers of reactive gliosis. Neuroretina thickness was significantly greater in the cocultures. Conclusions A coculture model of central porcine neuroretina and RPE cells was successfully developed and standardized. This model mimics a subretinal space and will be useful in studying interactions between the RPE and the neuroretina and to preclinically test potential therapies. PMID:27081295

  17. Observation on therapeutic efficacy of rt-PA intravenous thrombolysis combined with compound anisodine injection on central retinal artery occlusion

    PubMed Central

    Wu, Xiao-Jun; Gao, Feng; Liu, Xu; Zhao, Qing

    2016-01-01

    The aim of the present study was to observe the clinical efficacy and safety of recombinant tissue plasminogen activator (rt-PA) combined with compound anisodine in treating central retinal artery occlusion (CRAO). Forty-eight patients diagnosed with CRAO were randomly divided into a treatment group (24 cases) and a control group (24 cases). For the control group, nitroglycerin, 654-2, methazolamide, puerarin and compound anisodine were used for the treatment, along with oxygen, massage and other conventional treatments. Besides conventional therapy, the treatment group was also given intravenous rt-PA thrombolysis. Visual acuity, fundus oculi, visual field changes were taken as indicators for efficacy evaluation. It was found that the total effective rate of the control group was 70.83%, while that for the treatment group was 91.67%, and the comparative difference between the two groups was of statistical significance (p<0.05). The visual field defect of the control group after treatment was approximately 74.26±12.91%, and the visual field defect of the treatment group after treatment approximately 35.08±16.33%; thus, the comparative difference was statistically significant (p<0.01). The comparative difference of the original contents of fibrous protein in blood in the treatment group before and after treatment was statistically significant (p<0.01). In conclusion, the result show that intravenous thrombolysis with rt-PA combined with compound anisodine is safe and effective in treating CRAO, which can significantly improve the prognosis of patients. PMID:27698763

  18. Observation on therapeutic efficacy of rt-PA intravenous thrombolysis combined with compound anisodine injection on central retinal artery occlusion

    PubMed Central

    Wu, Xiao-Jun; Gao, Feng; Liu, Xu; Zhao, Qing

    2016-01-01

    The aim of the present study was to observe the clinical efficacy and safety of recombinant tissue plasminogen activator (rt-PA) combined with compound anisodine in treating central retinal artery occlusion (CRAO). Forty-eight patients diagnosed with CRAO were randomly divided into a treatment group (24 cases) and a control group (24 cases). For the control group, nitroglycerin, 654-2, methazolamide, puerarin and compound anisodine were used for the treatment, along with oxygen, massage and other conventional treatments. Besides conventional therapy, the treatment group was also given intravenous rt-PA thrombolysis. Visual acuity, fundus oculi, visual field changes were taken as indicators for efficacy evaluation. It was found that the total effective rate of the control group was 70.83%, while that for the treatment group was 91.67%, and the comparative difference between the two groups was of statistical significance (p<0.05). The visual field defect of the control group after treatment was approximately 74.26±12.91%, and the visual field defect of the treatment group after treatment approximately 35.08±16.33%; thus, the comparative difference was statistically significant (p<0.01). The comparative difference of the original contents of fibrous protein in blood in the treatment group before and after treatment was statistically significant (p<0.01). In conclusion, the result show that intravenous thrombolysis with rt-PA combined with compound anisodine is safe and effective in treating CRAO, which can significantly improve the prognosis of patients.

  19. No influence of acute RF exposure (GSM-900, GSM-1800, and UMTS) on mouse retinal ganglion cell responses under constant temperature conditions.

    PubMed

    Ahlers, Malte T; Ammermüller, Josef

    2014-01-01

    Possible non-thermal effects of radio frequency electromagnetic fields (RF-EMF) on retinal ganglion cells were studied in vitro under conditions of constant temperature. Isolated mouse retinae were exposed to GSM-900, GSM-1800, and universal mobile telecommunication system (UMTS) RF-EMF applying specific absorption rates (SAR) of 0 (sham), 0.02, 0.2, 2, and 20 W/kg. Temperature was kept constant within ±0.5 to 1 °C for GSM-900 and ±0.5 °C for GSM-1800 and UMTS. Responses of retinal ganglion cells to light stimuli of three intensities (0.5, 16, and 445 lx) were recorded before, during, and up to 35 min after exposure. Experiments were performed under double-blind conditions. Changes in light responses during and after exposure were determined for each condition (RF-EMF; SAR value; light intensity) with respect to the responses before exposure, respectively. Changes were calculated using the Euclidian distance of the n-dimensional response vectors, respectively. Some changes already occurred during sham (0 W/kg) exposure, reflecting the intrinsic variability in retinal ganglion cell responses. Comparison of the distance values from sham exposure with those from actual exposure yielded no significant differences. In addition, linear regression analysis of the distance values versus SAR values yielded no consistent dependence of light response changes. From these results we conclude that RF-EMF exposure at three mobile phone frequencies (GSM-900, GSM-1800, UMTS) and SARs up to 20 W/kg has no acute effects on retinal ganglion cell responses under constant temperature conditions.

  20. α-Aminoadipic acid protects against retinal disruption through attenuating Müller cell gliosis in a rat model of acute ocular hypertension

    PubMed Central

    Wang, Xiaolei; Su, Jier; Ding, Jingwen; Han, Song; Ma, Wei; Luo, Hong; Hughes, Guy; Meng, Zhaoyang; Yin, Yi; Wang, Yanling; Li, Junfa

    2016-01-01

    Objective Ocular hypertension is an important risk factor for glaucoma. The purpose of this study was to investigate the gliotoxic effects of α-aminoadipic acid (AAA) in a rat model of AOH and its underlying mechanisms. Materials and methods In the rat model of acute ocular hypertension (AOH), intraocular pressure was increased to 110 mmHg for 60 minutes. Animals were divided into four groups: sham operation (Ctrl), AOH, AOH + phosphate-buffered saline (PBS), and AOH + AAA. Cell apoptosis in the ganglion cell layer was detected with the terminal deoxynucleotidyl transferase-mediated uridine 5′-triphosphate-biotin nick end labeling (TUNEL) assay, and retinal ganglion cells (RGCs) immunostained with Thy-1 were counted. Müller cell activation was detected using immunostaining with glutamine synthetase and glial fibrillary acidic protein. Tumor necrosis factor-α (TNF-α) was examined using Western blot. Results In the rat model of AOH, cell apoptosis was induced in the ganglion cell layer and the number of RGCs was decreased. Müller cell gliosis in the retinas of rats was induced, and retinal protein levels of TNF-α were increased. Intravitreal treatment of AAA versus PBS control attenuated these retinal abnormalities to show protective effects in the rat model of AOH. Conclusion In the retinas of the rat model of AOH, AAA treatment attenuated retinal apoptosis in the ganglion cell layer and preserved the number of RGCs, likely through the attenuation of Müller cell gliosis and suppression of TNF-α induction. Our observations suggest that AAA might be a potential therapeutic target in glaucoma. PMID:27799744

  1. Location and stability of a newly established eccentric retinal locus suitable for reading, achieved through training of patients with a dense central scotoma.

    PubMed

    Nilsson, U L; Frennesson, C; Nilsson, S E

    1998-12-01

    Six patients, median age 71 years, with a dense central scotoma in one eye and a median visual acuity of 0.06 (20/330) in the same eye, were all (100%) shown by means of fundus photography including a fixation target to preferably use an unfavorable retinal locus for fixation, i.e., within the lesion (scotoma). None of the patients was able to read novel text with the affected eye. A computer and video display system were used to determine the most suitable area above or below the visual field scotoma (below or above the retinal lesion) for reading and the magnification needed at this eccentricity. The same setup was also used for an introductory training in reading single words as well as scrolled text with the aim of establishing a preferred retinal locus (PRL) at a favorable, eccentric position, the trained retinal locus (TRL). Thereafter, the patients were provided with strong positive lenses (median power, 40 D) for reading printed text at a very short reading distance (median, 2.5 cm), first single words, above and below which help lines were printed to facilitate eccentric fixation, and finally, novel text. The total training time was 4 to 5 h. Thereafter, fundus photography showed that five of the patients (83%) used their TRL as their PRL. Reading speed was 71 words per minute (median). Our results seem to indicate that an eccentric PRL favorable for effective reading can be established through training and that a fairly low number of training sessions is required.

  2. Retinitis Pigmentosa.

    ERIC Educational Resources Information Center

    Carr, Ronald E.

    1979-01-01

    The author describes the etiology of retinitis pigmentosa, a visual dysfunction which results from progressive loss of the retinal photoreceptors. Sections address signs and symptoms, ancillary findings, heredity, clinical diagnosis, therapy, and research. (SBH)

  3. Phosphatase control of 4E-BP1 phosphorylation state is central for glycolytic regulation of retinal protein synthesis

    PubMed Central

    Gardner, Thomas W.; Abcouwer, Steven F.; Losiewicz, Mandy K.

    2015-01-01

    Control of protein synthesis in insulin-responsive tissues has been well characterized, but relatively little is known about how this process is regulated in nervous tissues. The retina exhibits a relatively high protein synthesis rate, coinciding with high basal Akt and metabolic activities, with the majority of retinal ATP being derived from aerobic glycolysis. We examined the dependency of retinal protein synthesis on the Akt-mTOR signaling and glycolysis using ex vivo rat retinas. Akt inhibitors significantly reduced retinal protein synthesis but did not affect glycolytic lactate production. Surprisingly, the glycolytic inhibitor 2-deoxyglucose (2-DG) markedly inhibited Akt1 and Akt3 activities, as well as protein synthesis. The effects of 2-DG, and 2-fluorodeoxyglucose (2-FDG) on retinal protein synthesis correlated with inhibition of lactate production and diminished ATP content, with all these effects reversed by provision of d-mannose. 2-DG treatment was not associated with increased AMPK, eEF2, or eIF2α phosphorylation; instead, it caused rapid dephosphorylation of 4E-BP1. 2-DG reduced total mTOR activity by 25%, but surprisingly, it did not reduce mTORC1 activity, as indicated by unaltered raptor-associated mTOR autophosphorylation and ribosomal protein S6 phosphorylation. Dephosphorylation of 4E-BP1 was largely prevented by inhibition of PP1/PP2A phosphatases with okadaic acid and calyculin A, and inhibition of PPM1 phosphatases with cadmium. Thus, inhibition of retinal glycolysis diminished Akt and protein synthesis coinciding with accelerated dephosphorylation of 4E-BP1 independently of mTORC1. These results demonstrate a novel mechanism regulating protein synthesis in the retina involving an mTORC1-independent and phosphatase-dependent regulation of 4E-BP1. PMID:26199279

  4. Phosphatase control of 4E-BP1 phosphorylation state is central for glycolytic regulation of retinal protein synthesis.

    PubMed

    Gardner, Thomas W; Abcouwer, Steven F; Losiewicz, Mandy K; Fort, Patrice E

    2015-09-15

    Control of protein synthesis in insulin-responsive tissues has been well characterized, but relatively little is known about how this process is regulated in nervous tissues. The retina exhibits a relatively high protein synthesis rate, coinciding with high basal Akt and metabolic activities, with the majority of retinal ATP being derived from aerobic glycolysis. We examined the dependency of retinal protein synthesis on the Akt-mTOR signaling and glycolysis using ex vivo rat retinas. Akt inhibitors significantly reduced retinal protein synthesis but did not affect glycolytic lactate production. Surprisingly, the glycolytic inhibitor 2-deoxyglucose (2-DG) markedly inhibited Akt1 and Akt3 activities, as well as protein synthesis. The effects of 2-DG, and 2-fluorodeoxyglucose (2-FDG) on retinal protein synthesis correlated with inhibition of lactate production and diminished ATP content, with all these effects reversed by provision of d-mannose. 2-DG treatment was not associated with increased AMPK, eEF2, or eIF2α phosphorylation; instead, it caused rapid dephosphorylation of 4E-BP1. 2-DG reduced total mTOR activity by 25%, but surprisingly, it did not reduce mTORC1 activity, as indicated by unaltered raptor-associated mTOR autophosphorylation and ribosomal protein S6 phosphorylation. Dephosphorylation of 4E-BP1 was largely prevented by inhibition of PP1/PP2A phosphatases with okadaic acid and calyculin A, and inhibition of PPM1 phosphatases with cadmium. Thus, inhibition of retinal glycolysis diminished Akt and protein synthesis coinciding with accelerated dephosphorylation of 4E-BP1 independently of mTORC1. These results demonstrate a novel mechanism regulating protein synthesis in the retina involving an mTORC1-independent and phosphatase-dependent regulation of 4E-BP1.

  5. Ruptured retinal arterial macroaneurysm: diagnosis and management.

    PubMed

    Speilburg, Ashley M; Klemencic, Stephanie A

    2014-01-01

    Retinal arterial macroaneurysm is an acquired, focal dilation of a retinal artery, typically occurring within the first three bifurcations of the central retinal artery. The clinical presentation of a retinal arterial macroaneurysm is highly variable, making initial diagnosis difficult and differentials many. Identification of retinal arterial macroaneurysms is crucial to appropriately co-manage with the primary care physician for hypertension control. Prognosis is generally good and observation is often an adequate treatment. However, in cases of macular threat or involvement, some treatment options are available and referral to a retinal specialist is indicated.

  6. Retinitis pigmentosa and retinal oedema.

    PubMed Central

    Spalton, D J; Bird, A C; Cleary, P E

    1978-01-01

    Twenty-five patients with retinitis pigmentosa and retinal leakage were investigated. Oedema was present in dominant and X-linked inherited disease and is likely to be present in recessive disease as well. We suggest that this might be a general response seen in many types of tapeto-retinal degeneration to actively degenerating photoreceptors or pigment epithelium. Images PMID:638111

  7. Acute pesticide poisoning and pesticide registration in Central America.

    PubMed

    Wesseling, Catharina; Corriols, Marianela; Bravo, Viria

    2005-09-01

    The International Code of Conduct on the Distribution and Use of Pesticides of the Food and Agriculture Organization (FAO) of the United Nations has been for 20 years the most acknowledged international initiative for reducing negative impact from pesticide use in developing countries. We analyzed pesticide use and poisoning in Central America, particularly in Costa Rica and Nicaragua, and evaluated whether registration decisions are based on such data, in accordance with the FAO Code. Extensive use of very hazardous pesticides continues in Central America and so do poisonings with organophosphates, carbamates, endosulfan and paraquat as the main causative agents. Central American governments do not carry out or commission scientific risk assessments. Instead, guidelines from international agencies are followed for risk management through the registration process. Documentation of pesticide poisonings during several decades never induced any decision to ban or restrict a pesticide. However, based on the official surveillance systems, in 2000, the ministers of health of the seven Central American countries agreed to ban or restrict twelve of these pesticides. Now, almost 4 years later, restrictions have been implemented in El Salvador and in Nicaragua public debate is ongoing. Chemical and agricultural industries do not withdraw problematic pesticides voluntarily. In conclusion, the registration processes in Central America do not comply satisfactorily with the FAO Code. However, international regulatory guidelines are important in developing countries, and international agencies should strongly extend its scope and influence, limiting industry involvement. Profound changes in international and national agricultural policies, steering towards sustainable agriculture based on non-chemical pest management, are the only way to reduce poisonings.

  8. Acute pesticide poisoning and pesticide registration in Central America

    SciTech Connect

    Wesseling, Catharina . E-mail: cwesseli@una.ac.cr; Corriols, Marianela; Bravo, Viria

    2005-09-01

    The International Code of Conduct on the Distribution and Use of Pesticides of the Food and Agriculture Organization (FAO) of the United Nations has been for 20 years the most acknowledged international initiative for reducing negative impact from pesticide use in developing countries. We analyzed pesticide use and poisoning in Central America, particularly in Costa Rica and Nicaragua, and evaluated whether registration decisions are based on such data, in accordance with the FAO Code. Extensive use of very hazardous pesticides continues in Central America and so do poisonings with organophosphates, carbamates, endosulfan and paraquat as the main causative agents. Central American governments do not carry out or commission scientific risk assessments. Instead, guidelines from international agencies are followed for risk management through the registration process. Documentation of pesticide poisonings during several decades never induced any decision to ban or restrict a pesticide. However, based on the official surveillance systems, in 2000, the ministers of health of the seven Central American countries agreed to ban or restrict twelve of these pesticides. Now, almost 4 years later, restrictions have been implemented in El Salvador and in Nicaragua public debate is ongoing. Chemical and agricultural industries do not withdraw problematic pesticides voluntarily. In conclusion, the registration processes in Central America do not comply satisfactorily with the FAO Code. However, international regulatory guidelines are important in developing countries, and international agencies should strongly extend its scope and influence, limiting industry involvement. Profound changes in international and national agricultural policies, steering towards sustainable agriculture based on non-chemical pest management, are the only way to reduce poisonings.

  9. The visual system of a palaeognathous bird: visual field, retinal topography and retino-central connections in the Chilean tinamou (Nothoprocta perdicaria).

    PubMed

    Krabichler, Quirin; Vega-Zuniga, Tomas; Morales, Cristian; Luksch, Harald; Marín, Gonzalo J

    2015-02-01

    Most systematic studies of the avian visual system have focused on Neognathous species, leaving virtually unexplored the Palaeognathae, comprised of the flightless ratites and the South American tinamous. We investigated the visual field, the retinal topography, and the pattern of retinal and centrifugal projections in the Chilean tinamou, a small Palaeognath of the family Tinamidae. The tinamou has a panoramic visual field with a small frontal binocular overlap of 20°. The retina possesses three distinct topographic specializations: a horizontal visual streak, a dorsotemporal area, and an area centralis with a shallow fovea. The maximum ganglion cell density is 61,900/ mm(2) , comparable to Falconiformes. This would provide a maximal visual acuity of 14.0 cycles/degree, in spite of relatively small eyes. The central retinal projections generally conform to the characteristic arrangement observed in Neognathae, with well-differentiated contralateral targets and very few ipsilateral fibers. The centrifugal visual system is composed of a considerable number of multipolar centrifugal neurons, resembling the "ectopic" neurons described in Neognathae. They form a diffuse nuclear structure, which may correspond to the ancestral condition shared with other sauropsids. A notable feature is the presence of terminals in deep tectal layers 11-13. These fibers may represent either a novel retinotectal pathway or collateral branches from centrifugal neurons projecting to the retina. Both types of connections have been described in chicken embryos. Our results widen the basis for comparative studies of the vertebrate visual system, stressing the conserved character of the visual projections' pattern within the avian clade. PMID:25224833

  10. Retinal detachment

    PubMed Central

    2010-01-01

    Introduction Rhegmatogenous retinal detachment (RRD) is the most common form of retinal detachment, where a retinal "break" allows the ingress of fluid from the vitreous cavity to the subretinal space, resulting in retinal separation. It occurs in about 1 in 10,000 people a year. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to prevent progression from retinal breaks or lattice degeneration to retinal detachment? What are the effects of different surgical interventions in people with rhegmatogenous retinal detachment? What are the effects of interventions to treat proliferative vitreoretinopathy occurring as a complication of retinal detachment or previous treatment for retinal detachment? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 21 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: corticosteroids, cryotherapy, daunorubicin, fluorouracil plus low molecular weight heparin, laser photocoagulation, pneumatic retinopexy, scleral buckling, short-acting or long-acting gas tamponade, silicone oil tamponade, and vitrectomy. PMID:21406128

  11. Color Doppler imaging of retinal diseases.

    PubMed

    Dimitrova, Galina; Kato, Satoshi

    2010-01-01

    Color Doppler imaging (CDI) is a widely used method for evaluating ocular circulation that has been used in a number of studies on retinal diseases. CDI assesses blood velocity parameters by using ultrasound waves. In ophthalmology, these assessments are mainly performed on the retrobulbar blood vessels: the ophthalmic, the central retinal, and the short posterior ciliary arteries. In this review, we discuss CDI use for the assessment of retinal diseases classified into the following: vascular diseases, degenerations, dystrophies, and detachment. The retinal vascular diseases that have been investigated by CDI include diabetic retinopathy, retinal vein occlusions, retinal artery occlusions, ocular ischemic conditions, and retinopathy of prematurity. Degenerations and dystrophies included in this review are age-related macular degeneration, myopia, and retinitis pigmentosa. CDI has been used for the differential diagnosis of retinal detachment, as well as the evaluation of retrobulbar circulation in this condition. CDI is valuable for research and is a potentially useful diagnostic tool in the clinical setting.

  12. Inhibition of acute inflammation in the periphery by central action of salicylates.

    PubMed Central

    Catania, A; Arnold, J; Macaluso, A; Hiltz, M E; Lipton, J M

    1991-01-01

    Understanding of the antiinflammatory actions of nonsteroidal drugs is incomplete, but these actions are believed to occur in the periphery, without any contribution from the central nervous system. Recent research on the antipyretic antiinflammatory neuropeptide alpha-melanocyte-stimulating hormone indicates that it can act centrally to inhibit peripheral inflammation; this raises the possibility that other agents, such as nonsteroidal antiinflammatory drugs, may have similar activity. In the present research both lysine acetylsalicylate and sodium salicylate inhibited edema, induced in the mouse ear by topical application of picryl chloride, when injected into the lateral cerebral ventricle. This inhibitory activity on a measure of acute inflammation was not due to escape of the drugs into the periphery, because systemic injection of doses that were effective centrally did not affect inflammation. In contrast, central administration of a dose of indomethacin that was antiinflammatory when given intraperitoneally did not inhibit peripheral inflammation. Thus indomethacin apparently lacks the central antiinflammatory action of the salicylates. This observation, plus our inability to demonstrate either an antiinflammatory effect of intracerebroventricular dexamethasone, a prostaglandin inhibitor, or a pro-inflammatory influence of prostaglandin E2, suggests that prostaglandins are not important to central modulation of inflammation. The results indicate that, in addition to having central influences on fever and pain, salicylates can act within the brain to inhibit acute inflammation in the periphery. Images PMID:1924313

  13. Retinal cartography.

    PubMed

    Mosier, M A

    1982-10-01

    This paper analyses retinal cartography in terms of its reflection of anatomic data and its relation to several forms of geographic methods of map-making. It shows that the distances between anatomic landmarks of the eye are reasonably similar to the relative distances on the retinal drawing chart currently used. Two forms of geographic cartography--azimuth equidistant and orthographic--are described and compared with retinal cartography. The retinal drawing chart currently used most closely approximates an azimuth equidistant projection, which suffers from circumferential distortion, a fact that retinal surgeons must keep in mind. It is therefore recommended that the chart be modified to have equally spaced concentric circles and clearer identification of the ora serrata; the present accurate marking of anatomic landmarks, such as the equator and the posterior border of the ciliary body, should be preserved.

  14. Central effect of histamine in a rat model of acute trigeminal pain.

    PubMed

    Tamaddonfard, Esmaeal; Khalilzadeh, Emad; Hamzeh-Gooshchi, Nasrin; Seiednejhad-Yamchi, Sona

    2008-01-01

    In conscious rats implanted with an intracerebroventricular (icv) cannula, effect of icv injections of histamine, chlorpheniramine (H(1)-receptor antagonist) and ranitidine (H(2)-receptor blocker) was investigated in a rat model of acute trigeminal pain. Acute trigeminal pain was induced by putting a drop of 5 M NaCl solution on the corneal surface of the eye and the numbers of eye wipes were counted during the first 30 s. Histamine (20, 40 microg) and chlorpheniramine (80 microg) significantly decreased the numbers of eye wipes. Ranitidine alone had no effect. Pretreatment with chlorpheniramine did not change the histamine-induced analgesia, whereas the histamine effect on pain was inhibited with ranitidine pretreatment. These results indicate that the brain histamine, through central H(2) receptors, may be involved in the modulation of the acute trigeminal pain in rats.

  15. Ocular lateropulsion as a central oculomotor sign in acute vestibular syndrome is not posturally dependent.

    PubMed

    Kattah, Jorge C; Pula, John; Newman-Toker, David E

    2011-09-01

    Horizontal conjugate gaze deviation (h-CGD) in acute vestibular syndrome (AVS) may be detected clinically or radiographically. While upright clinical ocular lateropulsion (OL) predicts central lesions, supine radiographic h-CGD does not. We sought to investigate the cause for this discordance by comparing upright to supine OL in AVS. We prospectively recorded clinical and radiographic h-CGD in 17 AVS patients. Horizontal eye position after brief eyelid closure was tested clinically following postural shifts. Radiographic h-CGD was assessed on axial magnetic resonance imaging (MRI) or computerized tomography (CT) images. All maintained central fixation with eyes open in light. OL was present in 8 (7 strokes, one central demyelination) and radiographic h-CGD in 14 (including all 6 with peripheral lesions). OL was unchanged after static postural testing. OL predicts central pathology and does not vary with postural shifts, regardless of lesion location. Radiographic h-CGD does not help localize, and this is not a positional effect.

  16. Retinal Prosthesis

    PubMed Central

    Weiland, James D.; Humayun, Mark S.

    2015-01-01

    Retinal prosthesis have been translated from the laboratory to the clinical over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa. These devices provide partial sight restoration and patients use this improved vision in their everyday lives. Improved mobility and object detection are some of the more notable findings from the clinical trials. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. This paper reviews the recent clinical trials, highlights technology breakthroughs that will contribute to next generation of retinal prostheses. PMID:24710817

  17. Catheter-directed Thrombolysis in Acute Superior Vena Cava Syndrome Caused by Central Venous Catheters.

    PubMed

    Cui, Jie; Kawai, Tasuo; Irani, Zubin

    2015-01-01

    Indwelling central venous catheters have been reported to increase the risk of superior venous cava (SVC) syndrome. This case report describes the development of acute SVC syndrome in a 28-year-old woman with end-stage renal disease implanted with a left-side hemodialysis reliable outflow graft and a right-side double lumen hemodialysis catheter via internal jugular veins. Her symptoms were not alleviated after catheter removal and systemic anticoagulation therapy. She was eventually treated with catheter-directed thrombolysis and a predischarge computer tomographic venogram on postthrombolytic procedure day 7 showed patent central veins and patient remained asymptomatic. This case demonstrates that catheter-directed thrombolysis can be safely employed to treat refractory catheter-induced acute SVC syndrome in end-stage renal disease patients.

  18. Infectious Etiologies of Acute Febrile Illness among Patients Seeking Health Care in South-Central Cambodia

    PubMed Central

    Kasper, Matthew R.; Blair, Patrick J.; Touch, Sok; Sokhal, Buth; Yasuda, Chadwick Y.; Williams, Maya; Richards, Allen L.; Burgess, Timothy H.; Wierzba, Thomas F.; Putnam, Shannon D.

    2012-01-01

    The agents of human febrile illness can vary by region and country suggesting that diagnosis, treatment, and control programs need to be based on a methodical evaluation of area-specific etiologies. From December 2006 to December 2009, 9,997 individuals presenting with acute febrile illness at nine health care clinics in south-central Cambodia were enrolled in a study to elucidate the etiologies. Upon enrollment, respiratory specimens, whole blood, and serum were collected. Testing was performed for viral, bacterial, and parasitic pathogens. Etiologies were identified in 38.0% of patients. Influenza was the most frequent pathogen, followed by dengue, malaria, and bacterial pathogens isolated from blood culture. In addition, 3.5% of enrolled patients were infected with more than one pathogen. Our data provide the first systematic assessment of the etiologies of acute febrile illness in south-central Cambodia. Data from syndromic-based surveillance studies can help guide public health responses in developing nations. PMID:22302857

  19. Infectious etiologies of acute febrile illness among patients seeking health care in south-central Cambodia.

    PubMed

    Kasper, Matthew R; Blair, Patrick J; Touch, Sok; Sokhal, Buth; Yasuda, Chadwick Y; Williams, Maya; Richards, Allen L; Burgess, Timothy H; Wierzba, Thomas F; Putnam, Shannon D

    2012-02-01

    The agents of human febrile illness can vary by region and country suggesting that diagnosis, treatment, and control programs need to be based on a methodical evaluation of area-specific etiologies. From December 2006 to December 2009, 9,997 individuals presenting with acute febrile illness at nine health care clinics in south-central Cambodia were enrolled in a study to elucidate the etiologies. Upon enrollment, respiratory specimens, whole blood, and serum were collected. Testing was performed for viral, bacterial, and parasitic pathogens. Etiologies were identified in 38.0% of patients. Influenza was the most frequent pathogen, followed by dengue, malaria, and bacterial pathogens isolated from blood culture. In addition, 3.5% of enrolled patients were infected with more than one pathogen. Our data provide the first systematic assessment of the etiologies of acute febrile illness in south-central Cambodia. Data from syndromic-based surveillance studies can help guide public health responses in developing nations.

  20. Acute influence of alcohol, THC or central stimulants on violent suicide: A Swedish population study.

    PubMed

    Lundholm, Lena; Thiblin, Ingemar; Runeson, Bo; Leifman, Anders; Fugelstad, Anna

    2014-03-01

    Alcohol and substance abuse in general is a risk factor for suicide, but very little is known about the acute effect in relation to suicide method. Based on information from 18,894 medico-legal death investigations, including toxicological findings and manner of death, did the present study investigate whether acute influence of alcohol, tetrahydrocannabinol (THC), or central stimulants (amphetamine and cocaine) was related to the use of a violent suicide method, in comparison with the nonviolent method self-poisoning and alcohol-/illicit drug-negative suicide decedents. Multivariate analysis was conducted, and the results revealed that acute influence of THC was related to using the violent suicide method–– jumping from a height (RR 1.62; 95% CI 1.01–2.41). Alcohol intoxication was not related to any violent method, while the central stimulant-positive suicide decedent had a higher, albeit not significant, risk of several violent methods. The study contributes with elucidating suicide methods in relation to acute intoxication. PMID:24745078

  1. Emerging roles of the acute phase protein pentraxin-3 during central nervous system disorders.

    PubMed

    Rajkovic, Ivana; Denes, Adam; Allan, Stuart M; Pinteaux, Emmanuel

    2016-03-15

    Pentraxin-3 (PTX3) is an acute phase protein (APP) and a member of the long pentraxin family that is recognised for its role in peripheral immunity and vascular inflammation in response to injury, infection and diseases such as atherosclerosis, cancer and respiratory disease. Systemic levels of PTX3 are highly elevated in these conditions, and PTX3 is now recognised as a new biomarker of disease risk and progression. There is extensive evidence demonstrating that central nervous system (CNS) disorders are primarily characterised by central activation of innate immunity, as well as activation of a potent peripheral acute phase response (APR) that influences central inflammation and contributes to poor outcome. PTX3 has been recently recognised to play important roles in CNS disorders, having both detrimental and neuroprotective effects. The present review aims to give an up-to-date account of the emerging roles of PTX3 in CNS disorders, and to provide a critical comparison between peripheral and central actions of PTX3 in inflammatory diseases.

  2. Identification of retinal ganglion cells and their projections involved in central transmission of information about upward and downward image motion.

    PubMed

    Yonehara, Keisuke; Ishikane, Hiroshi; Sakuta, Hiraki; Shintani, Takafumi; Nakamura-Yonehara, Kayo; Kamiji, Nilton L; Usui, Shiro; Noda, Masaharu

    2009-01-01

    The direction of image motion is coded by direction-selective (DS) ganglion cells in the retina. Particularly, the ON DS ganglion cells project their axons specifically to terminal nuclei of the accessory optic system (AOS) responsible for optokinetic reflex (OKR). We recently generated a knock-in mouse in which SPIG1 (SPARC-related protein containing immunoglobulin domains 1)-expressing cells are visualized with GFP, and found that retinal ganglion cells projecting to the medial terminal nucleus (MTN), the principal nucleus of the AOS, are comprised of SPIG1+ and SPIG1(-) ganglion cells distributed in distinct mosaic patterns in the retina. Here we examined light responses of these two subtypes of MTN-projecting cells by targeted electrophysiological recordings. SPIG1+ and SPIG1(-) ganglion cells respond preferentially to upward motion and downward motion, respectively, in the visual field. The direction selectivity of SPIG1+ ganglion cells develops normally in dark-reared mice. The MTN neurons are activated by optokinetic stimuli only of the vertical motion as shown by Fos expression analysis. Combination of genetic labeling and conventional retrograde labeling revealed that axons of SPIG1+ and SPIG1(-) ganglion cells project to the MTN via different pathways. The axon terminals of the two subtypes are organized into discrete clusters in the MTN. These results suggest that information about upward and downward image motion transmitted by distinct ON DS cells is separately processed in the MTN, if not independently. Our findings provide insights into the neural mechanisms of OKR, how information about the direction of image motion is deciphered by the AOS.

  3. Acute IOP elevation with scleral suction: effects on retrobulbar haemodynamics.

    PubMed Central

    Harris, A; Joos, K; Kay, M; Evans, D; Shetty, R; Sponsel, W E; Martin, B

    1996-01-01

    AIMS/BACKGROUND: Mechanical and vascular factors may both contribute to glaucoma. This study investigated the relation of mechanical to vascular factors by examining how acute IOP elevation altered flow velocities in the central retinal and ophthalmic arteries. METHODS: IOP was elevated from a baseline near 14 to approximately 45 mm Hg using suction ophthalmodynamometry. During recovery from scleral suction, IOP fell to near 8 mm Hg. At each IOP, peak systolic and end diastolic velocities (PSV and EDV) were measured in the central retinal and ophthalmic arteries using colour Doppler imaging (Siemens Quantum 2000). Eleven healthy people served as subjects. RESULTS: Acute elevation in IOP had no effect upon PSV, EDV, or the derived resistance index in the ophthalmic artery: flow velocities in this vessel were identical at IOP of 8 mm Hg or 45 mm Hg. In contrast, in the central retinal artery, PSV and EDV fell, and the resistance index rose, in steady progression as IOP was acutely elevated (each p < 0.01). At IOP of 45 mm Hg, EDV was virtually absent and the resistance index was very nearly 1.0. CONCLUSION: Ophthalmic arterial haemodynamics are unrelated to acute fluctuations of the IOP over a wide range, suggesting that ocular hypertension itself cannot induce vascular dysfunction in this artery. In contrast, flow velocities in the central retinal artery were highly IOP dependent, implying that haemodynamic and mechanical factors are closely linked in this vascular bed. PMID:9059269

  4. Effect of an acute increase in central blood volume on cerebral hemodynamics.

    PubMed

    Ogoh, Shigehiko; Hirasawa, Ai; Raven, Peter B; Rebuffat, Thomas; Denise, Pierre; Lericollais, Romain; Sugawara, Jun; Normand, Hervé

    2015-10-15

    Systemic blood distribution is an important factor involved in regulating cerebral blood flow (CBF). However, the effect of an acute change in central blood volume (CBV) on CBF regulation remains unclear. To address our question, we sought to examine the CBF and systemic hemodynamic responses to microgravity during parabolic flight. Twelve healthy subjects were seated upright and exposed to microgravity during parabolic flight. During the brief periods of microgravity, mean arterial pressure was decreased (-26 ± 1%, P < 0.001), despite an increase in cardiac output (+21 ± 6%, P < 0.001). During microgravity, central arterial pulse pressure and estimated carotid sinus pressure increased rapidly. In addition, this increase in central arterial pulse pressure was associated with an arterial baroreflex-mediated decrease in heart rate (r = -0.888, P < 0.0001) and an increase in total vascular conductance (r = 0.711, P < 0.001). The middle cerebral artery mean blood velocity (MCA Vmean) remained unchanged throughout parabolic flight (P = 0.30). During microgravity the contribution of cardiac output to MCA Vmean was gradually reduced (P < 0.05), and its contribution was negatively correlated with an increase in total vascular conductance (r = -0.683, P < 0.0001). These findings suggest that the acute loading of the arterial and cardiopulmonary baroreceptors by increases in CBV during microgravity results in acute and marked systemic vasodilation. Furthermore, we conclude that this marked systemic vasodilation decreases the contribution of cardiac output to CBF. These findings suggest that the arterial and cardiopulmonary baroreflex-mediated peripheral vasodilation along with dynamic cerebral autoregulation counteracts a cerebral overperfusion, which otherwise would occur during acute increases in CBV. PMID:26310936

  5. Invasive fungal infection of the central nervous system in a patient with acute myeloid leukaemia

    PubMed Central

    Janik-Moszant, Anna; Matyl, Aleksander; Rurańska, Iwona; Machowska-Majchrzak, Agnieszka; Kluczewska, Ewa; Szczepański, Tomasz

    2012-01-01

    Summary Background: Although the new intensive chemotherapeutic programs introduced recently into hematooncological therapies have led to a higher number of recoveries, persistent neutropenia favours the spread of severe infections, frequently fungal infections. Systemic fungal infections in patients treated for proliferative diseases of the hematopoietic system are characterised by a severe, progressing course and high morbidity. Case Reports: We present a case report that demonstrates the diagnostic problem of lesions in the central nervous system which developed following the fourth block of chemotherapy in an eight-year-old boy treated for acute myeloid leukaemia. The risk factors, high values of the inflammatory parameters and imaging results enabled us to diagnose a fungal infection of the central nervous system. Results: A fast improvement in the clinical condition of the patient after the applied antifungal therapy and the regression of lesions in the central nervous system shown in the imaging studies confirmed our final diagnosis. PMID:22802867

  6. Retinal Stimulation on Rabbit Using Complementary Metal Oxide Semiconductor Based Multichip Flexible Stimulator toward Retinal Prosthesis

    NASA Astrophysics Data System (ADS)

    Tokuda, Takashi; Asano, Ryosuke; Sugitani, Sachie; Taniyama, Mari; Terasawa, Yasuo; Nunoshita, Masahiro; Nakauchi, Kazuaki; Fujikado, Takashi; Tano, Yasuo; Ohta, Jun

    2008-04-01

    The Functionality of a complementary metal oxide semiconductor (CMOS) LSI-based, multichip flexible retinal stimulator was demonstrated in retinal stimulation experiments on rabbits. A 1×4-configured multichip stimulator was fabricated for application to experiments on animals. An experimental procedure including surgical operations was developed, and retinal stimulation was performed with the fabricated multichip stimulator. Neural responses on the visual cortex were successfully evoked by the fabricated stimulator. The stimulator is confirmed to be applicable to acute animal experiments.

  7. Comparison of Serum Cortisol and Testosterone Levels in Acute and Chronic Central Serous Chorioretinopathy

    PubMed Central

    Natung, Tanie

    2015-01-01

    Purpose To compare the levels of serum cortisol and testosterone in acute and chronic central serous chorio-retinopathy (CSC). Methods Serum cortisol and testosterone levels in 30 patients with either acute or chronic CSC were evaluated using chemiluminescent immunoassay. Results The mean age was 42.43 ± 6.37 years (range, 32 to 56 years). The mean 8:00 to 9.00 a.m. serum cortisol level was 12.61 ± 4.74 µg/dL (range, 6.58 to 27.42 µg/dL). The mean serum testosterone level was 5.88 ± 1.57 ng/dL (range, 2.81 to 9.94 ng/dL). The mean visual acuity was 20 / 65.07 ± 40.56 (range, 20 / 25 to 20 / 200). There was no statistically significant difference in the mean levels of serum cortisol and testosterone between the acute and chronic cases (p > 0.05), but there was a statistically significant difference in the mean presenting visual acuity in the two groups (p < 0.05). Conclusions All except one patient in the acute group had normal levels of serum cortisol. Testosterone levels were within the normal range in both the acute and chronic cases of CSC. There is unlikely to be any statistically significant difference in the mean levels of serum cortisol and testosterone between the acute and chronic cases, but there may be a statistically significant difference in the mean presenting visual acuity in these groups. PMID:26635454

  8. Current perspectives of herpesviral retinitis and choroiditis.

    PubMed

    Madhavan, H N; Priya, K; Biswas, J

    2004-10-01

    Vision-threatening viral retinitis are primarily caused by members of the herpesvirus family. The biology and molecular characterization of herpesviruses, clinical presentations of retinopathies, pathology and pathogenesis including the host responses, epidemiology and the laboratory methods of aetiological diagnosis of these diseases are described. Clinical syndromes are acute retinal necrosis (ARN), progressive outer retinal necrosis (PORN), cytomegalovirus (CMV) retinitis, multifocal choroiditis and serpiginous choroiditis besides other viral retinopathies. Herpes simplex virus (HSV) retinitis is more common in immunocompetent persons while varicella zoster virus (VZV) affects both immunocompetent and immunosuppressed patients equally. CMV retinitis is most common among patients with AIDS. The currently employed laboratory methods of antigen detection, virus isolation and antibody detection by enzyme linked immuno-sorbent assay (ELISA) have low sensitivity. Polymerase chain reaction (PCR) has increased the value of diagnosis due to its high clinical sensitivity and absolute specificity in detection of herpesviruses in intraocular specimens. PMID:16295367

  9. The progressive outer retinal necrosis syndrome.

    PubMed

    Holland, G N

    1994-01-01

    The progressive outer retinal necrosis (PORN) syndrome is a recently described clinical variant of necrotizing herpetic retinopathy in patients with the acquired immunodeficiency syndrome (AIDS). It is caused by varicellazoster virus infection of the retina. Its course and clinical features distinguish it from the acute retinal necrosis syndrome and CMV retinopathy. Early disease is characterized by multifocal deep retinal opacification. Lesions rapidly coalesce and progress to total retinal necrosis over a short period of time. Despite aggressive therapy with intravenous antivirial drugs, prognosis is poor; disease progression and/or recurrence is common, and the majority of patients develop no light perception vision. Total retinal detachments are common. Prophylaxis against retinal detachment using laser retinopexy has not been useful in most cases. PORN syndrome is an uncommon, but devastating complication of AIDS.

  10. Current perspectives of herpesviral retinitis and choroiditis.

    PubMed

    Madhavan, H N; Priya, K; Biswas, J

    2004-10-01

    Vision-threatening viral retinitis are primarily caused by members of the herpesvirus family. The biology and molecular characterization of herpesviruses, clinical presentations of retinopathies, pathology and pathogenesis including the host responses, epidemiology and the laboratory methods of aetiological diagnosis of these diseases are described. Clinical syndromes are acute retinal necrosis (ARN), progressive outer retinal necrosis (PORN), cytomegalovirus (CMV) retinitis, multifocal choroiditis and serpiginous choroiditis besides other viral retinopathies. Herpes simplex virus (HSV) retinitis is more common in immunocompetent persons while varicella zoster virus (VZV) affects both immunocompetent and immunosuppressed patients equally. CMV retinitis is most common among patients with AIDS. The currently employed laboratory methods of antigen detection, virus isolation and antibody detection by enzyme linked immuno-sorbent assay (ELISA) have low sensitivity. Polymerase chain reaction (PCR) has increased the value of diagnosis due to its high clinical sensitivity and absolute specificity in detection of herpesviruses in intraocular specimens.

  11. The progressive outer retinal necrosis syndrome.

    PubMed

    Holland, G N

    1994-01-01

    The progressive outer retinal necrosis (PORN) syndrome is a recently described clinical variant of necrotizing herpetic retinopathy in patients with the acquired immunodeficiency syndrome (AIDS). It is caused by varicellazoster virus infection of the retina. Its course and clinical features distinguish it from the acute retinal necrosis syndrome and CMV retinopathy. Early disease is characterized by multifocal deep retinal opacification. Lesions rapidly coalesce and progress to total retinal necrosis over a short period of time. Despite aggressive therapy with intravenous antivirial drugs, prognosis is poor; disease progression and/or recurrence is common, and the majority of patients develop no light perception vision. Total retinal detachments are common. Prophylaxis against retinal detachment using laser retinopexy has not been useful in most cases. PORN syndrome is an uncommon, but devastating complication of AIDS. PMID:7852023

  12. Retinal abnormalities in β-thalassemia major.

    PubMed

    Bhoiwala, Devang L; Dunaief, Joshua L

    2016-01-01

    Patients with beta (β)-thalassemia (β-TM: β-thalassemia major, β-TI: β-thalassemia intermedia) have a variety of complications that may affect all organs, including the eye. Ocular abnormalities include retinal pigment epithelial degeneration, angioid streaks, venous tortuosity, night blindness, visual field defects, decreased visual acuity, color vision abnormalities, and acute visual loss. Patients with β-thalassemia major are transfusion dependent and require iron chelation therapy to survive. Retinal degeneration may result from either retinal iron accumulation from transfusion-induced iron overload or retinal toxicity induced by iron chelation therapy. Some who were never treated with iron chelation therapy exhibited retinopathy, and others receiving iron chelation therapy had chelator-induced retinopathy. We will focus on retinal abnormalities present in individuals with β-thalassemia major viewed in light of new findings on the mechanisms and manifestations of retinal iron toxicity. PMID:26325202

  13. Functional biomarkers for the acute effects of alcohol on the central nervous system in healthy volunteers

    PubMed Central

    Zoethout, Remco W M; Delgado, Wilson L; Ippel, Annelies E; Dahan, Albert; van Gerven, Joop M A

    2011-01-01

    The central nervous system (CNS) effects of acute alcohol administration have been frequently assessed. Such studies often use a wide range of methods to study each of these effects. Unfortunately, the sensitivity of these tests has not completely been ascertained. A literature search was performed to recognize the most useful tests (or biomarkers) for identifying the acute CNS effects of alcohol in healthy volunteers. All tests were grouped in clusters and functional domains. Afterwards, the effect of alcohol administration on these tests was scored as improvement, impairment or as no effect. Furthermore, dose–response relationships were established. A total number of 218 studies, describing 342 different tests (or test variants) were evaluated. Alcohol affected a wide range of CNS domains. Divided attention, focused attention, visuo-motor control and scales of feeling high and of subjective drug effects were identified as the most sensitive functional biomarkers for the acute CNS effects of alcohol. The large number of CNS tests that are used to determine the effects of alcohol interferes with the identification of the most sensitive ones and of drug–response relationships. Our results may be helpful in selecting rational biomarkers for studies investigating the acute CNS effects of alcohol or for future alcohol- interaction studies. PMID:21284693

  14. [Autochthonous acute viral and bacterial infections of the central nervous system (meningitis and encephalitis)].

    PubMed

    Pérez-Ruiz, Mercedes; Vicente, Diego; Navarro-Marí, José María

    2008-07-01

    Rapid diagnosis of acute viral and bacterial infections of the central nervous system (meningitis and encephalitis) is highly important for the clinical management of the patient and helps to establish early therapy that may solve life-threatening situations, to avoid unnecessary empirical treatments, to reduce hospital stay, and to facilitate appropriate interventions in the context of public health. Molecular techniques, especially real-time polymerase chain reaction, have become the fastest and most sensitive diagnostic procedures for autochthonous viral meningitis and encephalitis, and their role is becoming increasingly important for the diagnosis and control of most frequent acute bacterial meningitides. Automatic and closed systems may encourage the widespread and systematic use of molecular techniques for the diagnosis of these neurological syndromes in most laboratories.

  15. The acute effects of smokeless tobacco on central aortic blood pressure and wave reflection characteristics.

    PubMed

    Martin, Jeffrey S; Beck, Darren T; Gurovich, Alvaro N; Braith, Randy W

    2010-10-01

    The main objectives of this study were to examine the acute effect of a single dose of smokeless tobacco (ST) on central aortic blood pressure and wave reflection characteristics. Fifteen apparently healthy male subjects (aged 30.6 ± 6.2 y) were given a 2.5 g oral dose of ST after baseline measurements were recorded. Pulse wave analysis using radial artery applanation tonometry was performed in triplicate at baseline (0 min) and at 10-min intervals during (10, 20 and 30 min) and after (40, 50 and 60 min) ST use. An acute dose of ST was associated with a significant increase in heart rate (HR), central aortic systolic and diastolic blood pressure, peripheral brachial systolic and diastolic blood pressure, and aortic augmentation index normalized to a fixed heart rate of 75 bpm (AIx@75). Furthermore, ejection duration and round trip travel time of the reflected pressure wave (Δt(p)) were significantly decreased as a result of one time ST use. As a result of changes in aortic pressure wave reflection characteristics, there was a significant increase in wasted left ventricular pressure energy (LVE(w)) and the tension-time index (TTI) as a result of ST use. In conclusion, one time use of ST elicits significant transient increases in HR, central aortic pressures, AIx@75, the TTI and LVE(w). Chronic users subjected to decades of elevated central pressures and left ventricular work may have an increased cardiovascular risk as central aortic pressures are even more strongly related to cardiovascular outcomes than peripheral blood pressures.

  16. Interleukin-1 beta-induced disruption of the retinal vascular barrier of the central nervous system is mediated through leukocyte recruitment and histamine.

    PubMed Central

    Bamforth, S. D.; Lightman, S. L.; Greenwood, J.

    1997-01-01

    The vascular barriers of the central nervous system form a selective cellular interface between the blood and the neural parenchyma and restrict the transfer of both molecules and hematogenous cells. During immune-mediated diseases, leukocyte infiltration becomes dramatically up-regulated and the permeability of these barriers increases, leading to edema formation. The etiology of this damage remains largely unresolved although inflammatory cytokines have been implicated in the process. The effect of the proinflammatory cytokine interleukin (IL)-1 beta on the integrity of the rat blood-retinal barrier (BRB) was investigated up to 14 days after an intravitreal injection. The permeability of the BRB was evaluated quantitatively using the low molecular weight tracer [14C]mannitol. After IL-1 beta administration, a biphasic opening of the BRB to [14C]mannitol was recorded, peaking at 4 to 8 hours and 24 to 48 hours post-injection (PI). The early disruption coincided with the appearance of both polymorphonuclear and mononuclear leukocytes within the retina. By 12 hours PI, BRB permeability had returned to control values despite a continued increase in the number of infiltrating leukocytes. The second, more pronounced increase in barrier permeability detected at 24 to 48 hours PI corresponded with maximal leukocyte infiltration. Barrier dysfunction had resolved by 72 hours, and by 7 days the leukocyte infiltrate had disappeared. The IL-1 beta-induced increase in permeability could be completely abrogated at 4 and 24 hours PI by treating the animals with the histamine H2-receptor antagonist ranitidine, which also reduced leukocyte infiltration by 47.2%. The ability of histamine to disrupt the BRB was demonstrated by intravitreal and intravascular administration, which caused a rapid and significant increase in BRB permeability. Treatment of the animals with the cyclo-oxygenase inhibitor indomethacin had no effect on IL-1 beta-induced disruption of the BRB at 4 hours PI

  17. [Primary Central Nervous System Post-Transplant Lymphoproliferative Disorder in a Patient with Acute Lymphocytic Leukemia].

    PubMed

    Azuma, Yoshiko; Nakaya, Aya; Fujita, Shinya; Hotta, Masaaki; Fujita, Yukie; Yoshimura, Hideaki; Nakanishi, Takahisa; Satake, Atsushi; Ito, Tomoki; Ishii, Kazuyoshi; Nomura, Shosaku

    2015-08-01

    A 27-year-old woman with acute lymphocytic leukemia, who underwent allogeneic hematopoietic stem cell transplantation, complained of nausea and blurred vision 288 days after the transplantation. Intracranial tumors were identified on brain MRI. She received whole brain radiation after open biopsy, but she died. The tumors had characteristics of diffuse large B cell lymphoma, and she was finally diagnosed with primary central nervous system post-transplant lymphoproliferative disorder. This disease is rare and has a poor outcome. Therefore, accumulation of cases and establishment of treatments for this condition are urgently needed.

  18. Retinal vascular changes are a marker for cerebral vascular diseases

    PubMed Central

    Moss, Heather E.

    2016-01-01

    The retinal circulation is a potential marker of cerebral vascular disease because it shares origin and drainage with the intracranial circulation and because it can be directly visualized using ophthalmoscopy. Cross sectional and cohort studies have demonstrated associations between chronic retinal and cerebral vascular disease, acute retinal and cerebral vascular disease and chronic retinal vascular disease and acute cerebral vascular disease. In particular, certain qualitative features of retinopathy, retinal artery occlusion and increased retinal vein caliber are associated with concurrent and future cerebrovascular events. These associations persist after accounting for confounding variables known to be disease-causing in both circulations, which supports the potential use of retinal vasculature findings to stratify individuals with regards to cerebral vascular disease risk. PMID:26008809

  19. Microsystems Technology for Retinal Implants

    NASA Astrophysics Data System (ADS)

    Weiland, James

    2005-03-01

    The retinal prosthesis is targeted to treat age-related macular degeneration, retinitis pigmentosa, and other outer retinal degenerations. Simulations of artificial vision have predicted that 600-1000 individual pixels will be needed if a retinal prosthesis is to restore function such as reading large print and face recognition. An implantable device with this many electrode contacts will require microsystems technology as part of its design. An implantable retinal prosthesis will consist of several subsystems including an electrode array and hermetic packaging. Microsystems and microtechnology approaches are being investigated as possible solutions for these design problems. Flexible polydimethylsiloxane (PDMS) substrate electrode arrays and silicon micromachined electrode arrays are under development. Inactive PDMS electrodes have been implanted in 3 dogs to assess mechanical biocompatibility. 3 dogs were followed for 6 months. The implanted was securely fastened to the retina with a single retinal tack. No post-operative complications were evident. The array remained within 100 microns of the retinal surface. Histological evaluation showed a well preserved retina underneath the electrode array. A silicon device with electrodes suspended on micromachined springs has been implanted in 4 dogs (2 acute implants, 2 chronic implants). The device, though large, could be inserted into the eye and positioned on the retina. Histological analysis of the retina from the spring electrode implants showed that spring mounted posts penetrated the retina, thus the device will be redesigned to reduce the strength of the springs. These initial implants will provide information for the designers to make the next generation silicon device. We conclude that microsystems technology has the potential to make possible a retinal prosthesis with 1000 individual contacts in close proximity to the retina.

  20. The central role of hypothalamic inflammation in the acute illness response and cachexia.

    PubMed

    Burfeind, Kevin G; Michaelis, Katherine A; Marks, Daniel L

    2016-06-01

    When challenged with a variety of inflammatory threats, multiple systems across the body undergo physiological responses to promote defense and survival. The constellation of fever, anorexia, and fatigue is known as the acute illness response, and represents an adaptive behavioral and physiological reaction to stimuli such as infection. On the other end of the spectrum, cachexia is a deadly and clinically challenging syndrome involving anorexia, fatigue, and muscle wasting. Both of these processes are governed by inflammatory mediators including cytokines, chemokines, and immune cells. Though the effects of cachexia can be partially explained by direct effects of disease processes on wasting tissues, a growing body of evidence shows the central nervous system (CNS) also plays an essential mechanistic role in cachexia. In the context of inflammatory stress, the hypothalamus integrates signals from peripheral systems, which it translates into neuroendocrine perturbations, altered neuronal signaling, and global metabolic derangements. Therefore, we will discuss how hypothalamic inflammation is an essential driver of both the acute illness response and cachexia, and why this organ is uniquely equipped to generate and maintain chronic inflammation. First, we will focus on the role of the hypothalamus in acute responses to dietary and infectious stimuli. Next, we will discuss the role of cytokines in driving homeostatic disequilibrium, resulting in muscle wasting, anorexia, and weight loss. Finally, we will address mechanisms and mediators of chronic hypothalamic inflammation, including endothelial cells, chemokines, and peripheral leukocytes. PMID:26541482

  1. The central role of hypothalamic inflammation in the acute illness response and cachexia.

    PubMed

    Burfeind, Kevin G; Michaelis, Katherine A; Marks, Daniel L

    2016-06-01

    When challenged with a variety of inflammatory threats, multiple systems across the body undergo physiological responses to promote defense and survival. The constellation of fever, anorexia, and fatigue is known as the acute illness response, and represents an adaptive behavioral and physiological reaction to stimuli such as infection. On the other end of the spectrum, cachexia is a deadly and clinically challenging syndrome involving anorexia, fatigue, and muscle wasting. Both of these processes are governed by inflammatory mediators including cytokines, chemokines, and immune cells. Though the effects of cachexia can be partially explained by direct effects of disease processes on wasting tissues, a growing body of evidence shows the central nervous system (CNS) also plays an essential mechanistic role in cachexia. In the context of inflammatory stress, the hypothalamus integrates signals from peripheral systems, which it translates into neuroendocrine perturbations, altered neuronal signaling, and global metabolic derangements. Therefore, we will discuss how hypothalamic inflammation is an essential driver of both the acute illness response and cachexia, and why this organ is uniquely equipped to generate and maintain chronic inflammation. First, we will focus on the role of the hypothalamus in acute responses to dietary and infectious stimuli. Next, we will discuss the role of cytokines in driving homeostatic disequilibrium, resulting in muscle wasting, anorexia, and weight loss. Finally, we will address mechanisms and mediators of chronic hypothalamic inflammation, including endothelial cells, chemokines, and peripheral leukocytes.

  2. Genetic networks controlling retinal injury

    PubMed Central

    Vazquez-Chona, Felix R.; Khan, Amna N.; Chan, Chun K.; Moore, Anthony N.; Dash, Pramod K.; Hernandez, M. Rosario; Lu, Lu; Chesler, Elissa J.; Manly, Kenneth F.; Williams, Robert W.; Geisert, Eldon E.

    2010-01-01

    Purpose The present study defines genomic loci underlying coordinate changes in gene expression following retinal injury. Methods A group of acute phase genes expressed in diverse nervous system tissues was defined by combining microarray results from injury studies from rat retina, brain, and spinal cord. Genomic loci regulating the brain expression of acute phase genes were identified using a panel of BXD recombinant inbred (RI) mouse strains. Candidate upstream regulators within a locus were defined using single nucleotide polymorphism databases and promoter motif databases. Results The acute phase response of rat retina, brain, and spinal cord was dominated by transcription factors. Three genomic loci control transcript expression of acute phase genes in brains of BXD RI mouse strains. One locus was identified on chromosome 12 and was highly correlated with the expression of classic acute phase genes. Within the locus we identified the inhibitor of DNA binding 2 (Id2) as a candidate upstream regulator. Id2 was upregulated as an acute phase transcript in injury models of rat retina, brain, and spinal cord. Conclusions We defined a group of transcriptional changes associated with the retinal acute injury response. Using genetic linkage analysis of natural transcript variation, we identified regulatory loci and candidate regulators that control transcript levels of acute phase genes. PMID:16288200

  3. A Randomized Trial Comparing the Efficacy and Safety of Intravitreal Triamcinolone With Observation to Treat Vision Loss Associated With Macular Edema Secondary to Central Retinal Vein Occlusion

    PubMed Central

    Ip, Michael S.; Scott, Ingrid U.; VanVeldhuisen, Paul C.; Oden, Neal L.; Blodi, Barbara A.; Fisher, Marian; Singerman, Lawrence J.; Tolentino, Michael; Chan, Clement K.; Gonzalez, Victor H.

    2009-01-01

    Objective: To compare the efficacy and safety of 1-mg and 4-mg doses of preservative-free intravitreal triamcinolone with observation for eyes with vision loss associated with macular edema secondary to perfused central retinal vein occlusion (CRVO). Methods: Multicenter, randomized, clinical trial of 271 participants. Main Outcome Measure: Gain in visual acuity letter score of 15 or more from baseline to month 12. Results: Seven percent, 27%, and 26% of participants achieved the primary outcome in the observation, 1-mg, and 4-mg groups, respectively. The odds of achieving the primary outcome were 5.0 times greater in the 1-mg group than the observation group (odds ratio [OR],5.0; 95% confidence interval [CI], 1.8-14.1; P=.001) and 5.0 times greater in 4-mg group than the observation group (OR,5.0; 95% CI, 1.8-14.4; P=.001); there was no difference identified between the 1-mg and 4-mg groups (OR, 1.0; 95% CI, 0.5-2.1; P=.97). The rates of elevated intraocular pressure and cataract were similar for the observation and 1-mg groups, but higher in the 4-mg group. Conclusions: Intravitreal triamcinolone is superior to observation for treating vision loss associated with macular edema secondary to CRVO in patients who have characteristics similar to those in the SCORE-CRVO trial. The 1-mg dose has a safety profile superior to that of the 4-mg dose. Application to Clinical Practice: Intravitreal triamcinolone in a 1-mg dose, following the retreatment criteria applied in the SCORE Study, should be considered for up to 1 year, and possibly 2 years, for patients with characteristics similar to those in the SCORE-CRVO trial. Trial Registration: clinicaltrials.gov Identifier: NCT00105027 PMID:19752419

  4. Do growth-stimulated retinal ganglion cell axons find their central targets after optic nerve injury? New insights by three-dimensional imaging of the visual pathway.

    PubMed

    Diekmann, Heike; Leibinger, Marco; Fischer, Dietmar

    2013-10-01

    Retinal ganglion cells (RGCs) do not normally regenerate injured axons. However, several strategies to transform RGCs into a potent regenerative state have been developed in recent years. Intravitreal CNTF application combined with conditional PTEN and SOCS3 deletion or zymosan-induced inflammatory stimulation together with cAMP analogue injection and PTEN-deletion in RGCs induce long-distance regeneration into the optic nerve of adult mice. A recent paper by the Benowitz group (de Lima et al.) claimed that the latter treatment enables full-length regeneration, with axons correctly navigating to their central target zones and partial recovery of visual behaviors. To gain a more detailed view of the extent and the trajectories of regenerating axons, Luo et al. applied a tissue clearing method and fluorescent microscopy to allow the tracing of naïve and regenerating RGC axons in whole ON and all the way to their brain targets. Using this approach, the authors found comparable axon regeneration in the optic nerve after both above-mentioned experimental treatments. Regeneration was accompanied by prevalent aberrant axon growth in the optic nerve and significant axonal misguidance at the optic chiasm. Less than 120 axons per animal reached the optic chiasm and only few entered the correct optic tract. Importantly, no axons reached visual targets in the olivary pretectal nucleus, the lateral geniculate nucleus or the superior colliculus, thereby contradicting and challenging previous claims by the Benowitz group. The data provided by Luo et al. rather suggest that potent stimulation of axonal growth per se is insufficient to achieve functional recovery and underscore the need to investigate regeneration-relevant axon guidance mechanisms in the mature visual system. PMID:23816572

  5. Acute, subacute and chronic effects of central neuropeptide Y on energy balance in rats.

    PubMed

    Székely, M; Pétervári, E; Pákai, E; Hummel, Z; Szelényi, Z

    2005-04-01

    Central neuropeptide Y (NPY) injection has been reported to cause hyperphagia and in some cases also hypometabolism or hypothermia. Chronic central administration induced a moderate rise of short duration in body weight, without consistent metabolic/thermal changes. In the present studies the acute and subsequent subacute ingestive and metabolic/thermal changes were studied following intracerebroventricular (i.c.v.) injections of NPY in cold-adapted and non-adapted rats, or the corresponding chronic changes following i.c.v. NPY infusion. Besides confirming basic earlier data, we demonstrated novel findings: a temporal relationship for the orexigenic and metabolic/thermal effects, and differences of coordination in acute/subacute/chronic phases or states. The acute phase (30-60 min after injection) was anabolic: coordinated hyperphagia and hypometabolism/hypothermia. NPY evoked a hypothermia by suppressing any (hyper)metabolism in excess of basal metabolic rate, without enhancing heat loss. Thus, acute hypothermia was observed in sub-thermoneutral but not thermoneutral environments. The subsequent subacute catabolic phase exhibited opposite effects: slight increase in metabolic rate, rise in body temperature, reaching a plateau within 3-4 h after injection -- this was maintained for at least 24 h; meanwhile the food intake decreased and the normal daily weight gain stopped. This rebound is only indirectly related to NPY. Chronic (7-day long) i.c.v. NPY infusion induced an anabolic phase for 2-3 days, followed by a catabolic phase and fever, despite continued infusion. In cold-adaptation environment the primary metabolic effect of the infusion induced a moderate hypothermia with lower daytime nadirs and nocturnal peaks of the circadian temperature rhythm, while at near-thermoneutral environments in non-adapted rats the infusion attenuated only the nocturnal temperature rise by suppressing night-time hypermetabolism. Further finding is that in cold-adapted animals

  6. Acute eosinophilic myocarditis with dramatic response to steroid therapy: the central role of echocardiography in diagnosis and follow-up.

    PubMed

    Eppenberger, Manuela; Hack, Dietrich; Ammann, Peter; Rickli, Hans; Maeder, Micha T

    2013-01-01

    Acute eosinophilic myocarditis is a rare cause of acute heart failure. We present the case of a 32-year-old woman who had presumptive eosinophilic myocarditis as part of a generalized hypersensitivity reaction (Drug Rash with Eosinophilia and Systemic Symptoms [DRESS] syndrome) that exhibited a dramatic response to steroid therapy. We highlight the central role of 2-dimensional and tissue-Doppler echocardiography in the diagnosis of myocarditis and the serial evaluation of left ventricular systolic and diastolic function in this setting.

  7. Retinal Detachment Vision Simulator

    MedlinePlus

    ... Retina Treatment Retinal Detachment Vision Simulator Retinal Detachment Vision Simulator Mar. 01, 2016 How does a detached or torn retina affect your vision? If a retinal tear is occurring, you may ...

  8. Retinal holes.

    PubMed

    Foos, R Y

    1978-09-01

    Holes of the peripheral retina, defined as full-thickness breaks of trophic origin with no associated flap or free operculum, were found in 136 (2.4%) eyes from 2,800 autopsied subjects. Primary retinal holes (those with no indication of a proximal causative lesion and with no lattice degeneration in either eye) occurred in only eight of the 5,600 eyes studied; all were unilateral, single, less than 0.25 disk diameter in size, within the basal zone, and in eyes from elderly subjects. Secondary holes were found in 128 (2.3%) of eyes and of these, lattice degeneration was the most common cause (103). Other lesions complicated by hole formation included zonular traction tufts (10), chorioretinitis (9), meridional folds (3), and pavingstone degeneration (2). Retinal holes in surgically aphakic eyes did not differ qualitatively or quantitatively from those in age-matched phakic eyes.

  9. [Retinal vein occlusion in a young patient].

    PubMed

    Zemba, Mihail; Ochinciuc, Uliana; Sarbu, Laura; Avram, Corina; Camburu, Raluca; Stamate, Alina

    2013-01-01

    We present a case report of a 27 years old pacient with central retinal vein occlussion and macular edema. The pacient has a significant reduction of the macular aedema with complete recovery of vision after the treatment.

  10. Molecular Analysis of Central Nervous System Disease Spectrum in Childhood Acute Lymphoblastic Leukemia

    PubMed Central

    Hicks, Chindo; Sitthi-Amorn, Jitsuda; Douglas, Jessica; Ramani, Ritika; Miele, Lucio; Vijayakumar, Vani; Karlson, Cynthia; Chipeta, James; Megason, Gail

    2016-01-01

    Treatment of the central nervous system (CNS) is an essential therapeutic component in childhood acute lymphoblastic leukemia (ALL). The goal of this study was to identify molecular signatures distinguishing patients with CNS disease from those without the disease in pediatric patients with ALL. We analyzed gene expression data from 207 pediatric patients with ALL. Patients without CNS were classified as CNS1, while those with mild and advanced CNS disease were classified as CNS2 and CNS3, respectively. We compared gene expression levels among the three disease classes. We identified gene signatures distinguishing the three disease classes. Pathway analysis revealed molecular networks and biological pathways dysregulated in response to CNS disease involvement. The identified pathways included the ILK, WNT, B-cell receptor, AMPK, ERK5, and JAK signaling pathways. The results demonstrate that transcription profiling could be used to stratify patients to guide therapeutic decision-making in pediatric ALL. PMID:26997880

  11. Central autonomic network mediates cardiovascular responses to acute inflammation: Relevance to increased cardiovascular risk in depression?

    PubMed Central

    Harrison, Neil A.; Cooper, Ella; Voon, Valerie; Miles, Ken; Critchley, Hugo D.

    2013-01-01

    Inflammation is a risk factor for both depression and cardiovascular disease. Depressed mood is also a cardiovascular risk factor. To date, research into mechanisms through which inflammation impacts cardiovascular health rarely takes into account central effects on autonomic cardiovascular control, instead emphasizing direct effects of peripheral inflammatory responses on endothelial reactivity and myocardial function. However, brain responses to inflammation engage neural systems for motivational and homeostatic control and are expressed through depressed mood state and changes in autonomic cardiovascular regulation. Here we combined an inflammatory challenge, known to evoke an acute reduction in mood, with neuroimaging to identify the functional brain substrates underlying potentially detrimental changes in autonomic cardiovascular control. We first demonstrated that alterations in the balance of low to high frequency (LF/HF) changes in heart rate variability (a measure of baroreflex sensitivity) could account for some of the inflammation-evoked changes in diastolic blood pressure, indicating a central (rather than solely local endothelial) origin. Accompanying alterations in regional brain metabolism (measured using 18FDG-PET) were analysed to localise central mechanisms of inflammation-induced changes in cardiovascular state: three discrete regions previously implicated in stressor-evoked blood pressure reactivity, the dorsal anterior and posterior cingulate and pons, strongly mediated the relationship between inflammation and blood pressure. Moreover, activity changes within each region predicted the inflammation-induced shift in LF/HF balance. These data are consistent with a centrally-driven component originating within brain areas supporting stressor evoked blood pressure reactivity. Together our findings highlight mechanisms binding psychological and physiological well-being and their perturbation by peripheral inflammation. PMID:23416033

  12. Evidence Report: Risk of Acute and Late Central Nervous System Effects from Radiation Exposure

    NASA Technical Reports Server (NTRS)

    Nelson, Gregory A.; Simonsen, Lisa; Huff, Janice L.

    2016-01-01

    Possible acute and late risks to the central nervous system (CNS) from galactic cosmic rays (GCR) and solar particle events (SPE) are concerns for human exploration of space. Acute CNS risks may include: altered cognitive function, reduced motor function, and behavioral changes, all of which may affect performance and human health. Late CNS risks may include neurological disorders such as Alzheimer's disease (AD), dementia and premature aging. Although detrimental CNS changes are observed in humans treated with high-dose radiation (e.g., gamma rays and 9 protons) for cancer and are supported by experimental evidence showing neurocognitive and behavioral effects in animal models, the significance of these results on the morbidity to astronauts has not been elucidated. There is a lack of human epidemiology data on which to base CNS risk estimates; therefore, risk projection based on scaling to human data, as done for cancer risk, is not possible for CNS risks. Research specific to the spaceflight environment using animal and cell models must be compiled to quantify the magnitude of CNS changes in order to estimate this risk and to establish validity of the current permissible exposure limits (PELs). In addition, the impact of radiation exposure in combination with individual sensitivity or other space flight factors, as well as assessment of the need for biological/pharmaceutical countermeasures, will be considered after further definition of CNS risk occurs.

  13. Evaluation of the acute cardiac and central nervous system effects of the fluorocarbon trifluoromethane in baboons

    SciTech Connect

    Branch, C.A.; Goldberg, D.A.; Ewing, J.R.; Butt, S.S.; Gayner, J.; Fagan, S.C.

    1994-12-31

    The gaseous fluorocarbon trifluoromethane has recently been investigated for its potential as an in vivo gaseous indicator for nuclear magnetic resonance studies of brain perfusion. Trifluoromethane may also have significant value as a replacement for chlorofluorocarbon fire retardants. Because of possible species-specific cardiotoxic and anesthetic properties, the toxicological evaluation of trifluoromethane in primates (Papio anubis) is necessary prior to its evaluation in humans. We report the acute cardiac and central nervous system effects of trifluoromethane in eight anesthetized baboons. A dose-response effect was established for respiratory rate, electroencephalogram, and cardiac sinus rate, which exhibited a stepwise decrease from 10% trifluoromethane. No spontaneous arrhythmias were noted, and arterial blood pressure remained unchanged at any inspired level. Intravenous epinephrine infusions (1 {mu}g/kg) induced transient cardiac arrhythmia in 1 animal only at 70% FC-23 (v/v) trifluoromethane. Trifluoromethane appears to induce mild dose-related physiological changes at inspired levels of 30% or more, indicative of an anesthetic effect. These data suggest that trifluoromethane may be safe to use in humans, without significant adverse acute effects, at an inspired level of 30%. 23 refs., 3 figs., 3 tabs.

  14. [Novel mechanism for retinal vascular diseases].

    PubMed

    Suzuma, Kiyoshi

    2015-03-01

    I. A new therapeutic target for diabetic retinopathy. Recent reports state that succinate may be an independent retinal angiogenic factor. We evaluated concentrations in vitreous from proliferative diabetic retinopathy (PDR), and found that succinate increased significantly in PDR. Interestingly, levels of succinate from bevacizumab-pre-injected PDR were normal, suggesting that vascular endothelial growth factor (VEGF) had a positive feedback mechanism for succinate since succinate was previously reported to induce VEGF. II. A new understanding of central retinal vein occlusion (CRVO). We evaluated retinal blood flow velocity with laser speckle flowgraphy (LSFG) made in Japan, and found that cases in which both macular edema and retinal blood flow velocity improved after anti-VEGF therapy had better prognosis. In ischemic CRVO at final visit, mean retinal blood velocity was less than 50% of fellow eyes after 1st anti-VEGF therapy, suggesting that those cases might have poor prognosis. LSFG is useful for evaluation and decision in CRVO treatment. III. From exploration for mechanism in retinal vascular diseases to re-vascularization therapy. The standard treatment for retinal non-perfusion area is scatter laser photocoagulation, which is both invasive of the peripheral retina and may prove destructive. Re-vascularization is an ideal strategy for treatment of retinal non-perfusion area. To develop a new methods for re-vascularization in retinal non-perfusion area, we have designed experiments using a retina without vasculature differentiated from induced pluripotent stem(iPS) cells.

  15. Clinical research of fenofibrate and spironolactone for acute central serous chorioretinopathy

    PubMed Central

    Chai, Yong; Liu, Rong-Qiang; Yi, Jing-Lin; Ye, Ling-Hong; Zou, Jing; Jiang, Nan; Shao, Yi

    2016-01-01

    AIM To compare the effectiveness of combined fenofibrate and spironolactone with fenofibrate alone for treatment of central serous chorioretinopathy (CSCR). METHODS Totally 60 patients (60 eyes) with a history of acute CSCR were randomed into two groups: group A with combination of fenofibrate (200 mg) and spironolactone (100 mg), and group B with only fenofibrate (200 mg). They were taken half an hour before meals and once per day for 8wk. The changes of the visual acuity, subjective symptom, ocular surface disease index (OSDI), the tear film and optical coherence tomography were observed at 2, 4, 6, and 8wk before and after treatment. RESULTS The best corrected visual acuity (BCVA, logMAR) was improved to 0.22 and 0.27 after treatment from baseline of 0.35 and 0.36 in groups A and B (P<0.05), respectively. After 8wk treatment, the central subfield thickness (CST), and subretinal fluid volumn (SFV) decreased significantly to 49.5% and 78.8% in group A and 37.0% and 57.2% in group B. There were significant differences of CST and SFV in both groups (all P<0.05). CONCLUSION Fenofibrate combined with spironolactone may have more clinical efficacy in the treatment of CSCR than fenofibrate only. PMID:27803862

  16. Fluorosilicone oil in the treatment of retinal detachment.

    PubMed Central

    Gremillion, C M; Peyman, G A; Liu, K R; Naguib, K S

    1990-01-01

    We evaluated the use of a heavier-than-water fluorinated silicone oil in the treatment of 30 selected cases of complicated retinal detachment from January 1988 to July 1989. Proliferative vitreoretinopathy grade C-2 or greater accounted for 19 cases, proliferative diabetic retinopathy with traction detachment for two cases, giant retinal tears five, ruptured globe with retinal detachment two, massive choroidal effusion with retinal detachment one, and acute retinal necrosis with retinal detachment one. Initial retinal reattachment was achieved in all cases. Complications included redetachment seven (23%), cataract six (75% of phakic patients), raised intraocular pressure four (13%), hypotony four (13%), keratopathy three (10%), uveitis-synechia formation three (10%), phthisis two (3%), choroidal haemorrhage one (3%), and vitreous haemorrhage one (3%). Postoperative visual acuities with at least six months' follow-up range from no light perception to 20/50, with seven patients (23%) 20/400 or better. Images PMID:2223698

  17. Fluorosilicone oil in the treatment of retinal detachment.

    PubMed

    Gremillion, C M; Peyman, G A; Liu, K R; Naguib, K S

    1990-11-01

    We evaluated the use of a heavier-than-water fluorinated silicone oil in the treatment of 30 selected cases of complicated retinal detachment from January 1988 to July 1989. Proliferative vitreoretinopathy grade C-2 or greater accounted for 19 cases, proliferative diabetic retinopathy with traction detachment for two cases, giant retinal tears five, ruptured globe with retinal detachment two, massive choroidal effusion with retinal detachment one, and acute retinal necrosis with retinal detachment one. Initial retinal reattachment was achieved in all cases. Complications included redetachment seven (23%), cataract six (75% of phakic patients), raised intraocular pressure four (13%), hypotony four (13%), keratopathy three (10%), uveitis-synechia formation three (10%), phthisis two (3%), choroidal haemorrhage one (3%), and vitreous haemorrhage one (3%). Postoperative visual acuities with at least six months' follow-up range from no light perception to 20/50, with seven patients (23%) 20/400 or better.

  18. Two long-lasting central respiratory responses following acute hypoxia in glomectomized cats.

    PubMed

    Gallman, E A; Millhorn, D E

    1988-01-01

    1. Central respiratory response to acute (10 min) hypoxia, as measured by phrenic nerve activity, was determined in peripheral chemo-denervated cats. 2. Hypoxia was induced by ventilating cats for 10 min at reduced inspired oxygen levels (inspired O2 fraction, FI,O2 = 0.06-0.15). The degree of hypoxaemia was determined from an arterial blood sample and ranged from 'severe' (arterial O2 pressure, Pa,O2 less than 26 Torr) to 'mild' (Pa,O2 greater than 35 Torr). The respiratory response was monitored for 1 h following return to ventilation with 100% oxygen. 3. The results confirmed the finding of prolonged (greater than 60 min) inhibition of respiration upon return to hyperoxic conditions following severe hypoxia, as reported previously (Millhorn, Eldridge, Kiley & Waldrop, 1984). A new finding was a long-lasting (greater than 60 min) facilitation of respiration following exposure to less severe (Pa,O2 greater than 35 Torr) hypoxia. 4. Medullary extracellular fluid pH was measured in six cats. Changes in pH could not explain either the prolonged inhibition following severe hypoxia or the long-lasting facilitation observed following mild hypoxia. 5. Ablation studies were performed in order to determine the locations of the neuronal substrates for the inhibitory and facilitatory mechanisms. The results of this series of experiments indicate that the mesencephalon is necessary for activation of the inhibitory mechanism, while the facilitatory mechanism requires the presence of higher brain structures, notably the diencephalon. 6. Following removal of the diencephalon, the inhibitory response was seen following even mild hypoxic insults, i.e. those shown to produce facilitation in animals with intact brains. In the absence of the mesencephalon, neither prolonged inhibition nor prolonged facilitation could be produced following hypoxia. 7. It is proposed that there are two centrally mediated long-lasting responses to acute hypoxia. Facilitation is seen following mild

  19. Hickman to central venous catheter: A case of difficult venous access in a child suffering from acute lymphoblastic leukemia

    PubMed Central

    Chakraborty, Arunangshu; Agrawal, Sanjit; Datta, Taniya; Mitra, Suparna; Khemka, Rakhi

    2016-01-01

    Chemotherapy in children suffering from cancer usually requires placement of an indwelling central venous catheter (CVC). A child may need to undergo repeated procedures because of infection and occlusion of previous access devices. We present a case of CVC insertion in a child suffering from acute lymphoblastic leukemia where an innovative technique was employed.

  20. Hickman to central venous catheter: A case of difficult venous access in a child suffering from acute lymphoblastic leukemia

    PubMed Central

    Chakraborty, Arunangshu; Agrawal, Sanjit; Datta, Taniya; Mitra, Suparna; Khemka, Rakhi

    2016-01-01

    Chemotherapy in children suffering from cancer usually requires placement of an indwelling central venous catheter (CVC). A child may need to undergo repeated procedures because of infection and occlusion of previous access devices. We present a case of CVC insertion in a child suffering from acute lymphoblastic leukemia where an innovative technique was employed. PMID:27695218

  1. Is the outcome in acute aortic dissection type A influenced by of femoral versus central cannulation?

    PubMed Central

    Bucsky, Bence S.; Richardt, Doreen; Petersen, Michael; Sievers, Hans H.

    2016-01-01

    Background The purpose of this study was to evaluate the single-center experience in initial femoral versus central cannulation of the extracorporeal circulation for acute aortic dissection type A (AADA). Methods Between January 2003 and December 2015, 235 patients underwent repair of AADA. All patients were evaluated for the type of arterial cannulation (femoral vs. central) for initial bypass. Demographic data and outcome parameters were accessed. Results One hundred and twenty seven (54.0%) were initially cannulated in the central aortic vessels (ascending aorta or subclavian/axillary artery) and 108 (46.0%) in the femoral artery. Patients were comparable between age (62.4±14.4 vs. 62.9±14.4 years, P=0.805), gender (male, 62.2 vs. 69.4%, P=0.152) and previous sternotomy (15.7 vs. 16.7%, P=0.861) between both cannulation groups; while EuroSCORE I (11.5±4.0 vs. 12.7±4.2, P=0.031) and ASA Score (3.5±0.81 vs. 3.8±0.57, P=0.011) were significantly higher in the femoral artery cannulation group. Bypass (249±102 vs. 240±81 min, P=0.474), X-clamp (166±85 vs. 157±67 min, P=0.418) and circulatory arrest time (51.6±28.7 vs. 48.3±21.7 min, P=0.365) were similar between the groups as were lowest temperature (18.1±2.0 vs. 18.1±2.2, P=0.775). Postoperative neurologic deficit and 30-day mortality were comparable between both cannulation groups (11.7 vs. 7.2%, P=0.449 and 20.2 vs. 16.9%, P=0.699, central vs. peripheral cannulation). Multivariate analysis revealed only EuroScore I above 13 as single preoperative predictor for mortality. Conclusions AADA can be operated with both femoral and central cannulation with similar results. Risk for early mortality was driven by the preoperative clinical and hemodynamic status before operation rather than the cannulation technique. PMID:27563543

  2. Cerebral salt wasting syndrome in children with acute central nervous system injury.

    PubMed

    Jiménez, Raquel; Casado-Flores, Juan; Nieto, Monserrat; García-Teresa, María Angeles

    2006-10-01

    The purpose of this investigation was to describe the causes, clinical pattern, and treatment of cerebral salt wasting syndrome in children with acute central nervous system injury. This retrospective study focused on patients120 mEq/L), and volume depletion. Fourteen patients were identified with cerebral salt wasting syndrome, 12 after a neurosurgical procedure (8 brain tumor, 4 hydrocephalus) and 2 after severe brain trauma. In 11 patients the cerebral salt wasting syndrome was diagnosed during the first 48 hours of admission. Prevalence of cerebral salt wasting syndrome in neurosurgical children was 11.3/1000 surgical procedures. The minimum sodium was 122+/-7 mEq/L, the maximum urine osmolarity 644+/-59 mOsm/kgH2O. The maximum sodium supply was 1 mEq/kg/h (range, 0.1-2.4). The mean duration of cerebral salt wasting syndrome was 6+/-5 days (range 1-9). In conclusion, cerebral salt wasting syndrome can complicate the postoperative course of children with brain injury; it is frequently present after surgery for brain tumors and hydrocephalus and in patients with severe head trauma. Close monitoring of salt and fluid balance is essential to prevent severe neurologic and hemodynamic complications.

  3. Central Nervous System Involvement in Adult Acute Lymphoblastic Leukemia: Diagnostic Tools, Prophylaxis, and Therapy

    PubMed Central

    Del Principe, Maria Ilaria; Maurillo, Luca; Buccisano, Francesco; Sconocchia, Giuseppe; Cefalo, Mariagiovanna; De Santis, Giovanna; Di Veroli, Ambra; Ditto, Concetta; Nasso, Daniela; Postorino, Massimiliano; Refrigeri, Marco; Attrotto, Cristina; Del Poeta, Giovanni; Lo-Coco, Francesco; Amadori, Sergio; Venditti, Adriano

    2014-01-01

    In adult patients with acute lymphoblastic leukemia (ALL), Central Nervous System (CNS) involvement is associated with a very poor prognosis. The diagnostic assessment of this condition relies on the use of neuroradiology, conventional cytology (CC) and flow cytometry (FCM). Among these approaches, which is the gold standard it is still a matter of debate. Neuroradiology and CC have a limited sensitivity with a higher rate of false negative results. FCM demonstrated a superior sensitivity over CC, particularly when low levels of CNS infiltrating cells are present. Although prospective studies of a large series of patients are still awaited, a positive finding by FCM appears to anticipate an adverse outcome even if CC shows no infiltration. Current strategies for adult ALL CNS-directed prophylaxis or therapy involve systemic and intrathecal chemotherapy and radiation therapy. An early and frequent intrathecal injection of cytostatic combined with systemic chemotherapy is the most effective strategy to reduce the frequency of CNS involvement. In patients with CNS overt ALL, at diagnosis or upon relapse, allogeneic hematopoietic stem cell transplantation might be considered. This review discusses risk factors, diagnostic techniques for identification of CNS infiltration and modalities of prophylaxis and therapy to manage it. PMID:25408861

  4. [An experience in nursing an acute lymphocytic leukemia patient with Peripherally Inserted Central Catheter].

    PubMed

    Lee, Hsuan; Lee, Hsiu-Hua; Chen, Ching-Huey

    2005-04-01

    The Peripherally Inserted Central Catheter (PICC) is still in its infancy in Taiwan. It has many advantages, including safety, simplicity, and few complications during the insertion process. It is suitable for patients who need long-term parenteral administration of medication or chemotherapy. However, the duration of PICC implantation is around six months, or even up to one year. As a result, it is very important to educate patients to take care of themselves throughout the implantation period in order to prevent complications. This report describes the experience of nursing a forty-four-year old male patient who suffered from acute lymphocytic leukemia and received a PICC implantation while undergoing chemotherapy treatment. As a PICC case manager, the author utilized self-efficacy theory and devoted herself to nursing care, interviews and phone calls to collect valuable information. During the process of PICC implantation, the author analyzed the characteristics of this case and assisted the patient and his primary care giver in choosing a suitable catheter and self-care techniques to achieve minimal complications during implantation. It is hoped that, by sharing in her experience, nursing staff may enhance their ability to assist patients with PICC and to help them to maintain their quality of life.

  5. Glucose intolerance induced by blockade of central FGF receptors is linked to an acute stress response

    PubMed Central

    Rojas, Jennifer M.; Matsen, Miles E.; Mundinger, Thomas O.; Morton, Gregory J.; Stefanovski, Darko; Bergman, Richard N.; Kaiyala, Karl J.; Taborsky, Gerald J.; Schwartz, Michael W.

    2015-01-01

    iv glucose (given during the FSIGT) contributed to the rapid resolution of the sympathoadrenal response induced by icv FGFRi, we performed an additional study comparing groups that received iv saline or iv glucose 30 min after icv FGFRi. Our finding that elevated plasma catecholamine levels returned rapidly to baseline irrespective of whether rats subsequently received an iv bolus of saline or glucose indicates that the rapid reversal of sympathoadrenal activation following icv FGFRi was unrelated to the subsequent glucose bolus. Conclusions The effect of acute inhibition of central FGFR signaling to impair glucose tolerance likely involves a stress response associated with pronounced, but transient, sympathoadrenal activation and an associated reduction of insulin secretion. Whether this effect is a true consequence of FGFR blockade or involves an off-target effect of the FGFR inhibitor requires additional study. PMID:26266088

  6. Pars Plana Vitrectomy Combined with Internal Limiting Membrane Peeling to Treat Persistent Macular Edema after Anti-Vascular Endothelial Growth Factor Treatment in Cases of Ischemic Central Retinal Vein Occlusion

    PubMed Central

    Shirakata, Yukari; Fujita, Tomoyoshi; Nakano, Yuki; Shiraga, Fumio; Tsujikawa, Akitaka

    2016-01-01

    Objective To evaluate the efficacy of pars plana vitrectomy (PPV) combined with internal limiting membrane (ILM) peeling in cases of ischemic central retinal vein occlusion (CRVO) where macular edema (ME) persisted after anti-vascular endothelial growth factor (anti-VEGF) treatment. Methods Fifteen eyes with ischemic CRVO-related ME were included in the study. Nine were treated with panretinal photocoagulation after initial examination. Anti-VEGF agents were injected intravitreally. Persistent ME was treated with PPV combined with ILM peeling. During surgery, laser photocoagulation was further applied to the non-perfused area. Results Mean retinal thickness gradually decreased after surgery (p = 0.024 at 6 months), although visual acuity did not improve significantly during the follow-up period (14.7 ± 11.6 months). Neovascular glaucoma subsequently developed in three cases and a trabeculectomy was performed in one case. Conclusion In eyes with ischemic CRVO, PPV combined with ILM peeling contributed to a reduction in persistent ME. However, there was no significant improvement in visual acuity. PMID:26889152

  7. The neuroprotective effect of hyperbaric oxygen treatment on laser-induced retinal damage in rats

    NASA Astrophysics Data System (ADS)

    Vishnevskia-Dai, Victoria; Belokopytov, Mark; Dubinsky, Galina; Nachum, Gal; Avni, Isaac; Belkin, Michael; Rosner, Mordechai

    2005-04-01

    Retinal damage induced by mechanical trauma, ischemia or laser photocoagulation increases considerably by secondary degeneration processes. The spread of damage may be ameliorated by neuroprotection that is aimed at reducing the extent of the secondary degeneration and promote healing processes. Hyperbaric oxygen (HBO) treatment consists of inspiration of oxygen at higher than one absolute atmospheric pressure. Improved neural function was observed in patients with acute brain trauma or ischemia treated with HBO. This study was designed to evaluate the neuroprotective effect of hyperbaric oxygen (HBO) on laser induced retinal damage in a rat model. Standard argon laser lesions were created in 25 pigmented rats divided into three groups: Ten rats were treated immediately after the irradiation with HBO three times during the first 24 hr followed by 12 consecutive daily treatments. Five rats received a shorter treatment regimen of 10 consecutive HBO treatments. The control group (10 rats) underwent the laser damage with no additional treatment. The retinal lesions were evaluated 20 days after the injury. All outcome measures were improved by the longer HBO treatment (P<0.01). The shorter HBO treatment was less effective, showing an increase only in nuclei density at the central area of lesion (P< 0.01). Hyperbaric oxygen seems to exert a neuroprotective effect on laser-induced retinal damage in a rat model. In the range of HBO exposures studied, longer exposure provides more neuroprotection. These results encourage further evaluation of the potential therapeutic use of hyperbaric oxygen in diseases and injuries of the retina.

  8. Factors Predicting the Effects of Hybrid Assistive Limb Robot Suit during the Acute Phase of Central Nervous System Injury

    PubMed Central

    CHIHARA, Hideo; TAKAGI, Yasushi; NISHINO, Kazunari; YOSHIDA, Kazumichi; ARAKAWA, Yoshiki; KIKUCHI, Takayuki; TAKENOBU, Yohei; MIYAMOTO, Susumu

    2016-01-01

    To improve the activities of daily living of patients with injury to the central nervous system, physical therapy starting from the acute phase of the injury is important. Recently, the efficacy of physical therapy using a hybrid assistive limb (HAL) robot suit was reported. However, individual differences exist in the effects of HAL. We investigated factors predicting the effects of HAL in 15 patients at our institution with central nervous system injury, primarily due to stroke, who underwent training using HAL during the acute phase. Patients were classified as either “with HAL suitability” or “without HAL suitability” based on scores from 10-m walking speed, gait, satisfaction, and pain. In both groups, Brunnstrom stage before HAL intervention, Fugl-Meyer assessment (FMA), stroke impairment assessment set (SIAS), and functional independence measure (FIM) were evaluated. Although motor function items did not differ significantly, FIM cognitive function items (P = 0.036), visuospatial perception items on SIAS (P = 0.0277), and pain items on SIAS (P = 0.0122) differed significantly between groups. These results indicated that training using HAL does not involve pain in patients with central nervous system injury during the acute phase, and exhibits positive effects in patients without pain and with high communication ability and visuospatial perception function. When conducting HAL intervention, incorporating functional assessment scores (FIM and SIAS), including peripheral items, may be useful to predict the suitability of HAL. PMID:26538291

  9. Factors Predicting the Effects of Hybrid Assistive Limb Robot Suit during the Acute Phase of Central Nervous System Injury.

    PubMed

    Chihara, Hideo; Takagi, Yasushi; Nishino, Kazunari; Yoshida, Kazumichi; Arakawa, Yoshiki; Kikuchi, Takayuki; Takenobu, Yohei; Miyamoto, Susumu

    2016-01-01

    To improve the activities of daily living of patients with injury to the central nervous system, physical therapy starting from the acute phase of the injury is important. Recently, the efficacy of physical therapy using a hybrid assistive limb (HAL) robot suit was reported. However, individual differences exist in the effects of HAL. We investigated factors predicting the effects of HAL in 15 patients at our institution with central nervous system injury, primarily due to stroke, who underwent training using HAL during the acute phase. Patients were classified as either "with HAL suitability" or "without HAL suitability" based on scores from 10-m walking speed, gait, satisfaction, and pain. In both groups, Brunnstrom stage before HAL intervention, Fugl-Meyer assessment (FMA), stroke impairment assessment set (SIAS), and functional independence measure (FIM) were evaluated. Although motor function items did not differ significantly, FIM cognitive function items (P = 0.036), visuospatial perception items on SIAS (P = 0.0277), and pain items on SIAS (P = 0.0122) differed significantly between groups. These results indicated that training using HAL does not involve pain in patients with central nervous system injury during the acute phase, and exhibits positive effects in patients without pain and with high communication ability and visuospatial perception function. When conducting HAL intervention, incorporating functional assessment scores (FIM and SIAS), including peripheral items, may be useful to predict the suitability of HAL.

  10. Central nervous system effects of meclizine and dimenhydrinate: evidence of acute tolerance to antihistamines.

    PubMed

    Manning, C; Scandale, L; Manning, E J; Gengo, F M

    1992-11-01

    Relative daytime drowsiness and performance impairment produced by meclizine and dimenhydrinate was assessed in 24 healthy male volunteers. Subjects received either dimenhydrinate, 100 mg, at 8:00 AM, 12:00 PM, and 4:00 PM; meclizine, 50 mg, at 8:00 AM, with placebo at 12:00 PM and 4:00 PM; or placebo at all three times in this randomized, double-blind, three-way crossover study. Impairment of mental performance was assessed by choice reaction time testing and digit symbol substitution scores. Drowsiness was self-assessed on the Stanford Sleepiness Scale and on a visual analog scale. Both antihistamines produced changes in digit symbol substitution, recognition time, and subjective assessments of sleepiness different from placebo. Expressed as change from baseline, the greatest reductions in digit symbol substitution scores after dimenhydrinate occurred 3 hours after the first dose (6.6 +/- 7) and were not different from the greatest measured change after meclizine (5.8 +/- 8), which occurred 9 hours after the dose was administered. Similar results were obtained with the other psychometric test scores. Self-rated sleepiness after dimenhydrinate was greatest 1 hour after the first dose, and was significantly greater than the largest degree of sleepiness after meclizine, which occurred at 7 hours after the dose. The effects of the first dose of dimenhydrinate on psychometric test scores were compared with the magnitude of the effects produced by subsequent doses. The magnitude of effect of the first dose of dimenhydrinate was significantly greater than the magnitude of effect produced by subsequent doses. The data suggest the possibility that acute tolerance to central nervous system impairment develops with multiple doses of dimenhydrinate. PMID:1474173

  11. Reversibility of retinal microvascular changes in severe falciparum malaria.

    PubMed

    Maude, Richard J; Kingston, Hugh W F; Joshi, Sonia; Mohanty, Sanjib; Mishra, Saroj K; White, Nicholas J; Dondorp, Arjen M

    2014-09-01

    Malarial retinopathy allows detailed study of central nervous system vascular pathology in living patients with severe malaria. An adult with cerebral malaria is described who had prominent retinal whitening with corresponding retinal microvascular obstruction, vessel dilatation, increased vascular tortuosity, and blood retinal barrier leakage with decreased visual acuity, all of which resolved on recovery. Additional study of these features and their potential role in elucidating the pathogenesis of cerebral malaria is warranted.

  12. Genetic pediatric retinal diseases

    PubMed Central

    Say, Emil Anthony T.

    2014-01-01

    Hereditary pediatric retinal diseases are a diverse group of disorders with pathologies affecting different cellular structures or retinal development. Many can mimic typical pediatric retinal disease such as retinopathy of prematurity, vitreous hemorrhage, retinal detachment and cystoid macular edema. Multisystem involvement is frequently seen in hereditary pediatric retinal disease. A thorough history coupled with a good physical examination can oftentimes lead the ophthalmologist or pediatrician to the correct genetic test and correct diagnosis. In some instances, evaluation of parents or siblings may be required to determine familial involvement when the history is inconclusive or insufficient and clinical suspicion is high.

  13. Genetic pediatric retinal diseases.

    PubMed

    Say, Emil Anthony T

    2014-12-01

    Hereditary pediatric retinal diseases are a diverse group of disorders with pathologies affecting different cellular structures or retinal development. Many can mimic typical pediatric retinal disease such as retinopathy of prematurity, vitreous hemorrhage, retinal detachment and cystoid macular edema. Multisystem involvement is frequently seen in hereditary pediatric retinal disease. A thorough history coupled with a good physical examination can oftentimes lead the ophthalmologist or pediatrician to the correct genetic test and correct diagnosis. In some instances, evaluation of parents or siblings may be required to determine familial involvement when the history is inconclusive or insufficient and clinical suspicion is high. PMID:27625880

  14. The K(+)-Cl(-) Cotransporter KCC2 and Chloride Homeostasis: Potential Therapeutic Target in Acute Central Nervous System Injury.

    PubMed

    Wu, Haijian; Che, Xiaoru; Tang, Junjia; Ma, Feiqiang; Pan, Kun; Zhao, Mingfei; Shao, Anwen; Wu, Qun; Zhang, Jianmin; Hong, Yuan

    2016-05-01

    The K(+)-Cl(-) cotransporter-2 (KCC2) is a well-known member of the electroneutral cation-chloride cotransporters with a restricted expression pattern to neurons. This transmembrane protein mediates the efflux of Cl(-) out of neurons and exerts a critical role in inhibitory γ-aminobutyric acidergic (GABAergic) and glycinergic neurotransmission. Moreover, KCC2 participates in the regulation of various physiological processes of neurons, including cell migration, dendritic outgrowth, spine morphology, and dendritic synaptogenesis. It is important to note that down-regulation of KCC2 is associated with the pathogenesis of multiple neurological diseases, which is of particular relevance to acute central nervous system (CNS) injury. In this review, we aim to survey the pathogenic significance of KCC2 down-regulation under the condition of acute CNS injuries. We propose that further elucidation of the molecular mechanisms regarding KCC2 down-regulation after acute CNS injuries is necessary because of potential promising avenues for prevention and treatment of acute CNS injury. PMID:25941074

  15. Ghrelin Supresses Sympathetic Hyperexcitation in Acute Heart Failure in Male Rats: Assessing Centrally and Peripherally Mediated Pathways.

    PubMed

    Shirai, Mikiyasu; Joe, Natalie; Tsuchimochi, Hirotsugu; Sonobe, Takashi; Schwenke, Daryl O

    2015-09-01

    The hormone ghrelin prevents a dangerous increase in cardiac sympathetic nerve activity (SNA) after acute myocardial infarction (MI), although the underlying mechanisms remain unknown. This study aimed to determine whether ghrelin's sympathoinhibitory properties stem either from directly within the central nervous system, or via modulation of specific cardiac vagal inhibitory afferents. Cardiac SNA was recorded in urethane-anesthetized rats for 3 hours after the ligation of the left anterior descending coronary artery (ie, MI). Rats received ghrelin either sc (150 μg/kg) or intracerebroventricularly (5 μg/kg) immediately after the MI. In another two groups, the cervical vagi were denervated prior to the MI, followed by sc injection of either ghrelin or placebo. Acute MI induced a 188% increase in cardiac SNA, which was significantly attenuated in ghrelin-treated rats for both sc or intracerebroventricularly administration (36% and 76% increase, respectively). Consequently, mortality (47%) and the incidence of arrhythmic episodes (12 per 2 h) were improved with both routes of ghrelin administration (<13% and less than five per 2 h, respectively). Bilateral vagotomy significantly attenuated the cardiac SNA response to acute MI (99% increase). Ghrelin further attenuated the sympathetic response to MI in vagotomized rats so that the SNA response was comparable between vagotomized and vagal-intact MI rats treated with ghrelin. These results suggest that ghrelin may act primarily via a central pathway within the brain to suppress SNA after MI, although peripheral vagal afferent pathways may also contribute in part. The exact region(s) within the central nervous system whereby ghrelin inhibits SNA remains to be fully elucidated.

  16. Inferior retinal light exposure is more effective than superior retinal exposure in suppressing melatonin in humans

    NASA Technical Reports Server (NTRS)

    Glickman, Gena; Hanifin, John P.; Rollag, Mark D.; Wang, Jenny; Cooper, Howard; Brainard, George C.

    2003-01-01

    Illumination of different areas of the human retina elicits differences in acute light-induced suppression of melatonin. The aim of this study was to compare changes in plasma melatonin levels when light exposures of equal illuminance and equal photon dose were administered to superior, inferior, and full retinal fields. Nine healthy subjects participated in the study. Plexiglass eye shields were modified to permit selective exposure of the superior and inferior halves of the retinas of each subject. The Humphrey Visual Field Analyzer was used both to confirm intact full visual fields and to quantify exposure of upper and lower visual fields. On study nights, eyes were dilated, and subjects were exposed to patternless white light for 90 min between 0200 and 0330 under five conditions: (1) full retinal exposure at 200 lux, (2) full retinal exposure at 100 lux, (3) inferior retinal exposure at 200 lux, (4) superior retinal exposure at 200 lux, and (5) a dark-exposed control. Plasma melatonin levels were determined by radioimmunoassay. ANOVA demonstrated a significant effect of exposure condition (F = 5.91, p < 0.005). Post hoc Fisher PLSD tests showed significant (p < 0.05) melatonin suppression of both full retinal exposures as well as the inferior retinal exposure; however, superior retinal exposure was significantly less effective in suppressing melatonin. Furthermore, suppression with superior retinal exposure was not significantly different from that of the dark control condition. The results indicate that the inferior retina contributes more to the light-induced suppression of melatonin than the superior retina at the photon dosages tested in this study. Findings suggest a greater sensitivity or denser distribution of photoreceptors in the inferior retina are involved in light detection for the retinohypothalamic tract of humans.

  17. Acute tianeptine treatment selectively modulates neuronal activation in the central nucleus of the amygdala and attenuates fear extinction.

    PubMed

    Godsil, B P; Bontempi, B; Mailliet, F; Delagrange, P; Spedding, M; Jay, T M

    2015-11-01

    Antidepressant drugs are commonly prescribed treatments for anxiety disorders, and there is growing interest in understanding how these drugs impact fear extinction because extinction learning is pivotal to successful exposure-based therapy (EBT). A key objective within this domain is understanding how antidepressants alter the activation of specific elements of the limbic-based network that governs such fear processing. Chronic treatment with the antidepressant tianeptine has been shown to reduce the acquisition of extinction learning in rats, yet the drug's acute influence on activation in prefrontal and amygdalar regions, and on extinction learning are not well understood. To assess its influence on cellular activation, rats were injected with tianeptine and Fos immunoreactivity was measured in these regions. Acute tianeptine treatment selectively altered Fos expression within subdivisions of the central nucleus of the amygdala (CEA) in a bidirectional manner that varied in relation to ongoing activation within the capsular subdivision and its prefrontal and intra-amygdalar inputs. This pattern of results suggests that the drug can conditionally modulate the activation of CEA subdivisions, which contain microcircuits strongly implicated in fear processing. The effect of acute tianeptine was also examined with respect to the acquisition, consolidation and expression of fear extinction in rats. Acute tianeptine attenuated extinction learning as well as the recall of extinction memory, which underscores that acute dosing with the drug could alter learning during EBT. Together these findings provide a new perspective for understanding the mechanism supporting tianeptine's clinical efficacy, as well as its potential influence on CEA-based learning mechanisms. PMID:25560759

  18. Acute tianeptine treatment selectively modulates neuronal activation in the central nucleus of the amygdala and attenuates fear extinction.

    PubMed

    Godsil, B P; Bontempi, B; Mailliet, F; Delagrange, P; Spedding, M; Jay, T M

    2015-11-01

    Antidepressant drugs are commonly prescribed treatments for anxiety disorders, and there is growing interest in understanding how these drugs impact fear extinction because extinction learning is pivotal to successful exposure-based therapy (EBT). A key objective within this domain is understanding how antidepressants alter the activation of specific elements of the limbic-based network that governs such fear processing. Chronic treatment with the antidepressant tianeptine has been shown to reduce the acquisition of extinction learning in rats, yet the drug's acute influence on activation in prefrontal and amygdalar regions, and on extinction learning are not well understood. To assess its influence on cellular activation, rats were injected with tianeptine and Fos immunoreactivity was measured in these regions. Acute tianeptine treatment selectively altered Fos expression within subdivisions of the central nucleus of the amygdala (CEA) in a bidirectional manner that varied in relation to ongoing activation within the capsular subdivision and its prefrontal and intra-amygdalar inputs. This pattern of results suggests that the drug can conditionally modulate the activation of CEA subdivisions, which contain microcircuits strongly implicated in fear processing. The effect of acute tianeptine was also examined with respect to the acquisition, consolidation and expression of fear extinction in rats. Acute tianeptine attenuated extinction learning as well as the recall of extinction memory, which underscores that acute dosing with the drug could alter learning during EBT. Together these findings provide a new perspective for understanding the mechanism supporting tianeptine's clinical efficacy, as well as its potential influence on CEA-based learning mechanisms.

  19. Retinal remodeling in human retinitis pigmentosa.

    PubMed

    Jones, B W; Pfeiffer, R L; Ferrell, W D; Watt, C B; Marmor, M; Marc, R E

    2016-09-01

    Retinitis Pigmentosa (RP) in the human is a progressive, currently irreversible neural degenerative disease usually caused by gene defects that disrupt the function or architecture of the photoreceptors. While RP can initially be a disease of photoreceptors, there is increasing evidence that the inner retina becomes progressively disorganized as the outer retina degenerates. These alterations have been extensively described in animal models, but remodeling in humans has not been as well characterized. This study, using computational molecular phenotyping (CMP) seeks to advance our understanding of the retinal remodeling process in humans. We describe cone mediated preservation of overall topology, retinal reprogramming in the earliest stages of the disease in retinal bipolar cells, and alterations in both small molecule and protein signatures of neurons and glia. Furthermore, while Müller glia appear to be some of the last cells left in the degenerate retina, they are also one of the first cell classes in the neural retina to respond to stress which may reveal mechanisms related to remodeling and cell death in other retinal cell classes. Also fundamentally important is the finding that retinal network topologies are altered. Our results suggest interventions that presume substantial preservation of the neural retina will likely fail in late stages of the disease. Even early intervention offers no guarantee that the interventions will be immune to progressive remodeling. Fundamental work in the biology and mechanisms of disease progression are needed to support vision rescue strategies. PMID:27020758

  20. Genetics Home Reference: retinitis pigmentosa

    MedlinePlus

    ... Me Understand Genetics Home Health Conditions retinitis pigmentosa retinitis pigmentosa Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Retinitis pigmentosa is a group of related eye disorders that ...

  1. Retinal hemorrhages in newborn.

    PubMed

    Govind, A; Kumari, S; Lath, N K

    1989-02-01

    Two hundred and fifty eight newborn babies were studied for the presence of retinal hemorrhages between 1-3 days of birth. The overall incidence of retinal hemorrhages was found to be 18.9%. It was observed that the incidence of retinal hemorrhages was higher in unassisted vaginal deliveries than in assisted births. Also, a two fold higher incidence was noted in term infants as compared to preterm babies. No association was seen with birth asphyxia.

  2. The role of the immune system in central nervous system plasticity after acute injury.

    PubMed

    Peruzzotti-Jametti, L; Donegá, M; Giusto, E; Mallucci, G; Marchetti, B; Pluchino, S

    2014-12-26

    Acute brain injuries cause rapid cell death that activates bidirectional crosstalk between the injured brain and the immune system. In the acute phase, the damaged CNS activates resident and circulating immune cells via the local and systemic release of soluble mediators. This early immune activation is necessary to confine the injured tissue and foster the clearance of cellular debris, thus bringing the inflammatory reaction to a close. In the chronic phase, a sustained immune activation has been described in many CNS disorders, and the degree of this prolonged response has variable effects on spontaneous brain regenerative processes. The challenge for treating acute CNS damage is to understand how to optimally engage and modify these immune responses, thus providing new strategies that will compensate for tissue lost to injury. Herein we have reviewed the available information regarding the role and function of the innate and adaptive immune responses in influencing CNS plasticity during the acute and chronic phases of after injury. We have examined how CNS damage evolves along the activation of main cellular and molecular pathways that are associated with intrinsic repair, neuronal functional plasticity and facilitation of tissue reorganization.

  3. The role of the immune system in central nervous system plasticity after acute injury.

    PubMed

    Peruzzotti-Jametti, L; Donegá, M; Giusto, E; Mallucci, G; Marchetti, B; Pluchino, S

    2014-12-26

    Acute brain injuries cause rapid cell death that activates bidirectional crosstalk between the injured brain and the immune system. In the acute phase, the damaged CNS activates resident and circulating immune cells via the local and systemic release of soluble mediators. This early immune activation is necessary to confine the injured tissue and foster the clearance of cellular debris, thus bringing the inflammatory reaction to a close. In the chronic phase, a sustained immune activation has been described in many CNS disorders, and the degree of this prolonged response has variable effects on spontaneous brain regenerative processes. The challenge for treating acute CNS damage is to understand how to optimally engage and modify these immune responses, thus providing new strategies that will compensate for tissue lost to injury. Herein we have reviewed the available information regarding the role and function of the innate and adaptive immune responses in influencing CNS plasticity during the acute and chronic phases of after injury. We have examined how CNS damage evolves along the activation of main cellular and molecular pathways that are associated with intrinsic repair, neuronal functional plasticity and facilitation of tissue reorganization. PMID:24785677

  4. An animal model to study toxicity of central nervous system therapy for childhood acute lymphoblastic leukemia: Effects on behavior

    SciTech Connect

    Mullenix, P.J.; Kernan, W.J.; Tassinari, M.S.; Schunior, A.; Waber, D.P.; Howes, A.; Tarbell, N.J. )

    1990-10-15

    Central nervous system prophylactic therapy used in the treatment of acute lymphoblastic leukemia can reduce intelligence quotient scores and impair memory and attention in children. Cranial irradiation, intrathecal methotrexate, and steroids are commonly utilized in acute lymphoblastic leukemia therapy. How they induce neurotoxicity is unknown. This study employs an animal model to explore the induction of neurotoxicity. Male and female Sprague-Dawley rats at 17 and 18 days of age were administered 18 mg/kg prednisolone, 2 mg/kg methotrexate, and 1000 cGy cranial irradiation. Another 18-day-old group was administered 1000 cGy cranial irradiation but no drugs. Matching controls received saline and/or a sham exposure to radiation. All animals at 6 weeks and 4 months of age were tested for alterations in spontaneous behavior. A computer pattern recognition system automatically recorded and classified individual behavioral acts displayed during exploration of a novel environment. Measures of behavioral initiations, total time, and time structure were used to compare treated and control animals. A permanent sex-specific change in the time structure of behavior was induced by the prednisolone, methotrexate, and radiation treatment but not by radiation alone. Unlike hyperactivity, the effect consisted of abnormal clustering and dispersion of acts in a pattern indicative of disrupted development of sexually dimorphic behavior. This study demonstrates the feasibility of an animal model delineating the agent/agents responsible for the neurotoxicity of central nervous system prophylactic therapy.

  5. Review of peripherally inserted central catheters in the Singapore acute-care hospital.

    PubMed

    Chlebicki, M P; Teo, E K

    2003-10-01

    Peripherally inserted central catheters are frequently used whenever reliable central venous access is required for a prolonged period of time. The objective of this study was to review utilisation profile, complication rates and outcomes of patients who were treated in our hospital with the therapy that required placement of the peripherally inserted central catheter. We reviewed the medical records of all patients who had peripherally inserted central catheter placed between the beginning of July and the end of October 2002. Five patients who remained hospitalised at the time of review (six weeks after the last day of study period) were excluded. Seventy-eight patients with 94 peripherally inserted central catheters were analysed in detail. Sixty-four peripherally inserted central catheters (68.1%) were placed for prolonged antibiotic therapy, 27 (28.7%) mainly to administer total parenteral nutrition and 3 (3.2%) were inserted for other reasons. Catheters were in place before removal for a mean 17.2 days. Forty-eight catheters (51.1%) were removed after completion of therapy on average 20.2 days after insertion. Complications were frequent but minor. Thirty-three catheters (35.1%) were removed due to catheter-related complications. The most common complication were phlebitis followed by accidental removal. In summary, peripherally inserted central catheters proved to be reasonably safe and a reliable way of providing therapy requiring prolonged intravenous access. Complications were frequent but relatively minor. Complication rates in our study were similar to those reported in other studies on this subject. Peripherally inserted central catheters remain a convenient and reasonable alternative to other centrally or peripherally inserted venous devices.

  6. Central vein perforation during tunneled dialysis catheter insertion: principles of acute management.

    PubMed

    Pua, Uei

    2014-10-01

    Central venous perforation during dialysis catheter insertion is a potentially fatal complication. Prompt recognition and judicious initial steps are important in optimizing the outcome. The purpose of this manuscript is to illustrate the imaging features and steps in initial management.

  7. Acute and constitutive increases in central serotonin levels reduce social play behaviour in peri-adolescent rats

    PubMed Central

    Schiepers, Olga J. G.; Schoffelmeer, Anton N. M.; Cuppen, Edwin; Vanderschuren, Louk J. M. J.

    2007-01-01

    Rationale Serotonin is an important modulator of social behaviour. Individual differences in serotonergic signalling are considered to be a marker of personality that is stable throughout lifetime. While a large body of evidence indicates that central serotonin levels are inversely related to aggression and sexual behaviour in adult rats, the relationship between serotonin and social behaviour during peri-adolescence has hardly been explored. Objective To study the effect of acute and constitutive increases in serotonin neurotransmission on social behaviour in peri-adolescent rats. Materials and methods Social behaviour in peri-adolesent rats (28–35 days old) was studied after genetic ablation of the serotonin transporter, causing constitutively increased extra-neuronal serotonin levels, and after acute treatment with the serotonin reuptake inhibitor fluoxetine or the serotonin releasing agent 3,4-methylenedioxymethamphetamine (MDMA). A distinction was made between social play behaviour that mainly occurs during peri-adolescence, and non-playful social interactions that are abundant during the entire lifespan of rats. Results In serotonin transporter knockout rats, social play behaviour was markedly reduced, while non-playful aspects of social interaction were unaffected. Acute treatment with fluoxetine or MDMA dose-dependently inhibited social play behaviour. MDMA also suppressed non-playful social interaction but at higher doses than those required to reduce social play. Fluoxetine did not affect non-playful social interaction. Conclusions These data show that both acute and constitutive increases in serotonergic neurotransmission reduce social play behaviour in peri-adolescent rats. Together with our previous findings of reduced aggressive and sexual behaviour in adult serotonin transporter knockout rats, these data support the notion that serotonin modulates social behaviour in a trait-like manner. PMID:17661017

  8. Access to medicines for acute illness in middle income countries in Central America

    PubMed Central

    Emmerick, Isabel Cristina Martins; Luiza, Vera Lucia; Camacho, Luiz Antonio Bastos; Ross-Degnan, Dennis

    2013-01-01

    OBJECTIVE To analyze the main predictors of access to medicines for persons who experienced acute health conditions. METHODS This was a cross-sectional analytic study, based on data from household surveys. We examined the predictors of: (1) seeking care for acute illness in the formal health care system and (2) obtaining all medicines sought for the acute condition. RESULTS The significant predictors of seeking health care for acute illnesses were urban geographic location, head of household with secondary school education or above, age under 15, severity of illness perceived by the respondent, and having health insurance. The most important predictor of obtaining full access to medicines was seeking care in the formal health care system. People who sought care in the formal system were three times more likely to receive all the medicines sought (OR 3.0, 95%CI 2.3;4.0). For those who sought care in the formal health system, the strongest predictors of full access to medicines were seeking care in the private sector, having secondary school education or above, and positive perceptions of quality of health care and medicines in public sector health facilities. For patients who did not seek care in the formal health system, full access to medicines was more likely in Honduras or Nicaragua than in Guatemala. Urban geographic location, higher economic status, and male gender were also significant predictors. CONCLUSIONS A substantial part of the population in these three countries sought and obtained medicines outside of the formal health care system, which may compromise quality of care and pose a risk to patients. Determinants of full access to medicines inside and outside the formal health care system differ, and thus may require different strategies to improve access to medicines.  PMID:24626545

  9. Intravital video microscopy measurements of retinal blood flow in mice.

    PubMed

    Harris, Norman R; Watts, Megan N; Leskova, Wendy

    2013-01-01

    Alterations in retinal blood flow can contribute to, or be a consequence of, ocular disease and visual dysfunction. Therefore, quantitation of altered perfusion can aid research into the mechanisms of retinal pathologies. Intravital video microscopy of fluorescent tracers can be used to measure vascular diameters and bloodstream velocities of the retinal vasculature, specifically the arterioles branching from the central retinal artery and of the venules leading into the central retinal vein. Blood flow rates can be calculated from the diameters and velocities, with the summation of arteriolar flow, and separately venular flow, providing values of total retinal blood flow. This paper and associated video describe the methods for applying this technique to mice, which includes 1) the preparation of the eye for intravital microscopy of the anesthetized animal, 2) the intravenous infusion of fluorescent microspheres to measure bloodstream velocity, 3) the intravenous infusion of a high molecular weight fluorescent dextran, to aid the microscopic visualization of the retinal microvasculature, 4) the use of a digital microscope camera to obtain videos of the perfused retina, and 5) the use of image processing software to analyze the video. The same techniques can be used for measuring retinal blood flow rates in rats. PMID:24429840

  10. A Novel Rhabdovirus Associated with Acute Hemorrhagic Fever in Central Africa

    PubMed Central

    Slikas, Elizabeth; Steffen, Imke; Muyembe, Jean-Jacques; Sittler, Taylor; Veeraraghavan, Narayanan; Ruby, J. Graham; Wang, Chunlin; Makuwa, Maria; Mulembakani, Prime; Tesh, Robert B.; Mazet, Jonna; Rimoin, Anne W.; Taylor, Travis; Schneider, Bradley S.; Simmons, Graham; Delwart, Eric; Wolfe, Nathan D.; Chiu, Charles Y.; Leroy, Eric M.

    2012-01-01

    Deep sequencing was used to discover a novel rhabdovirus (Bas-Congo virus, or BASV) associated with a 2009 outbreak of 3 human cases of acute hemorrhagic fever in Mangala village, Democratic Republic of Congo (DRC), Africa. The cases, presenting over a 3-week period, were characterized by abrupt disease onset, high fever, mucosal hemorrhage, and, in two patients, death within 3 days. BASV was detected in an acute serum sample from the lone survivor at a concentration of 1.09×106 RNA copies/mL, and 98.2% of the genome was subsequently de novo assembled from ∼140 million sequence reads. Phylogenetic analysis revealed that BASV is highly divergent and shares less than 34% amino acid identity with any other rhabdovirus. High convalescent neutralizing antibody titers of >1∶1000 were detected in the survivor and an asymptomatic nurse directly caring for him, both of whom were health care workers, suggesting the potential for human-to-human transmission of BASV. The natural animal reservoir host or arthropod vector and precise mode of transmission for the virus remain unclear. BASV is an emerging human pathogen associated with acute hemorrhagic fever in Africa. PMID:23028323

  11. A novel rhabdovirus associated with acute hemorrhagic fever in central Africa.

    PubMed

    Grard, Gilda; Fair, Joseph N; Lee, Deanna; Slikas, Elizabeth; Steffen, Imke; Muyembe, Jean-Jacques; Sittler, Taylor; Veeraraghavan, Narayanan; Ruby, J Graham; Wang, Chunlin; Makuwa, Maria; Mulembakani, Prime; Tesh, Robert B; Mazet, Jonna; Rimoin, Anne W; Taylor, Travis; Schneider, Bradley S; Simmons, Graham; Delwart, Eric; Wolfe, Nathan D; Chiu, Charles Y; Leroy, Eric M

    2012-09-01

    Deep sequencing was used to discover a novel rhabdovirus (Bas-Congo virus, or BASV) associated with a 2009 outbreak of 3 human cases of acute hemorrhagic fever in Mangala village, Democratic Republic of Congo (DRC), Africa. The cases, presenting over a 3-week period, were characterized by abrupt disease onset, high fever, mucosal hemorrhage, and, in two patients, death within 3 days. BASV was detected in an acute serum sample from the lone survivor at a concentration of 1.09 × 10(6) RNA copies/mL, and 98.2% of the genome was subsequently de novo assembled from ≈ 140 million sequence reads. Phylogenetic analysis revealed that BASV is highly divergent and shares less than 34% amino acid identity with any other rhabdovirus. High convalescent neutralizing antibody titers of >1:1000 were detected in the survivor and an asymptomatic nurse directly caring for him, both of whom were health care workers, suggesting the potential for human-to-human transmission of BASV. The natural animal reservoir host or arthropod vector and precise mode of transmission for the virus remain unclear. BASV is an emerging human pathogen associated with acute hemorrhagic fever in Africa.

  12. Complete clinical recovery of a central pontine and extrapontine myelinolysis delayed onset in a child with acute myeloblastic leukemia.

    PubMed

    Yilmaz, D; Karapinar, B; Balkan, C; Ay, Y; Kavakli, K

    2011-02-01

    Central pontine myelinolysis (CPM) is a demyelinating disease of the pons often associated with the demyelination of extrapontine areas of the central nervous system. It typically occurs 0.5-7 days after a rapid increment in serum Na level in hyponatremic patients and may lead to death. A 2.5-year-old child with a diagnosis of acute myeloblastic leukemia developed febril neutropenia, diarrhea, gastrointestinal hemorrhage followed by pulmonary aspergillosis. He could not tolerate enteral nutrition. He was given broad spectrum antibiotics and antifungal treatment. Laboratory tests showed electrolyte abnormalities including hyponatremia, hypokalemia and hypophosphatemia in a chronic course. Twenty three days after a rapid correction of hyponatremia (16 mEq/L/24 h) he revealed flask quadriparesis, disphagia, mutism, irregular respiratory pattern and loss of cough and gag reflex. Cranial magnetic resonance showed central pontine and extrapontine myelinolysis. He required mechanical ventilation and then he regained his neurologic functions. He completed chemotherapy protocol and underwent hematopoietic stem cell transplantation. After 2.5 years of the occurrence of CPM he is in completely normal physical and neurological status. CPM is a very severe but rare disorder in children with underlying disease. In the presence of multiple etiologic factors it may reveal a delayed onset and optimum outcome can be seen even in the severe clinical presentation with adequate intensive support.

  13. Modern retinal laser therapy.

    PubMed

    Kozak, Igor; Luttrull, Jeffrey K

    2015-01-01

    Medicinal lasers are a standard source of light to produce retinal tissue photocoagulation to treat retinovascular disease. The Diabetic Retinopathy Study and the Early Treatment Diabetic Retinopathy Study were large randomized clinical trials that have shown beneficial effect of retinal laser photocoagulation in diabetic retinopathy and have dictated the standard of care for decades. However, current treatment protocols undergo modifications. Types of lasers used in treatment of retinal diseases include argon, diode, dye and multicolor lasers, micropulse lasers and lasers for photodynamic therapy. Delivery systems include contact lens slit-lamp laser delivery, indirect ophthalmocope based laser photocoagulation and camera based navigated retinal photocoagulation with retinal eye-tracking. Selective targeted photocoagulation could be a future alternative to panretinal photocoagulation. PMID:25892934

  14. Central noradrenergic mechanisms and the acute stress response during painful stimulation.

    PubMed

    Chapman, C Richard; Bradshaw, David H; Donaldson, Gary W; Jacobson, Robert C; Nakamura, Yoshio

    2014-12-01

    Events that threaten tissue integrity including noxious stimulation activate central noradrenergic circuits, particularly locus coeruleus and its projections. Recent advances in theory hold that an adaptive, defensive shift in brain activity takes place in response to threat. In principle, this shift may accentuate the autonomic and central biomarkers of the perception of painful events and the experience of pain itself. We have examined the effects of an alpha-2 agonist on pupil dilation responses, skin conductance responses, near field somatosensory evoked potentials and pain reports in normal volunteers undergoing repeated trials of painful fingertip stimulation delivered at low, medium and high intensities. In a double-blinded study, 114 healthy male and female volunteers underwent repeated noxious stimulation under baseline, placebo and active drug conditions where the active drug was the alpha-2 agonist tizanidine 4 mg. In contrast to baseline and placebo conditions, tizanidine 4 mg significantly reduced the magnitudes of the mean pupil dilation response, the mean skin conductance response, the mean near field somatosensory evoked potential peak-to-peak amplitude and the mean pain intensity rating. Stimulus intensity significantly altered all three biomarkers and the pain report in a graded fashion. There were no sex differences. These findings support the hypotheses that painful events activate central noradrenergic circuits, and that these circuits play a role in the autonomic and central arousal associated with pain. PMID:25122041

  15. Central nervous system toxicity after acute oral formaldehyde exposure in rabbits: An experimental study.

    PubMed

    Arici, S; Karaman, S; Dogru, S; Cayli, S; Arici, A; Suren, M; Karaman, T; Kaya, Z

    2014-11-01

    Formaldehyde (FA) is one of the most widely used chemical compounds in industrial field. It is described as toxic, particularly to the nervous system, the urogenital system, and the respiratory tracts. In this study, we determined the effects of acute oral exposure to FA in rabbit brain tissue. A total of 16 rabbits were selected and divided into 2 groups: formaldehyde group (group F) and control group (group C). FA was administered to group F at a rate of 40 mg/kg/day via a nasogastric tube for 5 days. Saline was similarly administered to the eight controls. All the animals were euthanized after 5 days of exposure, and brain tissue samples were collected in 10% neutral formalin and embedded in paraffin. To investigate the effects of FA on the apoptotic process, we examined active caspase-3, Bax, and Bcl-2 immunohistochemical expression and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate -biotin nick-end labeling (TUNEL) reactivity in the rabbit brains. In addition, glial fibrillary acidic protein (GFAP) was biochemically assessed in brain tissue samples for neurotoxicity. We found that FA treatment caused a significant decrease in Bcl-2 expression and an increase in active caspase-3 and Bax expressions as well as an increase in the number of TUNEL-positive apoptotic cells. The GFAP level was found to be significantly higher in group F. In conclusion, acute oral exposure to FA caused DNA damage, apoptosis, and neuronal injury in the rabbit brains.

  16. Integrated computer-aided retinal photocoagulation system

    NASA Astrophysics Data System (ADS)

    Barrett, Steven F.; Wright, Cameron H. G.; Oberg, Erik D.; Rockwell, Benjamin A.; Cain, Clarence P.; Jerath, Maya R.; Rylander, Henry G., III; Welch, Ashley J.

    1996-05-01

    Successful retinal tracking subsystem testing results in vivo on rhesus monkeys using an argon continuous wave laser and an ultra-short pulse laser are presented. Progress on developing an integrated robotic retinal laser surgery system is also presented. Several interesting areas of study have developed: (1) 'doughnut' shaped lesions that occur under certain combinations of laser power, spot size, and irradiation time complicating measurements of central lesion reflectance, (2) the optimal retinal field of view to achieve simultaneous tracking and lesion parameter control, and (3) a fully digital versus a hybrid analog/digital tracker using confocal reflectometry integrated system implementation. These areas are investigated in detail in this paper. The hybrid system warrants a separate presentation and appears in another paper at this conference.

  17. The analgesic effect of electroacupuncture on acute thermal pain perception-a central neural correlate study with fMRI

    PubMed Central

    2011-01-01

    Background Electrical acupuncture (EA) has been utilized in acute pain management. However, the neuronal mechanisms that lead to the analgesic effect are still not well defined. The current study assessed the intensity [optimal EA (OI-EA) vs. minimal EA (MI-EA)] effect of non-noxious EA on supraspinal regions related to noxious heat pain (HP) stimulation utilizing an EA treatment protocol for acute pain and functional magnetic resonance imaging (fMRI) with correlation in behavioral changes. Subjects underwent five fMRI scanning paradigms: one with heat pain (HP), two with OI-EA and MI-EA, and two with OI-EA and HP, and MI-EA and HP. Results While HP resulted in activations (excitatory effect) in supraspinal areas known for pain processing and perception, EA paradigms primarily resulted in deactivations (suppressive effect) in most of these corresponding areas. In addition, OI-EA resulted in a more robust supraspinal sedative effect in comparison to MI-EA. As a result, OI-EA is more effective than MI-EA in suppressing the excitatory effect of HP in supraspinal areas related to both pain processing and perception. Conclusion Intensities of EA plays an important role in modulating central pain perception. PMID:21645415

  18. Acute, painless vision loss.

    PubMed

    Beran, David I; Murphy-Lavoie, Heather

    2009-01-01

    This article provides a review of various conditions causing sudden, painless vision loss. The conditions of amaurosis fugax, central retinal artery occlusion (CRAO), central retinal vein occlusion (CRVO), vitreous hemorrhage, ischemic optic neuropathies (ION), posterior cerebrovascular accidents, and retinal detachment (RD) are discussed. The history, physical, pathophysiology, and treatment of each disease state are discussed along with possible preventative measures for each. An emphasis is made on early ophthalmologic involvement for potential vision restoration and the importance of a thorough history and physical for all patients with ocular complaints. PMID:19785313

  19. Neonatal overfeeding attenuates acute central pro-inflammatory effects of short-term high fat diet

    PubMed Central

    Cai, Guohui; Dinan, Tara; Barwood, Joanne M.; De Luca, Simone N.; Soch, Alita; Ziko, Ilvana; Chan, Stanley M. H.; Zeng, Xiao-Yi; Li, Songpei; Molero, Juan; Spencer, Sarah J.

    2015-01-01

    Neonatal obesity predisposes individuals to obesity throughout life. In rats, neonatal overfeeding also leads to early accelerated weight gain that persists into adulthood. The phenotype is associated with dysfunction in a number of systems including paraventricular nucleus of the hypothalamus (PVN) responses to psychological and immune stressors. However, in many cases weight gain in neonatally overfed rats stabilizes in early adulthood so the animal does not become more obese as it ages. Here we examined if neonatal overfeeding by suckling rats in small litters predisposes them to exacerbated metabolic and central inflammatory disturbances if they are also given a high fat diet in later life. In adulthood we gave the rats normal chow, 3 days, or 3 weeks high fat diet (45% kcal from fat) and measured peripheral indices of metabolic disturbance. We also investigated hypothalamic microglial changes, as an index of central inflammation, as well as PVN responses to lipopolysaccharide (LPS). Surprisingly, neonatal overfeeding did not predispose rats to the metabolic effects of a high fat diet. Weight changes and glucose metabolism were unaffected by the early life experience. However, short term (3 day) high fat diet was associated with more microglia in the hypothalamus and a markedly exacerbated PVN response to LPS in control rats; effects not seen in the neonatally overfed. Our findings indicate neonatally overfed animals are not more susceptible to the adverse metabolic effects of a short-term high fat diet but may be less able to respond to the central effects. PMID:25628527

  20. KR-31378, a potassium-channel opener, induces the protection of retinal ganglion cells in rat retinal ischemic models.

    PubMed

    Choi, Anho; Choi, Jun-Sub; Yoon, Yone-Jung; Kim, Kyung-A; Joo, Choun-Ki

    2009-04-01

    KR-31378 is a newly developed K(ATP)-channel opener. To investigate the ability of KR-31378 to protect retinal ganglion cells (RGC), experiments were conducted using two retinal ischemia models. Retinal ischemia was induced by transient high intraocular pressure (IOP) for acute ischemia and by three episcleral vein occlusion for chronic retinal ischemia. KR-31378 was injected intraperitoneally and administered orally in the acute and chronic ischemia models, respectively. Under the condition of chronic ischemia, RGC density in the KR-31378-treated group was statistically higher than that in the non-treated group, and IOP was reduced. In the acute retinal ischemia model, 90% of RGC were degenerated after one week in non-treated retina, but, RGC in KR-31378-treated retina were protected from ischemic damage in a dose-dependent manner and showed inhibited glial fibrillary acidic protein (GFAP) expression. Furthermore, the KR-31378 protective effect was inhibited by glibenclamide treatment in acute ischemia. These findings indicate that systemic KR-31378 treatment may protect against ischemic injury-induced ganglion cell loss in glaucoma.

  1. Acute low-level microwave exposure and central cholinergic activity: studies on irradiation parameters

    SciTech Connect

    Lai, H.; Horita, A.; Guy, A.W.

    1988-01-01

    Sodium-dependent high-affinity choline uptake was measured in the striatum, frontal cortex, hippocampus, and hypothalamus of rats after acute exposure (45 min) to pulsed (2 microseconds, 500 pps) or continuous-wave 2,450-MHz microwaves in cylindrical waveguides or miniature anechoic chambers. In all exposure conditions, the average whole-body specific absorption rate was at 0.6 W/kg. Decrease in choline uptake was observed in the frontal cortex after microwave exposure in all of the above irradiation conditions. Regardless of the exposure system used, hippocampal choline uptake was decreased after exposure to pulsed but not continuous-wave microwaves. Striatal choline uptake was decreased after exposure to either pulsed or continuous-wave microwaves in the miniature anechoic chamber. No significant change in hypothalamic choline uptake was observed under any of the exposure conditions studied. We conclude that depending on the parameters of the radiation, microwaves can elicit specific and generalized biological effects.

  2. Classification of left and right eye retinal images

    NASA Astrophysics Data System (ADS)

    Tan, Ngan Meng; Liu, Jiang; Wong, Damon W. K.; Zhang, Zhuo; Lu, Shijian; Lim, Joo Hwee; Li, Huiqi; Wong, Tien Yin

    2010-03-01

    Retinal image analysis is used by clinicians to diagnose and identify, if any, pathologies present in a patient's eye. The developments and applications of computer-aided diagnosis (CAD) systems in medical imaging have been rapidly increasing over the years. In this paper, we propose a system to classify left and right eye retinal images automatically. This paper describes our two-pronged approach to classify left and right retinal images by using the position of the central retinal vessel within the optic disc, and by the location of the macula with respect to the optic nerve head. We present a framework to automatically identify the locations of the key anatomical structures of the eye- macula, optic disc, central retinal vessels within the optic disc and the ISNT regions. A SVM model for left and right eye retinal image classification is trained based on the features from the detection and segmentation. An advantage of this is that other image processing algorithms can be focused on regions where diseases or pathologies and more likely to occur, thereby increasing the efficiency and accuracy of the retinal CAD system/pathology detection. We have tested our system on 102 retinal images, consisting of 51 left and right images each and achieved and accuracy of 94.1176%. The high experimental accuracy and robustness of this system demonstrates that there is potential for this system to be integrated and applied with other retinal CAD system, such as ARGALI, for a priori information in automatic mass screening and diagnosis of retinal diseases.

  3. Retinal and optic nerve diseases.

    PubMed

    Margalit, Eyal; Sadda, Srinivas R

    2003-11-01

    A variety of disease processes can affect the retina and/or the optic nerve, including vascular or ischemic disease, inflammatory or infectious disease, and degenerative disease. These disease processes may selectively damage certain parts of the retina or optic nerve, and the specific areas that are damaged may have implications for the design of potential therapeutic visual prosthetic devices. Outer retinal diseases include age-related macular degeneration, pathologic myopia, and retinitis pigmentosa. Although the retinal photoreceptors may be lost, the inner retina is relatively well-preserved in these diseases and may be a target for retinal prosthetic devices. Inner retinal diseases include retinal vascular diseases such as diabetic retinopathy, retinal venous occlusive disease, and retinopathy of prematurity. Other retinal diseases such as ocular infections (retinitis, endophthalmitis) may affect all retinal layers. Because the inner retinal cells, including the retinal ganglion cells, may be destroyed in these diseases (inner retinal or whole retinal), prosthetic devices that stimulate the inner retina may not be effective. Common optic nerve diseases include glaucoma, optic neuritis, and ischemic optic neuropathy. Because the ganglion cell nerve fibers themselves are damaged, visual prosthetics for these diseases will need to target more distal portions of the visual pathway, such as the visual cortex. Clearly, a sound understanding of retinal and optic nerve disease pathophysiology is critical for designing and choosing the optimal visual prosthetic device.

  4. Central nervous system involvement at first relapse in patients with acute promyelocytic leukemia treated with all-trans retinoic acid and anthracycline monochemotherapy without intrathecal prophylaxis

    PubMed Central

    Montesinos, Pau; Díaz-Mediavilla, Joaquín; Debén, Guillermo; Prates, Virginia; Tormo, Mar; Rubio, Vicente; Pérez, Inmaculada; Fernández, Isolda; Viguria, Maricruz; Rayón, Chelo; González, José; de la Serna, Javier; Esteve, Jordi; Bergua, Juan M.; Rivas, Concha; González, Marcos; González, Jose D.; Negri, Silvia; Brunet, Salut; Lowenberg, Bob; Sanz, Miguel A.

    2009-01-01

    Background The prevalence of and risk factors for central nervous system recurrence in patients with acute promyelocytic leukemia are not well established and remain a controversial matter. Design and Methods Between 1996 and 2005, 739 patients with newly diagnosed acute promyelocytic leukemia enrolled in two consecutive trials (PETHEMA LPA96 and LPA99) received induction therapy with all-trans retinoic acid and idarubicin. Consolidation therapy comprised three courses of anthracycline monochemotherapy (LPA96), with all-trans retinoic acid and reinforced doses of idarubicin in patients with an intermediate or high risk of relapse (LPA99). Central nervous system prophylaxis was not given. Results Central nervous system relapse was documented in 11 patients. The 5-year cumulative incidence of central nervous system relapse was 1.7% (LPA96 3.2% and LPA99 1.2%; p=0.09). The cumulative incidence was 0%, 0.8%, and 5.5% in low-, intermediate-, and high-risk patients, respectively. Relapse risk score (p=0.0001) and the occurrence of central nervous system hemorrhage during induction (5-year cumulative incidence 18.7%, p=0.006) were independent risk factors for central nervous system relapse. Conclusions This study shows a low incidence of central nervous system relapse in patients with acute promyelocytic leukemia following therapy with all-trans retinoic acid and anthracycline without specific central nervous system prophylaxis. Central nervous system relapse was significantly associated with high white blood cell counts and prior central nervous system hemorrhage, which emerged as independent prognostic factors. PMID:19608685

  5. Relationship between retinal vascular occlusions and incident cerebrovascular diseases

    PubMed Central

    Zhou, Yue; Zhu, Wengen; Wang, Changyun

    2016-01-01

    Abstract Several studies investigating the role of retinal vascular occlusions, on cerebrovascular diseases (CVD) have been reported, but the results are still inconsistent. We therefore sought to evaluate the relationship between retinal vascular occlusions and CVD. We systematically searched the Cochrane Library, PubMed, and ScienceDirect databases through January 31, 2016 for studies evaluating the effect of retinal vascular occlusions on the risk of CVD. Data were abstracted using predefined criteria, and then pooled by RevMan 5.3 software. A total of 9 retrospective studies were included in this meta-analysis. When compared with individuals without retinal vascular occlusions, both individuals with retinal artery occlusion (RAO) (odds ratio [OR] = 2.01, 95% confidence interval [CI]: 1.21–3.34; P = 0.005) and individuals with retinal vein occlusion (RVO) (OR = 1.37, 95% CI: 1.24–1.50; P < 0.00001) had higher risks of developing CVD. Additionally, both individuals with central retinal artery occlusion (CRAO) (OR = 2.00, 95% CI: 1.12–3.56; P = 0.02) and branch retinal artery occlusion (BRAO) (OR = 1.60, 95% CI: 1.03–1.48; P = 0.04) were significantly associated with increased risk of CVD. Published literatures support both RVO and RAO are associated with increased risks of CVD. Further prospective studies are needed to confirm these findings. PMID:27368050

  6. Retinal oximeter for the blue-green oximetry technique

    NASA Astrophysics Data System (ADS)

    Denninghoff, Kurt R.; Sieluzycka, Katarzyna B.; Hendryx, Jennifer K.; Ririe, Tyson J.; Deluca, Lawrence; Chipman, Russell A.

    2011-10-01

    Retinal oximetry offers potential for noninvasive assessment of central venous oxyhemoglobin saturation (SO2) via the retinal vessels but requires a calibrated accuracy of +/-3% saturation in order to be clinically useful. Prior oximeter designs have been hampered by poor saturation calibration accuracy. We demonstrate that the blue-green oximetry (BGO) technique can provide accuracy within +/-3% in swine when multiply scattered light from blood within a retinal vessel is isolated. A noninvasive on-axis scanning retinal oximeter (ROx-3) is constructed that generates a multiwavelength image in the range required for BGO. A field stop in the detection pathway is used in conjunction with an anticonfocal bisecting wire to remove specular vessel reflections and isolate multiply backscattered light from the blood column within a retinal vessel. This design is tested on an enucleated swine eye vessel and a retinal vein in a human volunteer with retinal SO2 measurements of ~1 and ~65%, respectively. These saturations, calculated using the calibration line from earlier work, are internally consistent with a standard error of the mean of +/-2% SO2. The absolute measures are well within the expected saturation range for the site (-1 and 63%). This is the first demonstration of noninvasive on-axis BGO retinal oximetry.

  7. Inner retinal change in a novel rd1-FTL mouse model of retinal degeneration.

    PubMed

    Greferath, Ursula; Anderson, Emily E; Jobling, Andrew I; Vessey, Kirstan A; Martinez, Gemma; de Iongh, Robb U; Kalloniatis, Michael; Fletcher, Erica L

    2015-01-01

    While photoreceptor loss is the most devastating result of inherited retinal degenerations such as retinitis pigmentosa, inner retinal neurons also undergo significant alteration. Detailing these changes has become important as many vision restorative therapies target the remaining neurons. In this study, the rd1-Fos-Tau-LacZ (rd1-FTL) mouse model was used to explore inner retinal change at a late stage of retinal degeneration, after the loss of photoreceptor nuclei. The rd1-FTL model carries a mutation in the phosphodiesterase gene, Pde6b, and an axonally targeted transgenic beta galactosidase reporter system under the control of the c-fos promoter. Retinae of transgenic rd1-FTL mice and control FTL animals aged 2-12 months were processed for indirect fluorescence immunocytochemistry. At 2 months of age, a time when the majority of photoreceptor nuclei are lost, there was negligible c-fos reporter (FTL) expression, however, from 4 months, reporter expression was observed to increase within subpopulations of amacrine and ganglion cells within the central retina. These areas of inner retinal FTL expression coincided with regions that contained aberrant Müller cells. Specifically, these cells exhibited reduced glutamine synthetase and Kir4.1 immunolabelling, whilst showing evidence of proliferative gliosis (increased cyclinD1 and glial fibrillary acidic protein expression). These changes were limited to distinct regions where cone photoreceptor terminals were absent. Overall, these results highlight that distinct areas of the rd1-FTL central retina undergo significant glial alterations after cone photoreceptor loss. These areas coincide with up-regulation of the c-fos reporter in the inner retina, which may represent a change in neuronal function/plasticity. The rd1-FTL mouse is a useful model system to probe changes that occur in the inner retina at later stages of retinal degeneration. PMID:26283925

  8. Acute central stimulation of luteinizing hormone by parenterally administered N-methyl-D,L-aspartic acid in the male rat.

    PubMed

    Schainker, B A; Cicero, T J

    1980-02-24

    N-methyl-D,L-aspartic acid (NMA), a potent neuroexcitatory and neurotoxic glutamic acid analogue, acutely elevated serum luteinizing hormone (LH) in male rats when given subcutaneously in doses below those that cause morphologically detectable hypothalamic neurotoxicity. NMA treatment in doses known to be subtoxic by morphological criteria fails to induce any permanent neuroendocrine dysfunction as assessed by several physiological parameters, including NMA responsiveness after multiple consecutive dosees spaced at 24 h intervals, subsequent basal LH levels and subsequent postcastration LH elevations. Like naloxone, NMA elevates serum LH by reversibly stimulating a central labile pool. Neither has a direct stimulatory effect on the pituitary in vitro. Treatment with either attenuates naloxone-induced LH stimulation 2 h, but not 14 days, later while pituitary responsiveness to LHRH in vivo remains unaltered. Neither NMA nor naloxone is dependent upon testosterone for its LH stimulatory action and both increase serum LH through physiological mechanisms responsive to testosterone inhibition. It is concluded that subtoxic LH stimulating doses of NMA provide a useful tool in discerning neurotransmitter systems involved in central control of the hypothalamic-pituitary-gonadal axis.

  9. Central hemodynamic responses during acute high-intensity interval exercise and moderate continuous exercise in patients with heart failure.

    PubMed

    Gayda, Mathieu; Normandin, Eve; Meyer, Philippe; Juneau, Martin; Haykowsky, Mark; Nigam, Anil

    2012-12-01

    The aim of this study was to compare the acute hemodynamic responses during high-intensity intermittent exercise (HIIE) session compared with moderate-intensity continuous exercise (MICE) session in patients with heart failure and reduced ejection fraction (HFREF). Thirteen patients with HFREF (age, 59 ± 6 years; left ventricular ejection fraction, 27% ± 6%; New York Heart Association class I to III) were randomly assigned to a single session of HIIE (2 × 8 min) corresponding to 30 s at 100% of peak power output (PPO) and 30 s passive recovery intervals or to a MICE (22 min) at 60% of PPO. Gas exchange and central hemodynamic parameters (cardiac bioimpedance) were measured continuously during exercise. Oxygen uptake, stroke volume (SV), cardiac output (CO), and arterio-venous difference (C(a-v)O(2)) were compared. Mean oxygen uptake and ventilation were lower during HIIE vs. MICE. CO, SV, and C(a-v)O(2)) were not different between MICE and HIIE. Optimized HIIE was well tolerated (similar perceived exertion) and no significant ventricular arrhythmias and (or) abnormal blood pressure responses occurred during HIEE session. Compared with MICE, optimized HIIE elicited similar central hemodynamic and C(a-v)O(2) responses in HFREF patients with lower oxygen uptake and ventilation. HIIE may be an efficient exercise training modality in patients with HFREF.

  10. Retinal vein occlusion

    MedlinePlus

    ... most often caused by hardening of the arteries ( atherosclerosis ) and the formation of a blood clot. Blockage ... arteries that have been thickened or hardened by atherosclerosis cross over and place pressure on a retinal ...

  11. Retinal artery occlusion

    MedlinePlus

    ... eds. Textbook of Family Medicine . 9th ed. Philadelphia, PA: Elsevier; 2016:chap 17. Duker JS. Retinal arterial ... M, Duker JS, eds. Ophthalmology. 4th ed. Philadelphia, PA: Elsevier; 2014:chap 6.18. Reiss GR, Sipperley ...

  12. [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.

  13. Retinal Proliferation Response in the Buphthalmic Zebrafish, bugeye

    PubMed Central

    Sherpa, Tshering; Hunter, Samuel S.; Frey, Ruth A.; Robison, Barrie D.; Stenkamp, Deborah L.

    2011-01-01

    The zebrafish retina regenerates in response to acute retinal lesions, replacing damaged neurons with new neurons. In this study we test the hypothesis that chronic stress to inner retinal neurons also triggers a retinal regeneration response in the bugeye zebrafish. Mutations in the lrp2 gene in zebrafish are associated with a progressive eye phenotype (bugeye) that models several risk factors for human glaucoma including buphthalmos (enlarged eyes), elevated intraocular pressure (IOP), and upregulation of genes related to retinal ganglion cell pathology. The retinas of adult bugeye zebrafish showed high rates of ongoing proliferation which resulted in the production of a small number of new retinal neurons, particularly photoreceptors. A marker of mechanical cell stress, Hsp27, was strongly expressed in inner retinal neurons and glia of bugeye retinas. The more enlarged eyes of individual bugeye zebrafish showed disrupted retinal lamination, and a persistent reduced density of neurons in the ganglion cell layer (GCL), although total numbers of GCL neurons were higher than in control eyes. Despite the presence of a proliferative response to damage, the adult bugeye zebrafish remained behaviorally blind. These findings suggest the existence of an unsuccessful regenerative response to a persistent pathological condition in the bugeye zebrafish. PMID:21723280

  14. Retinal detachment in pseudophakia.

    PubMed

    Galin, M A; Poole, T A; Obstbaum, S A

    1979-07-01

    In a series of cataract patients excluding myopic individuals, under age 60 years, and cases in which vitreous loss occurred, retinal detachment was no less frequent after intracapsular cataract extraction and Sputnik iris supported lenses than in controls. Both groups were followed up for a minimum of two years. The detachments predominantly occurred from retinal breaks in areas of the retina that looked normal preoperatively. PMID:464014

  15. Contrasting effects of acute vs. chronic tricyclic antidepressant treatment on central morphine analgesia.

    PubMed

    Kellstein, D E; Malseed, R T; Goldstein, F J

    1984-12-01

    Antinociception following central opioid microinjection in rats was assessed weekly via a tail-flick procedure during chronic tricyclic antidepressant (TCA) treatment. (1) Daily TCA: Subcutaneous injections of desipramine (DMI), 30 mg/kg, chlorimipramine (CMI), 10 mg/kg, or saline, 1 ml/kg, were given daily for 22 days. Morphine sulfate (M), 5 micrograms, was microinjected into the ventrolateral periaqueductal gray (VLPAG) at 7 day intervals. On day 1, DMI or CMI enhanced M analgesia whereas saline did not. Augmentation of M disappeared by days 8 and 15 for CMI and DMI, respectively, and was replaced by attenuation which was still observed on day 22 for both TCAs. L-Tryptophan (LT), 100 mg/kg, i.p., on days 15 and 22 temporarily restored TCA enhancement of M. Fourteen days after cessation of all daily TCA treatments, enhancement of M by CMI was similar to that observed on day 1, whereas recovery of DMI-induced facilitation was incomplete. (2) Weekly TCA: Weekly treatment with DMI, CMI, or saline in the same doses as above had similar effects. M analgesia was enhanced by the TCAs but not saline on day 1; this facilitation was absent by day 15. Attenuation of M by DMI or CMI was evident on day 22; 2 weeks after cessation of all weekly TCA treatments, complete recovery of TCA-induced augmentation was observed. Loss of M facilitation during chronic daily or weekly TCA administration may be related to reduction of central opioid and/or 5-HT2 receptors. PMID:6097858

  16. Blockade of central vasopressin receptors reduces the cardiovascular response to acute stress in freely moving rats.

    PubMed

    Stojicić, S; Milutinović-Smiljanić, S; Sarenac, O; Milosavljević, S; Paton, J F R; Murphy, D; Japundzić-Zigon, N

    2008-04-01

    To investigate the contribution of central vasopressin receptors to blood pressure (BP) and heart rate (HR) response to stress we injected non-peptide selective V(1a) (SR49059), V(1b) (SSR149415), V(2) (SR121463) receptor antagonists, diazepam or vehicle in the lateral cerebral ventricle of conscious freely moving rats stressed by blowing air on their heads for 2 min. Cardiovascular effects of stress were evaluated by analyzing maximum increase of BP and HR (MAX), latency of maximum response (LAT), integral under BP and HR curve (integral), duration of their recovery and spectral parameters of BP and HR indicative of increased sympathetic outflow (LF(BP) and LF/HF(HR)). Moreover, the increase of serum corticosterone was measured. Exposure to air-jet stress induced simultaneous increase in BP and HR followed by gradual decline during recovery while LF(BP) oscillation remained increased as well as serum corticosterone level. Rats pre-treated with vasopressin receptor antagonists were not sedated while diazepam induced sedation that persisted during exposure to stress. V(1a), V(1b) and V(2) receptor antagonists applied separately did not modify basal values of cardiovascular parameters but prevented the increase in integral(BP). In addition, V(1b) and V(2) receptor antagonists reduced BP(MAX) whereas V(1a), V(1b) antagonist and diazepam reduced HR(MAX) induced by exposure to air-jet stress. All drugs shortened the recovery period, prevented the increase of LF(BP) without affecting the increase in serum corticosterone levels. Results indicate that vasopressin receptors located within the central nervous system mediate, in part, the cardiovascular response to air-jet stress without affecting either the neuroendocrine component or inducing sedation. They support the view that the V(1b) receptor antagonist may be of potential therapeutic value in reducing arterial pressure induced by stress-related disorders.

  17. A novel method for detection of preferred retinal locus (PRL) through simple retinal image processing using MATLAB

    NASA Astrophysics Data System (ADS)

    Kalikivayi, V.; Pal, Sudip; Ganesan, A. R.

    2013-09-01

    simple and new technique for detection of `Preferred Retinal Locus' (PRL) in human eye is proposed in this paper. Simple MATLAB algorithms for estimating RGB pixel intensity values of retinal images were used. The technique proved non-existence of `S' cones in Fovea Centralis and also proposes that rods are involved in blue color perception. Retinal images of central vision loss and normal retina were taken for image processing. Blue minimum, Red maximum and Red+Green maximum were the three methods used in detecting PRL. Comparative analyses were also performed for these methods with patient's age and visual acuity.

  18. Retinal artery occlusions in children.

    PubMed

    Dharmasena, Aruna; Wallis, Simon

    2014-01-01

    The purpose of this study is to present a case of RAO in a 13 year old girl with a preceding history of hyperextension of the neck at her hairdressers for a long duration and use of her mobile phone handset resting it against the side of her neck presumably exerting some pressure on carotids during the same time. Materials and methods of this study was reported as case report and review of literature. A 13 year-old girl presented with the left supero-nasal scotoma due to an inferior temporal branch retinal artery occlusion (BRAO). She underwent extensive investigations and no underlying cause was discovered. She gave a history of cervical extension over a long period of time while having the hair coloured twice in the preceding week. She also mentioned that she was using her mobile phone more or less continuously during both these occasions keeping it against her neck. Given the above history it is possible that the pressure on the ipsilateral carotid arteries or the prolong neck extension may have been responsible for the formation of a platelet embolus resulting in the BRAO. In conclusion, although cerebro-vascular accidents due to 'beauty parlor stroke syndrome' (JAMA 269:2085-2086, 1993) have been reported previously it has not been reported in children to our knowledge. On the other hand, 'beauty parlor stroke syndrome' occurs due to a dissection of the vertebral arteries or due to mechanical compression of the vertebral arteries during the prolonged hyperextension of the neck. The central retinal artery originates from the internal carotid circulation and it is highly unlikely for an embolus to enter the retinal circulation from the vertebral arteries. Therefore, the authors favour the possibility that the compulsive use of a mobile phone exerting pressure on the carotid arteries for a long time may have led to the formation of an embolus and subsequent RAO in this case.

  19. Sodium nitrite induces acute central nervous system toxicity in guinea pigs exposed to systemic cell-free hemoglobin

    SciTech Connect

    Buehler, Paul W.; Butt, Omer I.; D'Agnillo, Felice

    2011-06-10

    Highlights: {yields} Toxicological implications associated with the use of NaNO{sub 2} therapy to treat systemic cell-free Hb exposure are not well-defined. {yields} Systemic Hb exposure followed by NaNO{sub 2} infusion induces acute CNS toxicities in guinea pigs. {yields} These CNS effects were not reproduced by the infusion of cell-free Hb or NaNO{sub 2} alone. {yields} NaNO{sub 2}-mediated oxidation of cell-free Hb may play a causative role in the observed CNS changes. -- Abstract: Systemic cell-free hemoglobin (Hb) released via hemolysis disrupts vascular homeostasis, in part, through the scavenging of nitric oxide (NO). Sodium nitrite (NaNO{sub 2}) therapy can attenuate the hypertensive effects of Hb. However, the chemical reactivity of NaNO{sub 2} with Hb may enhance heme- or iron-mediated toxicities. Here, we investigate the effect of NaNO{sub 2} on the central nervous system (CNS) in guinea pigs exposed to systemic cell-free Hb. Intravascular infusion of NaNO{sub 2}, at doses sufficient to alleviate Hb-mediated blood pressure changes, reduced the expression of occludin, but not zona occludens-1 (ZO-1) or claudin-5, in cerebral tight junctions 4 h after Hb infusion. This was accompanied by increased perivascular heme oxygenase-1 expression, neuronal iron deposition, increased astrocyte and microglial activation, and reduced expression of neuron-specific nuclear protein (NeuN). These CNS changes were not observed in animals treated with Hb or NaNO{sub 2} alone. Taken together, these findings suggest that the use of nitrite salts to treat systemic Hb exposure may promote acute CNS toxicity.

  20. Renal extraction and acute effects of glucagon-like peptide-1 on central and renal hemodynamics in healthy men.

    PubMed

    Asmar, Ali; Simonsen, Lene; Asmar, Meena; Madsbad, Sten; Holst, Jens J; Frandsen, Erik; Moro, Cedric; Jonassen, Thomas; Bülow, Jens

    2015-04-15

    The present experiments were performed to elucidate the acute effects of intravenous infusion of glucagon-like peptide (GLP)-1 on central and renal hemodynamics in healthy men. Seven healthy middle-aged men were examined on two different occasions in random order. During a 3-h infusion of either GLP-1 (1.5 pmol·kg⁻¹·min⁻¹) or saline, cardiac output was estimated noninvasively, and intraarterial blood pressure and heart rate were measured continuously. Renal plasma flow, glomerular filtration rate, and uptake/release of hormones and ions were measured by Fick's Principle after catheterization of a renal vein. Subjects remained supine during the experiments. During GLP-1 infusion, both systolic blood pressure and arterial pulse pressure increased by 5±1 mmHg (P=0.015 and P=0.002, respectively). Heart rate increased by 5±1 beats/min (P=0.005), and cardiac output increased by 18% (P=0.016). Renal plasma flow and glomerular filtration rate as well as the clearance of Na⁺ and Li⁺ were not affected by GLP-1. However, plasma renin activity decreased (P=0.037), whereas plasma levels of atrial natriuretic peptide were unaffected. Renal extraction of intact GLP-1 was 43% (P<0.001), whereas 60% of the primary metabolite GLP-1 9-36amide was extracted (P=0.017). In humans, an acute intravenous administration of GLP-1 leads to increased cardiac output due to a simultaneous increase in stroke volume and heart rate, whereas no effect on renal hemodynamics could be demonstrated despite significant extraction of both the intact hormone and its primary metabolite. PMID:25670826

  1. Central review of cytogenetics is necessary for cooperative group correlative and clinical studies of adult acute leukemia: The Cancer and Leukemia Group B experience

    PubMed Central

    Mrózek, Krzysztof; Carroll, Andrew J.; Maharry, Kati; Rao, Kathleen W.; Patil, Shivanand R.; Pettenati, Mark J.; Watson, Michael S.; Arthur, Diane C.; Tantravahi, Ramana; Heerema, Nyla A.; Koduru, Prasad R. K.; Block, AnneMarie W.; Qumsiyeh, Mazin B.; Edwards, Colin G.; Sterling, Lisa J.; Holland, Kelsi B.; Bloomfield, Clara D.

    2009-01-01

    The Cancer and Leukemia Group B has performed central review of karyotypes submitted by institutional cytogenetics laboratories from patients with acute myeloid (AML) and acute lymphoblastic (ALL) leukemia since 1986. We assessed the role of central karyotype review in maintaining accurate, high quality cytogenetic data for clinical and translational studies using two criteria: the proportion of karyotypes rejected (i.e. inadequate), and, among accepted (i.e. adequate) cases, the proportion of karyotypes whose interpretation was changed on central karyotype review. We compared the first four years during which central karyotype review was performed with a recent four-year period and found that the proportion of rejected samples decreased significantly for both AML and ALL. However, during the latter period, central karyotype reviews still found 8% of AML and 16% of ALL karyotypes inadequate. Among adequate cases, the karyotype was revised in 26% of both AML and ALL samples. Some revisions resulted in changing the patients’ assignment to particular World Health Organization diagnostic categories and/or moving patients from one prognostic group to another. Overall, when both data on rejection rates and data on karyotype revisions made in accepted cases were considered together, 32% of AML and 38% of ALL samples submitted were either rejected or revised on central karyotype review during the recent 4-year period. These data underscore the necessity of continued central karyotype review in multi-institutional cooperative group studies. PMID:18636143

  2. Finite element modeling of retinal prosthesis mechanics

    NASA Astrophysics Data System (ADS)

    Basinger, B. C.; Rowley, A. P.; Chen, K.; Humayun, M. S.; Weiland, J. D.

    2009-10-01

    Epiretinal prostheses used to treat degenerative retina diseases apply stimulus via an electrode array fixed to the ganglion cell side of the retina. Mechanical pressure applied by these arrays to the retina, both during initial insertion and throughout chronic use, could cause sufficient retinal damage to reduce the device's effectiveness. In order to understand and minimize potential mechanical damage, we have used finite element analysis to model mechanical interactions between an electrode array and the retina in both acute and chronic loading configurations. Modeling indicates that an acute tacking force distributes stress primarily underneath the tack site and heel edge of the array, while more moderate chronic stresses are distributed more evenly underneath the array. Retinal damage in a canine model chronically implanted with a similar array occurred in correlating locations, and model predictions correlate well with benchtop eyewall compression tests. This model provides retinal prosthesis researchers with a tool to optimize the mechanical electrode array design, but the techniques used here represent a unique effort to combine a modifiable device and soft biological tissues in the same model and those techniques could be extended to other devices that come into mechanical contact with soft neural tissues.

  3. Acute Cerebrovascular Radiation Syndrome: Radiation Neurotoxicity , mechanisms of CNS radiation injury, advanced countermeasures for Radiation Protection of Central Nervous System.

    NASA Astrophysics Data System (ADS)

    Popov, Dmitri; Jones, Jeffrey; Maliev, Slava

    Key words: Cerebrovascular Acute Radiation Syndrome (Cv ARS), Radiation Neurotoxins (RNT), Neurotransmitters, Radiation Countermeasures, Antiradiation Vaccine (ArV), Antiradiation Blocking Antibodies, Antiradiation Antidote. Psychoneuroimmunology, Neurotoxicity. ABSTRACT: To review the role of Radiation Neurotoxins in triggering, developing of radiation induced central nervous system injury. Radiation Neurotoxins - rapidly acting blood toxic lethal agent, which activated after irradiation and concentrated, circulated in interstitial fluid, lymph, blood with interactions with cell membranes, receptors and cell compartments. Radiation Neurotoxins - biological molecules with high enzymatic activity and/or specific lipids and activated or modified after irradiation. The Radiation Neurotoxins induce increased permeability of blood vessels, disruption of the blood-brain barrier, blood-cerebrospinal fluid (CSF) barrier and developing severe disorder of blood macro- and micro-circulation. Principles of Radiation Psychoneuro-immunology and Psychoneuro-allergology were applied for determination of pathological processes developed after irradiation or selective administration of Radiation Neurotoxins to radiation naïve mammals. Effects of radiation and exposure to radiation can develop severe irreversible abnormalities of Central Nervous System, brain structures and functions. Antiradiation Vaccine - most effective, advanced methods of protection, prevention, mitigation and treatment and was used for of Acute Radiation Syndromes and elaboration of new technology for immune-prophylaxis and immune-protection against ϒ, Heavy Ion, Neutron irradiation. Results of experiments suggested that blocking, antitoxic, antiradiation antibodies can significantly reduce toxicity of Radiation Toxins. New advanced technology include active immune-prophylaxis with Antiradiation Vaccine and Antiradiation therapy that included specific blocking antibodies to Radiation Neurotoxins

  4. Progressive outer retinal necrosis-like retinitis in immunocompetent hosts.

    PubMed

    Chawla, Rohan; Tripathy, Koushik; Gogia, Varun; Venkatesh, Pradeep

    2016-01-01

    We describe two young immunocompetent women presenting with bilateral retinitis with outer retinal necrosis involving posterior pole with centrifugal spread and multifocal lesions simulating progressive outer retinal necrosis (PORN) like retinitis. Serology was negative for HIV and CD4 counts were normal; however, both women were on oral steroids at presentation for suspected autoimmune chorioretinitis. The retinitis in both eyes responded well to oral valaciclovir therapy. However, the eye with the more fulminant involvement developed retinal detachment with a loss of vision. Retinal atrophy was seen in the less involved eye with preservation of vision. Through these cases, we aim to describe a unique evolution of PORN-like retinitis in immunocompetent women, which was probably aggravated by a short-term immunosuppression secondary to oral steroids. PMID:27511757

  5. Progressive outer retinal necrosis-like retinitis in immunocompetent hosts.

    PubMed

    Chawla, Rohan; Tripathy, Koushik; Gogia, Varun; Venkatesh, Pradeep

    2016-08-10

    We describe two young immunocompetent women presenting with bilateral retinitis with outer retinal necrosis involving posterior pole with centrifugal spread and multifocal lesions simulating progressive outer retinal necrosis (PORN) like retinitis. Serology was negative for HIV and CD4 counts were normal; however, both women were on oral steroids at presentation for suspected autoimmune chorioretinitis. The retinitis in both eyes responded well to oral valaciclovir therapy. However, the eye with the more fulminant involvement developed retinal detachment with a loss of vision. Retinal atrophy was seen in the less involved eye with preservation of vision. Through these cases, we aim to describe a unique evolution of PORN-like retinitis in immunocompetent women, which was probably aggravated by a short-term immunosuppression secondary to oral steroids.

  6. Laser-induced retinal nerve fiber layer injury in the nonhuman primate

    NASA Astrophysics Data System (ADS)

    Zwick, Harry; Belkin, Michael; Zuclich, Joseph A.; Lund, David J.; Schuschereba, Steven T.; Scales, David K.

    1996-04-01

    We have evaluated the acute effects of Argon laser injury to the retinal nerve fiber layer (NFL) in the non-human primate. Single Argon laser exposures of 150 millijoules were employed to induce retinal NFL injury. Retinal NFL injury is not acute; unlike its parallel in retinal disease it has two components that emanate from the acute retinal injury site. The ascending component is more visible, primarily because it is ascending toward the disk, representing ganglion cell axons cut off from their nutrient base, the ganglion cell body; the descending component may require up to 3 weeks to develop. Its characterization depends on the distribution of retinal NFL and the slower degeneration of the ganglion cell bodies. Fluorescein angiography suggest a retinal capillary loss that occurs in the capillary bed of the retinal NFL defect. It may reflect a reduced capillary vascular requirement of the NFL as well as a possible reduction of activity in the axonal transport mechanisms in the ascending NFL defect.

  7. Photovoltaic retinal prosthesis

    NASA Astrophysics Data System (ADS)

    Loudin, James; Mathieson, Keith; Kamins, Ted; Wang, Lele; Galambos, Ludwig; Huie, Philip; Sher, Alexander; Harris, James; Palanker, Daniel

    2011-03-01

    Electronic retinal prostheses seek to restore sight to patients suffering from retinal degenerative disorders. Implanted electrode arrays apply patterned electrical stimulation to surviving retinal neurons, producing visual sensations. All current designs employ inductively coupled coils to transmit power and/or data to the implant. We present here the design and initial testing of a photovoltaic retinal prosthesis fabricated with a pixel density of up to 177 pixels/mm2. Photodiodes within each pixel of the subretinal array directly convert light to stimulation current, avoiding the use of bulky coil implants, decoding electronics, and wiring, and thereby reducing surgical complexity. A goggles-mounted camera captures the visual scene and transmits the data stream to a pocket processor. The resulting images are projected into the eyes by video goggles using pulsed, near infrared (~900 nm) light. Prostheses with three pixel densities (15, 55, and 177 pix/mm2) are being fabricated, and tests indicate a charge injection limit of 1.62 mC/cm2 at 25Hz. In vitro tests of the photovoltaic retinal stimulation using a 512-element microelectrode array have recorded stimulated spikes from the ganglion cells, with latencies in the 1-100ms range, and with peak irradiance stimulation thresholds varying from 0.1 to 1 mW/mm2. With 1ms pulses at 25Hz the average irradiance is more than 100 times below the IR retinal safety limit. Elicited retinal response disappeared upon the addition of synaptic blockers, indicating that the inner retina is stimulated rather than the ganglion cells directly, and raising hopes that the prosthesis will preserve some of the retina's natural signal processing.

  8. Improving the therapeutic window of retinal photocoagulation by spatial and temporal modulation of the laser beam

    NASA Astrophysics Data System (ADS)

    Sramek, Christopher; Leung, Loh-Shan; Leng, Theodore; Brown, Jefferson; Paulus, Yannis M.; Schuele, Georg; Palanker, Daniel

    2011-02-01

    Decreasing the pulse duration helps confine damage, shorten treatment time, and minimize pain during retinal photocoagulation. However, the safe therapeutic window (TW), the ratio of threshold powers for thermomechanical rupture of Bruch's membrane and mild coagulation, also decreases with shorter exposures. Two potential approaches toward increasing TW are investigated: (a) decreasing the central irradiance of the laser beam and (b) temporally modulating the pulse. An annular beam with adjustable central irradiance was created by coupling a 532-nm laser into a 200-μm core multimode optical fiber at a 4-7 deg angle to normal incidence. Pulse shapes were optimized using a computational model, and a waveform generator was used to drive a PASCAL photocoagulator (532 nm), producing modulated laser pulses. Acute thresholds for mild coagulation and rupture were measured in Dutch-Belted rabbit in vivo with an annular beam (154-163 μm retinal diameter) and modulated pulse (132 μm, uniform irradiance ``flat-top'' beam) with 2-50 ms pulse durations. Thresholds with conventional constant-power pulse and a flat-top beam were also determined. Both annular beam and modulated pulse provided a 28% increase in TW at 10-ms duration, affording the same TW as 20-ms pulses with conventional parameters.

  9. Presentation of Complex Homozygous Allele in ABCA4 Gene in a Patient with Retinitis Pigmentosa.

    PubMed

    Audere, Māreta; Rutka, Katrīna; Šepetiene, Svetlana; Lāce, Baiba

    2015-01-01

    Retinitis pigmentosa is a degenerative retinal disease characterized by progressive photoreceptor damage, which causes loss of peripheral and night vision and the development of tunnel vision and may result in loss of central vision. This study describes a patient with retinitis pigmentosa caused by a mutation in the ABCA4 gene with complex allele c.1622T>C, p.L541P; c.3113C>T, p.A1038V in homozygous state. PMID:26229699

  10. Vitreal Oxygenation in Retinal Ischemia Reperfusion

    PubMed Central

    Abdallah, Walid; Ameri, Hossein; Barron, Ernesto; Chader, Gerald J.; Greenbaum, Elias; Hinton, David R.

    2011-01-01

    Purpose. To study the feasibility of anterior vitreal oxygenation for the treatment of acute retinal ischemia. Methods. Twenty rabbits were randomized into an oxygenation group, a sham treatment group, and a no treatment group. Baseline electroretinography (ERG) and preretinal oxygen (Po2) measurements were obtained 3 to 5 days before surgery. Intraocular pressure was raised to 100 mm Hg for 90 minutes and then normalized. The oxygenation group underwent vitreal oxygenation for 30 minutes using intravitreal electrodes. The sham treatment group received inactive electrodes for 30 minutes while there was no intervention for the no treatment group. Preretinal Po2 in the posterior vitreous was measured 30 minutes after intervention or 30 minutes after reperfusion (no treatment group) and on postoperative days (d) 3, 6, 9, and 12. On d14, rabbits underwent ERG and were euthanatized. Results. Mean final (d12) Po2 was 10.64 ± 0.77 mm Hg for the oxygenation group, 2.14 ± 0.61 mm Hg for the sham group, and 1.98 ± 0.63 mm Hg for the no treatment group. On ERG, scotopic b-wave amplitude was significantly preserved in the oxygenation group compared with the other two groups. Superoxide dismutase assay showed higher activity in the operated eyes than in the nonoperated control eyes in the sham treatment group and no treatment group only. Histopathology showed preservation of retinal architecture and choroidal vasculature in the oxygenation group, whereas the sham-treated and nontreated groups showed retinal thinning and choroidal atrophy. Conclusions. In severe total ocular ischemia, anterior vitreal oxygenation supplies enough oxygen to penetrate the retinal thickness, resulting in rescue of the RPE/choriocapillaris that continues to perfuse, hence sparing the retinal tissue from damage. PMID:21051734

  11. In Vivo Imaging of Retinal Hypoxia in a Model of Oxygen-Induced Retinopathy

    PubMed Central

    Uddin, Md. Imam; Evans, Stephanie M.; Craft, Jason R.; Capozzi, Megan E.; McCollum, Gary W.; Yang, Rong; Marnett, Lawrence J.; Uddin, Md. Jashim; Jayagopal, Ashwath; Penn, John S.

    2016-01-01

    Ischemia-induced hypoxia elicits retinal neovascularization and is a major component of several blinding retinopathies such as retinopathy of prematurity (ROP), diabetic retinopathy (DR) and retinal vein occlusion (RVO). Currently, noninvasive imaging techniques capable of detecting and monitoring retinal hypoxia in living systems do not exist. Such techniques would greatly clarify the role of hypoxia in experimental and human retinal neovascular pathogenesis. In this study, we developed and characterized HYPOX-4, a fluorescence-imaging probe capable of detecting retinal-hypoxia in living animals. HYPOX-4 dependent in vivo and ex vivo imaging of hypoxia was tested in a mouse model of oxygen-induced retinopathy (OIR). Predicted patterns of retinal hypoxia were imaged by HYPOX-4 dependent fluorescence activity in this animal model. In retinal cells and mouse retinal tissue, pimonidazole-adduct immunostaining confirmed the hypoxia selectivity of HYPOX-4. HYPOX-4 had no effect on retinal cell proliferation as indicated by BrdU assay and exhibited no acute toxicity in retinal tissue as indicated by TUNEL assay and electroretinography (ERG) analysis. Therefore, HYPOX-4 could potentially serve as the basis for in vivo fluorescence-based hypoxia-imaging techniques, providing a tool for investigators to understand the pathogenesis of ischemic retinopathies and for physicians to address unmet clinical needs. PMID:27491345

  12. Peripheral retinal non-perfusion and treatment response in branch retinal vein occlusion

    PubMed Central

    Abri Aghdam, Kaveh; Reznicek, Lukas; Soltan Sanjari, Mostafa; Framme, Carsten; Bajor, Anna; Klingenstein, Annemarie; Kernt, Marcus; Seidensticker, Florian

    2016-01-01

    AIM To evaluate the association between the size of peripheral retinal non-perfusion and the number of intravitreal ranibizumab injections in patients with treatment-naive branch retinal vein occlusion (BRVO) and macular edema. METHODS A total of 53 patients with treatment-naive BRVO and macular edema were included. Each patient underwent a full ophthalmologic examination including optical coherence tomography (OCT) imaging and ultra wide-field fluorescein angiography (UWFA). Monthly intravitreal ranibizumab injections were applied according to the recommendations of the German Ophthalmological Society. Two independent, masked graders quantified the areas of peripheral retinal non-perfusion. RESULTS Intravitreal injections improved best-corrected visual acuity (BCVA) significantly from 22.23±16.33 Early Treatment of Diabetic Retinopathy Study (ETDRS) letters to 36.23±15.19 letters (P<0.001), and mean central subfield thickness significantly reduced from 387±115 µm to 321±115 µm (P=0.01). Mean number of intravitreal ranibizumab injections was 3.61±1.56. The size of retinal non-perfusion correlated significantly with the number of intravitreal ranibizumab injections (R=0.724, P<0.001). CONCLUSION Peripheral retinal non-perfusion in patients with BRVO associates significantly with intravitreal ranibizumab injections in patients with BRVO and macular edema. PMID:27366688

  13. Central estrogenic pathways protect against the depressant action of acute nicotine on reflex tachycardia in female rats

    SciTech Connect

    El-Mas, Mahmoud M. Fouda, Mohamed A.; El-gowilly, Sahar M.; Saad, Evan I.

    2012-02-01

    We have previously shown that acute exposure of male rats to nicotine preferentially attenuates baroreceptor-mediated control of reflex tachycardia in contrast to no effect on reflex bradycardia. Here, we investigated whether female rats are as sensitive as their male counterparts to the baroreflex depressant effect of nicotine and whether this interaction is modulated by estrogen. Baroreflex curves relating reflex chronotropic responses evoked by i.v. doses (1–16 μg/kg) of phenylephrine (PE) or sodium nitroprusside (SNP), were constructed in conscious freely moving proestrus, ovariectomized (OVX), and estrogen (50 μg/kg/day s.c., 5 days)-replaced OVX (OVXE{sub 2}) rats. Slopes of the curves were taken as a measure of baroreflex sensitivity (BRS{sub PE} and BRS{sub SNP}). Nicotine (100 μg/kg i.v.) reduced BRS{sub SNP} in OVX rats but not in proestrus or OVXE{sub 2} rats. The attenuation of reflex tachycardia by nicotine was also evident in diestrus rats, which exhibited plasma estrogen levels similar to those of OVX rats. BRS{sub PE} was not affected by nicotine in all rat preparations. Experiments were then extended to determine whether central estrogenic receptors modulate the nicotine–BRS{sub SNP} interaction. Intracisteral (i.c.) treatment of OVX rats with estrogen sulfate (0.2 μg/rat) abolished the BRS{sub SNP} attenuating effect of i.v. nicotine. This protective effect of estrogen disappeared when OVX rats were pretreated with i.c. ICI 182,780 (50 μg/rat, selective estrogen receptor antagonist). Together, these findings suggest that central neural pools of estrogen receptors underlie the protection offered by E{sub 2} against nicotine-induced baroreceptor dysfunction in female rats. -- Highlights: ► Estrogen protects against the depressant effect of nicotine on reflex tachycardia. ► The baroreflex response and estrogen status affect the nicotine–BRS interaction. ► The protection offered by estrogen is mediated via central estrogen receptors.

  14. Retinal and visual system: occupational and environmental toxicology.

    PubMed

    Fox, Donald A

    2015-01-01

    Occupational chemical exposure often results in sensory systems alterations that occur without other clinical signs or symptoms. Approximately 3000 chemicals are toxic to the retina and central visual system. Their dysfunction can have immediate, long-term, and delayed effects on mental health, physical health, and performance and lead to increased occupational injuries. The aims of this chapter are fourfold. First, provide references on retinal/visual system structure, function, and assessment techniques. Second, discuss the retinal features that make it especially vulnerable to toxic chemicals. Third, review the clinical and corresponding experimental data regarding retinal/visual system deficits produced by occupational toxicants: organic solvents (carbon disulfide, trichloroethylene, tetrachloroethylene, styrene, toluene, and mixtures) and metals (inorganic lead, methyl mercury, and mercury vapor). Fourth, discuss occupational and environmental toxicants as risk factors for late-onset retinal diseases and degeneration. Overall, the toxicants altered color vision, rod- and/or cone-mediated electroretinograms, visual fields, spatial contrast sensitivity, and/or retinal thickness. The findings elucidate the importance of conducting multimodal noninvasive clinical, electrophysiologic, imaging and vision testing to monitor toxicant-exposed workers for possible retinal/visual system alterations. Finally, since the retina is a window into the brain, an increased awareness and understanding of retinal/visual system dysfunction should provide additional insight into acquired neurodegenerative disorders. PMID:26563796

  15. Vitamin A derivatives as treatment options for retinal degenerative diseases.

    PubMed

    Perusek, Lindsay; Maeda, Tadao

    2013-07-12

    The visual cycle is a sequential enzymatic reaction for vitamin A, all-trans-retinol, occurring in the outer layer of the human retina and is essential for the maintenance of vision. The central source of retinol is derived from dietary intake of both retinol and pro-vitamin A carotenoids. A series of enzymatic reactions, located in both the photoreceptor outer segment and the retinal pigment epithelium, transform retinol into the visual chromophore 11-cis-retinal, regenerating visual pigments. Retina specific proteins carry out the majority of the visual cycle, and any significant interruption in this sequence of reactions is capable of causing varying degrees of blindness. Among these important proteins are Lecithin:retinol acyltransferase (LRAT) and retinal pigment epithelium-specific 65-kDa protein (RPE65) known to be responsible for esterification of retinol to all-trans-retinyl esters and isomerization of these esters to 11-cis-retinal, respectively. Deleterious mutations in these genes are identified in human retinal diseases that cause blindness, such as Leber congenital amaurosis (LCA) and retinitis pigmentosa (RP). Herein, we discuss the pathology of 11-cis-retinal deficiency caused by these mutations in both animal disease models and human patients. We also review novel therapeutic strategies employing artificial visual chromophore 9-cis-retinoids which have been employed in clinical trials involving LCA patients.

  16. Vitamin A Derivatives as Treatment Options for Retinal Degenerative Diseases

    PubMed Central

    Perusek, Lindsay; Maeda, Tadao

    2013-01-01

    The visual cycle is a sequential enzymatic reaction for vitamin A, all-trans-retinol, occurring in the outer layer of the human retina and is essential for the maintenance of vision. The central source of retinol is derived from dietary intake of both retinol and pro-vitamin A carotenoids. A series of enzymatic reactions, located in both the photoreceptor outer segment and the retinal pigment epithelium, transform retinol into the visual chromophore 11-cis-retinal, regenerating visual pigments. Retina specific proteins carry out the majority of the visual cycle, and any significant interruption in this sequence of reactions is capable of causing varying degrees of blindness. Among these important proteins are Lecithin:retinol acyltransferase (LRAT) and retinal pigment epithelium-specific 65-kDa protein (RPE65) known to be responsible for esterification of retinol to all-trans-retinyl esters and isomerization of these esters to 11-cis-retinal, respectively. Deleterious mutations in these genes are identified in human retinal diseases that cause blindness, such as Leber congenital amaurosis (LCA) and retinitis pigmentosa (RP). Herein, we discuss the pathology of 11-cis-retinal deficiency caused by these mutations in both animal disease models and human patients. We also review novel therapeutic strategies employing artificial visual chromophore 9-cis-retinoids which have been employed in clinical trials involving LCA patients. PMID:23857173

  17. A continuum model of retinal electrical stimulation

    NASA Astrophysics Data System (ADS)

    Joarder, Saiful A.; Abramian, Miganoosh; Suaning, Gregg J.; Lovell, Nigel H.; Dokos, Socrates

    2011-10-01

    A continuum mathematical model of retinal electrical stimulation is described. The model is represented by a passive vitreous domain, a thin layer of active retinal ganglion cell (RGC) tissue adjacent to deeper passive neural layers of the retina, the retinal pigmented epithelium (RPE) and choroid thus ending at the sclera. To validate the model, in vitro epiretinal responses to stimuli from 50 µm disk electrodes, arranged in a hexagonal mosaic, were recorded from rabbit retinas. 100 µs/phase anodic-first biphasic current pulses were delivered to the retinal surface in both the mathematical model and experiments. RGC responses were simulated and recorded using extracellular microelectrodes. The model's epiretinal thresholds compared favorably with the in vitro data. In addition, simulations showed that single-return bipolar electrodes recruited a larger area of the retina than twin-return or six-return electrodes arranged in a hexagonal layout in which a central stimulating electrode is surrounded by six, eqi-spaced returns. Simulations were also undertaken to investigate the patterns of RGC activation in an anatomically-accurate model of the retina, as well as RGC activation patterns for subretinal and suprachoroidal bipolar stimulation. This paper was originally submitted for the special issue containing contributions from the Sixth Biennial Research Congress of The Eye and the Chip.

  18. Retinal pigment epithelial cell proliferation

    PubMed Central

    Temple, Sally

    2015-01-01

    The human retinal pigment epithelium forms early in development and subsequently remains dormant, undergoing minimal proliferation throughout normal life. Retinal pigment epithelium proliferation, however, can be activated in disease states or by removing retinal pigment epithelial cells into culture. We review the conditions that control retinal pigment epithelial proliferation in culture, in animal models and in human disease and interpret retinal pigment epithelium proliferation in context of the recently discovered retinal pigment epithelium stem cell that is responsible for most in vitro retinal pigment epithelial proliferation. Retinal pigment epithelial proliferation-mediated wound repair that occurs in selected macular diseases is contrasted with retinal pigment epithelial proliferation-mediated fibroblastic scar formation that underlies proliferative vitreoretinopathy. We discuss the role of retinal pigment epithelial proliferation in age-related macular degeneration which is reparative in some cases and destructive in others. Macular retinal pigment epithelium wound repair and regression of choroidal neovascularization are more pronounced in younger than older patients. We discuss the possibility that the limited retinal pigment epithelial proliferation and latent wound repair in older age-related macular degeneration patients can be stimulated to promote disease regression in age-related macular degeneration. PMID:26041390

  19. Probabilistic retinal vessel segmentation

    NASA Astrophysics Data System (ADS)

    Wu, Chang-Hua; Agam, Gady

    2007-03-01

    Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.

  20. Bioelectronic retinal prosthesis

    NASA Astrophysics Data System (ADS)

    Weiland, James D.

    2016-05-01

    Retinal prosthesis have been translated to clinical use over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa and one device is in clinical trials for treatment of age-related macular degeneration. These devices provide partial sight restoration and patients use this improved vision in their everyday lives to navigate and to detect large objects. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. In particular, current retinal prostheses do not provide peripheral visions due to technical and surgical limitations, thus limiting the effectiveness of the treatment. This paper reviews recent results from human implant patients and presents technical approaches for peripheral vision.

  1. Pathway to Retinal Oximetry

    PubMed Central

    Beach, James

    2014-01-01

    Events and discoveries in oxygen monitoring over the past two centuries are presented as the background from which oximetry of the human retina evolved. Achievements and the people behind them are discussed, showing parallels between the work in tissue measurements and later in the eye. Developments in the two-wavelength technique for oxygen saturation measurements in retinal vessels are shown to exploit the forms of imaging technology available over time. The last section provides a short summary of the recent research in retinal diseases using vessel oximetry. PMID:25237591

  2. Retinal lesions in septicemia.

    PubMed

    Neudorfer, M; Barnea, Y; Geyer, O; Siegman-Igra, Y

    1993-12-15

    We explored the association between septicemia and specific retinal lesions in a prospective controlled study. Hemorrhages, cotton-wool spots, or Roth's spots were found in 24 of 101 septicemic patients (24%), compared to four of 99 age- and gender-matched control patients (4%) (P = .0002). There was no significant association between types of organisms or focus of infection and the presence of specific lesions. Histologic examination of affected eyes disclosed cytoid bodies in the nerve fiber layer without inflammation. A definite association between septicemia and retinal lesions was found and indicates the need for routine ophthalmoscopy in septicemic patients. PMID:8250076

  3. Hospital Performance Indicators and Their Associated Factors in Acute Child Poisoning at a Single Poison Center, Central Saudi Arabia.

    PubMed

    Alanazi, Menyfah Q; Al-Jeriasy, Majed I; Al-Assiri, Mohammed H; Afesh, Lara Y; Alhammad, Fahad; Salam, Mahmoud

    2015-12-01

    Admission rate and length of stay (LOS) are two hospital performance indicators that affect the quality of care, patients' satisfaction, bed turnover, and health cost expenditures. The aim of the study was to identify factors associated with higher admission rates and extended average LOS among acutely poisoned children at a single poison center, central Saudi Arabia.This is a cross-sectional, poison and medical chart review between 2009 and 2011. Exposures were child characteristics, that is, gender, age, body mass index (BMI), health history, and Canadian 5-level triage scale. Poison incident characteristics were, that is, type, exposure route, amount, form, home remedy, and arrival time to center. Admission status and LOS were obtained from records. Chronic poisoning, plant allergies, and venomous bites were excluded. Bivariate and regression analyses were applied. Significance at P < 0.05.Of the 315 eligible cases, (72%) were toddlers with equal gender distribution, (58%) had normal BMI, and (77%) were previously healthy. Poison substances were pharmaceutical drugs (63%) versus chemical products (37%). Main exposure route was oral (98%). Home remedy was observed in (21.9%), which were fluids, solutes, and/or gag-induced vomiting. Almost (52%) arrived to center >1 h. Triage levels: non-urgent cases (58%), less urgent (11%), urgent (18%), emergency (12%), resuscitative (1%). Admission rate was (20.6%) whereas av. LOS was 13 ± 22 h. After adjusting and controlling for confounders, older children (adj.OR = 1.19) and more critical triage levels (adj.OR = 1.35) were significantly associated with higher admission rates compared to younger children and less critical triage levels (adj.P = 0.006) and (adj.P = 0.042) respectively. Home remedy prior arrival was significantly associated with higher av. LOS (Beta = 9.48, t = 2.99), compared to those who directly visited the center, adj.P = 0.003.Hospital administrators are cautioned

  4. Hospital Performance Indicators and Their Associated Factors in Acute Child Poisoning at a Single Poison Center, Central Saudi Arabia.

    PubMed

    Alanazi, Menyfah Q; Al-Jeriasy, Majed I; Al-Assiri, Mohammed H; Afesh, Lara Y; Alhammad, Fahad; Salam, Mahmoud

    2015-12-01

    Admission rate and length of stay (LOS) are two hospital performance indicators that affect the quality of care, patients' satisfaction, bed turnover, and health cost expenditures. The aim of the study was to identify factors associated with higher admission rates and extended average LOS among acutely poisoned children at a single poison center, central Saudi Arabia.This is a cross-sectional, poison and medical chart review between 2009 and 2011. Exposures were child characteristics, that is, gender, age, body mass index (BMI), health history, and Canadian 5-level triage scale. Poison incident characteristics were, that is, type, exposure route, amount, form, home remedy, and arrival time to center. Admission status and LOS were obtained from records. Chronic poisoning, plant allergies, and venomous bites were excluded. Bivariate and regression analyses were applied. Significance at P < 0.05.Of the 315 eligible cases, (72%) were toddlers with equal gender distribution, (58%) had normal BMI, and (77%) were previously healthy. Poison substances were pharmaceutical drugs (63%) versus chemical products (37%). Main exposure route was oral (98%). Home remedy was observed in (21.9%), which were fluids, solutes, and/or gag-induced vomiting. Almost (52%) arrived to center >1 h. Triage levels: non-urgent cases (58%), less urgent (11%), urgent (18%), emergency (12%), resuscitative (1%). Admission rate was (20.6%) whereas av. LOS was 13 ± 22 h. After adjusting and controlling for confounders, older children (adj.OR = 1.19) and more critical triage levels (adj.OR = 1.35) were significantly associated with higher admission rates compared to younger children and less critical triage levels (adj.P = 0.006) and (adj.P = 0.042) respectively. Home remedy prior arrival was significantly associated with higher av. LOS (Beta = 9.48, t = 2.99), compared to those who directly visited the center, adj.P = 0.003.Hospital administrators are cautioned

  5. Preparation of embryonic retinal explants to study CNS neurite growth.

    PubMed

    Hanea, Sonia T; Shanmugalingam, Ushananthini; Fournier, Alyson E; Smith, Patrice D

    2016-05-01

    This protocol outlines the preparation of embryonic mouse retinal explants, which provides an effective technique to analyze neurite outgrowth in central nervous system (CNS) neurons. This validated ex vivo system, which displays limited neuronal death, is highly reproducible and particularly amenable to manipulation. Our previously published studies involving embryonic chick or adult mouse retinal explants were instrumental in the preparation of this protocol; aspects of these previous techniques were combined, adopted and optimized. This protocol thus permits more efficient analysis of neurite growth. Briefly, the retina is dissected from the embryonic mouse eye using precise techniques that take into account the small size of the embryonic eye. The approach applied ensures that the retinal ganglion cell (RGC) layer faces the adhesion substrate on coated cover slips. Neurite growth is clear, well-delineated and readily quantifiable. These retinal explants can therefore be used to examine the neurite growth effects elicited by potential therapeutic agents. PMID:27072342

  6. Retinal compensatory changes after light damage in albino mice

    PubMed Central

    Montalbán-Soler, Luis; Alarcón-Martínez, Luis; Jiménez-López, Manuel; Salinas-Navarro, Manuel; Galindo-Romero, Caridad; Bezerra de Sá, Fabrízio; García-Ayuso, Diego; Avilés-Trigueros, Marcelino; Vidal-Sanz, Manuel; Agudo-Barriuso, Marta

    2012-01-01

    Purpose To investigate the anatomic and functional changes triggered by light exposure in the albino mouse retina and compare them with those observed in the albino rat. Methods BALB/c albino mice were exposed to 3,000 lx of white light during 24 h and their retinas analyzed from 1 to 180 days after light exposure (ALE). Left pupil mydriasis was induced with topical atropine. Retinal function was analyzed by electroretinographic (ERG) recording. To assess retinal degeneration, hematoxylin and eosin staining, the TdT-mediated dUTP nick-end labeling (TUNEL) technique, and quantitative immunohistofluorescence for synaptophysin and protein kinase Cα (PKCα) were used in cross sections. Intravenous injection of horseradish peroxidase and Fluoro-Gold™ tracing were used in whole-mounted retinas to study the retinal vasculature and the retinal ganglion cell (RGC) population, respectively. Results Light exposure caused apoptotic photoreceptor death in the central retina. This death was more severe in the dorsal than in the ventral retina, sparing the periphery. Neither retinal vascular leakage nor retinal ganglion cell death was observed ALE. The electroretinographic a-wave was permanently impaired, while the b-wave decreased but recovered gradually by 180 days ALE. The scotopic threshold responses, associated with the inner retinal function, diminished at first but recovered completely by 14 days ALE. This functional recovery was concomitant with the upregulation of protein kinase Cα and synaptophysin. Similar results were obtained in both eyes, irrespective of mydriasis. Conclusions In albino mice, light exposure induces substantial retinal damage, but the surviving photoreceptors, together with compensatory morphological/molecular changes, allow an important restoration of the retinal function. PMID:22509098

  7. Macular pigment optical density is related to serum lutein in retinitis pigmentosa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Purpose: To determine whether macular pigment optical density (MPOD) is related to the degree of cystoid macular edema (CME) in patients with retinitis pigmentosa. Methods: We measured MPOD with heterochromatic flicker photometry and central foveal retinal thickness with optical coherence tomography...

  8. Outcomes and Acute Toxicities of Proton Therapy for Pediatric Atypical Teratoid/Rhabdoid Tumor of the Central Nervous System

    SciTech Connect

    McGovern, Susan L.; Okcu, M. Fatih; Munsell, Mark F.; Kumbalasseriyil, Nancy; Grosshans, David R.; McAleer, Mary F.; Chintagumpala, Murali; Khatua, Soumen; Mahajan, Anita

    2014-12-01

    Purpose: Atypical teratoid/rhabdoid tumor (AT/RT) of the central nervous system is a rare cancer primarily affecting children younger than 5 years old. Because patients are young and receive intensive chemotherapy, there is concern regarding late radiation toxicity, particularly as survival rates improve. Therefore, there is interest in using proton therapy to treat these tumors. This study was undertaken to investigate outcomes and acute toxicities associated with proton therapy for AT/RT. Methods and Materials: The records of 31 patients with AT/RT treated with proton radiation from October 2008 to August 2013 were reviewed. Demographics, treatment characteristics, and outcomes were recorded and analyzed. Results: Median age at diagnosis was 19 months (range, 4-55 months), with a median age at radiation start of 24 months (range, 6-62 months). Seventeen patients received local radiation with a median dose of 50.4 GyRBE (range, 9-54 GyRBE). Fourteen patients received craniospinal radiation; half received 24 GyRBE or less, and half received 30.6 GyRBE or more. For patients receiving craniospinal radiation, the median tumor dose was 54 GyRBE (range, 43.2-55.8 GyRBE). Twenty-seven patients (87%) completed the planned radiation. With median follow-up of 24 months for all patients (range, 3-53 months), median progression-free survival was 20.8 months and median overall survival was 34.3 months. Five patients (16%) developed clinical findings and imaging changes in the brainstem 1 to 4 months after radiation, consistent with radiation reaction; all cases resolved with steroids or bevacizumab. Conclusions: This is the largest report of children with AT/RT treated with proton therapy. Preliminary survival outcomes in this young pediatric population are encouraging compared to historic results, but further study is warranted.

  9. The acute effect of maximal exercise on central and peripheral arterial stiffness indices and hemodynamics in children and adults.

    PubMed

    Melo, Xavier; Fernhall, Bo; Santos, Diana A; Pinto, Rita; Pimenta, Nuno M; Sardinha, Luís B; Santa-Clara, Helena

    2016-03-01

    This study compared the effects of a bout of maximal running exercise on arterial stiffness in children and adults. Right carotid blood pressure and artery stiffness indices measured by pulse wave velocity (PWV), compliance and distensibility coefficients, stiffness index α and β (echo-tracking), contralateral carotid blood pressure, and upper and lower limb and central/aortic PWV (applanation tonometry) were taken at rest and 10 min after a bout of maximal treadmill running in 34 children (7.38 ± 0.38 years) and 45 young adults (25.22 ± 0.91 years) having similar aerobic potential. Two-by-two repeated measures analysis of variance and analysis of covariance were used to detect differences with exercise between groups. Carotid pulse pressure (PP; η(2) = 0.394) increased more in adults after exercise (p < 0.05). Compliance (η(2) = 0.385) decreased in particular in adults and in those with high changes in distending pressure, similarly to stiffness index α and β. Carotid PWV increased more in adults and was related to local changes in PP but not mean arterial pressure (MAP). Stiffness in the lower limbs decreased (η(2) = 0.115) but apparently only in those with small MAP changes (η(2) = 0.111). No significant exercise or group interaction effects were found when variables were adjusted to height. An acute bout of maximal exercise can alter arterial stiffness and hemodynamics in the carotid artery and within the active muscle beds. Arterial stiffness and hemodynamic response to metabolic demands during exercise in children simply reflect their smaller body size and may not indicate a particular physiological difference compared with adults. PMID:26842667

  10. Nanomaterials and Retinal Toxicity

    EPA Science Inventory

    The neuroretina should be considered as a potential site of nanomaterial toxicity. Engineered nanomaterials may reach the retina through three potential routes of exposure including; intra­ vitreal injection of therapeutics; blood-borne delivery in the retinal vasculature an...

  11. Degenerative retinal disorders

    SciTech Connect

    Hollyfield, J.G. Anderson, R.E. LaVail, M.M. . Dept. of Anatomy)

    1987-01-01

    This book contains papers divided among three sections. Some of the paper titles are: Molecular Genetics of Gyrate Atrophy; Molecular Site of Expression and Genetic Interaction of the rd and the rds Loci in the Retina of the Mouse; and Studies on Abnormal Cyclic GMP Metabolism in Animal Models of Retinal Degeneration: Genetic Relationships and Cellular Compartmentalization.

  12. Retinal Vasculitis in Anti-Synthetase Syndrome.

    PubMed

    Donovan, Christopher P; Pecen, Paula E; Baynes, Kimberly; Ehlers, Justis P; Srivastava, Sunil K

    2016-09-01

    A 31-year-old woman with a history of anti-synthetase syndrome-related myositis and interstitial lung disease presented with acute-onset blurry vision and rash on her hands and feet. Visual acuity was hand motion in her right eye and 20/40 in her left eye. Dilated fundus exam showed extensive retinal vasculitis, diffuse intraretinal hemorrhages, and subretinal fluid. Optical coherence tomography revealed significant macular thickening, and fluorescein angiography revealed vascular leakage with peripheral nonperfusion. Aggressive systemic immunosuppression was initiated, with gradual resolution of her disease during 8 months of follow-up. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:874-879.].

  13. Retinal Vasculitis in Anti-Synthetase Syndrome.

    PubMed

    Donovan, Christopher P; Pecen, Paula E; Baynes, Kimberly; Ehlers, Justis P; Srivastava, Sunil K

    2016-09-01

    A 31-year-old woman with a history of anti-synthetase syndrome-related myositis and interstitial lung disease presented with acute-onset blurry vision and rash on her hands and feet. Visual acuity was hand motion in her right eye and 20/40 in her left eye. Dilated fundus exam showed extensive retinal vasculitis, diffuse intraretinal hemorrhages, and subretinal fluid. Optical coherence tomography revealed significant macular thickening, and fluorescein angiography revealed vascular leakage with peripheral nonperfusion. Aggressive systemic immunosuppression was initiated, with gradual resolution of her disease during 8 months of follow-up. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:874-879.]. PMID:27631486

  14. AMIGO3 is an NgR1/p75 co-receptor signalling axon growth inhibition in the acute phase of adult central nervous system injury.

    PubMed

    Ahmed, Zubair; Douglas, Michael R; John, Gabrielle; Berry, Martin; Logan, Ann

    2013-01-01

    Axon regeneration in the injured adult CNS is reportedly inhibited by myelin-derived inhibitory molecules, after binding to a receptor complex comprised of the Nogo-66 receptor (NgR1) and two transmembrane co-receptors p75/TROY and LINGO-1. However, the post-injury expression pattern for LINGO-1 is inconsistent with its proposed function. We demonstrated that AMIGO3 levels were significantly higher acutely than those of LINGO-1 in dorsal column lesions and reduced in models of dorsal root ganglion neuron (DRGN) axon regeneration. Similarly, AMIGO3 levels were raised in the retina immediately after optic nerve crush, whilst levels were suppressed in regenerating optic nerves, induced by intravitreal peripheral nerve implantation. AMIGO3 interacted functionally with NgR1-p75/TROY in non-neuronal cells and in brain lysates, mediating RhoA activation in response to CNS myelin. Knockdown of AMIGO3 in myelin-inhibited adult primary DRG and retinal cultures promoted disinhibited neurite growth when cells were stimulated with appropriate neurotrophic factors. These findings demonstrate that AMIGO3 substitutes for LINGO-1 in the NgR1-p75/TROY inhibitory signalling complex and suggests that the NgR1-p75/TROY-AMIGO3 receptor complex mediates myelin-induced inhibition of axon growth acutely in the CNS. Thus, antagonizing AMIGO3 rather than LINGO-1 immediately after CNS injury is likely to be a more effective therapeutic strategy for promoting CNS axon regeneration when combined with neurotrophic factor administration. PMID:23613963

  15. Unilateral Ischemic Maculopathy Associated with Cytomegalovirus Retinitis in Patients with AIDS: Optical Coherence Tomography Findings

    PubMed Central

    Arevalo, J. Fernando; Garcia, Reinaldo A.; Arevalo, Fernando A.; Fernandez, Carlos F.

    2015-01-01

    To describe the clinical and optical coherence tomography (OCT) characteristics of ischemic maculopathy in two patients with acquired immunodeficiency syndrome (AIDS). Two patients with AIDS and cytomegalovirus (CMV) retinitis developed ischemic maculopathy. Both patients presented with central visual loss and active granular CMV retinitis. The presence of opacification of the superficial retina in the macular area and intraretinal edema suggested the diagnosis. Fluorescein angiography changes were similar in the two cases with enlargement of the foveal avascular zone and late staining of juxtafoveal vessels. OCT changes were suggestive of retinal ischemia: Increased reflectivity from the inner retinal layer and decreased backscattering from the retinal photoreceptors due to fluid and retinal edema. Ischemic maculopathy may cause a severe and permanent decrease in vision in AIDS patients. Fluorescein angiography and OCT should be considered in any patient with AIDS and unexplained visual loss. The mechanism of ischemic maculopathy may be multifactorial. PMID:27051496

  16. Unilateral Ischemic Maculopathy Associated with Cytomegalovirus Retinitis in Patients with AIDS: Optical Coherence Tomography Findings.

    PubMed

    Arevalo, J Fernando; Garcia, Reinaldo A; Arevalo, Fernando A; Fernandez, Carlos F

    2015-01-01

    To describe the clinical and optical coherence tomography (OCT) characteristics of ischemic maculopathy in two patients with acquired immunodeficiency syndrome (AIDS). Two patients with AIDS and cytomegalovirus (CMV) retinitis developed ischemic maculopathy. Both patients presented with central visual loss and active granular CMV retinitis. The presence of opacification of the superficial retina in the macular area and intraretinal edema suggested the diagnosis. Fluorescein angiography changes were similar in the two cases with enlargement of the foveal avascular zone and late staining of juxtafoveal vessels. OCT changes were suggestive of retinal ischemia: Increased reflectivity from the inner retinal layer and decreased backscattering from the retinal photoreceptors due to fluid and retinal edema. Ischemic maculopathy may cause a severe and permanent decrease in vision in AIDS patients. Fluorescein angiography and OCT should be considered in any patient with AIDS and unexplained visual loss. The mechanism of ischemic maculopathy may be multifactorial. PMID:27051496

  17. Neuroprotective therapy for argon-laser-induced retinal injury

    NASA Astrophysics Data System (ADS)

    Belkin, Michael; Rosner, Mordechai; Solberg, Yoram; Turetz, Yosef

    1999-06-01

    Laser photocoagulation treatment of the central retina is often complicated by an immediate side effect of visual impairment, caused by the unavoidable laser-induced destruction of the normal tissue lying adjacent to the lesion and not affected directly by the laser beam. Furthermore, accidental laser injuries are at present untreatable. A neuroprotective therapy for salvaging the normal tissue might enhance the benefit obtained from treatment and allow safe perifoveal photocoagulation. We have developed a rat model for studying the efficacy of putative neuroprotective compounds in ameliorating laser-induced retinal damage. Four compounds were evaluated: the corticosteroid methylprednisolone, the glutamate-receptor blocker MK-801, the anti-oxidant enzyme superoxide dismutase, and the calcim-overload antagonist flunarizine. The study was carried out in two steps: in the first, the histopathological development of retinal laser injuries was studied. Argon laser lesions were inflicted in the retinas of 18 pigmented rats. The animals were sacrificed after 3, 20 or 60 days and their retinal lesions were evaluated under the light microscope. The laser injury mainly involved the outer layers of the retina, where it destroyed significant numbers of photoreceptor cells. Over time, evidence of two major histopathological processes was observed: traction of adjacent nomral retinal cells into the central area of the lesion forming an internal retinal bulging, and a retinal pigmented epithelial proliferative reaction associated with subretinal neovascularization and invations of the retinal lesion site by phagocytes. The neuroprotective effects of each of the four compounds were verified in a second step of the study. For each drug tested, 12 rats were irradiated wtih argon laser inflictions: six of them received the tested agent while the other six were treated with the corresponding vehicle. Twenty days after laser expsoure, the rats were sacrificed and their lesions were

  18. Histone Deacetylase Inhibition Restores Retinal Pigment Epithelium Function in Hyperglycemia

    PubMed Central

    Desjardins, Danielle; Liu, Yueying; Crosson, Craig E.; Ablonczy, Zsolt

    2016-01-01

    In diabetic individuals, macular edema is a major cause of vision loss. This condition is refractory to insulin therapy and has been attributed to metabolic memory. The retinal pigment epithelium (RPE) is central to maintaining fluid balance in the retina, and this function is compromised by the activation of advanced glycation end-product receptors (RAGE). Here we provide evidence that acute administration of the RAGE agonist, glycated-albumin (gAlb) or vascular endothelial growth factor (VEGF), increased histone deacetylase (HDAC) activity in RPE cells. The administration of the class I/II HDAC inhibitor, trichostatin-A (TSA), suppressed gAlb-induced reductions in RPE transepithelial resistance (in vitro) and fluid transport (in vivo). Systemic TSA also restored normal RPE fluid transport in rats with subchronic hyperglycemia. Both gAlb and VEGF increased HDAC activity and reduced acetyl-α-tubulin levels. Tubastatin-A, a relatively specific antagonist of HDAC6, inhibited gAlb-induced changes in RPE cell resistance. These data are consistent with the idea that RPE dysfunction following exposure to gAlb, VEGF, or hyperglycemia is associated with increased HDAC6 activity and decreased acetyl-α-tubulin. Therefore, we propose inhibiting HDAC6 in the RPE as a potential therapy for preserving normal fluid homeostasis in the hyperglycemic retina. PMID:27617745

  19. Histone Deacetylase Inhibition Restores Retinal Pigment Epithelium Function in Hyperglycemia.

    PubMed

    Desjardins, Danielle; Liu, Yueying; Crosson, Craig E; Ablonczy, Zsolt

    2016-01-01

    In diabetic individuals, macular edema is a major cause of vision loss. This condition is refractory to insulin therapy and has been attributed to metabolic memory. The retinal pigment epithelium (RPE) is central to maintaining fluid balance in the retina, and this function is compromised by the activation of advanced glycation end-product receptors (RAGE). Here we provide evidence that acute administration of the RAGE agonist, glycated-albumin (gAlb) or vascular endothelial growth factor (VEGF), increased histone deacetylase (HDAC) activity in RPE cells. The administration of the class I/II HDAC inhibitor, trichostatin-A (TSA), suppressed gAlb-induced reductions in RPE transepithelial resistance (in vitro) and fluid transport (in vivo). Systemic TSA also restored normal RPE fluid transport in rats with subchronic hyperglycemia. Both gAlb and VEGF increased HDAC activity and reduced acetyl-α-tubulin levels. Tubastatin-A, a relatively specific antagonist of HDAC6, inhibited gAlb-induced changes in RPE cell resistance. These data are consistent with the idea that RPE dysfunction following exposure to gAlb, VEGF, or hyperglycemia is associated with increased HDAC6 activity and decreased acetyl-α-tubulin. Therefore, we propose inhibiting HDAC6 in the RPE as a potential therapy for preserving normal fluid homeostasis in the hyperglycemic retina. PMID:27617745

  20. Accidental human laser retinal injuries from military laser systems

    NASA Astrophysics Data System (ADS)

    Stuck, Bruce E.; Zwick, Harry; Molchany, Jerome W.; Lund, David J.; Gagliano, Donald A.

    1996-04-01

    The time course of the ophthalmoscopic and functional consequences of eight human laser accident cases from military laser systems is described. All patients reported subjective vision loss with ophthalmoscopic evidence of retinal alteration ranging from vitreous hemorrhage to retinal burn. Five of the cases involved single or multiple exposures to Q-switched neodymium radiation at close range whereas the other three incidents occur over large ranges. Most exposures were within 5 degrees of the foveola, yet none directly in the foveola. High contrast visual activity improved with time except in the cases with progressive retinal fibrosis between lesion sites or retinal hole formation encroaching the fovea. In one patient the visual acuity recovered from 20/60 at one week to 20/25 in four months with minimal central visual field loss. Most cases showed suppression of high and low spatial frequency contrast sensitivity. Visual field measurements were enlarged relative to ophthalmoscopic lesion size observations. Deep retinal scar formation and retinal traction were evident in two of the three cases with vitreous hemorrhage. In one patient, nerve fiber layer damage to the papillo-macular bundle was clearly evident. Visual performance measured with a pursuit tracking task revealed significant performance loss relative to normal tracking observers even in cases where acuity returned to near normal levels. These functional and performance deficits may reflect secondary effects of parafoveal laser injury.

  1. Bilateral Rhegmatogenous Retinal Detachment during External Beam Radiotherapy.

    PubMed

    Hidaka, Takako; Chuman, Hideki; Nao-I, Nobuhisa

    2016-01-01

    Herein, we report a case of nontraumatic bilateral rhegmatogenous retinal detachment (RRD) during external beam radiotherapy for nonocular tumor, presented as an observational case study in conjunction with a review of the relevant literature. A 65-year-old male was referred to our hospital due to bilateral RRD. He underwent a biopsy for a tumor of the left frontal lobe 4 months prior to presentation, and the tumor had been diagnosed as primary central nerve system B-cell type lymphoma. He received chemotherapy and external beam radiotherapy for 1 month. There were no traumatic episodes. Bilateral retinal detachment occurred during a series of radiotherapies. Simultaneous nontraumatic bilateral retinal detachment is rare. The effects of radiotherapy on ocular functionality, particularly in cases involving retinal adhesion and vitreous contraction, may include RRD. Thus, it is necessary to closely monitor the eyes of patients undergoing radiotherapy, particularly those undergoing surgery for retinal detachment and those with a history of photocoagulation for retinal tears, a relevant family history, or risk factors known to be associated with RRD. PMID:27462261

  2. The Retinal Homeobox (Rx) gene is necessary for retinal regeneration

    PubMed Central

    Martinez-De Luna, Reyna I.; Kelly, Lisa E.; El-Hodiri, Heithem M.

    2011-01-01

    The Retinal Homeobox (Rx) gene is essential for vertebrate eye development. Rx function is required for the specification and maintenance of retinal progenitor cells (RPCs). Loss of Rx function leads to a lack of eye development in a variety of species. Here we show that Rx function is also necessary during retinal regeneration. We performed a thorough characterization of retinal regeneration after partial retinal resection in pre-metamorphic X. laevis. We show that after injury the wound is repopulated with retinal progenitor cells (RPCs) that express Rx and other RPC marker genes. We used an shRNA-based approach to specifically silence Rx expression in vivo in tadpoles. We found that loss of Rx function results in impaired retinal regeneration, including defects in the cells that repopulate the wound and the RPE at the wound site. We show that the regeneration defects can be rescued by provision of exogenous Rx. These results demonstrate for the first time that Rx, in addition to being essential during retinal development, also functions during retinal regeneration. PMID:21334323

  3. Comparison of central nervous system prophylaxis with cranial radiation and intrathecal methotrexate versus intrathecal methotrexate alone in acute lymphoblastic leukemia

    SciTech Connect

    Muriel, F.S.; Svarch, E.; Pavlovsky, S.; Eppinger-Helft, M.; Braier, J.; Vergara, B.; Garay, G.; Kvicala, R.; Divito, J.M.; Failace, R.

    1983-08-01

    In acute lymphoblastic leukemia, central nervous system prophylaxis with irradiation plus intrathecal methotrexate (i.t. MTX) reduces the incidence of CNS relapse to 7%-15%. However, increased evidence of CNS delayed toxicity was recognized mainly in children as CT scan abnormalities and neuropsychologic alterations. Two questions were analyzed: (1) Will further doses of i.t. methotraxate and dexamethasone (i.t. MTX-DMT) decrease the incidence of CNS relapse. (2) Is i.t. MTX-DMT given during induction and maintenance as effective as cranium irradiation plus i.t. MTX-DMT. Incidence of primary CNS relapse in i.t. MTX-DMT-treated patients with a WBC count < 50,000 and in the untreated group was 11%. In patients with a WBC count > 50,000, it was 16% in the treated group and 19% in the control group. These patients were compared with patients which had received 3 doses of i.t. MTX-DMT alone during induction, 3 doses weekly during the first month of remission, and quarterly thereafter. The incidence of leukemia at 60 mo in patients with a WBC count < 50,000 was 20% in the irradiated group and 32% in the group with i.t. MTX-DMT alone. The relapse-free survival at 60 mo was 26% and 41%, respectively, (p < 0.0005). The incidence in patients with a WBC count > 50,000 at 48 mo was 28% and 42% in the irradiated and nonirradiated group respectively. Complete remission remained at 15% and 16% respectively of patients disease-free at 48 mo. We conclude that (A) after cranial irradiation plus i.t. MTX-DMT X 5, the use of additional doses of i.t. MTX-DMT is not of further benefit in preventing CNS relapse; (B) use of i.t. MTX-DMT alone compares with cranial irradiation plus i.t. MTX-DMT in incidence of CNS relapse; and (C) relapse-free survival and survival in patients with a WBC count < 50.000 were significantly longer in those without cranial irradiation.

  4. Retinal Detachment: Torn or Detached Retina Diagnosis

    MedlinePlus

    ... Eye Health / Eye Health A-Z Detached or Torn Retina Sections Retinal Detachment: What Is a Torn ... Retina Treatment Retinal Detachment Vision Simulator Retinal Detachment: Torn or Detached Retina Diagnosis Written by: Kierstan Boyd ...

  5. Retinal Detachment: Torn or Detached Retina Symptoms

    MedlinePlus

    ... Eye Health / Eye Health A-Z Detached or Torn Retina Sections Retinal Detachment: What Is a Torn ... Retina Treatment Retinal Detachment Vision Simulator Retinal Detachment: Torn or Detached Retina Symptoms Written by: Kierstan Boyd ...

  6. Small Animal Retinal Imaging

    NASA Astrophysics Data System (ADS)

    Choi, WooJhon; Drexler, Wolfgang; Fujimoto, James G.

    Developing and validating new techniques and methods for small animal imaging is an important research area because there are many small animal models of retinal diseases such as diabetic retinopathy, age-related macular degeneration, and glaucoma [1-6]. Because the retina is a multilayered structure with distinct abnormalities occurring in different intraretinal layers at different stages of disease progression, there is a need for imaging techniques that enable visualization of these layers individually at different time points. Although postmortem histology and ultrastructural analysis can be performed for investigating microscopic changes in the retina in small animal models, this requires sacrificing animals, which makes repeated assessment of the same animal at different time points impossible and increases the number of animals required. Furthermore, some retinal processes such as neurovascular coupling cannot be fully characterized postmortem.

  7. Molecular pathogenesis of retinal and choroidal vascular diseases.

    PubMed

    Campochiaro, Peter A

    2015-11-01

    There are two major types of ocular neovascularization that affect the retina, retinal neovascularization (NV) and subretinal or choroidal NV. Retinal NV occurs in a group of diseases referred to as ischemic retinopathies in which damage to retinal vessels results in retinal ischemia. Most prevalent of these are diabetic retinopathy and retinal vein occlusions. Subretinal and choroidal NV occur in diseases of the outer retina and Bruch's membrane, the most prevalent of which is age-related macular degeneration. Numerous studies in mouse models have helped to elucidate the molecular pathogenesis underlying retinal, subretinal, and choroidal NV. There is considerable overlap because the precipitating event in each is stabilization of hypoxia inducible factor-1 (HIF-1) which leads to upregulation of several hypoxia-regulated gene products, including vascular endothelial growth factor (VEGF), angiopoietin 2, vascular endothelial-protein tyrosine phosphatase (VE-PTP), and several others. Stimulation of VEGF signaling and suppression of Tie2 by angiopoietin 2 and VE-PTP are critical for sprouting of retinal, subretinal, and choroidal NV, with perturbation of Bruch's membrane also needed for the latter. Additional HIF-1-regulated gene products cause further stimulation of the NV. It is difficult to model macular edema in animals and therefore proof-of-concept clinical trials were done and demonstrated that VEGF plays a central role and that suppression of Tie2 is also important. Neutralization of VEGF is currently the first line therapy for all of the above disease processes, but new treatments directed at some of the other molecular targets, particularly stabilization of Tie2, are likely to provide additional benefit for subretinal/choroidal NV and macular edema. In addition, the chronicity of these diseases as well as the implication of VEGF as a cause of retinal nonperfusion and progression of background diabetic retinopathy make sustained delivery approaches for VEGF

  8. 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

  9. The peripheral retinal 'map'.

    PubMed Central

    Williams, D. H.

    1975-01-01

    The condition of the periphery of the retinal field of the human eye is of considerable significance, it is suggested, to those participating in various sporting activities. Its boundaries shrink and expand depending upon the physiological conditions imposed both upon the eye and upon the organism as a whole. Consequently its message to the brain may be impaired under stress with resulting danger owing to delayed response. Images Fig. 3 Fig. 4 Fig. 5 PMID:1148574

  10. Inherited Retinal Degenerative Disease Registry

    ClinicalTrials.gov

    2016-03-21

    Eye Diseases Hereditary; Retinal Disease; Achromatopsia; Bardet-Biedl Syndrome; Bassen-Kornzweig Syndrome; Batten Disease; Best Disease; Choroidal Dystrophy; Choroideremia; Cone Dystrophy; Cone-Rod Dystrophy; Congenital Stationary Night Blindness; Enhanced S-Cone Syndrome; Fundus Albipunctatus; Goldmann-Favre Syndrome; Gyrate Atrophy; Juvenile Macular Degeneration; Kearns-Sayre Syndrome; Leber Congenital Amaurosis; Refsum Syndrome; Retinitis Pigmentosa; Retinitis Punctata Albescens; Retinoschisis; Rod-Cone Dystrophy; Rod Dystrophy; Rod Monochromacy; Stargardt Disease; Usher Syndrome

  11. Glutamatergic Retinal Waves

    PubMed Central

    Kerschensteiner, Daniel

    2016-01-01

    Spontaneous activity patterns propagate through many parts of the developing nervous system and shape the wiring of emerging circuits. Prior to vision, waves of activity originating in the retina propagate through the lateral geniculate nucleus (LGN) of the thalamus to primary visual cortex (V1). Retinal waves have been shown to instruct the wiring of ganglion cell axons in LGN and of thalamocortical axons in V1 via correlation-based plasticity rules. Across species, retinal waves mature in three stereotypic stages (I–III), in which distinct circuit mechanisms give rise to unique activity patterns that serve specific functions in visual system refinement. Here, I review insights into the patterns, mechanisms, and functions of stage III retinal waves, which rely on glutamatergic signaling. As glutamatergic waves spread across the retina, neighboring ganglion cells with opposite light responses (ON vs. OFF) are activated sequentially. Recent studies identified lateral excitatory networks in the inner retina that generate and propagate glutamatergic waves, and vertical inhibitory networks that desynchronize the activity of ON and OFF cells in the wavefront. Stage III wave activity patterns may help segregate axons of ON and OFF ganglion cells in the LGN, and could contribute to the emergence of orientation selectivity in V1. PMID:27242446

  12. Mitochondrial dysfunction in retinal diseases.

    PubMed

    Barot, Megha; Gokulgandhi, Mitan R; Mitra, Ashim K

    2011-12-01

    The mitochondrion is a vital intracellular organelle for retinal cell function and survival. There is growing confirmation to support an association between mitochondrial dysfunction and a number of retinal degenerations. Investigations have also unveiled mitochondrial genomic instability as one of the contributing factors for age-related retinal pathophysiology. This review highlights the role of mitochondrial dysfunction originating from oxidative stress in the etiology of retinal diseases including diabetic retinopathy, glaucoma and age-related macular degeneration (AMD). Moreover, mitochondrial DNA (mtDNA) damage associated with AMD due to susceptibility of mtDNA to oxidative damage and failure of mtDNA repair pathways is also highlighted in this review. The susceptibility of neural retina and retinal pigment epithelium (RPE) mitochondria to oxidative damage with ageing appears to be a major factor in retinal degeneration. It thus appears that the mitochondrion is a weak link in the antioxidant defenses of retinal cells. In addition, failure of mtDNA repair pathways can also specifically contribute towards pathogenesis of AMD. This review will further summarize the prospective role of mitochondria targeting therapeutic agents for the treatment of retinal disease. Mitochondria based drug targeting to diminish oxidative stress or promote repair of mtDNA damage may offer potential alternatives for the treatment of various retinal degenerative diseases.

  13. Influence of central neurotransmitters on heart rate variability in outbred rats at rest and during acute stress: nature of very-low-wave spectrum component revisited.

    PubMed

    Kurjanova, E V; Teplyj, D L

    2010-07-01

    We studied the effect of blockade of neurotransmitter monoamine reuptake and inhibition of catecholamine synthesis on heart rate variability in outbred albino rats at rest and during acute stress. Amitriptyline increased, while α-methyltyrosine reduced the power of VLF waves in heart rate variability spectrum. The effect of amitriptyline manifested at rest and was most striking under stressful conditions, while the effect of α-methyltyrosine was observed only under conditions of acute stress. This suggests that VLF-band waves in the heart rate variability spectrum have catecholaminergic nature and are determined by activity of the central monoaminergic systems; the role of peripheral adrenergic influences mediated by humoral and nervous regulation in the formation of these waves cannot also be excluded.

  14. Glaucoma-induced degeneration of retinal ganglion cells prevented by hypoxic preconditioning: a model of glaucoma tolerance.

    PubMed

    Zhu, Yanli; Zhang, Lihong; Schmidt, Jimena F; Gidday, Jeffrey M

    2012-01-01

    Like all cells, neurons adapt to stress by transient alterations in phenotype, an epigenetic response that forms the basis for preconditioning against acute ischemic injury in the central nervous system. We recently showed that a modified repetitive hypoxic preconditioning (RHP) regimen significantly extends the window of ischemic tolerance to acute retinal ischemic injury from days to months. The present study was undertaken to determine if this uniquely protracted neuroprotective phenotype would also confer resistance to glaucomatous neurodegeneration. Retinal ganglion cell death at somatic and axonal levels was assessed after both 3 and 10 wks of sustained intraocular hypertension in an adult mouse model of inducible, open-angle glaucoma, with or without RHP before intraocular pressure elevation. Loss of brn3-positive ganglion cell soma after 3 wks of experimental glaucoma, along with increases in several apoptotic endpoints, were all significantly and robustly attenuated in mice subjected to RHP. Soma protection by RHP was also confirmed after 10 wks of intraocular hypertension by brn3 and SMI32 immunostaining. In addition, quantification of axon density in the postlaminar optic nerve documented robust preservation in RHP-treated mice, and neurofilament immunostaining also revealed preconditioning-induced improvements in axon integrity/survival in both retina and optic nerve after 10 wks of experimental glaucoma. This uniquely protracted period of phenotypic change, established in retinal ganglion cells by the activation of latent antiapoptotic, prosurvival mechanisms at both somatic and axonal levels, reflects a novel form of inducible neuronal plasticity that may provide innovative therapeutic targets for preventing and treating glaucoma and other neurodegenerative diseases. PMID:22396016

  15. The effect of acute and chronic restraint on the central expression of prepro-neuropeptide Y mRNA in normotensive and hypertensive rats.

    PubMed

    Sweerts, B W; Jarrott, B; Lawrence, A J

    2001-07-01

    Neuropeptide Y (NPY), one of the most abundant neuropeptides found in the central nervous system (CNS), has been implicated in the regulation of many autonomic functions, including cardiovascular control and the central stress response. The present study represents a detailed investigation of the effects of acute and chronic restraint stress on the expression of the mRNA encoding the NPY precursor, prepro-NPY, in the CNS of normotensive Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR) using in situ hybridization histochemistry. Basal (unstressed) levels of prepro-NPY mRNA expression were found to be significantly increased in the hypothalamic arcuate nucleus of SHR compared to WKY rats, with similar levels of prepro-NPY mRNA expression found in the remaining central nuclei. Following exposure to both acute and chronic restraint, significant changes in prepro-NPY mRNA expression were found in a variety of central regions in both strains, including the arcuate nucleus and hippocampus (both strains), medial amygdala and cortex (WKY only), and dentate gyrus, nucleus of the solitary tract and ventrolateral medulla (SHR only). A comparison of the temporal response to restraint revealed that significant differences between strains existed in regions such as the arcuate nucleus, hippocampus and dentate gyrus, providing further evidence that hypertensive rats apparently have an impaired neural stress response. The present study demonstrates that exposure to restraint results in significant changes in prepro-NPY mRNA expression in specific nuclei of both WKY and SHR that are components of not only the central circuitry regulating the stress response, but also the neural network modulating autonomic function.

  16. Intraocular retinal prosthesis.

    PubMed Central

    Humayun, M S

    2001-01-01

    PURPOSE: An electronic implant that can bypass the damaged photoreceptors and electrically stimulate the remaining retinal neurons to restore useful vision has been proposed. A number of key questions remain to make this approach feasible. The goal of this thesis is to address the following 2 specific null hypotheses: (1) Stimulus parameters make no difference in the electrically elicited retinal responses. (2) Just as we have millions of photoreceptors, so it will take a device that can generate millions of pixels/light points to create useful vision. METHODS: For electrophysiologic experiments, 2 different setups were used. In the first setup, charge-balanced pulses were delivered to the retinal surface via electrodes inserted through an open sky approach in normal or blind retinal degenerate (rd) mice. In the second setup, the rabbit retina was removed under red light conditions from an enucleated eye and then maintained in a chamber while being superfused with oxygenated, heated Ames media. In both setups, stimulating electrodes and recording electrodes were positioned on the retinal surface to evaluate the effect of varying stimulation parameters on the orthodromic retinal responses (i.e., recording electrode placed between stimulating electrodes and optic nerve head). For psychophysical experiments, visual images were divided into pixels of light that could be projected in a pattern on the retina in up to 8 sighted volunteers. Subjects were asked to perform various tasks ranging from reading and face recognition to various activities of daily living. RESULTS: Electrophysiologic experiments: In a normal mouse, a single cycle of a 1-kHz sine wave was significantly more efficient than a 1-kHz square wave (P < .05), but no such difference was noted in either of the 8- or 16-week-old rd mouse groups (8-week-old, P = .426; 16-week-old, P = .078). Charge threshold was significantly higher in 16-week-old rd mouse versus both 8-week-old rd and normal mouse for every

  17. Nonketotic hyperosmolar syndrome as an acute complication of type 1 diabetes onset in a 20-month-old boy with congenital central nervous system defect.

    PubMed

    Chumiecki, Miron; Minkina-Pedras, Mariola; Chobot, Agata; Jarosz-Chobot, Przemysława

    2012-01-01

    Hyperglycemic hyperosmolar syndrome (HHS) is one of the most severe acute complications of type 2 diabetes, but may also be developed in type 1 diabetes. Similar to ketoacidosis,HHS still remains one of the major causes of morbidity and mortality in patients with diabetes,despite a significant progress in understanding its pathogenesis and greater consensus on HHS diagnosis and treatment. It is mainly observed in elderly patients with type 2 diabetes. However,it may also occur in children,especially in infants and those with concomitant central nervous system (CNS) defects or suffering from severe infections associated with dehydration. The authors report a case of HHS in a 20-month-old child with central nervous system abnormality. Symptoms observed in our patient are characteristic for HHS. It must be emphasized that HHS may accompany diabetes onset also in children.

  18. Retinal Imaging and Image Analysis

    PubMed Central

    Abràmoff, Michael D.; Garvin, Mona K.; Sonka, Milan

    2011-01-01

    Many important eye diseases as well as systemic diseases manifest themselves in the retina. While a number of other anatomical structures contribute to the process of vision, this review focuses on retinal imaging and image analysis. Following a brief overview of the most prevalent causes of blindness in the industrialized world that includes age-related macular degeneration, diabetic retinopathy, and glaucoma, the review is devoted to retinal imaging and image analysis methods and their clinical implications. Methods for 2-D fundus imaging and techniques for 3-D optical coherence tomography (OCT) imaging are reviewed. Special attention is given to quantitative techniques for analysis of fundus photographs with a focus on clinically relevant assessment of retinal vasculature, identification of retinal lesions, assessment of optic nerve head (ONH) shape, building retinal atlases, and to automated methods for population screening for retinal diseases. A separate section is devoted to 3-D analysis of OCT images, describing methods for segmentation and analysis of retinal layers, retinal vasculature, and 2-D/3-D detection of symptomatic exudate-associated derangements, as well as to OCT-based analysis of ONH morphology and shape. Throughout the paper, aspects of image acquisition, image analysis, and clinical relevance are treated together considering their mutually interlinked relationships. PMID:21743764

  19. Perceptual Fading without Retinal Adaptation

    ERIC Educational Resources Information Center

    Hsieh, Po-Jang; Colas, Jaron T.

    2012-01-01

    A retinally stabilized object readily undergoes perceptual fading and disappears from consciousness. This startling phenomenon is commonly believed to arise from local bottom-up sensory adaptation to edge information that occurs early in the visual pathway, such as in the lateral geniculate nucleus of the thalamus or retinal ganglion cells. Here…

  20. High resolution optoelectronic retinal prosthesis

    NASA Astrophysics Data System (ADS)

    Loudin, Jim; Dinyari, Rostam; Huie, Phil; Butterwick, Alex; Peumans, Peter; Palanker, Daniel

    2009-02-01

    Electronic retinal prostheses seek to restore sight in patients with retinal degeneration by delivering pulsed electric currents to retinal neurons via an array of microelectrodes. Most implants use inductive or optical transmission of information and power to an intraocular receiver, with decoded signals subsequently distributed to retinal electrodes through an intraocular cable. Surgical complexity could be minimized by an "integrated" prosthesis, in which both power and data are delivered directly to the stimulating array without any discrete components or cables. We present here an integrated retinal prosthesis system based on a photodiode array implant. Video frames are processed and imaged onto the retinal implant by a video goggle projection system operating at near-infrared wavelengths (~ 900 nm). Photodiodes convert light into pulsed electric current, with charge injection maximized by specially optimized series photodiode circuits. Prostheses of three different pixel densities (16 pix/mm2, 64 pix/mm2, and 256 pix/mm2) have been designed, simulated, and prototyped. Retinal tissue response to subretinal implants made of various materials has been investigated in RCS rats. The resulting prosthesis can provide sufficient charge injection for high resolution retinal stimulation without the need for implantation of any bulky discrete elements such as coils or tethers. In addition, since every pixel functions independently, pixel arrays may be placed separately in the subretinal space, providing visual stimulation to a larger field of view.

  1. Retinal connectivity and primate vision

    PubMed Central

    Lee, Barry B.; Martin, Paul R.; Grünert, Ulrike

    2012-01-01

    The general principles of retinal organization are now well known. It may seem surprising that retinal organization in the primate, which has a complex visual behavioral repertoire, appears relatively simple. In this review, we primarily consider retinal structure and function in primate species. Photoreceptor distribution and connectivity are considered as are connectivity in the outer and inner retina. One key issue is the specificity of retinal connections; we suggest that the retina shows connectional specificity but this is seldom complete, and we consider here the functional consequences of imprecise wiring. Finally, we consider how retinal systems can be linked to psychophysical descriptions of different channels, chromatic and luminance, which are proposed to exist in the primate visual system. PMID:20826226

  2. Acute Toluene Exposure Alters Expression of Genes in the Central Nervous System Associated With Synaptic Structure and Function

    EPA Science Inventory

    Toluene is a volatile organic compound (VOC) and a ubiquitous air pollutant of interest to EPA regulatory programs. Whereas its acute functional effects are well described, several modes of action in the CNS have been proposed. Therefore, we sought to identify potential pathways ...

  3. Amyloidosis in Retinal Neurodegenerative Diseases.

    PubMed

    Masuzzo, Ambra; Dinet, Virginie; Cavanagh, Chelsea; Mascarelli, Frederic; Krantic, Slavica

    2016-01-01

    As a part of the central nervous system, the retina may reflect both physiological processes and abnormalities related to pathologies that affect the brain. Amyloidosis due to the accumulation of amyloid-beta (Aβ) was initially regarded as a specific and exclusive characteristic of neurodegenerative alterations seen in the brain of Alzheimer's disease (AD) patients. More recently, it was discovered that amyloidosis-related alterations, similar to those seen in the brain of Alzheimer's patients, also occur in the retina. Remarkably, these alterations were identified not only in primary retinal pathologies, such as age-related macular degeneration (AMD) and glaucoma, but also in the retinas of Alzheimer's patients. In this review, we first briefly discuss the biogenesis of Aβ, a peptide involved in amyloidosis. We then discuss some pathological aspects (synaptic dysfunction, mitochondrial failure, glial activation, and vascular abnormalities) related to the neurotoxic effects of Aβ. We finally highlight common features shared by AD, AMD, and glaucoma in the context of Aβ amyloidosis and further discuss why the retina, due to the transparency of the eye, can be considered as a "window" to the brain. PMID:27551275

  4. Amyloidosis in Retinal Neurodegenerative Diseases

    PubMed Central

    Masuzzo, Ambra; Dinet, Virginie; Cavanagh, Chelsea; Mascarelli, Frederic; Krantic, Slavica

    2016-01-01

    As a part of the central nervous system, the retina may reflect both physiological processes and abnormalities related to pathologies that affect the brain. Amyloidosis due to the accumulation of amyloid-beta (Aβ) was initially regarded as a specific and exclusive characteristic of neurodegenerative alterations seen in the brain of Alzheimer’s disease (AD) patients. More recently, it was discovered that amyloidosis-related alterations, similar to those seen in the brain of Alzheimer’s patients, also occur in the retina. Remarkably, these alterations were identified not only in primary retinal pathologies, such as age-related macular degeneration (AMD) and glaucoma, but also in the retinas of Alzheimer’s patients. In this review, we first briefly discuss the biogenesis of Aβ, a peptide involved in amyloidosis. We then discuss some pathological aspects (synaptic dysfunction, mitochondrial failure, glial activation, and vascular abnormalities) related to the neurotoxic effects of Aβ. We finally highlight common features shared by AD, AMD, and glaucoma in the context of Aβ amyloidosis and further discuss why the retina, due to the transparency of the eye, can be considered as a “window” to the brain. PMID:27551275

  5. Selective inner retinal layer involvement in early syphilitic retinitis as evidenced by spectral domain OCT

    PubMed Central

    Klemencic, Stephanie A.; Newman, Tricia L.; Messner, Leonard V.

    2011-01-01

    Retinitis as a feature of syphilitic uveitis in immunocompromised individuals is a common finding. We present spectral domain OCT images of early syphilitic retinitis pre and post treatment with penicillin. This case suggests that the inner retinal layers may be selectively involved with early syphilitic retinitis. Early treatment is important to avoid outer layer retinal involvement and to decrease ocular morbidity.

  6. Pregnancy-associated retinal diseases and their management.

    PubMed

    Errera, Marie-Hélène; Kohly, Radha P; da Cruz, Lyndon

    2013-01-01

    Pregnancy-associated retinal diseases are conditions that may occur uniquely in pregnancy or, more commonly, general conditions that may worsen or alter during pregnancy as a result of hematologic, hormonal, metabolic, cardiovascular, and immunologic changes. Diabetic retinopathy (DR) is by far the most common retinal condition that is altered by pregnancy. However, there are currently no widely accepted, precise clinical guidelines regarding its management during pregnancy. At present it is not possible to predict who will regress and who will progress without treatment. Some of the variation in progression of DR in pregnancy may be a result of well-known risk factors such as hypertension or inadequate glycemic control prior to pregnancy. Other pregnancy-associated retinal diseases are relatively uncommon, and their treatments are poorly characterized. Pre-existing conditions include the white dot syndromes, such as punctuate inner choroidopathy and ocular histoplasmosis syndrome, as well as chorioretinal neovascularization from many other etiologies. Retinal and chorioretinal disorders that can arise during pregnancy include central serous chorioretinopathy and occlusive vasculopathy such as retinal artery occlusion (Purtschers-like retinopathy) and retinal vein occlusion. There remains a small group that appear to be unique to pregnancy, with pre-eclampsia- and eclampsia-associated retinopathy, disseminated intravascular coagulopathy, or amniotic fluid embolism being the best described. In angiogenic retinal diseases outside of pregnancy, the use of anti-vascular endothelial growth factor (anti-VEGF agents) has proven helpful. There are no safety data about the use of anti-VEGF agents during pregnancy, and conventionally the proposed interventions have been laser photocoagulation and systemic or intravitreal injections of steroids. Most of the literature on the treatment of pregnancy associated-chorioretinal neovascularization is anecdotal.

  7. The Role of the Endothelin System in the Vascular Dysregulation Involved in Retinitis Pigmentosa

    PubMed Central

    Sorrentino, Francesco Saverio; Bonifazzi, Claudio; Perri, Paolo

    2015-01-01

    Retinitis pigmentosa is a clinical and genetic group of inherited retinal disorders characterized by alterations of photoreceptors and retinal pigment epithelium leading to a progressive concentric visual field restriction, which may bring about severe central vision impairment. Haemodynamic studies in patients with retinitis pigmentosa have demonstrated ocular blood flow abnormalities both in retina-choroidal and in retroocular vascular system. Moreover, several investigations have studied the augmentation of endothelin-1 plasma levels systemically in the body and locally in the eye. This might account for vasoconstriction and ischemia, typical in vascular dysregulation syndrome, which can be considered an important factor of reduction of the ocular blood flow in subjects affected by retinitis pigmentosa. PMID:26613048

  8. White Matter Consequences of Retinal Receptor and Ganglion Cell Damage

    PubMed Central

    Ogawa, Shumpei; Takemura, Hiromasa; Horiguchi, Hiroshi; Terao, Masahiko; Haji, Tomoki; Pestilli, Franco; Yeatman, Jason D.; Tsuneoka, Hiroshi; Wandell, Brian A.; Masuda, Yoichiro

    2014-01-01

    Purpose. Patients with Leber hereditary optic neuropathy (LHON) and cone-rod dystrophy (CRD) have central vision loss; but CRD damages the retinal photoreceptor layer, and LHON damages the retinal ganglion cell (RGC) layer. Using diffusion MRI, we measured how these two types of retinal damage affect the optic tract (ganglion cell axons) and optic radiation (geniculo-striate axons). Methods. Adult onset CRD (n = 5), LHON (n = 6), and healthy controls (n = 14) participated in the study. We used probabilistic fiber tractography to identify the optic tract and the optic radiation. We compared axial and radial diffusivity at many positions along the optic tract and the optic radiation. Results. In both types of patients, diffusion measures within the optic tract and the optic radiation differ from controls. The optic tract change is principally a decrease in axial diffusivity; the optic radiation change is principally an increase in radial diffusivity. Conclusions. Both photoreceptor layer (CRD) and retinal ganglion cell (LHON) retinal disease causes substantial change in the visual white matter. These changes can be measured using diffusion MRI. The diffusion changes measured in the optic tract and the optic radiation differ, suggesting that they are caused by different biological mechanisms. PMID:25257055

  9. Blood Pressure Modifies Retinal Susceptibility to Intraocular Pressure Elevation

    PubMed Central

    He, Zheng; Nguyen, Christine T. O.; Armitage, James A.; Vingrys, Algis J.; Bui, Bang V.

    2012-01-01

    Primary open angle glaucoma affects more than 67 million people. Elevated intraocular pressure (IOP) is a risk factor for glaucoma and may reduce nutrient availability by decreasing ocular perfusion pressure (OPP). An interaction between arterial blood pressure and IOP determines OPP; but the exact contribution that these factors have for retinal function is not fully understood. Here we sought to determine how acute modifications of arterial pressure will affect the susceptibility of neuronal function and blood flow to IOP challenge. Anaesthetized (ketamine:xylazine) Long-Evan rats with low (∼60 mmHg, sodium nitroprusside infusion), moderate (∼100 mmHg, saline), or high levels (∼160 mmHg, angiotensin II) of mean arterial pressure (MAP, n = 5–10 per group) were subjected to IOP challenge (10–120 mmHg, 5 mmHg steps every 3 minutes). Electroretinograms were measured at each IOP step to assess bipolar cell (b-wave) and inner retinal function (scotopic threshold response or STR). Ocular blood flow was measured using laser-Doppler flowmetry in groups with similar MAP level and the same IOP challenge protocol. Both b-wave and STR amplitudes decreased with IOP elevation. Retinal function was less susceptible to IOP challenge when MAP was high, whereas the converse was true for low MAP. Consistent with the effects on retinal function, higher IOP was needed to attenuated ocular blood flow in animals with higher MAP. The susceptibility of retinal function to IOP challenge can be ameliorated by acute high BP, and exacerbated by low BP. This is partially mediated by modifications in ocular blood flow. PMID:22359566

  10. Late Postoperative Evaluation of Retinal and Choroidal Thickness and Retinal Vessel Caliber after Surgical Repair of Corneal Perforation

    PubMed Central

    Pekel, Gökhan; Acer, Semra; Cesur, Nihal; Yağcı, Ramazan; Nevin Çetin, Ebru

    2015-01-01

    Objectives: To examine the late period retinal and choroidal alterations in the posterior pole of eyes that underwent primary suturing due to traumatic corneal perforation. Materials and Methods: This cross-sectional case series included 21 eyes of 21 patients. The fellow eyes served as the control group. Macular thickness, peripapillary retinal nerve fiber layer (RNFL) thickness, choroidal thickness, and retinal vessel caliber measurements were performed by spectral-domain optical coherence tomography (SD-OCT). Results: The mean RNFL thickness was 102.1±10.9 µm in the perforated eyes and 99.5±8.5 µm in the fellow eyes (p=0.29). The mean central macular thickness was 300.1±25.6 µm in the perforated eyes and 295.6±23.2 µm in the fellow eyes (p=0.62). The choroidal thickness and retinal vascular caliber measurements were also similar between the groups (p>0.05). Conclusion: Operated traumatic corneal perforations do not cause significant posterior pole retinal and choroidal SD-OCT thickness changes in the late postoperative period. PMID:27800241

  11. Acute Central Neuropeptide Y Administration Increases Food Intake but Does Not Affect Hepatic Very Low-Density Lipoprotein (Vldl) Production in Mice

    PubMed Central

    Havekes, Louis M.; Romijn, Johannes A.; Rensen, Patrick C. N.

    2013-01-01

    Objective Central neuropeptide Y (NPY) administration stimulates food intake in rodents. In addition, acute modulation of central NPY signaling increases hepatic production of very low-density lipoprotein (VLDL)-triglyceride (TG) in rats. As hypertriglyceridemia is an important risk factor for atherosclerosis, for which well-established mouse models are available, we set out to validate the effect of NPY on hepatic VLDL-TG production in mice, to ultimately investigate whether NPY, by increasing VLDL production, contributes to the development of atherosclerosis. Research Design and Methods Male C57Bl/6J mice received an intracerebroventricular (i.c.v.) cannula into the lateral (LV) or third (3V) ventricle of the brain. One week later, after a 4 h fast, the animals received an intravenous (i.v.) injection of Tran35S (100 µCi) followed by tyloxapol (500 mg/kg body weight; BW), enabling the study of hepatic VLDL-apoB and VLDL-TG production, respectively. Immediately after the i.v. injection of tyloxapol, the animals received either an i.c.v. injection of NPY (0.2 mg/kg BW in artificial cerebrospinal fluid; aCSF), synthetic Y1 receptor antagonist GR231118 (0.5 mg/kg BW in aCSF) or vehicle (aCSF), or an i.v. injection of PYY3–36 (0.5 mg/kg BW in PBS) or vehicle (PBS). Results Administration of NPY into both the LV and 3V increased food intake within one hour after injection (+164%, p<0.001 and +367%, p<0.001, respectively). NPY administration neither in the LV nor in the 3V affected hepatic VLDL-TG or VLDL-apoB production. Likewise, antagonizing central NPY signaling by either PYY3–36 or GR231118 administration did not affect hepatic VLDL production. Conclusion In mice, as opposed to rats, acute central administration of NPY increases food intake without affecting hepatic VLDL production. These results are of great significance when extrapolating findings on the central regulation of hepatic VLDL production between species. PMID:23460782

  12. Multimodal retinal imaging of diabetic macular edema: toward new paradigms of pathophysiology.

    PubMed

    Midena, Edoardo; Bini, Silvia

    2016-09-01

    The pathophysiology of diabetic macular edema (DME) is multifactorial and partly still unknown. An increasing body of evidence suggests that neurodegeneration and retinal glial cells activation occur even before the earliest clinical manifestation of diabetic retinal vasculopathy. Nowadays, new non-invasive techniques are available to assess and characterize DME, not only in a quantitative perspective, but also making it possible to understand and quantify the pathogenic processes sustaining fluid accumulation. Optical coherence tomography (OCT) allows documenting not only parameters such as macular volume, central and sectorial retinal thickness, fluid localization, and integrity of retinal layers, but also new still poorly investigated reflectivity aspects. Hyperreflective intraretinal spots (HRS) have been detected on OCT scans through the retinal layers, with a presumptive migration pattern towards the external layers during the occurrence of diabetic retinopathy and DME. These HRS have been hypothesised to represent an in-vivo marker of microglial activation. Autofluorescence of the fundus (FAF) also offers a non-invasive imaging technique of DME. The area of increased FAF correlates with the presence of intraretinal fluid and probably retinal glial activation. Microperimetry allows the measurement of retinal sensitivity by testing specific selected retinal areas. Some studies have shown that increased macular FAF in DME correlates better with visual function assessed with microperimetry than with visual acuity, showing that new imaging and functional techniques may help to elucidate DME pathogenesis and to target therapeutical strategies. PMID:27154296

  13. Divergent neuronal circuitries underlying acute orexigenic effects of peripheral or central ghrelin: critical role of brain accessibility.

    PubMed

    Cabral, A; Valdivia, S; Fernandez, G; Reynaldo, M; Perello, M

    2014-08-01

    Ghrelin is an octanoylated peptide hormone that potently and rapidly increases food intake. The orexigenic action of ghrelin involves the hypothalamic arcuate nucleus (ARC), which is accessible to plasma ghrelin and expresses high levels of the ghrelin receptor. Local administration of ghrelin in a variety of other brain nuclei also increases food intake. It is currently unclear, however, whether these non-ARC ghrelin brain targets are impacted by physiological increases of plasma ghrelin. Thus, the present study aimed to clarify which ghrelin brain targets participate in the short-term orexigenic actions of ghrelin. First, c-Fos induction into mouse brains centrally or peripherally treated with ghrelin was analysed. It was confirmed that peripherally administered ghrelin dose-dependently increases food intake and mainly activates c-Fos in ARC neurones. By contrast, centrally administered ghrelin activates c-Fos in a larger number of brain nuclei. To determine which nuclei are directly accessible to ghrelin, mice were centrally or peripherally injected with a fluorescent ghrelin tracer. It was found that peripherally injected tracer mainly accesses the ARC, whereas centrally injected tracer reaches most brain areas known to express ghrelin receptors. Subsequently, the effects of ghrelin were tested in ARC-ablated mice and it was found that these mice failed to increase food intake in response to peripherally administered ghrelin but fully responded to centrally administered ghrelin. ARC-ablated mice showed patterns of ghrelin-induced c-Fos expression similar to those seen in control mice with the exception of the ARC, where no c-Fos was found. Thus, peripheral ghrelin mainly accesses the ARC, which is required for the orexigenic effects of the hormone. Central ghrelin accesses a variety of nuclei, which can mediate the orexigenic effects of the hormone, even in the absence of an intact ARC.

  14. Flexible retinal electrode array

    DOEpatents

    Okandan, Murat; Wessendorf, Kurt O.; Christenson, Todd R.

    2006-10-24

    An electrode array which has applications for neural stimulation and sensing. The electrode array can include a large number of electrodes each of which is flexibly attached to a common substrate using a plurality of springs to allow the electrodes to move independently. The electrode array can be formed from a combination of bulk and surface micromachining, with electrode tips that can include an electroplated metal (e.g. platinum, iridium, gold or titanium) or a metal oxide (e.g. iridium oxide) for biocompatibility. The electrode array can be used to form a part of a neural prosthesis, and is particularly well adapted for use in an implantable retinal prosthesis where the electrodes can be tailored to provide a uniform gentle contact pressure with optional sensing of this contact pressure at one or more of the electrodes.

  15. Acute inhibition of central c-Jun N-terminal kinase restores hypothalamic insulin signalling and alleviates glucose intolerance in diabetic mice.

    PubMed

    Benzler, J; Ganjam, G K; Legler, K; Stöhr, S; Krüger, M; Steger, J; Tups, A

    2013-05-01

    The hypothalamus has been identified as a main insulin target tissue for regulating normal body weight and glucose metabolism. Recent observations suggest that c-Jun-N-terminal kinase (JNK)-signalling plays a crucial role in the development of obesity and insulin resistance because neuronal JNK-1 ablation in the mouse prevented high-fat diet-induced obesity (DIO) and increased energy expenditure, as well as insulin sensitivity. In the present study, we investigated whether central JNK inhibition is associated with sensitisation of hypothalamic insulin signalling in mice fed a high-fat diet for 3 weeks and in leptin-deficient mice. We determined whether i.c.v. injection of a pharmacological JNK-inhibitor (SP600125) improved impaired glucose homeostasis. By immunohistochemistry, we first observed that JNK activity was increased in the arcuate nucleus (ARC) and the ventromedial hypothalamus (VMH) in both mouse models, relative to normoglycaemic controls. This suggests that up-regulation of JNK in these regions is associated with glucose intolerance and obesity, independent of leptin levels. Acute i.c.v. injection of SP600125 ameliorated glucose tolerance within 30 min in both leptin-deficient and DIO mice. Given the acute nature of i.c.v. injections, these effects cannot be attributed to changes in food intake or energy balance. In a hypothalamic cell line, and in the ARC and VMH of leptin-deficient mice, JNK inhibition by SP600125 consistently improved impaired insulin signalling. This was determined by a reduction of phospho-insulin receptor substrate-1 [IRS-1(Ser612)] protein in a hypothalamic cell line and a decline in the number of pIRS-1(Ser612) immunoreactive cells in the ARC and VMH. Serine 612 phosphorylation of IRS-1 is assumed to negatively regulate insulin signalling. In leptin-deficient mice, in both nuclei, central inhibition of JNK increased the number of cells immunoreactive for phospho-Akt (Ser473) and phospho-GSK-3β (Ser9), which are important

  16. Vitreal Ocygenation in Retinal Ischemia Reperfusion

    SciTech Connect

    Abdallab, Walid; AmeriMD, Hossein; Barron, Ernesto; ChaderPhD, Gerald; Greenbaum, Elias; Hinton, David E; Humayun, Mark S

    2011-01-01

    PURPOSE. To study the feasibility of anterior vitreal oxygenation for the treatment of acute retinal ischemia. METHODS. Twenty rabbits were randomized into an oxygenation group, a sham treatment group, and a no treatment group. Baseline electroretinography (ERG) and preretinal oxygen (PO2) measurements were obtained 3 to 5 days before surgery. Intraocular pressure was raised to 100 mm Hg for 90 minutes and then normalized. The oxygenation group underwent vitreal oxygenation for 30 minutes using intravitreal electrodes. The sham treatment group received inactive electrodes for 30 minutes while there was no intervention for the no treatment group. Preretinal PO2 in the posterior vitreous was measured 30 minutes after intervention or 30 minutes after reperfusion (no treatment group) and on postoperative days (d) 3, 6, 9, and 12. On d14, rabbits underwent ERG and were euthanatized.

  17. Intraocular retinal transplantation: a review.

    PubMed

    Hammer, R M; Yinon, U

    1991-01-01

    This review covers intraocular transplantation of retinal tissue. This has importance both for theoretical understanding of retinal and neural development and for possible future clinical application. Transplantation sites have ranged from the anterior chamber through the retina to the subretinal space. Transplanted tissue has ranged from whole retina to specific retinal layers or specific types of retinal cells. Both within-species and inter-species transplants have been performed, and donor age has ranged from embryonic to adult. The ability of transplanted tissue to be accepted and to differentiate in host eyes has been studied. The conditions under which successful transplants are obtained, host-graft interactions, and transplantation methodologies have been explored. Morphological, and to a small extent, also functional characteristics of the transplants have been studied. PMID:1747393

  18. A case of atypical progressive outer retinal necrosis after highly active antiretroviral therapy.

    PubMed

    Woo, Se Joon; Yu, Hyeong Gon; Chung, Hum

    2004-06-01

    This is a report of an atypical case of progressive outer retinal necrosis (PORN) and the effect of highly active antiretroviral therapy (HAART) on the clinical course of viral retinitis in an acquired immunodeficiency syndrome (AIDS) patient. A 22-year-old male patient infected with human immunodeficiency virus (HIV) presented with unilaterally reduced visual acuity and a dense cataract. After cataract extraction, retinal lesions involving the peripheral and macular areas were found with perivascular sparing and the mud-cracked, characteristic appearance of PORN. He was diagnosed as having PORN based on clinical features and was given combined antiviral treatment. With concurrent HAART, the retinal lesions regressed, with the regression being accelerated by further treatment with intravenous acyclovir and ganciclovir. This case suggests that HAART may change the clinical course of PORN in AIDS patients by improving host immunity. PORN should be included in the differential diagnosis of acute unilateral cataract in AIDS patients. PMID:15255240

  19. A case of atypical progressive outer retinal necrosis after highly active antiretroviral therapy.

    PubMed

    Woo, Se Joon; Yu, Hyeong Gon; Chung, Hum

    2004-06-01

    This is a report of an atypical case of progressive outer retinal necrosis (PORN) and the effect of highly active antiretroviral therapy (HAART) on the clinical course of viral retinitis in an acquired immunodeficiency syndrome (AIDS) patient. A 22-year-old male patient infected with human immunodeficiency virus (HIV) presented with unilaterally reduced visual acuity and a dense cataract. After cataract extraction, retinal lesions involving the peripheral and macular areas were found with perivascular sparing and the mud-cracked, characteristic appearance of PORN. He was diagnosed as having PORN based on clinical features and was given combined antiviral treatment. With concurrent HAART, the retinal lesions regressed, with the regression being accelerated by further treatment with intravenous acyclovir and ganciclovir. This case suggests that HAART may change the clinical course of PORN in AIDS patients by improving host immunity. PORN should be included in the differential diagnosis of acute unilateral cataract in AIDS patients.

  20. The mechanics of retinal detachment

    NASA Astrophysics Data System (ADS)

    Chou, Tom; Siegel, Michael

    2013-03-01

    We present a model of the mechanical and fluid forces associated with exudative retinal detachments where the retinal photoreceptor cells separate typically from the underlying retinal pigment epithelium (RPE). By computing the total fluid volume flow arising from transretinal, vascular, and retinal pigment epithelium (RPE) pump currents, we determine the conditions under which the subretinal fluid pressure exceeds the maximum yield stress holding the retina and RPE together, giving rise to an irreversible, extended retinal delamination. We also investigate localized, blister-like retinal detachments by balancing mechanical tension in the retina with both the retina-RPE adhesion energy and the hydraulic pressure jump across the retina. For detachments induced by traction forces, we find a critical radius beyond which the blister is unstable to growth. Growth of a detached blister can also be driven by inflamed tissue within which e.g., the hydraulic conductivities of the retina or choroid increase, the RPE pumps fail, or the adhesion properties change. We determine the parameter regimes in which the blister either becomes unstable to growth, remains stable and finite-sized, or shrinks, allowing possible healing. This work supported by the Army Research Office through grant 58386MA

  1. Retinal oxygen extraction in humans

    NASA Astrophysics Data System (ADS)

    Werkmeister, René M.; Schmidl, Doreen; Aschinger, Gerold; Doblhoff-Dier, Veronika; Palkovits, Stefan; Wirth, Magdalena; Garhöfer, Gerhard; Linsenmeier, Robert A.; Leitgeb, Rainer A.; Schmetterer, Leopold

    2015-10-01

    Adequate function of the retina is dependent on proper oxygen supply. In humans, the inner retina is oxygenated via the retinal circulation. We present a method to calculate total retinal oxygen extraction based on measurement of total retinal blood flow using dual-beam bidirectional Doppler optical coherence tomography and measurement of oxygen saturation by spectrophotometry. These measurements were done on 8 healthy subjects while breathing ambient room air and 100% oxygen. Total retinal blood flow was 44.3 ± 9.0 μl/min during baseline and decreased to 18.7 ± 4.2 μl/min during 100% oxygen breathing (P < 0.001) resulting in a pronounced decrease in retinal oxygen extraction from 2.33 ± 0.51 μl(O2)/min to 0.88 ± 0.14 μl(O2)/min during breathing of 100% oxygen. The method presented in this paper may have significant potential to study oxygen metabolism in hypoxic retinal diseases such as diabetic retinopathy.

  2. Retinal implants: a systematic review.

    PubMed

    Chuang, Alice T; Margo, Curtis E; Greenberg, Paul B

    2014-07-01

    Retinal implants present an innovative way of restoring sight in degenerative retinal diseases. Previous reviews of research progress were written by groups developing their own devices. This systematic review objectively compares selected models by examining publications describing five representative retinal prostheses: Argus II, Boston Retinal Implant Project, Epi-Ret 3, Intelligent Medical Implants (IMI) and Alpha-IMS (Retina Implant AG). Publications were analysed using three criteria for interim success: clinical availability, vision restoration potential and long-term biocompatibility. Clinical availability: Argus II is the only device with FDA approval. Argus II and Alpha-IMS have both received the European CE Marking. All others are in clinical trials, except the Boston Retinal Implant, which is in animal studies. Vision restoration: resolution theoretically correlates with electrode number. Among devices with external cameras, the Boston Retinal Implant leads with 100 electrodes, followed by Argus II with 60 electrodes and visual acuity of 20/1262. Instead of an external camera, Alpha-IMS uses a photodiode system dependent on natural eye movements and can deliver visual acuity up to 20/546. Long-term compatibility: IMI offers iterative learning; Epi-Ret 3 is a fully intraocular device; Alpha-IMS uses intraocular photosensitive elements. Merging the results of these three criteria, Alpha-IMS is the most likely to achieve long-term success decades later, beyond current clinical availability. PMID:24403565

  3. Concurrent hypopituitarism and leukemic retinopathy in a child with B-precursor acute lymphoblastic leukemia and isolated central nervous system relapse

    PubMed Central

    Wu, K.H.; Wu, H.P.; Lin, H.J.; Wang, C.H.; Chen, H.Y.; Weng, T.; Peng, C.T.; Chao, Y.H.

    2016-01-01

    Hypopituitarism in leukemia is very rare. In addition, central nervous system (cns) relapse and leukemic retinopathy in childhood acute lymphoblastic leukemia (all) have declined with the use of modern systemic chemotherapy that includes cns prophylaxis. Here, we report the case of a 4-year-old girl who received chemotherapy and intrathecal therapy without cns radiation after a diagnosis of B-precursor all without cns involvement. Three months after chemotherapy completion, she presented with lower-extremity weakness and was diagnosed with an isolated cns relapse. Concurrent hypopituitarism and leukemic retinopathy were also found. After receiving craniospinal radiotherapy and systemic chemotherapy, her retinopathy and vision improved. She is now in complete remission, and she is still on chemotherapy according to the guideline from the Pediatric Oncology Group. Although rare, hypopituitarism and leukemic retinopathy should be taken into consideration in patients with cns involvement by leukemia. PMID:27536191

  4. Effects of 5-HT-receptor and alpha 2-adrenoceptor ligands on the haemodynamic response to acute central hypovolaemia in conscious rabbits.

    PubMed Central

    Evans, R. G.; Haynes, J. M.; Ludbrook, J.

    1993-01-01

    1. We set out to elucidate the pharmacological mechanisms by which alpha 2-adrenoceptor and 5-HT-receptor ligands affect the haemodynamic response to acute central hypovolaemia in conscious rabbits. 2. Acute central hypovolaemia was produced by inflating an inferior vena caval cuff so that cardiac output fell at a constant rate of approximately 8.5% of its baseline level per min. 3. Drugs were administered into the fourth cerebral ventricle in either 154 mM NaCl (saline) or 20% w/v 2-hydroxypropyl-beta-cyclodextrin (beta-CDX). After vehicle treatments, the haemodynamic response to acute central hypovolaemia had the usual two phases. During Phase I, systemic vascular conductance fell in proportion to cardiac output so that mean arterial pressure fell by only 8 mmHg. Phase II commenced when cardiac output had fallen to approximately 60% of its baseline level, when vascular conductance rose abruptly and arterial pressure fell to < or = 40 mmHg. The haemodynamic response was not dependent on the vehicle used (saline or beta-CDX). 4. Methysergide delayed the occurrence of Phase II in a dose-dependent manner, and prevented it at a dose of 30- 600 nmol (geometric mean = 186 nmol). The effects and potency of methysergide were not dependent on the vehicle used, indicating that beta-CDX can be used as a vehicle for fourth ventricular administration of lipophilic drugs to conscious rabbits. Clonidine (10 nmol) reversed the effects of a critical dose of methysergide. 5. Phase II was also prevented by 8-hydroxy-2-(di-n-propylamino)tetralin (5-HT1A-selective agonist, geometric mean critical dose (range) = 13.1 (10-30) nmol), sumatriptan (5-HT1D-selective agonist, 72.1 (10-300) nmol), mesulergine (5-HT2/1C-selective antagonist, 173 (30-1000) nmol), idazoxan (alpha 2-adrenoceptor-selective antagonist, 548 (100-3000) nmol), and mianserin (5-HT2/1C-selective antagonist, 548 (100-3000) nmol). It was not affected by MDL 72222 (5-HT3-selective antagonist, 300 nmol) or ketanserin (5-HT2

  5. Central Agonism of GPR120 Acutely Inhibits Food Intake and Food Reward and Chronically Suppresses Anxiety-Like Behavior in Mice

    PubMed Central

    Fisette, Alexandre; Fernandes, Maria F.; Hryhorczuk, Cécile; Poitout, Vincent; Alquier, Thierry; Fulton, Stephanie

    2016-01-01

    Background: GPR120 (FFAR4) is a G-protein coupled receptor implicated in the development of obesity and the antiinflammatory and insulin-sensitizing effects of omega-3 (ω-3) polyunsaturated fatty acids. Increasing central ω-3 polyunsaturated fatty acid levels has been shown to have both anorectic and anxiolytic actions. Despite the strong clinical interest in GPR120, its role in the brain is largely unknown, and thus we sought to determine the impact of central GPR120 pharmacological activation on energy balance, food reward, and anxiety-like behavior. Methods: Male C57Bl/6 mice with intracerebroventricular cannulae received a single injection (0.1 or 1 µM) or continuous 2-week infusion (1 µM/d; mini-pump) of a GPR120 agonist or vehicle. Free-feeding intake, operant lever-pressing for palatable food, energy expenditure (indirect calorimetry), and body weight were measured. GPR120 mRNA expression was measured in pertinent brain areas. Anxiety-like behavior was assessed in the elevated-plus maze and open field test. Results: GPR120 agonist injections substantially reduced chow intake during 4 hours postinjection, suppressed the rewarding effects of high-fat/-sugar food, and blunted approach-avoidance behavior in the open field. Conversely, prolonged central GPR120 agonist infusions reduced anxiety-like behavior in the elevated-plus maze and open field, yet failed to affect free-feeding intake, energy expenditure, and body weight on a high-fat diet. Conclusion: Acute reductions in food intake and food reward suggest that GPR120 could mediate the effects of central ω-3 polyunsaturated fatty acids to inhibit appetite. The anxiolytic effect elicited by GPR120 agonist infusions favors the testing of compounds that can enter the brain to activate GPR120 for the mitigation of anxiety. PMID:26888796

  6. Increased Expression of Osteopontin in Retinal Degeneration Induced by Blue Light-Emitting Diode Exposure in Mice.

    PubMed

    Chang, Seung Wook; Kim, Hyung Il; Kim, Gyu Hyun; Park, Su Jin; Kim, In-Beom

    2016-01-01

    Osteopontin (OPN) is a multifunctional adhesive glycoprotein that is implicated in a variety of pro-inflammatory as well as neuroprotective and repair-promoting effects in the brain. As a first step towards understanding the role of OPN in retinal degeneration (RD), we examined changes in OPN expression in a mouse model of RD induced by exposure to a blue light-emitting diode (LED). RD was induced in BALB/c mice by exposure to a blue LED (460 nm) for 2 h. Apoptotic cell death was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. In order to investigate changes in OPN in RD, western blotting and immunohistochemistry were performed. Anti-OPN labeling was compared to that of anti-glial fibrillary acidic protein (GFAP), which is a commonly used marker for retinal injury or stress including inflammation. OPN expression in RD retinas markedly increased at 24 h after exposure, was sustained through 72 h, and subsided at 120 h. Increased OPN expression was observed co-localized with microglial cells in the outer nuclear layer (ONL), outer plexiform layer (OPL), and subretinal space. Expression was restricted to the central retina in which photoreceptor cell death occurred. Interestingly, OPN expression in the ONL/OPL was closely associated with microglia, whereas most of the OPN plaques observed in the subretinal space were not. Immunogold electron microscopy demonstrated that OPN was distributed throughout the cytoplasm of microglia and in nearby fragments of degenerating photoreceptors. In addition, we found that OPN was induced more acutely and with greater region specificity than GFAP. These results indicate that OPN may be a more useful marker for retinal injury or stress, and furthermore act as a microglial pro-inflammatory mediator and a phagocytosis-inducing opsonin in the subretinal space. Taken together, our data suggest that OPN plays an important role in the pathogenesis of RD. PMID:27504084

  7. Increased Expression of Osteopontin in Retinal Degeneration Induced by Blue Light-Emitting Diode Exposure in Mice

    PubMed Central

    Chang, Seung Wook; Kim, Hyung Il; Kim, Gyu Hyun; Park, Su Jin; Kim, In-Beom

    2016-01-01

    Osteopontin (OPN) is a multifunctional adhesive glycoprotein that is implicated in a variety of pro-inflammatory as well as neuroprotective and repair-promoting effects in the brain. As a first step towards understanding the role of OPN in retinal degeneration (RD), we examined changes in OPN expression in a mouse model of RD induced by exposure to a blue light-emitting diode (LED). RD was induced in BALB/c mice by exposure to a blue LED (460 nm) for 2 h. Apoptotic cell death was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. In order to investigate changes in OPN in RD, western blotting and immunohistochemistry were performed. Anti-OPN labeling was compared to that of anti-glial fibrillary acidic protein (GFAP), which is a commonly used marker for retinal injury or stress including inflammation. OPN expression in RD retinas markedly increased at 24 h after exposure, was sustained through 72 h, and subsided at 120 h. Increased OPN expression was observed co-localized with microglial cells in the outer nuclear layer (ONL), outer plexiform layer (OPL), and subretinal space. Expression was restricted to the central retina in which photoreceptor cell death occurred. Interestingly, OPN expression in the ONL/OPL was closely associated with microglia, whereas most of the OPN plaques observed in the subretinal space were not. Immunogold electron microscopy demonstrated that OPN was distributed throughout the cytoplasm of microglia and in nearby fragments of degenerating photoreceptors. In addition, we found that OPN was induced more acutely and with greater region specificity than GFAP. These results indicate that OPN may be a more useful marker for retinal injury or stress, and furthermore act as a microglial pro-inflammatory mediator and a phagocytosis-inducing opsonin in the subretinal space. Taken together, our data suggest that OPN plays an important role in the pathogenesis of RD. PMID:27504084

  8. Developing Cellular Therapies for Retinal Degenerative Diseases

    PubMed Central

    Bharti, Kapil; Rao, Mahendra; Hull, Sara Chandros; Stroncek, David; Brooks, Brian P.; Feigal, Ellen; van Meurs, Jan C.; Huang, Christene A.; Miller, Sheldon S.

    2014-01-01

    Biomedical advances in vision research have been greatly facilitated by the clinical accessibility of the visual system, its ease of experimental manipulation, and its ability to be functionally monitored in real time with noninvasive imaging techniques at the level of single cells and with quantitative end-point measures. A recent example is the development of stem cell–based therapies for degenerative eye diseases including AMD. Two phase I clinical trials using embryonic stem cell–derived RPE are already underway and several others using both pluripotent and multipotent adult stem cells are in earlier stages of development. These clinical trials will use a variety of cell types, including embryonic or induced pluripotent stem cell–derived RPE, bone marrow– or umbilical cord–derived mesenchymal stem cells, fetal neural or retinal progenitor cells, and adult RPE stem cells–derived RPE. Although quite distinct, these approaches, share common principles, concerns and issues across the clinical development pipeline. These considerations were a central part of the discussions at a recent National Eye Institute meeting on the development of cellular therapies for retinal degenerative disease. At this meeting, emphasis was placed on the general value of identifying and sharing information in the so-called “precompetitive space.” The utility of this behavior was described in terms of how it could allow us to remove road blocks in the clinical development pipeline, and more efficiently and economically move stem cell–based therapies for retinal degenerative diseases toward the clinic. Many of the ocular stem cell approaches we discuss are also being used more broadly, for nonocular conditions and therefore the model we develop here, using the precompetitive space, should benefit the entire scientific community. PMID:24573369

  9. Expansion of First-in-Class Drug Candidates That Sequester Toxic All-Trans-Retinal and Prevent Light-Induced Retinal Degeneration

    PubMed Central

    Zhang, Jianye; Dong, Zhiqian; Mundla, Sreenivasa Reddy; Hu, X. Eric; Seibel, William; Papoian, Ruben

    2015-01-01

    All-trans-retinal, a retinoid metabolite naturally produced upon photoreceptor light activation, is cytotoxic when present at elevated levels in the retina. To lower its toxicity, two experimentally validated methods have been developed involving inhibition of the retinoid cycle and sequestration of excess of all-trans-retinal by drugs containing a primary amine group. We identified the first-in-class drug candidates that transiently sequester this metabolite or slow down its production by inhibiting regeneration of the visual chromophore, 11-cis-retinal. Two enzymes are critical for retinoid recycling in the eye. Lecithin:retinol acyltransferase (LRAT) is the enzyme that traps vitamin A (all-trans-retinol) from the circulation and photoreceptor cells to produce the esterified substrate for retinoid isomerase (RPE65), which converts all-trans-retinyl ester into 11-cis-retinol. Here we investigated retinylamine and its derivatives to assess their inhibitor/substrate specificities for RPE65 and LRAT, mechanisms of action, potency, retention in the eye, and protection against acute light-induced retinal degeneration in mice. We correlated levels of visual cycle inhibition with retinal protective effects and outlined chemical boundaries for LRAT substrates and RPE65 inhibitors to obtain critical insights into therapeutic properties needed for retinal preservation. PMID:25538117

  10. Incidence and risk factors for Central Nervous System thrombosis in paediatric acute lymphoblastic leukaemia during intensive asparaginase treatment: a single-centre cohort study.

    PubMed

    Duarte, Ximo; Esteves, Susana; Neto, Ana M; Pereira, Filomena

    2016-07-01

    Central Nervous System (CNS) thrombosis is a complication of acute lymphoblastic leukaemia (ALL) treatment that is potentially associated with significant morbidity and neurological sequelae. Its presumably multifactorial aetiology is poorly characterized. We conducted a single-centre, retrospective cohort study on 346 ALL paediatric patients (1-16 years old) treated with asparaginase intensive Dana Farber Cancer Institute (DFCI) protocols from 1998 to 2011. The incidence, risk factors and outcome of CNS thrombosis were evaluated. CNS thrombosis occurred in 3·8% (13/346) of the patients (95% confidence interval 2·0-6·3%). Twelve events were diagnosed during intensification, all of which resolved within 2 weeks without neurological sequelae or significant impact in survival. Obesity (body mass index above 95th percentile) and asparaginase formulation were the only factors associated with CNS thrombosis, with an increase in the odds of event in obese patients [odds ratio (OR) = 3·37; P = 0·064] and a reduction in patients receiving Erwinia asparaginase (OR = 0·12; P = 0·018). No association could be demonstrated for age, gender, DFCI risk-group, ALL phenotype, steroid or doxorubicin use, central venous line use or CNS radiotherapy. CNS thrombosis is a rare but manageable adverse event without significant sequelae or detrimental effects in survival. Increased awareness is recommended in obese patients particularly during intensive asparaginase use. PMID:27018199

  11. Temperature controlled retinal photocoagulation

    NASA Astrophysics Data System (ADS)

    Schlott, Kerstin; Koinzer, Stefan; Baade, Alexander; Birngruber, Reginald; Roider, Johann; Brinkmann, Ralf

    2013-06-01

    Retinal photocoagulation lacks objective dosage in clinical use, thus the commonly applied lesions are too deep and strong, associated with pain reception and the risk of visual field defects and induction of choroidal neovascularisations. Optoacoustics allows real-time non-invasive temperature measurement in the fundus during photocoagulation by applying short probe laser pulses additionally to the treatment radiation, which excite the emission of ultrasonic waves. Due to the temperature dependence of the Grüneisen parameter, the amplitudes of the ultrasonic waves can be used to derive the temperature of the absorbing tissue. By measuring the temperatures in real-time and automatically controlling the irradiation by feedback to the treatment laser, the strength of the lesions can be defined. Different characteristic functions for the time and temperature dependent lesion sizes were used as rating curves for the treatment laser, stopping the irradiation automatically after a desired lesion size is achieved. The automatically produced lesion sizes are widely independent of the adjusted treatment laser power and individual absorption. This study was performed on anaesthetized rabbits and is a step towards a clinical trial with automatically controlled photocoagulation.

  12. Stem-loop binding protein is required for retinal cell proliferation, neurogenesis, and intraretinal axon pathfinding in zebrafish.

    PubMed

    Imai, Fumiyasu; Yoshizawa, Asuka; Matsuzaki, Ayako; Oguri, Eri; Araragi, Masato; Nishiwaki, Yuko; Masai, Ichiro

    2014-10-01

    In the developing retina, neurogenesis and cell differentiation are coupled with cell proliferation. However, molecular mechanisms that coordinate cell proliferation and differentiation are not fully understood. In this study, we found that retinal neurogenesis is severely delayed in the zebrafish stem-loop binding protein (slbp) mutant. SLBP binds to a stem-loop structure at the 3'-end of histone mRNAs, and regulates a replication-dependent synthesis and degradation of histone proteins. Retinal cell proliferation becomes slower in the slbp1 mutant, resulting in cessation of retinal stem cell proliferation. Although retinal stem cells cease proliferation by 2 days postfertilization (dpf) in the slbp mutant, retinal progenitor cells in the central retina continue to proliferate and generate neurons until at least 5dpf. We found that this progenitor proliferation depends on Notch signaling, suggesting that Notch signaling maintains retinal progenitor proliferation when faced with reduced SLBP activity. Thus, SLBP is required for retinal stem cell maintenance. SLBP and Notch signaling are required for retinal progenitor cell proliferation and subsequent neurogenesis. We also show that SLBP1 is required for intraretinal axon pathfinding, probably through morphogenesis of the optic stalk, which expresses attractant cues. Taken together, these data indicate important roles of SLBP in retinal development.

  13. Eye Morphology and Retinal Topography in Hummingbirds (Trochilidae: Aves).

    PubMed

    Lisney, Thomas J; Wylie, Douglas R; Kolominsky, Jeffrey; Iwaniuk, Andrew N

    2015-01-01

    Hummingbirds are a group of small, highly specialized birds that display a range of adaptations to their nectarivorous lifestyle. Vision plays a key role in hummingbird feeding and hovering behaviours, yet very little is known about the visual systems of these birds. In this study, we measured eye morphology in 5 hummingbird species. For 2 of these species, we used stereology and retinal whole mounts to study the topographic distribution of neurons in the ganglion cell layer. Eye morphology (expressed as the ratio of corneal diameter to eye transverse diameter) was similar among all 5 species and was within the range previously documented for diurnal birds. Retinal topography was similar in Amazilia tzacatl and Calypte anna. Both species had 2 specialized retinal regions of high neuron density: a central region located slightly dorso-nasal to the superior pole of the pecten, where densities reached ∼ 45,000 cells · mm(-2), and a temporal area with lower densities (38,000-39,000 cells · mm(-2)). A weak visual streak bridged the two high-density areas. A retina from Phaethornis superciliosus also had a central high-density area with a similar peak neuron density. Estimates of spatial resolving power for all 3 species were similar, at approximately 5-6 cycles · degree(-1). Retinal cross sections confirmed that the central high-density region in C. anna contains a fovea, but not the temporal area. We found no evidence of a second, less well-developed fovea located close to the temporal retina margin. The central and temporal areas of high neuron density allow for increased spatial resolution in the lateral and frontal visual fields, respectively. Increased resolution in the frontal field in particular may be important for mediating feeding behaviors such as aerial docking with flowers and catching small insects.

  14. Eye Morphology and Retinal Topography in Hummingbirds (Trochilidae: Aves).

    PubMed

    Lisney, Thomas J; Wylie, Douglas R; Kolominsky, Jeffrey; Iwaniuk, Andrew N

    2015-01-01

    Hummingbirds are a group of small, highly specialized birds that display a range of adaptations to their nectarivorous lifestyle. Vision plays a key role in hummingbird feeding and hovering behaviours, yet very little is known about the visual systems of these birds. In this study, we measured eye morphology in 5 hummingbird species. For 2 of these species, we used stereology and retinal whole mounts to study the topographic distribution of neurons in the ganglion cell layer. Eye morphology (expressed as the ratio of corneal diameter to eye transverse diameter) was similar among all 5 species and was within the range previously documented for diurnal birds. Retinal topography was similar in Amazilia tzacatl and Calypte anna. Both species had 2 specialized retinal regions of high neuron density: a central region located slightly dorso-nasal to the superior pole of the pecten, where densities reached ∼ 45,000 cells · mm(-2), and a temporal area with lower densities (38,000-39,000 cells · mm(-2)). A weak visual streak bridged the two high-density areas. A retina from Phaethornis superciliosus also had a central high-density area with a similar peak neuron density. Estimates of spatial resolving power for all 3 species were similar, at approximately 5-6 cycles · degree(-1). Retinal cross sections confirmed that the central high-density region in C. anna contains a fovea, but not the temporal area. We found no evidence of a second, less well-developed fovea located close to the temporal retina margin. The central and temporal areas of high neuron density allow for increased spatial resolution in the lateral and frontal visual fields, respectively. Increased resolution in the frontal field in particular may be important for mediating feeding behaviors such as aerial docking with flowers and catching small insects. PMID:26587582

  15. Lack of correlation of central nervous system inflammation and neuropathology with the development of seizures following acute virus infection.

    PubMed

    Libbey, Jane E; Kennett, Nikki J; Wilcox, Karen S; White, H Steve; Fujinami, Robert S

    2011-08-01

    Infection of C57BL/6 mice by the intracerebral route with the Daniels (DA) strain of Theiler's murine encephalomyelitis virus (TMEV) resulted in acute behavioral seizures in approximately 50% of the mice. By titration, the viral dose correlated with the percentage of mice developing seizures; however, neuropathological changes were similar over the dose range, and viral clearance from the brains occurred uniformly by day 14 postinfection (p.i.). Other TMEV strains and mutants (GDVII, WW, BeAn 8386 [BeAn], DApBL2M, H101) induced seizures in C57BL/6 mice to various degrees. The BeAn strain and DApBL2M mutant were similar to the DA strain in the percentages of mice developing seizures and neuropathological changes and in the extent of infected cells. The GDVII and WW strains caused 100% mortality by days 5 and 6 p.i., respectively, at which time neuropathological changes and neuronal infection were extensive. The H101 mutant induced seizures and caused 100% mortality by day 7 p.i.; however, only minor neuropathological changes and few infected cells were observed. Thus, in H101 mutant infections, it appears that elevated levels of cytokines, rather than neuronal cell death, play the dominant role in seizure induction.

  16. Impaired coronary and retinal vasomotor function to hyperoxia in Individuals with Type 2 diabetes

    PubMed Central

    Lott, Mary E.; Slocomb, Julia E.; Gao, Zhaohui; Gabbay, Robert A.; Quillen, David; Gardner, Thomas W.; Bettermann, Kerstin

    2016-01-01

    PURPOSE Adults with diabetes are at a high risk of developing coronary heart disease. The purpose of this study was to assess coronary artery vascular function non-invasively in individuals with and without Type 2 diabetes and to compare these coronary responses to another microvascular bed (i.e. retina). We hypothesized that individuals with diabetes would have impaired coronary reactivity and that these impairments would be associated with impairments in retinal reactivity. METHODS Coronary blood velocity (Transthoracic Doppler Echocardiography) and retinal diameters (Dynamic Vessel Analyzer) were measured continuously during five minutes of breathing 100% oxygen (i.e. hyperoxia) in 15 persons with Type 2 diabetes and 15 age-matched control subjects. Using fundus photographs, retinal vascular calibers were also measured (central retinal arteriole and venule equivalents). RESULTS Individuals with diabetes compared to controls had impaired coronary (−2.34 ± 16.64% vs. −14.27 ± 10.58%, P =0.03) and retinal (arteriole: −0.04 ± 3.34% vs. −3.65 ± 5.07%, P = 0.03; venule: −1.65 ± 3.68% vs. −5.23 ± 5.47%, P = 0.05) vasoconstrictor responses to hyperoxia, and smaller central arteriole-venule equivalent ratios (0.83 ± 0.07 vs. 0.90 ± 0.07, P = 0.014). Coronary reactivity was associated with central retinal arteriole equivalents (r = −0.516, P = 0.005) and retinal venular reactivity (r = 0.387, P = 0.034). CONCLUSION Diabetes impairs coronary and retinal microvascular function to hyperoxia. Impaired vasoconstrictor responses may be part of a systemic diabetic vasculopathy, which may contribute to adverse cardiovascular events in individuals with diabetes. PMID:26002545

  17. Chemical Exacerbation of Light-induced Retinal Degeneration in F344/N Rats in National Toxicology Program Rodent Bioassays.

    PubMed

    Yamashita, Haruhiro; Hoenerhoff, Mark J; Peddada, Shyamal D; Sills, Robert C; Pandiri, Arun R

    2016-08-01

    Retinal degeneration due to chronic ambient light exposure is a common spontaneous age-related finding in albino rats, but it can also be related to exposures associated with environmental chemicals and drugs. Typically, light-induced retinal degeneration has a central/hemispherical localization whereas chemical-induced retinal degeneration has a diffuse localization. This study was conducted to identify and characterize treatment-related retinal degeneration in National Toxicology Program rodent bioassays. A total of 3 chronic bioassays in F344/N rats (but not in B6C3F1/N mice) were identified that had treatment-related increases in retinal degeneration (kava kava extract, acrylamide, and leucomalachite green). A retrospective light microscopic evaluation of the retinas from rats in these 3 studies showed a dose-related increase in the frequencies of retinal degeneration, beginning with the loss of photoreceptor cells, followed by the inner nuclear layer cells. These dose-related increased frequencies of degenerative retinal lesions localized within the central/hemispherical region are suggestive of exacerbation of light-induced retinal degeneration. PMID:27230502

  18. [Unusual retinal abnormality: retinal hemorrhages related to scurvy].

    PubMed

    Errera, M-H; Dupas, B; Man, H; Gualino, V; Gaudric, A; Massin, P

    2011-03-01

    A diet restricted to rice and boiled fruit and vegetables leads to vitamin C deficiency. We describe the third case, to our knowledge, of retinal hemorrhages related to scurvy. Reduced bilateral visual acuity in a 50-year-old patient was associated with macrocytic anemia, denutrition, and cutaneous ecchymoses. Oral vitamin C treatment provided subjective clinical improvement and regression of the retinal hemorrhages on fundus examination, with no side effects. Vitamin C plays an important role in collagen stability in vascular and bone walls. PMID:21392843

  19. [Unusual retinal abnormality: retinal hemorrhages related to scurvy].

    PubMed

    Errera, M-H; Dupas, B; Man, H; Gualino, V; Gaudric, A; Massin, P

    2011-03-01

    A diet restricted to rice and boiled fruit and vegetables leads to vitamin C deficiency. We describe the third case, to our knowledge, of retinal hemorrhages related to scurvy. Reduced bilateral visual acuity in a 50-year-old patient was associated with macrocytic anemia, denutrition, and cutaneous ecchymoses. Oral vitamin C treatment provided subjective clinical improvement and regression of the retinal hemorrhages on fundus examination, with no side effects. Vitamin C plays an important role in collagen stability in vascular and bone walls.

  20. [Retinal vein occlusion management algorithm. Part 2. Macular edema].

    PubMed

    Budzinskaya, M V; Mazurina, N K; Egorov, A E; Kuroedov, A V; Loskutov, I A; Plyukhova, A A; Razik, S; Ryabtseva, A A; Simonova, S V

    2015-01-01

    Macular edema (ME) is the most common complication of both ischemic and nonischemic retinal vein occlusion (RVO). If the main trunk of the central retinal vein is involved, ME occurs in 100% of cases. According to the Central Vein Occlusion Study, in 65% of RVO and ME patients with baseline visual acuity (VA) of at least 0.5 (Golovin-Sivtsev chart) or higher, ME may resolve itself without treatment with subsequent VA improvement. Therefore, we recommend a 3-month treatment-free follow-up of nonischemic central RVO (CRVO) and ME patients with VA of 0.5 or higher. If no improvement is noted within this period, treatment is initiated. Immediate treatment is required in patients with cystic ME revealed by optical coherence tomography (OCT) and VA below 0.5. Ischemic maculopathy is extremely unpromising. Modified grid laser photocoagulation should not be used as monotherapy for macular edema. Repeated corticosteroid (Ozurdex) and/or anti-VEGF (ranibizumab, aflibercept) intravitreal injections are considered the first choice treatment for ME in CRVO patients. Efficiency assessments should include monthly OCT. For persistent ME, intravitreal therapy can be supplemented by laser retinal photocoagulation (panretinal or modified grid). Anti-VEGF treatment schemes should be adjusted in BRVO patients as most of their edemas are self-limiting. Of laser photocoagulation techniques, only modified grid is used. PMID:26977728

  1. An excitatory cortical feedback loop gates retinal wave transmission in rodent thalamus

    PubMed Central

    Murata, Yasunobu; Colonnese, Matthew T

    2016-01-01

    Spontaneous retinal waves are critical for the development of receptive fields in visual thalamus (LGN) and cortex (VC). Despite a detailed understanding of the circuit specializations in retina that generate waves, whether central circuit specializations also exist to control their propagation through visual pathways of the brain is unknown. Here we identify a developmentally transient, corticothalamic amplification of retinal drive to thalamus as a mechanism for retinal wave transmission in the infant rat brain. During the period of retinal waves, corticothalamic connections excite LGN, rather than driving feedforward inhibition as observed in the adult. This creates an excitatory feedback loop that gates retinal wave transmission through the LGN. This cortical multiplication of retinal wave input ends just prior to eye-opening, as cortex begins to inhibit LGN. Our results show that the early retino-thalamo-cortical circuit uses developmentally specialized feedback amplification to ensure powerful, high-fidelity transmission of retinal activity despite immature connectivity. DOI: http://dx.doi.org/10.7554/eLife.18816.001 PMID:27725086

  2. Summarising the retinal vascular calibres in healthy, diabetic and diabetic retinopathy eyes.

    PubMed

    Leontidis, Georgios; Al-Diri, Bashir; Hunter, Andrew

    2016-05-01

    Retinal vessel calibre has been found to be an important biomarker of several retinal diseases, including diabetic retinopathy (DR). Quantifying the retinal vessel calibres is an important step for estimating the central retinal artery and vein equivalents. In this study, an alternative method to the already established branching coefficient (BC) is proposed for summarising the vessel calibres in retinal junctions. This new method combines the mean diameter ratio with an alternative to Murray׳s cube law exponent, derived by the fractal dimension,experimentally, and the branch exponent of cerebral vessels, as has been suggested in previous studies with blood flow modelling. For the above calculations, retinal images from healthy, diabetic and DR subjects were used. In addition, the above method was compared with the BC and was also applied to the evaluation of arteriovenous ratio as a biomarker of progression from diabetes to DR in four consecutive years, i.e. three/two/one years before the onset of DR and the first year of DR. Moreover, the retinal arteries and veins around the optic nerve head were also evaluated. The new approach quantifies the vessels more accurately. The decrease in terms of the mean absolute percentage error was between 0.24% and 0.49%, extending at the same time the quantification beyond healthy subjects.

  3. A randomized, double-masked study on the treatment of retinal vein occlusion with troxerutin.

    PubMed

    Glacet-Bernard, A; Coscas, G; Chabanel, A; Zourdani, A; Lelong, F; Samama, M M

    1994-10-15

    Hemorheologic factors probably play a role in the pathogenesis and prognosis of retinal vein occlusion. Accordingly, we designed a prospective, randomized, double-masked study to evaluate the effect of troxerutin, a rheologic drug, on retinal vein occlusion. Fifty-three patients were included, 27 with central retinal vein occlusion and 26 with branch retinal vein occlusion. They were randomly assigned for treatment with either troxerutin or a placebo. All subjects were similar in age, gender, associated diseases, hemorheologic values, and clinical severity of the retinal vein occlusion. At the end of follow-up, members of the troxerutin-treated group, as compared with the placebo group, showed significant improvement in visual acuity (P = .03), macular threshold (P = .01), retinal circulation times (P = .04), and macular edema (P = .05). Furthermore, they had diminished progression of ischemia (P = .05) and decreased red blood cell aggregability (P = .006) when compared with the controls. These encouraging preliminary results obtained with a rheologic treatment attest to the pathogenic role of blood viscosity in retinal vein occlusion and suggest that a large-scale randomized study should be conducted.

  4. [Retinal vein occlusion management algorithm. Part 3. Neovascular complications].

    PubMed

    Budzinskaya, M V; Mazurina, N K; Egorov, A E; Kuroedov, A V; Loskutov, I A; Plyukhova, A A; Razik, S; Ryabtseva, A A; Simonova, S V

    2015-01-01

    Neovascular complications severity in central/branch retinal vein occlusion (RVO) correlates with the level of occlusion and the degree of retinal perfusion disturbance. Large areas of retinal non-perfusion (more than half of the total retinal area) are associated with the risk for posterior segment neovascularization as high as 33% and for neovascular glaucoma - 45%. Over the past 30 years there has been an evident declining tendency of neovascular complications rates in the natural course of RVO. In ischemic RVO, anterior segment neovascularization is more aggressive than posterior. Neovascular glaucoma usually develops within the first 6 months of disease and correlates with uncontrolled arterial hypertension. Panretinal photocoagulation (PRP) is a standard treatment for anterior and posterior segment neovascularization in RVO patients. Anti-VEGF agents, if used as monotherapy, lead to rapid, however, short-term remission. Combination therapy, that is anti-VEGF injections and PRP, is the most effective. Intravitreal steroids have demonstrated no effect on ocular neovascularization. If PRP cannot be performed and intraocular pressure levels remain high, one should consider glaucoma drainage implant surgery. Preventive measures for neovascular complications that have proved effective so far include regular follow-ups, individually scheduled intravitreal injections, and PRP for large zones of ischemia. PMID:26977729

  5. Photoreceptor cell death and rescue in retinal detachment and degenerations

    PubMed Central

    Murakami, Yusuke; Notomi, Shoji; Hisatomi, Toshio; Nakazawa, Toru; Ishibashi, Tatsuro; Miller, Joan W.; Vavvas, Demetrios G.

    2013-01-01

    Photoreceptor cell death is the ultimate cause of vision loss in various retinal disorders, including retinal detachment (RD). Photoreceptor cell death has been thought to occur mainly through apoptosis, which is the most characterized form of programmed cell death. The caspase family of cysteine proteases plays a central role for inducing apoptosis, and in experimental models of RD, dying photoreceptor cells exhibit caspase activation; however, there is a paradox that caspase inhibition alone does not provide a sufficient protection against photoreceptor cell loss, suggesting that other mechanisms of cell death are involved. Recent accumulating evidence demonstrates that non-apoptotic forms of cell death, such as autophagy and necrosis, are also regulated by specific molecular machinery, such as those mediated by autophagy-related proteins and receptor-interacting protein kinases, respectively. Here we summarize the current knowledge of cell death signaling and its roles in photoreceptor cell death after RD and other retinal degenerative diseases. A body of studies indicate that not only apoptotic but also autophagic and necrotic signaling are involved in photoreceptor cell death, and that combined targeting of these pathways may be an effective neuroprotective strategy for retinal diseases associated with photoreceptor cell loss. PMID:23994436

  6. Effects of acute tryptophan depletion on central processing of CT-targeted and discriminatory touch in humans.

    PubMed

    Trotter, Paula Diane; McGlone, Francis; McKie, Shane; McFarquhar, Martyn; Elliott, Rebecca; Walker, Susannah Claire; Deakin, John Francis William

    2016-08-01

    C-tactile afferents (CTs) are slowly conducting nerve fibres, present only in hairy skin. They are optimally activated by slow, gentle stroking touch, such as those experienced during a caress. CT stimulation activates affective processing brain regions, alluding to their role in affective touch perception. We tested a theory that CT-activating touch engages the pro-social functions of serotonin, by determining whether reducing serotonin, through acute tryptophan depletion, diminishes subjective pleasantness and affective brain responses to gentle touch. A tryptophan depleting amino acid drink was administered to 16 healthy females, with a further 14 receiving a control drink. After 4 h, participants underwent an fMRI scan, during which time CT-innervated forearm skin and CT non-innervated finger skin was stroked with three brushes of differing texture, at CT-optimal force and velocity. Pleasantness ratings were obtained post scanning. The control group showed a greater response in ipsilateral orbitofrontal cortex to CT-activating forearm touch compared to touch to the finger where CTs are absent. This differential response was not present in the tryptophan depleted group. This interaction effect was significant. In addition, control participants showed a differential primary somatosensory cortex response to brush texture applied to the finger, a purely discriminatory touch response, which was not observed in the tryptophan depleted group. This interaction effect was also significant. Pleasantness ratings were similar across treatment groups. These results implicate serotonin in the differentiation between CT-activating and purely discriminatory touch responses. Such effects could contribute to some of the social abnormalities seen in psychiatric disorders associated with abnormal serotonin function. PMID:27307373

  7. Effects of acute tryptophan depletion on central processing of CT-targeted and discriminatory touch in humans.

    PubMed

    Trotter, Paula Diane; McGlone, Francis; McKie, Shane; McFarquhar, Martyn; Elliott, Rebecca; Walker, Susannah Claire; Deakin, John Francis William

    2016-08-01

    C-tactile afferents (CTs) are slowly conducting nerve fibres, present only in hairy skin. They are optimally activated by slow, gentle stroking touch, such as those experienced during a caress. CT stimulation activates affective processing brain regions, alluding to their role in affective touch perception. We tested a theory that CT-activating touch engages the pro-social functions of serotonin, by determining whether reducing serotonin, through acute tryptophan depletion, diminishes subjective pleasantness and affective brain responses to gentle touch. A tryptophan depleting amino acid drink was administered to 16 healthy females, with a further 14 receiving a control drink. After 4 h, participants underwent an fMRI scan, during which time CT-innervated forearm skin and CT non-innervated finger skin was stroked with three brushes of differing texture, at CT-optimal force and velocity. Pleasantness ratings were obtained post scanning. The control group showed a greater response in ipsilateral orbitofrontal cortex to CT-activating forearm touch compared to touch to the finger where CTs are absent. This differential response was not present in the tryptophan depleted group. This interaction effect was significant. In addition, control participants showed a differential primary somatosensory cortex response to brush texture applied to the finger, a purely discriminatory touch response, which was not observed in the tryptophan depleted group. This interaction effect was also significant. Pleasantness ratings were similar across treatment groups. These results implicate serotonin in the differentiation between CT-activating and purely discriminatory touch responses. Such effects could contribute to some of the social abnormalities seen in psychiatric disorders associated with abnormal serotonin function.

  8. Transcorneal Electrical Stimulation Therapy for Retinal Disease

    ClinicalTrials.gov

    2012-05-03

    Retinitis Pigmentosa; Macula Off; Primary Open Angle Glaucoma; Hereditary Macular Degeneration; Treated Retina Detachment; Retinal Artery Occlusion; Retinal Vein Occlusion; Non-Arthritic-Anterior-Ischemic Optic-Neuropathy; Hereditary Autosomal Dominant Optic Atrophy; Dry Age Related Macular Degeneration; Ischemic Macula Edema

  9. Retinal spot size with wavelength

    NASA Astrophysics Data System (ADS)

    Rockwell, Benjamin A.; Hammer, Daniel X.; Kennedy, Paul K.; Amnotte, Rodney E.; Eilert, Brent; Druessel, Jeffrey J.; Payne, Dale J.; Phillips, Shana L.; Stolarski, David J.; Noojin, Gary D.; Thomas, Robert J.; Cain, Clarence P.

    1997-06-01

    We have made an indirect in-vivo determination of spot size focusing in the rhesus monkey model. Measurement of the laser induced breakdown threshold both in-vitro and in-vivo allow correlation and assignment of a spot size after focusing through the living eye. We discuss and analyze the results and show how trends in minimum visible lesion data should be assessed in light of chromatic aberration. National laser safety standards are based on minimal visual lesion (MVL) threshold studies in different animal models. The energy required for a retinal lesion depends upon may parameters including wavelength and retinal spot size. We attempt to explain trends in reported MVL threshold studies using a model of the eye which allows calculation of changes in retinal spot size due to chromatic aberration.

  10. Clinical Trials in Retinal Dystrophies.

    PubMed

    Grob, Seanna R; Finn, Avni; Papakostas, Thanos D; Eliott, Dean

    2016-01-01

    Research development is burgeoning for genetic and cellular therapy for retinal dystrophies. These dystrophies are the focus of many research efforts due to the unique biology and accessibility of the eye, the transformative advances in ocular imaging technology that allows for in vivo monitoring, and the potential benefit people would gain from success in the field - the gift of renewed sight. Progress in the field has revealed the immense complexity of retinal dystrophies and the challenges faced by researchers in the development of this technology. This study reviews the current trials and advancements in genetic and cellular therapy in the treatment of retinal dystrophies and also discusses the current and potential future challenges. PMID:26957839

  11. Exploring the retinal connectome

    PubMed Central

    Anderson, James R.; Jones, Bryan W.; Watt, Carl B.; Shaw, Margaret V.; Yang, Jia-Hui; DeMill, David; Lauritzen, James S.; Lin, Yanhua; Rapp, Kevin D.; Mastronarde, David; Koshevoy, Pavel; Grimm, Bradley; Tasdizen, Tolga; Whitaker, Ross

    2011-01-01

    Purpose A connectome is a comprehensive description of synaptic connectivity for a neural domain. Our goal was to produce a connectome data set for the inner plexiform layer of the mammalian retina. This paper describes our first retinal connectome, validates the method, and provides key initial findings. Methods We acquired and assembled a 16.5 terabyte connectome data set RC1 for the rabbit retina at ≈2 nm resolution using automated transmission electron microscope imaging, automated mosaicking, and automated volume registration. RC1 represents a column of tissue 0.25 mm in diameter, spanning the inner nuclear, inner plexiform, and ganglion cell layers. To enhance ultrastructural tracing, we included molecular markers for 4-aminobutyrate (GABA), glutamate, glycine, taurine, glutamine, and the in vivo activity marker, 1-amino-4-guanidobutane. This enabled us to distinguish GABAergic and glycinergic amacrine cells; to identify ON bipolar cells coupled to glycinergic cells; and to discriminate different kinds of bipolar, amacrine, and ganglion cells based on their molecular signatures and activity. The data set was explored and annotated with Viking, our multiuser navigation tool. Annotations were exported to additional applications to render cells, visualize network graphs, and query the database. Results Exploration of RC1 showed that the 2 nm resolution readily recapitulated well known connections and revealed several new features of retinal organization: (1) The well known AII amacrine cell pathway displayed more complexity than previously reported, with no less than 17 distinct signaling modes, including ribbon synapse inputs from OFF bipolar cells, wide-field ON cone bipolar cells and rod bipolar cells, and extensive input from cone-pathway amacrine cells. (2) The axons of most cone bipolar cells formed a distinct signal integration compartment, with ON cone bipolar cell axonal synapses targeting diverse cell types. Both ON and OFF bipolar cells receive

  12. Rat retinal transcriptome

    PubMed Central

    Kozhevnikova, Oyuna S.; Korbolina, Elena E.; Ershov, Nikita I.; Kolosova, Natalia G.

    2013-01-01

    Pathogenesis of age-related macular degeneration (AMD), the leading cause of vision loss in the elderly, remains poorly understood due to the paucity of animal models that fully replicate the human disease. Recently, we showed that senescence-accelerated OXYS rats develop a retinopathy similar to human AMD. To identify alterations in response to normal aging and progression of AMD-like retinopathy, we compared gene expression profiles of retina from 3- and 18-mo-old OXYS and control Wistar rats by means of high-throughput RNA sequencing (RNA-Seq). We identified 160 and 146 age-regulated genes in Wistar and OXYS retinas, respectively. The majority of them are related to the immune system and extracellular matrix turnover. Only 24 age-regulated genes were common for the two strains, suggestive of different rates and mechanisms of aging. Over 600 genes showed significant differences in expression between the two strains. These genes are involved in disease-associated pathways such as immune response, inflammation, apoptosis, Ca2+ homeostasis and oxidative stress. The altered expression for selected genes was confirmed by qRT-PCR analysis. To our knowledge, this study represents the first analysis of retinal transcriptome from young and old rats with biologic replicates generated by RNA-Seq technology. We can conclude that the development of AMD-like retinopathy in OXYS rats is associated with an imbalance in immune and inflammatory responses. Aging alters the expression profile of numerous genes in the retina, and the genetic background of OXYS rats has a profound impact on the development of AMD-like retinopathy. PMID:23656783

  13. The time of resolution and the rate of recurrence in acute central serous chorioretinopathy following spontaneous resolution and low-fluence photodynamic therapy: a case-control study.

    PubMed

    Ozkaya, A; Alkin, Z; Ozveren, M; Yazici, A T; Taskapili, M

    2016-07-01

    PurposeTo evaluate the resolution time and the recurrence rate of acute central serous chorioretinopathy (CSC) after spontaneous resolution and low-fluence photodynamic therapy (PDT).MethodsCase-control study: The CSC patients who were admitted to our clinic for the first time were included. No treatment was given during the first 6 months. Patients were treated with PDT after 6 months from the initial signs of the disease, if they did not show any sign of resolution. The patients who showed a significant decrease in subretinal fluid after month 6 were not scheduled for PDT. The primary outcomes were the resolution time and the recurrence rate after the first episode. Secondary outcome measures were the change in BCVA and CRT during the follow up.ResultsA total of 77 consecutive eyes of 77 patients were included, 41 eyes (53.2%) with spontaneously resolved CSC and 36 eyes (46.8%) with PDT-treated CSC. The initial resolution time was 4.1±3.2 months in spontaneous resolution group, and 8.1±0.8 months in PDT group, respectively (P<0.001). The recurrence rate was 51.2% in spontaneous resolution group, and 25% in PDT group (P=0.01). The change in BCVA from baseline to the last follow-up visit was statistically significant in both groups (P=0.002, P=0.003, respectively). The change in CRT from baseline to the last follow up was also statistically significant in both groups (P=0.002, P=0.003, respectively).ConclusionsThe recurrence rate of acute CSC was lower in PDT-treated patients than the spontaneously resolved patients.

  14. New Wrinkles in Retinal Densitometry

    PubMed Central

    Masella, Benjamin D.; Hunter, Jennifer J.; Williams, David R.

    2014-01-01

    Purpose. Retinal densitometry provides objective information about retinal function. But, a number of factors, including retinal reflectance changes that are not directly related to photopigment depletion, complicate its interpretation. We explore these factors and suggest a method to minimize their impact. Methods. An adaptive optics scanning light ophthalmoscope (AOSLO) was used to measure changes in photoreceptor reflectance in monkeys before and after photopigment bleaching with 514-nm light. Reflectance measurements at 514 nm and 794 nm were recorded simultaneously. Several methods of normalization to extract the apparent optical density of the photopigment were compared. Results. We identified stimulus-related fluctuations in 794-nm reflectance that are not associated with photopigment absorptance and occur in both rods and cones. These changes had a magnitude approaching those associated directly with pigment depletion, precluding the use of infrared reflectance for normalization. We used a spatial normalization method instead, which avoided the fluctuations in the near infrared, as well as a confocal AOSLO designed to minimize light from layers other than the receptors. However, these methods produced a surprisingly low estimate of the apparent rhodopsin density (animal 1: 0.073 ± 0.006, animal 2: 0.032 ± 0.003). Conclusions. These results confirm earlier observations that changes in photopigment absorption are not the only source of retinal reflectance change during dark adaptation. It appears that the stray light that has historically reduced the apparent density of cone photopigment in retinal densitometry arises predominantly from layers near the photoreceptors themselves. Despite these complications, this method provides a valuable, objective measure of retinal function. PMID:25316726

  15. Retinal Image Quality During Accommodation

    PubMed Central

    López-Gil, N.; Martin, J.; Liu, T.; Bradley, A.; Díaz-Muñoz, D.; Thibos, L.

    2013-01-01

    Purpose We asked if retinal image quality is maximum during accommodation, or sub-optimal due to accommodative error, when subjects perform an acuity task. Methods Subjects viewed a monochromatic (552nm), high-contrast letter target placed at various viewing distances. Wavefront aberrations of the accommodating eye were measured near the endpoint of an acuity staircase paradigm. Refractive state, defined as the optimum target vergence for maximising retinal image quality, was computed by through-focus wavefront analysis to find the power of the virtual correcting lens that maximizes visual Strehl ratio. Results Despite changes in ocular aberrations and pupil size during binocular viewing, retinal image quality and visual acuity typically remain high for all target vergences. When accommodative errors lead to sub-optimal retinal image quality, acuity and measured image quality both decline. However, the effect of accommodation errors of on visual acuity are mitigated by pupillary constriction associated with accommodation and binocular convergence and also to binocular summation of dissimilar retinal image blur. Under monocular viewing conditions some subjects displayed significant accommodative lag that reduced visual performance, an effect that was exacerbated by pharmacological dilation of the pupil. Conclusions Spurious measurement of accommodative error can be avoided when the image quality metric used to determine refractive state is compatible with the focusing criteria used by the visual system to control accommodation. Real focusing errors of the accommodating eye do not necessarily produce a reliably measurable loss of image quality or clinically significant loss of visual performance, probably because of increased depth-of-focus due to pupil constriction. When retinal image quality is close to maximum achievable (given the eye’s higher-order aberrations), acuity is also near maximum. A combination of accommodative lag, reduced image quality, and reduced

  16. Retinal Optical Coherence Tomography Imaging

    NASA Astrophysics Data System (ADS)

    Drexler, Wolfgang; Fujimoto, James G.

    The eye is essentially transparent, transmitting light with only minimal optical attenuation and scattering providing easy optical access to the anterior segment as well as the retina. For this reason, ophthalmic and especially retinal imaging has been not only the first but also most successful clinical application for optical coherence tomography (OCT). This chapter focuses on the development of OCT technology for retinal imaging. OCT has significantly improved the potential for early diagnosis, understanding of retinal disease pathogenesis, as well as monitoring disease progression and response to therapy. Development of ultrabroad bandwidth light sources and high-speed detection techniques has enabled significant improvements in ophthalmic OCT imaging performance, demonstrating the potential of three-dimensional, ultrahigh-resolution OCT (UHR OCT) to perform noninvasive optical biopsy of the living human retina, i.e., the in vivo visualization of microstructural, intraretinal morphology in situ approaching the resolution of conventional histopathology. Significant improvements in axial resolution and speed not only enable three-dimensional rendering of retinal volumes but also high-definition, two-dimensional tomograms, topographic thickness maps of all major intraretinal layers, as well as volumetric quantification of pathologic intraretinal changes. These advances in OCT technology have also been successfully applied in several animal models of retinal pathologies. The development of light sources emitting at alternative wavelengths, e.g., around #1,060 nm, not only enabled three-dimensional OCT imaging with enhanced choroidal visualization but also improved OCT performance in cataract patients due to reduced scattering losses in this wavelength region. Adaptive optics using deformable mirror technology, with unique high stroke to correct higher-order ocular aberrations, with specially designed optics to compensate chromatic aberration of the human eye, in

  17. Comparative retinal physiology in anthropoids.

    PubMed

    Kremers, J; Lee, B B

    1998-11-01

    During the last decade it has become clear that colour vision in platyrrhines (New World monkeys) differs from the uniform trichromatic pattern normally found in catarrhines (Old World monkeys, apes and human). Colour vision in most platyrrhine species is polymorphic, with many dichromatic individuals. The comparison of response properties in retinal ganglion cells and lateral geniculate cells between catarrhines and playrrhines elucidates how the evolution of trichromatic colour vision influenced the post-receptoral processing. We find that spatial and temporal processing is very similar in the platyrrhine and catarrhine retina, strongly suggesting that the retinal structure and function, found in living anthropoids, was already present in their common ancestor. PMID:9893846

  18. Retinitis pigmentosa in southern Africa.

    PubMed

    Greenberg, J; Bartmann, L; Ramesar, R; Beighton, P

    1993-11-01

    Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal disorders which are a common cause of genetic blindness. The relative frequencies of the different forms of RP in South Africa, as determined from the register at the DNA banking centre for RP at the Department of Human Genetics, University of Cape Town, are presented and discussed. Of the 125 families analysed, 29 (23%) showed autosomal dominant, 33 (27%) autosomal recessive and 3 (3%) X-linked inheritance. In 10 families the pedigree data were insufficient to allow accurate genetic subtyping and a further 50 patients were sporadic without a family history of RP or other syndromic features which would allow categorization.

  19. Acute up-regulation of the rat brain somatostatin receptor-effector system by leptin is related to activation of insulin signaling and may counteract central leptin actions.

    PubMed

    Perianes-Cachero, A; Burgos-Ramos, E; Puebla-Jiménez, L; Canelles, S; Frago, L M; Hervás-Aguilar, A; de Frutos, S; Toledo-Lobo, M V; Mela, V; Viveros, M P; Argente, J; Chowen, J A; Arilla-Ferreiro, E; Barrios, V

    2013-11-12

    Leptin and somatostatin (SRIF) have opposite effects on food seeking and ingestive behaviors, functions partially regulated by the frontoparietal cortex and hippocampus. Although it is known that the acute suppression of food intake mediated by leptin decreases with time, the counter-regulatory mechanisms remain unclear. Our aims were to analyze the effect of acute central leptin infusion on the SRIF receptor-effector system in these areas and the implication of related intracellular signaling mechanisms in this response. We studied 20 adult male Wister rats including controls and those treated intracerebroventricularly with a single dose of 5 μg of leptin and sacrificed 1 or 6h later. Density of SRIF receptors was unchanged at 1h, whereas leptin increased the density of SRIF receptors at 6h, which was correlated with an elevated capacity of SRIF to inhibit forskolin-stimulated adenylyl cyclase activity in both areas. The functional capacity of SRIF receptors was unaltered as cell membrane levels of αi1 and αi2 subunits of G inhibitory proteins were unaffected in both brain areas. The increased density of SRIF receptors was due to enhanced SRIF receptor subtype 2 (sst2) protein levels that correlated with higher mRNA levels for this receptor. These changes in sst2 mRNA levels were concomitant with increased activation of the insulin signaling, c-Jun and cyclic AMP response element-binding protein (CREB); however, activation of signal transducer and activator of transcription 3 was reduced in the cortex and unchanged in the hippocampus and suppressor of cytokine signaling 3 remained unchanged in these areas. In addition, the leptin antagonist L39A/D40A/F41A blocked the leptin-induced changes in SRIF receptors, leptin signaling and CREB activation. In conclusion, increased activation of insulin signaling after leptin infusion is related to acute up-regulation of the SRIF receptor-effector system that may antagonize short-term leptin actions in the rat brain.

  20. [Complications in the central nervous system during chemotherapy for childhood acute lymphoblastic leukemia: JACLS ALL-02 study].

    PubMed

    Umeda, Katsutsugu; Yoshida, Makoto; Suzuki, Nobuhiro; Endo, Mikiya; Sato, Atsushi; Hori, Hiroki; Isogai, Mitsuharu; Matsumoto, Kimikazu; Hara, Jun-iIchi; Hasegawa, Daiichiro; Hashii, Yoshiko; Chayama, Kosuke; Miyaji, Ryousuke; Nishimura, Shin-ichiro; Tanizawa, Akihiko; Uami, Ikuya; Horibe, Keizo; Wakazono, Yoshihiro; Yagi, Keiko

    2007-03-01

    We evaluated central nervous system (CNS) complications treated under the ALL-02 protocol of the Japan Association of Childhood Leukemia Study (JACLS) from April 2002 to March 2005. According to NCI Toxicity Criteria, 17 events of grade 3 and 4 CNS complications were reported in 15 out of 541 patients. Out of these CNS complications, leukoencephalopathy was seen in 5 patients; seizure in 5; cerebrovascular disease in 3; conscious disturbance in 2; and hypertensive encephalopathy and reversible posterior leukoencephalopathy syndrome in one patient each. The complications were intensively observed during induction therapy and the last of the early phase chemotherapy. The protocol treatment was stopped or modified in most patients after CNS complications. MRI imaging demonstrated no improvement in one patient with leukoencephalopathy who developed an isolated CNS relapse, while other patients were alive and remain in their first complete remission without any neurological sequelae. Further studies will be required to analyze risk factors for CNS complications during chemotherapy not accompanied by irradiation and to establish alternative treatments after the appearance of such CNS complications.

  1. Disruption of neuroendocrine stress responses to acute ferret odor by medial, but not central amygdala lesions in rats

    PubMed Central

    Masini, Cher V.; Sasse, Sarah K.; Garcia, Robert J.; Nyhuis, Tara J.; Day, Heidi E.W.; Campeau, Serge

    2009-01-01

    Investigations of the neural pathways associated with responses to predators have implicated the medial amygdala (MeA) as an important region involved in defensive behaviors. To our knowledge, however, the involvement of the MeA in neuroendocrine responses to predator odor exposure has not been investigated. Therefore, the present study examined the effects of MeA disruption in rats exposed to ferret or control odor on hypothalamo-pituitary-adrenocortical (HPA) axis activation. Bilateral lesions of the MeA were made in Sprague- Dawley rats with the neurotoxin ibotenic acid (10 µg/µl; 0.3 µl /side). As a control for regional specificity, additional groups of rats were given lesions in the central amygdala (CeA). One week after recovery, the rats were exposed to ferret or strawberry control towels in small cages to examine HPA axis responses as determined by plasma corticosterone and adrenocorticotropin hormone (ACTH) levels. Rats with complete bilateral MeA but not CeA lesions displayed significantly less corticosterone and ACTH release compared to sham-operated control rats only in the ferret odor conditions. These results suggest that the MeA is an important structure involved in the HPA axis responses to predator odors, in support of previous studies investigating behavioral responses under similar conditions. PMID:19615352

  2. Haemorheological changes in patients with retinal vein occlusion after isovolaemic haemodilution.

    PubMed Central

    Wiek, J; Schade, M; Wiederholt, M; Arntz, H R; Hansen, L L

    1990-01-01

    In 83 patients with central retinal vein occlusion and branch vein occlusion we measured the haematocrit (HCT), plasma viscosity (PV), red cell aggregation (RCA), red cell filterability (RCF) and apparent whole blood viscosity (WBV). A control group (n = 41) was matched for sex, age, and cardiovascular risk factors. Measurements were performed before and after treatment with isovolaemic haemodilution (IHD). We found no significant differences between patients with retinal vein occlusion (RVO) and control subjects in haematocrit, plasma viscosity, red cell aggregation, and red cell filterability and no increased whole blood viscosity in the patient group. Patients with ischaemic retinal vein occlusion and non-ischaemic retinal vein occlusion did not show different haemorheological parameters either. After treatment with haemodilution, only the haematocrit and whole blood viscosity were significantly decreased, and there were no changes in plasma viscosity, red cell aggregation or red cell filterability. PMID:2223704

  3. Preservation of retinal structure and function after cilioretinal artery occlusion: a case report.

    PubMed

    Brown, Craig J

    2016-01-01

    Cilioretinal artery occlusion is a cause of sudden, often catastrophic loss of central vision. There are no established effective treatments. Recently, a patient presented 24 hours after a cilioretinal artery occlusion, following a cardiac catheterization prior to which her blood thinners had been discontinued. Lacking an effective way to address the severe retinal ischemic oxidative stress, she was offered, under compassionate use, a multivitamin complex designed to address retinal ischemia and oxidative stress. Significant components of this product are L-methylfolate and n-acetyl cysteine. The patient experienced a rapid unexpected improvement in vision and preservation of retinal structure, suggesting that marked improvement in retinal artery occlusions outcomes may be possible as late as 24 hours postocclusion. This is the third reported case of cilioretinal artery occlusion associated with cardiac catheterization. PMID:26929671

  4. [Retinal vascular changes--predictive and prognostic factor in systemic disease].

    PubMed

    Vicol, Anca Delia; Bogdănici, Tudor; Bogdănici, Camelia

    2014-01-01

    The retinal circulation represents a unique window for the direct, non invazive in vivo status of the systemic mycrocirculation, but it can also offer scientific support for theories related strictly to ocular diseases, such as glaucoma (vascular theory). The interaction between intraocular pressure, retinal vessels and cerebrospinal fluid pressure located at the retrolaminar part of the optic nerve has been of great interest for both ophthalmologists or neuroscientists, both clinicians and researchers. The retinal vascular bed has structural and functional similarities with other vascular teritories such as Central Nervous System (CNS), kidneys and heart, so as for the ophthalmologist any vascular change in the retina can signalize a systemic disease (diabetes mellitus, stroke, arterial hypertension) that is more or less symptomatic for the patient. The purpose of this meta-analysis was to reviview recent literature data related to the connections between different hemodynamic structures and their impact on the retinal blood flow.

  5. Bromovinyldeoxyurdine treatment of outer retinal necrosis due to varicella-zoster virus: a case-report.

    PubMed

    Dullaert, H; Maudgal, P C; Leys, A; Dralands, L; Clercq, E

    1996-01-01

    In December 1995, a 70-years old male was referred to us because of rapid visual loss in the right eye, one month after a central retinal artery occlusion in the left eye. This renal transplant patient, with limited renal function, was on immunosuppressive therapy. The diagnosis of bilateral progressive outer retinal necrosis (PORN) due to varicella-zoster virus (VZV) was confirmed by polymerase chain reaction (PCR) detection of VZV DNA in the aqueous fluid. As retinitis progressed despite of intravenous acyclovir administration, the antiviral therapy was switched to oral bromovinyldeoxyuridine (BVDU). This case-report demonstrates that oral BVDU can be a good alternative to acyclovir for the treatment of VZV retinal infections.

  6. Simple eye-hand reaction time in the retinal periphery can be reduced with training.

    PubMed

    Ciuffreda, Kenneth J

    2011-05-01

    One critical aspect of sports vision is eye-hand reaction time, especially for visual stimuli in the retinal periphery. A key question is, "Can eye-hand reaction time be reduced with training?" Evidence from a series of recent experiments suggests that it can. The results in the retinal periphery demonstrated the following: (1) eye-hand reaction time can be reduced by training a small extent (∼10-20 msec) involving central visual processing changes, (2) the training effect transfers to other retinal loci, and (3) the improvement is retained following the cessation of training. These results suggest that training of eye-hand reaction time in the retinal periphery should be considered in athletes to potentially improve their on-field sports performance.

  7. Retinal nerve fiber layer thickness and visual hallucinations in Parkinson's Disease.

    PubMed

    Lee, Jee-Young; Kim, Jae Min; Ahn, Jeeyun; Kim, Han-Joon; Jeon, Beom S; Kim, Tae Wan

    2014-01-01

    Defective visual information processing from both central and peripheral pathways is one of the suggested mechanisms of visual hallucination in Parkinson's disease (PD). To investigate the role of retinal thinning for visual hallucination in PD, we conducted a case-control study using spectral domain optical coherence tomography. We examined a representative sample of 61 patients with PD and 30 healthy controls who had no history of ophthalmic diseases. General ophthalmologic examinations and optical coherence tomography scans were performed in each participant. Total macular thickness and the thickness of each retinal layer on horizontal scans through the fovea were compared between the groups. In a comparison between patients with PD and healthy controls, there was significant parafoveal inner nuclear layer thinning, whereas other retinal layers, including the retinal nerve fiber layer, as well as total macular thicknesses were not different. In terms of visual hallucinations among the PD subgroups, only retinal nerve fiber layer thickness differed significantly, whereas total macular thickness and the thickness of other retinal layers did not differ. The retinal nerve fiber layer was thinnest in the group that had hallucinations without dementia, followed by the group that had hallucinations with dementia, and the group that had no hallucinations and no dementia. General ophthalmologic examinations did not reveal any significant correlation with hallucinations. There were no significant correlations between retinal thicknesses and duration or severity of PD and medication dosages. The results indicate that retinal nerve fiber layer thinning may be related to visual hallucination in nondemented patients with PD. Replication studies as well as further studies to elucidate the mechanism of thinning are warranted.

  8. Randomized trial of radiation-free central nervous system prophylaxis comparing intrathecal triple therapy with liposomal cytarabine in acute lymphoblastic leukemia

    PubMed Central

    Bassan, Renato; Masciulli, Arianna; Intermesoli, Tamara; Audisio, Ernesta; Rossi, Giuseppe; Pogliani, Enrico Maria; Cassibba, Vincenzo; Mattei, Daniele; Romani, Claudio; Cortelezzi, Agostino; Corti, Consuelo; Scattolin, Anna Maria; Spinelli, Orietta; Tosi, Manuela; Parolini, Margherita; Marmont, Filippo; Borlenghi, Erika; Fumagalli, Monica; Cortelazzo, Sergio; Gallamini, Andrea; Marfisi, Rosa Maria; Oldani, Elena; Rambaldi, Alessandro

    2015-01-01

    Developing optimal radiation-free central nervous system prophylaxis is a desirable goal in acute lymphoblastic leukemia, to avoid the long-term toxicity associated with cranial irradiation. In a randomized, phase II trial enrolling 145 adult patients, we compared intrathecal liposomal cytarabine (50 mg: 6/8 injections in B-/T-cell subsets, respectively) with intrathecal triple therapy (methotrexate/cytarabine/prednisone: 12 injections). Systemic therapy included methotrexate plus cytarabine or L-asparaginase courses, with methotrexate augmented to 2.5 and 5 g/m2 in Philadelphia-negative B- and T-cell disease, respectively. The primary study objective was the comparative assessment of the risk/benefit ratio, combining the analysis of feasibility, toxicity and efficacy. In the liposomal cytarabine arm 17/71 patients (24%) developed grade 3–4 neurotoxicity compared to 2/74 (3%) in the triple therapy arm (P=0.0002), the median number of episodes of neurotoxicity of any grade was one per patient compared to zero, respectively (P=0.0001), and even though no permanent disabilities or deaths were registered, four patients (6%) discontinued intrathecal prophylaxis on account of these toxic side effects (P=0.06). Neurotoxicity worsened with liposomal cytarabine every 14 days (T-cell disease), and was improved by the adjunct of intrathecal dexamethasone. Two patients in the liposomal cytarabine arm suffered from a meningeal relapse (none with T-cell disease, only one after high-dose chemotherapy) compared to four in the triple therapy arm (1 with T-cell disease). While intrathecal liposomal cytarabine could contribute to improved, radiation-free central nervous system prophylaxis, the toxicity reported in this trial does not support its use at 50 mg and prompts the investigation of a lower dosage. (clinicaltrials.gov identifier: NCT-00795756). PMID:25749825

  9. Retinal vessels caliber changes after strabismus surgery: results of 6mo follow-up

    PubMed Central

    Li, Ji-Peng; Fu, Jing; Zhou, Jin-Qiong; Wang, Xiao-Zhen; Wang, Wen-Ying; Liu, Ning-Pu

    2016-01-01

    AIM To evaluate the effect of strabismus surgery on retinal vessels calibers with digital color fundus photographs. METHODS Two hundred consecutive strabismus patients underwent surgery, and 118 patients (female/male, 55/63) who finished 6-month follow-up were finally included in this study. Optic disc-centered digital color fundus photographs of both eyes of all patients were taken prior to surgery and 6mo post surgery. The retinal vascular caliber of 116 operated eyes were measured using the computer program IVAN. The operated eyes were divided into 3 groups according to the surgical methods, recession of one muscle, one muscle recession and one muscle folding, one muscle resection and one muscle recession. The effect of number of altered muscles on retinal vessels was analyzed using statistic software SPSS 16.0. RESULTS The mean age was 12.4±8.6y. Averaged central retinal artery equivalent (CRAE) of all patients was 120.31±23.02 µm preoperatively, and 122.87±15.93 µm six months after surgery. Averaged central retinal vein equivalent (CRVE) was 171.11±31.73 µm preoperatively and 175.02±21.00 µm postoperatively. There was no significant difference of averaged CRAE (P=0.22) or CRVE (P=0.19) before and after operation. Averaged arteriole to venule ratio (AVR) was 0.71±0.07 before surgery and 0.70±0.07 after surgery. Comparison of preoperative and postoperative retinal vessels calibers among different surgical groups did not show significant differences. Also, there was no advantage of rectus muscle folding to muscle resection. CONCLUSION Up to 6mo after strabismus surgery, the retinal vascular calibers were not altered. No more than two muscles in one surgery are safe for retinal perfusion.

  10. Retinal vessels caliber changes after strabismus surgery: results of 6mo follow-up

    PubMed Central

    Li, Ji-Peng; Fu, Jing; Zhou, Jin-Qiong; Wang, Xiao-Zhen; Wang, Wen-Ying; Liu, Ning-Pu

    2016-01-01

    AIM To evaluate the effect of strabismus surgery on retinal vessels calibers with digital color fundus photographs. METHODS Two hundred consecutive strabismus patients underwent surgery, and 118 patients (female/male, 55/63) who finished 6-month follow-up were finally included in this study. Optic disc-centered digital color fundus photographs of both eyes of all patients were taken prior to surgery and 6mo post surgery. The retinal vascular caliber of 116 operated eyes were measured using the computer program IVAN. The operated eyes were divided into 3 groups according to the surgical methods, recession of one muscle, one muscle recession and one muscle folding, one muscle resection and one muscle recession. The effect of number of altered muscles on retinal vessels was analyzed using statistic software SPSS 16.0. RESULTS The mean age was 12.4±8.6y. Averaged central retinal artery equivalent (CRAE) of all patients was 120.31±23.02 µm preoperatively, and 122.87±15.93 µm six months after surgery. Averaged central retinal vein equivalent (CRVE) was 171.11±31.73 µm preoperatively and 175.02±21.00 µm postoperatively. There was no significant difference of averaged CRAE (P=0.22) or CRVE (P=0.19) before and after operation. Averaged arteriole to venule ratio (AVR) was 0.71±0.07 before surgery and 0.70±0.07 after surgery. Comparison of preoperative and postoperative retinal vessels calibers among different surgical groups did not show significant differences. Also, there was no advantage of rectus muscle folding to muscle resection. CONCLUSION Up to 6mo after strabismus surgery, the retinal vascular calibers were not altered. No more than two muscles in one surgery are safe for retinal perfusion. PMID:27672600

  11. Prospects of Stem Cells for Retinal Diseases.

    PubMed

    Ng, Tsz Kin; Lam, Dennis S C; Cheung, Herman S

    2013-01-01

    Retinal diseases, including glaucoma, retinitis pigmentosa, diabetic retinopathy, and age-related macular degeneration, are the leading causes of irreversible visual impairment and blindness in developed countries. Traditional and current treatment regimens are based on surgical or medical interventions to slow down the disease progression. However, the number of retinal cells would continue to diminish, and the diseases could not be completely cured. There is an emerging role of stem cells in retinal research. The stem cell therapy on retinal diseases is based on 2 theories: cell replacement therapy and neuroprotective effect. The former hypothesizes that new retinal cells could be regenerated from stem cells to substitute the damaged cells in the diseased retina, whereas the latter believes that the paracrine effects of stem cells modulate the microenvironments of the diseased retina so as to protect the retinal neurons. This article summarizes the choice of stem cells in retinal research. Moreover, the current progress of retinal research on stem cells and the clinical applications of stem cells on retinal diseases are reviewed. In addition, potential challenges and future prospects of retinal stem cell research are discussed.

  12. [Progress of research in retinal image registration].

    PubMed

    Yu, Lun; Wei, Lifang; Pan, Lin

    2011-10-01

    The retinal image registration has important applications in the processes of auxiliary diagnosis and treatment for a variety of diseases. The retinal image registration can be used to measure the disease process and the therapeutic effect. A variety of retinal image registration techniques have been studied extensively in recent years. However, there are still many problems existing and there are numerous research possibilities. Based on extensive investigation of existing literatures, the present paper analyzes the feature of retinal image and current challenges of retinal image registration, and reviews the transformation models of the retinal image registration technology and the main research algorithms in current retinal image registration, and analyzes the advantages and disadvantages of various types of algorithms. Some research challenges and future developing trends are also discussed.

  13. Retinal Regeneration is Facilitated by the Presence of Surviving Neurons

    PubMed Central

    Sherpa, Tshering; Lankford, Tyler; McGinn, Tim E.; Hunter, Samuel S.; Frey, Ruth A.; Sun, Chi; Ryan, Mariel; Robison, Barrie D.; Stenkamp, Deborah L.

    2014-01-01

    Teleost fish regenerate their retinas after damage, in contrast to mammals. In zebrafish subjected to an extensive ouabain-induced lesion that destroys all neurons and spares Müller glia, functional recovery and restoration of normal optic nerve head (ONH) diameter take place at 100 days post-injury. Subsequently, regenerated retinas overproduce cells in the retinal ganglion cell (RGC) layer, and the ONH becomes enlarged. Here we test the hypothesis that a selective injury, which spares photoreceptors and Müller glia, results in faster functional recovery and fewer long-term histological abnormalities. Following this selective retinal damage, recovery of visual function required 60 days, consistent with this hypothesis. In contrast to extensively damaged retinas, selectively damaged retinas showed fewer histological errors and did not overproduce neurons. Extensively damaged retinas had RGC axons that were delayed in pathfinding to the ONH, and showed misrouted axons within the ONH, suggesting that delayed functional recovery following an extensive lesion is related to defects in RGC axons exiting the eye and/or reaching their central targets. The atoh7, fgf8a, shha, and netrin-1 genes were differentially expressed, and the distribution of Hh protein was disrupted following extensive damage as compared with selective damage. Confirming a role for Shh signaling in supporting rapid regeneration, shhat4+/− zebrafish showed delayed functional recovery following selective damage. We suggest that surviving retinal neurons provide structural/molecular information to regenerating neurons, and that this patterning mechanism regulates factors such as Shh. These factors in turn control neuronal number, retinal lamination, and RGC axon pathfinding during retinal regeneration. PMID:24488694

  14. Retinal Remodeling and Metabolic Alterations in Human AMD

    PubMed Central

    Jones, Bryan W.; Pfeiffer, Rebecca L.; Ferrell, William D.; Watt, Carl B.; Tucker, James; Marc, Robert E.

    2016-01-01

    Age-related macular degeneration (AMD) is a progressive retinal degeneration resulting in central visual field loss, ultimately causing debilitating blindness. AMD affects 18% of Americans from 65 to 74, 30% older than 74 years of age and is the leading cause of severe vision loss and blindness in Western populations. While many genetic and environmental risk factors are known for AMD, we currently know less about the mechanisms mediating disease progression. The pathways and mechanisms through which genetic and non-genetic risk factors modulate development of AMD pathogenesis remain largely unexplored. Moreover, current treatment for AMD is palliative and limited to wet/exudative forms. Retina is a complex, heterocellular tissue and most retinal cell classes are impacted or altered in AMD. Defining disease and stage-specific cytoarchitectural and metabolic responses in AMD is critical for highlighting targets for intervention. The goal of this article is to illustrate cell types impacted in AMD and demonstrate the implications of those changes, likely beginning in the retinal pigment epithelium (RPE), for remodeling of the the neural retina. Tracking heterocellular responses in disease progression is best achieved with computational molecular phenotyping (CMP), a tool that enables acquisition of a small molecule fingerprint for every cell in the retina. CMP uncovered critical cellular and molecular pathologies (remodeling and reprogramming) in progressive retinal degenerations such as retinitis pigmentosa (RP). We now applied these approaches to normal human and AMD tissues mapping progression of cellular and molecular changes in AMD retinas, including late-stage forms of the disease. PMID:27199657

  15. Retinitis Pigmentosa and Education Issues

    ERIC Educational Resources Information Center

    Brown, Thomas J.

    2005-01-01

    Retinitis Pigmentosa includes a number of inherited diseases which usually result in blindness. The disease is progressive in nature and begins with the deterioration of cells in the eye responsible for peripheral vision. As the condition worsens there is a gradual loss of peripheral vision and night blindness. Proper educational planning requires…

  16. Automatic temperature controlled retinal photocoagulation

    NASA Astrophysics Data System (ADS)

    Schlott, Kerstin; Koinzer, Stefan; Ptaszynski, Lars; Bever, Marco; Baade, Alex; Roider, Johann; Birngruber, Reginald; Brinkmann, Ralf

    2012-06-01

    Laser coagulation is a treatment method for many retinal diseases. Due to variations in fundus pigmentation and light scattering inside the eye globe, different lesion strengths are often achieved. The aim of this work is to realize an automatic feedback algorithm to generate desired lesion strengths by controlling the retinal temperature increase with the irradiation time. Optoacoustics afford non-invasive retinal temperature monitoring during laser treatment. A 75 ns/523 nm Q-switched Nd:YLF laser was used to excite the temperature-dependent pressure amplitudes, which were detected at the cornea by an ultrasonic transducer embedded in a contact lens. A 532 nm continuous wave Nd:YAG laser served for photocoagulation. The ED50 temperatures, for which the probability of ophthalmoscopically visible lesions after one hour in vivo in rabbits was 50%, varied from 63°C for 20 ms to 49°C for 400 ms. Arrhenius parameters were extracted as ΔE=273 J mol-1 and A=3.1044 s-1. Control algorithms for mild and strong lesions were developed, which led to average lesion diameters of 162+/-34 μm and 189+/-34 μm, respectively. It could be demonstrated that the sizes of the automatically controlled lesions were widely independent of the treatment laser power and the retinal pigmentation.

  17. High frequency of central memory regulatory T cells allows detection of liver recipients at risk of early acute rejection within the first month after transplantation.

    PubMed

    Boix-Giner, Francisco; Millan, Olga; San Segundo, David; Muñoz-Cacho, Pedro; Mancebo, Esther; Llorente, Santiago; Rafael-Valdivia, Lourdes; Rimola, Antoni; Fábrega, Emilio; Mrowiec, Anna; Allende, Luis; Minguela, Alfredo; Bolarín, Jose M; Paz-Artal, Estela; López-Hoyos, Marcos; Brunet, Mercé; Muro, Manuel

    2016-02-01

    Several studies have analyzed the potential of T regulatory cells (Treg cells) as biomarkers of acute rejection (AR). The aim of the present multicenter study was to correlate the percentage of peripheral Treg cells in liver graft recipients drawn at baseline up to 12 months after transplantation with the presence of AR. The percentage of central memory (cm) Treg cells (CD4(+)CD25(high)CD45RO(+)CD62L(+)) was monitored at pre-transplant and at 1 and 2 weeks, and 1, 2, 3 and 6 months and 1 year post-transplantation. The same validation standard operating procedures were used in all participating centers. Fifteen patients developed AR (23.4%). Hepatitis C virus recurrence was observed in 16 recipients, who displayed low peripheral blood cmTreg levels compared with patients who did not. A steady increase of cmTregs was observed during the first month after transplantation with statistically significant differences between AR and non-AR patients. The high frequency of memory Treg cells allowed us to monitor rejection episodes during the first month post-transplantation. On the basis of these data, we developed a prediction model for assessing risk of AR that can provide clinicians with useful information for managing patients individually and customizing immunosuppressive therapies.

  18. An animal model to study toxicity of central nervous system therapy for childhood acute lymphoblastic leukemia: Effects on growth and craniofacial proportion

    SciTech Connect

    Schunior, A.; Zengel, A.E.; Mullenix, P.J.; Tarbell, N.J.; Howes, A.; Tassinari, M.S. )

    1990-10-15

    Many long term survivors of childhood acute lymphoblastic leukemia have short stature, as well as craniofacial and dental abnormalities, as side effects of central nervous system prophylactic therapy. An animal model is presented to assess these adverse effects on growth. Cranial irradiation (1000 cGy) with and without prednisolone (18 mg/kg i.p.) and methotrexate (2 mg/kg i.p.) was administered to 17- and 18-day-old Sprague-Dawley male and female rats. Animals were weighed 3 times/week. Final body weight and body length were measured at 150 days of age. Femur length and craniofacial dimensions were measured directly from the bones, using calipers. For all exposed groups there was a permanent suppression of weight gain with no catch-up growth or normal adolescent growth spurt. Body length was reduced for all treated groups, as were the ratios of body weight to body length and cranial length to body length. Animals subjected to cranial irradiation exhibited microcephaly, whereas those who received a combination of radiation and chemotherapy demonstrated altered craniofacial proportions in addition to microcephaly. Changes in growth patterns and skeletal proportions exhibited sexually dimorphic characteristics. The results indicate that cranial irradiation is a major factor in the growth failure in exposed rats, but chemotherapeutic agents contribute significantly to the outcome of growth and craniofacial dimensions.

  19. Detection of localized retinal malfunction in retinal degeneration model using a multielectrode array system.

    PubMed

    Homma, Kohei; Osakada, Fumitaka; Hirami, Yasuhiko; Jin, Zi-Bing; Mandai, Michiko; Takahashi, Masayo

    2009-07-01

    Light stimulation inhibits the retinal dark current through phototransduction signals in the photoreceptors. Electroretinography (ERG) detects the blockage of the dark current as the a-wave of the ERG. However, standard ERGs represent the summed neural activity of the retina, and information on localized functions cannot be obtained. In this study, we used a multielectrode array (MEA) system and directly recorded the focal activities of the photoreceptors of the retina. Retinas were isolated from dark-adapted rodents and were draped over the electrode array with vitreal surface of the retina on the electrode array. After light stimulation, negative waves were recorded from each electrode. Adding aminobutyric acid, a selective agonist of mGluR6 expressed on ON-bipolar cells, to the media did not block the generation of the responses. The amplitude of the response increased with increasing retinal development. When the retina was locally injured, light-elicited responses were diminished only in the injured areas of the retina. Retinas isolated from rats given N-methyl-N-nitrosourea (MNU) were also tested. In central retinas of MNU-treated rats, the responses were progressively decreased following injection of MNU. In contrast, in the peripheral retinas, amplitude of the responses was relatively retained, consistent with the retinal thickness observed by immunohistochemistry. In conclusion, light-evoked responses were recorded with the MEA system. The MEA system was useful for detecting subtle and focal activation of photoreceptors. This spatial information should be valuable in investigating local functional recovery in therapeutically treated areas, such as in gene transfer or cell transplantation. PMID:19224574

  20. Ultra-widefield fluorescein angiography reveals retinal phlebitis in Susac's syndrome.

    PubMed

    Klufas, Michael A; Dinkin, Marc J; Bhaleeya, Swetangi D; Chapman, Kristin O; Riley, Claire S; Kiss, Szilárd

    2014-01-01

    A 23-year-old woman with history of headaches and auditory changes presented with acute-onset visual field loss in the right eye. The combination of multiple retinal branch artery occlusions of the right eye on funduscopic examination, characteristic white matter lesions in the corpus callosum on magnetic resonance imaging, and hearing loss on audiometric testing led to a diagnosis of Susac's syndrome. Ultra-widefield fluorescein angiography revealed involvement of the retinal veins, which has not been previously reported with this condition. Additionally, ultra-widefield indocyanine green angiography demonstrated changes in the choroidal circulation, which are controversial in this syndrome. PMID:24972181

  1. Change of retinal nerve fiber layer thickness in patients with nonarteritic inflammatory anterior ischemic optic neuropathy.

    PubMed

    Liu, Tingting; Bi, Hongsheng; Wang, Xingrong; Wang, Guimin; Li, Haiyan; Wu, Hui; Qu, Yi; Wen, Ying; Cong, Chenyang; Wang, Daoguang

    2012-12-15

    In this study, 16 patients (19 eyes) with nonarteritic anterior ischemic optic neuropathy in the acute stage (within 4 weeks) and resolving stage (after 12 weeks) were diagnosed by a series of complete ophthalmic examinations, including fundus examination, optical coherence tomography and fluorescein fundus angiography, and visual field defects were measured with standard automated perimetry. The contralateral uninvolved eyes were used as controls. The retinal nerve fiber layer thickness was determined by optical coherence tomography which showed that the mean retinal nerve fiber layer thickness and the retinal nerve fiber layer thickness from temporal, superior, nasal and inferior quadrants were significantly higher for all measurements in the acute stage than the corresponding normal values. In comparison, the retinal nerve fiber layer thickness from each optic disc quadrant was found to be significantly lower when measured at the resolving stages, than in the control group. Statistical analysis on the correlation between optic disc nerve fiber layer thickness and visual defects demonstrated a positive correlation in the acute stage and a negative correlation in the resolving stage. Our experimental findings indicate that optical coherence tomography is a useful diagnostic method for nonarteritic anterior ischemic optic neuropathy and can be used to evaluate the effect of treatment.

  2. Comparison of Common Retinal Vessel Caliber Measurement Software and a Conversion Algorithm

    PubMed Central

    Yip, WanFen; Tham, Yih Chung; Hsu, Wynne; Lee, Mong Li; Klein, Ronald; Klein, Barbara; Ikram, Mohammad Kamran; Wong, Tien Yin; Cheung, Carol Yim-lui

    2016-01-01

    Purpose To compare three commonly used retinal vessel caliber measurement software systems, and propose an algorithm for conversion between measurement systems. Methods We used 120 retinal photographs to evaluate the agreement between three commonly used software (Retinal Analysis [RA], Integrative Vessel Analysis [IVAN], and Singapore I Vessel Assessment [SIVA]). Bland-Altman plots were used to evaluate agreement of retinal arteriolar (central retinal artery equivalent, CRAE) and venular (central retinal vein equivalent, CRVE) calibers. Pearson's correlation was used to assess the associations between systemic factors and retinal vessel calibers, and Z-test was used to compare the strength of the correlation coefficients across the three software systems. An algorithm was created to convert measurements, with paired t-test performed to evaluate the differences between SIVA-measured retinal calibers and SIVA-approximates converted from RA- and IVAN-measurements using the algorithm. Results Differences between SIVA- and RA-measured calibers (CRAE: mean difference [MD] = −21.8 μm, 95% limits of agreement [LOA], −47.3 to 3.7 μm; CRVE: MD = −7.7 μm, 95% LOA, −28.0 to 12.6 μm), SIVA- and IVAN-measured calibers (CRAE: MD = −6.7 μm, 95% LOA, −23.8 to 10.4 μm; CRVE: MD = −18.2 μm 95% LOA, −36.7 to 0.4 μm) were large. However, the strength of correlations between systemic factors with SIVA-measured retinal calibers was not significantly different to that measured using RA and IVAN (P ≥ 0.332). SIVA-approximates converted from RA and IVAN measurements using the proposed algorithm was not significantly different from SIVA-measured calibers (P ≥ 0.20). Conclusion Absolute measurements of retinal vessel calibers vary between three common software systems but associations with systemic factors were similar. Translational Relevance The proposed algorithm allowed conversions of RA and IVAN measurements to SIVA-approximates. This conversion is important

  3. A Pilot Study of Fourier Domain Optical Coherence Tomography of Retinal Dystrophy Patients

    PubMed Central

    Lim, Jennifer I.; Tan, Ou; Fawzi, Amani A.; Hopkins, J. Jill; Gil-Flamer, John H.; Huang, David

    2009-01-01

    Purpose To characterize the macular anatomy of retinal dystrophy eyes using high-speed, high-resolution, Fourier-domain optical coherence tomography (FD-OCT). Design Case control study. Methods Patients with retinal dystrophy and normal age and gender matched controls underwent FD-OCT imaging using the RTVue™ (Optovue, Inc.), which has an axial resolution of 5 microns. Vertical and horizontal eight mm scans of 1,024 lines/cross-section were obtained. Based on boundaries manually drawn on computer displays of OCT cross-sections, the thicknesses of the retina, inner retinal layer (IRL) and outer retinal layer (ORL) were averaged over both 5 and 1.5 millimeters regions centered at the fovea. The inner retina layer (IRL) was the sum of nerve fiber layer (NFL), ganglion cell layer (GCL) and inner plexiform layer (IPL) thicknesses. Total retinal thickness (RT) was measured between the inner edges of the NFL and the retinal pigment epithelium. Outer retinal layer (ORL) thickness was calculated by subtracting IRL thickness from RT. Results 14 patients (7 retinal dystrophy patients and seven normal controls) underwent high resolution OCT imaging. Patients ranged in age from 33 to 84 years old. Retinal dystrophy diagnoses included retinitis pigmentosa (3), cone-rod degeneration (2), and Stargardt disease (2). The following thickness values reported are mean ± standard deviation. Mean foveal RT (foveal RT) averaged over a 1.5 mm area was 271.3+/-23.3μ for normal patients and 159.2+/-48.0 μ for dystrophy (p<0.001) patients. Mean macular RT (macular RT), averaged over the central 5-mm area, was 292.8+/-8.1 μ for normal patients and 199.1+/-32.7μ for dystrophy patients (p<0.001). Mean macular IRL was 109.9 ± 6.4 for normals and 98.0 +/-20.6μ for dystrophy patients (p=0.02); mean macular ORL was 182.9+/-4.7 μ for normals and 101.1+/-18.8μ for dystrophy patients (p<0.001). Conclusion Eyes with retinal dystrophy had a small (11%) decrease in macular IRL and severe (45

  4. Two-Step Reactivation of Dormant Cones in Retinitis Pigmentosa

    PubMed Central

    Wang, Wei; Lee, Sang Joon; Scott, Patrick A.; Lu, Xiaoqin; Emery, Douglas; Liu, Yongqin; Ezashi, Toshihiko; Roberts, Michael R.; Ross, Jason W.; Kaplan, Henry J.; Dean, Douglas C.

    2016-01-01

    Most Retinitis Pigmentosa (RP) mutations arise in rod photoreceptor genes, leading to diminished peripheral and nightime vision. Using a pig model of autosomal-dominant RP, we show glucose becomes sequestered in the retinal pigment epithelium (RPE), and thus is not transported to photoreceptors. The resulting starvation for glucose metabolites impairs synthesis of cone visual pigment -rich outer segments (OS), and then their mitochondrial-rich inner segments dissociate. Loss of these functional structures diminishes cone-dependent high-resolution central vision, which is utilized for most daily tasks. By transplanting wild-type rods, to restore glucose transport, or directly replacing glucose in the subretinal space, to bypass its retention in the RPE, we can regenerate cone functional structures, reactivating the dormant cells. Beyond providing metabolic building blocks for cone functional structures, we show glucose induces thioredoxin-interacting protein (Txnip) to regulate Akt signaling, thereby shunting metabolites toward aerobic glucose metabolism and regenerating cone OS synthesis. PMID:27050517

  5. Two-Step Reactivation of Dormant Cones in Retinitis Pigmentosa.

    PubMed

    Wang, Wei; Lee, Sang Joon; Scott, Patrick A; Lu, Xiaoqin; Emery, Douglas; Liu, Yongqin; Ezashi, Toshihiko; Roberts, Michael R; Ross, Jason W; Kaplan, Henry J; Dean, Douglas C

    2016-04-12

    Most retinitis pigmentosa (RP) mutations arise in rod photoreceptor genes, leading to diminished peripheral and nighttime vision. Using a pig model of autosomal-dominant RP, we show glucose becomes sequestered in the retinal pigment epithelium (RPE) and, thus, is not transported to photoreceptors. The resulting starvation for glucose metabolites impairs synthesis of cone visual pigment-rich outer segments (OSs), and then their mitochondrial-rich inner segments dissociate. Loss of these functional structures diminishes cone-dependent high-resolution central vision, which is utilized for most daily tasks. By transplanting wild-type rods, to restore glucose transport, or directly replacing glucose in the subretinal space, to bypass its retention in the RPE, we can regenerate cone functional structures, reactivating the dormant cells. Beyond providing metabolic building blocks for cone functional structures, we show glucose induces thioredoxin-interacting protein (Txnip) to regulate Akt signaling, thereby shunting metabolites toward aerobic glucose metabolism and regenerating cone OS synthesis. PMID:27050517

  6. A rare case of branch retinal vein occlusion following Sirsasana

    PubMed Central

    Balamurugan, Anugraha; Srikanth, Krishnagopal

    2016-01-01

    Sirsasana is a type of headstand postural yoga in which the body is completely inverted. It is performed with or without wall support. In this position, the body is held upright supported by the forearms, while the crown of the head rests lightly on the floor. This is an advanced pose and should be attempted under the supervision of a qualified yoga instructor. The practice of Sirsasana is postulated to increase blood flow to the brain, improving memory, and other intellectual functions. It is also known to cause causes raised intraocular pressure, decompression retinopathy, glaucomatous visual field defects, central retinal vein occlusion, progression of glaucoma, optic neuropathy, and conjunctival varix thrombosis. We report a case of branch retinal vein occlusion following Sirsasana in a patient with systemic hypertension. PMID:27512326

  7. [Morphologic aspects of therapy-resistant cytomegalovirus retinitis].

    PubMed

    Meyer, P; Bernauer, W; Daicker, B; Zimmerli, W; Rüttimann, S

    1992-05-01

    Intravenous ganciclovir treatment was performed in eight male AIDS patients with primary unilateral CMV-retinitis. Three patients developed slowly progressive CMV-retinitis in the fellow eye despite adequate dose of ganciclovir. These different CMV-manifestations are shown in a sequence of fundus pictures. Three types of CMV-lesions were observed in connection with this study. Untreated central lesions showed the aspect of crumbled cheese and ketchup. Untreated lesions in the peripherie were yellowish-white, granular, "dry" and showed in most cases no haemorrhages. Lesions appearing during treatment showed initially "dry" white opaque subretinal areas, turning later on to the typical aspect of untreated lesions. The progression could not be stopped by highdose ganciclovir i.v. and thus bilateral blindness resulted after 12 to 22 months. The level of CD4-lymphocytes in the blood was diminished in all patients, but much more in patients with progressive disease. PMID:1319528

  8. A rare case of branch retinal vein occlusion following Sirsasana.

    PubMed

    Balamurugan, Anugraha; Srikanth, Krishnagopal

    2016-01-01

    Sirsasana is a type of headstand postural yoga in which the body is completely inverted. It is performed with or without wall support. In this position, the body is held upright supported by the forearms, while the crown of the head rests lightly on the floor. This is an advanced pose and should be attempted under the supervision of a qualified yoga instructor. The practice of Sirsasana is postulated to increase blood flow to the brain, improving memory, and other intellectual functions. It is also known to cause causes raised intraocular pressure, decompression retinopathy, glaucomatous visual field defects, central retinal vein occlusion, progression of glaucoma, optic neuropathy, and conjunctival varix thrombosis. We report a case of branch retinal vein occlusion following Sirsasana in a patient with systemic hypertension. PMID:27512326

  9. Vaccination for protection of retinal ganglion cells against death from glutamate cytotoxicity and ocular hypertension: Implications for glaucoma

    NASA Astrophysics Data System (ADS)

    Schori, Hadas; Kipnis, Jonathan; Yoles, Eti; Woldemussie, Elizabeth; Ruiz, Guadalupe; Wheeler, Larry A.; Schwartz, Michal

    2001-03-01

    Our group recently demonstrated that autoimmune T cells directed against central nervous system-associated myelin antigens protect neurons from secondary degeneration. We further showed that the synthetic peptide copolymer 1 (Cop-1), known to suppress experimental autoimmune encephalomyelitis, can be safely substituted for the natural myelin antigen in both passive and active immunization for neuroprotection of the injured optic nerve. Here we attempted to determine whether similar immunizations are protective from retinal ganglion cell loss resulting from a direct biochemical insult caused, for example, by glutamate (a major mediator of degeneration in acute and chronic optic nerve insults) and in a rat model of ocular hypertension. Passive immunization with T cells reactive to myelin basic protein or active immunization with myelin oligodendrocyte glycoprotein-derived peptide, although neuroprotective after optic nerve injury, was ineffective against glutamate toxicity in mice and rats. In contrast, the number of surviving retinal ganglion cells per square millimeter in glutamate-injected retinas was significantly larger in mice immunized 10 days previously with Cop-1 emulsified in complete Freund's adjuvant than in mice injected with PBS in the same adjuvant (2,133 ± 270 and 1,329 ± 121, respectively, mean ± SEM; P < 0.02). A similar pattern was observed when mice were immunized on the day of glutamate injection (1,777 ± 101 compared with 1,414 ± 36; P <0.05), but not when they were immunized 48h later. These findings suggest that protection from glutamate toxicity requires reinforcement of the immune system by antigens that are different from those associated with myelin. The use of Cop-1 apparently circumvents this antigen specificity barrier. In the rat ocular hypertension model, which simulates glaucoma, immunization with Cop-1 significantly reduced the retinal ganglion cell loss from 27.8%±6.8% to 4.3%±1.6%, without affecting the intraocular pressure

  10. Retinal vasculature classification using novel multifractal features

    NASA Astrophysics Data System (ADS)

    Ding, Y.; Ward, W. O. C.; Duan, Jinming; Auer, D. P.; Gowland, Penny; Bai, L.

    2015-11-01

    Retinal blood vessels have been implicated in a large number of diseases including diabetic retinopathy and cardiovascular diseases, which cause damages to retinal blood vessels. The availability of retinal vessel imaging provides an excellent opportunity for monitoring and diagnosis of retinal diseases, and automatic analysis of retinal vessels will help with the processes. However, state of the art vascular analysis methods such as counting the number of branches or measuring the curvature and diameter of individual vessels are unsuitable for the microvasculature. There has been published research using fractal analysis to calculate fractal dimensions of retinal blood vessels, but so far there has been no systematic research extracting discriminant features from retinal vessels for classifications. This paper introduces new methods for feature extraction from multifractal spectra of retinal vessels for classification. Two publicly available retinal vascular image databases are used for the experiments, and the proposed methods have produced accuracies of 85.5% and 77% for classification of healthy and diabetic retinal vasculatures. Experiments show that classification with multiple fractal features produces better rates compared with methods using a single fractal dimension value. In addition to this, experiments also show that classification accuracy can be affected by the accuracy of vessel segmentation algorithms.

  11. Pharmacologic vitreolysis with ocriplasmin: rationale for use and therapeutic potential in vitreo-retinal disorders.

    PubMed

    Khoshnevis, Matin; Sebag, J

    2015-04-01

    With increased knowledge about the origins and pathophysiology of vitreo-retinal disorders—and, in particular, the central role of anomalous posterior vitreous detachment in vitreo-maculopathies—a paradigm shift from surgery to pharmacotherapy is taking place with the development of pharmacologic vitreolysis. The first approved agent for pharmacologic vitreolysis therapy is ocriplasmin, a truncated form of the nonspecific serine protease plasmin. Twelve studies comprise the current ocriplasmin clinical trial program, demonstrating the efficacy and safety of a single intravitreal injection of ocriplasmin for the treatment of patients with symptomatic vitreo-macular adhesion or vitreo-macular traction, including patients with macular holes. Although post-approval implementation of ocriplamsin in clinical practice has shown success rates of up to 78%, there have been recent case reports of acute, transient visual dysfunction. There are thus new initiatives to further refine clinical indications for case selection and to identify possible untoward effects. Although more studies are warranted, it appears that ocriplasmin offers a good alternative to surgery. The future lies in pharmacologic vitreolysis, and the future of pharmacologic vitreolysis lies in prevention. Thus, long-term studies are needed to define a role for pharmacologic vitreolysis, in particular with ocriplasmin, in the prevention of progressive diabetic retinopathy and age-related macular degeneration. PMID:25812991

  12. Air Pollution and the Microvasculature: A Cross-Sectional Assessment of In Vivo Retinal Images in the Population-Based Multi-Ethnic Study of Atherosclerosis (MESA)

    PubMed Central

    Adar, Sara D.; Klein, Ronald; Klein, Barbara E. K.; Szpiro, Adam A.; Cotch, Mary Frances; Wong, Tien Y.; O'Neill, Marie S.; Shrager, Sandi; Barr, R. Graham; Siscovick, David S.; Daviglus, Martha L.; Sampson, Paul D.; Kaufman, Joel D.

    2010-01-01

    Background Long- and short-term exposures to air pollution, especially fine particulate matter (PM2.5), have been linked to cardiovascular morbidity and mortality. One hypothesized mechanism for these associations involves microvascular effects. Retinal photography provides a novel, in vivo approach to examine the association of air pollution with changes in the human microvasculature. Methods and Findings Chronic and acute associations between residential air pollution concentrations and retinal vessel diameters, expressed as central retinal arteriolar equivalents (CRAE) and central retinal venular equivalents (CRVE), were examined using digital retinal images taken in Multi-Ethnic Study of Atherosclerosis (MESA) participants between 2002 and 2003. Study participants (46 to 87 years of age) were without clinical cardiovascular disease at the baseline examination (2000–2002). Long-term outdoor concentrations of PM2.5 were estimated at each participant's home for the 2 years preceding the clinical exam using a spatio-temporal model. Short-term concentrations were assigned using outdoor measurements on the day preceding the clinical exam. Residential proximity to roadways was also used as an indicator of long-term traffic exposures. All associations were examined using linear regression models adjusted for subject-specific age, sex, race/ethnicity, education, income, smoking status, alcohol use, physical activity, body mass index, family history of cardiovascular disease, diabetes status, serum cholesterol, glucose, blood pressure, emphysema, C-reactive protein, medication use, and fellow vessel diameter. Short-term associations were further controlled for weather and seasonality. Among the 4,607 participants with complete data, CRAE were found to be narrower among persons residing in regions with increased long- and short-term levels of PM2.5. These relationships were observed in a joint exposure model with −0.8 µm (95% confidence interval [CI] −1.1 to −0

  13. Changes in ganglion cell physiology during retinal degeneration influence excitability by prosthetic electrodes

    NASA Astrophysics Data System (ADS)

    Cho, Alice; Ratliff, Charles; Sampath, Alapakkam; Weiland, James

    2016-04-01

    Objective. Here we investigate ganglion cell physiology in healthy and degenerating retina to test its influence on threshold to electrical stimulation. Approach. Age-related Macular Degeneration and Retinitis Pigmentosa cause blindness via outer retinal degeneration. Inner retinal pathways that transmit visual information to the central brain remain intact, so direct electrical stimulation from prosthetic devices offers the possibility for visual restoration. Since inner retinal physiology changes during degeneration, we characterize physiological properties and responses to electrical stimulation in retinal ganglion cells (RGCs) of both wild type mice and the rd10 mouse model of retinal degeneration. Main results. Our aggregate results support previous observations that elevated thresholds characterize diseased retinas. However, a physiology-driven classification scheme reveals distinct sub-populations of ganglion cells with thresholds either normal or strongly elevated compared to wild-type. When these populations are combined, only a weakly elevated threshold with large variance is observed. The cells with normal threshold are more depolarized at rest and exhibit periodic oscillations. Significance. During degeneration, physiological changes in RGCs affect the threshold stimulation currents required to evoke action potentials.

  14. The Unfolded Protein Response in Retinal Vascular Diseases: Implications and Therapeutic Potential Beyond Protein Folding

    PubMed Central

    Zhang, Sarah X.; Ma, Jacey H.; Bhatta, Maulasri; Fliesler, Steven J.; Wang, Joshua J.

    2015-01-01

    Angiogenesis is a complex, step-wise process of new vessel formation that is involved in both normal embryonic development as well as postnatal pathological processes, such as cancer, cardiovascular disease, and diabetes. Aberrant blood vessel growth, also known as neovascularization, in the retina and the choroid is a major cause of vision loss in severe eye diseases, such as diabetic retinopathy, age-related macular degeneration, retinopathy of prematurity, and central and branch retinal vein occlusion. Yet, retinal neovascularization is causally and dynamically associated with vasodegeneration, ischemia, and vascular remodeling in retinal tissues. Understanding the mechanisms of retinal neovascularization is an urgent unmet need for developing new treatments for these devastating diseases. Accumulating evidence suggests a vital role for the unfolded protein response (UPR) in regulation of angiogenesis, in part through coordinating the secretion of pro-angiogenic growth factors, such as VEGF, and modulating endothelial cell survival and activity. Herein, we summarize current research in the context of endoplasmic reticulum (ER) stress and UPR signaling in retinal angiogenesis and vascular remodeling, highlighting potential implications of targeting these stress response pathways in the prevention and treatment of retinal vascular diseases that result in visual deficits and blindness. PMID:25529848

  15. Retinal and post-retinal contributions to the quantum efficiency of the human eye revealed by electrical neuroimaging

    PubMed Central

    Manasseh, Gibran; de Balthasar, Chloe; Sanguinetti, Bruno; Pomarico, Enrico; Gisin, Nicolas; de Peralta, Rolando Grave; Andino, Sara L. Gonzalez

    2013-01-01

    The retina is one of the best known quantum detectors with rods able to reliably respond to single photons. However, estimates on the number of photons eliciting conscious perception, based on signal detection theory, are systematically above these values after discounting by retinal losses. One possibility is that there is a trade-off between the limited motor resources available to living systems and the excellent reliability of the visual photoreceptors. On this view, the limits to sensory thresholds are not set by the individual reliability of the receptors within each sensory modality (as often assumed) but rather by the limited central processing and motor resources available to process the constant inflow of sensory information. To investigate this issue, we reproduced the classical experiment from Hetch aimed to determine the sensory threshold in human vision. We combined a careful physical control of the stimulus parameters with high temporal/spatial resolution recordings of EEG signals and behavioral variables over a relatively large sample of subjects (12). Contrarily to the idea that the limits to visual sensitivity are fully set by the statistical fluctuations in photon absorption on retinal photoreceptors we observed that the state of ongoing neural oscillations before any photon impinges the retina helps to determine if the responses of photoreceptors have access to central conscious processing. Our results suggest that motivational and attentional off-retinal mechanisms play a major role in reducing the QE efficiency of the human visual system when compared to the efficiency of isolated retinal photoreceptors. Yet, this mechanism might subserve adaptive behavior by enhancing the overall multisensory efficiency of the whole system composed by diverse reliable sensory modalities. PMID:24302913

  16. Retinal and post-retinal contributions to the quantum efficiency of the human eye revealed by electrical neuroimaging.

    PubMed

    Manasseh, Gibran; de Balthasar, Chloe; Sanguinetti, Bruno; Pomarico, Enrico; Gisin, Nicolas; de Peralta, Rolando Grave; Andino, Sara L Gonzalez

    2013-01-01

    The retina is one of the best known quantum detectors with rods able to reliably respond to single photons. However, estimates on the number of photons eliciting conscious perception, based on signal detection theory, are systematically above these values after discounting by retinal losses. One possibility is that there is a trade-off between the limited motor resources available to living systems and the excellent reliability of the visual photoreceptors. On this view, the limits to sensory thresholds are not set by the individual reliability of the receptors within each sensory modality (as often assumed) but rather by the limited central processing and motor resources available to process the constant inflow of sensory information. To investigate this issue, we reproduced the classical experiment from Hetch aimed to determine the sensory threshold in human vision. We combined a careful physical control of the stimulus parameters with high temporal/spatial resolution recordings of EEG signals and behavioral variables over a relatively large sample of subjects (12). Contrarily to the idea that the limits to visual sensitivity are fully set by the statistical fluctuations in photon absorption on retinal photoreceptors we observed that the state of ongoing neural oscillations before any photon impinges the retina helps to determine if the responses of photoreceptors have access to central conscious processing. Our results suggest that motivational and attentional off-retinal mechanisms play a major role in reducing the QE efficiency of the human visual system when compared to the efficiency of isolated retinal photoreceptors. Yet, this mechanism might subserve adaptive behavior by enhancing the overall multisensory efficiency of the whole system composed by diverse reliable sensory modalities. PMID:24302913

  17. Retinal blood vessels extraction using probabilistic modelling.

    PubMed

    Kaba, Djibril; Wang, Chuang; Li, Yongmin; Salazar-Gonzalez, Ana; Liu, Xiaohui; Serag, Ahmed

    2014-01-01

    The analysis of retinal blood vessels plays an important role in detecting and treating retinal diseases. In this review, we present an automated method to segment blood vessels of fundus retinal image. The proposed method could be used to support a non-intrusive diagnosis in modern ophthalmology for early detection of retinal diseases, treatment evaluation or clinical study. This study combines the bias correction and an adaptive histogram equalisation to enhance the appearance of the blood vessels. Then the blood vessels are extracted using probabilistic modelling that is optimised by the expectation maximisation algorithm. The method is evaluated on fundus retinal images of STARE and DRIVE datasets. The experimental results are compared with some recently published methods of retinal blood vessels segmentation. The experimental results show that our method achieved the best overall performance and it is comparable to the performance of human experts.

  18. Role of retinal vascular endothelial cells in development of CMV retinitis.

    PubMed Central

    Rao, N A; Zhang, J; Ishimoto, S

    1998-01-01

    PURPOSE: Although cytomegalovirus (CMV) retinitis is known to occur in association with retinal microangiopathy in individuals with marked immunodeficiency, glial cells are believed to be the initial target cells in the development of retinitis. Moreover, it has been hypothesized that CMV gains access to the retinal glia because of altered vascular permeability. In an attempt to address the hypothesis, we studied 30 autopsy eyes of AIDS patients with systemic CMV infection, with or without clinically apparent CMV retinitis. METHODS: The autopsy eyes were processed in three ways. First, dual immunohistochemical studies were done by using anti-CMV antibodies for immediate early, early, and late antigens. The retinal cell types infected with the virus were then determined by using anti-GFAP, anti-VonWillebrand's factor, neuronal specific enolase, and leukocyte marker CD68. Second, selected eyes were processed for in situ hybridization with DNA probe specific to CMV. Third, an eye with clinically apparent CMV retinitis was submitted for electron microscopic examination. RESULTS: At the site of retinal necrosis in those eyes with a clinical diagnosis of CMV retinitis, the immunohistochemical, in situ hybridization, and ultrastructural examinations revealed that CMV was present primarily in the Müller cells and in perivascular glial cells. Adjacent to these infected cells, focal areas of positive staining for CMV antigen were seen in the glial cells, neuronal cells, and retinal pigment epithelial cells. At these sites most of the retinal capillaries were devoid of endothelial cells. Few vessels located at the advancing margin of retinal necrosis showed the presence of viral proteins in the endothelial cells. CONCLUSIONS: The present results indicate that retinal vascular endothelial cells could be the initial target in the development of viral retinitis, with subsequent spread of the infection to perivascular glia, Müller cells, and other retinal cells, including the

  19. The lymphoid chemokine, CXCL13, is dispensable for the initial recruitment of B cells to the acutely inflamed central nervous system

    PubMed Central

    Rainey-Barger, Emily K; Rumble, Julie M; Lalor, Stephen J.; Esen, Nilufer; Segal, Benjamin M; Irani, David N

    2010-01-01

    Cases of progressive multifocal leukoencephalopathy can occur in patients treated with the B cell depleting anti-CD20 antibody, rituximab, highlighting the importance of B cell surveillance of the central nervous system (CNS). The lymphoid chemokine, CXCL13, is critical for B cell recruitment and functional organization of peripheral lymphoid tissues, and CXCL13 levels are often elevated in the inflamed CNS. To more directly investigate the role of CXCL13 in CNS B cell migration, its role in animal models of infectious and inflammatory demyelinating disease was examined. During acute alphavirus encephalitis where viral clearance depends on the local actions of anti-viral antibodies, CXCL13 levels and B cell numbers increased in brain tissue over time. Surprisingly, however, CXCL13-deficient animals showed normal CNS B cell recruitment, unaltered CNS virus replication and clearance, and intact peripheral anti-viral antibody responses. During experimental autoimmune encephalomyelitis (EAE), CNS levels of CXCL13 increased as symptoms emerged and equivalent numbers of B cells were identified among the CNS infiltrates of CXCL13-deficient mice compared to control animals. However, CXCL13-deficient mice did not sustain pathogenic anti-myelin T cell responses, consistent with their known propensity to develop more self-limited EAE. These data show that CXCL13 is dispensable for CNS B cell recruitment in both models. The disease course is unaffected by CXCL13 in a CNS infection paradigm that depends on a pathogen-specific B cell response, while it is heightened and prolonged by CXCL13 when myelin-specific CD4+ T cells drive CNS pathology. Thus, CXCL13 could be a therapeutic target in certain neuroinflammatory diseases, but not by blocking B cell recruitment to the CNS. PMID:20933590

  20. Central nervous system involvement in adult acute lymphoblastic leukemia at diagnosis: results from the international ALL trial MRC UKALL XII/ECOG E2993

    PubMed Central

    Lazarus, Hillard M.; Richards, Susan M.; Chopra, Raj; Litzow, Mark R.; Burnett, Alan K.; Wiernik, Peter H.; Franklin, Ian M.; Tallman, Martin S.; Cook, Lucy; Buck, Georgina; Durrant, I. Jill; Rowe, Jacob M.; Goldstone, Anthony H.

    2006-01-01

    Outcome of acute lymphoblastic leukemia (ALL) in adults with central nervous system (CNS) disease at diagnosis is unclear. We treated 1508 de novo ALL patients with 2-phase induction and then high-dose methotrexate with l-asparaginase. Patients up to 50 years old in first remission (CR1) with a matched related donor (MRD) underwent an allogeneic stem cell transplantation (SCT); the remainder in CR1 were randomized to an autologous SCT or intensive consolidation followed by maintenance chemotherapy. Philadelphia chromosome (Ph)–positive patients were offered a matched unrelated donor (MUD) allogeneic SCT. Seventy-seven of 1508 (5%) patients a median age of 29 years had CNS leukemia at presentation; 13 of the 77 (17%) had Ph-positive ALL. Sixty-nine of 77 (90%) patients attained CR1. Thirty-six patients underwent transplantation in CR1 (25 MRD, 5 MUD, and 6 autografts). Eleven of 25 patients with MRD transplantation remain alive at 21 to 102 months, 2 of 5 with MUD at 42 and 71 months, and 1 of 6 with autologous SCT at 35 months. Seven of 27 treated with consolidation/maintenance remain in CR1 56 to 137 months after diagnosis. Overall survival at 5 years was 29% in those with CNS involvement at diagnosis versus 38% (P = .03) for those without. CNS leukemia in adult ALL is uncommon at diagnosis. Adult Ph-negative ALL patients, however, can attain long-term disease-free survival using SCT as well as conventional chemotherapy. PMID:16556888

  1. Impact of Cranial Irradiation Added to Intrathecal Conditioning in Hematopoietic Cell Transplantation in Adult Acute Myeloid Leukemia With Central Nervous System Involvement

    SciTech Connect

    Mayadev, Jyoti S.; Douglas, James G.; Storer, Barry E.; Appelbaum, Frederick R.; Storb, Rainer

    2011-05-01

    Purpose: Neither the prognostic importance nor the appropriate management of central nervous system (CNS) involvement is known for patients with acute myeloid leukemia (AML) undergoing hematopoietic cell transplantation (HCT). We examined the impact of a CNS irradiation boost to standard intrathecal chemotherapy (ITC). Methods and Materials: From 1995 to 2005, a total of 648 adult AML patients received a myeloablative HCT: 577 patients were CNS negative (CNS-), and 71 were CNS positive (CNS+). Of the 71 CNS+ patients, 52 received intrathecal chemotherapy alone (CNS+ITC), and 19 received ITC plus an irradiation boost (CNS+RT). Results: The CNS-, CNS+ITC, and CNS+RT patients had 1- and 5-year relapse-free survivals (RFS) of 43% and 35%, 15% and 6%, and 37% and 32%, respectively. CNS+ITC patients had a statistically significant worse RFS compared with CNS- patients (hazard ratio [HR], 2.65; 95% confidence interval [CI], 2.0-3.6; p < 0.0001). CNS+RT patients had improved relapse free survival over that of CNS+ITC patients (HR, 0.45; 95% CI, 0.2-0.8; p = 0.01). The 1- and 5-year overall survivals (OS) of patients with CNS-, CNS+ITC, and CNS+RT, were 50% and 38%, 21% and 6%, and 53% and 42%, respectively. The survival of CNS+RT were significantly better than CNS+ITC patients (p = 0.004). After adjusting for known risk factors, CNS+RT patients had a trend toward lower relapse rates and reduced nonrelapse mortality. Conclusions: CNS+ AML is associated with a poor prognosis. The role of a cranial irradiation boost to intrathecal chemotherapy appears to mitigate the risk of CNS disease, and needs to be further investigated to define optimal treatment strategies.

  2. Retinal vein occlusion: current treatment.

    PubMed

    Lattanzio, Rosangela; Torres Gimeno, Ana; Battaglia Parodi, Maurizio; Bandello, Francesco

    2011-01-01

    Retinal vein occlusion (RVO) is a pathology noted for more than 150 years. Although a lot has been written on the matter, it is still a frequent condition with multifactorial etiopathogenesis with many unclear aspects. The RVO pathogenesis has varied systemic and local implications that make it difficult to elaborate treatment guidelines. The management of the patient with RVO is very complex and a multidisciplinary approach is required in order to identify and correct the associated risk factors. Laser therapy remains the gold standard in RVO, but only modest functional improvement has been shown in branch retinal occlusion forms. Multicenter studies of intravitreal drugs present them as an option to combine with laser. Anti-vascular endothelial growth factor, corticosteroids and sustained-release implants are the future weapons to stop disease progression and get a better visual outcome. Consequently, it is useful to clarify some aspects of the pathology that allow a better patient management. PMID:20938213

  3. Retinal fibrosis in diabetic retinopathy.

    PubMed

    Roy, Sayon; Amin, Shruti; Roy, Sumon

    2016-01-01

    In response to injury, reparative processes are triggered to restore the damaged tissue; however, such processes are not always successful in rebuilding the original state. The formation of fibrous connective tissue is known as fibrosis, a hallmark of the reparative process. For fibrosis to be successful, delicately balanced cellular events involving cell proliferation, cell migration, and extracellular matrix (ECM) remodeling must occur in a highly orchestrated manner. While successful repair may result in a fibrous scar, this often restores structural stability and functionality to the injured tissue. However, depending on the functionality of the injured tissue, a fibrotic scar can have a devastating effect. For example, in the retina, fibrotic scarring may compromise vision and ultimately lead to blindness. In this review, we discuss some of the retinal fibrotic complications and highlight mechanisms underlying the development of retinal fibrosis in diabetic retinopathy.

  4. Gene Therapy for Retinal Diseases

    PubMed Central

    Samiy, Nasrollah

    2014-01-01

    Gene therapy has a growing research potential particularly in the field of ophthalmic and retinal diseases owing to three main characteristics of the eye; accessibility in terms of injections and surgical interventions, its immune-privileged status facilitating the accommodation to the antigenicity of a viral vector, and tight blood-ocular barriers which save other organs from unwanted contamination. Gene therapy has tremendous potential for different ocular diseases. In fact, the perspective of gene therapy in the field of eye research does not confine to exclusive monogenic ophthalmic problems and it has the potential to include gene based pharmacotherapies for non-monogenic problems such as age related macular disease and diabetic retinopathy. The present article has focused on how gene transfer into the eye has been developed and used to treat retinal disorders with no available therapy at present. PMID:25709778

  5. Retinal vein occlusion: current treatment.

    PubMed

    Lattanzio, Rosangela; Torres Gimeno, Ana; Battaglia Parodi, Maurizio; Bandello, Francesco

    2011-01-01

    Retinal vein occlusion (RVO) is a pathology noted for more than 150 years. Although a lot has been written on the matter, it is still a frequent condition with multifactorial etiopathogenesis with many unclear aspects. The RVO pathogenesis has varied systemic and local implications that make it difficult to elaborate treatment guidelines. The management of the patient with RVO is very complex and a multidisciplinary approach is required in order to identify and correct the associated risk factors. Laser therapy remains the gold standard in RVO, but only modest functional improvement has been shown in branch retinal occlusion forms. Multicenter studies of intravitreal drugs present them as an option to combine with laser. Anti-vascular endothelial growth factor, corticosteroids and sustained-release implants are the future weapons to stop disease progression and get a better visual outcome. Consequently, it is useful to clarify some aspects of the pathology that allow a better patient management.

  6. Retinitis pigmentosa in southern Africa.

    PubMed

    Greenberg, J; Bartmann, L; Ramesar, R; Beighton, P

    1993-11-01

    Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal disorders which are a common cause of genetic blindness. The relative frequencies of the different forms of RP in South Africa, as determined from the register at the DNA banking centre for RP at the Department of Human Genetics, University of Cape Town, are presented and discussed. Of the 125 families analysed, 29 (23%) showed autosomal dominant, 33 (27%) autosomal recessive and 3 (3%) X-linked inheritance. In 10 families the pedigree data were insufficient to allow accurate genetic subtyping and a further 50 patients were sporadic without a family history of RP or other syndromic features which would allow categorization. PMID:8313621

  7. Operational challenges of retinal prostheses.

    PubMed

    Schmid, Erich W; Fink, Wolfgang; Wilke, Robert

    2014-12-01

    Two computational models for research on retinal implants are presented. In the first model, the electric field produced by a multi-electrode array in a uniform retina is calculated. It is shown how cross talk of activated electrodes and the resulting bunching of field lines in monopole and dipole activation prevent high resolution imaging with retinal implants. Furthermore, it is demonstrated how sequential stimulation and multipolar stimulation may overcome this limitation. In the second model a target volume, i.e., a probe cylinder approximating a bipolar cell, in the retina is chosen, and the passive Heaviside cable equation is solved inside this target volume to calculate the depolarization of the cell membrane. The depolarization as a function of time indicates that shorter signals stimulate better as long as the current does not change sign during stimulation of the retina, i.e., mono-phasic stimulation. Both computational models are equally applicable to epiretinal, subretinal, and suprachoroidal vision implants. PMID:25443535

  8. Mitochondria mediates caspase-dependent and independent retinal cell death in Staphylococcus aureus endophthalmitis.

    PubMed

    Singh, P K; Kumar, A

    2016-01-01

    Bacterial endophthalmitis, a vision-threatening complication of ocular surgery or trauma, is characterized by increased intraocular inflammation and retinal tissue damage. Although significant vision loss in endophthalmitis has been linked to retinal cell death, the underlying mechanisms of cell death remain elusive. In this study, using a mouse model of Staphylococcus aureus endophthalmitis and cultured human retinal Müller glia (MIO-M1 cell line), we demonstrate that S. aureus caused significant apoptotic cell death in the mouse retina and Müller glia, as evidenced by increased number of terminal dUTP nick end labeling and Annexin V and propidium iodide-positive cells. Immunohistochemistry and western blot studies revealed the reduction in mitochondrial membrane potential (JC-1 staining), release of cytochrome c into the cytosol, translocation of Bax to the mitochondria and the activation of caspase-9 and -3 in S. aureus-infected retina/retinal cells. In addition, the activation of PARP-1 and the release of apoptosis inducing factor from mitochondria was also observed in S. aureus-infected retinal cells. Inhibition studies using pan-caspase (Q-VD-OPH) and PARP-1 (DPQ) inhibitors showed significant reduction in S. aureus-induced retinal cell death both in vivo and in vitro. Together, our findings demonstrate that in bacterial endophthalmitis, retinal cells undergo apoptosis in the both caspase-dependent and independent manners, and mitochondria have a central role in this process. Hence, targeting the identified signaling pathways may provide the rationale to design therapeutic interventions to prevent bystander retinal tissue damage in bacterial endophthalmitis. PMID:27551524

  9. Mitochondria mediates caspase-dependent and independent retinal cell death in Staphylococcus aureus endophthalmitis

    PubMed Central

    Singh, P K; Kumar, A

    2016-01-01

    Bacterial endophthalmitis, a vision-threatening complication of ocular surgery or trauma, is characterized by increased intraocular inflammation and retinal tissue damage. Although significant vision loss in endophthalmitis has been linked to retinal cell death, the underlying mechanisms of cell death remain elusive. In this study, using a mouse model of Staphylococcus aureus endophthalmitis and cultured human retinal Müller glia (MIO-M1 cell line), we demonstrate that S. aureus caused significant apoptotic cell death in the mouse retina and Müller glia, as evidenced by increased number of terminal dUTP nick end labeling and Annexin V and propidium iodide-positive cells. Immunohistochemistry and western blot studies revealed the reduction in mitochondrial membrane potential (JC-1 staining), release of cytochrome c into the cytosol, translocation of Bax to the mitochondria and the activation of caspase-9 and -3 in S. aureus-infected retina/retinal cells. In addition, the activation of PARP-1 and the release of apoptosis inducing factor from mitochondria was also observed in S. aureus-infected retinal cells. Inhibition studies using pan-caspase (Q-VD-OPH) and PARP-1 (DPQ) inhibitors showed significant reduction in S. aureus-induced retinal cell death both in vivo and in vitro. Together, our findings demonstrate that in bacterial endophthalmitis, retinal cells undergo apoptosis in the both caspase-dependent and independent manners, and mitochondria have a central role in this process. Hence, targeting the identified signaling pathways may provide the rationale to design therapeutic interventions to prevent bystander retinal tissue damage in bacterial endophthalmitis. PMID:27551524

  10. Mechanical Dissociation of Retinal Neurons with Vibration

    NASA Astrophysics Data System (ADS)

    Motomura, Tamami; Hayashida, Yuki; Murayama, Nobuki

    The neuromorphic device, which implements the functions of biological neural circuits by means of VLSI technology, has been collecting much attention in the engineering fields in the last decade. Concurrently, progress in neuroscience research has revealed the nonlinear computation in single neuron levels, suggesting that individual neurons are not merely the circuit elements but computational units. Thus, elucidating the properties of neuronal signal processing is thought to be an essential step for developing the next generation of neuromorphic devices. In the present study, we developed a method for dissociating single neurons from specific sublayers of mammalian retinas with using no proteolytic enzymes but rather combining tissue incubation in a low-Ca2+ medium and the vibro-dissociation technique developed for the slices of brains and spinal cords previously. Our method took shorter time of the procedure, and required less elaborated skill, than the conventional enzymatic method did; nevertheless it yielded enough number of the cells available for acute electrophysiological experiments. The isolated retinal neurons were useful for measuring the nonlinear membrane conductances as well as the spike firing properties under the perforated-patch whole-cell configuration. These neurons also enabled us to examine the effects of proteolytic enzymes on the membrane excitability in those cells.

  11. Acquired retinal folds in the cat.

    PubMed

    MacMillan, A D

    1976-06-01

    Retinal folds were found in 5 cats. The apparent cause of the folding was varied: in 1 cat the folds appeared after a localized retinal detachment; in 2 cats the condition accompanied other intraocular abnormalities associated with feline infectious peritonitis; 1 cat had active keratitis, and the retinal changes were thought to have been injury related; and 1 cat, bilaterally affected, had chronic glomerulonephritis. PMID:945253

  12. Aberrant protein trafficking in retinal degenerations: The initial phase of retinal remodeling.

    PubMed

    Bales, Katie L; Gross, Alecia K

    2016-09-01

    Retinal trafficking proteins are involved in molecular assemblies that govern protein transport, orchestrate cellular events involved in cilia formation, regulate signal transduction, autophagy and endocytic trafficking, all of which if not properly controlled initiate retinal degeneration. Improper function and or trafficking of these proteins and molecular networks they are involved in cause a detrimental cascade of neural retinal remodeling due to cell death, resulting as devastating blinding diseases. A universal finding in retinal degenerative diseases is the profound detection of retinal remodeling, occurring as a phased modification of neural retinal function and structure, which begins at the molecular level. Retinal remodeling instigated by aberrant trafficking of proteins encompasses many forms of retinal degenerations, such as the diverse forms of retinitis pigmentosa (RP) and disorders that resemble RP through mutations in the rhodopsin gene, retinal ciliopathies, and some forms of glaucoma and age-related macular degeneration (AMD). As a large majority of genes associated with these different retinopathies are overlapping, it is imperative to understand their underlying molecular mechanisms. This review will discuss some of the most recent discoveries in vertebrate retinal remodeling and retinal degenerations caused by protein mistrafficking. PMID:26632497

  13. Multineuronal codes in retinal signaling.

    PubMed Central

    Meister, M

    1996-01-01

    The visual world is presented to the brain through patterns of action potentials in the population of optic nerve fibers. Single-neuron recordings show that each retinal ganglion cell has a spatially restricted receptive field, a limited integration time, and a characteristic spectral sensitivity. Collectively, these response properties define the visual message conveyed by that neuron's action potentials. Since the size of the optic nerve is strictly constrained, one expects the retina to generate a highly efficient representation of the visual scene. By contrast, the receptive fields of nearby ganglion cells often overlap, suggesting great redundancy among the retinal output signals. Recent multineuron recordings may help resolve this paradox. They reveal concerted firing patterns among ganglion cells, in which small groups of nearby neurons fire synchronously with delays of only a few milliseconds. As there are many more such firing patterns than ganglion cells, such a distributed code might allow the retina to compress a large number of distinct visual messages into a small number of optic nerve fibers. This paper will review the evidence for a distributed coding scheme in the retinal output. The performance limits of such codes are analyzed with simple examples, illustrating that they allow a powerful trade-off between spatial and temporal resolution. PMID:8570603

  14. Retinal microvascular caliber and chronic kidney disease in an Asian population.

    PubMed

    Sabanayagam, Charumathi; Shankar, Anoop; Koh, David; Chia, Kee Seng; Saw, Seang Mei; Lim, Su Chi; Tai, E Shyong; Wong, Tien Yin

    2009-03-01

    Retinal arteriolar narrowing is a marker of microvascular damage from elevated blood pressure. Between August 2004 and June 2006, the authors examined the association between retinal vascular diameter and chronic kidney disease in a population-based cohort of 3,280 community-dwelling adults of Malay ethnicity aged 40-80 years living in Singapore. Chronic kidney disease was defined as 1) an estimated glomerular filtration rate (eGFR) of <60 mL/minute/1.73 m(2) from serum creatinine or 2) the presence of micro/macroalbuminuria defined as urinary albumin:creatinine ratios of > or = 17 mg/g for men and > or = 25 mg/g for women. Retinal arteriolar and venular diameters were measured and summarized as central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE). Individuals with reduced CRAE were more likely to have chronic kidney disease than those with increased CRAE. After controlling for age, gender, education, smoking, diabetes, hypertension, body mass index, and total and high density lipoprotein cholesterol, the authors found the odds ratio comparing the smallest with the largest CRAE quartile to be 1.42 (95% confidence interval: 1.03, 1.96; P(trend) = 0.02) for eGFR of <60 mL/minute/1.73 m(2) and 1.80 (95% confidence interval: 1.11, 2.91; P(trend) = 0.01) for micro/macroalbuminuria. Retinopathy was also found to be positively associated with both eGFR and micro/macroalbuminuria. Retinal venular diameter was not associated with chronic kidney disease. These data suggest that retinal arteriolar narrowing is associated with chronic kidney disease, independent of diabetes and hypertension. PMID:19092170

  15. Update on Pharmacologic Retinal Vascular Toxicity.

    PubMed

    Schwartz, Stephen G; Grzybowski, Andrzej; Wasinska-Borowiec, Weronika; Flynn, Harry W; Mieler, William F

    2015-01-01

    Several medications are associated with retinal vascular toxicity. These include intraocular aminoglycosides, oral contraceptives, interferon alpha, several other agents, and talc, which occurs as a vehicle in some oral medications that may be abused intravenously. As a group, these entities represent a small but clinically relevant category of retinal toxicity from medications. Some of the manifestations (e.g., retinal vascular occlusion) are nonspecific, but others are more specific, including clinically visible talc emboli in retinal vessels. Toxicity may be asymptomatic or may cause irreversible visual loss. By maintaining a high index of suspicion, the correct diagnosis can usually be made.

  16. Retinal Macroglial Responses in Health and Disease

    PubMed Central

    de Hoz, Rosa; Rojas, Blanca; Ramírez, Ana I.; Salazar, Juan J.; Gallego, Beatriz I.; Triviño, Alberto; Ramírez, José M.

    2016-01-01

    Due to their permanent and close proximity to neurons, glial cells perform essential tasks for the normal physiology of the retina. Astrocytes and Müller cells (retinal macroglia) provide physical support to neurons and supplement them with several metabolites and growth factors. Macroglia are involved in maintaining the homeostasis of extracellular ions and neurotransmitters, are essential for information processing in neural circuits, participate in retinal glucose metabolism and in removing metabolic waste products, regulate local blood flow, induce the blood-retinal barrier (BRB), play fundamental roles in local immune response, and protect neurons from oxidative damage. In response to polyetiological insults, glia cells react with a process called reactive gliosis, seeking to maintain retinal homeostasis. When malfunctioning, macroglial cells can become primary pathogenic elements. A reactive gliosis has been described in different retinal pathologies, including age-related macular degeneration (AMD), diabetes, glaucoma, retinal detachment, or retinitis pigmentosa. A better understanding of the dual, neuroprotective, or cytotoxic effect of macroglial involvement in retinal pathologies would help in treating the physiopathology of these diseases. The extensive participation of the macroglia in retinal diseases points to these cells as innovative targets for new drug therapies. PMID:27294114

  17. Retinal detachment associated with atopic dermatitis.

    PubMed Central

    Takahashi, M; Suzuma, K; Inaba, I; Ogura, Y; Yoneda, K; Okamoto, H

    1996-01-01

    BACKGROUND: Retinal detachment associated with atopic dermatitis, one of the most common forms of dermatitis in Japan, has markedly increased in Japan in the past 10 years. To clarify pathogenic mechanisms of retinal detachment in such cases, we retrospectively studied clinical characteristics of retinal detachment associated with atopic dermatitis. METHODS: We examined the records of 80 patients (89 eyes) who had retinal detachment associated with atopic dermatitis. The patients were classified into three groups according to lens status: group A, eyes with clear lenses (40 eyes); group B, eyes with cataract (38 eyes), and group C, aphakic or pseudophakic eyes (11 eyes). RESULTS: No significant differences were noted in the ratio of males to females, age distribution, refractive error, or characteristic of retinal detachment among the three groups. The types of retinal breaks, however, were different in eyes with and without lens changes. While atrophic holes were dominant in group A, retinal dialysis was mainly seen in groups B and C. CONCLUSION: These findings suggested that anterior vitreoretinal traction may play an important role in the pathogenesis of retinal breaks in eyes with atopic cataract and that the same pathological process may affect the formation of cataract and tractional retinal breaks in patients with atopic dermatitis. PMID:8664234

  18. Retinal Cell Degeneration in Animal Models

    PubMed Central

    Niwa, Masayuki; Aoki, Hitomi; Hirata, Akihiro; Tomita, Hiroyuki; Green, Paul G.; Hara, Akira

    2016-01-01

    The aim of this review is to provide an overview of various retinal cell degeneration models in animal induced by chemicals (N-methyl-d-aspartate- and CoCl2-induced), autoimmune (experimental autoimmune encephalomyelitis), mechanical stress (optic nerve crush-induced, light-induced) and ischemia (transient retinal ischemia-induced). The target regions, pathology and proposed mechanism of each model are described in a comparative fashion. Animal models of retinal cell degeneration provide insight into the underlying mechanisms of the disease, and will facilitate the development of novel effective therapeutic drugs to treat retinal cell damage. PMID:26784179

  19. Update on Pharmacologic Retinal Vascular Toxicity.

    PubMed

    Schwartz, Stephen G; Grzybowski, Andrzej; Wasinska-Borowiec, Weronika; Flynn, Harry W; Mieler, William F

    2015-01-01

    Several medications are associated with retinal vascular toxicity. These include intraocular aminoglycosides, oral contraceptives, interferon alpha, several other agents, and talc, which occurs as a vehicle in some oral medications that may be abused intravenously. As a group, these entities represent a small but clinically relevant category of retinal toxicity from medications. Some of the manifestations (e.g., retinal vascular occlusion) are nonspecific, but others are more specific, including clinically visible talc emboli in retinal vessels. Toxicity may be asymptomatic or may cause irreversible visual loss. By maintaining a high index of suspicion, the correct diagnosis can usually be made. PMID:26350526

  20. Hypoxia-Induced Retinal Neovascularization in Zebrafish Embryos: A Potential Model of Retinopathy of Prematurity

    PubMed Central

    Kao, Alex; Hsi, Brian; Lee, Shwu-Huey; Chen, Yau-Hung; Wang, I-Jong

    2015-01-01

    Retinopathy of prematurity, formerly known as a retrolental fibroplasia, is a leading cause of infantile blindness worldwide. Retinopathy of prematurity is caused by the failure of central retinal vessels to reach the retinal periphery, creating a nonperfused peripheral retina, resulting in retinal hypoxia, neovascularization, vitreous hemorrhage, vitreoretinal fibrosis, and loss of vision. We established a potential retinopathy of prematurity model by using a green fluorescent vascular endothelium zebrafish transgenic line treated with cobalt chloride (a hypoxia-inducing agent), followed by GS4012 (a vascular endothelial growth factor inducer) at 24 hours postfertilization, and observed that the number of vascular branches and sprouts significantly increased in the central retinal vascular trunks 2–4 days after treatment. We created an angiography method by using tetramethylrhodamine dextran, which exhibited severe vascular leakage through the vessel wall into the surrounding retinal tissues. The quantification of mRNA extracted from the heads of the larvae by using real-time quantitative polymerase chain reaction revealed a twofold increase in vegfaa and vegfr2 expression compared with the control group, indicating increased vascular endothelial growth factor signaling in the hypoxic condition. In addition, we demonstrated that the hypoxic insult could be effectively rescued by several antivascular endothelial growth factor agents such as SU5416, bevacizumab, and ranibizumab. In conclusion, we provide a simple, highly reproducible, and clinically relevant retinopathy of prematurity model based on zebrafish embryos; this model may serve as a useful platform for clarifying the mechanisms of human retinopathy of prematurity and its progression. PMID:25978439

  1. Crewmembers in the middeck with the Retinal Photography experiment.

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Mission Pilot Robert Cabana conducting the Retinal Photography life sciences experiment on test subject Mission Specialist Michael Clifford. The Retinal Photography experiment is Detailed Supplementary Objective # 474.

  2. Polymerase chain reaction analysis of aqueous humour samples in necrotising retinitis

    PubMed Central

    Tran, T H C; Rozenberg, F; Cassoux, N; Rao, N A; LeHoang, P; Bodaghi, B

    2003-01-01

    Aim: To evaluate the diagnostic value of polymerase chain reaction (PCR) performed on aqueous humour for the detection of viral DNA in patients with necrotising herpetic retinitis. Methods: The clinical features and laboratory results of 22 patients (29 eyes) presenting with necrotising herpetic retinitis between March 1999 and June 2001 were reviewed retrospectively. Aqueous humour was obtained after anterior chamber paracentesis and PCR was performed in all cases. Results: Viral DNA was detected in the aqueous humour of 19 patients (86.4%). Epstein-Barr virus (EBV) seroconversion was evidenced in one additional patient. In the acute retinal necrosis (ARN) group (n = 19), varicella zoster virus (VZV) DNA was identified in six patients, herpes simplex virus 1 (HSV-1) DNA in two patients, herpes simplex virus 2 (HSV-2) DNA in four patients, and cytomegalovirus (CMV) genome in four patients. In the progressive outer retinal necrosis (PORN) group (n = 3), VZV DNA was detected in all patients. No sample was positive for more than one virus. Conclusions: PCR analysis of aqueous humour in patients with clinical features of necrotising viral retinitis can provide specific aetiological orientation and the method appears to be safe and highly sensitive. PMID:12488268

  3. Herpetic (non-cytomegalovirus) retinal infections in patients with the acquired immunodeficiency syndrome.

    PubMed

    Stewart, Michael W

    2013-04-01

    Human herpes viruses cause significant morbidity in patients with the acquired immunodeficiency syndrome. Even after the introduction of highly active anti-retroviral therapy (HAART), herpes viruses remain the leading causes of blindness in AIDS patients. Cytomegalovirus (CMV) retinitis and the closely-related immune reconstitution uveitis syndrome are the most common causes of blindness, but progressive outer retinal necrosis and acute retinal necrosis due to varicella zoster and herpes simplex are also important causes of vision loss. Successful treatment of these conditions requires an aggressive approach with multi-drug intravenous therapy or repeated intravitreal antiviral injections. Since the rate of retinal detachment is alarmingly high despite successful antiviral therapy, internists and ophthalmologists must work closely together to recognize and treat complications as they arise. Fortunately, Epstein-Barr virus is a rare cause of retinal infection and human herpes virus (HHV)-6, HHV-7, and HHV-8 do not appear to be primary pathogens. However, increasing evidence suggests that HHV-6 and HHV-7 play important roles in modulating the immune system and potentiating infection by CMV.

  4. Retinal pigment epithelium transplantation: concepts, challenges, and future prospects

    PubMed Central

    Alexander, P; Thomson, H A J; Luff, A J; Lotery, A J

    2015-01-01

    The retinal pigment epithelium (RPE) is a single layer of cells that supports the light-sensitive photoreceptor cells that are essential for retinal function. Age-related macular degeneration (AMD) is a leading cause of visual impairment, and the primary pathogenic mechanism is thought to arise in the RPE layer. RPE cell structure and function are well understood, the cells are readily sustainable in laboratory culture and, unlike other cell types within the retina, RPE cells do not require synaptic connections to perform their role. These factors, together with the relative ease of outer retinal imaging, make RPE cells an attractive target for cell transplantation compared with other cell types in the retina or central nervous system. Seminal experiments in rats with an inherited RPE dystrophy have demonstrated that RPE transplantation can prevent photoreceptor loss and maintain visual function. This review provides an update on the progress made so far on RPE transplantation in human eyes, outlines potential sources of donor cells, and describes the technical and surgical challenges faced by the transplanting surgeon. Recent advances in the understanding of pluripotent stem cells, combined with novel surgical instrumentation, hold considerable promise, and support the concept of RPE transplantation as a regenerative strategy in AMD. PMID:26043704

  5. Retinal pigment epithelium transplantation: concepts, challenges, and future prospects.

    PubMed

    Alexander, P; Thomson, H A J; Luff, A J; Lotery, A J

    2015-08-01

    The retinal pigment epithelium (RPE) is a single layer of cells that supports the light-sensitive photoreceptor cells that are essential for retinal function. Age-related macular degeneration (AMD) is a leading cause of visual impairment, and the primary pathogenic mechanism is thought to arise in the RPE layer. RPE cell structure and function are well understood, the cells are readily sustainable in laboratory culture and, unlike other cell types within the retina, RPE cells do not require synaptic connections to perform their role. These factors, together with the relative ease of outer retinal imaging, make RPE cells an attractive target for cell transplantation compared with other cell types in the retina or central nervous system. Seminal experiments in rats with an inherited RPE dystrophy have demonstrated that RPE transplantation can prevent photoreceptor loss and maintain visual function. This review provides an update on the progress made so far on RPE transplantation in human eyes, outlines potential sources of donor cells, and describes the technical and surgical challenges faced by the transplanting surgeon. Recent advances in the understanding of pluripotent stem cells, combined with novel surgical instrumentation, hold considerable promise, and support the concept of RPE transplantation as a regenerative strategy in AMD. PMID:26043704

  6. Second harmonic generation from Langmuir-Blodgett films of retinal and retinal Schiff bases

    SciTech Connect

    Huang, J.; Lewis, A.; Rasing, T.

    1988-04-07

    The second harmonic signal from monolayers of retinal and retinal Schiff bases is reported. The results have yielded information on the monolayer structure and demonstrate that retinal and retinal Schiff bases have large second-order molecular hyperpolarizabilities with values of 1.4 x 10/sup -28/, 1.2 x 10/sup -28/, and 2.3 x 10/sup -28/ esu for retinal, the unprotonated Schiff base, and the protonated Schiff base, respectively. These values compare well with the known variation in the alteration in the dipole moment of such chromophores upon excitation.

  7. Anti-VEGF Therapy for Retinal Vein Occlusions.

    PubMed

    Campa, Claudio; Alivernini, Giuseppe; Bolletta, Elena; Parodi, Maurizio Battaglia; Perri, Paolo

    2016-01-01

    Retinal vein occlusion (RVO) is the second most common cause of visual loss in the Western World. RVO is usually classified into branch RVO (BRVO) and central RVO (CRVO) according to the anatomical site of the vascular occlusion. The pathogenesis of RVO is not yet fully understood, however an important event is the intraluminal thrombus formation, which is usually secondary to several conditions such as hypertension, hyperlipidemia, diabetes and thrombophilia. The blockage of venous circulation causes an elevation of intraluminal pressure in the capillaries, leading to hemorrhages and leakage of fluid within the retina, increase of interstitial pressure and a consequent reduction of retinal perfusion. Ischemia may develop resulting in secretion of vascular endothelial growth factor (VEGF) that causes further vascular leakage and retinal oedema. VEGF has therefore a leading role in RVO pathogenesis and symptoms. As a consequence use of anti-VEGF agents by intravitreal injections has become very common with the aim to improve the clinical outcomes in these patients. Currently 2 anti-VEGF agents (ranimizumab and aflibercept) have been FDA (Food and Drug Administration) and EMA (European Medicine Agency) approved for the treatment of RVO, while another VEGF inhibitor (bevacizumab) is often used "off-label" in clinical practice. Many treatment regimens have been suggested in the clinical trials with these drugs, as monthly injections or injections when needed, however the ideal regimen has not been defined yet. We conducted a systematic review searching MEDLINE for the following terms: retinal vein occlusion, ranibizumab, bevacizumab, aflibercept, vascular endothelial growth factor, macular oedema. Data were extracted by one author (AG and BE) and checked by a second (BPM, CC). Aim of this article was to review available data for each drug, focusing on their efficacy and safety trying to compare their advantages and limits.

  8. Optical properties of retinal tissue and the potential of adaptive optics to visualize retinal ganglion cells in vivo.

    PubMed

    Prasse, Martina; Rauscher, Franziska Georgia; Wiedemann, Peter; Reichenbach, Andreas; Francke, Mike

    2013-08-01

    Many efforts have been made to improve the diagnostic tools used to identify and to estimate the progress of ganglion cell and nerve fibre degeneration in glaucoma. Imaging by optical coherence tomography and measurements of the dimensions of the optic nerve head and the nerve fibre layer in central retinal areas is currently used to estimate the grade of pathological changes. The visualization and quantification of ganglion cells and nerve fibres directly in patients would dramatically improve glaucoma diagnostics. We have investigated the optical properties of cellular structures of retinal tissue in order to establish a means of visualizing and quantifying ganglion cells in the living retina without staining. We have characterized the optical properties of retinal tissue in several species including humans. Nerve fibres, blood vessels, ganglion cells and their cell processes have been visualized at high image resolution by means of the reflection mode of a confocal laser scanning microscope. The potential of adaptive optics in current imaging systems and the possibilities of imaging single ganglion cells non-invasively in patients are discussed.

  9. Caffeine administration prevents retinal neuroinflammation and loss of retinal ganglion cells in an animal model of glaucoma

    PubMed Central

    Madeira, Maria H.; Ortin-Martinez, Arturo; Nadal-Nícolas, Francisco; Ambrósio, António F.; Vidal-Sanz, Manuel; Agudo-Barriuso, Marta; Santiago, Ana Raquel

    2016-01-01

    Glaucoma is the second leading cause of blindness worldwide, being characterized by progressive optic nerve damage and loss of retinal ganglion cells (RGCs), accompanied by increased inflammatory response involving retinal microglial cells. The etiology of glaucoma is still unknown, and despite elevated intraocular pressure (IOP) being a major risk factor, the exact mechanisms responsible for RGC degeneration remain unknown. Caffeine, which is an antagonist of adenosine receptors, is the most widely consumed psychoactive drug in the world. Several evidences suggest that caffeine can attenuate the neuroinflammatory responses and afford protection upon central nervous system (CNS) injury. We took advantage of a well characterized animal model of glaucoma to investigate whether caffeine administration controls neuroinflammation and elicits neuroprotection. Caffeine or water were administered ad libitum and ocular hypertension (OHT) was induced by laser photocoagulation of the limbal veins in Sprague Dawley rats. Herein, we show that caffeine is able to partially decrease the IOP in ocular hypertensive animals. More importantly, we found that drinking caffeine prevented retinal microglia-mediated neuroinflammatory response and attenuated the loss of RGCs in animals with ocular hypertension (OHT). This study opens the possibility that caffeine or adenosine receptor antagonists might be a therapeutic option to manage RGC loss in glaucoma. PMID:27270337

  10. The bacterial toxin CNF1 as a tool to induce retinal degeneration reminiscent of retinitis pigmentosa

    PubMed Central

    Guadagni, Viviana; Cerri, Chiara; Piano, Ilaria; Novelli, Elena; Gargini, Claudia; Fiorentini, Carla; Caleo, Matteo; Strettoi, Enrica

    2016-01-01

    Retinitis pigmentosa (RP) comprises a group of inherited pathologies characterized by progressive photoreceptor degeneration. In rodent models of RP, expression of defective genes and retinal degeneration usually manifest during the first weeks of postnatal life, making it difficult to distinguish consequences of primary genetic defects from abnormalities in retinal development. Moreover, mouse eyes are small and not always adequate to test pharmacological and surgical treatments. An inducible paradigm of retinal degeneration potentially extensible to large animals is therefore desirable. Starting from the serendipitous observation that intraocular injections of a Rho GTPase activator, the bacterial toxin Cytotoxic Necrotizing Factor 1 (CNF1), lead to retinal degeneration, we implemented an inducible model recapitulating most of the key features of Retinitis Pigmentosa. The model also unmasks an intrinsic vulnerability of photoreceptors to the mechanism of CNF1 action, indicating still unexplored molecular pathways potentially leading to the death of these cells in inherited forms of retinal degeneration. PMID:27775019

  11. Retinal nerve fiber layer thickness and retinal vessel calibers in children with thalassemia minor

    PubMed Central

    Acer, Semra; Balcı, Yasemin I; Pekel, Gökhan; Ongun, Tuğba T; Polat, Aziz; Çetin, Ebru N; Yağcı, Ramazan

    2016-01-01

    Objectives: Evaluation of the peripapillary retinal nerve fiber layer thickness, subfoveal choroidal thickness, and retinal vessel caliber measurements in children with thalassemia minor. Methods: In this cross-sectional and comparative study, 30 thalassemia minor patients and 36 controls were included. Heidelberg spectral domain optical coherence tomography was used for peripapillary retinal nerve fiber layer thickness, subfoveal choroidal thickness, and retinal vessel caliber measurements. Results: There was no statistically significant difference in retinal nerve fiber layer thickness and subfoveal choroidal thickness between the two groups (p > 0.05). There was no correlation between retinal nerve fiber layer thickness and hemoglobin values. Both the arterioral and venular calibers were higher in thalassemia minor group (p < 0.05). Conclusion: There is increased retinal arterioral and venular calibers in children with thalassemia minor compared with controls. PMID:27540484

  12. Hard Retinal exudates and visual loss due to papilledema

    SciTech Connect

    Rush, J.A.

    1982-02-01

    Bilateral papilledema developed in a patient with a cystic, grade 3 astrocytoma of the right frontal lobe. Despite successful neurosurgical treatment, /sup 60/Co radiotherapy, and oral corticosteroid therapy, progressive visual loss occurred. At examination one year later, visual activity was 20/200 and 20/70, and extensive lipid exudates in the peripapillary retina and central macula of each eye were noted. Retinal lipid exudates rarely complicate the course of surviving patients who had papilledema from intracranial tumor; physicians involved in the multispecialty care of such patients should be aware of the possible ocular residuals of persistent papilledema in an otherwise successfully treated patient.

  13. Endophthalmitis with retinal necrosis following intravitreal triamcinolone acetonide injection.

    PubMed

    Aggermann, Tina; Stolba, Ulrike; Brunner, Simon; Binder, Susanne

    2006-01-01

    A 69-year-old man with heterozygote factor V Leiden mutation and a history of central retinal vein occlusion in his left eye complained of decreased visual acuity in his right eye. Macular edema and ischemic CRVO were diagnosed. Following an intravitreal injection of 4 mg triamcinolone acetonide, endophthalmitis and necrotizing retinopathy developed, clinically resembling necrotizing herpetic retinopathies as have been described in immuno-compromised patients. An endogenous viral infection due to a steroid-induced immune suppression may be another complication of intravitreal injections of corticosteroids.

  14. Tri-functional cannula for retinal endovascular surgery

    DOEpatents

    Weiss, Jonathan D.

    2010-07-27

    A tri-functional cannula combines the functions of tissue Plasminogen Activator (tPA) solution delivery, illumination and venous pressure measurement. The cannula utilizes a tapered hollow-core optical fiber having an inlet for tPA solution, an attached fiber optic splitter configured to receive illumination light from an optical source such and a LED. A window in the cannula transmits the light to and from a central retinal vein. The return light is coupled to an optical detector to measure the pressure within the vein and determine whether an occlusion has been removed.

  15. Retinal imaging as a source of biomarkers for diagnosis, characterization and prognosis of chronic illness or long-term conditions.

    PubMed

    MacGillivray, T J; Trucco, E; Cameron, J R; Dhillon, B; Houston, J G; van Beek, E J R

    2014-08-01

    The black void behind the pupil was optically impenetrable before the invention of the ophthalmoscope by von Helmholtz over 150 years ago. Advances in retinal imaging and image processing, especially over the past decade, have opened a route to another unexplored landscape, the retinal neurovascular architecture and the retinal ganglion pathways linking to the central nervous system beyond. Exploiting these research opportunities requires multidisciplinary teams to explore the interface sitting at the border between ophthalmology, neurology and computing science. It is from the detail and depth of retinal phenotyping that novel metrics and candidate biomarkers are likely to emerge. Confirmation that in vivo retinal neurovascular measures are predictive of microvascular change in the brain and other organs is likely to be a major area of research activity over the next decade. Unlocking this hidden potential within the retina requires integration of structural and functional data sets, that is, multimodal mapping and longitudinal studies spanning the natural history of the disease process. And with further advances in imaging, it is likely that this area of retinal research will remain active and clinically relevant for many years to come. Accordingly, this review looks at state-of-the-art retinal imaging and its application to diagnosis, characterization and prognosis of chronic illness or long-term conditions. PMID:24936979

  16. Retinal imaging as a source of biomarkers for diagnosis, characterization and prognosis of chronic illness or long-term conditions

    PubMed Central

    Trucco, E; Cameron, J R; Dhillon, B; Houston, J G; van Beek, E J R

    2014-01-01

    The black void behind the pupil was optically impenetrable before the invention of the ophthalmoscope by von Helmholtz over 150 years ago. Advances in retinal imaging and image processing, especially over the past decade, have opened a route to another unexplored landscape, the retinal neurovascular architecture and the retinal ganglion pathways linking to the central nervous system beyond. Exploiting these research opportunities requires multidisciplinary teams to explore the interface sitting at the border between ophthalmology, neurology and computing science. It is from the detail and depth of retinal phenotyping that novel metrics and candidate biomarkers are likely to emerge. Confirmation that in vivo retinal neurovascular measures are predictive of microvascular change in the brain and other organs is likely to be a major area of research activity over the next decade. Unlocking this hidden potential within the retina requires integration of structural and functional data sets, that is, multimodal mapping and longitudinal studies spanning the natural history of the disease process. And with further advances in imaging, it is likely that this area of retinal research will remain active and clinically relevant for many years to come. Accordingly, this review looks at state-of-the-art retinal imaging and its application to diagnosis, characterization and prognosis of chronic illness or long-term conditions. PMID:24936979

  17. Fundus autofluorescence applications in retinal imaging

    PubMed Central

    Gabai, Andrea; Veritti, Daniele; Lanzetta, Paolo

    2015-01-01

    Fundus autofluorescence (FAF) is a relatively new imaging technique that can be used to study retinal diseases. It provides information on retinal metabolism and health. Several different pathologies can be detected. Peculiar AF alterations can help the clinician to monitor disease progression and to better understand its pathogenesis. In the present article, we review FAF principles and clinical applications. PMID:26139802

  18. Argus II retinal prosthesis system: An update.

    PubMed

    Rachitskaya, Aleksandra V; Yuan, Alex

    2016-09-01

    This review focuses on a description of the Argus II retinal prosthesis system (Argus II; Second Sight Medical Products, Sylmar, CA) that was approved for humanitarian use by the FDA in 2013 in patients with retinitis pigmentosa with bare or no light perception vision. The article describes the components of Argus II, the studies on the implant, and future directions. PMID:26855177

  19. Double Dissociation of Monoacylglycerol Lipase Inhibition and CB1 Antagonism in the Central Amygdala, Basolateral Amygdala, and the Interoceptive Insular Cortex on the Affective Properties of Acute Naloxone-Precipitated Morphine Withdrawal in Rats.

    PubMed

    Wills, Kiri L; Petrie, Gavin N; Millett, Geneva; Limebeer, Cheryl L; Rock, Erin M; Niphakis, Micah J; Cravatt, Benjamin F; Parker, Linda A

    2016-06-01

    Both CB1 receptor antagonism and agonism, in particular by 2-arachidonyl glycerol (2-AG), have been shown to reduce somatic symptoms of morphine withdrawal (MWD). Here we evaluated the effects of both systemic pretreatment with the monoacylglycerol lipase (MAGL) inhibitor MJN110 (which selectively elevates 2-AG) and central administration of both MJN110 and the CB1 antagonist (AM251) on the affective properties of MWD. Acute MWD induced place aversion occurs when naloxone is administered 24 h following a single exposure to a high dose of morphine. Systemic pretreatment with the MAGL inhibitor, MJN110, prevented the aversive effects of acute MWD by a CB1 receptor-dependent mechanism. Furthermore, in a double dissociation, AM251 infusions into the central amygdala, but MJN110 infusions into the basolateral amygdala, interfered with the naloxone-precipitated MWD induced place aversion. As well, MJN110, but not AM251, infusions into the interoceptive insular cortex (a region known to be activated in acute MWD) also prevented the establishment of the place aversion by a CB1 mechanism of action. These findings reveal the respective sites of action of systemically administered MJN110 and AM251 in regulating the aversive effects of MWD.

  20. [Diffuse retinal pigment epitheliopathy and corticoid ointment topical treatment in a patient with psoriasis].

    PubMed

    Romero, P; Martinez, I; Salvat, M

    2005-12-01

    Central serous chorioretinopathy has three patterns: the first or typical form with one or several points of diffusion; the second, diffuse retinal pigment epitheliopathy; and the third, the bullous form of serous chorioretinopathy. The authors present a case of a 55-year-old male presenting with diffuse retinal pigment epitheliopathy and topical treatment of psoriasis, with a 9-year history of corticoid ointment use, associated with cyclosporine over the last year. The topical treatment was discontinued and the patient recovered his vision, with a final visual acuity of 5/10 in the right eye and 4/10 in the left eye.

  1. The cell stress machinery and retinal degeneration.

    PubMed

    Athanasiou, Dimitra; Aguilà, Monica; Bevilacqua, Dalila; Novoselov, Sergey S; Parfitt, David A; Cheetham, Michael E

    2013-06-27

    Retinal degenerations are a group of clinically and genetically heterogeneous disorders characterised by progressive loss of vision due to neurodegeneration. The retina is a highly specialised tissue with a unique architecture and maintaining homeostasis in all the different retinal cell types is crucial for healthy vision. The retina can be exposed to a variety of environmental insults and stress, including light-induced damage, oxidative stress and inherited mutations that can lead to protein misfolding. Within retinal cells there are different mechanisms to cope with disturbances in proteostasis, such as the heat shock response, the unfolded protein response and autophagy. In this review, we discuss the multiple responses of the retina to different types of stress involved in retinal degenerations, such as retinitis pigmentosa, age-related macular degeneration and glaucoma. Understanding the mechanisms that maintain and re-establish proteostasis in the retina is important for developing new therapeutic approaches to fight blindness. PMID:23684651

  2. [Intravitreal ganciclovir in cytomegalovirus retinitis in AIDS].

    PubMed

    Olea, J L; Salvat, M; Mateos, J M; Vila, J; Villalonga, C; Riera, M

    1996-04-01

    A retrospective study was made of 26 patients with AIDS who initially presented with retinitis as the only clinical manifestation of cytomegalovirus infection (39 eyes). Sixty-five induction or re-induction therapeutic courses were administered with intravitreal ganciclovir. The efficiency rate of therapy was 93.8%. Thirty-eight maintenance therapeutic courses (200 micrograms/week) were evaluated. The non-compliance rate was 23%. Bilateral retinitis occurred in 44.4% of cases. The systemic administration of therapy had to be substituted for the intravitreal administration in 32% of patients during the clinical course of their conditions. The mean survival rate was 9.5 months. Both retinal detachment and vitreal hemorrhage occurred in 5% of patients. When retinitis is the first clinical manifestation of cytomegalovirus infection, therapy with intravitreal ganciclovir is efficacious to inactivate lesions. Although bilateral retinitis and extraocular dissemination are common, the mean survival rate is high.

  3. Two Ocular Infections during Conventional Chemotherapy in a Patient with Acute Lymphoblastic Leukemia: A Case Report

    PubMed Central

    Taha, Ruba; Al Hijji, Ibrahim; El Omri, Halima; Al-Laftah, Fareed; Negm, Riham; Yassin, Mohammed; El Ayoubi, Hanadi

    2010-01-01

    Viral retinitis due to cytomegalovirus (CMV) infection is rare in patients with acute leukemia who did not receive hematopoietic stem cell transplantation. We report a case of CMV retinitis that developed in a 49-year-old patient with acute lymphoblastic leukemia. The patient was treated with salvage chemotherapy using a hyper-CVAD regimen and did not receive hematopoietic stem cell transplantation. The incidence of CMV retinitis in this subgroup of patients is not described in literature. He had a very complicated course during chemotherapy but was successfully treated, with preservation of visual acuity, and to date he is in complete remission. Interestingly, prior to CMV retinitis, the patient had been diagnosed with and treated for candida retinitis. This case shows the importance of eye examination and care in patients diagnosed with hematological malignancies. PMID:20740203

  4. Re-evaluating the treatment of acute optic neuritis

    PubMed Central

    Bennett, Jeffrey L; Nickerson, Molly; Costello, Fiona; Sergott, Robert C; Calkwood, Jonathan C; Galetta, Steven L; Balcer, Laura J; Markowitz, Clyde E; Vartanian, Timothy; Morrow, Mark; Moster, Mark L; Taylor, Andrew W; Pace, Thaddeus W W; Frohman, Teresa; Frohman, Elliot M

    2015-01-01

    Clinical case reports and prospective trials have demonstrated a reproducible benefit of hypothalamic-pituitary-adrenal (HPA) axis modulation on the rate of recovery from acute inflammatory central nervous system (CNS) demyelination. As a result, corticosteroid preparations and adrenocorticotrophic hormones are the current mainstays of therapy for the treatment of acute optic neuritis (AON) and acute demyelination in multiple sclerosis. Despite facilitating the pace of recovery, HPA axis modulation and corticosteroids have failed to demonstrate long-term benefit on functional recovery. After AON, patients frequently report visual problems, motion perception difficulties and abnormal depth perception despite ‘normal’ (20/20) vision. In light of this disparity, the efficacy of these and other therapies for acute demyelination require re-evaluation using modern, high-precision paraclinical tools capable of monitoring tissue injury. In no arena is this more amenable than AON, where a new array of tools in retinal imaging and electrophysiology has advanced our ability to measure the anatomic and functional consequences of optic nerve injury. As a result, AON provides a unique clinical model for evaluating the treatment response of the derivative elements of acute inflammatory CNS injury: demyelination, axonal injury and neuronal degeneration. In this article, we examine current thinking on the mechanisms of immune injury in AON, discuss novel technologies for the assessment of optic nerve structure and function, and assess current and future treatment modalities. The primary aim is to develop a framework for rigorously evaluating interventions in AON and to assess their ability to preserve tissue architecture, re-establish normal physiology and restore optimal neurological function. PMID:25355373

  5. Acute and long-term nutrient-led modifications of gene expression: potential role of SIRT1 as a central co-ordinator of short and longer-term programming of tissue function.

    PubMed

    Holness, Mark J; Caton, Paul W; Sugden, Mary C

    2010-05-01

    Environmental factors can influence the acute and longer-term risks of developing diseases, including type 2 diabetes mellitus and cardiovascular disease; however, the underlying mechanism remains elusive. Increasing evidence suggests that these effects can be achieved by modification of metabolic gene expression. These include acute changes in histone methylation, acetylation, phosphorylation, and ubiquitination and longer-term DNA silencing elicited by DNA methylation. Thus, an increased risk of disease may reflect acute or chronic stable modification of genes that regulate nutrient handling, leading to altered nutrient utilization (increased lipid oxidation at the expense of glucose utilization) and/or changes in the balance between nutrient storage and energy production, thereby favoring the development of obesity. The review addresses the hypothesis that early-life epigenetic programming of gene expression could be mirrored by changes in acute function of nuclear receptors, in particular the peroxisome proliferator-activated receptors, achieved by enzymes that are more conventionally involved in regulating DNA methylation and post-transcriptional modification of histones. Emphasis is placed on the potential importance of the protein deacetylase sirtuin-1 as a central co-ordinator.

  6. Primary Reactions in Retinal Proteins

    NASA Astrophysics Data System (ADS)

    Diller, R.

    Conversion of sunlight into energy or information and their storage on a chemical level is essential for life on earth. An important family of chromoproteins performing these tasks is that of retinal binding proteins. Prominent examples are rhodopsin (Rh) [1,2] as the visual pigment in vertebrate and invertebrate animals, the archaeal rhodopsins bacteriorhodopsin (BR) [3] as a light driven proton pump, halorhodopsin (HR) [4,5] as a light driven chloride pump, sensory rhodopsin I and II (SRI, SRII) [6] as photoreceptors, and proteorhodopsin (PR) [7] as another bacterial proton pump.

  7. A prototype retinal prosthesis for visual stimulation.

    PubMed

    Abu-Faraj, Ziad O; Rjeily, Dany M Abou; Nasreddine, Rayan W; Andari, Majid A; Taok, Habib H

    2007-01-01

    Vision loss has severe impacts on its victims, carrying with it physiological, psychological, social, and economic consequences thereby degrading the quality of life and depriving the individual from performing many of the daily living activities. This article describes the design and development of a prototype retinal prosthesis for visual stimulation. The system consists of a webcam, a notebook computer, and a prototype excitatory circuit. The system is driven by a MATLAB-based custom-built software. Live webcam images are converted to an 8 x 8 mosaic of 256 gray scale shades. Subsequently, electrical impulses are generated by the excitatory circuit in real-time to topographically stimulate the corresponding epiretinal cells. Following their conversion to gray scale, recorded data from the central pixel of the mosaic yielded: 36.24 nC for black, 48.48 nC for red, 55.68 nC for green, 67.68 nC for blue, and 91.92 nC for white. These results correlate well with data reported in the literature. The hallmark of this work is in the potential of partial restoration of sight that would add quality to the life of individuals with vision loss. PMID:18003325

  8. A web-based archive for topographic maps of retinal cell distribution in vertebrates.

    PubMed

    Collin, Shaun P

    2008-01-01

    Clinical and Experimental Optometry, in conjunction with Optometrists Association Australia and Professor Shaun P Collin of the University of Queensland, announce the launch of a web-based archive of previously published topographic maps of retinal cell distribution in vertebrates. At present, the archive boasts more than 770 different maps of the distribution of retinal neurons (for example, photoreceptors, bipolar cells, amacrine cells, horizontal cells and ganglion cells) in nearly 200 species within all vertebrate classes (Cephalospidomorpha, Actinopterygii, Sarcopterygii, Amphibia, Reptilia, Aves and Mammalia). The distribution of retinal neurons has been studied for more than 100 years and has become a powerful means of predicting the spatial resolving power of the eye and the retinal regions containing specialisations, such as areae centrales, horizontal streaks and foveae, where increased densities of neurons define the way in which a species visually samples its environment. The location of these retinal specialisations thereby identifies the part(s) of the visual field of critical importance for localising food and mates and for predator surveillance. The distribution of sampling elements even reflects the symmetry of a species' ecological habitat. The archive is a unique collection of most of the currently available retinal maps, which also presents relevant information, where known, about eye size, retinal cell density, retinal orientation, cell number, spatial resolving power and the type of specialisation, in addition to basic physical parameters of each species (body size, weight, sex and developmental stage). The archive is accessible at http://www.optometrists.asn.au/ceo/retinalsearch and will be updated regularly. The powerful database is interactive and freely available, providing the opportunity to upload both published and unpublished topographic maps. Following a review process, previously unpublished maps will be 'published' and available

  9. Progressive outer retinal necrosis syndrome: a comprehensive review of its clinical presentation, relationship to immune system status, and management.

    PubMed

    Austin

    2000-12-01

    Progressive outer retinal necrosis (PORN) syndrome is a form of the Varicella zoster virus (VZV) chorioretinitis found almost exclusively in people with the acquired immunodeficiency syndrome (AIDS). This destructive infection has an extremely rapid course that may lead to no light perception in affected eyes within days or weeks. Attempts at its treatment have had limited success. Rhegmatogenous retinal detachments often occur after the development of atrophic retinal holes, and silicone oil temponade has been found to be the most successful reattachment procedure. Unfortunately, cataract formation is common after such surgery. PORN needs to be differentiated from acute retinal necrosis (ARN) syndrome, a necrotizing retinitis that can also be caused by VZV. PORN and ARN are found at opposite ends of the spectrum of necrotizing herpetic retinopathies (NHR), where its clinical presentation depends upon immune system status. After a brief case presentation, the distinguishing clinical characteristics of PORN, its differentiation from ARN, attempts at its treatment, the role of the immune system status on its clinical appearance and treatment, and management of complications such as retinal detachment and subsequent cataracts are discussed.

  10. Age and diabetes related changes of the retinal capillaries: An ultrastructural and immunohistochemical study.

    PubMed

    Bianchi, Enrica; Ripandelli, Guido; Taurone, Samanta; Feher, Janos; Plateroti, Rocco; Kovacs, Illes; Magliulo, Giuseppe; Orlando, Maria Patrizia; Micera, Alessandra; Battaglione, Ezio; Artico, Marco

    2016-03-01

    Normal human aging and diabetes are associated with a gradual decrease of cerebral flow in the brain with changes in vascular architecture. Thickening of the capillary basement membrane and microvascular fibrosis are evident in the central nervous system of elderly and diabetic patients. Current findings assign a primary role to endothelial dysfunction as a cause of basement membrane (BM) thickening, while retinal alterations are considered to be a secondary cause of either ischemia or exudation. The aim of this study was to reveal any initial retinal alterations and variations in the BM of retinal capillaries during diabetes and aging as compared to healthy controls. Moreover, we investigated the potential role of vascular endothelial growth factor (VEGF) and pro-inflammatory cytokines in diabetic retina.Transmission electron microscopy (TEM) was performed on 46 enucleated human eyes with particular attention to alterations of the retinal capillary wall and Müller glial cells. Inflammatory cytokines expression in the retina was investigated by immunohistochemistry.Our electron microscopy findings demonstrated that thickening of the BM begins primarily at the level of the glial side of the retina during aging and diabetes. The Müller cells showed numerous cytoplasmic endosomes and highly electron-dense lysosomes which surrounded the retinal capillaries. Our study is the first to present morphological evidence that Müller cells start to deposit excessive BM material in retinal capillaries during aging and diabetes. Our results confirm the induction of pro-inflammatory cytokines TNF-α and IL-1β within the retina as a result of diabetes.These observations strongly suggest that inflammatory cytokines and changes in the metabolism of Müller glial cells rather than changes in of endothelial cells may play a primary role in the alteration of retinal capillaries BM during aging and diabetes. PMID:26604209

  11. A Novel Form of Progressive Retinal Atrophy in Swedish Vallhund Dogs

    PubMed Central

    Cooper, Ann E.; Ahonen, Saija; Rowlan, Jessica S.; Duncan, Alison; Seppälä, Eija H.; Vanhapelto, Päivi; Lohi, Hannes; Komáromy, András M.

    2014-01-01

    Inherited retinal degenerations, such as retinitis pigmentosa (RP) and age-related macular degeneration (AMD), represent leading causes of incurable blindness in humans. This is also true in dogs, where the term progressive retinal atrophy (PRA) is used to describe inherited photoreceptor degeneration resulting in progressive vision loss. Because of the similarities in ocular anatomy, including the presence of a cone photoreceptor-rich central retinal region, and the close genotype-phenotype correlation, canine models contribute significantly to the understanding of retinal disease mechanisms and the development of new therapies. The screening of the pure-bred dog population for new forms of PRA represents an important strategy to establish new large animal models. By examining 324 dogs of the Swedish vallhund breed in seven countries and across three continents, we were able to describe a new and unique form of PRA characterized by the multifocal appearance of red and brown discoloration of the tapetal fundus followed over time by thinning of the retina. We propose three stages of the disease based on the appearance of the ocular fundus and associated visual deficits. Electroretinography revealed a gradual loss of both rod and cone photoreceptor-mediated function in Stages 2 and 3 of the disease. In the few dogs that suffered from pronounced vision loss, night-blindness occurred first in late Stage 2, followed by decreased day-vision in Stage 3. Histologic examinations confirmed the loss of photoreceptor cells at Stage 3, which was associated with the accumulation of autofluorescent material in the adjacent retinal pigment epithelium. Pedigree analysis was suggestive of an autosomal-recessive mode of inheritance. Mutations in six known canine retinal degeneration genes as well as hypovitaminosis E were excluded as causes of the disease. The observed variability in the age of disease onset and rate of progression suggest the presence of genetic and/or environmental

  12. Spectral domain optical coherence tomography for early detection of retinal alterations in patients using hydroxychloroquine

    PubMed Central

    Ulviye, Yigit; Betul, Tugcu; Nur, Tarakcioglu Hatice; Selda, Celik

    2013-01-01

    Objective: To determine whether early toxic effects from hydroxychloroquine (HCQ) could be detected by spectral-domain optical coherence tomography (SD-OCT) before symtomatic visual loss occured. Materials and Methods: Fifteen subjects with a history of the chronic use of hydroxychloroquine monotherapy for less than five years without fundus changes (group 1) and 15 visually normal healthy subjects (group 2) were enrolled in this study. All participants underwent systemic and ocular examination, visual field testing, and macular scan imaging using SD-OCT. Results: There were no significant differences in sex and ages between the groups (P > 0.05). Mean duration of HCQ usage in group 1 was 2.5 ± 1.34 (range:1-5) years. Visual field testing with central 10-2 threshold program was normal in all subjects. Inner retinal thickness in parafoveal and perifoveal area were found to be significantly lower in group 1 compared to group 2 (P < 0.01 for perifoveal, P < 0.05 for parafoveal retinal measurements). However, significant thinning was demonstrated only in full retinal thickness of perifoveal area in group 1 compared to group 2 (P: 0.013). Parafoveal and perifoveal inner retinal thickness measurements of inferior quadrants were significantly reduced in group 1 compared to group 2 (P < 0.01). Conclusion: Significant thinning of inner retinal layer especially in parafoveal and perifoveal areas in the absence of clinical fundus changes was observed in our study. We consider that SD-OCT may determine when inner retinal thinning starts in these patients and may contribute a quantitative approach to the early diagnosis and progression of retinal changes. PMID:23685488

  13. Evaluation of Retinal Vessel Morphology in Patients with Parkinson's Disease Using Optical Coherence Tomography

    PubMed Central

    Hidding, Ute; Keserü, Matthias; Keserü, Diana; Hassenstein, Andrea; Stemplewitz, Birthe

    2016-01-01

    Purpose The retina has been found affected in Parkinson’s disease (PD). It is unclear if this is due to neurodegeneration of local dopamine-dependent retinal cells, a result of central nervous degeneration including the optic nerve or retinal small vessel disease. This study aimed to detect changes of the retinal vasculature in PD patients compared to controls. Methods We examined 49 PD patients and 49 age- and sex-matched healthy controls by spectral domain optical coherence tomography (SD-OCT) with a circular scan centred at the optic disc. Vessels within the retinal nerve fibre layer were identified by an automated algorithm and thereafter manually labelled as artery or vein. Layer segmentation, vessel lumen and direct surrounding tissue were marked automatically with a grey value and the contrast between both values in relation to the surrounding tissue was calculated. The differences in these grey value ratios among subjects were determined and used as an indicator for differences in vessel morphology. Furthermore, the diameters of the veins and arteries were measured and then compared between the groups. Results The contrast of retinal veins was significantly lower in PD patients compared to controls, which indicates changes in vessel morphology in PD. The contrast of arteries was not significantly different. Disease duration, disease stage according to Hoehn and Yahr or age did not influence the grey value ratios in PD patients. Vessel diameter in either veins or arteries did not differ between subject groups. The contrast of retinal veins contralateral to the clinically predominant and first affected side was significantly lower compared to the ipsilateral side. Conclusion Our data show a potential difference of the retinal vasculature in PD patients compared to controls. Vascular changes in the retina of PD patients might contribute to vision-related complaints in PD. PMID:27525728

  14. Honokiol inhibits pathological retinal neovascularization in oxygen-induced retinopathy mouse model

    SciTech Connect

    Vavilala, Divya Teja; O’Bryhim, Bliss E.; Ponnaluri, V.K. Chaithanya; White, R. Sid; Radel, Jeff; Symons, R.C. Andrew; Mukherji, Mridul

    2013-09-06

    Highlights: •Aberrant activation of HIF pathway is the underlying cause of ischemic neovascularization. •Honokiol has better therapeutic index as a HIF inhibitor than digoxin and doxorubicin. •Daily IP injection of honokiol in OIR mouse model reduced retinal neovascularization. •Honokiol also prevents vaso-obliteration, the characteristic feature of the OIR model. •Honokiol enhanced physiological revascularization of the retinal vascular plexuses. -- Abstract: Aberrant activation of the hypoxia inducible factor (HIF) pathway is the underlying cause of retinal neovascularization, one of the most common causes of blindness worldwide. The HIF pathway also plays critical roles during tumor angiogenesis and cancer stem cell transformation. We have recently shown that honokiol is a potent inhibitor of the HIF pathway in a number of cancer and retinal pigment epithelial cell lines. Here we evaluate the safety and efficacy of honokiol, digoxin, and doxorubicin, three recently identified HIF inhibitors from natural sources. Our studies show that honokiol has a better safety to efficacy profile as a HIF inhibitor than digoxin and doxorubicin. Further, we show for the first time that daily intraperitoneal injection of honokiol starting at postnatal day (P) 12 in an oxygen-induced retinopathy (OIR) mouse model significantly reduced retinal neovascularization at P17. Administration of honokiol also prevents the oxygen-induced central retinal vaso-obliteration, characteristic feature of the OIR model. Additionally, honokiol enhanced physiological revascularization of the retinal vascular plexuses. Since honokiol suppresses multiple pathways activated by HIF, in addition to the VEGF signaling, it may provide advantages over current treatments utilizing specific VEGF antagonists for ocular neovascular diseases and cancers.

  15. A novel form of progressive retinal atrophy in Swedish vallhund dogs.

    PubMed

    Cooper, Ann E; Ahonen, Saija; Rowlan, Jessica S; Duncan, Alison; Seppälä, Eija H; Vanhapelto, Päivi; Lohi, Hannes; Komáromy, András M

    2014-01-01

    Inherited retinal degenerations, such as retinitis pigmentosa (RP) and age-related macular degeneration (AMD), represent leading causes of incurable blindness in humans. This is also true in dogs, where the term progressive retinal atrophy (PRA) is used to describe inherited photoreceptor degeneration resulting in progressive vision loss. Because of the similarities in ocular anatomy, including the presence of a cone photoreceptor-rich central retinal region, and the close genotype-phenotype correlation, canine models contribute significantly to the understanding of retinal disease mechanisms and the development of new therapies. The screening of the pure-bred dog population for new forms of PRA represents an important strategy to establish new large animal models. By examining 324 dogs of the Swedish vallhund breed in seven countries and across three continents, we were able to describe a new and unique form of PRA characterized by the multifocal appearance of red and brown discoloration of the tapetal fundus followed over time by thinning of the retina. We propose three stages of the disease based on the appearance of the ocular fundus and associated visual deficits. Electroretinography revealed a gradual loss of both rod and cone photoreceptor-mediated function in Stages 2 and 3 of the disease. In the few dogs that suffered from pronounced vision loss, night-blindness occurred first in late Stage 2, followed by decreased day-vision in Stage 3. Histologic examinations confirmed the loss of photoreceptor cells at Stage 3, which was associated with the accumulation of autofluorescent material in the adjacent retinal pigment epithelium. Pedigree analysis was suggestive of an autosomal-recessive mode of inheritance. Mutations in six known canine retinal degeneration genes as well as hypovitaminosis E were excluded as causes of the disease. The observed variability in the age of disease onset and rate of progression suggest the presence of genetic and/or environmental

  16. Cell Therapy Applications for Retinal Vascular Diseases: Diabetic Retinopathy and Retinal Vein Occlusion.

    PubMed

    Park, Susanna S

    2016-04-01

    Retinal vascular conditions, such as diabetic retinopathy and retinal vein occlusion, remain leading causes of vision loss. No therapy exists to restore vision loss resulting from retinal ischemia and associated retinal degeneration. Tissue regeneration is possible with cell therapy. The goal would be to restore or replace the damaged retinal vasculature and the retinal neurons that are damaged and/or degenerating from the hypoxic insult. Currently, various adult cell therapies have been explored as potential treatment. They include mesenchymal stem cells, vascular precursor cells (i.e., CD34+ cells, hematopoietic cells or endothelial progenitor cells), and adipose stromal cells. Preclinical studies show that all these cells have a paracrine trophic effect on damaged ischemic tissue, leading to tissue preservation. Endothelial progenitor cells and adipose stromal cells integrate into the damaged retinal vascular wall in preclinical models of diabetic retinopathy and ischemia-reperfusion injury. Mesenchymal stem cells do not integrate as readily but appear to have a primary paracrine trophic effect. Early phase clinical trials have been initiated and ongoing using mesenchymal stem cells or autologous bone marrow CD34+ cells injected intravitreally as potential therapy for diabetic retinopathy or retinal vein occlusion. Adipose stromal cells or pluripotent stem cells differentiated into endothelial colony-forming cells have been explored in preclinical studies and show promise as possible therapies for retinal vascular disorders. The relative safety or efficacy of these various cell therapies for treating retinal vascular disorders have yet to be determined.

  17. Advancing therapeutic strategies for inherited retinal degeneration: recommendations from the Monaciano Symposium.

    PubMed

    Thompson, Debra A; Ali, Robin R; Banin, Eyal; Branham, Kari E; Flannery, John G; Gamm, David M; Hauswirth, William W; Heckenlively, John R; Iannaccone, Alessandro; Jayasundera, K Thiran; Khan, Naheed W; Molday, Robert S; Pennesi, Mark E; Reh, Thomas A; Weleber, Richard G; Zacks, David N

    2015-02-09

    Although rare in the general population, retinal dystrophies occupy a central position in current efforts to develop innovative therapies for blinding diseases. This status derives, in part, from the unique biology, accessibility, and function of the retina, as well as from the synergy between molecular discoveries and transformative advances in functional assessment and retinal imaging. The combination of these factors has fueled remarkable progress in the field, while at the same time creating complex challenges for organizing collective efforts aimed at advancing translational research. The present position paper outlines recent progress in gene therapy and cell therapy for this group of disorders, and presents a set of recommendations for addressing the challenges remaining for the coming decade. It is hoped that the formulation of these recommendations will stimulate discussions among researchers, funding agencies, industry, and policy makers that will accelerate the development of safe and effective treatments for retinal dystrophies and related diseases.

  18. Line-field parallel swept source MHz OCT for structural and functional retinal imaging

    PubMed Central

    Fechtig, Daniel J.; Grajciar, Branislav; Schmoll, Tilman; Blatter, Cedric; Werkmeister, Rene M.; Drexler, Wolfgang; Leitgeb, Rainer A.

    2015-01-01

    We demonstrate three-dimensional structural and functional retinal imaging with line-field parallel swept source imaging (LPSI) at acquisition speeds of up to 1 MHz equivalent A-scan rate with sensitivity better than 93.5 dB at a central wavelength of 840 nm. The results demonstrate competitive sensitivity, speed, image contrast and penetration depth when compared to conventional point scanning OCT. LPSI allows high-speed retinal imaging of function and morphology with commercially available components. We further demonstrate a method that mitigates the effect of the lateral Gaussian intensity distribution across the line focus and demonstrate and discuss the feasibility of high-speed optical angiography for visualization of the retinal microcirculation. PMID:25798298

  19. Advancing Therapeutic Strategies for Inherited Retinal Degeneration: Recommendations From the Monaciano Symposium

    PubMed Central

    Thompson, Debra A.; Ali, Robin R.; Banin, Eyal; Branham, Kari E.; Flannery, John G.; Gamm, David M.; Hauswirth, William W.; Heckenlively, John R.; Iannaccone, Alessandro; Jayasundera, K. Thiran; Khan, Naheed W.; Molday, Robert S.; Pennesi, Mark E.; Reh, Thomas A.; Weleber, Richard G.; Zacks, David N.

    2015-01-01

    Although rare in the general population, retinal dystrophies occupy a central position in current efforts to develop innovative therapies for blinding diseases. This status derives, in part, from the unique biology, accessibility, and function of the retina, as well as from the synergy between molecular discoveries and transformative advances in functional assessment and retinal imaging. The combination of these factors has fueled remarkable progress in the field, while at the same time creating complex challenges for organizing collective efforts aimed at advancing translational research. The present position paper outlines recent progress in gene therapy and cell therapy for this group of disorders, and presents a set of recommendations for addressing the challenges remaining for the coming decade. It is hoped that the formulation of these recommendations will stimulate discussions among researchers, funding agencies, industry, and policy makers that will accelerate the development of safe and effective treatments for retinal dystrophies and related diseases. PMID:25667399

  20. Fixation strategies for retinal immunohistochemistry.

    PubMed

    Stradleigh, Tyler W; Ishida, Andrew T

    2015-09-01

    Immunohistochemical and ex vivo anatomical studies have provided many glimpses of the variety, distribution, and signaling components of vertebrate retinal neurons. The beauty of numerous images published to date, and the qualitative and quantitative information they provide, indicate that these approaches are fundamentally useful. However, obtaining these images entailed tissue handling and exposure to chemical solutions that differ from normal extracellular fluid in composition, temperature, and osmolarity. Because the differences are large enough to alter intercellular and intracellular signaling in neurons, and because retinae are susceptible to crush, shear, and fray, it is natural to wonder if immunohistochemical and anatomical methods disturb or damage the cells they are designed to examine. Tissue fixation is typically incorporated to guard against this damage and is therefore critically important to the quality and significance of the harvested data. Here, we describe mechanisms of fixation; advantages and disadvantages of using formaldehyde and glutaraldehyde as fixatives during immunohistochemistry; and modifications of widely used protocols that have recently been found to improve cell shape preservation and immunostaining patterns, especially in proximal retinal neurons. PMID:25892361

  1. Measurement of retinal blood velocity

    NASA Astrophysics Data System (ADS)

    Winchester, Leonard W., Jr.; Chou, Nee-Yin

    2006-02-01

    A fundus camera was modified to illuminate the retina of a rabbit model with low power laser light in order to obtain laser speckle images. A fast-exposure charge-coupled device (CCD) camera was used to capture laser speckle images of the retina. Image acquisition was synchronized with the arterial pulses of the rabbit to ensure that all images are obtained at the same point in the cardiac cycle. The rabbits were sedated and a speculum was inserted to prevent the eyelid from closing. Both albino (New Zealand; pigmented (Dutch belted) rabbits were used in the study. The rabbit retina is almost avascular. The measurements are obtained for choroidal tissue as well as retinal tissue. Because the retina is in a region of high metabolism, blood velocity is strongly affected by blood oxygen saturation. Measurements of blood velocity obtained over a wide range of O II saturations (58%-100%) showed that blood velocity increases with decreasing O II saturation. For most experiments, the left eye of the rabbit was used for laser measurements whereas the right eye served as a control. No observable difference between pre- and post-experimented eye was noted. Histological examinations of retinal tissue subjected to repeated laser measurements showed no indication of tissue damage.

  2. Fixation Strategies For Retinal Immunohistochemistry

    PubMed Central

    Stradleigh, Tyler W.; Ishida, Andrew T.

    2015-01-01

    Immunohistochemical and ex vivo anatomical studies have provided many glimpses of the variety, distribution, and signaling components of vertebrate retinal neurons. The beauty of numerous images published to date, and the qualitative and quantitative information they provide, indicate that these approaches are fundamentally useful. However, obtaining these images entailed tissue handling and exposure to chemical solutions that differ from normal extracellular fluid in composition, temperature, and osmolarity. Because the differences are large enough to alter intercellular and intracellular signaling in neurons, and because retinae are susceptible to crush, shear, and fray, it is natural to wonder if immunohistochemical and anatomical methods disturb or damage the cells they are designed to examine. Tissue fixation is typically incorporated to guard against this damage and is therefore critically important to the quality and significance of the harvested data. Here, we describe mechanisms of fixation; advantages and disadvantages of using formaldehyde and glutaraldehyde as fixatives during immunohistochemistry; and modifications of widely used protocols that have recently been found to improve cell shape preservation and immunostaining patterns, especially in proximal retinal neurons. PMID:25892361

  3. Microperimetry of localized retinal nerve fiber layer defects.

    PubMed

    Orzalesi, N; Miglior, S; Lonati, C; Rosetti, L

    1998-03-01

    The aim of this study was to determine the sensitivity of retinal areas involved in a localized retinal nerve fiber layer (RNFL) defect and to assess correlations between microperimetry and the standard full threshold central 30 deg visual field test. Twenty-five patients with focal RNFL defects, evaluated by means of Argon-blue scanning laser ophthalmoscopy (SLO), underwent an automated 30 deg central visual field examination and a microperimetry with SLO. Microperimetry was performed according to standard procedures (infrared laser for fundus imaging; HeNe laser for 10 candles/m2 background illumination, fixation aid and generation of stimuli; manual fundus tracking). The size of stimuli was Goldmann III with 0.1 sec duration. In eyes with focal RNFL defects a deep microperimetric scotoma of at least 5 dB was found in 12 cases and a mild scotoma (1-4 dB) in 13 cases. These scotomas were mainly located throughout the whole defect or grouped in the temporal or nasal sides of the defect and were characterized by sharp and well-defined borders. With automated perimetry, a scotoma, defined by a single point depression of at least 10 dB or a depression of at least 5 dB in two or more contiguous points corresponding to the RNFL, defect, was found in only 14 out of 25 eyes with microperimetric defect. Focal RNFL defects correspond to localized areas of depressed retinal sensitivity as evaluated by microperimetry. The close correspondence between structural and microperimetric findings suggests that, in hypertensive eyes also, localized RNFL defects correspond to visual dysfunction possibly associated with substantial atrophy of ganglion cells. PMID:9604104

  4. Genetic linkage studies in autosomal recessive retinitis pigmentosa

    SciTech Connect

    Mansfield, D.C.; Teague, P.W.; Barber, A.

    1994-09-01

    Autosomal recessive retinitis pigmentosa (arRP) is a severe retinal dystrophy characterized by night blindness, progressive constriction of the visual fields and loss of central vision in the fourth or fifth decades. The frequency of this form of retinitis pigmentosa (RP) varies in different populations. Mutations within the rhodopsin, cyclic GMP phosphodiesterase-{beta} subunit and cGMP-gated channel genes have been reported in some arRP families. The genetic loci responsible for the majority of cases have yet to be identified. Genetic heterogeneity is likely to be extensive. In order to minimize the amount of genetic heterogenity, a set of arRP families was ascertained within the South-Central Sardinian population, in which 81% of families with a known mode of inheritance show an autosomal recessive form of RP. The Sardinian population is an ethnic {open_quotes}outlier{close_quotes}, having remained relatively isolated from mainland and other cultures. Genetic linkage data has been obtained in a set of 11 Sardinian arRP kindreds containing 26 affected members. Under the assumption of genetic homogeneity, no evidence of linkage was found in the arRP kindreds using 195 markers, which excluded 62% of the genome (Z<-2). Positive lod scores were obtained with D14S80 which showed no recombination in a subset of 5 families. Heterogeneity testing using D14S80 and arRP showed no significant evidence of heterogeneity (p=0.18) but evidence of linkage ({chi}{sup 2}=3.64, p=0.028). We are currently screening the neural retina-specific leucine zipper gene (NRL) in 14q11 for mutations as a candidate locus.

  5. Neural remodeling in retinal degeneration.

    PubMed

    Marc, Robert E; Jones, Bryan W; Watt, Carl B; Strettoi, Enrica

    2003-09-01

    Mammalian retinal degenerations initiated by gene defects in rods, cones or the retinal pigmented epithelium (RPE) often trigger loss of the sensory retina, effectively leaving the neural retina deafferented. The neural retina responds to this challenge by remodeling, first by subtle changes in neuronal structure and later by large-scale reorganization. Retinal degenerations in the mammalian retina generally progress through three phases. Phase 1 initiates with expression of a primary insult, followed by phase 2 photoreceptor death that ablates the sensory retina via initial photoreceptor stress, phenotype deconstruction, irreversible stress and cell death, including bystander effects or loss of trophic support. The loss of cones heralds phase 3: a protracted period of global remodeling of the remnant neural retina. Remodeling resembles the responses of many CNS assemblies to deafferentation or trauma, and includes neuronal cell death, neuronal and glial migration, elaboration of new neurites and synapses, rewiring of retinal circuits, glial hypertrophy and the evolution of a fibrotic glial seal that isolates the remnant neural retina from the surviving RPE and choroid. In early phase 2, stressed photoreceptors sprout anomalous neurites that often reach the inner plexiform and ganglion cell layers. As death of rods and cones progresses, bipolar and horizontal cells are deafferented and retract most of their dendrites. Horizontal cells develop anomalous axonal processes and dendritic stalks that enter the inner plexiform layer. Dendrite truncation in rod bipolar cells is accompanied by revision of their macromolecular phenotype, including the loss of functioning mGluR6 transduction. After ablation of the sensory retina, Müller cells increase intermediate filament synthesis, forming a dense fibrotic layer in the remnant subretinal space. This layer invests the remnant retina and seals it from access via the choroidal route. Evidence of bipolar cell death begins in

  6. Persistent inflammatory state after photoreceptor loss in an animal model of retinal degeneration

    PubMed Central

    Noailles, Agustina; Maneu, Victoria; Campello, Laura; Gómez-Vicente, Violeta; Lax, Pedro; Cuenca, Nicolás

    2016-01-01

    Microglia act as the resident immune cells of the central nervous system, including the retina. In response to damaging stimuli microglia adopt an activated state, which can progress into a phagocytic phenotype and play a potentially harmful role by eliciting the expression and release of pro-inflammatory cytokines. The aim of the present study was to assess longitudinal changes in microglia during retinal degeneration in the homozygous P23H rat, a model of dominant retinitis pigmentosa. Microglial phenotypes, morphology and density were analyzed by immunohistochemistry, flow cytometry, and cytokine antibody array. In addition, we performed electroretinograms to evaluate the retinal response. In the P23H retina, sclera, choroid and ciliary body, inflammatory cells increased in number compared with the control at all ages analyzed. As the rats became older, a higher number of amoeboid MHC-II+ cells were observed in the P23H retina, which correlated with an increase in the expression of pro-inflammatory cytokines. These findings suggest that, in the P23H model, retinal neuroinflammation persists throughout the rat’s life span even after photoreceptor depletion. Therefore, the inclusion of anti-inflammatory drugs at advanced stages of the neurodegenerative process may provide better retinal fitness so the remaining cells could still be used as targets of cellular or gene therapies. PMID:27624537

  7. Persistent inflammatory state after photoreceptor loss in an animal model of retinal degeneration.

    PubMed

    Noailles, Agustina; Maneu, Victoria; Campello, Laura; Gómez-Vicente, Violeta; Lax, Pedro; Cuenca, Nicolás

    2016-01-01

    Microglia act as the resident immune cells of the central nervous system, including the retina. In response to damaging stimuli microglia adopt an activated state, which can progress into a phagocytic phenotype and play a potentially harmful role by eliciting the expression and release of pro-inflammatory cytokines. The aim of the present study was to assess longitudinal changes in microglia during retinal degeneration in the homozygous P23H rat, a model of dominant retinitis pigmentosa. Microglial phenotypes, morphology and density were analyzed by immunohistochemistry, flow cytometry, and cytokine antibody array. In addition, we performed electroretinograms to evaluate the retinal response. In the P23H retina, sclera, choroid and ciliary body, inflammatory cells increased in number compared with the control at all ages analyzed. As the rats became older, a higher number of amoeboid MHC-II(+) cells were observed in the P23H retina, which correlated with an increase in the expression of pro-inflammatory cytokines. These findings suggest that, in the P23H model, retinal neuroinflammation persists throughout the rat's life span even after photoreceptor depletion. Therefore, the inclusion of anti-inflammatory drugs at advanced stages of the neurodegenerative process may provide better retinal fitness so the remaining cells could still be used as targets of cellular or gene therapies. PMID:27624537

  8. Persistent inflammatory state after photoreceptor loss in an animal model of retinal degeneration.

    PubMed

    Noailles, Agustina; Maneu, Victoria; Campello, Laura; Gómez-Vicente, Violeta; Lax, Pedro; Cuenca, Nicolás

    2016-09-14

    Microglia act as the resident immune cells of the central nervous system, including the retina. In response to damaging stimuli microglia adopt an activated state, which can progress into a phagocytic phenotype and play a potentially harmful role by eliciting the expression and release of pro-inflammatory cytokines. The aim of the present study was to assess longitudinal changes in microglia during retinal degeneration in the homozygous P23H rat, a model of dominant retinitis pigmentosa. Microglial phenotypes, morphology and density were analyzed by immunohistochemistry, flow cytometry, and cytokine antibody array. In addition, we performed electroretinograms to evaluate the retinal response. In the P23H retina, sclera, choroid and ciliary body, inflammatory cells increased in number compared with the control at all ages analyzed. As the rats became older, a higher number of amoeboid MHC-II(+) cells were observed in the P23H retina, which correlated with an increase in the expression of pro-inflammatory cytokines. These findings suggest that, in the P23H model, retinal neuroinflammation persists throughout the rat's life span even after photoreceptor depletion. Therefore, the inclusion of anti-inflammatory drugs at advanced stages of the neurodegenerative process may provide better retinal fitness so the remaining cells could still be used as targets of cellular or gene therapies.

  9. Relation of Blood Pressure to Retinal Vessel Diameter in Type 1 Diabetes Mellitus

    PubMed Central

    Klein, Ronald; Myers, Chelsea E.; Klein, Barbara E. K.; Zinman, Bernard; Gardiner, Robert; Suissa, Samy; Sinaiko, Alan R.; Donnelly, Sandra M.; Goodyer, Paul; Strand, Trudy; Mauer, Michael

    2009-01-01

    Objective To examine the relationship of blood pressure (BP) and use of angiotensin receptor blocker (ARB) or angiotensin converting enzyme inhibitor (ACEI) to retinal vessel diameter in normotensive, normoalbuminuric persons with type 1 diabetes mellitus (T1DM). Design Randomized controlled clinical trial. Participants Persons with T1DM and gradable fundus photographs both at baseline (n=147) and 5-year follow-up (n=124). Methods Clinic and 24-hour ambulatory BPs (ABP) were measured. Retinal arteriolar and venular diameters were measured using a computer-assisted technique. Individual arteriolar and venular measurements were combined into summary indices that reflect the average retinal arteriolar (central retinal arteriolar equivalent [CRAE]) and venular (central retinal venular equivalent [CRVE]) diameter of an eye, respectively. Main Outcome Measures CRAE and CRVE. Results While controlling for age, study site, glycosylated hemoglobin and ambulatory pulse rate, daytime ambulatory systolic (-0.29 μm effect per 1mmHg, P=.02) and daytime ambulatory diastolic (-0.44 μm effect per 1mmHg, P=.04), nighttime ambulatory systolic (-0.27 μm effect per 1mmHg, P=.03), and 24-hour ambulatory systolic BP (-0.31 μm effect per 1mmHg, P=.03) were cross-sectionally associated with a smaller CRAE. While controlling for age, study site, glycosylated hemoglobin, ambulatory pulse rate and baseline CRAE, no BP measure was associated with a change in CRAE or CRVE over 5 years of follow-up. Treatment with losartan or enalapril was not associated with a statistically significant change in CRAE or CRVE. Conclusions ACEI or ARB therapy does not affect retinal arteriolar or venular diameter in normotensive persons with T1DM. PMID:20142543

  10. Assessment of blood-retinal barrier integrity.

    PubMed

    Vinores, S A

    1995-01-01

    The blood-retinal barrier consists of two components which are comprised of the retinal vascular endothelium and the retinal pigment epithelium, respectively. Its functional integrity can be recognized by tight junctions between these cells with a paucity of endocytic vesicles within them and the presence of the molecules that regulate the ionic and metabolic gradients that constitute the barrier. The barrier is compromised in several disease processes and by a variety of agents, but in most cases the location and mechanism for barrier failure is not understood. Perfusion with a variety of radiolabeled tracer molecules, vitreous fluorophotometry, or magnetic resonance imaging can be used to quantitate blood-retinal barrier leakage. Fluorescein angiography or magnetic resonance imaging can localize sites of leakage in vivo with limited resolution. Evans blue dye can be used to visualize blood-retinal barrier failure in gross pathological specimens and immuno-histochemical labeling of serum proteins such as albumin or fibrinogen can be used to localize sites of blood-retinal barrier breakdown by light microscopy. Tracers such as horseradish peroxidase, microperoxidase, or lanthanum, or the immunocytochemical demonstration of albumin can be used to reveal blood-retinal barrier breakdown at the ultrastructural level and provide insights into the mechanisms involved. This review discusses the advantages and limitations of each of these methods to aid in selection of the appropriate techniques to derive the desired information.

  11. A mechanical model of retinal detachment

    NASA Astrophysics Data System (ADS)

    Chou, Tom; Siegel, Michael

    2012-08-01

    We present a model of the mechanical and fluid forces associated with exudative retinal detachments where the retinal photoreceptor cells separate, typically from the underlying retinal pigment epithelium (RPE). By computing the total fluid volume flow arising from transretinal, vascular and RPE pump currents, we determine the conditions under which the subretinal fluid pressure exceeds the maximum yield stress holding the retina and RPE together, giving rise to an irreversible, extended retinal delamination. We also investigate localized, blister-like retinal detachments by balancing mechanical tension in the retina with both the retina-RPE adhesion energy and the hydraulic pressure jump across the retina. For detachments induced by traction forces, we find a critical radius beyond which the blister is unstable to growth. Growth of a detached blister can also be driven by inflamed lesions in which the tissue has a higher choroidal hydraulic conductivity, has insufficient RPE pump activity, or has defective adhesion bonds. We determine the parameter regimes in which the blister either becomes unstable to growth, remains stable and finite-sized, or shrinks, allowing possible healing. The corresponding stable blister radius and shape are calculated. Our analysis provides a quantitative description of the physical mechanisms involved in exudative retinal detachments and can help guide the development of retinal reattachment protocols or preventative procedures.

  12. Optical Coherence Tomography Angiography in Retinal Diseases

    PubMed Central

    Chalam, K. V.; Sambhav, Kumar

    2016-01-01

    Optical coherence tomography angiography (OCTA) is a new, non-invasive imaging system that generates volumetric data of retinal and choroidal layers. It has the ability to show both structural and blood flow information. Split-spectrum amplitude-decorrelation angiography (SSADA) algorithm (a vital component of OCTA software) helps to decrease the signal to noise ratio of flow detection thus enhancing visualization of retinal vasculature using motion contrast. Published studies describe potential efficacy for OCTA in the evaluation of common ophthalmologic diseases such as diabetic retinopathy, age related macular degeneration (AMD), retinal vascular occlusions and sickle cell disease. OCTA provides a detailed view of the retinal vasculature, which allows accurate delineation of microvascular abnormalities in diabetic eyes and vascular occlusions. It helps quantify vascular compromise depending upon the severity of diabetic retinopathy. OCTA can also elucidate the presence of choroidal neovascularization (CNV) in wet AMD. In this paper, we review the knowledge, available in English language publications regarding OCTA, and compare it with the conventional angiographic standard, fluorescein angiography (FA). Finally, we summarize its potential applications to retinal vascular diseases. Its current limitations include a relatively small field of view, inability to show leakage, and tendency for image artifacts. Further larger studies will define OCTA's utility in clinical settings and establish if the technology may offer a non-invasive option of visualizing the retinal vasculature, enabling us to decrease morbidity through early detection and intervention in retinal diseases. PMID:27195091

  13. Optical Coherence Tomography Angiography in Retinal Diseases.

    PubMed

    Chalam, K V; Sambhav, Kumar

    2016-01-01

    Optical coherence tomography angiography (OCTA) is a new, non-invasive imaging system that generates volumetric data of retinal and choroidal layers. It has the ability to show both structural and blood flow information. Split-spectrum amplitude-decorrelation angiography (SSADA) algorithm (a vital component of OCTA software) helps to decrease the signal to noise ratio of flow detection thus enhancing visualization of retinal vasculature using motion contrast. Published studies describe potential efficacy for OCTA in the evaluation of common ophthalmologic diseases such as diabetic retinopathy, age related macular degeneration (AMD), retinal vascular occlusions and sickle cell disease. OCTA provides a detailed view of the retinal vasculature, which allows accurate delineation of microvascular abnormalities in diabetic eyes and vascular occlusions. It helps quantify vascular compromise depending upon the severity of diabetic retinopathy. OCTA can also elucidate the presence of choroidal neovascularization (CNV) in wet AMD. In this paper, we review the knowledge, available in English language publications regarding OCTA, and compare it with the conventional angiographic standard, fluorescein angiography (FA). Finally, we summarize its potential applications to retinal vascular diseases. Its current limitations include a relatively small field of view, inability to show leakage, and tendency for image artifacts. Further larger studies will define OCTA's utility in clinical settings and establish if the technology may offer a non-invasive option of visualizing the retinal vasculature, enabling us to decrease morbidity through early detection and intervention in retinal diseases.

  14. Effects of central activation of serotonin 5-HT2A/2C or dopamine D2/3 receptors on the acute and repeated effects of clozapine in the conditioned avoidance response test

    PubMed Central

    Feng, Min; Gao, Jun; Sui, Nan; Li, Ming

    2014-01-01

    Rationale: Acute administration of clozapine (a gold standard of atypical antipsychotics) disrupts avoidance response in rodents, while repeated administration often causes a tolerance effect. Objective: The present study investigated the neuroanatomical basis and receptor mechanisms of acute and repeated effects of clozapine treatment in the conditioned avoidance response test in male Sprague-Dawley rats. Methods: DOI (2,5-dimethoxy-4-iodo-amphetamine, a preferential 5-HT2A/2C agonist) or quinpirole (a preferential dopamine D2/3 agonist) was microinjected into the medial prefrontal cortex (mPFC) or nucleus accumbens shell (NAs), and their effects on the acute and long-term avoidance-disruptive effect of clozapine were tested. Results: Intra-mPFC microinjection of quinpirole enhanced the acute avoidance disruptive effect of clozapine (10 mg/kg, sc), while DOI microinjections reduced it marginally. Repeated administration of clozapine (10 mg/kg, sc) daily for 5 days caused a progressive decrease in its inhibition of avoidance responding, indicating tolerance development. Intra-mPFC microinjection of DOI at 25.0 (but not 5.0) μg/side during this period completely abolished the expression of clozapine tolerance. This was indicated by the finding that clozapine-treated rats centrally infused with 25.0 μg/side DOI did not show higher levels of avoidance responses than the vehicle-treated rats in the clozapine challenge test. Microinjection of DOI into the mPFC immediately before the challenge test also decreased the expression of clozapine tolerance. Conclusions: Acute behavioral effect of clozapine can be enhanced by activation of the D2/3 receptors in the mPFC. Clozapine tolerance expression relies on the neuroplasticity initiated by its antagonist action against 5-HT2A/2C receptors in the mPFC. PMID:25288514

  15. Suitability of UK Biobank Retinal Images for Automatic Analysis of Morphometric Properties of the Vasculature

    PubMed Central

    MacGillivray, Thomas J; Cameron, James R.; Zhang, Qiuli; El-Medany, Ahmed; Mulholland, Carl; Sheng, Ziyan; Dhillon, Bal; Doubal, Fergus N.; Foster, Paul J.

    2015-01-01

    Purpose To assess the suitability of retinal images held in the UK Biobank - the largest retinal data repository in a prospective population-based cohort - for computer assisted vascular morphometry, generating measures that are commonly investigated as candidate biomarkers of systemic disease. Methods Non-mydriatic fundus images from both eyes of 2,690 participants - people with a self-reported history of myocardial infarction (n=1,345) and a matched control group (n=1,345) - were analysed using VAMPIRE software. These images were drawn from those of 68,554 UK Biobank participants who underwent retinal imaging at recruitment. Four operators were trained in the use of the software to measure retinal vascular tortuosity and bifurcation geometry. Results Total operator time was approximately 360 hours (4 minutes per image). 2,252 (84%) of participants had at least one image of sufficient quality for the software to process, i.e. there was sufficient detection of retinal vessels in the image by the software to attempt the measurement of the target parameters. 1,604 (60%) of participants had an image of at least one eye that was adequately analysed by the software, i.e. the measurement protocol was successfully completed. Increasing age was associated with a reduced proportion of images that could be processed (p=0.0004) and analysed (p<0.0001). Cases exhibited more acute arteriolar branching angles (p=0.02) as well as lower arteriolar and venular tortuosity (p<0.0001). Conclusions A proportion of the retinal images in UK Biobank are of insufficient quality for automated analysis. However, the large size of the UK Biobank means that tens of thousands of images are available and suitable for computational analysis. Parametric information measured from the retinas of participants with suspected cardiovascular disease was significantly different to that measured from a matched control group. PMID:26000792

  16. Retinal venous pressure: the role of endothelin.

    PubMed

    Flammer, Josef; Konieczka, Katarzyna

    2015-01-01

    The retinal venous pressure (RVP) can be measured non-invasively. While RVP is equal to or slightly above intraocular pressure (IOP) in healthy people, it is often markedly increased in patients with eye or systemic diseases. Beside a mechanical obstruction, the main cause of such an elevation is a local dysregulation of a retinal vein, particularly a constriction induced by endothelin-1 (ET-1). A local increase of ET-1 can result from a high plasma level, as ET-1 can diffuse from the fenestrated capillaries of the choroid into the optic nerve head (ONH), bypassing the blood retinal barrier. A local increase can also result from increased local production either by a sick neighboring artery or retinal tissue. Generally, the main factors increasing ET-1 are inflammations and hypoxia, either locally or in a remote organ. RVP is known to be increased in patients with glaucoma, retinal vein occlusion (RVO), diabetic retinopathy, high mountain disease, and primary vascular dysregulation (PVD). PVD is the major vascular component of Flammer syndrome (FS). An increase of RVP decreases perfusion pressure, which heightens the risk for hypoxia. An increase of RVP also elevates transmural pressure, which in turn heightens the risk for retinal edema. In patients with RVO, a high level of RVP may not only be a consequence but also a potential cause of the occlusion; therefore, it risks causing a vicious circle. Narrow retinal arteries and particularly dilated retinal veins are known risk indicators for future cardiovascular events. As the major cause for such a retinal venous dilatation is an increased RVP, RVP may likely turn out to be an even stronger predictor. PMID:26504500

  17. Aging Changes in Retinal Microglia and their Relevance to Age-related Retinal Disease.

    PubMed

    Ma, Wenxin; Wong, Wai T

    2016-01-01

    Age-related retinal diseases, such as age-related macular degeneration (AMD) and glaucoma, contain features of chronic retinal inflammation that may promote disease progression. However, the relationship between aging and neuroinflammation is unclear. Microglia are long-lived, resident immune cells of the retina, and mediate local neuroinflammatory reactions. We hypothesize that aging changes in microglia may be causally linked to neuroinflammatory changes underlying age-dependent retinal diseases. Here, we review the evidence for (1) how the retinal microglial phenotype changes with aging, (2) the factors that drive microglial aging in the retina, and (3) aging-related changes in microglial gene expression. We examine how these aspects of microglial aging changes may relate to pathogenic mechanisms of immune dysregulation driving the progression of age-related retinal disease. These relationships can highlight microglial aging as a novel target for the prevention and treatment of retinal disease.

  18. Retinoids for Treatment of Retinal Diseases

    PubMed Central

    Palczewski, Krzysztof

    2010-01-01

    Knowledge about retinal photoreceptor signal transduction and the visual cycle required for normal eyesight has expanded exponentially over the past decade. Substantial progress in human genetics has allowed identification of candidate genes and complex networks underlying inherited retinal diseases. Natural mutations in animal models that mimic human diseases have been characterized and advanced genetic manipulation now permits generation of small mammalian models of human retinal diseases. Pharmacological repair of defective visual processes in animal models not only validates their involvement in vision but also provides great promise for developing improved therapies for the millions that are progressing towards blindness or are almost completely robbed of eyesight. PMID:20435355

  19. Fluid vitreous substitutes in vitreo retinal surgery.

    PubMed

    Saxena, S; Gopal, L

    1996-12-01

    Advances in the surgical instrumentation and vitreoretinal techniques have allowed intraoperative reapproximation of retina to a more normal position. The use of intravitreally injected liquid materials (viscoelastic liquids, liquid perfluorocarbons and silicone oil), as adjunctive agents to vitreo-retinal surgery play an important role in facilitating retinal reattachment. These materials are used as intraoperative instruments to re-establish intraocular volume, assist in separating membranes adherent to the retina, manipulate retinal detachments and mechanically flatten detached retina. Over the longer term, silicone oil maintains intraocular tamponade. One should be cognizant of the potential uses, benefits and risks of each of these vitreous substitutes.

  20. [New drug therapy for retinal degeneration].

    PubMed

    Ohguro, Hiroshi

    2008-01-01

    Retinitis pigmentosa (RP) is an inherited retinal degeneration characterized by nyctalopia, ring scotoma, and bone-spicule pigmentation of the retina. So far, no effective therapy has been found for RP. As a possible molecular etiology of RP, retina-specific gene deficits are most likely involved, but little has been identified in terms of intracellular mechanisms leading to retinal photoreceptor cell death at post-translational levels. In order to find an effective therapy for RP, we must look for underlying common mechanisms that are responsible for the development of RP, instead of designing a specific therapy for each of the RP types with different causes. Therefore, in the present study, several animal models with different causes of RP were studied, including (1)Royal College of Surgeons (RCS) rats with a deficit of retinal pigment epithelium (RPE) function caused by rhodopsin mutation; (2) P23H rats, (3) S334ter rats, (4) photo stress rats, (5) retinal degeneration (rd) mice with a deficit of phosphodiesterase(PDE) function; and (6) cancer-associated retinopathy (CAR) model rats with a deficit of recoverin-dependent photoreceptor adaptation function. In each of these models, the following assessments were made in order to elucidate common pathological mechanisms among the models: (1) retinal function assessed by electroretinogram (ERG), (2) retinal morphology, (3) retinoid analysis, (4) rhodopsin regeneration, (5) rhodopsin phosphorylation and dephosphorylation, and (6) cytosolic cGMP levels. We found that unregulated photoreceptor adaptation processes caused by an imbalance of rhodopsin phosphorylation and dephosphorylation caused retinal dysfunction leading to photoreceptor cell death. As possible candidate drugs for normalizing these retinal dysfunctions and stopping further retinal degeneration, nilvadipine, a Ca channel blocker, retinoid derivatives, and anthocyanine were chosen and tested to determine their effect on the above animal models with

  1. Evaluation of the effectiveness and safety of glucocorticoids intravitreal implant therapy in macular edema due to retinal vein occlusion.

    PubMed

    Michalska-Małecka, Katarzyna; Gaborek, Aneta; Nowak, Mariusz; Halat, Tomasz; Pawłowska, Mariola; Śpiewak, Dorota

    2016-01-01

    The purpose of this study was to evaluate the impact of intravitreal dexamethasone implant (Ozurdex) on macular morphology and functions in eyes with macular edema (ME) secondary to retinal vein occlusion. Efficacy outcomes of the treatment were best-corrected visual acuity (BCVA) and central retinal thickness (CRT). Safety outcomes were intraocular pressure and cornea endothelial cell density. The study was conducted by the prospective analysis on 36 patients (17 women and 19 men) aged 28-77 years (the average age was 58±15 years) treated with the injection of dexamethasone implant because of the persistent ME at the Department of Ophthalmology and Ophthalmology Outpatient Clinic of the University Centre of Ophthalmology and Oncology in Katowice. The studied group included 16 patients with central retinal vein occlusion (16 eyes), and 20 patients with branch retinal vein occlusion (20 eyes). We found a significant increase of BCVA after first, second, and third month of treatment. Six months after the treatment, BCVA decreased, although not significantly compared with the value obtained in the third month. Two months after the intravitreal implantation of dexamethasone delivery system, CRT was 338±163 μm and was significantly lower compared with pretreatment value. Between third and sixth month after the treatment, we found insignificant increase of CRT compared with thickness observed in second month. Two months after the treatment, we found an increase in intraocular pressure in 36% of cases and a further decrease during the final visit 6 months after the treatment. During the treatment, there were no significant differences in endothelial cell density in branch retinal vein occlusion and central retinal vein occlusion. We found the intravitreal dexamethasone implant to be safe, well tolerated, and likely to lead to fast morphological and functional improvement of the macula and visual rehabilitation in patients with ME due to retinal vein occlusion. PMID

  2. Evaluation of the effectiveness and safety of glucocorticoids intravitreal implant therapy in macular edema due to retinal vein occlusion

    PubMed Central

    Michalska-Małecka, Katarzyna; Gaborek, Aneta; Nowak, Mariusz; Halat, Tomasz; Pawłowska, Mariola; Śpiewak, Dorota

    2016-01-01

    The purpose of this study was to evaluate the impact of intravitreal dexamethasone implant (Ozurdex) on macular morphology and functions in eyes with macular edema (ME) secondary to retinal vein occlusion. Efficacy outcomes of the treatment were best-corrected visual acuity (BCVA) and central retinal thickness (CRT). Safety outcomes were intraocular pressure and cornea endothelial cell density. The study was conducted by the prospective analysis on 36 patients (17 women and 19 men) aged 28–77 years (the average age was 58±15 years) treated with the injection of dexamethasone implant because of the persistent ME at the Department of Ophthalmology and Ophthalmology Outpatient Clinic of the University Centre of Ophthalmology and Oncology in Katowice. The studied group included 16 patients with central retinal vein occlusion (16 eyes), and 20 patients with branch retinal vein occlusion (20 eyes). We found a significant increase of BCVA after first, second, and third month of treatment. Six months after the treatment, BCVA decreased, although not significantly compared with the value obtained in the third month. Two months after the intravitreal implantation of dexamethasone delivery system, CRT was 338±163 μm and was significantly lower compared with pretreatment value. Between third and sixth month after the treatment, we found insignificant increase of CRT compared with thickness observed in second month. Two months after the treatment, we found an increase in intraocular pressure in 36% of cases and a further decrease during the final visit 6 months after the treatment. During the treatment, there were no significant differences in endothelial cell density in branch retinal vein occlusion and central retinal vein occlusion. We found the intravitreal dexamethasone implant to be safe, well tolerated, and likely to lead to fast morphological and functional improvement of the macula and visual rehabilitation in patients with ME due to retinal vein occlusion. PMID

  3. Spatial and temporal vision of macaques after central retinal lesions

    SciTech Connect

    Merigan, W.H.; Pasternak, T.; Zehl, D.

    1981-07-01

    Spatial contrast and temporal modulation sensitivity of two macaque monkeys were measured at three luminance levels before and after binocular laser coagulation of the fovea. The radius of the lesions ranged from 1.6 to 2.2 degree from the center of the fovea. After placement of the lesions, the visibility of high spatial frequencies was greatly reduced, although sensitivity at middle and low spatial frequencies was unaffected. No loss of spatial resolution was found at the lowest luminance tested. When temporal modulation sensitivity was tested with 4 deg targets, foveal lesions had no effect at any temporal frequency or luminance. However, with a 0.57 degree target, sensitivity to lower temporal frequencies was impaired. Thus visual loss after destruction of the fovea is limited to high luminance, small targets, and the resolution of fine detail.

  4. Cystitis - acute

    MedlinePlus

    Uncomplicated urinary tract infection; UTI - acute; Acute bladder infection; Acute bacterial cystitis ... International clinical practice guidelines for the treatment of acute uncomplicated cystitis and pyelonephritis in women: A 2010 ...

  5. Gene therapy for retinal degeneration.

    PubMed

    Reichel, M B; Ali, R R; Hunt, D M; Bhattacharya, S S

    1997-01-01

    Inherited retinal degenerations are a group of diseases leading to blindness through progressive loss of vision in many patients. Although with the cloning of more and more disease genes the knowledge on the molecular genetics of these conditions and on the apoptotic pathway as the common disease mechanism is steadily increasing, there is still no cure for those affected. In recent years, new experimental treatments have evolved through the efforts of many investigators and have been explored in animal models. The rationale of the different strategies for developing a treatment based on gene replacement or rescue of the diseased neuronal tissue with growth factors will be outlined and discussed in this paper. PMID:9323717

  6. Integration of retinal image sequences

    NASA Astrophysics Data System (ADS)

    Ballerini, Lucia

    1998-10-01

    In this paper a method for noise reduction in ocular fundus image sequences is described. The eye is the only part of the human body where the capillary network can be observed along with the arterial and venous circulation using a non invasive technique. The study of the retinal vessels is very important both for the study of the local pathology (retinal disease) and for the large amount of information it offers on systematic haemodynamics, such as hypertension, arteriosclerosis, and diabetes. In this paper a method for image integration of ocular fundus image sequences is described. The procedure can be divided in two step: registration and fusion. First we describe an automatic alignment algorithm for registration of ocular fundus images. In order to enhance vessel structures, we used a spatially oriented bank of filters designed to match the properties of the objects of interest. To evaluate interframe misalignment we adopted a fast cross-correlation algorithm. The performances of the alignment method have been estimated by simulating shifts between image pairs and by using a cross-validation approach. Then we propose a temporal integration technique of image sequences so as to compute enhanced pictures of the overall capillary network. Image registration is combined with image enhancement by fusing subsequent frames of a same region. To evaluate the attainable results, the signal-to-noise ratio was estimated before and after integration. Experimental results on synthetic images of vessel-like structures with different kind of Gaussian additive noise as well as on real fundus images are reported.

  7. Lhx2 Is an Essential Factor for Retinal Gliogenesis and Notch Signaling

    PubMed Central

    de Melo, Jimmy; Zibetti, Cristina; Clark, Brian S.; Hwang, Woochang; Miranda-Angulo, Ana L.; Qian, Jiang

    2016-01-01

    during all stages of MG development. We also show that Lhx2 regulates directly the expression of components of the Notch signaling pathway, which promotes retinal Müller gliogenesis, as well as multiple gliogenic transcription factors. We further demonstrate that Lhx2 is required for Hes5-dependent gliogenesis. This study identifies Lhx2 as a central transcriptional regulator of both Notch-dependent and Notch-independent components of retinal gliogenesis. PMID:26911688

  8. Regulatory and Economic Considerations of Retinal Drugs.

    PubMed

    Shah, Ankoor R; Williams, George A

    2016-01-01

    The advent of anti-VEGF therapy for neovascular age-related macular degeneration and macular edema secondary to retinal vein occlusion and diabetes mellitus has prevented blindness in tens of thousands of people. However, the costs of these drugs are without precedent in ophthalmic drug therapeutics. An analysis of the financial implications of retinal drugs and the impact of the Food and Drug Administration on treatment of retinal disease must include not only an evaluation of the direct costs of the drugs and the costs associated with their administration, but also the cost savings which accrue from their clinical benefit. This chapter will discuss the financial and regulatory issues associated with retinal drugs.

  9. [Ocular hypertension after surgery for retinal detachment].

    PubMed

    Muşat, O; Cristescu, R; Coman, Corina; Asandi, R

    2012-01-01

    This papers presents a case of a patient with retinal detachement, 3 days ago operated (posterior vitrectomy internal tamponament with silicon oil 1000) who develop increased ocular pressure following silicon oil output in the anterior chamber.

  10. Imaging retinal mosaics in the living eye.

    PubMed

    Rossi, E A; Chung, M; Dubra, A; Hunter, J J; Merigan, W H; Williams, D R

    2011-03-01

    Adaptive optics imaging of cone photoreceptors has provided unique insight into the structure and function of the human visual system and has become an important tool for both basic scientists and clinicians. Recent advances in adaptive optics retinal imaging instrumentation and methodology have allowed us to expand beyond cone imaging. Multi-wavelength and fluorescence imaging methods with adaptive optics have allowed multiple retinal cell types to be imaged simultaneously. These new methods have recently revealed rod photoreceptors, retinal pigment epithelium (RPE) cells, and the smallest retinal blood vessels. Fluorescence imaging coupled with adaptive optics has been used to examine ganglion cells in living primates. Two-photon imaging combined with adaptive optics can evaluate photoreceptor function non-invasively in the living primate retina.

  11. Imaging retinal mosaics in the living eye

    PubMed Central

    Rossi, E A; Chung, M; Dubra, A; Hunter, J J; Merigan, W H; Williams, D R

    2011-01-01

    Adaptive optics imaging of cone photoreceptors has provided unique insight into the structure and function of the human visual system and has become an important tool for both basic scientists and clinicians. Recent advances in adaptive optics retinal imaging instrumentation and methodology have allowed us to expand beyond cone imaging. Multi-wavelength and fluorescence imaging methods with adaptive optics have allowed multiple retinal cell types to be imaged simultaneously. These new methods have recently revealed rod photoreceptors, retinal pigment epithelium (RPE) cells, and the smallest retinal blood vessels.