Microsurgical Resection of Lateral Tuberculum Sellae Meningioma: Operative Video.

PubMed

Cândido, Duarte N C; Nakashima, Paulo E H; de Oliveira, Jean Gonçalves; Borba, Luis A B

2018-02-01

Tuberculum Sellae Meningiomas (TSMs) are lesions dramatically related to the optic apparatus once the principal clinical complain remains on visual alterations. This is the main picture on decision making to evaluate the best time, risk-benefit, and surgical approaches to the patient treatment. In this video, we present a 65 years old female with 30 days complaint of unilateral (right) complete blindness and complete impaired right eye field test. On physical examination, there were normal pupillary function to light tests. The scans demonstrated the presence of a TSM mostly related to the right optic nerve and encasing it altogether with the right internal carotid artery. Promptly, surgery was addressed using a modified one piece cranio-orbital-zygomatic approach with extra-dural anterior clinoidectomy, as this is the procedure of choice of the senior author (LB), with easy access to decompression of the optic canal and nerve. As demonstrated on the video, the optic nerve was encased by the tumor and pushed upwards against the falciform ligament. Complete resection and decompression was established with step by step dissection, starting unroofing the optic canal, opening the ligament and finally with carefully tumor debulking. Pathology demonstrated a grade one meningioma. The patient improved remarkably her visual acuity and visual field tests on the postoperative period, emphasizing the importance of early treatment for nerve function outcome. The link to the video can be found at: https://youtu.be/pALZqDUkltQ .

Diagnostic value of neuro-ophthalmological signs in cases of Chiari I malformation.

PubMed

Bekerman, Inessa; Sigal, Tal; Kimiagar, Itzhak; Almer, Zina Evy; Vaiman, Michael

2016-12-01

Our purpose was to evaluate the diagnostic value of measuring diameters of optic nerve sheath (ONSD), presence/absence of papilledema, tortuosity of the optic nerve, flattening of the posterior sclera, and intraocular protrusion of the prelaminar optic nerve for intracranial pressure assessment in cases of Chiari I malformation. In a retrospective study, MRI data of 37 consecutive pediatric patients with Chiari malformation and data of 400 patients without intracranial pathology were compared and analyzed. ONSDs were measured at the point where the ophthalmic artery crosses the optic nerve (anatomical landmark). The correlation analysis was performed with clinical findings, gender, age, papilledema, and other neuro-ophthalmological findings. ONSD was enlarged in 38 % of cases of Chiari malformation. The enlargement was bilateral, no correlation with age or gender was found (p = 0.67 and p = 0.76, respectively). The presence of papilledema was detected in 19 % of cases presenting less valuable diagnostic sign if compared with ONSD. The tortuosity of the optic nerve was found in 22 % of cases, but in three patients, it was unilateral. All patients with enlarged ONSD and other neuro-ophthalmological signs present were treated surgically, while most of the patients without these signs (20/23) were treated conservatively. In majority of pediatric cases of Chiari malformation, the ONSD is not enlarged and other neuro-ophthalmological signs are not present. Detecting the enlarged ONSD and other neuro-ophthalmological signs in cases of Chiari malformation may indicate the elevated intracranial pressure and necessity for urgent surgical intervention.

Simultaneous central retinal artery occlusion and optic nerve vasculitis in Crohn disease.

PubMed

Coussa, Razek Georges; Ali-Ridha, Andre; Vila, Natalia; Alshareef, Rayan; Chen, John

2017-04-01

To describe a case of Crohn disease presenting as occlusive vasculitis resulting in a central retinal artery occlusion (CRAO) in one eye and transient ischemic optic neuropathy in the fellow eye. An 18-year-old patient recently diagnosed with biopsy-proven Crohn disease presented with CRAO OD after a previous episode of transient visual loss OS. Extensive workup was negative for other autoimmune or infectious etiologies. The patient was started on intravenous methylprednisolone for 72 h followed by maintenance dose of azathioprine and oral prednisone. Signs of inflammation resolved gradually with some improvement of visual acuity despite developing optic atrophy. To our knowledge, this is the first case of unilateral CRAO and bilateral optic nerve occlusive vasculitis in Crohn disease, which should be considered as an etiology of retinal vascular occlusive disorders especially in young patients. It is important for ophthalmologists to be aware of the ophthalmic risks associated with Crohn disease as aggressive treatment with systemic steroids and immunosuppressive agents is often needed.

[Atypical optic neuritis in systemic lupus erythematosus (SLE)].

PubMed

Eckstein, A; Kötter, I; Wilhelm, H

1995-11-01

A 67-year-old woman experienced acute unilateral visual loss accompanied by pain with eye movements. There was a marked relative afferent pupillary defect and a nerve fiber bundle defect in the upper half of the visual field. Optic discs were normal. After 4 days vision worsened to motion detection and only a temporal island was left in the visual field. The optic disc margin was blurred. Since thirty years she had been suffering from renal insufficiency. Immunoserologic examination revealed elevated ANA and DS-DNA antibody titers. An optic neuritis in systemic lupus erythematosus was diagnosed, which is called atopic, because of its association to a systemic disease and the old age of the patient. The patient was treated with 100 mg prednisolone/day, slowly tapered. Within 6 weeks visual acuity improved to 0.6 and visual field normalized except for a small nerve fiber bundle defect. Autoimmune optic neuritis often responds to treatment with corticosteroids. Early onset of treatment is important. Immunopathologic examinations are an important diagnostic tool in atopic optic neuritis. Their results may even have consequences for the treatment of the underlying disease.

Generalized mechanical pain sensitivity over nerve tissues in patients with strictly unilateral migraine.

PubMed

Fernández-de-las-Peñas, César; Arendt-Nielsen, Lars; Cuadrado, María Luz; Pareja, Juan A

2009-06-01

No study has previously analyzed pressure pain sensitivity of nerve trunks in migraine. This study aimed to examine the differences in mechanical pain sensitivity over specific nerves between patients with unilateral migraine and healthy controls. Blinded investigators assessed pressure pain thresholds (PPT) over the supra-orbital nerves (V1) and peripheral nerve trunks of both upper extremities (median, radial, and ulnar nerves) in 20 patients with strictly unilateral migraine and 20 healthy matched controls. Pain intensity after palpation over both supra-orbital nerves was also assessed. A pressure algometer was used to quantify PPT, whereas a 10-point numerical pain rate scale was used to evaluate pain to palpation over the supra-orbital nerve. The analysis of covariance revealed that pain to palpation over the supra-orbital nerve was significantly higher (P<0.001) on the symptomatic side (mean: 3.4, SD: 1.5) as compared with the nonsymptomatic side (mean: 0.5, SD: 1.2) in patients with migraine and both the dominant (mean: 0.2, SD: 0.4) and nondominant (mean: 0.3, SD: 0.5) sides in healthy controls. PPT assessed over the supra-orbital nerve on the symptomatic side (mean: 1.05, SD: 0.2 kg/cm) was significantly lower (P<0.05) than PPT measurements on the nonsymptomatic side (mean: 1.35, SD: 0.3 kg/cm) and either the dominant (mean: 1.9, SD: 0.2 kg/cm) or nondominant (mean: 1.9, SD: 0.3 kg/cm) sides in controls (P<0.001). Finally, PPT assessed over the median, ulnar, and radial nerves were significantly lower in patients with migraine as compared with controls (P<0.001), without side-to-side differences (P>0.6). In patients with unilateral migraine, we found increased mechano-sensitivity of the supra-orbital nerve on the symptomatic side of the head. Outside the head, the same patients showed increased mechano-sensitivity of the main peripheral nerves of both upper limbs, without asymmetries. Such diffuse hypersensitivity of the peripheral nerves lends further evidence to the presence of a state of hyperexcitability of the central nervous system in patients with unilateral migraine.

Unilateral optic nerve transection alters light response of suprachiasmatic nucleus and intergeniculate leaflet

NASA Technical Reports Server (NTRS)

Tang, I-Hsiung; Murakami, Dean M.; Fuller, Charles A.

2002-01-01

The suprachiasmatic nucleus (SCN), the circadian pacemaker, receives photic input directly from the retina to synchronize the pacemaker to the environment. Additionally, the intergeniculate leaflet (IGL), which innervates the SCN, is known to modulate the retinal photic input to the SCN. To further understand the role of the IGL in mediating the photic input to the SCN, this study examined the effects of unilateral optic nerve transection (UONx) on the photic response of the SCN and IGL in adult and neonatal hamsters. UONx led to an overall reduction in light-induced c-Fos expression in the SCN and IGL. The c-Fos expression was greater in the SCN ipsilateral to the remaining eye, despite a symmetrically bilateral retinohypothalamic tract projection as revealed by intraocular injection of horseradish peroxidase. In contrast, UONx led to a greater c-Fos expression in the contralateral IGL. The contralateral IGL of UONx animals also revealed more neuropeptide Y-immunoreactive neurons, while the ipsilateral SCN of these animals exhibited a denser neuropeptide Y terminal field. The neonates with UONx showed a similar pattern with a slight compensation of the photic-induced c-Fos in the SCN. This study suggests that the IGL may have an ipsilateral inhibitory effect in mediating retinal photic input to the SCN.

Retinal glutamate transporter changes in experimental glaucoma and after optic nerve transection in the rat.

PubMed

Martin, Keith R G; Levkovitch-Verbin, Hana; Valenta, Danielle; Baumrind, Lisa; Pease, Mary Ellen; Quigley, Harry A

2002-07-01

High levels of glutamate can be toxic to retinal ganglion cells. Effective buffering of extracellular glutamate by retinal glutamate transporters is therefore important. This study was conducted to investigate whether glutamate transporter changes occur with two models of optic nerve injury in the rat. Glaucoma was induced in one eye of 35 adult Wistar rats by translimbal diode laser treatment to the trabecular meshwork. Twenty-five more rats underwent unilateral optic nerve transection. Two glutamate transporters, GLAST (EAAT-1) and GLT-1 (EAAT-2), were studied by immunohistochemistry and quantitative Western blot analysis. Treated and control eyes were compared 3 days and 1, 4, and 6 weeks after injury. Optic nerve damage was assessed semiquantitatively in epoxy-embedded optic nerve cross sections. Trabecular laser treatment resulted in moderate intraocular pressure (IOP) elevation in all animals. After 1 to 6 weeks of experimental glaucoma, all treated eyes had significant optic nerve damage. Glutamate transporter changes were not detected by immunohistochemistry. Western blot analysis demonstrated significantly reduced GLT-1 in glaucomatous eyes compared with control eyes at 3 days (29.3% +/- 6.7%, P = 0.01), 1 week (55.5% +/- 13.6%, P = 0.02), 4 weeks (27.2% +/- 10.1%, P = 0.05), and 6 weeks (38.1% +/- 7.9%, P = 0.01; mean reduction +/- SEM, paired t-tests, n = 5 animals per group, four duplicate Western blot analyses per eye). The magnitude of the reduction in GLT-1 correlated significantly with mean IOP in the glaucomatous eye (r(2) = 0.31, P = 0.01, linear regression). GLAST was significantly reduced (33.8% +/- 8.1%, mean +/- SEM) after 4 weeks of elevated IOP (P = 0.01, paired t-test, n = 5 animals per group). In contrast to glaucoma, optic nerve transection resulted in an increase in GLT-1 compared with the control eye (P = 0.01, paired t-test, n = 15 animals). There was no significant change in GLAST after transection. GLT-1 and GLAST were significantly reduced in an experimental rat glaucoma model, a response that was not found after optic nerve transection. Reductions in GLT-1 and GLAST may increase the potential for glutamate-induced injury to RGC in glaucoma.

Evidence for a systemic regulation of neurotrophin synthesis in response to peripheral nerve injury.

PubMed

Shakhbazau, Antos; Martinez, Jose A; Xu, Qing-Gui; Kawasoe, Jean; van Minnen, Jan; Midha, Rajiv

2012-08-01

Up-regulation of neurotrophin synthesis is an important mechanism of peripheral nerve regeneration after injury. Neurotrophin expression is regulated by a complex series of events including cell interactions and multiple molecular stimuli. We have studied neurotrophin synthesis at 2 weeks time-point in a transvertebral model of unilateral or bilateral transection of sciatic nerve in rats. We have found that unilateral sciatic nerve transection results in the elevation of nerve growth factor (NGF) and NT-3, but not glial cell-line derived neurotrophic factor or brain-derived neural factor, in the uninjured nerve on the contralateral side, commonly considered as a control. Bilateral transection further increased NGF but not other neurotrophins in the nerve segment distal to the transection site, as compared to the unilateral injury. To further investigate the distinct role of NGF in regeneration and its potential for peripheral nerve repair, we transduced isogeneic Schwann cells with NGF-encoding lentivirus and transplanted the over-expressing cells into the distal segment of a transected nerve. Axonal regeneration was studied at 2 weeks time-point using pan-neuronal marker NF-200 and found to directly correlate with NGF levels in the regenerating nerve. © 2012 The Authors. Journal of Neurochemistry © 2012 International Society for Neurochemistry.

Glaucoma drops control intraocular pressure and protect optic nerves in a rat model of glaucoma.

PubMed

Morrison, J C; Nylander, K B; Lauer, A K; Cepurna, W O; Johnson, E

1998-03-01

To determine whether chronic topical glaucoma therapy can control intraocular pressure (IOP) and protect nerve fibers in a rat model of pressure-induced optic nerve damage. Sixteen adult Brown Norway rats were-administered unilateral episcleral vein injections of hypertonic saline to produce scarring of the aqueous humor outflow pathways. Twice daily applications of either artificial tears (n = 6), 0.5% betaxolol (n = 5), or 0.5% apraclonidine (n = 5) were delivered to both eyes, and awake pressures were monitored with a TonoPen XL tonometer for 17 days before the rats were killed. For animals administered artificial tears, the mean IOP of the experimental eyes was 39 +/- 2 mm Hg compared with 29 +/- 1 mm Hg for the control eyes. This difference was statistically significant (P < 0.001). Mean IOPs in the experimental eyes of animals administered betaxolol and apraclonidine were 29 +/- 7 and 29 +/- 4 mm Hg, respectively, whereas the mean IOP in the control eyes was 28 +/- 1 mm Hg for both groups. There was no statistically significant difference among these values. The mean IOP for the experimental eyes in the betaxolol and apraclonidine groups was lower than that in animals administered artificial tears (P = 0.003). Quantitative histologic analysis of optic nerve damage in experimental eyes showed that four of the six animals administered artificial tears had damage involving 100% of the neural area. This degree of damage appeared in only 3 of 10 animals administered glaucoma therapy. Optic nerve protection was closely correlated with IOP history because damage was limited to less than 10% of the cross-sectional area in all animals in which the maximal IOP was less than or equal to 39 mm Hg, more than 2 SD below the mean value for eyes administered artificial tears. Topical glaucoma therapy in this model can prevent IOP elevation and protect optic nerve fibers.

Unilateral abducens and bilateral facial nerve palsies associated with posterior fossa exploration surgery

PubMed Central

Khalil, Ayman; Clerkin, James; Mandiwanza, Tafadzwa; Green, Sandra; Javadpour, Mohsen

2016-01-01

Multiple cranial nerves palsies following a posterior fossa exploration confined to an extradural compartment is a rare clinical presentation. This case report describes a young man who developed a unilateral abducens and bilateral facial nerve palsies following a posterior fossa exploration confined to an extradural compartment. There are different theories to explain this presentation, but the exact mechanism remains unclear. We propose that this patient cranial nerve palsies developed following cerebrospinal fluid (CSF) leak, potentially as a consequence of rapid change in CSF dynamics. PMID:26951144

Post-traumatic Unilateral Avulsion of the Abducens Nerve with Damage to Cranial Nerves VII and VIII: Case Report.

PubMed

Yamasaki, Fumiyuki; Akiyama, Yuji; Tsumura, Ryu; Kolakshyapati, Manish; Adhikari, Rupendra Bahadur; Takayasu, Takeshi; Nosaka, Ryo; Kurisu, Kaoru

2016-07-01

Traumatic injuries of the abducens nerve as a consequence of facial and/or head trauma occur with or without associated cervical or skull base fracture. This is the first report on unilateral avulsion of the abducens nerve in a 29-year-old man with severe right facial trauma. In addition, he exhibited mild left facial palsy, and moderate left hearing disturbance. Magnetic resonance imaging (MRI) using fast imaging employing steady-state acquisition (FIESTA) revealed avulsion of left sixth cranial nerve. We recommend thin-slice MR examination in patients with abducens palsy after severe facial and/or head trauma.

Cupping in the Monkey Optic Nerve Transection Model Consists of Prelaminar Tissue Thinning in the Absence of Posterior Laminar Deformation

PubMed Central

Ing, Eliesa; Ivers, Kevin M.; Yang, Hongli; Gardiner, Stuart K.; Reynaud, Juan; Cull, Grant; Wang, Lin; Burgoyne, Claude F.

2016-01-01

Purpose To use optical coherence tomography (OCT) to test the hypothesis that optic nerve head (ONH) “cupping” in the monkey optic nerve transection (ONT) model does not include posterior laminar deformation. Methods Five monkeys (aged 5.5–7.8 years) underwent ONH and retinal nerve fiber layer (RNFL) OCT imaging five times at baseline and biweekly following unilateral ONT until euthanization at ∼40% RNFL loss. Retinal nerve fiber layer thickness (RNFLT) and minimum rim width (MRW) were calculated from each pre- and post-ONT imaging session. The anterior lamina cribrosa surface (ALCS) was delineated within baseline and pre-euthanasia data sets. Significant ONT versus control eye pre-euthanasia change in prelaminar tissue thickness (PLTT), MRW, RNFLT, and ALCS depth (ALCSD) was determined using a linear mixed-effects model. Eye-specific change in each parameter exceeded the 95% confidence interval constructed from baseline measurements. Results Animals were euthanized 49 to 51 days post ONT. Overall ONT eye change from baseline was significant for MRW (−26.2%, P = 0.0011), RNFLT (−43.8%, P < 0.0001), PLTT (−23.8%, P = 0.0013), and ALCSD (−20.8%, P = 0.033). All five ONT eyes demonstrated significant eye-specific decreases in MRW (−23.7% to −31.8%) and RNFLT (−39.6% to −49.7%). Four ONT eyes showed significant PLTT thinning (−23.0% to −28.2%). The ALCS was anteriorly displaced in three of the ONT eyes (−25.7% to −39.2%). No ONT eye demonstrated posterior laminar displacement. Conclusions Seven weeks following surgical ONT in the monkey eye, ONH cupping involves prelaminar and rim tissue thinning without posterior deformation of the lamina cribrosa. PMID:27168368

A review of orbital and intracranial magnetic resonance imaging in 79 canine and 13 feline patients (2004-2010).

PubMed

Armour, Micki D; Broome, Michael; Dell'Anna, Giuseppe; Blades, Natalie J; Esson, Douglas W

2011-07-01

To review the distribution of orbital and intracranial disease in canine and feline patients undergoing magnetic resonance imaging (MRI) following referral to a veterinary ophthalmologist and to correlate results of MRI with pathologic conditions including neoplasia, suspected optic neuritis (ON) and orbital cellulitis. Recognized and emerging imaging techniques are reviewed. Medical records of 79 canine and 13 feline patients were reviewed. Neoplasia was diagnosed in 53/92 (57.6%) of patients. The most prevalent types of neoplasia were carcinoma (16/53, 30.1%), sarcoma (11/53, 20.8%), lymphoma (8/53, 15.1%) and presumptive meningioma (9/53, 17.0%). Carcinomas and sarcomas were characterized by bony lysis and intracranial/sinonasal extension. Lymphoma was generally unilateral, less invasive and originated from the ventromedial orbit. Intracranial masses representing presumptive meningiomas frequently exhibited a 'dural tail' sign. Diagnosis of suspected ON was made in 13 of 92 (14.1%) patients. Results of MRI in patients with suspected ON included unilateral optic nerve hyperintensity (3/13, 23.0%), bilateral optic nerve hyperintensity (1/13, 7.7%) and optic chiasmal hyperintensity (3/13, 23.0%). Seven suspected ON patients demonstrated intracranial multifocal patchy contrast enhancement (7/13, 53.8%). Diagnosis of orbital cellulitis was made in 12/92 (13.0%) patients. Orbital neoplasia was the most common pathologic condition detected. Essential Roentgen characteristics are helpful when diagnosing pathologic processes and providing prognoses in cases of orbital or intracranial disease. Magnetic resonance imaging comprises an important diagnostic component in cases of suspected ON. Emerging contrast and functional MRI techniques as well as SI data may increase our ability to characterize disease processes. © 2011 American College of Veterinary Ophthalmologists.

[Multiple ocular coloboma (MOC) with persistent pupillary membrane in the snow leopard (Panthera uncia)].

PubMed

Schäffer, E; Wiesner, H; von Hegel, G

1988-01-01

In a litter of three snow leopards, bilateral colobomata of the upper temporal eyelids, bilateral persistent pupillary membranes and a unilateral coloboma of the optic nerve entrance are described as "Multiple Ocular Colobomata" (MOC). The causal pathogenesis of each of the colobomata is discussed comparatively. The colobomata of the eyelids, essential feature of the MOC syndrome in snow leopards, are most probably not of hereditary, but rather of intrauterine infectious viral origin.

Shrinkage of ipsilateral taste buds and hyperplasia of contralateral taste buds following chorda tympani nerve transection.

PubMed

Li, Yi-Ke; Yang, Juan-Mei; Huang, Yi-Bo; Ren, Dong-Dong; Chi, Fang-Lu

2015-06-01

The morphological changes that occur in the taste buds after denervation are not well understood in rats, especially in the contralateral tongue epithelium. In this study, we investigated the time course of morphological changes in the taste buds following unilateral nerve transection. The role of the trigeminal component of the lingual nerve in maintaining the structural integrity of the taste buds was also examined. Twenty-four Sprague-Dawley rats were randomly divided into three groups: control, unilateral chorda tympani nerve transection and unilateral chorda tympani nerve transection + lingual nerve transection. Rats were allowed up to 42 days of recovery before being euthanized. The taste buds were visualized using a cytokeratin 8 antibody. Taste bud counts, volumes and taste receptor cell numbers were quantified and compared among groups. No significant difference was detected between the chorda tympani nerve transection and chorda tympani nerve transection + lingual nerve transection groups. Taste bud counts, volumes and taste receptor cell numbers on the ipsilateral side all decreased significantly compared with control. On the contralateral side, the number of taste buds remained unchanged over time, but they were larger, and taste receptor cells were more numerous postoperatively. There was no evidence for a role of the trigeminal branch of the lingual nerve in maintaining the structural integrity of the anterior taste buds.

Sonographic evaluation of the greater occipital nerve in unilateral occipital neuralgia.

PubMed

Cho, John Chin-Suk; Haun, Daniel W; Kettner, Norman W

2012-01-01

Occipital neuralgia is a headache that may result from greater occipital nerve entrapment. Entrapped peripheral nerves typically have an increase in cross-sectional area. The purpose of this study was to measure the cross-sectional area and circumference of symptomatic and asymptomatic greater occipital nerves in patients with unilateral occipital neuralgia and to correlate the greater occipital nerve cross-sectional area with headache severity, sex, and body mass index. Both symptomatic and contralateral asymptomatic greater occipital nerve cross-sectional areas and circumferences were measured by a single examiner using sonography in 17 patients. The Wilcoxon signed rank test and Spearman rank order correlation coefficient were used to analyze the data. Significant differences between the cross-sectional areas and circumferences of the symptomatic and asymptomatic greater occipital nerves were noted (P < .001). No difference existed in cross-sectional area (P = .40) or circumference (P = .10) measurements of the nerves between male and female patients. A significant correlation existed between the body mass index and symptomatic (r = 0.424; P = .045) and asymptomatic (r = 0.443; P = .037) cross-sectional areas. There was no correlation shown between the cross-sectional area of the symptomatic nerve and the severity of Headache Impact Test 6 scores (r = -0.342; P = .179). We report sonographic evidence showing an increased cross-sectional area and circumference of the symptomatic greater occipital nerve in patients with unilateral occipital neuralgia.

Unilateral abducens and bilateral facial nerve palsies associated with posterior fossa exploration surgery.

PubMed

Khalil, Ayman; Clerkin, James; Mandiwanza, Tafadzwa; Green, Sandra; Javadpour, Mohsen

2016-03-06

Multiple cranial nerves palsies following a posterior fossa exploration confined to an extradural compartment is a rare clinical presentation. This case report describes a young man who developed a unilateral abducens and bilateral facial nerve palsies following a posterior fossa exploration confined to an extradural compartment. There are different theories to explain this presentation, but the exact mechanism remains unclear. We propose that this patient cranial nerve palsies developed following cerebrospinal fluid (CSF) leak, potentially as a consequence of rapid change in CSF dynamics. Published by Oxford University Press and JSCR Publishing Ltd. All rights reserved. © The Author 2016.

Effect of optic neuritis on progressive axonal damage in multiple sclerosis patients.

PubMed

Garcia-Martin, E; Pueyo, V; Ara, J R; Almarcegui, C; Martin, J; Pablo, L; Dolz, I; Sancho, E; Fernandez, F J

2011-07-01

The objective of this research was to study the effect of optic neuritis (ON) on axonal damage in multiple sclerosis (MS) patients. Specifically, we compared changes over 2 years in the retinal nerve fibre layer (RNFL) between affected and contralateral eyes in MS patients with a prior history of ON. Thirty-four patients with one unilateral definitive episode of ON were included and underwent a complete ophthalmic examination, optical coherence tomography (OCT), scanning laser polarimetry, visual evoked potentials (VEP) and pattern electroretinogram (pERG). All patients were re-evaluated at 12 and 24 months. Parameters were compared between ON-affected and contralateral eyes in an initial exploration and over the course of the follow-up. Correlations between parameter changes were analysed. RNFL thickness and functional parameters showed more affection in ON eyes (p ≤ 0.05), but changes in measurements during the study were similar between both groups of eyes. Progressive axonal loss can be detected in the optic nerve, but ON is not a risk factor for increased chronic damage in MS patients without ophthalmic relapses. Loss of the RNFL is caused by progressive degeneration associated with the disease.

Unilateral Opening of Rat Blood-Brain Barrier Assisted by Diagnostic Ultrasound Targeted Microbubbles Destruction.

PubMed

Xu, Yali; Cui, Hai; Zhu, Qiong; Hua, Xing; Xia, Hongmei; Tan, Kaibin; Gao, Yunhua; Zhao, Jing; Liu, Zheng

2016-01-01

Objective. Blood-brain barrier (BBB) is a key obstacle that prevents the medication from blood to the brain. Microbubble-enhanced cavitation by focused ultrasound can open the BBB and proves to be valuable in the brain drug delivery. The study aimed to explore the feasibility, efficacy, and safety of unilateral opening of BBB using diagnostic ultrasound targeted microbubbles destruction in rats. Methods. A transtemporal bone irradiation of diagnostic ultrasound and intravenous injection of lipid-coated microbubbles were performed at unilateral hemisphere. Pathological changes were monitored. Evans Blue extravasation grades, extraction from brain tissue, and fluorescence optical density were quantified. Lanthanum nitrate was traced by transmission electron microscopy. Results. After diagnostic ultrasound mediated microbubbles destruction, Evans Blue extravasation and fluorescence integrated optical density were significantly higher in the irradiated hemisphere than the contralateral side (all p < 0.01). Erythrocytes extravasations were demonstrated in the ultrasound-exposed hemisphere (4 ± 1, grade 2) while being invisible in the control side. Lanthanum nitrate tracers leaked through interendothelial cleft and spread to the nerve fiber existed in the irradiation side. Conclusions. Transtemporal bone irradiation under DUS mediated microbubble destruction provides us with a more accessible, safer, and higher selective BBB opening approach in rats, which is advantageous in brain targeted drugs delivery.

Unilateral phrenic nerve lesion in Lyme neuroborreliosis

PubMed Central

2013-01-01

Background Among a variety of more common differential diagnoses, the aetiology of acute respiratory failure includes Lyme neuroborreliosis. Case presentation We report an 87-years old huntsman with unilateral phrenic nerve palsy as a consequence of Lyme neuroborreliosis. Conclusion Although Lyme neuroborreliosis is a rare cause of diaphragmatic weakness, it should be considered in the differential workup because of its potentially treatable nature. PMID:23327473

Syringomyelia presenting with unilateral optic neuropathy: a case report.

PubMed

Ngoo, Qi Zhe; Tai, Evelyn Li Min; Wan Hitam, Wan Hazabbah

2017-01-01

In this case report, we present two cases of syringomyelia with optic neuropathy. In Case 1, a 36-year-old Malay lady presented to our clinic with acute onset of blurring of vision in her left eye that she experienced since past 1 month. She was diagnosed with syringomyelia 12 years ago and was on conservative management. Her visual acuity was 6/6 in the right eye and counting fingers at 1 m in the left. There was a positive relative afferent pupillary defect in her left eye. Optic nerve functions of her left eye were reduced. Visual field showed a left inferior field defect. Her extraocular muscle movements were full. Magnetic resonance imaging of the brain and spine showed syringomyelia at the level of C2-C6 and T2-T9. Both of her optic nerves were normal. Her condition improved with intravenous and oral corticosteroids. In Case 2, a 44-year-old Malay lady presented to our clinic with a progressive central scotoma in her right eye that she experienced since past 1 month. She had previous history of recurrent episodes of weakness in both of her lower limbs from past 8 months. Visual acuity in her right and left eye was 6/9 and 6/6, respectively. The relative afferent pupillary defect in her right eye was positive. Optic nerve functions of her right eye were affected. Visual field showed a central scotoma in her right eye. Her extraocular muscle movements were full. Fundoscopy of her right eye showed a pale optic disc. Her left eye fundus was normal. Magnetic resonance imaging of the brain and spine showed syringomyelia at T3-T6. Both of her optic nerves were normal. A diagnosis of syringomyelia with right optic atrophy was performed. Her condition improved with intravenous and oral corticosteroids. Optic neuropathy is a rare neuro-ophthalmic manifestation in patients with syringomyelia. Prompt diagnosis and timely management are essential to avoid a poor visual outcome. Intravenous corticosteroids are beneficial in the treatment of early optic neuropathy in syringomyelia.

Rare encounter of unilateral facial nerve palsy in an adolescent with Guillain-Barré syndrome

PubMed Central

Iqbal, Mehtab; Sharma, Parnika; Charadva, Creana; Prasad, Manish

2016-01-01

Unilateral facial nerve palsy is rarely encountered in Guillain-Barré syndrome (GBS). We report a case of an adolescent girl who presented with peripheral ascending weakness, preceded by Campylobacter jejuni infection. After treatment with intravenous immunoglobulin, the peripheral weakness improved. Electro-diagnostic testing confirmed axonal dysfunction and the patient was positive for antiganglioside antibodies. However, the patient developed unilateral left-sided facial weakness. She was managed with further intravenous immunoglobulin and intensive physiotherapy. The outcome for facial palsy was very good, with almost complete resolution after 2 weeks. PMID:26823357

Toxocara optic neuropathy: clinical features and ocular findings.

PubMed

Choi, Kwang-Dong; Choi, Jae-Hwan; Choi, Seo-Young; Jung, Jae Ho

2018-01-01

We evaluated thirteen eyes of twelve patients diagnosed clinically and serologically with Toxocara optic neuropathy. Eleven patients had unilateral involvement and one patient had bilateral optic neuropathy. Eight patients (66.7%) had a possible infection source to Toxocara. Six patients (50%) had painless acute optic neuropathy. Ten eyes had asymmetric, sectorial optic disc edema with peripapillary infiltration and three eyes had diffuse optic disc edema. Eosinophilia was noted in five patients (41.7%) and optic nerve enhancement was observed in eight of eleven eyes (72.7%) with available orbit magnetic resonance imaging (MRI). Mean visual acuity significantly improved following treatment [mean logarithmic of the minimum angle of resolution (logMAR) 0.94±0.56 at baseline and 0.47±0.59 at the final ( P =0.02)]. Asymmetric optic disc edema with a peripapillary lesion and a history of raw meat ingestion were important clues for diagnosing Toxocara optic neuropathy. Additionally, Toxocara IgG enzyme-linked immunosorbent assay (ELISA) test and evaluating eosinophil may be helpful for diagnosis.

Toxocara optic neuropathy: clinical features and ocular findings

PubMed Central

Choi, Kwang-Dong; Choi, Jae-Hwan; Choi, Seo-Young; Jung, Jae Ho

2018-01-01

We evaluated thirteen eyes of twelve patients diagnosed clinically and serologically with Toxocara optic neuropathy. Eleven patients had unilateral involvement and one patient had bilateral optic neuropathy. Eight patients (66.7%) had a possible infection source to Toxocara. Six patients (50%) had painless acute optic neuropathy. Ten eyes had asymmetric, sectorial optic disc edema with peripapillary infiltration and three eyes had diffuse optic disc edema. Eosinophilia was noted in five patients (41.7%) and optic nerve enhancement was observed in eight of eleven eyes (72.7%) with available orbit magnetic resonance imaging (MRI). Mean visual acuity significantly improved following treatment [mean logarithmic of the minimum angle of resolution (logMAR) 0.94±0.56 at baseline and 0.47±0.59 at the final (P=0.02)]. Asymmetric optic disc edema with a peripapillary lesion and a history of raw meat ingestion were important clues for diagnosing Toxocara optic neuropathy. Additionally, Toxocara IgG enzyme-linked immunosorbent assay (ELISA) test and evaluating eosinophil may be helpful for diagnosis. PMID:29600190

Unilateral or bilateral vagotomy induces ovulation in both ovaries of rats with polycystic ovarian syndrome.

PubMed

Linares, Rosa; Hernández, Denisse; Morán, Carolina; Chavira, Roberto; Cárdenas, Mario; Domínguez, Roberto; Morales-Ledesma, Leticia

2013-07-17

Injecting estradiol valerate (EV) to pre-pubertal or adult female rat results in effects similar to those observed in women with polycystic ovarian syndrome (PCOS). One of the mechanisms involved in PCOS development is the hyperactivity of the sympathetic nervous system. In EV-induced PCOS rats, the unilateral sectioning of the superior ovarian nerve (SON) restores ovulation of the innervated ovary. This suggests that, in addition to the sympathetic innervation, other neural mechanisms are involved in the development/maintenance of PCOS. The aims of present study were analyze if the vagus nerve is one of the neural pathways participating in PCOS development. Ten-day old rats were injected with EV dissolved in corn oil. At 24-days of age sham-surgery, unilateral, or bilateral sectioning of the vagus nerve (vagotomy) was performed on these rats. The animals were sacrificed at 90-92 days of age, when they presented vaginal estrous preceded by a pro-estrus smear. In EV-induced PCOS rats, unilateral or bilateral vagotomy restored ovulation in both ovaries. Follicle-stimulating hormone (FSH) levels in PCOS rats with unilateral or bilateral vagotomy were lower than in control rats. This result suggests that in EV-induced PCOS rats the vagus nerve is a neural pathway participating in maintaining PCOS. The vagus nerve innervates the ovaries directly and indirectly through its synapsis in the celiac-superior-mesenteric ganglion, where the somas of neurons originating in the SON are located. Then, it is possible that vagotomy effects in EV-induced PCOS rats may be explained as a lack of communication between the central nervous system and the ovaries.

Sural nerve grafting in robotic laparoscopic radical prostatectomy: interim report.

PubMed

Mikhail, Albert A; Song, David H; Zorn, Kevin C; Orvieto, Marcelo A; Taxy, Jerome B; Lin, Shang P; Mendiola, Frederick P; Shalhav, Arieh L; Zagaja, Gregory P

2007-12-01

Sural nerve grafting for patients undergoing prostatectomy has been previously reported using open and minimally invasive methods. We report our experience with sural nerve grafting during robot-assisted laparoscopic radical prostatectomy (RLRP). Patients with preoperative potency and a minimum of 6 months follow-up were included in this prospective review. A total of 333 patients were identified between February 2003 and January 2006 who met these criteria including 22 of the 25 patients who underwent sural nerve grafting. Patients were divided into 5 groups to compare unilateral and bilateral sural nerve cohorts with non-nerve-sparing and unilateral and bilateral nerve-sparing groups. Patients were followed prospectively using health-related quality-of-life questionnaires. Twenty-two patients underwent sural nerve grafting that included three bilateral grafts. Mean follow-up was 14 months. There was no statistical difference in patients' ages, body mass index, preoperative prostate-specific antigen level, blood loss, complications, and positive margin rate. Operative time was statistically longer for both sural graft cohorts when compared with unilateral (without graft) and bilateral nerve sparing cohorts. No significant differences in subjective or objective sexual function, sexual bother, or urinary function were seen with 6 and 12 months follow-up, possibly related to smaller sural cohorts. Graft-related complications include leg pain in one patient. Sural nerve grafting during RLRP is technically feasible and safe and offers improved dexterity and visualization deep within the pelvis. However, a larger randomized cohort of patients will be required to validate any improved benefits afforded by the robot system.

Restoring tactile and erogenous penile sensation in low-spinal-lesion patients: procedural and technical aspects following 43 TOMAX nerve transfer procedures.

PubMed

Overgoor, Max L E; de Jong, Tom P V M; Kon, Moshe

2014-08-01

The "TOMAX" (TO MAX-imize sensation, sexuality, and quality of life) procedure restores genital sensation in men with low spinal lesions, improving sexual health, as shown previously. It connects the dorsal nerve of the penis to the intact ipsilateral ilioinguinal nerve, unilaterally or bilaterally. This study reports on the technical aspects based on 43 TOMAX nerve transfers. In 40 patients with no penile but intact groin sensation, 43 nerve transfers were performed. Data on patient selection, surgical history, anatomy of the ilioinguinal nerve and dorsal nerve of the penis, unilateral or bilateral surgery, surgical technique, complications, and patient information were collected prospectively. Regardless of origin, all patients with no penile but good groin sensation are eligible for the procedure, provided the ilioinguinal nerve is not damaged because of former inguinal surgery or absent because of anatomical variations. Selection of a unilateral or bilateral procedure depends on the presence or absence of reflex erections and bulbocavernosus reflex. Preliminary experience with the first three bilateral cases shows that it is technically feasible, with encouraging results. The surgical technique has evolved (described in detail, including video) to enhance outcome and reduce complications. Patients are better informed, resulting in realistic expectations. This article synthesizes the procedural and technical experience of 43 TOMAX nerve transfers. Anyone skilled in peripheral nerve surgery and microsurgery can adopt this concept and further develop it. The TOMAX procedure can then be used to restore erogenous penile sensation and improve the quality of sexual health in patients with absent penile but good groin sensation.

Surgical treatment of bronchial asthma by resection of the laryngeal nerve.

PubMed

Kurbon, Ubaidullo; Dodariyon, Hamza; Davlatov, Abdumalik; Janobilova, Sitora; Therwath, Amu; Mirshahi, Massoud

2015-10-08

Management of asthma in chronically affected patients is a serious health problem. Our aim was to show that surgical treatment of chronic bronchial asthma by unilateral resection of the internal branch of the superior laryngeal nerve (ib-SLN) is an adequateand lasting remedial response. In a retrospective study, 41 (26 male and 15 female) patients with bronchial chronic asthma were treated surgically during the period between 2005 and 2013. It consisted of a unilateral resection of the ib-SLN under optical zoom, on patients placed in supinator position. 35 patients (24 male and 11 female) who were un-operated were included as a control. In all patients, medication was reduced progressively. When the results were compared with the control group, it was seen that in 26% of the patients, both forced expiratory volume (FEV) and peak expiratory flow (PEF) increased significantly (p <05) and only modestly in 53.6% of patients (FEV, p <05 and PEF, p <05). In the remaining 20% of patients, these parameters remained however unchanged. Overall, in 80% of patients unilateral resection of the ib-SLN gave satisfactory results because it shortened the intervals and duration of asthmatic attacks, rendering thereby a reduction in medication. This minimal-invasive method helped prevent/cure asphyxias in chronic bronchial asthma without affecting cough reflex,respiratory control and phonation and it helped patients avoid severe crisis. This approach is of interest for patients with severe and/or uncontrolled bronchial asthma in settings with limited access to drug treatment.

Unilateral occipital nerve stimulation for bilateral occipital neuralgia: a case report and literature review

PubMed Central

Liu, Aijun; Jiao, Yongcheng; Ji, Huijun; Zhang, Zhiwen

2017-01-01

Objectives The aim of this study is to present a case of successful relief of bilateral occipital neuralgia (ON) using unilateral occipital nerve stimulation (ONS) and to discuss the possible underlying mechanisms. Materials and methods We present the case of a 59-year-old female patient with severe bilateral ON treated with unilateral ONS. We systematically reviewed previous studies of ONS for ON, discussing the possible mechanisms of ONS in the relief of ON. Results The patient reported complete pain relief after consistent unilateral ONS during the follow-up period. The underlying mechanisms may be linked to the relationship between pain and several brain regions, including the pons, midbrain, and periaqueductal gray. Conclusion ONS is an effective and safe option for treating ON. Future studies will be required to clarify the mechanisms by which unilateral occipital stimulation provided relief for bilateral neuralgia in this case. PMID:28176938

Unilateral occipital nerve stimulation for bilateral occipital neuralgia: a case report and literature review.

PubMed

Liu, Aijun; Jiao, Yongcheng; Ji, Huijun; Zhang, Zhiwen

2017-01-01

The aim of this study is to present a case of successful relief of bilateral occipital neuralgia (ON) using unilateral occipital nerve stimulation (ONS) and to discuss the possible underlying mechanisms. We present the case of a 59-year-old female patient with severe bilateral ON treated with unilateral ONS. We systematically reviewed previous studies of ONS for ON, discussing the possible mechanisms of ONS in the relief of ON. The patient reported complete pain relief after consistent unilateral ONS during the follow-up period. The underlying mechanisms may be linked to the relationship between pain and several brain regions, including the pons, midbrain, and periaqueductal gray. ONS is an effective and safe option for treating ON. Future studies will be required to clarify the mechanisms by which unilateral occipital stimulation provided relief for bilateral neuralgia in this case.

In Vivo Evaluation of White Matter Integrity and Anterograde Transport in Visual System After Excitotoxic Retinal Injury With Multimodal MRI and OCT

PubMed Central

Ho, Leon C.; Wang, Bo; Conner, Ian P.; van der Merwe, Yolandi; Bilonick, Richard A.; Kim, Seong-Gi; Wu, Ed X.; Sigal, Ian A.; Wollstein, Gadi; Schuman, Joel S.; Chan, Kevin C.

2015-01-01

Purpose. Excitotoxicity has been linked to the pathogenesis of ocular diseases and injuries and may involve early degeneration of both anterior and posterior visual pathways. However, their spatiotemporal relationships remain unclear. We hypothesized that the effects of excitotoxic retinal injury (ERI) on the visual system can be revealed in vivo by diffusion tensor magnetic resonance imagining (DTI), manganese-enhanced magnetic resonance imagining (MRI), and optical coherence tomography (OCT). Methods. Diffusion tensor MRI was performed at 9.4 Tesla to monitor white matter integrity changes after unilateral N-methyl-D-aspartate (NMDA)-induced ERI in six Sprague-Dawley rats and six C57BL/6J mice. Additionally, four rats and four mice were intravitreally injected with saline to compare with NMDA-injected animals. Optical coherence tomography of the retina and manganese-enhanced MRI of anterograde transport were evaluated and correlated with DTI parameters. Results. In the rat optic nerve, the largest axial diffusivity decrease and radial diffusivity increase occurred within the first 3 and 7 days post ERI, respectively, suggestive of early axonal degeneration and delayed demyelination. The optic tract showed smaller directional diffusivity changes and weaker DTI correlations with retinal thickness compared with optic nerve, indicative of anterograde degeneration. The splenium of corpus callosum was also reorganized at 4 weeks post ERI. The DTI profiles appeared comparable between rat and mouse models. Furthermore, the NMDA-injured visual pathway showed reduced anterograde manganese transport, which correlated with diffusivity changes along but not perpendicular to optic nerve. Conclusions. Diffusion tensor MRI, manganese-enhanced MRI, and OCT provided an in vivo model system for characterizing the spatiotemporal changes in white matter integrity, the eye–brain relationships and structural–physiological relationships in the visual system after ERI. PMID:26066747

Brain stem and inner ear abnormalities in children with auditory neuropathy spectrum disorder and cochlear nerve deficiency.

PubMed

Huang, B Y; Roche, J P; Buchman, C A; Castillo, M

2010-11-01

Cranial abnormalities, including CND, are common in children with ANSD. The purpose of this study was to assess whether CND is associated with brain or inner ear abnormalities in a cohort of children with ANSD. Two neuroradiologists retrospectively reviewed cranial MR imaging examinations in 103 children with ANSD. Brain, cochlear nerve, and temporal bone abnormalities were described and tabulated. Findings were stratified on the basis of the presence and laterality of CND, and differences in the presence of associated inner ear or intracranial abnormalities were assessed by using 2-tailed Fisher exact tests. CND was identified in 33.0% of children and 26.9% of ears with ANSD. Significantly more patients with bilateral CND had intracranial abnormalities than those with unilateral CND (60.0% versus 15.8%; P = .012). Forty percent of patients with bilateral CND, 0% of patients with unilateral CND, and 10.1% of those without CND demonstrated hindbrain malformations. Patients with bilateral CND were more likely to demonstrate hindbrain malformations than patients with normal nerves (P = .01) or unilateral CND (P = .004). Labyrinthine abnormalities were significantly more common in patients with bilateral CND than in those without CND (P ≤ .001). Cochlear anomalies were more common in patients with bilateral versus unilateral CND (P = .01). IAC and cochlear aperture stenosis were more common in those with unilateral and bilateral CND than those without CND (both P < .001). Cochlear and hindbrain abnormalities are significantly more common among patients with ANSD with bilateral CND compared with those with at least 1 intact cochlear nerve.

Comparison of retinal nerve fiber layer thickness in vivo and axonal transport after chronic intraocular pressure elevation in young versus older rats.

PubMed

Abbott, Carla J; Choe, Tiffany E; Burgoyne, Claude F; Cull, Grant; Wang, Lin; Fortune, Brad

2014-01-01

To compare in young and old rats longitudinal measurements of retinal nerve fiber layer thickness (RNFLT) and axonal transport 3-weeks after chronic IOP elevation. IOP was elevated unilaterally in 2- and 9.5-month-old Brown-Norway rats by intracameral injections of magnetic microbeads. RNFLT was measured by spectral domain optical coherence tomography. Anterograde axonal transport was assessed from confocal scanning laser ophthalmolscopy of superior colliculi (SC) after bilateral intravitreal injections of cholera toxin-B-488. Optic nerve sections were graded for damage. Mean IOP was elevated in both groups (young 37, old 38 mmHg, p = 0.95). RNFL in young rats exhibited 10% thickening at 1-week (50.9±8.1 µm, p<0.05) vs. baseline (46.4±2.4 µm), then 7% thinning at 2-weeks (43.0±7.2 µm, p>0.05) and 3-weeks (43.5±4.4 µm, p>0.05), representing 20% loss of dynamic range. RNFLT in old rats showed no significant change at 1-week (44.9±4.1 µm) vs. baseline (49.2±5.3 µm), but progression to 22% thinning at 2-weeks (38.0±3.7 µm, p<0.01) and 3-weeks (40.0±6.6 µm, p<0.05), representing 59% loss of dynamic range. Relative SC fluorescence intensity was reduced in both groups (p<0.001), representing 77-80% loss of dynamic range and a severe transport deficit. Optic nerves showed 75-95% damage (p<0.001). There was greater RNFL thinning in old rats (p<0.05), despite equivalent IOP insult, transport deficit and nerve damage between age groups (all p>0.05). Chronic IOP elevation resulted in severely disrupted axonal transport and optic nerve axon damage in all rats, associated with mild RNFL loss in young rats but a moderate RNFL loss in old rats despite the similar IOP insult. Hence, the glaucomatous injury response within the RNFL depends on age.

Man with a Swollen Eye: Nonspecific Orbital Inflammation in an Adult in the Emergency Department.

PubMed

Zhang, Xiao Chi; Statler, Brittney; Suner, Selim; Lloyd, Maureen; Curley, David; Migliori, Michael E

2018-07-01

Nonspecific orbital inflammation (NSOI) is a rare idiopathic ocular pathology characterized by unilateral, painful orbital swelling without identifiable infectious or systemic disorders, which can be complicated by optic nerve compromise. A 50-year-old man presented to the Emergency Department with recurring, progressive painless left eye swelling, decreased visual acuity, and binocular diplopia in the absence of trauma, infection, or known malignancy. His physical examination was notable for left-sided decreased visual acuity, an afferent pupillary defect, severe left eye proptosis and chemosis, and restricted extraocular movements; his dilatated funduscopic examination was notable for ipsilateral retinal folds within the macula, concerning for a disruption between the sclera and the retina. Ocular examination of the right eye was unremarkable. Laboratory data were unrevealing. Gadolinium-enhanced magnetic resonance imaging showed marked thickening of the left extraocular muscles associated with proptosis, dense inflammatory infiltration of the orbital fat, and characteristics consistent with perineuritis. The patient was diagnosed with NSOI with optic neuritis and admitted for systemic steroid therapy; he was discharged on hospital day 2 after receiving high-dose intravenous (i.v.) methylprednisolone with significant improvement. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: NSOI is a rare and idiopathic ocular emergency, with clinical mimicry resembling a broad spectrum of systemic diseases such as malignancy, autoimmune diseases, endocrine disorders, and infection. Initial work-up for new-onset ocular proptosis should include comprehensive laboratory testing and gadolinium-enhanced magnetic resonance imaging. Timely evaluation by an ophthalmologist is crucial to assess for optic nerve involvement. Signs of optic nerve compromise include decreased visual acuity, afferent pupillary defect, or decreased color saturation. Patients with optic nerve compromise require admission for aggressive anti-inflammatory therapy with i.v. steroids in an attempt to reduce risk of long-term visual sequelae. Our case demonstrates a severe presentation of this disorder and exhibits remarkable visual recovery after 48 h of systemic i.v. steroid treatment. Published by Elsevier Inc.

Anterior ischemic optic neuropathy in a patient with Churg-Strauss syndrome.

PubMed

Lee, Ji Eun; Lee, Seung Uk; Kim, Soo Young; Jang, Tae Won; Lee, Sang Joon

2012-12-01

We describe a patient with Churg-Strauss syndrome who developed unilateral anterior ischemic optic neuropathy. A 54-year-old man with a history of bronchial asthma, allergic rhinitis, and sinusitis presented with sudden decreased visual acuity in his right eye that had begun 2 weeks previously. The visual acuity of his right eye was 20 / 50. Ophthalmoscopic examination revealed a diffusely swollen right optic disc and splinter hemorrhages at its margin. Goldmann perimetry showed central scotomas in the right eye and fluorescein angiography showed remarkable hyperfluorescence of the right optic nerve head. Marked peripheral eosinphilia, extravascular eosinophils in a bronchial biopsy specimen, and an increased sedimentation rate supported the diagnosis of Churg-Strauss syndrome. Therapy with methylprednisolone corrected the laboratory abnormalities, improved clinical features, and preserved vision, except for the right central visual field defect. Early recognition of this systemic disease by ophthalmologists may help in preventing severe ocular complications.

Anterior Ischemic Optic Neuropathy in a Patient with Churg-Strauss Syndrome

PubMed Central

Lee, Ji Eun; Lee, Seung Uk; Kim, Soo Young; Jang, Tae Won

2012-01-01

We describe a patient with Churg-Strauss syndrome who developed unilateral anterior ischemic optic neuropathy. A 54-year-old man with a history of bronchial asthma, allergic rhinitis, and sinusitis presented with sudden decreased visual acuity in his right eye that had begun 2 weeks previously. The visual acuity of his right eye was 20 / 50. Ophthalmoscopic examination revealed a diffusely swollen right optic disc and splinter hemorrhages at its margin. Goldmann perimetry showed central scotomas in the right eye and fluorescein angiography showed remarkable hyperfluorescence of the right optic nerve head. Marked peripheral eosinphilia, extravascular eosinophils in a bronchial biopsy specimen, and an increased sedimentation rate supported the diagnosis of Churg-Strauss syndrome. Therapy with methylprednisolone corrected the laboratory abnormalities, improved clinical features, and preserved vision, except for the right central visual field defect. Early recognition of this systemic disease by ophthalmologists may help in preventing severe ocular complications. PMID:23204805

Morphological changes in the cervical intervertebral foramen dimensions with unilateral facet joint dislocation.

PubMed

Ebraheim, Nabil A; Liu, Jiayong; Ramineni, Satheesh K; Liu, Xiaochen; Xie, Joe; Hartman, Ryan G; Goel, Vijay K

2009-11-01

Many investigators have conducted studies to determine the biomechanics, causes, complications and treatment of unilateral facet joint dislocation in the cervical spine. However, there is no quantitative data available on morphological changes in the intervertebral foramen of the cervical spine following unilateral facet joint dislocation. These data are important to understand the cause of neurological compromise following unilateral facet joint dislocation. Eight embalmed human cadaver cervical spine specimens ranging from level C1-T1 were used. The nerve roots of these specimens at C5-C6 level were marked by wrapping a 0.12mm diameter wire around them. Unilateral facet dislocation at C5-C6 level was simulated by serially sectioning the corresponding ligamentous structures. A CT scan of the specimens was obtained before and after the dislocation was simulated. A sagittal plane through the centre of the pedicle and facet joint was constructed and used for measurement. The height and area of the intervertebral foramen, the facet joint space, nerve root diameter and area, and vertebral alignment both before and after dislocation were evaluated. The intervertebral foramen area changed from 50.72+/-0.88mm(2) to 67.82+/-4.77mm(2) on the non-dislocated side and from 41.39+/-1.11mm(2) to 113.77+/-5.65mm(2) on the dislocated side. The foraminal heights changed from 9.02+/-0.30mm to 10.52+/-0.50mm on the non-dislocated side and 10.43+/-0.50mm to 17.04+/-0.96mm on the dislocated side. The facet space area in the sagittal plane changed from 6.80+/-0.80mm(2) to 40.02+/-1.40mm(2) on the non-dislocated side. The C-5 anterior displacement showed a great change from 0mm to 5.40+/-0.24mm on the non-dislocated side and from 0mm to 3.42+/-0.20mm on the dislocated side. Neither of the nerve roots on either side showed a significant change in size. The lack of change in nerve root area indicates that the associated nerve injury with unilateral facet joint dislocation is probably due to distraction rather than due to direct nerve root compression.

Thermometric diagnosis of peripheral nerve injuries. Assessment of the diagnostic accuracy of a new practical technique.

PubMed

Ya'ish, F M M; Cooper, J P; Craigen, M A C

2007-07-01

The diagnosis of nerve injury using thermotropic liquid crystal temperature strips was compared blindly and prospectively against operative findings in 36 patients requiring surgical exploration for unilateral upper limb lacerations with suspected nerve injury. Thermotropic liquid crystal strips were applied to affected and non-affected segments in both hands in all subjects. A pilot study showed that a simple unilateral laceration without nerve injury results in a cutaneous temperature difference between limbs, but not within each limb. Thus, for detection of a nerve injury, comparison was made against the unaffected nerve distribution in the same hand. Receiver operating characteristic curve analysis showed that an absolute temperature difference > or = 1.0 degrees C was diagnostic of a nerve injury (area under the curve = 0.985, sensitivity = 100%, specificity = 93.8%). Thermotropic liquid crystal strip assessment is a new, reliable and objective method for the diagnosis of traumatic peripheral nerve injuries. If implemented in the acute setting, it could improve the reliability of clinical assessment and reduce the number of negative surgical explorations.

Upregulation of Ryk expression in rat dorsal root ganglia after peripheral nerve injury.

PubMed

Li, Xin; Li, Yao-hua; Yu, Shun; Liu, Yaobo

2008-10-22

To study changes of Ryk expression in dorsal root ganglia (DRG) after peripheral nerve injury, we set up an animal model of unilateral sciatic nerve lesioned rats. Changes of Ryk protein expression in DRG neurons after unilateral sciatic nerve injury were investigated by immunostaining. Changes of Ryk mRNA were also tested by semi-quantitative PCR concurrently. We found, both at the level of protein and mRNA, that Ryk could be induced in cells of ipsilateral DRG after unilateral sciatic nerve lesion. Further investigation by co-immunostaining confirmed that the Ryk-immunoreactive (Ryk-IR) cells were NeuN-immunoreactive (NeuN-IR) neurons of DRG. We also showed the pattern of Ryk induction in DRG neurons after sciatic nerve injury: the number of Ryk IR neurons peaked at 2 weeks post-lesion and decreased gradually by 3 weeks post-lesion. The proportions of different sized Ryk IR neurons were also observed and counted at various stages after nerve lesion. Analysis of Ryk mRNA by RT-PCR showed the same induction pattern as by immunostaining. Ryk mRNA was not expressed in normal or contralateral DRG, but was expressed 1, 2 and 3 weeks post-lesion in the ipsilateral DRG. Ryk mRNA levels increased slightly from 1 to 2 weeks, decreased then by 3 weeks post-lesion. These results indicate that Ryk might be involved in peripheral nerve plasticity after injury. This is a novel function apart from its well-known fundamental activity as a receptor mediating axon guidance and outgrowth.

Longitudinal Detection of Optic Nerve Head Changes by Spectral Domain Optical Coherence Tomography in Early Experimental Glaucoma

PubMed Central

He, Lin; Yang, Hongli; Gardiner, Stuart K.; Williams, Galen; Hardin, Christy; Strouthidis, Nicholas G.; Fortune, Brad; Burgoyne, Claude F.

2014-01-01

Purpose. We determined if the detection of spectral-domain optical coherence tomography (SDOCT) optic nerve head (ONH) change precedes the detection of confocal scanning laser tomography (CSLT) ONH surface, SDOCT retinal nerve fiber layer (RNFL), scanning laser perimetry (SLP), and multifocal electroretinography (mfERG) change in eight experimental glaucoma (EG) eyes. Methods. Both eyes from eight monkeys were tested at least three times at baseline, and then every 2 weeks following laser-induced chronic unilateral IOP elevation. Event and trend-based definitions of onset in the control and EG eyes for 11 SDOCT neural and connective tissue, CSLT surface, SDOCT RNFL, SLP, and mfERG parameters were explored. The frequency and timing of onset for each parameter were compared using a logrank test. Results. Maximum post-laser IOP was 18 to 42 mm Hg in the EG eyes and 12 to 20 mm Hg in the control eyes. For event- and trend-based analyses, onsets were achieved earliest and most frequently within the ONH neural and connective tissues using SDOCT, and at the ONH surface using CSLT. SDOCT ONH neural and connective tissue parameter change preceded or coincided with CSLT ONH surface change in most EG eyes. The SDOCT and SLP measures of RNFL thickness, and mfERG measures of visual function demonstrated similar onset rates, but occurred later than SDOCT ONH and CSLT surface change, and in fewer eyes. Conclusions. SDOCT ONH change detection commonly precedes or coincides with CSLT ONH surface change detection, and consistently precedes RNFLT, SLP, and mfERG change detection in monkey experimental glaucoma. PMID:24255047

Facial nerve paralysis secondary to occult malignant neoplasms.

PubMed

Boahene, Derek O; Olsen, Kerry D; Driscoll, Colin; Lewis, Jean E; McDonald, Thomas J

2004-04-01

This study reviewed patients with unilateral facial paralysis and normal clinical and imaging findings who underwent diagnostic facial nerve exploration. Study design and setting Fifteen patients with facial paralysis and normal findings were seen in the Mayo Clinic Department of Otorhinolaryngology. Eleven patients were misdiagnosed as having Bell palsy or idiopathic paralysis. Progressive facial paralysis with sequential involvement of adjacent facial nerve branches occurred in all 15 patients. Seven patients had a history of regional skin squamous cell carcinoma, 13 patients had surgical exploration to rule out a neoplastic process, and 2 patients had negative exploration. At last follow-up, 5 patients were alive. Patients with facial paralysis and normal clinical and imaging findings should be considered for facial nerve exploration when the patient has a history of pain or regional skin cancer, involvement of other cranial nerves, and prolonged facial paralysis. Occult malignancy of the facial nerve may cause unilateral facial paralysis in patients with normal clinical and imaging findings.

Optic neuritis in pediatric population: a review in current tendencies of diagnosis and management.

PubMed

Pérez-Cambrodí, Rafael José; Gómez-Hurtado Cubillana, Aránzazu; Merino-Suárez, María L; Piñero-Llorens, David P; Laria-Ochaita, Carlos

2014-01-01

Optic neuritis is an inflammation of the optic nerve and may be related to different systemic conditions. The clinical presentation of this pathology usually includes sudden loss of visual acuity (VA) which may be unilateral or bilateral, visual field restriction, pain with eye movements, dyschromatopsia, a relative afferent pupillary defect and optic disk swelling. Optic neuritis in children has specific clinical features and a better prognosis than in adulthood. Although usually appears an underlying viral disease, the main concern for practitioners is the relationship of optic neuritis with multiple sclerosis. In addition to the classical techniques as magnetic resonance imaging (MRI), current tendencies of diagnosis for eye practitioners include new imaging devices as optical coherence tomography (OCT), useful to show a thinning of the retinal fibers layer (RFL) after the inflammatory episode. Regarding the management of these patients, short-term intravenous steroid dosages seem to be the best option to treat acute attacks characterized by a very poor bilateral VA. Copyright © 2013 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

The Evaluation of Anatomic and Functional Changes in Unilateral Moderate Amblyopic Eyes Using Optical Coherence Tomography and Pupil Cycle Time.

PubMed

Kusbeci, Tuncay; Karti, Omer; Karahan, Eyyup; Oguztoreli, Mustafa

2017-12-01

To investigate whether macular anatomic structure and afferent visual system function differ among amblyopic eyes, non-amblyopic fellow eyes, and controls, using spectral-domain optical coherence tomography (SD-OCT), and pupil cycle time (PCT). This observational, cross-sectional study included 30 patients with unilateral amblyopia and 30 healthy subjects. Optical coherence tomography (OCT) and pupil cycle time (PCT) were used to evaluate patients with unilateral amblyopia and were compared with their non-amblyopic fellow eyes and age- and gender-matched healthy eyes (30 participants). The amblyopic eyes were separated into two groups: anisometropic amblyopia (n = 16) and strabismic amblyopia (n = 14). OCT maps were used to calculate central macular thickness (CMT), retinal nerve fiber layer thickness (RNFLT), and ganglion cell-inner plexiform layer (GC-IPL) thickness. The average RNFLT, GC-IPL thickness, and CMT did not show any significant differences among the amblyopic eyes, non-amblyopic fellow eyes and controls (p > 0.05, Kruskal-Wallis test). Mean PCT was 773.57 ± 64 msn in strabismic eyes, 771.25 ± 58 msn in anisometropic eyes, 778.00 ± 72 msn in non-amblyopic fellow eyes, and 774.75 ± 69 msn in control eyes. The differences among the amblyopic eyes, its fellow and control eyes were not statistically significant (p > 0.05, Kruskal-Wallis test). In this study, we investigated morphological and functional differences among amblyopic eyes, non-amblyopic fellow eyes and controls by using SD-OCT and PCT. We did not find anatomical or functional changes in amblyopic eyes.

BDNF is required for taste axon regeneration following unilateral chorda tympani nerve section.

PubMed

Meng, Lingbin; Huang, Tao; Sun, Chengsan; Hill, David L; Krimm, Robin

2017-07-01

Taste nerves readily regenerate to reinnervate denervated taste buds; however, factors required for regeneration have not yet been identified. When the chorda tympani nerve is sectioned, expression of brain-derived neurotrophic factor (BDNF) remains high in the geniculate ganglion and lingual epithelium, despite the loss of taste buds. These observations suggest that BDNF is present in the taste system after nerve section and may support taste nerve regeneration. To test this hypothesis, we inducibly deleted Bdnf during adulthood in mice. Shortly after Bdnf gene recombination, the chorda tympani nerve was unilaterally sectioned causing a loss of both taste buds and neurons, irrespective of BDNF levels. Eight weeks after nerve section, however, regeneration was differentially affected by Bdnf deletion. In control mice, there was regeneration of the chorda tympani nerve and taste buds reappeared with innervation. In contrast, few taste buds were reinnervated in mice lacking normal Bdnf expression such that taste bud number remained low. In all genotypes, taste buds that were reinnervated were normal-sized, but non-innervated taste buds remained small and atrophic. On the side of the tongue contralateral to the nerve section, taste buds for some genotypes became larger and all taste buds remained innervated. Our findings suggest that BDNF is required for nerve regeneration following gustatory nerve section. Copyright © 2017 Elsevier Inc. All rights reserved.

The Connective Tissue Components of Optic Nerve Head Cupping in Monkey Experimental Glaucoma Part 1: Global Change

PubMed Central

Yang, Hongli; Ren, Ruojin; Lockwood, Howard; Williams, Galen; Libertiaux, Vincent; Downs, Crawford; Gardiner, Stuart K.; Burgoyne, Claude F.

2015-01-01

Purpose To characterize optic nerve head (ONH) connective tissue change within 21 monkey experimental glaucoma (EG) eyes, so as to identify its principal components. Methods Animals were imaged three to five times at baseline then every 2 weeks following chronic unilateral IOP elevation, and euthanized early through end-stage confocal scanning laser tomographic change. Optic nerve heads were serial-sectioned, three-dimensionally (3D) reconstructed, delineated, and quantified. Overall EG versus control eye differences were assessed by general estimating equations (GEE). Significant, animal-specific, EG eye change was required to exceed the maximum physiologic intereye differences in six healthy animals. Results Overall EG eye change was significant (P < 0.0026) and animal-specific EG eye change most frequent, for five phenomena (number of EG eyes and range of animal-specific change): posterior laminar deformation (21, −29 to −437 μm), laminar thickening (11, 20–73 μm) and thinning (3, −23 to −31 μm), scleral canal expansion (17, 20–139 μm), outward anterior (16, −16 to −124 μm) and posterior (17, −22 to −279 μm) laminar insertion migration, and peripapillary scleral bowing (11, 21–77 μm). Experimental glaucoma versus control eye laminar thickness differences were bimodal in behavior, being thickened in most EG eyes demonstrating the least deformation and less thickened or thinned in most EG eyes demonstrating the greatest deformation. Conclusions Our postmortem studies retrospectively identify five connective tissue components of ONH “cupping” in monkey EG which serve as targets for longitudinally staging and phenotyping ONH connective tissue alteration within all forms of monkey and human optic neuropathy. PMID:26641545

Space flight-associated neuro-ocular syndrome (SANS).

PubMed

Lee, Andrew G; Mader, Thomas H; Gibson, C Robert; Brunstetter, Tyson J; Tarver, William J

2018-03-12

Interesting novel and somewhat perplexing physiologic and pathologic neuro-ocular findings have been documented in astronauts during and after long duration space flight (LDSF). These findings collectively have been termed the "space flight-associated neuro-ocular syndrome" (SANS). The National Aeronautics and Space Administration (NASA) in the United States has meticulously and prospectively documented the clinical, ultrasound, optical coherence tomography imaging, and radiographic findings of SANS including unilateral and bilateral optic disc edema, globe flattening, choroidal and retinal folds, hyperopic refractive error shifts, and nerve fiber layer infarcts (i.e., cotton wool spots). NASA and collaborating researchers continue to study SANS in preparation for future manned missions to space, including continued trips to the ISS, a return to the moon, or perhaps new voyages to the asteroid belt, or the planet, Mars.

Facial neuropathy with imaging enhancement of the facial nerve: a case report

PubMed Central

Mumtaz, Sehreen; Jensen, Matthew B

2014-01-01

A young women developed unilateral facial neuropathy 2 weeks after a motor vehicle collision involving fractures of the skull and mandible. MRI showed contrast enhancement of the facial nerve. We review the literature describing facial neuropathy after trauma and facial nerve enhancement patterns with different causes of facial neuropathy. PMID:25574155

Herpes zoster: A clinicocytopathological insight.

PubMed

Shah, Snehal; Singaraju, Sasidhar; Einstein, A; Sharma, Ashish

2016-01-01

Herpes zoster or shingles is reactivation of the varicella zoster virus that had entered the cutaneous nerve endings during an earlier episode of chicken pox traveled to the dorsal root ganglia and remained in a latent form. This condition is characterized by occurrence of multiple, painful, unilateral vesicles and ulceration which shows a typical single dermatome involvement. In this case report, we present a patient with herpes zoster involving the mandibular division of the trigeminal nerve, with unilateral vesicles over the right side of lower third of face along the trigeminal nerve tract, with intraoral involvement of buccal mucosa, labial mucosa and the tongue of the same side. Cytopathology revealed classic features of herpes infection including inclusion bodies, perinuclear halo and multinucleated cells.

Delayed presentation of traumatic facial nerve (CN VII) paralysis.

PubMed

Napoli, Anthony M; Panagos, Peter

2005-11-01

Facial nerve paralysis (Cranial Nerve VII, CN VII) can be a disfiguring disorder with profound impact upon the patient. The etiology of facial nerve paralysis may be congenital, iatrogenic, or result from neoplasm, infection, trauma, or toxic exposure. In the emergency department, the most common cause of unilateral facial paralysis is Bell's palsy, also known as idiopathic facial paralysis (IFP). We report a case of delayed presentation of unilateral facial nerve paralysis 3 days after sustaining a traumatic head injury. Re-evaluation and imaging of this patient revealed a full facial paralysis and temporal bone fracture extending into the facial canal. Because cranial nerve injuries occur in approximately 5-10% of head-injured patients, a good history and physical examination is important to differentiate IFP from another etiology. Newer generation high-resolution computed tomography (CT) scans are commonly demonstrating these fractures. An understanding of this complication, appropriate patient follow-up, and early involvement of the Otolaryngologist is important in management of these patients. The mechanism as well as the timing of facial nerve paralysis will determine the proper evaluation, consultation, and management for the patient. Patients with total or immediate paralysis as well as those with poorly prognostic audiogram results are good candidates for surgical repair.

Current concepts in the diagnosis, pathogenesis and management of nonarteritic anterior ischaemic optic neuropathy.

PubMed

Miller, N R; Arnold, A C

2015-01-01

Nonarteritic anterior ischaemic optic neuropathy (NAION) is the most common acute optic neuropathy in patients over the age of 50 and is the second most common cause of permanent optic nerve-related visual loss in adults after glaucoma. Patients typically present with acute, painless, unilateral loss of vision associated with a variable visual field defect, a relative afferent pupillary defect, a swollen, hyperaemic optic disc, and one or more flame-shaped peripapillary retinal haemorrhages. The pathogenesis of this condition is unknown, but it occurs primarily in patients with structurally small optic discs that have little or no cup and a variety of underlying vascular disorders that may or may not be known at the time of visual loss. There is no consistently beneficial medical or surgical treatment for the condition, but there are now animal models that allow testing of various potential therapies. About 40% of patients experience spontaneous improvement in visual acuity. Patients in whom NAION occurs in one eye have a 15-19% risk of developing a similar event in the opposite eye over the subsequent 5 years.

Current concepts in the diagnosis, pathogenesis and management of nonarteritic anterior ischaemic optic neuropathy

PubMed Central

Miller, N R; Arnold, A C

2015-01-01

Nonarteritic anterior ischaemic optic neuropathy (NAION) is the most common acute optic neuropathy in patients over the age of 50 and is the second most common cause of permanent optic nerve-related visual loss in adults after glaucoma. Patients typically present with acute, painless, unilateral loss of vision associated with a variable visual field defect, a relative afferent pupillary defect, a swollen, hyperaemic optic disc, and one or more flame-shaped peripapillary retinal haemorrhages. The pathogenesis of this condition is unknown, but it occurs primarily in patients with structurally small optic discs that have little or no cup and a variety of underlying vascular disorders that may or may not be known at the time of visual loss. There is no consistently beneficial medical or surgical treatment for the condition, but there are now animal models that allow testing of various potential therapies. About 40% of patients experience spontaneous improvement in visual acuity. Patients in whom NAION occurs in one eye have a 15–19% risk of developing a similar event in the opposite eye over the subsequent 5 years. PMID:24993324

Intraorbital foreign body projectile as a consideration for unilateral pupillary defect

PubMed Central

2012-01-01

Intraorbital foreign bodies are frequently the result of high-velocity injuries with varying clinical presentations. The resultant diagnosis, management, and outcome depend on the type of foreign body present, anatomical location, tissue disruption, and symptomatology. A patient who presented to the Emergency Department with a large intraorbital foreign body projectile that was not evident clinically, but found incidentally on computed tomography and subsequent plain films is reported. The emergency room physician needs to be aware of the differential diagnosis of a unilateral irregular pupil with or without visual acuity changes. The differential diagnosis for any trauma patient with an irregular pupil with significant visual loss must include intraorbital foreign body and associated injury to the optic nerve directly or via orbital compartment syndrome secondary to hemorrhage and/or edema. Patients with significantly decreased visual acuity may benefit from emergent surgical intervention. In patients with intact visual acuity, the patient must be monitored closely for any visual changes as this may require emergent surgical intervention. PMID:22390406

Optic Nerve Lymphoma. Report of Two Cases and Review of the Literature

PubMed Central

Kim, Jennifer L.; Mendoza, Pia; Rashid, Alia; Hayek, Brent; Grossniklaus, Hans E.

2014-01-01

Lymphoma may involve the optic nerve as isolated optic nerve lymphoma or in association with CNS or systemic lymphoma. We present two biopsy-proven non-Hodgkin lymphomas of the optic nerve and compare our findings with previously reported cases. We discuss the mechanism of metastasis, classification of optic nerve involvement, clinical features, radiologic findings, optic nerve biopsy indications and techniques, histologic features, and treatments. We propose a classification system of optic nerve lymphoma: isolated optic nerve involvement, optic nerve involvement with CNS disease, optic nerve involvement with systemic disease, and optic nerve involvement with primary intraocular lymphoma. Although it is an uncommon cause of infiltrative optic neuropathy, optic nerve metastasis should be considered in patients with a history of lymphoma. The recommended approach to a patient with presumed optic nerve lymphoma includes neuroimaging, and cerebrospinal fluid evaluation as part of the initial work-up, then judicious use of optic nerve biopsy, depending on the clinical situation. PMID:25595061

[Amyotrophic neuralgia associated with bilateral phrenic paralysis treated with non-invasive mechanical ventilation].

PubMed

García García, María Del Carmen; Hernández Borge, Jacinto; Antona Rodríguez, María José; Pires Gonçalves, Pedro; García García, Gema

2015-09-07

Amyotrophic neuralgia is an uncommon neuropathy characterized by severe unilateral shoulder pain. Isolated or concomitant involvement of other peripheral motor nerves depending on the brachial plexus such as phrenic or laryngeal nerves is unusual(1). Its etiology is unknown, yet several explanatory factors have been proposed. Phrenic nerve involvement, either unilateral or bilateral, is exceedingly rare. Diagnosis relies on anamnesis, functional and imaging investigations and electromyogram. We report the case of a 48-year-old woman with a past history of renal transplantation due to proliferative glomerulonephritis with subsequent transplant rejection, who was eventually diagnosed with amyotrophic neuralgia with bilateral phrenic involvement, and who required sustained non-invasive mechanical ventilation. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

Diplopia as the primary presentation of foodborne botulism.

PubMed

Khakshoor, Hamid; Moghaddam, Ali Akbar Saber; Vejdani, Amir Hossein; Armstrong, Blair K; Moshirfar, Majid

2012-05-01

Foodborne botulism is a serious condition caused by Clostridium botulinum neurotoxin. Clinically, botulism presents as bilateral cranial nerve neuropathy and descending paralysis. We report a unique presentation of botulism to remind clinicians of this potentially fatal condition. In this observational case report initial evaluation showed only esodeviation. This progressed to unilateral cranial nerve six (CN VI) paresis along with systemic signs. Clinical diagnosis was made based on in-depth history and concurrent symptoms in three other patients. Foodborne botulism presenting as diplopia and unilateral motility deficits is rare and can represent a diagnostic and therapeutic challenge to the ophthalmologist.

Diplopia as the primary presentation of foodborne botulism

PubMed Central

Khakshoor, Hamid; Moghaddam, Ali Akbar Saber; Vejdani, Amir Hossein; Armstrong, Blair K.; Moshirfar, Majid

2012-01-01

Foodborne botulism is a serious condition caused by Clostridium botulinum neurotoxin. Clinically, botulism presents as bilateral cranial nerve neuropathy and descending paralysis. We report a unique presentation of botulism to remind clinicians of this potentially fatal condition. In this observational case report initial evaluation showed only esodeviation. This progressed to unilateral cranial nerve six (CN VI) paresis along with systemic signs. Clinical diagnosis was made based on in-depth history and concurrent symptoms in three other patients. Foodborne botulism presenting as diplopia and unilateral motility deficits is rare and can represent a diagnostic and therapeutic challenge to the ophthalmologist. PMID:22993467

Unilateral Punctate Keratitis Secondary to Wallenberg Syndrome

PubMed Central

Boto, Ana; Del Hierro, Almudena; Capote, Maria; Noval, Susana; Garcia, Amanda; Santiago, Susana

2014-01-01

We studied three patients who developed left unilateral punctate keratitis after suffering left-sided Wallenberg Syndrome. A complex evolution occurred in two of them. In all cases, neurophysiological studies showed damage in the trigeminal sensory component at the bulbar level. Corneal involvement secondary to Wallenberg syndrome is a rare cause of unilateral superficial punctate keratitis. The loss of corneal sensitivity caused by trigeminal neuropathy leads to epithelial erosions that are frequently unobserved by the patient, resulting in a high risk of corneal-ulcer development with the possibility of superinfection. Neurophysiological studies can help to locate the anatomical level of damage at the ophthalmic branch of the trigeminal nerve, confirming the suspected etiology of stroke, and demonstrating that prior vascular involvement coincides with the location of trigeminal nerve damage. In some of these patients, oculofacial pain is a distinctive feature. PMID:24882965

Constriction of the buccal branch of the facial nerve produces unilateral craniofacial allodynia.

PubMed

Lewis, Susannah S; Grace, Peter M; Hutchinson, Mark R; Maier, Steven F; Watkins, Linda R

2017-08-01

Despite pain being a sensory experience, studies of spinal cord ventral root damage have demonstrated that motor neuron injury can induce neuropathic pain. Whether injury of cranial motor nerves can also produce nociceptive hypersensitivity has not been addressed. Herein, we demonstrate that chronic constriction injury (CCI) of the buccal branch of the facial nerve results in long-lasting, unilateral allodynia in the rat. An anterograde and retrograde tracer (3000MW tetramethylrhodamine-conjugated dextran) was not transported to the trigeminal ganglion when applied to the injury site, but was transported to the facial nucleus, indicating that this nerve branch is not composed of trigeminal sensory neurons. Finally, intracisterna magna injection of interleukin-1 (IL-1) receptor antagonist reversed allodynia, implicating the pro-inflammatory cytokine IL-1 in the maintenance of neuropathic pain induced by facial nerve CCI. These data extend the prior evidence that selective injury to motor axons can enhance pain to supraspinal circuits by demonstrating that injury of a facial nerve with predominantly motor axons is sufficient for neuropathic pain, and that the resultant pain has a neuroimmune component. Copyright © 2016 Elsevier Inc. All rights reserved.

Bilateral LMAN lesions cancel differences in HVC neuronal recruitment induced by unilateral syringeal denervation. Lateral magnocellular nucleus of the anterior neostriatum.

PubMed

Wilbrecht, L; Petersen, T; Nottebohm, F

2002-12-01

Twenty-six-day-old male zebra finches received (1) unilateral section of their tracheosyringeal nerve, (2) bilateral lesions of the lateral magnocellular nucleus of the anterior neostriatum (LMAN), and (3) both operations. All birds were kept with an adult, singing male as a tutor until day 65. Tracheo-syringeal nerve-cut birds were able to imitate this model, but LMAN-lesioned birds were not. Bromodeoxyuridine, a marker of cell division, was injected intramuscularly during post-hatching days 61-65 and all birds were killed at 91 days of age. The number of bromodeoxyuridine+ neurons in the high vocal center of the tracheosyringeal-cut birds was twice as high in the intact as in the nerve cut side. This asymmetry disappeared when nerve section was combined with bilateral LMAN lesions. The latter operation, by itself, had no effect on new neuron counts. We suggest that the single nerve cut produced a hemispheric asymmetry in learning, reflected in new neuron recruitment, which disappeared when LMAN lesions blocked learning.

Sonographic evaluation of sciatic nerves in patients with unilateral sciatica.

PubMed

Kara, Murat; Özçakar, Levent; Tiftik, Tülay; Kaymak, Bayram; Özel, Sumru; Akkuş, Selami; Akinci, Ayşen

2012-09-01

To evaluate the sciatic nerves of patients with unilateral sciatica by using an ultrasound, and to determine whether ultrasonographic findings were related to clinical and electrophysiologic parameters. Cross-sectional study. Physical medicine and rehabilitation departments of a university hospital and a rehabilitation hospital. Consecutive patients (N=30; 10 men, 20 women) with complaints of low back pain and unilateral sciatica of more than 1 month of duration were enrolled. Not applicable. All patients underwent a substantial clinical assessment, and they were also evaluated by electromyogram and magnetic resonance imaging. Pain was evaluated by a visual analog scale and the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) Scale. A linear array probe (7.5-12MHz) was used to scan sciatic nerves bilaterally in the prone position. Sciatic nerve diameters-thickness (short axis) and width (long axis)-and cross-sectional areas were measured bilaterally at the same levels, proximal to the bifurcation and midthigh. The values pertaining to the unaffected limbs were taken as controls. When compared with the unaffected sides, mean values for sciatic nerve measurements-long axis at bifurcation level (P=.017) and cross-sectional area at midthigh level (P=.005)-were significantly larger on the affected sides. Swelling ratios negatively correlated with symptom duration (r=-.394, P=.038) and LANSS scores (r=-.451, P=.016) at only midthigh level. Sciatic nerves seem to be enlarged on the side of sciatica in patients with low back pain. Our preliminary results may provide insight into better understanding the lower limb radiating pain in this group of patients. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Phrenic and hypoglossal nerve activity during respiratory response to hypoxia in 6-OHDA unilateral model of Parkinson's disease.

PubMed

Andrzejewski, Kryspin; Budzińska, Krystyna; Kaczyńska, Katarzyna

2017-07-01

Parkinson's disease (PD) patients apart from motor dysfunctions exhibit respiratory disturbances. Their mechanism is still unknown and requires investigation. Our research was designed to examine the activity of phrenic (PHR) and hypoglossal (HG) nerves activity during a hypoxic respiratory response in the 6-hydroxydopamine (6-OHDA) model of PD. Male adult Wistar rats were injected unilaterally with 6-OHDA (20μg) or the vehicle into the right medial forebrain bundle (MFB). Two weeks after the surgery the activity of the phrenic and hypoglossal nerve was registered in anesthetized, vagotomized, paralyzed, and mechanically ventilated rats under normoxic and hypoxic conditions. Lesion effectiveness was confirmed by the cylinder test, performed before the MFB injection and 14days after, before the respiratory experiment. 6-OHDA lesioned animals showed a significant increase in normoxic inspiratory time. Expiratory time and total time of the respiratory cycle were prolonged in PD rats after hypoxia. The amplitude of the PHR activity and its minute activity were increased in comparison to the sham group at recovery time and during 30s of hypoxia. The amplitude of the HG activity was increased in response to hypoxia in 6-OHDA lesioned animals. The degeneration of dopaminergic neurons decreased the pre-inspiratory/inspiratory ratio of the hypoglossal burst amplitude during and after hypoxia. Unilateral MFB lesion changed the activity of the phrenic and hypoglossal nerves. The altered pre-inspiratory hypoglossal nerve activity indicates modifications to the central mechanisms controlling the activity of the HG nerve and may explain respiratory disorders seen in PD, i.e. apnea. Copyright © 2017 Elsevier Inc. All rights reserved.

Trigeminal Proprioception Evoked by Strong Stretching of the Mechanoreceptors in Müller's Muscle Induces Reflex Contraction of the Orbital Orbicularis Oculi Slow-Twitch Muscle Fibers.

PubMed

Matsuo, Kiyoshi; Ban, Ryokuya; Ban, Midori; Yuzuriha, Shunsuke

2014-01-01

The mixed orbicularis oculi muscle lacks an intramuscular proprioceptive system such as muscle spindles, to induce reflex contraction of its slow-twitch fibers. We evaluated whether the mechanoreceptors in Müller's muscle function as extrinsic mechanoreceptors to induce reflex contraction of the slow-twitch fibers of the orbicularis oculi in addition to those of the levator and frontalis muscles. We evaluated in patients with aponeurosis-disinserted blepharoptosis whether strong stretching of the mechanoreceptors in Müller's muscle from upgaze with unilateral lid load induced reflex contraction of the orbicularis oculi slow-twitch fibers and whether anesthesia of Müller's muscle precluded the contraction. We compared the electromyographic responses of the bilateral orbicularis oculi muscles to unilateral intraoperative direct stimulation of the trigeminal proprioceptive nerve with those to unilateral transcutaneous electrical stimulation of the supraorbital nerve. Upgaze with a unilateral 3-g lid load induced reflex contraction of the bilateral orbicularis oculi muscles with ipsilateral dominance. Anesthesia of Müller's muscle precluded the reflex contraction. The orbicularis oculi reflex evoked by stimulation of the trigeminal proprioceptive nerve differed from that by electrical stimulation of the supraorbital nerve in terms of the intensity of current required to induce the reflex, the absence of R1, and duration. The mechanoreceptors in Müller's muscle functions as an extramuscular proprioceptive system to induce reflex contraction of the orbital orbicularis oculi slow-twitch fibers. Whereas reflex contraction of the pretarsal orbicularis fast-twitch fibers functions in spontaneous or reflex blinking, that of the orbital orbicularis oculi slow-twitch fibers may factor in grimacing and blepharospasm.

Trigeminal Proprioception Evoked by Strong Stretching of the Mechanoreceptors in Müller's Muscle Induces Reflex Contraction of the Orbital Orbicularis Oculi Slow-Twitch Muscle Fibers

PubMed Central

Ban, Ryokuya; Ban, Midori; Yuzuriha, Shunsuke

2014-01-01

Objective: The mixed orbicularis oculi muscle lacks an intramuscular proprioceptive system such as muscle spindles, to induce reflex contraction of its slow-twitch fibers. We evaluated whether the mechanoreceptors in Müller's muscle function as extrinsic mechanoreceptors to induce reflex contraction of the slow-twitch fibers of the orbicularis oculi in addition to those of the levator and frontalis muscles. Methods: We evaluated in patients with aponeurosis-disinserted blepharoptosis whether strong stretching of the mechanoreceptors in Müller's muscle from upgaze with unilateral lid load induced reflex contraction of the orbicularis oculi slow-twitch fibers and whether anesthesia of Müller's muscle precluded the contraction. We compared the electromyographic responses of the bilateral orbicularis oculi muscles to unilateral intraoperative direct stimulation of the trigeminal proprioceptive nerve with those to unilateral transcutaneous electrical stimulation of the supraorbital nerve. Results: Upgaze with a unilateral 3-g lid load induced reflex contraction of the bilateral orbicularis oculi muscles with ipsilateral dominance. Anesthesia of Müller's muscle precluded the reflex contraction. The orbicularis oculi reflex evoked by stimulation of the trigeminal proprioceptive nerve differed from that by electrical stimulation of the supraorbital nerve in terms of the intensity of current required to induce the reflex, the absence of R1, and duration. Conclusions: The mechanoreceptors in Müller's muscle functions as an extramuscular proprioceptive system to induce reflex contraction of the orbital orbicularis oculi slow-twitch fibers. Whereas reflex contraction of the pretarsal orbicularis fast-twitch fibers functions in spontaneous or reflex blinking, that of the orbital orbicularis oculi slow-twitch fibers may factor in grimacing and blepharospasm. PMID:25210572

Peripheral nerve blocks for the treatment of short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) during pregnancy.

PubMed

Yalın, Osman Özgür; Uludüz, Derya; Özge, Aynur

2018-01-01

Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) is a rare, primary headache syndrome, which is classified as a subtype of trigeminal autonomic cephalalgias. Although SUNCT is usually refractory to treatment, several antiepileptic drugs have recently shown promising results for its treatment. However, there is a lack of evidence regarding the course of SUNCT during pregnancy and the available treatment options. Here, we present a 30-week pregnant female with SUNCT who was successfully treated with infra- and supraorbital nerve blocks. Headache attacks completely diminished after the injection, and recurrence was not observed. Although lamotrigine may be relatively safe in pregnant patients with SUNCT attacks, peripheral nerve block may be a feasible technique and can be considered as a safe and effective treatment option. This is the first SUNCT case in the literature that was successfully treated with infra- and supraorbital nerve blocks during pregnancy.

Optic neuropathy causing vertical unilateral hemianopsia after pars plana vitrectomy for a macular hole: A case report.

PubMed

Kawashima, Hirohiko; Nagai, Norihiro; Shinoda, Hajime; Tsubota, Kazuo; Ozawa, Yoko

2018-04-01

Recent progress in medical technology has resulted in improved surgical outcomes of pars plana vitrectomy (PPV); with microincision systems, the incidence of procedure-related complications during surgery has been reduced. However, unpredictable visual field defects after PPV remain an unresolved issue. A few reports have shown that damage to the retinal neurofibers owing to dry-up during air/fluid exchange or retinal neurotoxicity of the dye used to visualize the internal limiting membrane (ILM), as well as unintentional removal of retinal neurofibers during ILM peeling, are responsible for such visual field disorders. In this report, we present a case of extensive visual field defect due to optic neuropathy exhibiting vertical hemianopsia after PPV. A 50-year-old woman underwent PPV and cataract surgery for a macular hole and mild cataract under retrobulbar anesthesia with 3.5 mL of xylocaine. At the time of opening an infusion cannula for PPV, the intraocular lens was herniating, with an acute increase in pressure from the posterior eyeball; thus, intraocular pressure configuration level had to be decreased from the default level, whereas the other procedures including 20% SF6 injection were performed without any modification. The macular hole was closed postoperatively. However, the patient experienced nasal hemianopsia, which turned out to be optic neuropathy, as assessed via electric physiological examinations. The pattern of the visual field defect was not typical for glaucoma or anterior ischemic optic neuropathy. Her optic nerve head was pale at the temporal side soon after the surgery, and her blood pressure was low, suggesting that there may have been a congestion of the optic nerve feeder vessels because of the relatively high pressure in the orbit. The space occupancy with xylocaine and extensively stretched and plumped out eye ball with infusion during PPV may have pressed the surrounding tissue of the optic nerve and the feeder vessels. PPV is safe for most patients; however, individual variations in local and/or systemic conditions may cause complications. Future studies to optimize the surgical condition for each individual patient may be warranted.

Choroidal thickness in traumatic optic neuropathy.

PubMed

Lee, Ju-Yeun; Eo, Doo-Ri; Park, Kyung-Ah; Oh, Sei Yeul

2017-12-01

To examine the choroidal thickness in patients with indirect traumatic optic neuropathy (TON) Methods: Patients with unilateral traumatic optic neuropathy over a period of 4 years were included in this study. Horizontal and vertical enhanced-depth imaging (EDI) from spectral-domain optical coherence tomography (SD-OCT) scans of the fovea were obtained in patients with unilateral TON within 2 weeks of injury. The main outcome measure was the choroidal thickness at nine locations. The choroidal thickness was compared between affected and unaffected eyes in the TON group, and the mean difference in the choroidal thickness in both eyes was compared between TON and control groups. A total of 16 patients and 20 control subjects were included. The choroidal thickness at horizontal, vertical and average subfoveal, inner temporal, and outer inferior locations was significantly thicker (13-23%) in affected eyes than in unaffected fellow eyes (p = 0.042, 0.046, 0.024, 0.013, 0.018, and 0.027, respectively). The mean difference value between choroidal thickness measurements in both eyes was significantly larger in the TON group than in the control group at the horizontal, vertical and average subfoveal, inner temporal, inner nasal, inner superior, inner inferior, and outer superior locations (p = 0.001, 0.011, <0.001, 0.001, 0.033, 0.014, 0.011, and 0.014, respectively). The choroidal thickness at subfoveal locations showed no statistical difference between TON and control eyes (p > 0.05). Eyes affected by TON showed a regionally thicker choroid than unaffected fellow eye. This thick choroid might be due to impaired blood circulation and vascular remodeling of the optic nerve head and choroid. These results help to better understand the pathophysiology of TON.

A patient with bilateral facial palsy associated with hypertension and chickenpox: learning points.

PubMed

Al-Abadi, Eslam; Milford, David V; Smith, Martin

2010-11-26

Bilateral facial nerve paralysis is an uncommon presentation and even more so in children. There are reports of different causes of bilateral facial nerve palsy. It is well-established that hypertension and chickenpox causes unilateral facial paralysis and the importance of checking the blood pressure in children with facial nerve paralysis cannot be stressed enough. The authors report a boy with bilateral facial nerve paralysis in association with hypertension and having recently recovered from chickenpox. The authors review aspects of bilateral facial nerve paralysis as well as hypertension and chickenpox causing facial nerve paralysis.

A patient with bilateral facial palsy associated with hypertension and chickenpox: learning points

PubMed Central

Al-Abadi, Eslam; Milford, David V; Smith, Martin

2010-01-01

Bilateral facial nerve paralysis is an uncommon presentation and even more so in children. There are reports of different causes of bilateral facial nerve palsy. It is well-established that hypertension and chickenpox causes unilateral facial paralysis and the importance of checking the blood pressure in children with facial nerve paralysis cannot be stressed enough. The authors report a boy with bilateral facial nerve paralysis in association with hypertension and having recently recovered from chickenpox. The authors review aspects of bilateral facial nerve paralysis as well as hypertension and chickenpox causing facial nerve paralysis. PMID:22797481

Metastatic breast carcinoma presenting as unilateral pulsatile tinnitus: a case report.

PubMed

Moore, Andrew; Cunnane, Max; Fleming, Jason C

2015-02-01

Pulsatile tinnitus is a rare symptom, yet it may herald life-threatening pathology in the absence of other symptoms or signs. Pulsatile tinnitus tends to imply a vascular cause, but metastatic disease also can present in this way. Clinicians should therefore adopt a specific diagnostic algorithm for pulsatile tinnitus and always consider the possibility of metastatic disease. A history of malignant disease and new cranial nerve palsies should raise clinical suspicion for skull base metastases. We describe the case of a 63-year-old woman presenting with unilateral subjective pulsatile tinnitus and a middle ear mass visible on otoscopy. Her background included the diagnosis of idiopathic unilateral vagal and hypoglossal nerve palsies 4 years previously, with normal magnetic resonance imaging (MRI). Repeat MRI and computed tomography imaging were consistent with metastatic breast carcinoma. This case raises important questions about imaging protocols and the role of serial scanning in patients at high risk of metastatic disease.

The masseteric nerve: a versatile power source in facial animation techniques.

PubMed

Bianchi, B; Ferri, A; Ferrari, S; Copelli, C; Salvagni, L; Sesenna, E

2014-03-01

The masseteric nerve has many advantages including low morbidity, its proximity to the facial nerve, the strong motor impulse, its reliability, and the fast reinnervation that is achievable in most patients. Reinnervation of a neuromuscular transplant is the main indication for its use, but it has been used for the treatment of recent facial palsies with satisfactory results. We have retrospectively evaluated 60 patients who had facial animation procedures using the masseteric nerve during the last 10 years. The patients included those with recent, and established or congenital, unilateral and bilateral palsies. The masseteric nerve was used for coaptation of the facial nerve either alone or in association with crossfacial nerve grafting, or for the reinnervation of gracilis neuromuscular transplants. Reinnervation was successful in all cases, the mean (range) time being 4 (2-5) months for facial nerve coaptation and 4 (3-7) months for neuromuscular transplants. Cosmesis was evaluated (moderate, n=10, good, n=30, and excellent, n=20) as was functional outcome (no case of impairment of masticatory function, all patients able to smile, and achievement of a smile independent from biting). The masseteric nerve has many uses, including in both recent, and established or congenital, cases. In some conditions it is the first line of treatment. The combination of combined techniques gives excellent results in unilateral palsies and should therefore be considered a valid option. Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

[Proven and innovative operative techniques for reanimation of the paralyzed face].

PubMed

Frey, M; Michaelidou, M; Tzou, C-H J; Hold, A; Pona, I; Placheta, E

2010-04-01

This overview on the currently most effective reconstructive techniques for reanimation of the unilaterally or bilaterally paralysed face includes all important techniques of neuromuscular reconstruction as well as of supplementary static procedures, which contribute significantly to the efficiency and quality of the functional overall result. Attention is paid to the best indications at the best time since onset of the facial palsy, depending on the age of the patient, the cause of the lesion, and the compliance of the patient for a long-lasting and complex rehabilitation programme. Immediate neuromuscular reconstruction of mimic function is favourable by nerve suture or nerve grafting of the facial nerve, or by using the contralateral healthy facial nerve via cross-face nerve grafting as long as the time since onset of the irreversible palsy is short enough that the paralysed mimic muscles can still be reinnervated. For the most frequent indication, the unilateral irreversible and complete palsy, a three-stage concept is described including cross-face nerve grafting, free functional gracilis muscle transplantation, and several supplementary procedures. In patients with limited life expectancy, transposition of the masseteric muscles is favoured. Bilateral facial palsy is treated by bilateral free gracilis muscle transplantation with the masseteric nerve branches for motor reinnervation. Functional upgrading in incomplete lesions is achieved by cross-face nerve grafting with distal end-to-side neurorrhaphy or by functional muscle transplantation with ipsilateral facial nerve supply. (c) Georg Thieme Verlag KG Stuttgart-New York.

Analysis of Genetic Mutations in a Cohort of Hereditary Optic Neuropathy in Shanghai, China.

PubMed

Gan, Dekang; Li, Mengwei; Wu, Jihong; Sun, Xinghuai; Tian, Guohong

2017-01-01

To evaluate the clinical classification and characteristics of hereditary optic neuropathy patients in a single center in China. Retrospective case study. Patients diagnosed with hereditary optic neuropathy between January 2014 and December 2015 in the neuro-ophthalmology division in Shanghai Eye and ENT Hospital of Fudan University were recruited. Clinical features as well as visual field, brain/orbital MRI, and spectrum domain optical coherence tomography (SD-OCT) were analyzed. Eighty-two patients diagnosed by gene test were evaluated, including 66 males and 16 females. The mean age of the patients was 19.4 years (range, 5-46 years). A total of 158 eyes were analyzed, including 6 unilateral, 61 bilateral, and 15 sequential. The median duration of the disease was 0.5 year (range, 0.1-20 years). Genetic test identified 68 patients with Leber hereditary optic neuropathy, 9 with dominant optic neuropathy, and 2 with a Wolfram gene mutation. There was also one case of hereditary spastic paraplegia, spinocerebellar ataxia, and polymicrogyria with optic nerve atrophy, respectively. Leber hereditary optic neuropathy is the most common detected type of hereditary optic neuropathy in Shanghai, China. The detection of other autosomal mutations in hereditary optic neuropathy is limited by the currently available technique.

[Immediate recurrent laryngeal nerve reconstruction in the treatment of thyroid cancer invading the recurrent laryngeal nerve].

PubMed

Feng, Yun; Yang, Dazhang; Liu, Dandan; Chen, Jian; Bi, Qingling; Luo, Keqiang

2014-08-01

To explore the application of immediate recurrent laryngeal nerve reconstruction in the treatment of thyroid cancer invading the recurrent laryngeal nerve. Ten patients with thyroid cancer invading unilateral recurrent laryngeal nerve underwent radical surgery and immediate recurrent laryngeal nerve reconstruction. The reconstructive surgical approach included recurrent laryngeal nerve decompression surgery, end-to-end anastomosis of the recurrent laryngeal nerve, anastomosis of ansa cervicalis nerve to the recurrent laryngeal nerve, and nerve-muscle pedicle (NMP) technique. Among the ten patients, one underwent nerve decompression, one underwent end-to-end anastomosis of the recurrent laryngeal nerve, seven had anastomosis of ansa cervicalis to recurrent laryngeal nerve, and one case had anastomosis of ansa cervicalis to recurrent laryngeal nerve combined with nerve-muscle pedicle (NMP) technique. The effect of surgery was evaluated by videolaryngoscopy, maximum phonation time (MPT), phonation efficiency index (PEI) and voice assessment. T-test was used in the statistical analysis. All of the 10 patients had no complications including tumor recurrence and hypoparathyroidism after the surgery. Their hoarseness symptoms were improved, and the patients returned to normal or near-normal voice. Postoperative videolaryngoscopy showed that paralyzed vocal cord returned to normal muscle tone and volume, and the vocal cord vibration and mucosal wave were symmetric and the patients got good glottal closure. The pre- and post-operative maximum phone times of the patients were (4.52 ± 0.89) s and (11.91 ± 1.87) s, respectively (P < 0.01). The pre- and post-operative phonation efficiency indices were (1.37 ± 0.43) s/L and (4.02 ± 1.33) s/L, respectively (P < 0.05). In patients with thyroid cancer invading unilateral recurrent laryngeal nerve, immediate recurrent laryngeal nerve reconstruction following radical surgery of thyroid cancer can effectively achieve recovery in phonation function and improve the quality of life of the patients.

Management of optic neuritis

PubMed Central

Menon, Vimla; Saxena, Rohit; Misra, Ruby; Phuljhele, Swati

2011-01-01

Optic neuritis is an inflammatory condition of the optic nerve characterized by a sudden onset of unilateral visual loss, usually affecting young females. Demyelination associated with multiple sclerosis (MS) is the most common cause in regions where MS is prevalent; while in other places, there are a substantial proportion of cases where infective or autoimmune causes are seen. Optic Neuritis Treatment Trial (ONTT) was the first major study that provided information on the natural history, role of steroids in treatment and risk of development of MS. Subsequently, numerous clinical trials have evaluated different modalities of management of optic neuritis and MS. The Controlled High-Risk Subjects Avonex Multiple Sclerosis Prevention Study (CHAMPS); the Prevention of Relapses and Disability by Interferon β-1a Subcutaneously in Multiple Sclerosis (PRISMS) Trial; and, most recently, the Betaferon in Newly Emerging Multiple Sclerosis for Initial Treatment (BENEFIT) Study have provided large amount of information on the natural history of optic neuritis and management options available. However, due to the low prevalence of MS reported in Asian studies, high cost of therapy and indefinite time period of treatment, it may not be cost effective to start interferon therapy in most cases. PMID:21350281

Treatment of traumatic infra orbital nerve paresthesia

PubMed Central

Lone, Parveen Akhter; Singh, R. K.; Pal, U. S.

2012-01-01

This study was done to find out the role of topiramate therapy in infraorbital nerve paresthesia after miniplate fixation in zygomatic complxex fractures. A total 2 cases of unilateral zygomatic complex fracture, 2-3 weeks old with infra orbital nerve paresthesia were slected. Open reduction and plating was done in frontozygomaticregion. Antiepileptic drug tab topiramate was given in therapeutic doses and dose was increased slowly until functional recovery was noticed. PMID:23833503

Space Flight-Associated Neuro-ocular Syndrome.

PubMed

Lee, Andrew G; Mader, Thomas H; Gibson, C Robert; Tarver, William

2017-09-01

New and unique physiologic and pathologic systemic and neuro-ocular responses have been documented in astronauts during and after long-duration space flight. Although the precise cause remains unknown, space flight-associated neuro-ocular syndrome (SANS) has been adopted as an appropriate descriptive term. The Space Medicine Operations Division of the US National Aeronautics and Space Administration (NASA) has documented the variable occurrence of SANS in astronauts returning from long-duration space flight on the International Space Station. These clinical findings have included unilateral and bilateral optic disc edema, globe flattening, choroidal and retinal folds, hyperopic refractive error shifts, and nerve fiber layer infarcts. The clinical findings of SANS have been correlated with structural changes on intraorbital and intracranial magnetic resonance imaging and in-flight and terrestrial ultrasonographic studies and ocular optical coherence tomography. Further study of SANS is ongoing for consideration of future manned missions to space, including a return trip to the moon or Mars.

Gerstmann's syndrome and unilateral optic ataxia in the emergency department

PubMed Central

Barbosa, Breno José Alencar Pires; de Brito, Marcelo Houat; Rodrigues, Júlia Chartouni; Kubota, Gabriel Taricani; Parmera, Jacy Bezerra

2017-01-01

ABSTRACT. A 75-year-old right-handed woman presented to the emergency department with simultanagnosia and right unilateral optic ataxia. Moreover, the patient had agraphia, acalculia, digital agnosia and right-left disorientation, consistent with complete Gerstmann's syndrome. This case highlights the concurrence of Gerstmann's syndrome and unilateral optic ataxia in the acute phase of a left middle cerebral artery stroke. PMID:29354229

Spine Topographical Distribution of Skin α-Synuclein Deposits in Idiopathic Parkinson Disease.

PubMed

Donadio, Vincenzo; Incensi, Alex; Rizzo, Giovanni; Scaglione, Cesa; Capellari, Sabina; Fileccia, Enrico; Avoni, Patrizia; Liguori, Rocco

2017-05-01

Phosphorylated α-synuclein (p-syn) in skin nerves mainly in the proximal sites is a promising neurodegenerative biomarker for idiopathic Parkinson disease (IPD). However, the p-syn spine distribution particularly in patients with unilateral motor dysfunctions remains undefined. This study aimed to investigate in IPD p-syn differences between left and right cervical spine sites in patients with prevalent unilateral motor symptoms, and cervical and thoracic spine sites in patients with bilateral motor symptoms. We enrolled 28 IPD patients fulfilling clinical diagnostic criteria associated with abnormal nigro-striatal DatScan and cardiac MIBG: 15 with prevalently unilateral motor symptoms demonstrated by DatScan; 13 with bilateral motor symptoms and DatScan abnormalities. Patients underwent skin biopsy searching for intraneural p-syn deposits: skin samples were taken from C7 paravertebral left and right sites in unilateral patients and from cervical (C7) and thoracic (Th12) paravertebral spine regions in bilateral patients. Unilateral patients displayed 20% of abnormal p-syn deposits in the affected motor site, 60% in both sites and 20% only in the non-affected site. P-syn was found in all patients in C7 but in only 62% of patients in Th12. Our data showed that cervical p-syn deposits displayed a uniform distribution between both sides not following the motor dysfunction in unilateral patients, and skin nerve p-syn deposits demonstrated a spine gradient with the cervical site expressing the highest positivity. © 2017 American Association of Neuropathologists, Inc. All rights reserved.

Occlusion of carotid artery and hypergravity loading of animals caused similar effects on L-[14C]glutamate uptake in rat brain nerve terminals

NASA Astrophysics Data System (ADS)

Borisova, Tatiana; Sivko, Roman; Krisanova, Natalia

Changes in sodium-dependent L-[14C]glutamate uptake in rat brain nerve terminals was com-paratively analysed after hypergravity loading of animals (centrifugation of rats in special con-tainers at 10 G for 1 hour) and unilateral occlusion of carotid artery (20 min). The initial velocity of L-[14C]glutamate uptake was decreased from 2.5 ± 0.2 nmol x min-1 x mg-1 of proteins to 2.05 ± 0.1 nmol x min-1 x mg-1 of proteins after hypergravity and after occlusion -up to 2.25 ± 0.1 nmol x min-1 x mg-1 of proteins. Recently, we have shown that a decrease in L-[14C]glutamate uptake was at least partially caused by the redaction in the membrane potential of nerve terminals and the proton gradient of synaptic vesicles. These parameters were analysed after unilateral occlusion of carotid artery, where one brain hemisphere was used as a control, whereas the second one as subjected to ischemic/hypoxic conditions. Similarly with hypergravity, we revealed a decrease in the membrane potential of nerve terminals by ˜ 10 % and a reduction of the proton gradient of synaptic vesicles by ˜ 5 % after occlusion of carotid artery. Thus, a decrease in the activity of glutamate transporters after hypergrav-ity and unilateral occlusion of carotid artery was at least partially caused by changes in the membrane potential of nerve terminals and the proton gradient of synaptic vesicles. This fact may be considered in support of the suggestion that ischemia/hypoxia was a main unspecific stressor, which caused the alterations in glutamatergic neurotransmission under conditions of hypergravity.

Hemicrania Continua: Beneficial Effect of Non-Invasive Vagus Nerve Stimulation in a Patient With a Contraindication for Indomethacin.

PubMed

Eren, Ozan; Straube, Andreas; Schöberl, Florian; Schankin, Christoph

2017-02-01

Hemicrania continua (HC) is a primary chronic headache disorder, characterized by a continuous and strictly unilateral headache, with possible cranial autonomic symptoms during episodes of pain exacerbation. The unilateral headache generally responds well to indomethacin; however, continuous indomethacin intake is often not tolerated due to severe adverse effects, like hypertension, gastrointestinal discomfort (especially if combined with aspirin), slightly increased risk of vascular events, and bronchial spasms. Therefore, alternative treatment options are desperately needed. Non-invasive vagus nerve stimulation (nVNS) has been shown to be effective in patients with cluster headache, another trigeminal autonomic cephalalgia (TAC), with cranial parasympathetic autonomic activation during the attacks. © 2016 American Headache Society.

Studies on the cellular localization of spinal cord substance P receptors.

PubMed

Helke, C J; Charlton, C G; Wiley, R G

1986-10-01

Substance P-immunoreactivity and specific substance P binding sites are present in the spinal cord. Receptor autoradiography showed the discrete localization of substance P binding sites in both sensory and motor regions of the spinal cord and functional studies suggested an important role for substance P receptor activation in autonomic outflow, nociception, respiration and somatic motor function. In the current studies, we investigated the cellular localization of substance P binding sites in rat spinal cord using light microscopic autoradiography combined with several lesioning techniques. Unilateral injections of the suicide transport agent, ricin, into the superior cervical ganglion reduced substance P binding and cholinesterase-stained preganglionic sympathetic neurons in the intermediolateral cell column. However, unilateral electrolytic lesions of ventral medullary substance P neurons which project to the intermediolateral cell column did not alter the density of substance P binding in the intermediolateral cell column. Likewise, 6-hydroxydopamine and 5,7-dihydroxytryptamine, which destroy noradrenergic and serotonergic nerve terminals, did not reduce the substance P binding in the intermediolateral cell column. It appears, therefore, that the substance P binding sites are located postsynaptically on preganglionic sympathetic neurons rather than presynaptically on substance P-immunoreactive processes (i.e. as autoreceptors) or on monoamine nerve terminals. Unilateral injections of ricin into the phrenic nerve resulted in the unilateral destruction of phrenic motor neurons in the cervical spinal cord and caused a marked reduction in the substance P binding in the nucleus. Likewise, sciatic nerve injections of ricin caused a loss of associated motor neurons in the lateral portion of the ventral horn of the lumbar spinal cord and a reduction in the substance P binding. Sciatic nerve injections of ricin also destroyed afferent nerves of the associated dorsal root ganglia and increased the density of substance P binding in the dorsal horn. Capsaicin, which destroys small diameter primary sensory neurons, similarly increased the substance P binding in the dorsal horn. These studies show that the cellular localization of substance P binding sites can be determined by analysis of changes in substance P binding to discrete regions of spinal cord after selective lesions of specific groups of neurons. The data show the presence of substance P binding sites on preganglionic sympathetic neurons in the intermediolateral cell column and on somatic motor neurons in the ventral horn, including the phrenic motor nucleus.(ABSTRACT TRUNCATED AT 400 WORDS)

Phrenic nerve decompression for the management of unilateral diaphragmatic paralysis – preoperative evaluation and operative technique

PubMed Central

Hoshide, Reid; Brown, Justin

2017-01-01

Background: Unilateral diaphragmatic paralysis (UDP) can be a very disabling, typically causing shortness of breath and reduced exercise tolerance. We present a case of a surgical decompression of the phrenic nerve of a patient who presented with UDP, which occurred following cervical spine surgery. Methods: The workup for the etiology of UDP demonstrated paradoxical movement on “sniff test” and notably impaired pulmonary function tests. Seven months following the onset of the UDP, he underwent a surgical decompression of the phrenic nerve at the level of the anterior scalene. Results: He noted rapid symptomatic improvement following surgery and reversal of the above noted objective findings was documented. At his 4-year follow-up, he had complete resolution of his clinical symptoms. Repeated physiologic testing of his respiratory function had shown a complete reversal of his UDP. Conclusions: Anatomical compression of the phrenic nerve by redundant neck vasculature should be considered in the differential diagnosis of UDP. Here we demonstrated the techniques in workup and surgical management, with both subjective and objective evidence of success. PMID:29184705

Phrenic nerve decompression for the management of unilateral diaphragmatic paralysis - preoperative evaluation and operative technique.

PubMed

Hoshide, Reid; Brown, Justin

2017-01-01

Unilateral diaphragmatic paralysis (UDP) can be a very disabling, typically causing shortness of breath and reduced exercise tolerance. We present a case of a surgical decompression of the phrenic nerve of a patient who presented with UDP, which occurred following cervical spine surgery. The workup for the etiology of UDP demonstrated paradoxical movement on "sniff test" and notably impaired pulmonary function tests. Seven months following the onset of the UDP, he underwent a surgical decompression of the phrenic nerve at the level of the anterior scalene. He noted rapid symptomatic improvement following surgery and reversal of the above noted objective findings was documented. At his 4-year follow-up, he had complete resolution of his clinical symptoms. Repeated physiologic testing of his respiratory function had shown a complete reversal of his UDP. Anatomical compression of the phrenic nerve by redundant neck vasculature should be considered in the differential diagnosis of UDP. Here we demonstrated the techniques in workup and surgical management, with both subjective and objective evidence of success.

Demyelination of vestibular nerve axons in unilateral Ménière's disease.

PubMed

Spencer, Robert F; Sismanis, Aristides; Kilpatrick, Jefferson K; Shaia, Wayne T

2002-11-01

We conducted a study to determine whether vestibular nerves in patients with unilateral Ménière's disease whose symptoms are refractory to medical management exhibit neuropathologic changes. We also endeavored to determine whether retrocochlear abnormalities are primary or secondary factors in the disease process. To these ends, we obtained vestibular nerve segments from five patients during retrosigmoid (posterior fossa) neurectomy, immediately fixed them, and processed them for light and electron microscopy. We found that all five segments exhibited moderate to severe demyelination with axonal sparing. Moreover, we noted that reactive astrocytes produced an extensive proliferation of fibrous processes and that the microglia assumed a phagocytic role. We conclude that the possible etiologies of demyelination include viral and/or immune-mediated factors similar to those seen in other demyelinating diseases, such as multiple sclerosis and Guillain-Barré syndrome. Our findings suggest that some forms of Ménière's disease that are refractory to traditional medical management might be the result of retrocochlear pathology that affects the neuroglial portion of the vestibular nerve.

Age-related ultrastructural and monoamine oxidase changes in the rat optic nerve.

PubMed

Taurone, S; Ripandelli, G; Minni, A; Lattanzi, R; Miglietta, S; Pepe, N; Fumagalli, L; Micera, A; Pastore, F S; Artico, M

2016-01-01

The aim of this paper is to study the morphology and the distribution of the monoamine oxidase enzymatic system in the optic nerve of 4 month-old Wistar (young) and 28 month-old Wistar (old) rats. The optic nerve was harvested from 20 young and old rats. The segment of optic nerve was divided longitudinally into two pieces, each 0.1 mm in length. The first piece was used for transmission electron microscopy. The second piece was stained with histochemical reaction for monoamine oxidase. The agerelated changes in the optic nerve of rats include micro-anatomical details, ultrastructure and monoamine oxidase histochemical staining. A strong decrease of the thin nerve fibers and a swelling of the thick ones can be observed in optic nerve fibers of old rats. Increased monoamine oxidase histochemical staining of the optic nerve of aged rats is well demonstrated. The increase of meningeal shealth and the decrease of thin nerve fibers of the optic nerve in old rats are well documented. Morphological, ultrastructural and histochemical changes observed in optic nerve fibers of the old rats show a close relation with aging.

Early extraction: a silver bullet to avoid nerve injury in lower third molar removal?

PubMed

Zhang, Q-B; Zhang, Z-Q

2012-10-01

This retrospective study evaluated the effects of early extraction of immature lower third molar on preventing complications, particularly nerve injury following lower third molar removal. Patients were grouped according to age and radiographic results: group A (518 patients, ≤23 years, immature teeth with apical foramen not closed); group B (532 patients, >23 years, mature teeth with closed apical foramen). Group A included 230 males and 288 females (average age 17 years). In group A, 808 lower mandibular third molars were extracted bilaterally in 290 and unilaterally in 228 patients; the incidence of complications was 2.48% (20/808) (all were temporary), the incidence of nerve injury was 0%. Group B included 250 males and 282 females (average age 39 years). In group B, 810 lower third molars were extracted bilaterally in 278 and unilaterally in 254 patients; the incidence of complications was 10% (81/810), the incidence of nerve injury was 1.6% (13/810). All complications were temporary, except two removals of permanent inferior alveolar nerve numbness (>6 months). In this study, early removal of the lower third molar was effective in avoiding some postoperative complications, especially nerve injury. Early extraction of lower third molar in youngsters is recommended following a team consultation. Copyright © 2012 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

[Facial nerve injuries cause changes in central nervous system microglial cells].

PubMed

Cerón, Jeimmy; Troncoso, Julieta

2016-12-01

Our research group has described both morphological and electrophysiological changes in motor cortex pyramidal neurons associated with contralateral facial nerve injury in rats. However, little is known about those neural changes, which occur together with changes in surrounding glial cells. To characterize the effect of the unilateral facial nerve injury on microglial proliferation and activation in the primary motor cortex. We performed immunohistochemical experiments in order to detect microglial cells in brain tissue of rats with unilateral facial nerve lesion sacrificed at different times after the injury. We caused two types of lesions: reversible (by crushing, which allows functional recovery), and irreversible (by section, which produces permanent paralysis). We compared the brain tissues of control animals (without surgical intervention) and sham-operated animals with animals with lesions sacrificed at 1, 3, 7, 21 or 35 days after the injury. In primary motor cortex, the microglial cells of irreversibly injured animals showed proliferation and activation between three and seven days post-lesion. The proliferation of microglial cells in reversibly injured animals was significant only three days after the lesion. Facial nerve injury causes changes in microglial cells in the primary motor cortex. These modifications could be involved in the generation of morphological and electrophysiological changes previously described in the pyramidal neurons of primary motor cortex that command facial movements.

Computed tomographic diagnosis of unilateral cavernous sinus syndrome caused by a chondrosarcoma in a dog: a case report.

PubMed

Hernández-Guerra, Angel María; Del Mar López-Murcia, María; Planells, Alicia; Corpa, Juan Manuel; Liste, Fernando

2007-07-01

An eight-year old Rottweiler dog was presented with signs of enophthalmia, ptosis, anisocoria and mydriasis of the right eye, which showed visual disturbance, reduced or absent reflexes, and ophthalmoplegia. Consensual pupillary light reflex was also absent in the left eye. These neurological deficits were compatible with cavernous sinus syndrome. Computed tomography images of the cavernous sinus and the optical fissure revealed a mildly calcified mass arising from the right presphenoid bone extending further caudally into the orbital foramina. This extension of the mass affected the normal function of several cranial nerves. The dog was euthanased within one year of the initial presentation following development of forebrain signs. A chondrosarcoma was diagnosed histologically after necropsy.

Optic Nerve Decompression

MedlinePlus

... Nerve Decompression Dacryocystorhinostomy (DCR) Disclosure Statement Printer Friendly Optic Nerve Decompression John Lee, MD Introduction Optic nerve decompression is a surgical procedure aimed at ...

RGC Neuroprotection Following Optic Nerve Trauma Mediated By Intranasal Delivery of Amnion Cell Secretome

PubMed Central

Grinblat, Gabriela A.; Khan, Reas S.; Dine, Kimberly; Wessel, Howard; Brown, Larry; Shindler, Kenneth S.

2018-01-01

Purpose Intranasally delivered ST266, the biological, proteinaceous secretome of amnion-derived multipotent progenitor cells, reduces retinal ganglion cell (RGC) loss, optic nerve inflammation, and demyelination in experimental optic neuritis. This unique therapy and novel administration route delivers numerous cytokines and growth factors to the eye and optic nerve, suggesting a potential to also treat other optic neuropathies. Thus, ST266-mediated neuroprotection was examined following traumatic optic nerve injury. Methods Optic nerve crush injury was surgically induced in C57BL/6J mice. Mice were treated daily with intranasal PBS or ST266. RGC function was assessed by optokinetic responses (OKRs), RGCs were counted, and optic nerve sections were stained with luxol fast blue and anti-neurofilament antibodies to assess myelin and RGC axon damage. Results Intranasal ST266 administered daily for 5 days, beginning at the time that a 1-second optic nerve crush was performed, significantly attenuated OKR decreases. Furthermore, ST266 treatment reduced damage to RGC axons and myelin within optic nerves, and blocked RGC loss. Following a 4-second optic nerve crush, intranasal ST266 increased RGC survival and showed a trend toward reduced RGC axon and myelin damage. Ten days following optic nerve crush, ST266 prevented myelin damage, while also inducing a trend toward increased RGC survival and visual function. Conclusions ST266 significantly attenuates traumatic optic neuropathy. Neuroprotective effects of this unique combination of biologic molecules observed here and previously in optic neuritis suggest potential broad application for preventing neuronal damage in multiple optic nerve disorders. Furthermore, results support intranasal delivery as a novel, noninvasive therapeutic modality for eyes and optic nerves. PMID:29847652

Complete unilateral ophthalmoplegia in herpes zoster ophthalmicus.

PubMed

Sanjay, Srinivasan; Chan, Errol Wei'en; Gopal, Lekha; Hegde, Smita Rane; Chang, Benjamin Chong-Ming

2009-12-01

Based on a review of 20 well-documented cases reported in the English literature between 1968 and 2008, herpes zoster ophthalmicus (HZO) may rarely be associated with complete unilateral ophthalmoplegia, defined here as impaired ocular ductions in all 4 directions within 3 months of onset of manifestations of HZO. Ophthalmoplegia occurred equally in immune-competent and immune-incompetent individuals. HZO preceded ophthalmoplegia in 75% by a mean interval of 9.5 days and a range of 2 to 60 days, occurred simultaneously with ophthalmoplegia in 20%, and followed by 2 days the onset of ophthalmoplegia in only 5%. Concurrent conjunctival inflammation, keratitis, or anterior uveitis was present in 90%. Lumbar puncture showed features of aseptic meningitis in 88%, slightly more than the 40%-50% found in patients with HZO without ophthalmoplegia. On orbit/brain imaging, abnormal enlargement of the extraocular muscles was present in 33%, and orbital soft tissue swelling was present in 17%. Enhancement of ocular motor cranial nerves was not reported. Complete or near-complete resolution of ophthalmoplegia occurred in 65% within a range of 2 weeks to 1.5 years (mean 4.4 months). A single autopsy report described granulomatous angiitis of the meninges and large vessels in the anterior cerebral circulation, as well as periaxial infarction in the optic nerve, pons, and medulla but without viral inclusion bodies or antigen. Unsettled issues are whether the pathogenesis is direct viral invasion or an immune reaction to the virus, whether the impaired ocular ductions are based on myopathic or neuropathic injury, whether there are predisposing factors to the combination of HZO and complete ophthalmoplegia, and whether treatment is effective.

[Gradient-index (GRIN) endoscopic examinations from the inner structures of the optic nerve meninges].

PubMed

Sens, Frank Michael; Killer, Hanspeter Esriel; Meyer, Peter

2003-03-01

Due to the excellent image quality and the small outer diameter of the GRIN-(gradient index) endoscope tips we were able to examine the subdural and the subarachnoidal space of the optic nerve meninges by endoscopy. This examination was performed to obtain more information about the inner structure of the optic nerve meninges. In this post-mortem study 7 optic nerves were examined from the chiasm to the globe by GRIN endoscopy (Volpi, Schlieren, Switzerland), with an outer diameter of 0.89 mm, integrated optic of 0.5 mm diameter and an integrated fluid channel of 0.2 mm diameter. In all cases the endoscopic examination of the optic nerve meninges was technically easy to perform. It was possible to study the inner surface of the nerve sheaths and the nerve sheath spaces in close-up. We found horizontal and vertical cords on the inner surface of the dura mater, which could tighten by movements of the optic nerve. With a gradient-index (GRIN) endoscope we obtained new information about the inner structure of the optic nerve meninges. New theories about the changes of the optic nerve meninges during movements of the optic nerve may evolve from this study. Further studies with this new method should be encouraged.

[Isolated palsy of the hypoglossal nerve complicating infectious mononucleosis].

PubMed

Carra-Dallière, C; Mernes, R; Juntas-Morales, R

2011-01-01

Neurological complications of infectious mononucleosis are rare. Various disorders have been described: meningitis, encephalitis, peripheral neuropathy. Isolated cranial nerve palsy has rarely been reported. A 16-year-old man was admitted for isolated and unilateral hypoglossal nerve palsy, four weeks after infectious mononucleosis. Cerebral MRI, cerebrospinal fluid study and electromyography were normal. IgM anti-VCA were positive. Two months later, without treatment, the tongue had almost fully recovered. To the best of our knowledge, only seven cases of isolated palsy of the hypoglossal nerve complicating infectious mononucleosis have been previously reported. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

The epidemiologic characteristics and clinical course of ophthalmopathy associated with autoimmune thyroid disease in Olmsted County, Minnesota.

PubMed Central

Bartley, G B

1994-01-01

Among incident cases of GO in Olmsted County, Minnesota: GO affected females six times more frequently than males (86% versus 14% of cases, respectively). The age-adjusted incidence rate was 16 cases per 100,000 population per year for females and 2.9 cases per 100,000 population for males. The peak incidence rates were bimodal, occurring in the age groups 40 to 44 years and 60 to 64 years in females and 45 to 49 years and 65 to 69 years in males. Among patients with GO, approximately 90% had Graves' hyperthyroidism, 1% had primary hypothyroidism, 3% had Hashimoto's thyroiditis, and 5% were euthyroid. Eyelid retraction was the most common ophthalmic feature of autoimmune thyroid disease, being present either unilaterally or bilaterally in more than 90% of patients at some point in their clinical course. Exophthalmos of one or both eyes affected approximately 60% of patients, restrictive extraocular myopathy was apparent in about 40% of patients, and optic nerve dysfunction occurred in either one or both eyes in 6% of patients with autoimmune thyroid disease. Only 5% of patients had the complete constellation of classic findings: eyelid retraction, exophthalmos, optic nerve dysfunction, extraocular muscle involvement, and hyperthyroidism. Upper eyelid retraction, either unilateral or bilateral, was documented in approximately 75% of patients at the time of diagnosis of GO. Lid lag also was a frequent early sign, being present either unilaterally or bilaterally in 50% of patients at the initial examination. At the time of diagnosis of GO, the most frequent ocular symptom was pain or discomfort, which affected 30% of patients. Some degree of diplopia was noted by approximately 17% of patients, lacrimation or photophobia was present in about 15% to 20% of patients, and 7.5% of patients complained of blurred vision. Decreased vision attributable to optic neuropathy was present in less than 2% of eyes at the time of diagnosis of GO. Thyroid dermopathy and acropachy accompanied GO in approximately 4% and 1% of patients, respectively. Myasthenia gravis occurred in less than 1% of patients. Superior limbic keratoconjunctivitis was documented in less than 4% of patients. The median age at the time of diagnosis of GO was 43 years (range, 8 to 88). Among patients with hyperthyroidism, 61% developed ophthalmopathy within 1 year of the onset of thyrotoxicosis. Symptoms and signs for which statistically significant changes occurred between the initial and final examinations included lacrimation, pain or ocular discomfort, photophobia, eyelid retraction, lid lag, eyelid fullness, conjunctival injection, chemosis, and exophthalmos.(ABSTRACT TRUNCATED AT 400 WORDS) Images FIGURE 1 FIGURE 2 FIGURE 3 PMID:7886878

Tic douloureux.

PubMed

Sweeney, P J

1981-02-01

Tic douloureux (trigerminal neuralgia) usually has its onset in the sixth or seventh decade and is characterized by severe, excruciating facial pain which is almost always unilateral. The mandibular division and the maxillary division of the fifth cranial nerve are most commonly affected. Carbamazepine is the drug of choice. Currently popular surgical procedures include decompression of the fifth cranial nerve and percutaneous thermal lesioning of the gasserian ganglion.

Sporadic Schwannomatosis: A Systematic Review Following the 2005 Consensus Statement.

PubMed

Chick, Gregoire; Victor, Jan; Poujade, Thibault; Hollevoet, Nadine

2018-06-14

 To identify the frequency of reports of sporadic schwannomatosis, the types of patients affected, and the nerves affected.  We identified all case reports and case series that reported on patients with sporadic schwannomatosis according to established criteria.  The initial search yielded 1,597 studies, of which 15 were included. A total of 38 of 55 individuals met the inclusion criteria. The mean age of the patients was 48 years; 41% were male. Thirty-three patients had peripheral nerve tumors, and 17 had spinal tumors. Twelve had tumors in both locations. Tumor distribution was unilateral in 25 of 30 cases (83.3%) and segmental (limited to one limb or five or fewer contiguous segments of the spine) in 28 of 38 cases (73.7%).  This systematic review quantified the number of individuals who meet the criteria for sporadic schwannomatosis and better described this population to facilitate the classification of neurofibromatosis in regard to the 2005 consensus statement. Unilateral or segmental distribution of nerve tumors are key aspects when dealing with multiple noncutaneous schwannomas without involvement of the vestibular nerve. Georg Thieme Verlag KG Stuttgart · New York.

Unilateral or "side-locked" migrainous headache with autonomic symptoms linked to night guard use.

PubMed

Strahlendorf, Jean; Schiffer, Randolph; Strahlendorf, Howard

2008-01-01

Night guards are commonly prescribed as a palliative measure for bruxism, temporomandibular joint symptoms, and associated disorders. We describe a patient with a 10- to 12-year history of night guard use with concurrent unilateral side-locked migrainous headaches with autonomic symptoms characteristic of trigeminal autonomic cephalgia. These headaches were refractory to numerous pharmacological interventions. Upon self-initiated cessation of night guard use, there was complete remission of headaches. We believe the headaches were initiated by night guard-initiated irritation of the trigeminal nerve and a trigeminal autonomic reflex resulting in unilateral migrainous headache with autonomic signs.

Restoring penis sensation in patients with low spinal cord lesions: the role of the remaining function of the dorsal nerve in a unilateral or bilateral TOMAX procedure.

PubMed

Overgoor, Max L E; Braakhekke, Jan P; Kon, Moshe; De Jong, Tom P V M

2015-04-01

The recently developed TOMAX-procedure restores unilateral genital sensation, improving sexual health in men with a low spinal lesion (LSL). It connects one dorsal nerve of the penis (DNP) to the intact ipsilateral ilioinguinal nerve. We proposed bilateral neurotization for full sensation of the glans but this entails cutting both DNPs, risking patients' erection/ejaculation ability. The objective was to select patients for a bilateral TOMAX-procedure by measuring remaining DNP function, and perform the first bilateral cases. In 30 LSL patients with no penile- but normal groin sensation selected for a unilateral TOMAX-procedure the integrity of the sacral-reflex-arc and DNP function was tested pre-operatively using bilateral needle electromyography (EMG)-bulbocavernosus reflex (BCR) measurements, and an interview about reflex erections (RE) ability. In 13 spina bifida- and 17 spinal cord injury patients [median age 29.5 years (range 13-59 years), spinal lesion T12 (incomplete) to sacral], seven (23%) patients reported RE, four (57%) with intact BCR, and of nine (30%) patients with intact BCR, four reported RE (44%). Even patients with a LSL and no penile sensation can have signs of remaining DNP function, but cutting both DNPs to restore full glans sensation in a bilateral TOMAX-procedure might interfere with their RE/ejaculation. To avoid this risk, we propose a selecting-protocol for a unilateral- or bilateral procedure using RE and BCR measurements. Using this protocol, three patients were bilaterally operated with promising preliminary results. Full sensation of the glans could lead to further improvement in sexual function. © 2014 Wiley Periodicals, Inc.

Response of vestibular-nerve afferents to active and passive rotations under normal conditions and after unilateral labyrinthectomy.

PubMed

Sadeghi, Soroush G; Minor, Lloyd B; Cullen, Kathleen E

2007-02-01

We investigated the possible contribution of signals carried by vestibular-nerve afferents to long-term processes of vestibular compensation after unilateral labyrinthectomy. Semicircular canal afferents were recorded from the contralesional nerve in three macaque monkeys before [horizontal (HC) = 67, anterior (AC) = 66, posterior (PC) = 50] and 1-12 mo after (HC = 192, AC = 86, PC = 57) lesion. Vestibular responses were evaluated using passive sinusoidal rotations with frequencies of 0.5-15 Hz (20-80 degrees /s) and fast whole-body rotations reaching velocities of 500 degrees /s. Sensitivities to nonvestibular inputs were tested by: 1) comparing responses during active and passive head movements, 2) rotating the body with the head held stationary to activate neck proprioceptors, and 3) encouraging head-restrained animals to attempt to make head movements that resulted in the production of neck torques of < or =2 Nm. Mean resting discharge rate before and after the lesion did not differ for the regular, D (dimorphic)-irregular, or C (calyx)-irregular afferents. In response to passive rotations, afferents showed no change in sensitivity and phase, inhibitory cutoff, and excitatory saturation after unilateral labyrinthectomy. Moreover, head sensitivities were similar during voluntary and passive head rotations and responses were not altered by neck proprioceptive or efference copy signals before or after the lesion. The only significant change was an increase in the proportion of C-irregular units postlesion, accompanied by a decrease in the proportion of regular afferents. Taken together, our findings show that changes in response properties of the vestibular afferent population are not likely to play a major role in the long-term changes associated with compensation after unilateral labyrinthectomy.

Weight bearing of the limb as a confounding factor in assessment of mechanical allodynia in the rat.

PubMed

Kauppila, T; Kontinen, V K; Pertovaara, A

1998-01-01

Effect of weight bearing of the hindlimbs on the assessment of mechanically-induced hindlimb withdrawal threshold was determined in intact rats and in rats with various pathophysiological conditions causing allodynia or hyperalgesia. Hindlimb withdrawal was elicited by applying a series of calibrated monofilaments to the plantar or the dorsal surface of the paw. During testing the rat was either in a restraint tube with hindlimbs hanging semi-extended without weight bearing or it was standing on a metal grid (bearing its own weight). In intact rats, the withdrawal thresholds were significantly lower when the stimulus site was the dorsal hairy skin rather than the plantar glabrous skin. Also, thresholds were significantly lower when the hindlimbs were not bearing weight. Following carrageenan-induced unilateral inflammation of the plantar paw or a tibial nerve cut there was a marked threshold decrease to test stimuli applied to plantar or dorsal paw, respectively, ipsilateral to the pathological condition in standing rats. However, when the hindlimbs were not weight bearing the unilateral threshold decrease was markedly attenuated (carrageenan-treated rats) or completely abolished (tibial cut). In contrast, in rats with a unilateral spinal nerve ligation the threshold decrease ipsilateral to the nerve lesion was highly significant independent of the weight bearing of the hindlimbs. The results indicate that weight bearing of hindlimbs is an important confounding factor in the assessment of tactile allodynia in rats.

Magnetic resonance imaging of optic nerve

PubMed Central

Gala, Foram

2015-01-01

Optic nerves are the second pair of cranial nerves and are unique as they represent an extension of the central nervous system. Apart from clinical and ophthalmoscopic evaluation, imaging, especially magnetic resonance imaging (MRI), plays an important role in the complete evaluation of optic nerve and the entire visual pathway. In this pictorial essay, the authors describe segmental anatomy of the optic nerve and review the imaging findings of various conditions affecting the optic nerves. MRI allows excellent depiction of the intricate anatomy of optic nerves due to its excellent soft tissue contrast without exposure to ionizing radiation, better delineation of the entire visual pathway, and accurate evaluation of associated intracranial pathologies. PMID:26752822

Fungiform taste bud degeneration in C57BL/6J mice following chorda-lingual nerve transection.

PubMed

Guagliardo, Nick A; Hill, David L

2007-09-10

Taste buds are dependent on innervation for normal morphology and function. Fungiform taste bud degeneration after chorda tympani nerve injury has been well documented in rats, hamsters, and gerbils. The current study examines fungiform taste bud distribution and structure in adult C57BL/6J mice from both intact taste systems and after unilateral chorda-lingual nerve transection. Fungiform taste buds were visualized and measured with the aid of cytokeratin 8. In control mice, taste buds were smaller and more abundant on the anterior tip (<1 mm) of the tongue. By 5 days after nerve transection taste buds were smaller and fewer on the side of the tongue ipsilateral to the transection and continued to decrease in both size and number until 15 days posttransection. Degenerating fungiform taste buds were smaller due to a loss of taste bud cells rather than changes in taste bud morphology. While almost all taste buds disappeared in more posterior fungiform papillae by 15 days posttransection, the anterior tip of the tongue retained nearly half of its taste buds compared to intact mice. Surviving taste buds could not be explained by an apparent innervation from the remaining intact nerves. Contralateral effects of nerve transection were also observed; taste buds were larger due to an increase in the number of taste bud cells. These data are the first to characterize adult mouse fungiform taste buds and subsequent degeneration after unilateral nerve transection. They provide the basis for more mechanistic studies in which genetically engineered mice can be used. (c) 2007 Wiley-Liss, Inc.

Facial reanimation with gracilis muscle transfer neurotized to cross-facial nerve graft versus masseteric nerve: a comparative study using the FACIAL CLIMA evaluating system.

PubMed

Hontanilla, Bernardo; Marre, Diego; Cabello, Alvaro

2013-06-01

Longstanding unilateral facial paralysis is best addressed with microneurovascular muscle transplantation. Neurotization can be obtained from the cross-facial or the masseter nerve. The authors present a quantitative comparison of both procedures using the FACIAL CLIMA system. Forty-seven patients with complete unilateral facial paralysis underwent reanimation with a free gracilis transplant neurotized to either a cross-facial nerve graft (group I, n=20) or to the ipsilateral masseteric nerve (group II, n=27). Commissural displacement and commissural contraction velocity were measured using the FACIAL CLIMA system. Postoperative intragroup commissural displacement and commissural contraction velocity means of the reanimated versus the normal side were first compared using the independent samples t test. Mean percentage of recovery of both parameters were compared between the groups using the independent samples t test. Significant differences of mean commissural displacement and commissural contraction velocity between the reanimated side and the normal side were observed in group I (p=0.001 and p=0.014, respectively) but not in group II. Intergroup comparisons showed that both commissural displacement and commissural contraction velocity were higher in group II, with significant differences for commissural displacement (p=0.048). Mean percentage of recovery of both parameters was higher in group II, with significant differences for commissural displacement (p=0.042). Free gracilis muscle transfer neurotized by the masseteric nerve is a reliable technique for reanimation of longstanding facial paralysis. Compared with cross-facial nerve graft neurotization, this technique provides better symmetry and a higher degree of recovery. Therapeutic, III.

Histone deacetylase expression patterns in developing murine optic nerve

PubMed Central

2014-01-01

Background Histone deacetylases (HDACs) play important roles in glial cell development and in disease states within multiple regions of the central nervous system. However, little is known about HDAC expression or function within the optic nerve. As a first step in understanding the role of HDACs in optic nerve, this study examines the spatio-temporal expression patterns of methylated histone 3 (K9), acetylated histone 3 (K18), and HDACs 1–6 and 8–11 in the developing murine optic nerve head. Results Using RT-qPCR, western blot and immunofluorescence, three stages were analyzed: embryonic day 16 (E16), when astrocyte precursors are found in the optic stalk, postnatal day 5 (P5), when immature astrocytes and oligodendrocytes are found throughout the optic nerve, and P30, when optic nerve astrocytes and oligodendrocytes are mature. Acetylated and methylated histone H3 immunoreactivity was co-localized in the nuclei of most SOX2 positive glia within the optic nerve head and adjacent optic nerve at all developmental stages. HDACs 1–11 were expressed in the optic nerve glial cells at all three stages of optic nerve development in the mouse, but showed temporal differences in overall levels and subcellular localization. HDACs 1 and 2 were predominantly nuclear throughout optic nerve development and glial cell maturation. HDACs 3, 5, 6, 8, and 11 were predominantly cytoplasmic, but showed nuclear localization in at least one stage of optic nerve development. HDACs 4, 9 and10 were predominantly cytoplasmic, with little to no nuclear expression at any time during the developmental stages examined. Conclusions Our results showing that HDACs 1, 2, 3, 5, 6, 8, and 11 were each localized to the nuclei of SOX2 positive glia at some stages of optic nerve development and maturation and extend previous reports of HDAC expression in the aging optic nerve. These HDACs are candidates for further research to understand how chromatin remodeling through acetylation, deacetylation and methylation contributes to glial development as well as their injury response. PMID:25011550

Estimating 3D topographic map of optic nerve head from a single fundus image

NASA Astrophysics Data System (ADS)

Wang, Peipei; Sun, Jiuai

2018-04-01

Optic nerve head also called optic disc is the distal portion of optic nerve locating and clinically visible on the retinal surface. It is a 3 dimensional elliptical shaped structure with a central depression called the optic cup. This shape of the ONH and the size of the depression can be varied due to different retinopathy or angiopathy, therefore the estimation of topography of optic nerve head is significant for assisting diagnosis of those retinal related complications. This work describes a computer vision based method, i.e. shape from shading (SFS) to recover and visualize 3D topographic map of optic nerve head from a normal fundus image. The work is expected helpful for assessing those complications associated the deformation of optic nerve head such as glaucoma and diabetes. The illumination is modelled as uniform over the area around optic nerve head and its direction estimated from the available image. The Tsai discrete method has been employed to recover the 3D topographic map of the optic nerve head. The initial experimental result demonstrates our approach works on most of fundus images and provides a cheap, but good alternation for rendering and visualizing the topographic information of the optic nerve head for potential clinical use.

Neurological abnormalities associated with CDMA exposure.

PubMed

Hocking, B; Westerman, R

2001-09-01

Dysaesthesiae of the scalp and neurological abnormality after mobile phone use have been reported previously, but the roles of the phone per se or the radiations in causing these findings have been questioned. We report finding a neurological abnormality in a patient after accidental exposure of the left side of the face to mobile phone radiation [code division multiple access (CDMA)] from a down-powered mobile phone base station antenna. He had headaches, unilateral left blurred vision and pupil constriction, unilateral altered sensation on the forehead, and abnormalities of current perception thresholds on testing the left trigeminal ophthalmic nerve. His nerve function recovered during 6 months follow-up. His exposure was 0.015-0.06 mW/cm(2) over 1-2 h. The implications regarding health effects of radiofrequency radiation are discussed.

Farris-Tang retractor in optic nerve sheath decompression surgery.

PubMed

Spiegel, Jennifer A; Sokol, Jason A; Whittaker, Thomas J; Bernard, Benjamin; Farris, Bradley K

2016-01-01

Our purpose is to introduce the use of the Farris-Tang retractor in optic nerve sheath decompression surgery. The procedure of optic nerve sheath fenestration was reviewed at our tertiary care teaching hospital, including the use of the Farris-Tang retractor. Pseudotumor cerebri is a syndrome of increased intracranial pressure without a clear cause. Surgical treatment can be effective in cases in which medical therapy has failed and disc swelling with visual field loss progresses. Optic nerve sheath decompression surgery (ONDS) involves cutting slits or windows in the optic nerve sheath to allow cerebrospinal fluid to escape, reducing the pressure around the optic nerve. We introduce the Farris-Tang retractor, a retractor that allows for excellent visualization of the optic nerve sheath during this surgery, facilitating the fenestration of the sheath and visualization of the subsequent cerebrospinal fluid egress. Utilizing a medial conjunctival approach, the Farris-Tang retractor allows for easy retraction of the medial orbital tissue and reduces the incidence of orbital fat protrusion through Tenon's capsule. The Farris-Tang retractor allows safe, easy, and effective access to the optic nerve with good visualization in optic nerve sheath decompression surgery. This, in turn, allows for greater surgical efficiency and positive patient outcomes.

Optic Nerve Disorders

MedlinePlus

The optic nerve is a bundle of more than 1 million nerve fibers that carry visual messages. You have one connecting ... retina) to your brain. Damage to an optic nerve can cause vision loss. The type of vision ...

Retinoblastoma: A Three-Year-Study at a Brazilian Medical School Hospital

PubMed Central

Bonanomi, Maria Teresa Brizzi Chizzotti; de Almeida, Maria Tereza Assis; Cristofani, Lilian Maria; Filho, Vicente Odone

2009-01-01

OBJECTIVE: To present the characteristics and treatment outcomes of patients with retinoblastoma. METHODS: A retrospective case series was conducted to review the records of all new patients diagnosed with retinoblastoma between 2003 and 2005. Eyes with early disease, or advanced disease with potential vision were treated with chemotherapy (carboplatin and etoposide) in conjunction with early local therapy (laser or cryo). Radiotherapy was used in cases where the disease did not respond to the above protocols or in recurrent cases. Eyes in the late stage of disease with no potential vision in the initial examination or eyes and where conservative treatment had failed were enucleated. RESULTS: In total, we reviewed 28 new cases of retinoblastoma, 15 of which were unilateral and 13 of which were bilateral (46%). These data correspond to a mean of 9.3 new cases per year (0.77 case/month). The mean age at diagnosis was 33.8 months for unilateral cases, and 19.15 months for bilateral cases (p=0.015). Leucocoria was the major presenting symptom (75%). All but one patient with unilateral disease had the affected eye enucleated due to advanced disease (mean follow-up: 39.91 months). Among the 13 bilateral cases, 13 eyes (50%) were enucleated, 11 eyes (42.4%) were saved with chemotherapy in conjunction with local therapy and 2 eyes (7.6%) were saved using external beam radiotherapy (mean follow-up: 41.91 months). In unilateral and bilateral disease, pathology data revealed choroid involvement in 50% and 30%, respectively, and optic nerve invasion in 92% and 50%, respectively. CONCLUSION: In this population, retinoblastoma was diagnosed too late and most eyes were consequently enucleated. In cases with bilateral disease, half of the eyes were preserved. PMID:19488609

Herpes zoster ophthalmicus and strabismus: a unique cause of secondary Brown syndrome.

PubMed

Broderick, Kevin M; Raymond, William R; Boden, John H

2017-08-01

Herpes zoster ophthalmicus can be associated with a variety of ocular and visual sequelae, including isolated or even multiple cranial neuropathies, potentially affecting the oculomotor, trochlear, or abducens nerves. We report a case of a secondary Brown syndrome following resolution of a unilateral isolated trochlear nerve palsy associated with herpes zoster ophthalmicus in an immunocompetent 57-year-old man. Published by Elsevier Inc.

Synthesis of elastic microfibrillar components fibrillin-1 and fibrillin-2 by human optic nerve head astrocytes in situ and in vitro.

PubMed

Pena, J D; Mello, P A; Hernandez, M R

2000-05-01

The purpose of this study was to identify elastic microfibrillar components fibrillin-1 and fibrillin-2 in optic nerve heads of adult normal and glaucomatous subjects, in cultured optic nerve head astrocytes (type 1B astrocytes), as well as fibrillin-1 in fetal optic nerve heads. To characterize synthesis and gene expression of microfibrillar proteins in human optic nerve heads and cultured type 1B astrocytes, light microscopy immunohistochemistry, in situ hybridization, and RT-PCR or Northern blots were performed. Our results demonstrated that fibrillin-1 was associated with blood vessels, astrocytes in the glial columns and cribriform plates, and with astrocyte processes in the nerve bundles in all samples. In glaucomatous optic nerves there was enhanced fibrillin-1 immunoreactivity, especially surrounding blood vessels. Fibrillin-2 was localized primarily to blood vessels in all samples, without qualitative differences between normal and glaucomatous samples. In fetal optic nerve heads fibrillin-1 mRNA was localized to glial cells and to the blood vessel walls. In adult optic nerve heads, there was little fibrillin-1 mRNA as detectable by in situ hybridization and RT-PCR. There was no detectable upregulation of fibrillin-1 mRNA in glaucoma. In cultured type 1B astrocytes, fibrillin-1 staining was mostly pericellular. There was little fibrillin-2 immunoreactivity. In conclusion, astrocytes from the optic nerve head deposit elastic microfibrillar components in situ and in vitro, with a predominance of fibrillin-1. Upregulation of fibrillin-1 mRNA was not observed in glaucoma, suggesting that increased transcription may occur early in the disease process. Cultures of type 1B astrocytes from the optic nerve head provides a useful model to study mechanisms regulating the interactions of elastin and the microfibrils in optic nerve head astrocytes.

A novel technique to identify the nerve of origin in head and neck schwannomas.

PubMed

Ching, H H; Spinner, A G; Reeve, N H; Wang, R C

2018-04-18

Identifying the nerve of origin in head and neck schwannomas is a diagnostic challenge. Surgical management leads to a risk of permanent deficit. Accurate identification of the nerve would improve operative planning and patient counselling. Three patients with head and neck schwannomas underwent a diagnostic procedure hypothesised to identify the nerve of origin. The masses were infiltrated with 1 per cent lidocaine solution, and the patients were observed for neurological deficits. All three patients experienced temporary loss of nerve function after lidocaine injection. Facial nerve palsy, voice changes with documented unilateral same-side vocal fold paralysis, and numbness in the distribution of the maxillary nerve (V2), respectively, led to a likely identification of the nerve of origin. Injection of lidocaine into a schwannoma is a safe, in-office procedure that produces a temporary nerve deficit, which may enable accurate identification of the nerve of origin of a schwannoma. Identifying the nerve of origin enhances operative planning and patient counselling.

Recurrent Isolated Oculomotor Nerve Palsy after Radiation of a Mesencephalic Metastasis. Case Report and Mini Review

PubMed Central

Grabau, Olga; Leonhardi, Jochen; Reimers, Carl D.

2014-01-01

Introduction: Recurrent oculomotor nerve palsies are extremely rare clinical conditions. Case report: Here, we report on a unique case of a short-lasting recurrent unilateral incomplete external and complete internal oculomotor nerve palsy. The episodic palsies were probably caused by an ipsilateral mesencephalic metastasis of a breast carcinoma and occurred after successful brain radiation therapy. Discussion: While the pathogenic mechanism remains unclear, the recurrent sudden onset and disappearance of the palsies and their decreasing frequency after antiepileptic treatment suggest the occurrence of epilepsy-like brainstem seizures. A review of case reports of spontaneous reversible oculomotor nerve palsies is presented. PMID:25104947

Unilateral proptosis revealing a fronto-ethmoidal mucocele.

PubMed

Lajmi, Houda; Hmaied, Wassim; Ben Jalel, Wady; Ben Romdhane, Khaoula; Chelly, Zied; El Fekih, Lamia

2017-06-01

Backgroud: The fronto-ethmoidal mucocele is a benign condition leading commonly to limited eye movement or ocular pain but it could also induce visual acuity impairment by compressing the optic nerve Aim: To discuss, through a case report, different ophthalmologic manifestations of the fronto-ethmoidalmucocele. Reported case: A 46-years-old man with no general history consulted for a bilateral ocular redness and itching. He reported, however, a mild protrusion of his left globe evolving for oneyear. The clinical examination revealed a unilateral proptosis in the left eye with a discrete limitation of theadduction. A brain and orbital computer tomography (CT)and a magnetic resonance imaging(MRI)revealed a grade I exophthalmos caused by an oval formation of fluid density in the left anterior and posterior ethmoidal cells in addition to the frontal sinus,driving theeyeball and internal oculomotor muscles back and out.The patient was referred to otorhinolaryngology department for a precocious surgical management. The ophtalmologic manifestations of the disease depend on the location, the size of the formation and involvement of adjacent structures. The loss of vision and the apex syndrome due to the compressionof the ocular globe are the most serious complications.

Ramsay Hunt syndrome with unilateral polyneuropathy involving cranial nerves V, VII, VIII, and XII in a diabetic patient.

PubMed

Sun, Wei-Lian; Yan, Jian-Liang; Chen, Li-Li

2011-01-01

Ramsay Hunt syndrome is a rare complication of the varicella zoster virus, defined as a peripheral facial palsy that typically results from involvement of the facial and auditory nerves. Ramsay Hunt syndrome can be associated with cranial nerves V, VI, IX, and X but rarely with XII. We describe an atypical case of Ramsay Hunt syndrome with multiple cranial nerve involvement of nerves V, VII, VIII, and XII. Antiviral drugs, antibiotics, insulin, and traditional Chinese drugs were administered immediately after admission. After 3 months of combination therapy, the patient had recovered satisfactorily. Herpes zoster can cause severe infections in diabetic patients and should be treated as soon after detection as possible. Ramsay Hunt syndrome should be recognized as a polycranial neuritis characterized by damage to sensory and motor nerves. In addition to facial and vestibular nerve paralysis, Ramsay Hunt syndrome may also involve cranial nerves V and XII.

Longitudinal evidence for anterograde trans-synaptic degeneration after optic neuritis

PubMed Central

Goodkin, Olivia; Altmann, Daniel R.; Jenkins, Thomas M.; Miszkiel, Katherine; Mirigliani, Alessia; Fini, Camilla; Gandini Wheeler-Kingshott, Claudia A. M.; Thompson, Alan J.; Ciccarelli, Olga; Toosy, Ahmed T.

2016-01-01

Abstract In multiple sclerosis, microstructural damage of normal-appearing brain tissue is an important feature of its pathology. Understanding these mechanisms is vital to help develop neuroprotective strategies. The visual pathway is a key model to study mechanisms of damage and recovery in demyelination. Anterograde trans-synaptic degeneration across the lateral geniculate nuclei has been suggested as a mechanism of tissue damage to explain optic radiation abnormalities seen in association with demyelinating disease and optic neuritis, although evidence for this has relied solely on cross-sectional studies. We therefore aimed to assess: (i) longitudinal changes in the diffusion properties of optic radiations after optic neuritis suggesting trans-synaptic degeneration; (ii) the predictive value of early optic nerve magnetic resonance imaging measures for late optic radiations changes; and (iii) the impact on visual outcome of both optic nerve and brain post-optic neuritis changes. Twenty-eight consecutive patients with acute optic neuritis and eight healthy controls were assessed visually (logMAR, colour vision, and Sloan 1.25%, 5%, 25%) and by magnetic resonance imaging, at baseline, 3, 6, and 12 months. Magnetic resonance imaging sequences performed (and metrics obtained) were: (i) optic nerve fluid-attenuated inversion-recovery (optic nerve cross-sectional area); (ii) optic nerve proton density fast spin-echo (optic nerve proton density-lesion length); (iii) optic nerve post-gadolinium T 1 -weighted (Gd-enhanced lesion length); and (iv) brain diffusion-weighted imaging (to derive optic radiation fractional anisotropy, radial diffusivity, and axial diffusivity). Mixed-effects and multivariate regression models were performed, adjusting for age, gender, and optic radiation lesion load. These identified changes over time and associations between early optic nerve measures and 1-year global optic radiation/clinical measures. The fractional anisotropy in patients’ optic radiations decreased ( P = 0.018) and radial diffusivity increased ( P = 0.002) over 1 year following optic neuritis, whereas optic radiation measures were unchanged in controls. Also, smaller cross-sectional areas of affected optic nerves at 3 months post-optic neuritis predicted lower fractional anisotropy and higher radial diffusivity at 1 year ( P = 0.007) in the optic radiations, whereas none of the inflammatory measures of the optic nerve predicted changes in optic radiations. Finally, greater Gd-enhanced lesion length at baseline and greater optic nerve proton density-lesion length at 1 year were associated with worse visual function at 1 year ( P = 0.034 for both). Neither the cross-sectional area of the affected optic nerve after optic neuritis nor the damage in optic radiations was associated with 1-year visual outcome. Our longitudinal study shows that, after optic neuritis, there is progressive damage to the optic radiations, greater in patients with early residual optic nerve atrophy, even after adjusting for optic radiation lesions. These findings provide evidence for trans-synaptic degeneration. PMID:26912640

[Pay attention on optical coherence tomography evaluation for optic nerve diseases].

PubMed

Wang, M

2016-12-11

Optical coherence tomography(OCT) had become the most important imaging technique in ophthalmology. OCT is able to segment the retinal nerve fiber layer and retinal ganglion cell layer accurately. Quantitative analysis can be performed for both layers. OCT is very important to evaluate the neuron and axon loss in optic nerve diseases diagnosis. Meanwhile, OCT has great value for differentiating glaucoma and macular diseases from optic nerve diseases. This review presented OCT application in optic nerve diseases diagnosis, differentiation diagnosis, the key points in use and the features of en face OCT and OCT angiography. It gave us suggestions that it should be pay more attention to OCT examination in diagnosis and treatment of optic nerve diseases. (Chin J Ophthalmol, 2016, 52: 885 - 888) .

Cerebral venous hypertension and blindness: a reversible complication.

PubMed

Cuadra, Salvador A; Padberg, Frank T; Turbin, Roger E; Farkas, Jeffrey; Frohman, Larry P

2005-10-01

A 57-year-old woman developed blindness during treatment for sarcoidosis-induced end-stage renal disease. An initial renal transplantation failed, and hemoaccess was maintained with multiple central catheters and upper extremity prosthetic arteriovenous grafts. A successful second transplantation eliminated her need for hemodialysis, but a right brachial to internal jugular graft remained patent. Progressive visual loss 2 years after transplantation prompted ophthalmic evaluation which initially revealed unilateral left optic nerve edema and visual loss, ultimately worsening over several months to no light perception in the left eye, 20/60 vision in the right eye, and bilateral papilledema. Arteriography demonstrated cerebral venous hypertension attributed to the functioning hemoaccess graft. Permanent graft occlusion normalized the papilledema, and visual field defects in the right eye and visual acuity returned to 20/20 in the right eye.

[Glaucoma and optic nerve drusen: Limitations of optic nerve head OCT].

PubMed

Poli, M; Colange, J; Goutagny, B; Sellem, E

2017-09-01

Optic nerve head drusen are congenital calcium deposits located in the prelaminar section of the optic nerve head. Their association with visual field defects has been classically described, but the diagnosis of glaucoma is not easy in these cases of altered optic nerve head anatomy. We describe the case of a 67-year-old man with optic nerve head drusen complicated by glaucoma, which was confirmed by visual field and OCT examination of the peripapillary retinal nerve fiber layer (RNFL), but the measurement of the minimum distance between the Bruch membrane opening and the internal limiting membrane (minimum rim width, BMO-MRW) by OCT was normal. OCT of the BMO-MRW is a new diagnostic tool for glaucoma. Superficial optic nerve head drusen, which are found between the internal limiting membrane and the Bruch's membrane opening, overestimate the value of this parameter. BMO-MRW measurement is not adapted to cases of optic nerve head drusen and can cause false-negative results for this parameter, and the diagnosis of glaucoma in this case should be based on other parameters such as the presence of a fascicular defect in the retinal nerve fibers, RNFL or macular ganglion cell complex thinning, as well as visual field data. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

High Spatial Resolution Imaging Mass Spectrometry of Human Optic Nerve Lipids and Proteins

NASA Astrophysics Data System (ADS)

Anderson, David M. G.; Spraggins, Jeffrey M.; Rose, Kristie L.; Schey, Kevin L.

2015-06-01

The human optic nerve carries signals from the retina to the visual cortex of the brain. Each optic nerve is comprised of approximately one million nerve fibers that are organized into bundles of 800-1200 fibers surrounded by connective tissue and supportive glial cells. Damage to the optic nerve contributes to a number of blinding diseases including: glaucoma, neuromyelitis optica, optic neuritis, and neurofibromatosis; however, the molecular mechanisms of optic nerve damage and death are incompletely understood. Herein we present high spatial resolution MALDI imaging mass spectrometry (IMS) analysis of lipids and proteins to define the molecular anatomy of the human optic nerve. The localization of a number of lipids was observed in discrete anatomical regions corresponding to myelinated and unmyelinated nerve regions as well as to supporting connective tissue, glial cells, and blood vessels. A protein fragment from vimentin, a known intermediate filament marker for astrocytes, was observed surrounding nerved fiber bundles in the lamina cribrosa region. S100B was also found in supporting glial cell regions in the prelaminar region, and the hemoglobin alpha subunit was observed in blood vessel areas. The molecular anatomy of the optic nerve defined by MALDI IMS provides a firm foundation to study biochemical changes in blinding human diseases.

Continuous-wave infrared optical nerve stimulation for potential diagnostic applications

NASA Astrophysics Data System (ADS)

Tozburun, Serhat; Cilip, Christopher M.; Lagoda, Gwen A.; Burnett, Arthur L.; Fried, Nathaniel M.

2010-09-01

Optical nerve stimulation using infrared laser radiation has recently been developed as a potential alternative to electrical nerve stimulation. However, recent studies have focused primarily on pulsed delivery of the laser radiation and at relatively low pulse rates. The objective of this study is to demonstrate faster optical stimulation of the prostate cavernous nerves using continuous-wave (cw) infrared laser radiation for potential diagnostic applications. A thulium fiber laser (λ=1870 nm) is used for noncontact optical stimulation of the rat prostate cavernous nerves in vivo. Optical nerve stimulation, as measured by an intracavernous pressure (ICP) response in the penis, is achieved with the laser operating in either cw mode, or with a 5-ms pulse duration at 10, 20, 30, 40, 50, and 100 Hz. Successful optical stimulation is observed to be primarily dependent on a threshold nerve temperature (42 to 45 °C), rather than an incident fluence, as previously reported. cw optical nerve stimulation provides a significantly faster ICP response time using a lower power (and also less expensive) laser than pulsed stimulation. cw optical nerve stimulation may therefore represent an alternative mode of stimulation for intraoperative diagnostic applications where a rapid response is critical, such as identification of the cavernous nerves during prostate cancer surgery.

Continuous-wave vs. pulsed infrared laser stimulation of the rat prostate cavernous nerves

NASA Astrophysics Data System (ADS)

Tozburun, Serhat; Cilip, Christopher M.; Lagoda, Gwen A.; Burnett, Arthur L.; Fried, Nathaniel M.

2011-03-01

Optical nerve stimulation has recently been developed as an alternative to electrical nerve stimulation. However, recent studies have focused primarily on pulsed delivery of the laser radiation and at relatively low pulse rates. The objective of this study is to demonstrate faster optical stimulation of the prostate cavernous nerves using continuouswave (CW) infrared laser radiation, for potential diagnostic applications. A Thulium fiber laser (λ = 1870 nm) was used for non-contact optical stimulation of the rat prostate cavernous nerves, in vivo. Optical nerve stimulation, as measured by an intracavernous pressure (ICP) response in the penis, was achieved with the laser operating in either CW mode, or with a 5-ms pulse duration at 10, 20, 30, 40, 50, and 100 Hz. Successful optical stimulation was observed to be primarily dependent on a threshold nerve temperature (42-45 °C), not an incident fluence, as previously reported. CW optical nerve stimulation provides a significantly faster ICP response time using a laser with lower power output than pulsed stimulation. CW optical nerve stimulation may therefore represent an alternative mode of stimulation for intra-operative diagnostic applications where a rapid response is critical, such as identification of the cavernous nerves during prostate cancer surgery.

Bell’s palsy: data from a study of 70 cases

PubMed Central

Cirpaciu, D; Goanta, CM

2014-01-01

Bell’s palsy is a condition that affects the facial nerve, which is one of the twelve cranial nerves. Its main function is to control all the muscles of the facial expression. It is a unilateral, acute, partial or complete paralysis of the facial nerve. Bell's palsy remains the most common cause of facial nerve paralysis, more often encountered in females aged 17 to 30 years, recurrent in many cases and with poor associations with other pathologic conditions. In modern literature, the suspected etiology could be due to the reactivation of the latent herpes viral infections in the geniculate ganglia, and their subsequent migration to the facial nerve but, favorable outcome by using vasodilators, neurotrophic and corticosteroid therapy was recorded. PMID:25870668

Bell's palsy: data from a study of 70 cases.

PubMed

Cirpaciu, D; Goanta, C M

2014-01-01

Bell's palsy is a condition that affects the facial nerve, which is one of the twelve cranial nerves. Its main function is to control all the muscles of the facial expression. It is a unilateral, acute, partial or complete paralysis of the facial nerve. Bell's palsy remains the most common cause of facial nerve paralysis, more often encountered in females aged 17 to 30 years, recurrent in many cases and with poor associations with other pathologic conditions. In modern literature, the suspected etiology could be due to the reactivation of the latent herpes viral infections in the geniculate ganglia, and their subsequent migration to the facial nerve but, favorable outcome by using vasodilators, neurotrophic and corticosteroid therapy was recorded.

Differences in individual susceptibility affect the development of trigeminal neuralgia☆

PubMed Central

Duransoy, Yusuf Kurtuluş; Mete, Mesut; Akçay, Emrah; Selçuki, Mehmet

2013-01-01

Trigeminal neuralgia is a syndrome due to dysfunctional hyperactivity of the trigeminal nerve, and is characterized by a sudden, usually unilateral, recurrent lancinating pain arising from one or more divisions of the nerve. The most accepted pathogenetic mechanism for trigeminal neuralgia is compression of the nerve at its dorsal root entry zone or in its distal course. In this paper, we report four cases with trigeminal neuralgia due to an unknown mechanism after an intracranial intervention. The onset of trigeminal neuralgia after surgical interventions that are unrelated to the trigeminal nerve suggests that in patients with greater individual susceptibility, nerve contact with the vascular structure due to postoperative pressure and changes in cerebrospinal fluid flow may cause the onset of pain. PMID:25206428

An Optic Nerve Crush Injury Murine Model to Study Retinal Ganglion Cell Survival

PubMed Central

Tang, Zhongshu; Zhang, Shuihua; Lee, Chunsik; Kumar, Anil; Arjunan, Pachiappan; Li, Yang; Zhang, Fan; Li, Xuri

2011-01-01

Injury to the optic nerve can lead to axonal degeneration, followed by a gradual death of retinal ganglion cells (RGCs), which results in irreversible vision loss. Examples of such diseases in human include traumatic optic neuropathy and optic nerve degeneration in glaucoma. It is characterized by typical changes in the optic nerve head, progressive optic nerve degeneration, and loss of retinal ganglion cells, if uncontrolled, leading to vision loss and blindness. The optic nerve crush (ONC) injury mouse model is an important experimental disease model for traumatic optic neuropathy, glaucoma, etc. In this model, the crush injury to the optic nerve leads to gradual retinal ganglion cells apoptosis. This disease model can be used to study the general processes and mechanisms of neuronal death and survival, which is essential for the development of therapeutic measures. In addition, pharmacological and molecular approaches can be used in this model to identify and test potential therapeutic reagents to treat different types of optic neuropathy. Here, we provide a step by step demonstration of (I) Baseline retrograde labeling of retinal ganglion cells (RGCs) at day 1, (II) Optic nerve crush injury at day 4, (III) Harvest the retinae and analyze RGC survival at day 11, and (IV) Representative result. PMID:21540827

Effect of diabetic retinopathy and panretinal photocoagulation on retinal nerve fiber layer and optic nerve appearance.

PubMed

Lim, Michele C; Tanimoto, Suzana A; Furlani, Bruno A; Lum, Brent; Pinto, Luciano M; Eliason, David; Prata, Tiago S; Brandt, James D; Morse, Lawrence S; Park, Susanna S; Melo, Luiz A S

2009-07-01

To determine if panretinal photocoagulation (PRP) alters retinal nerve fiber layer (RNFL) thickness and optic nerve appearance. Patients with diabetes who did and did not undergo PRP and nondiabetic control subjects were enrolled in a prospective study. Participants underwent optical coherence tomography of the peripapillary retina and optic nerve. Stereoscopic optic nerve photographs were graded in a masked fashion. Ninety-four eyes of 48 healthy individuals, 89 eyes of 55 diabetic patients who did not undergo PRP, and 37 eyes of 24 subjects with diabetes who underwent PRP were included in this study. Eyes that had been treated with PRP had thinner peripapillary RNFL compared with the other groups; this was statistically significantly different in the inferior (P = .004) and nasal (P = .003) regions. Optic nerve cupping did not increase with severity of disease classification, but the proportion of optic nerves graded as suspicious for glaucoma or as having nonglaucomatous optic neuropathy did (P = .008). These grading categories were associated with thinner RNFL measurements. Diabetic eyes that have been treated with PRP have thinner RNFL than nondiabetic eyes. Optic nerves in eyes treated with PRP are more likely to be graded as abnormal, but their appearance is not necessarily glaucomatous and may be related to thinning of the RNFL.

OPTIC NERVE INFILTRATION BY RETINOBLASTOMA: Predictive Clinical Features and Outcome.

PubMed

Kaliki, Swathi; Tahiliani, Prerana; Mishra, Dilip K; Srinivasan, Visweswaran; Ali, Mohammed Hasnat; Reddy, Vijay Anand P

2016-06-01

To identify the clinical features predictive of any optic nerve infiltration and postlaminar optic nerve infiltration by retinoblastoma on histopathology and to report the outcome (metastasis and death) in these patients. Retrospective study. Of the 403 patients who underwent primary enucleation for retinoblastoma, 196 patients had optic nerve tumor infiltration (Group 1) and 207 patients had no evidence of optic nerve tumor infiltration (Group 2). Group 1 included patients with prelaminar (n = 47; 24%), laminar (n = 74; 38%), and postlaminar tumor infiltration with or without involving optic nerve transection (n = 74; 38%). Comparing Group 1 and Group 2, the patients in Group 1 had prolonged duration of symptoms (>6 months) (16% vs. 8%; P = 0.02) and were associated with no vision at presentation (23% vs. 10%; P = 0.01), higher rates of secondary glaucoma (42% vs. 12%; P < 0.0001), iris neovascularization (39% vs. 23%; P < 0.001), and larger tumors (mean tumor thickness, 12.8 mm vs. 12 mm; P = 0.0001). There was a higher prevalence of metastasis in Group 1 than in Group 2 (4% vs. 0%; P = 0.006). On multivariate analysis, clinical features predictive of any optic nerve tumor infiltration secondary glaucoma (hazard ratio = 5.38; P < 0.001) and those predictive of postlaminar optic nerve tumor infiltration included iris neovascularization (hazard ratio = 2.66; P = 0.001) and secondary glaucoma (hazard ratio = 3.13; P < 0.001). In this study, clinical features predictive of any optic nerve tumor infiltration included secondary glaucoma and those predictive of postlaminar optic nerve tumor infiltration included iris neovascularization and secondary glaucoma. Despite adjuvant treatment in those with postlaminar optic nerve tumor infiltration, metastasis occurred in 8% of patients.

Relationship Between Optic Nerve Appearance and Retinal Nerve Fiber Layer Thickness as Explored with Spectral Domain Optical Coherence Tomography

PubMed Central

Aleman, Tomas S.; Huang, Jiayan; Garrity, Sean T.; Carter, Stuart B.; Aleman, Wendy D.; Ying, Gui-shuang; Tamhankar, Madhura A.

2014-01-01

Purpose To study the relationship between the appearance of the optic nerve and the retinal nerve fiber layer (RNFL) thickness determined by spectral domain optical coherence tomography (OCT). Methods Records from patients with spectral domain-OCT imaging in a neuro-ophthalmology practice were reviewed. Eyes with glaucoma/glaucoma suspicion, macular/optic nerve edema, pseudophakia, and with refractive errors > 6D were excluded. Optic nerve appearance by slit lamp biomicroscopy was related to the RNFL thickness by spectral domain-OCT and to visual field results. Results Ninety-one patients (176 eyes; mean age: 49 ± 15 years) were included. Eighty-three eyes (47%) showed optic nerve pallor; 89 eyes (50.6%) showed RNFL thinning (sectoral or average peripapillary). Average peripapillary RNFL thickness in eyes with pallor (mean ± SD = 76 ± 17 μm) was thinner compared to eyes without pallor (91 ± 14 μm, P < 0.001). Optic nerve pallor predicted RNFL thinning with a sensitivity of 69% and a specificity of 75%. Optic nerve appearance predicted RNFL thinning (with a sensitivity and specificity of 81%) when RNFL had thinned by ∼ 40%. Most patients with pallor had RNFL thinning with (66%) or without (25%) visual field loss; the remainder had normal RNFL and fields (5%) or with visual field abnormalities (4%). Conclusions Optic nerve pallor as a predictor of RNFL thinning showed fair sensitivity and specificity, although it is optimally sensitive/specific only when substantial RNFL loss has occurred. Translational Relevance Finding an acceptable relationship between the optic nerve appearance by ophthalmoscopy and spectral domain-OCT RNFL measures will help the clinician's interpretation of the information provided by this technology, which is gaining momentum in neuro-ophthalmic research. PMID:25374773

Unilateral Superior Laryngeal Nerve Lesion in an Animal Model of Dysphagia and Its Effect on Sucking and Swallowing

PubMed Central

Campbell-Malone, Regina; Holman, Shaina D.; Lukasik, Stacey L.; Fukuhara, Takako; Gierbolini-Norat, Estela M.; Thexton, Allan J.; German, Rebecca Z.

2013-01-01

We tested two hypotheses relating to the sensory deficit that follows a unilateral superior laryngeal nerve (SLN) lesion in an infant animal model. We hypothesized that it would result in (1) a higher incidence of aspiration and (2) temporal changes in sucking and swallowing. We ligated the right-side SLN in six 2–3-week-old female pigs. Using videofluoroscopy, we recorded swallows in the same pre- and post-lesion infant pigs. We analyzed the incidence of aspiration and the duration and latency of suck and swallow cycles. After unilateral SLN lesioning, the incidence of silent aspiration during swallowing increased from 0.7 to 41.5 %. The durations of the suck containing the swallow, the suck immediately following the swallow, and the swallow itself were significantly longer in the post-lesion swallows, although the suck prior to the swallow was not different. The interval between the start of the suck containing a swallow and the subsequent epiglottal movement was longer in the post-lesion swallows. The number of sucks between swallows was significantly greater in post-lesion swallows compared to pre-lesion swallows. Unilateral SLN lesion increased the incidence of aspiration and changed the temporal relationships between sucking and swallowing. The longer transit time and the temporal coordinative dysfunction between suck and swallow cycles may contribute to aspiration. These results suggest that swallow dysfunction and silent aspiration are common and potentially overlooked sequelae of unilateral SLN injury. This validated animal model of aspiration has the potential for further dysphagia studies. PMID:23417250

Unilateral nasal pain with migraine features.

PubMed

Alvarez, Mónica; Montojo, Teresa; de la Casa, Beatriz; Vela, Lydia; Pareja, Juan A

2013-09-01

Migraine attacks exclusively felt in the face are very rare, the pain involving the territories supplied by the second and third branches of the trigeminal nerve. Two patients suffering from heminasal pain attacks accompanied with typical migrainous features and responsive to oral or intranasal triptans - but not to intranasal lidocaine or oxymetazoline. In one patient, the attacks could be precipitated upon slight touching on the tip of the nose, in the other attacks were preceded by the nasal sensation typically heralding sneezing. Migraine pain mostly develops within the innervation territory of the first branch of the trigeminal nerve, which includes the nose. Therefore, episodes of unilateral nasal pain with migrainous features could be considered a migraine with unusual topography (nasal migraine). Painful nasal attacks occasionally preceded by stimulation of trigeminal afferents in the nose, could be conceived of as migraine-tic syndrome.

Abducens Nerve in Patients with Type 3 Duane’s Retraction Syndrome

PubMed Central

Hwang, Jeong-Min

2016-01-01

Background We have previously reported that the presence of the abducens nerve was variable in patients with type 3 Duane’s retraction syndrome (DRS), being present in 2 of 5 eyes (40%) and absent in 3 (60%) on magnetic resonance imaging (MRI). The previous study included only 5 eyes with unilateral DRS type 3. Objectives To supplement existing scarce pathologic information by evaluating the presence of the abducens nerve using high resolution thin-section MRI system in a larger number of patients with DRS type 3, thus to provide further insight into the pathogenesis of DRS. Data Extraction A retrospective review of medical records on ophthalmologic examination and high resolution thin-section MRI at the brainstem level and orbit was performed. A total of 31 patients who showed the typical signs of DRS type 3, including abduction and adduction deficit, globe retraction, narrowing of fissure on adduction and upshoot and/or downshoot, were included. The abducens nerve and any other extraocular muscle abnormalities discovered by MRI were noted. Results DRS was unilateral in 26 patients (84%) and bilateral in 5 patients (16%). Two out of 5 bilateral patients had DRS type 3 in the right eye and DRS type 1 in the left eye. Of the 34 affected orbits with DRS type 3 in 31 patients, the abducens nerve was absent or hypoplastic in 31 eyes (91%) and present in 3 eyes (9%). Patients with a present abducens nerve showed more limitation in adduction compared to patients with an absent abducens nerve (P = 0.030). Conclusions The abducens nerve is absent or hypoplastic in 91% of DRS type 3. Patients with a present abducens nerve showed more prominent limitation of adduction. As DRS type 3 partly share the same pathophysiology with type 1 and 2 DRS, the classification of DRS may have to be revised according to MRI findings. PMID:27352171

Sacral nerve stimulation enhances epithelial barrier of the rectum: results from a porcine model.

PubMed

Meurette, G; Blanchard, C; Duchalais-Dassonneville, E; Coquenlorge, S; Aubert, P; Wong, M; Lehur, P-A; Neunlist, M

2012-03-01

The mechanism of action of sacral nerve stimulation (SNS) remains largely elusive. The aims of this study were to develop a clinically relevant animal model for percutaneous SNS and to describe its effect on the epithelial barrier of the rectum. Under general anesthesia and after percutaneous electrode placement for S3 nerve root stimulation, six pigs underwent unilateral stimulation and six bilateral stimulation. Animals were stimulated for 3 h using an external pulse generator (1-2.5 V; 14 Hz; 210 μs). Six animals underwent electrode implantation without stimulation and served as controls. Full-thickness rectal biopsies were performed prior to and after stimulation. Paracellular permeability was evaluated by measuring sulfonic acid flux across the rectal mucosa in Ussing chambers. Histological assessment of mucosal thickness, epithelial desquamation, and mucus expression were performed. Percutaneous stimulation resulted in successful anal contractions whose amplitude and uniformity was enhanced following bilateral compared with unilateral stimulation. In controls, paracellular permeability significantly increased during the stimulation period whereas it remained unchanged following unilateral stimulation. In contrast, permeability was significantly reduced by bilateral stimulation. This effect was associated with a concomitant reduction in mucosal thickness and a trend toward increased amount of mucus on surface epithelium compared with controls. The development of a porcine model of percutaneous SNS revealed the ability of neuromodulation to reinforce rectal epithelial barrier. Furthermore, our results suggest that SNS could be used for treatment of gastrointestinal pathologies with reduced rectal mucosal barrier functions. © 2012 Blackwell Publishing Ltd.

Bilateral widespread mechanical pain sensitivity in carpal tunnel syndrome: evidence of central processing in unilateral neuropathy.

PubMed

Fernández-de-las-Peñas, César; de la Llave-Rincón, Ana Isabel; Fernández-Carnero, Josué; Cuadrado, María Luz; Arendt-Nielsen, Lars; Pareja, Juan A

2009-06-01

The aim of this study was to investigate whether bilateral widespread pressure hypersensitivity exists in patients with unilateral carpal tunnel syndrome. A total of 20 females with carpal tunnel syndrome (aged 22-60 years), and 20 healthy matched females (aged 21-60 years old) were recruited. Pressure pain thresholds were assessed bilaterally over median, ulnar, and radial nerve trunks, the C5-C6 zygapophyseal joint, the carpal tunnel and the tibialis anterior muscle in a blinded design. The results showed that pressure pain threshold levels were significantly decreased bilaterally over the median, ulnar, and radial nerve trunks, the carpal tunnel, the C5-C6 zygapophyseal joint, and the tibialis anterior muscle in patients with unilateral carpal tunnel syndrome as compared to healthy controls (all, P < 0.001). Pressure pain threshold was negatively correlated to both hand pain intensity and duration of symptoms (all, P < 0.001). Our findings revealed bilateral widespread pressure hypersensitivity in subjects with carpal tunnel syndrome, which suggest that widespread central sensitization is involved in patients with unilateral carpal tunnel syndrome. The generalized decrease in pressure pain thresholds associated with pain intensity and duration of symptoms supports a role of the peripheral drive to initiate and maintain central sensitization. Nevertheless, both central and peripheral sensitization mechanisms are probably involved at the same time in carpal tunnel syndrome.

Transtympanic Facial Nerve Paralysis: A Review of the Literature

PubMed Central

Schaefer, Nathan; O’Donohue, Peter; French, Heath; Griffin, Aaron; Gochee, Peter

2015-01-01

Summary: Facial nerve paralysis because of penetrating trauma through the external auditory canal is extremely rare, with a paucity of published literature. The objective of this study is to review the literature on transtympanic facial nerve paralysis and increase physician awareness of this uncommon injury through discussion of its clinical presentation, management and prognosis. We also aim to improve patient outcomes in those that have sustained this type of injury by suggesting an optimal management plan. In this case report, we present the case of a 46-year-old white woman who sustained a unilateral facial nerve paresis because of a garfish penetrating her tympanic membrane and causing direct damage to the tympanic portion of her facial nerve. On follow-up after 12 months, her facial nerve function has largely returned to normal. Transtympanic facial nerve paralysis is a rare injury but can have a favorable prognosis if managed effectively. PMID:26090278

A history of the optic nerve and its diseases.

PubMed

Reeves, C; Taylor, D

2004-11-01

We will trace the history of ideas about optic nerve anatomy and function in the Western world from the ancient Greeks to the early 20th century and show how these influenced causal theories of optic nerve diseases. Greek and Roman humoral physiology needed a hollow optic nerve, the obstruction of which prevented the flow of visual spirit to and from the brain and resulted in blindness. Medieval physicians understood that the presence of a fixed dilated pupil indicated optic nerve obstruction, preventing the passage of visual spirit, and that cataract surgery in such cases would not restore sight. During the Renaissance, the organ of vision was transferred from the lens to the optic nerve, which was generally believed to be on the axis of the eye. The acuity of central vision (at the optic disc) was explained by the concentration of visual spirit where the optic nerve met the retina. The growth of anatomy and influence of mechanical philosophy from the 17th century led to visual spirit being replaced with the concept of nerve force, which later became associated with electricity travelling along nerve fibres. This coincided with discourse about the nature of the nervous system and a shift in orientation from understanding illness holistically in terms of an individual's humoral imbalance to the concept of organ-based diseases. Both the microscope and the ophthalmoscope allowed visualisation of the optic nerve, but problems of interpretation persisted until conceptual transformations in medical science were made.

Quantitative characterization of optic nerve atrophy in patients with multiple sclerosis

PubMed Central

Smith, Alex K; Lyttle, Bailey; Box, Bailey; Landman, Bennett A; Bagnato, Francesca; Pawate, Siddharama; Smith, Seth A

2017-01-01

Background Optic neuritis (ON) is one of the most common presentations of multiple sclerosis (MS). Magnetic resonance imaging (MRI) of the optic nerves is challenging because of retrobulbar motion, orbital fat and susceptibility artifacts from maxillary sinuses; therefore, axonal loss is investigated with the surrogate measure of a single heuristically defined point along the nerve as opposed to volumetric investigation. Objective The objective of this paper is to derive optic nerve volumetrics along the entire nerve length in patients with MS and healthy controls in vivo using high-resolution, clinically viable MRI. Methods An advanced, isotropic T2-weighted turbo spin echo MRI was applied to 29 MS patients with (14 patients ON+) or without (15 patients ON–) history of ON and 42 healthy volunteers. An automated tool was used to estimate and compare whole optic nerve and surrounding cerebrospinal fluid radii along the length of the nerve. Results and conclusion Only ON+ MS patients had a significantly reduced optic nerve radius compared to healthy controls in the central segment of the optic nerve. Using clinically available MRI methods, we show and quantify ON volume loss for the first time in MS patients. PMID:28932410

A case of bilateral lower cranial nerve palsies after base of skull trauma with complex management issues: case report and review of the literature.

PubMed

Lehn, Alexander Christoph; Lettieri, Jennie; Grimley, Rohan

2012-05-01

Fractures of the skull base can cause lower cranial nerve palsies because of involvement of the nerves as they traverse the skull. A variety of syndromes have been described, often involving multiple nerves. These are most commonly unilateral, and only a handful of cases of bilateral cranial nerve involvement have been reported. We describe a 64-year-old man with occipital condylar fracture complicated by bilateral palsies of IX and X nerves associated with dramatic physiological derangement causing severe management challenges. Apart from debilitating postural hypotension, he developed dysphagia, severe gastrointestinal dysmotility, issues with airway protection as well as airway obstruction, increased oropharyngeal secretions and variable respiratory control. This is the first report of a patient with traumatic bilateral cranial nerve IX and X nerve palsies. This detailed report and the summary of all 6 previous case reports of traumatic bilateral lower cranial nerve palsies illustrate clinical features, treatment strategies, and outcomes of these rare events.

The influence of unilateral saccular impairment on functional balance performance and self-report dizziness.

PubMed

McCaslin, Devin L; Jacobson, Gary P; Grantham, Sarah L; Piker, Erin G; Verghese, Susha

2011-09-01

Postural stability in humans is largely maintained by vestibular, visual, and somatosensory inputs to the central nervous system. Recent clinical advances in the assessment of otolith function (e.g., cervical and ocular vestibular evoked myogenic potentials [cVEMPs and oVEMPs], subjective visual vertical [SVV] during eccentric rotation) have enabled investigators to identify patients with unilateral otolith impairments. This research has suggested that patients with unilateral otolith impairments perform worse than normal healthy controls on measures of postural stability. It is not yet known if patients with unilateral impairments of the saccule and/or inferior vestibular nerve (i.e., unilaterally abnormal cVEMP) perform differently on measures of postural stability than patients with unilateral impairments of the horizontal SCC (semicircular canal) and/or superior vestibular nerve (i.e., unilateral caloric weakness). Further, it is not known what relationship exists, if any, between otolith system impairment and self-report dizziness handicap. The purpose of this investigation was to determine the extent to which saccular impairments (defined by a unilaterally absent cVEMP) and impairments of the horizontal semicircular canal (as measured by the results of caloric testing) affect vestibulospinal function as measured through the Sensory Organization Test (SOT) of the computerized dynamic posturography (CDP). A secondary objective of this investigation was to measure the effects, if any, that saccular impairment has on a modality-specific measure of health-related quality of life. A retrospective cohort study. Subjects were assigned to one of four groups based on results from balance function testing: Group 1 (abnormal cVEMP response only), Group 2 (abnormal caloric response only), Group 3 (abnormal cVEMP and abnormal caloric response), and Group 4 (normal control group). Subjects were 92 adult patients: 62 were seen for balance function testing due to complaints of dizziness, vertigo, or unsteadiness, and 30 served as controls. All subjects underwent videonystagmography or electronystagmography (VNG/ENG), vestibular evoked myogenic potentials (VEMPs), self-report measures of self-perceived dizziness disability/handicap (Dizziness Handicap Inventory), and tests of postural control (Neurocom Equitest). Subjects were categorized into one of four groups based on balance function test results. All variables were subjected to a multifactor analysis of variance (ANOVA). The Dizziness Handicap Inventory (DHI) total scores and equilibrium scores served as the dependent variables. Results showed that patients with abnormal unilateral saccular or inferior vestibular nerve function (i.e., abnormal cVEMP) demonstrated significantly impaired postural control when compared to normal participants. However, this group demonstrated significantly better postural stability when compared to the group with abnormal caloric responses alone and the group with abnormal caloric responses and abnormal cVEMP results. Patients with an abnormal cVEMP did not differ significantly on the DHI compared to the other two impaired groups. We interpret these findings as evidence that a significantly asymmetrical cVEMP in isolation negatively impacts performance on measures of postural control compared to normal subjects but not compared to patients with significant caloric weaknesses. However, patients with a unilaterally abnormal cVEMP do not differ from patients with significant caloric weaknesses in regard to self-perceived dizziness handicap. American Academy of Audiology.

Relationship Between Laryngeal Electromyography and Video Laryngostroboscopy in Vocal Fold Paralysis.

PubMed

Maamary, Joel A; Cole, Ian; Darveniza, Paul; Pemberton, Cecilia; Brake, Helen Mary; Tisch, Stephen

2017-09-01

The objective of this study was to better define the relationship of laryngeal electromyography and video laryngostroboscopy in the diagnosis of vocal fold paralysis. Retrospective diagnostic cohort study with cross-sectional data analysis METHODS: Data were obtained from 57 patients with unilateral vocal fold paralysis who attended a large tertiary voice referral center. Electromyographic findings were classified according to recurrent laryngeal nerve, superior laryngeal nerve, and high vagal/combined lesions. Video laryngostroboscopy recordings were classified according to the position of the immobile fold into median, paramedian, lateral, and a foreshortened/hooded vocal fold. The position of the paralyzed vocal fold was then analyzed according to the lesion as determined by electromyography. The recurrent laryngeal nerve was affected in the majority of cases with left-sided lesions more common than right. Vocal fold position differed between recurrent laryngeal and combined vagal lesions. Recurrent laryngeal nerve lesions were more commonly associated with a laterally displaced immobile fold. No fold position was suggestive of a combined vagal lesion. The inter-rater reliability for determining fold position was high. Laryngeal electromyography is useful in diagnosing neuromuscular dysfunction of the larynx and best practice recommends its continued implementation along with laryngostroboscopy. While recurrent laryngeal nerve lesions are more likely to present with a lateral vocal fold, this does not occur in all cases. Such findings indicate that further unknown mechanisms contribute to fold position in unilateral paralysis. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Regenerating Fish Optic Nerves and a Regeneration-Like Response in Injured Optic Nerves of Adult Rabbits

NASA Astrophysics Data System (ADS)

Schwartz, M.; Belkin, M.; Harel, A.; Solomon, A.; Lavie, V.; Hadani, M.; Rachailovich, I.; Stein-Izsak, C.

1985-05-01

Regeneration of fish optic nerve (representing regenerative central nervous system) was accompanied by increased activity of regeneration-triggering factors produced by nonneuronal cells. A graft of regenerating fish optic nerve, or a ``wrap-around'' implant containing medium conditioned by it, induced a response associated with regeneration in injured optic nerves of adult rabbits (representing a nonregenerative central nervous system). This response was manifested by an increase of general protein synthesis and of selective polypeptides in the retinas and by the ability of the retina to sprout in culture.

Optic Nerve Imaging

MedlinePlus

... About Us Donate In This Section Optic Nerve Imaging email Send this article to a friend by ... may use one of these optic nerve computer imaging techniques as part of your glaucoma examination. By ...

High-resolution matrix-assisted laser desorption ionization–imaging mass spectrometry of lipids in rodent optic nerve tissue

PubMed Central

Anderson, David M. G.; Mills, Daniel; Spraggins, Jeffrey; Lambert, Wendi S.; Calkins, David J.

2013-01-01

Purpose To develop a method for generating high spatial resolution (10 µm) matrix-assisted laser desorption ionization (MALDI) images of lipids in rodent optic nerve tissue. Methods Ice-embedded optic nerve tissue from rats and mice were cryosectioned across the coronal and sagittal axes of the nerve fiber. Sections were thaw mounted on gold-coated MALDI plates and were washed with ammonium acetate to remove biologic salts before being coated in 2,5-dihydroxybenzoic acid by sublimation. MALDI images were generated in positive and negative ion modes at 10 µm spatial resolution. Lipid identification was performed with a high mass resolution Fourier transform ion cyclotron resonance mass spectrometer. Results Several lipid species were observed with high signal intensity in MALDI images of optic nerve tissue. Several lipids were localized to specific structures including in the meninges surrounding the optic nerve and in the central neuronal tissue. Specifically, phosphatidylcholine species were observed throughout the nerve tissue in positive ion mode while sulfatide species were observed in high abundance in the meninges surrounding the optic nerve in negative ion mode. Accurate mass measurements and fragmentation using sustained off-resonance irradiation with a high mass resolution Fourier transform ion cyclotron resonance mass spectrometer instrument allowed for identification of lipid species present in the small structure of the optic nerve directly from tissue sections. Conclusions An optimized sample preparation method provides excellent sensitivity for lipid species present within optic nerve tissue. This allowed the laser spot size and fluence to be reduced to obtain a high spatial resolution of 10 µm. This new imaging modality can now be applied to determine spatial and molecular changes in optic nerve tissue with disease. PMID:23559852

Evaluation of acute radiation optic neuropathy by B-scan ultrasonography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lovato, A.A.; Char, D.H.; Quivey, J.M.

1990-09-15

We studied the accuracy of B-scan ultrasonography to diagnose radiation-induced optic neuropathy in 15 patients with uveal melanoma. Optic neuropathy was diagnosed by an observer masked as to clinical and photographic data. We analyzed planimetry area measurements of the retrobulbar nerve before and after irradiation. The retrobulbar area of the optic nerve shadow on B-scan was quantitated with a sonic digitizer. Increased optic nerve shadow area was confirmed in 13 of 15 patients who had radiation optic neuropathy (P less than .004). The correct diagnosis was confirmed when the results of ultrasound were compared to fundus photography and fluorescein angiography.more » In 13 patients there was acute radiation optic neuropathy. Two patients did not show an enlarged retrobulbar optic nerve, and the clinical appearance suggested early progression to optic atrophy. Ultrasonography documents the enlargement of the optic nerve caused by acute radiation changes.« less

Optic neuritis

MedlinePlus

... optic neuritis is unknown. The optic nerve carries visual information from your eye to the brain. The nerve can swell when it becomes suddenly ... may include: Color vision testing MRI of the brain , including special images of the optic nerve Visual acuity testing Visual field testing Examination of the ...

Framework Surgery for Treatment of Unilateral Vocal Fold Paralysis

PubMed Central

Daniero, James J.; Garrett, C. Gaelyn; Francis, David O.

2014-01-01

Laryngeal framework surgery is the current gold standard treatment for unilateral vocal fold paralysis. It provides a permanent solution to glottic insufficiency caused by injury to the recurrent laryngeal nerve. Various modifications to the original Isshiki type I laryngoplasty procedure have been described to improve voice and swallowing outcomes. The success of this procedure is highly dependent on the experience of the surgeon as it epitomizes the intersection of art and science in the field. The following article reviews the evidence, controversies, and complications related to laryngoplasty for unilateral vocal fold paralysis. It also provides a detailed analysis of how and when arytenoid-positioning procedures should be considered, and summarizes the literature on postoperative outcomes. PMID:24883239

Neurophysiological intraoperative monitoring during an optic nerve schwannoma removal.

PubMed

San-Juan, Daniel; Escanio Cortés, Manuel; Tena-Suck, Martha; Orozco Garduño, Adolfo Josué; López Pizano, Jesús Alejandro; Villanueva Domínguez, Jonathan; Fernández Gónzalez-Aragón, Maricarmen; Gómez-Amador, Juan Luis

2017-10-01

This paper reports the case of a patient with optic nerve schwannoma and the first use of neurophysiological intraoperative monitoring of visual evoked potentials during the removal of such tumor with no postoperative visual damage. Schwannomas are benign neoplasms of the peripheral nervous system arising from the neural crest-derived Schwann cells, these tumors are rarely located in the optic nerve and the treatment consists on surgical removal leading to high risk of damage to the visual pathway. Case report of a thirty-year-old woman with an optic nerve schwannoma. The patient underwent surgery for tumor removal on the left optic nerve through a left orbitozygomatic approach with intraoperative monitoring of left II and III cranial nerves. We used Nicolet Endeavour CR IOM (Carefusion, Middleton WI, USA) to performed visual evoked potentials stimulating binocularly with LED flash goggles with the patient´s eyes closed and direct epidural optic nerve stimulation delivering rostral to the tumor a rectangular current pulse. At follow up examinations 7 months later, the left eye visual acuity was 20/60; Ishihara score was 8/8 in both eyes; the right eye photomotor reflex was normal and left eye was mydriatic and arreflectic; optokinetic reflex and ocular conjugate movements were normal. In this case, the epidural direct electrical stimulation of optic nerve provided stable waveforms during optic nerve schwannoma resection without visual loss.

Novel Model of Somatosensory Nerve Transfer in the Rat.

PubMed

Paskal, Adriana M; Paskal, Wiktor; Pelka, Kacper; Podobinska, Martyna; Andrychowski, Jaroslaw; Wlodarski, Pawel K

2018-05-09

Nerve transfer (neurotization) is a reconstructive procedure in which the distal denervated nerve is joined with a proximal healthy nerve of a less significant function. Neurotization models described to date are limited to avulsed roots or pure motor nerve transfers, neglecting the clinically significant mixed nerve transfer. Our aim was to determine whether femoral-to-sciatic nerve transfer could be a feasible model of mixed nerve transfer. Three Sprague Dawley rats were subjected to unilateral femoral-to-sciatic nerve transfer. After 50 days, functional recovery was evaluated with a prick test. At the same time, axonal tracers were injected into each sciatic nerve distally to the lesion site, to determine nerve fibers' regeneration. In the prick test, the rats retracted their hind limbs after stimulation, although the reaction was moderately weaker on the operated side. Seven days after injection of axonal tracers, dyes were visualized by confocal microscopy in the spinal cord. Innervation of the recipient nerve originated from higher segments of the spinal cord than that on the untreated side. The results imply that the femoral nerve axons, ingrown into the damaged sciatic nerve, reinnervate distal targets with a functional outcome.

Fulminant bilateral papilloedema during low-dose steroid taper in a child with systemic idiopathic arthritis treated with tocilizumab.

PubMed

Burstzyn, Lulu; Levin, Simon; Rotenberg, Brian; Van Hooren, Tamara; Leung, Andrew; Berard, Roberta; Ardelean, Daniela S

2017-01-01

Systemic juvenile idiopathic arthritis (SJIA) is one of the most severe forms of arthritis that affects children younger than 16 years of age at onset. SJIA often requires corticosteroids to control the inflammation. However, long-term corticosteroid use may have adverse effects, including intracranial hypertension (IH). Biologic therapies have been used as corticosteroid sparing agents. We report the first case of a child with steroid-dependent SJIA treated with tocilizumab, an IL-6 receptor monoclonal antibody, who developed fulminant IH, bilateral papilloedema and vision loss when oral prednisone was weaned from 2 to 1 mg per day. Despite repeated lumbar punctures and high dose acetazolamide, he required urgent unilateral optic nerve sheath fenestration (ONSF). This endoscopic surgical intervention released the pressure exerted by the cerebrospinal fluid on the optic nerve and stopped the progression of vision loss. Nine weeks after the diagnosis of bilateral papilloedema, his vision was completely restored in one eye and partially recovered in the contralateral one. Long-term treatment with corticosteroids even at very low dose and tocilizumab may predispose to severe IH, papilloedema and vision loss. The role that tocilizumab might have played in this case in unclear. Early recognition and prompt treatment of papilloedema is crucial in avoiding permanent vision loss. Fulminant papilloedema in an immunocompromised child carries additional significant challenges. Early ONSF is a safe and effective intervention in refractory papilloedema. Children with severe papilledema secondary to IH should be managed by a multidisciplinary team in tertiary centres.

Novel use of narrow paddle electrodes for occipital nerve stimulation--technical note.

PubMed

Abhinav, Kumar; Park, Nicholas D; Prakash, Savithru K; Love-Jones, Sarah; Patel, Nikunj K

2013-01-01

Occipital nerve stimulation (ONS), an established treatment for medically intractable headache syndromes, has lead migration rates quoted up to 24%. In a series of patients with ideal characteristics for this treatment modality, we describe an operative technique for ONS involving the novel use of narrow paddle electrodes: "S8 Lamitrode" (St. Jude Medical [SJM], St. Paul, MN, USA). Five patients (occipital neuralgia [ON] = 4; chronic migraine [CM] = 1) were treated with ONS between 2010 and 2011. All patients had a successful trial of peripheral neurostimulation (Algotec Ltd, Crawley, UK) therapy. Operative technique involved the use of a park-bench position, allowing simultaneous exposure of the occipital and infraclavicular regions. Through a retromastoid/occipital incision just beneath the external occipital protruberance, exposing the extrafascial plane, the S8 Lamitrode is implanted to intersect both greater occipital nerves for bilateral pain or unilateral greater and lesser occipital nerves for unilateral ON or with significant component of the pain relating to the lesser occipital nerve. Over the median follow-up of 12 months, there were no episodes of lead migration or revision. There also was significant improvement in symptoms in all patients. This is the first reported use of S8 Lamitrode electrode for ONS. This narrow electrode is suited for this role leading to minimal trauma during surgical placement, facilitates resolution of problems with lead migration, and optimizes effect with stimulation focused more in direction of the occipital nerves without skin involvement. To date, the SJM Genesis neurostimulation system, with percutaneous electrodes only, is CE mark approved in Europe for peripheral nerve stimulation of the occipital nerves for the management of pain and disability for patients diagnosed with intractable CM. Further developments and studies are required for better devices to suit ONS, thereby avoiding frequently encountered problems and which may clarify the role of paddle leads in ONS. © 2012 International Neuromodulation Society.

Recovery of function, peripheral sensitization and sensory neurone activation by novel pathways following axonal injury in Aplysia californica.

PubMed

Dulin, M F; Steffensen, I; Morris, C E; Walters, E T

1995-10-01

Recovery of behavioural and sensory function was examined following unilateral pedal nerve crush in Aplysia californica. Nerve crush that transected all axons connecting the tail to the central nervous system (CNS) eliminated the ipsilateral tail-evoked siphon reflex, whose sensory input travels in the crushed tail nerve (p9). The first reliable signs of recovery of this reflex were observed within 1 week, and most animals displayed tail-evoked siphon responses within 2 weeks. Wide-dynamic-range mechanosensory neurons with somata in the ventrocaudal (VC) cluster of the ipsilateral pleural ganglion exhibited a few receptive fields (RFs) on the tail 3 weeks after unilateral pedal nerve crush, indicating that the RFs had either regenerated or been reconnected to the central somata. These RFs were smaller and sensitized compared with corresponding RFs on the contralateral, uncrushed side. Centrally conducted axon responses of VC sensory neurones to electrical stimulation distal to the nerve crush site did not reappear until at least 10 days after the crush. Because the crush site was much closer to the CNS than to the tail, the failure of axon responses to be restored earlier than the behavioural responses indicates that early stages of reflex recovery are not due to regeneration of VC sensory neurone axons into the tail. Following nerve crush, VC sensory neurones often could be activated by stimulating central connectives or peripheral nerves that do not normally contain the sensory neurone's axons. These results suggest that recovery of behavioral function after nerve injury involves complex mechanisms, including regenerative growth of axotomized VC sensory neurones, sensitization of regenerating RFs and sprouting of VC sensory neurone fibres within the CNS. Furthermore, the rapidity of behavioural recovery indicates that its initial phases are mediated by additional mechanisms, perhaps centripetal regeneration of unidentified sensory neurones having peripheral somata, or transient reconnection of proximal and distal stumps of axotomized VC cells.

Haemodilution and head-down tilting induce functional injury in the rat optic nerve: A model for peri-operative ischemic optic neuropathy.

PubMed

Roth, Steven; Dreixler, John; Newman, Nancy J

2018-05-15

Mechanisms of peri-operative ischaemic optic neuropathy remain poorly understood. Both specific pre-operative and intra-operative factors have been examined by retrospective studies, but no animal model currently exists. To develop a rodent model of peri-operative ischaemic optic neuropathy. In rats, we performed head-down tilt and/or haemodilution, theorising that the combination damages the optic nerve. Animal study. Laboratory. A total of 36 rats, in four groups, completed the functional examination of retina and optic nerve after the interventions. Anaesthetised groups (n>8) were supine (SUP) for 5 h, head-down tilted 70° for 5 h, head-down tilted/haemodiluted for 5 h or SUP/haemodiluted for 5 h. We measured blood pressure, heart rate, intra-ocular pressure and maintained constant temperature. Retinal function (electroretinography), scotopic threshold response (STR) (for retinal ganglion cells) and visual evoked potentials (VEP) (for transmission through the optic nerve). We imaged the optic nerve in vivo and evaluated retinal histology, apoptotic cells and glial activation in the optic nerve. Retinal and optic nerve function were followed to 14 and 28 days after experiments. At 28 days in head down tilted/haemodiluted rats, negative STR decreased (about 50% amplitude reduction, P = 0.006), VEP wave N2-P3 decreased (70% amplitude reduction, P = 0.01) and P2 latency increased (35%, P = 0.003), optic discs were swollen and glial activation was present in the optic nerve. SUP/haemodiluted rats had decreases in negative STR and increased VEP latency, but no glial activation. An injury partly resembling human ischaemic optic neuropathy can be produced in rats by combining haemodilution and head-down tilt. Significant functional changes were also present with haemodilution alone. Future studies with this partial optic nerve injury may enable understanding of mechanisms of peri-operative ischaemic optic neuropathy and could help discover preventive or treatment strategies.

The distinct optic disk and peripapillary appearance in Donnai-Barrow syndrome.

PubMed

Khan, Arif O; Ghazi, Nicola G

2018-06-01

Biallelic mutations in low-density lipoprotein-related protein 2 (LRP2) cause the multi-system Donnai-Barrow syndrome (facio-oculo-acoustico-renal syndrome). Although Donnai-Barrow syndrome is recognized as a form of vitreo-retinopathy, the ocular phenotype has not been well defined. The purpose of this study is to document the disk and peripapillary appearance in Donnai-Barrow syndrome. Retrospective cases series (five children with low vision from a consanguineous Emirati family known to harbor LRP2 mutation (NM_004525.2: c.7564T>C; p.Y42522H)). All five children had high myopia (spherical equivalent from -15 to -22). One had an ophthalmic phenotypic pathognomonic for Knobloch syndrome, and genetic testing confirmed a homozygous novel COL18A1 mutation (NM_130455.3: c.2978_2987del; p.Pro993Leufs*35) with heterozygosity for the LRP2 mutation. The other four children, confirmed to be homozygous for the LRP2 mutation, had hypertelorism and down-slanting palpebral fissures. Three had spontaneous retinal detachment (two bilateral and one unilateral) with complicated post-surgical courses following retinal detachment repair. The three eyes (two children) without retinal detachment had a consistent unique optic nerve head appearance, with thin emanating vessels and multiple rings of depigmentation that made it difficult to discern the edge of the apparently small and recessed neuroretinal rim. This distinct appearance was also present in the post-surgical eyes which were not phthisical and seemed present in the single published posterior pole image found during literature review. A distinctive optic nerve head dysgenesis is part of Donnai-Barrow syndrome and can help distinguish its ocular phenotype from other vitreo-retinopathies associated with high myopia.

Analysis of optic disc change using the heidelberg retina tomograph in an acquired pit of the optic nerve.

PubMed

Oh, Joo Youn; Park, Ki Ho

2004-01-01

A 51-year-old woman diagnosed as having normal-tension glaucoma developed an acquired pit of the optic nerve. The optic disc was viewed by the Heidelberg Retina Tomograph (HRT; Heidelberg Engineering, Heidelberg, Germany) before and after development of an acquired pit of the optic nerve. HRT parameters and cross-sectional images of the optic disc were compared. Maximum cup depth at the site of the acquired pit of the optic nerve increased after development of the acquired pit of the optic nerve (from 1.200 to 2.432 mm). The neuroretinal rim area and volume in the inferotemporal octant were reduced (rim area from 0.070 to 0.010 mm2, rim volume from 0.009 to 0.001 mm3). The morphologic changes in the optic disc were also detected topographically and reflectively.

Optic Nerve Assessment Using 7-Tesla Magnetic Resonance Imaging.

PubMed

Singh, Arun D; Platt, Sean M; Lystad, Lisa; Lowe, Mark; Oh, Sehong; Jones, Stephen E; Alzahrani, Yahya; Plesec, Thomas

2016-04-01

The purpose of this study was to correlate high-resolution magnetic resonance imaging (MRI) and histologic findings in a case of juxtapapillary choroidal melanoma with clinical evidence of optic nerve invasion. With institutional review board approval, an enucleated globe with choroidal melanoma and optic nerve invasion was imaged using a 7-tesla MRI followed by histopathologic evaluation. Optical coherence tomography, B-scan ultrasonography, and 1.5-tesla MRI of the orbit (1-mm sections) could not detect optic disc invasion. Ex vivo, 7-tesla MRI detected optic nerve invasion, which correlated with histopathologic features. Our case demonstrates the potential to document the existence of optic nerve invasion in the presence of an intraocular tumor, a feature that has a major bearing on decision making, particularly for consideration of enucleation.

Eye Involvement in TSC

MedlinePlus

... what we see to the brain via the optic nerve. Retinal and optic nerve involvement in TSC are well known today, ... hamartomas (non-cancerous tumors) of the retina or optic nerve. The most common type of retinal hamartoma ...

Sciatic Nerve Stimulation and its Effects on Upper Airway Resistance in the Anesthetized Rabbit Model Relevant to Sleep Apnea.

PubMed

Schiefer, Matthew; Gamble, Jenniffer; Strohl, Kingman Perkins

2018-06-07

Obstructive sleep apnea (OSA) is a disorder characterized by collapse of the velopharynx and/or oropharynx during sleep when drive to the upper airway is reduced. Here, we explore an indirect approach for activation of upper airway muscles which might affect airway dynamics- unilateral electrical stimulation of the afferent fibers of the sciatic nerve- in an anesthetized rabbit model. A nerve cuff electrode was placed around the sciatic and hypoglossal nerves to deliver stimulus while air flow, air pressure, and alae nasi electromyogram (EMG) were monitored both prior to and after sciatic transection. Sciatic nerve stimulation increased respiratory effort, rate, and alae nasi EMG, which persisted for seconds after stimulation; however, upper airway resistance was unchanged. Hypoglossal stimulation reduced resistance without altering drive. While sciatic nerve stimulation is not ideal for treating obstructive sleep apnea, it remains a target for altering respiratory drive.

Hindlimb spasticity after unilateral motor cortex lesion in rats is reduced by contralateral nerve root transfer.

PubMed

Zong, Haiyang; Ma, Fenfen; Zhang, Laiyin; Lu, Huiping; Gong, Jingru; Cai, Min; Lin, Haodong; Zhu, Yizhun; Hou, Chunlin

2016-12-01

Lower extremity spasticity is a common sequela among patients with acquired brain injury. The optimum treatment remains controversial. The aim of our study was to test the feasibility and effectiveness of contralateral nerve root transfer in reducing post stroke spasticity of the affected hindlimb muscles in rats. In our study, we for the first time created a novel animal hindlimb spastic hemiplegia model in rats with photothrombotic lesion of unilateral motor cortex and we established a novel surgical procedure in reducing motor cortex lesion-induced hindlimb spastic hemiplegia in rats. Thirty six rats were randomized into three groups. In group A, rats received sham operation. In group B, rats underwent unilateral hindlimb motor cortex lesion. In group C, rats underwent unilateral hindlimb cortex lesion followed by contralateral L4 ventral root transfer to L5 ventral root of the affected side. Footprint analysis, Hoffmann reflex (H-reflex), cholera toxin subunit B (CTB) retrograde tracing of gastrocnemius muscle (GM) motoneurons and immunofluorescent staining of vesicle glutamate transporter 1 (VGLUT1) on CTB-labelled motoneurons were used to assess spasticity of the affected hindlimb. Sixteen weeks postoperatively, toe spread and stride length recovered significantly in group C compared with group B (P<0.001). H max (H-wave maximum amplitude)/M max (M-wave maximum amplitude) ratio of gastrocnemius and plantaris muscles (PMs) significantly reduced in group C (P<0.01). Average VGLUT1 positive boutons per CTB-labelled motoneurons significantly reduced in group C (P<0.001). We demonstrated for the first time that contralateral L4 ventral root transfer to L5 ventral root of the affected side was effective in relieving unilateral motor cortex lesion-induced hindlimb spasticity in rats. Our data indicated that this could be an alternative treatment for unilateral lower extremity spasticity after brain injury. Therefore, contralateral neurotization may exert a potential therapeutic candidate to improve the function of lower extremity in patients with spastic hemiplegia. © 2016 The Author(s).

Meningiomas involving the optic nerve: technical aspects and outcomes for a series of 50 patients.

PubMed

Margalit, Nevo S; Lesser, Jonathan B; Moche, Jason; Sen, Chandranath

2003-09-01

Surgical strategies and results for 50 patients with meningiomas involving the optic nerves are discussed and evaluated. Factors affecting the degree of resection and patient outcomes are presented. We emphasize our surgical techniques for resection of these tumors and we discuss the advantages of different approaches, depending on the relationship of the tumor to the optic nerves. Data for 50 patients with meningiomas involving the optic nerves who were surgically treated between 1991 and 2002 were reviewed, by using patient files, operative notes, and pre- and postoperative imaging and ophthalmological examination findings. Thirty-one female patients and 19 male patients, with a mean age of 53 years, were treated. Thirty-one patients (62%) underwent complete tumor removal (Simpson Grade 1 or 2), and 19 patients underwent subtotal removal (Grade 4). Factors affecting the grade of resection were tumor size (P = 0.01), location (P = 0.007), and internal carotid artery encasement (P = 0.019). Patients who underwent Grade 1 or 2 resection exhibited a mean tumor size of 3.0 cm, and patients who underwent Grade 4 resection exhibited a mean tumor size of 4.1 cm. Only three patients had residual tumor on the optic nerve; all others had tumor in the cavernous sinus or at the orbital apex or exhibited vascular involvement. Visual outcomes were influenced predominantly by tumor size, preoperative visual function, and optic nerve encasement. Meningiomas that involve the optic nerves require special considerations and surgical techniques. Early decompression of the optic nerve within the bony canal allows identification and separation of the tumor from the nerve, permitting removal of the tumor from this area with minimal manipulation of the optic nerve.

Indications for Direct Laryngoscopic Examination of Vocal Cord Function Prior to Anterior Cervical Surgery

PubMed Central

Nazemi, Alireza; Carmouche, Jonathan; Albert, Todd; Behrend, Caleb

2016-01-01

Recurrent laryngeal nerve palsy (RLNP) is among the most common complications in both thyroid surgeries and anterior approaches to the cervical spine, having both a diverse etiology and presentation. Most bilateral paresis, with subsequent devastating impact on patients, are due to failure to recognize unilateral recurrent laryngeal nerve paralysis and, although rare, are entirely preventable with appropriate history and screening. Recurrent laryngeal nerve palsy has been shown to present asymptomatically in as high as 32% of cases, which yields limitations on exclusively screening with physical examination. Based on the available literature, diagnosis of unilateral RLNP is the critical factor in preventing the occurrence of bilateral RLNP as the surgeon may elect to operate on the injured side to prevent bilateral paresis. Analysis of incidence rates shows postoperative development of unilateral RLNP is 13.1 (95% confidence interval [CI]: 6.1-28.1) and 13.90 (95% CI: 6.6-29.3) times more likely in anterior spine and thyroid surgery, respectively, in comparison with intubation. Currently, there is no consensus on when to order a preoperative laryngoscopic examination prior to anterior cervical spine surgery. The importance of patient history should be emphasized, as it is the basis for indications of preoperative laryngoscopy. Efforts to minimize postoperative complications must be made, especially when considering the rising rate of cervical fusion. This study presents a systematic review of the literature defining key causes of RLNP, with a probability-based protocol to indicate direct laryngoscopy prior to anterior cervical surgery as a screening tool in the prevention of bilateral RLNP. PMID:28255513

Magnetic resonance diffusion tensor imaging of optic nerve and optic radiation in healthy adults at 3T.

PubMed

Sun, Hong-Hong; Wang, Dong; Zhang, Qiu-Juan; Bai, Zhi-Lan; He, Ping

2013-01-01

To investigate the diffusion characteristics of water of optic nerve and optic radiation in healthy adults and its related factors by diffusion tensor imaging (DTI) at 3T. A total of 107 healthy volunteers performed head conventional MRI and bilateral optic nerve and optic radiation DTI. The primary data of DTI was processed by post-processing software of DTI studio 2.3, obtaining fractional anisotropy value, mean diffusivity value, principal engine value, orthogonal engine value by measuring, and analyzed by the SPSS13.0 statistical software. The bilateral optic nerve and optic radiation fibers presented green color in directional encoded color (DEC) maps and presented high signal in fractional anisotropy (FA) maps. The FA value of the left optic nerve was 0.598±0.069 and the right was 0.593±0.065; the mean diffusivity (MD) value of the left optic nerve was (1.324±0.349)×10(-3)mm(2)/s and the right was (1.312±0.350)×10(-3)mm(2)/s; the principal engine value (λ‖) of the left optic nerve was (2.297±0.522)×10(-3)mm(2)/s and the right was (2.277±0.526)×10(-3)mm(2)/s; the orthogonal engine value (λ⊥) of the left optic nerve was (0.838±0.285)×10(-3)mm(2)/s and the right was (0.830±0.280)×10(-3)mm(2)/s; the FA value of the left optic radiation was 0.636±0.057 and the right was 0.628±0.056; the mean diffusivity (MD) value of the left optic radiation was (0.907±0.103)×10(-3)mm(2)/s and the right was (0.889±0.125)×10(-3)mm(2)/s; the principal eigenvalue (λ‖) of the left optic radiation was (1.655±0.210)×10(-3)mm(2)/s and the right was (1.614±0.171)×10(-3)mm(2)/s; the orthogonal enginvalue (λ⊥) of the left optic radiation was (0.531±0.103)×10(-3)mm(2)/s and the right was (0.524±0.152)×10(-3)mm(2)/s. There was no obvious difference between the FA, MD, λ‖, λ⊥ of the bilateral optic radiation and the bilateral optic nerve (P>0.05) and no obvious difference between male and female group. The FA, MD, λ‖, λ⊥ of the bilateral optic radiation and the bilateral optic nerve had no obvious correlations to the age. DTI is sensitive to the optic nerve and radiation and the relevant DTI parameters of the optic nerve and radiation are established preliminarily in this study.

Do bilateral and unilateral greater occipital nerve block effectiveness differ in chronic migraine patients?

PubMed

Ünal-Artık, Hanzade Aybüke; İnan, Levent Ertuğrul; Ataç-Uçar, Ceyla; Yoldaş, Tahir Kurtuluş

2017-06-01

We aimed to compare the effectiveness of bilateral and unilateral block application in chronic migraine patients and whether there were differences in their effectiveness retrospectively. In chronic migraine patients undergoing Greater occipital nerve (GON) block, mean number of days with pain per month before and after block, mean duration of pain in attacks (in hours), and mean Visual Analog Scale (VAS) in attack and pain severity were recorded from files. The patients underwent one block a week for the first 1 month, thereafter one block a month according to GON block protocol used by our institute. Of 41 patients included in the study, 23 underwent unilateral block (group 1) and 18 underwent bilateral block (group 2). In both groups, number of days with migraine decreased significantly in 2 and 3 months as compared to pre-block treatment (P < 0.001). Mean duration of headache decreased in group 2 during treatment (P < 0.001). In group 1, mean duration of headache also decreased but did not differ significantly (P = 0.051). Mean severity of migraine decreased significantly differ in group 1 in 2, 3 months as compared to pre-block treatment (P < 0.001). No differences were observed in frequency, severity and duration of headache between groups during 3-month treatment period. GON block is effective in chronic migraine and bilateral application is no superior over unilateral application.

Somatosensory Projections to Cochlear Nucleus are Up-regulated after Unilateral Deafness

PubMed Central

Zeng, Chunhua; Yang, Ziheng; Shreve, Lauren; Bledsoe, Sanford; Shore, Susan

2012-01-01

The cochlear nucleus (CN) receives innervation from auditory and somatosensory structures, which can be identified using vesicular glutamate transporters, VGLUT1 and VGLUT2. VGLUT1 is highly expressed in the magnocellular ventral CN (VCN), which receives auditory nerve inputs. VGLUT2 is predominantly expressed in the granule cell domain (GCD), which receives non-auditory inputs from somatosensory nuclei, including spinal trigeminal nucleus (Sp5) and cuneate nucleus (Cu). Two weeks after unilateral deafening VGLUT1 is significantly decreased in ipsilateral VCN while VGLUT2 is significantly increased in the ipsilateral GCD (Zeng et al., 2009), putatively reflecting decreased inputs from auditory nerve and increased inputs from non-auditory structures in guinea pigs. Here we wished to determine whether the upregulation of VGLUT2 represents increases in the number of somatosensory projections to the CN that are maintained for longer periods of time. Thus we examined concurrent changes in VGLUT levels and somatosensory projections in the CN using immunohistochemistry combined with anterograde tract tracing three and six weeks following unilateral deafening. The data reveal that unilateral deafness leads to increased numbers of VGLUT2-colabeled Sp5 and Cu projections to the ventral and dorsal CN. These findings suggest that Sp5 and Cu play significant and unique roles in cross-modal compensation and that, unlike after shorter term deafness, neurons in the magnocelluar regions also participate in the compensation. The enhanced glutamatergic somatosensory projections to the CN may play a role in neural spontaneous hyperactivity associated with tinnitus. PMID:23136418

Transient facial nerve paralysis (Bell's palsy) following administration of hepatitis B recombinant vaccine: a case report.

PubMed

Paul, R; Stassen, L F A

2014-01-01

Bell's palsy is the sudden onset of unilateral transient paralysis of facial muscles resulting from dysfunction of the seventh cranial nerve. Presented here is a 26-year-old female patient with right lower motor neurone facial palsy following hepatitis B vaccination. Readers' attention is drawn to an uncommon cause of Bell's palsy, as a possible rare complication of hepatitis B vaccination, and steps taken to manage such a presentation.

Pharmacological Prevention and Reversion of Erectile Dysfunction after Radical Prostatectomy, By Modulation of Nitric Oxide/Cgmp Pathways

DTIC Science & Technology

2008-03-01

Figure 3. Time course of the effect of bilateral cavernosal nerve resection on the smooth muscle cell content in the rat corpora cavernosa. Penile...iindicates the apoptotic cells in the corpora cavernosa. Bottom: QIA for TUNEL ***Pɘ.001 Figure 7: Time course of the effect of bilateral...Figure 6 Effect of unilateral and bilateral cavernosal nerve resection and long-term sildenafil treatment on cell proliferation and turnover in the

Astrocytes in the optic nerve head express putative mechanosensitive channels

PubMed Central

Choi, Hee Joo; Sun, Daniel

2015-01-01

Purpose To establish whether optic nerve head astrocytes express candidate molecules to sense tissue stretch. Methods We used conventional PCR, quantitative PCR, and single-cell reverse transcription PCR (RT–PCR) to assess the expression of various members of the transient receptor potential (TRP) channel family and of the recently characterized mechanosensitive channels Piezo1 and 2 in optic nerve head tissue and in single, isolated astrocytes. Results Most TRP subfamilies (TRPC, TRPM, TRPV, TRPA, and TRPP) and Piezo1 and 2 were expressed in the optic nerve head of the mouse. Quantitative real-time PCR analysis showed that TRPC1, TRPM7, TRPV2, TRPP2, and Piezo1 are the dominant isoforms in each subfamily. Single-cell RT–PCR revealed that many TRP isoforms, TRPC1–2, TRPC6, TRPV2, TRPV4, TRPM2, TRPM4, TRPM6–7, TRPP1–2, and Piezo1–2, are expressed in astrocytes of the optic nerve head, and that most astrocytes express TRPC1 and TRPP1–2. Comparisons of the TRPP and Piezo expression levels between different tissue regions showed that Piezo2 expression was higher in the optic nerve head and the optic nerve proper than in the brain and the corpus callosum. TRPP2 also showed higher expression in the optic nerve head. Conclusions Astrocytes in the optic nerve head express multiple putative mechanosensitive channels, in particular the recently identified channels Piezo1 and 2. The expression of putative mechanosensitive channels in these cells may contribute to their responsiveness to traumatic or glaucomatous injury. PMID:26236150

Optic Nerve Assessment Using 7-Tesla Magnetic Resonance Imaging

PubMed Central

Singh, Arun D.; Platt, Sean M.; Lystad, Lisa; Lowe, Mark; Oh, Sehong; Jones, Stephen E.; Alzahrani, Yahya; Plesec, Thomas

2016-01-01

Purpose The purpose of this study was to correlate high-resolution magnetic resonance imaging (MRI) and histologic findings in a case of juxtapapillary choroidal melanoma with clinical evidence of optic nerve invasion. Methods With institutional review board approval, an enucleated globe with choroidal melanoma and optic nerve invasion was imaged using a 7-tesla MRI followed by histopathologic evaluation. Results Optical coherence tomography, B-scan ultrasonography, and 1.5-tesla MRI of the orbit (1-mm sections) could not detect optic disc invasion. Ex vivo, 7-tesla MRI detected optic nerve invasion, which correlated with histopathologic features. Conclusions Our case demonstrates the potential to document the existence of optic nerve invasion in the presence of an intraocular tumor, a feature that has a major bearing on decision making, particularly for consideration of enucleation. PMID:27239461

Structural changes of macula and optic disk of the fellow eye in patients with nonarteritic anterior ischemic optic neuropathy.

PubMed

Duman, R; Yavas, G F; Veliyev, I; Dogan, M; Duman, R

2018-05-10

The aim was to assess the ganglion cell complex (GCC) thickness, retinal nerve fiber layer (RNFL) thickness and optic disk features in the affected eyes (AE) and unaffected fellow eyes (FE) of subjects with unilateral nonarteritic anterior ischemic optic neuropathy (NAION) and to compare with healthy control eyes (CE) using spectral domain-optical coherence tomography (SD-OCT). This study included 28 patients and age, sex and refraction-matched 28 control subjects. Mean GCC thickness and peripapillary RNFL thickness in four quadrants measured by cirrus SD-OCT were evaluated in both AE and FE of patients and CE. In addition, optic disk measurements obtained with OCT were evaluated. Mean GCC thickness was significantly lower in AE compared with both FE and CE (P < 0.001), and mean GCC thickness in FE was significantly lower than CE (P = 0.022). In addition, mean RNFL thickness in superior and nasal quadrants significantly decreased in FE compared with CE (P = 0.020 and 0.010, respectively). Furthermore, AE had significantly greater optic disk cupping compared with both FE and CE (P < 0.001). GCC and RNFL thickness decreased significantly at late stages of NAION, in both AE and FE compared with CE, suggesting that some subclinical structural changes may occur in FE despite lack of obvious visual symptoms. In addition, there was no significant difference in optic disk features between the CE and FE. And significantly greater optic disk cupping in the AE compared with both FE and CE supports the acquired enlargement of cupping after the onset of NAION.

[Treatment of difficult endocrine orbitopathy cases].

PubMed

Breuer, T; Ammann-Rauch, D; Tasman, A J

2007-05-01

There can be many differences between the clinical presentation and disease development of endocrine orbitopathy. Uncommon clinical expressions of the disease may lead to misinterpretations causing difficulties in treatment. Misdiagnosed forms of the disease can end with irreversible vision loss. A 79-year old female with severe bilateral thyroid eye disease, progressive almost blinding visual loss, with the absence of exophthalmos is described. Second, a 39 year old female with a unilateral thyroid eye disease and relapsing episodes of the disease is reported. Exophthalmos, as a symptom, occurs in about 60 % of the patients diagnosed with thyroid eye disease. The absence of exophthalmos may be due to a reduced volume (atrophy ) of retrobulbar fat tissue. Progressive visual loss can be related to direct compression of the optic nerve by thickened eye muscles in the orbital apex. Thyroid eye disease presents itself unilaterally in 5-11 % of all cases and involvement of the contra lateral orbit may occur years later. A relapse of the disease may be triggered by episodes of hypo- or hyperthyroidism. Smoking is a significant risk factor for orbitopathy relapse. Physicians treating thyroid eye disease should be aware of atypical clinical presentations in order for early satisfactory treatment. An interdisciplinary approach including ophthalmologists, endocrinologists and oto-rhino-laryngologists is necessary for optimal management.

Endoscopic Endonasal Optic Nerve Decompression for Fibrous Dysplasia

PubMed Central

DeKlotz, Timothy R.; Stefko, S. Tonya; Fernandez-Miranda, Juan C.; Gardner, Paul A.; Snyderman, Carl H.; Wang, Eric W.

2016-01-01

Objective To evaluate visual outcomes and potential complications for optic nerve decompression using an endoscopic endonasal approach (EEA) for fibrous dysplasia. Design Retrospective chart review of patients with fibrous dysplasia causing extrinsic compression of the canalicular segment of the optic nerve that underwent an endoscopic endonasal optic nerve decompression at the University of Pittsburgh Medical Center from 2010 to 2013. Main Outcome Measures The primary outcome measure assessed was best-corrected visual acuity (BCVA) with secondary outcomes, including visual field testing, color vision, and complications associated with the intervention. Results A total of four patients and five optic nerves were decompressed via an EEA. All patients were symptomatic preoperatively and had objective findings compatible with compressive optic neuropathy: decreased visual acuity was noted preoperatively in three patients while the remaining patient demonstrated an afferent pupillary defect. BCVA improved in all patients postoperatively. No major complications were identified. Conclusion EEA for optic nerve decompression appears to be a safe and effective treatment for patients with compressive optic neuropathy secondary to fibrous dysplasia. Further studies are required to identify selection criteria for an open versus an endoscopic approach. PMID:28180039

Phrenic Nerve Palsy Secondary to Parsonage-Turner Syndrome: A Diagnosis Commonly Overlooked.

PubMed

McEnery, Tom; Walsh, Ronan; Burke, Conor; McGowan, Aisling; Faul, John; Cormican, Liam

2017-04-01

Neuralgic Amyotrophy (NA) or Parsonage-Turner syndrome is an idiopathic neuropathy commonly affecting the brachial plexus. Associated phrenic nerve involvement, though recognised, is thought to be very rare. We present a case series of four patients (all male, mean age 53) presenting with dyspnoea preceded by severe self-limiting upper limb and shoulder pain, with an elevated hemi-diaphragm on clinical examination and chest X-ray. Neurological examination of the upper limb at the time of presentation was normal. Diaphragmatic fluoroscopy confirmed unilateral diaphragmatic paralysis. Pulmonary function testing demonstrated characteristic reduction in forced vital capacity between supine and sitting position (mean 50%, range 42-65% predicted, mean change 23%, range 22-46%), reduced maximal inspiratory pressures (mean 61%, range 43-86% predicted), reduced sniff nasal inspiratory pressure (mean 88.25, range 66-109 cm H 2 O) and preserved maximal expiratory pressure (mean 107%, range 83-130% predicted). Phrenic nerve conduction studies confirmed phrenic nerve palsy. All patients were managed conservatively. Follow-up ranged from 6 months to 3 years. Symptoms and lung function variables normalised in three patients and improved significantly in the fourth. The classic history of severe ipsilateral shoulder and upper limb neuromuscular pain should be elicited and thus NA considered in the differential for a unilateral diaphragmatic paralysis, even in the absence of neurological signs. Parsonage-Turner syndrome is likely to represent a significantly under-diagnosed aetiology of phrenic nerve palsy. Conservative management as opposed to surgical intervention is advocated as most patients demonstrate gradual resolution over time in this case series.

Facial nerve activity disrupts psychomotor rhythms in the forehead microvasculature.

PubMed

Drummond, Peter D; O'Brien, Geraldine

2011-10-28

Forehead blood flow was monitored in seven participants with a unilateral facial nerve lesion during relaxation, respiratory biofeedback and a sad documentary. Vascular waves at 0.1Hz strengthened during respiratory biofeedback, in tune with breathing cycles that also averaged 0.1Hz. In addition, a psychomotor rhythm at 0.15Hz was more prominent in vascular waveforms on the denervated than intact side of the forehead, both before and during relaxation and the sad documentary. These findings suggest that parasympathetic activity in the facial nerve interferes with the psychomotor rhythm in the forehead microvasculature. Copyright © 2011 Elsevier B.V. All rights reserved.

Visual abnormalities associated with enhanced optic nerve myelination.

PubMed

Yu, Minzhong; Narayanan, S Priyadarshini; Wang, Feng; Morse, Emily; Macklin, Wendy B; Peachey, Neal S

2011-02-16

Expression of the constitutively active serine/threonine kinase Akt in oligodendrocytes results in enhanced myelination in the CNS. Here, we have examined the effects of this Akt overexpression on optic nerve structure and on optic nerve function, assessed using the visual evoked potential (VEP). Transgenic mice have been generated with the Plp promoter driving expression of a modified form of Akt, in which aspartic acids are substituted for Thr308 and Ser473. These Plp-Akt-DD (Akt-DD) mice, and littermate controls, were studied at different ages. Optic nerves were examined anatomically at 2 and 6 months of age. At 2 months of age, optic nerves were substantially thicker in Akt-DD mice, reflecting an increase in myelination of optic nerve axons. By electron microscopy, myelin thickness was increased in Akt-DD optic nerve, with extended paranodal domains having excess paranodal loops, and the density of nodes of Ranvier was reduced, relative to control mice. We recorded VEPs in response to strobe flash ganzfeld stimuli presented after overnight dark- and light-adapted conditions at ages ranging from 1 to 10 months. It was possible to record a clear VEP from Akt-DD mice at all ages examined. At 1 month of age, VEP implicit times were somewhat shorter in Akt-DD transgenic mice than in control animals. Beyond 6months of age, VEP latencies were consistently delayed in Akt-DD transgenic mice. These abnormalities did not reflect an alteration in retinal function as there were no significant differences between ERGs obtained from control or Akt-DD transgenic mice. In young mice, the somewhat faster responses may reflect improved transmission due to increased myelination of optic nerve axons. In older mice, where the Akt-DD optic nerve is markedly thicker than control, it is remarkable that optic nerves continue to function. Copyright © 2010 Elsevier B.V. All rights reserved.

Optic nerve involvement in childhood onset systemic lupus erythematosus: Three cases and a review of the literature.

PubMed

Suri, D; Abujam, B; Gupta, A; Rawat, A; Saikia, B; Walker Minz, R; Gupta, V; Bansal, R; Kaushik, S; Singh, S

2016-01-01

The ocular system can be affected in systemic lupus erythematosus (SLE) in one third of patients. However, optic nerve involvement is relatively uncommon, but is more so in pediatric SLE patients, where it can occur in 1% of cases. We report three children with SLE who presented with optic nerve involvement. Two children had optic neuritis, with optic neuritis being the first manifestation in one child. The third child had ischaemic optic neuropathy secondary to antiphospholipid syndrome. A careful work up for SLE should be performed in every child with optic nerve disease. Prompt diagnosis and early treatment results in a better prognosis. © The Author(s) 2015.

Near-infrared signals associated with electrical stimulation of peripheral nerves

NASA Astrophysics Data System (ADS)

Fantini, Sergio; Chen, Debbie K.; Martin, Jeffrey M.; Sassaroli, Angelo; Bergethon, Peter R.

2009-02-01

We report our studies on the optical signals measured non-invasively on electrically stimulated peripheral nerves. The stimulation consists of the delivery of 0.1 ms current pulses, below the threshold for triggering any visible motion, to a peripheral nerve in human subjects (we have studied the sural nerve and the median nerve). In response to electrical stimulation, we observe an optical signal that peaks at about 100 ms post-stimulus, on a much longer time scale than the few milliseconds duration of the electrical response, or sensory nerve action potential (SNAP). While the 100 ms optical signal we measured is not a direct optical signature of neural activation, it is nevertheless indicative of a mediated response to neural activation. We argue that this may provide information useful for understanding the origin of the fast optical signal (also on a 100 ms time scale) that has been measured non-invasively in the brain in response to cerebral activation. Furthermore, the optical response to peripheral nerve activation may be developed into a diagnostic tool for peripheral neuropathies, as suggested by the delayed optical signals (average peak time: 230 ms) measured in patients with diabetic neuropathy with respect to normal subjects (average peak time: 160 ms).

Antibodies to ependymin block the sharpening of the regenerating retinotectal projection in goldfish.

PubMed

Schmidt, J T; Shashoua, V E

1988-04-19

The regenerating optic nerve of goldfish first reestablishes a rough retinotopic map on the tectum, then goes through an activity dependent refinement that appears to involve the elimination of inappropriate branches from early regenerated arbors. Retinotopically appropriate branches and synapses may be stabilized because the normally correlated firing of neighboring ganglion cells could cause summation of their postsynaptic responses, making them more effective. Thus, refinement of the map may be similar in several ways to associative learning. In this study, we therefore tested whether ependymin, a major protein component of the extracellular fluid that has been implicated in synaptic changes thought to be associated with learning a simple task in goldfish, may also be involved in refinement of the retinotopic map. Goldfish that had undergone unilateral optic nerve crush received intraventricular infusion of antiependymin IgG or of control IgG's beginning at 21 days postcrush. Tectal recordings from these fish at 39-56 days postcrush showed that the projection had failed to sharpen, much as in the fish with activity blocked or synchronized; the average size of the multiunit receptive fields was 31 degrees vs 11 degrees normally. The field potentials elicited from these tecta by optic nerve shock were not significantly smaller than in controls, suggesting normal levels of synaptogenesis. Control projections, identically treated but infused with either unrelated IgG or Ringer's alone regenerated normally, giving multiunit receptive fields of 12 degrees. Intact (non-regenerating) projections of the experimental fish were not rendered abnormal by the IgG treatment. Histology showed the retinas and tecta of the infused fish to be normal in appearance. The results show a specific block of sharpening by antiependymin IgG. The ependymal glia of the tectum stain positively for ependymin in normal fish, particularly the cell bodies in the ependymal layer. The tectum, particularly the ependymal layer, stains more intensely during regeneration, which appears to trigger increased synthesis of ependymins in the ependymal glia. This increase and the block of sharpening by specific antibodies to ependymin suggest a possible role for ependymin in activity dependent synaptic stabilization, possibly through its polymerization when calcium is focally depleted at active synapses.

Tumors Presenting as Multiple Cranial Nerve Palsies

PubMed Central

Kumar, Kishore; Ahmed, Rafeeq; Bajantri, Bharat; Singh, Amandeep; Abbas, Hafsa; Dejesus, Eddy; Khan, Rana Raheel; Niazi, Masooma; Chilimuri, Sridhar

2017-01-01

Cranial nerve palsy could be one of the presenting features of underlying benign or malignant tumors of the head and neck. The tumor can involve the cranial nerves by local compression, direct infiltration or by paraneoplastic process. Cranial nerve involvement depends on the anatomical course of the cranial nerve and the site of the tumor. Patients may present with single or multiple cranial nerve palsies. Multiple cranial nerve involvement could be sequential or discrete, unilateral or bilateral, painless or painful. The presentation could be acute, subacute or recurrent. Anatomic localization is the first step in the evaluation of these patients. The lesion could be in the brain stem, meninges, base of skull, extracranial or systemic disease itself. We present 3 cases of underlying neoplasms presenting as cranial nerve palsies: a case of glomus tumor presenting as cochlear, glossopharyngeal, vagus and hypoglossal nerve palsies, clivus tumor presenting as abducens nerve palsy, and diffuse large B-cell lymphoma presenting as oculomotor, trochlear, trigeminal and abducens nerve palsies due to paraneoplastic involvement. History and physical examination, imaging, autoantibodies and biopsy if feasible are useful for the diagnosis. Management outcomes depend on the treatment of the underlying tumor. PMID:28553221

Radiation optic neuropathy after megavoltage external-beam irradiation: Analysis of time-dose factors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parsons, J.T.; Bova, F.J.; Million, R.R.

1994-11-15

To investigate the risk of radiation-induced optic neuropathy according to total radiotherapy dose and fraction size, based on both retrospective and prospectively collected data. Between October 1964 and May 1989, 215 optic nerves in 131 patients received fractionated external-beam irradiation during the treatment of primary extracranial head and neck tumors. All patients had a minimum of 3 years of ophthalmologic follow-up (range, 3 to 21 years). The clinical end point was visual acuity of 20/100 or worse as a result of optic nerve injury. Anterior ischemic optic neuropathy developed in five nerves (at mean and median times of 32 andmore » 30 months, respectively, and a range of 2-4 years). Retrobulbar optic neuropathy developed in 12 nerves (at mean and median times of 47 and 28 months, respectively, and a range of 1-14 years). No injuries were observed in 106 optic nerves that received a total dose of <59 Gy. Among nerves that received doses of {ge} 60 Gy, the dose per fraction was more important than the total dose in producing optic neuropathy. The 15-year actuarial risk of optic compared with 47% when given in fraction sizes {ge}1.9 Gy. The data also suggest an increased risk of optic nerve injury with increasing age. As there is no effective treatment of radiation-induced optic neuropathy, efforts should be directed at its prevention by minimizing the total dose, paying attention to the dose per fraction to the nerve, and using reduced field techniques where appropriate to limit the volume of tissues that receive high-dose irradiation. 32 refs., 5 figs., 5 tabs.« less

Axonal loss from acute optic neuropathy documented by scanning laser polarimetry

PubMed Central

Meier, F M; Bernasconi, P; Stürmer, J; Caubergh, M-J; Landau, K

2002-01-01

Background/aims: Retinal nerve fibre layer analysis by scanning laser polarimetry has been shown to facilitate diagnosis of glaucoma while its role in glaucoma follow up is still unclear. A major difficulty is the slow reduction of retinal nerve fibre layer thickness in glaucomatous optic neuropathy. Eyes of patients were studied after acute retrobulbar optic nerve lesion in order to evaluate the usefulness of scanning laser polarimetry in documenting retinal nerve fibre layer loss over time. Methods: Five patients who suffered severe retrobulbar optic neuropathy have had repeated measurements of the retinal nerve fibre layer using scanning laser polarimetry at various intervals, the first examination being within 1 week of injury. Results: All eyes showed a marked decrease in peripapillary retinal nerve fibre layer thickness, which followed an exponential curve and occurred predominantly within 8 weeks of injury. Compared to a previous study using red-free photographs, scanning laser polarimetry showed retinal nerve fibre layer loss earlier in the course of descending atrophy. Conclusion: Scanning laser polarimetry is useful for early detection and documentation of retinal nerve fibre layer loss following acute injury to the retrobulbar optic nerve. It seems to be a promising tool for follow up of individual glaucoma patients. PMID:11864884

Sox10 Expression in Goldfish Retina and Optic Nerve Head in Controls and after the Application of Two Different Lesion Paradigms

PubMed Central

Parrilla, Marta; León-Lobera, Fernando; Lillo, Concepción; Arévalo, Rosario; Aijón, José; Lara, Juan Manuel; Velasco, Almudena

2016-01-01

The mammalian central nervous system (CNS) is unable to regenerate. In contrast, the CNS of fish, including the visual system, is able to regenerate after damage. Moreover, the fish visual system grows continuously throughout the life of the animal, and it is therefore an excellent model to analyze processes of myelination and re-myelination after an injury. Here we analyze Sox10+ oligodendrocytes in the goldfish retina and optic nerve in controls and after two kinds of injuries: cryolesion of the peripheral growing zone and crushing of the optic nerve. We also analyze changes in a major component of myelin, myelin basic protein (MBP), as a marker for myelinated axons. Our results show that Sox10+ oligodendrocytes are located in the retinal nerve fiber layer and along the whole length of the optic nerve. MBP was found to occupy a similar location, although its loose appearance in the retina differed from the highly organized MBP+ axon bundles in the optic nerve. After optic nerve crushing, the number of Sox10+ cells decreased in the crushed area and in the optic nerve head. Consistent with this, myelination was highly reduced in both areas. In contrast, after cryolesion we did not find changes in the Sox10+ population, although we did detect some MBP- degenerating areas. We show that these modifications in Sox10+ oligodendrocytes are consistent with their role in oligodendrocyte identity, maintenance and survival, and we propose the optic nerve head as an excellent area for research aimed at better understanding of de- and remyelination processes. PMID:27149509

Different effects of astrocytes and Schwann cells on regenerating retinal axons.

PubMed

Campbell, Gregor; Kitching, Juliet; Anderson, Patrick N; Lieberman, A Robert

2003-11-14

Following a crush injury of the optic nerve in adult rats, the axons of retinal ganglion cells, stimulated to regenerate by a lens injury and growing within the optic nerve, are associated predominantly with astrocytes: they remain of small diameter (0.1-0.5 microm) and unmyelinated for > or = 2 months after the operation. In contrast, when the optic nerve is cut and a segment of a peripheral nerve is grafted to the ocular stump of the optic nerve, the regenerating retinal axons are associated predominantly with Schwann cells: they are of larger diameter than in the previous experiment and include unmyelinated axons (0.2-2.5 microm) and myelinated axons (mean diameter 2.3 microm). Thus, the grafted peripheral nerve, and presumably its Schwann cells, stimulate enlargement of the regenerating retinal axons leading to partial myelination, whereas the injured optic nerve itself, and presumably its astrocytes, does not. The result points to a marked difference of peripheral (Schwann cells) and central (astrocytes) glia in their effect on regenerating retinal axons.

Electrophysiological abnormalities associated with extensive myelinated retinal nerve fibers.

PubMed

Tay, Su Ann; Sanjay, Srinivasan

2012-07-01

An observational case report of electrophysiological abnormalities in a patient with anisomyopic amblyopia as a result of unilateral extensive myelinated retinal nerve fibers (MNFs) is illustrated. The electrophysiological readings revealed an abnormal pattern electroretinogram (PERG) but normal full-field electroretinogram readings in the affected eye. The visual-evoked potential was also undetectable in that eye. Our findings suggest that extensive MNFs can be associated with electrophysiological abnormalities, in particular the PERG, which can aid in diagnosing the cause of impaired vision when associated with amblyopia.

Abnormalities of gaze in cerebrovascular disease.

PubMed

Pedersen, R A; Troost, B T

1981-01-01

Disorders of ocular motility may occur after injury at several levels of the neuraxis. Unilateral supranuclear disorders of gaze tend to be transient; bilateral disorders more enduring. Nuclear disorders of gaze also tend to be enduring and are frequently present in association with long tract signs and cranial nerve palsies on opposite sides of the body. Nystagmus is a reliable sign of posterior fossa or peripheral eight nerve pathology. Familiarity with these concepts may help the clinician answer questions regarding localization and prognosis.

Astrocytes as gate-keepers in optic nerve regeneration--a mini-review.

PubMed

García, Dana M; Koke, Joseph R

2009-02-01

Animals that develop without extra-embryonic membranes (anamniotes--fish, amphibians) have impressive regenerative capacity, even to the extent of replacing entire limbs. In contrast, animals that develop within extra-embryonic membranes (amniotes--reptiles, birds, mammals) have limited capacity for regeneration as adults, particularly in the central nervous system (CNS). Much is known about the process of nerve development in fish and mammals and about regeneration after lesions in the CNS in fish and mammals. Because the retina of the eye and optic nerve are functionally part of the brain and are accessible in fish, frogs, and mice, optic nerve lesion and regeneration (ONR) has been extensively used as a model system for study of CNS nerve regeneration. When the optic nerve of a mouse is severed, the axons leading into the brain degenerate. Initially, the cut end of the axons on the proximal, eye-side of the injury sprout neurites which begin to grow into the lesion. Simultaneously, astrocytes of the optic nerve become activated to initiate wound repair as a first step in reestablishing the structural integrity of the optic nerve. This activation appears to initiate a cascade of molecular signals resulting in apoptotic cell death of the retinal ganglion cells axons of which make up the neural component of the optic nerve; regeneration fails and the injury is permanent. Evidence specifically implicating astrocytes comes from studies showing selective poisoning of astrocytes at the optic nerve lesion, along with activation of a gene whose product blocks apoptosis in retinal ganglion cells, creates conditions favorable to neurites sprouting from the cut proximal stump, growing through the lesion and into the distal portion of the injured nerve, eventually reaching appropriate targets in the brain. In anamniotes, astrocytes ostensibly present no such obstacle since optic nerve regeneration occurs without intervention; however, no systematic study of glial involvement has been done. In fish, vigorously growing neurites sprout from the cut axons and within a few days begin to re-enervate the brain. This review offers a new perspective on the role of glia, particularly astrocytes, as "gate-keepers;" i.e., as being permissive or inhibitory, by comparison between fish and mammals of glial function during ONR.

Masseteric nerve for reanimation of the smile in short-term facial paralysis.

PubMed

Hontanilla, Bernardo; Marre, Diego; Cabello, Alvaro

2014-02-01

Our aim was to describe our experience with the masseteric nerve in the reanimation of short term facial paralysis. We present our outcomes using a quantitative measurement system and discuss its advantages and disadvantages. Between 2000 and 2012, 23 patients had their facial paralysis reanimated by masseteric-facial coaptation. All patients are presented with complete unilateral paralysis. Their background, the aetiology of the paralysis, and the surgical details were recorded. A retrospective study of movement analysis was made using an automatic optical system (Facial Clima). Commissural excursion and commissural contraction velocity were also recorded. The mean age at reanimation was 43(8) years. The aetiology of the facial paralysis included acoustic neurinoma, fracture of the skull base, schwannoma of the facial nerve, resection of a cholesteatoma, and varicella zoster infection. The mean time duration of facial paralysis was 16(5) months. Follow-up was more than 2 years in all patients except 1 in whom it was 12 months. The mean duration to recovery of tone (as reported by the patient) was 67(11) days. Postoperative commissural excursion was 8(4)mm for the reanimated side and 8(3)mm for the healthy side (p=0.4). Likewise, commissural contraction velocity was 38(10)mm/s for the reanimated side and 43(12)mm/s for the healthy side (p=0.23). Mean percentage of recovery was 92(5)mm for commissural excursion and 79(15)mm/s for commissural contraction velocity. Masseteric nerve transposition is a reliable and reproducible option for the reanimation of short term facial paralysis with reduced donor site morbidity and good symmetry with the opposite healthy side. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Evolution of optic nerve photography for glaucoma screening: a review.

PubMed

Myers, Jonathan S; Fudemberg, Scott J; Lee, Daniel

2018-03-01

Visual evaluation of the optic nerve has been one of the earliest and most widely used methods to evaluate patients for glaucoma. Photography has proven very useful for documentation of the nerve's appearance at a given time, allowing more detailed scrutiny then, and later comparison for change. Photography serves as the basis for real-time or non-simultaneous review in telemedicine and screening events allowing fundus and optic nerve evaluation by experts elsewhere. Expert evaluation of disc photographs has shown diagnostic performance similar to other methods of optic nerve evaluation for glaucoma. Newer technology has made optic nerve photography simpler, cheaper and more portable creating opportunities for broader utilization in screening in underserved populations by non-physicians. Recent investigations suggest that non-physicians or software algorithms for disc photograph evaluation have promise to allow more screening to be done with fewer experts. © 2017 Royal Australian and New Zealand College of Ophthalmologists.

High resolution ultrasound and magnetic resonance imaging of the optic nerve and the optic nerve sheath: anatomic correlation and clinical importance.

PubMed

Steinborn, M; Fiegler, J; Kraus, V; Denne, C; Hapfelmeier, A; Wurzinger, L; Hahn, H

2011-12-01

We performed a cadaver study to evaluate the accuracy of measurements of the optic nerve and the optic nerve sheath for high resolution US (HRUS) and magnetic resonance imaging (MRI). Five Thiel-fixated cadaver specimens of the optic nerve were examined with HRUS and MRI. Measurements of the optic nerve and the ONSD were performed before and after the filling of the optic nerve sheath with saline solution. Statistical analysis included the calculation of the agreement of measurements and the evaluation of the intraobserver and interobserver variation. Overall a good correlation of measurement values between HRUS and MRI can be found (mean difference: 0.02-0.97 mm). The repeatability coefficient (RC) and concordance correlation coefficient (CCC) values were good to excellent for most acquisitions (RC 0.2-1.11 mm; CCC 0.684-0.949). The highest variation of measurement values was found for transbulbar sonography (RC 0.58-1.83 mm; CCC 0.615/0.608). If decisive anatomic structures are clearly depicted and the measuring points are set correctly, there is a good correlation between HRUS and MRI measurements of the optic nerve and the ONSD even on transbulbar sonography. As most of the standard and cut-off values that have been published for ultrasound are significantly lower than the results obtained with MRI, a reevaluation of sonographic ONSD measurement with correlation to MRI is necessary. © Georg Thieme Verlag KG Stuttgart · New York.

Acquired pit of the optic nerve: a risk factor for progression of glaucoma.

PubMed

Ugurlu, S; Weitzman, M; Nduaguba, C; Caprioli, J

1998-04-01

To examine acquired pit of the optic nerve as a risk factor for progression of glaucoma. In a retrospective longitudinal study, 25 open-angle glaucoma patients with acquired pit of the optic nerve were compared with a group of 24 open-angle glaucoma patients without acquired pit of the optic nerve. The patients were matched for age, mean intraocular pressure, baseline ratio of neuroretinal rim area to disk area, visual field damage, and duration of follow-up. Serial optic disk photographs and visual fields of both groups were evaluated by three independent observers for glaucomatous progression. Of 46 acquired pits of the optic nerve in 37 eyes of 25 patients, 36 pits were located inferiorly (76%) and 11 superiorly (24%; P < .001). Progression of optic disk damage occurred in 16 patients (64%) in the group with acquired pit and in three patients (12.5%) in the group without acquired pit (P < .001). Progression of visual field loss occurred in 14 patients (56%) in the group with acquired pit and in six (25%) in the group without pit (P=.04). Bilateral acquired pit of the optic nerve was present in 12 patients (48%). Disk hemorrhages were observed more frequently in the group with acquired pit (10 eyes, 40%) compared with the group without pit (two eyes, 8%; P=.02). Among patients with glaucoma, patients with acquired pit of the optic nerve represent a subgroup who are at increased risk for progressive optic disk damage and visual field loss.

Pan-brachial plexus neuropraxia following lightning: A rare case report.

PubMed

Patnaik, Ashis; Mahapatra, Ashok Kumar; Jha, Menka

2015-01-01

Neurological complications following lightning are rare and occur in form of temporary neurological deficits of central origin. Involvement of peripheral nervous system is extremely rare and only a few cases have been described in the literature. Isolated unilateral pan-brachial plexus neuropraxia has never been reported in the literature. Steroids have long been used for treatment of neuropraxia. However, their use in lightning neural injury is unique and requires special mention. We report a rare case of lightning-induced unilateral complete flaccid paralysis along with sensory loss in a young patient. Lightning typically causes central nervous involvement in various types of motor and sensory deficit. Surprisingly, the nerve conduction study showed the involvement of peripheral nervous system involvement. Steroids were administered and there was significant improvement in neurological functions within a short span of days. Patients' functions in the affected limb were normal in one month. Our case was interesting since it is the first such case in the literature where lightning has caused such a rare instance of unilateral pan-brachial plexus lesion. Such cases when seen, raises the possibility of more common central nervous system pathology rather than peripheral involvement. However, such lesions can be purely benign forms of peripheral nerve neuropraxia, which can be managed by steroid treatment without leaving any long-term neurological deficits.

Supraorbital keyhole surgery for optic nerve decompression and dura repair.

PubMed

Chen, Yuan-Hao; Lin, Shinn-Zong; Chiang, Yung-Hsiao; Ju, Da-Tong; Liu, Ming-Ying; Chen, Guann-Juh

2004-07-01

Supraorbital keyhole surgery is a limited surgical procedure with reduced traumatic manipulation of tissue and entailing little time in the opening and closing of wounds. We utilized the approach to treat head injury patients complicated with optic nerve compression and cerebrospinal fluid leakage (CSF). Eleven cases of basal skull fracture complicated with either optic nerve compression and/or CSF leakage were surgically treated at our department from February 1995 to June 1999. Six cases had primary optic nerve compression, four had CSF leakage and one case involved both injuries. Supraorbital craniotomy was carried out using a keyhole-sized burr hole plus a small craniotomy. The size of craniotomy approximated 2 x 3 cm2. The optic nerve was decompressed via removal of the optic canal roof and anterior clinoid process with high-speed drills. The defect of dura was repaired with two pieces of tensa fascia lata that were attached on both sides of the torn dural defect with tissue glue. Seven cases with optic nerve injury included five cases of total blindness and two cases of light perception before operation. Vision improved in four cases. The CSF leakage was stopped successfully in all four cases without complication. As optic nerve compression and CSF leakage are skull base lesions, the supraorbital keyhole surgery constitutes a suitable approach. The supraorbital keyhole surgery allows for an anterior approach to the skull base. This approach also allows the treatment of both CSF leakage and optic nerve compression. Our results indicate that supraorbital keyhole operation is a safe and effective method for preserving or improving vision and attenuating CSF leakage following injury.

Anomalous optic discs in a patient with a Dandy-Walker cyst.

PubMed

Orcutt, J C; Bunt, A H

1982-03-01

A 19-month-old female infant with a Dandy-Walker cyst had anomalous optic discs, each of which appeared to divide to form an accessory optic nerve. The discs probably lie within the spectrum of anomalous discs including optic nerve aplasia and hypoplasia, megallopapillae, morning glory disc, optic disc dysplasia, and optic nerve colobomas. The association of anomalous optic discs with a Dandy-Walker cyst has not been previously recognized. The ocular and brain malformations in this patient likely occurred during the fourth to eighth week of gestation, when the retinal ganglion cell axons were penetrating the optic nerve, and the rhombic lips were enlarging in early cerebellar development. The etiology of these anomalies is not known; however, teratogens, sporadic events, and genetic disorders should be considered.

Optic nerve axons and acquired alterations in the appearance of the optic disc.

PubMed Central

Wirtschafter, J D

1983-01-01

The pathophysiologic events in optic nerve axons have recently been recognized as crucial to an understanding of clinically significant acquired alterations in the ophthalmoscopic appearance of the optic disc. Stasis and related abnormalities of axonal transport appear to explain most aspects of optic nerve head swelling, including optic disc drusen and retinal cottonwool spots. Loss of axoplasm and axonal death can be invoked to interpret optic disc pallor, thinning and narrowing of rim tissue, changes in the size and outline of the optic cup, laminar dots, atrophy of the retinal nerve fiber layer, and acquired demyelination and myelination of the retinal nerve fiber layer. It is speculated that the axons may also play a role in the mechanical support of the lamina cribrosa in resisting the pressure gradient across the pars scleralis of the optic nerve head. Axons and their associated glial cells may be involved in those cases where "reversibility" of cupping of the optic disc has been reported. The structure, physiology, and experimental pathologic findings of the optic nerve head have been reviewed. Many aspects concerning the final anatomic appearance of the optic nerve head have been explained. However, many questions remain concerning the intermediate mechanisms by which increased intracranial pressure retards the various components of axonal transport in papilledema and by which increased IOP causes axonal loss in glaucoma. Investigation of the molecular biology of axonal constituents and their responses to abnormalities in their physical and chemical milieu could extend our understanding of the events that result from mechanical compression and local ischemia. Moreover, we have identified a need to further explore the role of axons in the pathophysiology of optic disc cupping. Images FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 11 FIGURE 12 FIGURE 13 PMID:6203209

A Multidisciplinary Approach to Educating Preschool Children with Optic Nerve Hypoplasia and Septo-Optic Nerve Dysplasia.

ERIC Educational Resources Information Center

Bahar, Cheryl; Brody, Jill; McCann, Mary Ellen; Mendiola, Rosalinda; Slott, Gayle

2003-01-01

This article discusses the observations and experiences of a multidisciplinary team at the Blind Childrens Center in Los Angeles, which works specifically with children from birth to 5 years of age who have been diagnosed with optic nerve hypoplasia and may have septo-optic displasia. Strategies for educational interventions are explained.…

Intracanalicular Optic Nerve Swelling and Signal Change in Fulminant Untreated Idiopathic Intracranial Hypertension.

PubMed

Moodley, Anand A; Dlwati, Mahlubonke S; Durand, Miranda

2017-04-01

The role of the optic canal in the pathogenesis of papilloedema has been under scrutiny recently. Whether a larger canal precedes more severe papilloedema or is the result of bone remodelling from chronically raised pressure across a pressure gradient is not clear. The authors present the magnetic resonance imaging findings of a 29-year-old female with fulminant and untreated idiopathic intracranial hypertension. Imaging showed focal expansion and intrinsic signal changes of the intracanalicular optic nerve. The authors discuss the possibility of either fluid accumulation within the optic nerves from a water hammer effect across blocked optic canals resulting from the steep pressure gradient or opticomalacia (optic nerve softening) from chronic ischaemia.

Cutaneous Surgical Denervation: A Method for Testing the Requirement for Nerves in Mouse Models of Skin Disease.

PubMed

Peterson, Shelby C; Brownell, Isaac; Wong, Sunny Y

2016-06-26

Cutaneous somatosensory nerves function to detect diverse stimuli that act upon the skin. In addition to their established sensory roles, recent studies have suggested that nerves may also modulate skin disorders including atopic dermatitis, psoriasis and cancer. Here, we describe protocols for testing the requirement for nerves in maintaining a cutaneous mechanosensory organ, the touch dome (TD). Specifically, we discuss methods for genetically labeling, harvesting and visualizing TDs by whole-mount staining, and for performing unilateral surgical denervation on mouse dorsal back skin. Together, these approaches can be used to directly compare TD morphology and gene expression in denervated as well as sham-operated skin from the same animal. These methods can also be readily adapted to examine the requirement for nerves in mouse models of skin pathology. Finally, the ability to repeatedly sample the skin provides an opportunity to monitor disease progression at different stages and times after initiation.

Imaging of the optic nerve and retinal nerve fiber layer: an essential part of glaucoma diagnosis and monitoring.

PubMed

Kotowski, Jacek; Wollstein, Gadi; Ishikawa, Hiroshi; Schuman, Joel S

2014-01-01

Because glaucomatous damage is irreversible early detection of structural changes in the optic nerve head and retinal nerve fiber layer is imperative for timely diagnosis of glaucoma and monitoring of its progression. Significant improvements in ocular imaging have been made in recent years. Imaging techniques such as optical coherence tomography, scanning laser polarimetry and confocal scanning laser ophthalmoscopy rely on different properties of light to provide objective structural assessment of the optic nerve head, retinal nerve fiber layer and macula. In this review, we discuss the capabilities of these imaging modalities pertinent for diagnosis of glaucoma and detection of progressive glaucomatous damage and provide a review of the current knowledge on the clinical performance of these technologies. Copyright © 2014 Elsevier Inc. All rights reserved.

PATHOGENESIS OF OPTIC DISC EDEMA IN RAISED INTRACRANIAL PRESSURE

PubMed Central

Hayreh, Sohan Singh

2015-01-01

Optic disc edema in raised intracranial pressure was first described in 1853. Ever since, there has been a plethora of controversial hypotheses to explain its pathogenesis. I have explored the subject comprehensively by doing basic, experimental and clinical studies. My objective was to investigate the fundamentals of the subject, to test the validity of the previous theories, and finally, based on all these studies, to find a logical explanation for the pathogenesis. My studies included the following issues pertinent to the pathogenesis of optic disc edema in raised intracranial pressure: the anatomy and blood supply of the optic nerve, the roles of the sheath of the optic nerve, of the centripetal flow of fluids along the optic nerve, of compression of the central retinal vein, and of acute intracranial hypertension and its associated effects. I found that, contrary to some previous claims, an acute rise of intracranial pressure was not quickly followed by production of optic disc edema. Then, in rhesus monkeys, I produced experimentally chronic intracranial hypertension by slowly increasing in size space-occupying lesions, in different parts of the brain. Those produced raised cerebrospinal fluid pressure (CSFP) and optic disc edema, identical to those seen in patients with elevated CSFP. Having achieved that, I investigated various aspects of optic disc edema by ophthalmoscopy, stereoscopic color fundus photography and fluorescein fundus angiography, and light microscopic, electron microscopic, horseradish peroxidase and axoplasmic transport studies, and evaluated the effect of opening the sheath of the optic nerve on the optic disc edema. This latter study showed that opening the sheath resulted in resolution of optic disc edema on the side of the sheath fenestration, in spite of high intracranial CSFP, proving that a rise of CSFP in the sheath was the essential pre-requisite for the development of optic disc edema. I also investigated optic disc edema with raised CSFP in patients, by evaluating optic disc and fundus changes by stereoscopic fundus photography and fluorescein fundus angiography. Based on the combined information from all the studies discussed above, it is clear that the pathogenesis of optic disc edema in raised intracranial pressure is a mechanical phenomenon. It is primarily due to a rise of CSFP in the optic nerve sheath, which produces axoplasmic flow stasis in the optic nerve fibers in the surface nerve fiber layer and prelaminar region of the optic nerve head. Axoplasmic flow stasis then results in swelling of the nerve fibers, and consequently of the optic disc. Swelling of the nerve fibers and of the optic disc secondarily compresses the fine, low-pressure venules in that region, resulting in venous stasis and fluid leakage; that leads to the accumulation of extracellular fluid. Contrary to the previous theories, the various vascular changes seen in optic disc edema are secondary and not primary. Thus, optic disc edema in raised CSFP is due to a combination of swollen nerve fibers and the accumulation of extracellular fluid. My studies also provided information about the pathogeneses of visual disturbances in raised intracranial pressure. PMID:26453995

Pathogenesis of optic disc edema in raised intracranial pressure.

PubMed

Hayreh, Sohan Singh

2016-01-01

Optic disc edema in raised intracranial pressure was first described in 1853. Ever since, there has been a plethora of controversial hypotheses to explain its pathogenesis. I have explored the subject comprehensively by doing basic, experimental and clinical studies. My objective was to investigate the fundamentals of the subject, to test the validity of the previous theories, and finally, based on all these studies, to find a logical explanation for the pathogenesis. My studies included the following issues pertinent to the pathogenesis of optic disc edema in raised intracranial pressure: the anatomy and blood supply of the optic nerve, the roles of the sheath of the optic nerve, of the centripetal flow of fluids along the optic nerve, of compression of the central retinal vein, and of acute intracranial hypertension and its associated effects. I found that, contrary to some previous claims, an acute rise of intracranial pressure was not quickly followed by production of optic disc edema. Then, in rhesus monkeys, I produced experimentally chronic intracranial hypertension by slowly increasing in size space-occupying lesions, in different parts of the brain. Those produced raised cerebrospinal fluid pressure (CSFP) and optic disc edema, identical to those seen in patients with elevated CSFP. Having achieved that, I investigated various aspects of optic disc edema by ophthalmoscopy, stereoscopic color fundus photography and fluorescein fundus angiography, and light microscopic, electron microscopic, horseradish peroxidase and axoplasmic transport studies, and evaluated the effect of opening the sheath of the optic nerve on the optic disc edema. This latter study showed that opening the sheath resulted in resolution of optic disc edema on the side of the sheath fenestration, in spite of high intracranial CSFP, proving that a rise of CSFP in the sheath was the essential pre-requisite for the development of optic disc edema. I also investigated optic disc edema with raised CSFP in patients, by evaluating optic disc and fundus changes by stereoscopic fundus photography and fluorescein fundus angiography. Based on the combined information from all the studies discussed above, it is clear that the pathogenesis of optic disc edema in raised intracranial pressure is a mechanical phenomenon. It is primarily due to a rise of CSFP in the optic nerve sheath, which produces axoplasmic flow stasis in the optic nerve fibers in the surface nerve fiber layer and prelaminar region of the optic nerve head. Axoplasmic flow stasis then results in swelling of the nerve fibers, and consequently of the optic disc. Swelling of the nerve fibers and of the optic disc secondarily compresses the fine, low-pressure venules in that region, resulting in venous stasis and fluid leakage; that leads to the accumulation of extracellular fluid. Contrary to the previous theories, the various vascular changes seen in optic disc edema are secondary and not primary. Thus, optic disc edema in raised CSFP is due to a combination of swollen nerve fibers and the accumulation of extracellular fluid. My studies also provided information about the pathogeneses of visual disturbances in raised intracranial pressure. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Pay attention to the secondary optic neuropathy and the safe appropriate applications of optic neuroprotection].

PubMed

Zhong, Y

2016-12-11

Secondary optic neuropathy of optic nerve abnormalities is the leading cause of persistent visual impairment. Previous ocular neuroprotection studies have proved that the nerve growth factor and other agents are of significant in the preservation of optic nerve axon and retinal ganglion cells. However, finding novel safe and effective approach as well as the appropriate applications of optic neuroprotection should be highly emphasized and would be very helpful in the treatment of optic neuropathy. (Chin J Ophthalmol, 2016, 52: 881 - 884) .

Pulsed laser versus electrical energy for peripheral nerve stimulation

PubMed Central

Wells, Jonathon; Konrad, Peter; Kao, Chris; Jansen, E. Duco; Mahadevan-Jansen, Anita

2010-01-01

Transient optical neural stimulation has previously been shown to elicit highly controlled, artifact-free potentials within the nervous system in a non-contact fashion without resulting in damage to tissue. This paper presents the physiologic validity of elicited nerve and muscle potentials from pulsed laser induced stimulation of the peripheral nerve in a comparative study with the standard method of electrically evoked potentials. Herein, the fundamental physical properties underlying the two techniques are contrasted. Key laser parameters for efficient optical stimulation of the peripheral nerve are detailed. Strength response curves are shown to be linear for each stimulation modality, although fewer axons can be recruited with optically evoked potentials. Results compare the relative transient energy requirements for stimulation using each technique and demonstrate that optical methods can selectively excite functional nerve stimulation. Adjacent stimulation and recording of compound nerve potentials in their entirety from optical and electrical stimulation are presented, with optical responses shown to be free of any stimulation artifact. Thus, use of a pulsed laser exhibits some advantages when compared to standard electrical means for excitation of muscle potentials in the peripheral nerve in the research domain and possibly for clinical diagnostics in the future. PMID:17537515

A polarization measurement method for the quantification of retardation in optic nerve fiber layer

NASA Astrophysics Data System (ADS)

Fukuma, Yasufumi; Okazaki, Yoshio; Shioiri, Takashi; Iida, Yukio; Kikuta, Hisao; Ohnuma, Kazuhiko

2008-02-01

The thickness measurement of the optic nerve fiber layer is one of the most important evaluations for carrying out glaucoma diagnosis. Because the optic nerve fiber layer has birefringence, the thickness can be measured by illuminating eye optics with circular polarized light and analyzing the elliptical rate of the detected polarized light reflected from the optic nerve fiber layer. In this method, the scattering light from the background and the retardation caused by the cornea disturbs the precise measurement. If the Stokes vector expressing the whole state of polarization can be detected, we can eliminate numerically the influence of the background scattering and of the retardation caused by the cornea. Because the retardation process of the eye optics can be represented by a numerical equation using the retardation matrix of each component and also the nonpolarized background scattering light, it can be calculated by using the Stokes vector. We applied a polarization analysis system that can detect the Stokes vector onto the fundus camera. The polarization analysis system is constructed with a CCD area image sensor, a linear polarizing plate, a micro phase plate array, and a circularly polarized light illumination unit. With this simply constructed system, we can calculate the retardation caused only by the optic nerve fiber layer and it can predict the thickness of the optic nerve fiber layer. We report the method and the results graphically showing the retardation of the optic nerve fiber layer without the retardation of the cornea.

Circadian locomotor rhythms in the cricket, Gryllodes sigillatus. II. Interactions between bilaterally paired circadian pacemakers.

PubMed

Ushirogawa, H; Abe, Y; Tomioka, K

1997-10-01

The optic lobe is essential for circadian locomotor rhythms in the cricket, Gryllodes sigillatus. We examined potential interactions between the bilaterally paired optic lobes in circadian rhythm generation. When one optic lobe was removed, the free-running period of the locomotor rhythm slightly but significantly lengthened. When exposed to light-dark cycles (LD) with 26 hr period, intact and sham operated animals were clearly entrained to the light cycle, but a large number of animals receiving unilateral optic nerve severance showed rhythm dissociation. In the dissociation, two rhythmic components appeared; one was readily entrained to the given LD and the other free-ran with a period shorter than 24 hr, and activity was expressed only when they were inphase. The period of the free-running component was significantly longer than that of the animals with a single blinded pacemaker kept in LD13:13, suggesting that the pacemaker on the intact side had some influence on the blinded pacemaker even in the dissociated state. The ratio of animals with rhythm dissociation was greater with the lower light intensity of the LD. The results suggest that the bilaterally distributed pacemakers are only weakly coupled to one another but strongly suppress the activity driven by the partner pacemaker during their subjective day. The strong suppression of activity would be advantageous to keep a stable nocturnality for this cricket living indoors.

[Influence of trigeminal nerve lesion on facial growth: study of two cases of Goldenhar syndrome].

PubMed

Darris, Pierre; Treil, Jacques; Marchal-Sixou, Christine; Baron, Pascal

2015-06-01

This cases report confirms the hypothesis that embryonic and maxillofacial growth are influenced by the peripheral nervous system, including the trigeminal nerve (V). So, it's interesting to use the stigma of the trigeminal nerve as landmarks to analyze the maxillofacial volume and understand its growth. The aim of this study is to evaluate the validity of the three-dimensional cephalometric analysis of Treil based on trigeminal landmarks. The first case is a caucasian female child with Goldenhar syndrome. The second case is a caucasian male adult affected by the same syndrome. In both cases, brain MRI showed an unilateral trigeminal nerve lesion, ipsilateral to the facial dysmorphia. The results of this radiological study tend to prove the primary role of the trigeminal nerve in craniofacial growth. These cases demonstrate the validity of the theory of Moss. They are one of anatomo-functional justifications of the three-dimensional cephalometric biometry of Treil based on trigeminal nerve landmarks. © EDP Sciences, SFODF, 2015.

Complete dislocation of the ulnar nerve at the elbow: a protective effect against neuropathy?

PubMed

Leis, A Arturo; Smith, Benn E; Kosiorek, Heidi E; Omejec, Gregor; Podnar, Simon

2017-08-01

Recurrent complete ulnar nerve dislocation has been perceived as a risk factor for development of ulnar neuropathy at the elbow (UNE). However, the role of dislocation in the pathogenesis of UNE remains uncertain. We studied 133 patients with complete ulnar nerve dislocation to determine whether this condition is a risk factor for UNE. In all, the nerve was palpated as it rolled over the medial epicondyle during elbow flexion. Of 56 elbows with unilateral dislocation, UNE localized contralaterally in 17 elbows (30.4%) and ipsilaterally in 10 elbows (17.9%). Of 154 elbows with bilateral dislocation, 26 had UNE (16.9%). Complete dislocation decreased the odds of having UNE by 44% (odds ratio = 0.475; P =  0.028), and was associated with less severe UNE (P = 0.045). UNE occurs less frequently and is less severe on the side of complete dislocation. Complete dislocation may have a protective effect on the ulnar nerve. Muscle Nerve 56: 242-246, 2017. © 2016 Wiley Periodicals, Inc.

Blindness associated with nasal/paranasal lymphoma in a stallion.

PubMed

Sano, Yuto; Okamoto, Minoru; Ootsuka, Youhei; Matsuda, Kazuya; Yusa, Shigeki; Taniyama, Hiroyuki

2017-03-23

A 29-year-old stallion presented with bilateral blindness following the chronic purulent nasal drainage. The mass occupied the right caudal nasal cavity and right paranasal sinuses including maxillary, palatine and sphenoidal sinuses, and the right-side turbinal and paranasal septal bones, and cribriform plate of ethmoid bone were destructively replaced by the mass growth. The right optic nerve was invaded and involved by the mass, and the left optic nerve and optic chiasm were compressed by the mass which was extended and invaded the skull base. Histologically, the optic nerves and optic chiasm were degenerated, and the mass was diagnosed as lymphoma which was morphologically and immunohistochemically classified as a diffuse large B-cell lymphoma. Based on these findings, the cause of the blindness in the stallion was concluded to be due to the degeneration of the optic nerves and chiasm associated with lymphoma occurring in the nasal and paranasal cavities. To the best of our knowledge, this is the first report of the equine blindness with optic nerve degeneration accompanied by lymphoma.

Inflammatory Papillitis in Uveitis: Response to Treatment and Use of Optic Nerve Optical Coherence Tomography for Monitoring.

PubMed

Cho, Heeyoon; Pillai, Parvathy; Nicholson, Laura; Sobrin, Lucia

2016-01-01

To describe the clinical course of uveitis-associated inflammatory papillitis and evaluate the utility and reproducibility of optic nerve spectral domain optical coherence tomography (SD-OCT). Data on 22 eyes of 14 patients with uveitis-related papillitis and optic nerve imaging were reviewed. SD-OCT measure reproducibility was determined and parameters were compared in active vs. inactive uveitis. Papillitis resolution lagged behind uveitis resolution in three patients. For SD-OCT measures, the intraclass correlation coefficients were 99.1-100% and 86.9-100% for intraobserver and interobserver reproducibility, respectively. All SD-OCT optic nerve measures except inferior and nasal peripapillary retinal thicknesses were significantly higher in active vs. inactive uveitis after correction for multiple hypotheses testing. Mean optic nerve central thickness decreased from 545.1 to 362.9 µm (p = 0.01). Resolution of inflammatory papillitis can lag behind resolution of uveitis. SD-OCT assessment of papillitis is reproducible and correlates with presence vs. resolution of uveitis.

Age-related posterior ciliary muscle restriction – A link between trabecular meshwork and optic nerve head pathophysiology

PubMed Central

Lütjen-Drecoll, Elke; Kaufman, Paul L.

2016-01-01

The ciliary muscle plays a major role in controlling both accommodation and outflow facility in primates. The ciliary muscle and the choroid functionally form an elastic network that extends from the trabecular meshwork all the way to the back of the eye and ultimately attaches to the elastic fiber ring that surrounds the optic nerve and to the lamina cribrosa through which the nerve passes. The ciliary muscle governs the accommodative movement of the elastic network. With age ciliary muscle mobility is restricted by progressively inelastic posterior attachments and the posterior restriction makes the contraction progressively isometric; placing increased tension on the optic nerve region. In addition, outflow facility also declines with age and limbal corneoscleral contour bows inward. Age-related loss in muscle movement and altered limbal corneoscleral contour could both compromise the basal function of the trabecular meshwork. Further, recent studies in non-human primates show that the central vitreous moves posteriorly all the way back to the optic nerve region, suggesting a fluid current and a pressure gradient toward the optic nerve. Thus, there may be pressure and tension spikes on the optic nerve region during accommodation and these pressure and tension spikes may increase with age. This constellation of events could be relevant to glaucomatous optic neuropathy. In summary, our hypothesis is that glaucoma and presbyopia may be literally linked to each other, via the choroid, and that damage to the optic nerve may be inflicted by accommodative intraocular pressure and choroidal tension “spikes”, which may increase with age. PMID:27453343

Age-related posterior ciliary muscle restriction - A link between trabecular meshwork and optic nerve head pathophysiology.

PubMed

Croft, Mary Ann; Lütjen-Drecoll, Elke; Kaufman, Paul L

2017-05-01

The ciliary muscle plays a major role in controlling both accommodation and outflow facility in primates. The ciliary muscle and the choroid functionally form an elastic network that extends from the trabecular meshwork all the way to the back of the eye and ultimately attaches to the elastic fiber ring that surrounds the optic nerve and to the lamina cribrosa through which the nerve passes. The ciliary muscle governs the accommodative movement of the elastic network. With age ciliary muscle mobility is restricted by progressively inelastic posterior attachments and the posterior restriction makes the contraction progressively isometric; placing increased tension on the optic nerve region. In addition, outflow facility also declines with age and limbal corneoscleral contour bows inward. Age-related loss in muscle movement and altered limbal corneoscleral contour could both compromise the basal function of the trabecular meshwork. Further, recent studies in non-human primates show that the central vitreous moves posteriorly all the way back to the optic nerve region, suggesting a fluid current and a pressure gradient toward the optic nerve. Thus, there may be pressure and tension spikes on the optic nerve region during accommodation and these pressure and tension spikes may increase with age. This constellation of events could be relevant to glaucomatous optic neuropathy. In summary, our hypothesis is that glaucoma and presbyopia may be literally linked to each other, via the choroid, and that damage to the optic nerve may be inflicted by accommodative intraocular pressure and choroidal tension "spikes", which may increase with age. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of chronic administration of sildenafil citrate (Viagra) on the histology of the retina and optic nerve of adult male rat.

PubMed

Eltony, Sohair A; Abdelhameed, Sally Y

2017-04-01

Abnormal vision has been reported by 3% of patients treated with sildenafil citrate (Viagra). Although many men use Viagra for an extended period for treatment of erectile dysfunction, the implications of the long term-daily use of it on the retina and optic nerve are unclear. To investigate the effect of chronic daily use of sildenafil citrate in a dose equivalent to men preferred therapeutic dose on the histology of the retina and optic nerve of adult male rat. Eighteen adult male Wistar rats were equally divided into three groups. Group I: control. Group II: treated with sildenafil citrate orally (10mg/kg/day) for 8 weeks. Group III (withdrawal): treated as group II and then left for 4 weeks without treatment. Specimens from the retina and optic nerve were processed for light and electron microscopy. In sildenafil citrate treated group, the retina and optic nerve revealed vacuolations and congested blood capillaries with apoptotic endothelial and pericytic cells, and thickened basal lamina. Caspase-3 (apoptotic marker) and CD31 (endothelial marker) expression increased. Glial cells revealed morphological changes: Müller cells lost their processes, activated microglia, astrocytic clasmatodendrosis, degenerated oligodendrocytes surrounded by disintegrated myelin sheathes of the optic nerve fibers. The retina and optic nerve of the withdrawal group revealed less vacuolations and congestion, and partial recovery of the glial cells. Chronic treatment with sildenafil citrate (Viagra) caused toxic effect on the structure of the retina and optic nerve of the rat. Partial recovery was observed after drug withdrawal. Copyright © 2017 Elsevier Ltd. All rights reserved.

Degeneration and regeneration of motor and sensory nerves: a stereological study of crush lesions in rat facial and mental nerves.

PubMed

Barghash, Z; Larsen, J O; Al-Bishri, A; Kahnberg, K-E

2013-12-01

The aim of this study was to evaluate the degeneration and regeneration of a sensory nerve and a motor nerve at the histological level after a crush injury. Twenty-five female Wistar rats had their mental nerve and the buccal branch of their facial nerve compressed unilaterally against a glass rod for 30s. Specimens of the compressed nerves and the corresponding control nerves were dissected at 3, 7, and 19 days after surgery. Nerve cross-sections were stained with osmium tetroxide and toluidine blue and analysed using two-dimensional stereology. We found differences between the two nerves both in the normal anatomy and in the regenerative pattern. The mental nerve had a larger cross-sectional area including all tissue components. The mental nerve had a larger volume fraction of myelinated axons and a correspondingly smaller volume fraction of endoneurium. No differences were observed in the degenerative pattern; however, at day 19 the buccal branch had regenerated to the normal number of axons, whereas the mental nerve had only regained 50% of the normal number of axons. We conclude that the regenerative process is faster and/or more complete in the facial nerve (motor function) than it is in the mental nerve (somatosensory function). Copyright © 2013 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Optic nerve lesion following neuroborreliosis: a case report.

PubMed

Burkhard, C; Gleichmann, M; Wilhelm, H

2001-01-01

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

Intracanalicular Optic Nerve Swelling and Signal Change in Fulminant Untreated Idiopathic Intracranial Hypertension

PubMed Central

Moodley, Anand A.; Dlwati, Mahlubonke S.; Durand, Miranda

2017-01-01

ABSTRACT The role of the optic canal in the pathogenesis of papilloedema has been under scrutiny recently. Whether a larger canal precedes more severe papilloedema or is the result of bone remodelling from chronically raised pressure across a pressure gradient is not clear. The authors present the magnetic resonance imaging findings of a 29-year-old female with fulminant and untreated idiopathic intracranial hypertension. Imaging showed focal expansion and intrinsic signal changes of the intracanalicular optic nerve. The authors discuss the possibility of either fluid accumulation within the optic nerves from a water hammer effect across blocked optic canals resulting from the steep pressure gradient or opticomalacia (optic nerve softening) from chronic ischaemia. PMID:28348630

Bedside Optic Nerve Sheath Diameter Assessment in the Identification of Increased Intracranial Pressure in Suspected Idiopathic Intracranial Hypertension.

PubMed

Irazuzta, Jose E; Brown, Martha E; Akhtar, Javed

2016-01-01

We determined whether the bedside assessment of the optic nerve sheath diameter could identify elevated intracranial pressure in individuals with suspected idiopathic intracranial hypertension. This was a single-center, prospective, rater-blinded study performed in a freestanding pediatric teaching hospital. Patients aged 12 to 18 years scheduled for an elective lumbar puncture with the suspicion of idiopathic intracranial hypertension were eligible to participate. Optic nerve sheath diameter was measured via ultrasonography before performing a sedated lumbar puncture for measuring cerebrospinal fluid opening pressure. Abnormal measurements were predefined as optic nerve sheath diameter ≥4.5 mm and a cerebrospinal fluid opening pressure greater than 20 cmH2O. Thirteen patients participated in the study, 10 of whom had elevated intracranial pressure. Optic nerve sheath diameter was able to predict or rule out elevated intracranial pressure in all patients. Noninvasive assessment of the optic nerve sheath diameter could help to identify patients with elevated intracranial pressure when idiopathic intracranial hypertension is suspected. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparative study of the retinal nerve fibre layer thickness performed with optical coherence tomography and GDx scanning laser polarimetry in patients with primary open-angle glaucoma.

PubMed

Wasyluk, Jaromir T; Jankowska-Lech, Irmina; Terelak-Borys, Barbara; Grabska-Liberek, Iwona

2012-03-01

We compared the parameters of retinal nerve fibre layer in patients with advanced glaucoma with the use of different OCT (Optical Coherence Tomograph) devices in relation to analogical measurements performed with GDx VCC (Nerve Fiber Analyzer with Variable Corneal Compensation) scanning laser polarimetry. Study subjects had advanced primary open-angle glaucoma, previously treated conservatively, diagnosed and confirmed by additional examinations (visual field, ophthalmoscopy of optic nerve, gonioscopy), A total of 10 patients were enrolled (9 women and 1 man), aged 18-70 years of age. Nineteen eyes with advanced glaucomatous neuropathy were examined. 1) Performing a threshold perimetry Octopus, G2 strategy and ophthalmoscopy of optic nerve to confirm the presence of advanced primary open-angle glaucoma; 2) performing a GDx VCC scanning laser polarimetry of retinal nerve fibre layer; 3) measuring the retinal nerve fibre layer thickness with 3 different optical coherence tomographs. The parameters of the retinal nerve fibre layer thickness are highly correlated between the GDx and OCT Stratus and 3D OCT-1000 devices in mean retinal nerve fibre layer thickness, retinal nerve fibre layer thickness in the upper sector, and correlation of NFI (GDx) with mean retinal nerve fibre layer thickness in OCT examinations. Absolute values of the retinal nerve fibre layer thickness (measured in µm) differ significantly between GDx and all OCT devices. Examination with OCT devices is a sensitive diagnostic method of glaucoma, with good correlation with the results of GDx scanning laser polarimetry of the patients.

Vestibulo-oculomotor behaviour in rats following a transient unilateral vestibular loss induced by lidocaine.

PubMed

Magnusson, A K; Tham, R

2003-01-01

The effects of a transient vestibular nerve blockade, achieved by intra-tympanic instillation of lidocaine, were studied in rats by recording horizontal eye movements in darkness. Evaluation of the dose-response relationship showed that a maximal effect was attained with a concentration of 4% lidocaine. Within 15 min of lidocaine instillation, a vigorous spontaneous nystagmus was observed which reached maximal frequency and velocity of the slow phase after about 20 min. Subsequently, the nystagmus failed for approximately half an hour before it reappeared. This could be avoided by providing visual feedback in between the recordings in darkness or by a contralateral instillation of 2.5% lidocaine. It is suggested that the failure reflects an overload of the vestibulo-oculomotor circuits. After recovery from the nerve blockade, when the gaze was stable, dynamic vestibular tests were performed. They revealed that a decrease of the slow phase velocity gain and the dominant time constant during, respectively, sinusoidal- and step stimulation toward the unanaesthetised side, had developed with the nerve blockade. These modulations were impaired by a nodulo-uvulectomy but not by bilateral flocculectomy, which is consistent with the concept of vestibular habituation. A GABA(B) receptor antagonist, CGP 56433A, given systemically during the nerve blockade, aggravated the vestibular asymmetry. The same effect has previously been demonstrated in both short- (days) and long-term (months) compensated rats, by antagonising the GABA(B) receptor. In summary, this study provides the first observations of vestibulo-oculomotor disturbances during the first hour after a rapid and transient unilateral vestibular loss in the rat. By using this method, it is possible to study immediate behavioural consequences and possible neural changes that might outlast the nerve blockade.

Optic Nerve Sheath Mechanics in VIIP Syndrome

NASA Technical Reports Server (NTRS)

Raykin, Julia; Feola, Andrew; Gleason, Rudy; Mulugeta, Lealem; Myers, Jerry; Nelson, Emily; Samuels, Brian; Ethier, C. Ross

2015-01-01

Visual Impairment and Intracranial Pressure (VIIP) syndrome results in a loss of visual function and occurs in astronauts following long-duration spaceflight. Understanding the mechanisms that lead to the ocular changes involved in VIIP is of critical importance for space medicine research. Although the exact mechanisms of VIIP are not yet known, it is hypothesized that microgravity-induced increases in intracranial pressures (ICP) drive the remodeling of the optic nerve sheath, leading to compression of the optic nerve which in turn may reduce visual acuity. Some astronauts present with a kink in the optic nerve after return to earth, suggesting that tissue remodeling in response to ICP increases may be taking place. The goal of this work is to characterize the mechanical properties of the optic nerve sheath (dura mater) to better understand its biomechanical response to increased ICP.

Repair of facial nerve defects with decellularized artery allografts containing autologous adipose-derived stem cells in a rat model.

PubMed

Sun, Fei; Zhou, Ke; Mi, Wen-Juan; Qiu, Jian-Hua

2011-07-20

The purpose of this study was to investigate the effects of a decellularized artery allograft containing autologous adipose-derived stem cells (ADSCs) on an 8-mm facial nerve branch lesion in a rat model. At 8 weeks postoperatively, functional evaluation of unilateral vibrissae movements, morphological analysis of regenerated nerve segments and retrograde labeling of facial motoneurons were all analyzed. Better regenerative outcomes associated with functional improvement, great axonal growth, and improved target reinnervation were achieved in the artery-ADSCs group (2), whereas the cut nerves sutured with artery conduits alone (group 1) achieved inferior restoration. Furthermore, transected nerves repaired with nerve autografts (group 3) resulted in significant recovery of whisking, maturation of myelinated fibers and increased number of labeled facial neurons, and the latter two parameters were significantly different from those of group 2. Collectively, though our combined use of a decellularized artery allograft with autologous ADSCs achieved regenerative outcomes inferior to a nerve autograft, it certainly showed a beneficial effect on promoting nerve regeneration and thus represents an alternative approach for the reconstruction of peripheral facial nerve defects. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

The split hypoglossal nerve versus the cross-face nerve graft to supply the free functional muscle transfer for facial reanimation: A comparative study.

PubMed

Amer, Tarek A; El Kholy, Mohamed S

2018-05-01

Long-standing cases of facial paralysis are currently treated with free functional muscle transfer. Several nerves are mentioned in the literature to supply the free muscle transfer. The aim of this study is to compare the split hypoglossal nerve and the cross-face nerve graft to supply the free functional muscle transfer in facial reanimation. Of 94 patients with long-standing, unilateral facial palsy, 49 were treated using the latissimus dorsi muscle supplied by the split hypoglossal nerve, and 45 patients were treated using the latissmus dorsi muscle supplied by healthy contralateral buccal branch of the facial nerve. The excursion gained by the free muscle transfer supplied by the split hypoglossal nerve (mean 19.20 ± 6.321) was significantly higher (P value 0.001) than that obtained by the contralateral buccal branch of the facial nerve (mean 14.59 ± 6.245). The split hypoglossal nerve appears to be a good possible option to supply the free vascularised muscle transfer in facial reanimation. It yields a stronger excursion in less time than the contralateral cross-face nerve graft. Copyright © 2018 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Diagnosis of unilateral trapezius muscle palsy: 54 Cases.

PubMed

Seror, Paul; Stojkovic, Tanya; Lefevre-Colau, Marie Martine; Lenglet, Timothée

2017-08-01

We assessed medical and surgical causes of unilateral trapezius muscle (TM) palsy and/or wasting. Clinical and electrodiagnostic data were collected in 54 patients with TM impairment over 21 years. In total, 35 cases had a medical origin: neuralgic amyotrophy (NA, n = 22), idiopathic unilateral TM palsy (n = 5), regional neck radiotherapy for different conditions (n = 2), facioscapulohumeral dystrophy (FSH) (n = 4), abnormal loop of the jugular vein (n = 1), or basilar impression (n = 1). Other etiologies were neck surgery (n = 16), cervicofacial lift (n = 2), or trauma (n = 1). There were 5 main diagnostic findings in unilateral TM palsy: (1) dynamic examination of the scapula provides a new clinical sign; (2) NA is the most frequent medical cause; (3) in medical cases, partial preservation of the upper TM can offer good recovery; (4) FSH must be considered, especially in young patients; and (5) minor neck surgery can lead to severe TM palsy. Muscle Nerve 56: 215-223, 2017. © 2016 Wiley Periodicals, Inc.

Human umbilical cord blood mononuclear cells and chorionic plate-derived mesenchymal stem cells promote axon survival in a rat model of optic nerve crush injury

PubMed Central

CHUNG, SOKJOONG; RHO, SEUNGSOO; KIM, GIJIN; KIM, SO-RA; BAEK, KWANG-HYUN; KANG, MYUNGSEO; LEW, HELEN

2016-01-01

The use of mesenchymal stem cells (MSCs) in cell therapy in regenerative medicine has great potential, particularly in the treatment of nerve injury. Umbilical cord blood (UCB) reportedly contains stem cells, which have been widely used as a hematopoietic source and may have therapeutic potential for neurological impairment. Although ongoing research is dedicated to the management of traumatic optic nerve injury using various measures, novel therapeutic strategies based on the complex underlying mechanisms responsible for optic nerve injury, such as inflammation and/or ischemia, are required. In the present study, a rat model of optic nerve crush (ONC) injury was established in order to examine the effects of transplanting human chorionic plate-derived MSCs (CP-MSCs) isolated from the placenta, as well as human UCB mononuclear cells (CB-MNCs) on compressed rat optic nerves. Expression markers for inflammation, apoptosis, and optic nerve regeneration were analyzed, as well as the axon survival rate by direct counting. Increased axon survival rates were observed following the injection of CB-MNCs at at 1 week post-transplantation compared with the controls. The levels of growth-associated protein-43 (GAP-43) were increased after the injection of CB-MNCs or CP-MSCs compared with the controls, and the expression levels of hypoxia-inducible factor-1α (HIF-1α) were also significantly increased following the injection of CB-MNCs or CP-MSCs. ERM-like protein (ERMN) and SLIT-ROBO Rho GTPase activating protein 2 (SRGAP2) were found to be expressed in the optic nerves of the CP-MSC-injected rats with ONC injury. The findings of our study suggest that the administration of CB-MNCs or CP-MSCs may promote axon survival through systemic concomitant mechanisms involving GAP-43 and HIF-1α. Taken together, these findings provide further understanding of the mechanisms repsonsible for optic nerve injury and may aid in the development of novel cell-based therapeutic strategies with future applications in regenerative medicine, particularly in the management of optic nerve disorders. PMID:26986762

Facial nerve paralysis in children

PubMed Central

Ciorba, Andrea; Corazzi, Virginia; Conz, Veronica; Bianchini, Chiara; Aimoni, Claudia

2015-01-01

Facial nerve palsy is a condition with several implications, particularly when occurring in childhood. It represents a serious clinical problem as it causes significant concerns in doctors because of its etiology, its treatment options and its outcome, as well as in little patients and their parents, because of functional and aesthetic outcomes. There are several described causes of facial nerve paralysis in children, as it can be congenital (due to delivery traumas and genetic or malformative diseases) or acquired (due to infective, inflammatory, neoplastic, traumatic or iatrogenic causes). Nonetheless, in approximately 40%-75% of the cases, the cause of unilateral facial paralysis still remains idiopathic. A careful diagnostic workout and differential diagnosis are particularly recommended in case of pediatric facial nerve palsy, in order to establish the most appropriate treatment, as the therapeutic approach differs in relation to the etiology. PMID:26677445

Cyclosporine A does not prevent second-eye involvement in Leber's hereditary optic neuropathy.

PubMed

Leruez, Stéphanie; Verny, Christophe; Bonneau, Dominique; Procaccio, Vincent; Lenaers, Guy; Amati-Bonneau, Patrizia; Reynier, Pascal; Scherer, Clarisse; Prundean, Adriana; Orssaud, Christophe; Zanlonghi, Xavier; Rougier, Marie-Bénédicte; Tilikete, Caroline; Miléa, Dan

2018-02-17

Evaluation of the efficacy of oral cyclosporine A as a prophylactic agent in preventing second-eye involvement in Leber's hereditary optic neuropathy (LHON) in a prospective, open-label, non-randomized, multicenter pilot study. Only LHON patients aged 18 years or more, with confirmed primary mitochondrial DNA mutations and strictly unilateral optic neuropathy occurring within 6 months prior to enrolment, were included in the study. All these patients, receiving treatment with oral cyclosporine (Neoral®, Novartis) at 2.5 mg/kg/day, were examined at three-month intervals for a year. The primary endpoint was the best corrected visual acuity in the unaffected eye; the secondary endpoints were the best corrected visual acuity in the first eye affected, the mean visual field defect on automated perimetry, the thickness of the perifoveal retinal ganglion cell inner plexiform layer, and the thickness of the peripapillary retinal nerve fiber layer in both eyes. Among the 24 patients referred to our institution with genetically confirmed LHON, between July 2011 and April 2014, only five patients, four males and one female, fulfilled the inclusion criteria. Age at enrolment ranged from 19 to 42 years (mean: 27.2 years; median: 26 years), four patients harbored the m.11778G > A pathogenic variant, and one the m.14484 T > C pathogenic variant. The time-interval between the onset of symptoms and inclusion in the study ranged from 7 to 17 weeks (mean: 11.8 weeks; median: 9 weeks). Despite treatment with oral cyclosporine A, all patients eventually experienced bilateral eye involvement, occurring within 11-65 weeks after the initiation of treatment. Over the study time period, the average best corrected visual acuity worsened in the first eye affected; by the end of the study, both eyes were equally affected. Oral cyclosporine, at 2.5 mg/kg/day, did not prevent second-eye involvement in patients with strictly unilateral Leber's hereditary optic neuropathy. ClinicalTrials.gov Identifier: NCT02176733 . Registrated June 25, 2014.

Electrophysiological abnormalities associated with extensive myelinated retinal nerve fibers

PubMed Central

Tay, Su Ann; Sanjay, Srinivasan

2012-01-01

An observational case report of electrophysiological abnormalities in a patient with anisomyopic amblyopia as a result of unilateral extensive myelinated retinal nerve fibers (MNFs) is illustrated. The electrophysiological readings revealed an abnormal pattern electroretinogram (PERG) but normal full-field electroretinogram readings in the affected eye. The visual-evoked potential was also undetectable in that eye. Our findings suggest that extensive MNFs can be associated with electrophysiological abnormalities, in particular the PERG, which can aid in diagnosing the cause of impaired vision when associated with amblyopia. PMID:22824610

An uncommon presentation of an VIII nerve tumor.

PubMed

Swensson, Rubem Cruz; Swensson, Rogério Poli; Pizzini, Fabio Eduardo Caramante; Boldorini, Pedro Robson; Jorge Júnior, José Jarjura

2008-01-01

Vestibular Shwannomas are responsible for 80-90% of the cerebelar-pontine angle tumors and their incidence is of 0.8 to 20.5% of all tumors. Unilateral and progressive hearing loss is the most frequent and premature symptom, and tinnitus is the second most common complaint. Only 5% of the patients have normal audiograms. In this case the patient complained of ipsilateral facial numbness and weak blink, posterior pinna hypoesthesia (Hitzelberger +), tear reduction and positive Romberg test. He also had mouth twisting but no other involvement of other cranial nerves. Hearing acuity was normal.

Effects of adenosine on intraocular pressure, optic nerve head blood flow, and choroidal blood flow in healthy humans.

PubMed

Polska, Elzbieta; Ehrlich, Paulina; Luksch, Alexandra; Fuchsjäger-Mayrl, Gabriele; Schmetterer, Leopold

2003-07-01

There is evidence from a variety of animal studies that the adenosine system plays a role in the control of intraocular pressure (IOP) and ocular blood flow. However, human data on the effect of adenosine on IOP and choroidal and optic nerve blood flow are not available. The effect of stepwise increases in doses of adenosine (10, 20, and 40 micro g/kg per minute, 30 minutes per infusion step) on optic nerve head blood flow, choroidal blood flow, and IOP was determined in a placebo-controlled double-masked clinical trial in 12 healthy male volunteers. Blood flow in the optic nerve head and choroid was measured with laser Doppler flowmetry. In addition, fundus pulsation amplitude in the macula (FPAM) and the optic nerve head (FPAO) were assessed with laser interferometry. Adenosine induced a small but significant decrease in IOP (at 40 microg/kg per minute: 12% +/- 13%), which was significant versus placebo (P = 0.046). In addition, adenosine induced a significant increase in choroidal blood flow (P < 0.001) and optic nerve head blood flow (P = 0.037), and FPAM (P = 0.0014) and tended to increase FPAO (P = 0.057). At the highest administered dose, the effect on choroidal hemodynamic parameters between 14% and 17%, whereas the effect on optic nerve hemodynamic parameters was between 3% and 11%. These data are consistent with adenosine inducing choroidal and optic nerve head vasodilatation and reducing IOP in healthy humans. Considering the neuroprotective properties of adenosine described in previous animal experiments the adenosine system is an attractive target system for therapeutic approaches in glaucoma.

The effects of rearing light level and duration differences on the optic nerve, brain, and associated structures in developing zebrafish larvae: a light and transmission electron microscope study.

PubMed

Chapman, George B; Tarboush, Rania; Connaughton, Victoria P

2012-03-01

The ultrastructure of the optic nerve, brain, and some associated structures of larval zebrafish, grown under three different light regimens were studied. Fish grown under cyclic light (control), constant dark (CD), and constant light (CL) were studied for 4 and 8 days postfertilization (dpf). We also studied the control and CD fish at 15 dpf. The brains of the control and CL fish were larger at 4 dpf than at 8 dpf. In all 4 dpf fish, the brain occupied the entire expanse between the two retinas and the optic nerve extended the shortest distance between the retina and the brain. The 15 dpf zebrafish had the smallest brain size. Groups of skeletal muscle cells associated with the optic nerves became visible in all older larvae. In the 15 dpf larvae, bulges and dilations in the optic nerve occurred as it reached the brain and optic chiasms occurred proximal to the brain. Electron microscopy yielded information about myelinated and unmyelinated axons in the optic nerve, the dimensions of neurotubules, neurofilaments, and myofilaments, including a unique variation in actin myofilaments, and a confirmation of reported myosin myofilament changes (but with dimensions). We also describe the ultrastructure of a sheath-like structure that is confluent over the optic nerve and the brain, which has not been described before in zebrafish. Also presented are images of associated fibroblasts, epithelial cells lining the mouth, cartilage plates, blood vessels, nerve bundles, and skeletal muscle cells, most of which have not been previously described in the literature. Copyright © 2012 Wiley Periodicals, Inc.

Optic chiasm in the species of order Clupeiformes, family Clupeidae: optic chiasm of Spratelloides gracilis shows an opposite laterality to that of Etrumeus teres.

PubMed

Mogi, Kazue; Misawa, Kazuya; Utsunomiya, Kentaro; Kawada, Yuta; Yamazaki, Toshihisa; Takeuchi, Shigeo; Toyoizumi, Ryuji

2009-09-01

In most teleost fishes, the optic nerves decussate completely as they project to the mesencephalic region. Examination of the decussation pattern of 25 species from 11 different orders in Pisces revealed that each species shows a specific chiasmic type. In 11 species out of the 25, laterality of the chiasmic pattern was not determined; in half of the individuals examined, the left optic nerve ran dorsally to the right optic nerve, while in the other half, the right optic nerve was dorsal. In eight other species the optic nerves from both eyes branched into several bundles at the chiasmic point, and intercalated to form a complicated decussation pattern. In the present study we report our findings that Spratelloides gracilis, of the order Clupeiformes, family Clupeidae, shows a particular laterality of decussation: the left optic nerve ran dorsally to the right (n=200/202). In contrast, Etrumeus teres, of the same order and family, had a strong preference of the opposite (complementary) chiasmic pattern to that of S. gracilis (n=59/59), revealing that these two species display opposite left-right optic chiasm patterning. As far as we investigated, other species of Clupeiformes have not shown left-right preference in the decussation pattern. We conclude that the opposite laterality of the optic chiasms of these two closely related species, S. gracilis and E. teres, enables investigation of species-specific laterality in fishes of symmetric shapes.

Optic chiasm in the species of order Clupeiformes, family Clupeidae: Optic chiasm of Spratelloides gracilis shows an opposite laterality to that of Etrumeus teres

PubMed Central

Mogi, Kazue; Misawa, Kazuya; Utsunomiya, Kentaro; Kawada, Yuta; Yamazaki, Toshihisa; Takeuchi, Shigeo; Toyoizumi, Ryuji

2009-01-01

In most teleost fishes, the optic nerves decussate completely as they project to the mesencephalic region. Examination of the decussation pattern of 25 species from 11 different orders in Pisces revealed that each species shows a specific chiasmic type. In 11 species out of the 25, laterality of the chiasmic pattern was not determined; in half of the individuals examined, the left optic nerve ran dorsally to the right optic nerve, while in the other half, the right optic nerve was dorsal. In eight other species the optic nerves from both eyes branched into several bundles at the chiasmic point, and intercalated to form a complicated decussation pattern. In the present study we report our findings that Spratelloides gracilis, of the order Clupeiformes, family Clupeidae, shows a particular laterality of decussation: the left optic nerve ran dorsally to the right (n = 200/202). In contrast, Etrumeus teres, of the same order and family, had a strong preference of the opposite (complementary) chiasmic pattern to that of S. gracilis (n = 59/59), revealing that these two species display opposite left–right optic chiasm patterning. As far as we investigated, other species of Clupeiformes have not shown left–right preference in the decussation pattern. We conclude that the opposite laterality of the optic chiasms of these two closely related species, S. gracilis and E. teres, enables investigation of species-specific laterality in fishes of symmetric shapes. PMID:19229672

Patients affected by endemic pemphigus foliaceus in Colombia, South America exhibit autoantibodies to optic nerve sheath envelope cell junctions.

PubMed

Abreu-Velez, Ana Maria; Gao, Wendy; Howard, Michael S

2018-01-01

The majority of the patients affected by a new variant of endemic pemphigus foliaceus in El Bagre, Colombia (El Bagre EPF or pemphigus Abreu-Manu), have experienced vision problems; we have previously reported several ocular abnormalities. Here, we aimed to investigate reactivity to optic nerves in these patients. We utilized bovine, rat and mouse optic nerves, and performed immunofluorescence and confocal microscopy to test for optical nerve autoreactivity. We tested 45 patients affected by this disease and 45 controls from the endemic area matched by age, sex and work activity. Overall, 37 of the 45 patient sera reacted to the optic nerve envelope that is composed of leptomeninges; the reactivity was polyclonal and present mostly at the cell junctions (P < 0.001). The immune response was directed against optic nerve sheath cell junctions and the vessels inside it, as well as other molecules inside the nerve. No control cases were positive. Of interest, all the patient autoantibodies co-localized with commercial antibodies to desmoplakins I-II, myocardium-enriched zonula occludens-1- associated protein (MYZAP), armadillo repeat gene deleted in velo-cardio-facial syndrome (ARVCF), and plakophilin-4 (p0071) from Progen Biotechnik (P < 0.001). We conclude that the majority of the patients affected by pemphigus Abreu-Manu have autoantibodies to optic nerve sheath envelope cell junctions. These antibodies also co-localize with armadillo repeat gene deleted in velo-cardio-facial syndrome, p0071 and desmoplakins I-II. The clinical significance of our findings remains unknown.

Comparative study of the retinal nerve fibre layer thickness performed with optical coherence tomography and GDx scanning laser polarimetry in patients with primary open-angle glaucoma

PubMed Central

Wasyluk, Jaromir T.; Jankowska-Lech, Irmina; Terelak-Borys, Barbara; Grabska-Liberek, Iwona

2012-01-01

Summary Background We compared the parameters of retinal nerve fibre layer in patients with advanced glaucoma with the use of different OCT (Optical Coherence Tomograph) devices in relation to analogical measurements performed with GDx VCC (Nerve Fiber Analyzer with Variable Corneal Compensation) scanning laser polarimetry. Material/Methods Study subjects had advanced primary open-angle glaucoma, previously treated conservatively, diagnosed and confirmed by additional examinations (visual field, ophthalmoscopy of optic nerve, gonioscopy), A total of 10 patients were enrolled (9 women and 1 man), aged 18–70 years of age. Nineteen eyes with advanced glaucomatous neuropathy were examined. 1) Performing a threshold perimetry Octopus, G2 strategy and ophthalmoscopy of optic nerve to confirm the presence of advanced primary open-angle glaucoma; 2) performing a GDx VCC scanning laser polarimetry of retinal nerve fibre layer; 3) measuring the retinal nerve fibre layer thickness with 3 different optical coherence tomographs. Results The parameters of the retinal nerve fibre layer thickness are highly correlated between the GDx and OCT Stratus and 3D OCT-1000 devices in mean retinal nerve fibre layer thickness, retinal nerve fibre layer thickness in the upper sector, and correlation of NFI (GDx) with mean retinal nerve fibre layer thickness in OCT examinations. Absolute values of the retinal nerve fibre layer thickness (measured in μm) differ significantly between GDx and all OCT devices. Conclusions Examination with OCT devices is a sensitive diagnostic method of glaucoma, with good correlation with the results of GDx scanning laser polarimetry of the patients. PMID:22367131

Optic neuritis in dogs: 96 cases (1983-2016).

PubMed

Smith, Sara M; Westermeyer, Hans D; Mariani, Christopher L; Gilger, Brian C; Davidson, Michael G

2017-12-18

To characterize ocular and neurologic findings, causes, and treatment outcomes of dogs with optic neuritis. Medical records from dogs with a diagnosis of optic neuritis at North Carolina State University, College of Veterinary Medicine, Veterinary Hospital between 1983 and 2016 were reviewed. Ninety-six cases (20 unilateral, 76 bilateral), comprised of 38 males and 58 females with a mean age of 6.1 ± 3.0 years (range 0.5-13), were identified. Seventy-four cases were presented for vision loss, and 42 had other concurrent neurologic abnormalities. Funduscopic findings included optic nerve head elevation (n = 92), peripapillary retinal edema or separation (n = 37), retinal hemorrhage or dilation of retinal vasculature (n = 23), and multiple inflammatory foci in the peripapillary region (n = 13). Retrobulbar optic neuritis was diagnosed in four cases. The final diagnoses included the following: multifocal meningoencephalitis of unknown etiology (MUE, n = 35), isolated optic neuritis (I-ON, n = 42), neoplasia (n = 10), microbial infection (n = 6), orbital inflammation (n = 2), and suspected ivermectin toxicosis (n = 1). Dogs with I-ON were more commonly male, and medium-to-large breed, when compared to dogs with MUE. Follow-up was available in 72 cases, 50 of which remained blind, 10 had partial visual improvement, and 12 were assessed as having normal vision in the affected eye(s). Optic neuritis was most commonly associated with multifocal MUE or was isolated as the sole neurologic finding, with a similar incidence between the two groups. Findings suggest that a clinical syndrome of isolated optic neuritis, distinct from multifocal MUE, occurs in dogs. © 2017 American College of Veterinary Ophthalmologists.

Birefringence measurement of retinal nerve fiber layer using polarization-sensitive spectral domain optical coherence tomography with Jones matrix based analysis

NASA Astrophysics Data System (ADS)

Yamanari, Masahiro; Miura, Masahiro; Makita, Shuichi; Yatagai, Toyohiko; Yasuno, Yoshiaki

2007-02-01

Birefringence of retinal nerve fiber layer is measured by polarization-sensitive spectral domain optical coherence tomography using the B-scan-oriented polarization modulation method. Birefringence of the optical fiber and the cornea is compensated by Jones matrix based analysis. Three-dimensional phase retardation map around the optic nerve head and en-face phase retardation map of the retinal nerve fiber layer are shown. Unlike scanning laser polarimetry, our system can measure the phase retardation quantitatively without using bow-tie pattern of the birefringence in the macular region, which enables diagnosis of glaucoma even if the patients have macular disease.

Bilateral vision loss in a captive cheetah (Acinonyx jubatus).

PubMed

Walser-Reinhardt, Ladina; Wernick, Morena B; Hatt, Jean-Michel; Spiess, Bernhard M

2010-09-01

The following case report describes a 1-year-old female cheetah (Acinonyx jubatus) with bilateral blindness and unresponsive pupils. For comparison, a second healthy 2.5-year-old male cheetah without visual deficits was also examined. Clinical examination of both animals included biomicroscopy, indirect ophthalmoscopy, tonometry, and electroretinography. The young female cheetah showed no menace response, no direct or indirect pupillary light reflex, and no dazzle reflex in either eye. Fundus lesions, as detected by indirect ophthalmoscopy, are described for the female animal. In both eyes, the fundus color was green/turquoise/yellow with multiple hyperpigmented linear lesions in the tapetal area around the optic nerve. The optic nerve head was dark gray and about half the normal size suggesting bilateral optic nerve hypoplasia and retinal dysplasia or differentially optic nerve atrophy and chorioretinal scarring. The ERG had low amplitudes in the right eye but appeared normal in the left eye compared with the male cheetah. Blood levels did not suggest current taurine deficiency. This is addressed to some degree in the discussion. Bilateral optic nerve hypoplasia or optic nerve atrophy is a rare anomaly in cats and has not yet been described in a cheetah.

Bilateral Abducent Nerve Palsy After Neck Trauma: A Case Report

PubMed Central

Aminiahidashti, Hamed; Shafiee, Sajad; Sazegar, Mohammad; Nosrati, Nazanin

2016-01-01

Introduction The abducent nucleus is located in the upper part of the rhomboid fossa beneath the fourth ventricle in the caudal portion of the pons. The abducent nerve courses from its nucleus, to innervate the lateral rectus muscle. This nerve has the longest subarachnoid course of all the cranial nerves, it is the cranial nerve most vulnerable to trauma. It has been reported that 1% to 2.7% of all head injuries are followed by unilateral abducent palsy, but bilateral abducent nerve palsy is extremely rare. Case Presentation A 65-year-old woman presented to the emergency department following a motor vehicle accident. A neurological assessment showed the patient’s Glascow coma scale (GCS) to be 15. She complained of double vision, and we found lateral gaze palsy in both eyes. A hangman fracture type IIA (C2 fracture with posterior ligamentous C1 - C2 distraction) was found on the cervical CT scan. A three-month follow-up of the patient showed complete recovery of the abducent nerve. Conclusions Conservative treatment is usually recommended for traumatic bilateral abducent nerve palsy. Our patient recovered from this condition after three months without any remaining neurological deficit, a very rare outcome in a rare case. PMID:27218062

Vocal cord collapse during phrenic nerve-paced respiration in congenital central hypoventilation syndrome.

PubMed

Domanski, Mark C; Preciado, Diego A

2012-01-01

Phrenic nerve pacing can be used to treat congenital central hypoventilation syndrome (CCHS). We report how the lack of normal vocal cord tone during phrenic paced respiration can result in passive vocal cord collapse and produce obstructive symptoms. We describe a case of passive vocal cord collapse during phrenic nerve paced respiration in a patient with CCHS. As far as we know, this is the first report of this etiology of airway obstruction. The patient, a 7-year-old with CCHS and normal waking vocal cord movement, continued to require nightly continuous positive airway pressure (CPAP) despite successful utilization of phrenic nerve pacers. On direct laryngoscopy, the patient's larynx was observed while the diaphragmatic pacers were sequentially engaged. No abnormal vocal cord stimulation was witnessed during engaging of either phrenic nerve stimulator. However, the lack of normal inspiratory vocal cord abduction during phrenic nerve-paced respiration resulted in vocal cord collapse and partial obstruction due to passive adduction of the vocal cords through the Bernoulli effect. Bilateral phrenic nerve stimulation resulted in more vocal cord collapse than unilateral stimulation. The lack of vocal cord abduction on inspiration presents a limit to phrenic nerve pacers.

Adipose-derived mesenchymal stem cells accelerate nerve regeneration and functional recovery in a rat model of recurrent laryngeal nerve injury.

PubMed

Li, Yun; Xu, Wen; Cheng, Li-Yu

2017-09-01

Medialization thyroplasty or injection laryngoplasty for unilateral vocal fold paralysis cannot restore mobility of the vocal fold. Recent studies have shown that transplantation of mesenchymal stem cells is effective in the repair of nerve injuries. This study investigated whether adipose-derived stem cell transplantation could repair recurrent laryngeal nerve injury. Rat models of recurrent laryngeal nerve injury were established by crushing with micro forceps. Adipose-derived mesenchymal stem cells (ADSCs; 8 × 10 5 ) or differentiated Schwann-like adipose-derived mesenchymal stem cells (dADSCs; 8 × 10 5 ) or extracellular matrix were injected at the site of injury. At 2, 4 and 6 weeks post-surgery, a higher density of myelinated nerve fiber, thicker myelin sheath, improved vocal fold movement, better recovery of nerve conduction capacity and reduced thyroarytenoid muscle atrophy were found in ADSCs and dADSCs groups compared with the extracellular matrix group. The effects were more pronounced in the ADSCs group than in the dADSCs group. These experimental results indicated that ADSCs transplantation could be an early interventional strategy to promote regeneration after recurrent laryngeal nerve injury.

Neurofibromatosis with unilateral lower limb gigantism.

PubMed

Sabbioni, Giacomo; Rani, Nicola; Devescovi, Valentina

2010-05-01

The case of a 3-year-old child diagnosed with Type 1 neurofibromatosis is presented, showing pigmented birthmarks and gigantism of the left lower limb associated with the presence of multiple neurofibromas. Increased bone growth appears to be the direct or indirect consequence of a still undefined paracrine effect of nerve tumor cells.

Coincidental Optic Nerve Meningioma and Thyroid Eye Disease.

PubMed

Garg, Aakriti; Patel, Payal; Lignelli, Angela; Baron, Edward; Kazim, Michael

2015-01-01

A 57-year-old woman with diabetes mellitus, hypertension, obesity, and Graves disease presented with clinical evidence of thyroid eye disease (TED) and optic neuropathy. She was referred when a tapered dose of steroids prompted worsening of her TED. CT and MRI were consistent with TED and bilateral optic nerve meningioma. To the authors' knowledge, this is the first reported case of concurrent TED and unsuspected bilateral optic nerve meningioma. When investigating the etiology of TED-associated optic neuropathy, careful attention to orbital imaging is required because coexisting pathology may exist.

Adeno-Associated Viral-Mediated Catalase Expression Suppresses Optic Neuritis in Experimental Allergic Encephalomyelitis

NASA Astrophysics Data System (ADS)

Guy, John; Qi, Xiaoping; Hauswirth, William W.

1998-11-01

Suppression of oxidative injury by viral-mediated transfer of the human catalase gene was tested in the optic nerves of animals with experimental allergic encephalomyelitis (EAE). EAE is an inflammatory autoimmune disorder of primary central nervous system demyelination that has been frequently used as an animal model for the human disease multiple sclerosis (MS). The optic nerve is a frequent site of involvement common to both EAE and MS. Recombinant adeno-associated virus containing the human gene for catalase was injected over the right optic nerve heads of SJL/J mice that were simultaneously sensitized for EAE. After 1 month, cell-specific catalase activity, evaluated by quantitation of catalase immunogold, was increased approximately 2-fold each in endothelia, oligodendroglia, astrocytes, and axons of the optic nerve. Effects of catalase on the histologic lesions of EAE were measured by computerized analysis of the myelin sheath area (for demyelination), optic disc area (for optic nerve head swelling), extent of the cellular infiltrate, extravasated serum albumin labeled by immunogold (for blood-brain barrier disruption), and in vivo H2O2 reaction product. Relative to control, contralateral optic nerves injected with the recombinant virus without a therapeutic gene, catalase gene inoculation reduced demyelination by 38%, optic nerve head swelling by 29%, cellular infiltration by 34%, disruption of the blood-brain barrier by 64%, and in vivo levels of H2O2 by 61%. Because the efficacy of potential treatments for MS are usually initially tested in the EAE animal model, this study suggests that catalase gene delivery by using viral vectors may be a therapeutic strategy for suppression of MS.

Targeted Metabolomics Reveals Early Dominant Optic Atrophy Signature in Optic Nerves of Opa1delTTAG/+ Mice.

PubMed

Chao de la Barca, Juan Manuel; Simard, Gilles; Sarzi, Emmanuelle; Chaumette, Tanguy; Rousseau, Guillaume; Chupin, Stéphanie; Gadras, Cédric; Tessier, Lydie; Ferré, Marc; Chevrollier, Arnaud; Desquiret-Dumas, Valérie; Gueguen, Naïg; Leruez, Stéphanie; Verny, Christophe; Miléa, Dan; Bonneau, Dominique; Amati-Bonneau, Patrizia; Procaccio, Vincent; Hamel, Christian; Lenaers, Guy; Reynier, Pascal; Prunier-Mirebeau, Delphine

2017-02-01

Dominant optic atrophy (MIM No. 165500) is a blinding condition related to mutations in OPA1, a gene encoding a large GTPase involved in mitochondrial inner membrane dynamics. Although several mouse models mimicking the disease have been developed, the pathophysiological mechanisms responsible for retinal ganglion cell degeneration remain poorly understood. Using a targeted metabolomic approach, we measured the concentrations of 188 metabolites in nine tissues, that is, brain, three types of skeletal muscle, heart, liver, retina, optic nerve, and plasma in symptomatic 11-month-old Opa1delTTAG/+ mice. Significant metabolic signatures were found only in the optic nerve and plasma of female mice. The optic nerve signature was characterized by altered concentrations of phospholipids, amino acids, acylcarnitines, and carnosine, whereas the plasma signature showed decreased concentrations of amino acids and sarcosine associated with increased concentrations of several phospholipids. In contrast, the investigation of 3-month-old presymptomatic Opa1delTTAG/+ mice showed no specific plasma signature but revealed a significant optic nerve signature in both sexes, although with a sex effect. The Opa1delTTAG/+ versus wild-type optic nerve signature was characterized by the decreased concentrations of 10 sphingomyelins and 10 lysophosphatidylcholines, suggestive of myelin sheath alteration, and by alteration in the concentrations of metabolites involved in neuroprotection, such as dimethylarginine, carnitine, spermine, spermidine, carnosine, and glutamate, suggesting a concomitant axonal metabolic dysfunction. Our comprehensive metabolomic investigations revealed in symptomatic as well as in presymptomatic Opa1delTTAG/+ mice, a specific sensitiveness of the optic nerve to Opa1 insufficiency, opening new routes for protective therapeutic strategies.

Effects of a facial nerve lesion on responses in forehead microvessels to conjunctival irritation and paced breathing.

PubMed

Drummond, Peter D

2012-08-16

To investigate parasympathetic influences on the forehead microvasculature, blood flow was monitored bilaterally in seven participants with a unilateral facial nerve lesion during conjunctival irritation with Schirmer's strips and while breathing at 0.15 Hz. Blood flow and slow-wave frequency increased on the intact side of the forehead during Schirmer's test but did not change on the denervated side. However, a 0.15 Hz vascular wave strengthened during paced breathing, particularly on the denervated side. These findings indicate that parasympathetic activity in the facial nerve increases forehead blood flow during minor conjunctival irritation, but may interfere with the 0.15 Hz vascular wave. Copyright © 2012 Elsevier B.V. All rights reserved.

Acute common peroneal neuropathy due to hand positioning in normal labor and delivery.

PubMed

Radawski, Melissa M; Strakowski, Jeffrey A; Johnson, Ernest W

2011-08-01

Foot drop has been described as an infrequent complication from common peroneal nerve injury related to external compression and forceful knee flexion while pushing during vaginal delivery. Past recommendations include placing the hands at the posterior thighs rather than the legs to avoid this complication. A 32-year-old woman developed unilateral foot drop after vaginal delivery. Electromyography was diagnostic for an acute compression neuropathy of the common peroneal nerve above the knee. The patient's likely mechanism of injury occurred during delivery from external compression by the patient's dominant hand to the distal posterior thigh while under epidural anesthesia. Labor and delivery teams should be aware that nerve injury is also possible at the distal thigh with excessive external pressure.

Temperature-controlled optical stimulation of the rat prostate cavernous nerves

NASA Astrophysics Data System (ADS)

Tozburun, Serhat; Hutchens, Thomas C.; McClain, Michael A.; Lagoda, Gwen A.; Burnett, Arthur L.; Fried, Nathaniel M.

2013-06-01

Optical nerve stimulation (ONS) may be useful as a diagnostic tool for intraoperative identification and preservation of the prostate cavernous nerves (CN), responsible for erectile function, during prostate cancer surgery. Successful ONS requires elevating the nerve temperature to within a narrow range (˜42 to 47°C) for nerve activation without thermal damage to the nerve. This preliminary study explores a prototype temperature-controlled optical nerve stimulation (TC-ONS) system for maintaining a constant (±1°C) nerve temperature during short-term ONS of the rat prostate CNs. A 150-mW, 1455-nm diode laser was operated in continuous-wave mode, with and without temperature control, during stimulation of the rat CNs for 15 to 30 s through a fiber optic probe with a 1-mm-diameter spot. A microcontroller opened and closed an in-line mechanical shutter in response to an infrared sensor, with a predetermined temperature set point. With TC-ONS, higher laser power settings were used to rapidly and safely elevate the CNs to a temperature necessary for a fast intracavernous pressure response, while also preventing excessive temperatures that would otherwise cause thermal damage to the nerve. With further development, TC-ONS may provide a rapid, stable, and safe method for intraoperative identification and preservation of the prostate CNs.

[Diaphragm pacing for the ventilatory support of the quadriplegic patients with respiratory paralysis].

PubMed

Cheng, H; Wang, L S; Pan, H C; Shoung, H M; Lee, L S

1992-02-01

Electrical stimulation of the phrenic nerve to pace the diaphragm in patients with chronic ventilatory insufficiency has been an established therapeutic modality since William W.L. Glenn first described using radiofrequency signals in 1978 to stimulate the phrenic nerves. Before this event, patients who were ventilator-dependent and thus bedridden because of respiratory paralysis associated with quadriplegia usually anticipated little chance for physical or psychosocial rehabilitation. Two cases of C1-C2 subluxtion with cord injury and chronic ventilatory insufficiency were implanted at VGH-Taipei with diaphragm pacemaker in 1988. Postoperative phrenic nerve stimulation was given according to individual training schedule. One case with total phrenic paralysis received bilateral phrenic nerve stimulation and became weaned from the ventilator 6 months later. The other case with partially active ventilatory function received unilateral phrenic nerve stimulation to compensate the ventilation. However, its final outcome still showed the necessity of a bilateral mode to achieve adequate ventilation irrespective of strenuous training for 2 years.

Magnetic resonance imaging-a diagnostic tool for postoperative evaluation of dental implants: a case report.

PubMed

Wanner, Laura; Ludwig, Ute; Hövener, Jan-Bernd; Nelson, Katja; Flügge, Tabea

2018-04-01

Compared with cone beam computed tomography (CBCT), magnetic resonance imaging (MRI) might be superior for the diagnosis of nerve lesions associated with implant placement. A patient presented with unilateral pain associated with dysesthesia in the region of the right lower lip and chin after implant placement. Conventional orthopantomography could not identify an association between the position of the inferior alveolar nerve and the implant. For 3-dimensional display of the implant in relation to the surrounding anatomy, CBCT was compared with MRI. MRI enabled the precise depiction of the implant position and its spatial relation to the inferior alveolar nerve, whereas the nerve position and its exact course within the mandible could not be directly displayed in CBCT. MRI may be a valuable, radiation-free diagnostic tool for the visualization of intraoral hard and soft tissues, offering an objective assessment of nerve injuries by a direct visualization of the inferior alveolar neurovascular bundle. Copyright © 2018 Elsevier Inc. All rights reserved.

Assessment of nerve ultrastructure by fibre-optic confocal microscopy.

PubMed

Cushway, T R; Lanzetta, M; Cox, G; Trickett, R; Owen, E R

1996-01-01

Fibre-optic technology combined with confocality produces a microscope capable of optical thin sectioning. In this original study, tibial nerves have been stained in a rat model with a vital dye, 4-(4-diethylaminostyryl)-N-methylpyridinium iodide, and analysed by fibre-optic confocal microscopy to produce detailed images of nerve ultrastructure. Schwann cells, nodes of Ranvier and longitudinal myelinated sheaths enclosing axons were clearly visible. Single axons appeared as brightly staining longitudinal structures. This allowed easy tracing of multiple signal axons within the nerve tissue. An accurate measurement of internodal lengths was easily accomplished. This technique is comparable to current histological techniques, but does not require biopsy, thin sectioning or tissue fixing. This study offers a standard for further in vivo microscopy, including the possibility of monitoring the progression of nerve regeneration following microsurgical neurorraphy.

Optic Nerve Sheath Mechanics in VIIP Syndrome

NASA Technical Reports Server (NTRS)

Raykin, Julia; Forte, Taylor E.; Wang, Roy; Feola, Andrew; Samuels, Brian; Myers, Jerry; Nelson, Emily; Gleason, Rudy; Ethier, C. Ross

2016-01-01

Visual Impairment Intracranial Pressure (VIIP) syndrome is a major concern in current space medicine research. While the exact pathology of VIIP is not yet known, it is hypothesized that the microgravity-induced cephalad fluid shift increases intracranial pressure (ICP) and drives remodeling of the optic nerve sheath. To investigate this possibility, we are culturing optic nerve sheath dura mater samples under different pressures and investigating changes in tissue composition. To interpret results from this work, it is essential to first understand the biomechanical response of the optic nerve sheath dura mater to loading. Here, we investigated the effects of mechanical loading on the porcine optic nerve sheath.Porcine optic nerves (number: 6) were obtained immediately after death from a local abattoir. The optic nerve sheath (dura mater) was isolated from the optic nerve proper, leaving a hollow cylinder of connective tissue that was used for biomechanical characterization. We developed a custom mechanical testing system that allowed for unconfined lengthening, twisting, and circumferential distension of the dura mater during inflation and under fixed axial loading. To determine the effects of variations in ICP, the sample was inflated (0-60 millimeters Hg) and circumferential distension was simultaneously recorded. These tests were performed under variable axial loads (0.6 grams - 5.6 grams at increments of 1 gram) by attaching different weights to one end of the dura mater. Results and Conclusions: The samples demonstrated nonlinear behavior, similar to other soft connective tissue (Figure 1). Large increases in diameter were observed at lower transmural pressures (approximately 0 to 5 millimeters Hg), whereas only small diameter changes were observed at higher pressures. Particularly interesting was the existence of a cross-over point at a pressure of approximately 11 millimeters Hg. At this pressure, the same diameter is obtained for all axial loads applied to the tissue; i.e., as the axial load is varied, the diameter of the dura mater remains constant. This cross-over in the pressure-diameter curves occurred in all optic nerve sheaths that were tested, and may correspond with in vivo ICP levels for pigs. These data suggest that diameter of the dura mater of the optic nerve remains nearly constant in vivo despite being stretched axially. This may be a homeostatic mechanism aimed at maintaining target stresses/strains on the cells in the dura mater, and deviations from these stresses may play an important role in optic nerve sheath remodeling. Future studies will involve subjecting the dura mater to varying pressures and axial tensions for extended periods of time, while monitoring changes in the biomechanical properties. The data can then be used to study the effects of changes in ICP on the remodeling of the dura mater.

Optical cuff for optogenetic control of the peripheral nervous system.

PubMed

Michoud, Frédéric; Sottas, Loïc; Browne, Liam E; Asboth, Léonie; Latremoliere, Alban; Sakuma, Miyuki; Courtine, Grégoire; Woolf, Clifford J; Lacour, Stéphanie P

2018-02-01

Nerves in the peripheral nervous system (PNS) contain axons with specific motor, somatosensory and autonomic functions. Optogenetics offers an efficient approach to selectively activate axons within the nerve. However, the heterogeneous nature of nerves and their tortuous route through the body create a challenging environment to reliably implant a light delivery interface. Here, we propose an optical peripheral nerve interface-an optocuff-, so that optogenetic modulation of peripheral nerves become possible in freely behaving mice. Using this optocuff, we demonstrate orderly recruitment of motor units with epineural optical stimulation of genetically targeted sciatic nerve axons, both in anaesthetized and in awake, freely behaving animals. Behavioural experiments and histology show the optocuff does not damage the nerve thus is suitable for long-term experiments. These results suggest that the soft optocuff might be a straightforward and efficient tool to support more extensive study of the PNS using optogenetics.

Optical cuff for optogenetic control of the peripheral nervous system

NASA Astrophysics Data System (ADS)

Michoud, Frédéric; Sottas, Loïc; Browne, Liam E.; Asboth, Léonie; Latremoliere, Alban; Sakuma, Miyuki; Courtine, Grégoire; Woolf, Clifford J.; Lacour, Stéphanie P.

2018-02-01

Objective. Nerves in the peripheral nervous system (PNS) contain axons with specific motor, somatosensory and autonomic functions. Optogenetics offers an efficient approach to selectively activate axons within the nerve. However, the heterogeneous nature of nerves and their tortuous route through the body create a challenging environment to reliably implant a light delivery interface. Approach. Here, we propose an optical peripheral nerve interface—an optocuff—, so that optogenetic modulation of peripheral nerves become possible in freely behaving mice. Main results. Using this optocuff, we demonstrate orderly recruitment of motor units with epineural optical stimulation of genetically targeted sciatic nerve axons, both in anaesthetized and in awake, freely behaving animals. Behavioural experiments and histology show the optocuff does not damage the nerve thus is suitable for long-term experiments. Significance. These results suggest that the soft optocuff might be a straightforward and efficient tool to support more extensive study of the PNS using optogenetics.

Phrenic Nerve Palsy as Initial Presentation of Large Retrosternal Goitre.

PubMed

Hakeem, Arsheed Hussain; Hakeem, Imtiyaz Hussain; Wani, Fozia Jeelani

2016-12-01

Unilateral phrenic nerve palsy as initial presentation of the retrosternal goitre is extremely rare event. This is a case report of a 57-year-old woman with history of cough and breathlessness of 3 months duration, unaware of the thyroid mass. She had large cervico-mediastinal goiter and chest radiograph revealed raised left sided hemidiaphragm. Chest CT scan did not reveal any lung parenchymal or mediastinal pathology. The patient underwent a total thyroidectomy through a cervical approach. The final pathology was in favor of multinodular goitre. Even after 1 year of follow up, phrenic nerve palsy did not improve indicating permanent damage. Phrenic nerve palsy as initial presentation of the retrosternal goitre is unusual event. This case is reported not only because of the rare nature of presentation, but also to make clinicians aware of the entity so that early intervention may prevent attendant morbidity.

[Clinical evaluation of the optic disc in glaucoma].

PubMed

Greslechner, R; Spiegel, D

2016-10-01

Glaucoma is defined as a progressive neuropathy of the optic nerve, characterized by specific changes of the optic disc, parapapillary region, and retinal nerve fiber layer. Characteristic glaucomatous changes of the optic disc, parapapillary region, and retinal nerve fiber layer are discussed and their ophthalmoscopic examination is described. A literature search in the PubMed database was conducted. A systematic step-by-step approach to a qualitative and quantitative ophthalmoscopic evaluation of the optic disc regarding glaucomatous damage is presented. A systematic, clinical, qualitative, and quantitative assessment of the optic disc can be performed with little effort and forms the basis for diagnosis and treatment of glaucoma.

Automated Axon Counting in Rodent Optic Nerve Sections with AxonJ.

PubMed

Zarei, Kasra; Scheetz, Todd E; Christopher, Mark; Miller, Kathy; Hedberg-Buenz, Adam; Tandon, Anamika; Anderson, Michael G; Fingert, John H; Abràmoff, Michael David

2016-05-26

We have developed a publicly available tool, AxonJ, which quantifies the axons in optic nerve sections of rodents stained with paraphenylenediamine (PPD). In this study, we compare AxonJ's performance to human experts on 100x and 40x images of optic nerve sections obtained from multiple strains of mice, including mice with defects relevant to glaucoma. AxonJ produced reliable axon counts with high sensitivity of 0.959 and high precision of 0.907, high repeatability of 0.95 when compared to a gold-standard of manual assessments and high correlation of 0.882 to the glaucoma damage staging of a previously published dataset. AxonJ allows analyses that are quantitative, consistent, fully-automated, parameter-free, and rapid on whole optic nerve sections at 40x. As a freely available ImageJ plugin that requires no highly specialized equipment to utilize, AxonJ represents a powerful new community resource augmenting studies of the optic nerve using mice.

Automated Axon Counting in Rodent Optic Nerve Sections with AxonJ

NASA Astrophysics Data System (ADS)

Zarei, Kasra; Scheetz, Todd E.; Christopher, Mark; Miller, Kathy; Hedberg-Buenz, Adam; Tandon, Anamika; Anderson, Michael G.; Fingert, John H.; Abràmoff, Michael David

2016-05-01

We have developed a publicly available tool, AxonJ, which quantifies the axons in optic nerve sections of rodents stained with paraphenylenediamine (PPD). In this study, we compare AxonJ’s performance to human experts on 100x and 40x images of optic nerve sections obtained from multiple strains of mice, including mice with defects relevant to glaucoma. AxonJ produced reliable axon counts with high sensitivity of 0.959 and high precision of 0.907, high repeatability of 0.95 when compared to a gold-standard of manual assessments and high correlation of 0.882 to the glaucoma damage staging of a previously published dataset. AxonJ allows analyses that are quantitative, consistent, fully-automated, parameter-free, and rapid on whole optic nerve sections at 40x. As a freely available ImageJ plugin that requires no highly specialized equipment to utilize, AxonJ represents a powerful new community resource augmenting studies of the optic nerve using mice.

Evolution of an Astrocytic Hamartoma of the Optic Nerve Head in a Patient with Retinitis Pigmentosa - Photographic Documentation over 2 Years of Follow-Up.

PubMed

Loukianou, Eleni; Kisma, Nacima; Pal, Bishwanathan

2011-02-02

To report photographically the evolution of an astrocytic hamartoma of the left optic nerve head over a 2-year follow-up in a patient with retinitis pigmentosa. A 14-year-old boy was seen in the medical retina clinic with a 3-year history of night blindness. Best corrected visual acuity was 6/18 in both eyes. Colour vision was normal in both eyes and confrontation fields showed peripheral constriction. Fundus examination revealed bone spicule pigmentary changes at the retinal mid periphery typical of retinitis pigmentosa and superficial globules at the margins of both optic nerve heads. Electrodiagnostic tests confirmed moderately severe rod cone dystrophy with macular involvement bilaterally. Two years later, the ocular examination was unchanged except for the appearance of the optic nerve head lesion in the left eye. There was an increase in the size of the lesion which was diagnosed as an astrocytic hamartoma. Further investigations were recommended to exclude neurofibromatosis and tuberous sclerosis. Astrocytic hamartomas of the optic nerve head and optic nerve head drusen have both been described in patients with retinitis pigmentosa. They can be a diagnostic dilemma although drusen are more common (10%). To differentiate these two entities it is very important to document any growth during the follow-up period which is suggestive of astrocytic hamartoma rather than optic disc drusen.

Ultrahigh-Speed Optical Coherence Tomography for Three-Dimensional and En Face Imaging of the Retina and Optic Nerve Head

PubMed Central

Srinivasan, Vivek J.; Adler, Desmond C.; Chen, Yueli; Gorczynska, Iwona; Huber, Robert; Duker, Jay S.; Schuman, Joel S.; Fujimoto, James G.

2009-01-01

Purpose To demonstrate ultrahigh-speed optical coherence tomography (OCT) imaging of the retina and optic nerve head at 249,000 axial scans per second and a wavelength of 1060 nm. To investigate methods for visualization of the retina, choroid, and optic nerve using high-density sampling enabled by improved imaging speed. Methods A swept-source OCT retinal imaging system operating at a speed of 249,000 axial scans per second was developed. Imaging of the retina, choroid, and optic nerve were performed. Display methods such as speckle reduction, slicing along arbitrary planes, en face visualization of reflectance from specific retinal layers, and image compounding were investigated. Results High-definition and three-dimensional (3D) imaging of the normal retina and optic nerve head were performed. Increased light penetration at 1060 nm enabled improved visualization of the choroid, lamina cribrosa, and sclera. OCT fundus images and 3D visualizations were generated with higher pixel density and less motion artifacts than standard spectral/Fourier domain OCT. En face images enabled visualization of the porous structure of the lamina cribrosa, nerve fiber layer, choroid, photoreceptors, RPE, and capillaries of the inner retina. Conclusions Ultrahigh-speed OCT imaging of the retina and optic nerve head at 249,000 axial scans per second is possible. The improvement of ∼5 to 10× in imaging speed over commercial spectral/Fourier domain OCT technology enables higher density raster scan protocols and improved performance of en face visualization methods. The combination of the longer wavelength and ultrahigh imaging speed enables excellent visualization of the choroid, sclera, and lamina cribrosa. PMID:18658089

The Effect of Age on Optic Nerve Axon Counts, SDOCT Scan Quality, and Peripapillary Retinal Nerve Fiber Layer Thickness Measurements in Rhesus Monkeys

PubMed Central

Fortune, Brad; Reynaud, Juan; Cull, Grant; Burgoyne, Claude F.; Wang, Lin

2014-01-01

Purpose To evaluate the effect of age on optic nerve axon counts, spectral-domain optical coherence tomography (SDOCT) scan quality, and peripapillary retinal nerve fiber layer thickness (RNFLT) measurements in healthy monkey eyes. Methods In total, 83 healthy rhesus monkeys were included in this study (age range: 1.2–26.7 years). Peripapillary RNFLT was measured by SDOCT. An automated algorithm was used to count 100% of the axons and measure their cross-sectional area in postmortem optic nerve tissue samples (N = 46). Simulation experiments were done to determine the effects of optical changes on measurements of RNFLT. An objective, fully-automated method was used to measure the diameter of the major blood vessel profiles within each SDOCT B-scan. Results Peripapillary RNFLT was negatively correlated with age in cross-sectional analysis (P < 0.01). The best-fitting linear model was RNFLT(μm) = −0.40 × age(years) + 104.5 μm (R2 = 0.1, P < 0.01). Age had very little influence on optic nerve axon count; the result of the best-fit linear model was axon count = −1364 × Age(years) + 1,210,284 (R2 < 0.01, P = 0.74). Older eyes lost the smallest diameter axons and/or axons had an increased diameter in the optic nerve of older animals. There was an inverse correlation between age and SDOCT scan quality (R = −0.65, P < 0.0001). Simulation experiments revealed that approximately 17% of the apparent cross-sectional rate of RNFLT loss is due to reduced scan quality associated with optical changes of the aging eye. Another 12% was due to thinning of the major blood vessels. Conclusions RNFLT declines by 4 μm per decade in healthy rhesus monkey eyes. This rate is approximately three times faster than loss of optic nerve axons. Approximately one-half of this difference is explained by optical degradation of the aging eye reducing SDOCT scan quality and thinning of the major blood vessels. Translational Relevance Current models used to predict retinal ganglion cell losses should be reconsidered. PMID:24932430

Pediatric and adult vision restoration after optic nerve sheath decompression for idiopathic intracranial hypertension.

PubMed

Bersani, Thomas A; Meeker, Austin R; Sismanis, Dimitrios N; Carruth, Bryant P

2016-06-01

To compare presentations of idiopathic intracranial hypertension and efficacy of optic nerve sheath decompression between adult and pediatric patients, a retrospective cohort study was completed All idiopathic intracranial hypertension patients undergoing optic nerve sheath decompression by one surgeon between 1991 and 2012 were included. Pre-operative and post-operative visual fields, visual acuity, color vision, and optic nerve appearance were compared between adult and pediatric (<18 years) populations. Outcome measures included percentage of patients with complications or requiring subsequent interventions. Thirty-one adults (46 eyes) and eleven pediatric patients (18 eyes) underwent optic nerve sheath decompression for vision loss from idiopathic intracranial hypertension. Mean deviation on visual field, visual acuity, color vision, and optic nerve appearance significantly improved across all subjects. Pre-operative mean deviation was significantly worse in children compared to adults (p=0.043); there was no difference in mean deviation post-operatively (p=0.838). Significantly more pediatric eyes (6) presented with light perception only or no light perception than adult eyes (0) (p=0.001). Pre-operative color vision performance in children (19%) was significantly worse than in adults (46%) (p=0.026). Percentage of patients with complications or requiring subsequent interventions did not differ between groups. The consistent improvement after surgery and low rate of complications suggest optic nerve sheath decompression is safe and effective in managing vision loss due to adult and pediatric idiopathic intracranial hypertension. Given the advanced pre-operative visual deficits seen in children, one might consider a higher index of suspicion in diagnosing, and earlier surgical intervention in treating pediatric idiopathic intracranial hypertension.

Coronal Axis Measurement of the Optic Nerve Sheath Diameter Using a Linear Transducer.

PubMed

Amini, Richard; Stolz, Lori A; Patanwala, Asad E; Adhikari, Srikar

2015-09-01

The true optic nerve sheath diameter cutoff value for detecting elevated intracranial pressure is variable. The variability may stem from the technique used to acquire sonographic measurements of the optic nerve sheath diameter as well as sonographic artifacts inherent to the technique. The purpose of this study was to compare the traditional visual axis technique to an infraorbital coronal axis technique for assessing the optic nerve sheath diameter using a high-frequency linear array transducer. We conducted a cross-sectional study at an academic medical center. Timed optic nerve sheath diameter measurements were obtained on both eyes of healthy adult volunteers with a 10-5-MHz broadband linear array transducer using both traditional visual axis and coronal axis techniques. Optic nerve sheath diameter measurements were obtained by 2 sonologists who graded the difficulty of each technique and were blinded to each other's measurements for each participant. A total of 42 volunteers were enrolled, yielding 84 optic nerve sheath diameter measurements. There were no significant differences in the measurements between the techniques on either eye (P = .23 [right]; P = .99 [left]). Additionally, there was no difference in the degree of difficulty obtaining the measurements between the techniques (P = .16). There was a statistically significant difference in the time required to obtain the measurements between the traditional and coronal techniques (P < .05). Infraorbital coronal axis measurements are similar to measurements obtained in the traditional visual axis. The infraorbital coronal axis technique is slightly faster to perform and is not technically challenging. © 2015 by the American Institute of Ultrasound in Medicine.

Age related optic nerve axonal loss in adult Brown Norway rats.

PubMed

Cepurna, William O; Kayton, Robert J; Johnson, Elaine C; Morrison, John C

2005-06-01

The effect of age on the number and morphology of optic nerve axons in adult Brown Norway rats (5-31 months old) (n=29) was examined using transmission electron microscopy (TEM). By manually counting every axon in areas representing 60% of the optic nerve cross-section, we found a significant negative correlation between age and axon count (R(2)=0.18, P<0.05). However, when the oldest animals were omitted, the relationship was no longer statistically significant. Simultaneously, the proportion of spontaneously degenerating axons increased at an exponential rate (R(2)=0.79, P<0.05), with significantly more degeneration in the 31-month group than in 5-month-old animals (ANOVA, P<0.05). This study demonstrates, using quantitative TEM methods, that optic nerve axonal numbers are relatively constant throughout the majority of the adult life of the Brown Norway rat, an increasingly popular strain for glaucoma research. Total axonal loss with aging is substantially less than that reported for other strains. The reduction in axonal numbers and the rate of axonal degeneration do not appear significantly altered until the last few months of life, failing to support some studies that have concluded that optic nerve axon loss in adult rats is linear. However, they do agree with other studies in the rat, and a similar study performed in non-human primate eyes, that concluded that aging changes in the optic nerve and retina follow a complex pattern. Therefore, the impact of animal age must be considered when modeling the course and pathophysiology of experimental glaucomatous optic nerve damage in rats.

[Nerve-sparing radical prostatectomy--effect and risks].

PubMed

Borre, Michael

2008-08-18

The purpose of nerve-sparing technique performing radical prostatectomy (NSRP) is to attempt to preserve the neurovascular bundle which is located posterolaterally on both sides of the prostate. The nerve-sparing technique presupposes the pre- and per operative tumour stage as well as preoperative erectile function--so as not to unnecessarily risk compromising the radicalism of the surgery. In the period 2003-2006 242 patients were radical prostatectomized (RP) at the Dept. of Urology, Aarhus University Hospital, Skejby. A total of 84 of these were offered NSRP. Data concerning erectile function preoperatively and 12 months postoperatively were compared. Likewise the postoperative tumour control following NSRP was investigated. There was a statistically significant association between NSRP and preserved potency 12 months postoperatively compared to the non-NSRP patient group. Moreover, no association between risks of positive surgical margins in patients treated with or without NSRP technique was observed. During follow up (median 39 months) the rate of biochemical recurrence was 40. Among these 8, 13 and 20% of the patients were respectively treated with bilateral-, unilateral- and non-NSRP. NSRP seems to be both a safe and effective procedure in carefully selected patients. Furthermore, the results suggest that if preoperatively potent, low- to middle-risk group patients (cT1-2a/b, Gleason score < 7 and PSA < 10 ng/mL) are potential candidates for at least unilateral NSRP.

Applications of optical coherence tomography in pediatric clinical neuroscience.

PubMed

Avery, Robert A; Rajjoub, Raneem D; Trimboli-Heidler, Carmelina; Waldman, Amy T

2015-04-01

For nearly two centuries, the ophthalmoscope has permitted examination of the retina and optic nerve-the only axons directly visualized by the physician. The retinal ganglion cells project their axons, which travel along the innermost retina to form the optic nerve, marking the beginning of the anterior visual pathway. Both the structure and function of the visual pathway are essential components of the neurologic examination as it can be involved in numerous acquired, congenital and genetic central nervous system conditions. The development of optical coherence tomography now permits the pediatric neuroscientist to visualize and quantify the optic nerve and retinal layers with unprecedented resolution. As optical coherence tomography becomes more accessible and integrated into research and clinical care, the pediatric neuroscientist may have the opportunity to utilize and/or interpret results from this device. This review describes the basic technical features of optical coherence tomography and highlights its potential clinical and research applications in pediatric clinical neuroscience including optic nerve swelling, optic neuritis, tumors of the visual pathway, vigabatrin toxicity, nystagmus, and neurodegenerative conditions. Georg Thieme Verlag KG Stuttgart · New York.

High-resolution imaging of retinal nerve fiber bundles in glaucoma using adaptive optics scanning laser ophthalmoscopy.

PubMed

Takayama, Kohei; Ooto, Sotaro; Hangai, Masanori; Ueda-Arakawa, Naoko; Yoshida, Sachiko; Akagi, Tadamichi; Ikeda, Hanako Ohashi; Nonaka, Atsushi; Hanebuchi, Masaaki; Inoue, Takashi; Yoshimura, Nagahisa

2013-05-01

To detect pathologic changes in retinal nerve fiber bundles in glaucomatous eyes seen on images obtained by adaptive optics (AO) scanning laser ophthalmoscopy (AO SLO). Prospective cross-sectional study. Twenty-eight eyes of 28 patients with open-angle glaucoma and 21 normal eyes of 21 volunteer subjects underwent a full ophthalmologic examination, visual field testing using a Humphrey Field Analyzer, fundus photography, red-free SLO imaging, spectral-domain optical coherence tomography, and imaging with an original prototype AO SLO system. The AO SLO images showed many hyperreflective bundles suggesting nerve fiber bundles. In glaucomatous eyes, the nerve fiber bundles were narrower than in normal eyes, and the nerve fiber layer thickness was correlated with the nerve fiber bundle widths on AO SLO (P < .001). In the nerve fiber layer defect area on fundus photography, the nerve fiber bundles on AO SLO were narrower compared with those in normal eyes (P < .001). At 60 degrees on the inferior temporal side of the optic disc, the nerve fiber bundle width was significantly lower, even in areas without nerve fiber layer defect, in eyes with glaucomatous eyes compared with normal eyes (P = .026). The mean deviations of each cluster in visual field testing were correlated with the corresponding nerve fiber bundle widths (P = .017). AO SLO images showed reduced nerve fiber bundle widths both in clinically normal and abnormal areas of glaucomatous eyes, and these abnormalities were associated with visual field defects, suggesting that AO SLO may be useful for detecting early nerve fiber bundle abnormalities associated with loss of visual function. Copyright © 2013 Elsevier Inc. All rights reserved.

Extraforaminal Discal Cyst as Cause of Radiculopathy.

PubMed

Mathon, Bertrand; Bienvenot, Peggy; Leclercq, Delphine

2018-01-01

We report the first extraforaminal location of a lumbar discal cyst. The patient was treated by hemilaminectomy, arthrectomy, cyst resection, and unilateral arthrodesis, achieving complete release of the nerve root. Extraforaminal lumbar discal cyst may represent an unexpected cause of sciatic pain with favorable outcome after surgical resection. Copyright © 2017 Elsevier Inc. All rights reserved.

Five-year follow-up of a patient with bilateral carotid body tumors after unilateral surgical resection.

PubMed

Demir, Tolga; Uyar, Ibrahim; Demir, Hale Bolgi; Sahin, Mazlum; Gundogdu, Gokcen

2014-10-03

Carotid body tumors are rare, highly vascularized neoplasms that arise from the paraganglia located at the carotid bifurcation. Surgery is the only curative treatment. However, treatment of bilateral carotid body tumors represents a special challenge due to potential neurovascular complications. We present the therapeutic management of a 34-year-old woman with bilateral carotid body tumors. The patient underwent surgical resection of the largest tumor. It was not possible to resect the tumor without sacrificing the ipsilateral vagal nerve. Due to unilateral vagal palsy, we decide to withhold all invasive therapy and to observe contralateral tumor growth with serial imaging studies. The patient is free of disease progression 5 years later. Treatment of bilateral CBTs should focus on preservation of the quality of life rather than on cure of the disease. In patients with previous contralateral vagal palsies, the choice between surgery and watchful waiting is a balance between the natural potential morbidity and the predictable surgical morbidity. Therefore, to avoid bilateral cranial nerve deficits, these patients may be observed until tumor growth is determined, and, if needed, treated by radiation therapy.

Fourier-domain optical coherence tomography and adaptive optics reveal nerve fiber layer loss and photoreceptor changes in a patient with optic nerve drusen.

PubMed

Choi, Stacey S; Zawadzki, Robert J; Greiner, Mark A; Werner, John S; Keltner, John L

2008-06-01

New technology allows more precise definition of structural alterations of all retinal layers although it has not been used previously in cases of optic disc drusen. Using Stratus and Fourier domain (FD) optical coherence tomography (OCT) and adaptive optics (AO) through a flood-illuminated fundus camera, we studied the retinas of a patient with long-standing optic disc drusen and acute visual loss at high altitude attributed to ischemic optic neuropathy. Stratus OCT and FD-OCT confirmed severe thinning of the retinal nerve fiber layer (RNFL). FD-OCT revealed disturbances in the photoreceptor layer heretofore not described in optic disc drusen patients. AO confirmed the FD-OCT findings in the photoreceptor layer and also showed reduced cone density at retinal locations associated with reduced visual sensitivity. Based on this study, changes occur not only in the RNFL but also in the photoreceptor layer in optic nerve drusen complicated by ischemic optic neuropathy. This is the first reported application of FD-OCT and the AO to this condition. Such new imaging technology may in the future allow monitoring of disease progression more precisely and accurately.

Estimating a structural bottle neck for eye-brain transfer of visual information from 3D-volumes of the optic nerve head from a commercial OCT device

NASA Astrophysics Data System (ADS)

Malmberg, Filip; Sandberg-Melin, Camilla; Söderberg, Per G.

2016-03-01

The aim of this project was to investigate the possibility of using OCT optic nerve head 3D information captured with a Topcon OCT 2000 device for detection of the shortest distance between the inner limit of the retina and the central limit of the pigment epithelium around the circumference of the optic nerve head. The shortest distance between these boundaries reflects the nerve fiber layer thickness and measurement of this distance is interesting for follow-up of glaucoma.

Ultrastructure of the extracellular matrix of bovine dura mater, optic nerve sheath and sclera.

PubMed

Raspanti, M; Marchini, M; Della Pasqua, V; Strocchi, R; Ruggeri, A

1992-10-01

The sclera, the outermost sheath of the optic nerve and the dura mater have been investigated histologically and ultrastructurally. Although these tissues appear very similar under the light microscope, being dense connective tissues mainly composed of collagen bundles and a limited amount of cells and elastic fibres, they exhibit subtle differences on electron microscopy. In the dura and sclera collagen appears in the form of large, nonuniform fibrils, similar to those commonly found in tendons, while in the optic nerve sheath the fibrils appear smaller and uniform, similar to those commonly observed in reticular tissues, vessel walls and skin. Freeze-fracture also reveals these fibrils to have different subfibrillar architectures, straight or helical, which correspond to 2 distinct forms of collagen fibril previously described (Raspanti et al. 1989). The other extracellular matrix components also vary with the particular collagen fibril structure. Despite their common embryological derivation, the dura mater, optic nerve sheath and sclera exhibit diversification of their extracellular matrix consistent with the mechanical loads to which these tissues are subjected. Our observations indicate that the outermost sheath of the optic nerve resembles the epineurium of peripheral nerves rather than the dura to which it is commonly likened.

Stimulation of the human auditory nerve with optical radiation

NASA Astrophysics Data System (ADS)

Fishman, Andrew; Winkler, Piotr; Mierzwinski, Jozef; Beuth, Wojciech; Izzo Matic, Agnella; Siedlecki, Zygmunt; Teudt, Ingo; Maier, Hannes; Richter, Claus-Peter

2009-02-01

A novel, spatially selective method to stimulate cranial nerves has been proposed: contact free stimulation with optical radiation. The radiation source is an infrared pulsed laser. The Case Report is the first report ever that shows that optical stimulation of the auditory nerve is possible in the human. The ethical approach to conduct any measurements or tests in humans requires efficacy and safety studies in animals, which have been conducted in gerbils. This report represents the first step in a translational research project to initiate a paradigm shift in neural interfaces. A patient was selected who required surgical removal of a large meningioma angiomatum WHO I by a planned transcochlear approach. Prior to cochlear ablation by drilling and subsequent tumor resection, the cochlear nerve was stimulated with a pulsed infrared laser at low radiation energies. Stimulation with optical radiation evoked compound action potentials from the human auditory nerve. Stimulation of the auditory nerve with infrared laser pulses is possible in the human inner ear. The finding is an important step for translating results from animal experiments to human and furthers the development of a novel interface that uses optical radiation to stimulate neurons. Additional measurements are required to optimize the stimulation parameters.

Patterns of intraocular pressure elevation after aqueous humor outflow obstruction in rats.

PubMed

Jia, L; Cepurna, W O; Johnson, E C; Morrison, J C

2000-05-01

To determine the diural intraocular pressure (IOP) response of Brown Norway rat eyes after sclerosis of the aqueous humor outflow pathways and its relationship to optic nerve damage. Hypertonic saline was injected into a single episcleral vein in 17 animals and awake IOP measured in both the light and dark phases of the circadian cycle for 34 days. Mean IOP for light and dark phases during the experimental period were compared with the respective pressures of the uninjected fellow eyes. Optic nerve cross sections from each nerve were graded for injury by five independent masked observers. For fellow eyes, mean light- and dark-phase IOP was 21 +/- 1 and 31 +/- 1 mm Hg, respectively. For four experimental eyes, mean IOPs for both phases were not altered. Six eyes demonstrated significant mean IOP elevations only during the dark phase. Of these, five showed persistent, large circadian oscillations, and four had partial optic nerve lesions. The remaining seven eyes experienced significant IOP elevations during both phases, and all had extensive optic nerve damage. Episcleral vein injection of hypertonic saline is more likely to increase IOP during the dark phase than the light. This is consistent with aqueous outflow obstruction superimposed on a circadian rhythm of aqueous humor production. Because these periodic IOP elevations produced optic nerve lesions, both light- and dark-phase IOP determinations are necessary for accurate correlation of IOP history to optic nerve damage in animals housed in a light- dark environment.

Delayed Unilateral Soft Palate Palsy without Vocal Cord Involvement after Microvascular Decompression for Hemifacial Spasm

PubMed Central

Park, Jae Han; Jo, Kyung Il

2013-01-01

Microvascular decompression is a very effective and relatively safe surgical modality in the treatment of hemifacial spasm. But rare debilitating complications have been reported such as cranial nerve dysfunctions. We have experienced a very rare case of unilateral soft palate palsy without the involvement of vocal cord following microvascular decompression. A 33-year-old female presented to our out-patient clinic with a history of left hemifacial spasm for 5 years. On postoperative 5th day, patient started to exhibit hoarsness with swallowing difficulty. Symptoms persisted despite rehabilitation. Various laboratory work up with magnetic resonance image showed no abnormal lesions. Two years after surgery patient showed complete recovery of unitaleral soft palate palsy. Various etiologies of unilateral soft palate palsy are reviewed as the treatment and prognosis differs greatly on the cause. Although rare, it is important to keep in mind that such complication could occur after microvascular decompression. PMID:24003372

Lost in the jungle: new hurdles for optic nerve axon regeneration.

PubMed

Pernet, Vincent; Schwab, Martin E

2014-07-01

The poor regenerative capacity of injured central nervous system (CNS) axons leads to permanent neurological deficits after brain, spinal cord, or optic nerve lesions. In the optic nerve, recent studies showed that stimulation of the cytokine or mammalian target of rapamycin (mTOR) signaling pathways potently enhances sprouting and regeneration of injured retinal ganglion cell axons in adult mice, but does not allow the majority of axons to reach their main cerebral targets. New analyses have revealed axon navigation defects in the optic nerve and at the optic chiasm under conditions of strong growth stimulation. We propose that a balanced growth stimulatory treatment will have to be combined with guidance factors and suppression of local growth inhibitory factors to obtain the full regeneration of long CNS axonal tracts. Copyright © 2014 Elsevier Ltd. All rights reserved.

A study of axonal degeneration in the optic nerves of aging mice

NASA Technical Reports Server (NTRS)

Johnson, J. E., Jr.; Philpott, D. E.; Miquel, J.

1978-01-01

The optic nerves of C57BL/6J mice ranging from 3 to 30 months were examined by electron microscopy. At all ages investigated, optic nerve axons contained enlarged mitochondria with abnormal cristae. With increasing age, a large number of necrotic axons were observed and were in the process of being phagocytized. The abnormal mitochondria may represent preliminary changes that eventually lead to necrosis of the axon.

Sodium channels in axons and glial cells of the optic nerve of Necturus maculosa.

PubMed

Tang, C M; Strichartz, G R; Orkand, R K

1979-11-01

Experiments investigating both the binding of radioactively labelled saxitoxin (STX) and the electrophysiological response to drugs that increase the sodium permeability of excitable membranes were conducted in an effort to detect sodium channels in glial cells of the optic nerve of Necturus maculosa, the mudpuppy. Glial cells in nerves from chronically enucleated animals, which lack optic nerve axons, show no saturable uptake of STX whereas a saturable uptake is clearly present in normal optic nerves. The normal nerve is depolarized by aconitine, batrachotoxin, and veratridine (10(-6)-10(-5) M), whereas the all-glial preparation is only depolarized by veratridine and at concentrations greater than 10(-3) M. Unlike the depolarization caused by veratridine in normal nerves, the response in the all-glial tissue is not blocked by tetrodotoxin nor enhanced by scorpion venom (Leiurus quinquestriatus). In glial cells of the normal nerve, where axons are also present, the addition of 10(-5) M veratridine does lead to a transient depolarization; however, it is much briefer than the axonal response to veratridine in this same tissue. This glial response to veratridine could be caused by the efflux of K+ from the drug-depolarized axons, and is similar to the glial response to extracellular K+ accumulation resulting from action potentials in the axon.

Sodium channels in axons and glial cells of the optic nerve of Necturus maculosa

PubMed Central

1979-01-01

Experiments investigating both the binding of radioactively labelled saxitoxin (STX) and the electrophysiological response to drugs that increase the sodium permeability of excitable membranes were conducted in an effort to detect sodium channels in glial cells of the optic nerve of Necturus maculosa, the mudpuppy. Glial cells in nerves from chronically enucleated animals, which lack optic nerve axons, show no saturable uptake of STX whereas a saturable uptake is clearly present in normal optic nerves. The normal nerve is depolarized by aconitine, batrachotoxin, and veratridine (10(-6)-10(-5) M), whereas the all-glial preparation is only depolarized by veratridine and at concentrations greater than 10(-3) M. Unlike the depolarization caused by veratridine in normal nerves, the response in the all-glial tissue is not blocked by tetrodotoxin nor enhanced by scorpion venom (Leiurus quinquestriatus). In glial cells of the normal nerve, where axons are also present, the addition of 10(-5) M veratridine does lead to a transient depolarization; however, it is much briefer than the axonal response to veratridine in this same tissue. This glial response to veratridine could be caused by the efflux of K+ from the drug- depolarized axons, and is similar to the glial response to extracellular K+ accumulation resulting from action potentials in the axon. PMID:512633

Analysis of the Istanbul Forensic Medicine Institute expert decisions on recurrent laryngeal nerve injuries due to thyroidectomy between 2008-2012.

PubMed

Karakaya, M Arif; Koç, Okay; Ekiz, Feza; Ağaçhan, A Feran; Göret, Nuri Emrah

2016-01-01

The aim of this study was to evaluate the approach of Forensic Medicine Institution for recurrent laryngeal nerve injuries. In addition, parameters that were taken into consideration by Forensic Medicine Institution in the differentiation of complication and malpractice were evaluated. The files of 38 patients, with recurrent laryngeal nerve injury following thyroidectomy, that were referred to Istanbul Forensic Medicine Institute with request of expert opinion between 2008-2012 were retrospectively investigated. Data regarding expert decisions, age, gender, diagnosis, hospital type, preoperative vocal cord examination, intraoperative nerve monitoring (IONM), identification of nerve injury during operation, repair of nerve during operation, and type of injury were assessed. Surgeons were found to be faulty in all files with bilateral nerve injury, however, one-sided injury files were considered as a medical complication. Twenty-one (55.2%) patients were female, and 17 (44.8%) were male, with a mean age of 35,8 in women, and 34,1 in men. None of these patients had undergone preoperative vocal cord assessment. The recurrent laryngeal nerve was intraoperatively identified in 21 (55.2%) patients, while it was not seen in 17 (44.8%) patients. IONM was not applied in any patients. There was no attempt for nerve repair during any operation. Nineteen patients had unilateral, and 19 patients had bilateral nerve damage. Bilateral recurrent laryngeal nerve injuries are considered as malpractice, when imaging or pathology reports fail to state a cause for difficulty in nerve identification.

Comparison of Inner Ear Contrast Enhancement among Patients with Unilateral Inner Ear Symptoms in MR Images Obtained 10 Minutes and 4 Hours after Gadolinium Injection.

PubMed

Kim, T Y; Park, D W; Lee, Y J; Lee, J Y; Lee, S H; Chung, J H; Lee, S

2015-12-01

Recently 4-hour delayed-enhanced 3D-FLAIR MR imaging has been used in pathophysiologic analysis of the inner ear in many auditory diseases, including sudden sensorineural hearing loss, but comparison among different time points is not clear in patients with unilateral inner ear symptoms. We compared the signal-intensity ratios of the inner ears in patients with unilateral inner ear symptoms on 10-minute delayed-enhanced and 4-hour delayed-enhanced 3D-FLAIR MR images after IV gadolinium injection. The 10-minute delayed-enhanced and 4-hour delayed-enhanced 3D-FLAIR MR images were retrospectively analyzed. Signal-intensity ratios between the cerebellum and inner ear structures, such as the cochleae, vestibules, and vestibulocochlear nerve were assessed. Multiple comparisons were performed. Signal-intensity ratios of the affected cochleae, vestibules, and vestibulocochlear nerve were higher than those of unaffected sides in both 10-minute delayed-enhanced and 4-hour delayed-enhanced images. At the affected side, signal-intensity ratios of the vestibulocochlear nerve were higher in patients with nonsudden sensorineural hearing loss than in those with sudden sensorineural hearing loss on both 10-minute delayed-enhanced and 4-hour delayed-enhanced images. The signal-intensity ratios of some affected inner ear structures were higher than those of the unaffected sides in a group of 30 patients with sudden sensorineural hearing loss and 20 patients with nonsudden sensorineural hearing loss on 10-minute delayed-enhanced and 4-hour delayed-enhanced images. Signal-intensity ratios of the inner ear show statistically significant increases in many diseases, especially neuritis, in 10-minute delayed-enhanced and 4-hour delayed-enhanced images. The 4-hour delayed-enhanced images may be superior in neural inflammatory-dominant conditions, while 10-minute delayed-enhanced images may be superior in neural noninflammatory-dominant conditions. © 2015 by American Journal of Neuroradiology.

Radiation-induced ocular motor cranial nerve palsies in patients with pituitary tumor.

PubMed

Vaphiades, Michael S; Spencer, Sharon A; Riley, Kristen; Francis, Courtney; Deitz, Luke; Kline, Lanning B

2011-09-01

Radiation therapy is often used in the treatment of pituitary tumor. Diplopia due to radiation damage to the ocular motor cranial nerves has been infrequently reported as a complication in this clinical setting. Retrospective case series of 6 patients (3 men and 3 women) with pituitary adenoma, all of whom developed diplopia following transsphenoidal resection of pituitary adenoma with subsequent radiation therapy. None had evidence of tumor involvement of the cavernous sinus. Five patients developed sixth nerve palsies, 3 unilateral and 2 bilateral, and in 1 patient, a sixth nerve palsy was preceded by a fourth cranial nerve palsy. One patient developed third nerve palsy. Five of the 6 patients had a growth hormone-secreting pituitary tumor with acromegaly. Following transsphenoidal surgery in all 6 patients (2 had 2 surgeries), 4 had 2 radiation treatments consisting of either radiosurgery (2 patients) or external beam radiation followed by radiosurgery (2 patients). Patients with pituitary tumors treated multiple times with various forms of radiation therapy are at risk to sustain ocular motor cranial nerve injury. The prevalence of acromegalic patients in this study reflects an aggressive attempt to salvage patients with recalcitrant growth hormone elevation and may place the patient at a greater risk for ocular motor cranial nerve damage.

Optical Coherence Tomography in Glaucoma

NASA Astrophysics Data System (ADS)

Berisha, Fatmire; Hoffmann, Esther M.; Pfeiffer, Norbert

Retinal nerve fiber layer (RNFL) thinning and optic nerve head cupping are key diagnostic features of glaucomatous optic neuropathy. The higher resolution of the recently introduced SD-OCT offers enhanced visualization and improved segmentation of the retinal layers, providing a higher accuracy in identification of subtle changes of the optic disc and RNFL thinning associated with glaucoma.

Retinal nerve fiber layer thickness measured with optical coherence tomography is related to visual function in glaucomatous eyes.

PubMed

El Beltagi, Tarek A; Bowd, Christopher; Boden, Catherine; Amini, Payam; Sample, Pamela A; Zangwill, Linda M; Weinreb, Robert N

2003-11-01

To determine the relationship between areas of glaucomatous retinal nerve fiber layer thinning identified by optical coherence tomography and areas of decreased visual field sensitivity identified by standard automated perimetry in glaucomatous eyes. Retrospective observational case series. Forty-three patients with glaucomatous optic neuropathy identified by optic disc stereo photographs and standard automated perimetry mean deviations >-8 dB were included. Participants were imaged with optical coherence tomography within 6 months of reliable standard automated perimetry testing. The location and number of optical coherence tomography clock hour retinal nerve fiber layer thickness measures outside normal limits were compared with the location and number of standard automated perimetry visual field zones outside normal limits. Further, the relationship between the deviation from normal optical coherence tomography-measured retinal nerve fiber layer thickness at each clock hour and the average pattern deviation in each visual field zone was examined by using linear regression (R(2)). The retinal nerve fiber layer areas most frequently outside normal limits were the inferior and inferior temporal regions. The least sensitive visual field zones were in the superior hemifield. Linear regression results (R(2)) showed that deviation from the normal retinal nerve fiber layer thickness at optical coherence tomography clock hour positions 6 o'clock, 7 o'clock, and 8 o'clock (inferior and inferior temporal) was best correlated with standard automated perimetry pattern deviation in visual field zones corresponding to the superior arcuate and nasal step regions (R(2) range, 0.34-0.57). These associations were much stronger than those between clock hour position 6 o'clock and the visual field zone corresponding to the inferior nasal step region (R(2) = 0.01). Localized retinal nerve fiber layer thinning, measured by optical coherence tomography, is topographically related to decreased localized standard automated perimetry sensitivity in glaucoma patients.

Study on the deformations of the lamina cribrosa during glaucoma.

PubMed

Tian, Hanjing; Li, Long; Song, Fan

2017-06-01

The lamina cribrosa is the primary site of optic nerve injury during glaucoma, and its deformations induced by elevated intraocular pressure are associated directly with the optic nerve injury and visual field defect. However, the deformations in a living body have been poorly understood yet so far. It is because that integral observation and precise measurement of the deformations in vivo are now almost impossible in the clinical diagnosis and treatment of glaucoma. In the present study, a new mechanical model of the lamina cribrosa is presented by using Reissner's thin plate theory. This model accurately displays the stress and deformation states in the lamina cribrosa under elevated intraocular pressure, in which the shear deformation is not presented by the previous models, however, is demonstrated to play a key role in the optic nerve injury. Further, the deformations of the structures, involving the optic nerve channels and the laminar sheets in the lamina cribrosa, are first investigated in detail. For example, the dislocation of the laminar sheets reaches 18.6μm under the intraocular pressure of 40mmHg, which is large enough to damage the optic nerve axons. The results here confirm some previously proposed clinical speculations on the deformations of the pore shape in the lamina cribrosa under elevated intraocular pressure during glaucoma. Finally, some essentially clinical questions existed during glaucoma, such as the pathological mechanism of the open-angle glaucoma with normal intraocular pressure, are discussed. The present study is beneficial to deeply understanding the optic nerve injury during glaucoma. The lamina cribrosa is the primary site of the optic nerve injury induced by elevated intraocular pressure during glaucoma. Under high intraocular pressure, the optic nerve channel near to the periphery of the lamina cribrosa (Channel A) is deformed to become into a tortuous elliptical horn from a straight cylinder, while the optic nerve channel near to the center of the lamina cribrosa (Channel B) is deformed to become into a straight horn from a straight cylinder. These deformations cause both the axoplasm flow obstacle in the axon fibers and the blocked blood flow in the capillaries which pass through the channels, and trigger the visual field defect during glaucoma. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Evolution of an Astrocytic Hamartoma of the Optic Nerve Head in a Patient with Retinitis Pigmentosa – Photographic Documentation over 2 Years of Follow-Up

PubMed Central

Loukianou, Eleni; Kisma, Nacima; Pal, Bishwanathan

2011-01-01

Aim To report photographically the evolution of an astrocytic hamartoma of the left optic nerve head over a 2-year follow-up in a patient with retinitis pigmentosa. Methods A 14-year-old boy was seen in the medical retina clinic with a 3-year history of night blindness. Best corrected visual acuity was 6/18 in both eyes. Colour vision was normal in both eyes and confrontation fields showed peripheral constriction. Fundus examination revealed bone spicule pigmentary changes at the retinal mid periphery typical of retinitis pigmentosa and superficial globules at the margins of both optic nerve heads. Electrodiagnostic tests confirmed moderately severe rod cone dystrophy with macular involvement bilaterally. Results Two years later, the ocular examination was unchanged except for the appearance of the optic nerve head lesion in the left eye. There was an increase in the size of the lesion which was diagnosed as an astrocytic hamartoma. Further investigations were recommended to exclude neurofibromatosis and tuberous sclerosis. Conclusion Astrocytic hamartomas of the optic nerve head and optic nerve head drusen have both been described in patients with retinitis pigmentosa. They can be a diagnostic dilemma although drusen are more common (10%). To differentiate these two entities it is very important to document any growth during the follow-up period which is suggestive of astrocytic hamartoma rather than optic disc drusen. PMID:21347192

Efficacy and safety of acute injection laryngoplasty for vocal cord paralysis following thoracic surgery.

PubMed

Graboyes, Evan M; Bradley, Joseph P; Meyers, Bryan F; Nussenbaum, Brian

2011-11-01

The primary objective of this study was to evaluate the effectiveness and safety of injection laryngoplasty using a temporary injectable agent in the acute setting for patients with unilateral vocal cord paralysis following thoracic surgical procedures. Retrospective consecutive case series in an academic institution. Inclusion criteria included patients acutely treated with injection laryngoplasty from January 1, 2006, to March 31, 2010, for a unilateral vocal cord paralysis that occurred after a thoracic surgical procedure (N = 20). All patients were injected with Radiesse Voice Gel using microlaryngoscopy technique. The mean time to vocal cord injection from the time of thoracic surgery was 4.5 days. There was one operative-related complication of intraoperative bile reflux that caused a pneumonitis. Ninety percent of patients were recommended for strict nothing by mouth prior to injection. Of these, 94% were allowed an oral diet following injection, and 67% tolerated a regular diet. None of the patients required subsequent procedures for aspiration or dysphagia, and 25% required further intervention after discharge for persistent dysphonia. Patients with a known nerve transection had a higher rate of dysphonia requiring further surgical procedures than those who did not have a known nerve transection. Acute treatment of thoracic surgery-related unilateral vocal cord paralysis with injection laryngoplasty appears safe and effective at preventing postoperative aspiration pneumonia and improves swallowing function to allow resumption of an oral diet. A single injection is often the only required treatment. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

In Vivo Imaging of Glial Activation after Unilateral Labyrinthectomy in the Rat: A [18F]GE180-PET Study.

PubMed

Zwergal, Andreas; Günther, Lisa; Brendel, Matthias; Beck, Roswitha; Lindner, Simon; Xiong, Guoming; Eilles, Eva; Unterrainer, Marcus; Albert, Nathalie Lisa; Becker-Bense, Sandra; Brandt, Thomas; Ziegler, Sibylle; la Fougère, Christian; Dieterich, Marianne; Bartenstein, Peter

2017-01-01

The functional relevance of reactive gliosis for recovery from acute unilateral vestibulopathy is unknown. In the present study, glial activation was visualized in vivo by [ 18 F]GE180-PET in a rat model of unilateral labyrinthectomy (UL) and compared to behavioral vestibular compensation (VC) overtime. 14 Sprague-Dawley rats underwent a UL by transtympanic injection of bupivacaine/arsenilate, 14 rats a SHAM UL (injection of normal saline). Glial activation was depicted with [ 18 F]GE180-PET and ex vivo autoradiography at baseline and 7, 15, 30 days after UL/SHAM UL. Postural asymmetry and nystagmus were registered at 1, 2, 3, 7, 15, 30 days after UL/SHAM UL. Signs of vestibular imbalance were found only after UL, which significantly decreased until days 15 and 30. In parallel, [ 18 F]GE180-PET and ex vivo autoradiography depicted glial activation in the ipsilesional vestibular nerve and nucleus on days 7 and 15 after UL. Correlation analysis revealed a strong negative association of [ 18 F]GE180 uptake in the ipsilesional vestibular nucleus on day 7 with the rate of postural recovery ( R  = -0.90, p  < 0.001), suggesting that glial activation accelerates VC. In conclusion, glial activation takes place in the ipsilesional vestibular nerve and nucleus within the first 30 days after UL in the rat and can be visualized in vivo by [ 18 F]GE180-PET.

In Vivo Imaging of Glial Activation after Unilateral Labyrinthectomy in the Rat: A [18F]GE180-PET Study

PubMed Central

Zwergal, Andreas; Günther, Lisa; Brendel, Matthias; Beck, Roswitha; Lindner, Simon; Xiong, Guoming; Eilles, Eva; Unterrainer, Marcus; Albert, Nathalie Lisa; Becker-Bense, Sandra; Brandt, Thomas; Ziegler, Sibylle; la Fougère, Christian; Dieterich, Marianne; Bartenstein, Peter

2017-01-01

The functional relevance of reactive gliosis for recovery from acute unilateral vestibulopathy is unknown. In the present study, glial activation was visualized in vivo by [18F]GE180-PET in a rat model of unilateral labyrinthectomy (UL) and compared to behavioral vestibular compensation (VC) overtime. 14 Sprague-Dawley rats underwent a UL by transtympanic injection of bupivacaine/arsenilate, 14 rats a SHAM UL (injection of normal saline). Glial activation was depicted with [18F]GE180-PET and ex vivo autoradiography at baseline and 7, 15, 30 days after UL/SHAM UL. Postural asymmetry and nystagmus were registered at 1, 2, 3, 7, 15, 30 days after UL/SHAM UL. Signs of vestibular imbalance were found only after UL, which significantly decreased until days 15 and 30. In parallel, [18F]GE180-PET and ex vivo autoradiography depicted glial activation in the ipsilesional vestibular nerve and nucleus on days 7 and 15 after UL. Correlation analysis revealed a strong negative association of [18F]GE180 uptake in the ipsilesional vestibular nucleus on day 7 with the rate of postural recovery (R = −0.90, p < 0.001), suggesting that glial activation accelerates VC. In conclusion, glial activation takes place in the ipsilesional vestibular nerve and nucleus within the first 30 days after UL in the rat and can be visualized in vivo by [18F]GE180-PET. PMID:29312111

Effect of race, age, and axial length on optic nerve head parameters and retinal nerve fiber layer thickness measured by Cirrus HD-OCT.

PubMed

Knight, O'Rese J; Girkin, Christopher A; Budenz, Donald L; Durbin, Mary K; Feuer, William J

2012-03-01

To determine the effect of race, demographic, and ocular variables on optic nerve head and retinal nerve fiber layer (RNFL) thickness measurements using spectral-domain optical coherence tomography. In a cross-sectional observational study, 284 normal subjects aged 18 to 84 years were evaluated at 7 sites using Cirrus HD-OCT. Disc area, rim area, average cup-disc ratio, vertical cup-disc ratio, cup volume, and average, temporal, superior, nasal, and inferior RNFL thicknesses were calculated. The main outcome measures were associations between Cirrus HD-OCT optic nerve head and RNFL measurements and age, sex, and race. The 284 subjects self-identified as being of European (122), Chinese (63), African (51), or Hispanic (35) descent. After adjusting for the effect of age, there was a statistically significant difference among racial groups for all optic nerve head and RNFL parameters (all P ≤ .005) except rim area (P = .22). Rim area, average cup-disc ratio, vertical cup-disc ratio, and cup volume were moderately associated with disc area (r(2) = 0.15, 0.33, 0.33, and 0.37, respectively). After a linear adjustment for disc area, there was no statistically significant difference among racial groups for any optic nerve head parameter. Individuals of European descent had thinner RNFL measurements except in the temporal quadrant. There are racial differences in optic disc area, average cup-disc ratio, vertical cup-disc ratio, cup volume, and RNFL thickness as measured by Cirrus HD-OCT. These differences should be considered when using Cirrus HD-OCT to assess for glaucomatous damage in differing population groups.

Effect of Race, Age, and Axial Length on Optic Nerve Head Parameters and Retinal Nerve Fiber Layer Thickness Measured by Cirrus HD-OCT

PubMed Central

Knight, O’Rese J.; Girkin, Christopher A.; Budenz, Donald L.; Durbin, Mary K.; Feuer, William J.

2017-01-01

Objective To determine the effect of race, demographic, and ocular variables on optic nerve head and retinal nerve fiber layer (RNFL) thickness measurements using spectral-domain optical coherence tomography. Methods In a cross-sectional observational study, 284 normal subjects aged 18 to 84 years were evaluated at 7 sites using Cirrus HD-OCT. Disc area, rim area, average cup-disc ratio, vertical cup-disc ratio, cup volume, and average, temporal, superior, nasal, and inferior RNFL thicknesses were calculated. The main outcome measures were associations between Cirrus HD-OCT optic nerve head and RNFL measurements and age, sex, and race. Results The 284 subjects self-identified as being of European (122), Chinese (63), African (51), or Hispanic (35) descent. After adjusting for the effect of age, there was a statistically significant difference among racial groups for all optic nerve head and RNFL parameters (all P≤.005) except rim area (P=.22). Rim area, average cup-disc ratio, vertical cup-disc ratio, and cup volume were moderately associated with disc area (r2=0.15, 0.33, 0.33, and 0.37, respectively). After a linear adjustment for disc area, there was no statistically significant difference among racial groups for any optic nerve head parameter. Individuals of European descent had thinner RNFL measurements except in the temporal quadrant. Conclusions There are racial differences in optic disc area, average cup-disc ratio, vertical cup-disc ratio, cup volume, and RNFL thickness as measured by Cirrus HD-OCT. These differences should be considered when using Cirrus HD-OCT to assess for glaucomatous damage in differing population groups. PMID:22411660

Imaging of macrophage dynamics with optical coherence tomography in anterior ischemic optic neuropathy.

PubMed

Kokona, Despina; Häner, Nathanael U; Ebneter, Andreas; Zinkernagel, Martin S

2017-01-01

Anterior ischemic optic neuropathy (AION) is a relatively common cause of visual loss and results from hypoperfusion of the small arteries of the anterior portion of the optic nerve. AION is the leading cause of sudden optic nerve related vision loss with approximately 10 cases per 100'000 in the population over 50 years. To date there is no established treatment for AION and therefore a better understanding of the events occurring at the level of the optic nerve head (ONH) would be important to design future therapeutic strategies. The optical properties of the eye allow imaging of the optic nerve in vivo, which is a part of the CNS, during ischemia. Experimentally laser induced optic neuropathy (eLiON) displays similar anatomical features as anterior ischemic optic neuropathy in humans. After laser induced optic neuropathy we show that hyperreflective dots in optical coherence tomography correspond to mononuclear cells in histology. Using fluorescence-activated flow cytometry (FACS) we found these cells to peak one week after eLiON. These observations were translated to OCT findings in patients with AION, where similar dynamics of hyperreflective dots at the ONH were identified. Our data suggests that activated macrophages can be identified as hyperreflective dots in OCT. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

In vivo optical microscopy of peripheral nerve myelination with polarization sensitive-optical coherence tomography

PubMed Central

Henry, Francis P.; Wang, Yan; Rodriguez, Carissa L. R.; Randolph, Mark A.; Rust, Esther A. Z.; Winograd, Jonathan M.; de Boer, Johannes F.; Park, B. Hyle

2015-01-01

Abstract. Assessing nerve integrity and myelination after injury is necessary to provide insight for treatment strategies aimed at restoring neuromuscular function. Currently, this is largely done with electrical analysis, which lacks direct quantitative information. In vivo optical imaging with sufficient imaging depth and resolution could be used to assess the nerve microarchitecture. In this study, we examine the use of polarization sensitive-optical coherence tomography (PS-OCT) to quantitatively assess the sciatic nerve microenvironment through measurements of birefringence after applying a nerve crush injury in a rat model. Initial loss of function and subsequent recovery were demonstrated by calculating the sciatic function index (SFI). We found that the PS-OCT phase retardation slope, which is proportional to birefringence, increased monotonically with the SFI. Additionally, histomorphometric analysis of the myelin thickness and g-ratio shows that the PS-OCT slope is a good indicator of myelin health and recovery after injury. These results demonstrate that PS-OCT is capable of providing nondestructive and quantitative assessment of nerve health after injury and shows promise for continued use both clinically and experimentally in neuroscience. PMID:25858593

In vivo optical microscopy of peripheral nerve myelination with polarization sensitive-optical coherence tomography.

PubMed

Henry, Francis P; Wang, Yan; Rodriguez, Carissa L R; Randolph, Mark A; Rust, Esther A Z; Winograd, Jonathan M; de Boer, Johannes F; Park, B Hyle

2015-04-01

Assessing nerve integrity and myelination after injury is necessary to provide insight for treatment strategies aimed at restoring neuromuscular function. Currently, this is largely done with electrical analysis, which lacks direct quantitative information. In vivo optical imaging with sufficient imaging depth and resolution could be used to assess the nerve microarchitecture. In this study, we examine the use of polarization sensitive-optical coherence tomography (PS-OCT) to quantitatively assess the sciatic nerve microenvironment through measurements of birefringence after applying a nerve crush injury in a rat model. Initial loss of function and subsequent recovery were demonstrated by calculating the sciatic function index (SFI). We found that the PS-OCT phase retardation slope, which is proportional to birefringence, increased monotonically with the SFI. Additionally, histomorphometric analysis of the myelin thickness and g-ratio shows that the PS-OCT slope is a good indicator of myelin health and recovery after injury. These results demonstrate that PS-OCT is capable of providing nondestructive and quantitative assessment of nerve health after injury and shows promise for continued use both clinically and experimentally in neuroscience.

Novel Retinal Lesion in Ebola Survivors, Sierra Leone, 2016

PubMed Central

Scott, Janet T.; Baxter, Julia M.; Parkes, Craig K.; Dwivedi, Rahul; Czanner, Gabriela; Vandy, Matthew J.; Momorie, Fayiah; Fornah, Alimamy D.; Komba, Patrick; Richards, Jade; Sahr, Foday; Beare, Nicholas A.V.; Semple, Malcolm G.

2017-01-01

We conducted a case–control study in Freetown, Sierra Leone, to investigate ocular signs in Ebola virus disease (EVD) survivors. A total of 82 EVD survivors with ocular symptoms and 105 controls from asymptomatic civilian and military personnel and symptomatic eye clinic attendees underwent ophthalmic examination, including widefield retinal imaging. Snellen visual acuity was <6/7.5 in 75.6% (97.5% CI 63%–85.7%) of EVD survivors and 75.5% (97.5% CI 59.1%–87.9%) of controls. Unilateral white cataracts were present in 7.4% (97.5% CI 2.4%–16.7%) of EVD survivors and no controls. Aqueous humor from 2 EVD survivors with cataract but no anterior chamber inflammation were PCR-negative for Zaire Ebola virus, permitting cataract surgery. A novel retinal lesion following the anatomic distribution of the optic nerve axons occurred in 14.6% (97.5% CI 7.1%–25.6%) of EVD survivors and no controls, suggesting neuronal transmission as a route of ocular entry. PMID:28628441

Novel Retinal Lesion in Ebola Survivors, Sierra Leone, 2016.

PubMed

Steptoe, Paul J; Scott, Janet T; Baxter, Julia M; Parkes, Craig K; Dwivedi, Rahul; Czanner, Gabriela; Vandy, Matthew J; Momorie, Fayiah; Fornah, Alimamy D; Komba, Patrick; Richards, Jade; Sahr, Foday; Beare, Nicholas A V; Semple, Malcolm G

2017-07-01

We conducted a case-control study in Freetown, Sierra Leone, to investigate ocular signs in Ebola virus disease (EVD) survivors. A total of 82 EVD survivors with ocular symptoms and 105 controls from asymptomatic civilian and military personnel and symptomatic eye clinic attendees underwent ophthalmic examination, including widefield retinal imaging. Snellen visual acuity was <6/7.5 in 75.6% (97.5% CI 63%-85.7%) of EVD survivors and 75.5% (97.5% CI 59.1%-87.9%) of controls. Unilateral white cataracts were present in 7.4% (97.5% CI 2.4%-16.7%) of EVD survivors and no controls. Aqueous humor from 2 EVD survivors with cataract but no anterior chamber inflammation were PCR-negative for Zaire Ebola virus, permitting cataract surgery. A novel retinal lesion following the anatomic distribution of the optic nerve axons occurred in 14.6% (97.5% CI 7.1%-25.6%) of EVD survivors and no controls, suggesting neuronal transmission as a route of ocular entry.

A Rodent Model of Dynamic Facial Reanimation Using Functional Electrical Stimulation

PubMed Central

Attiah, Mark A.; de Vries, Julius; Richardson, Andrew G.; Lucas, Timothy H.

2017-01-01

Facial paralysis can be a devastating condition, causing disfiguring facial droop, slurred speech, eye dryness, scarring and blindness. This study investigated the utility of closed-loop functional electric stimulation (FES) for reanimating paralyzed facial muscles in a quantitative rodent model. The right buccal and marginal mandibular branches of the rat facial nerve were transected for selective, unilateral paralysis of whisker muscles. Microwire electrodes were implanted bilaterally into the facial musculature for FES and electromyographic (EMG) recording. With the rats awake and head-fixed, whisker trajectories were tracked bilaterally with optical micrometers. First, the relationship between EMG and volitional whisker movement was quantified on the intact side of the face. Second, the effect of FES on whisker trajectories was quantified on the paralyzed side. Third, closed-loop experiments were performed in which the EMG signal on the intact side triggered FES on the paralyzed side to restore symmetric whisking. The results demonstrate a novel in vivo platform for developing control strategies for neuromuscular facial prostheses. PMID:28424583

High resolution transbulbar sonography in children with suspicion of increased intracranial pressure.

PubMed

Steinborn, Marc; Friedmann, Melanie; Makowski, Christine; Hahn, Helmut; Hapfelmeier, Alexander; Juenger, Hendrik

2016-04-01

To evaluate the accuracy of high resolution transbulbar sonography for the estimation of intracranial pressure (ICP) in children. In children and adolescents with acute neurologic symptoms of various origin, transbulbar sonography was performed. Besides measurement of the optic nerve sheath diameter (ONSD), the ultrastructure of the subarachnoid space of the optic nerve sheath was evaluated. The results of transbulbar sonography were correlated with clinical data based on cross-sectional imaging, ICP measurement, and ophthalmologic examination. Eighty-one patients (age 3-17.8 years, mean 11.7 years) were included. In 25 children, cross-sectional imaging and ICP measurement revealed increased intracranial pressure. The mean ONSD was 6.85 ± 0.81 mm. Twenty patients (20/25, 80 %) had a microcystic appearance of the subarachnoid space of the optic nerve. In 56 children without evidence of increased intracranial pressure, the mean ONSD was 5.77 ± 0.48 mm. Forty-nine patients (49/56, 87.5 %) had a normal homogenous appearance of the subarachnoid space. The ONSD in children with increased intracranial pressure was significantly higher than in patients without (p < 0.001). High resolution transbulbar sonography of the optic nerve is a useful technique for the rapid and non-invasive estimation of intracranial pressure in children. Besides measurement of the optic nerve sheath diameter, evaluation of the ultrastructure of the subarachnoid space of the optic nerve is a helpful parameter.

Expanding the limits of endoscopic intraorbital tumor resection using 3-dimensional reconstruction.

PubMed

Gregorio, Luciano Lobato; Busaba, Nicolas Y; Miyake, Marcel M; Freitag, Suzanne K; Bleier, Benjamin S

2017-12-26

Endoscopic orbital surgery is a nascent field and new tools are required to assist with surgical planning and to ascertain the limits of the tumor resectability. We purpose to utilize three-dimensional radiographic reconstruction to define the theoretical lateral limit of endoscopic resectability of primary orbital tumors and to apply these boundary conditions to surgical cases. A three-dimensional orbital model was rendered in 4 representative patients presenting with primary orbital tumors using OsiriX open source imaging software. A 2-Dimensional plane was propagated between the contralateral nare and a line tangential to the long axis of the optic nerve reflecting the trajectory of a trans-septal approach. Any tumor volume falling medial to the optic nerve and/or within the space inferior to this plane of resectability was considered theoretically resectable regardless of how far it extended lateral to the optic nerve as nerve retraction would be unnecessary. Actual tumor volumes were then superimposed over this plan and correlated with surgical outcomes. Among the 4 lesions analyzed, two were fully medial to the optic nerve, one extended lateral to the optic nerve but remained inferior to the plane of resectability, and one extended both lateral to the optic nerve and superior to the plane of resectability. As predicted by the three-dimensional modeling, a complete resection was achieved in all lesions except one that transgressed the plane of resectability. No new diplopia or vision loss was observed in any patient. Three-dimensional reconstruction enhances preoperative planning for endoscopic orbital surgery. Tumors that extend lateral to the optic nerve may still be candidates for a purely endoscopic resection as long as they do not extend above the plane of resectability described herein. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

In vivo thickness and birefringence determination of the human retinal nerve fiber layer using polarization-sensitive optical coherence tomography.

PubMed

Cense, B; Chen, T C; de Boer, J F

2006-01-01

Thinning of the retinal nerve fiber layer and changes in retinal nerve fiber layer birefringence may both precede clinically detectable glaucomatous vision loss. We present in vivo thickness and depth-resolved birefringence measurements of the human retinal nerve fiber layer (RNFL) by use of polarization-sensitive optical coherence tomography (PS-OCT). Using a fiber-based PS-OCT setup real-time images of the human retina in vivo were recorded, co-registered with retinal video images of the location of PS-OCT scans. PS-OCT scans around the optic nerve head (ONH) of two healthy young volunteers were made using 10 concentric circles of increasing radius. Both the mean retinal nerve fiber layer thickness and mean retinal nerve fiber birefringence for each of 48 sectors on a circle were determined. The retinal nerve fiber layer thickness and birefringence varied as a function of sector around the ONH. Measured double pass phase retardation per unit depth values around the ONH range between 0.10 and 0.35 degrees/microm. The retinal nerve fiber layer becomes thinner with increasing distance from the ONH. In contrast, the birefringence does not vary significantly with increasing distance from the ONH.

Indocyanine Green Videoangiography Transoptic Visualization and Clipping Confirmation of an Optic Splitting Ophthalmic Artery Aneurysm.

PubMed

Rustemi, Oriela; Cester, Giacomo; Causin, Francesco; Scienza, Renato; Della Puppa, Alessandro

2016-06-01

Ophthalmic artery aneurysms with medial and superior projection in exceptionally rare cases can split the optic nerve. Treatment of these aneurysms is challenging, because the aneurysm dome is hidden from the optic nerve, rendering its visualization and clipping confirmation difficult. In addition, optic nerve function should be preserved during surgical maneuvers. Preoperative detection of this growing feature is usually missing. We illustrate the first case of indocyanine green videoangiography (ICG-VA) application in an optic penetrating ophthalmic artery aneurysm treatment. A 57-year-old woman presented with temporal hemianopsia, slight right visual acuity deficit, and new onset of headache. The cerebral angiography detected a right ophthalmic artery aneurysm medially and superiorly projecting. The A1 tract of the ipsilateral anterior cerebral artery was elevated and curved, being suspicious for an under optic aneurysm growth. Surgery was performed. Initially the aneurysm was not visible. ICG-VA permitted the transoptic aneurysm visualization. After optic canal opening, the aneurysm was clipped and transoptic ICG-VA confirmed the aneurysm occlusion. ICG-VA showed also the slight improvement of the optic nerve pial vascularization. Postoperatively, the visual acuity was 10/10 and the hemianopsia did not worsen. The elevation and curve of the A1 tract in medially and superiorly projecting ophthalmic aneurysms may be an indirect sign of under optic growth, or optic splitting aneurysms. ICG-VA transoptic aneurysm detection and occlusion confirmation reduces the surgical maneuvers on the optic nerve, contributing to function preservation. Copyright © 2016 Elsevier Inc. All rights reserved.

Utility of coronal contrast-enhanced fat-suppressed FLAIR in the evaluation of optic neuropathy and atrophy.

PubMed

Boegel, Kevin H; Tyan, Andrew E; Iyer, Veena R; Rykken, Jeffrey B; McKinney, Alexander M

2017-01-01

Evaluating chronic sequelae of optic neuritis, such as optic neuropathy with or without optic nerve atrophy, can be challenging on whole brain MRI. This study evaluated the utility of dedicated coronal contrast-enhanced fat-suppressed FLAIR (CE-FS-FLAIR) MR imaging to detect optic neuropathy and optic nerve atrophy. Over 4.5 years, a 3 mm coronal CE-FS-FLAIR sequence at 1.5T was added to the routine brain MRIs of 124 consecutive patients, 102 of whom had suspected or known demyelinating disease. Retrospective record reviews confirmed that 28 of these 102 had documented onset of optic neuritis >4 weeks prior to the brain MRI. These 28 were compared to the other 22 ("controls") of the 124 patients who lacked a history of demyelinating disease or visual symptoms. Using coronal CE-FS-FLAIR, two neuroradiologists separately graded each optic nerve (n = 50 patients, 100 total nerves) as either negative, equivocal, or positive for optic neuropathy or atrophy. The scoring was later repeated. The mean time from acute optic neuritis onset to MRI was 4.1 ± 4.6 years (range 34 days-17.4 years). Per individual nerve grading, the range of sensitivity, specificity, and accuracy of coronal CE-FS-FLAIR in detecting optic neuropathy was 71.4-77.1%, 93.8-95.4%, and 85.5-89.0%, respectively, with strong interobserver (k = 0.667 - 0.678, p < 0.0001), and intraobserver (k = 0.706 - 0.763, p < 0.0001) agreement. For optic atrophy, interobserver agreement was moderate (k = 0.437 - 0.484, p < 0.0001), while intraobserver agreement was moderate-strong (k = 0.491 - 0.596, p < 0.0001). Coronal CE-FS-FLAIR is quite specific in detecting optic neuropathy years after the onset of acute optic neuritis, but is less useful in detecting optic nerve atrophy.

The optic nerve: A “mito-window” on mitochondrial neurodegeneration

PubMed Central

Maresca, Alessandra; la Morgia, Chiara; Caporali, Leonardo; Valentino, Maria Lucia; Carelli, Valerio

2013-01-01

Retinal ganglion cells (RGCs) project their long axons, composing the optic nerve, to the brain, transmitting the visual information gathered by the retina, ultimately leading to formed vision in the visual cortex. The RGC cellular system, representing the anterior part of the visual pathway, is vulnerable to mitochondrial dysfunction and optic atrophy is a very frequent feature of mitochondrial and neurodegenerative diseases. The start of the molecular era of mitochondrial medicine, the year 1988, was marked by the identification of a maternally inherited form of optic atrophy, Leber's hereditary optic neuropathy, as the first disease due to mitochondrial DNA point mutations. The field of mitochondrial medicine has expanded enormously over the last two decades and many neurodegenerative diseases are now known to have a primary mitochondrial etiology or mitochondrial dysfunction plays a relevant role in their pathogenic mechanism. Recent technical advancements in neuro-ophthalmology, such as optical coherence tomography, prompted a still ongoing systematic re-investigation of retinal and optic nerve involvement in neurodegenerative disorders. In addition to inherited optic neuropathies, such as Leber's hereditary optic neuropathy and dominant optic atrophy, and in addition to the syndromic mitochondrial encephalomyopathies or mitochondrial neurodegenerative disorders such as some spinocerebellar ataxias or familial spastic paraparesis and other disorders, we draw attention to the involvement of the optic nerve in classic age-related neurodegenerative disorders such as Parkinson and Alzheimer disease. We here provide an overview of optic nerve pathology in these different clinical settings, and we review the possible mechanisms involved in the pathogenesis of optic atrophy. This may be a model of general value for the field of neurodegeneration. This article is part of a Special Issue entitled ‘Mitochondrial function and dysfunction in neurodegeneration’. PMID:22960139

Acute optic nerve sheath fenestration in humans using the free electron laser (FEL): a case report

NASA Astrophysics Data System (ADS)

Joos, Karen M.; Mawn, Louise A.; Shen, Jin-Hui; Jansen, E. Duco; Casagrande, Vivien A.

2002-06-01

Our previous studies using rabbits and monkeys showed that the Amide II wavelength (6.45 micrometers ) produced by the FEL could efficiently produce an optic nerve sheath fenestration with minimal damage. In order to determine if the technology safely could be applied to human surgery, we used 2 blind human eyes during enucleation to compare the results of producing fenestrations with the FEL or a scissors. FDA and Vanderbilt IRB approvals, and individual patient consents were obtained. The FEL energy was transmitted to a human operating room. After disinsertion of the medial rectus muscle, an optic nerve sheath fenestration (2 mm diameter) was made with either the FEL (6.45 micrometers , 325 micrometers spot size, 30 Hz, 3 mJ) through a hollow waveguide surgical probe or with a scissors. The enucleation was then completed. The optic nerve was dissected from the globe and fixed. Specimens were examined histologically. Dural incisions were effective with both methods. FEL energy at 6.45 micrometers can be transmitted to an operating room and delivered to human ocular tissue through a hollow waveguide surgical probe. This FEL wavelength can produce an optic nerve sheath fenestration without acute direct damage to the nerve in this case report.

Extralaryngeal division of the recurrent laryngeal nerve: A common and asymmetric anatomical variant

PubMed Central

Uludağ, Mehmet; Yetkin, Gürkan; Oran, Ebru Şen; Aygün, Nurcihan; Celayir, Fevzi; İşgör, Adnan

2017-01-01

Objective Recognition of extralaryngeal branching of the recurrent laryngeal nerve is crucial because prevention of vocal cord paralysis requires preservation of all branches of the recurrent laryngeal nerve. We assessed the prevalence of extralaryngeal branching of the recurrent laryngeal nerve and the median branching distance from the point of bifurcation to the entry point of the nerve into the larynx. Material and Methods Prospective operative data on recurrent laryngeal nerve branching were collected from 94 patients who underwent thyroid or parathyroid surgery between September 2011 and May 2012. Results A total of 161 recurrent laryngeal nerves were examined (82 right, 79 left). Overall, 77 (47.8%) of 161 recurrent laryngeal nerves were bifurcated before entering the larynx. There were 36 (43.9%) branching nerves on the right and 41 (51.9%) branching nerves on the left, and there was no significant difference between the sides in terms of branching (p=0.471). Among 67 patients who underwent bilateral exploration, 28.4% were found to have bilateral branching, 40.3% had unilateral branching, and the remaining 31.3% had no branching. The median branching distance was 15 mm (5–60mm). Conclusion Extralaryngeal division of recurrent laryngeal nerve is a common and asymmetric anatomical variant. These variations can be easily recognized if the recurrent laryngeal nerve is identified at the level of the inferior thyroid artery and then dissected totally to the entry point of the larynx. Inadvertent division of a branch may lead to vocal cord palsy postoperatively, even when the surgeon believes the integrity of the nerve has been preserved. PMID:28944327

Extralaryngeal division of the recurrent laryngeal nerve: A common and asymmetric anatomical variant.

PubMed

Uludağ, Mehmet; Yetkin, Gürkan; Oran, Ebru Şen; Aygün, Nurcihan; Celayir, Fevzi; İşgör, Adnan

2017-01-01

Recognition of extralaryngeal branching of the recurrent laryngeal nerve is crucial because prevention of vocal cord paralysis requires preservation of all branches of the recurrent laryngeal nerve. We assessed the prevalence of extralaryngeal branching of the recurrent laryngeal nerve and the median branching distance from the point of bifurcation to the entry point of the nerve into the larynx. Prospective operative data on recurrent laryngeal nerve branching were collected from 94 patients who underwent thyroid or parathyroid surgery between September 2011 and May 2012. A total of 161 recurrent laryngeal nerves were examined (82 right, 79 left). Overall, 77 (47.8%) of 161 recurrent laryngeal nerves were bifurcated before entering the larynx. There were 36 (43.9%) branching nerves on the right and 41 (51.9%) branching nerves on the left, and there was no significant difference between the sides in terms of branching (p=0.471). Among 67 patients who underwent bilateral exploration, 28.4% were found to have bilateral branching, 40.3% had unilateral branching, and the remaining 31.3% had no branching. The median branching distance was 15 mm (5-60mm). Extralaryngeal division of recurrent laryngeal nerve is a common and asymmetric anatomical variant. These variations can be easily recognized if the recurrent laryngeal nerve is identified at the level of the inferior thyroid artery and then dissected totally to the entry point of the larynx. Inadvertent division of a branch may lead to vocal cord palsy postoperatively, even when the surgeon believes the integrity of the nerve has been preserved.

Bell's Palsy in Children: Role of the School Nurse in Early Recognition and Referral

ERIC Educational Resources Information Center

Gordon, Shirley C.

2008-01-01

Bell's palsy is the most common condition affecting facial nerves. It is an acute, rapidly progressing, idiopathic, unilateral facial paralysis that is generally self-limiting and non-life threatening that occurs in all age groups (Okuwobi, Omole, & Griffith, 2003). The school nurse may be the first person to assess facial palsy and muscle…

[Laryngological experiences in treatment of Bell's palsy].

PubMed

Obrebowski, A; Pruszewicz, A

2001-01-01

Between 1990-2000 15 cases of unilateral Bell paresis of the VIIth nerve were treated using local injection of hydrocortisone in the region of the foramen stylomastoideum. Paralelly were administered iontophoresis, galvanisation of the facial mimic muscles together with vasodilating drugs. Early introduced treatment gave complete return of facialis function. The usefulness of treatment monitoring with topodiagnostic tests is stressed.

Optical stimulation of the facial nerve: a surgical tool?

NASA Astrophysics Data System (ADS)

Richter, Claus-Peter; Teudt, Ingo Ulrik; Nevel, Adam E.; Izzo, Agnella D.; Walsh, Joseph T., Jr.

2008-02-01

One sequela of skull base surgery is the iatrogenic damage to cranial nerves. Devices that stimulate nerves with electric current can assist in the nerve identification. Contemporary devices have two main limitations: (1) the physical contact of the stimulating electrode and (2) the spread of the current through the tissue. In contrast to electrical stimulation, pulsed infrared optical radiation can be used to safely and selectively stimulate neural tissue. Stimulation and screening of the nerve is possible without making physical contact. The gerbil facial nerve was irradiated with 250-μs-long pulses of 2.12 μm radiation delivered via a 600-μm-diameter optical fiber at a repetition rate of 2 Hz. Muscle action potentials were recorded with intradermal electrodes. Nerve samples were examined for possible tissue damage. Eight facial nerves were stimulated with radiant exposures between 0.71-1.77 J/cm2, resulting in compound muscle action potentials (CmAPs) that were simultaneously measured at the m. orbicularis oculi, m. levator nasolabialis, and m. orbicularis oris. Resulting CmAP amplitudes were 0.3-0.4 mV, 0.15-1.4 mV and 0.3-2.3 mV, respectively, depending on the radial location of the optical fiber and the radiant exposure. Individual nerve branches were also stimulated, resulting in CmAP amplitudes between 0.2 and 1.6 mV. Histology revealed tissue damage at radiant exposures of 2.2 J/cm2, but no apparent damage at radiant exposures of 2.0 J/cm2.

Analyzing Sub-Classifications of Glaucoma via SOM Based Clustering of Optic Nerve Images.

PubMed

Yan, Sanjun; Abidi, Syed Sibte Raza; Artes, Paul Habib

2005-01-01

We present a data mining framework to cluster optic nerve images obtained by Confocal Scanning Laser Tomography (CSLT) in normal subjects and patients with glaucoma. We use self-organizing maps and expectation maximization methods to partition the data into clusters that provide insights into potential sub-classification of glaucoma based on morphological features. We conclude that our approach provides a first step towards a better understanding of morphological features in optic nerve images obtained from glaucoma patients and healthy controls.

Novel SOX2 mutations and genotype-phenotype correlation in anophthalmia and microphthalmia.

PubMed

Schneider, Adele; Bardakjian, Tanya; Reis, Linda M; Tyler, Rebecca C; Semina, Elena V

2009-12-01

SOX2 represents a High Mobility Group domain containing transcription factor that is essential for normal development in vertebrates. Mutations in SOX2 are known to result in a spectrum of severe ocular phenotypes in humans, also typically associated with other systemic defects. Ocular phenotypes include anophthalmia/microphthalmia (A/M), optic nerve hypoplasia, ocular coloboma and other eye anomalies. We screened 51 unrelated individuals with A/M and identified SOX2 mutations in the coding region of the gene in 10 individuals. Seven of the identified mutations are novel alterations, while the remaining three individuals carry the previously reported recurrent 20-nucleotide deletion in SOX2, c.70del20. Among the SOX2-positive cases, seven patients had bilateral A/M and mutations resulting in premature termination of the normal protein sequence (7/38; 18% of all bilateral cases), one patient had bilateral A/M associated with a single amino acid insertion (1/38; 3% of bilateral cases), and the final two patients demonstrated unilateral A/M associated with missense mutations (2/13; 15% of all unilateral cases). These findings and review of previously reported cases suggest a potential genotype/phenotype correlation for SOX2 mutations with missense changes generally leading to less severe ocular defects. In addition, we report a new familial case of affected siblings with maternal mosaicism for the identified SOX2 mutation, which further underscores the importance of parental testing to provide accurate genetic counseling to families.

Novel SOX2 Mutations and Genotype-Phenotype Correlation in Anophthalmia and Microphthalmia

PubMed Central

Schneider, Adele; Bardakjian, Tanya; Reis, Linda M.; Tyler, Rebecca C.; Semina, Elena V.

2009-01-01

SOX2 represents a High Mobility Group domain containing transcription factor that is essential for normal development in vertebrates. Mutations in SOX2 are known to result in a spectrum of severe ocular phenotypes in humans, also typically associated with other systemic defects. Ocular phenotypes include anophthalmia/microphthalmia (A/M), optic nerve hypoplasia, ocular coloboma and other eye anomalies. We screened 51 unrelated individuals with A/M and indentified SOX2 mutations in the coding region of the gene in 10 individuals. Seven of the identified mutations are novel alterations, while the remaining three individuals carry the previously reported recurrent 20-nucleotide deletion in SOX2, c.70del20. Among the SOX2-positive cases, seven patients had bilateral A/M and mutations resulting in premature termination of the normal protein sequence (7/38; 18% of all bilateral cases), one patient had bilateral A/M associated with a single amino acid insertion (1/38; 3% of bilateral cases), and the final two patients demonstrated unilateral A/M associated with missense mutations (2/13; 15% of all unilateral cases). These findings and review of previously reported cases suggest a potential genotype/phenotype correlation for SOX2 mutations with missense changes generally leading to less severe ocular defects. In addition, we report a new familial case of affected siblings with maternal mosaicism for the identified SOX2 mutation, which further underscores the importance of parental testing to provide accurate genetic counseling to families. PMID:19921648

Regeneration-associated genes on optic nerve regeneration in fish retina.

PubMed

Ogai, Kazuhiro; Nishitani, Maki; Kuwana, Ayaka; Mawatari, Kazuhiro; Koriyama, Yoshiki; Sugitani, Kayo; Nakashima, Hiroshi; Kato, Satoru

2014-01-01

It has been well documented that fish central nervous system, including retina and optic nerve, can regenerate and recover its function after nerve injury. Within a few decades, a number of regeneration-associated genes (RAGs) have been identified in fish retina following optic nerve injury (ONI). RAGs can be classified into two groups: cell survival- and axonal outgrowth-related genes. In fish retina after ONI, cell survival-related genes were upregulated in 1-6 days after ONI, which corresponds to the preparation stage for cell survival and axonal sprouting. Subsequently, axonal outgrowth-related genes were upregulated in 1-6 weeks after ONI, which corresponds to the axonal regrowth stage. Recently, we've found a novel type of RAGs, dedifferentiation-related genes, that are upregulated in overlapping time between cell survival and axonal regrowth (3-10 days after ONI). In this chapter we summarize these three types of RAGs that promote optic nerve regeneration in the fish retina after ONI.

Modeling the Effects of Spaceflight on the Posterior Eye in VIIP

NASA Technical Reports Server (NTRS)

Ethier, C. R.; Feola, A. J.; Raykin, J.; Mulugeta, L.; Gleason, R.; Myers, J. G.; Nelson, E. S.; Samuels, B.

2015-01-01

Purpose: Visual Impairment and Intracranial Pressure (VIIP) syndrome is a new and significant health concern for long-duration space missions. Its etiology is unknown, but is thought to involve elevated intracranial pressure (ICP)that induces connective tissue changes and remodeling in the posterior eye (Alexander et al. 2012). Here we study the acute biomechanical response of the lamina cribrosa (LC) and optic nerve to elevations in ICP utilizing finite element (FE) modeling. Methods: Using the geometry of the posterior eye from previous axisymmetric FE models (Sigal et al. 2004), we added an elongated optic nerve and optic nerve sheath, including the pia and dura. Tissues were modeled as linear elastic solids. Intraocular pressure and central retinal vessel pressures were set at 15 mmHg and 55 mmHg, respectively. ICP varied from 0 mmHg (suitable for standing on earth) to 30 mmHg (representing severe intracranial hypertension, thought to occur in space flight). We focused on strains and deformations in the LC and optic nerve (within 1 mm of the LC) since we hypothesize that they may contribute to vision loss in VIIP. Results: Elevating ICP from 0 to 30 mmHg significantly altered the strain distributions in both the LC and optic nerve (Figure), notably leading to more extreme strain values in both tension and compression. Specifically, the extreme (95th percentile) tensile strains in the LC and optic nerve increased by 2.7- and 3.8-fold, respectively. Similarly, elevation of ICP led to a 2.5- and 3.3-fold increase in extreme (5th percentile) compressive strains in the LC and optic nerve, respectively. Conclusions: The elevated ICP thought to occur during spaceflight leads to large acute changes in the biomechanical environment of the LC and optic nerve, and we hypothesize that such changes can activate mechanosensitive cells and invoke tissue remodeling. These simulations provide a foundation for more comprehensive studies of microgravity effects on human vision, e.g. to guide biological studies in which cells and tissues are mechanically loaded in a ranger elevant for microgravity conditions.

Intermedius nerve involvement and testing in acoustic neuromas.

PubMed

Thomsen, J; Zilstorff, K

1975-01-01

The clinical findings in 125 patients with surgically confirmed acoustic neuromas are presented, with special regard to the involvement of the intermedius nerve in the diagnosis. In assessing the function of the intermedius nerve the examination of the nasolacrimal reflex and the sensation of taste on the anterior two-thirds of the tongue are used. The methods of investigation are described in detail. The material consisted of 20 medium-sized and 105 large tumours; no intracanalicular tumor was found. Hearing loss was the initial symptom in 85% of the patients, 10% had tinitus and 4% vertigo as the first symptom. Apart from the VIII cranial nerve symptoms, a defective nasolacrimal reflex was the most significant evidence of cerebellopontine angle pathology. The test was positive in 65% of the medium-sized tumours, in the entire material, 85%. The figures are higher than the incidence of trigeminal nerve symptoms. This in contrast to the reports of most authors. The tests described are simple and quick to perform, and it is emphasized that they should be applied to all patients with unilateral hearing loss of unknown origin.

Attenuation of TRPV1 by AMG-517 after nerve injury promotes peripheral axonal regeneration in rats.

PubMed

Bai, Juan; Liu, Fu; Wu, Li-Fei; Wang, Ya-Fang; Li, Xia-Qing

2018-01-01

Aims The main objective was to investigate the effects of the transient receptor potential cation channel subfamily V member 1 (TRPV1) on nerve regeneration following sciatic transection injury by functional blockage of TRPV1 using AMG-517, a specific blocker of TRPV1. Methods AMG-517 was injected into the area surrounding ipsilateral lumbar dorsal root ganglia 30 min after unilateral sciatic nerve transection. The number of sciatic axons and the expression of growth-associated protein-43 (GAP-43) and glial fibrillary acidic protein was examined using semithin sections, Western blot, and immunofluorescence analyses. Results Blockage of TRPV1 with AMG-517 markedly promoted axonal regeneration, especially at two weeks after sciatic injury; the number of axons was similar to the uninjured control group. After sciatic nerve transection, expression of glial fibrillary acidic protein was decreased and GAP-43 was increased at the proximal stump. However, the expression of both glial fibrillary acidic protein and GAP-43 increased significantly in AMG-517-treated groups. Conclusions TRPV1 may be an important therapeutic target to promote peripheral nerve regeneration after injury.

New pain-relieving strategies for topical photodynamic therapy

NASA Astrophysics Data System (ADS)

Halldin, Christina B.; Paoli, John; Sandberg, Carin; Ericson, Marica B.; Gonzalez, Helena; Wennberg, Ann-Marie

2009-06-01

PDT is an effective method when treating multiple actinic keratoses (field cancerization). The major side effect is pain. Our objectives were to investigate the pain-relieving effect of transcutaneous electrical nerve stimulation (TENS) and peripheral nerve blocks during PDT of field cancerization (FC) of the face and scalp. Patients with field cancerization were included in three studies. In the first study, we examined TENS with an application site on the adjacent dermatome from the PDT area in order to allow the use of water spray during PDT for FC of the scalp and face. In the second study, patients with FC in the facial area received unilateral supraorbital, infraorbital and/or mental nerve blocks. The non-anaesthetised side of the treatment area served as control. In the third study, with similar methodology as in the second study, occipital and supraorbital nerve blocks were combined for FC of the forehead and scalp. The results of the studies strongly support the use of nerve blocks as pain relief during PDT. The use of TENS provided a limited pain reduction, but TENS might be an alternative if the patient disapproves of the use of nerve blocks or is afraid of injections.

Nitrergic nerves derived from the pterygopalatine ganglion innervate arteries irrigating the cerebrum but not the cerebellum and brain stem in monkeys.

PubMed

Ayajiki, Kazuhide; Kobuchi, Shuhei; Tawa, Masashi; Okamura, Tomio

2012-01-01

The functional roles of the nitrergic nerves innervating the monkey cerebral artery were evaluated in a tension-response study examining isolated arteries in vitro and cerebral angiography in vivo. Nicotine produced relaxation of arteries by stimulation of nerve terminals innervating isolated monkey arteries irrigating the cerebrum, cerebellum and brain stem. Relaxation of arteries induced by nicotine was abolished by treatment with N(G)-nitro-L-arginine, a nitric oxide synthase inhibitor, and was restored by addition of L-arginine. Cerebral angiography showed that electrical stimulation of the unilateral greater petrosal nerve, which connects to the pterygopalatine ganglion via the parasympathetic ganglion synapse, produced vasodilatation of the anterior, middle and posterior cerebral arteries in the stimulated side. However, stimulation failed to produce vasodilatation of the superior and anterior-inferior cerebellar arteries and the basilar artery in anesthetized monkeys. Therefore, nitrergic nerves derived from the pterygopalatine ganglion appear to regulate cerebral vasomotor function. In contrast, circulation in the cerebellum and brain stem might be regulated by nitrergic nerves originating not from the pterygopalatine ganglion, but rather from an unknown ganglion (or ganglia).

Neuronal network-based mathematical modeling of perceived verticality in acute unilateral vestibular lesions: from nerve to thalamus and cortex.

PubMed

Glasauer, S; Dieterich, M; Brandt, T

2018-05-29

Acute unilateral lesions of vestibular graviceptive pathways from the otolith organs and semicircular canals via vestibular nuclei and the thalamus to the parieto-insular vestibular cortex regularly cause deviations of perceived verticality in the frontal roll plane. These tilts are ipsilateral in peripheral and in ponto-medullary lesions and contralateral in ponto-mesencephalic lesions. Unilateral lesions of the vestibular thalamus or cortex cause smaller tilts of the perceived vertical, which may be either ipsilateral or contralateral. Using a neural network model, we previously explained why unilateral vestibular midbrain lesions rarely manifest with rotational vertigo. We here extend this approach, focussing on the direction-specific deviations of perceived verticality in the roll plane caused by acute unilateral vestibular lesions from the labyrinth to the cortex. Traditionally, the effect of unilateral peripheral lesions on perceived verticality has been attributed to a lesion-based bias of the otolith system. We here suggest, on the basis of a comparison of model simulations with patient data, that perceived visual tilt after peripheral lesions is caused by the effect of a torsional semicircular canal bias on the central gravity estimator. We further argue that the change of gravity coding from a peripheral/brainstem vectorial representation in otolith coordinates to a distributed population coding at thalamic and cortical levels can explain why unilateral thalamic and cortical lesions have a variable effect on perceived verticality. Finally, we propose how the population-coding network for gravity direction might implement the elements required for the well-known perceptual underestimation of the subjective visual vertical in tilted body positions.

Optic nerve sheath fenestration using a Raman-shifted alexandrite laser

PubMed Central

Kozub, John; Shen, Jin-H.; Joos, Karen M.; Prasad, Ratna; Hutson, M. Shane

2016-01-01

Background and Objective Optic nerve sheath fenestration is an established procedure for relief of potentially damaging overpressure on the optic nerve resulting from idiopathic intracranial hypertension. Prior work showed that a mid-IR free-electron laser could be delivered endoscopically and used to produce an effective fenestration. This study evaluates the efficacy of fenestration using a table-top mid-IR source based on a Raman-shifted alexandrite (RSA) laser. Study Design/Materials and Methods Porcine optic nerves were ablated using light from an RSA laser at wavelengths of 6.09, 6.27 and 6.43 μm and pulse energies up to 3 mJ using both free-space and endoscopic beam delivery through 250-μm I.D. hollow-glass waveguides. Waveguide transmission was characterized, ablation thresholds and etch rates were measured, and the efficacy of endoscopic fenestration was evaluated for ex vivo exposures using both optical coherence tomography and histological analysis. Results Using endoscopic delivery, the RSA laser can effectively fenestrate porcine optic nerves. Performance was optimized at a wavelength of 6.09 μm and delivered pulse energies of 0.5-0.8 mJ (requiring 1.5-2.5 mJ to be incident on the waveguide). Under these conditions, the ablation threshold fluence was 0.8 ± 0.2 J/cm2, the ablation rate was 1-4 μm/pulse, and the margins of ablation craters showed little evidence of thermal or mechanical damage. Nonetheless, nominally identical exposures yielded highly variable ablation rates. This led to fenestrations that ranged from too deep to too shallow – either damaging the underlying optic nerve or requiring additional exposure to cut fully through the sheath. Of 48 excised nerves subjected to fenestration at 6.09 μm, 16 ex vivo fenestrations were judged as good, 23 as too deep, and 9 as too shallow. Conclusions Mid-IR pulses from the RSA laser, propagated through a flexible hollow waveguide, are capable of cutting through porcine optic nerve sheaths in surgically relevant times with reasonable accuracy and low collateral damage. This can be accomplished at wavelengths of 6.09 or 6.27 μm, with 6.09 μm slightly preferred. The depth of ex vivo fenestrations was difficult to control, but excised nerves lack a sufficient layer of cerebrospinal fluid that would provide an additional margin of safety in actual patients. PMID:27020001

FIBER-OPTIC BIOSENSOR FOR DIRECT DETERMINATION OF ORGANOPHOSPHATE NERVE AGENTS. (R823663)

EPA Science Inventory

A fiber-optic enzyme biosensor for the direct measurement of organophosphate nerve
agents was developed. The basic element of this biosensor is organophosphorus hydrolase
immobilized on a nylon membrane and attached to the common end of a bifurcated optical fiber
bundle....

Neuroprotective Strategies for the Treatment of Blast-Induced Optic Neuropathy

DTIC Science & Technology

2016-09-01

will examine alterations in the amacrine cells and ganglion cells as well as therapeutic outcome measures including electroretinogram, visual evoked...nerve degeneration.1-3 This suggests that degeneration of the retinal ganglion cell (RGC) axons in the optic nerve is a secondary event. Secondary...for neurodegenerations from trauma extending beyond optic neuropathy. 2. Keywords: retinal ganglion cell (RGC), traumatic optic neuropathy

A System for Delivering Mechanical Stimulation and Robot-Assisted Therapy to the Rat Whisker Pad during Facial Nerve Regeneration

PubMed Central

Heaton, James T.; Knox, Christopher; Malo, Juan; Kobler, James B.; Hadlock, Tessa A.

2013-01-01

Functional recovery is typically poor after facial nerve transection and surgical repair. In rats, whisking amplitude remains greatly diminished after facial nerve regeneration, but can recover more completely if the whiskers are periodically mechanically stimulated during recovery. Here we present a robotic “whisk assist” system for mechanically driving whisker movement after facial nerve injury. Movement patterns were either pre-programmed to reflect natural amplitudes and frequencies, or movements of the contralateral (healthy) side of the face were detected and used to control real-time mirror-like motion on the denervated side. In a pilot study, twenty rats were divided into nine groups and administered one of eight different whisk assist driving patterns (or control) for 5–20 minutes, five days per week, across eight weeks of recovery after unilateral facial nerve cut and suture repair. All rats tolerated the mechanical stimulation well. Seven of the eight treatment groups recovered average whisking amplitudes that exceeded controls, although small group sizes precluded statistical confirmation of group differences. The potential to substantially improve facial nerve recovery through mechanical stimulation has important clinical implications, and we have developed a system to control the pattern and dose of stimulation in the rat facial nerve model. PMID:23475376

Ultrasound-Guided Intermediate Site Greater Occipital Nerve Infiltration: A Technical Feasibility Study.

PubMed

Zipfel, Jonathan; Kastler, Adrian; Tatu, Laurent; Behr, Julien; Kechidi, Rachid; Kastler, Bruno

2016-01-01

Two studies recently reported that computed tomography (CT) guided infiltration of the greater occipital nerve at its intermediate site allows a high efficacy rate with long-lasting pain relief following procedure in occipital neuralgia and in various craniofacial pain syndromes. The purpose of our study was to evaluate the technical feasibility and safety of ultrasound-guided intermediate site greater occipital nerve infiltration. Retrospective study. This study was conducted at the imaging department of a 1,409 bed university hospital. Local institutional review board approval was obtained and written consent was waived. In this retrospective study, 12 patients suffering from refractory occipital neuralgia or craniofacial pain syndromes were included between April and October 2014. They underwent a total of 21 ultrasound-guided infiltrations. Infiltration of the greater occipital nerve was performed at the intermediate site of the greater occipital nerve, at its first bend between obliqus capitis inferior and semispinalis capitis muscles with local anestetics and cortivazol. Technical success was defined as satisfactory diffusion of added iodinated contrast media in the fatty space between these muscles depicted on control CT scan. We also reported first data of immediate block test efficacy and initial clinical efficacy at 7 days, one month, and 3 months, defined by a decrease of at least 50% of visual analog scale (VAS) scores. Technical success rate was 95.24%. Patients suffered from right unilateral occipital neuralgia in 3 cases, left unilateral occipital neuralgia in 2 cases, bilateral occipital neuralgia in 2 cases, migraine in one case, cervicogenic headache in one case, tension-type headache in 2 cases, and cluster headache in one case. Block test efficacy was found in 93.3% (14/15) cases. Clinical efficacy was found in 80% of cases at 7 days, in 66.7% of cases at one month and in 60% of cases at 3 months. No major complications were noted. Some of the limitations of our study include that it represents a single institution. The low number of infiltrations included in this study, for this guidance procedure, is another bias. This ultrasound-guided infiltration technique appears to be feasible, safe, non-ionizing, and fast when targeting the greater occipital nerve in its intermediate portion. This imaging guidance modality should be used in routine clinical practice. Greater occipital nerve, infiltration, ultrasound guidance, corticosteroids, occipital neuralgia, craniofacial pain syndrome.

Analysis of the Istanbul Forensic Medicine Institute expert decisions on recurrent laryngeal nerve injuries due to thyroidectomy between 2008–2012

PubMed Central

Karakaya, M. Arif; Koç, Okay; Ekiz, Feza; Ağaçhan, A. Feran; Göret, Nuri Emrah

2016-01-01

Objective: The aim of this study was to evaluate the approach of Forensic Medicine Institution for recurrent laryngeal nerve injuries. In addition, parameters that were taken into consideration by Forensic Medicine Institution in the differentiation of complication and malpractice were evaluated. Material and Methods: The files of 38 patients, with recurrent laryngeal nerve injury following thyroidectomy, that were referred to Istanbul Forensic Medicine Institute with request of expert opinion between 2008–2012 were retrospectively investigated. Data regarding expert decisions, age, gender, diagnosis, hospital type, preoperative vocal cord examination, intraoperative nerve monitoring (IONM), identification of nerve injury during operation, repair of nerve during operation, and type of injury were assessed. Results: Surgeons were found to be faulty in all files with bilateral nerve injury, however, one-sided injury files were considered as a medical complication. Twenty-one (55.2%) patients were female, and 17 (44.8%) were male, with a mean age of 35,8 in women, and 34,1 in men. None of these patients had undergone preoperative vocal cord assessment. The recurrent laryngeal nerve was intraoperatively identified in 21 (55.2%) patients, while it was not seen in 17 (44.8%) patients. IONM was not applied in any patients. There was no attempt for nerve repair during any operation. Nineteen patients had unilateral, and 19 patients had bilateral nerve damage. Conclusion: Bilateral recurrent laryngeal nerve injuries are considered as malpractice, when imaging or pathology reports fail to state a cause for difficulty in nerve identification. PMID:26985157

Development of a nerve conduction technique for the recurrent laryngeal nerve.

PubMed

J Kim, Sang; G Lee, Dae; Kwon, Jeong-Yi

2014-12-01

To develop a reliable and safe laryngeal nerve conduction technique and to obtain consistent parameters as normal reference values. A prospective single-arm study. A nerve conduction test was performed on the contralateral normal side in 42 patients with unilateral vocal fold palsy. The recording was performed in the intact thyroarytenoid muscle using a monopolar needle. The electrical stimulation using a 37-mm monopolar needle was applied 3 cm below the lower margin of the cricoid cartilage, just lateral to the trachea and medial to the carotid artery, and its intensity was gradually increased until the amplitude of the electrical response reached the maximum level. The latency of the evoked muscle response was acquired at the first evoked waveform deflection from the baseline. The average latency of the recurrent laryngeal nerves was 1.98 ± 0.26 ms. The latencies showed normal distribution according to the quantile-quantile plot and Kolmogorov-Smirnov test (P = .098). There was no significant difference in latencies between the right and left recurrent laryngeal nerves. Anthropometric factors including height and weight did not show any correlation with the latencies. We developed a reliable and safe laryngeal nerve conduction technique and obtained normal reference values for the recurrent laryngeal nerve conduction study. This laryngeal nerve conduction study can be an additional tool for detecting recurrent laryngeal nerve injury if it is performed in combination with the conventional laryngeal electromyography. 4. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

Congenital anomalies of the optic nerve

PubMed Central

Amador-Patarroyo, Manuel J.; Pérez-Rueda, Mario A.; Tellez, Carlos H.

2014-01-01

Congenital optic nerve head anomalies are a group of structural malformations of the optic nerve head and surrounding tissues, which may cause congenital visual impairment and blindness. Each entity in this group of optic nerve anomalies has individually become more prevalent as our ability to differentiate between them has improved due to better characterization of cases. Access to better medical technology (e.g., neuroimaging and genetic analysis advances in recent years) has helped to expand our knowledge of these abnormalities. However, visual impairment may not be the only problem in these patients, some of these entities will be related to ophthalmologic, neurologic and systemic features that will help the physician to identify and predict possible outcomes in these patients, which sometimes may be life-threatening. Herein we present helpful hints, associations and management (when plausible) for them. PMID:25859137

Reduced ventral cingulum integrity and increased behavioral problems in children with isolated optic nerve hypoplasia and mild to moderate or no visual impairment.

PubMed

Webb, Emma A; O'Reilly, Michelle A; Clayden, Jonathan D; Seunarine, Kiran K; Dale, Naomi; Salt, Alison; Clark, Chris A; Dattani, Mehul T

2013-01-01

To assess the prevalence of behavioral problems in children with isolated optic nerve hypoplasia, mild to moderate or no visual impairment, and no developmental delay. To identify white matter abnormalities that may provide neural correlates for any behavioral abnormalities identified. Eleven children with isolated optic nerve hypoplasia (mean age 5.9 years) underwent behavioral assessment and brain diffusion tensor imaging, Twenty four controls with isolated short stature (mean age 6.4 years) underwent MRI, 11 of whom also completed behavioral assessments. Fractional anisotropy images were processed using tract-based spatial statistics. Partial correlation between ventral cingulum, corpus callosum and optic radiation fractional anisotropy, and child behavioral checklist scores (controlled for age at scan and sex) was performed. Children with optic nerve hypoplasia had significantly higher scores on the child behavioral checklist (p<0.05) than controls (4 had scores in the clinically significant range). Ventral cingulum, corpus callosum and optic radiation fractional anisotropy were significantly reduced in children with optic nerve hypoplasia. Right ventral cingulum fractional anisotropy correlated with total and externalising child behavioral checklist scores (r = -0.52, p<0.02, r = -0.46, p<0.049 respectively). There were no significant correlations between left ventral cingulum, corpus callosum or optic radiation fractional anisotropy and behavioral scores. Our findings suggest that children with optic nerve hypoplasia and mild to moderate or no visual impairment require behavioral assessment to determine the presence of clinically significant behavioral problems. Reduced structural integrity of the ventral cingulum correlated with behavioral scores, suggesting that these white matter abnormalities may be clinically significant. The presence of reduced fractional anisotropy in the optic radiations of children with mild to moderate or no visual impairment raises questions as to the pathogenesis of these changes which will need to be addressed by future studies.

Unilateral severe chronic periodontitis associated with ipsilateral surgical resection of cranial nerves V, VI, and VII.

PubMed

Zavarella, Matthew M; Leblebicioglu, Binnaz; Claman, Lewis J; Tatakis, Dimitris N

2006-01-01

The central and peripheral nervous systems participate in several local physiological and pathological processes. There is experimental evidence that the inflammatory, local immune, and wound healing responses of a tissue can be modulated by its innervation. The aim of this clinical report is to present a case of unilateral severe periodontitis associated with ipsilateral surgical resection of the fifth, sixth, and seventh cranial nerves and to discuss the possible contribution of the nervous system to periodontal pathogenesis. A 39-year-old female patient with a history of a cerebrovascular accident caused by a right pontine arteriovenous malformation and destruction of the right fifth, sixth, and seventh cranial nerves was diagnosed with severe chronic periodontitis affecting only the right maxillary and mandibular quadrants. The patient's oral hygiene was similar for right and left sides of the mouth. Percentages of tooth surfaces carrying dental plaque were 41% and 36% for right and left sides, respectively. Non-surgical and surgical periodontal therapy was performed, and the patient was placed on a regular periodontal maintenance schedule. Healing following initial periodontal therapy and osseous periodontal surgery occurred without complications. Follow-up clinical findings at 1 year revealed stable periodontal health. This case report suggests that periodontal innervation may contribute to the regulation of local processes involved in periodontitis pathogenesis. It also suggests that periodontal therapy can be performed successfully at sites and in patients affected by paralysis.

Simultaneous Median and Ulnar Compression Neuropathy Secondary to a Giant Palmar Lipoma: A Case Report and Review of the Literature

PubMed Central

Unal, Melih; Demirayak, Engin; Acar, Baver

2018-01-01

Lipomas are benign tumors that rarely settle in the hand. They usually present with mass, pain, and nerve compression symptoms. Although isolated median or ulnar nerve compression neuropathy secondary to a lipoma of the hand has been widely reported, simultaneous median and ulnar nerve compression neuropathy are exceedingly rare and there are only three reported cases in the current literature to date. Herein, a case of a 50-year-old woman with a giant palmar lipoma that caused median and ulnar compression neuropathy is presented. The removal of the tumor resulted in the complete recovery of the patient’s symptoms. A deep-seated palmar lipoma should be kept in mind in patients with unilateral compression neuropathy symptoms with a palmar mass. PMID:29666776

Piriformis Syndrome and Endoscopic Sciatic Neurolysis.

PubMed

Knudsen, Joshua S; Mei-Dan, Omer; Brick, Mathew J

2016-03-01

Piriformis syndrome is the compression or the irritation of the sciatic nerve by the adjacent piriformis muscle in the buttock leading to symptoms that include buttock pain, leg pain, and altered neurology in the sciatic nerve distribution. Epidemiological figures of the prevalence are unknown, but are estimated to be about 12.2% to 27%. There is no consensus on the diagnostic criteria. Advancement in magnetic resonance imaging allows us to observe unilateral hyperintensity and bowing of the sciatic nerve. The pathophysiology of the disease includes single blunt trauma, overuse causing piriformis hypertrophy, and long-term microtrauma causing scarring. Treatments include physiotherapy, steroid injections, and surgery. Minimally invasive techniques are emerging with the hope that with less postoperative scar tissue formation, there will be less recurrence of the disease. In this chapter, senior author describes his technique for endoscopic sciatic neurolysis.

Quantitative relations between the eyeball, the optic nerve, and the optic canal important for intracranial pressure monitoring

PubMed Central

2014-01-01

Objective To find correlations between diameters of the optic nerve sheath (ONSD), the eyeball, and the optic canal that might be important for intracranial pressure monitoring. Methods In a prospective cohort study, the CT data of consecutive 400 adults (18+) with healthy eyes and optic nerves and absence of neurological diseases were collected and analyzed. When the CT scans were obtained, the diameters of the optic nerve sheath, the eyeball, and the optic canal were measured and statistically analyzed. The data obtained from the left and from the right eyeballs and optic nerves were compared. The correlation analysis was performed within these variables, with the gender, and the age. Results In healthy persons, the ONSD varies from 3.65 mm to 5.17 mm in different locations within the intraorbital space with no significant difference between sexes and age groups. There is a strong correlation between the eyeball transverse diameter (ETD) and ONSD that can be presented as ONSD/ETD index. In healthy subjects, the ONSD/ETD index equals 0.19. Conclusion The calculation of an index when ONSD is divided by the ETD of the eyeball presents precise normative database for ONSD intracranial pressure measurement technique. When the ONSD is measured for intracranial pressure monitoring, the most stable results can be obtained if the diameter is measured 10 mm from the globe. These data might serve as a normative database at emergency departments and in general neurological practice. PMID:25130267

Quantitative relations between the eyeball, the optic nerve, and the optic canal important for intracranial pressure monitoring.

PubMed

Vaiman, Michael; Gottlieb, Paul; Bekerman, Inessa

2014-08-17

To find correlations between diameters of the optic nerve sheath (ONSD), the eyeball, and the optic canal that might be important for intracranial pressure monitoring. In a prospective cohort study, the CT data of consecutive 400 adults (18+) with healthy eyes and optic nerves and absence of neurological diseases were collected and analyzed. When the CT scans were obtained, the diameters of the optic nerve sheath, the eyeball, and the optic canal were measured and statistically analyzed. The data obtained from the left and from the right eyeballs and optic nerves were compared. The correlation analysis was performed within these variables, with the gender, and the age. In healthy persons, the ONSD varies from 3.65 mm to 5.17 mm in different locations within the intraorbital space with no significant difference between sexes and age groups. There is a strong correlation between the eyeball transverse diameter (ETD) and ONSD that can be presented as ONSD/ETD index. In healthy subjects, the ONSD/ETD index equals 0.19. The calculation of an index when ONSD is divided by the ETD of the eyeball presents precise normative database for ONSD intracranial pressure measurement technique. When the ONSD is measured for intracranial pressure monitoring, the most stable results can be obtained if the diameter is measured 10 mm from the globe. These data might serve as a normative database at emergency departments and in general neurological practice.

[The neuroprotective effect of erigeron breviscapus (vant) hand-mazz on retinal ganglion cells after optic nerve crush injury].

PubMed

Jiang, Bing; Jiang, You-qin

2003-08-01

To investigate whether a Chinese herbal medicine, erigeron breviscapus (vant) hand-mazz (EBHM), can protect the retinal ganglion cells (RGC) damaged by calibrated optic nerve crush injury. Forty-two Sprague-Dawley rats were randomly divided into two groups. Calibrated optic nerve crush injury model was induced in the right eyes by a special designed optic nerve clip. The left eyes served as a control. All 42 rats were randomly divided into 2 groups. Group A consisted of the rats with calibrated optic nerve crush injury and group B consisted of rats with calibrated optic nerve crush injury treated with EBHM. In group B, EBHM solution was given once after the crush injury. According to the time interval between the optic nerve crush and the sacrifice, both groups A and B were further divided into three subgroups (day 4, day 14 and day 21). Therefore, there were 7 rats in each subgroup. Three days before sacrifice, 3% fast blue was injected into superior colliculi bilaterally. The eyes were enucleated after the rat was sacrificed, and flat mounts of the retina from both eyes were prepared on a slide and observed under a fluorescence microscope. Four photos with 400 x magnification were taken from each of the four quadrants of the retina 1 mm away from the optic disc. The labeled RGC were counted by a computerized image analyzer. The labeled RGC rate was used for statistical analysis (the labeled RGC rate = number of RGC in injured eye/control eye x 100%). In group A, the labeled RGC rate was (77.79 +/- 7.11)%, (63.76 +/- 3.79)% and (54.66 +/- 4.75)% on day 4, day 14 and day 21, respectively. In group B, the labeled RGC rate was (80.13 +/- 12.03)%, (78.17 +/- 9.19)% and (83.59 +/- 12.61)% on day 4, day 14 and day 21, respectively. In group B, which was treated with EBHM after injury, the labeled RGC rate was significantly higher than that of group A on day 14 and day 21. In the experimental optic nerve crush model in rats, EBHM therapy can increase the survival rate of the RGC and can rescue and/or restore the injured RGC.

Boosting CNS axon regeneration by harnessing antagonistic effects of GSK3 activity.

PubMed

Leibinger, Marco; Andreadaki, Anastasia; Golla, Renate; Levin, Evgeny; Hilla, Alexander M; Diekmann, Heike; Fischer, Dietmar

2017-07-03

Implications of GSK3 activity for axon regeneration are often inconsistent, if not controversial. Sustained GSK3 activity in GSK3 S/A knock-in mice reportedly accelerates peripheral nerve regeneration via increased MAP1B phosphorylation and concomitantly reduces microtubule detyrosination. In contrast, the current study shows that lens injury-stimulated optic nerve regeneration was significantly compromised in these knock-in mice. Phosphorylation of MAP1B and CRMP2 was expectedly increased in retinal ganglion cell (RGC) axons upon enhanced GSK3 activity, but, surprisingly, no GSK3-mediated CRMP2 inhibition was detected in sciatic nerves, thus revealing a fundamental difference between central and peripheral axons. Conversely, genetic or shRNA-mediated conditional KO/knockdown of GSK3β reduced inhibitory phosphorylation of CRMP2 in RGCs and improved optic nerve regeneration. Accordingly, GSK3β KO-mediated neurite growth promotion and myelin disinhibition were abrogated by CRMP2 inhibition and largely mimicked in WT neurons upon expression of constitutively active CRMP2 (CRMP2 T/A ). These results underscore the prevalent requirement of active CRMP2 for optic nerve regeneration. Strikingly, expression of CRMP2 T/A in GSK3 S/A RGCs further boosted optic nerve regeneration, with axons reaching the optic chiasm within 3 wk. Thus, active GSK3 can also markedly promote axonal growth in central nerves if CRMP2 concurrently remains active. Similar to peripheral nerves, GSK3-mediated MAP1B phosphorylation/activation and the reduction of microtubule detyrosination contributed to this effect. Overall, these findings reconcile conflicting data on GSK3-mediated axon regeneration. In addition, the concept of complementary modulation of normally antagonistically targeted GSK3 substrates offers a therapeutically applicable approach to potentiate the regenerative outcome in the injured CNS.

Retinal nerve fiber layer changes after LASIK evaluated with optical coherence tomography.

PubMed

Dementyev, Dmitriy D; Kourenkov, Vyacheslav V; Rodin, Alexander S; Fadeykina, Tatyana L; Diaz Martines, Tatyana E

2005-01-01

To determine whether the increase in intraocular pressure (IOP) during LASIK suction can induce a decrease in retinal nerve fiber layer thickness assessed by optical coherence tomography (OCT). Nineteen patients (38 eyes) were enrolled in the study. Intraocular pressure was normal at all pre- and postoperative examinations. Retinal nerve fiber layer thickness was measured using OCT-3 Stratus prior to and 1 week and 3 months after LASIK. Laser in situ keratomileusis was performed using the Bausch & Lomb Hansatome microkeratome and the NIDEK EC-5000 excimer laser. Optical coherence tomography mean retinal nerve fiber layer thickness values before and after LASIK were compared using the Student paired t test. Mean patient age was 27.8 years (range: 18 to 33 years). Mean preoperative spherical equivalent refractive error was -4.9 diopters (D) (range: -2.0 to -8.5 D). Mean time of microkeratome suction was 30 seconds (range: 20 to 50 seconds). Preoperatively, the mean retinal nerve fiber layer thickness obtained by OCT was 104.2+/-9.0 microm; at 1 week postoperatively the mean thickness was 101.9+/-6.9 microm, and 106.7+/-6.1 microm at 3 months postoperatively. Mean retinal nerve fiber layer thicknesses obtained by OCT were not significantly different between preoperative and 1 week and 3 months after LASIK (P > or = .05). Laser in situ keratomileusis performed on young myopic patients does not have a significant effect on retinal nerve fiber layer thickness determined by OCT. Further studies are required to reveal the risk of possible optic nerve or retinal nerve fiber layer damage by elevated IOP during LASIK.

Peripapillary nerve fiber layer thickness measurement reproducibility using optical coherence tomography.

PubMed

Villain, Max A; Greenfield, David S

2003-01-01

To assess reproducibility of quadrantic and clock hour sectors of retinal nerve fiber layer thickness in normal eyes using optical coherence tomography. Normal eyes of healthy volunteers meeting eligibility criteria were imaged by two inexperienced operators. Six 360 degrees circular scans with a diameter of 3.4 mm centered on the optic disc were obtained during each scanning session, and a baseline image was formed using 3 high-quality images defined by the software. Images were obtained on three different days within a 4-week period. Variance and coefficient of variation (CV) were calculated for quadrantic and retinal nerve fiber layer clock hour sectors obtained from the baseline image. Five normal eyes were scanned. Intraoperator reproducibility was high. The mean (+/- SD) CV for total retinal nerve fiber layer thickness was 5.3 +/- 3.82% and 4.33 +/- 3.7% for operators 1 and 2, respectively. Interoperator reproducibility was good with statistically similar variance for all quadrantic and clock hour retinal nerve fiber layer parameters (P = .42 to .99). The nasal retinal nerve fiber layer was the most variable sector for both operators (mean CV: 10.42% and 7.83% for operators 1 and 2, respectively). Differences in mean total, nasal, temporal, and superior retinal nerve fiber layer thickness were not statistically significant between operators for all eyes; however, for inferior retinal nerve fiber layer thickness, there was a significant (P = .0007) difference between operators in one eye. Peripapillary retinal nerve fiber layer thickness assessments using optical coherence tomography have good intraoperator and interoperator reproducibility. Inexperienced operators can generate useful measurement data with acceptable levels of variance.

Axonal transport rate decreased at the onset of optic neuritis in EAE mice

PubMed Central

Lin, Tsen-Hsuan; Kim, Joong Hee; Perez-Torres, Carlos; Chiang, Chia-Wen; Trinkaus, Kathryn; Cross, Anne H.; Song, Sheng-Kwei

2014-01-01

Optic neuritis is frequently the first symptom of multiple sclerosis (MS), an inflammatory demyelinating neurodegenerative disease. Impaired axonal transport has been considered as an early event of neurodegenerative diseases. However, few studies have assessed the integrity of axonal transport in MS or its animal models. We hypothesize that axonal transport impairment occurs at the onset of optic neuritis in experimental autoimmune encephalomyelitis (EAE) mice. In this study, we employed manganese-enhanced MRI (MEMRI) to assess axonal transport in optic nerves in EAE mice at the onset of optic neuritis. Axonal transport was assessed as (a) optic nerve Mn2+ accumulation rate (in % signal change/hour) by measuring the rate of increased total optic nerve signal enhancement, and (b) Mn2+ transport rate (in mm/hour) by measuring the rate of change in optic nerve length enhanced by Mn2+. Compared to sham-treated healthy mice, Mn2+ accumulation rate was significantly decreased by 19% and 38% for EAE mice with moderate and severe optic neuritis, respectively. The axonal transport rate of Mn2+ was significantly decreased by 43% and 65% for EAE mice with moderate and severe optic neuritis, respectively. The degree of axonal transport deficit correlated with the extent of impaired visual function and diminished microtubule-associated tubulins, as well as the severity of inflammation, demyelination, and axonal injury at the onset of optic neuritis. PMID:24936685

Gross Anatomical Study of the Nerve Supply of Genitourinary Structures in Female Mongrel Hound Dogs

PubMed Central

Gomez-Amaya, S. M.; Ruggieri, M. R.; Arias Serrato, S. A.; Massicotte, V. S.; Barbe, M. F.

2014-01-01

Summary Anatomical variations in lumbosacral plexus or nerves to genitourinary structures in dogs are under described, despite their importance during surgery and potential contributions to neuromuscular syndromes. Gross dissection of 16 female mongrel hound dogs showed frequent variations in lumbosacral plexus classification, sympathetic ganglia, ventral rami input to nerves innervating genitourinary structures and pudendal nerve (PdN) branching. Lumbosacral plexus classification types were mixed, rather than pure, in 13 (82%) of dogs. The genitofemoral nerve (GFN) originated from ventral ramus of L4 in 67% of nerves, differing from the expected L3. Considerable variability was seen in ventral rami origins of pelvic (PN) and Pd nerves, with new findings of L7 contributions to PN, joining S1 and S2 input (23% of sides in 11 dogs) or S1–S3 input (5%), and to PdN, joining S1–S2, unilaterally, in one dog. L7 input was confirmed using retrograde dye tracing methods. The PN also received CG1 contributions, bilaterally, in one dog. The PdN branched unusually in two dogs. Lumbosacral sympathetic ganglia had variant intra-, inter- and multisegmental connectivity in 6 (38%). Thus, the anatomy of mongrel dogs had higher variability than previously described for purebred dogs. Knowledge of this variant innervation during surgery could aid in the preservation of nerves and reduce risk of urinary and sexual dysfunctions. PMID:24730986

Prognostic significance of electrophysiological tests for facial nerve outcome in vestibular schwannoma surgery.

PubMed

van Dinther, J J S; Van Rompaey, V; Somers, T; Zarowski, A; Offeciers, F E

2011-01-01

To assess the prognostic significance of pre-operative electrophysiological tests for facial nerve outcome in vestibular schwannoma surgery. Retrospective study design in a tertiary referral neurology unit. We studied a total of 123 patients with unilateral vestibular schwannoma who underwent microsurgical removal of the lesion. Nine patients were excluded because they had clinically abnormal pre-operative facial function. Pre-operative electrophysiological facial nerve function testing (EPhT) was performed. Short-term (1 month) and long-term (1 year) post-operative clinical facial nerve function were assessed. When pre-operative facial nerve function, evaluated by EPhT, was normal, the outcome from clinical follow-up at 1-month post-operatively was excellent in 78% (i.e. HB I-II) of patients, moderate in 11% (i.e. HB III-IV), and bad in 11% (i.e. HB V-VI). After 1 year, 86% had excellent outcomes, 13% had moderate outcomes, and 1% had bad outcomes. Of all patients with normal clinical facial nerve function, 22% had an abnormal EPhT result and 78% had a normal result. No statistically significant differences could be observed in short-term and long-term post-operative facial function between the groups. In this study, electrophysiological tests were not able to predict facial nerve outcome after vestibular schwannoma surgery. Tumour size remains the best pre-operative prognostic indicator of facial nerve function outcome, i.e. a better outcome in smaller lesions.

Ursolic acid induces neural regeneration after sciatic nerve injury

PubMed Central

Liu, Biao; Liu, Yan; Yang, Guang; Xu, Zemin; Chen, Jiajun

2013-01-01

In this study, we aimed to explore the role of ursolic acid in the neural regeneration of the injured sciatic nerve. BALB/c mice were used to establish models of sciatic nerve injury through unilateral sciatic nerve complete transection and microscopic anastomosis at 0.5 cm below the ischial tube-rosity. The successfully generated model mice were treated with 10, 5, or 2.5 mg/kg ursolic acid via intraperitoneal injection. Enzyme-linked immunosorbent assay results showed that serum S100 protein expression level gradually increased at 1–4 weeks after sciatic nerve injury, and significantly decreased at 8 weeks. As such, ursolic acid has the capacity to significantly increase S100 protein expression levels. Real-time quantitative PCR showed that S100 mRNA expression in the L4–6 segments on the injury side was increased after ursolic acid treatment. In addition, the muscular mass index in the soleus muscle was also increased in mice treated with ursolic acid. Toluidine blue staining revealed that the quantity and average diameter of myelinated nerve fibers in the injured sciatic nerve were significantly increased after treatment with ursolic acid. 10 and 5 mg/kg of ursolic acid produced stronger effects than 2.5 mg/kg of ursolic acid. Our findings indicate that ursolic acid can dose-dependently increase S100 expression and promote neural regeneration in BALB/c mice following sciatic nerve injury. PMID:25206561

Optic nerve head drusen and idiopathic intracranial hypertension in a 14-year-old girl.

PubMed

Granger, Robert H; Bonnelame, Thomas; Daubenton, John; Dreyer, Michael; McCartney, Paul

2009-01-01

A 14-year-old girl had a 3-month history of headache and blurred vision. Funduscopy showed bilateral optic disc edema. Findings on brain imaging were normal, and a diagnosis of idiopathic intracranial hypertension was confirmed after lumbar puncture showed an elevated opening pressure of 32 cm H(2)O. Optic nerve head drusen were noted on computed tomography scan and confirmed with B-scan ultrasound. After 2 years, resolution of symptoms coincided with variable compliance to treatment with acetazolamide and concomitant papilledema. In general, optic disc edema poses a clinical conundrum due to the more common occurrence of optic nerve head drusen, potentially resulting in delayed diagnosis and treatment of idiopathic intracranial hypertension. Copyright 2009, SLACK Incorporated.

Optical coherence tomography platforms and parameters for glaucoma diagnosis and progression.

PubMed

Mwanza, Jean-Claude; Budenz, Donald L

2016-03-01

Optical coherence tomography (OCT) aids in the diagnosis and long-term monitoring of various ocular diseases, including glaucoma. Initially, the retinal nerve fiber layer was the only OCT structural parameter used in glaucoma. Subsequent research has resulted in more retinal and optic nerve head parameters. In addition, OCT is being investigated for its ability to assess ocular hemodynamics. This review summarizes these spectral domain-optical coherence tomography (SDOCT) parameters in the context of glaucoma. Several new SDOCT retinal nerve fiber layer, optic nerve head, and macular parameters with good glaucoma diagnostic ability have been added to existing ones recently. The combination of SDOCT and Doppler or angiography has also resulted in hemodynamic parameters that may prove to be useful in the functional assessment in glaucoma. OCT technology is advancing not only as a tool for structural assessment, but also as a multimodality tool to assess both structure and function to enhance our understanding of glaucoma, and ultimately clinical decisions.

Optic Nerve Atrophy Due to Long-Standing Compression by Planum Sphenoidale Meningioma.

PubMed

Di Somma, Alberto; Kaen, Ariel Matias; Cárdenas Ruiz-Valdepeñas, Eugenio; Cavallo, Luigi Maria

2018-05-01

In this study we report an uncommon endoscopic endonasal image of an atrophic optic nerve as seen after surgical removal of a suprasellar meningioma. The peculiarity of this case is the long-lasting underestimated ocular symptomatology of the patient who reported a 15-year history of impairment of vision on her left eye. A 51-year-old woman was admitted to our hospital complaining of a 15-year history of impairment of vision on her left eye. After making serendipitously the diagnosis of a suprasellar mass, we performed endoscopic endonasal surgery. The tumor was reached from below and removed safely, without manipulation of the optic pathways. At the end of tumor removal, the impressive left optic nerve atrophy due to enduring local tumor compression was visualized. To the best of our knowledge, no endoscopic endonasal image with such features has been provided in the pertinent literature. Possibly, this contribution will help identify damaged optic nerves during endoscopic endonasal surgery. Copyright © 2018 Elsevier Inc. All rights reserved.

Multi-modality imaging findings of huge intrachoroidal cavitation and myopic peripapillary sinkhole.

PubMed

Chen, Yutong; Ma, Xiaoli; Hua, Rui

2018-02-02

Peripapillary intrachoroidal cavitation was described as the presence of an asymptomatic, well-circumscribed, yellow-orange, peripapillary lesion at the inferior border of the myopic conus in eyes with high myopia. A 66-year-old myopic Chinese man was enrolled and his multi-color imaging examination showed a well-circumscribed, caesious, peripapillary lesion coalesced with the optic nerve head vertically rotated and obliquely tilted, together with an inferotemporal sinkhole in the myopic conus. The optical coherence tomography images showed an intrachoroidal hyporeflective space, schisis, an intracavitary septum located below the retinal pigment epithelium and inserted beneath the optic nerve head, as well as a sinkhole between the peripapillary intrachoroidal cavitation and the vitreous space. Both myopic colobomas and sinkhole in myopic conus may contribute the coalescence of intrachoroidal cavitation with optic nerve head. These qualitative and quantitative new findings will be beneficial for understanding its pathomorphological mechanism, and the impact on optic nerve tissue of myopic patients.

Ultrastructure of the extracellular matrix of bovine dura mater, optic nerve sheath and sclera.

PubMed Central

Raspanti, M; Marchini, M; Della Pasqua, V; Strocchi, R; Ruggeri, A

1992-01-01

The sclera, the outermost sheath of the optic nerve and the dura mater have been investigated histologically and ultrastructurally. Although these tissues appear very similar under the light microscope, being dense connective tissues mainly composed of collagen bundles and a limited amount of cells and elastic fibres, they exhibit subtle differences on electron microscopy. In the dura and sclera collagen appears in the form of large, nonuniform fibrils, similar to those commonly found in tendons, while in the optic nerve sheath the fibrils appear smaller and uniform, similar to those commonly observed in reticular tissues, vessel walls and skin. Freeze-fracture also reveals these fibrils to have different subfibrillar architectures, straight or helical, which correspond to 2 distinct forms of collagen fibril previously described (Raspanti et al. 1989). The other extracellular matrix components also vary with the particular collagen fibril structure. Despite their common embryological derivation, the dura mater, optic nerve sheath and sclera exhibit diversification of their extracellular matrix consistent with the mechanical loads to which these tissues are subjected. Our observations indicate that the outermost sheath of the optic nerve resembles the epineurium of peripheral nerves rather than the dura to which it is commonly likened. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:1295858

Stem Cell Ophthalmology Treatment Study (SCOTS): bone marrow-derived stem cells in the treatment of Leber's hereditary optic neuropathy

PubMed Central

Weiss, Jeffrey N.; Levy, Steven; Benes, Susan C.

2016-01-01

The Stem Cell Ophthalmology Treatment Study (SCOTS) is currently the largest-scale stem cell ophthalmology trial registered at ClinicalTrials.gov (identifier: NCT01920867). SCOTS utilizes autologous bone marrow-derived stem cells (BMSCs) to treat optic nerve and retinal diseases. Treatment approaches include a combination of retrobulbar, subtenon, intravitreal, intra-optic nerve, subretinal, and intravenous injection of autologous BMSCs according to the nature of the disease, the degree of visual loss, and any risk factors related to the treatments. Patients with Leber's hereditary optic neuropathy had visual acuity gains on the Early Treatment Diabetic Retinopathy Study (ETDRS) of up to 35 letters and Snellen acuity improvements from hand motion to 20/200 and from counting fingers to 20/100. Visual field improvements were noted. Macular and optic nerve head nerve fiber layer typically thickened. No serious complications were seen. The increases in visual acuity obtained in our study were encouraging and suggest that the use of autologous BMSCs as provided in SCOTS for ophthalmologic mitochondrial diseases including Leber's hereditary optic neuropathy may be a viable treatment option. PMID:27904503

Retinotopic and temporal organization of the optic nerve and tracts in the adult goldfish.

PubMed

Bunt, S M

1982-04-10

In order to investigate the role of the different factors controlling the pathways and termination sites of growing axons, selected optic fibers were traced from the eye to the tectum in adult goldfish either by filling them with HRP, or by severing a group of fibers and tracing their degeneration in 2 micrometers plastic sections stained with toluidine blue. Some fish received more than one lesion and others received both lesions and HRP applications. Two major rearrangements of the optic fibers were identified, one at the exit from the eye, the other within the optic tracts. Near the eye the optic fibers appear to be guided by the conformation of the underlying tissue planes that they encounter. The most recently added fibers, from the peripheral retina, grow over the vitread surface of the older fibers toward the blood vessel in the center of the optic nerve head. Behind the eye the fibers follow this blood vessel until it leaves the side of the optic nerve, and the fibers from peripheral retina are left as a single group on the ventral edge of the optic nerve cross section. As a consequence of this pattern of fiber growth the fibers form an orderly temporal sequence in the optic nerve, with the oldest fibers from the central retina on one side of the nerve and the youngest from peripheral retina on the other. In addition, the fibers are ordered topographically at right angles to this central-to-peripheral axis, with fibers from ventral retina on each edge of the nerve, dorsal fibers in the center, and nasal and temporal fibers in between. This arrangement of the optic fibers continues with only a little loss of precision up to the optic tracts. A more radical fiber rearrangement, seemingly incompatible with the fibers simply following tissue planes occurs within the optic tracts. Each newly arriving set of fibers grows over the surface of the optic tracts so that the older fibers come to lie deepest in the tracts. This segregation of fibers of different ages ensures that the rearrangement is limited to each layer of fibers. The abrupt reorganization of the fibers occurs as the tracts split around the nucleus rotundus to form the brachia of the optic tracts. The fibers are then arranged with temporal fibers nearest the nucleus rotundus and nasal fibers on the opposite edges of the brachia. From this point the fibers grow out over the tectal surface to their termination sites with only minimal rearrangements. Therefore the optic fiber rearrangements show evidence of several different sorts of constraints acting on the fibers at separate points in the optic pathway, each contributing to the final orderly arrangement of the fibers on the optic tectum.

Macular retinal and choroidal thickness in unilateral amblyopia using swept-source optical coherence tomography.

PubMed

Araki, Syunsuke; Miki, Atsushi; Goto, Katsutoshi; Yamashita, Tsutomu; Takizawa, Go; Haruishi, Kazuko; Ieki, Yoshiaki; Kiryu, Junichi; Yaoeda, Kiyoshi

2017-09-15

To investigate macular retinal and choroidal thickness in amblyopic eyes compared to that in fellow and normal eyes using swept-source optical coherence tomography (SS-OCT). This study examined 31 patients with hyperopic anisometropic amblyopia (6.9 ± 3.8 years, mean ± standard deviation), 15 patients with strabismic amblyopia without anisometropia (7.9 ± 4.2 years), and 24 age-matched controls (7.8 ± 3.3 years). Retinal and choroidal thickness was measured by 3D scans using SS-OCT. A 6-mm area around the fovea was automatically analyzed using the Early Treatment Diabetic Retinopathy Study map. The thickness from SS-OCT was corrected for magnification error using individual axial length, spherical refraction, cylinder refraction, and corneal radius. Retinal thickness was divided into the macular retinal nerve fiber layer (mRNFL), ganglion cell layer + inner plexiform layer (GCL+IPL), ganglion cell complex (GCC), and the inner limiting membrane to the retinal pigment epithelium (ILM-RPE) thickness. Retinal and choroidal thickness was compared among amblyopic, fellow, and normal eyes. In both amblyopia groups, there was no significant difference in the mRNFL, GCL+IPL, and GCC thicknesses among the amblyopic, fellow, and control eyes. In the anisometropic amblyopia group, choroidal thickness (subfovea, center 1 mm, nasal and inferior of the inner ring, nasal of the outer ring, and center 6 mm) of amblyopic eyes were significantly greater than that of fellow and normal eyes. In contrast, none of the choroidal thicknesses were significantly different among the investigated eyes in the strabismic amblyopia group. We found no significant difference in inner retinal thickness in patients with unilateral amblyopia. Although there were significant differences in choroidal thickness with hyperopic anisometropic amblyopia, there was no significant difference for the strabismic amblyopia. The discrepancy in choroidal thickness between the two types of amblyopia may be due to both differences in ocular size and underlying mechanism.

Modeling the action-potential-sensitive nonlinear-optical response of myelinated nerve fibers and short-term memory

NASA Astrophysics Data System (ADS)

Shneider, M. N.; Voronin, A. A.; Zheltikov, A. M.

2011-11-01

The Goldman-Albus treatment of the action-potential dynamics is combined with a phenomenological description of molecular hyperpolarizabilities into a closed-form model of the action-potential-sensitive second-harmonic response of myelinated nerve fibers with nodes of Ranvier. This response is shown to be sensitive to nerve demyelination, thus enabling an optical diagnosis of various demyelinating diseases, including multiple sclerosis. The model is applied to examine the nonlinear-optical response of a three-neuron reverberating circuit—the basic element of short-term memory.

Torsion Induced Traumatic Optic Neuropathy (TITON): Animal Model for Diagnostics, Drugs Delivery, and Therapeutics for Injuries to the Cental Nervous System

DTIC Science & Technology

2016-06-01

neck and the eye coils are actively decoupled. The following parameters will be used: slice thickness = 1 mm, TR = 4 s, TE = 13 ms, label duration... Eyes were removed with 3-5 mm of optic nerve intact taking care not to stretch or otherwise injure the nerve. Eyes were flash frozen in liquid...nitrogen, then stored at -80°C. The eyes were then sectioned through the optic nerve using a cryostat, then transferred to indium titanium oxide-coated

Autosomal dominant optic nerve colobomas, vesicoureteral reflux, and renal anomalies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schimmenti, L.A.; Pierpont, M.E.; Carpenter, B.L.M.

1995-11-06

We describe a father and 3 sons with optic nerve colobomas, vesicoureteral reflux, and renal anomalies. The youngest son had congenital renal failure and ultimately underwent renal transplantation. The father and one son had high frequency hearing loss. There were no other affected relatives. We conclude that the association of optic nerve colobomas, renal anomalies, and vesicoureteral reflux comprises a unique autosomal dominant syndrome. Molecular investigations have determined this disorder to be associated with a single nucleotide deletion in the PAX2 gene. 16 refs., 3 figs.

Moebius syndrome with Dandy-Walker variant and agenesis of corpus callosum.

PubMed

John, Jomol Sara; Vanitha, R

2013-09-01

Moebius syndrome is a rare congenital neurological disorder. The most frequent mode of presentation is facial diplegia with bilateral lateral rectus palsy, but there are variations. Here, we report a rare case of Moebius syndrome in a 15-month-old child with unilateral facial palsy, bilateral abducens nerve palsy with Dandy Walker variant, and complete agenesis of corpus callosum.

Blink Prosthesis For Facial Paralysis Patients

DTIC Science & Technology

2016-10-01

predisposes patients to corneal exposure and dry eye complications that are difficult to effectively treat. The proposed innovation will provide a...aesthetic and functional use of the paralyzed eyelid by preventing painful dry eye complications and profound facial disfiguration. The goal of this program... eye blink in patients with unilateral facial nerve paralysis. The system will electrically stimulate the paretic eyelid when EMG electrodes detect

Bell's Palsy as a Possible Complication of Hepatitis B Vaccination in A Child

PubMed Central

Tan, Hüseyin; Orbak, Zerrin

2009-01-01

Bell's Palsy is the sudden onset of unilateral temporary paralysis of facial muscles resulting from seventh cranial nerve dysfunction. Presented here is a two-year old female patient with right peripheral facial palsy following hepatitis B vaccination. Readers’ attention is drawn to an uncommon cause of Bell's Palsy, as a rare complication of hepatitis B vaccination. PMID:19902808

Suppression of Tinnitus in a Patient with Unilateral Sudden Hearing Loss: A Case Report

PubMed Central

Fioretti, Alessandra; Peri, Giorgia; Eibenstein, Alberto

2012-01-01

We describe a case of a 67-year-old woman with severe disabling right-sided tinnitus, mild hyperacusis, and headache. The tinnitus was associated with sudden right hearing loss and vertigo, which occurred about 18 months before. Magnetic resonance imaging (MRI) resulted in normal anatomical structures of the cochlea and of the cranial nerves showing a partial empty sella syndrome with suprasellar cistern hernia. Angio-MR revealed a bilateral contact between the anterior-inferior cerebellar artery (AICA) and the acoustic-facial nerve with a potential neurovascular conflict. Surgery was considered unnecessary after further evaluations. The right ear was successfully treated with a combination device (hearing aid plus sound generator). Shortly after a standard fitting procedure, the patient reported a reduction of tinnitus, hyperacusis, and headache which completely disappeared at the follow-up evaluation after 3, 6, and 12 months. This paper demonstrates that the combination device resulted in a complete tinnitus and hyperacusis suppression in a patient with unilateral sensorineural sudden hearing loss. Our paper further supports the restoration of peripheral sensory input for the treatment of tinnitus associated with hearing loss in selected patients. PMID:23227400

Ansa-RLN reinnervation for unilateral vocal fold paralysis in adolescents and young adults.

PubMed

Smith, Marshall E; Roy, Nelson; Stoddard, Kelly

2008-09-01

To assess the outcomes of management of unilateral vocal fold paralysis by ansa-RLN reinnervation in a series of patients ages 12-21. Clinical outcomes study. Six consecutive adolescents and young adults (ages 12-21 years) seeking treatment for unilateral vocal fold paralysis and glottal incompetence underwent ansa-RLN neurorraphy. Pre- and post-operative voice recordings acquired at least 1 year following surgery were submitted to acoustic and perceptual analysis. Patient-based measures were also taken. Mean perceptual visual analogue scale rating of dysphonia severity (0mm=profoundly abnormal voice, 100mm=completely normal voice) improved from 50mm pre-operatively to 82mm post-operatively. Mean maximum phonation time improved from 6.5s to 13.2s. Pitch and dynamic range were also observed to improve. Global self-ratings of voice function (0-100%) increased from 31.2% to 81.6% of normal. Ansa-RLN reinnervation is an effective treatment option for adolescents and young adults with unilateral vocal fold paralysis. The procedure has the potential to improve vocal function substantially, especially in those with isolated paralysis of the recurrent laryngeal nerve. The procedure alleviates the disadvantages associated with other surgical options for this age group.

Evaluation of Eyeball and Orbit in Relation to Gender and Age.

PubMed

Özer, Cenk Murat; Öz, Ibrahim Ilker; Şerifoğlu, Ismail; Büyükuysal, Mustafa Çağatay; Barut, Çağatay

2016-11-01

The orbital aperture is the entrance to the orbit in which most important visual structures such as the eyeball and the optic nerve are found. It is vital not only for the visual system but also for the evaluation and recognition of the face. Eyeball volume is essential for diagnosing microphthalmos or buphthalmos in several eye disorders. Knowing the length of the optic nerve is necessary in selecting the right instruments for enucleation. Therefore, the aim of this study was to evaluate eyeball volume, orbital aperture, and optic nerve dimensions for a morphological description in a Turkish population sample according to gender and body side.Paranasal sinus computed tomography (CT) scans of 198 individuals (83 females, 115 males) aged between 5 and 74 years were evaluated retrospectively. The dimensions of orbital aperture, axial length and volume of eyeball, and diameter and length of the intraorbital part of the optic nerve were measured. Computed tomography examinations were performed on an Activion 16 CT Scanner (Toshiba Medical Systems, 2008 Japan). The CT measurements were calculated by using OsiriX software on a personal computer. All parameters were evaluated according to gender and right/left sides. A statistically significant difference between genders was found with respect to axial length of eyeball, optic nerve diameter, dimensions of orbital aperture on both sides, and right optic nerve length. Furthermore, certain statistically significant side differences were also found. There were statistically significant correlations between age and the axial length of the eyeball, optic nerve diameter, and the transverse length of the orbital aperture on both sides for the whole study group.In this study we determined certain morphometric parameters of the orbit. These outcomes may be helpful in developing a database to determine normal orbit values for the Turkish population so that quantitative assessment of orbital disease and orbital deformities will be evaluated both for preoperative planning and for assessing postoperative outcomes.

Peripheral nerve reconstruction with epsilon-caprolactone conduits seeded with vasoactive intestinal peptide gene-transfected mesenchymal stem cells in a rat model

NASA Astrophysics Data System (ADS)

Hernández-Cortés, P.; Toledo-Romero, M. A.; Delgado, M.; Sánchez-González, C. E.; Martin, F.; Galindo-Moreno, P.; O'Valle, F.

2014-08-01

Objective. Attempts have been made to improve nerve conduits in peripheral nerve reconstruction. We investigated the potential therapeutic effect of a vasoactive intestinal peptide (VIP), a neuropeptide with neuroprotective, trophic and developmental regulatory actions, in peripheral nerve regeneration in a severe model of nerve injury that was repaired with nerve conduits. Approach. The sciatic nerve of each male Wistar rat was transected unilaterally at 10 mm and then repaired with Dl-lactic-ɛ-caprolactone conduits. The rats were treated locally with saline, with the VIP, with adipose-derived mesenchymal stem cells (ASCs) or with ASCs that were transduced with the VIP-expressing lentivirus. The rats with the transected nerve, with no repairs, were used as untreated controls. At 12 weeks post-surgery, we assessed their limb function by measuring the ankle stance angle and the percentage of their muscle mass reduction, and we evaluated the histopathology, immunohistochemistry and morphometry of the myelinated fibers. Main results. The rats that received a single injection of VIP-expressing ASCs showed a significant functional recovery in the ankle stance angle (p = 0.049) and a higher number of myelinated fibers in the middle and distal segments of the operated nerve versus the other groups (p = 0.046). Significance. These results suggest that utilization of a cellular substrate, plus a VIP source, is a promising method for enhancing nerve regeneration using Dl-lactic-ɛ-caprolactone conduits and that this method represents a potential useful clinical approach to repairing peripheral nerve damage.

Correlation between retinal nerve fibre layer thickness and optic nerve head size: an optical coherence tomography study.

PubMed

Savini, G; Zanini, M; Carelli, V; Sadun, A A; Ross-Cisneros, F N; Barboni, P

2005-04-01

To investigate the correlation between retinal nerve fibre layer (RNFL) thickness and optic nerve head (ONH) size in normal white subjects by means of optical coherence tomography (OCT). 54 eyes of 54 healthy subjects aged between 15 and 54 underwent peripapillary RNFL thickness measurement by a series of three circular scans with a 3.4 mm diameter (Stratus OCT, RNFL Thickness 3.4 acquisition protocol). ONH analysis was performed by means of six radial scans centred on the optic disc (Stratus OCT, Fast Optic Disc acquisition protocol). The mean RNFL values were correlated with the data obtained by ONH analysis. The superior, nasal, and inferior quadrant RNFL thickness showed a significant correlation with the optic disc area (R = 0.3822, p = 0.0043), (R = 0.3024, p = 0.026), (R = 0.4048, p = 0.0024) and the horizontal disc diameter (R = 0.2971, p = 0.0291), (R = 0.2752, p = 0.044), (R = 0.3970, p = 0.003). The superior and inferior quadrant RNFL thickness was also positively correlated with the vertical disc diameter (R = 0.3774, p = 0.0049), (R = 0.2793, p = 0.0408). A significant correlation was observed between the 360 degrees average RNFL thickness and the optic disc area and the vertical and horizontal disc diameters of the ONH (R = 0.4985, p = 0.0001), (R = 0.4454, p = 0.0007), (R = 0.4301, p = 0.0012). RNFL thickness measurements obtained by Stratus OCT increased significantly with an increase in optic disc size. It is not clear if eyes with large ONHs show a thicker RNFL as a result of an increased amount of nerve fibres or to the shorter distance between the circular scan and the optic disc edge.

A common-path optical coherence tomography based electrode for structural imaging of nerves and recording of action potentials

NASA Astrophysics Data System (ADS)

Islam, M. Shahidul; Haque, Md. Rezuanul; Oh, Christian M.; Wang, Yan; Park, B. Hyle

2013-03-01

Current technologies for monitoring neural activity either use different variety of electrodes (electrical recording) or require contrast agents introduced exogenously or through genetic modification (optical imaging). Here we demonstrate an optical method for non-contact and contrast agent free detection of nerve activity using phase-resolved optical coherence tomography (pr-OCT). A common-path variation of the pr-OCT is recently implemented and the developed system demonstrated the capability to detect rapid transient structural changes that accompany neural spike propagation. No averaging over multiple trials was required, indicating its capability of single-shot detection of individual impulses from functionally stimulated Limulus optic nerve. The strength of this OCT-based optical electrode is that it is a contactless method and does not require any exogenous contrast agent. With further improvements in accuracy and sensitivity, this optical electrode will play a complementary role to the existing recording technologies in future.

[Flicker comparison of optic disc photographs: sensitivity and specificity].

PubMed

Funk, Jens; Lagrèze, Wolf; Zeyen, Thierry

2002-12-01

Examination and documentation of the optic nerve head are essential in monitoring glaucoma patients. Even minor changes in optic nerve head morphology can be visualised using the so-called flicker test: Two optic nerve head photographs, taken at consecutive examinations, are superimposed by projection. When occluding the pictures in a rapid alternating fashion, changes in optic nerve head morphology appear as motion. In this study, we evaluated sensitivity and specificity of the flicker test. A set of 33 pairs of serial optic disc slides was used as gold standard. These 33 pairs had been classified earlier by 3 independent groups of experts. 23 had been classified as "no change over time", 10 had been classified as "change". All 33 pairs were now evaluated by flicker comparison in a masked fashion. Flicker comparison usually took 1 minute per pair of slides. Sensitivity was 90 %, specificity was 65 %. The sensitivity was reasonably high. The moderate specificity was due to some cases showing "change" with the flicker comparison which might have been overlooked by the expert groups. Flicker comparison is an easy, fast and reliable technique to evaluate pairs of consecutive optic disc photographs.

Hearing loss and enlarged internal auditory canal in children.

PubMed

Santos, Saturnino; Domínguez, M Jesús; Cervera, Javier; Suárez, Alicia; Bueno, Antonio; Bartolomé, Margarita; López, Rafael

2014-01-01

Among the temporal bone abnormalities that can be found in the etiological study of paediatric sensorineural hearing loss (SNHL) by imaging techniques, those related to the internal auditory canal (IAC) are the least frequent. The most prevalent of these abnormalities that is associated with SNHL is stenotic IAC due to its association with cochlear nerve deficiencies. Less frequent and less concomitant with SNHL is the finding of an enlarged IAC (>8mm). Retrospective and descriptive review of clinical associations, imaging, audiological patterns and treatment of 9 children with hearing loss and enlarged IAC in the period 1999 to 2012. Two groups of patients are described. The first, without association with vestibulocochlear dysplasias, consisted of: 2 patients with SNHL without other temporal bone or systemic abnormalities, one with bilateral mixed HL from chromosome 18q deletion, one with a genetic X-linked DFN3 hearing loss, one with unilateral hearing loss in neurofibromatosis type 2 with bilateral acoustic neuroma, and one with unilateral hearing loss with cochlear nerve deficiency. The second group, with association with vestibulocochlear dysplasias, was comprised of: one patient with moderate bilateral mixed hearing loss in branchio-oto-renal syndrome, one with profound unilateral SNHL with recurrent meningitis, and another with profound bilateral SNHL with congenital hypothyroidism. The presence of an enlarged IAC in children can be found in different clinical and audiological settings with relevancies that can range from life-threatening situations, such as recurrent meningitis, to isolated hearing loss with no other associations. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Virtual Instrumentation for a Fiber-Optics-Based Artificial Nerve

NASA Technical Reports Server (NTRS)

Lyons, Donald R.; Kyaw, Thet Mon; Griffin, DeVon (Technical Monitor)

2001-01-01

A LabView-based computer interface for fiber-optic artificial nerves has been devised as a Masters thesis project. This project involves the use of outputs from wavelength multiplexed optical fiber sensors (artificial nerves), which are capable of producing dense optical data outputs for physical measurements. The potential advantages of using optical fiber sensors for sensory function restoration is the fact that well defined WDM-modulated signals can be transmitted to and from the sensing region allowing networked units to replace low-level nerve functions for persons desirous of "intelligent artificial limbs." Various FO sensors can be designed with high sensitivity and the ability to be interfaced with a wide range of devices including miniature shielded electrical conversion units. Our Virtual Instrument (VI) interface software package was developed using LabView's "Laboratory Virtual Instrument Engineering Workbench" package. The virtual instrument has been configured to arrange and encode the data to develop an intelligent response in the form of encoded digitized signal outputs. The architectural layout of our nervous system is such that different touch stimuli from different artificial fiber-optic nerve points correspond to gratings of a distinct resonant wavelength and physical location along the optical fiber. Thus, when an automated, tunable diode laser sends scans, the wavelength spectrum of the artificial nerve, it triggers responses that are encoded with different touch stimuli by way wavelength shifts in the reflected Bragg resonances. The reflected light is detected and a resulting analog signal is fed into ADC1 board and DAQ card. Finally, the software has been written such that the experimenter is able to set the response range during data acquisition.

Review: Tauopathy in the retina and optic nerve: does it shadow pathological changes in the brain?

PubMed Central

Ho, Wing-Lau; Leung, Yen; Tsang, Andrea Wing-Ting; So, Kwok-Fai; Chiu, Kin

2012-01-01

Tau protein’s versatility lies in its functions within the central nervous system, including protein scaffolding and intracellular signaling. Tauopathy has been one of the most extensively studied neuropathologies among the neurodegenerative diseases. Because the retina and optic nerve are parts of the central nervous system, we hypothesize that tauopathy also plays a role in various eye diseases. However, little is known about tauopathy in the retina and optic nerve. Here, we summarize the findings from histopathological studies on animal models and human specimens with distinct neurodegenerative diseases. Similar pathological changes of tau protein can be found in Alzheimer’s disease, frontotemporal lobe dementia, and glaucoma. In view of the important roles of tauopathy in the brain, it is hoped that this review can stimulate research on eye diseases of the retina and optic nerve. PMID:23170062

Wavelet denoising during optical coherence tomography of the prostate nerves using the complex wavelet transform.

PubMed

Chitchian, Shahab; Fiddy, Michael; Fried, Nathaniel M

2008-01-01

Preservation of the cavernous nerves during prostate cancer surgery is critical in preserving sexual function after surgery. Optical coherence tomography (OCT) of the prostate nerves has recently been studied for potential use in nerve-sparing prostate surgery. In this study, the discrete wavelet transform and complex dual-tree wavelet transform are implemented for wavelet shrinkage denoising in OCT images of the rat prostate. Applying the complex dual-tree wavelet transform provides improved results for speckle noise reduction in the OCT prostate image. Image quality metrics of the cavernous nerves and signal-to-noise ratio (SNR) were improved significantly using this complex wavelet denoising technique.

The effect of severity of unilateral vestibular dysfunction on symptoms, disabilities and handicap in vertiginous patients.

PubMed

Bamiou, D E; Davies, R A; McKee, M; Luxon, L M

1999-02-01

This study compares the symptoms, disabilities and handicap, as assessed by means of a questionnaire, in two groups of patients with a unilateral peripheral vestibular disorder: those with a total canal paresis and those with a partial canal paresis, as judged by the duration parameter using the Fitzgerald Hallpike caloric test in the absence of optic fixation. The results of the study indicate that the severity of dizziness, the Dizziness Index (severity x frequency) and the overall level of disabilities related to visual vertigo are less severe in unilateral profound or total loss of vestibular function than in unilateral mild vestibular loss.

Choroidal thickness in Chinese patients with non-arteritic anterior ischemic optic neuropathy.

PubMed

Jiang, Libin; Chen, Lanlan; Qiu, Xiujuan; Jiang, Ran; Wang, Yaxing; Xu, Liang; Lai, Timothy Y Y

2016-08-31

Non-arteritic anterior ischemic optic neuropathy (NA-AION) is one of the most common types of ischemic optic neuropathy. Several recent studies suggested that abnormalities of choroidal thickness might be associated with NA-AION. The main objective of this case-control study was to evaluate whether choroidal thickness is an ocular risk factor for the development of NA-AION by evaluating the peripapillary and subfoveal choroidal thicknesses in affected Chinese patients. Forty-four Chinese patients with unilateral NA-AION were recruited and compared with 60 eyes of 60 normal age and refractive-error matched control subjects. Peripapillary and subfoveal choroidal thicknesses were measured by enhanced depth imaging optical coherence tomography. Choroidal thicknesses of eyes with NA-AION and unaffected fellow eyes were compared with normal controls. Choroidal thicknesses of NA-AION eyes with or without optic disc edema were also compared. The correlation between choroidal thickness and retinal nerve fiber layer (RNFL) thickness, logMAR best-corrected visual acuity (BCVA), and the mean deviation (MD) of Humphrey static perimetry in NA-AION eyes were analyzed. The peripapillary choroidal thicknesses at the nasal, nasal inferior and temporal inferior segments in NA-AION eyes with optic disc edema were significantly thicker compared with that of normal subjects (P < 0.05). There was no significant difference in the choroidal thicknesses between the unaffected fellow eyes of NA-AION patients and normal eyes of healthy controls; or between the NA-AION eyes with resolved optic disc edema and normal eyes (all P > 0.05). No significant correlation between choroidal thickness and RNFL thickness, logMAR BCVA and perimetry MD was found in eyes affected by NA-AION (all P > 0.05). Increase in peripapillary choroid thickness in some segments was found in NA-ION eyes with optic disc edema. However, our findings do not support the hypothesis that choroidal thickness is abnormal in Chinese patients with NA-AION compared with normal subjects with similar age and refractive error status.

Methods for determination of optic nerve blood flow.

PubMed Central

Glazer, L. C.

1988-01-01

A variety of studies have been conducted over the past two decades to determine if decreased optic nerve blood flow has a role in the etiology of glaucomatous nerve damage. Five basic methods have been employed in examining blood flow. Invasive studies, utilizing electrodes placed in the optic nerve head, represent one of the first attempts to measure blood flow. More recently, the methodologies have included axoplasmic flow analysis, microspheres, radioactive tracers such as iodoantipyrine, and laser doppler measurements. The results of these studies are inconclusive and frequently contradictory. When the studies are grouped by methodology, only the iodoantipyrine data are consistent. While each of the experimental techniques has limitations, iodoantipyrine appears to have better resolution than either invasive studies or microspheres. PMID:3284212

Decreased thickness of the lower trapezius muscle in patients with unilateral neck pain.

PubMed

Uthaikhup, Sureeporn; Pensri, Chalomjai; Kawsoiy, Kanokon

2016-09-01

Thickness of the lower trapezius muscle in patients with neck pain has not been established. We examined the thickness of the lower trapezius muscle in patients with and without unilateral neck pain. Twenty women with unilateral (right) neck pain and 20 matched controls participated in the study. Thickness of the lower trapezius muscles was measured bilaterally at rest (0 ° and 120 ° of shoulder abduction) and during contraction (120 ° of shoulder abduction) using ultrasound imaging. The neck pain group had smaller thickness of the lower trapezius muscle on the painful side compared with controls both at rest and during contraction (P < 0.05). However, the percentage change in the lower trapezius thickness from rest to contraction (120 ° of shoulder abduction) was not different between groups (P > 0.05). Patients with neck pain had smaller thickness of the lower trapezius muscle on the painful side compared with healthy controls. Muscle Nerve 54: 439-443, 2016. © 2015 Wiley Periodicals, Inc.

Vagus Nerve Stimulation Delivered During Motor Rehabilitation Improves Recovery in a Rat Model of Stroke

PubMed Central

Khodaparast, Navid; Hays, Seth A.; Sloan, Andrew M.; Fayyaz, Tabbassum; Hulsey, Daniel R.; Rennaker, Robert L.; Kilgard, Michael P.

2014-01-01

Neural plasticity is widely believed to support functional recovery following brain damage. Vagus nerve stimulation paired with different forelimb movements causes long-lasting map plasticity in rat primary motor cortex that is specific to the paired movement. We tested the hypothesis that repeatedly pairing vagus nerve stimulation with upper forelimb movements would improve recovery of motor function in a rat model of stroke. Rats were separated into three groups: vagus nerve stimulation during rehab, vagus nerve stimulation after rehab, and rehab alone. Animals underwent 4 training stages: shaping (motor skill learning), pre-lesion training, post-lesion training, and therapeutic training. Rats were given a unilateral ischemic lesion within motor cortex and implanted with a left vagus nerve cuff. Animals were allowed one week of recovery before post-lesion baseline training. During the therapeutic training stage, rats received vagus nerve stimulation paired with each successful trial. All seventeen trained rats demonstrated significant contralateral forelimb impairment when performing a bradykinesia assessment task. Forelimb function was recovered completely to pre-lesion levels when vagus nerve stimulation was delivered during rehab training. Alternatively, intensive rehab training alone (without stimulation) failed to restore function to pre-lesion levels. Delivering the same amount of stimulation after rehab training did not yield improvements compared to rehab alone. These results demonstrate that vagus nerve stimulation repeatedly paired with successful forelimb movements can improve recovery after motor cortex ischemia and may be a viable option for stroke rehabilitation. PMID:24553102

Changes in nerve conduction and Pi/PCr ratio during denervation-reinnervation of the gastrocsoleus muscles of rats

NASA Technical Reports Server (NTRS)

Lai, K. S.; Jaweed, M. M.; Seestead, R.; Herbison, G. J.; Ditunno, J. F. Jr; McCully, K.; Chance, B.

1992-01-01

The purpose of this investigation was to study the changes in nerve conduction and phosphate metabolites of the gastrocsoleus muscles of rats during denervation-reinnervation. Sixteen male Sprague-Dawley rats underwent unilateral crush-denervation of the left sciatic nerves at the sciatic notch. Six rats were used for measurement of motor conduction latency and action potential amplitude of the gastrocsoleus muscle by stimulating the sciatic nerve at one, two and eight weeks after nerve crush. The other ten rats were designated for evaluation of the ratio of inorganic phosphorous (Pi) to phosphocreatine (PCr) by a 31P-phosphoenergetic spectrometer at two weeks and eight weeks after nerve crush. None of the sciatic nerves showed conduction to the gastrocsoleus at one or two weeks after nerve crush. At eight weeks postcrush, the motor conduction latency returned to within normal limits, whereas the action potential amplitude was only 55% of the normal. For the eight-week period of study, the Pi/PCr ratio of the normal control muscles ranged between 0.09 +/- 0.02 and 0.11 +/- 0.02 (mean +/- SD). The denervated muscles showed an increase of Pi/PCr ratio by 54% at two weeks postcrush, compared to the respective contralateral control sides. The ratios returned to the normal value by eight weeks postcrush. In summary, these data suggested that the metabolic recovery of the crush-denervated muscle followed the same pattern as the parameters of nerve conduction.

Continuous-wave optical stimulation of the rat prostate nerves using an all-single-mode 1455 nm diode laser and fiber system

NASA Astrophysics Data System (ADS)

Tozburun, Serhat; Lagoda, Gwen A.; Burnett, Arthur L.; Fried, Nathaniel M.

2011-03-01

Optical nerve stimulation (ONS) has recently been reported as a potential alternative to electrical nerve stimulation. Continuous-wave (CW) laser stimulation of the prostate cavernous nerves (CN) in a rat model, in vivo, has also been demonstrated in our previous studies. The objective of this study is to present a new all-single-mode-fiber configuration for ONS with the laser operating in CW mode for potential diagnostic applications. An infrared pigtailed single-mode diode laser (λ = 1455 nm) was used in this study for noncontact ONS. This new all-fiber approach introduces several advantages including: (1) a less expensive and more compact ONS system, (2) elimination of alignment of optical components, and (3) an improved spatial beam profile. Successful optical stimulation of the rat CN using this new design was observed after the CN reached a threshold temperature of ~ 41 °C with response times as short as 3 s. Upon further study, this configuration may be useful for identification and preservation of the cavernous nerves during prostate cancer surgery.

The use of Peer Optic Nerve Photographs for Teaching Direct Ophthalmoscopy

PubMed Central

Milani, Behrad Y.; Majdi, Mercede N.; Green, Wesley; Mehralian, Amir; Moarefi, Majid; Oh, Freddie S.; Riddle, Janet M.; Djalilian, Ali R.

2014-01-01

Objective To use a novel teaching exercise to encourage students to practice ophthalmoscopy and to measure the learning effect both subjectively and objectively. Design Comparative case series. Participants One-hundred thirty-one fourth-year medical students on their one-week ophthalmology rotations with 89 in the experimental group and 42 in the control group. Methods Those in the experimental group had one eye dilated and their optic nerve photographed on the first day. The next day, these students received an unlabeled optic nerve photograph belonging to one of their peers (typically 8–10 per group) and were given three days to identify the student matching the photograph. The students in the control group were simply encouraged to practice ophthalmoscopy on each other without the use of photographs. Main Outcome Measures Both objective and subjective changes from the beginning to the end of the rotation were measured and compared between the two groups. Results In the 89 students who used peer optic nerve photographs, 75 (84.3%) showed improvement in direct ophthalmoscopy skills over the course of the week. In contrast, only 12 (28.6%) of the 42 control students demonstrated an objective improvement (P < 0.001). The subjective confidence levels were likewise more improved in the students who took part in the optic nerve photograph exercise. Conclusions These results suggest that the task of matching an unknown optic nerve photograph to the correct eye of a peer leads to increased self-confidence and more proficient use of the direct ophthalmoscope. PMID:23246117

Optic nerve involvement in a borderline lepromatous leprosy patient on multidrug therapy.

PubMed

Prabha, Neel; Mahajan, Vikram K; Sharma, Surinder K; Sharma, Vikas; Chauhan, Pushpinder S; Mehta, Karaninder S; Abhinav, C; Khatri, Gaytri; Chander, Bal; Tuli, Rajiv

2013-12-01

Amidst the plethora of ocular complications of leprosy, involvement of the posterior segment or optic nerve is extremely rare. The mechanism of optic neuritis in leprosy is poorly understood. A 47 year-old man presented with a single lesion suggestive of mid-borderline (BB) leprosy over left periorbital region; the histology showed borderline lepromatous (BL) leprosy with a BI of 3+. After initial improvement with WHO MDT-MB and prednisolone (40 mg/d) he developed sudden and painless diminished vision in the left eye, about 3 weeks later. His visual acuity was 6/9 in the left and 6/6 in the right eye, and there was left optic disc edema, hyperemia and blurred disc margins. Treatment with prednisolone (60 mg/d) along with WHO MDT-MB continued. A month later he returned with painless diminished vision in the other eye as well. Visual acuity was 6/6 in the right and 6/12 in the left eye, and there was right optic disc edema and left optic disc atrophy. CT of the head and MRI of the brain were normal. Inflammatory edema of the orbital connective tissue or other surrounding structures, or direct infiltration of vasa nervosa with resultant vascular occlusion leading to optic nerve ischemia, seems the most plausible explanation of optic nerve involvement in this case.

Assessing the changes in the spatial stiffness of the posterior sclera as a function of IOP with air-pulse OCE

NASA Astrophysics Data System (ADS)

Singh, Manmohan; Nair, Achuth; Aglyamov, Salavat R.; Wu, Chen; Han, Zhaolong; Lafon, Ericka; Larin, Kirill V.

2017-02-01

The mechanophysiology of tissues in the posterior eye have been implicated for diseases such as myopia and glaucoma. For example, the eye-globe shape, and consequently optical axial length, can be affected by scleral stiffness. In glaucoma, an elevated intraocular pressure is the primary risk factor for glaucoma, which is the 2nd most prevalent known cause of blindness. Recent work has shown that biomechanical properties of the optic nerve are critical for the onset and progression of glaucoma because weak tissues cause large displacements in the optic nerve, causing tissue damage. In this work, we utilize air-pulse optical coherence elastography (OCE) to quantify the spatial distribution of biomechanical properties of the optic nerve, its surrounding tissues, and the posterior sclera. Air-pulse measurements were made in a grid on in situ porcine eyes in the whole eye-globe configuration as various IOPs. The OCE-measured displacement process was linked to tissue stiffness by a simple kinematic equation. The results show that the optic nerve and peripapillary sclera are much stiffer than the surrounding sclera, and the stiffness of the optic nerve and peripapillary sclera increased as a function of IOP. However, the stiffness of the surrounding sclera did not dramatically increase. Our results show that understanding the dynamics of the biomechanical properties of the eye are critical to understand the aforementioned diseases and may provide additional information for assessing visual health and integrity.

Determining degree of optic nerve edema from color fundus photography

NASA Astrophysics Data System (ADS)

Agne, Jason; Wang, Jui-Kai; Kardon, Randy H.; Garvin, Mona K.

2015-03-01

Swelling of the optic nerve head (ONH) is subjectively assessed by clinicians using the Frisén scale. It is believed that a direct measurement of the ONH volume would serve as a better representation of the swelling. However, a direct measurement requires optic nerve imaging with spectral domain optical coherence tomography (SD-OCT) and 3D segmentation of the resulting images, which is not always available during clinical evaluation. Furthermore, telemedical imaging of the eye at remote locations is more feasible with non-mydriatic fundus cameras which are less costly than OCT imagers. Therefore, there is a critical need to develop a more quantitative analysis of optic nerve swelling on a continuous scale, similar to SD-OCT. Here, we select features from more commonly available 2D fundus images and use them to predict ONH volume. Twenty-six features were extracted from each of 48 color fundus images. The features include attributes of the blood vessels, optic nerve head, and peripapillary retina areas. These features were used in a regression analysis to predict ONH volume, as computed by a segmentation of the SD-OCT image. The results of the regression analysis yielded a mean square error of 2.43 mm3 and a correlation coefficient between computed and predicted volumes of R = 0:771, which suggests that ONH volume may be predicted from fundus features alone.

3D papillary image capturing by the stereo fundus camera system for clinical diagnosis on retina and optic nerve

NASA Astrophysics Data System (ADS)

Motta, Danilo A.; Serillo, André; de Matos, Luciana; Yasuoka, Fatima M. M.; Bagnato, Vanderlei S.; Carvalho, Luis A. V.

2014-03-01

Glaucoma is the second main cause of the blindness in the world and there is a tendency to increase this number due to the lifetime expectation raise of the population. Glaucoma is related to the eye conditions, which leads the damage to the optic nerve. This nerve carries visual information from eye to brain, then, if it has damage, it compromises the visual quality of the patient. In the majority cases the damage of the optic nerve is irreversible and it happens due to increase of intraocular pressure. One of main challenge for the diagnosis is to find out this disease, because any symptoms are not present in the initial stage. When is detected, it is already in the advanced stage. Currently the evaluation of the optic disc is made by sophisticated fundus camera, which is inaccessible for the majority of Brazilian population. The purpose of this project is to develop a specific fundus camera without fluorescein angiography and red-free system to accomplish 3D image of optic disc region. The innovation is the new simplified design of a stereo-optical system, in order to make capable the 3D image capture and in the same time quantitative measurements of excavation and topography of optic nerve; something the traditional fundus cameras do not do. The dedicated hardware and software is developed for this ophthalmic instrument, in order to permit quick capture and print of high resolution 3D image and videos of optic disc region (20° field-of-view) in the mydriatic and nonmydriatic mode.

Characterizing Intraorbital Optic Nerve Changes on Diffusion Tensor Imaging in Thyroid Eye Disease Before Dysthyroid Optic Neuropathy.

PubMed

Lee, Hwa; Lee, Young Hen; Suh, Sang-Il; Jeong, Eun-Kee; Baek, Sehyun; Seo, Hyung Suk

The aim of this study was to determine whether the optic nerve is affected by thyroid eye disease (TED) before the development of dysthyroid optic neuropathy with diffusion-tensor imaging (DTI). Twenty TED patients and 20 controls were included. The mean, axial, and radial diffusivities and fractional anisotropy (FA) value were measured at the optic nerves in DTI. Extraocular muscle diameters were measured on computed tomography. The diffusivities and FA of the optic nerves were compared between TED and controls and between active and inactive stages of TED. The correlations between these DTI parameters and the clinical features were determined. The mean, axial, and radial diffusivities were lower in TED compared with the controls (P < 0.05). In contrast, FA was higher in TED (P = 0.001). Radial diffusivity was lower in the active stage of TED than the inactive stage (P = 0.035). The FA was higher in the TED group than in the control group (P = 0.021) and was positively correlated with clinical activity score (r = 0.364, P = 0.021), modified NOSPECS score (r = 0.469, P = 0.002), and extraocular muscle thickness (r = 0.325, P = 0.041) in the TED group. Radial diffusivity was negatively correlated with modified NOSPECS score (r = -0.384, P = 0.014), and axial diffusivity was positively correlated with exophthalmos degree (r = 0.363, P = 0.025). The diffusivities and FA reflected changes in the optic nerve before dysthyroid optic neuropathy in TED. The FA, in particular, reflected TED activity and severity.

Unilateral Multiple Facial Nerve Branch Reconstruction Using “End-to-side Loop Graft” Supercharged by Hypoglossal Nerve

PubMed Central

Sasaki, Ryo; Takeuchi, Yuichi; Watanabe, Yorikatsu; Niimi, Yosuke; Sakurai, Hiroyuki; Miyata, Mariko; Yamato, Masayuki

2014-01-01

Background: Extensive facial nerve defects between the facial nerve trunk and its branches can be clinically reconstructed by incorporating double innervation into an end-to-side loop graft technique. This study developed a new animal model to evaluate the technique’s ability to promote nerve regeneration. Methods: Rats were divided into the intact, nonsupercharge, and supercharge groups. Artificially created facial nerve defects were reconstructed with a nerve graft, which was end-to-end sutured from proximal facial nerve stump to the mandibular branch (nonsupercharge group), or with the graft of which other end was end-to-side sutured to the hypoglossal nerve (supercharge group). And they were evaluated after 30 weeks. Results: Axonal diameter was significantly larger in the supercharge group than in the nonsupercharge group for the buccal (3.78 ± 1.68 vs 3.16 ± 1.22; P < 0.0001) and marginal mandibular branches (3.97 ± 2.31 vs 3.46 ± 1.57; P < 0.0001), but the diameter was significantly larger in the intact group for all branches except the temporal branch. In the supercharge group, compound muscle action potential amplitude was significantly higher than in the nonsupercharge group (4.18 ± 1.49 mV vs 1.87 ± 0.37 mV; P < 0.0001) and similar to that in the intact group (4.11 ± 0.68 mV). Retrograde labeling showed that the mimetic muscles were double-innervated by facial and hypoglossal nerve nuclei in the supercharge group. Conclusions: Multiple facial nerve branch reconstruction with an end-to-side loop graft was able to achieve axonal distribution. Additionally, axonal supercharge from the hypoglossal nerve significantly improved outcomes. PMID:25426357

Management of unilateral recurrent laryngeal nerve injury after thyroid surgery: A review.

PubMed

Lynch, Jeremy; Parameswaran, Rajeev

2017-07-01

Recurrent laryngeal nerve (RLN) damage because of thyroid and parathyroid surgery has been recognized for over a century. Injury rates have been slowly decreasing in this period while effective treatment strategies have been increasing. Recent literature was evaluated on the topics of anatomy, pathophysiology, avoidance, and conservative and surgical treatment of RLN injury. Data for this literature review were identified by PubMed and references from relevant articles using the search terms "thyroid," "laryngeal nerve," and "injury." Only articles published in English between 1990 and 2015 were included. Advances in technique and equipment have made injury less likely. The evidence and role for neuromonitoring is discussed. Treatment strategies may include speech therapy, vocal cord augmentation using injection, laryngeal framework surgery techniques (including laryngoplasty and arytenoid adduction), and reinnervation. Injury rates in specialist centers are very low. Good to excellent results may be obtained in most cases. © 2017 Wiley Periodicals, Inc.

[Evaluation of central lymph node dissection for papillary thyroid carcinoma in cN0 T1/T2].

PubMed

Zhao, S Y; Ma, Y H; Yin, Z; Zhan, X X; Cheng, R C; Qian, J

2018-02-07

Objective: To evaluate the application of the central lymph node dissection (CLND) for papillary thyroid carcinoma (PTC) in cN0 T1/T2. Methods: Retrospective analysis of 532 cases with PTC in cN0 T1/T2 who underwent CLND between October 2014 and September 2016 in the Department of Thyroid Surgery, the First Affiliated Hospital of the Kunming Medical University. The incidence of central lymph node (CLN) metastasis and risk factors were analyzed. Results: CLN metastasis rates: 41.2% (42/102) in males vs 34.9% (150/430) in females, P =0.252; 33.9% (116/342) in single focal carcinoma vs 40.4% (74/183) in multifocal carcinoma, P =0.157; 44.0% (125/284) in patients with 45 years old or less vs 27.0% (67/248) in patients more than 45 years old, P =0.000; 30.3% (113/373) in microcarcinoma vs 50.9% (81/159) in non-microcarcinoma, P =0.000.In unilateral lesions, ipsilateral CLN metastasis was correlated with the tumor diameter ( P =0.012), but not with the number of lesions ( P =0.653). also contralateral CLN metastasis was correlated with the tumor diameter ( P =0.000), but not with the number of lesions ( P =0.815). For the left or right unilateral single focal lesion, the tumor diameter was not correlated with the metastasis of the posterior to right recurrent laryngeal nerve central lymph nodes (LN-prRLN-CLN) ( P =0.652, P =0.088). But in bilateral multifocal carcinoma the tumor diameter was correlated with metastasis of LN-prRLN-CLN ( P =0.039). Conclusions: Prophylactic CLND is reasonable for PTC in cN0 T1/T2. A bilateral CLND should be conducted for patients with bilateral multi-focus cancer and unilateral or bilateral non-microcarcinoma, especially in patients more than 45 years old. For unilateral single focal microcarcinoma on the right, the content of CLND should be from laryngeal nerve on right center to posterior branche; for unilateral single focal microcarcinoma on the left side, the left CLND should be conducted. An ipsilateral CLND can be considered in patients with unilateral multifocal microcarcinoma, and generally a routine dissection of the LN-prRLN-CLN is not required, however for bilateral non-microcarcinoma and the the non-microcarcinoma on the right side, the LN-prRLN-CLN dissection should be conducted.

Radiation treatment inhibits monocyte entry into the optic nerve head and prevents neuronal damage in a mouse model of glaucoma.

PubMed

Howell, Gareth R; Soto, Ileana; Zhu, Xianjun; Ryan, Margaret; Macalinao, Danilo G; Sousa, Gregory L; Caddle, Lura B; MacNicoll, Katharine H; Barbay, Jessica M; Porciatti, Vittorio; Anderson, Michael G; Smith, Richard S; Clark, Abbot F; Libby, Richard T; John, Simon W M

2012-04-01

Glaucoma is a common ocular disorder that is a leading cause of blindness worldwide. It is characterized by the dysfunction and loss of retinal ganglion cells (RGCs). Although many studies have implicated various molecules in glaucoma, no mechanism has been shown to be responsible for the earliest detectable damage to RGCs and their axons in the optic nerve. Here, we show that the leukocyte transendothelial migration pathway is activated in the optic nerve head at the earliest stages of disease in an inherited mouse model of glaucoma. This resulted in proinflammatory monocytes entering the optic nerve prior to detectable neuronal damage. A 1-time x-ray treatment prevented monocyte entry and subsequent glaucomatous damage. A single x-ray treatment of an individual eye in young mice provided that eye with long-term protection from glaucoma but had no effect on the contralateral eye. Localized radiation treatment prevented detectable neuronal damage and dysfunction in treated eyes, despite the continued presence of other glaucomatous stresses and signaling pathways. Injection of endothelin-2, a damaging mediator produced by the monocytes, into irradiated eyes, combined with the other glaucomatous stresses, restored neural damage with a topography characteristic of glaucoma. Together, these data support a model of glaucomatous damage involving monocyte entry into the optic nerve.

Microgravity-Driven Optic Nerve/Sheath Biomechanics Simulations

NASA Technical Reports Server (NTRS)

Ethier, C. R.; Feola, A.; Myers, J. G.; Nelson, E.; Raykin, J.; Samuels, B.

2016-01-01

Visual Impairment and Intracranial Pressure (VIIP) syndrome is a concern for long-duration space flight. Current thinking suggests that the ocular changes observed in VIIP syndrome are related to cephalad fluid shifts resulting in altered fluid pressures [1]. In particular, we hypothesize that increased intracranial pressure (ICP) drives connective tissue remodeling of the posterior eye and optic nerve sheath (ONS). We describe here finite element (FE) modeling designed to understand how altered pressures, particularly altered ICP, affect the tissues of the posterior eye and optic nerve sheath (ONS) in VIIP. METHODS: Additional description of the modeling methodology is provided in the companion IWS abstract by Feola et al. In brief, a geometric model of the posterior eye and optic nerve, including the ONS, was created and the effects of fluid pressures on tissue deformations were simulated. We considered three ICP scenarios: an elevated ICP assumed to occur in chronic microgravity, and ICP in the upright and supine positions on earth. Within each scenario we used Latin hypercube sampling (LHS) to consider a range of ICPs, ONH tissue mechanical properties, intraocular pressures (IOPs) and mean arterial pressures (MAPs). The outcome measures were biomechanical strains in the lamina cribrosa, optic nerve and retina; here we focus on peak values of these strains, since elevated strain alters cell phenotype and induce tissue remodeling. In 3D, the strain field can be decomposed into three orthogonal components, denoted as first, second and third principal strains. RESULTS AND CONCLUSIONS: For baseline material properties, increasing ICP from 0 to 20 mmHg significantly changed strains within the posterior eye and ONS (Fig. 1), indicating that elevated ICP affects ocular tissue biomechanics. Notably, strains in the lamina cribrosa and retina became less extreme as ICP increased; however, within the optic nerve, the occurrence of such extreme strains greatly increased as ICP was elevated (Fig. 2). In particular, c. 48 of simulations in the elevated ICP condition showed peak strains in the optic nerve that exceeded the strains expected on earth. Such extreme strains are likely important, since they represent a larger signal for mechano-responsive resident cells [2]. The models predicted little to no anterior motion of the prelaminar neural tissue (optic nerve swelling, or papilledema, secondary to axoplasmic stasis), typically seen with elevated ICP. Specialized FE models to capture axoplasmic stasis would be required to study papilledema. These results suggest that the most notable effect of elevated ICP may occur via direct optic nerve loading, rather than through connective tissue deformation. These FE models can inform the design of future studies designed to bridge the gap between biomechanics and pathophysiological function in VIIP.

Blood flow changes after unilateral carotid artery ligation monitored by optical coherence tomography

NASA Astrophysics Data System (ADS)

Ma, Yushu; Liang, Chengbo; Suo, Yanyan; Zhao, Yuqian; Wang, Yi; Xu, Tao; Wang, Ruikang; Ma, Zhenhe

2016-03-01

Unilateral carotid artery ligation which could induce adaptive improvement is a classic model that has been widely used to study pathology of ischemic disease. In those studies, blood flow is an important parameter to characterize the ischemia. Optical coherence tomography (OCT) is a powerful imaging modality which can provide depth resolved images in biological tissue with high spatial and temporal resolution. SPF rats was anesthetized with isoflurane and divided into two groups. In first group, bilateral carotid artery was surgically exposed, and then left carotid artery was ligated. Blood flow changes of the contralateral carotid artery was monitored using high speed spectral domain optical coherence tomography, including the absolute flow velocity and the flow volume. In the other group, skull window was opened at the ipsilateral cerebral cortex of ligation and blood supply of small artery was measured before and after the ligation. The measured results demonstrate the blood supply compensation process after unilateral carotid artery ligation. With the superiority of high resolution, OCT is an effective technology in monitoring results of carotid artery after ligation.

Retinitis pigmentosa inversa with unilateral high myopia with fellow eye optic disc pitting.

PubMed

Sheth, Saumil; Rush, Ryan; Narayanan, Raja

2011-01-01

To report a possible rare association of bilateral retinitis pigmentosa inversa (RPI) with unilateral high myopia with fellow eye optic disc pitting. A 55-year-old man with a history of reduced vision in the right eye since childhood presented with gradually decreasing vision in the left eye. On examination, a -23.00 diopter refractive error and diffuse chorioretinal atrophy consistent with pathologic myopia was found in the right eye. An optic disc pit with posterior pole pigmentary alterations thought to be consequent to a previous neurosensory detachment was found in the left eye. Though the retinal arteriolar attenuation seen in both eyes with an inconsistent history of night blindness since childhood pointed towards the possibility of a concurrently existing rod or rod-cone dystrophy, the posterior pole pigmentary alterations characteristic of RPI were clearly masked by the above pathologies. Optical coherence tomography demonstrated prominent foveal atrophy and an optic disc pit in the left eye. Electroretinography (ERG) demonstrated moderately attenuated amplitudes with prolonged implicit times of rod and cone responses bilaterally. The patient was diagnosed with bilateral RPI and anisometropic amblyopia in the right eye. This report documents a unique constellation of findings which include bilateral RPI and unilateral high myopia with an optic disc pit in the fellow eye. An ERG confirmation of a dystrophic etiology should be sought in suspicious cases, especially when findings are masked by the concurrent presence of other pathologies.

Facial reanimation with masseteric nerve: babysitter or permanent procedure? Preliminary results.

PubMed

Faria, Jose Carlos Marques; Scopel, Gean Paulo; Ferreira, Marcus Castro

2010-01-01

The authors are presenting a series of 10 cases of complete unilateral facial paralysis submitted to (I) end-to-end microsurgical coaptation of the masseteric branch of the trigeminal nerve and distal branches of the paralyzed facial nerve, and (II) cross-face sural nerve graft. The ages of the patients ranged from 5 to 63 years (mean: 44.1 years), and 8 (80%) of the patients were females. The duration of paralysis was no longer than 18 months (mean: 9.7 months). Follow-up varied from 6 to 18 months (mean: 12.6 months). Initial voluntary facial movements were observed between 3 and 6 months postoperatively (mean: 4.3 months). All patients were able to produce the appearance of a smile when asked to clench their teeth. Comparing the definition of the nasolabial fold and the degree of movement of the modiolus on both sides of the face, the voluntary smile was considered symmetrical in 8 cases. Recovery of the capacity to blink spontaneously was not observed. However, 8 patients were able to reduce or suspend the application of artificial tears. The authors suggest consideration of masseteric-facial nerve coaptation, whether temporary (baby-sitter) or permanent, as the principal alternative for reconstruction of facial paralysis due to irreversible nerve lesion with less than 18 months of duration.

Recurrent laryngeal nerve reinnervation for management of aspiration in a subset of children.

PubMed

Zur, Karen B; Carroll, Linda M

2018-01-01

Pediatric aspiration is a multifactorial process that is often complex to manage. Recurrent laryngeal nerve (RLN) injury can cause glottic insufficiency and aspiration. We describe three cases of unilateral vocal fold paralysis resulting in aspiration and the successful use of the RLN reinnervation for its treatment. The theory for utilizing the reinnervation procedure is that when glottic closure improves and a less breathy vocalization occurs, then the larynx is better equipped to protect the lower airway and avoid aspiration. Our cases demonstrate stronger voice and improved swallow function, with normalization of modified barium swallow evaluation, at approximately 6-months post reinnervation. Copyright © 2017. Published by Elsevier B.V.

Macular and retinal nerve fiber thickness in recovered and persistent amblyopia.

PubMed

Yassin, Sanaa A; Al-Tamimi, Elham R; Al-Hassan, Sultan

2015-12-01

The aim of this study was to investigate the presence of increased macular or retinal nerve fiber layer thickness (RNFLT) in amblyopic eyes, find if the increased macular or RNFLT is related to the lack of response in amblyopic eyes, and to explore whether the increased central macular thickness (CMT) in amblyopic eyes is purely related to the hyperopia. This is a prospective descriptive study. CMT and peripapillary RNFLT were measured by spectral-domain optical coherence tomography to evaluate 60 patients with unilateral-treated amblyopia (median age 11.00 year). Patients were divided into two groups: 33 patients in recovered amblyopia group and 27 patients in persistent amblyopia group. The mean CMT in the recovered group was 247.31 (±23.4) versus 246.8 (±32.7) µm (p = 0.95) for the persistent group. The mean peripapillary RNFLT was 99.13 (±12.1) versus 99.9 (±14.9) µm (p = 0.85) for the persistent group. In anisometropic amblyopia, there was no significant difference in CMT and RNFLT in either group. Also there was no relation between the type of refractive error and CMT or RNFLT. There was no significant difference in CMT and RNFLT in amblyopic eyes for both the recovered amblyopia group and the persistent amblyopia group to explain the lack of response in persistent amblyopic eyes. Additionally there was no relation between the type of refractive error and CMT or peripapillary RNFLT.

Cranial nerve threshold for thermal injury induced by MRI-guided high-intensity focused ultrasound (MRgHIFU): preliminary results on an optic nerve model.

PubMed

Harnof, Sagi; Zibly, Zion; Cohen, Zvi; Shaw, Andrew; Schlaff, Cody; Kassel, Neal F

2013-04-01

Future clinical applications of magnetic resonance imaging-guided high-intensity focused ultrasound (MRgHIFU) are moving toward the management of different intracranial pathologies. We sought to validate the production, safety, and efficacy of thermal injury to cranial nerves generated by MRgHIFU. In this study, five female domestic pigs underwent a standard bifrontal craniectomy under general anesthesia. Treatment was then given using an MRgHIFU system to induce hyperthermic ablative sonication (6 to 10 s; 50 to 2000 J.) Histological analyses were done to confirm nerve damage; temperature measured on the optic nerve was approximately 53.4°C (range: 39°C to 70°C.) Histology demonstrated a clear definition between a necrotic, transitional zone, and normal tissue. MRgHIFU induces targeted thermal injury to nervous tissue within a specific threshold of 50°C to 60°C with the tissue near the sonication center yielding the greatest effect; adjacent tissue showed minimal changes. Additional studies utilizing this technology are required to further establish accurate threshold parameters for optic nerve thermo-ablation.

The renal nerves in chronic heart failure: efferent and afferent mechanisms

PubMed Central

Schiller, Alicia M.; Pellegrino, Peter R.; Zucker, Irving H.

2015-01-01

The function of the renal nerves has been an area of scientific and medical interest for many years. The recent advent of a minimally invasive catheter-based method of renal denervation has renewed excitement in understanding the afferent and efferent actions of the renal nerves in multiple diseases. While hypertension has been the focus of much this work, less attention has been given to the role of the renal nerves in the development of chronic heart failure (CHF). Recent studies from our laboratory and those of others implicate an essential role for the renal nerves in the development and progression of CHF. Using a rabbit tachycardia model of CHF and surgical unilateral renal denervation, we provide evidence for both renal efferent and afferent mechanisms in the pathogenesis of CHF. Renal denervation prevented the decrease in renal blood flow observed in CHF while also preventing increases in Angiotensin-II receptor protein in the microvasculature of the renal cortex. Renal denervation in CHF also reduced physiological markers of autonomic dysfunction including an improvement in arterial baroreflex function, heart rate variability, and decreased resting cardiac sympathetic tone. Taken together, the renal sympathetic nerves are necessary in the pathogenesis of CHF via both efferent and afferent mechanisms. Additional investigation is warranted to fully understand the role of these nerves and their role as a therapeutic target in CHF. PMID:26300788

Moebius syndrome with Dandy-Walker variant and agenesis of corpus callosum

PubMed Central

John, Jomol Sara; Vanitha, R.

2013-01-01

Moebius syndrome is a rare congenital neurological disorder. The most frequent mode of presentation is facial diplegia with bilateral lateral rectus palsy, but there are variations. Here, we report a rare case of Moebius syndrome in a 15-month-old child with unilateral facial palsy, bilateral abducens nerve palsy with Dandy Walker variant, and complete agenesis of corpus callosum. PMID:24470815

Head sway response to optic flow: effect of age is more important than the presence of unilateral vestibular hypofunction

PubMed Central

Sparto, Patrick J.; Furman, Joseph M.; Redfern, Mark S.

2014-01-01

Background The purpose of this study was to examine how older adults with vestibular impairment use sensory feedback for postural control. Methods Nine older adult subjects with unilateral vestibular hypofunction (UVH, mean age 69 y) and 14 older (mean age 70 y) and 8 young adult controls (CON, mean age 28 y) viewed full-field optic flow scenes while standing on a fixed or sway-referenced support surface. The subjects with UVH had 100% caloric asymmetry. Optic flow consisted of sinusoidal anterior-posterior movement of the visual surround at three frequencies and three amplitudes of stimulation. The anterior-posterior head sway was measured. The number of head sway responses that were coupled to the optic flow and magnitude of head sway during optic flow relative to during quiet stance on fixed floor was quantified. Results The number of trials in which the head sway response was significantly coupled to the optic flow was significantly greater in the Older UVH and Older CON subjects compared with the Young CON subjects. Furthermore, the magnitude of head sway was two to three times greater in Older UVH and CON compared with Young CON subjects. There was no difference in coupling or magnitude of head sway between Older UVH and Older CON subjects. The amplitude of sway was also dependent on the amount of surface support, stimulus frequency, and stimulus amplitude. Conclusions Older adults with unilateral vestibular hypofunction who are able to effectively compensate show no difference in postural responses elicited by optic flow compared with age-matched controls. PMID:17312341

Hemifacial Spasm and Neurovascular Compression

PubMed Central

Lu, Alex Y.; Yeung, Jacky T.; Gerrard, Jason L.; Michaelides, Elias M.; Sekula, Raymond F.; Bulsara, Ketan R.

2014-01-01

Hemifacial spasm (HFS) is characterized by involuntary unilateral contractions of the muscles innervated by the ipsilateral facial nerve, usually starting around the eyes before progressing inferiorly to the cheek, mouth, and neck. Its prevalence is 9.8 per 100,000 persons with an average age of onset of 44 years. The accepted pathophysiology of HFS suggests that it is a disease process of the nerve root entry zone of the facial nerve. HFS can be divided into two types: primary and secondary. Primary HFS is triggered by vascular compression whereas secondary HFS comprises all other causes of facial nerve damage. Clinical examination and imaging modalities such as electromyography (EMG) and magnetic resonance imaging (MRI) are useful to differentiate HFS from other facial movement disorders and for intraoperative planning. The standard medical management for HFS is botulinum neurotoxin (BoNT) injections, which provides low-risk but limited symptomatic relief. The only curative treatment for HFS is microvascular decompression (MVD), a surgical intervention that provides lasting symptomatic relief by reducing compression of the facial nerve root. With a low rate of complications such as hearing loss, MVD remains the treatment of choice for HFS patients as intraoperative technique and monitoring continue to improve. PMID:25405219

Bell palsy in lyme disease-endemic regions of canada: a cautionary case of occult bilateral peripheral facial nerve palsy due to Lyme disease.

PubMed

Ho, Karen; Melanson, Michel; Desai, Jamsheed A

2012-09-01

Lyme disease caused by the spirochete Borrelia burgdorferi is a multisystem disorder characterized by three clinical stages: dermatologic, neurologic, and rheumatologic. The number of known Lyme disease-endemic areas in Canada is increasing as the range of the vector Ixodes scapularis expands into the eastern and central provinces. Southern Ontario, Nova Scotia, southern Manitoba, New Brunswick, and southern Quebec are now considered Lyme disease-endemic regions in Canada. The use of field surveillance to map risk and endemic regions suggests that these geographic areas are growing, in part due to the effects of climate warming. Peripheral facial nerve palsy is the most common neurologic abnormality in the second stage of Lyme borreliosis, with up to 25% of Bell palsy (idiopathic peripheral facial nerve palsy) occurring due to Lyme disease. Here we present a case of occult bilateral facial nerve palsy due to Lyme disease initially diagnosed as Bell palsy. In Lyme disease-endemic regions of Canada, patients presenting with unilateral or bilateral peripheral facial nerve palsy should be evaluated for Lyme disease with serologic testing to avoid misdiagnosis. Serologic testing should not delay initiation of appropriate treatment for presumed Bell palsy.

Effect of sensory denervation on the structure and physiologic responsiveness of rabbit lacrimal gland.

PubMed

Meneray, M A; Bennett, D J; Nguyen, D H; Beuerman, R W

1998-01-01

This work was conducted to determine the effects of unilateral trigeminal ganglion ablation on lacrimal gland structure and secretory activity. Adult male New Zealand rabbits underwent unilateral thermocoagulation of the ophthalmic division of the trigeminal ganglion. Sensory denervation was affirmed by anatomic inspection of the lesion and transmission electron microscopy (TEM) of the lacrimal gland innervation. Eight to 10 days after the procedure, the intraorbital lacrimal glands were removed from both sides. To compare the physiologic competence of the intact and denervated glands, freshly isolated gland fragments from the paired intact and denervated glands were stimulated with carbachol (100 microM), isoproterenol (10 microM), phorbol-12,13-dibutyrate (PDBu, 10 microM), forskolin (40 microM), or vehicle. Total secreted protein was measured at 30 or 60 min after the establishment of baseline values. Intact and denervated glands also were examined by light and TEM, and the morphologic appearance of the acinar structures as well as the appearance of nerves innervating the gland after denervation were assessed. Similar experiments were conducted with animals that underwent unilateral superior cervical ganglionectomy. Tissues from sensory denervated glands released significantly more protein than did tissues from innervated glands in response to in vitro stimulation by carbachol or isoproterenol but not in response to PDBu or forskolin. Microscopy showed that the acinar cells that had undergone sensory denervation showed a massive accumulation of secretory granules. The secretory granules filled the entire cytoplasmic space and displaced the ellipsoidal nuclei to the extreme periphery. Examination of segments of nerves revealed numerous unmyelinated axons, a few small-diameter myelinated axons, and a large amount of nerve degeneration after sensory denervation. In contrast to the effects of sensory denervation, sympathetic denervation did not alter either the acinar appearance or secretory responsiveness of the gland. Loss of the considerable sensory innervation from the trigeminal ganglion has pronounced effects on the pharmacologic responsiveness and the structure of the lacrimal gland. The effects of sensory innervation on the gland may be mediated through two possible pathways: direct input to the gland or control of the preganglionic parasympathetic pathway.

Postoperative vocal fold palsy in patients undergoing thyroid surgery with continuous or intermittent nerve monitoring.

PubMed

Schneider, R; Sekulla, C; Machens, A; Lorenz, K; Nguyen Thanh, P; Dralle, H

2015-10-01

Continuous monitoring of electromyographic (EMG) amplitudes of the vocal muscles detects impending injury of the recurrent laryngeal nerve (RLN) during thyroid operations earlier than intermittent EMG monitoring. This may alert the surgeon to stop a manoeuvre causing stretching or pressure on the RLN, with better recovery of nerve function. Patients with intact preoperative RLN function who underwent thyroid surgery for benign disease between January 2011 and September 2014 under continuous intraoperative nerve monitoring (CIONM) or intermittent intraoperative nerve monitoring (IIONM) were included in this observational study conducted at a tertiary surgical centre. For CIONM, combined EMG events indicative of imminent nerve injury were defined as an EMG amplitude decrease of 50 per cent or more and a latency increase of 10 per cent relative to baseline values. The rates of early and permanent palsy for the two groups of patients were compared. There were 1526 patients, 788 of whom (1314 nerves at risk) underwent thyroid surgery using CIONM and 738 (965 nerves at risk) had IIONM. With the use of CIONM, 63 (82 per cent) of 77 combined events were reversible during the operation. No permanent vocal fold palsy occurred with CIONM, whereas four unilateral permanent vocal fold palsies (0·4 per cent) were diagnosed after IIONM (P = 0·019). Operation with CIONM resulted in fewer permanent vocal fold palsies compared with IIONM after thyroid surgery in patients with benign disease. © 2015 BJS Society Ltd Published by John Wiley & Sons Ltd.

Microstructural Changes in Compressed Nerve Roots Are Consistent With Clinical Symptoms and Symptom Duration in Patients With Lumbar Disc Herniation.

PubMed

Wu, Weifei; Liang, Jie; Ru, Neng; Zhou, Caisheng; Chen, Jianfeng; Wu, Yongde; Yang, Zong

2016-06-01

A prospective study. To investigate the association between microstructural nerve roots changes on diffusion tensor imaging (DTI) and clinical symptoms and their duration in patients with lumbar disc herniation. The ability to identify microstructural properties of the nervous system with DTI has been demonstrated in many studies. However, there are no data regarding the association between microstructural changes evaluated using DTI and symptoms assessed with the Oswestry Disability Index (ODI) and their duration. Forty consecutive patients with foraminal disc herniation affecting unilateral sacral 1 (S1) nerve roots were enrolled in this study. DTI with tractography was performed on the S1 nerve roots. Clinical symptoms were evaluated using an ODI questionnaire for each patient, and the duration of clinical symptoms was noted based on the earliest instance of leg pain and numbness. Mean fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were calculated from tractography images. The mean FA value of the compressed lumbar nerve roots was significantly lower than the FA of the contralateral nerve roots (P < 0.001). No notable difference in ADC was observed between compressed nerve roots and contralateral nerve roots (P = 0.517). In the compressed nerve roots, a significant negative association was observed between FA values and ODI and symptom duration. However, an obvious positive association was observed between ODI and ADC values and duration on the compressed side. Significant changes in diffusion parameters were found in the compressed sacral nerves in patients with lumbar disc herniation and leg pain, indicating that the microstructure of the nerve root has been damaged. 3.

Ocular Manifestations of Oblique Facial Clefts

PubMed Central

Ortube, Maria Carolina; Dipple, Katrina; Setoguchi, Yoshio; Kawamoto, Henry K.; Demer, Joseph L.

2014-01-01

Introduction In the Tessier classification, craniofacial clefts are numbered from 0 to 14 and extend along constant axes through the eyebrows, eyelids, maxilla, nostrils, and the lips. We studied a patient with bilateral cleft 10 associated with ocular abnormalities. Method Clinical report with orbital and cranial computed tomography. Results After pregnancy complicated by oligohydramnios, digoxin, and lisinopril exposure, a boy was born with facial and ocular dysmorphism. Examination at age 26 months showed bilateral epibulbar dermoids, covering half the corneal surface, and unilateral morning glory anomaly of the optic nerve. Ductions of the right eye were normal, but the left eye had severely impaired ductions in all directions, left hypotropia, and esotropia. Under anesthesia, the left eye could not be rotated freely in any direction. Bilateral Tessier cleft number 10 was implicated by the presence of colobomata of the middle third of the upper eyelids and eyebrows. As the cleft continued into the hairline, there was marked anterior scalp alopecia. Computed x-ray tomography showed a left middle cranial fossa arachnoid cyst and calcification of the reflected tendon of the superior oblique muscle, trochlea, and underlying sclera, with downward and lateral globe displacement. Discussion Tessier 10 clefts are very rare and usually associated with encephalocele. Bilateral 10 clefts have not been reported previously. In this case, there was coexisting unilateral morning glory anomaly and arachnoid cyst of the left middle cranial fossa but no encephalocele. Conclusions Bilateral Tessier facial cleft 10 may be associated with alopecia, morning glory anomaly, epibulbar dermoids, arachnoid cyst, and restrictive strabismus. PMID:20856062

Tolerance of cranial nerves of the cavernous sinus to radiosurgery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tishler, R.B.; Loeffler, J.S.; Alexander, E. III

1993-09-20

Stereotactic radiosurgery is becoming a more accepted treatment option for benign, deep seated intracranial lesions. However, little is known about the effects of large single fractions of radiation on cranial nerves. This study was undertaken to assess the effect of radiosurgery on the cranial nerves of the cavernous sinus. The authors examined the tolerance of cranial nerves (II-VI) following radiosurgery for 62 patients (42/62 with meningiomas) treated for lesions within or near the cavernous sinus. Twenty-nine patients were treated with a modified 6 MV linear accelerator (Joint Center for Radiation Therapy) and 33 were treated with the Gamma Knife (Universitymore » of Pittsburgh). Three-dimensional treatment plans were retrospectively reviewed and maximum doses were calculated for the cavernous sinus and the optic nerve and chiasm. Median follow-up was 19 months (range 3-49). New cranial neuropathies developed in 12 patients from 3-41 months following radiosurgery. Four of these complications involved injury to the optic system and 8 (3/8 transient) were the result of injury to the sensory or motor nerves of the cavernous sinus. There was no clear relationship between the maximum dose to the cavernous sinus and the development of complications for cranial nerves III-VI over the dose range used (1000-4000 cGy). For the optic apparatus, there was a significantly increased incidence of complications with dose. Four of 17 patients (24%) receiving greater than 800 cGy to any part of the optic apparatus developed visual complications compared with 0/35 who received less than 800 cGy (p = 0.009). Radiosurgery using tumor-controlling doses of up to 4000 cGy appears to be a relatively safe technique in treating lesions within or near the sensory and motor nerves (III-VI) of the cavernous sinus. The dose to the optic apparatus should be limited to under 800 cGy. 21 refs., 4 tabs.« less

Applications of Optical Coherence Tomography in Pediatric Clinical Neuroscience

PubMed Central

Avery, Robert A.; Rajjoub, Raneem D.; Trimboli-Heidler, Carmelina; Waldman, Amy T.

2015-01-01

For nearly two centuries, the ophthalmoscope has permitted examination of the retina and optic nerve—the only axons directly visualized by the physician. The retinal ganglion cells project their axons, which travel along the innermost retina to form the optic nerve, marking the beginning of the anterior visual pathway. Both the structure and function of the visual pathway are essential components of the neurologic examination as it can be involved in numerous acquired, congenital and genetic central nervous system conditions. The development of optical coherence tomography now permits the pediatric neuroscientist to visualize and quantify the optic nerve and retinal layers with unprecedented resolution. As optical coherence tomography becomes more accessible and integrated into research and clinical care, the pediatric neuroscientist may have the opportunity to utilize and/or interpret results from this device. This review describes the basic technical features of optical coherence tomography and highlights its potential clinical and research applications in pediatric clinical neuroscience including optic nerve swelling, optic neuritis, tumors of the visual pathway, vigabatrin toxicity, nystagmus, and neurodegenerative conditions. PMID:25803824

Optically-Induced Neuronal Activity Is Sufficient to Promote Functional Motor Axon Regeneration In Vivo.

PubMed

Ward, Patricia J; Jones, Laura N; Mulligan, Amanda; Goolsby, William; Wilhelm, Jennifer C; English, Arthur W

2016-01-01

Peripheral nerve injuries are common, and functional recovery is very poor. Beyond surgical repair of the nerve, there are currently no treatment options for these patients. In experimental models of nerve injury, interventions (such as exercise and electrical stimulation) that increase neuronal activity of the injured neurons effectively enhance axon regeneration. Here, we utilized optogenetics to determine whether increased activity alone is sufficient to promote motor axon regeneration. In thy-1-ChR2/YFP transgenic mice in which a subset of motoneurons express the light-sensitive cation channel, channelrhodopsin (ChR2), we activated axons in the sciatic nerve using blue light immediately prior to transection and surgical repair of the sciatic nerve. At four weeks post-injury, direct muscle EMG responses evoked with both optical and electrical stimuli as well as the ratio of these optical/electrical evoked EMG responses were significantly greater in mice that received optical treatment. Thus, significantly more ChR2+ axons successfully re-innervated the gastrocnemius muscle in mice that received optical treatment. Sections of the gastrocnemius muscles were reacted with antibodies to Synaptic Vesicle Protein 2 (SV2) to quantify the number of re-occupied motor endplates. The number of SV2+ endplates was greater in mice that received optical treatment. The number of retrogradely-labeled motoneurons following intramuscular injection of cholera toxin subunit B (conjugated to Alexa Fluor 555) was greater in mice that received optical treatment. Thus, the acute (1 hour), one-time optical treatment resulted in robust, long-lasting effects compared to untreated animals as well as untreated axons (ChR2-). We conclude that neuronal activation is sufficient to promote motor axon regeneration, and this regenerative effect is specific to the activated neurons.

Three-dimensional digital mapping of the optic nerve head cupping in glaucoma

NASA Astrophysics Data System (ADS)

Mitra, Sunanda; Ramirez, Manuel; Morales, Jose

1992-08-01

Visualization of the optic nerve head cupping is clinically achieved by stereoscopic viewing of a fundus image pair of the suspected eye. A novel algorithm for three-dimensional digital surface representation of the optic nerve head, using fusion of stereo depth map with a linearly stretched intensity image of a stereo fundus image pair, is presented. Prior to depth map acquisition, a number of preprocessing tasks including feature extraction, registration by cepstral analysis, and correction for intensity variations are performed. The depth map is obtained by using a coarse to fine strategy for obtaining disparities between corresponding areas. The required matching techniques to obtain the translational differences in every step, uses cepstral analysis and correlation-like scanning technique in the spatial domain for the finest details. The quantitative and precise representation of the optic nerve head surface topography following this algorithm is not computationally intensive and should provide more useful information than just qualitative stereoscopic viewing of the fundus as one of the diagnostic criteria for diagnosis of glaucoma.

Bilateral Traumatic Globe Luxation with Optic Nerve Transection

PubMed Central

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

2014-01-01

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

Transdermal optogenetic peripheral nerve stimulation

NASA Astrophysics Data System (ADS)

Maimon, Benjamin E.; Zorzos, Anthony N.; Bendell, Rhys; Harding, Alexander; Fahmi, Mina; Srinivasan, Shriya; Calvaresi, Peter; Herr, Hugh M.

2017-06-01

Objective: A fundamental limitation in both the scientific utility and clinical translation of peripheral nerve optogenetic technologies is the optical inaccessibility of the target nerve due to the significant scattering and absorption of light in biological tissues. To date, illuminating deep nerve targets has required implantable optical sources, including fiber-optic and LED-based systems, both of which have significant drawbacks. Approach: Here we report an alternative approach involving transdermal illumination. Utilizing an intramuscular injection of ultra-high concentration AAV6-hSyn-ChR2-EYFP in rats. Main results: We demonstrate transdermal stimulation of motor nerves at 4.4 mm and 1.9 mm depth with an incident laser power of 160 mW and 10 mW, respectively. Furthermore, we employ this technique to accurately control ankle position by modulating laser power or position on the skin surface. Significance: These results have the potential to enable future scientific optogenetic studies of pathologies implicated in the peripheral nervous system for awake, freely-moving animals, as well as a basis for future clinical studies.

The vestibulo-ocular reflex in fourth nerve palsy: deficits and adaptation.

PubMed

Wong, Agnes M F; Sharpe, James A; Tweed, Douglas

2002-08-01

The effects of fourth nerve palsy on the vestibulo-ocular reflex (VOR) had not been systematically investigated. We used the magnetic scleral search coil technique to study the VOR in patients with unilateral fourth nerve palsy during sinusoidal head rotations in yaw, pitch and roll at different frequencies. In darkness, VOR gains are reduced during incyclotorsion, depression and abduction of the paretic eye, as anticipated from paresis of the superior oblique muscle. VOR gains during excyclotorsion, elevation and adduction of the paretic eye are also reduced, whereas gains in the non-paretic eye remain normal, indicating a selective adjustment of innervation to the paretic eye. In light, torsional visually enhanced VOR (VVOR) gains in the paretic eye remain reduced; however, visual input increases vertical and horizontal VVOR gains to normal in the paretic eye, without a conjugate increase in VVOR gains in the non-paretic eye, providing further evidence of selective adaptation in the paretic eye. Motions of the eyes after fourth nerve palsy exemplify monocular adaptation of the VOR, in response to peripheral neuromuscular deficits.

Phrenic nerve stimulation for the treatment of central sleep apnea.

PubMed

Abraham, William T; Jagielski, Dariusz; Oldenburg, Olaf; Augostini, Ralph; Krueger, Steven; Kolodziej, Adam; Gutleben, Klaus-Jürgen; Khayat, Rami; Merliss, Andrew; Harsch, Manya R; Holcomb, Richard G; Javaheri, Shahrokh; Ponikowski, Piotr

2015-05-01

The aim of this study was to evaluate chronic, transvenous, unilateral phrenic nerve stimulation to treat central sleep apnea (CSA) in a prospective, multicenter, nonrandomized study. CSA occurs predominantly in patients with heart failure and increases the risk for morbidity and mortality. Established therapies for CSA are lacking, and those available are limited by poor patient adherence. Fifty-seven patients with CSA underwent baseline polysomnography followed by transvenous phrenic nerve stimulation system implantation and follow-up. Feasibility was assessed by implantation success rate and therapy delivery. Safety was evaluated by monitoring of device- and procedure-related adverse events. Efficacy was evaluated by changes in the apnea-hypopnea index at 3 months. Quality of life at 6 months was evaluated using a sleepiness questionnaire, patient global assessment, and, in patients with heart failure at baseline, the Minnesota Living With Heart Failure Questionnaire. The study met its primary end point, demonstrating a 55% reduction in apnea-hypopnea index from baseline to 3 months (49.5 ± 14.6 episodes/h vs. 22.4 ± 13.6 episodes/h of sleep; p < 0.0001; 95% confidence interval for change: -32.3 to -21.9). Central apnea index, oxygenation, and arousals significantly improved. Favorable effects on quality of life and sleepiness were noted. In patients with heart failure, the Minnesota Living With Heart Failure Questionnaire score significantly improved. Device- or procedure-related serious adverse events occurred in 26% of patients through 6 months post therapy initiation, predominantly due to lead repositioning early in the study. Therapy was well tolerated. Efficacy was maintained at 6 months. Transvenous, unilateral phrenic nerve stimulation appears safe and effective for treating CSA. These findings should be confirmed in a prospective, randomized, controlled trial. (Chronic Evaluation of Respicardia Therapy; NCT01124370). Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Mirror-image pain after nerve reconstruction in rats is related to enhanced density of epidermal peptidergic nerve fibers.

PubMed

Kambiz, S; Brakkee, E M; Duraku, L S; Hovius, S E R; Ruigrok, T J H; Walbeehm, E T

2015-05-01

Mirror-image pain is a phenomenon in which unprovoked pain is detected on the uninjured contralateral side after unilateral nerve injury. Although it has been implicated that enhanced production of nerve growth factor (NGF) in the contralateral dorsal root ganglion is important in the development of mirror-image pain, it is not known if this is related to enhanced expression of nociceptive fibers in the contralateral skin. Mechanical and thermal sensitivity in the contralateral hind paw was measured at four different time points (5, 10, 20 and 30weeks) after transection and immediate end-to-end reconstruction of the sciatic nerve in rats. These findings were compared to the density of epidermal (peptidergic and non-peptidergic) nerve fibers on the contralateral hind paw. Mechanical hypersensitivity of the contralateral hind paw was observed at 10weeks PO, a time point in which both subgroups of epidermal nerve fibers reached control values. Thermal hypersensitivity was observed with simultaneous increase in the density of epidermal peptidergic nerve fibers of the contralateral hind paw at 20weeks PO. Both thermal sensitivity and the density of epidermal nerve fibers returned to control values 30weeks PO. We conclude that changes in skin innervation and sensitivity are present on the uninjured corresponding side in a transient pain model. Therefore, the contralateral side cannot serve as control. Moreover, the current study confirms the involvement of the peripheral nervous system in the development of mirror-image pain. Copyright © 2015 Elsevier Inc. All rights reserved.

Torsional Eye Movements Evoked by Unilateral Labyrinthine Galvanic Polarizations in the Squirrel Monkey

NASA Technical Reports Server (NTRS)

Minor, Lloyd B.; Tomko, David L.; Paige, Gary D.

1995-01-01

Electrical stimulation of vestibular-nerve afferents innervating the semicircular canals has been used to identify the extraocular muscles receiving activation or inhibition by individual ampullary nerves. This technique was originally developed by Szentagothai (1950) and led to the description of three neuron reflex arcs that connect each semicircular canal through an interneuron traversing in the region of the medial longitudinal fasciculus to one ipsilateral and one contralateral eye muscle. Selective ampullary nerve stimulation was subsequently used by Cohen and colleagues (Cohen and Suzuki, 1963; Cohen et al., 1964; Suzuki et al., 1964; Cohen et al., 1966) to study movements of the eyes and activation of individual extraocular muscles in response to stimulation of combinations of ampullary nerves. This work led to a description of the now familiar relationships between activation of a semicircular canal ampullary nerves and the anticipated movement in each eye. Disconjugacy of eye movements induced by individual vertical canal stimulation and dependence of the pulling direction of vertical recti and oblique muscles on eye position were also defined in these experiments. Subsequent studies have defined the mechanisms by which externally applied galvanic currents result in a change in vestibular-nerve afferent discharge. The currents appear to act at the spike trigger site. Perilymphatic cathodal currents depolarize the trigger site and lead to excitation whereas anodal currents hyperpolarize and result in inhibition. Afferents innervating all five vestibular endorgans appear to be affected equally by the currents (Goldberg et al., 1984). Irregularly discharging afferents are about 5-10 times more sensitive than regularly discharging ones because of the steeper slope of the former's faster postspike recovery of excitability in encoder sensitivity (Smith and Goldberg, 1986). Response adaptation similar to that noted during acceleration steps is apparent for longer periods of current administration. This adaptation is manifested as a perstimulus return toward resting discharge and poststimulus after-response in the opposite direction (Goldberg et al., 1984; Minor and Goldberg, l991). Cathodal currents (with respect to the perilymphatic space of the vestibule) are excitatory whereas anodal currents are inhibitory. Horizontal eye movements evoked by unilateral galvanic polarizations administered through chronically implanted labyrinthine stimulating electrodes have been studied in alert squirrel monkeys (Minor and Goldberg, 1991). We sought to extend this analysis by recording three-dimensional eye movements during galvanic stimulation. As predicted based upon roughly equal stimulation of ampullary nerves innervating the vertical canals, a substantial torsional component to the nystagmus is noted. The trajectory of torsional slow phases and nystagmus profile after the polarization provide insight into the central mechanisms that influence these responses.

Evaluation of retinal nerve fiber layer thickness in the area of apparently normal hemifield in glaucomatous eyes with optical coherence tomography.

PubMed

Kee, Changwon; Cho, Changhwan

2003-06-01

The authors investigated the correlation between visual field defects detected by automated perimetry and the thickness of the retinal nerve fiber layer measured with optical coherence tomography, and examined whether there is a decrease in retinal nerve fiber layer thickness in the apparently normal hemifield of glaucomatous eyes. Forty-one patients with glaucoma and 41 normal control subjects were included in this study. Statistical correlations between the sum of the total deviation of 37 stimuli of each hemifield and the ratio of decrease in retinal nerve fiber layer thickness were evaluated. The statistical difference between the retinal nerve fiber layer thickness of the apparently normal hemifield in glaucomatous eyes and that of the corresponding hemifield in normal subjects was also evaluated. There was a statistically significant correlation in the sum of the total deviation and retinal nerve fiber layer thickness decrease ratio (superior hemifield, P = 0.001; inferior hemifield, P = 0.003). There was no significant decrease in retinal nerve fiber layer thickness in the area that corresponded to the normal visual field in the hemifield defect with respect to the horizontal meridian in glaucomatous eyes (superior side, P = 0.148; inferior side, P = 0.341). Optical coherence tomography was capable of demonstrating and measuring retinal nerve fiber layer abnormalities. No changes in the retinal nerve fiber layer thickness of the apparently normal hemifield were observed in glaucomatous eyes.

Optic Nerve Sheath Meningocele: A Case Report

PubMed Central

Halimi, E.; Wavreille, O.; Rosenberg, R.; Bouacha, I.; Lejeune, J.-P.; Defoort-Dhellemmes, S.

2013-01-01

Abstract Isolated optic nerve sheath meningocele is a rare affection defined as the cystic enlargement of the optic nerve sheath filled with cerebrospinal fluid. We report the case of a 39-year-old woman presenting with bilateral meningocele uncovered during a routine examination for headache complaints. A 5-year follow-up validated the lesion’s clinical and imaging stability. Magnetic resonance imaging (MRI) is an essential tool in the diagnosis of this pathology, alongside characteristic symptoms indicating that the meningocele might have progressively expanded into the orbit. In this case we present a therapeutic approach based on pathophysiological hypotheses and review of the literature. PMID:28163760

Is the term "fasciculus opticus cerebralis" more justifiable than the term "optic nerve"?

PubMed

Vojniković, Bojo; Bajek, Snjezana; Bajek, Goran; Strenja-Linić, Ines; Grubesić, Aron

2013-04-01

The terminology of the optic nerve had already been changed three times, since 1895 until 1955 when the term "nervus opticus" was introduced in the "Terminologia Anatomica". Following our study we claim that, from the aspect of phylogenetic evolution of binocular vision development as well as optical embryogenesis where opticus is evidently presented as a product of diencephalic structures, the addition of the term "nervus" to opticus is not adequate and justified. From the clinical aspect the term "nervus opticus" is also inadequate, both as a "nerve" that has no functional regenerative properties, unlike other cranial nerves, as well as from a pedagogical and didactical aspect of educating future physicians. We suggest that the term "Fasciculus Opticus Cerebralis" should be used as it much better explains the origin as well as its affiliation to the central nervous system.

ImagePAD, a Novel Counting Application for the Apple iPad®, Used to Quantify Axons in the Mouse Optic Nerve

PubMed Central

Templeton, Justin P.; Struebing, Felix L.; Lemmon, Andrew; Geisert, Eldon E.

2014-01-01

The present article introduces a new and easy to use counting application for the Apple iPad. The application “ImagePAD” takes advantage of the advanced user interface features offered by the Apple iOS® platform, simplifying the rather tedious task of quantifying features in anatomical studies. For example, the image under analysis can be easily panned and zoomed using iOS-supported multi-touch gestures without losing the spatial context of the counting task, which is extremely important for ensuring count accuracy. This application allows one to quantify up to 5 different types of objects in a single field and output the data in a tab-delimited format for subsequent analysis. We describe two examples of the use of the application: quantifying axons in the optic nerve of the C57BL/6J mouse and determining the percentage of cells labeled with NeuN or ChAT in the retinal ganglion cell layer. For the optic nerve, contiguous images at 60× magnification were taken and transferred onto an Apple iPad®. Axons were counted by tapping on the touch-sensitive screen using ImagePAD. Nine optic nerves were sampled and the number of axons in the nerves ranged from 38872 axons to 50196 axons with an average of 44846 axons per nerve (SD = 3980 axons). PMID:25281829

Mobile zinc increases rapidly in the retina after optic nerve injury and regulates ganglion cell survival and optic nerve regeneration

PubMed Central

Li, Yiqing; Andereggen, Lukas; Yuki, Kenya; Omura, Kumiko; Yin, Yuqin; Gilbert, Hui-Ya; Erdogan, Burcu; Asdourian, Maria S.; Shrock, Christine; de Lima, Silmara; Apfel, Ulf-Peter; Zhuo, Yehong; Hershfinkel, Michal; Lippard, Stephen J.; Benowitz, Larry

2017-01-01

Retinal ganglion cells (RGCs), the projection neurons of the eye, cannot regenerate their axons once the optic nerve has been injured and soon begin to die. Whereas RGC death and regenerative failure are widely viewed as being cell-autonomous or influenced by various types of glia, we report here that the dysregulation of mobile zinc (Zn2+) in retinal interneurons is a primary factor. Within an hour after the optic nerve is injured, Zn2+ increases several-fold in retinal amacrine cell processes and continues to rise over the first day, then transfers slowly to RGCs via vesicular release. Zn2+ accumulation in amacrine cell processes involves the Zn2+ transporter protein ZnT-3, and deletion of slc30a3, the gene encoding ZnT-3, promotes RGC survival and axon regeneration. Intravitreal injection of Zn2+ chelators enables many RGCs to survive for months after nerve injury and regenerate axons, and enhances the prosurvival and regenerative effects of deleting the gene for phosphatase and tensin homolog (pten). Importantly, the therapeutic window for Zn2+ chelation extends for several days after nerve injury. These results show that retinal Zn2+ dysregulation is a major factor limiting the survival and regenerative capacity of injured RGCs, and point to Zn2+ chelation as a strategy to promote long-term RGC protection and enhance axon regeneration. PMID:28049831

Mobile zinc increases rapidly in the retina after optic nerve injury and regulates ganglion cell survival and optic nerve regeneration.

PubMed

Li, Yiqing; Andereggen, Lukas; Yuki, Kenya; Omura, Kumiko; Yin, Yuqin; Gilbert, Hui-Ya; Erdogan, Burcu; Asdourian, Maria S; Shrock, Christine; de Lima, Silmara; Apfel, Ulf-Peter; Zhuo, Yehong; Hershfinkel, Michal; Lippard, Stephen J; Rosenberg, Paul A; Benowitz, Larry

2017-01-10

Retinal ganglion cells (RGCs), the projection neurons of the eye, cannot regenerate their axons once the optic nerve has been injured and soon begin to die. Whereas RGC death and regenerative failure are widely viewed as being cell-autonomous or influenced by various types of glia, we report here that the dysregulation of mobile zinc (Zn 2+ ) in retinal interneurons is a primary factor. Within an hour after the optic nerve is injured, Zn 2+ increases several-fold in retinal amacrine cell processes and continues to rise over the first day, then transfers slowly to RGCs via vesicular release. Zn 2+ accumulation in amacrine cell processes involves the Zn 2+ transporter protein ZnT-3, and deletion of slc30a3, the gene encoding ZnT-3, promotes RGC survival and axon regeneration. Intravitreal injection of Zn 2+ chelators enables many RGCs to survive for months after nerve injury and regenerate axons, and enhances the prosurvival and regenerative effects of deleting the gene for phosphatase and tensin homolog (pten). Importantly, the therapeutic window for Zn 2+ chelation extends for several days after nerve injury. These results show that retinal Zn 2+ dysregulation is a major factor limiting the survival and regenerative capacity of injured RGCs, and point to Zn 2+ chelation as a strategy to promote long-term RGC protection and enhance axon regeneration.

Measurement of wavefront aberrations in cortex and peripheral nerve using a two-photon excitation guidestar

NASA Astrophysics Data System (ADS)

Futia, Gregory L.; Fontaine, Arjun; McCullough, Connor; Ozbay, Baris N.; George, Nickolas M.; Caldwell, John; Restrepo, Diego; Weir, Richard; Gibson, Emily A.

2018-02-01

Neural-machine interfaces using optogenetics are of interest due to their minimal invasiveness and potential for parallel read in and read out of activity. One possible biological target for such an interface is the peripheral nerve, where axonlevel imaging or stimulation could greatly improve interfacing with artificial limbs or enable neuron/fascicle level neuromodulation in the vagus nerve. Two-photon imaging has been successful in imaging brain activity using genetically encoded calcium or voltage indicators, but in the peripheral nerve, this is severely limited by scattering and aberrations from myelin. We employ a Shack-Hartman wavefront sensor and two-photon excitation guidestar to quantify optical scattering and aberrations in peripheral nerves and cortex. The sciatic and vagus nerves, and cortex from a ChAT-Cre ChR-eYFP transgenic mouse were excised and imaged directly. In peripheral nerves, defocus was the strongest aberration followed by astigmatism and coma. Peripheral nerve had orders of magnitude higher aberration compared with cortex. These results point to the potential of adaptive optics for increasing the depth of two-photon access into peripheral nerves.

Near-infrared spectroscopy of the visual cortex in unilateral optic neuritis.

PubMed

Miki, Atsushi; Nakajima, Takashi; Takagi, Mineo; Usui, Tomoaki; Abe, Haruki; Liu, Chia-Shang J; Liu, Grant T

2005-02-01

To examine the occipital-lobe activation of patients with optic neuritis using near-infrared spectroscopy. Experimental study. NIRS was performed on five patients with acute unilateral optic neuritis during monocular visual stimulation. As controls, six normal subjects were also tested in the same manner. In the patients with optic neuritis, the changes in the hemoglobin concentrations (oxyhemoglobin, deoxyhemoglobin, and total hemoglobin) in the occipital lobe were found to be markedly reduced when the clinically affected eyes were stimulated compared with the fellow eyes. The response induced by the stimulation of the affected eye was decreased, even when the patient's visual acuity improved to 20/20 in the recovery phase. There was no difference in the concentration changes between the two eyes in the control subjects. NIRS may be useful in detecting visual dysfunction objectively and noninvasively in patients with visual disturbance, especially when used at the bedside.

Effect of the menstrual cycle on the optic nerve head in diabetes: analysis by confocal scanning laser ophthalmoscopy.

PubMed

Akar, Munire Erman; Yucel, Iclal; Erdem, Uzeyir; Taskin, Omur; Ozel, Alper; Akar, Yusuf

2005-04-01

The purpose of this study was to examine and compare menstrual-cycle-dependent topographic changes in the optic nerve head of normally menstruating women with different grades of type 2 diabetes mellitus. We studied the right eyes of 123 normally menstruating women (36 with severe nonproliferative diabetic retinopathy [NPDR], 42 with mild NPDR and 45 healthy subjects). All subjects underwent a complete ocular examination at baseline. At 4 hormonally distinct phases of the menstrual cycle (early follicular, late follicular, mid-luteal and late luteal), we analysed the topography of the optic nerve head, using a confocal scanning laser ophthalmoscope, and measured the serum levels of estradiol, progesterone and luteinizing hormone. We excluded from analysis the data for 8 patients with severe NPDR, 10 patients with mild NPDR and 15 control subjects who were lost to follow-up examinations during the menstrual cycle. The mean age and optic disc area did not differ significantly among the 3 groups. The duration of diabetes was significantly longer in the patients with severe NPDR than in those with mild NPDR (p < 0.05). The women with severe NPDR had a significantly increased neuroretinal rim area and a significantly decreased cup-shape measure, linear cup/disc ratio, cup/disc area ratio and cup area in the late luteal phase compared with the other phases of the menstrual cycle (p < 0.05). Those with mild NPDR or a normal retina had no significant topographic changes in the optic nerve head during the menstrual cycle. Severe NPDR is associated with significant topographic changes in the rim and cup of the optic nerve head during the menstrual cycle. This must be considered in the evaluation of women with both diabetes and glaucoma. The normal fluctuations in serum sex hormone levels during the menstrual cycle of diabetic women seem to affect the optic nerve head more when the disease is advanced.

Losartan Treatment Protects Retinal Ganglion Cells and Alters Scleral Remodeling in Experimental Glaucoma

PubMed Central

Pitha, Ian F.; Nguyen, Cathy; Steinhart, Matthew R.; Nguyen, Thao D.; Pease, Mary Ellen; Oglesby, Ericka N.; Berlinicke, Cynthia A.; Mitchell, Katherine L.; Kim, Jessica; Jefferys, Joan J.

2015-01-01

Purpose To determine if oral losartan treatment decreases the retinal ganglion cell (RGC) death caused by experimental intraocular pressure (IOP) elevation in mice. Methods We produced IOP increase in CD1 mice and performed unilateral optic nerve crush. Mice received oral losartan, spironolactone, enalapril, or no drug to test effects of inhibiting angiotensin receptors. IOP was monitored by Tonolab, and blood pressure was monitored by tail cuff device. RGC loss was measured in masked axon counts and RGC bodies by β-tubulin labeling. Scleral changes that could modulate RGC injury were measured including axial length, scleral thickness, and retinal layer thicknesses, pressure-strain behavior in inflation testing, and study of angiotensin receptors and pathways by reverse transcription polymerase chain reaction, Western blot, and immunohistochemistry. Results Losartan treatment prevented significant RGC loss (median loss = 2.5%, p = 0.13), while median loss with water, spironolactone, and enalapril treatments were 26%, 28% and 43%; p < 0.0001). The lower RGC loss with losartan was significantly less than the loss with spironolactone or enalapril (regression model p = 0.001; drug treatment group term p = 0.01). Both losartan and enalapril significantly lowered blood pressure (p< 0.001), but losartan was protective, while enalapril led to worse than water-treated RGC loss. RGC loss after crush injury was unaffected by losartan treatment (difference from control p = 0.9). Survival of RGC in cell culture was not prolonged by sartan treatment. Axonal transport blockade after 3 day IOP elevations was less in losartan-treated than in control glaucoma eyes (p = 0.007). Losartan inhibited effects of glaucoma, including reduction in extracellular signal-related kinase activity and modification of glaucoma-related changes in scleral thickness and creep under controlled IOP. Conclusions The neuroprotective effect of losartan in mouse glaucoma is associated with adaptive changes in the sclera expressed at the optic nerve head. PMID:26505191

Bilateral optic disc drusen mimicking papilledema.

PubMed

Sahin, Alparslan; Cingü, Abdullah Kürşat; Ari, Seyhmus; Cinar, Yasin; Caça, Ihsan

2012-06-01

Optic disc drusen, which are calcified deposits that form anterior to the lamina cribrosa in the optic nerve, may mimic papilledema. We report herein three cases referred to us with suspicion of disc swelling and papilledema. Following ophthalmologic evaluation with B-scan ultrasound, red-free fundus photography, and computed tomography, the diagnosis of papilledema was excluded in all cases and optic disc drusen was diagnosed. Clinical suspicion of optic disc drusen in cases presenting with swelling of the optic nerve head is important in order to avoid unnecessary interventions and anxiety. The reported cases highlight the commonly encountered clinical presentations and the practical aspects of diagnosis and management of optic disc drusen.

Hydrogen-rich saline promotes survival of retinal ganglion cells in a rat model of optic nerve crush.

PubMed

Sun, Jing-chuan; Xu, Tao; Zuo, Qiao; Wang, Ruo-bing; Qi, Ai-qing; Cao, Wen-luo; Sun, Ai-jun; Sun, Xue-jun; Xu, Jiajun

2014-01-01

To investigate the effect of molecular hydrogen (H2) in a rat model subjected to optic nerve crush (ONC). We tested the hypothesis that after optic nerve crush (ONC), retinal ganglion cell (RGC) could be protected by H₂. Rats in different groups received saline or hydrogen-rich saline every day for 14 days after ONC. Retinas from animals in each group underwent measurements of hematoxylin and eosin (H&E) staining, cholera toxin beta (CTB) tracing, gamma synuclein staining, and terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling (TUNEL) staining 2 weeks post operation. Flash visual evoked potentials (FVEP) and pupillary light reflex (PLR) were then tested to evaluate the function of optic nerve. The malondialdehyde (MDA) level in retina was evaluated. H&E, gamma synuclein staining and CTB tracing showed that the survival rate of RGCs in hydrogen saline-treated group was significantly higher than that in saline-treated group. Apoptosis of RGCs assessed by TUNEL staining were less observed in hydrogen saline-treated group. The MDA level in retina of H₂ group was much lower than that in placebo group. Furthermore, animals treated with hydrogen saline showed better function of optic nerve in assessments of FVEP and PLR. These results demonstrated that H₂ protects RGCs and helps preserve the visual function after ONC and had a neuroprotective effect in a rat model subjected to ONC.

Radiation treatment inhibits monocyte entry into the optic nerve head and prevents neuronal damage in a mouse model of glaucoma

PubMed Central

Howell, Gareth R.; Soto, Ileana; Zhu, Xianjun; Ryan, Margaret; Macalinao, Danilo G.; Sousa, Gregory L.; Caddle, Lura B.; MacNicoll, Katharine H.; Barbay, Jessica M.; Porciatti, Vittorio; Anderson, Michael G.; Smith, Richard S.; Clark, Abbot F.; Libby, Richard T.; John, Simon W.M.

2012-01-01

Glaucoma is a common ocular disorder that is a leading cause of blindness worldwide. It is characterized by the dysfunction and loss of retinal ganglion cells (RGCs). Although many studies have implicated various molecules in glaucoma, no mechanism has been shown to be responsible for the earliest detectable damage to RGCs and their axons in the optic nerve. Here, we show that the leukocyte transendothelial migration pathway is activated in the optic nerve head at the earliest stages of disease in an inherited mouse model of glaucoma. This resulted in proinflammatory monocytes entering the optic nerve prior to detectable neuronal damage. A 1-time x-ray treatment prevented monocyte entry and subsequent glaucomatous damage. A single x-ray treatment of an individual eye in young mice provided that eye with long-term protection from glaucoma but had no effect on the contralateral eye. Localized radiation treatment prevented detectable neuronal damage and dysfunction in treated eyes, despite the continued presence of other glaucomatous stresses and signaling pathways. Injection of endothelin-2, a damaging mediator produced by the monocytes, into irradiated eyes, combined with the other glaucomatous stresses, restored neural damage with a topography characteristic of glaucoma. Together, these data support a model of glaucomatous damage involving monocyte entry into the optic nerve. PMID:22426214

The Columbia Thyroid Eye Disease-Compressive Optic Neuropathy Formula.

PubMed

Callahan, Alison B; Campbell, Ashley A; Oropesa, Susel; Baraban, Aryeh; Kazim, Michael

2018-06-13

Diagnosing thyroid eye disease-compressive optic neuropathy (TED-CON) is challenging, particularly in cases lacking a relative afferent pupillary defect. Large case series of TED-CON patients and accessible diagnostic tools are lacking in the current literature. This study aims to create a mathematical formula that accurately predicts the presence or absence of CON based on the most salient clinical measures of optic neuropathy. A retrospective case series compares 108 patients (216 orbits) with either unilateral or bilateral TED-CON and 41 age-matched patients (82 orbits) with noncompressive TED. Utilizing clinical variables assessing optic nerve function and/or risk of compressive disease, and with the aid of generalized linear regression modeling, the authors create a mathematical formula that weighs the relative contribution of each clinical variable in the overall prediction of CON. Data from 213 orbits in 110 patients derived the formula: y = -0.69 + 2.58 × (afferent pupillary defect) - 0.31 × (summed limitation of ductions) - 0.2 × (mean deviation on Humphrey visual field testing) - 0.02 × (% color plates). This accurately predicted the presence of CON (y > 0) versus non-CON (y < 0) in 82% of cases with 83% sensitivity and 81% specificity. When there was no relative afferent pupillary defect, which was the case in 63% of CON orbits, the formula correctly predicted CON in 78% of orbits with 73% sensitivity and 83% specificity. The authors developed a mathematical formula, the Columbia TED-CON Formula (CTD Formula), that can help guide clinicians in accurately diagnosing TED-CON, particularly in the presence of bilateral disease and when no relative afferent pupillary defect is present.

Synchronous electrical stimulation of laryngeal muscles: an alternative for enhancing recovery of unilateral recurrent laryngeal nerve paralysis.

PubMed

Garcia Perez, Alejandro; Hernández López, Xochiquetzal; Valadez Jiménez, Víctor Manuel; Minor Martínez, Arturo; Ysunza, Pablo Antonio

2014-07-01

Although electrical stimulation of the larynx has been widely studied for treating voice disorders, its effectiveness has not been assessed under safety and comfortable conditions. This article describes design, theoretical issues, and preliminary evaluation of an innovative system for transdermal electrical stimulation of the larynx. The proposed design includes synchronization of electrical stimuli with laryngeal neuromuscular activity. To study whether synchronous electrical stimulation of the larynx could be helpful for improving voice quality in patients with dysphonia due to unilateral recurrent laryngeal nerve paralysis (URLNP). A 3-year prospective study was carried out at the Instituto Nacional de Rehabilitacion in the Mexico City. Ten patients were subjected to transdermal current electrical stimulation synchronized with the fundamental frequency of the vibration of the vocal folds during phonation. The stimulation was triggered during the phase of maximum glottal occlusion. A complete acoustic voice analysis was performed before and after the period of electrical stimulation. Acoustic analysis revealed significant improvements in all parameters after the stimulation period. Transdermal synchronous electrical stimulation of vocal folds seems to be a safe and reliable procedure for enhancing voice quality in patients with (URLNP). Copyright © 2014 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Cooperative hand movements in post-stroke subjects: Neural reorganization.

PubMed

Schrafl-Altermatt, Miriam; Dietz, Volker

2016-01-01

Recent research indicates a task-specific neural coupling controlling cooperative hand movements reflected in bilateral electromyographic reflex responses in arm muscles following unilateral nerve stimulation. Reorganization of this mechanism was explored in post-stroke patients in this study. Electromyographic reflex responses in forearm muscles to unilateral electrical ulnar nerve stimulation were examined during cooperative and non-cooperative hand movements. Stimulation of the unaffected arm during cooperative hand movements led to electromyographic responses in bilateral forearm muscles, similar to those seen in healthy subjects, while stimulation of the affected side was followed only by ipsilateral responses. No contralateral reflex responses could be evoked in severely affected patients. The presence of contralateral responses correlated with the clinical motor impairment as assessed by the Fugl-Meyer test. The observations suggest that after stroke an impaired processing of afferent input from the affected side leads to a defective neural coupling and is associated with a greater involvement of fiber tracts from the unaffected hemisphere during cooperative hand movements. The mechanism of neural coupling underlying cooperative hand movements is shown to be defective in post-stroke patients. The neural re-organizations observed have consequences for the rehabilitation of hand function. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Outcomes of Laryngeal Reinnervation for Unilateral Vocal Fold Paralysis in Children: Associations With Age and Time Since Injury.

PubMed

Smith, Marshall E; Houtz, Daniel R

2016-05-01

Outcomes of laryngeal reinnervation with ansa-cervicalis for unilateral vocal fold paralysis (UVFP) may be influenced by age of the patient and time interval between laryngeal nerve injury and reinnervation, suggesting less favorable outcomes in older patients and greater than 2-year time interval after injury. This study examines these issues in the pediatric population. Review of prospectively collected data set of 35 children and adolescents (1-21 years) that underwent ansa-recurrent laryngeal nerve (RLN) laryngeal reinnervation for UVFP. The time from RLN injury to reinnervation averaged 5.0 years (range, 0.8-15.2 years). No correlation was found between age at reinnervation (r = 0.15) and patient- or parent-reported global percentage voice outcome or perceptual ratings. There was slight negative correlation in duration between RLN injury and reinnervation and voice outcomes (r = -0.31). Postoperative voice self/surrogate global percentage rating average was 80.5% (range, 50%-100%), and perceptual rating GRBAS sum score average was 2.9 (range, 0-7). In pediatric ansa-RLN reinnervation for UVFP, no correlation between age at surgery and postoperative outcome was found. Denervation duration showed slight negative correlation, similar to what has been reported in adults, though voice improvement was seen in all patients. © The Author(s) 2015.

Reinnervation of the diaphragm by the inferior laryngeal nerve to the phrenic nerve in ventilator-dependent tetraplegic patients with C3-5 damage.

PubMed

Verin, Eric; Morelot-Panzini, Capucine; Gonzalez-Bermejo, Jesus; Veber, Benoit; Perrouin Verbe, Brigitte; Soudrie, Brigitte; Leroi, Anne Marie; Marie, Jean Paul; Similowski, Thomas

2017-10-01

The aim of this study was to evaluate the feasibility of unilateral diaphragmatic reinnervation in humans by the inferior laryngeal nerve. This pilot study included chronically ventilated tetraplegic patients with destruction of phrenic nerve motoneurons. Five patients were included. They all had a high level of tetraplegia, with phrenic nerve motor neuron destruction. They were highly dependent on ventilation, without any possibility of weaning. They did not have other chronic pathologies, especially laryngeal disease. They all had diaphragmatic explorations to diagnose the destruction of the motoneurons of the phrenic nerves and nasoendoscopy to be sure that they did not have laryngeal or pharyngeal disease. Then, surgical anastomosis of the right phrenic nerve was performed with the inferior laryngeal nerve, by a cervical approach. A laryngeal reinnervation was performed at the same time, using the ansa hypoglossi. One patient was excluded because of a functional phrenic nerve and one patient died 6 months after the surgery of a cardiac arrest. The remaining three patients were evaluated after the anastomosis every 6 months. They did not present any swallowing or vocal alterations. In these three patients, the diaphragmatic explorations showed that there was a recovery of the diaphragmatic electromyogram of the right and left hemidiaphragms after 1 year. Two patients had surgical diaphragmatic explorations for diaphragmatic pacing 18-24 months after the reinnervation with excellent results. At 36 months, none of the patients could restore their automatic ventilation. In conclusion, this study demonstrated that diaphragmatic reinnervation by the inferior laryngeal nerve is effective, without any vocal or swallowing complications.

Reinnervation of the diaphragm by the inferior laryngeal nerve to the phrenic nerve in ventilator-dependent tetraplegic patients with C3-5 damage

PubMed Central

Morelot-Panzini, Capucine; Gonzalez-Bermejo, Jesus; Veber, Benoit; Perrouin Verbe, Brigitte; Soudrie, Brigitte; Leroi, Anne Marie; Marie, Jean Paul; Similowski, Thomas

2017-01-01

The aim of this study was to evaluate the feasibility of unilateral diaphragmatic reinnervation in humans by the inferior laryngeal nerve. This pilot study included chronically ventilated tetraplegic patients with destruction of phrenic nerve motoneurons. Five patients were included. They all had a high level of tetraplegia, with phrenic nerve motor neuron destruction. They were highly dependent on ventilation, without any possibility of weaning. They did not have other chronic pathologies, especially laryngeal disease. They all had diaphragmatic explorations to diagnose the destruction of the motoneurons of the phrenic nerves and nasoendoscopy to be sure that they did not have laryngeal or pharyngeal disease. Then, surgical anastomosis of the right phrenic nerve was performed with the inferior laryngeal nerve, by a cervical approach. A laryngeal reinnervation was performed at the same time, using the ansa hypoglossi. One patient was excluded because of a functional phrenic nerve and one patient died 6 months after the surgery of a cardiac arrest. The remaining three patients were evaluated after the anastomosis every 6 months. They did not present any swallowing or vocal alterations. In these three patients, the diaphragmatic explorations showed that there was a recovery of the diaphragmatic electromyogram of the right and left hemidiaphragms after 1 year. Two patients had surgical diaphragmatic explorations for diaphragmatic pacing 18–24 months after the reinnervation with excellent results. At 36 months, none of the patients could restore their automatic ventilation. In conclusion, this study demonstrated that diaphragmatic reinnervation by the inferior laryngeal nerve is effective, without any vocal or swallowing complications. PMID:29181382

[Nonarteritic ischemic optic neuropathy animal model and its treatment applications].

PubMed

Chuman, Hideki

2014-04-01

Nonarteritic ischemic optic neuropathy (NAION) is one of the most common acute unilaterally onset optic nerve diseases. One management problem in terms of NAION is the difficulty of differential diagnosis between NAION and anterior optic neuritis (ON). A second problem is that there is no established treatment for the acute stage of NAION. A third problem is that there is no preventive treatment for a subsequent attack on the fellow eye, estimated to occur in 15 to 25% of patients with NAION. For differentiation of acute NAION from anterior optic neuritis, we investigated the usefulness of laser speckle flowgraphy (LSFG). In the normal control group, the tissue blood flow did not significantly differ between the right and left eyes. In the NAION group, all 6 patients had 29.5% decreased mean blur rate (MBR), which correlates to optic disc blood flow, of the NAION eye compared with the unaffected eye. In the anterior ON group, all 6 cases had 15.9% increased MBR of the anterior ON eye compared with the unaffected eye. Thus, LSFG showed a difference of the underlying pathophysiology between NAION and anterior ON despite showing disc swelling in both groups and could be useful for differentiating both groups. For the treatment of acute stage of NAION, we tried to reproduce the rodent model of NAION (rNAION) developed by Bernstein and colleagues. To induce rNAION, after the administration of rose bengal(RB) (2.5 mM) into the tail vein of SD rats, the small vessels of the left optic nerve were photoactivated using a 514 nm argon green laser (RB-laser-induction). In the RB-laser-induction eyes, the capillaries within the optic disc were reduced markedly, the optic disc became swollen, and fluorescein angiography showed filling defect in the choroid and the optic disc at an early stage, followed by hyperfluorescence at a late stage. Electrophysiological evaluation revealed that visual evoked potential (VEP) amplitude was significantly decreased but an electroretinogram (ERG) did not show a significant difference either in the b wave or in the oscillatory potentials. The scotopic threshold response (STR) was significantly reduced 3 days after induction. These findings are similar to those of rNAION and indicate that we succeeded in reproducing the rNAION. Histopathologic examination in the acute phase of rNAION, showed acellular NFL swelling anterior to the optic disc. No accumulation of inflammatory cells was noted in several microscopic sections of the optic nerve. In addition, immunochemical staining was negative throughout the retina and optic nerve. These results suggested that the rNAION-induced NFL swelling was not a result of inflammation. In the chronic phase of rNAION, the morphologic retinal changes were apparent in only the retinal ganglion cell(RGC) layer, with a reduction in the number of cells in the RGC layer. Thus, we need to evaluate the degree of the NFL swelling in the acute phase and the following thinning of the NFL in the chronic phase for efficacy of the treatment of rNAION. Therefore, we used optical coherence tomography (OCT) for the objective and quantitative evaluation of the retinal nerve fiber layer (RNFL) thickness around the optic disc changes in rNAION. The second method was to use the STR for the evaluation of the RGC function. The third method was to count the number of surviving RGCs observed and photographed through the fluorescence microscope with the Fluorogold staining. A possible rationale for treatment of NAION is that dilation of the posterior ciliary artery (PCA) increases the blood flow to the optic nerve and could improve the optic nerve function. To clarify the vasodilatory effects of medications, we used in vitro isometric tension recording methods and examined the vasodilatory effects of bevacizumab as an anti-vascular endothelial growth factor (VEGF) antibody, methylprednisolone as a corticosteroid and sodium nitroprusside (SNP, a nitric oxide donor) as a vasodilator on high-K (potassium) solution-induced contraction in isolated rabbit PCA. Bevacizumab did not relax rabbit PCA. Methylprednisolone relaxed rabbit PCA nitric oxide (NO) independently. SNP relaxed rabbit PCA by exogenous NO. On the basis of these results, we selected the following candidates for rNAION treatment: methylprednisolone as the corticosteroid and L-arginine as the NO related agent. Intravenous infusion of methylprednisolone significantly decreased the degree of acute disc edema but did not reduce inner retinal thinning, decrease STR amplitude, or decrease RGC numbers in rNAION. Intravenous infusion of L-arginine after rNAION induction significantly decreased the disc edema at the acute stage and the thinning of the inner retina, reduced the decrease in STR amplitude, and reduced the decrease in RGC numbers during rNAION. These results indicated that L-arginine treatment is effective for reducing the anatomical changes and improving visual function in the acute stage of rNAION. To strengthen the neuroprotective effect for rNAION, we tried treatment using transcorneal electric stimulation (TES). We evaluated the effect using STR and survival RGCs. Decreased amplitude in the STR of the TES group was significantly better preserved than in the control group on the 28th day after treatment. RGC survival in the TES group was significantly larger than in the control group on the 14th and 28th days. The neuroprotective effect of TES was better than that of L-arginine. For preventive treatment of subsequent attack in the fellow eye, we investigated whether pretreatment with L-arginine might reduce the severity of the anatomical changes associated with NAION and preserve the visual function when NAION occurs in the other eye. In the L-arginine pretreated eyes, the disc edema at the acute stage and the thinning of inner retina were significantly decreased, and the decrease of STR amplitude and the decrease in RGC numbers during rNAION were reserved. These results indicate that pretreatment with L-arginine is effective for the reduction of the severity during recurrence in the other eye. We will perform clinical trials in a small series of cases, and if the treatment is effective, we will proceed to multicenter randomized treatment trials. In addition to that, more work needs to be done to discover better treatment options for NAION.

Ultra-High Resolution Optical Coherence Tomography Imaging of Unilateral Drusen in a 31 Year Old Woman.

PubMed

de Carlo, Talisa E; Adhi, Mehreen; Lu, Chen D; Duker, Jay S; Fujimoto, James G; Waheed, Nadia K

We report a case of widespread unilateral drusen in a healthy 31 year old Caucasian woman using multi-modal imaging including ultra-high resolution optical coherence tomography (UHR-OCT). Dilated fundus exam showed multiple drusen-like lesions in the posterior pole without heme or fluid. Fundus auto fluorescence demonstrated hyperautofluorescent at the deposits. Fluorescein angiography revealed mild hyperfluorescence and staining of the lesions. Spectral-domain optical coherence tomography (SD-OCT) OS showed accumulations in the temporal macula at Bruch's membrane. UHR-OCT provided improved axial resolution compared to the standard 5 μm on the commercial SD-OCT and confirmed the presence of deposits in Bruch's membrane, consistent with drusen. The retinal layers were draped over the excrescences but did not show any disruption.

Pilot Study of Optical Coherence Tomography Measurement of Retinal Blood Flow in Retinal and Optic Nerve Diseases

PubMed Central

Wang, Yimin; Fawzi, Amani A.; Varma, Rohit; Sadun, Alfredo A.; Zhang, Xinbo; Tan, Ou; Izatt, Joseph A.

2011-01-01

Purpose. To investigate blood flow changes in retinal and optic nerve diseases with Doppler Fourier domain optical coherence tomography (OCT). Methods. Sixty-two participants were divided into five groups: normal, glaucoma, nonarteritic ischemic optic neuropathy (NAION), treated proliferative diabetic retinopathy (PDR), and branch retinal vein occlusion (BRVO). Doppler OCT was used to scan concentric circles of 3.4- and 3.75-mm diameters around the optic nerve head. Flow in retinal veins was calculated from the OCT velocity profiles. Arterial and venous diameters were measured from OCT Doppler and reflectance images. Results. Total retinal blood flow in normal subjects averaged 47.6 μL/min. The coefficient of variation of repeated measurements was 11% in normal eyes and 14% in diseased eyes. Eyes with glaucoma, NAION, treated PDR, and BRVO had significantly decreased retinal blood flow compared with normal eyes (P < 0.001). In glaucoma patients, the decrease in blood flow was highly correlated with the severity of visual field loss (P = 0.003). In NAION and BRVO patients, the hemisphere with more severe disease also had lower blood flow. Conclusions. Doppler OCT retinal blood flow measurements showed good repeatability and excellent correlation with visual field and clinical presentations. This approach could enhance our understanding of retinal and optic nerve diseases and facilitate the development of new therapies. PMID:21051715

Optical coherence tomography measurement of the retinal nerve fiber layer in normal and juvenile glaucomatous eyes.

PubMed

Mrugacz, Malgorzata; Bakunowicz-Lazarczyk, Alina

2005-01-01

The aim of this study was to quantitatively assess and compare the thickness of the retinal nerve fiber layer (RNFL) in normal and glaucomatous eyes of children using the optical coherence tomograph. The mean RNFL thickness of normal eyes (n=26) was compared with that of glaucomatous eyes (n=26). The eyes were classified into diagnostic groups based on conventional ophthalmological physical examination, Humphrey 30-2 visual fields, stereoscopic optic nerve head photography, and optical coherence tomography. The mean RNFL was significantly thinner in glaucomatous eyes than in normal eyes: 95+/-26.3 and 132+/-24.5 microm, respectively. More specifically, the RNFL was significantly thinner in glaucomatous eyes than in normal eyes in the inferior quadrant: 87+/-23.5 and 122+/-24.2 microm, respectively. The mean and inferior quadrant RFNL thicknesses as measured by the optical coherence tomograph showed a statistically significant correlation with glaucoma. Optical coherence tomography may contribute to tracking of juvenile glaucoma progression. Copyright (c) 2005 S. Karger AG, Basel.

Stereotactic radiotherapy for malignancies involving the trigeminal and facial nerves.

PubMed

Cuneo, K C; Zagar, T M; Brizel, D M; Yoo, D S; Hoang, J K; Chang, Z; Wang, Z; Yin, F F; Das, S K; Green, S; Ready, N; Bhatti, M T; Kaylie, D M; Becker, A; Sampson, J H; Kirkpatrick, J P

2012-06-01

Involvement of a cranial nerve caries a poor prognosis for many malignancies. Recurrent or residual disease in the trigeminal or facial nerve after primary therapy poses a challenge due to the location of the nerve in the skull base, the proximity to the brain, brainstem, cavernous sinus, and optic apparatus and the resulting complex geometry. Surgical resection caries a high risk of morbidity and is often not an option for these patients. Stereotactic radiosurgery and radiotherapy are potential treatment options for patients with cancer involving the trigeminal or facial nerve. These techniques can deliver high doses of radiation to complex volumes while sparing adjacent critical structures. In the current study, seven cases of cancer involving the trigeminal or facial nerve are presented. These patients had unresectable recurrent or residual disease after definitive local therapy. Each patient was treated with stereotactic radiation therapy using a linear accelerator based system. A multidisciplinary approach including neuroradiology and surgical oncology was used to delineate target volumes. Treatment was well tolerated with no acute grade 3 or higher toxicity. One patient who was reirradiated experienced cerebral radionecrosis with mild symptoms. Four of the seven patients treated had no evidence of disease after a median follow up of 12 months (range 2-24 months). A dosimetric analysis was performed to compare intensity modulated fractionated stereotactic radiation therapy (IM-FSRT) to a 3D conformal technique. The dose to 90% (D90) of the brainstem was lower with the IM-FSRT plan by a mean of 13.5 Gy. The D95 to the ipsilateral optic nerve was also reduced with IM-FSRT by 12.2 Gy and the D95 for the optic chiasm was lower with FSRT by 16.3 Gy. Treatment of malignancies involving a cranial nerve requires a multidisciplinary approach. Use of an IM-FSRT technique with a micro-multileaf collimator resulted in a lower dose to the brainstem, optic nerves and chiasm for each case examined.

White matter changes linked to visual recovery after nerve decompression

PubMed Central

Paul, David A.; Gaffin-Cahn, Elon; Hintz, Eric B.; Adeclat, Giscard J.; Zhu, Tong; Williams, Zoë R.; Vates, G. Edward; Mahon, Bradford Z.

2015-01-01

The relationship between the integrity of white matter tracts and cortical function in the human brain remains poorly understood. Here we use a model of reversible white matter injury, compression of the optic chiasm by tumors of the pituitary gland, to study the structural and functional changes that attend spontaneous recovery of cortical function and visual abilities after surgical tumor removal and subsequent decompression of the nerves. We show that compression of the optic chiasm leads to demyelination of the optic tracts, which reverses as quickly as 4 weeks after nerve decompression. Furthermore, variability across patients in the severity of demyelination in the optic tracts predicts visual ability and functional activity in early cortical visual areas, and pre-operative measurements of myelination in the optic tracts predicts the magnitude of visual recovery after surgery. These data indicate that rapid regeneration of myelin in the human brain is a significant component of the normalization of cortical activity, and ultimately the recovery of sensory and cognitive function, after nerve decompression. More generally, our findings demonstrate the utility of diffusion tensor imaging as an in vivo measure of myelination in the human brain. PMID:25504884

Comparative quantitative study of astrocytes and capillary distribution in optic nerve laminar regions.

PubMed

Balaratnasingam, Chandrakumar; Kang, Min H; Yu, Paula; Chan, Geoffrey; Morgan, William H; Cringle, Stephen J; Yu, Dao-Yi

2014-04-01

Retinal ganglion cell (RGC) axonal structure and function in the optic nerve head (ONH) is predominantly supported by astrocytes and capillaries. There is good experimental evidence to demonstrate that RGC axons are perturbed in a non-uniform manner following ONH injury and it is likely that the pattern of RGC axonal modification bears some correlation with the quantitative properties of astrocytes and capillaries within laminar compartments. Although there have been some excellent topographic studies concerning glial and microvascular networks in the ONH our knowledge regarding the quantitative properties of these structures are limited. This report is an in-depth quantitative, structural analysis of astrocytes and capillaries in the pre laminar, lamina cribrosa and post laminar compartments of the ONH. 49 optic nerves from human (n = 10), pig (n = 12), horse (n = 6), rat (n = 11) and rabbit (n = 10) eyes are studied. Immunohistochemical and high-magnification confocal microscopy techniques are used to co-localise astrocytes, capillaries and nuclei in the mid-portion of the optic nerve. Quantitative methodology is used to determine the area occupied by astrocyte processes, microglia processes, nuclei density and the area occupied by capillaries in each laminar compartment. Comparisons are made within and between species. Relationships between ONH histomorphometry and astrocyte-capillary constitution are also explored. This study demonstrates that there are significant differences in the quantitative properties of capillaries and astrocytes between the laminar compartments of the human ONH. Astrocyte processes occupied the greatest area in the lamina cribrosa compartment of the human ONH implicating it as an area of great metabolic demands. Microglia were found to occupy only a small proportion of tissue in the rat, rabbit and pig optic nerve suggesting that the astrocyte is the predominant glia cell type in the optic nerve. This study also demonstrates that there is significant uniformity, with respect to astrocyte and capillary constitution, in the post laminar region of species with an unmyelinated anterior optic nerve. This implicates an important role served by oligodendrocytes and myelin in governing the structural characteristics of the post laminar optic nerve. Finally, this study demonstrates that eyes with similar lamina cribrosa structure do not necessarily share an identical cellular constitution with respect to astrocytes. The quantitative properties of astrocytes in the pre laminar and lamina cribrosa regions of the rat, which has a rudimentary lamina cribrosa with only a few collagenous beams, shared more similarities to the human eye than the pig or horse. The quantitative properties of astrocytes and capillaries in the laminar compartments of the ONH provide a basis for understanding the pathogenic mechanisms that are involved in diseases such as glaucoma and ischemic optic neuropathy. The findings in this study also provide valuable information about the distinct advantages of different animal models for studying human optic nerve diseases. Utilisation of structural data provided in this report together with emerging in vivo technology may potentially permit the early identification of RGC axonal injury by quantifying changes in ONH capillaries and astrocytes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Virtual tissue engineering and optic pathways: plotting the course of the axons in the retinal nerve fiber layer.

PubMed

Carreras, Francisco Javier; Medina, Javier; Ruiz-Lozano, Mariola; Carreras, Ignacio; Castro, Juan Luis

2014-04-17

As part of a larger project on virtual tissue engineering of the optic pathways, we describe the conditions that guide axons extending from the retina to the optic nerve head and formulate algorithms that meet such conditions. To find the entrance site on the optic nerve head of each axon, we challenge the fibers to comply with current models of axonal pathfinding. First, we build a retinal map using a single type of retinal ganglion cell (RGC) using density functions from the literature. Dendritic arbors are equated to receptive fields. Shape and size of retinal surface and optic nerve head (ONH) are defined. A computer model relates each soma to the corresponding entry point of its axon into the optic disc. Weights are given to the heuristics that guide the preference entry order in the nerve. Retinal ganglion cells from the area centralis saturate the temporal section of the disc. Retinal ganglion cells temporal to the area centralis curve their paths surrounding the fovea; some of these cells enter the disc centrally rather than peripherally. Nasal regions of the disc receive mixed axons from the far periphery of the temporal hemiretina, together with axons from the nasal half. The model plots the course of the axon using Bezier curves and compares them with clinical data, for a coincidence level of 86% or higher. Our model is able to simulate basic data of the early optic pathways including certain singularities and to mimic mechanisms operating during development, such as timing and fasciculation. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

An Unusual Case Report of Bertolotti's Syndrome: Extraforaminal Stenosis and L5 Unilateral Root Compression (Castellvi Type III an LSTV).

PubMed

Kapetanakis, Stylianos; Chaniotakis, Constantinos; Paraskevopoulos, Constantinos; Pavlidis, Pavlos

2017-01-01

Castellvi Type III lumbosacral transitional vertebrae (LSTV) is an unusual case of Bertolotti's syndrome (BS) due to extraforaminal stenosis, especially manifesting in elderly patients. We report a case of BS in a 62 years old Greek female. The signs of the clinical examination are low back pain, sciatica, hypoesthesia, and pain to the contribution of L5 nerve. Imaging techniques revealed an LSTV Type III a (complete sacralization between LSTV and sacrum). Despite the fact that LSTV is a congenital lesion, the clinical manifestation of BS may present in the elderly population. The accumulative effect of the gradual degeneration of intervertebral foramen (stenosis) may lead to the compression of extraforaminal portion of the nerve root.

High-Resolution Imaging of the Optic Nerve and Retina in Optic Nerve Hypoplasia

PubMed Central

Pilat, Anastasia; Sibley, Daniel; McLean, Rebecca J.; Proudlock, Frank A.; Gottlob, Irene

2015-01-01

Purpose To investigate the optic nerve and macular morphology in patients with optic nerve hypoplasia (ONH) using spectral-domain optical coherence tomography (SD OCT). Design Prospective, cross-sectional, observational study. Subjects A total of 16 participants with ONH (10 female and 6 male; mean age, 17.2 years; 6 bilateral involvement) and 32 gender-, age-, ethnicity-, and refraction-matched healthy controls. Methods High-resolution SD OCT (Copernicus [Optopol Technology S.A., Zawiercie, Poland], 3 μm resolution) and handheld SD OCT (Bioptigen Inc [Research Triangle Park, NC], 2.6 μm resolution) devices were used to acquire horizontal scans through the center of the optic disc and macula. Main Outcome Measures Horizontal optic disc/cup and rim diameters, cup depth, peripapillary retinal nerve fiber layer (RNFL), and thickness of individual retinal layers in participants with ONH and in controls. Results Patients with ONH had significantly smaller discs (P < 0.03 and P < 0.001 compared with unaffected eye and healthy controls, respectively), horizontal cup diameter (P < 0.02 for both), and cup depth (P < 0.02 and P < 0.01, respectively). In the macula, significantly thinner RNFL (nasally), ganglion cell layer (GCL) (nasally and temporally), inner plexiform layer (IPL) (nasally), outer nuclear layer (ONL) (nasally), and inner segment (centrally and temporally) were found in patients with ONH compared with the control group (P < 0.05 for all comparisons). Continuation of significantly thicker GCL, IPL, and outer plexiform layer in the central retinal area (i.e., foveal hypoplasia) was found in more than 80% of patients with ONH. Clinically unaffected fellow eyes of patients with ONH showed mild features of underdevelopment. Visual acuity and presence of septo-optic dysplasia were associated with changes in GCL and IPL. Sensitivity and specificity for the detection of ONH based on disc and retinal optical coherence tomography (OCT) parameters were >80%. Conclusions Our study provides evidence of retinal changes in ONH. In addition to thinning of retina layers mainly involving the RNFL and GCL, signs reminiscent of foveal hypoplasia were observed in patients with ONH. Optic nerve and foveal parameters measured using OCT showed high sensitivity and specificity for detecting ONH, demonstrating their useful for clinical diagnosis. PMID:25939636

Optic neuropathies: the tip of the neurodegeneration iceberg

PubMed Central

Carelli, Valerio; La Morgia, Chiara; Ross-Cisneros, Fred N.; Sadun, Alfredo A.

2017-01-01

Abstract The optic nerve and the cells that give origin to its 1.2 million axons, the retinal ganglion cells (RGCs), are particularly vulnerable to neurodegeneration related to mitochondrial dysfunction. Optic neuropathies may range from non-syndromic genetic entities, to rare syndromic multisystem diseases with optic atrophy such as mitochondrial encephalomyopathies, to age-related neurodegenerative diseases such as Alzheimer’s and Parkinson’s disease where optic nerve involvement has, until recently, been a relatively overlooked feature. New tools are available to thoroughly investigate optic nerve function, allowing unparalleled access to this part of the central nervous system. Understanding the molecular pathophysiology of RGC neurodegeneration and optic atrophy, is key to broadly understanding the pathogenesis of neurodegenerative disorders, for monitoring their progression in describing the natural history, and ultimately as outcome measures to evaluate therapies. In this review, the different layers, from molecular to anatomical, that may contribute to RGC neurodegeneration and optic atrophy are tackled in an integrated way, considering all relevant players. These include RGC dendrites, cell bodies and axons, the unmyelinated retinal nerve fiber layer and the myelinated post-laminar axons, as well as olygodendrocytes and astrocytes, looked for unconventional functions. Dysfunctional mitochondrial dynamics, transport, homeostatic control of mitobiogenesis and mitophagic removal, as well as specific propensity to apoptosis may target differently cell types and anatomical settings. Ultimately, we can envisage new investigative approaches and therapeutic options that will speed the early diagnosis of neurodegenerative diseases and their cure. PMID:28977448

A photon-driven micromotor can direct nerve fibre growth

NASA Astrophysics Data System (ADS)

Wu, Tao; Nieminen, Timo A.; Mohanty, Samarendra; Miotke, Jill; Meyer, Ronald L.; Rubinsztein-Dunlop, Halina; Berns, Michael W.

2012-01-01

Axonal path-finding is important in the development of the nervous system, nerve repair and nerve regeneration. The behaviour of the growth cone at the tip of the growing axon determines the direction of axonal growth and migration. We have developed an optical-based system to control the direction of growth of individual axons (nerve fibres) using laser-driven spinning birefringent spheres. One or two optical traps position birefringent beads adjacent to growth cones of cultured goldfish retinal ganglion cell axons. Circularly polarized light with angular momentum causes the trapped bead to spin. This creates a localized microfluidic flow generating an estimated 0.17 pN shear force against the growth cone that turns in response to the shear. The direction of axonal growth can be precisely manipulated by changing the rotation direction and position of this optically driven micromotor. A physical model estimating the shear force density on the axon is described.

Optical coherence tomography detects characteristic retinal nerve fiber layer thickness corresponding to band atrophy of the optic discs.

PubMed

Kanamori, Akiyasu; Nakamura, Makoto; Matsui, Noriko; Nagai, Azusa; Nakanishi, Yoriko; Kusuhara, Sentaro; Yamada, Yuko; Negi, Akira

2004-12-01

To analyze retinal nerve fiber layer (RNFL) thickness in eyes with band atrophy by use of optical coherence tomography (OCT) and to evaluate the ability of OCT to detect this characteristic pattern of RNFL loss. Cross-sectional, retrospective study. Thirty-four eyes of 18 patients with bitemporal hemianopia caused by optic chiasm compression by chiasmal tumors were studied. All eyes were divided into 3 groups according to visual field loss grading after Goldmann perimetry. Retinal nerve fiber layer thickness measurements with OCT. Retinal nerve fiber layer thickness around the optic disc was measured by OCT (3.4-mm diameter circle). Calculation of the changes in OCT parameters, including the horizontal (nasal + temporal quadrant RNFL thickness) and vertical values (superior + inferior quadrant RNFL thickness) was based on data from 160 normal eyes. Comparison between the 3 visual field grading groups was done with the analysis of variance test. The receiver operating characteristic (ROC) curve for the horizontal and vertical value were calculated, and the areas under the curve (AUC) were compared. Retinal nerve fiber layer thickness in eyes with band atrophy decreased in all OCT parameters. The reduction rate in average and temporal RNFL thickness and horizontal value was correlated with visual field grading. The AUC of horizontal value was 0.970+/-0.011, which was significantly different from AUC of vertical value (0.903+/-0.022). The degree of RNFL thickness reduction correlated with that of visual field defects. Optical coherence tomography was able to identify the characteristic pattern of RNFL loss in these eyes.

Non-Recurrent Laryngeal Nerve.

PubMed

Buła, Grzegorz; Mucha, Ryszard; Paliga, Michał; Koziołek, Henryk; Niedzielski, Zbigniew; Gawrychowski, Jacek

2015-07-01

The aim of the study was to assess the frequency of non-recurrent laryngeal nerves (Non-RLN). A total of 6110 patients were operated in our hospital between 1 January 2005 and 31 December 2013 for various goiters (5429) and various types of hyperparathyroidism (618). Laryngeal nerve was exposed during operation in 1700 patients from superior aperture of the chest to superior aperture of the larynx. Identification process of RLN was started with dissecting inferior thyroid artery (ITA) and its junction with the nerve. Then main trunk of the nerve was exposed backwards till the region of superior aperture of the chest together with the end portion till the nerve outlet to the larynx. In the group of 1700 patients, RLN was exposed bilaterally in 1400 (82.4%) and unilaterally in 300 (17.6%). In the group of 3100 dissected RLNs the course of RLN was observed on the right side in 1710 patients and on the left in 1390. Irreversible nature RLN was shown in four cases (0.1%) - four women (02%) aged 42-55 (mean 49.3) - three operated for non-toxic nodular goiter and one for primary hyperparathyroidism. Each time the Non-RLN was seen on the right side. The other patients manifested recurrent character RLN. Moreover, interstitial course of RLN was found on the left side in one man. Non recurrent laryngeal nerve is a rare anatomical variation, occurring more frequently on the right side. Surgeon during surgery of the thyroid and parathyroid glands should be aware of its existence to avoid damage.

Effects of analgesia of the distal interphalangeal joint or palmar digital nerves on lameness caused by solar pain in horses.

PubMed

Schumacher, J; Steiger, R; Schumacher, J; de Graves, F; Schramme, M; Smith, R; Coker, M

2000-01-01

To determine if pain of the dorsal margin of the sole in horses can be attenuated by anesthesia of either the distal interphalangeal (DIP) joint or the palmar digital (PD) nerves. A unilateral forelimb lameness was induced by creating solar pain. Response to administration of local anesthetic or saline solution into the DIP joint and to administration of local anesthetic around the PD nerves was evaluated. Six horses. Lameness was induced by creating pressure on the dorsal margin of the sole by screwing set-screws into a nut welded to the inside of each branch of a shoe. Gaits were evaluated before and after application of set-screws and after a local anesthetic or saline solution was administered into the DIP joint and, in a second trial, after a local anesthetic was injected around the PD nerves. Gaits recorded on videotape were evaluated, and lameness scores were assigned to each gait. Lameness scores were high after application of set-screws and remained high after saline solution was administered into the DIP joint. Scores decreased significantly (P < or = .05) after a local anesthetic was administered into the DIP joint or around the PD nerves. Analgesia of the DIP joint or the PD nerves desensitizes at least a portion of the sole. Pain arising from the sole should not be excluded as a cause of lameness when lameness is attenuated by analgesia of the DIP joint or PD nerves.

Swimming behaviour and calcium incorporation into inner ear otoliths of fish after vestibular nerve transection

NASA Astrophysics Data System (ADS)

Edelmann, E.; Anken, R. H.; Rahmann, H.

2004-01-01

Previous investigations on neonate swordtail fish (Xiphophorus helleri) revealed that otolithic calcium incorporation (visualized using the calcium tracer alizarin complexone) and thus otolith growth had ceased after nerve transection, supporting a hypothesis according to which the gravity-dependent otolith growth is regulated neuronally. Subsequent investigations on larval cichlid fish (Oreochromis mossambicus) yielded contrasting results, repeatedly depending on the particular batch of cichlids investigated. Like most neonate swordtails, Type I cichlids revealed a stop of calcium incorporation after unilateral vestibular nerve transection. Their behaviour after transection was normal, and the otolithic calcium incorporation in controls of the same batch was symmetric. In Type II cichlids, however, vestibular nerve transection had no effect on otolithic calcium incorporation. They behaved kinetotically after transection (this kind of kinetosis was qualitatively similar to the swimming behaviour exhibited by larval cichlids during microgravity in the course of parabolic aircraft flights). The otolithic calcium incorporation in control animals was asymmetric. These results show that the effects of vestibular nerve transection as well as the efficacy of the mechanism, which regulates otolith growth/otolithic calcium incorporation, are - depending on the particular batch of animals - genetically predispositioned. In conclusion, the regulation of otolithic calcium incorporation is guided neuronally, in part via the vestibular nerve and, in part, via a further pathway, which remains to be addressed in the course of future investigations.

Peripheral axotomy of the rat mandibular trigeminal nerve leads to an increase in VIP and decrease of other primary afferent neuropeptides in the spinal trigeminal nucleus.

PubMed

Atkinson, M E; Shehab, S A

1986-12-01

In the vasoactive intestinal polypeptide (VIP)-rich lumbosacral spinal cord, VIP increases at the expense of other neuropeptides after primary sensory nerve axotomy. This study was undertaken to ascertain whether similar changes occur in peripherally axotomised cranial sensory nerves. VIP immunoreactivity increased in the terminal region of the mandibular nerve in the trigeminal nucleus caudalis following unilateral section of the sensory root of the mandibular trigeminal nerve at the foramen orale. Other primary afferent neuropeptides (substance P, cholecystokinin and somatostatin) were depleted and fluoride-resistant acid phosphatase activity was abolished in the same circumscribed areas of the nucleus caudalis. The rise in VIP and depletion of other markers began 4 days postoperatively and was maximal by 10 days, these levels remaining unchanged up to 1 year postoperatively. VIP-immunoreactive cell bodies were absent from trigeminal ganglia from the unoperated side but small and medium cells stained intensely in the ganglia of the operated side after axotomy. These observations indicate that increase of VIP in sensory nerve terminals is a general phenomenon occurring in both cranial and spinal sensory terminal areas. The intense VIP immunoreactivity in axotomised trigeminal ganglia suggests that the increased levels of VIP in the nucleus caudalis are of peripheral origin, indicating a change in expression of neuropeptides within primary afferent neurons following peripheral axotomy.

The influence of nerve section on the metabolism of polyamines in rat diaphragm muscle.

PubMed Central

Hopkins, D; Manchester, K L

1981-01-01

Concentrations of spermidine, spermine and putrescine have been measured in rat diaphragm muscle after unilateral nerve section. The concentration of putrescine increased approx. 10-fold 2 days after nerve section, that of spermidine about 3-fold by day 3, whereas an increase in the concentration of spermine was only observed after 7-10 days. It was not possible to show enhanced uptake of either exogenous putrescine or spermidine by the isolated tissue during the hypertrophy. Consistent with the accumulation of putrescine, activity of ornithine decarboxylase increased within 1 day of nerve section, was maximally elevated by the second day and then declined. Synthesis of spermidine from [14C]putrescine and either methionine or S-adenosylmethionine bt diaphragm cytosol rose within 1 day of nerve section, but by day 3 had returned to normal or below normal values. Activity of adenosylmethionine decarboxylase similarly increased within 1 day of nerve section, but by day 3 had declined to below normal values. Activity of methionine adenosyltransferase was elevated throughout the period studied. The concentration of S-adenosylmethionine was likewise enhanced during hypertrophy. Administration of methylglyoxal bis(guanylhydrazone) produced a marked increase in adenosylmethionine decarboxylase activity and a large increase in putrescine concentration, but did not prevent the rise in spermidine concentration produced by denervation. Possible regulatory mechanisms of polyamine metabolism consistent with the observations are discussed. PMID:7316998

Neuro-Ophthalmology at a Tertiary Eye Care Centre in India.

PubMed

Dhiman, Rebika; Singh, Digvijay; Gantayala, Shiva P; Ganesan, Vaitheeswaran L; Sharma, Pradeep; Saxena, Rohit

2017-11-09

Neuro-ophthalmology as a specialty is underdeveloped in India. The aim of our study was to determine the spectrum and profile of patients presenting to a tertiary eye care center with neuro-ophthalmic disorders. A retrospective hospital-based study was conducted, and records of all patients seen at the neuro-ophthalmology clinic of Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India, over a 1-year period were retrieved and evaluated. Of a total of 30,111 patients referred to various specialty clinics in a span of 1 year, 1597 (5%) were referred for neuro-ophthalmology evaluation. The mean patient age was 30.8 ± 19.5 years, with a male dominance (M:F = 2.02:1). Among these patients, optic nerve disorders were noted in 63.8% (n = 1,020), cranial nerve palsy in 7% (n = 114), cortical visual impairment in 6.5% (n = 105), and others (eye/optic nerve hypophasia, blepharospasm, and optic disc drusen) in 6% (n = 95). Among the patients with optic nerve disorders, optic neuropathy without disc edema/(traumatic optic neuropathy, hereditary, tumor-related, retrobulbar neuritis, toxic, and idiopathic) was noted in 42.8% (n = 685) and optic neuropathy with disc edema (ischemic optic neuropathy, papilledema, post-papilledema optic atrophy, papillitis, neuroretinitis, and inflammatory optic neuropathy) in 20.9% (n = 335). Sixteen percent of patients (n = 263) were incorrect referrals. The neuro-ophthalmic clinic constitutes a significant referral unit in a tertiary eye care center in India. Traumatic and ischemic optic neuropathies are the most common diagnoses. Neuro-ophthalmology requires further development as a subspecialty in India to better serve the nation's population.

REDUCED CHORIOCAPILLARIS FLOW IN EYES WITH TYPE 3 NEOVASCULARIZATION AND AGE-RELATED MACULAR DEGENERATION.

PubMed

Borrelli, Enrico; Souied, Eric H; Freund, K Bailey; Querques, Giuseppe; Miere, Alexandra; Gal-Or, Orly; Sacconi, Riccardo; Sadda, SriniVas R; Sarraf, David

2018-04-30

To study choriocapillaris (CC) flow in eyes with Type 3 neovascularization (NV) and age-related macular degeneration, using optical coherence tomography angiography analysis. In this multicenter, retrospective, observational study, we collected data from 21 patients with unilateral Type 3 NV and age-related macular degeneration, based on clinical examination, structural optical coherence tomography, and fluorescein angiography when available. An additional group of 20 nonneovascular age-related macular degeneration eyes with unilateral Type 1 or Type 2 NV due to age-related macular degeneration was included for comparison. En face optical coherence tomography angiography imaging (3 × 3 mm scans) with quantitative microvascular analysis of the CC was performed. Main outcome measures were: 1) the percent nonperfused choriocapillaris area; and 2) the average CC signal void size. We included 21 patients with unilateral Type 3 NV (15 female, 71.5%) and 20 patients with unilateral Type 1 or 2 NV (9 female, 45.0% P = 0.118). Mean ± SD age was 82.1 ± 7.4 years in the unilateral Type 3 patients and 78.3 ± 8.1 in unilateral Type 1/2 NV subjects (P = 0.392). The percent nonperfused choriocapillaris area was 56.3 ± 8.1% in eyes with Type 3 NV and 51.9 ± 4.3% in the fellow eyes (P = 0.016). The average signal void size was also increased in those eyes with Type 3 NV (939.9 ± 680.9 μm), compared with the fellow eyes (616.3 ± 304.2 μm, P = 0.039). The number of signal voids was reduced in the Type 3 NV eyes (604.5 ± 282.9 vs. 747.3 ± 195.8, P = 0.046). The subfoveal choroidal thickness was 135.9 ± 54.2 μm in eyes with Type 3 NV and 167.2 ± 65.4 μm in the fellow eyes (P = 0.003). In addition, the fellow eyes of patients with unilateral Type 3 NV displayed more significant CC flow abnormalities versus the fellow eyes with unilateral Type 1/2 NV (percent nonperfused choriocapillaris area = 51.9 ± 4.3% vs. 46.0 ± 2.1%, respectively, P < 0.0001; and average signal void size 616.3 ± 304.2 μm versus 351.4 ± 65.5 μm, respectively, P < 0.0001; and number of signal voids 747.3 ± 195.8 vs. 998.5 ± 147.3, respectively, P < 0.0001). Eyes with unilateral Type 3 NV illustrated increased CC nonperfusion versus fellow nonneovascular eyes. These results suggest that choroidal ischemia may play an important role in the development of Type 3 NV.

Multispectral photoacoustic imaging of nerves with a clinical ultrasound system

NASA Astrophysics Data System (ADS)

Mari, Jean Martial; West, Simeon; Beard, Paul C.; Desjardins, Adrien E.

2014-03-01

Accurate and efficient identification of nerves is of great importance during many ultrasound-guided clinical procedures, including nerve blocks and prostate biopsies. It can be challenging to visualise nerves with conventional ultrasound imaging, however. One of the challenges is that nerves can have very similar appearances to nearby structures such as tendons. Several recent studies have highlighted the potential of near-infrared optical spectroscopy for differentiating nerves and adjacent tissues, as this modality can be sensitive to optical absorption of lipids that are present in intra- and extra-neural adipose tissue and in the myelin sheaths. These studies were limited to point measurements, however. In this pilot study, a custom photoacoustic system with a clinical ultrasound imaging probe was used to acquire multi-spectral photoacoustic images of nerves and tendons from swine ex vivo, across the wavelength range of 1100 to 1300 nm. Photoacoustic images were processed and overlaid in colour onto co-registered conventional ultrasound images that were acquired with the same imaging probe. A pronounced optical absorption peak centred at 1210 nm was observed in the photoacoustic signals obtained from nerves, and it was absent in those obtained from tendons. This absorption peak, which is consistent with the presence of lipids, provides a novel image contrast mechanism to significantly enhance the visualization of nerves. In particular, image contrast for nerves was up to 5.5 times greater with photoacoustic imaging (0.82 +/- 0.15) than with conventional ultrasound imaging (0.148 +/- 0.002), with a maximum contrast of 0.95 +/- 0.02 obtained in photoacoustic mode. This pilot study demonstrates the potential of photoacoustic imaging to improve clinical outcomes in ultrasound-guided interventions in regional anaesthesia and interventional oncology.

Optic neuropathies--importance of spatial distribution of mitochondria as well as function.

PubMed

Yu Wai Man, C Y; Chinnery, P F; Griffiths, P G

2005-01-01

Optic neuropathies such as Leber's hereditary optic neuropathy, dominant optic atrophy and toxic amblyopia are an important cause of irreversible visual failure. Although they are associated with a defect of mitochondrial energy production, their pathogenesis is poorly understood. A common feature to all these disorders is relatively selective degeneration of the papillomacular bundle of retinal ganglion cells resulting central or caecocentral visual field defects. The striking similarity in the pattern of clinical involvement seen with these disparate disorders suggests a common pathway in their aetiology. The existing hypothesis that the optic nerve head has higher energy demands than other tissues making it uniquely dependent on oxidative phosporylation is not satisfactory. First, other ocular tissues such as photoreceptors, which are more dependent on oxidative phosporylation are not affected. Second, other mitochondrial disorders, which have a greater impact on mitochondrial energy function, do not affect the optic nerve. The optic nerve head has certain unique ultra structural features. Ganglion cell axons exit the eye through a perforated collagen plate, the lamina cribrosa. There is a sharp discontinuity in the density of mitochondria at the optic nerve head, with a very high concentration in the prelaminar nerve fibre layer and low concentration behind the lamina. This has previously been attributed to a mechanical hold up of axoplasmic flow, which has itself been proposed as a factor in the pathogenesis of a number of optic neuropathies. More recent evidence shows that mitochondrial distribution reflects the different energy requirements of the unmyelinated prelaminar axons in comparison to the myelinated retrolaminar axons. The heterogeous distribution of mitochondria is actively maintained to support conduction through the optic nerve head. We propose that factors that disrupt the heterogeneous distribution of mitochondria can result in ganglion cell death. Evidence for this comes from studies of cultured cells with the dominant optic atrophy mutation in which mitochondrial distribution is altered and from some forms of hereditary spastic paraparesis which are associated with optic atrophy. The responsible mutations do not affect ATP production until late in the disease but do affect mitochondrial arrangement, again showing that mitochondrial distribution as well as energy production by individual mitochondria may be important in the pathogenesis of ganglion cell death. Greater understanding of the factors localising mitochondria within the ganglion cell axon in particular the interaction with cytoskeleton is required to formulate new treatments. Boosting energy production alone may not be an effective treatment.

Non-invasive detection of animal nerve impulses with an atomic magnetometer operating near quantum limited sensitivity

PubMed Central

Jensen, Kasper; Budvytyte, Rima; Thomas, Rodrigo A.; Wang, Tian; Fuchs, Annette M.; Balabas, Mikhail V.; Vasilakis, Georgios; Mosgaard, Lars D.; Stærkind, Hans C.; Müller, Jörg H.; Heimburg, Thomas; Olesen, Søren-Peter; Polzik, Eugene S.

2016-01-01

Magnetic fields generated by human and animal organs, such as the heart, brain and nervous system carry information useful for biological and medical purposes. These magnetic fields are most commonly detected using cryogenically-cooled superconducting magnetometers. Here we present the first detection of action potentials from an animal nerve using an optical atomic magnetometer. Using an optimal design we are able to achieve the sensitivity dominated by the quantum shot noise of light and quantum projection noise of atomic spins. Such sensitivity allows us to measure the nerve impulse with a miniature room-temperature sensor which is a critical advantage for biomedical applications. Positioning the sensor at a distance of a few millimeters from the nerve, corresponding to the distance between the skin and nerves in biological studies, we detect the magnetic field generated by an action potential of a frog sciatic nerve. From the magnetic field measurements we determine the activity of the nerve and the temporal shape of the nerve impulse. This work opens new ways towards implementing optical magnetometers as practical devices for medical diagnostics. PMID:27417378

Non-invasive detection of animal nerve impulses with an atomic magnetometer operating near quantum limited sensitivity

NASA Astrophysics Data System (ADS)

Jensen, Kasper; Budvytyte, Rima; Thomas, Rodrigo A.; Wang, Tian; Fuchs, Annette M.; Balabas, Mikhail V.; Vasilakis, Georgios; Mosgaard, Lars D.; Stærkind, Hans C.; Müller, Jörg H.; Heimburg, Thomas; Olesen, Søren-Peter; Polzik, Eugene S.

2016-07-01

Magnetic fields generated by human and animal organs, such as the heart, brain and nervous system carry information useful for biological and medical purposes. These magnetic fields are most commonly detected using cryogenically-cooled superconducting magnetometers. Here we present the first detection of action potentials from an animal nerve using an optical atomic magnetometer. Using an optimal design we are able to achieve the sensitivity dominated by the quantum shot noise of light and quantum projection noise of atomic spins. Such sensitivity allows us to measure the nerve impulse with a miniature room-temperature sensor which is a critical advantage for biomedical applications. Positioning the sensor at a distance of a few millimeters from the nerve, corresponding to the distance between the skin and nerves in biological studies, we detect the magnetic field generated by an action potential of a frog sciatic nerve. From the magnetic field measurements we determine the activity of the nerve and the temporal shape of the nerve impulse. This work opens new ways towards implementing optical magnetometers as practical devices for medical diagnostics.

Bilateral Optic Disc Drusen Mimicking Papilledema

PubMed Central

Cingü, Abdullah Kürşat; Ari, Şeyhmus; Çinar, Yasin; Çaça, İhsan

2012-01-01

Background Optic disc drusen, which are calcified deposits that form anterior to the lamina cribrosa in the optic nerve, may mimic papilledema. Case Report We report herein three cases referred to us with suspicion of disc swelling and papilledema. Following ophthalmologic evaluation with B-scan ultrasound, red-free fundus photography, and computed tomography, the diagnosis of papilledema was excluded in all cases and optic disc drusen was diagnosed. Conclusions Clinical suspicion of optic disc drusen in cases presenting with swelling of the optic nerve head is important in order to avoid unnecessary interventions and anxiety. The reported cases highlight the commonly encountered clinical presentations and the practical aspects of diagnosis and management of optic disc drusen. PMID:22787500

Optical signature of nerve tissue-Exploratory ex vivo study comparing optical, histological, and molecular characteristics of different adipose and nerve tissues.

PubMed

Balthasar, Andrea J R; Bydlon, Torre M; Ippel, Hans; van der Voort, Marjolein; Hendriks, Benno H W; Lucassen, Gerald W; van Geffen, Geert-Jan; van Kleef, Maarten; van Dijk, Paul; Lataster, Arno

2018-05-14

During several anesthesiological procedures, needles are inserted through the skin of a patient to target nerves. In most cases, the needle traverses several tissues-skin, subcutaneous adipose tissue, muscles, nerves, and blood vessels-to reach the target nerve. A clear identification of the target nerve can improve the success of the nerve block and reduce the rate of complications. This may be accomplished with diffuse reflectance spectroscopy (DRS) which can provide a quantitative measure of the tissue composition. The goal of the current study was to further explore the morphological, biological, chemical, and optical characteristics of the tissues encountered during needle insertion to improve future DRS classification algorithms. To compare characteristics of nerve tissue (sciatic nerve) and adipose tissues, the following techniques were used: histology, DRS, absorption spectrophotometry, high-resolution magic-angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy, and solution 2D 13 C- 1 H heteronuclear single-quantum coherence spectroscopy. Tissues from five human freshly frozen cadavers were examined. Histology clearly highlights a higher density of cellular nuclei, collagen, and cytoplasm in fascicular nerve tissue (IFAS). IFAS showed lower absorption of light around 1200 nm and 1750 nm, higher absorption around 1500 nm and 2000 nm, and a shift in the peak observed around 1000 nm. DRS measurements showed a higher water percentage and collagen concentration in IFAS and a lower fat percentage compared to all other tissues. The scattering parameter (b) was highest in IFAS. The HR-MAS NMR data showed three extra chemical peak shifts in IFAS tissue. Collagen, water, and cellular nuclei concentration are clearly different between nerve fascicular tissue and other adipose tissue and explain some of the differences observed in the optical absorption, DRS, and HR-NMR spectra of these tissues. Some differences observed between fascicular nerve tissue and adipose tissues cannot yet be explained but may be helpful in improving the discriminatory capabilities of DRS in anesthesiology procedures. Lasers Surg. Med. 9999:1-13, 2018. © 2018 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc. © 2018 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.

Intravitreally transplanted dental pulp stem cells promote neuroprotection and axon regeneration of retinal ganglion cells after optic nerve injury.

PubMed

Mead, Ben; Logan, Ann; Berry, Martin; Leadbeater, Wendy; Scheven, Ben A

2013-11-15

To investigate the potential therapeutic benefit of intravitreally implanted dental pulp stem cells (DPSCs) on axotomized adult rat retinal ganglion cells (RGCs) using in vitro and in vivo neural injury models. Conditioned media collected from cultured rat DPSCs and bone marrow-derived mesenchymal stem cells (BMSCs) were assayed for nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3) secretion using ELISA. DPSCs or BMSCs were cocultured with retinal cells, with or without Fc-TrK inhibitors, in a Transwell system, and the number of surviving βIII-tubulin⁺ retinal cells and length/number of βIII-tubulin⁺ neurites were quantified. For the in vivo study, DPSCs or BMSCs were transplanted into the vitreous body of the eye after a surgically induced optic nerve crush injury. At 7, 14, and 21 days postlesion (dpl), optical coherence tomography (OCT) was used to measure the retinal nerve fiber layer thickness as a measure of axonal atrophy. At 21 dpl, numbers of Brn-3a⁺ RGCs in parasagittal retinal sections and growth-associated protein-43⁺ axons in longitudinal optic nerve sections were quantified as measures of RGC survival and axon regeneration, respectively. Both DPSCs and BMSCs secreted NGF, BDNF, and NT-3, with DPSCs secreting significantly higher titers of NGF and BDNF than BMSCs. DPSCs, and to a lesser extent BMSCs, promoted statistically significant survival and neuritogenesis/axogenesis of βIII-tubulin⁺ retinal cells in vitro and in vivo where the effects were abolished after TrK receptor blockade. Intravitreal transplants of DPSCs promoted significant neurotrophin-mediated RGC survival and axon regeneration after optic nerve injury.

ImagePAD, a novel counting application for the Apple iPad, used to quantify axons in the mouse optic nerve.

PubMed

Templeton, Justin P; Struebing, Felix L; Lemmon, Andrew; Geisert, Eldon E

2014-11-01

The present article introduces a new and easy to use counting application for the Apple iPad. The application "ImagePAD" takes advantage of the advanced user interface features offered by the Apple iOS platform, simplifying the rather tedious task of quantifying features in anatomical studies. For example, the image under analysis can be easily panned and zoomed using iOS-supported multi-touch gestures without losing the spatial context of the counting task, which is extremely important for ensuring count accuracy. This application allows one to quantify up to 5 different types of objects in a single field and output the data in a tab-delimited format for subsequent analysis. We describe two examples of the use of the application: quantifying axons in the optic nerve of the C57BL/6J mouse and determining the percentage of cells labeled with NeuN or ChAT in the retinal ganglion cell layer. For the optic nerve, contiguous images at 60× magnification were taken and transferred onto an Apple iPad. Axons were counted by tapping on the touch-sensitive screen using ImagePAD. Nine optic nerves were sampled and the number of axons in the nerves ranged from 38,872 axons to 50,196 axons with an average of 44,846 axons per nerve (SD = 3980 axons). Copyright © 2014 Elsevier Ltd. All rights reserved.

Scanning laser topography and scanning laser polarimetry: comparing both imaging methods at same distances from the optic nerve head.

PubMed

Kremmer, Stephan; Keienburg, Marcus; Anastassiou, Gerasimos; Schallenberg, Maurice; Steuhl, Klaus-Peter; Selbach, J Michael

2012-01-01

To compare the performance of scanning laser topography (SLT) and scanning laser polarimetry (SLP) on the rim of the optic nerve head and its surrounding area and thereby to evaluate whether these imaging technologies are influenced by other factors beyond the thickness of the retinal nerve fiber layer (RNFL). A total of 154 eyes from 5 different groups were examined: young healthy subjects (YNorm), old healthy subjects (ONorm), patients with normal tension glaucoma (NTG), patients with open-angle glaucoma and early glaucomatous damage (OAGE) and patients with open-angle glaucoma and advanced glaucomatous damage (OAGA). SLT and SLP measurements were taken. Four concentric circles were superimposed on each of the images: the first one measuring at the rim of the optic nerve head (1.0 ONHD), the next measuring at 1.25 optic nerve head diameters (ONHD), at 1.5 ONHD and at 1.75 ONHD. The aligned images were analyzed using GDx/NFA software. Both methods showed peaks of RNFL thickness in the superior and inferior segments of the ONH. The maximum thickness, registered by the SLT device was at the ONH rim where the SLP device tended to measure the lowest values. SLT measurements at the ONH were influenced by other tissues besides the RNFL like blood vessels and glial tissues. SLT and SLP were most strongly correlated at distances of 1.25 and 1.5 ONHD. While both imaging technologies are valuable tools in detecting glaucoma, measurements at the ONH rim should be interpreted critically since both methods might provide misleading results. For the assessment of the retinal nerve fiber layer we would like to recommend for both imaging technologies, SLT and SLP, measurements in 1.25 and 1.5 ONHD distance of the rim of the optic nerve head.

Analysis of macular and nerve fiber layer thickness in multiple sclerosis patients according to severity level and optic neuritis episodes.

PubMed

Soler García, A; Padilla Parrado, F; Figueroa-Ortiz, L C; González Gómez, A; García-Ben, A; García-Ben, E; García-Campos, J M

2016-01-01

Quantitative assessment of macular and nerve fibre layer thickness in multiple sclerosis patients with regard to expanded disability status scale (EDSS) and presence or absence of previous optic neuritis episodes. We recruited 62 patients with multiple sclerosis (53 relapsing-remitting and 9 secondary progressive) and 12 disease-free controls. All patients underwent an ophthalmological examination, including quantitative analysis of the nerve fibre layer and macular thickness using optical coherence tomography. Patients were classified according to EDSS as A (lower than 1.5), B (between 1.5 and 3.5), and C (above 3.5). Mean nerve fibre layer thickness in control, A, B, and C groups was 103.35±12.62, 99.04±14.35, 93.59±15.41, and 87.36±18.75μm respectively, with statistically significant differences (P<.05). In patients with no history of optic neuritis, history of episodes in the last 3 to 6 months, or history longer than 6 months, mean nerve fibre layer thickness was 99.25±13.71, 93.92±13.30 and 80.07±15.91μm respectively; differences were significant (P<.05). Mean macular thickness in control, A, B, and C groups was 220.01±12.07, 217.78±20.02, 217.68±20.77, and 219.04±24.26μm respectively. Differences were not statistically significant. The mean retinal nerve fibre layer thickness in multiple sclerosis patients is related to the EDSS level. Patients with previous optic neuritis episodes have a thinner retinal nerve fibre layer than patients with no history of these episodes. Mean macular thickness is not correlated to EDSS level. Copyright © 2014 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Finite Element Modeling of the Posterior Eye in Microgravity

NASA Technical Reports Server (NTRS)

Feola, Andrew; Raykin, Julia; Mulugeta, Lealem; Gleason, Rudolph; Myers, Jerry G.; Nelson, Emily S.; Samuels, Brian; Ethier, C. Ross

2015-01-01

Microgravity experienced during spaceflight affects astronauts in various ways, including weakened muscles and loss of bone density. Recently, visual impairment and intracranial pressure (VIIP) syndrome has become a major concern for space missions lasting longer than 30 days. Astronauts suffering from VIIP syndrome have changes in ocular anatomical and visual impairment that persist after returning to earth. It is hypothesized that a cephalad fluid shift in microgravity may increase the intracranial pressure (ICP), which leads to an altered biomechanical environment of the posterior globe and optic nerve sheath (ONS).Currently, there is a lack of knowledge of how elevated ICP may lead to vision impairment and connective tissue changes in VIIP. Our goal was to develop a finite element model to simulate the acute effects of elevated ICP on the posterior eye and optic nerve sheath. We used a finite element (FE) analysis approach to understand the response of the lamina cribrosa and optic nerve to the elevations in ICP thought to occur in microgravity and to identify which tissue components have the greatest impact on strain experienced by optic nerve head tissues.

Transbulbar B-Mode Sonography in Multiple Sclerosis: Clinical and Biological Relevance.

PubMed

De Masi, Roberto; Orlando, Stefania; Conte, Aldo; Pasca, Sergio; Scarpello, Rocco; Spagnolo, Pantaleo; Muscella, Antonella; De Donno, Antonella

2016-12-01

Optic nerve sheath diameter quantification by transbulbar B-mode sonography is a recently validated technique, but its clinical relevance in relapse-free multiple sclerosis patients remains unexplored. In an open-label, comparative, cross-sectional study, we aimed to assess possible differences between patients and healthy controls in terms of optic nerve sheath diameter and its correlation with clinical/paraclinical parameters in this disease. Sixty unselected relapse-free patients and 35 matched healthy controls underwent transbulbar B-mode sonography. Patients underwent routine neurologic examination, brain magnetic resonance imaging and visual evoked potential tests. The mean optic nerve sheath diameter 3 and 5 mm from the eyeball was 22-25% lower in patients than controls and correlated with the Expanded Disability Status Scale (r = -0.34, p = 0.048, and r = -0.32, p = 0.042, respectively). We suggest that optic nerve sheath diameter quantified by transbulbar B-mode sonography should be included in routine assessment of the disease as an extension of the neurologic examination. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

[Traumatic lesion of the optic nerve head by flying fish: a case report].

PubMed

Martin, M; Orgül, S; Robertson, A; Flammer, J

2004-05-01

Traumatic lesion to the optic nerve often leads to severe and persistent functional loss. A male patient was transferred to our hospital from the University Eye Clinic of Guadeloupe 5 days after ocular injury caused by a flying fish. Visual function was light perception. The anterior part of the eye and retina were unremarkable. A computer tomography disclosed a fracture of the sphenoid sinus, with a little bone fragment (DD: foreign body) located close to the optic nerve. Therapy had been started with Aminopenicillin combined with clavulan acid (Augmentin) i. v., 500 ml methylprednisolone (Solumedrol) i. v., lysine-acetyl salicylate (Aspegic) and topical application of dexamethasone combined with neomycin/polymyxin B (Maxitrol). We continued this therapy and intensified it by adding nimodipine (Nimotop) 30 1-1-1 and acetazolamide retard (Diamox sustet) 1-0-1. Unfortunately visual function did not recover under therapy. Traumatic lesions of the optic nerve head, especially when due to axial or tangential forces, can lead to severe and irreversible functional loss. Severe traumatic lesions, even bone fractures induced by flying fish are not a seldom encounter in the Caribbean Sea.

Assessment of rat optic nerve damage due to microbeam radiation therapy in the treatment of glioblastomas.

PubMed

Mohamed, A; Worobec, S; Schultke, E

2008-01-01

Glioblastomas are the most common and aggressive subtype of human primary brain tumors. Due to their uncontrolled cellular proliferation, intense invasion, and lack of apoptosis, they are extremely difficult to treat. Currently, different approaches such as surgery, chemotherapy and radiation therapy have been employed as possible treatments however thus far; these treatments are not curative. Currently, microbeam radiation therapy (MRT) is being trialed in animal models of malignant brain tumors (rats) to aid in treatment. Some of the protocols tested have been shown to significantly increase survival rates. However, due to the high x-ray doses uses in MRT, the surrounding tissue of the targeted Glioblastomas may be irreversibly damaged. In previous studies, lens damage and clouding of the cornea have been observed in microbeam exposed eyes. However, to date no studies have assessed optic nerve damage. Therefore, this study examines the potential rat optic nerve damage following exposure to microbeam radiation therapy in the treatment of Glioblastomas. Although there appears to be no significant damage to the optic nerve, slight inflammation was observed within the extra ocular muscle.

Hypothesis that vagal reinervation of diaphragm could sensitise it to electrical stimulation.

PubMed

Pavlovic, Dragan; Wendt, Michael

2003-03-01

The hypothesis proposed is that restoration of functional capacity of denervated diaphragm may be achieved by reinervating it with vagus nerve. Following trauma, carcinomatose infiltration, and/or large thoracic surgery and neck surgery, phrenic nerve is frequently injured. Reinervation even in the most favourable conditions would not follow and diaphragm would rest permanently denervated and paralysed. This results in unilateral or bilateral paralysis of diaphragm. In principle, intermittent electrical stimulation of the phrenic nerve or diaphragm could elicit regular diaphragm contractions and maintain satisfactory respiration. While this technique could be used in upper motor neurone injury, in lower motor neurone injury and denervated diaphragm, that imposes too high electrical resistance, direct diaphragm pacing is practically impossible. In these cases, long term artificial ventilation is often necessary. Nevertheless, those patients are at high risk to suffer from atelectasis and respiratory infections. We project a hypothesis that reinervation of denervated diaphragm by vagus nerve could re-establishes its sensitivity to intramuscular electrical stimulation and may allow stimulation of the diaphragm by implanted pace-maker electrodes. An appropriate electrical stimulation might then be possible and diaphragm pacing could replace prolonged artificial ventilation in those patients. Restoration of functional capacity of denervated diaphragm could open a perspective for long term diaphragm pacing in patients with irreversible phrenic nerve injury and diaphragm paralysis.

A System for Studying Facial Nerve Function in Rats through Simultaneous Bilateral Monitoring of Eyelid and Whisker Movements

PubMed Central

Heaton, James T.; Kowaleski, Jeffrey M.; Bermejo, Roberto; Zeigler, H. Philip; Ahlgren, David J.; Hadlock, Tessa A.

2008-01-01

The occurrence of inappropriate co-contraction of facially innervated muscles in humans (synkinesis) is a common sequela of facial nerve injury and recovery. We have developed a system for studying facial nerve function and synkinesis in restrained rats using non-contact opto-electronic techniques that enable simultaneous bilateral monitoring of eyelid and whisker movements. Whisking is monitored in high spatio-temporal resolution using laser micrometers, and eyelid movements are detected using infrared diode and phototransistor pairs that respond to the increased reflection when the eyelids cover the cornea. To validate the system, eight rats were tested with multiple five-minute sessions that included corneal air puffs to elicit blink and scented air flows to elicit robust whisking. Four rats then received unilateral facial nerve section and were tested at weeks 3–6. Whisking and eye blink behavior occurred both spontaneously and under stimulus control, with no detectable difference from published whisking data. Proximal facial nerve section caused an immediate ipsilateral loss of whisking and eye blink response, but some ocular closures emerged due to retractor bulbi muscle function. The independence observed between whisker and eyelid control indicates that this system may provide a powerful tool for identifying abnormal co-activation of facial zones resulting from aberrant axonal regeneration. PMID:18442856

Layer 5 Pyramidal Neurons' Dendritic Remodeling and Increased Microglial Density in Primary Motor Cortex in a Murine Model of Facial Paralysis

PubMed Central

Urrego, Diana; Troncoso, Julieta; Múnera, Alejandro

2015-01-01

This work was aimed at characterizing structural changes in primary motor cortex layer 5 pyramidal neurons and their relationship with microglial density induced by facial nerve lesion using a murine facial paralysis model. Adult transgenic mice, expressing green fluorescent protein in microglia and yellow fluorescent protein in projecting neurons, were submitted to either unilateral section of the facial nerve or sham surgery. Injured animals were sacrificed either 1 or 3weeks after surgery. Two-photon excitation microscopy was then used for evaluating both layer 5 pyramidal neurons and microglia in vibrissal primary motor cortex (vM1). It was found that facial nerve lesion induced long-lasting changes in the dendritic morphology of vM1 layer 5 pyramidal neurons and in their surrounding microglia. Dendritic arborization of the pyramidal cells underwent overall shrinkage. Apical dendrites suffered transient shortening while basal dendrites displayed sustained shortening. Moreover, dendrites suffered transient spine pruning. Significantly higher microglial cell density was found surrounding vM1 layer 5 pyramidal neurons after facial nerve lesion with morphological bias towards the activated phenotype. These results suggest that facial nerve lesions elicit active dendrite remodeling due to pyramidal neuron and microglia interaction, which could be the pathophysiological underpinning of some neuropathic motor sequelae in humans. PMID:26064916

Optic nerve regeneration in the mouse is a complex trait modulated by genetic background

PubMed Central

Wang, Jiaxing; Li, Ying; King, Rebecca; Struebing, Felix L.

2018-01-01

Purpose The present study is designed to identify the influences of genetic background on optic nerve regeneration using the two parental strains (C57BL/6J and DBA/2J) and seven BXD recombinant inbred mouse strains. Methods To study regeneration in the optic nerve, Pten was knocked down in the retinal ganglion cells using adenoassociated virus (AAV) delivery of shRNA, and a mild inflammatory response was induced with an intravitreal injection of zymosan with CPT-cAMP. The axons of the retinal ganglion cells were damaged by optic nerve crush (ONC). Following a 12-day survival period, regenerating axons were labeled by cholera toxin B, and 2 days later, the regenerating axons within the optic nerve were examined. The number of axons at 0.5 mm and 1 mm from the crush site were counted. In addition, we measured the distance that five axons had grown down the nerve and the longest distance a single axon reached. Results The analysis revealed a considerable amount of differential axonal regeneration across the seven BXD strains and the parental strains. There was a statistically significant difference (p=0.014 Mann–Whitney U test) in the regenerative capacity in the number of axons reaching 0.5 mm from a low of 236.1±24.4 axons in the BXD102 mice to a high of 759.8±79.2 axons in the BXD29 mice. There were also statistically significant differences (p=0.014 Mann–Whitney U test) in the distance axons traveled. Looking at a minimum of five axons, the shortest distance was 787.2±46.5 µm in the BXD102 mice, and the maximum distance was 2025.5±223.3 µm in the BXD29 mice. Conclusions Differences in genetic background can have a profound effect on axonal regeneration causing a threefold increase in the number of regenerating axons at 0.5 mm from the crush site and a 2.5-fold increase in the distance traveled by at least five axons in the damaged optic nerve. PMID:29463955

Disrupting vagal feedback affects birdsong motor control.

PubMed

Méndez, Jorge M; Dall'asén, Analía G; Goller, Franz

2010-12-15

Coordination of different motor systems for sound production involves the use of feedback mechanisms. Song production in oscines is a well-established animal model for studying learned vocal behavior. Whereas the online use of auditory feedback has been studied in the songbird model, very little is known about the role of other feedback mechanisms. Auditory feedback is required for the maintenance of stereotyped adult song. In addition, the use of somatosensory feedback to maintain pressure during song has been demonstrated with experimentally induced fluctuations in air sac pressure. Feedback information mediating this response is thought to be routed to the central nervous system via afferent fibers of the vagus nerve. Here, we tested the effects of unilateral vagotomy on the peripheral motor patterns of song production and the acoustic features. Unilateral vagotomy caused a variety of disruptions and alterations to the respiratory pattern of song, some of which affected the acoustic structure of vocalizations. These changes were most pronounced a few days after nerve resection and varied between individuals. In the most extreme cases, the motor gestures of respiration were so severely disrupted that individual song syllables or the song motif were atypically terminated. Acoustic changes also suggest altered use of the two sound generators and upper vocal tract filtering, indicating that the disruption of vagal feedback caused changes to the motor program of all motor systems involved in song production and modification. This evidence for the use of vagal feedback by the song system with disruption of song during the first days after nerve cut provides a contrast to the longer-term effects of auditory feedback disruption. It suggests a significant role for somatosensory feedback that differs from that of auditory feedback.

Disrupting vagal feedback affects birdsong motor control

PubMed Central

Méndez, Jorge M.; Dall'Asén, Analía G.; Goller, Franz

2010-01-01

Coordination of different motor systems for sound production involves the use of feedback mechanisms. Song production in oscines is a well-established animal model for studying learned vocal behavior. Whereas the online use of auditory feedback has been studied in the songbird model, very little is known about the role of other feedback mechanisms. Auditory feedback is required for the maintenance of stereotyped adult song. In addition, the use of somatosensory feedback to maintain pressure during song has been demonstrated with experimentally induced fluctuations in air sac pressure. Feedback information mediating this response is thought to be routed to the central nervous system via afferent fibers of the vagus nerve. Here, we tested the effects of unilateral vagotomy on the peripheral motor patterns of song production and the acoustic features. Unilateral vagotomy caused a variety of disruptions and alterations to the respiratory pattern of song, some of which affected the acoustic structure of vocalizations. These changes were most pronounced a few days after nerve resection and varied between individuals. In the most extreme cases, the motor gestures of respiration were so severely disrupted that individual song syllables or the song motif were atypically terminated. Acoustic changes also suggest altered use of the two sound generators and upper vocal tract filtering, indicating that the disruption of vagal feedback caused changes to the motor program of all motor systems involved in song production and modification. This evidence for the use of vagal feedback by the song system with disruption of song during the first days after nerve cut provides a contrast to the longer-term effects of auditory feedback disruption. It suggests a significant role for somatosensory feedback that differs from that of auditory feedback. PMID:21113000

Distribution of retroperitoneal lymph node metastases in patients with non-seminomatous testicular cancer in clinical stage I.

PubMed

Fosså, S D; Ous, S; Stenwig, A E; Lien, H H; Aass, N; Kaalhus, O

1990-01-01

118 Patients with non-seminomatous testicular cancer (NSTC) in clinical stage I (CSI = no metastases by clinical, radiological and biochemical evaluation) underwent retroperitoneal lymph node dissection (RLND). The operation was done unilaterally (95 patients) in peroperatively tumor-free patients or in those with limited metastatic growth. In 23 patients with more extensive metastases, bilateral RLND was performed. Metastatic lymph nodes were found in 36 patients, and these patients received 3-4 cycles of a cisplatin-based combination chemotherapy. If no metastases were detected the patients had no further treatment. The 5-year disease-free survival rate was 100%. 8 of 82 patients without detected metastases in the operation specimen relapsed (all outside the retroperitoneal space), but were cured by salvage chemotherapy. Solitary metastases were found in 11 patients, whereas 25 patients had more than 1 metastatic lymph node. The size of the largest metastasis ranged from 0.3 to 40 mm. Metastases from right-sided tumors were detected at all levels of the lumbar region, predominantly to the right of the inferior vena cava and/or within the interaortocaval space. Left-sided tumors metastasized to the upper two thirds of the lumbar space, only rarely crossing the midline. This anatomical distribution of metastatic lymph nodes indicates that the presacral sympathetic nerve plexus and the sympathetic nerve fibers around the aortic bifurcation can be spared from extensive resection in the majority of patients with NSTC in CSI. Unilateral RLND or other nerve-sparing techniques are thus possible, preserving antegrade ejaculation in greater than 80% of the patients. This RLND represents a reasonable alternative to the 'surveillance' policy in NSTC.

Retinal ganglion cell damage in an experimental rodent model of blast-mediated traumatic brain injury.

PubMed

Mohan, Kabhilan; Kecova, Helga; Hernandez-Merino, Elena; Kardon, Randy H; Harper, Matthew M

2013-05-15

To evaluate retina and optic nerve damage following experimental blast injury. Healthy adult mice were exposed to an overpressure blast wave using a custom-built blast chamber. The effects of blast exposure on retina and optic nerve function and structure were evaluated using the pattern electroretinogram (pERG), spectral domain optical coherence tomography (OCT), and the chromatic pupil light reflex. Assessment of the pupil response to light demonstrated decreased maximum pupil constriction diameter in blast-injured mice using red light or blue light stimuli 24 hours after injury compared with baseline in the eye exposed to direct blast injury. A decrease in the pupil light reflex was not observed chronically following blast exposure. We observed a biphasic pERG decrease with the acute injury recovering by 24 hours postblast and the chronic injury appearing at 4 months postblast injury. Furthermore, at 3 months following injury, a significant decrease in the retinal nerve fiber layer was observed using OCT compared with controls. Histologic analysis of the retina and optic nerve revealed punctate regions of reduced cellularity in the ganglion cell layer and damage to optic nerves. Additionally, a significant upregulation of proteins associated with oxidative stress was observed acutely following blast exposure compared with control mice. Our study demonstrates that decrements in retinal ganglion cell responses can be detected after blast injury using noninvasive functional and structural tests. These objective responses may serve as surrogate tests for higher CNS functions following traumatic brain injury that are difficult to quantify.

Twelve-hour reproducibility of retinal and optic nerve blood flow parameters in healthy individuals.

PubMed

Luksch, Alexandra; Lasta, Michael; Polak, Kaija; Fuchsjäger-Mayrl, Gabriele; Polska, Elzbieta; Garhöfer, Gerhard; Schmetterer, Leopold

2009-11-01

The aim of the present study was to investigate the reproducibility and potential diurnal variation of optic nerve head and retinal blood flow parameters in healthy individuals over a period of 12 hr. We measured optic nerve head and retinal blood flow parameters in 16 healthy male non-smoking individuals at five time-points during the day (08:00, 11:00, 14:00, 17:00 and 20:00 hr). Outcome parameters were perimacular white blood cell flux (as assessed with the blue field entoptic technique), blood velocities in retinal veins (as assessed with bi-directional laser Doppler velocimetry), retinal arterial and venous diameters (as assessed with the retinal vessel analyser), optic nerve head blood flow, volume and velocity (as assessed with single point and scanning laser Doppler flowmetry) and blood velocities in the central retinal artery (as assessed with colour Doppler imaging). The coefficient of variation and the maximum change from baseline in an individual were calculated for each outcome parameter. No diurnal variation in optic nerve head or retinal blood flow was observed with any of the techniques employed. Coefficients of variation were between 1.6% and 18.5% for all outcome parameters. The maximum change from baseline in an individual was much higher, ranging from 3.7% to 78.2%. Our data indicate that in healthy individuals the selected techniques provide adequate reproducibility to be used in clinical studies. However, in patients with eye diseases and reduced vision the reproducibility may be considerably worse.

Augmented superior rectus transposition procedure in Duane retraction syndrome compared with sixth nerve palsy.

PubMed

Akbari, Mohammadreza; Shomali, Setareh; Mirmohammadsadeghi, Arash; Fard, Masoud Aghsaei

2018-05-01

Superior rectus transposition (SRT) with medial rectus recession has been used for the treatment of sixth nerve palsy and esotropic Duane retraction syndrome (DRS). The purpose of this study was to compare the results of augmented SRT (with scleral fixation) without medial rectus recession in DRS and sixth nerve palsy. Patients with unilateral esotropic DRS (DRS group) and sixth nerve palsy were included in this prospective, comparative study and underwent SRT. Preoperative forced duction testing was negative or slightly positive in both groups. Prospective measurements were compared between the two groups. There were 11 patients in the DRS group and 11 patients in the sixth nerve palsy group. The mean preoperative esotropia decreased from 20.9 ± 6.0 prism diopter (PD) at far to 13.2 ± 5.8 PD in the DRS group (P = 0.003). The same measurement improved from 28.0 ± 8.5 PD to 8.4 ± 7.3 PD in the sixth nerve palsy group (P = 0.003). In the sixth nerve palsy group, the improvement in primary gaze esotropia and abnormal head posture was more than the DRS group (Both P < 0.001).The average dose effect for SRT was 7.8 ± 2.2 PD in the DRS group and 19.2 ± 4.6 PD in the sixth nerve palsy group. Although objective intorsion was significantly induced after SRT, subjective torsion was not significant after surgery in both groups. SRT appears to be more effective in improving primary gaze deviation and head posture in sixth nerve palsy compared with DRS. Subjective torsional and vertical diplopia were rare in both groups.

Value of 3D MR lumbosacral radiculography in the diagnosis of symptomatic chemical radiculitis.

PubMed

Byun, W M; Ahn, S H; Ahn, M-W

2012-03-01

Radiologic methods for the diagnosis of chemical radiculitis associated with anular tears in the lumbar spine have been rare. Provocative diskography is one of the methods for diagnosing diskogenic chemical radiculitis but is invasive. A reliable imaging method for replacing provocative diskography and diagnosing chemical radiculitis is required. Our aim was to investigate the value of 3D MR radiculography depicted by rendering imaging in the diagnosis of symptomatic chemical radiculopathy associated with anular tears. The study population consisted of 17 patients (age range, 32-88 years) with unilateral radiculopathy. Symptomatic chemical radiculopathy was confirmed with provocative CT diskography and/or provocative selective nerve root block for agreement of sides and levels. Through adhering to the principles of selective excitation (Proset imaging), we acquired 3D coronal FFE sequences with selective water excitation. Morphologic changes in the ipsilateral symptomatic nerve root caused by chemical radiculopathy were compared with those in the contralateral nerve root on 3D MR lumbosacral radiculography. Pain reproduction at the contrast-leak level during diskography (n = 4) and selective nerve root injection (n = 13) showed concordant pain in all patients. All patients with symptomatic chemical radiculopathy showed nerve root swelling in both ipsilateral levels and sides on 3D MR radiculography. The most common nerve root affected by the chemical radiculopathy was the L5 nerve root (n = 13), while the most common segment exhibiting nerve root swelling was the exit nerve root (n = 16). All patients with radicular leg pain caused by chemical radiculopathy showed nerve root swelling on 3D MR radiculography. We believe that in cases without mechanical nerve root compression caused by disk herniation or stenosis in the lumbar spine, nerve root swelling on 3D MR radiculography in patients with radiculopathy associated with an anular tear may be relevant in the diagnosis of symptomatic chemical radiculopathy.

Rat Whisker Movement after Facial Nerve Lesion: Evidence for Autonomic Contraction of Skeletal Muscle

PubMed Central

Heaton, James T.; Sheu, Shu-Hsien; Hohman, Marc H.; Knox, Christopher J.; Weinberg, Julie S.; Kleiss, Ingrid J.; Hadlock, Tessa A.

2014-01-01

Vibrissal whisking is often employed to track facial nerve regeneration in rats; however, we have observed similar degrees of whisking recovery after facial nerve transection with or without repair. We hypothesized that the source of non-facial nerve-mediated whisker movement after chronic denervation was from autonomic, cholinergic axons traveling within the infraorbital branch of the trigeminal nerve (ION). Rats underwent unilateral facial nerve transection with repair (N=7) or resection without repair (N=11). Post-operative whisking amplitude was measured weekly across 10 weeks, and during intraoperative stimulation of the ION and facial nerves at ≥18 weeks. Whisking was also measured after subsequent ION transection (N=6) or pharmacologic blocking of the autonomic ganglia using hexamethonium (N=3), and after snout cooling intended to elicit a vasodilation reflex (N=3). Whisking recovered more quickly and with greater amplitude in rats that underwent facial nerve repair compared to resection (P<0.05), but individual rats overlapped in whisking amplitude across both groups. In the resected rats, non-facial-nerve mediated whisking was elicited by electrical stimulation of the ION, temporarily diminished following hexamethonium injection, abolished by transection of the ION, and rapidly and significantly (P<0.05) increased by snout cooling. Moreover, fibrillation-related whisker movements decreased in all rats during the initial recovery period (indicative of reinnervation), but re-appeared in the resected rats after undergoing ION transection (indicative of motor denervation). Cholinergic, parasympathetic axons traveling within the ION innervate whisker pad vasculature, and immunohistochemistry for vasoactive intestinal peptide revealed these axons branching extensively over whisker pad muscles and contacting neuromuscular junctions after facial nerve resection. This study provides the first behavioral and anatomical evidence of spontaneous autonomic innervation of skeletal muscle after motor nerve lesion, which not only has implications for interpreting facial nerve reinnervation results, but also calls into question whether autonomic-mediated innervation of striated muscle occurs naturally in other forms of neuropathy. PMID:24480367

Rat whisker movement after facial nerve lesion: evidence for autonomic contraction of skeletal muscle.

PubMed

Heaton, James T; Sheu, Shu Hsien; Hohman, Marc H; Knox, Christopher J; Weinberg, Julie S; Kleiss, Ingrid J; Hadlock, Tessa A

2014-04-18

Vibrissal whisking is often employed to track facial nerve regeneration in rats; however, we have observed similar degrees of whisking recovery after facial nerve transection with or without repair. We hypothesized that the source of non-facial nerve-mediated whisker movement after chronic denervation was from autonomic, cholinergic axons traveling within the infraorbital branch of the trigeminal nerve (ION). Rats underwent unilateral facial nerve transection with repair (N=7) or resection without repair (N=11). Post-operative whisking amplitude was measured weekly across 10weeks, and during intraoperative stimulation of the ION and facial nerves at ⩾18weeks. Whisking was also measured after subsequent ION transection (N=6) or pharmacologic blocking of the autonomic ganglia using hexamethonium (N=3), and after snout cooling intended to elicit a vasodilation reflex (N=3). Whisking recovered more quickly and with greater amplitude in rats that underwent facial nerve repair compared to resection (P<0.05), but individual rats overlapped in whisking amplitude across both groups. In the resected rats, non-facial-nerve-mediated whisking was elicited by electrical stimulation of the ION, temporarily diminished following hexamethonium injection, abolished by transection of the ION, and rapidly and significantly (P<0.05) increased by snout cooling. Moreover, fibrillation-related whisker movements decreased in all rats during the initial recovery period (indicative of reinnervation), but re-appeared in the resected rats after undergoing ION transection (indicative of motor denervation). Cholinergic, parasympathetic axons traveling within the ION innervate whisker pad vasculature, and immunohistochemistry for vasoactive intestinal peptide revealed these axons branching extensively over whisker pad muscles and contacting neuromuscular junctions after facial nerve resection. This study provides the first behavioral and anatomical evidence of spontaneous autonomic innervation of skeletal muscle after motor nerve lesion, which not only has implications for interpreting facial nerve reinnervation results, but also calls into question whether autonomic-mediated innervation of striated muscle occurs naturally in other forms of neuropathy. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

GlyCAM1 negatively regulates monocyte entry into the optic nerve head and contributes to radiation-based protection in glaucoma.

PubMed

Williams, Pete A; Braine, Catherine E; Foxworth, Nicole E; Cochran, Kelly E; John, Simon W M

2017-04-26

We previously reported a profound long-term neuroprotection subsequent to a single radiation-therapy in the DBA/2J mouse model of glaucoma. This neuroprotection prevents entry of monocyte-like immune cells into the optic nerve head during glaucoma. Gene expression studies in radiation-treated mice implicated Glycam1 in this protection. Glycam1 encodes a proteoglycan ligand for L-selectin and is an excellent candidate to modulate immune cell entry into the eye. Here, we experimentally test the hypothesis that radiation-induced over-expression of Glycam1 is a key component of the neuroprotection. We generated a null allele of Glycam1 on a DBA/2J background. Gene and protein expression of Glycam1, monocyte entry into the optic nerve head, retinal ganglion cell death, and axon loss in the optic nerve were assessed. Radiation therapy potently inhibits monocyte entry into the optic nerve head and prevents retinal ganglion cell death and axon loss. DBA/2J mice carrying a null allele of Glycam1 show increased monocyte entry and increased retinal ganglion cell death and axon loss following radiation therapy, but the majority of optic nerves were still protected by radiation therapy. Although GlyCAM1 is an L-selectin ligand, its roles in immunity are not yet fully defined. The current study demonstrates a partial role for GlyCAM1 in radiation-mediated protection. Furthermore, our results clearly show that GlyCAM1 levels modulate immune cell entry from the vasculature into neural tissues. As Glycam1 deficiency has a more profound effect on cell entry than on neurodegeneration, further experiments are needed to precisely define the role of monocyte entry in DBA/2J glaucoma. Nevertheless, GlyCAM1's function as a negative regulator of extravasation may lead to novel therapeutic strategies for an array of common conditions involving inflammation.

Optic nerve head blood flow response to reduced ocular perfusion pressure by alteration of either the blood pressure or intraocular pressure.

PubMed

Wang, Lin; Cull, Grant A; Fortune, Brad

2015-04-01

To test the hypothesis that blood flow autoregulation in the optic nerve head has less reserve to maintain normal blood flow in the face of blood pressure-induced ocular perfusion pressure decrease than a similar magnitude intraocular pressure-induced ocular perfusion pressure decrease. Twelve normal non-human primates were anesthetized by continuous intravenous infusion of pentobarbital. Optic nerve blood flow was monitored by laser speckle flowgraphy. In the first group of animals (n = 6), the experimental eye intraocular pressure was maintained at 10 mmHg using a saline reservoir connected to the anterior chamber. The blood pressure was gradually reduced by a slow injection of pentobarbital. In the second group (n = 6), the intraocular pressure was slowly increased from 10 mmHg to 50 mmHg by raising the reservoir. In both experimental groups, optic nerve head blood flow was measured continuously. The blood pressure and intraocular pressure were simultaneously recorded in all experiments. The optic nerve head blood flow showed significant difference between the two groups (p = 0.021, repeat measures analysis of variance). It declined significantly more in the blood pressure group compared to the intraocular pressure group when the ocular perfusion pressure was reduced to 35 mmHg (p < 0.045) and below. There was also a significant interaction between blood flow changes and the ocular perfusion pressure treatment (p = 0.004, adjusted Greenhouse & Geisser univariate test), indicating the gradually enlarged blood flow difference between the two groups was due to the ocular perfusion pressure decrease. The results show that optic nerve head blood flow is more susceptible to an ocular perfusion pressure decrease induced by lowering the blood pressure compared with that induced by increasing the intraocular pressure. This blood flow autoregulation capacity vulnerability to low blood pressure may provide experimental evidence related to the hemodynamic pathophysiology in glaucoma.

Calf enlargement associated with neurologic disease: two uncommon cases.

PubMed

Harwood, S C; Honet, J C

1988-01-01

Muscle enlargement and hypertrophy are rare findings in neurogenic lesions. The two in combination have been reported in cases of peripheral nerve lesions, polyneuropathy, and poliomyelitis. True and pseudo muscle hypertrophy are the two possible etiologies, whereas infiltration, stretch, or exercise of the muscle are the causative factors. We report two cases of unilateral calf enlargement, one occurring after surgery for S1 radiculopathy with associated cramping, and the other after poliomyelitis.

[Retroperitoneal lymphadenectomy and disorders of ejaculation].

PubMed

Deiana, G; Ranieri, A; Micheli, E; Peracchia, G; Canclini, L P; Sironi, D; Levorato, C A; Lembo, A

1999-09-01

Retrograde ejaculation is a frequent and permanent complication after bilateral retroperitoneal lymphadenectomy (RPLND). Seminal emission and ejaculation are primarily under sympathetic control. Several studies after RPLND in patients with nonseminomatous testis cancer proved the role of preservation of the efferent fibers originating from the lumbar sympathetic ganglia. Based on the results of anatomical studies, a modified unilateral operative technique and nerve-sparing approach permit to preserve normal anterograde ejaculation without reduction of long-term survival.

High-resolution imaging of the retinal nerve fiber layer in normal eyes using adaptive optics scanning laser ophthalmoscopy.

PubMed

Takayama, Kohei; Ooto, Sotaro; Hangai, Masanori; Arakawa, Naoko; Oshima, Susumu; Shibata, Naohisa; Hanebuchi, Masaaki; Inoue, Takashi; Yoshimura, Nagahisa

2012-01-01

To conduct high-resolution imaging of the retinal nerve fiber layer (RNFL) in normal eyes using adaptive optics scanning laser ophthalmoscopy (AO-SLO). AO-SLO images were obtained in 20 normal eyes at multiple locations in the posterior polar area and a circular path with a 3-4-mm diameter around the optic disc. For each eye, images focused on the RNFL were recorded and a montage of AO-SLO images was created. AO-SLO images for all eyes showed many hyperreflective bundles in the RNFL. Hyperreflective bundles above or below the fovea were seen in an arch from the temporal periphery on either side of a horizontal dividing line to the optic disc. The dark lines among the hyperreflective bundles were narrower around the optic disc compared with those in the temporal raphe. The hyperreflective bundles corresponded with the direction of the striations on SLO red-free images. The resolution and contrast of the bundles were much higher in AO-SLO images than in red-free fundus photography or SLO red-free images. The mean hyperreflective bundle width around the optic disc had a double-humped shape; the bundles at the temporal and nasal sides of the optic disc were narrower than those above and below the optic disc (P<0.001). RNFL thickness obtained by optical coherence tomography correlated with the hyperreflective bundle widths on AO-SLO (P<0.001) AO-SLO revealed hyperreflective bundles and dark lines in the RNFL, believed to be retinal nerve fiber bundles and Müller cell septa. The widths of the nerve fiber bundles appear to be proportional to the RNFL thickness at equivalent distances from the optic disc.

Trigeminal Neuralgia, Glossopharyngeal Neuralgia, and Myofascial Pain Dysfunction Syndrome: An Update.

PubMed

Khan, Mohammad; Nishi, Shamima Easmin; Hassan, Siti Nazihahasma; Islam, Md Asiful; Gan, Siew Hua

2017-01-01

Neuropathic pain is a common phenomenon that affects millions of people worldwide. Maxillofacial structures consist of various tissues that receive frequent stimulation during food digestion. The unique functions (masticatory process and facial expression) of the maxillofacial structure require the exquisite organization of both the peripheral and central nervous systems. Neuralgia is painful paroxysmal disorder of the head-neck region characterized by some commonly shared features such as the unilateral pain, transience and recurrence of attacks, and superficial and shock-like pain at a trigger point. These types of pain can be experienced after nerve injury or as a part of diseases that affect peripheral and central nerve function, or they can be psychological. Since the trigeminal and glossopharyngeal nerves innervate the oral structure, trigeminal and glossopharyngeal neuralgia are the most common syndromes following myofascial pain dysfunction syndrome. Nevertheless, misdiagnoses are common. The aim of this review is to discuss the currently available diagnostic procedures and treatment options for trigeminal neuralgia, glossopharyngeal neuralgia, and myofascial pain dysfunction syndrome.

Trigeminal Neuralgia, Glossopharyngeal Neuralgia, and Myofascial Pain Dysfunction Syndrome: An Update

PubMed Central

Nishi, Shamima Easmin; Hassan, Siti Nazihahasma

2017-01-01

Neuropathic pain is a common phenomenon that affects millions of people worldwide. Maxillofacial structures consist of various tissues that receive frequent stimulation during food digestion. The unique functions (masticatory process and facial expression) of the maxillofacial structure require the exquisite organization of both the peripheral and central nervous systems. Neuralgia is painful paroxysmal disorder of the head-neck region characterized by some commonly shared features such as the unilateral pain, transience and recurrence of attacks, and superficial and shock-like pain at a trigger point. These types of pain can be experienced after nerve injury or as a part of diseases that affect peripheral and central nerve function, or they can be psychological. Since the trigeminal and glossopharyngeal nerves innervate the oral structure, trigeminal and glossopharyngeal neuralgia are the most common syndromes following myofascial pain dysfunction syndrome. Nevertheless, misdiagnoses are common. The aim of this review is to discuss the currently available diagnostic procedures and treatment options for trigeminal neuralgia, glossopharyngeal neuralgia, and myofascial pain dysfunction syndrome. PMID:28827979

Probabilistic Modeling Of Ocular Biomechanics In VIIP: Risk Stratification

NASA Technical Reports Server (NTRS)

Feola, A.; Myers, J. G.; Raykin, J.; Nelson, E. S.; Mulugeta, L.; Samuels, B.; Ethier, C. R.

2016-01-01

Visual Impairment and Intracranial Pressure (VIIP) syndrome is a major health concern for long-duration space missions. Currently, it is thought that a cephalad fluid shift in microgravity causes elevated intracranial pressure (ICP) that is transmitted along the optic nerve sheath (ONS). We hypothesize that this in turn leads to alteration and remodeling of connective tissue in the posterior eye which impacts vision. Finite element (FE) analysis is a powerful tool for examining the effects of mechanical loads in complex geometries. Our goal is to build a FE analysis framework to understand the response of the lamina cribrosa and optic nerve head to elevations in ICP in VIIP. To simulate the effects of different pressures on tissues in the posterior eye, we developed a geometric model of the posterior eye and optic nerve sheath and used a Latin hypercubepartial rank correlation coef-ficient (LHSPRCC) approach to assess the influence of uncertainty in our input parameters (i.e. pressures and material properties) on the peak strains within the retina, lamina cribrosa and optic nerve. The LHSPRCC approach was repeated for three relevant ICP ranges, corresponding to upright and supine posture on earth, and microgravity [1]. At each ICP condition we used intraocular pressure (IOP) and mean arterial pressure (MAP) measurements of in-flight astronauts provided by Lifetime Surveillance of Astronaut Health Program, NASA Johnson Space Center. The lamina cribrosa, optic nerve, retinal vessel and retina were modeled as linear-elastic materials, while other tissues were modeled as a Mooney-Rivlin solid (representing ground substance, stiffness parameter c1) with embedded collagen fibers (stiffness parameters c3, c4 and c5). Geometry creationmesh generation was done in Gmsh [2], while FEBio was used for all FE simulations [3]. The LHSPRCC approach resulted in correlation coefficients in the range of 1. To assess the relative influence of the uncertainty in an input parameter on the peak strains, we ranked and then normalized these coefficients, considering that normalized values 0.5 implied a substantial influence on the range of the peak strains in the optic nerve head (ONH). IOP and ICP were found to have a major influence on the peak strains in the ONH, as did optic nerve and LC stiffness. Interestingly, the stiffness of the sclera far from the scleral canal did not have a large influence on peak strains in ONH tissues; however, the collagen fiber stiffness in the peripapillary sclera and annular ring both influenced the peak strains within the ONH. We have created a physiologically relevant model that incorporated collagen fibers to study the effects of elevated ICP. Elevated ICP resulted in strains in the optic nerve that are not predicted to occur on earth: the upright or supine conditions. We found that IOP, ICP, lamina cribrosa stiffness and optic nerve stiffness had the highest association with these extreme strains in the ONH. These extreme strains may activate mechanosensitive cells that induce tissue remodeling and are a risk factor for the development of VIIP.

Speckle reduction during all-fiber common-path optical coherence tomography of the cavernous nerves

NASA Astrophysics Data System (ADS)

Chitchian, Shahab; Fiddy, Michael; Fried, Nathaniel M.

2009-02-01

Improvements in identification, imaging, and visualization of the cavernous nerves during prostate cancer surgery, which are responsible for erectile function, may improve nerve preservation and postoperative sexual potency. In this study, we use a rat prostate, ex vivo, to evaluate the feasibility of optical coherence tomography (OCT) as a diagnostic tool for real-time imaging and identification of the cavernous nerves. A novel OCT system based on an all single-mode fiber common-path interferometer-based scanning system is used for this purpose. A wavelet shrinkage denoising technique using Stein's unbiased risk estimator (SURE) algorithm to calculate a data-adaptive threshold is implemented for speckle noise reduction in the OCT image. The signal-to-noise ratio (SNR) was improved by 9 dB and the image quality metrics of the cavernous nerves also improved significantly.

Orbital and Intracranial Effects of Microgravity: 3T MRI Findings

NASA Technical Reports Server (NTRS)

Kramer, L. A.; Sargsyan, A.; Hasan, K. M.; Polk, J. D.; Hamilton, D. R.

2012-01-01

Goals and Objectives of this presentation are: 1. To briefly describe a newly discovered clinical entity related to space flight. 2. To describe normal anatomy and pathologic changes of the optic nerve, posterior globe, optic nerve sheath and pituitary gland related to exposure to microgravity. 3. To correlate imaging findings with known signs of intracranial hypertension.