Radiological Characteristics of Extraocular Muscles in Myasthenia Gravis Patients with Ocular Manifestations: A Case-Control Study.

PURPOSE: To analyze radiological characteristics of the extraocular muscles (EOMs) in myasthenia gravis (MG) patients with ocular manifestations. PATIENTS AND METHODS: This retrospective case-control study included all MG cases with ocular manifestations, who attended a neuro-ophthalmology clinic at a university hospital, Bangkok, from April 2009 to June 2018. They experienced double vision and ophthalmoplegia. Control participants had normal eye movements. Orbital scans were thoroughly reviewed. We measured muscle thickness (MT) of the superior rectus, inferior rectus, medial rectus and lateral rectus muscles in both eyes using magnetic resonance imaging or computed tomography scan. The sum of the muscle thickness at all sites was calculated (MTsum). Comparisons of the mean MT of each muscle type and the mean MTsum between the MG and control groups were performed by using Student's t-test. MRI signal intensities of the EOMs were also recorded. RESULTS: Twenty MG cases and 20 controls were included in the study. The mean MTsum was 23.7 (standard deviation 4.8) mm in the MG group and 32.6 (3.5) mm in the controls. There were statistically significant differences between the two groups with respect to the mean MT and mean MTsum (p <0.001). In the MG group, there was a negative correlation between the MTsum and disease duration (p= 0.03). By using coronal T2-weighted orbital MRI with fat suppression (T2W/FS), the most frequent finding was isointensity with central hypointensity of the EOMs in the MG group. CONCLUSION: Atrophic EOMs were frequently found in the MG group, particularly in chronic cases. Isointensity with central hypointensity of EOMs on T2W/FS was also common in the MG group. These findings highlight the importance of muscle involvement in MG and may be helpful for clinical decision-making.

Comparison of Visual Acuity Measurement Using Three Methods: Standard ETDRS Chart, Near Chart and a Smartphone-Based Eye Chart Application.

PURPOSE: To validate the Rosenbaum near vision card (Near Chart) and a smartphone-based visual acuity (VA) test (Eye Chart) against a standard retro-illuminated Early Treatment Diabetic Retinopathy Study (ETDRS) chart within participants. MATERIALS AND METHODS: A cross-sectional study of participants aged ≥18 years was conducted. VA was measured in all participants using the ETDRS chart, Near Chart and smartphone-based Eye Chart application, respectively. VA was converted to logarithm of the minimum angle of resolution (logMAR) for statistical analysis. Eyes with ETDRS VA worse than 1.0 logMAR (20/200) were excluded. The main outcome measures were levels of agreement between VA measured using the Near Chart or Eye Chart application vs the ETDRS chart. RESULTS: A total of 295 eyes of 151 participants were included. One hundred participants (66.2%) were female and the mean age was 64.3 ± 12.5 years. Educational level was high school or below for 49% of participants and at Bachelor's degree or above for 51%. The median logMAR VAs of all eyes tested using the ETDRS chart, Near Chart and Eye Chart application were 0.1, 0.0 and 0.1, respectively. The median VA difference between the Near Chart vs ETDRS chart and Eye Chart application vs ETDRS chart was 0.0 logMAR in both cases for both the right eye (OD) and left eye (OS). Intraclass correlation coefficient (ICC) demonstrated a strong positive correlation between VA tested with the Near Chart vs ETDRS chart (OD: ICC=0.85; p<0.001, OS: ICC=0.77; p<0.001) and Eye Chart application vs ETDRS chart (OD: ICC=0.88; p<0.001, OS: ICC=0.74; p<0.001). CONCLUSION: VA measurements with the Near Chart and smartphone-based Eye Chart application corresponded well to the standard ETDRS chart, suggesting potential utility of alternative portable VA tests for in-office or remote vision monitoring, particularly during periods of physical distancing such as the Coronavirus disease 2019 (COVID-19) era.

Clinical Characteristics of HIV-Associated Optic Neuritis.

INTRODUCTION: Acute optic neuritis (ON) has been increasingly reported in patients infected with human immunodeficiency virus (HIV). We aimed to describe clinical characteristics of HIV-infected patients with ON. MATERIALS AND METHODS: This observational retrospective study was performed from January 2008 to January 2016 in a university hospital in Bangkok, Thailand. Demographic data and clinical manifestations were retrospectively reviewed. RESULTS: We included 10 HIV-infected patients and divided them into two groups: infectious and non-infectious ON. There were six patients in the infectious ON group (five males, mean age 33.6 years, median CD4 cell counts during ON episodes 36.5 cells/µL, high viral loads, median initial visual acuity [VA] 1.7, median VA difference [initial VA - follow-up VA] 0). Four patients developed cryptococcal meningitis and 2 developed neuro-syphilis. They were treated with amphotericin B plus fluconazole and penicillin G sodium, respectively. There were four patients in the non-infectious ON group (two males, mean age 44.3 years, median CD4 cell count during acute ON 157.5 cells/µL, undetectable viral loads, median initial VA 1.3, and median VA difference 1.2). They were given corticosteroid treatments. There were no statistically significant differences between the two groups with respect to age, sex, and initial VA. There were statistically significant differences in median VA difference and median CD4 cell counts between the two groups (p=0.02 and 0.03, respectively). There was a significant correlation between CD4 counts and duration in three non-infectious ON patients treated with antiretroviral therapy (ART, p<0.001). DISCUSSION: Patients with infectious ON had low initial CD4 counts and high viral loads. Patients with non-infectious ON had increasing CD4 cell counts and undetectable HIV viral load following ART. The findings are highly suggestive of immune reconstitution inflammatory syndrome. The CD4 cell counts and viral loads may help to identify the type of acute ON in HIV-infected patients and establish proper therapies.

Etiologies of Acute Optic Neuritis in Thailand: An Observational Study of 171 Patients.

PURPOSE: To analyze the demographic patterns, clinical characteristics and etiologies of acute optic neuritis (ON). METHODS: This retrospective observational study included patients with acute ON who presented to a university hospital in Bangkok, Thailand, between January 2010 and March 2020. The demographic details, clinical characteristics and etiologies of acute ON were evaluated. RESULTS: A total of 171 patients were included in the study (78.4% [n=134] female; mean age 45 years [standard deviation 15.4 years]; 32.2% [n=55] bilateral involvement). The most common type of acute ON was idiopathic (51.5%), followed by neuromyelitis optica spectrum disorder (NMOSD, 30.9%), other autoimmune disorders (9.9%), myelin oligodendrocyte glycoprotein antibody-associated disorder (MOGAD, 5.3%), multiple sclerosis (MS, 1.8%), and postinfection (0.6%). In the other autoimmune disorders group, 2 patients developed systemic lupus erythematosus (1.2%), 2 Sjogren's syndrome (1.2%), 1 RA (0.6%), 1 anti-NMDAR (0.6%), 3 anti-Jo1 (1.8%), 2 c-ANCA (1.2%), 1 anti-centromere (0.6%), and 5 nonspecific autoimmune disorders (2.9%). In the idiopathic group, 38.6% developed single isolated ON, 1.8% relapsing isolated ON and 11.1% chronic relapsing inflammatory optic neuropathy. CONCLUSION: The most common form of acute ON in this study, similar to other Asian countries, was idiopathic. Idiopathic-ON shared some phenotypes with NMOSD and MOGAD. We also reported patients with anti-NMDAR, anti-Jo1, c-ANCA and anti-centromere disorders. Improvements in antibody detection have widened the range of possible etiologies of acute ON. The study highlighted the important role of antibodies in creating effective treatments in the future.

Evaluation of Retinal Nerve Fiber Layer and Ganglion Cell Layer Thickness in Alzheimer's Disease Using Optical Coherence Tomography.

OBJECTIVE: To evaluate the feasibility of using optical coherence tomography (OCT) for the detection of Alzheimer's disease (AD), by measuring the thickness of the retinal nerve fiber layer (RNFL) and the ganglion cell layer and inner plexiform layer (GCL-IPL). MATERIAL AND METHODS: This was a single-center, cross-sectional study. The study included 29 patients with AD (mean age ± standard deviation: 75.61 ± 6.24 years) and 29 healthy age- and sex-matched controls. All participants underwent cognitive evaluations using the Montreal Cognitive Assessment test. Measurements of the RNFL thickness, as well as GCL-IPL thickness, were obtained for all participants using OCT. Both RNFL and GCL-IPL parameters were adjusted for best-corrected visual acuity, hypertension, diabetes and dyslipidemia. RESULTS: The mean RNFL thickness was significantly thinner in the AD group than in the control group (85.24 and 90.68 µm, respectively, adjusted P=0.014). The superior quadrant was thinner in the AD group (adjusted P=0.033). The thicknesses did not differ significantly between groups for the other quadrants. The mean GCL-IPL thickness in the AD (68.81 µm) was significantly thinner than that in the controls (76.42 µm) (adjusted P=0.014). Overall, there was a negative correlation between age and mean RNFL; and between age and GCL-IPL thickness (r=-0.338, P=0.010 and r=-0.346, P=0.008, respectively). CONCLUSION: The mean RNFL and GCL-IPL thicknesses were thinner in the AD group than in the control group. These findings suggest that RNFL and GCL-IPL thickness may be biological markers for AD.

Initial Treatment Response in Ocular Myasthenia Gravis: A Comparison Between Low and Moderate Doses of Prednisolone.

PURPOSE: To evaluate the initial treatment response to low doses of prednisolone, compared with moderate doses, in ocular myasthenia gravis (OMG). PATIENTS AND METHODS: A retrospective chart review of patients with adult-onset (age ≥15 years old) OMG, who were treated with prednisolone, was conducted. Subjects were divided into two groups according to their prednisolone dosing regimen. The low-dose group was defined as those with an average 12-week cumulative dose of prednisolone <0.435 mg/kg/day and the moderate-dose group averaged 0.435-1.000 mg/kg/day. The primary outcome of interest was the comparison of clinical response to prednisolone at 12 weeks between the low-dose and moderate-dose groups. The secondary outcome was the difference in adverse events between treatment groups. RESULTS: Of 34 subjects, 16 subjects (47.1%) were male. The mean age at onset was 44.0±18.1 years. The most common presenting ocular feature was ptosis with ophthalmoplegia (22 subjects, 64.7%), followed by isolated ptosis (nine subjects, 26.5%) and isolated ophthalmoplegia (three subjects, 8.8%). Half of the subjects were treated with low-dose prednisolone and the other half were treated with moderate-dose prednisolone. There were no substantial differences in baseline characteristics between treatment groups. After 12 weeks of treatment, nine of 17 subjects (52.9%) and 13 of 17 subjects (76.5%) in the low- and moderate-dose groups, respectively, were regarded as responsive to the prednisolone treatment (P=0.28). Adverse events were exclusively observed in the moderate-dose group. CONCLUSION: Treatment of OMG with an average 12-week cumulative dose of prednisolone <0.435 mg/kg/day (low dose) shows a comparable responsive outcome to 0.435-1.000 mg/kg/day of prednisolone (moderate dose). Treating OMG with low-dose prednisolone can minimize prednisolone-related adverse events. However, a prospective randomized controlled trial with a larger study population is warranted in order to gain more insight into the proper dosage of prednisolone for OMG.

Isolated Horner syndrome as a rare initial presentation of nasopharyngeal carcinoma: a case report.

BACKGROUND: Horner syndrome refers to a set of clinical presentations resulting from disruption of sympathetic innervation to the eye and adnexa. Classically, the clinical triad consists of ipsilateral blepharoptosis, pupillary miosis, and facial anhidrosis. Ocular sympathetic denervation may signify life-threatening causes. Timely investigation and accurate diagnosis are essential in patients with oculosympathetic denervation. CASE PRESENTATION: A 33-year-old Asian man with a heavy smoking habit presented with a 3-week history of left ptosis and no other complaints. His visual acuity was 20/20 bilaterally. An ophthalmic examination was significant for mild ptosis of his left eyelid and anisocoria (smaller left pupil), which was greater in the dark. Both pupils reacted to light briskly without an afferent pupillary defect. Anhidrosis was found on the medial side of the left forehead. A 10% cocaine test was positive. At his first visit, neurologic examination was unremarkable. Comprehensive radiological investigations were scheduled for a left-sided isolated Horner syndrome. Two weeks after his first visit, he experienced a left-sided headache along with ipsilateral Horner syndrome. Neurologic examination revealed hypoesthesia in the left cranial nerve V1-3 territories. Emergent computed tomography angiography was suspected for petrous part of the left internal carotid artery (ICA) dissection. Magnetic resonance imaging demonstrated an enhancing infiltrative lesion with its epicenter at the left sphenoid bone. The lesion encased the left ICA and invaded the left Meckel cave. Rhinoscopy with incisional biopsy revealed squamous cell nasopharyngeal carcinoma. CONCLUSION: This case involved an unusual initial presentation of nasopharyngeal carcinoma: isolated Horner syndrome with clinical progression to adjacent structures. Infiltration involving the Meckel cave and ICA at the foramen lacerum can present as postganglionic Horner syndrome associated with trigeminal pain and hypoesthesia. These clinical findings may mimic carotid artery dissection on computed tomography angiography. Detailed magnetic resonance imaging with careful attention to the skull base should be performed.

Isolated optic neuritis with a concurrent abnormal trigeminal nucleus on imaging: case report of a rare complication of herpes zoster ophthalmicus.

BACKGROUND: Herpes zoster ophthalmicus (HZO) is an inflammation related to reactivation of the latent varicella zoster virus (VZV), involving the ophthalmic branch of the trigeminal nerve. Optic neuritis (ON), a rare ocular complication following HZO, has been reported in 1.9% of HZO-affected eyes. Most previous cases occurred simultaneously with other ocular complications, especially orbital apex syndrome. Moreover, detailed magnetic resonance imaging (MRI) with diffusion weighted imaging of the optic nerve and trigeminal nucleus in HZO-related ON has been rarely reported. We report a case of postherpetic isolated ON with a concurrent abnormal trigeminal nucleus on imaging. CASE PRESENTATION: A healthy 58-year-old female presented with sudden painful visual loss in her right eye for 2 days. Four weeks before the presentation, her right eye was diagnosed with HZO, and she received intravenous acyclovir for 10 days. Ophthalmic examination revealed a visual acuity of light perception and 20/20 in the right and left eyes, respectively. A relative afferent pupillary defect was present in the right eye. Neurological examination was significant for hypoesthesia in the area of the HZO. A clinical diagnosis of HZO-related right retrobulbar ON was made, and other causes of atypical ON were excluded. MRI showed enhancement and restricted diffusion of the right-sided optic nerve with linear hyperintense T2 of the right-sided spinal trigeminal nucleus and tract (STNT) along the brainstem. She received 14 days of intravenous acyclovir and 5 days of methylprednisolone. Both were switched to an oral route for 2 months. After the completion of treatment, the visual acuity was counting fingers and 20/20 in the right eye and left eye, respectively. Stable brainstem STNT abnormalities and resolution of ON were found radiologically. CONCLUSIONS: Isolated ON is a rare ocular complication following HZO. An abnormal high signal of STNT on a T2 weighted image may be present, which may be a clue for VZV-associated complications, such as HZO-related ON, especially in cases lacking an obvious history of HZO or other concomitant ocular complications. Prompt treatment with both acyclovir and corticosteroids should be started. Restricted diffusion of the optic nerve may be a predictor for poor visual recovery.

Juvenile Ocular Myasthenia Gravis: Presentation and Outcome of a Large Cohort.

BACKGROUND: Isolated ocular myasthenia gravis (MG) is sparingly common in children relative to adults, ranging from 71% to 93% of all children with MG. PURPOSE: We aimed to characterize the ocular manifestations and outcomes in children with isolated ocular MG. METHODS: Medical records of consecutive 62 subjects less than 15 years of age with ocular MG, were retrospectively reviewed. Demographic data, presenting ocular features, types and variabilities of duction limitation, MG confirmatory tests, types of and responses to treatment, and generalized MG conversion were reviewed. RESULTS: Mean age at onset and follow-up time were 49 months (range, one to 173 months) and 95 months (range, six to 226 months), respectively. Female-to-male ratio was 1.5:1. Initially, ptosis was found in 60 subjects (96.8%), while duction limitation was observed in 28 subjects (45.2%). Total ophthalmoparesis was the most common type of duction limitation. Variability of duction limitation was found in 68% of subjects during the follow-up. Pyridostigmine alone was the most common medication used (48.4%); ptosis was more responsive to therapy than duction limitation. Conversion to generalized MG occurred in 19.4% of subjects, with a mean interval to conversion of nine months after symptom onset. Most conversions (91.7%) occurred in the first two years. CONCLUSIONS: Ptosis was more responsive to treatment than duction limitation. Thus other treatment modalities, as well as strabismic amblyopia screening, should be considered in children with prolonged duction limitation that is refractory to medication. In contrast with adults, a much lower proportion of children converted to generalized MG. This may explain the higher prevalence of isolated ocular MG among the juvenile population.

Bilateral oculomotor ocular neuromyotonia: a case report.

BACKGROUND: Ocular neuromyotonia (ONM) is characterized by episodic diplopia, which is usually triggered by prolonged eccentric gaze of the affected extraocular muscles. The spell is characterized by involuntary, occasionally painful, sustained contraction of one or more extraocular muscles innervated by the oculomotor, trochlear, or abducens nerve. ONM usually occurs as a late consequence of radiotherapy around the parasellar area, although idiopathic cases have been reported. Most cases are unilateral; however, bilateral ONM has occasionally been described. CASE PRESENTATION: A 60-year-old woman presented with a 4-month history of episodic, painful, horizontal binocular diplopia. She underwent external beam radiotherapy to the skull base for treatment of nasopharyngeal carcinoma. The tumor was well controlled. General neurological examination findings were unremarkable. Neuro-ophthalmic examination revealed normal visual acuity, visual fields, pupils, and fundi. Ocular alignment showed orthotropia with normal ocular motility. Myasthenic eyelid signs were absent. However, she developed episodes of involuntary sustained contraction of the medial rectus muscle following prolonged eccentric gaze toward the affected medial rectus muscle, which resulted in esotropia upon returning to the primary position. The esotropic episodes spontaneously resolved after approximately 2 min. These spells affected both medial rectus muscles. Both pupils remained normal throughout the examination. Magnetic resonance imaging revealed neither brain parenchyma/brain stem lesions nor tumor recurrence. Her symptoms were successfully treated with carbamazepine. CONCLUSIONS: Episodic esotropia in the adducting eye following prolonged horizontal eccentric gaze is a significant characteristic of ONM affecting the bilateral medial rectus muscles (i.e., bilateral oculomotor ONM). In spite of its extreme rarity, ONM should be considered as a differential diagnosis of episodic diplopia, especially in patients with a history of radiotherapy around the parasellar area. Careful examination with prolonged eccentric gaze should be performed to achieve a correct diagnosis and avoid an extensive unnecessary workup.

Atypical central retinal artery occlusion as the first presentation of POEMS syndrome: a case report.

BACKGROUND: POEMS syndrome is a plasma cell disorder, which clinically manifests from paraneoplastic syndrome: polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, and skin changes. The most common ocular manifestation is optic disc swelling, whereas other ocular manifestations; cystoid macular edema, serous macular detachment, venous sinus thrombosis, infiltrative orbitopathy, uveitis, neovascularization of the disc, peripapillary choroidal neovascularization and optic disc drusen, had also been reported. CASE PRESENTATION: A 52-year-old Thai man presented with 5-day sudden painless visual loss in the left eye. Ocular examination revealed visual acuity of 20/20 and no light perception in the right and left eye, respectively. Right fundoscopic examination was significant for hyperemic generalized optic disc swelling. Left fundoscopic examination revealed opaque and edematous entire retina giving the appearance of central retinal artery occlusion (CRAO) along with pallid "chalky white" optic disc swelling. Fluorescein angiography showed profound leakage of bilateral optic nerve heads and arteriolar filling defect in macular area along with leakage of small retinal arterioles in the left eye. Indocyanine green angiography demonstrated choroidal filling defect in the left eye only. Neuroimaging showed enhancement and luminal narrowing of left internal carotid artery, early subacute watershed infarctions in the left cerebral hemisphere and pachymeningeal enhancement. Cerebrospinal fluid analysis revealed high protein level with normal opening pressure. Intravenous methylprednisolone was initially started without any benefit. After extensive investigations, diagnosis of "POEMS syndrome" was made based on polyneuropathy, elevated lambda light chain level, elevated plasma vascular endothelial growth factor (VEGF), hepatomegaly, spinal sclerotic bone lesions, and thrombocytosis. Furthermore, sural nerve biopsy demonstrated neuropathy and positive VEGF staining. He was treated with eight cycles of bortezomib, cyclophosphamide and dexamethasone (BorCyDex). Polyneuropathy and thrombocytosis had remarkably improved after 2nd cycle, whereas, visual impairment had shown no recovery. Hepatomegaly was significantly reduced after the completion of BorCyDex. Our case eventually received autologous hematopoietic stem cell transplantation with high dose melphalan. CONCLUSIONS: To our knowledge, we illustrated the first patient given CRAO as the first presentation and ocular finding ever reported in POEMS syndrome. Both cerebral and ocular infarctions were presumably the result of VEGF-induced cranial vasculopathy as evidenced by neuroimaging.

Occipital lobe infarction: a rare presentation of bilateral giant cavernous carotid aneurysms: a case report.

BACKGROUND: Cavernous carotid aneurysm (CCA) represents 2-9% of all intracranial aneurysms and 15% of internal carotid artery (ICA) aneurysms; additionally, giant aneurysms are those aneurysms that are > 25 mm in size. Bilateral CCAs account for 11-29% of patients and are commonly associated with structural weaknesses in the ICA wall, secondary to systemic hypertension. CCAs are considered benign lesions, given the low risk for developing major neurologic morbidities (i.e., subarachnoid hemorrhage, cerebral infarction, or carotid cavernous fistula). Moreover, concurrent presentation with posterior circulation cerebral infarction is even rarer, given different circulation territory from CCA. Here, we report on a patient with bilateral giant CCAs who presented with both typical and atypical symptoms. CASE PRESENTATION: An 88-year-old hypertensive woman presented with acute vertical oblique binocular diplopia, followed by complete ptosis of the right eye. Ophthalmic examination showed dysfunction of the right third, fourth, and sixth cranial nerves. Further examination revealed hypesthesia of the areas supplied by the ophthalmic (V1) and maxillary (V2) branches of the right trigeminal nerve. Bilateral giant cavernous carotid aneurysms, with a concurrent subacute right occipital lobe infarction, were discovered on brain imaging and angiogram. Additionally, a prominent right posterior communicating artery (PCOM) was revealed. Seven months later, clinical improvement with stable radiographic findings was documented without any intervention. CONCLUSIONS: Dysfunction of the third, fourth, and sixth cranial nerves, and the ophthalmic (V1) and maxillary (V2) branches of the trigeminal nerves, should necessitate brain imaging, with special attention given to the cavernous sinus. Despite unilateral symptomatic presentation, bilateral lesions cannot be excluded solely on the basis of clinical findings. CCA should be included in the differential diagnosis of cavernous sinus lesions. Although rare, ipsilateral posterior circulation cerebral infarction (i.e., occipital lobe infarction) can occur in CCA patients, presumably as a result of distal embolization through an ipsilateral, prominent PCOM. Spontaneous clinical improvement with stable radiographic support may occur.

Clinical characteristics and long-term visual outcome of optic neuritis in neuromyelitis optica spectrum disorder: A comparison between Thai and American-Caucasian cohorts.

BACKGROUND: Neuromyelitis optica spectrum disorder (NMOSD) occurs more commonly in Asian than Caucasian populations. Few studies have examined the clinical features and visual outcome of optic neuritis (ON) within NMOSD in different racial populations. The objective of this study was to compare the clinical characteristics and long-term visual outcome of a Thai and an American-Caucasian cohort with NMOSD-related ON. METHODS: Medical records including brain and orbital magnetic resonance imaging (MRI) of 16 consecutive subjects who developed visual loss due to ON as part of NMOSD evaluated at a single American tertiary referral center between 2006 and 2015 were reviewed and compared to those of 16 consecutive similar subjects evaluated at a single Thai tertiary referral center between 2010 and 2016. These cohorts represented the total number of NMOSD-related ON subjects seen during that time at those institutions. Statistical analyses were used for continuous and categorical data sets, and multiple regression analysis was used to adjust for differences in duration of follow-up and number of episodes of ON in each affected eye. RESULTS: All subjects within the Thai cohort were Asian, while the American cohort initially consisted of 14 Caucasian, 1 Asian and 1 African-American subject, but the latter two were excluded from analysis. In the Thai cohort, ON occurred in 21 eyes, with a total of 19 episodes, while in the American-Caucasian cohort ON occurred in 22 eyes, with a total of 21 episodes. Aquaporin 4 (AQP4)-antibody was positive in all subjects except for one American-Caucasian subject. The mean follow-up time was 17.8 (± 16.0) and 52.8 (± 51.9) months for the Thai and American-Caucasian populations, respectively. There was no difference between the two cohorts with respect to gender, age of NMOSD and NMOSD-related ON onset, initial clinical presentation of NMOSD, initial visual acuity and automated visual fields, prevalence of swollen optic disc in the acute phase, presence of pain on the affected side, mean time of onset of ON symptoms to MRI examination, distribution of segmental involvement of the anterior visual pathway abnormalities based on MRI findings, mean time of onset of ON symptoms to treatment, final visual acuity and automated visual fields. However, a higher proportion of Thai affected eyes were found to have an initial visual acuity of 20/200 or worse compared with the American-Caucasian cohort. Azathioprine was the most common maintenance treatment (75%) used among Thai subjects in contrast to rituximab (78.6%) among American-Caucasian subjects. CONCLUSION: Despite the different prevalence among Thai and American-Caucasian populations, the clinical characteristics of ON in the NMOSD were very similar across these two populations, other than for more severe visual loss initially among Thai subjects. Notably, long-term visual outcome did not differ between these cohorts despite significant difference in the maintenance treatment regimen. This study did not assess neurological status or outcome.

Syphilitic Optic Neuropathy: Re-emerging Cases Over a 2-Year Period.

We report 7 cases of syphilitic optic neuropathy during a 2-year period. All patients were newly diagnosed with human immunodeficiency virus (HIV) infection. Six cases (86%) initially presented with swollen optic disc either unilaterally or bilaterally. Blind spot enlargement was the most common type of visual field defect. Final visual acuity of at least 20/25 was achieved together with visual field improvement and resolution of swollen optic disc. Optic nerve involvement can be the first manifestation of syphilis and HIV co-infection. Syphilitic optic neuropathy has an excellent prognosis if the disease diagnosed promptly and treated properly.

Pediatric primary optic nerve sheath meningioma.

Primary optic nerve sheath meningioma (PONSM) is extremely rare among children. We report two cases of pediatric PONSM. The first case was a 12-year-old boy who presented with gradual visual loss of his right eye and was found to be associated with neurofibromatosis type 2. The second case was a 10-year-old boy who presented with gradual proptosis of his left eye with normal visual acuity. Severe visual loss is a common clinical manifestation of pediatric PONSM. Although the visual acuity in the second case was normal, his vision rapidly deteriorated to 20/200. In both cases, the diagnosis of PONSM was confirmed by magnetic resonance imaging, and a successful tumor growth control was achieved after stereotactic radiotherapy was implemented.

Anterior ischemic optic neuropathy due to biopsy-proven giant cell arteritis in Thai patients.

Giant cell arteritis is a systemic granulomatous vasculitis affecting medium to large arteries. An arteritic anterior ischemic optic neuropathy is the most common cause of permanent visual loss. Giant cell arteritis is very rare among Asians. We report six patients with biopsy-proven arteritic anterior ischemic optic neuropathy. Demographic data, clinical manifestations, laboratory findings, treatment, and visual outcome are described in detail and compared with Caucasian patients. We found no differences in any clinical features except for sex preference. Moreover, perioptic nerve sheath enhancement was observed in half of our patients.

Ischemic retinal vasculitis in an 18-year-old man with chickenpox infection.

Ocular involvement after primary infection with varicella zoster virus is very rare. We report a case of a healthy 18-year-old man who presented with unilateral ischemic retinal vasculitis 10 days after the onset of chickenpox. He developed acute severe visual loss and a relative afferent pupillary defect in his right eye. Fundus imaging, optical coherence tomography, fundus fluorescence angiography, and electrophysiologic studies confirmed the diagnosis of retinal vasculitis, which led to generalized retinal ischemia. Although aggressive treatment with systemic steroids and antiviral drugs was administered, a poor visual outcome still resulted.

Sclerosing therapy for orbital lymphangioma using sodium tetradecyl sulfate.

PURPOSE: To describe the results of intralesional injection of the sclerosing agent sodium tetradecyl sulfate in patients with orbital lymphangioma. METHODS: Four young patients with a history of orbital lymphangioma were treated on one or more occasions with percutaneous puncture and injection of sodium tetradecyl sulfate under computed tomography guidance. Resolution of the signs and symptoms, complications resulting from surgery, and recurrence of bleeding were studied. RESULTS: Three patients with a long-standing history of unilateral proptosis and one patient with progressive unilateral visual loss from multiple recurrent orbital hemorrhages were studied. Treatment ranged from one to three sodium tetradecyl sulfate injections. All patients showed improvement of their signs and symptoms after treatment. A decrease in the size of lesions was demonstrated by orbital imaging. Visual acuity and intraocular pressure remained unchanged. Complications included transient postoperative localized inflammation in all cases and transient ophthalmoparesis in one patient. Follow-up time ranged between 15 and 36 months, during which no recurrence of bleeding was observed. CONCLUSIONS: Our study suggests that intralesional injection of sodium tetradecyl sulfate under computed tomography guidance is an effective treatment for patients with orbital lymphangioma and is not associated with vision-threatening complications.

Dural carotid cavernous sinus fistula: ocular characteristics, endovascular management and clinical outcome.

OBJECTIVE: To describe the ocular findings, endovascular treatment, and clinical outcome in patients with dural carotid cavernous sinus fistula (CCF). MATERIAL AND METHOD: A retrospective evaluation of 80 consecutive patients who underwent examination and treatment for dural CCF between January 1997 and December 2004 was performed. RESULTS: Fifty females and 30 males, with an average age of 49 years (from 6 -80 years) participated in this study. All patients had more than one clinical signs and symptoms including proptosis (84%), arterialization of conjunctival vein (93%), chemosis (42%), cranial nerve palsy (52%), elevated intraocular pressure (51%), and optic neuropathy (13%). Diminished vision was found in 43% of the patients. The degree of visual deficit ranged from 20/40 to no light perception. After angiographic evaluation, patients were classified to CCF Barrow's type B 14%, type C 15%, and type D 71%. Endovascular treatment by transvenous and/or transarterial embolization was performed in 60 patients (75%). Carotid-angular compression therapy was solely performed in 19 patients (24%) and was used as an adjunct to endovascular treatment in 30 patients (38%). The follow-up period ranged from 6 to 94 months. Clinical cure was achieved in 41 patients (51%) and improvement in 30 patients (38%). Anatomical cure was demonstrated by angiogram in 50 patients (63%). Intra-operative complications were found in three patients including ophthalmic artery occlusion and cerebral infarction. Eight patients experienced transient aggravation of symptoms including increased proptosis, elevation of intraocular pressure, choroidal detachment that required suprachoroidal drainage, and venous stasis retinopathy. Ophthalmic vein thrombosis resulting in central retinal vein occlusion was developed in three patients and finally caused severe visual deficit. There was no operative mortality. CONCLUSION: Selective management with endovascular therapy and manual compression are the effective treatment for dural CCF. However sight-threatening complications can develop after therapy due to progressive ophthalmic vein thrombosis and should be carefully monitored.

A reinterpretation of certain disorders affecting the eye muscles and their tissues.

Recent discoveries about the orbital tissues prompt a re-evaluation of the way that clinicians think about disorders affecting the extraocular muscles, their nerves and motoneurons in the brainstem. The revolutionary discovery that the orbital layers of the extraocular muscles insert not onto the eyeball, but into fibromuscular pulleys that guide the orbital layers, provides explanations for the kinematic properties of eye rotations and clinical findings in some patients with strabismus. The demonstration that all extraocular fibers types, except pale global fibers, lack synaptic folding provides an explanation for why saccades may remain fast in patients with limited ocular mobility due to myasthenia gravis. More than one mechanism may account for the observation that patients with disorders affecting the eye muscles or their nerves can present with the appearance of central disorders of ocular motility, such as internuclear ophthalmoplegia. New approaches to analyzing saccades in patients with disjunctive eye movements provide the means to identify disorders affecting the peripheral or central components of the ocular motor system, or both.