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.

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.

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.

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.

Choroidal effusion following continuous positive airway pressure treatment.

A 46-year-old man was diagnosed with obstructive sleep apnea and began using a nasal continuous positive airway pressure (CPAP) during sleep for a month. He presented with the complaint of a painful blurred vision in his left eye upon awakening two days earlier. His visual acuity was 20/25 both eyes. There was a mild anterior chamber reaction in the left eye. Fundus examination showed a localized choroidal effusion at the inferotemporal part of the left retina. The patient received topical 0.1% dexamethasone four times daily and temporarily discontinued the CPAP. By one week after treatment, the choroidal effusion was completely resolved

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.

Anterior ischemic optic neuropathy in patients younger than 50 years.

PURPOSE: To characterize anterior ischemic optic neuropathy (AION) in patients younger than 50 years. DESIGN: Retrospective study. METHODS: Records of all AION patients seen between 1989 and 2006 were reviewed. Patients younger than 50 years when initial visual loss occurred were included. RESULTS: Of 727 consecutive patients with AION, 169 (23%) were younger than 50 years (median, 43 years; range, 13 to 49 years; 58% men; 93% White). Involvement was unilateral in 59% of patients and bilateral in 41%. At least one cardiovascular risk factor was found in 74% of patients. Hypercoagulable states and vasculitis were found in 8%. An underlying small or anomalous optic disk was found in 92% of eyes (210/230). Isolated disk anomalies (without systemic risk factors) were present in 26% of eyes. Final visual acuities were 20/40 or better in 64% of eyes and 20/200 or worse in 22%. Among patients with bilateral involvement, final visual acuity was similar in the two eyes in 70% of patients. Anemia and type I diabetes were associated significantly with fellow eye involvement. Recurrent AION in the same eye occurred in 6% of patients. CONCLUSIONS: AION in younger patients is not uncommon and represents 23% of AION patients in a tertiary neuro-ophthalmic service. Except for giant cell arteritis, ocular and systemic risk factors and associated disorders are similar to those described in older AION patients. Younger AION patients have better visual acuity outcomes but a higher risk of fellow eye involvement than older AION patients.

Contact lens-related microbial keratitis.

OBJECTIVE: To review the clinical and microbiological profile in patients with contact lens-related microbial keratitis (CLRMK). MATERIAL AND METHOD: Hospital records of 435 patients with a diagnosis of microbial keratitis seen at Ramathibodi Hospital from January 1998 to December 2002 were retrospectively reviewed. All patients with CLRMK were included in the present study. RESULTS: Of the 435 cases, 81 (18.6%) were related to contact lens use. The disposable or frequent replacement of lenses were the most common lens-wearing type. Thirty-four percent of patients did not practice proper contact lens care and 67% wore contact lenses overnight. Corneal cultures were performed in 58 of 81 cases (72%) and were positive in 42 of 58 cases (72%). Pseudomonas aeruginosa was the most common organism (59%), followed by Klebsiella pneumoniae (11%). Polymicrobial infection was found in 19 cases. Most of the patients responded to medical treatment that led to the healing of ulcers whereas four patients required therapeutic penetrating keratoplasty. Most, of the organisms were sensitive to antibiotics. After treatment, 43% of the patients have continued contact lenses-wearing. CONCLUSION: CLRMK remains an essential problem in Thailand. Soft contact lens wear and overnight wearing seem to be the most important risk factors. Although the treatment outcome with medical therapy is good, keratitits may result in loss of vision. Ophthalmologist should warn contact lens wearers of this potential problem and instruct them on how to care for their lenses.

Effects of topical anti-inflammatory agents in a botulinum toxin B-induced mouse model of keratoconjunctivitis sicca.

PURPOSE: The aim of this study was to compare the effects of topical nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroid, doxycycline, and artificial tears for the treatment of ocular surface damage in the Botulinum toxin B (BTX-B)-induced mouse model of dry eye. METHODS: CBA/J mice were randomized into 2 experimental groups of 35 animals each. The control group received a transconjunctival injection of 0.05 mL of saline into the left lacrimal gland, and another group was injected with 0.05 mL of 20 milliunits BTX-B solution (SPSS, Inc., Chicago, IL). Three (3) days after intralacrimal gland injections, each group was equally randomized into 7 subgroups (n=5 each) to receive treatment unilaterally into their left eyes with topical artificial tears (0.5% carboxymethylcellulose sodium), 0.1% fluorometholone, 0.1% nepafenac, 0.4% ketorolac, 0.09% bromfenac, 0.1% diclofenac, or 0.025% doxycycline. Tear volume, ocular surface changes, and spontaneous blink rate were evaluated in each of the 14 experimental subgroups. RESULTS: Topical fluorometholone, nepafenac, and doxycycline significantly improved corneal surface staining in the BTX-B-injected mice within 2 weeks of treatment. Topical ketorolac, diclofenac, and bromfenac, applied twice-daily, partially reduce corneal staining, and did so more slowly by the 4-week time point. In comparison, topical artificial tear-treated mice did not demonstrate significant improvement of the corneal surface at any time point. Aqueous tear production in the BTX-B-injected fluorometholone-treated group started to return to baseline level within 2 weeks, although not significantly. Meanwhile, BTX-B-injected mice treated with artificial tears, topical NSAIDs, and doxycycline still exhibited a reduction in tear production up to 4 weeks. No significant differences in blink rate between the control and study groups undergoing the various treatments were noted at all time points. CONCLUSIONS: This study suggests the potential usefulness of topical NSAIDs, corticosteroid, and doxycycline for the clinical treatment of ocular surface epithelial disorders associated with dry eye.

Orbital apex syndrome from gnathostomiasis.

A 16-year-old Thai girl presented with acute unilateral visual loss, proptosis, and ophthalmoparesis. CT demonstrated thickening and enhancement of orbital tissues including the orbital apex. A history of consumption of raw fish, together with the findings of cutaneous migratory swelling and eosinophilia, made the diagnosis of gnathostomiasis likely. Her serum was positive for Gnathostoma spinigerum using an immunoblotting technique. Parasites removed from the skin lesions revealed the typical head bulbs with 4 circumferential rows of hooklets and fine cuticular spines on their surface. Treatment with an antihelminthic and systemic corticosteroids led to resolution of orbital inflammation but left a persistent optic neuropathy marked by nerve fiber bundle visual field loss with normal visual acuity. Gnathostomiasis should be suspected in patients with an orbital apex syndrome who live or travel in an endemic area, have eaten raw fish, and develop a migratory skin rash.

Four recti enlargement at orbital apex and thyroid associated optic neuropathy.

OBJECTIVE: To determine the site of muscle enlargement in thyroid-associated ophthalmopathy and optic neuropathy in Ramathibodi Hospital. MATERIAL AND METHOD: Data and images of MRI and CT of patients with thyroid-associated ophthalmopathy were retrospectively reviewed Neuro-ophthalmologic data and correlation to the imaging findings were analyzed. RESULTS: Among 19 patients with thyroid-associated ophthalmopathy, 20 imaging studies were collected. There were 4 patients with bilateral disease and crowdedness of 4 recti muscle. All of them had thyroid associated optic neuropathy. One out of 19 patients underwent two different sessions study. During her first study, right optic nerve was involved with the crowding of right optic nerve but 7 months later her left optic nerve became involved with crowding of the left optic nerve and the right 4 recti appeared smaller CONCLUSION: Four recti muscle enlargement in thyroid-associated ophthalmopathy, like four-leaf clover in coronal section of imaging study, may be an important sign of thyroid associated optic neuropathy.

Reconstruction of contracted eye socket with amniotic membrane graft.

PURPOSE: To investigate the use of amniotic membrane graft for socket reconstruction in cases in which forniceal shortening by scar or symblepharon formation has made it difficult to successfully wear an ocular prosthesis. METHODS: A retrospective analysis of 20 contracted eye sockets that underwent forniceal reconstruction with amniotic membrane graft from 1997 to 2001. RESULTS: There were 8 male and 12 female patients, with an age range between 2 and 66 years. Duration of forniceal shortening varied from 2 months to 48 years. The operation was performed in the lower fornix in 13 eyes, upper fornix in 1 eye, and both fornices in 6 eyes. The mean follow-up period was 13.6 months. Eighty percent of cases achieved successful prosthetic fitting after surgery. Four eyes had recurrent forniceal shortening after surgery in which a prosthesis could not be properly fitted. There were no serious complications, such as infection or graft rejection. CONCLUSIONS: The use of amniotic membrane grafts can be a useful option in forniceal reconstruction with a high success rate, a low rate of complications, and without discomfort of donor sites.

Retrobulbar injection of triamcinolone in thyroid associated orbitopathy.

OBJECTIVE: To identify the result of retrobulbar triamcinolone injection in patients with thyroid associated orbitopathy MATERIAL AND METHOD: Prospective noncomparative pilot study in 27 eyes of 19 patients who had been diagnosed as thyroid associated orbitopathy during October 2000 through April 2002. The patients received retrobulbar 40 mg triamcinolone treatment for each orbit weekly, totaling 4 applications. RESULTS: Three months after treatment, most of the patients demonstrated no significant change in visual acuity and visual field. Improvement of proptosis was observed in 15 eyes (56%) and stable in 10 eyes (37%). Seven patients (41%) had improvement of extraocular muscle function as demonstrated by Hess test. These results remained stable in the majority of patients at the 6 months follow up period. No systemic side effects were observed The only significant local side-effect was intraocular pressure elevation which was found in 8 eyes and responded to antiglaucoma therapy. CONCLUSION: This preliminary study demonstrated the potential benefit of retrobulbar triamcinolone injection in cases of thyroid associated orbitopathy. Long-term study in these patients is required.

Aneurysmal third nerve palsy.

To study the clinical characteristics, treatment and outcome of patients with aneurysmal third nerve palsy. Eleven patients with isolated third nerve palsy from an intracranial aneurysm from 1998 to 2002 at Ramathibodi Hospital were reviewed retrospectively. The average age was 60 years. Ipsilateral headache and/or retroorbital pain occured in 80 percent of the patients. Ten patients had unilateral disease, whereas one patient had bilateral involvement. The most common site of aneurysm was at the origin of the posterior communicating artery. Endovascular treatment with coil embolization provided successful occlusion as well as neurosurgical clipping. Recovery of third nerve function was found in all patients but had variable degrees. Patients who received early treatment, especially within 10 days after onset of oculomotor dysfunction appeared to have the best chance of recovery. Aberrant regeneration developed in 5 cases. The commonest sign was lid retraction during adduction and downward gaze.