Ethambutol toxicity: Expert panel consensus for the primary prevention, diagnosis and management of ethambutol-induced optic neuropathy.

Ethambutol use may lead to permanent vision loss by inducing a dose- and duration-dependent optic neuropathy. This has been of concern to ophthalmologists and physicians both; however, ethambutol continues to be used because of its anti-mycobacterial action with relative systemic safety. Recently, the guidelines of the Revised National Tuberculosis Control Programme of India have been revised to allow for fixed dose and longer duration of ethambutol use; this is likely to result in an increase in vision-threatening adverse effects.

Ethambutol Optic Neuropathy: Vigilance and Screening, the Keys to Prevent Blindness with the Revised Anti-tuberculous Therapy Regimen.

There has been change in the guidelines for the management of tuberculosis in India. The new guidelines advocate the daily use of Ethambutol for both intensive and continuation phase of the treatment. This may be a matter of concern as increased cumulative dose may lead to increase in incidence of toxic optic neuropathy due to ethambutol.

Spectacle Coverage among Urban Schoolchildren with Refractive Error Provided Subsidized Spectacles in North India.

Significance: Provision of subsidized spectacles to schoolchildren with refractive error in Delhi was associated with increased spectacle coverage.

Purpose: Studies involving free spectacle distribution and self-purchase of spectacles often report poor compliance. We assessed 1-year spectacle coverage among schoolchildren with refractive error who were provided subsidized spectacles.

Steroids versus No Steroids in Nonarteritic Anterior Ischemic Optic Neuropathy: A Randomized Controlled Trial.

Purpose: To examine the role of oral steroid therapy in the treatment of nondiabetic cases of acute nonarteritic anterior ischemic optic neuropathy (NAAION).

Design: Randomized double-blind clinical trial.

Participants: Thirty-eight patients with acute nondiabetic NAAION divided into 2 arms of 19 patients each.

Retinal nerve fiber layer and ganglion cell layer changes on optical coherence tomography in early multiple sclerosis and optic neuritis cases.

Purpose: To study the retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) changes on optical coherence tomography in early multiple sclerosis (MS) patients.

Methods: A prospective cohort study was conducted at a tertiary care center. Patients of early MS (expanded disability status scale <3) with or without optic neuritis (ON) and idiopathic ON were included.

Evaluation of the Protective Effect of NMDA/Non-NMDA Receptor Antagonists Against Ethambutol Induced Retinal Toxicity Using ERG in Wistar Rats.

To study the protective effect of NMDA and non-NMDA receptor antagonists against ethambutol (EMB) induced retinal toxicity in Wistar rats using flash electroretinogram (ERG). Rats were randomized into four groups: Group-1 received vehicle. Group-2 received oral EMB (200 mg/kg/day).

Fabrication and Validation of Gyro-Dot-Optomotor Response Device using Gold Fish to Study Drugs Affecting Visual Perception.

An appropriate model to predict the effect of xenobiotics on the vision perception in neuropsychoharmacological studies is of great importance in drug development and toxicity studies. The present study valuated the effect of CNS stimulant, depressant and therapeutic agents known to have ocular toxicity on ptomotor response (OMR) using goldfish in a newly developed device. A digital light processing aided gyrating poly-chromatic dotted pattern-OMR (Gyro-dot-OMR) analyzer was developed and standardized for this study in our laboratory.

Correlation Between Structural and Functional Retinal Changes in Parkinson Disease.

Background: To evaluate structural changes in the retina and correlate those with visual function measurements in patients with Parkinson disease (PD).

Methods: A cross-sectional comparative study of 20 patients with PD and 20 age-matched healthy controls was conducted. Visual acuity, color vision, contrast sensitivity, visual fields, pattern visual-evoked response (VER), and multifocal electroretinogram were recorded to determine functional change, whereas structural changes were evaluated with retinal nerve fiber layer (RNFL) thickness, macular thickness, macular volume, and ganglion cell-inner plexiform layer complex (GCL-IPL) thickness using spectral domain ocular coherence tomography (SD-OCT).

Controversies in neuro-ophthalmology: steroid therapy for traumatic optic neuropathy.

Background: There is an increase in the incidence of traumatic optic neuropathy (TON) due to increasing urbanization and rapid spurt in the number of motor vehicles on the road. Despite early presentation and ease of diagnosis the visual outcomes in TON are still limited. There is also significant confusion about the timing, dose and efficacy of steroid treatment in its management.

An unusual cause of optic atrophy in a child.

A 13-year-old child presenting with gross visual impairment was diagnosed as a case of optic atrophy. However, radiological investigations revealed osteopetrosis, which, though rare, can result in optic atrophy. The aim of this case report is to highlight this possibility while evaluating cases of optic atrophy in young patients.

Clinical profile and short-term outcomes of optic neuritis patients in India.

Purpose: To evaluate the clinical profile and short-term visual outcome of optic neuritis (ON) patients in India.

Materials And Methods: In this prospective study carried out over a period of 3 years, 99 eyes of 83 ON patients were examined and followed up for 10.8 ± 8.

Evaluation of periosteal fixation of lateral rectus and partial VRT for cases of exotropic Duane retraction syndrome.

Purpose: The purpose of this study is to evaluate the lateral rectus periosteal fixation and partial vertical rectus transpositioning (VRT) as treatment modalities to correct exotropic Duane retraction syndrome (Exo-DRS).

Materials And Methods: Prospective interventional case study of cases of Exo-DRS with limitation of adduction. A total of 13 patients were subdivided into two groups.

Factors predicting recurrence in successfully treated cases of anisometropic amblyopia.

Context: Recurrence after successful treatment of amblyopia is known and understanding the risk factors could help effective management.

Aim: To measure incidence of recurrence in successfully treated cases of anisometropic amblyopia and evaluate factors predicting it.

Settings And Design: Cohort Study at a tertiary level institution.

Evaluation of changes in retinal nerve fiber layer thickness and visual functions in cases of optic neuritis and multiple sclerosis.

Context: Retinal nerve fiber layer (RNFL) thinning has been demonstrated in cases of optic neuritis (ON) and multiple sclerosis (MS) in Caucasian eyes, but no definite RNFL loss pattern or association with visual functions is known in Indian eyes.

Aim: To evaluate RNFL thickness in cases of ON and MS, and to correlate it with visual function changes in Indian patients.

Settings And Design: Cross-sectional case-control study at a tertiary level institution.

Bilateral intraocular dirofilariasis.

Ocular dirofilariasis mostly presents as a subconjunctival or eyelid lesion. Intraocular dirofilarial infestation is rare. We report a case of a young woman who was accidentally detected to have a live motile worm in the anterior segment in one eye and a cystic lesion on the optic disc in the other eye.

Evaluation of FD2 (Frisby Davis distance) stereotest in surgical management of intermittent exotropia.

Aim: To evaluate Frisby Davis distance (FD2) stereotest for determining the timing of surgical intervention in intermittent exotropia (X(T)).

Methods: A prospective case-control study was conducted including 30 patients with X(T) and 30 age-matched controls. Stereoacuity was measured preoperatively and 3 months postoperatively using FD2 for distance and TNO and Randot for near.

Is myopia a public health problem in India?

Myopia, a form of refractive error is a leading cause of visual disability throughout the world. In India uncorrected refractive errors are the most common cause of visual impairment and second major cause of avoidable blindness. Due to this the public health and economic impact of myopia is enormous.

A sphenoid sinus mucocele simulating as retro bulbar optic neuritis.

A 25-year-old male presented with complaints of sudden diminution of vision with pain on eye movement in the left eye which was diagnosed clinically as retro bulbar optic neuritis. However, magnetic resonance imaging (MRI) showed lesion consistent with sphenoid sinus mucocele. Early surgical removal of mucocele led to complete recovery of vision, contrast and visual field.

Comparing homatropine and atropine in pediatric cycloplegic refractions.

Purpose: To compare cycloplegic efficacy of homatropine and atropine in pediatric refractions and derive a regression formula to calculate refraction findings for both agents.

Methods: Children between the ages of 4 to 10 years with refractive error underwent cycloplegic refraction with 2% homatropine and 1% atropine by retinoscopy and automated refraction. Refractive data were compared by the use of power vector analysis.

Management of optic neuritis.

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.