a Phase II Double Blind, Randomized, Placebo Controlled Trial of Effect of Phenytoin on the Ganglion Cell Inner Plexiform Layer (GCIPL) Thickness and Visual Field in Patients With a First Episode of Acute Optic Neuritis
Phase: PHASE2
Conditions: Optic Neuritis
Sponsor: Tehran University of Medical Sciences

Effect of Phenytoin on the Ganglion Cell Layer in Patients 
with Optic Neuritis 
 
NCT02939937 
4/14/2019 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Study Protocol  
Optic neuritis is diagnosed based on the sudden loss of unilateral vision in a person aged 18- 60 with 
painful eye movements and colored vision impairment, as well as pupil defects and associated visual 
impairment (confirmed by neuro-ophthalmologist). Patients entered It should be kept alert to another 
eye plan. There is also no primary pathology in Oct. The control group was selected as cohort and dual 
blind randomized. 108 patients referred to Farabi Hospital during the years 2016 to 2018 were 
diagnosed with optic neuritis in a one-to-one treatment with 300 mg daily for Phenytoin and placebo at 
the first 14 days after Detect Optic Neuritis. All patients are treated for corticosteroids for an acute 
phase with a 1 g daily intravenous methylprednisolone daily for 3-5 days. EXCLUSION CRITERIA Previous 
history of optic neuritis in the contralateral eye-recurrence in the same eye-Eye disease that affects the 
study at the same time - Clinical hepatitis or proven laboratory testsDisorders of the kidney or heart 
function (such as disturbed electrocardiogram) - Contraindication of Phenytoin intake (such as 
pregnancy) Or previous sensitivity to Phenytoin ) - Using sodium or calcium channel blockers over two 
weeks before starting Phenytoin and receiving other immunosuppressive drugs during the 2 months 
prior to treatment - IOP greater than 21 - Refractive error greater than 5 diopters The initial examination 
consists of the best corrected visual acuity , applanation tonometry, slit examination and funduscopy. 
Best corrected visual acuity is converted to logMAR (logarithms of minimum angle of resolution) by 
statistical calculation. In all patients, the visual field is performed by the Swedish interactive 
thresholding algorithm standard 24-2 perimeter (Carl Zeiss mediated, Dublin, California). The false 
positives are less than 13%, the false negative are less than 30% acceptable. The light sensitivity in the 
visual field is measured by the decibel (db). All patients have Optical Coherence Tomography. The 
thickness of RNFL and MACULA and GCIPL are evaluated in 8 sectors:these stages in the first and sixth 
month after the onset of the disease It repeats itself. Then, the relationship of values obtained in 
macular thicknesses and GCIPLs with VF is compared at different times. Data are analyzed by SPSS 
version 20 software.