Microperimetry in Optic Neuritis
Optic neuritis negatively impacts various visual functions including visual fields.
Varying patterns of field loss have been reported, ranging from altitudinal,
arcuate and centrocaecal to diffuse and even unilateral hemianopic field defects.
Nearly all studies on visual fields in optic neuritis have been done using the standard
automated perimetry, which has inadequate compensation for eye movements and
this is particularly important in cases of poor vision and central scotomas
such as those seen in optic neuritis.
Microperimetry is a novel diagnostic modality that overcomes
this limitation by continuously tracking the patient’s fundus during stimulus projection.
Eye movement detected by the machine either causes a pause in stimulus projection,
or alteration the position of stimulus projection to match the amount of eye excursion.
Additionally, the microperimeter also overlays the sensitivity map
on the fundus image providing a visually appealing result with good structural correlation.
This study evaluates microperimetry as tool for visual field assessment
in optic neuritis and compares it with the standard automated perimetry.
A prospective case control study was conducted at a tertiary eye
care hospital in India after prior approval from the Institutional Ethics Committee.
The inclusion criteria for cases was the presence of acute unilateral optic
neuritis diagnosed clinically in the absence of any other ocular or neurological
pathology likely to affect fields.
Visual acuity in clinically affected eyes was found to be significantly
lower than fellow eyes and controls.
It improved incompletely over 1 month and needed a period of 3 months to
reach normal levels, similar to the control group.
Ophthalmol Open J. 2016; 1(1): 21-28. doi: 10.17140/OOJ-1-106