Beena R.1, Anuradha T.R.2
BACKGROUND
Relative afferent pupillary defect (RAPD) or Marcus Gunn pupil is a highly sensitive
and significant objective clinical finding in eye examination. It can be detected by
swinging flashlight test. Its presence indicates unilateral afferent sensory
abnormality or an asymmetric bilateral disease. However, it can be determined
even in an unconscious patient, requires no complicated gadgets, relies on clinical
observation but can be a manifestation of a myriad of disorders affecting the eye
or the brain. The goal of our study was to identify the aetiology of relative afferent
pupillary defect and ascertain whether the grade of relative afferent pupillary
defect correlated with the visual prognosis.
METHODS
This was a prospective observational hospital-based study. 25 consecutive patients
who presented with a clinical diagnosis of relative afferent pupillary defect to the
Ophthalmology Department of Kanyakumari Government Medical College in Tamil
Nadu from February 2019 to January 2021 were included in the study. The patients
were evaluated based on visual acuity, refraction, colour vision, slit lamp, fundus
examination, intra ocular pressure (IOP) measurements & fields. Statistical
analysis was done by trial version of statistical package for social sciences (SSPS)
software.
RESULTS
Of the 25 cases analysed, 60 % (15) were male, 36 % (9) were females and 4 %
(1) children. An analysis of the aetiology revealed that the optic nerve pathology
was the predominant aetiology accounting for 60 % (15) of cases, followed by
glaucoma 24 % (6) and retinal pathology in 16 % (4). Glaucoma though a bilateral
disease has an asymmetrical presentation which led to RAPD. Grade of RAPD
correlated well with the visual prognosis.
CONCLUSIONS
RAPD is a good and valuable clinical tool for any clinician, it is also a useful guide
for assessing the management and response to treatment.
