Study of Retinal Nerve Fibre Layer Thickness and Visual Contrast Sensitivity in HIV Positive Individuals

Area of Science:

• Ophthalmology
• Retinal Imaging
• HIV Medicine

Background:

• Optical Coherence Tomography (OCT) measures Retinal Nerve Fibre Layer Thickness (RNFLT), a sensitive indicator of early retinal changes.
• HIV infection can alter RNFLT and affect visual functions like Contrast Sensitivity (CS) and visual acuity.
• Ocular pathologies in HIV can significantly impact daily life and professional activities, yet Indian studies are scarce.

Purpose of the Study:

• To investigate RNFLT, CS, and their correlation in HIV-positive individuals in India.
• To assess the prevalence of RNFLT alterations and reduced CS in this population.
• To explore the relationship between ocular parameters and CD4 count.

Main Methods:

• A cross-sectional study conducted in Eastern India involving HIV-positive subjects.
• RNFLT measured using HRA-OCT Spectralis; CS assessed via a smartphone Pellie-Robson chart.
• Visual acuity, color vision, and CD4 count were also evaluated, with data analyzed for correlations.

Main Results:

• RNFLT loss observed in 21% of eyes, with borderline thinning in 26%, predominantly in the temporal quadrant.
• 47% of eyes exhibited decreased CS (mean log CS 1.33±0.38).
• Significant correlations found between temporal RNFLT and CD4 count, and between low CS and low visual acuity.

Conclusions:

• HIV-infected individuals may experience early, subtle ocular changes affecting visual functions.
• Comprehensive eye examinations for HIV patients should include RNFLT and CS assessments.
• OCT and CS testing are valuable tools for monitoring ocular health in HIV.