Vol. 7, Issue 1, Part A (2025)

Background: The prevalence of tuberculosis remains high, while standard Anti-TB Therapy (ATT) leads to toxic optic neuropathy and multiple adverse effects in the eyes. The implementation of color-vision testing and perimetry, and OCT examinations during the early stages helps prevent unnecessary vision damage.
Objective: The study aims to establish the occurrence rates and specific patterns of optic neuropathy and other eye-related complications that occur during ATT treatment for newly diagnosed TB patients.
Methodology: The study included 80 pulmonary TB patients receiving standard HRZE treatment who were under routine ocular examination and follow up at Vision Eye Hospital in Dhaka from January 2022 through December 2024. The study included BCVA (Snellen) and color vision (Ishihara) tests, along with slit-lamp bio-microscopy and indirect ophthalmoscopy, HVF 30-2 perimetry, and OCT to measure RNFL thickness. The researchers used MS Excel and SPSS v25 to analyze data collected from case-report forms while setting a 0.05 significance level. The researchers conducted follow-up evaluations of patients after they started ATT treatment at both the 3-month and 6-month marks.
Results: The study enrolled 46 males and 34 females (male to female ratio 1.4:1) whose ages spanned from 18 to 65 years (mean 36.8±12.4), with the majority falling between 18 and 30 years old. The initial examination revealed 154 out of 160 eyes (96.3%) had 20/20 visual acuity, while 6 out of 160 eyes (3.7%) showed 20/30 to 20/60 vision. The visual acuity results at 3 months showed 150/160 (93.8%) eyes at 20/20 and 8/160 (5.0%) at 20/30-20/60 and 2/160 (1.2%) at 20/70-20/200. The results at 6 months showed 146/160 (91.3%) eyes with 20/20 vision and 10/160 (6.2%) with 20/30-20/60 vision, and 4/160 (2.5%) with 20/70-20/200 vision, with no eyes below 20/200 at any point. The initial examination revealed no dyschromatopsia, but 4 out of 160 eyes (2 red-green and 2 blue-yellow) developed this condition at 3 months, and 12 out of 160 eyes (6 red-green and 6 blue-yellow) at 6 months. The visual field tests revealed 2 eyes with defects at 3 months and 8 eyes at 6 months (total 10/160; 6.3%), with cecocentral scotoma being the most common defect (6/160; 3.8%), followed by peripheral constriction (3/160; 1.9%) and bitemporal hemianopia (1/160; 0.6%). The OCT RNFL (μm) measurements demonstrated the following changes from baseline to 6 months: superior 124.5±12.6→122.1±13.8 (P=0.08), inferior 126.8±11.9→124.6±12.4 (P=0.12), nasal 96.3±9.8→95.2±10.2 (P=0.21), temporal 74.2±8.1→69.8±7.9 (P=0.002), and average 105.5±10.4→103.0±11.2 (P=0.04).
Conclusion: ATT-related ocular toxicity is unusual but detectable within 6 months, affecting mainly color vision, visual fields, and temporal RNFL. Regular eye screening during TB treatment is required to prevent irreversible visual loss.