A prospective study of change in visual function in patients treated with pegylated interferon alpha for hepatitis C...

Hepatitis C virus and interferon treatment have been associated with retinopathy. Baseline and ongoing assessment by ophthalmologists have therefore been advocated in previous studies. Our experience suggests that the incidence is low, with no or negligible impact of pegylated interferon alpha on actual visual function. This study was conducted to determine whether ophthalmic assessment is necessary in such patients.

The study was a prospective case series of 52 patients (104 eyes). Visual acuity, contrast sensitivity, colour vision, visual field by perimetry and fundal assessment were measured at baseline and at 3 and 6 months post commencement of interferon alpha treatment.

Forty-two men and ten women were followed. No patients reported any subjective visual symptoms. The mean changes in right and left logarithmic minimal angle resolution (LogMAR) visual acuity were negligible between baseline and 6 months (0.05 (SD 0.13) and 0.10 (SD 0.12), respectively). Mean changes in contrast sensitivity and colour vision were also negligible. Of all eyes monitored by serial perimetry for the full follow-up period and deemed to have reliable tests, none developed visual field defects. One patient appeared to develop nasal field defects within 3 months of commencing treatment but failed to attend for repeat testing. No patients developed optic disc changes or permanent fundal changes over the follow-up period.

In contrast to previous studies in America and south-east Asia, our findings based on a UK cohort suggest that routine ophthalmic screening is not essential for patients with hepatitis C treated with pegylated interferon alpha who have no subjective visual complaints.