Purpose:

Systemic administration of isotretinoin, one of the synthetic retinoids having effect on cell growth and differentiation, might have side effects on different systems. In this study, we aimed to evaluate optic nerve functions in patients treated with oral isotretinoin both clinically and with visual field tests.

Material and Method:

Fourteen patients planned to be treated with oral isotretinoin for nodulocystic acne were enrolled in this study. All patients underwent a complete ophthalmologic examination and an automated threshold perimetry with Humphrey 30.2 test for visual field assessment. Patients with normal findings at initial examination were prescribed 0.5-1 mg/kg oral isotretinoin and all examinations were repeated before cessation of the treatment.

Results:

Nine female and 5 male patients had a mean age of 22.07±3.5 years. The dose of oral isotretinoin was 1 mg/kg/day for 3 patients and 0.5 mg/kg/day for 11 patients, which was continued for 5.5±1.34 months. All patients had a best corrected visual acuity of 10/10, and direct and indirect light reflexes, color vision tests with Ishihara plates, anterior and posterior segment findings were normal at both the initial and follow-up examinations. Although mean deviation (MD) and pattern standard deviation (PSD) values did not show any difference in the first and last visual field tests, in pattern deviation probability maps, the probability points <%2 and <%1 had a statistically significant decrease at the end of the treatment.

Discussion:

Side effects as decreased dark adaptation, pseudotumor cerebri, optic nerve edema, and headache indicate that systemic isotretinoin treatment may cause neurotoxicity. In this study, we did not find any adverse effects of systemic isotretinoin treatment on optic nerve functions and retinal ganglion cells. Nevertheless, we think that the assessment of these functions in a larger patient group and with tests like SWAP or FDT for early detection of visual field loss would be more appropriate.

Keywords: Isotretinoin, side effect, optic nerve, visual field