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[Serious loss of vision in bilateral anterior ischemic optic neuropathy caused by interferon].

BACKGROUND
We treated a patient with anterior ischemic optic neuropathy caused by peginterferon.


CASE
Upon medical examination of the eyes before starting interferon therapy for chronic hepatitis C at Saiseikai Izuo hospital, a 64-year-old man showed corrected visual acuity of 0.9 in the right eye and 1.0 in the left. No abnormality was visible in either eye except for mild cataracts. Six weeks after combination therapy with peginterferon alpha-2b and ribavirin was started, corrected visual acuity was found to have decreased in the right eye, and swelling of the optic nervehead in both eyes was evident. Bilateral anterior ischemic optic neuropathy caused by interferon therapy was diagnosed. Combination therapy with peginterferon alpha-2 b and ribavirin was discontinued, and administration of prednisolone was started at a dose of 60 mg. However, visual acuity declined in both eyes and the visual field defects worsend. At the most recent examination, visual acuity was 1.0 in the right eye and 0.01 in the left. The visual field included only the temporal periphery in the left eye, and part of the central and upper temporal periphery in the right.


CONCLUSION
Since the outcome of visual acuity and visual fields in anterior ischemic optic neuropathy caused by interferon can be poor, an effective therapy for this complication needs to be developed.