Individuals with chronic hepatitis C being treated with Interferon ( IFN ) are at risk of developing retinopathy as early as two weeks into treatment according to the results of a study published in the Investigative Ophthalmology & Visual Science ( IOVS ).
Researchers at Asahikawa Medical College in Japan measured the changes in vessel diameter and blood velocity and calculated retinal blood flow ( RBF ) and wall shear rate ( WSR ) using a laser Doppler velocimetry in 36 patients with chronic hepatitis C who were treated with high-dose Interferon.
Sixty-one percent of these patients developed asymptomatic retinopathy, including retinal hemorrhage and cotton-wool spots, during treatment. Retinopathy was first diagnosed two to 16 weeks after the start of treatment and resolved at the end of treatment in all but nine patients.
Of these patients, all experienced an increase in blood velocity, retinal blood flow, and wall shear rate.
The increased retinal blood flow was associated with anemia induced by Interferon treatment.
The increase in wall shear rate in patients with retinopathy especially indicates that endothelial dysfunction may play an important role in Interferon-induced retinopathy as shear stress should be constant under physiologic conditions.
Source: Association for Research in Vision and Ophthalmology, 2007