Interphotoreceptor Retinoid-Binding Protein Levels in Subretinal Fluid From Rhegmatogenous Retinal Detachment and Retinopathy of Prematurity

• Interphotoreceptor retinoid-binding protein (IRBP) has been detected qualitatively in subretinal fluid associated with rhegmatogenous retinal detachments. We have used a quantitative enzyme-linked immunosorbent assay to determine the IRBP concentrations in 24 fluid specimens collected at retinal reattachment surgery from 22 patients, and from 17 patients who underwent surgery for retinopathy of prematurity with traction detachment. We observed a wide range of concentrations (1 to 176 μg of IRBP per milligram of protein). Higher concentrations were found only in fluid from the more recent rhegmatogenous detachments. The lowest concentrations were detected among fluids drained from under rhegmatogenous detachments ranging from five days' to one year's duration. The IRBP concentration in subretinal fluid showed no correlation with visual outcome and may be influenced by IRBP turnover in the vitreous cavity. Most strikingly, none of the 17 samples from patients with retinopathy of prematurity contained detectable amounts of IRBP.