Quantitative analysis of protein deposits on hydrophilic soft contact lenses: I. Comparison to visual methods of analysis. II. Deposit variation among FDA lens material groups.

Patient-worn lenses (N = 1058) were evaluated using both the Rudko method for deposit typing and a quantitative assay for adsorbed protein. The visible deposit typing results were compared to the values obtained by the quantitative assay. The Rudko method for deposit classification was found to be a poor quantitative measure of deposited protein. Statistical differences were found between protein levels on lenses with identical Rudko scores among the FDA lens groups. In many cases, no meaningful correlation was found between Rudko scores and protein levels for lenses within the same FDA lens group. Significant differences in the distribution of visible deposits (Rudko scores) were found among the four FDA lens groups. Significant differences were also found in the quantity of adsorbed protein among FDA lens groups.