Immunodacryochemistry (immunoferning): a new screening method for proteins in tears.

Abstract

The ferning test of tears has been an intensively discussed method for rough but quick visualization of general tear fluid composition. Regarded as crystallization process resulting from simple water subtraction (Battaglia and Giusto 1993), it has useful features, amongst them the minimal equipment required, but standardization is a known problem. The classification according to Rolando (1984) seems to significantly increase the clinical applicability of this technique (Pensyl and Dillehay 1998). Even though the ferning test has been proposed for predicting contact lens tolerance (Ravazzoni et al. 1998), the underlying mechanisms of the ferning pattern is still not clearly understood (Kogbe et al. 1991). Recently, it has been evaluated as a method to develop a rough picture of the crystallization process, reflecting the qualitative composition of tears (Sommer et al. 1994). The accuracy of the method, however, in clinical conditions such as dry eyes seems to be inferior to impression cytology (Jackson and Perrigin 1999), but it may show clear pathological changes (Norn 1994, Vaikoussis et al. 1994, Maragou et al. 1996). Today, with the current means of interpretation, the ferning test is seen as a practical, quick, easy and reliable complement to other tests (Albach et al. 1994). In the present study we develop a further use of the ferning procedure.