Computerized densitometric measurement system (CDMS) for the quantitative analysis of diffuse retinal nerve fiber layer atrophy

Abstract

Since observable retinal nerve fiber layer (RNFL) atrophy occures several years before irreversible glaucomatous visual field damage in glaucoma patients, quantitative assessment of the diffuse RNFL atrophy has been the goal of many research efforts. The loss of RNFL reflectance is informative sign of the diffuse RNFL atrophy, and appears in monochrome photograph of RNFL. We have, therefore, made a system by which we could measure the loss of RNFL reflectance and named it Computerized Densitometric Measurement System (CDMS). In this method, density profiles concentric with optical disc are extracted from the digitalized RNFL photograph. Density integral of superior and inferior segments in the density profile is used for the assessment of RNFL atrophy. Satisfactory results were obtained about the clinical utility of this method when the CDMS measurement was compared with the indicator of loss of visual function. Intra- and inter-operator reproducibility was also excellent.