Abstract
Purpose::
Fuchs corneal dystrophy (FCD) is characterized by the development of guttae on Descemet's membrane. Guttae influence the passage of light through the cornea as evidenced in retroillumination photographs. The purpose of this study was to determine if corneal light scattering increases in Fuchs patients.
Methods::
Patients for this study were recruited from the extended family described by Sundin et al [IOVS, 47, 140-145, (2006)]. All procedures were approved by the IRB at Johns Hopkins School of Medicine and are in accordance with the Declaration of Helsinki. Pupils were dilated and objective light scattering measurements were made with a scatterometer as described by McCally et al[IOVS, 47, 4288-4294,(2006)]. A scattering index (SI) was calculated as the ratio of the normalized scattering to the average scattering from the normal corneas of 12 individuals. SI = 1 represents normal scattering. Retroillumination photographs were obtained to document guttae.
Results::
Scattering data and retroillumination photographs were obtained from both eyes of 32 patients. SI values ranged from 0.92 to 3.25 OD and from 0.88 to 2.90 OS. High SI values were generally associated with areas of confluent guttae. Low SI values were generally associated with absence of disease (very few or no guttae) or with non-confluent guttae. A few exceptions were noted for both high and low SI values. These may be associated with the fact that the scatterometer measures scattering only from a central 2 mm diameter region or from variations in corneal thickness.
Conclusions::
Light scattering provides an objective measure of the severity of FCD as indicated by the appearance of guttae in retroillumination photographs. Future studies may demonstrate a correlation of light scattering with decreased vision and subjective complaints such as glare in FCD patients.
Keywords: cornea: endothelium • cornea: basic science