Purpose
Corneal specular microscopes project light onto the cornea and use reflected light to show a magnified image of the endothelium. The NIDEK CEM-530 is a novel optical specular microscope used for obtaining a ocular measurements such as endothelial cell density measurements (CD), coefficient of variation of endothelial cell area (CV), and percent hexagonality (6a). The purpose of this study was to assess the agreement of the measurements of CD, CV, and percent 6a between the NIDEK CEM-530 and the CELLCHEK XL predicate device, and to assess the precision of the two instruments with respect to these measurements.
Methods
This prospective study enrolled 78 subjects in the study, 24 in the non pathologic young eye population, 26 in the non pathologic adult eye population, and 28 in the pathologic adult eye population. Of those, 74 and 62 subjects were included in the effectiveness and precision analyses, respectively. Measurements were acquired to capture the clinical data points for CD, CV, and percent 6a each device.
Results
The mean differences were generally small relative to the mean values for each endpoint (Table 1). The differences were on the order of 3-5 percent of the overall mean value for endothelial cell density, coefficient of variation of endothelial cell area, and approximately 15 percent of the overall mean for percent hexagonality. The repeatability and reproducibility components for the CEM-530 machine were similar to or smaller than those of the CELLCHECK XL (Table 2).
Conclusions
The results of this study show that the NIDEK CEM-530 may be a viable and superior alternative methodology as compared to currently available technology.
Keywords: 481 cornea: endothelium •
552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
550 imaging/image analysis: clinical