Endothelial cell loss gradual, levels off after ICL implantation

October 15, 2004

San Diego-Implantation of the Implantable Contact Lens (ICL, STAAR Surgical) to treat myopia has a negligible effect on the corneal endothelium 3 to 4 years after implantation of the lens, according to Henry Edelhauser, PhD.

Images were obtained from 12 investigators from 12 clinical sites, then analyzed in masked fashion by one reader at the Specular Microscopy Reading Center. More than 1,300 images were scanned and analyzed with Konan KSS-300 software (Konan Medical Corp.). A mean of 93 cells was analyzed per image, Dr. Edelhauser said. Data were printed and underwent statistical analysis at STAAR Surgical.

Precise readings are an important factor in analyzing the endothelium, he said.

He and his colleagues analyzed the images for endothelial cell density, percent hexagonality, pleomorphism, and coefficient of variation. Stressed corneas have a percent hexagonality that is less than 45 and a coefficient of variation that is greater than 45, he pointed out.

The results of the analysis of the ICL data were very promising.

Studies conducted by other investigators and those done by Dr. Edelhauser and colleagues have shown morphology is one of the best indicators of corneal endothelial stress or instability. The measured corneal percent hexagonality over the 4 years was stable at 56% to 57% at all time points measured after the ICL was implanted.