Significant loss in corneal endothelial cells reported after implantation of glaucoma valve

Am J Ophthalmol. 2009;148(3):361-367.

While endothelial cell loss overall was significant in eyes implanted with a glaucoma valve, the area closest to the tube had the most significant loss of endothelial cell density, a study found.

"The supratemporal area, the closest site to the tube, showed the greatest decrease in endothelial cell density, by 22.6%, whereas the central cornea showed the smallest decrease, by 15.4%, at 24 months after surgery," the study authors said.

The study, an observational case series, had 41 refractory glaucoma eyes that were evaluated for change in density and shape of the corneal endothelium after Ahmed glaucoma valve (New World Medical) implantation. Results from those eyes were compared with a control group of 20 contralateral glaucomatous eyes.

Mean follow-up in the study was 19.1 months.

The researchers used corneal specular microscopy to obtain results from the superior, supratemporal, supranasal and central areas at 1, 6, 12, 18 and 24 months postoperatively.

According to the study, corneal endothelial cell count decreased by 5.8% at 1 month postop, 11.5% at 6 months, 15.3% at 12 months, 16.6% at 18 months and 18.6% at 24 months. All differences were statistically significant from baseline and from the control eyes.