Changes of the corneal endothelium following intracapsular cataract extraction with implantation of semiflexible anterior chamber lenses. I. Results of the early post-operative period

Experimental evaluation of a phakic anterior chamber implant in a primate model. Part I. Clinical observations

Anterior chamber intraocular lenses were implanted in phakic cynomolgus monkey eyes and followed clinically over two years. Significant observations included erosion and/or uveal envelopment of the haptic and a decrease in endothelial cell counts. There was good positional stability, no significant inflammation, initial ocular hypotension that returned to normal intraocular pressure, and no evidence of cataracts or cystoid macular edema.

Complications of anterior chamber lens implants and their effects on the endothelium

A five-year follow-up study of 186 eyes which were subject to intracapsular cataract extraction and rigid anterior chamber lens implantation is reported. Ninety-two per cent of cases achieved a visual acuity of 6/12 or better. Serial corneal endothelial cell counts were performed. In 37 pairs of eyes the median difference in operative endothelial cell loss between the operated and un-operated eyes was -7.3% (95% Confidence Interval from -8.7 to -6.1%). Iris tuck occurred in 22.0% and late 'iris ovalling' developed in a further 15.6% of eyes. The median operative endothelial cell loss for those eyes with iris tuck was -9.7% and this was significantly higher than that of eyes with no long-term complications (median loss = -7.3%). The median operative endothelial cell loss for those eyes which developed late ovalling was -8.0% and this was not significantly greater than that of the eyes with no long-term complications (p = 0.745). There was a progressive median endothelial cell loss for all operated eyes and this progressive cell loss was significantly greater for those eyes with iris tuck when compared with those with no complications (p = 0.045).

Comparison of the effect of polymethylmethacrylate and silicone intraocular lenses on rabbit corneal endothelium in vitro

An in vitro comparison of corneal endothelial damage caused by polymethylmethacrylate and by silicone intraocular lenses was made. Endothelial damage was assessed by vital staining of corneal endothelium immediately following direct contact with an intraocular lens. Silicone lenses produced less damage than polymethylmethacrylate lenses. The difference could be attributed to a specific type of damage-membrane stripping-seen only after contact with polymethylmethacrylate lenses.