Background and objective: To determine, using autopsy eyes, whether diode laser energy adjustments are indicated in patients with thin sclera.
Materials and methods: In the laboratory, the superior 180 degrees of sclera at the limbus was dissected to the level of barely visible anterior uvea and the opposite 180 degrees of sclera served as the control in three human cadaver eyes. A contact G-probe was placed at the limbus, and settings of a diode laser were increased in increments from 1.0 to 9.0 J at 4 burns per setting in each location.
Results: On gross examination, circular hypopigmented lesions were seen in the ciliary body (CB) beginning at 3.0 J in thin sclera and at 5.0 J in normal sclera. On light microscopic examination of thin scleral sections, CB damage began at 2.9 J and CB/ciliary body epithelium (CBE) damage occurred beginning at 3.5 J. In normal sclera, minimal CB/CBE changes occurred at 6.0 to 7.5 J. No scleral damage was visible in either the experimental or the control groups.
Conclusion: Cycloablation energy adjustments are indicated on eyes with abnormally thin sclera to achieve similar histologic end points using the diode laser.