Scleral damage: comparison of standard and modified diathermy electrodes.

Full-thickness scleral diathermy using a standard electrode causes significant scleral damage and necrosis. Use of a modified (Jabbour's) diathermy electrode appears to cause minimal scleral damage. We evaluated the scleral changes following transscleral diathermy application using standard and modified diathermy electrodes to the peripheral retina and ciliary body. Twelve Dutch belted pigment rabbits were used in our experiment. Three eyes each were subjected to transscleral diathermy using standard and modified electrodes to produce chorioretinal scars and cyclodestruction. Eyes were examined with the slit lamp and indirect ophthalmoscope at weekly intervals for 4 weeks. Light and transmission electron microscopy was performed 1 hour after diathermy application in 4 animals and in the remaining 8 animals at 4 weeks. Chorioretinal scarring and ciliary body atrophy were successfully induced with both types of electrodes. However, scleral damage was less severe in eyes treated with the modified electrode as compared with the standard electrode.