Temperature Chanaes of Ocular Tissues by Scleral Surface Diathermy

ABSTRACT

Tissue temperatures were measured by a thermistor-thermometer, at suprachoroid, inner retinal surface and intravitreous portion (1mm deep), during diathermy applications on the scleral surfaces of rabbit eyes. Castroviejo's Electro-surgical Ophthalmic unit Model S-5 was used and power intensity(current) was fixed to 2, and diathermy was applied on the sclera 3mm, 2mm, and 1mm from and above the measuring points. Measurements were performed in the following groups Group 1 Spark gap power 2. duration of application 2 sec. Group 2 Spark gap power 2. duration of application 3 sec. Group 3 Spark gap power 3. duration of application 2 sec. Group 4 Spark gap power 3. duration of application 3 sec. Maximum rise of temperature was 20.0 degrees C at suprachoroid, 16.8 degrees C at inner retinal surface and 6.6 degrees C at vitreous in Group 4. Temperature rise in vitreous was much lower than that in suprachoroid and inner retinal surface (table II, which revealed percentage of average rise per tissue temperature before diathermy). Highest measuring temperature at inner retinal surface in this experiment was under 60 degrees C, at which vitreous collagen fibrils may coagulate.