Light coagulation with indirect ophthalmoscopy.

Abstract

Chorioretinal burns due to exposure of the retina to direct sunlight have been recognized for many years as the cause of eclipse blindness. In 1916, Verhoeff and Bell analyzed the physical principles of this phenomenon and performed animal experiments wherein they were able to produce such burns.¹In 1949, Meyer-Schwickerath used sunlight to cause chorioretinal burns to close retinal tears.²However, because of difficulties resulting from inclement weather and seasonal changes in the light intensity of the sun, he was prompted to devise a carbon-arc source of light, with a brightness of 100,000 to 200,000 stilb, for producing chorioretinal burns.^3,4This instrument utilizes a direct ophthalmoscopy principle in order that the operator may observe the fundus during application of the high-intensity light. Meyer-Schwickerath has used this technique successfully in the treatment of posterior fundus lesions, such as macular holes, tumors, and new-formed vessels. In addition, he has