A case of prolonged corneal edema developed after xenon arc retinal photocoagulation. Heat absorption by the anterior segment is thought to be the main cause of endothelial damage and consequent stromal edema. Iris overlap by the light beam, high intensity energy, and cataract seem to be favorable conditions for aqueous and corneal overheating. The contact lens used during photocoagulation may have aggravated heat retention by insulating the cornea from its normally cooler environs. Caution is warranted when several of the factors favoring heat absorption by the anterior segment are present.
Pfister RR, Schepens CL, Lemp MA, Webster RG. Photocoagulation KeratopathyReport of a Case. Arch Ophthalmol. 1971;86(1):94-96. doi:10.1001/archopht.1971.01000010096018