This report is concerned with oral glycerin as a hypotensive agent in cataract surgery. The advantages of operating on a soft eye are unquestioned. The first approach to surgical hypotonia, digital pressure1,2 following retrobulbar anesthesia, has now achieved wide acceptance. Osmotic agents, however, have been more recently advocated. Urea and later mannitol3-10 have been used with benefit. The main disadvantage of these agents has been that infiltration at the injection site may be complicated by a severe tissue slough. Other problems have been the availability of trained technical assistants to administer intravenous solutions, transportation to the operating room, and the necessity for continuous observation of the injection site during surgery. There have also been reports of serious toxic reactions to these agents. Furthermore, they cannot be given orally since urea exerts profound emetic and purgative effects, while mannitol is ineffective due to failure of intestinal absorption.
JAFFE NS, LIGHT DS. Oral Glycerin in Cataract Surgery. Arch Ophthalmol. 1965;73(4):516-518. doi:10.1001/archopht.1965.00970030518014