Intraocular pressure reduction and vitreous mass: Influence of retrobulbar anaesthesia and acetazolamide.

Recent studies have evaluated many methods of reducing vitreous mass and minimizing vitreous loss at lens extraction (Robbins and Galin, I969; Robbins, Blumenthal, and Galin, I970; Galin, Robbins, and Obstbaum, 1970). In the rabbit, it is clear that hyperosmolar solutions are effective, while digital massage is not (Obstbaum, Robbins, Best, and Galin, 1970). It has been accepted that correctly-induced retrobulbar anaesthesia also reduces the risk of vitreous extrusion (Gartner, 1959; I96I). It is assumed that the loss of muscle tone prevents retraction of the globe and scleral shell, but any other direct or indirect effect of the anaesthetic on the vitreous mass has not hitherto been investigated. Another common preoperative procedure is the use of acetazolamide (Gartner, I959; Agarwal, Gupta, and Malik, I959), but there have been no clinical or laboratory studies of the effect of this drug on the vitreous. The present communication reports the results of a study of the effect of retrobulbar anaesthesia and acetazolamide on the vitreous mass in rabbit eyes.