Complications from use of sodium hyaluronate (Healonid) in anterior segment surgery.

Sodium hyaluronate was first used in ophthalmic surgery as a vitreous substitute more than 10 years ago' when its properties were shown to be elastic, highly viscous, yet nontoxic, noninflammatory, and nonantigenic.2 More recently Balazs, Miller, and Stegmann introduced its use into anterior segment surgery.35 The 1% solution (Pharmacia UK Ltd, Healonid) is at least 400000 times more viscous than aqueous yet will pass through the fine Rycroft cannula. It is totally transparent, and because of its high molecular weight it is nonosmotic. Because of these properties and the fact that it will maintain anterior chamber depth when air may not, it has been described as the ideal medium for closed chramber surgery.6 The particular assets of Healonid are that it will allow complex surgical manipulation in the anterior chamber, improving visibility while protecting the corneal endothelium and surrounding tissues from the trauma of surgical instrumentation. It may also be used to aid atraumatically the cleavage of iris synechiae or other adherent tissues. Thus Healonid has a place in the field of trauma'8 (synechiolysis, extraction ofcorneal splinters penetrating the anterior chamber, anterior segment reconstruction), in keratoplasty459 (both for donor and recipient eye to protect endothelium), in filtration surgery' (to prevent flat anterior chamber and hypotonia), in extracapsular cataract extraction'6 (during capsulectomy and to protect endothelium from a hard lens nucleus),