Ultrasonic fragmentation for vitrectomy and associated surgical procedures.

Ultrasonic fragmentation (USF) can be used to fragment various tissues such as the lens, the vitreous, the iris, and the ciliary body, so that they may be aspirated through a 23-gauge canula. Since the technique was first described in 1973, it has been used in 148 eyes in a variety of conditions with encouraging results. In aphakic bullous keratopathy, the corneas and vision improved in 78% of the cases. Pupillary block was relieved in 100% of cases. Cystoid macular edema improved in 63%. Vitreous opacification from other than hemorrhage cleared in all cases, and vision improved in 71%. Massive vitreous hemorrhage was cleared in 86%, and vision improved in 58%. In massive vitreous hemorrhage and retinal detachment, the vitreous was cleared and the retina reattached in 80% of cases. In massive vitreous contraction, the vitreous was removed in all cases and the retina reattached in all (100%) of cases. In massive vitreous membranes and retinal detachment, the membranes were successfully removed in 100% and the retina reattached in 82%. Lens remnants in the vitreous were removed in 100% of cases. Secondary membranes were removed successfully in 100% of cases. Vitreous presentation in the anterior chamber, caused by a ruptured posterior capsule during extracapsular extraction or actual vitreous loss during intracapsular extraction, was treated successfully in 100% of cases. One case of medullo-epithelioma of the ciliary body was removed but recurred twice after ultrasonic fragmentation. Complications occurred in seven of 148 cases (4.8%) and consisted of five cases of retinal detachment (probably because of lens material reaction) and two cases of epithelial downgrowth in cases where the wound was not closed with sutures. Ultrasonic fragmentation appears to be a fairly simple procedure, performed with a machine with no moving parts, through two 1-mm incisions and using two 0.6-mm cannulas, with a minimum of complications and encouraging results. It should be tried before more radical procedures are recommended. A good anatomic result was obtained in 129 of the 148 consecutive cases (88%). The technique is described and the results reported.