VOL. 95, NO. 4
LETTERS TO THE JOURNAL
559
Figure (Coleman and Orcutt). Illumination from the walls of the light pipe used for intraocular surgery can provide light for assistants without distracting the surgeon.
ties of a flashlight. Increasing the length of the light pipe causes some reduction of light at the illumninating intraocular tip, so the length of tubing may need to be reduced depending on the surgical var iables.
"DOUGHNUT" BIMANUAL BIPOLAR DIATHERMY ELECTRODES BROOKS W. M C C U E N II, M.D., AND DYSON HICKINGBOTHAM Box 3802, Duke University Eye Center, Durham, JVC 27710 (Dr. McCuen)
Bimanual bipolar diathermy is one of several methods available for the preven tion and control of bleeding during vitre ous surgery.1 Alligator clips as well as specially designed insulated microclips have been used to convert the metallic intraocular portion of vitrectomy instru mentation into the two poles of a bipolar cautery. We have designed a new elec trode by modifying a rubber 0 ring so that it serves to attach a diathermy lead to the instrument shaft* (Figure, top). The "doughnut" design of the elec*Available from Optical Micro Systems, Inc., Danvers, Massachusetts.
Figure (McCuen and Hickingbotham). Top, "Doughnut" diathermy electrode. Bottom, "Dough nut" diathermy electrodes on vitreous cutter and fiberoptics for use in vitreous surgery.
trode minimizes its size, eliminates the possibility of the electrode slipping off the instrument, and prevents rotation of the lead on the instrument shaft from interfering with the surgeon's view of the operation (Figure, bottom). This elec trode is designed to be placed on the instrument at the beginning of surgery and to remain in place throughout the operation. "Doughnuts" of various sizes permit electrodes to be placed on vitre ous cutters, fiberoptics, microscissors, and other instruments so that endodiathermy is rapidly available if needed. REFERENCE 1. Charles, S., White, J., Dennison, C , and Eichenbaum, D.: Bimanual bipolar intraocular dia thermy. Am. J. Ophthalmol. 81:101, 1976.