High-speed cutters examined for improved outcomes

Surgeons question whether new retinal tools prevent surgical complications.

Issue: August 15, 2000

With the advent of high-speed vitreous cutters and disposable equipment, surgeons have begun to question whether these developments improve surgical outcomes, according to Jeffrey S. Heier, MD, of Ophthalmic Consultants of Boston.

“We have high-speed cutters. We have wide-angle viewing systems. Can these actually make a difference in the rate of proliferative vitreoretinopathy [PVR]?” Dr. Heier asked. “If we’re doing vitrectomies on the primary repair, does a more complete vitrectomy decrease the recurrence rate? Or does vitrectomy lead to a greater re-detachment rate regardless of the completeness of vitrectomy?”

Also, shaving the vitreous base risks damaging peripheral retina and causing iatrogenic breaks. He is planning a five-surgeon prospective study to answer those questions.

Dual-linear mode

This year, Dr. Heier began to incorporate the dual-linear mode of a high-speed cutter in cases of diabetic retinopathy and PVR. Although formal study results are not available, Dr. Heier said that he is incorporating use of the high-speed cutter and a dual-linear control feature into more of his surgical regimens.

The dual-linear mode allows Dr. Heier to control aspiration and cut rates without requiring the changing of settings on a vitrector. He also can shave vitreous and cut some membranes without switching to intraocular scissors.

“Since you have control of the aspiration, you can use no aspiration and just use the cutter to cut membranes without a risk of incarcerating retina into the cut port,” he said.

Dual linear mode also is useful for clearing dropped lenses or other more fibrotic material, he said.

“When I need high aspiration to pull the lens off of the retina, I can aspirate higher and vary the power based on what part of the lens I’m fragging,” Dr. Heier said. “Again that saves me time. In the past, we controlled the aspiration by our foot and constantly manipulated the power based on whether we were dealing with the nucleus or the cortex.”

Dr. Heier uses the Millennium system (Bausch & Lomb Surgical, Claremont, Calif.), which allows him to adjust the bottle height with a quick tap of the foot pedal. This allows Dr. Heier to adjust the bottle immediately if an intraocular hemorrhage occurs, instead of waiting for his staff to adjust the height. This is particularly important in submacular surgery.

“I can literally shut off the perfusion within a second or two,” he said. “There’s been several cases where I’ve found that to be very helpful.”

Wide-angle lenses also have changed the repair of complicated retinal detachments, he said. They allow surgeons to guide the high-speed cutters to maneuver out to the peripheral retina and to the ora in order to shave the vitreous base.

Now, Dr. Heier and colleagues want to know whether this advantage of being more aggressive with primary retinal detachments will decrease the rate of PVR or reoperations.

New equipment

Disposable vitreous cutters offer more precision intraoperatively, according to Etienne H. Bovey, MD, of Lausanne, Switzerland. He has used it for about 1 year, and said it is likely to reduce the incidence of retinal tears.

“Sometimes when you resterilize vitreous cutters, we can use a cutter that is not sharp and we may not notice it immediately,” he said. “So the risk of producing retinal tears during vitrectomy is increased. Therefore, a single-use cutter is certainly safer.”

Dr. Bovey uses a coaxial optic fiber that can be adapted on the vitreous cutter (Oertli Instrumente AG, Berneck, Switzerland). The diameter of the optic fiber is 1.6 mm. The fiber is resterilized with gas. This system of illumination of the fundus allows Dr. Bovey to perform a simple vitrectomy through two ports, one for the infusion and one for the vitreous cutter surrounded with the coaxial optic fiber. The conjunctiva is opened only over 90º. Furthermore, Dr. Bovey can indent the retina himself with the other hand, instead of relying on an assistant or resident.

For more complicated cases, a third sclerotomy is performed for the use of another instrument (forceps, scissors, etc.). The membranes that have been removed from the retina can be immediately aspirated in the eye with the vitreous cutter. This avoids the in-and-out movements of the forceps through the sclerotomy to remove these membranes, and it certainly contributes to reduce the risk of intraoperative peripheral retinal tears.

Surgery for proliferative diabetic retinopathy best illustrates the advantages of this coaxial optic fiber, Dr. Bovey said. The vascular fibrous tissue is aspirated with the vitreous cutter (one hand) and cut with the scissors (second hand). In this case, because the light probe is close to the retina, the intensity of the light source must be reduced. If bleeding occurs, the surgeon can aspirate the blood with the vitreous cutter and continue the dissection.

Also, if he wants to remove the vitreous on the periphery, it is easy for him to work with the vitreous cutter very close to the retina and indent the periphery with his other hand.

“If you ask a resident to indent, it is never in a good place,” Dr. Bovey said. “Sometimes the resident can indent too much and damage the retina. If I can work by myself, it is much better!”

For Your Information:

Jeffrey S. Heier, MD, can be reached at Ophthalmic Consultants of Boston, 50 Staniford St., Ste. 600, Boston, MA 02114; (617) 367-4800; fax: (617) 723-7028. Dr. Heier has no direct financial interest in any of the products mentioned in this article, nor is he a paid consultant for any companies mentioned.

Etienne H. Bovey, MD, can be reached at the Hopital Ophthalmique, Jules Gonin, Lausanne, Switzerland; (41) 21-626-8111; fax: (41) 21-626-8888. Dr. Bovey has no direct financial interest in any of the products mentioned in this article, nor is he a paid consultant for any companies mentioned.

Bausch & Lomb Surgical can be reached at 555 W. Arrow Highway, Claremont, CA 91711; (800) 423-1871; fax: (909) 399-1525.

Oertli Instrumente AG can be reached at CH-9442 Berneck, Switzerland; (41) 71-747-4200; fax: (41) 71-747-4290.