Vitrectomy possible treatment for diabetic macular edema

Chicago-Vitrectomy should be considered for some eyes with diabetic macular edema (DME), according to Tarek Hassan, MD, who spoke during the retina subspecialty day at the American Academy of Ophthalmology annual meeting.

Dr. Hassan, who is assistant professor of Biomedical Sciences, Oakland University, Royal Oak, MI, explained that eyes with diffuse clinically significant DME-which do not respond as well to laser treatment as focal clinically significant DME-may benefit from vitrectomy because of studies over more than a decade that have indicated that vitrectomy membrane peeling with or without internal limiting membrane peeling relieves posterior hyaloid traction and can result in visual improvement in these eyes thought to be refractory to treatment.

Numerous studies have shown visual improvement in eyes with a visibly taut, opacified posterior hyaloid membrane; with an attached but not clinically visible taut posterior hyaloid membrane; with a preoperative detached posterior hyaloid; and with massive subfoveal hard exudates.

There are questions about how vitrectomy works in these eyes, but evidence seems to indicate that vitrectomy relieves the anteroposterior vitreomacular traction and the tangential traction. The role of the internal limiting membrane seems important and its removal ensures the elimination of all posterior hyaloidal traction and decreases the recurrence of clinical significant DME after vitrectomy. Better visual prognosis may be expected in eyes with a short duration of clinically significant DME, little or no macular ischemia, mild preoperative laser treatment, an obvious taut posterior hyaloid, good preoperative visual acuity, and no preoperative foveal hard exudates, he explained.

“Vitrectomy should be thought of as a long-term efficacious treatment for some eyes with refractory macular edema. The role of vitrectomy must be defined and compared with intravitreal triamcinolone and laser treatment, but vitrectomy may provide a more permanent solution for some eyes,” Dr. Hassan said. “The vitreomacular interface is the key and optical coherence tomography must help demonstrate posterior hyaloid traction whether it is anteroposterior or tangential in its dimension.

“Ultimately, vitrectomy should be in all surgeons’ armamentarium for this disease because it does stabilize or improve vision in eyes that would otherwise worsen,” Dr. Hassan said. He looked to the future for possible combination therapies with vasopermeability inhibitors.