Surgery may help improve visual acuity when anti-VEGF drugs are not effective

June 15, 2008

Surgical therapy for age-related macular degeneration in the form of macular translocation, injection of tissue plasminogen activator, and gas tamponade provides some improvements in visual acuity for patients whose conditions do not respond to the anti-vascular endothelial growth factor drugs.

Frankfurt, Germany

-Surgical therapy for age-related macular degeneration (AMD) provides some improvements in visual acuity (VA) for patients whose conditions do not respond to anti-vascular endothelial growth factor (VEGF) drugs, according to Claus Eckardt, MD, professor of ophthalmology, Staedtische Kliniken Frankfurt am Main-Hoechst, Frankfurt, Germany.

"There is agreement today that, in the anti-VEGF drug era, macular surgery is indicated only in cases in which no improvement is expected with administration of ranibizumab [Lucentis, Genentech] or bevacizumab [Avastin, Genentech], such as in eyes with tears in the retinal pigment epithelium [RPE], large subretinal hemorrhages, or in eyes in which the VA has decreased despite the use of anti-VEGF therapy," he said.

Vitrectomy with removal of subretinal hemorrhage, macular translocation, injection of tissue plasminogen activator (tPA) and gas tamponade, and the still-experimental translocation of the choroid and RPE are the macular surgeries currently performed, Dr. Eckardt said.

Three approaches

He provided examples of the former three approaches. In the case of an eye in which a large tear in the RPE developed 15 days after the patient had received an injection of bevacizumab, Dr. Eckardt relayed, near vision was adversely affected, but distance vision remained intact. Two additional injections of the drug did not restore reading vision, so the patient underwent macular translocation surgery. Seven months postoperatively, VA improved to 0.5, and near vision returned. In another patient, VA was 0.2. After translocation surgery, VA increased to 0.8 and has remained stable for 4 years.

"I am not aware of another surgery other than translocation surgery that would be more successful to repair rips in the RPE," he said.

A report of eight cases published by Yusuke Oshima, MD, PhD, and colleagues from the Osaka University Graduate School of Medicine and Faculty of Medicine in Japan described how the authors drained the liquid blood from eyes 24 hours after the injection of tPA. They drained the blood through two small peripheral retinotomies by injecting perfluorocarbon liquid onto the retina. VA had improved significantly in all eyes except one by 2 years after the procedure, Dr. Eckardt said. He recounted that his group performs a large peripheral retinotomy (~250º). They then reflect the retina to remove the blood and fibrovascular proliferation. In the presence of a small RPE defect, the retinotomy is enlarged to 360º, and macular rotation is performed.

The procedure is easy to perform if the hemorrhage is not fluid, Dr. Eckardt said; if the hemorrhage is fluid, then performing the retinotomy can be difficult because the blood can obscure visualization.

In a patient who presented to him 8 months after reading vision was lost because of submacular choroidal neovascularization, 2 months after a hemorrhage that further decreased vision, and after six intravitreal bevacizumab injections, the subretinal blood was removed via a 250° peripheral retinotomy. About 18 months after the procedure, the vision is 0.2, and the foveal fixation has been regained. In addition, the patient was able to return to work 1 week after the procedure, Dr. Eckardt recounted.

“Our results with intravitreal tPA and gas injection have not been good, but still we attempt the procedure,” he said.In another case, a 78-year-old patient presented with a hemorrhage that had occurred only 1 hour previously. Dr. Eckardt and colleagues performed macular translocation surgery 1 day later. Sixteen months later, VA has improved from 0.1 to 0.8 in the better eye. The patient was able to return to medical practice 6 weeks after the silicone oil was removed.

Between 2003 and 2006, Dr. Eckardt and associates performed macular rotation surgery in 38 eyes with massive submacular hemorrhages. The cases had a mean follow-up of 22 months. Distance VA was better than 20/60 in 16 eyes and better than 20/30 in six eyes, and reading VA was better than 20/50 in 23 eyes, he said. Despite the good results, Dr. Eckardt said that such a retrospective study does not prove the effectiveness of this procedure.

“I do not advocate the use of translocation in all cases of massive hemorrhages,” he said. “We have learned that about 1 to 3 years postoperatively, almost all eyes developed changes in the subfoveal RPE that may be seen only on angiography. Usually, the vision remains good with foveal fixation.

“Translocation is a risky procedure because there is a high risk of complication,” he added. “The procedure is complex, and the learning curve is steep. There is little opportunity to learn the procedure, because it is rarely performed.”

Dr. Eckardt and his colleagues performed translocation surgery on 30 to 50 cases annually until the introduction of bevacizumab in 2007; the number dropped to nine surgeries in 2007.

Another option

Another surgical option for surgeons who have no experience with translocation surgery is pneumatic displacement of hemorrhages with tPA, which was shown to improve VA in 60% and 64% of cases in two studies, Dr. Eckardt said. Without the use of tPA, 100% of eyes had a visual improvement.

Because these studies were done before the availability of anti-VEGF therapy, it is possible that the VA results after pneumatic displacement can improve with intravitreal injections of these agents postoperatively, he said.

“Massive submacular hemorrhages and RPE tears will continue to be encountered despite all the recent benefits of therapy for AMD,” Dr. Eckardt said. “It is difficult to imagine that these complications can be treated without surgery. I wish that each country had at least a few centers with the expertise to perform the entire spectrum of submacular surgery.”OT