In complicated retinal detachment cases where the retina fails to reattach after completing the usual steps, retinectomy is a better technique than relaxing retinotomy–and the retinectomy is best done incrementally under air, said Steve Charles, MD.
Reviewed by Steve Charles, MD
In complicated retinal detachment cases where the retina fails to reattach after completing the usual steps, retinectomy is a better technique than relaxing retinotomy–and the retinectomy is best done incrementally under air.
“Retinectomy has advantages compared with relaxing retinotomy because retinectomy removes all the necrotic tissue anterior to the circumferential cut and reduces the risks of anterior segment neovascularization, chronic hypotony, and probably proliferative vitreoretinopathy (PVR) recurrence,” said Steve Charles, MD.
Dr. Charles is founder of the Charles Retina Institute and clinical professor of ophthalmology, University of Tennessee, Memphis. He also developed the retinectomy-under-air technique.
“An advantage of retinectomy-under-air rather than under-balanced, salt solution, or perfluoro-n-octane (PFO) is that the surgeon is better able to judge the right amount of tissue to remove,” Dr. Charles explained. “Retinectomy-under-air reduces the need for hemostasis, and by avoiding PFO, it saves money and eliminates subfoveal PFO.”
Figure 1. Courtesy of Steve Charles, MD
The need for performing retinectomy is established after completing the usual steps to identify and eliminate factors creating traction and preventing the retina from reattaching. The sequence begins with removal of frontal plane vitreous traction and anterior loop traction, followed by peeling of obvious epiretinal membranes, for which Dr. Charles advocates using internal limiting membrane (ILM) forceps. (See Figures 1-3.)
Figure 2. Courtesy of Steve Charles, MD
Figure 3. Courtesy of Steve Charles, MD
Next, any significant subretinal bands that are tenting up the retina are accessed by “punch-through retinotomy” performed using a closed forceps, said Dr. Charles, describing another technique he developed. (See Figures 4 and 5.)
Figure 4. Courtesy of Steve Charles, MD
Then, subretinal fluid is drained internally through the pre-existing retinal break, using a soft-tip cannula or vitreous cutter if there is potential for residual vitreous. When subretinal fluid stops decreasing during internal drainage, fluid-air exchange is started and continued simultaneously with internal drainage.
“Failure to reattach has nothing to do with poor technique, but occurs because of residual traction,” Dr. Charles added.
If the subretinal fluid stops decreasing before the retina is attached, surgeons should look for a contributing cause and can begin with a search for residual vitreous. If found, Dr. Charles recommended performing vitrectomy-under-air (“interface vitrectomy”).
Figure 5. Courtesy of Steve Charles, MD
“Don’t put in a perfluorocarbon liquid, triamcinolone, or infusion fluid,” Dr. Charles said. “Do vitrectomy-under-air, making sure the port is in the vitreous liquid component.”
He added that it can only be done using a peristaltic pump.
Drainage of subretinal fluid with fluid-air exchange might also reveal an overlooked epiretinal membrane, which should be peeled under air with an ILM forceps. If the retina still does not attach, surgeons should look again for a subretinal band and perform punch-through retinotomy with an end-grasping forceps as needed.
Retinectomy-under-air is performed only if the retina remains detached after all measures have been taken. It is done in an incremental fashion to remove only the amount of tissue that is necessary to reattach the retina. If, however, the retinectomy reaches 270°, it should be extended to 360° because the remaining quadrant will contract postoperatively, Dr. Charles said.
If bleeding occurs, surgeons should raise the pressure and apply confluent laser to severed large vessels. Confluent laser, not spots, is also applied to the retinectomy edge. Once hemostasis is achieved, the pressure can be lowered and air-silicone exchange can be done.
Steve Charles, MD
This article is based on a presentation given by Dr. Charles at the 2017 Retina World Congress. He had no relevant financial interests to disclose.