Peeling off the layers of complex retinal detachments
By David RP Almeida, MD, MBA, PhD
Complex retinal detachments secondary to proliferative vitreoretinopathy, proliferative diabetic retinopathy, and uveitis represent challenging cases for the vitreoretinal surgeon. These complicated retinal detachments are analogous to onions with layers of pathology that need to be addressed. Successful outcomes in these cases require that, much as one would “peel” an onion, surgeons “peel” or remove each layer of pathology. Conceptually, there are three planes or layers — with respect to the neurosensory retina — to be addressed:
Above: preretinal adherent posterior hyaloid
In: proliferative membranes, epiretinal membranes and internal limiting membrane
Below: subretinal bands
ABOVE THE RETINA: Posterior hyaloid removal
Not uncommonly, a triamcinolone-stained residual layer of vitreous can be found over the posterior pole and peripheral retina in many eyes with complex retinal detachments; this include some eyes with a preexisting posterior vitreous detachment or Weiss ring.
Utilizing a Tano diamond-dusted membrane scraper (Figure 1A), forceps, or the vitreous cutter on aspiration (Figure 1B), the adherent posterior hyaloid needs to be removed.
The adherent posterior hyaloid is likely part of a spectrum of proliferative pathology related to incomplete posterior vitreous detachment, vitreoschisis, and immature membrane formation.
Figure 1A Figure 1B
IN THE RETINA: Epiretinal membranectomy and internal limiting membrane removal
Frank membrane formation, in the form of epiretinal membranes, leads to traction and foreshortening of the retina; consequently, these need to be removed as the presence of epiretinal membrane is 8.00 times (crude odds ratio, 95% CI: 1.43 - 44.92, p = 0.0182) more likely to have proliferative membrane formation.
Presence of cystoid macular edema in complex retinal detachment is 8.33 times (crude odds ratio, COR, 95% CI: 1.23 - 56.67, p = 0.0302) more likely to have subsequent membrane formation. Internal limiting membrane removal can minimize occurrence of cystoid macular edema.
Membranectomy can be efficiently achieved with forceps (Figure 2) or small-gauge vitrector handpiece on aspiration.
One of my favorite techniques is to use end-grasping (ILM-type) forceps and, in the closed position, abrade the retina to engage epiretinal membranes; then, membranes can be removed with tangential peeling in the usual manner (See related video below).
BELOW THE RETINA: Subretinal bands
Contrary to proliferative epiretinal membranes, not all subretinal bands need to be removed. Specifically, subretinal bands involving the macula or limiting your ability to re-attach the retina need to be removed. A small retinotomy with endothermy followed by forceps-assisted removal is a straightforward approach.
If a scleral buckle has not been placed previously, I recommend placing one in during complex retinal detachment cases. Even if only an encircling band (e.g., 41 band), this will provide support of the vitreous base and act as a barrier to anterior retinal contracture in cases where subsequent anterior membrane formation occurs.
Dr. Almeida repairs a complex retinal detachment.
1. Chin EK, Almeida DR, Folk JC. Posterior hyaloid removal. Ophthalmic Surg Lasers Imaging Retina. 2015;46(4):404.
2. Almeida DR, Chin EK, Roybal CN, Elshatory Y, Gehrs KM. Multiplane peripheral dissection with perfluoro-n-octane and triamcinolone acetonide. Retina. 2015;35(4):827-828.
3. Xu K, Chin EK, Mahajan VB, Almeida DR. Intravitreal foscarnet with concurrent silicone oil tamponade for rhegmatogenous retinal detachment secondary to viral retinitis. Retina. 2016;36(11):2236-2238.
4. Xu K, Chin EK, Almeida DR. Five-port combined limbal and pars plana vitrectomy for infectious endophthalmitis. Case Rep Ophthalmol. 2016;7(3):289-291.
5. Kuriakose RK, Xu K, Chin EK, Almeida DR. Proliferative Vitreoretinopathy (PVR) Update: current surgical techniques and emerging medical management. J VitreoRetin Dis. 2017;1(4):261-269.
6. Xu K, Chin EK, Bennett SR, et al. Predictive factors for proliferative vitreoretinopathy formation after uncomplicated primary retinal detachment repair. Retina. E-pub ahead of print: May 21, 2018.
7. Xu K, Chin EK, Parke DW, Almeida DR. Epiretinal membrane and cystoid macular edema as predictive factors of recurrent proliferative vitreoretinopathy. Clin Ophthalmol. 2017;11:1819-1824.
Dr. Almeida is a board-certified ophthalmologist and vitreoretinal surgeon with Erie Retinal Surgery in Erie, PA. He can be reached via firstname.lastname@example.org or Twitter (@davidalmeidaMD).