Face-down Position After Macular Hole Surgery Is Not Necessary
The rationale behind no–face-down posturing for macular hole repair.
PAUL E. TORNAMBE, MD
In 1990, the retina landscape changed following a presentation at the AAO by Neil Kelly, MD, who reported that he and Robert Wendel, MD, were able to repair some macular holes. The presentation was met with disbelief; the paper’s discussant stated that Dr. Kelly must be operating on pseudoholes. The manuscript was initially rejected by Ophthalmology.
Dr. Kelly and I had worked together earlier on papers about pneumatic retinopexy (PR). I knew he was a smart, honest surgeon, so I flew to Sacramento to see what he was doing. I learned how to remove the posterior hyaloid using the “fish strike” sign (a bend in a soft-tip cannula when the posterior hyaloid is engaged), and soon thereafter, I was also able to close many macular holes.
I do not recall any mention of specifically removing the internal limiting membrane, although Dr. Kelly did remove some “tissue” at the border of the hole. To the best of my recollection, he advised not operating on holes in eyes with better than 20/100 or so vision because, he said, the surgeon could make them worse if the operation failed. He also advised face-down positioning, as I recall, to keep the gas bubble away from the lens to avoid cataract formation.
The rest, as the saying goes, is history. Over a period of a few years, we went from a retinal problem that had no cure to an operation that would improve vision in most cases.
Paul. E. Tornambe, MD, is a private practice retina specialist and serves on the voluntary clinical faculty at the University of California at San Diego Department of Family Practice and Preventive Medicine. He reports no financial interest in any products mentioned here. He can be contacted at firstname.lastname@example.org.
WHEN A HOLE ISN’T REALLY A HOLE
At that time, I was interested in PR and believed that the purpose of the bubble was not to push the retina back into position (ie, bubble buoyancy) but was merely to “plug the hole” so liquid vitreous could not travel from the vitreous cavity to the subretinal space.
I was amazed by how quickly the retinal pigment epithelium pump removed subretinal fluid once the hole was “patched” by the gas bubble. In many patients, a total retinal detachment was completely attached by the next morning. The only logical reason for a surgeon to advocate face-down posturing for macular holes would be the belief that the buoyancy of the bubble plays an important role in hole closure, and I do not believe this theory is true.
I reviewed the research of Richard Green, MD, into the histopathology of macular holes (optical coherence tomography was not available at that time), and I came to the conclusion that a macular hole was not a “hole or defect with absence of retinal tissue” but more like a swollen cellulose sponge drawbridge, with fluid in the inner nuclear and outer plexiform layers of the retina.
This drawbridge, when no longer swollen, made the hole/defect “disappear” (by lowering). If the posterior hyaloid traction were released, and the defect could be isolated from the vitreous with a gas bubble, as we did with retinal detachments using PR, then surely the RPE could remove the small amount of intraretinal and subretinal fluid from the macula.
Once I learned from Dr. Kelly how to safely and consistently remove the posterior hyaloid from the macular surface, releasing posterior hyaloid traction, I believed that the RPE would suck the retina back into place and keep it there, as it does in the periphery with round nontractional retinal holes. I even tried PR on several macular holes, and in a few cases, it worked, probably because the gas bubble lysed the vitreous strands from around the hole (again, this was before OCT, so we could not see what was really happening), but PR failed to work in most macular hole cases.
My first attempt at macular hole repair without face-down positioning was in a frail elderly pseudophakic woman who, due to kyphosis, could not lie face down. The hole was not large, so I peeled the posterior hyaloid and filled the eye with long-acting C3F8 gas. The procedure worked. I operated on several more pseudophakic eyes and succeeded in approximately 66%. Many failures were stage III and IV holes (larger holes without posterior hyaloid traction).
Today, I realize that these procedures failed because the ILM was not peeled. In the mid-1990s, we were not factoring in the ILM and were not using indocyanine green. We did sometimes “scratch” the inner retina around larger holes trying to draw the edges of the hole together, but no one actually intentionally tried to peel the ILM.
I tried the no-face-down technique on several phakic eyes, and it worked, but they promptly developed cataracts, requiring subsequent surgery within a few weeks. Therefore, I subsequently advocated removing the cataract a week or two before or at the same time as macular hole repair (assuming we could coordinate the procedure with a cataract surgeon).
I observed that several patients who had the lens removed after macular hole repair developed cystoid macular edema, but CME almost never developed if the lens was removed prior to or concurrently with the macular hole operation. I do not know why, but sometimes, the observation precedes the explanation.
The only problem I encountered when performing lens replacement at the time of vitrectomy was displacement of the intraocular lens out of the bag by the gas bubble with pupil capture, so I used pilocarpine 1% at the end of the surgery and for approximately one week after the operation. The patients were advised to sleep with the operated eye up and to avoid face-up positioning.
We presented the data at AAO and were severely criticized for removing insignificant cataractous lenses and for the low success rate, which was approximately 70%. Many of our cases were large stage III or IV holes, and we did not peel the ILM. I now realize that the 70% success rate had nothing to do with positioning but was due to the size of the hole and the impact of not removing the ILM.
THE LEARNING CURVE
There was understandable skepticism from the retinal community. Surgeons were obtaining 80% success rates or better with face-down positioning and then better than 95% with ILM peeling and face-down positioning. Everyone was reporting high success rates, so why change? This argument was similar to the argument we used in advocating for antibiotics before and after intravitreal anti-VEGF injections: The infection rate was very low using antibiotics, so why change? The answer is that it really did not make a difference.
The reason surgeons should change their position on positioning is that some patients are denied macular hole surgery because they tell the doctor they physically cannot lie face down, and the doctor refuses to operate. Other patients, when told they must lie face-down for one to two weeks decline surgery because such restrictions are not compatible with their lifestyle.
Due to the miracle of the Internet, patients, after reading some of my publications, contact me for advice. Many Web sites advocate face-down posturing. For this reason, I refer patients to the Web site I created: macularholesurgeons.com. The site lists doctors from around the country and even from around the world who do not require face-down positioning. Many patients subsequently have had macular hole surgery performed by one of these doctors who practices in their area.
Although I have lectured extensively on this topic, and over the last decade, many peer-reviewed papers have confirmed that face-down positioning is not necessary, I would estimate that less than 10% of retinal surgeons routinely advise no positioning.
The clinical trials with ocriplasmin (Jetrea, ThromboGenics, Iselin, NJ) provided more evidence that face-down posturing is not necessary to close a macular hole. One might argue that many holes operated with vitrectomy alone may not even require a gas bubble, much less positioning!
I think most retina surgeons who advocate face-down posturing have never tried nonposturing. I continue to believe that, if the posterior hyaloid is removed, and the ILM is peeled in a broad 1-disc diameter margin about the hole, a 25% SF6 bubble works almost every time, even for reoperations. Almost every failed case I have reoperated on has failed because some or all of the ILM still surrounds the hole.
If the holes are large (600 to 750 µm), I use a 15% C3F8 bubble and still advocate no-face-down posturing. Habits are hard to break! RP