Research offers insights to success in macular hole surgery

Reviewed by John T. Thompson, MD

Dr. ThompsonMacular hole surgery can be performed using various techniques and technologies. According to John T. Thompson, MD, the available evidence supports always incorporating internal limiting membrane (ILM) peeling, staining of the ILM, and having a large gas bubble in the eye on the first postoperative day.

Achieving the latter also may allow for a shorter duration of prone positioning, said Dr. Thompson, assistant professor, Wilmer Eye Institute, Johns Hopkins University, and partner, Retina Specialists, Baltimore, MD.

ILM issues

Citing a Cochrane meta-analysis that included four randomized trials [Cornish, et al. Ophthalmology. 2014;121(3):649-655], Dr. Thompson said there is strong evidence that peeling the ILM improves the rate of macular hole closure.

“In that review, ILM peeling was associated with a significantly higher rate of both primary and final macular hole closure, with odds ratios of 9.27 and 3.99, respectively,” he reported.

Dr. Thompson observed that a stain should be used to assure complete ILM removal. Options include trypan blue 0.15% (MembraneBlue, DORC), Brilliant Blue G 0.025% (DORC), and indocyanine green (ICG, usually 0.1%). The approval status and commercial availability of these products varies in different countries. In the United States, Brilliant Blue G is available only from compounding pharmacies and ICG does not have an FDA-approved indication for ILM staining.

The three staining options also vary in their efficacy and safety, Dr. Thompson said.

“Trypan blue does not stain the ILM very well,” Dr. Thompson explained. “Brilliant Blue G stains the ILM better and has an excellent safety profile. ICG gives the best staining, but can cause retinal pigment epithelium toxicity and so needs to be used with some cautions.”

Triamcinolone also can be used as an aid for ILM peeling. It does not stain the ILM per se, but when dusted on the macula, it allows the surgeon to see where the ILM has been removed.

Tamponade techniques, prone positioning

Tamponade techniques, prone positioning

Dr. Thompson said visual results from several studies support the use of gas rather than silicone oil for tamponade. However, silicone oil is used for difficult macular holes.

For prone positioning, there has been a trend toward a shorter duration. Data from the 2015 Preferences and Trends Survey of the American Society of Retina Specialists showed that the majority of American respondents were recommending ≤7 days, with the largest group (47.6%) recommending 5 to 7 days.

OCT image of a stage 2 macular hole of recent onset. Courtesy of John T. Thompson, MD

Dr. Thompson said the short-duration, prone positioning for a several days can be used with a shorter-acting gas bubble, either air or sulfurhexafluoride (SF6), but the longer-acting gas, perfluoropropane (C3F8), is needed if prone positioning is not done.

“An analysis of 2,456 eyes in a New Zealand registry found SF6 was non-inferior to C3F8 for holes ≤400 µm, but the researchers could not conclude that SF6 was not non-inferior to C3F8 for larger holes,” Dr. Thompson said, adding that C3F8 is best used in pseudophakic eyes because of its associated risk for causing a gas-induced cataract with short-duration prone positioning.

Whether using SF6 or C3F8, a large fill (>80%) is necessary in the first postoperative day to maintain coverage over the macular hole, regardless of gaze and body position.

Japanese report

Japanese report

As reported by Japanese surgeons [Yamashita, et al. Retina. 2014;34(7):1367-1375], Optical coherence tomography can monitor the status of the macular hole and determine the need to continue prone positioning, but their use of this approach involved daily follow-up.

“Most macular holes close in 24 to 48 hours, and in this study, a closure rate of 96.2% was achieved with a mean prone positioning duration of 42 hours,” Dr. Thompson said. “However, there are some macular holes that can take seven days to close.”

Results of a Cochrane review of three randomized, controlled trials evaluating prone positioning support its consideration in eyes with large macular holes [Cochrane Database of Systematic Reviews 2001, Issue 12. Art no.: CD008228]. The analyses showed prone positioning had no significant benefit overall, but it was associated with a higher closure rate for holes >400 µm.

Dr. Thompson also noted that vitrectomy is more cost-effective than ocriplasmin (Jetrea, ThromboGenics) for treating macular holes, and the reason relates to the high cost of the pharmacologic agent. A cost benefit analysis comparing the two techniques calculated that the cost per quality-adjusted life year ranged from $5,444 to $7,442 for vitrectomy and from $8,159 to $10,244 for ocriplasmin [Chang JS, Smiddy WE. Ophthalmology. 2014;121(9):1720-1726].

John T. Thompson, MD

E: jthompson@retinaspec.com

This article is based on a presentation given by Dr. Thompson at the Retina Subspecialty Day, held prior to 2016 American Academy of Ophthalmology meeting. Dr. Thompson has no financial interests relevant to the material discussed.