Comparison of outcomes of 25-gauge vs 27-gauge micro-incision vitrectomy surgery for visually significant macular membranes and full-thickness macular holes

Abstract

Purpose : Micro-Incision Vitrectomy Surgery (MIVS) offers an excellent safety profile for patients, while the newest 27-gauge (27G) systems have potential additional safety and outcome benefits when compared to earlier MIVS platforms.

This Institutional Review Board approved retrospective study reviews surgical outcomes following 25-gauge (25G) and 27G Pars Plana Vitrectomy (PPV) and Internal Limiting Membrane (ILM) peel surgeries for Epiretinal Membranes (ERM) and Full-Thickness Macular Holes (FTMH).

Methods : The Oregon Eye Consultants, LLC database was searched using diagnosis codes for ERM and FTMH, and procedure codes for PPV and ILM peel. Charts of 379 patients who underwent surgery from January 2017 through December 2018 were reviewed. 207 cases met inclusion eligibility criteria. The primary endpoint was Best-Corrected Distance Visual Acuity (BCVA) after 1 year. Secondary endpoints included intraocular pressure (IOP), post-operative complications, and OCT central foveal thickness (CFT) and macular volume (MV).

Results : The study included 207 eyes from 108 females and 97 males (mean age 72.4 ± 8.9; range 24 – 97 years). 88 eyes were phakic and 119 were pseudophakic pre-operatively. Of the 207 surgeries, 150 were for ERM and 57 for FTMH. For the ERM group, 102 surgeries were with 25G and 48 with 27G. For the FTMH group, 47 surgeries were with 25G and 10 with 27G.

For all patients combined, mean logMAR BCVA improved from 0.57 ± 0.40 to 0.37 ± 0.35 post-operatively (p<0.001). For 25G ERMs, logMAR BCVA improved from 0.51 ± 0.28 to 0.29 ± 0.21 post-operatively (p<0.001). For 27G ERMs, logMAR BCVA improved from 0.33 ± 0.29 to 0.28 ± 0.27 post-operatively (p=0.2). For 25G FTMHs, logMAR BCVA improved from 0.87 ± 0.48 to 0.52 ± 0.41 post-operatively (p<0.001). For 27G FTMHs, logMAR BCVA remained unchanged from 0.89 ± 0.47 to 0.89 ± 0.65.

For 25G ERMs, CFT reduced from 425.89 ± 89.06 μm to 360.1 ± 61.8 μm (p<0.001) and MV reduced from 9.99 ± 1.15 mm³ to 8.86 ± 0.76 mm³ (p<0.001). For 27G ERMs, CFT reduced from 464.15 ± 75.05 μm to 394.37 ± 42.76 μm (p<0.001) and MV reduced from 10.3 ± 1.32 mm³ to 9.09 ± 0.64 mm³ (p<0.001). Overall, there were no serious complications in any group (e.g. retinal detachment, endophthalmitis).

Conclusions : At 1-year follow up, both 25G and 27G were safe and well tolerated MIVS platforms for the treatment of ERMs and FTMHs.

This is a 2020 ARVO Annual Meeting abstract.