Despite comparable outcomes and operative times between preloaded, trifolded Descemet membrane endothelial keratoplasty (DMEK) grafts delivered via a DMEK cartridge system and other common surgical techniques, patients may experience potential complications unique to this method. This is according to research published in Cornea.
Researchers conducted a retrospective study to evaluate clinical outcomes and complications associated with trifolded (endothelium-in) DMEK procedures with donor tissues preloaded by the eye bank and delivered using the device. Adult patients with corneal endothelial dysfunction who received DEMK via the prescribed method, who had a minimum of 1-month follow-up, were included in the study.
The cohort included 35 eyes from 29 patients (mean age, 69.23±9.94 years; 57.1% men) who underwent DMEK. Within this group, 74.3% of eyes had Fuchs endothelial dystrophy, 17.1% of patients had pseudophakic bullous keratopathy, 5.7% had a previously failed Descemet-stripping endothelial keratoplasty, and 2.9% had herpes simplex virus endotheliitis.
Sixty percent of patients underwent triple-DEMK, while 31.4% underwent DMEK only; of the remaining patients, 2.9% received DMEK simultaneous with band keratopathy chelation and removal, and 5.7% underwent DMEK incorporated with AC intraocular lens removal.
Because the use of preloaded tissue may reduce preparation time in the operating room, investigators evaluated nursing records to assess mean time from time-out to closure, as well as changes over time due to learning curves. Mean operative time was 41.29±16.45 minutes for all cases; time was less in DMEK only (29.64±11.31 minutes) and longer in triple DMEK (42.64±11.26).
Investigators were able to retrospectively view video recordings from 68.6% of cases. Average tissue entry to air bubble placement time was 4.27±4.03 minutes), with an insignificant difference in time from tissue entry to air bubble injected between injected and pull through cases (median, 3.53 vs 3.27 minutes).
Average duration of follow-up was 6.40±3.02 months. Median preoperative best spectacle corrected visual acuity (BSCVA) was 0.398 logMAR (Snellen equivalent, approximately ~20/50 range). This measure significantly improved to 0.176 logMAR and 0.097 logMAR at 1 and 6 months, respectively (Snellen equivalent, approximately 20/30 and 20/25 range). A Snellen BSCVA of ≥20/25 was noted in 17.6% of eyes at 1 week, 34.3% of cases by 1 month, 46.7% of patients at 3 months, 53% of eyes by 6 months, and 55.5% of cases by 9 months follow-up.
In patients with DMEK only, median preoperative spherical equivalent of -0.56 diopters shifted to -0.013 diopters at 6 months postoperative.
Median baseline central corneal thickness increased from 619 µm to 650 µm at week 1, then improved to 554 µm at 1 month. Median postprocessing donor ECC of 2890.5 cells/mm2 reduced to 2057.5 cells/mm2 at 1-week follow-up. Across consecutive visits, no significant differences were noted at months 1, 3, and 6.
Postoperatively, 8.57% of cases had >30 mmHg intraocular pressure (IOP). Sixteen patients (45.71%) underwent rebubbling within 7.41(±4.65) days postoperatively, with no siginficant association noted between rebubbling and ECC at 1, 3, or 6 months.
One patient experienced new onset cystoid macular edema 40 days postoperatively. This improved with difluprednate 0.05% ophthalmic emulsion and ketorolac tromethamine 0.5% ophthalmic solution administered 4 times daily for 30 days. Another patient experienced posterior synechiae formation resulting in glare; this eye underwent posterior synechoilysis to separate the fibrinous adhesions. Primary graft failure occurred in 1 patient who underwent triple DMEK due to inverted graft markings by the eye bank.
Study limitations include the small sample size and retrospective nature and significant comorbidities in one subset of eyes which prevented accurate visual outcome comparisons.
The data in this series demonstrate that preloaded, trifolded DMEK grafts inserted into the eye results in outcomes and operative times comparable with common techniques but with potential complications unique to this method,” the research explains.
Disclosure: One study author declared affiliations with the biotech or pharmaceutical industries. Please see the original reference for a full list of authors’ disclosures.
Ighanzi M, Dzhaber D, Jain S, De Rojas JO, Eghrari AO. Techniques, outcomes, and complications of preloaded, trifolded Descemet membrane endothelial keratoplasty using the DMEK EndoGlide. Cornea. 2021;40(5):669-674. doi:10.1097/ICO.0000000000002648