• Cornea/External Disease

    Researchers compared the visual outcomes and complications relating to 2 techniques: nanothin Descemet stripping automated endothelial keratoplasty (NT-DSAEK) and Descemet membrane endothelial keratoplasty (DMEK).

    Study design

    This prospective, comparative study included eyes diagnosed with Fuchs dystrophy that were pseudophakic or were scheduled to undergo cataract surgery with or without endothelial keratoplasty. Both the NT-DSAEK and DMEK cohorts comprised 28 eyes each. Cases of NT-DSAEK were defined by a graft thickness of 50 µm or less. Preoperative characteristics were well-matched between the groups. Outcomes were analyzed at postoperative months 1, 3, 6 and 12.

    Outcomes

    At postoperative month 1, BSCVA was significantly better in DMEK eyes than in NT-DSAEK eyes (0.18 log MAR vs. 0.28 logMAR; P=0.049). However, by 3 months, this statistical significance was lost and by 1 year, BSCVA was approximately 0.07 logMAR in both groups. More than 90% of eyes in both groups showed improved visual acuity; none of the eyes experienced worsening visual acuity after surgery.

    There were no intraoperative complications, primary graft failures or rejections. One eye in the NT-DSAEK group developed complete detachment at 1 week but recovered after successful rebubble.

    Limitations

    Although preoperative characteristics were well-matched, this study was not randomized. The visual acuity assessor was not masked and therefore may have biased the visual acuity outcomes.

    Clinical significance

    A recent randomized, controlled trial published in the January 2019 issue of Ophthalmology, showed DMEK results in superior visual outcomes compared with ultrathin DSAEK (60–90 µm) for up to 12 months postop. This study suggests thinner DSAEK grafts—in this case, less than 50 µm—can offer visual outcomes that are comparable to DMEK. The adoption of DMEK is difficult for many surgeons because the techniques requires graft manipulations that substantially differ from those required for DSAEK. If thinner grafts can offer equivalent visual results to DMEK, NT-DSAEK might offer an attractive alternative for surgeons who have not made the jump to DSAEK. A well-designed randomized, controlled trial would be necessary to fully answer this question.