PurposeTo compare the results in terms of visual acuity and complication rates between eyes undergoing Descemet's membrane endothelial keratoplasty (DMEK) with the help or not of intraoperative optical coherence tomography (iOCT).MethodsNon-randomized retrospective comparative study including 288 eyes of 227 patients (age, 30 to 90 years) undergoing DMEK surgery with the use of iOCT (OPMI Lumera 700 surgical microscope, Carl Zeiss Meditec, Jena, Germany) (135 eyes, iOCT group) and without it (153 eyes, non-iOCT group. Corrected distance visual acuity (CDVA) and complication rates were evaluated during a 24-month follow-up.ResultsSignificantly worse CDVA (p=0.010) and more equally distributed the Fuchs endothelial corneal dystrophy/bullous keratopathy (p=0.001) were found in iOCT group preoperatively. A difference close to the statistical significance was found in CDVA at 1 month after surgery, with a trend to a better visual outcome in the iOCT group (p=0.066). Likewise, a significantly larger CDVA improvement was found in iOCT groups at 1 (p=0.002), 3 (p=0.012) and 6 months after surgery (p=0.032), with no difference between groups afterwards. No significant differences between groups were found in the re-bubbling rate (p=0.597): iOCT 17/135 (12.6%) vs. non-iOCT 15/153 (9.8%). A trend to a lower rate of primary failure of the transplant in the iOCT group was found, but it did not reach statistical significance (5/135, 3.7% vs. 13/153, 8.5%, p=0.097).ConclusionsiOCT-assisted DMEK allows a faster visual recovery during the initial 6 months after surgery than DMEK procedures performed without the use of such technology.