Characteristics and Factors of Incision-Related Descemet Membrane Detachment During Cataract Surgery: A Prospective Study

Incision-related Descemet membrane detachment (DMD) can arise at different stages of cataract surgery, but its real-time intraoperative characteristics and associated factors remain incompletely understood. This study aimed to characterize incision-related DMD in 2.65 mm clear corneal incisions and to identify factors associated with its occurrence using intraoperative optical coherence tomography (iOCT). A total of 179 patients (179 eyes) with cataracts underwent coaxial 2.65 mm clear corneal incision phacoemulsification with intraocular lens implantation. iOCT was used for real-time scanning of the corneal main incision, recording DMD occurrence and extent at each procedural step. The full cohort was used for descriptive analyses and to evaluate associations between baseline factors and DMD detected at any intraoperative stage. Irrigation/aspiration (I/A)-related exposures were evaluated in the primary I/A analysis cohort, comprising the 145 eyes that remained DMD-free at I/A initiation. The primary outcome was newly detected DMD, defined as the first detection of DMD during I/A or at any subsequent intraoperative stage. A new parameter, I/A incision-deformation time, was defined as the cumulative duration of instrument–incision engagement accompanied by visible incision deformation during the I/A stage. Intraoperative DMD was detected in 109 of 179 eyes (60.9%) and was first observed most frequently during I/A (43.1%). In the primary I/A analysis cohort (n = 145), longer I/A incision-deformation time (adjusted odds ratio [aOR] = 1.23; 95% CI, 1.12–1.36; P < 0.001) and greater nuclear hardness (aOR = 4.20; 95% CI, 2.08–8.50; P < 0.001) were independently associated with the occurrence of DMD. I/A incision-deformation time and nuclear hardness showed similar discrimination (area under the curve [AUC], 0.728 and 0.726, respectively), while their exploratory combination yielded an optimism-corrected AUC of 0.800. Longer I/A incision-deformation time and greater nuclear hardness were independently associated with DMD occurrence. I/A incision-deformation time may offer a reproducible quantitative measure of instrument–incision interactions during cataract surgery. Trial registration: ChiCTR2100042379. The Descemet membrane is a thin layer at the back of the cornea that can separate near the surgical incision during cataract surgery. Larger or persistent detachments may cause corneal swelling and delay visual recovery. Using real-time imaging built into the surgical microscope, we evaluated 179 patients undergoing routine cataract surgery. Incision-related Descemet membrane detachment was detected in 109 eyes (60.9%) and was most often first seen during irrigation and aspiration, when fluid irrigation and suction are used to remove the remaining lens material. To ensure that the surgical measurement preceded the detachment, we separately analyzed 145 eyes with no detachment when this stage began. In these eyes, detachment was more likely to occur with greater nuclear hardness and with longer periods in which the surgical instrument visibly deformed the corneal incision. The cumulative duration of this visible incision deformation provides a measurable way to describe the interaction between the surgical instrument and the incision.