Phacoemulsification with trapezoid incision shape reduces incision-related DMD
Phacoemulsification with a trapezoid incision shape significantly reduced the incidence of incision-related Descemet membrane detachment (DMD) at postoperative day 1 compared with conventional 2.2-mm clear corneal incision, according to a study.
In this double-masked, parallel randomized clinical trial, 130 patients (130 eyes) between the ages of 65 to 90 years with age-related cataract, nuclear opalescence grade of ≥4.0, pupil size ≥6 mm after dilation, and corneal endothelial cell density >1500 cells/mm2, were randomized to undergo modified (enlarged internal width to 3.0 mm; n = 65) or conventional 2.2-mm incision (n = 65) phacoemulsification with intraocular lens implantation.
At postoperative day 1, the incidence of DMD in eyes in the modified group was significantly lower than eyes in the conventional group (difference, 26.15; 95% CI, 9.60-42.71; P = 0.003. At postoperative day 7, the difference was 16.92 (95% CI, 2.91-30.94; P = 0.02). In the modified group, length of DMD and maximal corneal thickness at the incision site were lower but the visual quality parameter modulation transfer function was higher.
Best-corrected visual acuity, central corneal endothelium loss, or surgically induced astigmatism was not different between the groups. No intraoperative complications were reported in either group.
The authors concluded that although modified 2.2-mm trapezoid incision phacoemulsification should be considered for patients at a high risk of incision-related DMD, clinical relevance was not determined with certainty from this trial.
Dai Y, Liu Z, Wang W, et al. Incidence of Incision-Related Descemet Membrane Detachment Using Phacoemulsification With Trapezoid vs Conventional 2.2-mm Clear Corneal Incision: A Randomized Clinical Trial. JAMA Ophthalmol. Published online October 14, 2021. doi:10.1001/jamaophthalmol.2021.4148