In vivo architectural analysis of 3.2 mm clear corneal incisions for phacoemulsification using optical coherence tomography

Purpose: To analyze in vivo the architecture of clear corneal incisions (CCIs) for phacoemulsification using optical coherence tomography (OCT). Setting: Anterior Segment Department, Asociacion Para Evitar la Ceguera en Mexico, Hospital Dr Luis Sanchez Bulnes, Mexico. Methods: A prospective masked study analyzed 20 unsutured CCIs placed superiorly and created in a uniplanar fashion with a 3.2 mm slit-angled metal keratome. All wounds were evaluated with a retinal OCT model 1, 3, and 30 days postoperatively. Intraocular pressure (IOP) and incision leakage were checked. The architecture was described according to the angle of incidence, apposition of the epithelial and endothelial margins, and wound sealing. Results: No leakage was detected. The angle varied from 33 to 85 degrees; angles greater than 75 degrees were done by a surgeon in training. Wound apposition at the epithelial margin was achieved in all cases. In contrast, imperfect apposition of the endothelial margin was seen in 45% of incisions on day 1 and in 15% on day 30. Incomplete sealing of the wound was seen by OCT in 25% of cases at 24 hours and persisted in 10% of all cases at 1 month. This gaping occurred on the endothelial side and never translated to the epithelial margin. No statistical correlation was found between gaping and the angle of the incision, IOP variations, or surgeon experience. Conclusions: Although in vivo CCIs caused minor anatomic imperfections, they were clinically stable independent of incision angle, IOP variation, and surgeon experience. Incision stability may be related to careful wound construction, epithelial viability, stromal edema, and efficient endothelial pumping.