Smaller corneal incision linked to greater incisional thickening in cataract surgery for hard nuclei

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Frontiers in Medicine Published April 12, 2026 Medically reviewed April 25, 2026 DOI ↗ By Dr. Lars van Dijk, PhD · Surgical, Procedural & Diagnostic

Key Takeaway

Note greater incisional thickening with 2.2 mm vs. 2.6 mm incision in hard cataracts, per small retrospective data.

This retrospective cohort study analyzed 100 eyes (50 per group) with nuclear hardness grades III to V undergoing phacoemulsification. Patients received either a 2.2 mm or a 2.6 mm corneal incision, with outcomes assessed at 1 day, 1 week, 1 month, and 3 months postoperatively. The primary outcome was not explicitly stated, but multiple secondary surgical and anatomical parameters were evaluated.

Key results showed no statistically significant differences between groups for cumulative dissipated energy (CDE), ultrasound time (UST), endothelial cell density (ECD) reduction, best-corrected visual acuity (BCVA) improvement, or central corneal edema (all P > 0.05 for intergroup comparisons). Both groups experienced a significant postoperative decline in ECD and a transient increase in central corneal thickness (CCT) at 1 day and 1 week. However, incisional corneal thickness (ICT) increased significantly more in the 2.2 mm incision group compared to the 2.6 mm group at the 1-day and 1-week time points (P < 0.05).

Safety and adverse events were not reported. Key limitations include the retrospective design, small sample size, lack of a clearly defined primary outcome, and absence of reported absolute numerical data or effect sizes, which limits the precision of the findings.

For practice, this study suggests that in eyes with hard nuclei, a smaller 2.2 mm corneal incision may be associated with greater localized incisional thickening in the immediate postoperative period compared to a 2.6 mm incision, without differences in energy use or final visual acuity. Surgeons should interpret this single, small retrospective finding cautiously, as its clinical significance for wound healing or long-term stability is unclear.

Study Details

Study typeCohort

EvidenceLevel 3

PublishedApr 2026

View Original Abstract ↓

PurposeThis study sought to evaluate the differential impacts of two corneal incision sizes, 2.2 mm and 2.6 mm, on the utilization of intraoperative ultrasound energy and the subsequent postoperative corneal recovery in patients presenting with hard nuclear cataracts.MethodsA retrospective cohort study was undertaken, encompassing cataract patients classified with nuclear hardness grades III to V according to the Emery-Little classification. Participants were allocated into two groups based on the incision size: 2.2 mm and 2.6 mm. Key metrics, including endothelial cell density (ECD), central corneal thickness (CCT), incisional corneal thickness (ICT), and best-corrected visual acuity (BCVA), were assessed preoperatively and at intervals of 1 day, 1 week, 1 month, and 3 months postoperatively. Additionally, intraoperative phacoemulsification parameters and any complications were documented.ResultsThe study encompassed a total of 100 eyes, with 50 eyes in each group. No statistically significant differences were detected in cumulative dissipated energy (CDE) or ultrasound time (UST) between the two groups (P > 0.05). Both groups exhibited a significant postoperative decline in ECD (P < 0.05), yet no significant intergroup difference was observed in the magnitude of this reduction (P > 0.05). Central corneal thickness (CCT) and intraocular pressure (ICT) exhibited a statistically significant increase at both 1 day and 1 week postoperatively when compared to baseline measurements (P < 0.05). Notably, the increase in ICT was significantly more pronounced in the 2.2 mm incision group at both time points (P < 0.05). Best-corrected visual acuity (BCVA) showed significant improvement in both groups following surgery (P < 0.05), with no significant intergroup differences observed at any follow-up interval (P > 0.05). Additionally, no significant difference in central corneal edema was detected between the two groups (P > 0.05).ConclusionThe corneal incision size (2.2 mm versus 2.6 mm) did not influence the use of intraoperative ultrasound energy or result in differential corneal endothelial cell loss. However, smaller incisions (2.2 mm) were associated with increased short-term edema at the incision site, potentially impacting early wound healing.