Digital Image Analyses of Preoperative Simulation and Postoperative Outcome following Blepharoptosis Surgery

BACKGROUND: Before blepharoptosis surgery, simulation of eyelid features, including lid height and crease position, is often performed. However, discrepancies of the simulation and outcome can occur. The purpose of this study was to analyze the pre- and postoperative images and to evaluate factors contributing to the discrepancies. METHODS: Forty-one involutional blepharoptosis patients (68.2 ± 7.1 years) underwent levator aponeurosis advancement. A semicircular bent wire was used to push the preoperative ptotic eyelid up to simulate the postoperative appearance of the eyelid. Digital images of the simulation were compared with the appearance at 3 months after the surgery. The ImageJ software was used to analyze the pre- and postoperative margin reflex distance-1 (MRD-1), pretarsal show (PTS), fissure height (FH), and ocular surface area (OSA). Factors with a potential of affecting the predictability of simulation were determined. RESULTS: During simulation, the MRD-1 was 3.6 ± 0.4 mm, the PTS was 3.48 ± 1.2 mm, the FH was 8.5 ± 0.9 mm, and the OSA was 120.7 ± 22.3 mm(2). After the surgery, the corresponding values were 3.3 ± 1.2 mm, 3.3 ± 1.5 mm, 8.6 ± 1.4 mm, and 119.1 ± 25.1 mm(2), respectively. The postoperative MRD-1 was significantly smaller than that of the simulation (P = 0.005, paired t test). The MRD-1 simulation error was positively correlated with the length and width of the skin resection (all P < 0.05), and the PTS error was positively correlated with the length of the skin resection (r = 0.332, P = 0.031) and negatively correlated with the preoperative OSA (r = −0.588, P = 0.007). CONCLUSIONS: The postoperative appearance of the eyelid can be simulated fairly accurately by pushing up the upper eyelid with a curved wire. However, the MRD-1 tended to be overestimated, especially for cases requiring a large skin resection.