RESUMEN
PURPOSE: To investigate the relationship between postoperative scar height and surgical success of the bilamellar tarsal rotation (BLTR) procedure, commonly used to correct trichiasis secondary to trachoma. METHODS: Using data from the Partnership for the Rapid Elimination of Trachoma surgical trial, comparing the new trachomatous trichiasis (TT) clamp with standard BLTR instrumentation, 145 sequential participants (245 eyelids) at their 1-year postoperative visit were examined. We measured internal and external scar heights from the upper eyelid margin for nasal, central and temporal sections and compared these to recurrence location at 1 year. We calculated odds of location-specific postoperative trichiasis and examined possible risk factors associated with postoperative trichiasis. RESULTS: A total of 77 eyelids (31%) had postoperative trichiasis, which most commonly occurred centrally. Regardless of instrumentation used, the closer the internal scar was to the eyelid margin, the higher the proportion that had recurrence, until 4.5 mm, at which point, the proportion leveled off. In bivariate analyses, the odds of central recurrence were significantly higher at all three locations when the internal scar height was <4.5 mm compared to higher scars. In multivariate analyses, central scar height <4.5 mm and severe baseline trichiasis were independently associated with central postoperative trichiasis. CONCLUSION: Internal scar height <4.5 mm measured 1 year after surgery is more likely to be associated with postoperative trichiasis. Given these findings and the current World Health Organization recommendation for an incision height of 3.0 mm, further study into optimum incision height to minimize postoperative trichiasis is warranted.