Quantitative Assessment of the Pupil: An Underrecognized Yet Important Factor Related to Orbital Blowout Fracture Repair

Abstract

Purpose: To investigate dynamic pupil changes after orbital blowout fracture repair. To compare postoperative changes in under photopic and mesopic pupil size and center position after orbital blowout fracture repair surgery. Methods: The study evaluated 19 eyes. Pupils were imaged for pupil size and center position before and 3 months after orbital blowout fracture repair surgery. Pupil size changes were measured, and the correlation between preoperative and postoperative pupil centroid shift was evaluated. Results: After repair, operative eyes exhibited a growth of 9.3% AE 8.6% in pupil size, and contralateral eyes showed a growth of 8.6% AE 8.2% (P ¼ 0.011, P ¼ 0.007). Similar findings were noted in mesopic conditions. Under mesopic conditions, the pupil of operative eyes in medial orbital wall fracture deviated 0.030 AE 0.019 mm towards the nasal side along the X-axis (P ¼ 0.031). The postoperative orbital floor fracture group demonstrated statistical significance at a spatial frequency of 5 (P ¼ 0.041). Conclusions: Orbital blowout fracture repair surgery affects pupil size and center position.