Quantitative Assessment Of The Pupil: An Underrecognized Yet Important Factor Related To Orbital Blowout Fracture Repair

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% +/- 8.6% in pupil size, and contralateral eyes showed a growth of 8.6% +/- 8.2% (P = 0.011, P = 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 +/- 0.019 mm towards the nasal side along the X-axis (P = 0.031). The postoperative orbital floor fracture group demonstrated statistical significance at a spatial frequency of 5 (P = 0.041). Conclusions: Orbital blowout fracture repair surgery affects pupil size and center position.