Eyelid Blink Characteristics in Patients with Ptosis Assessed Using Cellphone Camera before and after Levator Resection

Purpose: To compare the eyelid blink characteristics of patients with ptosis assessed using a cellphone camera before and after levator resection. Metbods: In this prospective study, pictures and videos of eyelid blinking were obtained from 40 eyes (20 patients with ptosis) at a margin reflex distance 1 (MRD1) of 3.0 mm or less before and 1 month after levator resection. MRD1, palpebral fissure height (PFH), levator function, inter-blink interval, and blink duration, rate, and velocity were measured. The patients were also divided into those aged < 70 or >= 70. Results: MRD1, PFH, and blink velocity increased, and blink duration decreased, after levator resection. In the ptosis group aged less than 70 years, the levator function and blink velocity increased preoperatively, while MRD1, PFH, levator function, and blink velocity increased postoperatively. The blink velocity showed a positive correlation with MRD1 and PFH. Conclusions: Although no significant changes were observed in levator function postoperatively, the blink velocity increased significantly. Blink velocity may be useful for the evaluation of ptosis and as an indirect measure of levator function.