Time-dependent Response of Eyelid Height with a Single Drop of 2.5% Phenylephrine in Korean Ptotic Patients

PURPOSE: We sought to investigate the temporal changes of eyelid height after phenylephrine instillation in Korean patients with and without ptosis to determine the time points of the first and maximum reactions. METHODS: The phenylephrine test was performed on 16 eyes of 12 ptotic patients (group I) and 24 eyes of 12 normal control subjects (group II) in our hospital between September 2017 and March 2018. One drop of 2.5% phenylephrine was instilled and the marginal reflex distance 1 (MRD1) was measured at 15 seconds before instillation and the following time points after instillation: at 15-second intervals for the initial 5 minutes and at 5-minute intervals until a total of 20 minutes was reached (i.e., at 10, 15, and 20 minutes). RESULTS: In group I patients, the first reaction appeared at 5 minutes (p = 0.034), while the maximum eyelid height after the first reaction was reached at 15 minutes (p = 0.025) and was maintained until 20 minutes. In group II subjects, the first reaction appeared at 5 minutes (p = 0.034), while the maximum eyelid height was reached at 10 minutes (p = 0.015) and was maintained until 20 minutes. There was no significant difference in the response of eyelid height based on time (p = 0.122) between the two groups. CONCLUSIONS: Our analysis of phenylephrine test results in Korean ptotic patients revealed a significant increase occurred in the eyelid height after 5 minutes; meanwhile, the maximum eyelid height was reached at 15 minutes and was maintained until 20 minutes after instillation.