부산대학교 도서관

Highlights * Timolol decreased outflow facility in healthy human eyes. * This effect was greater in eyes with higher baseline outflow facility. * Older age was associated with lower outflow facility. Purpose Hyposecretion of aqueous humor has been postulated to adversely affect the health of the trabecular meshwork and outflow resistance. However, the effect of medications that reduce aqueous humor production on outflow facility in living human eyes is unclear. This study evaluated the effect of timolol, an aqueous humor flow suppressant, on outflow facility in healthy eyes. Design Prospective, before-and-after study. Methods In a multicenter study, 113 healthy participants over 40 years of age were included. Intraocular pressure (IOP) was measured with the participant in the sitting position by using a pneumatonometer. The outflow facility was measured with the participant in the supine position by 2-minute pneumatonography. After participants self-administered drops of timolol 0.5% for 1 week, twice daily in each eye, both measurements were repeated. Results Mean IOP decreased from 15.1 [plus or minus] 3.0 mm Hg at baseline to 12.4 [plus or minus] 2.4 mm Hg (P < 0.001) after 1 week of timolol use. Mean outflow facility decreased from 0.23 [plus or minus] 0.08 [mu]L/min/mm Hg at baseline to 0.18 [plus or minus] 0.08 [mu]L/min/mm Hg (P < 0.001) after timolol. The change in outflow facility was negatively correlated with baseline outflow facility (r = -0.51; P < 0.001). Conclusions Timolol reduces outflow facility in healthy human eyes, and this effect is greater in eyes with higher baseline outflow facility. This phenomenon may be related to reduced aqueous humor flow, but the precise mechanism remains to be determined.