Changes of retinal vascular diameters after use of topical prostglandin analogues in vivo

Purpose : To evaluate the reliability of vessel caliber measurement methods and changes in retinal vessel diameter after the use of prostaglandin analogues (PGAs) in normal-tension glaucoma (NTG) patients. Materials and methods : This study included 118 NTG patients without vascular disease who were treated with single-agent PGs for 6 months or more. All subjects underwent a detailed glaucoma evaluation. We randomly chose 30 subjects to calculate reproducibility. After measuring each temporal arteriolar (TRAD) and venular diameter (TRVD) and their ratio (AVR) with computer-assisted imaging software, we divided the subjects according to the type of PGA (Tafluprost, Latanoprost, Travoprost, or Bimatoprost), and compared measurement values before and 1 month and 6 months after use of each PGA. Results : The representative values of the intra-photographic reproducibility of the measurements, the intraclass correlation coefficients, were above 0.993. No significant difference was observed at baseline in the mean TRAD and TRVD between the PGA groups. There were no significant changes in AVR before and after use of any PGs. Changes in TRAD and TRVD were not significantly different between groups. Conclusion : Our method to assess retinal vessel calibers showed high reliability, but PGAs did not induce vascular diameter dilation in vivo .