Methods of using the alpha-2-adrenergic receptor agonist of Formula I:for improving vision such as in the treatment of ocular conditions such as presbyopia, poor night vision, visual glare, visual starbursts, visual halos, and some forms of myopia (e.g. night myopia) are described.所描述者係使用式I之α2腎上腺素受體促效劑之方法:其係用於在諸如眼部病況治療中改善視力,該等眼部病況諸如老花眼、不良夜間視力、視覺眩光、視覺星芒、視覺光暈、以及一些形式的近視(例如夜間近視)。