Gaynes Bruce I, Singa Ramesh M, Cao Ying
Department of Ophthalmology, Rush College of Medicine, Chicago, IL 60612, USA.
J Glaucoma. 2009 Feb;18(2):149-52. doi: 10.1097/IJG.0b013e3181753339.
To ascertain consequence of variability in drop volume obtained from multiuse topical ocular hypotensive products in terms of uniformity of product dosage.
Densitometric assessment of drop volume dispensed from 2 alternative bottle positions.
All except one product demonstrated a statistically significant difference in drop volume when administered at either a 45-degree or 90-degree bottle angle (Student t test, P<0.001). Product-specific drop volume ranged from a nadir of 22.36 microL to a high of 53.54 microL depending on bottle angle of administration. Deviation in drop dose was directly proportional to variability in drop volume. Variability in per drop dosage was conspicuous among products with a coefficient of variation from 1.49% to 15.91%. In accordance with drop volume, all products demonstrated a statistically significant difference in drop dose at 45-degree versus 90-degree administration angles. Drop volume was found unrelated to drop uniformity (Spearman r=0.01987 and P=0.9463).
Variability and lack of uniformity in drop dosage is clearly evident among select ocular hypotensive products and is related to angle of drop administration. Erratic dosage of topical ocular hypotensive therapy may contribute in part to therapeutic failure and/or toxicity.
根据产品剂量的均匀性，确定从多次使用的局部降眼压产品获得的滴液体积变化的影响。
对从2个不同瓶子位置挤出的滴液体积进行光密度评估。
除一种产品外，所有产品在以45度或90度瓶角给药时，滴液体积均显示出统计学上的显著差异（Student t检验，P<0.001）。根据给药的瓶角，特定产品的滴液体积范围从最低点22.36微升至高值53.54微升。滴剂量偏差与滴液体积变化成正比。在变异系数为1.49%至15.91%的产品中，每滴剂量的变化很明显。与滴液体积一致，所有产品在45度与90度给药角度下的滴剂量均显示出统计学上的显著差异。发现滴液体积与滴液均匀性无关（Spearman r=0.01987，P=0.9463）。
在某些降眼压产品中，滴剂量的变化和缺乏均匀性明显可见，并且与滴液给药角度有关。局部降眼压治疗的不稳定剂量可能部分导致治疗失败和/或毒性。
