A Comparative Study of the Water Drinking Test in Eyes with Open-Angle Glaucoma and Prior Trabeculectomy or Tube Shunt

摘要

?Purpose?To compare the intraocular pressure (IOP) response after the water drinking test (WDT) in patients who have undergone trabeculectomy or tube shunt surgery. ?Methods?We prospectively studied 40 eyes of 34 open-angle glaucoma subjects who had undergone trabeculectomy (n= 20) or tube shunt surgery (n= 20). Both groups were matched by IOP range and by number of topical antiglaucoma medications used. After a baseline IOP assessment, subjects drank 10ml water/kg body weight over 15 minutes. IOP was then measured with Goldman tonometer every 15 minutes over a one-hour period. Outcomes measures were IOP peak, fluctuation, mean and range. ?Results?There were no significant differences in baseline demographics, baseline clinical characteristics or IOP changes during the WDT between the two surgical procedure groups. In the trabeculectomy and tube shunt groups, Peak IOP was 16.25±5.55 and 16.15±5.36 mmHg, respectively (P=0.8294); IOP fluctuation (IOP max- IOP baseline)was 3.95±2.17 and 3.6±2.23 mmHg (P=0.6432) and IOP range 2.78±1.56 and 2.8±1.47 mmHg (P=1.00). When IOP fluctuation associations were studied (Wilcoxon test and Multivariable linear regression), the use of systemic antihypertensive blood pressure medication was associated with approximately 2 mmHg increase in IOP fluctuation. ?Conclusions?Subjects who had undergone either trabeculectomy or tube shunt surgery showed a similar IOP response to the WDT fluid challenge. Subjects using systemic blood pressure lowering medications experienced significantly higher IOP fluctuation during the test. ? Keywords: 464 clinical (human) or epidemiologic studies: risk factor assessment ? 633 outflow: trabecular meshwork ?.