Novel Drug Delivery Technique Via Retroject Device

The purpose of this study is to identify whether or not injection of a study drug (ethacrynic acid) using the investigational Retroject device is able to lower eye pressures in patients with advanced glaucoma. 20 patients with advanced glaucoma with visual acuity less than 20/200 and intraocular pressures (IOP) >20mmHg on maximum medical therapy will be asked to participate in the study. The first five patients will have the Retroject device placed over their eye for 30 seconds and then removed. Assuming no issues, then it will be placed on the eye for one minute. The second group of patients (3 total) will have the Retroject device placed on the eye and then an injection of ethacrynic acid into the episcleral vein. The third group of patients (12 total) will have the Retroject device placed on the eye and then will be randomized in a 2:1 ratio to receive either an ethacrynic acid injection or a balanced salt solution injection. All 20 patients will then return for intraocular pressure measurements on days 1, 2, 3, and 7 as well as 6 weeks after injection. In addition, the patients will undergo pre and post intervention corneal endothelial assessments (endothelial cell count, shape analysis, and pachymetry). Potential safety issues are unlikely and include bleeding, infection, pain, ototoxicity, or temporary or permanent loss of vision.