Abstract
Purpose :
To correlate the tube length, tip-endothelium distance and anterior chamber (AC) entrance angle with endothelial cell density (ECD) in patients with a glaucoma drainage device (GDD).
Methods :
Prospective and observational study that includes 20 eyes of 20 patients that underwent GDD. ECD was measured with specular microscopy at baseline, postoperative month-1, and month-3. Anterior segment OCT (AS-OCT) to evaluate tube position was performed at month-3. A Pearson correlation coefficient (r) was obtained between the tube length and distance from the tip of the tube to the endothelium. The Spearman test was employed for non-normal distributed data.
Results :
Mean patient age was 53.52+/-15.6 years.The most common diagnosis were neovascular glaucoma(54%), trauma associated glaucoma(16.6%), and primary open angle glaucoma(16.6%). Preoperative mean endothelial cell count(ECC) was 1859.7+/- 530.27 cells/mm2. Mean endothelial cell loss(ECL) at postoperative month-1 and month-3 was 54.04+/-131.4 cells/mm2(P = 0.203) and 87.63+/-189.1 cells/mm2(P = 0.0002) respectively. We found positive correlation between tube-endothelium distance and the angle of entrance into the AC with ECL at month-1 and month-3 follow up. No correlation was found with the tube length.
Conclusions :
We found significant decrease in corneal ECC in eyes with GDD at one and three month follow up periods. A significant inverse correlation was evidenced between tube-to-endothelium distance and ECL, where the shorter the distance, a higher the cell loss was verified. Tube length was not associated to significant ECL, it seems it is not necessary to shorten a tube in order to prevent ECL. There was a statistical significant ECL according to the mean tube entry angle to the AC. We found that the shorter the angle of entrance to the AC the greater is the ECL.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.