Abstract
Purpose :
To evaluate quantitative change in the foveal avascular zone (FAZ) area following glaucoma surgery using swept-source optical coherence tomography angiography (SS-OCTA) systems.
Methods :
We enrolled primary open angle glaucoma patients who underwent surgery to reduce intraocular pressure from April 2018 to September 2018. Two masked examiners reviewed image quality and excluded images that did not fulfill our image criteria. After excluding seven eyes for which images before or after surgery were blurred, 29 eyes in 23 patients (nine men, 14 women) were analyzed. The number of eyes undergoing various surgeries was as follows: two eyes underwent trabeculectomy, 13 eyes underwent treatment using Ex-PRESS, seven eyes underwent microhook trabeculotomy, four eyes were treated using a trabectome, one eye underwent Ahmed valve implantation, and two eyes underwent needling.
Results :
Patients were aged 65.1 ± 12.0 years (mean ± standard deviation), and the intraocular pressure value significantly decreased from 21.9 ± 11.1 mmHg preoperatively to 10.3 ± 3.2 mmHg postoperatively (p<0.001, paired t-test). The FAZ area was significantly reduced to 0.309 ± 0.122 mm2 (0.396 ± 0.140 mm2 after ocular axis correction) from 0.338 ± 0.143 mm2 preoperatively (0.434 ± 0.168 mm2 after ocular axis correction) (p<0.001, paired t-test). A proportion of the retinal blood vessels of the macular region that could not be confirmed preoperatively was drawn postoperatively, and the FAZ area had been reduced.
Conclusions :
The FAZ area imaged using SS-OCTA was significantly smaller after glaucoma surgery. It was suggested that the macular capillary retinal hemodynamics change with the reduction in intraocular pressure due to glaucoma surgery.
This abstract was presented at the 2019 ARVO Imaging in the Eye Conference, held in Vancouver, Canada, April 26-27, 2019.