Changes in optic nerve head and macula optical coherence tomography angiography parameters before and after trabeculectomy

Abstract

Purpose To evaluate the effects of lowering intraocular pressure (IOP) on foveal avascular zone (FAZ), peripapillary and macular vessel density (VD) by optical coherence tomography angiography (OCTA) in patients with open angle glaucoma after trabeculectomy. Study design Prospective study Methods Twenty eyes of 20 patients with primary open angle glaucoma (POAG) or exfoliation glaucoma (EG) who were followed up to six months and underwent trabeculectomy were included in our study. OCTA, AngioVue (Optovue Inc.) software was used to analyse the FAZ, peripapillary VD, macular superficial capillary plexus (SCP) and deep capillary plexus (DCP) VD. The parameters of the preoperative and postoperative controls were compared statistically. Results Twelve of the patients (60%) had POAG and eight (40%) had EG. Mean IOP measured was 22.4±2.4 mmHg preoperatively and 14.9±2.4 mmHg in the postoperative sixth month (p <0.001). There were no significant changes in OCTA optic disc and macular SCP VD values at the end of the sixth month. In macular DCP parameters; whole image VD (WI-VD), foveal VD (F-VD), parafoveal VD (PAF-VD) and perifoveal VD (PEF-VD) values increased statistically (p=0.003; p=0.026; p=0.006; p=0.004). There was a statistically significant decrease in FAZ area (FAZ-A) and FAZ perimeter (FAZ-P); and a significant increase was found in foveal density values (FD) (p=0.026; p=0.049; p=0.005). Conclusions We found that reducing IOP by trabeculectomy did not affect the microcirculation of the peripapillary region and macular SCP, while there was a significant increase in the DCP parameters of the macular region.

Comparison between open-angle glaucoma and angle-closure glaucoma regarding the short-term optic disc vessel density changes after trabeculectomy

“…Our patients are significantly younger than others. This study’s mean age was 56.25 ± 11.37 years, whereas the mean ages in other studies were 66, 63.8 ± 5.97, and 61.1 ± 14.5 for Lommatzsch et al [ 7 ], Güngör et al [ 1 ], and Zéboulon et al [ 4 ], respectively. The type of surgery may also lead to this discrepancy (Zéboulon et al use non-penetrating glaucoma surgery).…”

“…However, Lommatzsch et al [ 7 ], Güngör et al [ 1 ], and Zéboulon et al [ 4 ] reported a non significant change in optic disc VD following surgery to reduce IOP. The discrepancy in results may be due to age differences between patients.…”

“…Glaucoma is a leading cause of permanent blindness in both developed and developing countries. It is an optic neuropathy characterized by retinal ganglion cell axon degeneration, resulting in visual field loss due to progressive optic nerve damage [ 1 ].…”

The Preserflo MicroShunt Affects Microvascular Flow Density in Optical Coherence Tomography Angiography

“…The Preserflo MicroShunt has been shown to effectively lower IOP in glaucoma patients during long-term follow-up, irrespective of glaucoma subtype [5][6][7][29][30][31][32]. Recent studies have identified changes in retinal microvasculature related to IOP-lowering surgery in glaucoma patients [19][20][21][22]33]. This study represents the first trial to investigate changes in retinal FD in glaucoma patients related to treatment with the Preserflo Mi-croShunt.…”

“…Studies using optical coherence tomography angiography (OCTA), a new imaging technology that allows for the quantification of retinal microvasculature [11], have identified distinct changes in in glaucoma patients [12][13][14][15][16][17][18] and after IOP lowering surgery [19][20][21][22][23][24]. Bridging the gap between mechanical and vascular theories, these studies highlight the need for a comprehensive understanding of microvascular alterations attributed to less invasive glaucoma surgeries, particularly those involving devices like the Preserflo MicroShunt.…”