Structural Changes in the Optic Disc and Macula Detected by Swept-Source Optical Coherence Tomography After Surgical Intraocular Pressure Reduction in Patients with Open-Angle Glaucoma

Roberto Vessani, Thalyta Frota, Gabriella Shigetomi, Priscila Correa, Eduardo B Mariottoni, Ivan Tavares Department of Ophthalmology and Visual Sciences, Paulista School of Medicine, São Paulo Hospital, Federal University of São Paulo, São Paulo, BrazilCorrespondence: Roberto VessaniFederal University of São Paulo, Rua Pará 222, Apto 92, São Paulo, 01243020, BrazilTel +55 1132370707Email rmvessani@gmail.comPurpose: To evaluate the magnitude of change in optic disc, peripapillary retinal nerve fiber layer (RNFL) and macular parameters measured by swept-source optical coherence tomography (SS-OCT) in glaucomatous eyes after filtration surgery, and to determine any possible relationship between these measurements and baseline factors.Patients and Methods: This multicenter, prospective, consecutive observational study included patients with open-angle glaucoma who required glaucoma filtering surgery (surgical group, 29 eyes) and those with stable disease (control group, 25 eyes). Patients from the surgical group underwent measurement of optic disc, peripapillary retinal nerve fiber layer (RNFL) and macular parameters before and after surgery.Results: In the surgical group, there was a significant increase in rim area and a significant decrease in the linear cup/disc ratio, vertical cup/disc ratio and cup volume 1 and 2 months postoperatively (p 0.05). Furthermore, significant increases in macular parameters were observed until 2 months after surgery (p< 0.05). No significant changes were observed for all SS-OCT measurements in the control group. There was a significant correlation between the magnitude of the structural measurements change and the IOP reduction for two topographic parameters (rim area and linear cup-disc ratio) and macular average thickness 1 month and 2 months postoperatively.Conclusion: In open-angle glaucoma patients submitted to surgical IOP reductions, improvements in topographic and macular OCT parameters measured by SS-OCT were observed for at least 2 months.Keywords: filtering surgery, intraocular pressure, optic disc, macula, optical coherence tomograph