Quantitative Analysis of Retinal and Choroidal Microvascular Changes After Endonasal Endoscopic Pituitary Adenoma Resection: An OCTA Study.

Background: This study used swept-source optical coherence tomography angiography (SS-OCTA) to compare retinal and choroidal vascular parameter changes before and after transsphenoidal surgery in pituitary adenoma (PA) patients, and to compare these changes with healthy controls, in order to evaluate its predictive value for visual recovery and determine the optimal timing for surgery.

Methods: 23 PA patients (46 eyes) and 25 healthy volunteers (50 eyes) were included. The PA group was followed up at 1 week and 1 month postoperatively. Retinal and choroidal parameters in the macula(M) area and optic nerve head(ONH) area were assessed, including thickness(T), volume(V), vascular flow density (VFD), foveal avascular zone (FAZ), choroidal vascular volume (CVV) and choroidal vascular index (CVI).

Results: Comparison of retinal and choroidal morphology and blood flow between the case group and the control group showed significant increases in the deep capillary plexus (DCP) thickness and volume in the macula. The superficial capillary plexus (SCP) thickness, volume, large and medium choroidal vessels (LMCV) CVI (p = 0.032) in the optic disc area, as well as all indicators of the FAZ were significantly reduced. Compared to preoperative values, a week postoperatively, SCP-T and SCP-V in the optic disc area, and DCP FAZ perimeter all significantly decreased, while SCP VFD in the foveal avascular zone within 300 μm (FAZ300) significantly increased (p = 0.047). Compared to preoperative values, 1 month postoperatively, LMCV choroidal matrix density (CSI), CVI (p = 0.022) and DCP-T in the optic nerve area significantly decreased, while SCP-FAZ300 significantly increased (p = 0.0282). Tumor size was the most important factor affecting retinal and choroidal parameters.

Conclusions: The SCP-T, CSI, CVI, and other parameters in PA patients were significantly lower compared to healthy controls. These parameters further decreased after decompression surgery, likely due to secondary changes from optic nerve atrophy caused by tumor compression. The continulous improvement of SCP foveal avascular zone within 300 μm(FAZ300) may be related to the recovery of blood flow after the decompression, as the macular cells remain intact. These parameters-SCP-FAZ300, LMCV-CVI/CSI, and SCP-ONH T/V-collectively quantify postoperative visual acuity(VA)and visual field(VF) outcomes and guide surgical timing selection.These findings suggest that PA patients require earlier screening and treatment, and OCTA can serve as an optimal non-invasive evaluation tool.