Magnetic Resonance Spectroscopy Features of the Visual Pathways in Patients with Glaucoma.

The aim of the study was to investigate any metabolic changes on magnetic resonance spectroscopy (MRS) throughout the visual pathway of the brain in patients with glaucoma and a control group and correlate the results with clinical findings. A total of 87 patients were enrolled in the study, 30 healthy controls, 25 glaucoma, 16 suspected glaucoma (GS) and 16 ocular hypertension (OHT) patients. A single voxel MRS on TE 30 ms was performed by placing the volume of interest (VOI) on the corpus geniculatum laterale (CGL) and primary visual cortex (VC). Peak values of metabolites, such as N‑acetyl aspartate (NAA), creatine (Cr), choline (Cho) and Myo-inositol (Ins) were investigated on MRS. The MRS results were correlated with age, intraocular pressure (IOP), retinal nerve fiber length (RNFL), mean deviation (MD) and cup disk ratio (CD). The NAA values obtained from the CGL in glaucoma and GS cases were lower than the healthy control group. The Cho values at CGL in glaucoma were lower than GS and controls. There was a negative correlation between NAA values of the VC and CD in glaucoma cases. Additionally, there was a negative correlation between age and RNFL in both glaucoma and GS cases. The use of MRS can reveal neurodegeneration in CGL and VC in patients with glaucoma. Depiction of metabolic changes throughout the visual pathways via MRS will guide the treatment planning and follow-up in glaucoma and GS cases.