 This is an observational cohort imaging study involving a single center recruiting patients from the prevalent conventional hemodialysis, peritoneal dialysis and CKD stage 4-5 population of London, Ontario, compared to healthy controls. Once recruited, participants will undergo a study session on a non-dialysis day for hemodialysis patients. This session will include symptom questionnaires, blood work, and an MRI study of the thigh detecting sodium content. The investigators aim is to characterize Na deposition in these different patient groups and analyze their association with biochemical markers, and uremic symptom severity. 