ARDMS, incorporated in June 1975, is an independent, nonprofit organization that administers examinations and awards credenti ... als in the areas of diagnostic medical sonography, diagnostic cardiac sonography, vascular technology and musculoskeletal sonography. ARDMS offers these credentials: RDMS® – Registered Diagnostic Medical Sonographer® RDCS® – Registered Diagnostic Cardiac Sonographer® RVT® – Registered Vascular Technologist® RMSKS™ – Registered Musculoskeletal™ Sonographer read more