Tinnitus that's continuous, steady, and high-pitched (the most common type) generally indicates a problem in the auditory system and requires hearing tests conducted by an audiologist. Pulsatile tinnitus calls for a medical evaluation, especially if the noise is frequent or constant. MRI or CT imaging may be needed to check for a tumor or blood vessel abnormality.
^ McCombe A, Baguley D, Coles R, McKenna L, McKinney C, Windle-Taylor P (2001). "Guidelines for the grading of tinnitus severity: the results of a working group commissioned by the British Association of Otolaryngologists, Head and Neck Surgeons, 1999". Clinical Otolaryngology and Allied Sciences. 26 (5): 388–93. doi:10.1046/j.1365-2273.2001.00490.x. PMID 11678946. Archived (PDF) from the original on 2017-09-24.