This patient has sensorineural hearing loss, which is the most common cause of continuous, high-pitched tinnitus. Sensorineural hearing loss results from decreased sound perception due to disorders of the cochlea or acoustic nerve. Risk factors include age (presbycusis), exposure to loud noise, and ototoxic medications. Given this patient's age, chronic and bilateral symptoms, past sound exposure, and difficulty hearing when background noise is present, sensorineural hearing loss is the most likely cause of his tinnitus. Evaluation for hearing loss in the office may be accomplished by the whispered voice test, in which the examiner stands at arm's length behind the patient and the patient occludes the untested ear canal. The examiner then whispers six sets of three letter or number combinations to the patient; failure to repeat at least three of the six sets correctly constitutes a positive result.

Acoustic neuroma (or vestibular schwannoma) is a Schwann cell–derived tumor that arises from the vestibular portion of cranial nerve VIII and may cause sensorineural hearing loss and tinnitus. However, acoustic neuromas are rarely bilateral or cause symmetric hearing loss, such as that seen in this patient, making this an unlikely diagnosis.

Meniere disease is typically characterized by the triad of sensorineural hearing loss, tinnitus, and vertigo. Although this patient has evidence of sensorineural hearing loss and tinnitus, which frequently accompany one another, he does not have vertigo. Therefore, Meniere disease is much less likely.

Otosclerosis is a cause of conductive hearing loss resulting from bony changes in the middle ear. Although usually also of progressive onset, otosclerosis results in loss of ability to hear low-pitched sounds without tinnitus. Conductive hearing loss can be distinguished in the office from sensorineural hearing loss by using the Weber and Rinne tests.