Neuromonics is turning out to be the most effective treatment available for chronic tinnitus, but the cost — not covered by insurance — is prohibitive.

The intervention, called Neuromonics, retrains people to manage how they hear the internal sound. But it’s not covered by insurance and is expensive – about $4,500 for a device that resembles a portable music player and for sessions with an audiologist to tailor the treatment.

Teri Kim, 48, of Cary, N.C., started the therapy in August, and almost quit a month into it when she still hadn’t gotten relief from the high-pitched whine that has blared in her head for years. Then she gradually began having good days and even good weeks as the whine began to diminish.

“It was wonderful,” Kim said.

The therapy works on the finding that many cases of tinnitus (pronounced teh-NYE-tus or TIN-eh-tus) are produced inside the brain, not the ear.

Rebecca Price, an audiologist at Duke who provides the therapy,, said the internal sound is often accompanied by hearing loss. When the ear can no longer pick up a certain sound frequency, scientists theorize, the brain fills the void, causing a non-stop din.

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