A polyp can result from a single night of screaming at a ball game or shouting at a concert.

Surgery may be the best option, especially if the polyp is being fed by a blood vessel that can be identified and removed. Afterwards, speech therapy is used to modify behavior and promote healing of the tissue, as well as stretch the vocal folds.

Pain, if there is any, is usually felt as tension in the neck or around the Adam's apple. Therapy includes getting rid of the muscle tension from the body's effort to close the gap in the vocal folds.

Unexplained hoarseness that lasts more than two weeks begs for a visit to an ear, nose and throat doctor, a specialty called otolaryngology. The same with vocal fatigue. Any persistent change in a voice should trigger a doctor's visit.

Sometimes acid reflux changes a voice. That's usually treated with medication and a few speech therapy sessions.

Laryngeal cancer requires surgery. While it's rare, it's important to make sure "nothing sinister is going on," Tanner says.

Otolaryngologist Dr. Marshall E. Smith specializes in voice. Removal of a polyp or nodule usually means resting the voice for 10 to 14 days, then easing back into speech. It may take several weeks or a couple of months before singing is possible. Surgery will improve a paralyzed vocal cord right away.

Even nonsmokers can develop cancer of the larynx, which may mean removal of part of the vocal cord. "Usually we can remove it and leave them able to speak," Smith says.

He sometimes injects the vocal cord with materials to help correct a problem. Botox helps spasmodic dysphonia by relaxing the muscles and allowing someone to speak more easily, for instance.

Smith also sees patients who have neurological problems that affect the voice and throat, such as the tremor that accompanies Parkinson's disease.

Johnson had breast cancer and believes the chemotherapy played a role in her vocal disorder. She got a sinus infection that "blew up," and she coughed for four days. When she finally stopped, she says, her voice was different. Months later, it was still bad.

Smith found a hemorrhagic polyp on one side, a reactive nodule on the other. "For a singer, that's doom," she says. At the time, she was beginning to do a lot of voice-over work. She was terrified of surgery, which has some risk. In vocal therapy, she learned "really useful exercises that I still do." When her voice fogs over, the exercises clear it right up. "It's sort of magical," she says.

Not being able to sing around the house or in the car was "like not belonging to myself anymore," she says. She's back.