"That's odd," Cheryl thought. "I don't usually get headaches." But before long, she had unexplained headaches every day. Then she began having trouble hearing on the phone, a big inconvenience, given the frequent phone calls that went with her job as a management consultant. She also started feeling dizzy, as if she or her surroundings were spinning.

She made an appointment to see an otolaryngologist, a specialist in disorders related to the ear, nose and throat. Since she was having trouble hearing, she thought it best to see an expert in that field. And she knew that vertigo (the type of dizziness she experienced) can be related to ear problems as well.

In the ear doctor's office, an audiologist tested Cheryl's hearing, confirming that she had moderate to major hearing loss on the right side. What steps did the doctor take?

"He patted me on the knee and said, 'Go home and think happy thoughts; you've just listened to too much rock and roll music.'"

Annoyed, Cheryl replied, "Both ears listened to rock and roll music. Why am I not losing hearing on both sides?"

The doctor did not offer any answer and Cheryl went home. Before long, though, she was back in his office, reporting that her vertigo had gotten so overwhelming that she was afraid to drive or go to work. The doctor prescribed a medicine to counteract the dizziness and sent her home again.

Still worried, she talked with a friend, Ann, who was a registered nurse. Ann asked a key question: "Is the world spinning out there? Or are you spinning inside?" The unexpected question startled Cheryl, who replied that she was spinning inside. Ann suggested that the problem might be serious.

Cheryl called the doctor and asked that he do further testing. He declined to change his care plan, telling her to continue taking the anti-dizziness medicine and to come in a week later as previously scheduled for a routine follow-up appointment.

Instead, struck by Ann's concern, Cheryl made an appointment with a neurologist. After asking a number of questions and listening carefully to her description of her symptoms, the neurologist ordered an MRI. He called promptly with the results, saying, "I have good news and bad news." Cheryl asked for the bad news first.

"The bad news is that you have a brain tumor, and the good news is that I have just the right surgeon to help you."

Cheryl reported, "I was given two weeks to 'get my affairs in order,'" a shocking prospect for a previously healthy 50-year-old. Then she spent nine hours in the operating room having brain surgery to remove a tumor called a meningioma. The brain surgeon was successful in removing all of the mass. As Cheryl left the recovery room and was taken to the ICU, things were looking up.

She wasn't out of the woods yet, though. As she started to recover, she had new neurological symptoms. Six weeks later, a CT scan showed that an artery in her brain was bleeding, the result of a small accidental nick during the surgery whose effects took some time to show up in tests.

Cheryl explained, "Blood was pulsing across my brain, and it felt as though my arms and hands were on fire; it was excruciatingly painful and frightening." Another operation was needed to seal off the bleeding artery, after which Cheryl could finally start recovering from the trauma.

Some meningiomas are harmless. In Cheryl's case, the tumor would have continued to degrade her quality of life and eventually would have severely disabled and then killed her. Misdiagnosis is not simply an inconvenience; it can be deadly.

What can you do to prevent or address misdiagnosis? First, consider asking your doctor three questions suggested by Dr. Jerome Groopman: Do I have any symptoms that don't fit the diagnosis? What else could it be? Is it possible that I have two problems? Second, do a little research yourself; consider using a reputable resource such as the Mayo Clinic's Symptom Tracker at www.mayoclinic.org/symptom-checker/select-symptom/ITT-20009075. Third, don't hesitate to get a second opinion. Doing so may have saved Cheryl's life, and it may also save yours.