English doctors, who were performing a routine operation on a woman, made a surprising discovery when the patient had trouble regaining consciousness, London's Daily Mail reported.

Cara Prestidge had gone to University Hospital in Coventry, England for surgery on her uterus – but when she had problems waking up after the procedure, doctors immediately ordered a CT scan.

What they found was a brain tumor the size of a tennis ball. Surgeons immediately removed the massive growth.

“I have no doubt this operation saved her life,” said Dr. Amar Saxena, who performed the surgery. “I have been very pleasantly surprised by how she has recovered so quickly from a major operation on the brain.”

It took surgeons three-and-a-half hours to complete the operation. The tumor was not cancerous.

“I was in the right place at the right time,” Prestidge told the newspaper. “I’d suffered from bad headaches for years but just put it down to migraines. It was just completely unbelievable. I was on morphine at the time so it took a while to sink in, and I’m still not sure it has sunk in now.”

Prestidge had a meningioma, which is a type of tumor that develops from the membranes that surround your brain and spinal cord.

While the majority of these cases are non-cancerous, meningioma can be cancerous and most commonly occurs in women, according to the Mayo Clinic.

Symptoms include:

— Seizures

— Headaches that worsen with time

— Memory loss

— Changes in vision, such as seeing double or blurriness

— Hearing loss

— Weakness in your arms or legs

Meningioma is usually a very slow-growing tumor, so signs and symptoms may be subtle and gradually worsen over a long period of time, the Mayo Clinic said on its Web site.

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