Extremely rare brain cyst prevents outflow of spinal fluid from your brain

Doctors told a 68-year-old woman her brain was one in a million and while the finding was anything but welcome, she knows the experts who identified her colloid cyst likely save her life.

From a visit one day to the operation room the next, Northwestern Medicine Neurosurgeon Dr. Stephen Magill discovered the a cyst on Leslie Fenton Pera’s brain that most people have about one in a million chance of getting.

“I trained at one of the biggest neurosurgery programs in the country, and I think in training and in practice you see them about once a year,” Dr. Magill said.

The cyst is called a colloid cyst, the distinctive anomaly likely formed at birth.

“This is basically a fluid-filled structure like a balloon that’s effectively obstructing the outflow of your spinal fluid from your brain,” Northwestern Medicine Neuroradiologist Dr. Alexander Korutz said.

While the cyst grew, it put pressure on Pera’s brain, on top of significant motor and cognitive deficits.

“She wasn’t keeping up, she wasn’t slurring her speech, but it was clearly slower than I was accustomed to hearing from her, so there was clearly something wrong going on. I wasn’t quite sure what,” Mark Pera, Leslie’s husband, said.

“Trouble walking, headaches, blurry vision, sometimes people have drop attacks where their legs give out from underneath them, confusion, sometimes memory problems,” Dr. Magill said.

For Leslie, there was another strange sign of trouble.

“I did notice several days before that my handwriting had become completely illegible and my signature, which is pretty specific did not look like me anymore and it’s not just age,” she said.

Working through a one-inch incision in the skull, Dr. Magill first placed a plastic tube to separate the folds of Leslie’s brain and place his instruments. The approach helps protect the delicate area that controls memory formation.

Three months after her surgery, the fluid in Leslie’s brain has returned to normal.

Doctors say the majority of patients with colloid cysts may never require surgery. In Leslie’s case, since fluid buildup was so great, surgeons had to intervene.

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