Chiari Malformation

Grand Rounds

When is Surgery Necessary?

Maria Blackburn

A 15-year-old white boy with short hair and freckles, wearing shorts and a dark colored, short-sleeved polo shirt, sitting on his kitchen counter. He is Chiari malformation patient Parker Riese.
Photo: Lindsey Dowell

When Jennifer Riese took her then 13-year-old son Parker to the pediatrician in February 2021, they expected the usual well-child visit: height and weight check, questions about sleeping and eating, a vaccination or two. But when the doctor saw low muscle tone in Parker’s legs and considered his fatigue and floppy gait, she referred him to a neurologist who ordered an MRI.

She wasn’t worried. “Why would I panic if I didn’t know what to panic about?” says Riese, an elementary school educator and mother of three from Acworth, Ga. “I trusted they would help us get to the bottom of this.”

Then she learned her son had Chiari malformation, a congenital structural abnormality affecting about 1 in 1,000 people. Parker’s skull was too small for his growing brain, and his compressed brainstem and cranial nerves were causing his fatigue, while a buildup of spinal fluid made a cyst (known as a syrinx) form in Parker’s spinal cord, which was affecting his gait. Now, Riese worried.

She joined a Facebook group for Chiari families and consulted a handful of pediatric neurosurgeons. Parker’s case was complicated, and she and her husband Michael had so many questions. Should Parker have surgery? And if so, should they schedule it now or wait to see if Parker’s pain and difficulty walking got worse? If they waited, could that put Parker at risk of paralysis if his condition worsened quickly? The parents she met online were supportive, but the neurosurgeons they talked to left them feeling unsure about how to proceed.

Then the Facebook group led the family to Dr. Jeffrey Greenfield (M.D. ’02), director of the Chiari CARE program in the Department of Neurological Surgery at Weill Cornell Medicine. Dr. Greenfield, an associate professor of neurological surgery, has treated thousands of patients with Chiari malformation in the last 13 years, many who’ve found him through social media. Only a quarter of those patients have required surgery — others might opt for pain management while remaining monitored for symptoms.

“Chiari is a niche that found me, and I love it,” Dr. Greenfield says. “It’s a mix between primary care and neurosurgery — you’re making decisions about improving someone’s quality of life, and the relationship with patients and families is paramount.”

Ten minutes into their first appointment in October 2021, the Rieses knew they had found the right person to treat Parker. “Dr. Greenfield’s passion for Chiari, his empathy for us as parents, and his treatment of Parker as if he was his only patient was what we were praying for,” Riese says. Together they discussed Parker’s case and decided to wait six to 12 months to get more images of Parker’s brain before scheduling surgery. When his condition declined four months after their first meeting, they decided it was time for Dr. Greenfield to perform surgery to alleviate the compression of Parker’s brain and restore the flow of cerebral spinal fluid.

Parker had one request when Dr. Greenfield saw him at NewYork-Presbyterian/Weill Cornell Medical Center on the morning of surgery in February 2022. “I want to go to the premiere of The Batman on March 4,” he said. It was an ambitious goal: The film screening was just nine days away.

During the four-hour surgery, Dr. Greenfield made an incision at the back of Parker’s head and removed a small piece of skull to relieve pressure on his brain. He then removed a piece of bone at the top of the spinal column to create more space. Then he opened the dura, the tissue encasing the brain and spinal cord, and sewed a patch for the brain fluid and cerebellum to expand into. With more room, the syrinx would slowly decompress, and Parker’s symptoms would improve.

Surgery went well, and Parker’s quick recovery, with little to no pain, led the hospital medical team to rename him “Batman Superstar.” Just like he hoped, he attended the premiere, pronouncing the movie, “Really good!”

Three months later, an MRI showed his syrinx had shrunk by 50 percent and the blockage of cerebral spinal fluid was gone. Parker had more energy, the burning pain in his back was gone, and his walking improved. This past summer, he went to camp, started training for high school tennis tryouts, and turned 15. “Parker is back to himself, thanks to Dr. Greenfield,” Riese says.

Dr. Greenfield keeps metrics like MRIs and other data to measure the success of the Chiari patients he sees. However, they aren’t all he considers important. “The metric we strive hardest to hit is that patients like Parker and his family are happy and doing well and thriving — that’s the one that matters most.”

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