Researchers predict contralateral moyamoya disease progression after single-sided brain surgery

A team of researchers, led by Professors Bang Jae-seung and Lee Si-un from Seoul National University Bundang Hospital (SNUBH), recently published a study identifying the risk and predictors of moyamoya disease worsening in the contralateral brain following cerebrovascular surgery performed on only one side of the brain in patients with bilateral moyamoya disease.

Moyamoya disease is a condition characterized by the gradual narrowing and blockage of the main blood vessels supplying blood to the brain. It is crucial to treat and manage the disease aggressively, as prolonged inadequate blood supply to the brain can result in serious complications such as stroke and cerebral hemorrhage.

Moyamoya disease typically affects both sides of the brain, and its treatment often involves cerebrovascular anastomosis surgery. This procedure connects blood vessels outside the brain to those inside to improve cerebral blood flow. Generally, surgery is first performed on the side of the brain with the most severe symptoms, with the other side treated if necessary. However, there has been limited research on criteria to predict how the disease might progress in the contralateral brain after surgery on one side.

To evaluate the likelihood and risk factors of disease progression in the contralateral brain following surgery on one side in patients with bilateral moyamoya disease, the research team conducted a follow-up study. They tracked 174 patients who underwent cerebrovascular anastomosis surgery on one side of the brain for bilateral moyamoya disease at SNUBH between 2003 and 2022, with an average follow-up period of 45 months.

The results revealed that 57 of the 174 patients (approximately 32.8 percent) required additional cerebrovascular anastomosis surgery due to disease worsening in the contralateral brain, which had not undergone surgery during the observation period. The annualized progression rate to the contralateral brain was 7.7 percent, indicating that around 7 to 8 out of 100 patients may experience worsening contralateral brain lesions each year.

Notably, patients with a body mass index (BMI) of 25 or higher had a 12.1 percent annual risk of contralateral progression, compared to 4 percent in those with a BMI below 25. Based on these findings, the researchers emphasize that weight management played a critical role in controlling the progression of moyamoya disease. They recommend careful observation, proactive weight management, and long-term monitoring even after surgery.

“This is the first study to identify factors that predict disease progression in the contralateral brain after treating one side of the brain in patients with bilateral moyamoya disease,” said Professor Bang. “These findings will facilitate more personalized management and preventive strategies for high-risk patients.”

“By identifying an objective marker to predict disease progression, we have established a foundation for scientifically assessing the likelihood of Moyamoya disease worsening,” said Professor Lee. “We will continue our research to develop improved treatment options for patients.”

The findings were published in the Journal of Neurosurgery, an SCIE-ranked international journal widely regarded as an authoritative source in the field of neurosurgery.