Is Post-Surgical Fever Normal After Moyamoya Surgery?

Experiencing a fever after Moyamoya surgery is not considered normal, but it is not uncommon. While any postoperative temperature elevation should be taken seriously, understanding the underlying causes is crucial for proper diagnosis and effective treatment. Most fevers following neurosurgical procedures can be managed successfully when identified early and addressed appropriately.

Common Causes of Fever After Moyamoya Surgery

Early Postoperative Fever (Within First 48 Hours)

Non-infectious inflammatory response is one of the most frequent reasons for mild to moderate fever (below 38°C) in the immediate days after surgery. This type of fever typically arises due to the body's natural reaction to surgical trauma, tissue manipulation, or absorption of blood products around the surgical site. It is often self-limiting and resolves within a day or two without specific medical intervention.

In such cases, patients may benefit from supportive care measures, including hydration, rest, and physical cooling techniques like cool compresses or adjusting room temperature. Medications such as acetaminophen (paracetamol) may also be administered under medical supervision to help regulate body temperature. Importantly, if no other signs of infection are present—such as chills, rapid heart rate, or mental confusion—this form of fever is generally not a cause for alarm.

Late-Onset Fever (3–5 Days Post-Surgery)

Fever that develops beyond the third day after surgery, especially when reaching temperatures of 39°C or higher, warrants careful evaluation. At this stage, infection becomes a primary concern. Two major possibilities must be ruled out: surgical site infection and central nervous system (CNS) infection, such as meningitis or intracranial abscess.

To assess for surgical wound infection, clinicians examine the incision site for redness, swelling, warmth, pain, or discharge. Any purulent drainage should be cultured to identify potential pathogens. Prompt antibiotic therapy based on culture results can prevent complications and promote healing.

For suspected intracranial infection, neurological symptoms become critical indicators. These include neck stiffness (nuchal rigidity), photophobia, altered mental status, headache, nausea, or vomiting. A lumbar puncture may be performed to analyze cerebrospinal fluid (CSF) for changes in cell count, protein levels, glucose concentration, and presence of bacteria or other microorganisms. Imaging studies such as CT or MRI might also be used to detect abscesses or inflammation within the brain.

When to Seek Medical Attention

Persistent or high-grade fever, especially when accompanied by neurological deterioration or systemic signs of illness, requires immediate medical attention. Delayed diagnosis of CNS infections can lead to severe consequences, including seizures, cognitive deficits, or long-term disability.

Patients and caregivers should maintain close communication with the neurosurgical team during recovery. Regular follow-ups, adherence to prescribed medications, and vigilant monitoring of vital signs are essential components of a safe postoperative course.

Conclusion: Recovery Is Possible With Proper Care

While fever after Moyamoya surgery is not normal, it doesn't always indicate a serious complication. By identifying the root cause—whether inflammatory or infectious—healthcare providers can implement targeted treatments that support recovery. With timely intervention, most patients experience resolution of symptoms and continue toward full rehabilitation. Early detection, accurate diagnosis, and proactive management remain key to ensuring optimal outcomes after complex neurovascular procedures.