Epidural hematoma associated with a closed capsule in the tumor cavity: illustrative case.

Background: The formation of a tumor bed cyst (TBC) is an infrequent complication that can occur following surgery for brain glioma. In this case report, the authors present the first documented occurrence of TBC associated with a postoperative epidural hematoma in a patient who underwent glioma surgery.

Observations: A 48-year-old right-handed male with right frontal lobe glioma underwent surgery, and an epidural hematoma was detected on CT 2 hours postcraniotomy. Subsequently, the patient exhibited progressive deterioration of consciousness. Reassessment via CT revealed no significant increase in the epidural hematoma size; however, there was evidence of a TBC within the cavity and aggravated peripheral edema. An urgent evacuation procedure was performed to remove the epidural hematoma, accompanied by an external dura opening to address the TBC. This resulted in a jet overflow of cyst fluid and a rapid reduction in tumor cavity size. After the patient regained consciousness from anesthesia, he exhibited normal motor function and maintained a lucid state of mind.

Lessons: The presence of epidural hematoma can contribute to the formation of a TBC. During reoperation for epidural hematoma removal, the compressive effect of the TBC went unnoticed, leading to its nontreatment. https://thejns.org/doi/10.3171/CASE24899.