Efficacy of the pedicle trapezius muscle flap for the multisurgical removal of pediatric posterior fossa anaplastic ependymoma

Objective Exceedingly refractory, pediatric anaplastic ependymoma in many cases requires multisurgical removal. The high risk of poor wound healing and CSF leakage especially at the posterior fossa make this tumor difficult to treat. Case A 9-year-old girl has had 4th ventricular anaplastic ependymoma since the age of 3. She experienced tumor removal 8 times including 4 posterior fossa craniotomies because tumors were disseminated not only to the posterior fossa but also to the cerebral hemispheres. She also underwent a dermal graft using a free flap. She experienced CSF leaks and meningitis frequently because the wound healing was poor. We performed a dermal flap closure using a pedicle trapezius muscle flap with a plastic surgeon when we performed the 5th tumor removal. Result We achieved complete wound closure in spite of broad deficiencies in subcutaneous and epidermal tissues. After that, recurrences of posterior fossa tumors presented within a short term, and tumor removal via an incision of a pedicle trapezius muscle flap was performed without recurrence of CSF leaks and meningitis. Discussion and conclusion For the first time, we are able to report on the efficacy of using the pedicle trapezius muscle flap for multisurgical removal of pediatric posterior fossa anaplastic ependymoma. The muscle flap was found to be effective because of the multiple surgeries expected, and the pedicle trapezius muscle flap was found to be resilient to multiple surgical procedures. Although advantageous, the dorsal scapular artery which is required for flap creation is actually difficult to harvest. Compared to a flee flap, the pedicle trapezius muscle flap maintains vascular supply. Furthermore, this technique has the possibility of being applied to defective dura mater closure that cannot be watertight due to multiple surgeries. However, it is very important to inform the patient’s family not only about the improved efficacy of surgery, but also to raise awareness on consequential cosmetic issues.