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Published on: July 5, 2021
Mirror Meningioma at Foramen Magnum: A Management Challenge
Subhas Konar1, Shyamal C Bir1, Tanmoy Kumar Maiti1
1Department of Neurosurgery, Louisiana State University Health-Shreveport, Shreveport, Louisiana, USA.
Background:
Meningiomas of the foramen magnum are among the most challenging of all skull base lesions. Controversies continue regarding the most appropriate approach to this critical anatomic region. The authors report a first case in English literature about twin meningiomas arising from both sides of the ventrolateral dura at the foramen magnum.
Case Description:
Preoperative imaging showed a solitary mass engulfing the lower medulla. However, intraoperatively a twin mass was discovered. It encased the right side vertebral artery (VA) and abutted the left side. The unilateral far lateral transcondylar approach is not enough to resect both tumors at the same time. However, the far lateral transcondylar approach in both sides may compromise the stability and increase the risk of injury to either side of the neurovascular structures.
Conclusions:
We suggest that resection can be safely achieved via the unilateral far lateral transcondylar approach followed by Gamma Knife radiosurgery (GKRS) or a staged bilateral approach.
Insights
This study presents a rare case of twin meningiomas at the foramen magnum. A unilateral far lateral approach combined with Gamma Knife radiosurgery or a staged bilateral approach offers a safe resection strategy.
Area of Science:
- Neurosurgery
- Skull Base Surgery
- Oncology
Background:
- Foramen magnum meningiomas represent complex skull base lesions with ongoing debate regarding optimal surgical approaches.
- This report details the first documented case of twin meningiomas originating from bilateral ventrolateral dura at the foramen magnum.
Observation:
- Preoperative imaging suggested a single mass compressing the medulla.
- Intraoperative findings revealed a twin meningioma encasing the right vertebral artery and abutting the left.
- A standard unilateral far lateral transcondylar approach was insufficient for complete resection of both tumors.
Findings:
- Complete resection of bilateral foramen magnum twin meningiomas poses a surgical challenge due to proximity to neurovascular structures.
- The unilateral far lateral transcondylar approach, when combined with Gamma Knife radiosurgery, provides a viable option for managing these complex tumors.
- Alternatively, a staged bilateral approach may be considered for complete tumor removal.
Implications:
- This case highlights the importance of thorough intraoperative assessment for unexpected findings in skull base surgery.
- The described multimodal strategy (surgery + radiosurgery or staged surgery) offers a potential solution for challenging foramen magnum meningiomas.
- Further research into tailored surgical and adjuvant treatment strategies for complex foramen magnum lesions is warranted.
