- Department of Neurosurgery, Post Graduate Institute of Medical education and Research, Chandigarh, India
- Department of Pathology, Post Graduate Institute of Medical education and Research, Chandigarh, India
Department of Neurosurgery, Post Graduate Institute of Medical education and Research, Chandigarh, India
DOI:10.4103/2152-7806.139610Copyright: © 2014 Savardekar A. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
How to cite this article: Savardekar A, Chatterjee D, Chatterjee D, Dhandapani S, Mohindra S, Salunke P. Totally extradural spinal en plaque meningiomas – Diagnostic dilemmas and treatment strategies. Surg Neurol Int 28-Aug-2014;5:
How to cite this URL: Savardekar A, Chatterjee D, Chatterjee D, Dhandapani S, Mohindra S, Salunke P. Totally extradural spinal en plaque meningiomas – Diagnostic dilemmas and treatment strategies. Surg Neurol Int 28-Aug-2014;5:. Available from: http://sni.wpengine.com/surgicalint_articles/totally-extradural-spinal-en-plaque-meningiomas-diagnostic-dilemmas-and-treatment-strategies/
Background:Meningiomas are the second most common intraspinal tumors, constituting ~25% of all intraspinal tumors; however, in the context of extradural spinal lesions, the diagnosis of meningioma is an uncommon one. Purely extradural spinal meningiomas, especially of the en plaque variety, frequently mimic metastatic disease and may result in inadequate therapy.
Case Description:We report two cases of totally extradural en-plaque meningiomas of the spine, one each in the cervical and dorsal spine. We present the significant diagnostic dilemmas posed by these cases and discuss the pathogenesis, treatment strategies, and long-term behavior of these uncommon lesions.
Conclusion:Attention needs to be drawn to this dangerous preoperative and intraoperative misinterpretation. Intraoperative histopathology support for correct identification, gross total resection at surgery, inclusion of a durotomy to rule out intradural extension, and long-term follow-up are cornerstones for successful management of totally extradural en plaque spinal meningiomas.
Keywords: En plaque meningiomas, extradural spinal lesions, spinal meningiomas
Meningiomas account for 25% of all intraspinal neoplasms and are the second most common primary intraspinal tumor.[
Clinical and radiological presentation
A 35-year-old female presented with the chief complaints of neck pain, progressive spastic quadriparesis, and decreased sensations below the spinal level of C7. Magnetic resonance imaging (MRI) revealed an extradural en plaque lesion extending from C3 to C6 vertebral levels and invading the C4 and C5 lateral spinous processes, along with encasement of the vertebral artery traversing the C4 and C5 transverse (vertebral) foramina. The lesion was iso- to hypointense on T1-weighted as well as T2-weighted MR images and showed intense contrast enhancement [
MRI findings in Case 1, showing an extradural lesion extending from C3 to C6 vertebral levels. The lesion appears isointense on T1-weighted images [(a) axial, (e) sagittal], hyperintense on T2-weighted images [(b) axial, (f) sagittal], and exhibits intense enhancement on contrast administration [(c) axial, (g) sagittal]. Postoperative contrast-enhanced MRI [(d) axial, (h) sagittal] at 1 year follow-up showing small residue laterally on the left side, encircling the vertebral artery without any compression on the dural sac
The lesion was explored through C3-C6 hemilaminectomy. Intraoperative findings were that of a firm, fleshy, highly vascular tumor, and frozen section histopathology revealed meningothelial meningioma. In view of the benign pathology at hand, near-total excision of the tumor was achieved at surgery, leaving behind the part encasing the vertebral artery.
The patient had complete resolution of symptoms and follow-up radiology at 1 year showed small residue in the region of the lateral process encircling the vertebral artery, but without any dural compression [Figure
Clinical and radiological presentation
A 23-year-old female presented with spastic paraplegia and bowel and bladder involvement of 7 days duration. This was preceded by pain in the dorsal spine, radiating to both lower limbs for 2 months, and progressive weakness and spasticity in the lower limbs for 2 weeks. On examination, she had spastic quadriplegia and loss of all sensory modalities below the D5 dermatome. An urgent MRI of the thoracic spine showed an extradural en plaque spinal lesion located posterolateral to the spinal cord, pushing the dura anteriorly [
MRI findings in Case 2, showing an extradural lesion extending from D3 to D6 vertebral levels. The lesion is isointense on T1-weighted images [(a) axial, (e) sagittal], hyperintense on T2-weighted images [(b) axial, (f) sagittal], and intensely contrast enhancing [(c) axial, (g) sagittal]. Postoperative contrast-enhanced MRI [(d) axial, (h) sagittal] at 3 months follow-up shows gross total excision of the tumor
The patient underwent emergency D3-D5 laminectomy and decompression of the lesion. Intraoperative findings revealed a vascular and fleshy lesion present over the dura. Unfortunately, frozen section was not done at the first surgery, as this case was taken up as an emergency during the night. Histopathology was unequivocal for meningioma [
(a) Intraoperative image of the fleshy extradural meningioma (arrow) on the right side of the thecal sac, with the shining white dura (dashed arrow) under the tumor. (b) Photomicrograph (HE stain) showing a meningothelial meningioma arranged in syncytium and whorling pattern. Few psammoma bodies are also present
Although the patient improved after decompression, the benign nature of the pathology prompted us to re-explore with a wider left posterolateral approach and perform a total excision of the tumor. At surgery, the tumor could be peeled off the dura, enabling a total excision [
Meningiomas are the second most common intraspinal tumors. Approximately 80% occur in the thoracic spine, affecting women four times more often than men, with a peak incidence during the fifth to sixth decades of life.[
Several theories have been postulated to explain the pathogenesis of purely extradural meningiomas. Most likely, they arise from the ectopic or separated arachnoid tissue around the periradicular nerve root sleeve, where the spinal leptomeninx merges directly into the dura.[
Purely extradural spinal meningiomas, especially of the “en plaque” variety, may mimic metastatic disease.[
Once intraoperative diagnosis of meningioma is confirmed for an extradural spinal lesion, the surgeon should consider gross total resection of the tumor, including excision of the tumor extending into the bone or the paraspinal space. In order to gain access to the tumor on the ventral aspect of the spinal cord through the postero-lateral approach, wide lateral removal of the lamina, the pedicles and the facet joints may be necessary. Stabilization of the spine may be required, if the postero-lateral approach compromises the stability of the spine.[
Another important aspect to be considered is the treatment strategy for the underlying dura. The pathogenesis of extradural spinal meningiomas suggests that these tumors arise from the dural root sleeve and not from the external surface of the spinal dura. Consequently, as seen in both our cases, these tumors can be stripped off from the spinal dura, without the need to excise the dura.
Conflicting reports exist for the long-term prognosis of patients with extradural spinal meningiomas. While some authors have suggested that these tumors have a locally malignant course, others have shown these meningiomas to be benign.[
The prevalence of extradural meningiomas has been described as ranging between 3.3% and 21.4% of all spinal meningiomas.[
The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.
1. Frank BL, Harrop JS, Hanna A, Ratliff J. Cervical extradural meningioma: Case report and literature review. J Spinal Cord Med. 2008. 31: 302-5
2. Santiago BM, Rodeia P, Cunha E, Sa M. Extradural thoracic spinal meningioma. Neurol India. 2009. 57: 98-
3. Tuli J, Drzymalski DM, Lidov H, Tuli S. Extradural en-plaque spinal meningioma with intraneural invasion. World Neurosurg. 2012. 77: 202-
4. Yamada S, Kawai S, Yonezawa T, Masui K, Nishi N, Fujiwara K. Cervical extradural en-plaque meningioma. Neurol Med Chir (Tokyo). 2007. 47: 36-9
5. Zevgaridis D, Thomé C. Purely epidural spinal meningioma mimicking metastatic tumor: Case report and review of literature. Spine (Phila Pa 1976). 2002. 27: E403-5