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Neuroradiology Case of the Week

Case 290

Ashwani K. Sharma, MD and P-L Westesson, MD, PhD, DDS

Clinical Presentation: Patient is a 63-year-old male who presented with progressive quadriparesis for the past six months.

Imaging Findings: Imaging findings includes intradural extramedullary mass lesion, appearing isointense on T1 and T2 WI and showing uniform enhancement after intravenous contrast. Cystic component may be found. Associated bony changes like widening of the neural foramina or posterior scalloping of the vertebral body is to be noted.

Diagnosis: Cervical spinal canal meningioma

Discussion: Schwannoma and meningioma are the two most common intraspinal tumors [1]. Intraspinal schwannomas may be located in the spinal canal, or sometimes, may extend along the root to the extravertebral space through the intervertebral foramen and become dumbbell tumors [2]. In contrast, intraspinal meningiomas are usually located in the spinal canal, and do not extend through the intervertebral foramen [3]. Therefore, the schwannoma commonly appears as a spinal dumbbell tumor, however, rarely, the meningioma appears as a spinal dumbbell tumor.
     Meningiomas account for approximately 25% of all primary spinal cord tumors, with an incidence that varies depending on spinal level—decreasing in frequency from thoracic to cervical to lumbar levels [4].
     Pain is the most common symptom which may be radicular, funicular, or localized back pain. Significant weakness (paresis or plegia) and sensory loss (hypoesthesia, paresthesia, or anesthesia) are the next most common symptoms.
     The MRI findings that make it possible to distinguish benign from malignant tumors mainly include parameters such as tumor outline, invasive behavior, and edematous reactions. Characteristic signal intensity of spinal meningioma was found to be similar to that of the normal spinal cord on T1- and T2-weighted images. Spinal meningioma showed intense enhancement on MRI studies after intravenous injection of gadolinium-DTPA [5].
     Differential diagnosis for the extramedullary intradural mass lesion includes meningioma, schwannoma, neurofibroma, metastasis, dermoid/epidermoid, lipoma, paraganglioma and rarely ependymoma.
     Although the acceptable treatment method for spinal meningioma is total removal of the tumor by microsurgery, Mirimanoff, et al. suggested that radiotherapy should be considered as an adjunctive treatment after subtotal excision. Radiotherapy can also control unexcised or recurrent meningioma [6].

References:

1. Gezen F, Kahraman S, Canakci Z, Bedük A. Review of 36 cases of spinal cord meningioma. Spine. 2000 Mar 15;25(6):727-31. [Medline]
2. McCormick PC. Surgical management of dumbbell and paraspinal tumors of the thoracic and lumbar spine. Neurosurgery. 1996 Jan;38(1):67-74; discussion 74-5. [Medline]
3. Matsumoto S, Hasuo K, Uchino A, Mizushima A, Furukawa T, Matsuura Y, Fukui M, Masuda K. MRI of intradural-extramedullary spinal neurinomas and meningiomas. Clin Imaging. 1993 Jan-Mar;17(1):46-52. [Medline]
4. Levy WJ Jr, Bay J, Dohn D. Spinal cord meningioma. J Neurosurg. 1982 Dec;57(6):804-12. [Medline]
5. Kaiser MC, Ramos L. MRI of the spine. In: Tumors. New York: Thieme Medical Publishers, Inc., 1990: 67–8.
6. Mirimanoff RO, Dosoretz DE, Linggood RM, Ojemann RG, Martuza RL. Meningioma: analysis of recurrence and progression following neurosurgical resection. J Neurosurg. 1985 Jan;62(1):18-24. [Medline]