Meningioma¶

Definition¶

Meningioma is a benign tumor arising from arachnoid cap cells of the meninges. Spinal meningiomas are the second most common intradural extramedullary tumor after schwannoma. They are strongly associated with middle-aged to older women (female-to-male ratio approximately 4:1) and most commonly occur in the thoracic spine.

Imaging Findings¶

MRI¶

Location — Intradural extramedullary, most commonly in the thoracic spine (80%). Typically lateral or posterolateral, arising from the dura.
T1-weighted — Isointense to the spinal cord
T2-weighted — Isointense to slightly hyperintense to the cord (much less bright than schwannomas)
Enhancement — Intense, homogeneous enhancement
Dural tail sign — Linear enhancement of the dura extending from the tumor margins, present in approximately 60% of cases. While not pathognomonic (can be seen with other dural-based lesions), it is a strong clue to the diagnosis.
Broad dural base — The tumor has a wide attachment to the dura, unlike nerve sheath tumors which are more spherical/eccentric
CSF cap — CSF visible between the tumor and the cord
Calcification — May appear as signal void on all sequences

CT¶

Iso- to hyperdense mass (may show calcification)
Homogeneous enhancement
No foraminal widening (unlike schwannoma)
CT myelography shows intradural filling defect

Thoracic spinal meningioma MRI — Thoracic spinal meningioma at T7–T8. Sagittal and axial T1 post-contrast MRI showing a homogeneously enhancing intradural extramedullary mass with ventral displacement and compression of the spinal cord. (Source: PMC11011121, Medicina, 2024. CC BY 4.0)

Cervical spinal meningioma MRI — Cervical spinal meningioma at C4–C6. Sagittal and axial T1 post-contrast and T2-weighted MRI showing a ventrolateral enhancing mass with extension into the neural foramen. (Source: PMC11011121, Medicina, 2024. CC BY 4.0)

Meningioma with dural tail sign — Spinal meningioma at T12. T2-weighted and post-contrast T1-weighted MRI showing the dural tail sign — linear enhancement of the dura extending from the tumor margins (arrows). (Source: Yoo et al., PLoS ONE, 2020. CC BY 4.0)

Distinguishing from Schwannoma¶

Feature	Meningioma	Schwannoma
Location	Thoracic (80%)	Lumbar/cervical more common
Dural attachment	Broad-based	Eccentric, nerve root based
Dural tail	Present (~60%)	Absent
T2 signal	Isointense to cord	Hyperintense
Cystic change	Rare	Common
Foraminal extension	Rare	Common (dumbbell)
Demographics	Women 40–70	No sex predilection

Clinical Pearl

A well-defined, homogeneously enhancing intradural extramedullary mass in the thoracic spine of a middle-aged woman with a broad dural base and dural tail sign is virtually diagnostic of meningioma. This clinical-imaging combination is highly specific.

Management¶

Surgical excision is curative in most cases
Recurrence rate depends on completeness of resection (Simpson grade)
Observation may be appropriate for small, asymptomatic lesions in elderly patients

Key Points¶

Second most common intradural extramedullary tumor
Strong predilection for thoracic spine in middle-aged women
Homogeneous enhancement with dural tail and broad dural base
T2 signal is isointense to cord (unlike T2-bright schwannomas)
Surgical excision is usually curative

References¶

Dang DD, Mugge LA, Awan OK, Gong AD, Fanous AA. Spinal meningiomas: a comprehensive review and update on advancements in molecular characterization, diagnostics, surgical approach and technology, and alternative therapies. Cancers (Basel). 2024;16(7):1426. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC11011121/
Koeller KK, Shih RY. Intradural extramedullary spinal neoplasms: radiologic-pathologic correlation. RadioGraphics. 2019;39(2):468-90. Available from: https://pubmed.ncbi.nlm.nih.gov/30844353/
Zhang LH, Yuan HS. Imaging appearances and pathologic characteristics of spinal epidural meningioma. AJNR Am J Neuroradiol. 2018;39(1):199-204. Available from: https://pubmed.ncbi.nlm.nih.gov/29051204/
Alorainy IA. Dural tail sign in spinal meningiomas. Eur J Radiol. 2006;60(3):387-91. Available from: https://pubmed.ncbi.nlm.nih.gov/16876365/
El-Hajj VG, Pettersson-Segerlind J, Fletcher-Sandersjöö A, Edström E, Elmi-Terander A. Current knowledge on spinal meningiomas epidemiology, tumor characteristics and non-surgical treatment options: a systematic review and pooled analysis (Part 1). Cancers (Basel). 2022;14(24):6251. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC9776907/
Alruwaili AA, De Jesus O. Meningioma. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2024. Available from: https://www.ncbi.nlm.nih.gov/books/NBK560538/
Spinal meningioma. Radiopaedia.org. Available from: https://radiopaedia.org/articles/spinal-meningioma