From the Guidelines
MRI findings in meningioma typically include a well-circumscribed, extra-axial mass that is isointense to slightly hypointense on T1-weighted images and isointense to slightly hyperintense on T2-weighted images. These tumors show avid, homogeneous enhancement after gadolinium contrast administration due to their rich vascularity. A characteristic "dural tail" sign, representing thickened enhancing dura extending from the tumor, is present in about 60-72% of cases. Meningiomas often cause adjacent bone changes including hyperostosis or erosion. They may demonstrate calcifications, and can show restricted diffusion on diffusion-weighted imaging. Peritumoral edema is variable but common in larger tumors. On MR spectroscopy, meningiomas typically show elevated choline, decreased N-acetylaspartate, and a characteristic alanine peak at 1.5 ppm. These imaging features help differentiate meningiomas from other intracranial masses such as schwannomas, metastases, or high-grade gliomas, though definitive diagnosis requires histopathological confirmation, as noted in recent guidelines for diagnostics and therapy of meningiomas 1. Key features of meningioma on MRI include:
- Well-circumscribed, extra-axial mass
- Isointense to slightly hypointense on T1-weighted images
- Isointense to slightly hyperintense on T2-weighted images
- Avid, homogeneous enhancement after gadolinium contrast administration
- Characteristic "dural tail" sign in about 60-72% of cases
- Adjacent bone changes including hyperostosis or erosion
- Restricted diffusion on diffusion-weighted imaging
- Peritumoral edema in larger tumors
- Elevated choline, decreased N-acetylaspartate, and a characteristic alanine peak at 1.5 ppm on MR spectroscopy.
From the Research
MRI Findings in Meningioma
There are no specific MRI findings mentioned in the provided studies. However, the studies discuss the diagnosis, treatment, and management of meningiomas, which may involve the use of MRI scans.
Diagnosis and Treatment
- Meningiomas are the most common primary intracranial tumor, and their management often entails serial monitoring or a combination of surgery and/or radiation therapy 2, 3.
- The current WHO grading scale for meningioma is used to classify these tumors, and genetic and epigenetic features may supplement or replace histopathologic features for improved identification of aggressive lesions 2.
- Surgery and radiotherapy are the primary therapeutic modalities for meningiomas, and radiation therapy can be used as a primary treatment for small meningiomas or for treatment of recurrences after surgery 3, 4.
Molecular Characteristics and Future Directions
- Advances in genomics and molecular characteristics of meningiomas have uncovered potential uses for more accurate grading and prediction of prognosis and recurrence 5.
- Specific biologic targets are being trialed for possible management of meningiomas that are not responsive to standard surgery and radiotherapy treatment 5, 6.
- Systemic therapies, such as everolimus-octreotide combination, bevacizumab, sunitinib, and peptide receptor radionuclide therapy, may be considered for patients with recurrent meningioma not amenable to further surgery or radiotherapy 6.