A 45 yr old female complains of progressive lower limb weakness, spasticity, urinary hesitancy. MRI shows intradural enhancing mass lesion. MOST likely diagnosis is:

Meningioma are now the most common primary brain tumor. On an MRI it appears as a paially calcified densely enhancing extra axial tumor arising from the dura. Occasionally it has a dural tail, consisting of thickened, enhanced dura extending like a tail from the mass. Meningiomas are typically located over the cerebral convexities, especially adjacent to the sagittal sinus. It can also occur in the skull base and along the dorsum of the spinal cord. They are more common in women and in patients with neurofibromatosis type 2. They also occur more commonly in patients with a past history of cranial irradiation. Most of them are found incidentally, but it can also present with headache, seizures or focal neurologic deficits. Ref: Harrison's Principles of Internal Medicine, 18e chapter 379.