A middle aged female presents with prolonged history of back pain followed by slowly progressive weakness of both lower limbs, spasticity and recent onset difficulty in micturation. On neurological examination there is evidence of dorsal myelopathy. MRI scan of spine shows a well-defined mid-dorsal intradural homogenous contrast enhancing mass lesion. The likely diagnosis is:
Answer is D (Spinal meningioma): The clinical picture and MR] findings of an intradural, contrast-enhancing lesion in the dorsal spine are typical of spinal meningiontas. `The typical clinical scenario of intraspinal meningiomas is a middle aged woman with signs and symptoms of cord or nerve root compression. The dorsal (Thoracic) spine is most commonly involved. At MR1 scan, the tumor typically appears as a well-circumscribed lesion iso-intense or slightly hypotense to the spinal cord. On T1 and T2 sequences with homogenous gadolinium (contrast) enhancement' -Learning Musculoskeletal Imaging (Springer) 2010/101 Meningiomas are typically characterized by isointense homogenous contrast enhancement. Epidermoid cyst, Dermoid cysts and Lipomas do not show contrast enhancement. Characteristic Features of Benign Extramedullary Spinal Tumors: Characteristic Meningioma Schwannoma Neurofibroma Age of presentation 5th-7th decade Sth decade 4th decade Spinal level predominance Thoracic (80%) All levels evenly Cervical (66%) Multiplicity Ito 2% Rare unless NF2 associated Common Propoion or primary spinal tumors 25% -33% 3.5% Gender predominance Female (75-80%) None None Associations More commonly psammomatous or transitional histologies NF2, merlin/schwannomin gene on chromosome 22 NF1, neurofibromin gene on chromosome 17 NF1, neurofibromatosis type 1; NF2, neurofibromatosis type 2 Spinal Meningiomas: Review Spinal meningiomas are believed to originate from arachnoid cap cells of neural crest or mesodermal origin (meningiomthelial cells). Spinal meningiomas are primarily intradural tumors, although extradural meningiomas have been repoed in 3-15% of cases. Majority of spinal meningiomas are extramedullary intradural tumors.Q Spinal meningiomas are the second most common spinal intradural tumors after nerve sheath tumors (Schwannomas) Schwannomas are the most common intradural spinal tumors. Spinal meningiomas are rare in children and are primarily believed to be tumors of Adults. Spinal meningiomas can be found at any age but they are most commonly seen in the 5th to 7th decade. The mean age of diagnosis is -50 years. Most spinal meningiomas occur in woman (75-85%) Spinal meningiomas are most commonly seen in middle aged femalese Spinal meningiomas may be seen in the cervical spine, thoracic spine or the lumbar spine, but are most frequently seen in the thoracic spine. Within the spinal axis, meningiomas are most frequently seen in the thoracic/dorsal spine (70-80%) Most meningiomas are slow growing benign tumors, however higher grade tumors with more aggressive behaviour compose as many as 10% of all meningiomas. The most common and initial symptom of intraspinal meningiomas is pain'. This is followed by variable degree of neurological deterioration, causing defecits depending on tumor location. Impairment of Autonomic pathways are generally uncommon but bowel or bladder involvement can occur as late findings with meningiomas MRI is the investigation of choice for diagnosis of spinal meningiomas At MRI the tumor typically appears as a well-circumscribed lesion iso-intense or slightly hypo-intense to the spinal cord on T I and T2 weighted images. MRI typically shows intense and near homogenous enhancement after contrast (homogenous gadolinium enhancement) The 'dural tail sign ' consisting of dural enhancement adjacent to dural attachment may he seen in spinal meningiomas but this is not specific to meningiomas and may be seen in other conditions like metastasis, sarcoidosis, lymphomas etc.
Intradural Lipoma
Dermoid cyst
Epidermoid cyst
Spinal meningioma