Intradural/Extramedullary Lesion, T2 Hyper, T1 Iso

Jeffrey S. Ross, MD

DIFFERENTIAL DIAGNOSIS

Common

Less Common

Rare but Important

ESSENTIAL INFORMATION

Helpful Clues for Common Diagnoses

Schwannoma
- Well-circumscribed, dumbbell-shaped, enhancing spinal mass
- 30% of primary spine tumors
- 75% T2 hyperintense
- Solitary unless part of inherited tumor syndrome, such as NF2
- Scan entire spine in asymptomatic patients with suspected neurofibromatosis type 2
Neurofibroma
- Bulky multilevel spinal nerve root tumors in patient with NF1
- Rapid growth of NF suggestive of malignant transformation
- Target sign suggestive of neurofibroma => peripheral high signal, central lower signal
Epidermoid
- Nonenhancing intradural mass similar to CSF signal on T2/T1 images
Ependymoma
- Myxopapillary type within caudal sac may show near iso T1 signal, T2 hyperintensity
- Large fraction (20-30%) may show little enhancement
CSF Disseminated Metastases
- Look for “dirty” CSF appearance on T1, with indistinct cauda and conus
- Diffuse or nodular enhancement along cauda equina

Helpful Clues for Rare Diagnoses

Capillary Hemangioma
- Benign tumor of endothelial cell origin
- T2 hyperintense enhancing well-defined intradural mass
- May be indistinguishable from meningioma or schwannoma
Neurenteric Cyst
- Intraspinal cyst and vertebral abnormalities
- Osseous canal enlargement, widening of interpedicular distance
- Iso- → hyperintense T1 reflecting protein/mucin content