E4872. Diagnostic Imaging Features of Intramedullary Spinal Neoplasms
  1. Ali Hannachi; National Neurology Institute
  2. Insaf Dkhil; National Neurology Institute
  3. Soumaya Jelassi; National Neurology Institute
  4. Sonia Nagi; National Neurology Institute
Intramedullary spinal masses represent a diverse spectrum of pathological conditions that can profoundly impact neurological function. The study of these masses through radiologic imaging techniques plays a pivotal role in their accurate diagnosis, subsequent management, and overall patient care. Intramedullary spinal masses encompass a wide array of entities, ranging from benign to malignant neoplasms and nonneoplastic conditions. The accurate identification and differentiation of these masses are paramount due to the intricate anatomy of the spinal cord and the potential for significant neurological deficits that may arise from their presence.

Educational Goals / Teaching Points
- Identify the characteristic imaging patterns of intramedullary neoplasms and learn to differentiate these neoplasms from other spinal cord lesions. - Recognize the radiological manifestations of intramedullary neoplasms and understand their correlation with tumor types and locations. - Acquire knowledge about the various histological subtypes of intramedullary neoplasms, their distinct features, and their associated clinical behaviors.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Ependymoma and astrocytoma are the most common intramedullary spinal tumors, accounting for about 70% of all intramedullary spinal neoplasms. Ependymoma is the most common intramedullary spinal tumor in adults. It presents as an enhancing mass with well-circumscribed margins which expands outward from the ependymal lining of the central canal and is more centered than eccentric in location. It is hypointense to isointense in T1 and isointense to hyperintense in T2. It is usually heterogeneous, with cystic or hemorrhagic components including polar cysts and the hemosiderin “cap” sign. Astrocytoma is the most common primary intramedullary spinal neoplasm in childhood. At imaging, it manifests as an expansile lesion, eccentric to the central canal, with a range of possible enhancement patterns, ranging from nonenhancing to homogeneously or heterogeneously enhancing. The third most common consideration for a spinal cord neoplasm is hemangioblastoma. It manifests as a hypervascular tumor centered at the pial surface of the spinal cord. Other spinal cord tumors include pilocytic astrocytoma, ganglioglioma, oligodendroglioma, and myxopapillary ependymoma. It is important to remember that not all expansile lesions are neoplastic. There is inflammatory myelitis, congenital or developmental lesions, arteriovenous malformations, cavernomas, and others.

Accurate diagnosis of intramedullary neoplasms relies on a thorough understanding of their imaging characteristics. MRI, with its diverse sequences, is essential for differentiating various types of tumors and guiding treatment decisions.