====== Spinal Ependymoma Magnetic Resonance Imaging ====== {{rss>https://pubmed.ncbi.nlm.nih.gov/rss/search/1RMSezfb-YLsPH6BirUGJPYwKJjh174DuOh28b3811kdjjoc3b/?limit=15&utm_campaign=pubmed-2&fc=20230110065350}} ---- ---- [[MRI]] is the modality of choice for evaluating suspected [[spinal cord tumor]]s. Features include: widened [[spinal cord]] (as [[ependymoma]]s arise from ependymal cells lining the central canal, they tend to occupy the central portion of the [[spinal cord]] and cause symmetric cord expansion) although unencapsulated, they are well-circumscribed tumoral [[cyst]]s are present in 22%. Non-tumoral cysts are present in 62%. [[Syringohydromyelia]] occurs in 9-50% of cases In contrast to [[intracranial ependymoma]]s, [[calcification]] is uncommon average length of four vertebral body segments Typical signal characteristics: {{::spinalcordependymomamrit1.jpg|}} [[T1]]: most are [[isointense]] to [[hypointense]]; mixed signal lesions are seen if cyst formation, tumour necrosis or haemorrhage has occurred. {{:undefined:spinalcordependymomamrit2.jpg|}} T2: hyperintense peritumoural oedema is seen in 60% of cases associated haemorrhage leads to the “cap sign” (a hypointense haemosiderin rim on T2 weighed images) in 20-33% of cases. The cap sign is suggestive of but not pathognomonic for ependymoma as it may also be seen in [[Spinal cord hemangioblastoma]]s and [[paraganglioma]]s. T1 C+ (Gd): virtually all enhance strongly, somewhat inhomogeneously. {{::spinalcordependymomamri.jpg|}} [[Hypointensity]] at the tumor margin was found to be a relatively firm pseudocapsule, and [[Hypointensity]] within the tumor corresponded to intratumoral hematoma. All of the tumors with [[Hypointensity]] were ependymomas at histologic examination. When MR imaging shows an intramedullary tumor with [[Hypointensity]] at the tumor margin, it is suggestive, but not pathognomonic, of an ependymoma ((Nemoto Y, Inoue Y, Tashiro T, Mochizuki K, Oda J, Kogame S, Katsuyama J, Hakuba A, Onoyama Y. Intramedullary spinal cord tumors: significance of associated hemorrhage at MR imaging. Radiology. 1992 Mar;182(3):793-6. PubMed PMID: 1535896. )). ---- {{::spinalcordtumormri.jpg?600|}} [[Intramedullary]] expansive lesion compatible with [[neoplasia]] of about 13.4 cm in length, originating at the level of [[C4]]-[[C5]] up to D4-D5, presenting cranial and caudal [[cyst]]ic areas and a solid component at the [[Th1]]-[[Th3]] level presenting [[enhancement]] of about 43 mm in diameter length and another solid component at the C5 level of 11 mm in length. At the caudal level, the [[lesion]] presents a [[hemosiderin]] cap or bleeding, slightly [[hyperintense]] on [[T1]] and [[hypointense]] on [[T2]]. Given its location and radiological appearance, it suggests that it is an [[ependymoma.]] Extensive [[spinal cord edema]] proximal and distal to the lesion is associated, extending from the [[tectum]] to [[T8]]. Leptomeningeal enhancement along the entire spinal cord and some roots of the [[cauda equina]] (more evident in right L5) compatible with tumor extension along the [[neuraxis]]. Vertebral lesion affecting the pedicle and the left [[lamina]] of [[Th8]] that appears slightly hypointense on T1 and hyperintense on STIR and T2, with contrast enhancement. The lesion appears to present some hypointense septum on T2, it could present some medulla foci inside it, so it probably corresponds to an atypical [[hemangioma]]. ---- On MRI majority of 12(63.2%) of the cord [[ependymoma]]s and a majority of 5(62.5%) [[astrocytoma]]s were in the cervical region. While considering axial location ependymomas are mostly 17(89.5%) central and astrocytomas 5(62.5%) are eccentric in location. It was observed that out of 19 cases of ependymoma more than half 10(52.6%) had elongated shapes, and 12(63.1%) had well-defined margins. Associated [[syringohydromyelia]] was present in 16(84.2%) cases. On T1WI 11(57.9%) and 8(42.1%) cases were iso and hypo respectively. On T2WI 14(73.7%) cases were hyper-intense. After Gd-DTPA in most cases, 13(68.4%) cases showed diffuse enhancement. Noticeable and sizeable solid components were observed among 13(68.4%) of the cases. Hemorrhage with a cap sign was found in more than one-third of 7(36.8%) cases. Out of 8 cases of astrocytomas 4(50.0%) had lobulated shape, ill-defined margin 5(62.5%). T1WI: Iso 5(62.5%), hypo 3(37.5%), T2WI: hyper 5(62.5%), After Gd-DTPA: focal and heterogenous enhancement 3(37.5%) and rim enhancement 4(50.0%). Component: mixed 4(50.0%), cystic 3(37.5%) and solid 1(12.5%). Hemorrhage without cap sign 2(25.0%), associated syringohydromyelia 1(12.5%). In the case of evaluation of intramedullary ependymoma sensitivity of MRI in the present series is 94.44%, specificity 80.0%, Positive predictive value (PPV) 89.5%, Negative predictive value (NPV) 88.9% and accuracy 89.28%. In the case of MRI evaluation of intramedullary astrocytoma sensitivity of MRI in the present study is 85.71%, specificity 90.47%, PPV 75%, NPV 95%, and accuracy 89.2%. Thus present study shows MRI is a sensitive and effective noninvasive imaging modality in diagnosing common [[intramedullary spinal cord tumor]]s ((Sultana N, Jabeen S, Rima S, Nag UK, Sarkar SK. Magnetic Resonance Imaging Evaluation of Common Spinal Intramedullary Tumours: [[Ependymoma]] and [[Astrocytoma]]. Mymensingh Med J. 2023 Jul;32(3):749-756. PMID: 37391969.))