 Hello! Myself Dr. Shubham Arya, the topic of my presentation is MRI evaluation of inter-dural extramedulary spinal tumor. The spinal cord is the part of the central nervous system that is found within the spinal canal of the vertebral column. The cord extends from the cortical medullary junction and the foremen magnum of the ispel down to the tip of onus medullaris. The spinal cord is covered by three layers of meninges, from outer to inner. They are the dura matter, the anachnoid matter and the pyrometer. In this image we can see, this is the spinal cord and this outer one dark blue is the dura matter. The orange color represents the lesion. In this case we can see this orange color lesion is located within the spinal cord. So it is intramedulary. In this image we can see the orange color lesion. It is located outside the spinal cord and it is, it is compressing the cord. But it is within the dura matter, so it is intradural extramedulary lesion. In this image, we can see the lesion life outside the dura mater, so it is extradural lesion. On the basis of the location of the spinal tumor, they can be divided into intradural or extradural. Amongst extradural metastases are the most common ones. In intradural, again it can be divided into intramedulary and extramedulary. Intramedulary are the ones those are located within the spinal cord and extramedulary are the ones which are located outside the spinal cord. Overall, intradural extramedulary spinal tumors are the most common ones. Intradural extramedulary tumors are located inside the dura but outside the spinal cord. They might develop from nerve roots or from inside surface of the dura mater. Many tumors and the noxious tumors make up the majority of the intradural extramedulary tumors. All spinal levels may be involved. All lesions can be single or multiple, however, paraganglioma is often single. Lesion causes widening of the CSF spaces and they cause compression of the spinal cord. Some serious intradural extramedulary lesions, schwannoma and meningioma are the most common ones. Other being neurofibroma, leptomeningal metastasis, myxopepillary effendymoma, paraganglioma, hematoma dermoid and epidermoid. Patient usually present with the signs and symptoms of spinal cord or nerve root compression. And the common presentation include weakness, localized back pain, reticular pain, sensory deficit and gait at XR. The diagnostics include MRI including contrast enhancement, CT for bone window with reconstruction and possible CT myelogram. However, the modality of choice is contrast enhanced MRI and the preferred treatment in most of these cases is microsurgical radical resection. Now, our first case is a 38 year female who presented with a complaint of neck pain since one year, which was radiating to bilateral upper limb and associated with tingling and numbness. In these images, we can see a well defined intradural extramedulary lesion with a broad base towards dura mater with which shows a dural tail sign. This is a T1 sagittal images in which the lesion appears iso to hyperintense to the cord. In this T2 sagittal and T2 exel image, we can see the lesion appears iso to hyperintense to the cord with T2 peripheral hyper, a hypo intense rib. Also blooming was noted on the medics sequence which denotes calcification. These are the post contrast images, sagittal section, coronal section and axial section which shows intense homogenous enhancement of the lesion. This lesion is spanned from the lower border of T4 vertebra to the lower border of T5 vertebra and no evidence of extension into the bilateral neural foramina was noted. So on the basis of the imaging finding, the diagnosis of spinal meningioma was made. Now, our next case is a 15 year male who presented with a complaint of neck pain since one year radiating to right upper limb associated with numbness. However, no history of fever was present on anti-examination, right palatal palsy and right mucal core palsy was present. In these images, we can see intradural extramedulary mass with broad base towards dura. However, no dual tail sign is noted. The lesion is located one at C6 T1 vertebra level and other one is at C1 C2 vertebra level. This is T1 sagittal section where the lesion appears iso to hypo intense to spinal cord. In T2 sagittal image, we can see the lesion appear heterogeneously hyper intense to spinal cord and this in diffusion weighted we can see the restriction. In the post contrast images, this is coronal section and this sagittal section, we can see the lesion shows homogenous contrast enhancement. Also the CEMRI brain of the patient was done and we found that there was a solid mass lesion with intracanalcular extension in bilateral cerebellum fontine angle which suggests bilateral cere...CPA schwannoma. So along with the various spinal schwannoma and bilateral CPA schwannoma, the diagnosis of neurofibromatosis type 2 was made. Our next case is a 24 year old male who presented with the complaints of pain in the lower back with radiation to right lower limb since 1.5 years which was with progressive weakness, numbness and tingling sensation of bilateral lower limb. Occasional bladder incontinence was present, there was no history of bowel involvement on examination vital to a stable motor and sensory examination was normal, rest of the neurological and other systemic examination was within normal limit. Patient is a post-operative follow-up case of mesopapillary appendymoma. In these images, we can see a well-defined intradural extramedural lesion involving the conus medullaris and phylum terminus and extending from the lower border of L2 to the lower border of L3 vertebral level. The lesion appears hyper intense on T1 image and this on T2 sagittal image, we can see the lesion appears heterogeneously iso to hyper intense and it shows mild diffusion restriction. On post contrast images sagittal section, coronal section and the axial section, we can see the lesion shows homogeneous contrast enhancement. However, no hemorrhage or extension of the lesion into the nodar polamina was noted. As this is a known case of mesopapillary appendymoma and it is a post-operative case, so the final diagnosis was made as recurrent or residual mesopapillary appendymoma. Our next case is a 9-year-old girl who is a post-op case of medulla blastoma for which she received radiotherapy also. Now she presented with a complaint of difficulty in walking. In these images, we can see diffused lefto-menangeal thickening and enhancement with multiple nodular enhancing lesions in the surface of the cervical, dorsal and lumbar spinal cord from C3 to L1 vertebral level. In T1 sagittal image, lesion appears iso to hyper intense, so it is very difficult to see the lesion in just T1 images. In T2 section, sagittal section, we can see the lesion appears hyper intense and on diffusion restriction, diffusion images, we can see the lesion shows diffusion restriction. This is a post contrast image where the lesion shows nodular enhancement. So the diagnosis of lefto-menangeal drop metastasis was made. Now to start with the discussion, first is meningioma. Meningiomas are often located posterior-laterally in the thoracic region and anteriorly in the cervical region. Mostly, they are solitary lesion. Multiple meningiomas are often associated with NF2. On imaging, plane films, meningiomas, plane films appears normal and really bone erosion or calcification may be seen. On non-contrast CT, we will see iso dense or moderately hyper dense mass lesion. Hyperostosis may be seen, but it is not as common as in the intra-cranial meningioma. Calcification may be present. On MRI, the meningioma appears as well-subcombed broad-based neural attachment, which is a neural tail sign. On T1, they appear iso intense to slightly hypo intense and may have heterogeneous texture. On T2, they appear iso intense to slightly hyper intense and on contrast, they show moderate homogenous enhancement. Occasionally densely-calcified meningiomas are hypo intense on T1 and T2 and show only minimal contrast enhancement. Spinal meningiomas are typically slow-growing and surgery is the treatment of choice for them. Less than 10% experience recurrence. The differential diagnosis for it are the nerve-sheet tumors that is the spinal schwannoma and the spinal neurofibroma. Next, we have other nerve-sheet tumors, which are schwannomas and neurofibroma. Schwannomas are more common while the neurofibroma is only occurring in association with NF1. Meningan degeneration of the neurofibroma may occur in patients with NF1, but schwannoma rarely undergo meningioma transformation. Approximately 50% of the nerve-sheet tumors are intradural, extradural. That is, they are dumber-shaped and 50% are purely extradural. Both masses are slow-growing and cause bone remodelling and both show low T1 and high T2 signals. Meningic spaces and hemorrhage are more commonly schwannomas than in neurofibroma. Both may show homogenous or inhomogeneous contrast enhancement, but neurofibroma, they typically have a ring shape or the target type of enhancement, in which the central portion of the mass remains slightly hypointal after contrast administration. Schwannomas are actually slow-growing lesions but can be debilitating. They almost never undergo meningioma transformation and surgery is the treatment of choice. Most total dissection is usually curative for the patient with sporadic tumors. For patients with NF2, there is high incidence of new tumor formation. Now moving to next, which is myxopapillary ependymoma. Most frequent type of ependymoma, which are found at the phonus medullaries, coda equinin phylum terminal level, are the myxopapillary ependymoma. They are thought to arise from the ependymal glial of the phylum terminal and they manifest with a low back pain, sacral pain or the weakness or sphincter dysfunction. So imaging the appears as globulated sausage shaped mass that are often encapsulated. On T1, they are usually iso intense, which is a finding that reflects musin content on the hemorrhage of the lesion. On T2, they overall appear hyper intense. Low intensity may be due to the hemorrhage. Calcification can also lead to regions of low signal and they always show contrast enhancement. Typically, homogenous, however, can be variable due to the hemorrhage. They are slow growing WHO grade 2 tumors. Occasionally CSF dissemination and multiple lesions are seen. Some sacred lesions are locally aggressive and metastasized to live note, lungs and bones. Aggressive behavior of the lesion is more commonly seen in case of children. They can often be excised completely with accident prognosis with a 5 year survival rate of 98%. If the tumor has extended to the conus medullaries, the section is often incomplete with a greater risk of local recurrence and there is a greater risk of neurologic deficit. This is what we saw in our case of myxopepillary appendymoma. And for differential diagnosis, if the lesion is small, then we can differential diagnosis could be schwannoma and the paraganglioma. If the lesion is large and it is causing destruction of the sacrum, then the lesion could be anusual bone cyst, caudoma or the giant cell tumor. Next, we have the leptomanageal metastasis. They are frequently seen in the setting of the solid tumor. The most common ones are melanoma, small cell lung cancer and breast cancer and in hematologic malignancies. In children, the most common interdural extra medullary neoplasma is the drop metastasis from the primary brain tumor. And among with the most common one is medulloblastoma as we saw in our case. In adults, the non-CNS tumors are the most commonly encountered ones. However, in case of the CMS, the most common drop metastasis are from the glioblastoma. In MRI, in non-contrast MRI, it is very difficult to pick a lesion, so that may appear normal. Because whenever suspected, contrast should be administered and typical characteristics findings in the MRI are on T1, it will appear thickened nerve root with nodular lesions that are iso intense with the spinal cord. On T2, we will see the caud edema may be present with more extensive disease, especially if there is intra medullary component. On contrast, there will be enhancing tumor nodules on the spinal cord, nerve root or the caudaic pointa and the sugar coating of the spinal cord and the nerve root is seen. The treatment of prognosis of the leptomanageal metastasis is actually poor and it depends on the primary tumor. No surgical cure is possible and the treatment results around the systemic chemotherapy and radiotherapy to the nerve axis. For differential diagnosis, if there is diffused disease, then differential could be meningioreticalitis, electroniditis, and gullian bar syndrome. If there is a nodular disease, it could be spinal meningioma, spinal sonoma, neurofibroma or pyrlipoma. So, the summing in conclusion of my presentation, contrast enhanced MRI is the modality of choice to fully characterize these masses and the relationship of the masses to the cord, the dura, the nerve roots. In addition, MRI can help in identifying secondary lesions and the large feeding and the draining results if they are present. Various distinguishing features of the lesions are in meningioma, we will see the dural involvement with the dural tail sign, homogenous contrast enhancement and the ginkgo leaf sign. Ginkgo leaf sign is actually used to distinguish between the spinal tumor, that is spinal meningioma from a neurogenic tumor, that is spinal schwannoma. It is seen on the axial post contrast even imaging in which the leaf represents the distorted spinal cord pushed to one side of the thical sag by the meningioma and the stem is seen as non-enhancing streak probably representing the stress denticulate ligament. In the nerve sheet tumor, we see the nerve root involvement, extra dural neurofibroma extension with dumbbell appearance of the lesion. The schwannomas are actually rounded or oval in shape, they show markedly to hyperintensity and heterogeneous cystic changes when they are large and they displace as a nerve root whereas neurofibroma are actually fusiform or flexiform in shape, they show markedly to hyperintensity and they encase the nerve root. Leptomenangeal metastasis, in this we will see the spinal cord margins for the nerve root involvement especially the cordi-coiner with multi-coccal nodular enhancement. Mixo-peplary appendiomoma usually involves the cordi-coiner reason and the lesion appears, shows its shape in morphology. The neuroendocrine tumor that is paraganglioma, cordi-coiner region is involved with prominent flow void is seen, also the capstein is seen, capstein is actually the T2-hypointensity above or below the lesion which is due to the previous hemorrhage and that is due to the hemocidrin deposit. So, the preferred treatment in all these cases mostly is the microsurgical-radical