Neoplasms of the spinal cord and filum terminale: radiologic-pathologic correlation

Magnetic Resonance Imaging Features of Intramedullary Schwannomas

OBJECTIVE

To identify the magnetic resonance imaging features of intramedullary spinal schwannomas.

METHODS

Clinical and magnetic resonance imaging findings of 8 patients with pathologically confirmed intramedullary schwannomas were reviewed.

RESULTS

There were 6 male and 2 female patients (mean age, 49 years). Tumors were located in the cervical cord (2), the thoracic cord (5), and the cervicothoracic cord (1). Most were in the dorsolateral spinal cord and limited to one side. Expansion of the cord was observed. The majority were hypointense on T1-weighted images and hypo-hyperintense on T2-weighted images. Peritumoral edema was easily found. Gadolinium enhancement was obviously. No recurrence was seen during the follow-up period.

CONCLUSIONS

A tumor located in the dorsolateral spinal cord, causing expansion of the cord, with hypointense areas on T2-weighted and obviously enhancement, should arise suspicion of an intramedullary schwannoma.

Spinal diffusion tensor tractography for differentiation of intramedullary tumor-suspected lesions

BACKGROUND AND PURPOSE

Primary MRI diagnosis of spinal intramedullary tumor-suspected lesions can be challenging and often requires spinal biopsy or resection with a substantial risk of neurological deficits. We evaluated whether Diffusion Tensor Imaging (DTI) tractography can facilitate the differential diagnosis.

MATERIALS AND METHODS

Twenty-five consecutive patients with an intramedullary tumor-suspected lesion considered for spinal surgery were studied with a Diffusion-weighted multi-shot read out segmented EPI sequence (RESOLVE). White matter tracts ("streamlines") were calculated using the FACT algorithm and visually co-registered to a T2-weighted 3D sequence. The fused images were assessed concerning spinal streamline appearance as normal, displaced or terminated. Definite diagnosis was verified by histological analysis or further clinical work-up.

RESULTS

All patients with normal appearing streamlines (n=6) showed an acute inflammatory demyelinating pathology in the further clinical work-up. In 10 patients streamline displacing lesions were found from which 5 patients underwent a surgical treatment with histologically confirmed low-grade tumors like ependymomas and pilocytic astrocytomas. In nine patients streamlines were terminated, from which 6 patients received a histology proven diagnoses with a more heterogenous spectrum (3 cases of high grade tumor, 1 case of low grade tumor with intralesional hemorrhage and 2 cases with gliosis but no tumor cells).

CONCLUSION

Using multi-shot DTI spinal tractography acute inflammatory lesions can be differentiated from other tumorous intramedullary lesions. The entity diagnosis of spinal tumors seems to be more challenging, primarily due to the variety of factors like invasivity, expansion or intralesional hemorrhage.

Primary spinal tumors in childhood: A single institution 15 year experience

BACKGROUND

Pediatric primary spinal tumors (PST) are fairly uncommon, with little available data regarding incidence and outcomes.

MATERIALS AND METHODS

We conducted a retrospective review of the 22 consecutive patients less than 18 years old diagnosed with PST between March 1997 and May 2011 and treated at Chang Gung Children Hospital. All patients had undergone magnetic resonance imaging (MRI) for pre-operative evaluation and operations for PST. The extent of tumor removal was assessed by surgical report by the neurosurgeon or by post-operative MRI if available.

RESULTS

Ten of them had intramedullary tumors and 12 had intradural extramedullary tumors. All patients were treated with surgery to the primary site. A total of 15 patients underwent gross total tumor resection and seven patients received post-operative radiotherapy. Five patients received adjuvant chemotherapy for their primary tumor. Fourteen patients (64%) survived from study entry without tumor progression.

CONCLUSIONS

PST encompassed a diverse group of pathologic entities that differ markedly based on the location and age of the children. Total resection of pediatric PST in children could be performed with acceptable risk and satisfactory long-term results.

Differentiation of recurrent spinal ependymoma from postradiation treatment necrosis through multiparametric PET-MR and perfusion MRI

A 67-year-old male presented with papilledema and back pain localized to the T10 level. Initial workup revealed multifocal spinal ependymoma which was resected and treated with external beam radiotherapy. Nine years after treatment, the patient had a relapse of back pain, and MRI was inconclusive in distinguishing posttreatment radiation necrosis from recurrent tumor. We present the first described report with the utilization of multiparametric positron emission tomography-magnetic resonance imaging and perfusion MRI to distinguish recurrent spinal ependymoma from radiation necrosis.

Primary Neurocytoma in the Spinal Cord

Central neurocytoma is defined as an intraventricular benign brain tumor. Extra-ventricular location of central neurocytoma is rare: only nine cases of spinal neurocytoma had been reported in the English literature. We hereby present a case of atypical neurocytoma involving unusual long segments (8-segment) of cervico-thoracic spinal cord in a 29-year-old woman with emphasis on pre- and post-surgical neuroimaging, pathological correlation, and review the pertinent literature.

A case of an anaplastic meningioma metastasizing to the mediastinal lymph nodes

CONTEXT

Grade II and III (World Health Organization classification) meningiomas rarely develop in the spinal cord. However, we experienced a case with an anaplastic meningioma that developed in the spinal cord at the cervicothoracic junction and metastasized to the mediastinal lymph nodes. No such cases have previously been reported.

FINDINGS

The patient was a 68-year-old man who developed back pain that did not affect his daily living. He developed left lower limb paralysis, and was admitted after magnetic resonance imaging (MRI) revealed an intramedullary tumor at the level of cervical vertebra 7 and thoracic vertebra 1. Positron emission tomography revealed tracer uptake in the intramedullary tumor and the mediastinal lymph nodes, suggesting a metastatic spinal cord tumor or malignant lymphoma. A lymph node biopsy was then performed. Although the tumor was highly malignant, its primary site was not identified. Detailed examinations by several other departments revealed no abnormalities. On hospital day 30, his left lower limb paralysis deteriorated, and MRI revealed that the tumor had grown. Thus, laminaplasty, laminectomy, and tumor resection were performed. The tumor was an anaplastic meningioma that resembled mediastinal lymph node tissue, and other tumor lesions were not found. These findings suggested that an anaplastic meningioma had metastasized to the mediastinal lymph nodes. The patient did not respond to radiotherapy, and he was transferred to another hospital.

CONCLUSION

In cases of intramedullary spinal tumors with metastasis without other potential primary tumor lesions, early diagnosis and treatment should be performed while considering anaplastic meningioma.

Spinal cord ependymoma: a review of the literature and case series of ten patients

Spinal cord ependymoma (SCE) is a rare tumor that is most commonly low-grade. Complete surgical resection has been established as first-line treatment and can be curative. However, SCEs tend to recur when complete tumor resection is not possible. Evidence supporting the use of adjuvant radiation and chemotherapy is not definitive. We review the most recent literature on SCE covering a comprehensive range of topics spanning the biology, presentation, clinical management, and outcomes. In addition, we present a case series of ten SCE patients with the goal of contributing to existing knowledge of this rare disease.

Spinal myxopapillary ependymoma in an adult male presenting with recurrent acute low back pain: a case report

Background

Spinal intramedullary ependymomas are very rare and occur more commonly in the cervical and upper thoracic regions. These neoplasms tend to manifest in young adulthood, and patients typically present with mild clinical symptoms without objective evidence of neurologic deficits. The mean duration of symptoms is 40 months until the lesion is diagnosed.

Case Presentation

A 48-year-old male police officer was referred to a chiropractic clinic by a general practitioner for the evaluation of recurrent acute low back pain (LBP). Although the first episode of LBP was resolved, the clinical examination during the second episode revealed subtle changes that warranted referral to magnetic resonance imaging (MRI). The MRI revealed a spinal myxopapillary ependymoma.

Conclusion

Because the primary symptoms of spinal intramedullary ependymomas can mimic ordinary LBP presentations, in particular lumbar intervertebral disc herniations, clinicians need to be sensitive to subtle changes in the clinical presentation of LBP patients. Prompt referral to advanced medical imaging such as MRI and early neurosurgical intervention is key to achieve best possible outcomes for patients with spinal intramedullary ependymomas.

Primary spinal primitive neuroectodermal tumor on MR imaging

Neoplasms in the region of filum terminale are not uncommon. Myxopapillary ependymoma is the commonest tumor at this location. The differentials reported for this entity are nerve sheath tumor, meningioma, paraganglioma, intradural metastases, lymphoma, other varieties of ependymoma, subependymoma, astrocytoma, ganglioglioma, hemangioblastoma, and primitive neuroectodermal tumor (PNET). PNET may very rarely present as an intradural thoracolumbar mass. We present pre- and post-therapy magnetic resonance imaging (MRI) features of a patient with proven primary spinal primitive neuroectodermal tumor (PSPNET) of peripheral subtype.

Neoplastic cauda equina syndrome: a neuroimaging-based review

Cauda equina syndrome refers to dysfunction of the cauda equina, the collection of ventral and dorsal lumbar, sacral and coccygeal nerve roots that surround the filum terminale. This most commonly occurs as a result of compression by a herniated lumbosacral disc. However, the syndrome may also complicate metastatic cancer or a primary neoplasm within or infiltrating the spinal canal. An accurate and timely diagnosis is critical to avoid irreversible loss of neurological function. The clinician and radiologist must therefore be aware of the many possible causes to guide timely management. Here we review the diverse neoplastic causes affecting the cauda equina nerve roots from a neuroimaging-based perspective. We divide them by location into intramedullary neoplasms at the conus (such as astrocytoma), intradural-extramedullary neoplasms (such as schwannoma and leptomeningeal metastases) and extradural neoplasms (such as spinal metastases from systemic neoplasms). We also discuss the clinical features associated with cauda equina tumours, with special focus on cauda equina syndrome.

Imaging diagnosis and the role of endovascular embolization treatment for vascular intraspinal tumors

Intraspinal tumors comprise a large spectrum of neoplasms, including hemangioblastomas, paragangliomas, and meningiomas. These tumors have several common characteristic imaging features, such as highly vascular mass appearance in angiography, hypointense rim and serpentine flow voids in MRI, and intense enhancement after intravenous contrast administration. Due to their rich vascularity, these tumors represent a special challenge for surgical treatment. More recently, the surgical treatment of intraspinal vascular tumors has benefited from the combination of endovascular techniques used to better delineate these lesions and to promote preoperative reduction of volume and tissue blood flow. Endovascular embolization has been proven to be a safe procedure that facilitates the resection of these tumors; hence, it has been proposed as part of the standard of care in their management.

Specific pattern of gadolinium enhancement in spondylotic myelopathy

OBJECTIVE

To highlight a specific under-recognized radiological feature of spondylotic myelopathy often resulting in misdiagnosis.

METHODS

Patients evaluated between January 1, 1996 and December 31, 2012 who met the following criteria were included: (1) spondylotic myelopathy was suspected, (2) gadolinium enhancement was detected, and (3) spinal surgery was performed.

RESULTS

Fifty-six patients (70% men) whose median age was 53.5 years (range = 24-80) were included. Spinal cord magnetic resonance imaging (cervical in 52; thoracic in 4) revealed longitudinal spindle-shaped T2-signal hyperintensity (100%) and cord enlargement (79%) accompanied by a characteristic pancakelike transverse band of gadolinium enhancement in 41 (73%), typically immediately caudal to the site of maximal spinal stenosis. Forty (71%) patients were initially diagnosed with neoplastic or inflammatory myelopathies, and decompressive surgery was delayed by a median of 11 months (range = 1-64). Spinal cord biopsy in 6 did not reveal any alternative diagnosis. Ninety-five percent were stable or improved. Gadolinium enhancement persisted in 75% at 12 months, raising concern about the accuracy of the initial diagnosis. Twenty patients required a gait aid (36%) at last follow-up (median = 60 months, range = 10-172). The need for a gait aid preoperatively (p = 0.005), but not delay of surgery, predicted the need for gait aid at final follow-up.

INTERPRETATION

Transverse pancakelike gadolinium enhancement associated with and just caudal to the site of maximal stenosis and at the rostrocaudal midpoint of a spindle-shaped T2 hyperintensity suggests that spondylosis is the cause of the myelopathy. Persistent enhancement for months to years following decompressive surgery is common. Recognition is important to prevent inappropriate interventions or delay in consideration of a potentially beneficial decompressive surgery.

Interesting case of subependymoma of the spinal cord

BACKGROUND CONTEXT

Subependymomas are rare, slow-growing, and usually noninvasive/nonaggressive World Health Organization Grade I tumors that tend to occur in the ventricles. Their most common site of occurrence is the fourth ventricle followed by the lateral ventricles. Spinal cord subependymomas typically manifest as cervical and cervicothoracic intramedullary or, rarely, extramedullary mass lesions. They often present clinically with pain and neurologic symptoms, including motor, sensory, urinary, and sexual dysfunction. Histologically, there are hypocellular areas with occasional clusters of cells and frequent microcystic changes, calcifications, and hemorrhage. Radiologically, subependymomas generally manifest as eccentric well circumscribed nodular lesions with mild-to-moderate enhancement.

PURPOSE

To highlight an interesting and rare presentation for subependymoma of the spinal cord.

STUDY DESIGN

This is a case report of a single patient in whom a subependymoma was resected from the cervical spinal cord with return to normal functioning.

METHODS

Clinical examination, magetic resonance imaging evaluation, surgical resection, and histological analysis were performed for diagnosis and treatment of this patient.

RESULTS

The patient experiencing myelopathy symptoms underwent a surgical resection of cervical spinal cord subependymoma that resulted in return to normal function.

CONCLUSIONS

Subependymoma should be included in the differential diagnosis of atypical presentations for myelopathy, as discrete surgical resection can result in good outcome.

Myxopapillary ependymoma masquerading as subcutaneous sacrococcygeal non-healing ulcer: case report

Ependymomas outside the confines of the cranium and spinal cord are rare. The occurrence of these tumors in an extradural, sacrococcygeal, or subcutaneous location may prove challenging, particularly in the absence of any obvious central nervous system connection. The origin of these tumors from sub.cutaneous sacrococcygeal ependymal rests is postulated on the basis of earlier reports. We describe 1 such rare extradural case of myxopapillary ependymoma in a 30-year-old female, which presented as a non-healing ulcer in the left gluteal area. It was initially diagnosed and was being treated as an infected epidermoid cyst. Clinical and histopathological features are described, and a brief review of published reports is presented.

Magnetic resonance image findings of primary intradural Ewing sarcoma of the cauda equina: case report and review of the literature

BACKGROUND CONTEXT

Involvement of the cauda equina in Ewing sarcoma (ES) is extremely rare, and only few cases are reported in literature. However, ES of cauda equina shares some neuroradiological features with other neoplasms that can involve the intradural space. Therefore, differential diagnosis with other tumors of cauda equina should be considered by neuroradiologists and neurosurgeons to provide appropriate treatment.

PURPOSE

To present a rare case of intradural extramedullary primary ES.

STUDY DESIGN

Case report.

METHODS

We report a case of a 44-year-old woman presenting with the rapid onset of cauda equina syndrome. Radiological analysis showed multiple intradural masses, extending from L1 to S3 level. After radical surgery, lesions were histologically defined as ES. We present a literature review, analyzing magnetic resonance image (MRI) features of primary intradural ES of the cauda equina.

RESULTS

Four cases of primitive ES arising from the cauda equina have been reported in the literature.

CONCLUSIONS

Because of the low number of reported cases, it is not possible to describe pathognomonic MRI findings for intradural ES of the cauda equina. However, few tumors show similar MRI features. Therefore, despite its rarity, intradural ES should be taken into account in the differential diagnosis of spinal tumors involving cauda equina.

Familial syndromes associated with intracranial tumours: a review

BACKGROUND

Most cancers of the central nervous system (CNS) occur sporadically in the absence of any known underlying familial disorder or multi-systemic syndrome. Several syndromes are associated with CNS malignancies, however, and their recognition has significant implications for patient management and prognosis. Patients with syndrome-associated CNS malignancies often have multiple tumours (either confined to one region or distributed throughout the body), with similar or different histology.

OBJECTIVE

This review examines syndromes that are strongly associated with CNS cancers: the phakomatosis syndromes, familial syndromes such as Li-Fraumeni and familial polyposis syndromes and dyschondroplasia.

Intradural spinal tumours and their mimics: a review of radiographic features

Intradural spinal tumours, although relatively uncommon, can be diagnostically challenging, and often result in significant morbidity. They can be subdivided according to their cell of origin and whether they are within the cord (intramedullary) or intradural but extramedullary in location. The differential diagnosis for masses of the cauda equina region is often considered separately. Additionally, some inflammatory processes, cysts, benign tumour-like masses and vascular malformations may mimic intradural tumours. Although in many instances, a precise preoperative diagnosis is not possible as many of the imaging findings overlap, some features may strongly suggest one diagnosis over others. This article reviews the range of intradural spinal tumours in the adult and paediatric populations, with an emphasis on pertinent imaging characteristics. An approach is provided for distinguishing tumours from lesions that mimic tumours and for narrowing the differential diagnosis according to imaging findings.

The isolation, differentiation, and survival in vivo of multipotent cells from the postnatal rat filum terminale

Neural stem cells (NSCs) are undifferentiated cells in the central nervous system (CNS) that are capable of self-renewal and can be induced to differentiate into neurons and glia. Current sources of mammalian NSCs are confined to regions of the CNS that are critical to normal function and surgically difficult to access, which limits their therapeutic potential in human disease. We have found that the filum terminale (FT), a previously unexplored, expendable, and easily accessible tissue at the caudal end of the spinal cord, is a source of multipotent cells in postnatal rats and humans. In this study, we used a rat model to isolate and characterize the potential of these cells. Neurospheres derived from the rat FT are amenable to in vitro expansion in the presence of a combination of growth factors. These proliferating, FT-derived cells formed neurospheres that could be induced to differentiate into neural progenitor cells, neurons, astrocytes, and oligodendrocytes by exposure to serum and/or adhesive substrates. Through directed differentiation using sonic hedgehog and retinoic acid in combination with various neurotrophic factors, FT-derived neurospheres generated motor neurons that were capable of forming neuromuscular junctions in vitro. In addition, FT-derived progenitors that were injected into chick embryos survived and could differentiate into both neurons and glia in vivo.

Intramedullary spinal cord metastases: MRI and relevant clinical features from a 13-year institutional case series

BACKGROUND AND PURPOSE

Because intramedullary spinal cord metastasis is often a difficult diagnosis to make, our purpose was to perform a systematic review of the MR imaging and relevant baseline clinical features of intramedullary spinal cord metastases in a large series.

MATERIALS AND METHODS

Consecutive patients with intramedullary spinal cord metastasis with available pretreatment digital MR imaging examinations were identified. The MR imaging examination(s) for each patient was reviewed by 2 neuroradiologists for various imaging characteristics. Relevant clinical data were obtained.

RESULTS

Forty-nine patients had 70 intramedullary spinal cord metastases, with 10 (20%) having multiple intramedullary spinal cord metastases; 8% (4/49) were asymptomatic. Primary tumor diagnosis was preceded by intramedullary spinal cord metastasis presentation in 20% (10/49) and by intramedullary spinal cord metastasis diagnosis in 10% (5/49); 98% (63/64) of intramedullary spinal cord metastases enhanced. Cord edema was extensive: mean, 4.5 segments, 3.6-fold larger than enhancing lesion, and ≥3 segments in 54% (37/69). Intratumoral cystic change was seen in 3% (2/70) and hemorrhage in 1% (1/70); 59% (29/49) of reference MR imaging examinations displayed other CNS or spinal (non-spinal cord) metastases, and 59% (29/49) exhibited the primary tumor/non-CNS metastases, with 88% (43/49) displaying ≥1 finding and 31% (15/49) displaying both findings. Patients with solitary intramedullary spinal cord metastasis were less likely than those with multiple intramedullary spinal cord metastases to have other CNS or spinal (non-spinal cord) metastases on the reference MR imaging (20/39 [51%] versus 9/10 [90%], respectively; P = .0263).

CONCLUSIONS

Lack of known primary malignancy or spinal cord symptoms should not discourage consideration of intramedullary spinal cord metastasis. Enhancement and extensive edema for lesion size (often ≥3 segments) are typical for intramedullary spinal cord metastasis. Presence of cystic change/hemorrhage makes intramedullary spinal cord metastasis unlikely. Evidence for other CNS or spinal (non-spinal cord) metastases and the primary tumor/non-CNS metastases are common. The prevalence of other CNS or spinal (non-spinal cord) metastases in those with multiple intramedullary spinal cord metastases is especially high.

[Radiological diagnostics of spinal tumors. Part 2: special diagnostics of intradural tumors and tumor-like lesions]

Intradural tumors are classified into extramedullary and intramedullary localization. A distinct attribution to one of these compartments is essential for finding the appropriate diagnosis. In the radiological evaluation of intradural tumors magnetic resonance imaging (MRI) is the most important method and in contrast to osseous spinal tumors, radiography and computed tomography are of minor importance. According to the globally established WHO grading system, tumors of the central nervous system are histopathologically classified into four grades. Through grades I to IV malignancy and proliferative activity increase. Prognosis is inversely correlated to the WHO grade. Intradural tumors are generally treated by neurosurgeons. Besides neurological symptoms intradural tumors often cause spinal malpositioning. Thus knowledge of the most frequent intradural tumors and their characteristic magnetic resonance findings are important in the orthopedic practice.

A Nonenhancing World Health Organization Grade II Intramedullary Spinal Ependymoma in the Conus: Case Illustration and Review of Imaging Characteristics

Spinal ependymomas comprise ~60% of all intramedullary tumors in adults. Ependymomas demonstrate distinct imaging features, such as central location within the spinal cord, symmetrical expansion, intra- and extratumoral cysts, hemosiderin caps, and strong enhancement on contrast-injected, T1-weighted magnetic resonance (MR) imaging. In adults, most ependymomas are myxopapillary, and in children, most are nonmyxopapillary. In general, nonmyxopapillary or classic ependymomas are hyperintense on T2- and hypointense on T1-weighted MR imaging, but whereas the signal intensity on T1 and T2 is variable, homogeneous contrast enhancement is usually a characteristic finding. Here, the authors provide an overview on spinal ependymomas with an emphasis on imaging characteristics and morphological background and present the case of a World Health Organization grade II ependymoma in the conus that did not enhance. Interestingly, the tumor contained a large hemorrhagic cyst. Just as hemorrhagic metastatic tumors may not enhance, a hemorrhagic ependymoma may likewise not enhance after administration of contrast agent. Thus, the differential diagnosis of a nonenhancing intramedullary lesion in the conus should include ependymoma, particularly if there is concomitant hemorrhage.

Spinal tanycytic ependymoma with diffusion restriction on MRI

Tanycytic ependymoma is a rare spindle-cell variant of ependymoma derived from tanycytes. Primitive neuroectodermal tumors usually have diffusion restriction, whereas ependymomas do not. Here, we present a case of tanycytic ependymoma with diffusion restriction. As far we are aware, this is the first case of tanycytic ependymoma in the English literature with diffusion restriction.

Complications associated with the treatment for spinal ependymomas

Spinal cord ependymomas are rare neoplasms, comprising approximately 5% of all CNS tumors and 15% of all spinal cord tumors. Although surgery was once reserved for diagnosis alone, the evolution of surgical practices has elevated resection to the treatment of choice for these lesions. While technological advances continue to improve the capacity for gross-total resections and thus decrease the risk of recurrence, ependymoma spinal surgery still contains a variety of potential complications. The presence of neurological deficits and deterioration are not uncommonly associated with spinal cord ependymoma surgery, including sensory loss, dorsal column dysfunction, dysesthetic syndrome, and bowel and bladder dysfunction, particularly in the immediate postoperative period. Surgical treatment may also lead to wound complications and CSF leaks, with increased risk when radiotherapy has been involved. Radiation therapy may also predispose patients to radiation myelopathy and ultimately result in neurological damage. Additionally, resections of spinal ependymomas have been associated with postoperative spinal instability and deformities, particularly in the pediatric population. Despite the advances in microsurgical techniques and intraoperative cord monitoring modalities, there remain a number of serious complications related to the treatment of spinal ependymoma tumors. Identification and acknowledgment of these potential problems may assist in their prevention, early detection, and increased quality of life for patients afflicted with this disease.

Osseous erosion by herniated nucleus pulposus mimicking intraspinal tumor: a case report

Erosion of spinal osseous structure, so-called scalloping, has been rarely reported associated with herniated nucleus pulposus (HNP). We report a rare case of HNP causing erosion of the spinal osseous structure (including lamina). The patient was an 81-year-old woman with 3-year history of low-back pain and left leg radiating pain. Muscle weakness of the left leg was also apparent. Computed tomography following myelography showed severe compression of the dural sac at the level of L3–L4; furthermore, erosion of the lamina, pedicle, and vertebral body was noted, indicating that the space-occupying mass was most probably a tumorous lesion. The mass also showed calcification inside. During the surgery, the mass was confirmed to be an HNP with calcification. Following resection, the pain disappeared. Surgeons should be aware of the possibility of scalloping of the vertebrae caused by HNP mimicking a tumorous lesion.

[Imaging of demyelinating and neoplastic diseases of the spinal cord]

The clinical symptoms of myelopathy are variable and non-specific. Demyelinating as well as neoplastic spinal cord diseases can cause paresthesia, progressive sensomotoric deficits and bowel and bladder dysfunction. Imaging of the spine, especially with magnetic resonance imaging (MRI), is an essential component in the diagnostic assessment of myelopathy and makes a substantial contribution to achieving the correct diagnosis. Although intramedullary neoplasms are far less common than demyelinating spinal cord diseases, radiologists should be familiar with the three most common entities, astrocytoma, ependymoma and hemangioblastoma, which represent over 70% of all spinal cord neoplasms. An early diagnosis and therapy is essential with neoplastic and demyelinating spinal cord diseases to hold residual neurological deficits as low as possible.

Magnetic resonance imaging of intramedullary spinal cord lesions: a pictorial review

Magnetic resonance imaging is the current imaging modality of choice in the evaluation of patients presenting with myelopathic symptoms in the search for spinal cord lesions. It is important for the radiologist to recognize and differentiate nonneoplastic from the neoplastic process of the spinal cord as the differentiation of the 2 entities is extremely crucial to the neurosurgeon. This article presents a broad spectrum of benign intramedullary spinal abnormalities including syrinx, contusion, abscess, infarction, myelitis, multiple sclerosis, sarcoid, cavernoma, and arteriovenous malformation. Rare intramedullary neoplasms including dermoid tumor, astrocytoma, ependymoma, hemangioblastoma, lymphoma, ganglioneuroblastoma, and metastases are also illustrated. The clinical presentation and magnetic resonance signal characteristics as well as the differential diagnosis of the intramedullary lesions are discussed. The potential pitfalls in the differentiation of tumors from nonneoplastic disease of the spinal cord are also elucidated.