|Year : 2014 | Volume
| Issue : 4 | Page : 748-751
Role of MRI in evaluation of intraspinal tumors
Mohamed Yasin MBBCh , Mohamed Shawky, Zeinab Abd Elaziz
Radiology Department, Faculty of Medicine, Menoufia University, Menoufia, Egypt
|Date of Submission||09-Feb-2014|
|Date of Acceptance||10-Apr-2014|
|Date of Web Publication||22-Jan-2015|
Radiodiagnosis Department, Faculty of Medicine, Menoufia University, Menoufia
Source of Support: None, Conflict of Interest: None
This study aimed to evaluate the importance of MRI as a noninvasive diagnostic tool in patients with spinal tumors and to correlate the MRI findings with the patients' neurological outcome.
Radiographic evaluation is crucial in patients with spinal tumor. A correct investigation can establish the diagnosis and early surgery gives a better chance for full recovery. MRI became the gold standard for imaging neurological tissues including the spinal cord. MRI serves as a problem-solving technique to assess the cause of neurological deficits.
Materials and methods
This prospective study included 50 patients with neurological deficit. The following MR sequences were performed to all patients: sagittal T1WIs and T2WIs, axial T1WIs and T2WIs, axial T1WI, and sagittal T1WI after contrast injection. Data of spinal symptoms were collected, analyzed, and correlated with findings on neurological examination.
The total number of patients was 50 and male-to-female ratio was 32 : 18; the age ranged between 3 and 75 years. Lumbar spine was the commonest site of injury (40%). The commonest type of spinal tumors was metastasis (42%). Vertebral bone involvement was in more than half of the patient (54%). Most of the tumors show hypointense signal on T1WI (70%), hyperintense signal on T2WI (86%), and postcontrast homogeneous enhancement (60%).
MRI is strongly recommended for accurate diagnosis of spinal tumors because of its many advantages such as higher contrast resolution, absence of bony artifacts, and multiplanar capability. More information about neural and extraneural lesions can be obtained.
Keywords: MRI, spinal tumors, neurological deficits, MRI spinal tumours
|How to cite this article:|
Yasin M, Shawky M, Elaziz ZA. Role of MRI in evaluation of intraspinal tumors. Menoufia Med J 2014;27:748-51
| Introduction|| |
Intraspinal tumors can conveniently be grouped into categories as determined by the neoplasm's location as intramedullary, intradural/extramedullary, and extradural .
Intraspinal tumor with spinal cord compression is a major cause of morbidity in patients with cancer. The outcome of treatment is poor, with less than half of patients retaining or regaining the ability to walk and about 40% requiring a permanent urinary catheter. Delay in diagnosis and treatment is common and is associated with deterioration in functional status and consequent poor functional outcome .
Great advances in radiological imaging of spinal tumors have occurred over the past 20 years; imaging is now a crucial component in diagnosis and treatment planning. A variety of imaging modalities are now widely available. Plain film radiographs are usually included in the initial evaluation of patients with spinal tumors, providing information about osseous anatomy .
| Materials and methods|| |
This prospective study was conducted on 50 patients with spinal tumors presenting various symptoms and signs of neurological deficit; there were 32 male patients and 18 female patients with age ranging between 3 and 75 years. All patients underwent complete history taking and full neurological examination by the clinician. All patients underwent MRI examination of the spine.
Protocol of the MR scan of the spine
MRI of the spine was performed in the axial and sagittal planes using a combination of pulse sequences. The study was performed while patients lying supine with their median sagittal plane coinciding with the midline of the scanner table. We performed all MR scans with a 1.5-T closed MR scanner (Excelart, Vantage, and Toshiba Medical Systems).
A circular surface (synergy body) coil was used to obtain a high signal-to-noise ratio and high spatial resolution. The sequences performed are shown in [Table 1].
Paramagnetic contrast gadopentetate dimeglumine diethylenetriaminepenta-acetic acid (Gd-DTPA) was given at a dose of 0.1 mmol/kg body weight to a maximum dose of 20 ml through intravenous cannula, during 1 min. The examination started immediately at the end of injection. The scanning time varied from 25 to 50 min.
| Results|| |
The total number of patients was 50 and male-to-female ratio was 32 : 18; the age ranged between 3 and 75 years. Lumbar spine was the commonest site of the tumors (40%), followed by dorsal spine (36%), then the cervical spine (14%).
The commonest spinal tumors was metastasis [21 cases (42%)] followed by lymphoma [eight cases (16%)], five cases (10%) were astrocytoma, two cases (4%) were lipoma, four cases (8%) were ependymoma, two cases (4%) were meningioma, four cases (8%) were neurofibroma, one case (2%) was neuroblastoma, and two cases (4%) were chondrosarcoma.
A total of 35 cases (70%) showed hypointense signal on T1 and 43 (86%) showed hyperintense signal on T2 with respect to the cord.
In our study, vertebral bone involvement was in more than half of the patients [27 cases (54%)], homogeneous enhancement after contrast injection was in 30 cases (60%), and the commonest association was cystic degeneration in five cases (10%).
| Discussion|| |
In our study, the extradural lesions were the commonest intraspinal tumors representing about 54% of cases, followed by intradural extramedullary lesions representing 24% of cases, then intradural intramedullary lesions representing 22% of cases.
This is in agreement with the study by Han et al.  who showed that extradural tumors of the spine (including metastases) represent about 42.8%, intradural extramedullary tumors represent about 35.7%, whereas intramedullary tumors represent about 21.5% of the spinal tumors.
In our study, the histopathology of the studied patients revealed that the commonest metastatic lesion was bronchogenic carcinoma (10%) and undifferentiated carcinoma (10%) followed by breast (8%), prostate (4%), and then Ewing sarcoma, pontine glioma, and leukemia (2%).
Shah and Salzman  stated that metastases to the spine can involve the bone, epidural space, leptomeninges, and the spinal cord. The spine is the third most common site for metastatic disease, following the lung and the liver, and it is the most common osseous site. Approximately, 60-70% of patients with systemic cancer will have spinal metastasis. Common tumors with a high rate of metastasis to bone include tumors of the breast (72%), prostate (84%), thyroid (50%), lung (31%), kidney (37%), and pancreas (33%). Together, these account for more than 80% of primary tumors in patients presenting with metastases .
In our study, metastatic extradural tumors were isointense (four cases) and hypointense (11 cases) on T1 and 10 cases hyperintense, two cases hypointense, and three cases isointense on T2. This is in agreement with the study by Latchaw et al.  who reported that a metastasis will have lower signal than marrow on a T1-weighted image and higher signal on a T2-weighted image.
In our study, there were eight cases of lymphoma with male predominance; the age ranged from 44 to 67 years. The commonest site of lymphoma was dorsal (four cases), followed by lumbar (three cases) and cervical (one case), and their signals were hypointense (seven cases) and isointense (one case) on T1 and hyperintense (eight cases) on T2. Seven cases of lymphoma showed homogeneous enhancement after contrast injection and one case showed heterogeneous enhancement.
This agrees with the study by Bloomer et al.  who stated that, on MR, lymphoma appears as single or multifocal, ill-defined T2W/FLAIR hyperintense lesions with homogeneous contrast enhancement on T1W images. Because of high cell tumor density, diffusion-weighted MRI often demonstrates restriction .
In our study, there were two female patients with meningioma accounting for 16% of intradural extramedullary tumors; they were seen at the cervical and the dorsal regions, and the age ranged between 40 and 46 years. They were isointense on T1W and one was hyperintense on T2 and the second was isointense on T2W; one of them showed calcification on computed tomographic study.
This agrees with the study by Arnautovic and Arnautovic  who stated that spinal meningiomas are isointense or hypointense on T1-weighted images and slightly hyperintense on T2-weighted MRI. Upon contrast application, they enhance vividly (except for a calcified part) and frequently display a 'dural tail' sign. Only 5% of meningiomas may present in a dumbbell shape .
In our study, there were two cases of intradural extramedullary lipoma, one at the lumbar region and the second at the filum terminale, which was associated with tethered cord. Both lesions were hyperintense on T1W and less hyperintense on T2WI with no enhancement after contrast injection.
This agrees with the study by Bloomer et al.  who stated that lipoma appears hyperintense on T1WIs and relatively low on T2WIs and suppresses on fat-suppressed images.
In our study, there were five cases of astrocytoma found in the cervical (four cases) and dorsal regions (one case). They showed isointensity to the cord (two cases), hypointensity (three cases) on T1WI, and hyperintensity (five cases) on T2WI with homogeneous enhancement after contrast injection. They were associated with syrinx in two cases and cystic degeneration in one case.
In our study, there were four cases of ependymoma found in the cervical (one case), lumbar (two cases), and the filum terminal (one case). They showed isointensity to the cord (one case), hypointensity (three cases) on T1WI, and hyperintensity (four cases) on T2WI with homogeneous enhancement in two cases, heterogeneous in one case, and marginal enhancement in one case. They were associated with cystic degeneration in three cases.
This is in agreement with the studies by Nemoto et al.  and Fulbright et al.  who reported that, on MRI, both ependymomas and astrocytomas were hypointense on T1W and hyperintense on T2W images with nonhomogeneous signals, and hyperintense rim was present around the ependymomas in both sequences; this hyperintense rim-associating ependymoma was defined as pseudocapsule formed by repeated hemorrhages in the interface between the tumor and the normal cord.
Kocher et al.  stated that ependymoma is most common in the cervical region (44%), followed by the thoracic (23%) and less common in the distal thoracic cord or conus medullaris (6.5%). Astrocytomas are most commonly located in the thoracic region, followed by the cervical cord, and rarely present as an isolated or focal lesion in the conus. In children, involvement of the entire cord is common; however, this is rare in adults.
| Conclusion|| |
MRI is crucial in patients with spinal tumors for assessment of the spinal cord and osseous and soft tissue structures. This is especially important when an accurate clinical examination and history are limited because of soft tissue swelling or disturbed consciousness level.
The various MR findings in spinal cord tumors are correlated well with the pathological findings. MRI is useful for initial diagnosis of spinal cord tumors and its prognosis for predicting neurological recovery.
Many advantages of MRI, such as higher contrast resolution, multiplanar capability, and choice of various pulse sequences, make it possible to diagnose spinal tumors more accurately. It provides more adequate information about neural and extraneural lesions requiring surgical interventions.
This study recommends that MR scanning of the spine should be performed for any proven spinal tumors or any patient presenting with neurological deficit of either sensory or motor manifestations.
Because of the frequency of adjacent tissue extensions in patients with spinal tumors, we recommend proper imaging of the spine with larger field of view [Figure 1] and [Figure 2].
|Figure 1: Case no. 1: (a) Sagittal T1WI, (b) Sagittal T2WI, and (c) Axial T2W1 demonstrate extradural tumor at the level of LV4 compressing the thecal sac with vertebral bone involvement at LV4 and show hypointense signal on T1WI and T2WI. (d) Axial T1WI postcontrast shows no contrast enhancement after intravenous contrast injection.|
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|Figure 2: Case no. 2: (a) Sagittal T1WI, (b) Sagittal T2WI, and (c) Axial T2W1 demonstrate an intramedullary mass at the level of LV3 and show isointense signal on T1WI and slightly hypointense on T2WI. (d) Axial T1WI and (e) Sagittal T1WI postcontrast show homogeneous enhancement after intravenous contrast.|
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| Acknowledgements|| |
Conflicts of interest
There are no conflicts of interest.
| References|| |
Hussein HA, Goda HA. Paravertebral neurogenic tumors with intraspinal extension: preoperative evaluation and surgical approach. J Egypt Natl Canc Inst 2009; 21
Husband DJ, Grant KA, Romaniuk CS. MRI in the diagnosis and treatment of suspected malignant spinal cord compression. Br J Radiol 2001; 74
Bloomer CW, Ackerman A, Bhatia RG. Imaging for spine tumors and new applications. Top Magn Reson Imaging 2006; 17
Han JS, Koufman B, Yousef SJ, Benson JE, Bonstelle CT, Alfidi RJ. NMR imaging of the spine. Am J Roentgenol 1983; 141
Shah LM, Salzman KL. Imaging of spinal metastatic disease. Int J Surg Oncol 2011; 2011: 769753.
Latchaw RE, Charles AJ, William ER. Tumors and infection of the spine and spinal cord: MR & CT imaging of the head. Neck Spine 1991; 177
Arnautovic K, Arnautovic A. Extramedullary intradural spinal tumors: a review of modern diagnostic and treatment options and a report of a series. Bosn J Basic Med Sci 2009; 9
Nemoto Y, Inoue Y, Tashiro T, Mochizuki K, Oda J, Kogame S, et al.. Intramedullary spinal cord tumors: significance of associated hemorrhage at MR imaging. Radiology 1992; 182
Fulbright R, Ross JS, Sze G. Application of contrast agents in MR imaging of the spine. J Magn Reson Imaging 1993; 3
Kocher B, Smirniotopoulos JG, Smith AB. Intradural spinal lesions. Applied Radiology© 2009; Available at: http://www.appliedradiology.com
. [Last accessed on 2012 Mar 3].
[Figure 1], [Figure 2]