Magnetic Resonance Myelography Research Articles

Role of FIESTA combined with conventional MRI in the evaluation of traumatic brachial plexus roots injury

PurposePurpose was to evaluate the role of Fast imaging employing steady-state acquisition (FIESTA) together with conventional MR sequences in the evaluation of traumatic brachial plexus roots injury compared to post contrast MR and Spin Echo MR myelographic studies. Patients and methodsIn this prospective study, 16 patients with a mean age of 17.9y who presented with traumatic brachial plexus roots injury in motor cycle and car accidents were studied with FIESTA, conventional MR, post contrast MR and MR myelography sequences. Imaging findings included: pseudo-meningocele/hemorrhage near the nerve root exit, failure of visualization of the nerve root (dorsal, ventral or both), retracted avulsed nerve root ends, spinal cord edema, and para spinal muscles edema and hemorrhage. Diagnostic accuracy was calculated for each MR sequence. Imaging findings were compared with the gold standard operative findings. ResultsFIESTA combined with conventional MR depicted pseudomeningoceles, non visualized nerve roots, cord displacement, and para spinal muscles abnormalities in 15 patients (93.8%), cord edema in four patients (25%). Pre and post contrast MR detected pseudomeningoceles and non visualized nerve roots in 13 patients (81.3%) while Spin Echo myelography detected pseudomeningoceles and non visualized nerve roots in 14 patients (87.5%). FIESTA combined with conventional MR showed the highest diagnostic accuracy (93.8%) compared to pre and post MR (81.3%) and Spin Echo myelography (87.5%). ConclusionIt is crucial to differentiate between preganglionic and postganglionic injuries for optimal treatment planning in patients with BPI. Conventional MR imaging yielded suboptimal information regarding the fine details of nerve roots’ injury. MR myelography showed some artifacts that decreased overall diagnostic accuracy, FIESTA combined with conventional MR depicted nerve segments in greater detail and provided important information about the relationship of the nerves to nearby structures, it provided high contrast resolution between cerebrospinal fluid and solid structures, allowing the reconstruction of elegant multi-planar images that highlight the injured nerves. Contrast study is recommended in mild trauma cases with normal morphological study.

Comparison Between MRI and Myelography in Lumbar Spinal Canal Stenosis for the Decision of Levels of Decompression Surgery

A retrospective case-control study. To investigate differences between number of levels of decompression surgery for lumbar spinal canal stenosis (LSCS) as decided by magnetic resonance imaging (MRI) and myelography with computed tomographic myelography (CTM), and to investigate intraobserver reliability and interobserver reproducibility of MRI and myelography with CTM. Although the decision to carry out decompression surgery for LSCS largely depends on the severity of stenosis on imaging along with clinical findings, no universally accepted imaging criteria have been defined for determining severity of LSCS. The decision to carry out decompression surgery for LSCS thus seems relatively subjective, and would differ according to both observer and the findings of preoperative imaging. We retrospectively selected 50 patients with LSCS who underwent decompression surgery. Mean patient age was 69 years, and mean number of levels carried out decompression surgery was 2. Each of 4 spine surgeons retrospectively decided levels of decompression surgery 4 times, according to the findings of MRI or myelography with CTM (MRI-1, MRI-2, CTM-1, CTM-2). We investigated differences between number of levels of decompression surgery decided by MRI and myelography with CTM, and also investigated intraobserver reliability and interobserver reproducibility of MRI and myelography with CTM. The number of levels of decompression surgery as decided by myelography with CTM was significantly greater than that by MRI. κ coefficients for intraobserver reliability and interobserver reproducibility revealed myelography with CTM as more reliable and reproducible than MRI. The number of levels of decompression surgery for LSCS as decided by MRI would be less than that by myelography with CTM. Myelography with CTM is more reliable and reproducible than MRI for preoperative evaluation of LSCS.

Detection of CSF leaks with magnetic resonance imaging in intracranial hypotension syndrome

Intracranial hypotension syndrome (IHS) is a rare disorder characterized by postural headache, low cerebrospinal fluid (CSF) pressure, dural thickening and pachymeningeal contrast enhancement as a consequence of decreased CSF volume. The present report is a case of spontaneous IHS due to dural leak at the level of T12-L1. The site of CSF leakage was not detectable on either conventional magnetic resonance imaging (MRI) or T2-weighted MR myelography. However, it was evident on contrast-enhanced MR myelography (CE-MRM). The present report discusses the efficacy of CE-MRM in the detection of CSF leaks according to the literature so far.

Characteristic MRI and MR Myelography Findings for the Facet Cyst Hematoma at T12-L1 Spine: A Case Report

A facet cyst is a very rare condition in the thoracolumbar spine and more so, hemorrhage into a cyst is extremely rare. We present a case of a facet cyst hematoma in the T12-L1 spine. A 69-year-old woman complained of chronic back pain with right lower extremity pain, and weakness for 3 years. MRI and MR myelography showed an extradural mass at the T12-L1 level with heterogeneous signal intensity on both T1-and T2-weighted images, which was continuous to the right T12-L1 facet joint. The neighboring facet joint showed severe degeneration on the CT scan. The mass a was simple hematoma covered with a thin fibrous membrane and connected with facet joint macroscopically and microscopically. The pathogenesis of the facet cyst hematoma is not clear but it can compress nerve roots or dura mater and cause radiculopathy or cauda equina syndrome. Surgical removal should be recommended for symptomatic relief.

Postpuncture CSF leakage

We sought to evaluate radioisotope cisternography (RICG)-related postpuncture CSF leakage by MRI. We conducted a prospective 3-day imaging study. Ten patients with orthostatic headache and other symptoms underwent pre-RICG brain and spinal MRI, magnetic resonance myelography (MRM), RICG, and post-RICG spinal MRI and MRM. For RICG, we used a 25-gauge pencil point spinal needle at the L3/4 or L4/5 level after which subjects took bed rest for 2.5 hours. On pre-RICG MRI and MRM, none of the 10 patients showed CSF leakage. However, 5 subjects (50%) showed epidural abnormalities suggesting CSF leakage on MRI after lumbar puncture for RICG. On RICG and subsequent MRM, 4 of the subjects showed definite findings of CSF leakage and 1 showed minimal leakage. RICG carries a risk of iatrogenic CSF leakage even with careful puncturing using a fine needle. This leakage produces abnormal RICG and MRM findings at the lumbosacral level. Therefore, abnormal RICG findings restricted to the lumbosacral level should be carefully interpreted when diagnosing SIH.

Magnetic resonance myelography in early postoperative lumbar discectomy: An efficient and cost effective modality

Background:Magnetic resonance myelography (MRM) after lumbar discectomy is all too often an unrewarding challenge. A constellation of findings are inevitable, and determining their significance is often difficult. MRM is a noninvasive technique that can provide anatomical information about the subarachnoid space. Until now, there is no study reported in literature showing any clinico-radiological correlation of post operative MRM. The objective of this study was to prospectively evaluate the diagnostic effectiveness of MRM for the demonstration of decompression in operated discectomy patients and its correlation with subjective and objective outcome (pain and SLR) in immediate postoperative period.Materials and Methods:Fifty three patients of single level lumbar disc herniation (LDH) justifying the inclusion criteria were operated for discectomy. All patients underwent MRM on second/third postoperative day. The pain relief and straight leg raise sign improvement was correlated with the postoperative MRM images to group the patients into: A- Subjective Pain relief, SLR improved and MRM image showing myelo regression; B- Subjective Pain relief, SLR improved and MRM image showing no myelo regression; C- No Subjective Pain relief, no SLR improved and MRM image showing myelo regression and; D- No Subjective Pain relief, no SLR improved and MRM image showing no myelo regression.Results:The result showed that Group A had 46 while Group B, C and Group D had 4, 2 and one patients respectively. Clinico-radiological correlation (Clinically diagnosed patient and findings with MRM correlation) was present in 47 patients (88.68%) which includes both A and D groups. The MRM specificity and sensitivity were 92% and 33.33% respectively.Conclusion:MRM is a non-invasive, efficient and reliable tool in confirming postoperative decompression in lumbar discectomy patients, especially when economic factors are to be considered and the required expertise to reliably read a complex confusing post-operative MRI is not available readily. Further, controlled double blinded multicentric study in operated and non operated LDH, with MRI comparison would give better evidence to justify its use in screening to detect persisting compression and to document decompression.

New approaches in imaging of the brachial plexus

Imaging plays an essential role for the detection and analysis of pathologic conditions of the brachial plexus. Currently, several new techniques are used in addition to conventional 2D MR sequences to study the brachial plexus: the 3D STIR SPACE sequence, 3D heavily T2w MR myelography sequences (balanced SSFP = CISS 3D, True FISP 3D, bFFE and FIESTA), and the diffusion-weighted (DW) neurography sequence with fiber tracking reconstruction (tractography). The 3D STIR sequence offers complete anatomical coverage of the brachial plexus and the ability to slice through the volume helps to analyze fiber course modification and structure alteration. It allows precise assessment of distortion, compression and interruption of postganglionic nerve fibers thanks to the capability of performing maximum intensity projections (MIP) and multiplanar reconstructions (MPRs). The CISS 3D, b-SSFP sequences allow good visualization of nerve roots within the spinal canal and may be used for MR myelography in traumatic plexus injuries. The DW neurography sequence with tractography is still a work in progress, able to demonstrate nerves tracts, their structure alteration or deformation due to pathologic processes surrounding or located along the postganglionic brachial plexus. It may become a precious tool for the understanding of the underlying molecular pathophysiologic mechanisms in diseases affecting the brachial plexus and may play a role for surgical planning procedures in the near future.

Practice Advisory for the Prevention, Diagnosis, and Management of Infectious Complications Associated with Neuraxial Techniques

Practice Advisory for the Prevention, Diagnosis, and Management of Infectious Complications Associated with Neuraxial Techniques

Comparative Study of Lumbar Magnetic Resonance Imaging and Myelography in Young Soldiers with Herniated Lumbar Disc

This study was undertaken to compare the diagnostic performances of magnetic resonance imaging (MRI), MR myelography (MRM) and myelography in young soldiers with a herniated lumbar disc (HLD). Sixty-five male soldiers with HLD comprised the study cohort. A visual analogue scale for low back pain (VAS-LBP), VAS for leg radiating pain (VAS-LP), and Oswestry disability index (ODI) were applied. Lumbar MR, MRM, and myelographic findings were checked and evaluated by four independent radiologists, respectively. Each radiologist was asked to score (1 to 5) the degree of disc protrusion and nerve root compression using modified grading systems devised by the North American Spine Society and Pfirrmann and the physical examination rules for conscription in the Republic of Korea. Correlated coefficients between clinical and radiological factors were calculated. Interpretational reproducibility between MRI and myelography by four bases were calculated and compared. Mean patient age was 20.5 ± 1.1. Mean VAS-LBP and VAS-LP were 6.7 ± 1.6 and 7.4 ± 1.7, respectively. Mean ODI was 48.0 ± 16.2%. Mean MRI, MRM, and myelography scores were 3.3 ± 0.9, 3.5 ± 1.0, and 3.9 ± 1.1, respectively. All scores of diagnostic performances were significantly correlated (p < 0.05). However, none of these scores reflected the severity of patients' symptoms. There was no statistical difference of interpretational reproducibility between MRI and myelography. Although MRI and myelography are based on different principles, they produce similar interpretational reproducibility in young soldiers with a HLD. However, these modalities do not reflect the severity of symptoms.

New advances on diagnostic imaging in spinal pathology

In the past years, there has been a remarkable improvement on imaging technology. Magnetic resonance (MR) is the method of choice for detection, diagnosis and therapeutic management for many disorders of the spine. A variety of innovative new MR methods have been developed. These new techniques include molecular diffusion sequences, MR myelography, a complete study of the entire spine, kinematic MR imaging of the spine, whole body MR exam and the fusion of different imaging modalities. These new technological developments have the potential to profoundly impact and modify imaging interpretation to offer a more efficient diagnostic and work-up of patients suffering from spinal disease.

Heavily T2-weighted MR myelography vs CT myelography in spontaneous intracranial hypotension

Heavily T2-weighted MR myelography vs CT myelography in spontaneous intracranial hypotension

Heavily T2-weighted MR myelography vs CT myelography in spontaneous intracranial hypotension

To assess the diagnostic accuracy of heavily T2-weighted magnetic resonance myelography (MRM) in patients with spontaneous intracranial hypotension (SIH). Patients with SIH were recruited prospectively, and first underwent MRM and then computed tomographic myelography (CTM). The results of MRM were validated with the gold standard, CTM, focusing on 1) CSF leaks along the nerve roots, 2) epidural CSF collections, and 3) high-cervical (C1-3) retrospinal CSF collections. Comparisons of these 3 findings between the 2 studies were made by kappa statistics and agreement rates. Targeted epidural blood patches (EBPs) were placed at the levels of CSF leaks if supportive treatment failed. Nineteen patients (6 men and 13 women, mean age 37.9 +/- 8.6 years) with SIH completed the study. MRM did not differ from CTM in the detection rates of CSF leaks along the nerve roots (84% vs 74%, p = 0.23), high-cervical retrospinal CSF collections (32% vs 16%, p = 0.13), and epidural CSF collections (89% vs 79%, p = 0.20). MRM demonstrated more spinal levels of CSF leaks (2.2 +/- 1.7 vs 1.5 +/- 1.5, p = 0.011) and epidural collections (12.2 +/- 5.9 vs 7.1 +/- 5.8, p < 0.001) than CTM. The overall level-by-level concordance was substantial for CSF leaks along the nerve roots (C1-L3) (kappa = 0.71, p < 0.001, agreement = 95%) and high-cervical retrospinal CSF collections (C1-3) (kappa = 0.73, p < 0.001, agreement = 92%), and moderate for epidural CSF collections (C1-L3) (kappa = 0.47, p < 0.001, agreement = 72%). Ten of the 14 patients (71%) receiving targeted EBPs experienced sustained symptomatic relief after a single attempt. Heavily T2-weighted magnetic resonance myelography was accurate in localizing CSF leaks for patients with spontaneous intracranial hypotension. This noninvasive technique may be an alternative to computed tomographic myelography before targeted epidural blood patches.

MRI features of hydatid disease of the spine

Objective To analyze the typical MRI findings and to evaluate the value of MRI in the diagnosis of hydatid disease of the spine. Methods This retrospective study consisted of 16 patients with hydatidosis of the spine evaluated with MRI. All patients had surgery with histological diagnosis. MR myelography (MRM) was done in 4 cases, contrast-enhanced scan in 2 cases and perfusion weighted imaging (PWI) in 1 case. X-ray was performed in 8 cases and CT in 5 cases. Results All 16 cases were diagnosed as hydatid disease with multicysts. Hydatid disease involved thoracic spine in 5 cases, lumbar spine in 4 cases, sacrum in 3 cases, lumbnsacral spine in 2 cases and a combination of thoracic, lumbar spine and sacrum in 2 cases. MR imaging showed bone destruction with wedge shaped compression of single or multiple vertebra. The lesions were round in contour with different sizes and involved the bony spinal canal, appendix of vertebra and neighboring soft tissues. Cystic lesions with multiple daughter cysts demonstrated long T1 and long T2 abnormal signal intensity on MR imaging. On T2-weighted images, a hypointense rim was seen. Cystic lesions were better seen on T2 SPIR and MRM. Mild contrast enhancement of these lesions were seen. A single case showed iso-perfusion on PWI. Conclusions MRI can demonstrate hydatid cysts in vertebra, spinal canal, paravertebral and neighboring soft tissue. MRI is a valuable tool in the diagnosis and treatment planning of hydatid disease of the spine. Key words: Hydatid disease; Spine; Magnetic resonance imaging

Nuevos avances en el diagnóstico por imagen de la enfermedad del raquis

In the past years, there has been a remarkable improvement on imaging technology. Magnetic resonance (MR) is the method of choice for detection, diagnosis and therapeutic management for many disorders of the spine. A variety of innovative new MR methods have been developed. These new techniques include molecular diffusion sequences, MR myelography, a complete study of the entire spine, kinematic MR imaging of the spine, whole body MR exam and the fusion of different imaging modalities. These new technological developments have the potential to profoundly impact and modify imaging interpretation to offer a more efficient diagnostic and work-up of patients suffering from spinal disease.

Contrast-enhanced MR myelography in spontaneous intracranial hypotension: description of an artefact imitating CSF leakage

In contrast-enhanced (CE) MR myelography, hyperintense signal outside the intrathecal space in T1-weighted sequences with spectral presaturation inversion recovery (SPIR) is usually considered to be due to CSF leakage. We retrospectively investigated a hyperintense signal at the apex of the lung appearing in this sequence in patients with SIH (n = 5), CSF rhinorrhoea (n = 2), lumbar spine surgery (n = 1) and in control subjects (n = 6). Intrathecal application of contrast agent was performed in all patients before MR examination, but not in the control group. The reproducible signal increase was investigated with other fat suppression techniques and MR spectroscopy. All patients and controls showed strongly hyperintense signal at the apex of the lungs imitating CSF leakage into paraspinal tissue. This signal increase was identified as an artefact, caused by spectroscopically proven shift and broadening of water and lipid resonances (1-2 ppm) in this anatomical region. Only patients with SIH showed additional focal enhancement along the spinal nerve roots and/or in the spinal epidural space. In conclusion CE MR myelography with spectral selective fat suppression shows a reproducible cervicothoracic artefact, imitating CSF leakage. Selective water excitation technique as well as periradicular and epidural contrast collections may be helpful to discriminate between real pathological findings and artefacts.

Morphologic Changes of L5 Root at Coronal Source Images of MR Myelography in Cases of Foraminal or Extraforaminal Compression

TWO FINDINGS EASILY FOUND AT CORONAL SOURCE IMAGES OF MR MYELOGRAPHY (MRM) WERE EVALUATED : dorsal root ganglion (DRG) swelling and running course abnormality (RCA) of L5 exiting root at foramen or extraforamen. We tried to find the sensitivity of each finding when root was compressed. From 2004 July to 2006, one hundred and ten patients underwent one side paraspinal decompression for their L5 root foraminal or extraforaminal compression at L5-S1 level. All kinds of conservative treatments failed to improve leg symptom for several months. Before surgery, MRI, CT and MRM were done. Retrospective radiologic analysis for their preoperative MRM coronal source images was done to specify root compression sites and L5 root morphologic changes. DRG swelling was found in 66 (60%) of 110 patients. DRG swelling has statistically valuable meaning in foraminal root compression (chi-square test, p < 0.0001). Seventy-two (66%) in 110 patients showed abnormal alteration of running course. Abnormal running course has statistically valuable meaning in foraminal or extraforaminal root compression (chi-square test, p < 0.0001). Three-dimensional MRM provides precise thin sliced coronal images which are most close to real operative views. DRG swelling and running course abnormality of L5 exiting root are two useful findings in diagnosing L5 root compression at L5-S1 foramen or extraforamen. MRM is thought to provide additional diagnostic accuracy expecially in L5-S1 foraminal and extraforaminal area.

「画像診断の進歩」脊髄の画像診断の進歩

Three decades ago, X-ray was the main procedure for imaging diagnosis. However, it was difficult to diagnose spinal disorders based on X-ray alone because it could not obtain sufficient information from the surrounding bony spinal column. With the advent of magnetic resonance imaging (MRI) and computed tomography (CT), the diagnostic accuracy of spinal disorders has improved significantly regarding their localization and pathological conditions. In this paper, we review the progress in the diagnostic imaging and describe the future prospects. MRI provides a morphological diagnosis based on a range of more invasive to less-invasive techniques, and the production of two-dimensional to three-dimensional images. For example, MR myelography is comparable or superior to conventional myelography and MR cisternography clearly demonstrates the nerves and roots in the spinal canal. In addition, multi-row detector CT (MDCT) systems provide details of bone and soft tissue with multiplanar reconstruction. CT myelography together with MDCT significantly improves image quality and has an advantage for dynamic investigation. CT angiography with 3D reconstruction depicts cervical vascular information. In the near future, functional and metabolic imaging will play an important role in the diagnosis of spinal cord disorders. Duc to the large volume of data obtained with MDCT, it will be necessary to organize the systems for the management of data. To take advantage of these data, it is important to learn about the precise anatomy of the spinal lesion and pathological conditions.

Evaluation of lumbar decompression with pre-operative and post-operative MR myelogram

Magnetic resonance Myelography(MRM) is noninvasive technique that provide anatomical information about subarachnoid space. Objective of this study was to evaluate accuracy of MRM for demonstration of lumbar decompression and its correlation with clinical outcome. 53 patients of prolapsed disc were imaged with MRM postoperatively and evaluated with pre operative MRM and clinical leg pain relief. Diagnostic accuracy of these imagining strategies for lumbar decompression was calculated and correlated with clinical outcome. MRM when employed in routine practice is of limited value, assisting in establishing diagnosis in minority cases (6%). However, MRM adds only short time (8 seconds) to the overall examination and imaging study like this, which includes pre-operative and post-operative evaluation, is more evidence based and scientific. Routine imaging post-operative MRM cut is not expensive. Hence, post-operative MRM ,rather than whole MRI is highly recommended for patients of lumbar decompression and having postoperative persistent symptoms specifically leg pains.

Effect of Magnetic Resonance Myelography on the Target Volume in Craniospinal Irradiation in Children

Aims To examine the potential role of magnetic resonance myelography (MRM) in defining the clinical target volume for the spinal field in craniospinal irradiation in children. Materials and methods Of the 42 patients for whom magnetic resonance imaging (MRI) of the spine was carried out, 12 patients had MRM. The width of the cerebrospinal fluid (CSF) with any lateral extension at different levels was measured from the coronal MRM. The clinical target volume was defined using MRM and the conformal field surface area was compared with the direct conventional field. The inferior border of the thecal sac was determined from MRI spine of 42 patients. Results Coronal MRM showed variation in the width of the CSF at different levels. The maximum width was 2.9 cm (level of C2). In the same case, the width of the CSF at the level of D8 was 1.7 cm. The mean surface area of the conventional field that covered the CSF was 190.6 cm 2, as compared with 150.5 cm 2 using conformal field, with an 18.5% reduction in the irradiated surface area. The thecal sac ended at S2 in 40.4% of the patients, whereas it ended above and below this level in 28.6 and 31%, respectively. Conclusions Implementation of coronal MRM during the treatment planning will improve target definition and lead to a more conformal field. Planning systems with the ability to fuse MRM with reconstructed coronal computed tomography are highly desirable. The use of MRI is highly recommended to individualise the lower border of the spinal field in craniospinal irradiation.

Observer Variability in the Evaluation of Multiple Lumbar Stenosis by Routine MR—Myelography and MRI

Retrospective study. To determine whether magnetic resonance myelography (MRM) improves the evaluation of the severity of stenosis in patients with multilevel lumbar stenosis. MRM shows a similar image as myelography in a noninvasive manner. One hundred patients over 50 years of age with multiple lumbar stenosis who were prospectively referred for MR imaging (MRI) with MRM were enrolled in the study. The most severe stenotic segment and the degree of stenosis of that segment, as assessed by the extent of remaining subarachnoidal space (1: normal to 50%; 2: over 50% but not a total blockage; 3: total blockage) were evaluated in a blinded manner by 2 observers. Conventional MRI (class A), MRM (class B), and MRI combined with MRM (class C) were evaluated independently and interobserver and intraobserver reliability were assessed. In the selection of the most severe segment and degree of stenosis, for both observers, the consensus between class (B) and class (C), was higher than that of class (A) and class (C). The average kappa values for interobserver agreement in the selection of the most severe segment/assessing the degree of stenosis for classes (A), (B), and (C) were 0.649/0.727, 0.782/0.771, and 0.832/0.784, respectively. Intraobserver kappa values were also highest for class (B), followed by class (C), and then class (A). Observations were within the range of "almost perfect" (0.81< or =kappa< or =1), with the exception of the selection of the most severe segment in class (A) by one of the observers. When employed in routine practice, MRM could be of value for improving observer reliability in the assessment of severity of stenosis in multiple lumbar stenosis.