Imaging of spinal trauma

Approximately 2% to 3% of blunt trauma victims suffer injury to the spinal column each year, often with devastating consequences. This article discusses clinical criteria for screening for spinal injury and the increasing roles of multidetector CT and MR imaging in the evaluation of spinal trauma. Both CT and MR imaging safety issues also are addressed. Lastly, the role of imaging in the evaluation of whiplash injury, instability, vascular injury, and delayed traumatic sequelae is discussed.     

Magnetic resonance applications in cerebral injury.

CT and MR imaging are complementary in the evaluation of cerebral head trauma. CT is still more useful for the initial evaluation of the acutely unstable patient who has a head injury. However, many lesions are identified by MR imaging such as cortical contusions, small subdural hematomas, and diffuse axonal injuries that may not be seen on CT examinations. In addition, MR angiography can play an important role in the diagnostic evaluation of the trauma patient. MR angiography can be clinically useful in delineating vascular abnormalities such as arterial occlusions, arteriovenous fistulae, dissecting aneurysms, and venous sinus occlusion. In pediatric trauma, MR imaging appears to be superior to CT in assessing head injuries, particularly those due to child abuse.     

MR imaging in cervical spine trauma

Continual improvements in MR imaging, technology and MR imaging-compatible monitoring and fixation devices have allowed the incorporation of this relatively new imaging modality into standard algorithms for cervical spine trauma assessment. The ability of MR imaging to define the type of spinal cord injury, the cause and severity of spinal cord compression, and the stability of the spinal column is unmatched. The heavy reliance of the spinal surgeon on MR imaging for decisions regarding the type of therapy, the timing, the approach of surgical intervention, and for predicting patient outcome attests to the usefulness of this modality.     

MR imaging of the spinal cord: current status and future advances.

The advent of MR imaging has dramatically altered the evaluation of suspected myelopathy. MR is far less invasive than traditional imaging techniques and often offers a degree of understanding of an abnormality not previously possible. These achievements have closely followed recent technologic advances, such as the development of contrast agents and the introduction of sequences that permit a reduction in both imaging time and artifacts. The current role of MR in the imaging of spinal cord disorders, including intramedullary tumors, infectious and inflammatory myelitis, demyelinating diseases, vascular lesions, trauma, syringomyelia/hydromyelia, and neurodegenerative disorders, is reviewed. While further improvements will undoubtedly occur, the field of spinal MR imaging appears to be entering a maturing phase.     

Spine trauma

Spinal fractures represent 3% to 6% of all skeletal injuries. Spine trauma is a complex diagnostic area in which the radiological assessment is crucial. Plain radiography is often used as the initial diagnostic modality. However, stabilization of the acutely injured spine is a primary concern. In this respect, computed tomography (CT) is vastly superior to plain film in terms of speed and accuracy. In many trauma centers, CT has replaced plain film as the primary modality for evaluation of spinal trauma. Magnetic resonance imaging is not indicated for all cases of spinal trauma but provides detailed information about soft tissue structures including the intervertebral disc, the ligaments, the epidural space, the blood vessels, and the spinal cord. MR imaging provides information on these structures not obtained from other modalities. Patients with spinal cord injury may suffer devastating long-term neurologic deficits, so prompt and efficient spinal imaging guidelines are necessary in all trauma centers.     

Demonstration of diastematomyelia and associated abnormalities with MR imaging

Three patients were studied with a 0.3 T superconducting magnet to assess the role of magnetic resonance (MR) imaging in the recognition and evaluation of diastematomyelia and associated abnormalities. Comparison was made with other imaging techniques, including metrizamide computed tomographic (CT) myelography. With MR imaging, the divided spinal cord was well imaged in its entire craniocaudal extent, comparable to CT myelography. The bony septum, when it contained a marrow cavity, was also seen well. In two patients, dural ectasia and low position of the spinal cord with and without associated lipoma were clearly imaged. MR imaging demonstrated associated syringohydromyelia in one patient that was not detected by other radiologic studies. This preliminary experience with MR imaging of diastematomyelia suggests that once the bony details of the abnormality are defined, MR imaging can delineate the presence and extent of the divided spinal cord as well as its associated abnormalities adequately, obviating other studies.     

The impact of magnetic resonance on the diagnostic evaluation of acute cervicothoracic spinal trauma

From 1984 to 1987 magnetic resonance (MR) imaging was performed on 100 patients suffering acute spinal trauma. MR demonstrated one or more injuries to the cervicothoracic region in 31 patients. It displayed a spectrum of spinal cord injury ranging from mild compression and swelling to complete transection. MR was also useful in evaluating alignment at the cervicothoracic junction, in depicting ligamentous injury, in establishing the presence of disc herniation, and in identifying unsuspected levels of injury. We present a diagnostic algorithm that incorporates the role of MR in evaluating acute cervicothoracic spinal trauma and emphasizes the replacement of myelography by MR in the initial assessment of neurologic deficit.     

Imaging of the spine and spinal cord

Recent technologic advances in MR imaging of the spine and spinal cord have been aimed at shortening examination time and suppressing artifacts. Gradient-recalled fast T2-weighted imaging is advocated for evaluating cervical radiculopathy. Better signal-to-noise ratios are achieved with three-dimensional Fourier transform gradient-recalled T2-weighted imaging and with decreased bandwidth acquisition. Obtaining high-contrast images of the spine is often complicated by the appearance of truncation artifacts. In outpatient radiculography, both iopamidol and iohexol appear safe, but iohexol seems better tolerated. In trauma, MR imaging is definitive, and signal abnormalities can help in evaluating neurologic recovery. Intraoperative spinal sonography may be helpful in evaluating acute injury. Enhancement with gadolinium diethylenetriamine penta-acetic acid is useful in the evaluation of disk space infections, osteomyelitis, and epidural abscess and in the study of spinal cord sarcoidosis. In patients with the acquired immunodeficiency syndrome, MR imaging may show hyperintense spine on T2-weighted images. MR imaging with gadolinium diethylenetriamine penta-acetic acid or gadolinium tetra-azacyclododecane tetra-acetic acid enhancement can be useful in evaluating intramedullary and intradural extramedullary tumors and for determining the extent of spinal leptomeningeal metastases. MR imaging can also be used to differentiate benign from pathologic fractures.     

Imaging of chronic recurrent multifocal osteomyelitis of childhood first presenting with isolated primary spinal involvement

OBJECTIVE: Initial presentation with primary spinal involvement in chronic recurrent multifocal osteomyelitis of childhood (CRMO) is rare. Our objective was to review the imaging appearances of three patients who had CRMO who initially presented with isolated primary spinal involvement. DESIGN AND PATIENTS: The imaging, clinical, laboratory and histology findings of the three patients were retrospectively reviewed. Imaging included seven spinal MR imaging scans, one computed tomography scan, nine bone scans, two tomograms and 16 radiographs. These were reviewed by two musculoskeletal radiologists and a consensus view is reported. All three patients presented with atraumatic spinal pain and had extensive bone spinal pathology. The patients were aged 11, 13 and 12 years. There were two females and one male. RESULTS AND CONCLUSIONS: The initial patient had thoracic T6 and T8 vertebra plana. Bone scan showed additional vertebral body involvement. Follow-up was available over a 3 year period. The second patient had partial collapse of T9 and, 2 years later, of C6. Subsequently extensive multifocal disease ensued and follow-up was available over 8 years. The third patient initially had L3 inferior partial collapse and 1 year later T8 involvement with multifocal disease. Follow-up was available over 3 years. The imaging findings of the three patients include partial and complete vertebra plana with a subchondral line adjacent to endplates associated with bone marrow MR signal alterations. Awareness of the imaging appearances may help the radiologist to include this entity in the differential diagnosis in children who present with spinal pathology and no history of trauma. Histopathological examination excludes tumor and infection but with typical imaging findings may not always be necessary.     

MR imaging in the evaluation of trauma

Although computed tomography (CT) and radiographs are primary modalities in the evaluation of patients undergoing trauma, the indications for magnetic resonance (MR) imaging in trauma have grown. MR has been most useful in patients with central nervous system or musculoskeletal trauma. In head trauma, MRI is most useful in the evaluation of patients with neurologic deficit greater than that expected from CT findings. MRI is useful in such situations because of its improved sensitivity to nonhemorrhagic and microhemorrhagic lesions as well as posterior fossa pathology. In the spine, MRI provides detailed assessment of the disc space, spinal cord, and ligamentous structures; guiding therapeutic decisions; and offering prognostic information. In the musculoskeletal system, MRI offers a noninvasive means of imaging injuries to the muscles, tendons, ligaments, and cartilage of the knee, shoulder, ankle, and elbow. Additionally, MRI may define a subset of radiographically occult bony injuries.     

Imaging of disorders of the spine

Although many papers were published during the past year on disorders of the spine, in this review, papers were chosen and grouped under five broad headings: 1) spinal trauma, 2) disk disease, 3) neoplastic disease, 4) spinal arthritis, and 5) other studies of interest. Although some of the articles chosen for review dealt with conventional radiography, the majority were on applications of CT and MR imaging to conditions affecting the spine.     

Trauma der Wirbelsäule: erste Hilfe durch Schnittbildverfahren

The diagnosis of the traumatized spine is one of the key issues for trauma radiologists. The cross-sectional imaging procedures, computed tomography (CT) and magnetic resonance imaging (MRI) are the essential methods in spinal trauma radiology. These modalities are of great help in accurately assessing injury patterns and extent and in providing indications of patient outcome. In contrast to cross-sectional imaging, radiography has a role in the evaluation of minor spinal trauma only. It is generally accepted that trauma radiologists do not use typical classifications to evaluate the spine partly because such an ideal classification system does not yet exist. Not least because of this classification difficulty, eponyms and synonyms are widely used to describe traumatology of the spine as a high level of specific information is included in these various terms. The members of the trauma team should be aware of the strengths and limitations of the methods used in the assessment of the spine. This article provides a brief outline of fundamental knowledge about the diagnosis of spinal trauma.     

Magnetic resonance imaging evaluation of acute spine trauma

A comparison study of magnetic resonance imaging (MR), computed tomography (CT), and plain film evaluation of 113 consecutive spine trauma cases was conducted. The rate of true-positive findings (sensitivity) on MR was shown to be significantly higher than for CT or plain films in the evaluation of soft tissue or ligamentous injury (P<0.001). MR had a significantly lower rate of positive findings for fracture than CT (P<0.001) and was also shown to be significantly less sensitive for fracture than plain films (P<0.001). Spinal cord contusion, epidural hematoma, high-grade stenosis, and ligamentous or soft tissue injury were best evaluated with MR. MR, CT, and plain films are all important modalities for the evaluation of acute spine trauma. It is recommended that, after clinical examination, patients with spine trauma be evaluated first by plain film. If there is clinical or radiologic suspicion for acute spine injury, MR should be the next diagnostic procedure performed. If MR is positive for acute injury, CT may be indicated. CT best defines the extent of bony injury, and MR the extent of soft tissue injury, intrinsic spinal cord pathology, and extrinsic dural sac compression.     

Correlation of MR imaging findings with intraoperative findings after cervical spine trauma

BACKGROUND AND PURPOSE: There are limited data correlating MR imaging and anatomic findings of ligamentous injury in cervical spine trauma. This study compares acute MR imaging with surgical observations of disk/ligamentous injury after blunt cervical trauma. MATERIALS AND METHODS: Consecutive patients with acute cervical spine trauma who underwent preoperative MR imaging and surgery from 1998 to 2001 were identified. MR imaging was obtained within 48 hours of injury for most patients. All scans included sagittal T1, T2 fat-saturated, and short tau inversion recovery sequences. At surgery, extent of injury at the operated level was recorded on a standardized form for either anterior or posterior structures or both depending upon the operative approach. MR examinations were separately evaluated by 2 readers blinded to the intraoperative findings. Radiologic and surgical findings were then correlated. RESULTS: Of 31 patients, an anterior surgical approach was chosen in 17 patients and a posterior approach in 13 patients. In one patient anterior and posterior approaches were utilized. Seventy-one percent of patients had spinal cord injury on MR imaging. MR imaging was highly sensitive for injury to disk (93%), posterior longitudinal ligament (93%), and interspinous soft tissues (100%), but it was less sensitive for injury to the anterior longitudinal ligament (71%) and ligamentum flavum (67%). For most ligamentous structures, there was limited agreement between specific MR imaging findings and injury at surgery. CONCLUSION: In acute cervical spine trauma, MR imaging has moderate to high sensitivity for injury to specific ligamentous structures but limited agreement between specific MR imaging findings and injury at surgery. MR imaging may overestimate the extent of disruptive injury when compared with intraoperative findings, with potential clinical consequences.     

Cervical stenosis, spondylosis, and herniated disc disease

While IntCECT is still considered by many to be the optimal modality in cervical spine imaging, it is the most invasive of the techniques considered here. MR imaging may have nearly equivalent diagnostic capability in many cases of degenerative disc and spine disease. The value of unenhanced CT essentially is limited to the demonstration of bony changes. In the evaluation of radiculopathy, either MR imaging or IvCECT is useful for the initial screening and may be the only study needed. MR imaging is the study of choice for diseases of the spinal cord. With continuing progress in MR capability, IntCECT is shifting more toward a supplemental or confirmatory role. A rigid neurodiagnostic algorithm for this common radiologic problem is not possible. Rather, each step of the diagnostic process is influenced by the individual patient. Specific patient characteristics may affect the selection of an imaging modality. Modification of routine studies, such as use of gadolinium or oblique MR imaging, may be indicated in some patients. Finally, because of the high prevalence of asymptomatic disc and spine changes, knowledge of clinical findings is essential in the accurate interpretation of anatomic findings.     

Magnetic resonance imaging of spinal dysraphism

MR imaging has become the definitive diagnostic procedure for the evaluation of suspected spinal dysrhaphic processes. Techniques for spinal MR imaging are discussed and MR findings in patients with surgically verified dysrhaphic spinal lesions are reviewed.     

Imaging of musculoskeletal trauma

Many significant papers in the current literature on musculoskeletal trauma deal with new advances in MR imaging. The increasing role of MR imaging in the evaluation of traumatic lesions of the knee explains the number of papers dealing with the differentiation of true traumatic lesions from normal variants or clinically insignificant changes. Other contributions on musculoskeletal trauma deal with more conventional imaging techniques, such as arthrography, plain films, and even complex tomography.     

Contrast-enhanced MR imaging in the evaluation of treatment response and prediction of outcome in multiple sclerosis

MR imaging is becoming increasingly important in the evaluation of multiple sclerosis based on its sensitivity to acute, often subclinical events in the brain and because it provides a basis for measuring the accumulation of disease over time. Contrast-enhanced MR imaging in particular evaluates disease at the fundamental level of events affecting the blood-brain barrier. This review emphasizes (a) recent developments in the use of contrast-enhanced MR imaging as a measure of disease in patient groups and individuals and (b) its emerging role in evaluating new therapies.     

Prediction of neurologic outcome in acute spinal cord injury: the role of CT and MR.

PURPOSE: 1) To determine whether MR appearances of the spinal cord in acute trauma correlate with clinical prognosis, and 2) to identify other MR and CT prognostic factors in acute spinal trauma. METHODS: Retrospective evaluation of MR, CT, and clinical examinations in 32 acute spinal trauma patients examined between 1987 and 1990. RESULTS: All 21 patients with abnormal spinal cords on MR had complete motor paralysis at presentation, compared to only three of 11 patients with normal cords. Whereas cord transection and hemorrhagic contusion had poor prognoses, 73% of patients with cord edema and 100% of patients with normal cord had useful motor function at outcome. At follow-up MR, areas of cord contusion developed into cysts, while edema resolved, leaving residual areas of myelomalacia. Associated spinal fractures, ligament injury, and cord compression were associated (P < .05) with a worse prognosis. Spondylotic changes were a significant risk factor for spinal cord injury, mediated by cord compression. CONCLUSIONS: MR and CT are valuable techniques for quantifying injury and predicting prognosis in acute spinal trauma.     

A comparison between M.R.I. and C.T. in the investigation of neurological deterioration in longstanding spinal trauma.

MRI at 0.3T and CT with myelographic contrast (CTM) were compared in the retrospective evaluation of 35 patients investigated for the development of new neurological symptoms following longstanding spinal cord injury. Compared with MRI, CTM was relatively accurate for the demonstration of spinal cord compression, but failed to identify 23% of patients with spinal cord atrophy, and 43% of patients with post-traumatic syrinx formation. However, 5 patients had unsatisfactory MR imaging, either due to motion or metallic artifact, and in 3 of these, CTM demonstrated a syrinx. Although MRI is the method of choice in the investigation of this problem, CTM may still be required for patients with an unsatisfactory MR examination. Magnetic Resonance (MR) imaging is now an established technique for imaging the spine, with accurate depiction of the spinal cord, as well as the adjacent soft tissues (1, 2). However, the cost of this technique, and its as yet limited availability in Australasia, has resulted in the necessity to demonstrate its superiority over other imaging modalities for any specific clinical problem (3). One of the major areas of impact of MR has been in the investigation of the problem of acute neurological deterioration in patients with past spinal trauma (4, 5, 6). Some of these patients will have treatable causes of deterioration, either a post-traumatic syrinx, or spinal cord compression (6), and MR can be used to image these conditions (7), which, until recently, were investigated with computed tomography with myelographic contrast medium (CTM), (8, 9).(ABSTRACT TRUNCATED AT 250 WORDS)