胸腰椎外伤后脊髓损伤CT平扫的局限性

目的：探讨CT平扫诊断胸腰椎外伤后脊髓损伤的局限性。方法：收集近7a来48例胸腰椎外伤的CT平扫结果、X线片结果及临床资料，并进行对比分析。结果：48例胸腰椎外伤病人中椎体骨折73个，单发59个，多发14个，其中CT示碎骨入椎管内的有25处，血肿1处，附件骨折36处，X线片漏报附件骨折16处(44％)瘫痪病人11例，均经手术治疗，术中发现椎管内碎骨15处，血肿2处，脊髓挫伤或断裂10处。结论：CT平扫对椎体、附件骨折、椎管形态改变和碎骨片移位及明显的椎管内血肿的诊断，优于X线平片，但是对脊髓损伤的显示有局限性，建议胸腰椎外伤后瘫痪病人做脊髓造影(CTM)或磁共振成像(MRI)。     

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.     

Surface coil MR of spinal trauma: preliminary experience

Nineteen fractured vertebral bodies involving the spine from C1 to L2 in 14 patients were imaged with a 0.6-T magnet using prototypical surface coils. Ten of these patients were studied within the first week of trauma. CT and plain films are superior to MR in detecting fractures and identifying the origin of displaced fragments in cases of extensive comminution. However, all body fractures and most posterior element fractures in the thoracolumbar spine were visible on MR. Fractures involving the cervical neural arch were difficult to detect on transverse section without CT correlation. Our results indicate that MR can probably replace CT in the thoracolumbar region. MR is superior to CT in demonstrating ligamentous injury and trauma to the disk. Unlike CT, MR shows the relation of the thecal sac and spinal cord to retropulsed fragments and epidural hematoma. MR also visualizes cord parenchyma; two cases of cord hemorrhage were not seen on CT. Even at this early stage of development, surface coil MR promises to become important in the evaluation of spinal trauma, not only in assessing the integrity of the spinal canal and cord, but in separating stable from unstable fractures on the basis of disruption of the posterior ligaments and elements. Additionally, the demonstration of rupture of specific ligaments may have an impact on surgical management.     

Should an MR scan be performed routinely after a normal clearance CT scan in the trauma patient? Experience with 59 cases

Magnetic resonance (MR) imaging is not routinely used to exclude ligamentous and other soft tissue injury in the unconscious trauma patient. In order to determine the frequency and types of soft tissue injuries detected by MR imaging but not by computed tomography (CT), we performed a retrospective investigation comparing the MR findings in 59 trauma patients, either alert or unconscious, who previously had undergone a negative clearance multislice CT study of the cervical spine. Six patients had abnormalities not identified on the CT studies, including four cases of ligamentous injury.     

MR imaging of traumatic spinal injuries

Plain films form the initial evaluation in all cases of spinal trauma. In cases of indeterminate or incomplete plain radiographs, further evaluation should be performed by multiplanar computed tomography (CT) and/or magnetic resonance imaging (MRI). Rapid triage is important to distinguish surgical and nonsurgical cases, as this has implications in terms of relief of cord compression and long-term prognosis. CT is unparalleled in its capacity to demonstrate bony abnormalities. MRI is the modality of choice in the evaluation of soft tissue injuries, in particular where there is a suspicion of ligamentous or intervertebral disc injury and spinal cord injury. MRI has the ability to distinguish between spinal cord edema and hemorrhage, which has important prognostic significance.     

CT in the evaluation of spine trauma

Fifteen patients admitted for spine trauma in an 8 month period were studied with computed tomography (CT). All the patients had initial routine plain film screening, and 10 of 15 were also examined with conventional tomography. Five patients sustained vertical fall, axial-load injuries in the thoracolumbar junction region; two others suffered missile injury to the spine. CT provided more information than plain films in all these patients due to its superior imaging of bony detail and its ability to assess soft-tissue damage. In four of these patients, conventional tomography was done but contributed no additional information. Eight other patients sustained complex fractures of the cervical spine. In all but one, the combination of plain films and CT allowed complete evaluation of the injury. In one patient, conventional tomography showed an additional linear fracture one vertebral level below the main region of injury. Plain films and CT allow complete, safe, rapid, easily interpretable evaluation of spine trauma patients in the acute setting. Conventional tomography yields no additional clinically vital information in the acute evaluation of spine trauma, when plain films are abnormal. Its current ability to show finer bony detail than CT can be reserved for evaluating equivocal plain film and CT findings or more complete evaluation (if indicated) after the patient is clinically stable.     

Can chest and abdominal trauma CT eliminate the need for plain films of the spine? – Experience with 329 multiple trauma patients

Purpose: To compare the accuracy of spine plain films with chest and abdominal trauma CT in detection of spine fractures. Methods: The study prospectively enrolled 329 multiple trauma patients. Of these, 38 patients had both chest CT for trauma and thoracic spine plain films, and 87 patients had both abdominal CT for trauma and lumbar spine plain films. Results: Of the fractures visible at either chest trauma CT or thoracic spine plain film examination, all were diagnosed on CT and 62 % on plain films. Of fractures visible at either abdominal trauma CT or lumbar spine plain films, 94 % were diagnosed on CT and 67 % on plain films. The one false negative CT involved an articular process fracture, which was visible but not mentioned, in a patient with a sacral fracture. Conclusion: Evaluation of the digital scout images and bone windows when a patient has chest and abdominal trauma CT appears to be as accurate as thoracic and lumbar spine plain films in the evaluation of spinal trauma.     

Exclusion of unstable cervical spine injury in obtunded patients with blunt trauma: is MR imaging needed when multi-detector row CT findings are normal?

PURPOSE: To retrospectively determine what information, if any, magnetic resonance (MR) imaging of the cervical spine in obtunded and/or "unreliable" patients with blunt trauma adds to multi-detector row computed tomography (CT) of the entire cervical spine (including routine multiplanar sagittal and coronal reformations) when the CT findings are normal. MATERIALS AND METHODS: The study was HIPAA compliant and institutional review board approved. Informed consent was not required. From April 2001 to November 2003, 1400 trauma patients underwent MR imaging of the cervical spine to evaluate potential cervical spine injuries. Multi-detector row CT of the cervical spine was performed with a four- or 16-detector row scanner. MR imaging of the cervical spine was performed with transverse gradient-echo, sagittal intermediate-weighted, sagittal short inversion time inversion-recovery, and sagittal T1- and T2-weighted fast spin-echo sequences. Many MR examinations were performed to exclude soft-tissue injuries in the cervical spine of obtunded patients with blunt trauma in whom cervical spine injury could not be excluded with physical examination. Complete cervical spine MR studies were obtained to evaluate soft-tissue injuries in 366 obtunded patients with blunt trauma (281 male and 85 female patients; age range, 13-92 years; mean age, 42.1 years). The patients had previously undergone total cervical spine multi-detector row CT with normal findings. The results obtained with these two modalities were compared. RESULTS: MR images were negative for acute injury in 354 of the 366 patients and negative for cervical spine ligamentous injury in 362. Seven of the 366 patients had cervical cord contusions, four patients had ligamentous injuries, three patients had intervertebral disk edema, and one patient had a cord contusion, a ligamentous injury, and an intervertebral disk injury. Four patients had ligamentous injuries; however, all of these patients had ligament injuries limited to only one of the three columns of cervical spine ligament support. Multi-detector row CT had negative predictive values of 98.9% (362 of 366 patients) for ligament injury and 100% (366 of 366 patients) for unstable cervical spine injury. CONCLUSION: A normal multi-detector row CT scan of the total cervical spine in obtunded and/or "unreliable" patients with blunt trauma enabled the authors to exclude unstable injuries on the basis of findings at follow-up cervical spine MR imaging.     

急性颈椎外伤的MRI诊断

目的 分析急性颈椎外伤的MRI征象,评价MRI在急性颈椎外伤诊断中的价值及限度。方法收集急性颈椎外伤150例,均有MRI检查和X线平片,15例有CT片,采用14个参数进行分析记录。结果150例中MRI检出骨折51个,小关节脱位30个,椎体脱位35个;外伤性椎间盘突出40个,硬膜外血肿2例;脊髓损伤69例;脊髓受压迫20例;前、后纵韧带损伤21例;棘间韧带和黄韧带损伤15例;椎前血肿或水肿30例;椎旁和背侧软组织损伤40例;X线平片发现椎体骨折55个,椎体脱位35个;小关节脱位35例,附件骨折25个,椎前软组织肿胀20例。15例CT均发现骨折,小关节脱位,椎管狭窄。结论MRI在显示脊髓、韧带、椎间盘和软组织损伤方面优于CT和X线平片。MRI能全面反映颈椎各种损伤的病理特征,为评估颈椎稳定性提供充分的依据;MRI和X线片的骨折检出率没有明显差异,CT应该用于复杂的颈椎骨折检查。     

MR imaging of acute cervical spinal ligamentous and soft tissue trauma

The increasing availability of magnetic resonance imaging (MRI) and the high sensitivity of MRI for soft tissue injury are resulting in the increased use of MRI for the evaluation of acute trauma. As cervical spine injury can have a devastating consequence, MRI is being more commonly used to evaluate cervical spine injury in the acute setting, necessitating emergent interpretation by the on-call radiologist. Unless one is formally trained in a trauma center, the MRI findings of soft tissue and ligamentous cervical spine injury may not be fully appreciated. The goal of this pictorial review is to familiarize the reader with some of the more common soft tissue, vascular, and ligamentous injuries seen on MRI of the cervical spine in the emergent setting.     

Trauma to the foot

Minor trauma to the foot may cause stress fracture, avulsion fracture or ligamentous and tendon injury. Plain radiographs are frequently normal. Radionuclide bone scan is a sensitive detector of early bone injury. A stress fracture may develop focal uptake or diffuse uptake throughout the bone involved. MR imaging is the most sensitive means of evaluating injury to the soft tissues. Acute edema, partial tear, complete tear, and chronic tendinitis have distinct features on T1- and T2-weighted images. Major trauma occurs most commonly as a result of falls from heights and from motor-vehicle accidents. Plain films are useful in the initial evaluation of the extent of trauma. CT is particularly useful in evaluating calcaneal fractures that involve the subtalar joint. Both MR imaging and CT scans are useful in detecting injured or entrapped tendons associated with fracture-dislocations.     

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.     

急性脊柱创伤的影像学分析

目的 :探讨各种影像检查对急性脊柱创伤的诊断价值及限度。方法 :回顾性分析 2 5 2例急性脊柱创伤病例 ,均在伤后 48h内行X线平片、CT及MRI检查。结果 :共检出椎体骨折 2 78例 ,X线平片、CT及MRI检出率相同 ,三者对附件骨折的检出率分别为 9.1%、2 3 .4%、14 .3 %,差异有极显著性意义 (P <0 .0 1)。 15 2例MRI直接显示脊髓损伤。结论 :在急性脊柱创伤的影像诊断中 ,X线平片可作初检手段 ,CT对骨折检出率最高 ,MRI对脊髓损伤诊断最佳 ,三者结合可提高诊断水平。     

MR imaging of the spine: trauma and degenerative disease

The purpose of this paper is to discuss the capabilities and drawbacks of MR imaging in patients with trauma to the spine and degenerative spinal conditions. In spinal trauma MR imaging is secondary to plain X-ray films and CT because of the greater availability and ease of performance of these techniques and their superior capability for detecting vertebral fractures. Magnetic resonance imaging is useful for detecting ligamentous ruptures and intraspinal mass lesions such as hematoma, and for assessing the state of the spinal cord and prognosis of a cord injury. In degenerative spinal disease the necessity is emphasized of critically evaluating the clinical relevance of any abnormal feature detected, as findings of degenerative pathology are common in individuals without symptoms. Magnetic resonance myelography permits rapid and accurate assessment of the state of the lumbar nerve roots (compressed or not). In the cervical region the quality of the myelographic picture is often degraded in patients with a narrow spinal canal.     

Acute cervical spine trauma: evaluation with 1.5-T MR imaging

Twenty-one patients with acute neurologic deficits following cervical spine trauma were evaluated with magnetic resonance (MR) imaging (n = 21), computed tomography enhanced with intrathecal contrast material (CT myelography) (n = 18), myelography (n = 13), cervical spine radiography (n = 21), and intraoperative sonography (n = 7). MR imaging proved superior to other modalities in demonstrating parenchymal spinal cord injuries and cervical intervertebral disk herniation. Although both T1- and T2-weighted studies appear necessary to evaluate the anatomic relationship of the spinal cord, thecal space, intervertebral disks, and surrounding osseous and ligamentous structures, T2-weighted sequences were more sensitive than T1-weighted studies for detection of spinal cord injury. CT myelography was superior to MR imaging in demonstrating cervical spine fractures. In most cases, myelography revealed no information that was not apparent from both CT and MR imaging studies. Preliminary experience with MR imaging of acute cervical spine trauma suggests that it should be the study of choice in symptomatic patients who are otherwise clinically stable. CT may still be required in selected patients to evaluate complex fractures.     

膝关节组成结构细微损伤的影像学研究

目的 探讨X线平片、CT和超低场MR在膝关节细微损伤诊断中的临床价值。方法 回顾性分析16例经临床证实的膝关节细微损伤患者的X线平片，CT和MRI资料。结果 16例，左侧6例，右侧10例;X线检出5处髁间突骨折，1处可疑胫骨平台骨折;CT检出12处微骨折，4处髁间突骨折;MR检出25处骨挫伤，9处微骨折。结论 在外伤后膝关节细微损伤的检查中，超低场MR是一种较佳的检查方法;X线平片是最基本的检查方法，明确诊断应结合MR检查。CT可以作为评价膝关节细微损伤的一种补充方法，但不应作为常规检查。     

Evaluation of acute cervical spine imaging based on ACR Appropriateness Criteria?

The objectives of this study were to determine the rate of acute blunt cervical spine injury at an academic urban level 1 trauma center and to evaluate the utilization of cervical spine imaging based on the established American College of Radiology (ACR) Appropriateness Criteria?. We retrospectively reviewed all radiography and CT imaging of the cervical spine performed over a year period in adult patients presenting with acute blunt cervical spine trauma. Exclusion criteria were children ≤17 years, non-acute trauma of ≥72 h, and penetrating trauma. Any fracture, dislocation, or ligamentous instability demonstrated by diagnostic imaging and requiring stabilization or specialized follow-up was defined as clinically significant cervical spine injury. A total of 1,325 cervical spine studies were reviewed in 1,245 patients; 32.7% (433/1,325) were cervical spine radiographs and 67.3% (892/1,325) were CT examinations. Approximately 1.5% (19/1,245) of the patients demonstrated clinically significant acute cervical spine injury. There were 6.4% (80/1,245) patients who received both cervical spine radiographs and CT as imaging evaluation. Based on the ACR Appropriateness Criteria?, all of the cervical spine radiographs performed (433) were determined to be “inappropriate” imaging in the setting of acute cervical spine injury.     

Blinded comparison of cranial CT and MR in closed head injury evaluation.

PURPOSETo compare CT and MR in the evaluation of acute head injury.METHODSOne hundred seven consecutive patients who were referred to the emergency department and underwent both MR and CT cranial examinations within 48 hours were retrospectively reviewed. The films were interpreted by two neuroradiologists blinded to all patient information.RESULTSThe sensitivity of MR was significantly higher than that of CT for the detection of contusion, shearing injury, subdural and epidural hematoma, and sinus involvement. The sensitivity of CT was significantly higher than that of MR for the evaluation of fracture. The sensitivities of MR and CT were statistically equivalent for the detection of superficial soft-tissue injury. The overall sensitivity of MR for the detection of abnormalities in acute head trauma was 96.4%, and for CT was 63.4%.CONCLUSIONSCT and MR are complementary studies in the evaluation of acute head trauma. MR is necessary to define or exclude contusions, deep shearing injury, and extraaxial fluid collections in acute head trauma.     

MR Imaging of the Cervical Spine in Nonaccidental Trauma: A Tertiary Institution Experience

BACKGROUND AND PURPOSE:Cervical MR imaging has demonstrated a utility for detecting soft tissue injury in nonaccidental trauma. The purpose of this study was to identify the incidence and types of cervical spine injury on MR imaging in nonaccidental trauma and to correlate cervical spine injury with parenchymal injury on brain MR imaging and findings on head CT.MATERIALS AND METHODS:A retrospective review of children diagnosed with nonaccidental trauma in a tertiary referral pediatric hospital over 8 years was performed. Inclusion criteria were children younger than 5 years of age, a confirmed diagnosis of nonaccidental trauma, and cervical spine MR imaging within 1 week of presentation. Brain and cervical spine MR imaging, head CT, cervical radiographs, and skeletal surveys were reviewed.RESULTS:There were 89 patients included in this study (48 males; mean age, 9.1 months [range, 1–59 months]). Cervical spine injury on MR imaging was found in 61 patients (69%). Ligamentous injury was seen in 60 patients (67%), with interspinous ligaments being most commonly involved. Abnormal capsular fluid (atlanto-occipital and atlantoaxial) was present in 28 patients (32%). Cervical spine injury on MR imaging was significantly associated with parenchymal restricted diffusion on brain MR imaging and parenchymal injury on head CT (P = .0004 and P = .0104, respectively). Children with restricted diffusion on brain MR imaging were 6.22 (point estimate) times more likely to have cervical spine injury on MR imaging.CONCLUSIONS:There is a high incidence of cervical spine injury in pediatric nonaccidental trauma. Positive findings may affect management and suggest a traumatic etiology.

Cervical spine injury (CSI) is uncommon in children, accounting for only 1–2% of pediatric trauma.¹ There is a higher prevalence of upper cervical injury in infants and toddlers, secondary to mechanism of injury and physiologic immaturity. Younger children are also more likely to have a ligamentous injury than fractures.² A high clinical suspicion and the appropriate use of imaging are the key factors in identifying CSI. Ligamentous injury to the cervical spine is a well-recognized but likely underdocumented condition in pediatric cervical spine trauma, especially when accompanied by complex coexistent injuries or a delay in clinical symptoms.³Recent literature suggests ligamentous injury documented on cervical MR imaging is commonly found in children with abusive head trauma (AHT).^4,5 Spinal injuries in AHT described in various studies include compression fractures, ligamentous injury, cord injury, and subdural hematoma.^6–9 The ligamentous injury is believed to be secondary to a hyperflexion/hyperextension mechanism of injury, and the younger the child, the more likely the upper cervical spine is at risk for injury. The infant or young child''s physical features increase the risk of ligamentous CSI because of the presence of a relatively large head size, ligamentous laxity, and poorly developed paraspinal musculature.^1,2 The incidence of CSI is likely underestimated because cervical MR imaging is not generally part of the routine evaluation of nonaccidental trauma (NAT) with or without evidence of AHT. This is frequently secondary to the absence of abnormalities on radiographs that are part of the routine NAT evaluation. The lack of clinical suspicion of CSI, along with coexistent head injuries, increases the risk of masking the clinical detection of CSI.The purpose of our study was to identify the incidence and types of CSI on MR imaging in a cohort of pediatric patients diagnosed with NAT with or without AHT and to correlate CSI with parenchymal injury on brain MR imaging and findings on head CT.     

Occipital condyle fractures diagnosed by high-definition CT and coronal reconstructions

We describe four cases of fracture of the occipital condyle. In all cases plain cervical spine films were normal. The fracture was diagnosed on the lowest section of a routine CT examination of the head. Further detail was then obtained with high-definition CT and coronal reconstructions. All the patients were found to have a small atlantooccipital subluxation, no greater than 11 mm. Classification and treatment of these fractures is discussed. It is stressed that the lowermost section of a CT head study for cerebral trauma should include the inferior margin of the foramen magnum and that both bone and soft tissue images should be obtained.