CT imaging of blunt traumatic bowel and mesenteric injuries

Delayed diagnosis of a bowel or mesenteric injury resulting in hollow viscus perforation leads to significant morbidity and mortality from hemorrhage, peritonitis, or abdominal sepsis. The timely diagnosis of bowel and mesenteric injuries requiring operative repair depends almost exclusively on their early detection by the radiologist on computed tomography examination, because the clinical signs and symptoms of these injuries are not specific and usually develop late. Therefore, the radiologist must be familiar with the often-subtle imaging findings of bowel and mesenteric injury that will allow for appropriate triage of a patient who has sustained blunt trauma to the abdomen or pelvis.     

闭合性肝脾损伤非手术治疗36例分析

探讨闭合性肝脾损伤非手术治疗的可行性及其效果。认为针对不同伤情、有选择地对肝脾损伤患者行非手术治疗是可行。     

Nonsurgical management of blunt splenic injury: use of CT criteria to select patients for splenic arteriography and potential endovascular therapy

PURPOSE: To determine if contrast material-enhanced spiral computed tomography (CT) can be used to select patients with blunt splenic injuries to undergo arteriographic embolization. MATERIALS AND METHODS: During a 15-month period, 78 patients who were hemodynamically stable and required no immediate surgery underwent contrast-enhanced spiral CT followed by splenic arteriography. CT scans were assessed for splenic vascular contrast material extravasation or posttraumatic splenic vascular lesions. Medical records were reviewed for splenic arteriographic results and clinical outcome. RESULTS: There were 25 grade I, 12 grade II, 27 grade III, 12 grade IV, and two grade V splenic injuries. CT showed active contrast material extravasation in seven patients and splenic vascular lesions in 19 patients. At CT, splenic vascular contrast material extravasation was 100% (seven of seven patients) and a posttraumatic splenic vascular lesion was 83% (10 of 12 patients) sensitive on the basis of arteriographic or surgical outcome in predicting the need for transcatheter embolization or splenic surgery. Overall, CT had a sensitivity of 81% (17 of 21 patients), a specificity of 84% (48 of 57 patients), negative and positive predictive values of 92% (48 of 52 patients) and 65% (17 of 26 patients), respectively, and an accuracy of 83% (65 of 78 patients) in predicting the need for splenic injury treatment. CONCLUSION: Contrast-enhanced spiral CT plays a valuable role in selecting hemodynamically stable patients with splenic vascular injury who may be treated with transcatheter therapy and potentially improves the success rate of nonsurgical management.     

Multidetector CT of blunt traumatic venous injuries in the chest, abdomen, and pelvis

Venous injuries as a result of blunt trauma are rare. Even though current protocols for multidetector computed tomography (CT) of patients with trauma are designed to evaluate primarily the solid organs and arteries, blunt venous injuries may nevertheless be identified, or at least suspected, on the basis of the multidetector CT findings. Venous injuries are associated with high morbidity and mortality rates. Diagnosis of a possible venous injury is crucial because the physical findings of a venous injury are nonspecific and may be absent. This article aims to make the radiologist aware of various venous injuries caused by blunt trauma and to provide helpful hints to aid in the identification of venous injuries. Multidetector CT technology, in combination with interactive manipulation of the raw dataset, can be useful in the creation of multiplanar reconstructed images and in the identification of a venous injury caused by blunt trauma. Familiarity with direct and indirect signs of venous injuries, as well as with examples of blunt traumatic venous injuries in the chest, abdomen, and pelvis, will help in the diagnosis of these injuries.     

Assessment of Pediatric Neurotrauma Imaging Appropriateness at a Level I Pediatric Trauma Center

PurposeThe aim of this study was to assess the prevalence of appropriate neuroimaging on the basis of the ACR Appropriateness Criteria among pediatric patients presenting after head trauma to a level I emergency department.MethodsA retrospective emergency department record review was performed for patients <18 years of age undergoing head CT or MRI for the indication “head trauma” between January 2013 and December 2014. Clinical history and symptoms were compared with the ACR Appropriateness Criteria; the indication was deemed appropriate for ratings of ≥7. Patients were analyzed by age, gender, presentation, imaging obtained, follow-up, treatment, and outcomes.ResultsAmong 207 patients, 120 (58%) were imaged with CT and 107 (52%) with MRI; 20 patients underwent both CT and MRI. One hundred eighty-seven patients (90.3%) were appropriately imaged, with 90.0% of CT studies (108 of 120) deemed appropriate and 91.6% of MRI studies (98 of 107) deemed appropriate. Younger patients were more likely to be inappropriately imaged with CT or MRI than older patients (P = .02 and P < .01, respectively). Patients undergoing CT were older (mean age 9.9 ± 5.8 years) and more likely to be male (85.2%) than those undergoing MRI (5.6 ± 5.6 years and 55.1%, respectively) (P < .01 and P < .001, respectively). The diagnostic yield of positive imaging findings for intracranial trauma was significantly lower in the MRI group (P < .01), and patients undergoing MRI were significantly more likely to return to baseline with conservative management (P < .01).ConclusionsMost pediatric patients undergoing neuroimaging for head trauma did so appropriately per ACR guidelines and had symptom resolution with conservative management. The minority not imaged appropriately represent a target for quality improvement efforts.     

Screening US and CT for blunt abdominal trauma: a retrospective study

OBJECTIVE: To assess the accuracy of screening US and CT in patients with blunt abdominal trauma admitted to the trauma centre of our General Hospital. MATERIALS AND METHOD: The abdominal US reports of 864 primary trauma patients (139 with major and 725 with minor injuries) and 162 CT reports of a subgroup of the same subjects (64 with major and 98 with minor injuries) were reviewed and compared to the best available reference standard. The accuracy of screening US was assessed by evaluating its overall ability to distinguish negative from positive cases by showing at least one of the lesions documented by the reference standard and its specific ability to depict all lesions; CT reports were evaluated only for the method's performance in depicting all lesions. RESULTS: Screening US exhibited a satisfactory overall ability to distinguish negative from positive patients (91.5% sensitivity and 97.5% specificity in major trauma patients versus 73.3% sensitivity and 98.1% specificity in the minor trauma group) and a satisfactory specific ability to depict all injuries in major trauma patients. In minor trauma cases sensitivity was satisfactory for free fluid but unsatisfactory for organ injuries. Of the 21/864 false negative reports (5 in patients with major and 16 in cases with minor traumas), only one affected patient management, a major trauma case, by delaying an emergency laparotomy. The performance of CT in detecting each single lesion was predictably excellent in both patient groups. CONCLUSION: Its satisfactory accuracy for major trauma suggests that US could be employed not only to screen cases for emergency laparotomy but also as an alternative to CT. However, since major traumatic injuries generally carry an imperative indication for CT, especially as regards neurological, thoracic and skeletal evaluation, US should be employed to perform a prompt preliminary examination using a simplified technique in the emergency room simultaneously with resuscitation.     

The spectrum of traumatic injuries at the craniocervical junction: a review of imaging findings and management

The craniocervical junction is an area with unique biomechanical properties and injuries conferred often represent high-impact trauma. The vital structures traversing this region are susceptible to injury with frequent, only subtle findings identified on unenhanced CT, with MRI and CT angiography often revealing the full extent of injuries. This article reviews the osseous and ligamentous anatomy of the region and common injury patterns. Endovascular and neurosurgical management will also be discussed.     

钝性腹部空腔脏器及肠系膜损伤的 CT 诊断

目的：通过对照分析腹部钝性空腔脏器及肠系膜损伤患者术中发现及术前CT征象,寻找判断空腔脏器及肠系膜损伤的特征性CT表现,以助于提高诊断率。方法回顾性分析2011～2013年我院100例钝性腹部创伤患者,其中男性82例,女性18例;年龄11个月～77岁,平均37岁。将其分为A、B两组,A组为经手术证实的有钝性肠道及肠系膜损伤患者（50例）,B组为经手术证实的只有钝性实质性脏器损伤而没有空腔脏器及肠系膜损伤患者（50例）,分析两组中与空腔脏器及肠系膜损伤相关的CT征象,采用单因素分析方法,进一步得出有助于判断是否有空腔脏器及肠系膜损伤的CT征象。结果通过分析发现具有统计学意义的征象有：腹腔或腹膜后积气（P＜0.01,敏感度50％,特异度98％）,肠管壁增厚（P＜0.01,敏感度40％,特异度98％）,系膜增厚（P＜0.01,敏感度42％,特异度88％）,系膜密度增高（P＜0.05,敏感度16％,特异度98％）,腹腔脂肪间隙密度增高模糊（P＜0.05,敏感度18％,特异度96％）,腹膜增厚（P＜0.05,敏感度26％,特异度90％）。结论通过分析发现腹腔或腹膜后积气、肠管壁增厚、系膜增厚、系膜密度增高、腹腔脂肪间隙密度增高模糊等征象有助于判断空腔脏器及肠系膜损伤。     

CT detection of hepatic and splenic injuries: usefulness of liver window settings

OBJECTIVE. This study was designed to assess the usefulness of liver window settings when performing abdominal CT for the detection and characterization of hepatic and splenic injuries. SUBJECTS AND METHODS. We prospectively evaluated helical abdominal CT scans for hepatic and splenic injuries in 300 consecutive patients with blunt abdominal trauma over a 4-month period. There were 204 males and 96 females with a mean age of 34 years (age range, 1-87 years). For each patient, initial CT diagnosis of hepatic or splenic injury was made from images obtained with standard abdominal window settings. CT scans were then immediately reinterpreted using additional images obtained at narrow window width (liver windows). Changes in conspicuity and characterization of injury were recorded. All CT examinations were performed with helical 7-mm collimation at a pitch of 1.5 after oral ingestion of diluted barium and during bolus IV administration of 125 mL of ioversol at a rate of 2-3 mL/sec. RESULTS. We detected hepatic or splenic injuries in 34 patients (11.3%). There were 19 hepatic injuries and 18 splenic injuries. Three patients had injuries to both liver and spleen. Conspicuity of hepatic or splenic injuries was mildly increased (+1 H) on liver windows in 16 patients, whereas the injury was equally conspicuous on both liver window and standard window images in 19 cases. In no case did review of the liver windows result in a change in grade of injury or reveal an injury that was not seen on standard abdominal window images. The total increased cost for printing liver windows was $5748. CONCLUSION. Routine use of liver window settings for abdominal CT in trauma patients has little clinical usefulness and is not cost-effective.     

兔急性闭合性脑挫裂伤后脑血流动态CT灌注成像的实验研究

目的 探讨脑挫裂伤动物模型局部脑血流灌注动态变化规律.方法 40只新西兰大白兔,自由落体法制作闭合性脑挫裂伤模型,外伤后1、3、6、12、24、48及72 h行CT灌注(CTP)检查,源图像传输至工作站进行后处理.选择病变最大层面,测量各时间点脑挫裂伤中央区、周边区及对应镜像区脑血流量(CBF)、脑血容量(CBV)及平均通过时间(MTT).中央区与镜像区、周边区与镜像区CTP各参数进行配对t检验.观察CBF、CBV及MTT演变规律.对照CTP图像,观察脑挫裂伤中央区与周边区病理改变.结果 35只动物建模成功,T_2WI及DWI可见脑挫裂伤局部异常信号.CTP参数变化趋势:(1)外伤各时间点中央区CBF值均显著下降,至12 h降至最低点,24 h开始缓慢增高;1、3、6、12、24、48、72 h时CBF分别为(27.58±18.70)、(20.64±6.50)、(23.38±7.53)、(22.14±10.25)、(25.08±11.01)、(43.08±18.33)、(54.79±14.63)ml·min~(-1)·100 g~(-1),镜像区为(62.28±25.46)、(60.67±16.19)、(67.00±21.34)、(74.46±20.11)、(66.73±11.68)、(81.63±10.99)、(86.16±10.57)ml·min~(-1)·100 g~(-1),外伤区与镜像区各时间点差异有统计学意义(t值分别为4.41、5.57、5.47、6.02、6.44、4.81、10.60,P值均＜0.05);周边区CBF稍减低,1、3 h略明显,此后缓慢增高,与镜像区差异无统计学意义(P值均＞0.05).(2)外伤各时间点中央区CBV值均显著下降,至12 h降至最低点,24 h开始缓慢增高;各时间点中央区CBV分别为(1.74±0.46)、(2.22±0.86)、(2.26±0.44)、(1.15±0.22)、(2.67±0.77)、(2.68±0.72)、(2.86±0.65)ml/100 g,镜像区为(7.27±5.29)、(6.18±1.82)、(6.93±1.86)、(6.66±2.75)、(8.48±2.34)、(8.56±2.38)、(8.83±1.57)ml/100 g,差异有统计学意义(t值分别为3.09、5.38、6.25、4.80、7.82、6.36、8.51,p值均＜0.05);周边区CBV稍减低,1 h与3 h略著,此后缓慢增高,与镜像区差异无统计学意义(P值均＞0.05),上升趋势近似.(3)中央区1～3 h MTT显著延长,3 h后MTT值下降明显,至12 h达到平台期,中央区各时间点MTT分别为(4.88±1.37)、(5.09±1.21)、(4.49±1.33)、(3.44±0.46)、(3.58±0.42)、(3.51±0.73)、(3.30±0.27)s,镜像区为(2.03±0.07)、(2.03±0.04)、(2.04±0.07)、(2.00±0.55)、(2.07±0.20)、(2.06±0.06)、(2.02±0.02)s,各时间点与镜像区差异均有统计学意义(t值分别为5.87、5.95、4.43、7.74、9.02、4.73、4.76,P值均＜0.05).周边区24 h前MTT增加,1～24 h呈逐渐下降趋势,24、72 h时与镜像区差异无统计学意义.镜像区各时间点MTT变化不明显.病理学上中央区出血、坏死、水肿及血管周围间隙增大均较周边区明显.结论 CTP能敏感地发现及监测兔脑挫裂伤后血流动力学变化,脑挫裂伤区血流灌注变化有一定的时间规律,且病变中央区变化较周边区明显.