Using contrast-enhanced helical CT to visualize arterial extravasation after blunt abdominal trauma: incidence and organ distribution.

OBJECTIVE: We evaluated the incidence and organ distribution of arterial extravasation identified using contrast-enhanced helical CT in patients who had sustained abdominal visceral injuries and pelvic fractures after blunt trauma. SUBJECTS AND METHODS: Five hundred sixty-five consecutive patients from four level I trauma centers who had CT scans showing abdominal visceral injuries or pelvic fractures were included in this series. The presence or absence of arterial extravasation, as well as the anatomic sites of arterial extravasation, was noted. We obtained clinical follow-up data, including surgical or angiographic findings. RESULTS: In our series, 104 (18.4%) of 565 patients had arterial extravasation. Of the 104 patients, 81 (77.9%) underwent surgery, embolization, or both. The combined rate of surgery or embolization in patients with arterial extravasation was statistically higher than expected at all four institutions (p <0.001). The spleen was the most common organ injured, occurring in 277 (49.0%) of 565 patients, and arterial extravasation occurred in 49 (17.7%) of 277 patients with splenic injury. Several other visceral injuries were associated with arterial extravasation, including hepatic, renal, adrenal, and mesenteric injuries. CONCLUSION: Based on the limited reports of arterial extravasation in the nonhelical CT literature, the percentage (18%) of clinically stable patients in our study with CT scans showing arterial extravasation was higher than anticipated. This finding likely reflects the improved diagnostic capability of helical CT. Although the spleen and liver were the organs most commonly associated with arterial extravasation, radiologists should be aware that arterial extravasation may be associated with several other visceral injuries.     

Detecting hepatic lesions: the added utility of CT liver window settings

PURPOSE: To prospectively evaluate the utility of adding computed tomographic (CT) liver windows to conventional soft-tissue windows for the detection of hepatic disease. MATERIALS AND METHODS: One of four radiologists experienced in abdominal imaging interpreted 1,175 consecutive abdominal CT scans from one institution. Hepatic images were first interpreted by using standard soft-tissue windows. The number of lesions and confidence in lesion detection were recorded. The liver-window images were then interpreted in conjunction with the soft-tissue-window images, and the number of lesions and confidence in detection were recorded again. The proportion of patients in whom additional lesions were found by using liver windows was determined. RESULTS: On soft-tissue-window and liver-window scans interpreted together, 869 (74%) patients had no hepatic lesions. Thirty-six (3.1%) patients had new lesions seen with the addition of liver windows. Twelve of these 36 patients had no lesions seen on soft-tissue-window scans. Twenty-six of the 36 patients with additional lesions seen had a history of neoplasm. There was a change in diagnosis in 1.7% of the patients with the addition of liver windows and a change in recommendation for follow-up in 0.85%. CONCLUSION: Routine interpretation of liver-window scans for all abdominal CT scans has limited added utility in detecting hepatic disease.     

Helical computed tomography characteristics of splenic and hepatic trauma in children subjected to nonoperative treatment

The purpose of this study was to present the radiological characteristics of abdominal computed tomography (CT) in the follow-up of splenic and hepatic injury in children. Children (n=24) less than 13 years old who had suffered blunt abdominal trauma and were diagnosed with splenic and hepatic injury by CT scan prospectively were enlisted in the study. The CT was performed immediately after the injury was suspected, and 7 and 60 days after the trauma. The clinical course of the patients was observed (red blood transfusion requirement, associated abdominal injuries, and hospital stay). The splenic and hepatic injuries varied from grade II to grade IV of the American Association for the Surgery of Trauma. The CT showed a reduction in the volume of the injury 60 days after the trauma. In this article the radiological findings will be shown and correlated with the clinical course of the patients. This study shows that CT is advantageous for detecting and grading splenic and hepatic injuries. These injuries can be managed nonoperatively in hospitals where CT is available for the evaluation of pediatric patients. Electronic Publication     

Nonoperative management of hepatic trauma

In an attempt to determine whether selective, nonoperative management of hepatic trauma might be efficacious, a retrospective review of liver injuries was undertaken. Of the 48 patients with liver injuries identified, there were 34 men and 14 women with an average age of 28.5 years. Mechanism of injury consisted of blunt trauma in 23 patients, stab wounds in 14 patients, and 11 patients had gunshot wounds. There were 12 grade I injuries, 15 grade II injuries, 17 grade III injuries, 2 grade IV injuries, and 1 grade V injury. Diagnosis of liver trauma was made at the time of exploratory laparotomy in 15 patients and suggested by abdominal computed tomography (CT) scan in 18 patients; the remaining 15 patients had a positive peritoneal lavage which led to exploratory laparotomy. Following blunt trauma, 14 patients, all of whom underwent diagnostic abdominal CT scans which confirmed hepatic injury, had nonoperative treatment. All patients who received nonoperative management maintained stable vital signs and only five required transfusion. None of the patients who were treated nonoperatively developed complications or required delayed laparotomy. There were no deaths in this group. Of the 34 patients undergoing exploratory laparotomy, 19 required either no treatment or minor hepatorrhaphy. However, 17 of 25 patients with penetrating wounds had associated abdominal injuries which required operative treatment. Based on the information obtained in this review, it is recommended that stable patients with isolated hepatic injuries, secondary to blunt trauma confirmed by CT scan, may be managed nonoperatively. Due to the high frequency of associated injuries found in patients with penetrating trauma, nonoperative therapy is not advised.     

Triple-contrast helical CT in penetrating torso trauma: a prospective study to determine peritoneal violation and the need for laparotomy.

OBJECTIVE: A prospective study was performed to determine the usefulness of triple-contrast helical CT in predicting peritoneal violation and the need for laparotomy in the treatment of penetrating torso trauma. SUBJECTS AND METHODS: Triple-contrast helical CT scans were obtained in 104 hemodynamically stable patients with penetrating injuries to the torso (thoracoabdominal region including tangential wounds to the anterior abdomen, flank, back, and pelvis) over a 17-month period. The study group included 54 patients with gunshot wounds and 50 with stab wounds. No patient had a radiographic or clinical indication for immediate laparotomy. A positive finding on CT was defined as evidence of peritoneal violation or injury to the retroperitoneal colon, major vessel, or urinary tract. Patients with a positive CT, except patients with isolated liver injury or free fluid, underwent laparotomy. Patients with a negative finding on CT were initially observed. RESULTS: CT studies were positive in 35 (34%) of 104 patients and negative in 69 (66%) of 104 of patients. Laparotomy was performed in 21 (60%) of 35 patients with positive CT; 19 (86%) of 22 were therapeutic, two (9%) were nontherapeutic, and one (5%) was negative (no injury was found). Nine patients with isolated hepatic injuries were successfully treated without laparotomy. Among patients with a negative CT, 67 (97%) of 69 were treated nonoperatively with success. CT had 100% (19/19) sensitivity, 96% (69/72) specificity, 100% (69/69) negative predictive value, and 97% (101/104) accuracy in predicting the need for laparotomy. CONCLUSION: Triple-contrast helical CT can accurately predict the need for laparotomy and exclude peritoneal violation in penetrating torso trauma including tangential abdominal wounds.     

钝性肝脾肾损伤的CT平扫与增强扫描比较

目的:比较CT平扫与增强扫描对肝脾肾钝性损伤的诊断能力。方法:回顾性分析临床疑似钝性肝脾肾损伤,并经手术和临床观察证实的CT平扫和增强扫描的患者84例。结果:平扫确定的损伤:肝12例,脾25例,肾5例;平扫可疑损伤:肝22例,脾15例,肾5例。增强确定的损伤:肝32例,脾40例,肾12例(全肾梗塞1例,局限性梗塞3例);对比剂外溢(活动性出血)3例;无可疑损伤。平扫无异常而增强确定有损伤:肝10例,脾5例,肾2例。增强显示的损伤灶比平扫范围明显大、病灶多、界限清楚。结论:CT增强扫描显示肝脾肾损伤明显优于平扫,延时扫描有助于发现活动性出血,应常规增强扫描。     

上腹部CT扫描调节骨窗肺窗的意义

目的 :探讨上腹部CT扫描调节骨窗肺窗的意义。材料和方法 :在影像工作站 ,有无癌症病史者各 10 0例的CT图像进行骨窗肺窗的调节。结果 :调窗后 ,癌症病史组 ,病变特性或特征增加及实质性影响最后诊断的变化有显著性差异 ;无癌症病史组 ,病变特性或特征增加及实质性影响最后诊断的变化无显著性差异。癌症病史组的差异大 ,无癌症病史组的差异小。结论 :CT多窗宽窗位调节可增加病变特性的显示和诊断的准确性 ;上腹部CT扫描 ,癌症病史阳性者或临床有高度可疑指数者进行多窗宽窗位调节可提高诊断效益 ,无癌症病史者或临床无可疑指数者不需要进行多窗宽窗位调节。     

CT检查中窗技术的合理应用对提高肝内病灶检出率的意义

目的评价在传统软组织窗基础上加用肝组织窗对提高肝内病灶检出率的意义。方法接受腹部CT增强扫描的859例患者的895张顺序编号的CT片是由两位有经验的放射学医师评价的。所有的肝脏成像均采用两种窗技术进行，即起初软组织窗和随后肝组织窗。逐例记录了两种技术检出的病灶数与符合率。确定了利用肝组织窗有新增病灶的患者比例。对两种窗技术在检出病灶数方面的差异进行了统计学分析。结果在859例中，205例（24％）患者在软组织窗和肝组织窗上有肝脏病灶，其中，40例（14．6％）患者随着肝组织窗的加用，检出的病灶数亦增多。这40例中的14例患者具有在软组织窗上看不见的新增病灶。两种窗技术的病灶检出率有统计学差异（P〈0．05）。结论 单一的软组织窗不足以全部发现肝内病灶，因此，有些病灶容易漏诊，而肝组织窗的加用，可有效提高肝脏病灶的检出率与诊断准确性。     

CT of hemodynamically unstable abdominal trauma

This article is an appraisal of the use of CT in the management of patients with unstable abdominal trauma. We examined 41 patients with abdominal trauma using noncontrast dynamic CT. In 17 patients a postcontrast dynamic CT was also carried out. On CT, 25 patients had hemoperitoneum. Thirteen patients had splenic, 12 hepatic, 6 pancreatic, 8 bowel and mesenteric, 12 renal and 2 vascular injuries. Seven patients had retroperitoneal and 2 patients adrenal hematomas. All but five lesions (three renal, one pancreatic, and one splenic) were hypodense when CT was performed earlier than 8 h following the injury. Postcontrast studies (n = 17), revealed 4 splenic, 3 hepatic, 1 pancreatic, 3 renal, and 2 bowel and mesenteric injuries beyond what was found on noncontrast CT. Surgical confirmation (n = 21) was obtained in 81.81 % of splenic, 66.66 % of hepatic, 83.33 % of pancreatic, 100 % of renal, 100 % of retroperitoneal, and 85.71 % of bowel and mesenteric injuries. The majority of false diagnoses was obtained with noncontrast studies. Computed tomography is a remarkable method for evaluation and management of patients with hemodynamically unstable abdominal trauma, but only if it is revealed in the emergency room. Contrast injection, when it could be done, revealed lesions that were not suspected on initial plain scans. Received: 13 March 1997; Revision received: 1 December 1997; Accepted: 6 May 1998     

CT scanning of children with blunt abdominal trauma – is oral contrast useful?

Purpose: To determine the usefulness of oral contrast in CT scanning of children with blunt abdominal trauma by comparing scans performed with and without oral contrast. Methods: CT scans of 273 children with abdominal trauma and 40 without trauma were reviewed. Results: Of the trauma patients, 116 (43 %) were scanned with oral contrast, 157 (57 %) without. Among the children who underwent laparotomy, CT scanning identified 6 of 6 organ injuries in those scanned with oral contrast and 11 of 12 in those scanned without. CT scanning identified all bowel injuries. The pancreatic body and tail were significantly better visualized in scans with oral contrast. Detection of pancreatic or liver injury was not, however, significantly different in the two groups. Opacification of the bowel by contrast was significantly better in elective than in trauma patients. Conclusion: There was no difference in detection of injuries between children scanned with and without oral contrast.     

Changes in splenic size after abdominal trauma

After blunt abdominal trauma, the spleen often increases in volume on serial computed tomographic (CT) scans. To determine the frequency and significance of such enlargement, the authors performed a retrospective analysis of 44 hemodynamically stable patients who had experienced recent blunt abdominal trauma. The severity of splenic, hepatic, or other visceral injuries seen on each CT scan was numerically scored, and the amount of intraperitoneal fluid was assessed. Twenty-five patients (57%) had over 10% enlargement (average enlargement, 56%) on follow-up scans. Increasing volume did not correlate with clinical deterioration or the need for splenectomy. It did correlate modestly with the amount of blood in the peritoneum on CT scans, the number of units of blood transfused, and two clinical indexes of systemic trauma. Therefore, an enlarging spleen is not a CT indicator of a deteriorating clinical condition. This phenomenon is most likely due to marked adrenergic stimulation after injury and changing fluid volumes.     

Evaluation of abdominal trauma by computed tomography

Computed tomography (CT) was used in the evaluation of 100 patients suffering abdominal trauma. The type of trauma was blunt in 78 patients, penetrating in eight, and iatrogenic in 14. Forty per cent of cases had normal CT scans, while 60% showed substantial abdominal or retroperitoneal injuries. Surgery, clinical follow-up, and repeated radiologic examinations confirmed the accuracy of CT, and there were no cases in which medical or surgical management was inappropriately guided by CT. A wide variety of injuries was detected, including 19 splenic, eight hepatic, six pancreatic, 13 renal, 13 retroperitoneal or abdominal wall, and one intraperitoneal. CT has major advantages over plain radiography, radionuclide imaging, and angiography in assessment of trauma-induced injuries.     

Hepatic and splenic injury in children: role of CT in the decision for laparotomy

Clinical and radiographic records of 274 children who were examined with abdominal computed tomography (CT) after blunt abdominal trauma were retrospectively evaluated to test the hypothesis that CT can assist in decisions to perform laparotomy in children with hepatic or splenic injury. CT demonstrated parenchymal injuries in 36 patients (13%) or 20 livers and 21 spleens. Injury to these organs was categorized as minor (39%), moderate (39%), and severe (21%) according to an assessment of the percentage of parenchymal involvement. Hemoperitoneum was detected in 27 of 36 patients (75%). One of 13 (4.7%) with a moderate to large splenic injury underwent splenorrhaphy because of persistent bleeding. One of 12 (5%) with a moderate to large hepatic injury required late operative intervention due to a large necrotic segment. Both children had a large amount of peritoneal fluid. Two of 16 patients (13%) with moderate to large hemoperitoneum required surgery for liver or splenic injury. The decision for laparotomy should not be based on the extent of injury as shown at CT but on the physiologic condition of the child.     

Helical CT of diaphragmatic rupture caused by blunt trauma

OBJECTIVE: The purpose of this study was to determine the diagnostic sensitivity and specificity of helical CT with sagittal and coronal reformatted images in detecting diaphragmatic rupture after blunt trauma. MATERIALS AND METHODS: Chest and abdominal helical CT scans obtained in 41 patients with suspected diaphragmatic injury after major blunt trauma were reviewed by three observers who were unaware of surgical findings. Coronal and sagittal reformatted images were reviewed for each patient as well. Findings consistent with diaphragmatic injury, such as waistlike constriction of abdominal viscera (i.e., the "collar sign"), intrathoracic herniation of abdominal contents, and diaphragmatic discontinuity were recorded. Sensitivity and specificity of helical CT were calculated on the basis of surgical findings and clinical follow-up. RESULTS: Helical CT was performed preoperatively in 23 patients with diaphragmatic rupture (left, n = 17; right, n = 5; bilateral, n = 1). An additional 18 patients underwent helical CT to further evaluate suspicious findings seen on chest radiography at admission and were found to have an intact diaphragm. Sensitivity for detecting left-sided diaphragmatic rupture was 78% and specificity was 100%. Sensitivity for the detection of right-sided diaphragmatic rupture was 50% and specificity was 100%. The most common CT finding of diaphragmatic rupture was the collar sign, identified in 15 patients (sensitivity, 63%; specificity, 100%). Diaphragmatic discontinuity was seen in four patients. CONCLUSION: Helical CT, especially with the aid of reformatted images, is useful in the diagnosis of acute diaphragmatic rupture after blunt trauma. Helical CT can be used to detect 78% of left-sided and 50% of right-sided injuries.     

Visceral injury without hemoperitoneum: A limitation of screening abdominal sonography for trauma

Abdominal sonography for the detection of hemoperitoneum has become increasingly popular as a screening test for visceral injury after blunt trauma. The purpose of this study was to determine the frequency, severity, and clinical significance (outcome) of abdominal organ injuries that occur without hemoperitoneum on the initial evaluation of blunt abdominal trauma patients.During a 12-month period, 3392 blunt trauma patients were admitted to our center. Sonographic studies were performed as an initial screening evaluation to determine the presence of hemoperitoneum in 772 (22.7%) of these patients. Abdominal visceral injuries were verified by computed tomography (CT) or surgery in 196 (5.8%) of all blunt trauma admissions. Sonography, CT, and operative findings were reviewed to determine the presence or absence of hemoperitoneum in patients with abdominal injury. Patients with abdominal visceral injury without hemoperitoneum were further analyzed to identify the type of injury and the management required.A total of 246 abdominal injuries were identified in 196 patients. Fifty (26%) patients with abdominal visceral injuries diagnosed by admission CT scan had no evidence of hemoperitoneum. Admission sonography performed in 15 (30%) of these 50 patients also showed no evidence of hemoperitoneum. Visceral injuries detected by CT in the patients without hemoperitoneum included 22 of 100 splenic injuries (22%), 18 of 91 hepatic injuries (20%), 12 of 26 renal injuries (46%), and 1 of 9 mesenteric injuries (11%). Surgery was required to manage injuries in 10 of these patients.Up to 26% of blunt trauma patients with abdominal visceral injuries do not have associated hemoperitoneum identified on admission abdominal CT or sonography. Dependence on hemoperitoneum as the sole criterion of abdominal visceral injury after blunt trauma will result in falsely negative examinations and will miss potentially significant injuries.     

Liver and bone window settings for soft-copy interpretation of chest and abdominal CT

OBJECTIVE: We evaluated whether the use of multiple window and level settings on a soft-copy workstation improves diagnostic accuracy on chest and abdominal CT. We hypothesized that routinely using window and level settings during soft-copy interpretation would beneficially affect the final diagnosis without compromising efficiency. MATERIALS AND METHODS: Two hundred three randomly selected abdominal and chest CT scans were interpreted by three radiologists using a four-monitor soft-copy workstation (images per screen, nine; resolution, 2K). After the initial interpretations, all scans were reevaluated by the same radiologists using additional liver and bone window and level settings. Differences in conspicuity and characterization of abnormalities were graded on a three-point scale. RESULTS: Conspicuity and characterization of abnormalities were improved in 67% of abnormal findings (81/121; p = 0.01). Improvement (a finding that substantially affected the final diagnosis) was present in 18% of abnormal findings (22/121; p = 0.04). On average, the evaluation of images at multiple window and level settings required an additional 40 sec per case. CONCLUSION: The use of multiple window and level settings during soft-copy interpretation resulted in improved lesion detectability and characterization with greater diagnostic efficacy. Using soft-copy workstations, radiologists can evaluate images using multiple settings without compromising efficiency.     

Hemoperitoneum as the sole indicator of abdominal visceral injuries: a potential limitation of screening abdominal US for trauma.

PURPOSE: To determine, at screening ultrasonography, the prevalence, severity, and clinical outcome of clinically important abdominal visceral injuries, without associated hemoperitoneum, that result from blunt abdominal trauma. MATERIALS AND METHODS: Computed tomography (CT) was performed at admission in 466 patients with visceral injury. A retrospective review was performed of findings from surgery and contrast material-enhanced spiral and conventional CT performed to verify abdominal visceral injuries in 467 (4%) of 11,188 patients with blunt trauma. These patients were admitted to a level 1 trauma center over 33 months to determine the presence of hemoperitoneum and to identify the grade of injury. Medical records of patients with abdominal visceral injury without hemoperitoneum were reviewed for the management required and for results of focused abdominal sonography for trauma (FAST). RESULTS: A total of 575 abdominal visceral injuries were identified at CT and/or surgery. Findings of CT at admission (n = 156) and of surgery (n = 1) revealed no evidence of hemoperitoneum in 157 (34%) patients with abdominal visceral injury; 26 (17%) of whom also had negative FAST studies. Abdominal visceral injuries diagnosed in patients without hemoperitoneum included 57 (27%) of 210 splenic injuries, 71 (34%) of 206 hepatic injuries, 30 (48%) of 63 renal injuries, four (11%) of 35 mesenteric injuries, and two (29%) of seven pancreatic injuries. Surgical and/or angiographic intervention was required in 26 (17%) patients without hemoperitoneum. CONCLUSION: Reliance on the presence of hemoperitoneum as the sole indicator of abdominal visceral injury limits the value of FAST as a screening diagnostic modality for patients who sustain blunt abdominal trauma.     

Traumatic injuries: imaging and intervention in post-traumatic complications (delayed intervention)

The nonoperative management (NOM) of abdominal trauma has gained increasing acceptance over the past decade. This approach has been extended to severe trauma patients previously considered as candidates for surgery. Consequently, the incidence of delayed and uncommonly encountered complications has increased. Causes of delayed complications are multiple and include: (a) abnormal or insufficient injury healing process; (b) retention of necrotic tissue; (c) secondary infection of initially sterile collections; and (d) underestimation of injury severity. The purpose of this review article is to explain the role of various imaging modalities in detecting post-traumatic delayed complications and to highlight the usefulness of minimally invasive techniques, including laparoscopy, biliary endoscopy, therapeutic angiography and image-guided drainage. Subsequent complications, which do not necessarily negatively influence the final outcome, are often predictable, virtually obligatory consequences of the successful NOM of high-grade or complex abdominal injuries. Between 50 and 60% of those patients with grade-IV or grade-V liver or splenic lacerations require some type of interventional treatment; therefore, indiscriminate discharge of patients with solid organ injury managed conservatively may be potentially harmful. As the incidence of complications is higher for more severe grade-IV or grade-V liver, spleen, or kidney injuries, scheduled follow-up CT scans may be rational in this subset of patients to identify potential complications amenable to early application of interventional techniques. Follow-up CT scans are unnecessary in stable adults or children with low-grade injury. Delayed splenic or hepatic rupture is one of the major concerns because this type of complication remains difficult to predict and historically often requires emergent surgery. These ruptures may benefit from NOM, should the same criteria as for primary rupture be respected. Conversely, parenchymatous focal pooling of contrast on initial CT is a good predictor for the development of delayed vascular malformation. In children, as a large part of splenic and hepatic vascular malformations resolve spontaneously, expectant observation may be indicated provided that a strict imaging follow-up is performed until complete disappearance of these lesions. If needed, embolization of parenchymal vascular lesions should be performed as selectively as possible in order to avoid functional parenchyma loss and to reduce the risk of secondary infection of hematoma or ischemic tissue. Technical improvements, such as microcatheter systems and direct percutaneous approach to targeted lesions, have widened the potential for safe endovascular management of acquired vascular malformations. Advantages and disadvantages relative to the different embolic agents are explained. Endoscopic retrograde pancreatography is the chief investigational tool for detecting biliary and pancreatic ducts injuries. The respective roles of endoscopic, percutaneous and surgical approaches in the management of these complications are discussed. The CT scan and ultrasound-guided drainage provide effective nonoperative options in the management of post-traumatic parenchymatous and (retro)-peritoneal collections. Treatment modalities of less common complications, such as bowel stricture or perforation, mesenteric vascular injuries and renal trauma-induced hypertension, are reviewed.     

Helical computed tomography of liver injuries: A trial of dual phase imaging

This study was performed to evaluate whether consecutive arterial phase and portal venous phase scans of the upper abdomen are contributory in the evaluation of the liver in patients with blunt abdominal trauma. The purpose of the study was to determine whether such dual acquisition using helical computed tomography (HCT) provides improved definition of injuries and significant information about the dynamics of posttraumatic hemorrhage.During a 10-month period, all patients referred for evaluation of blunt abdominal trauma were scanned using a dual phase imaging technique. Two consecutive and comparable scan clusters were programmed to study the upper abdomen, with a slice collimation of 10 mm and a 11 pitch. Intravenous contrast medium was delivered at a rate of 2 ml/sec for a total of 125 ml, with scan delays of 30 and 70 seconds (arterial and venous phases of hepatic enhancement).Thirty-two patients with hepatic lacerations were encountered, and the images from both acquisitions were compared and graded according to lesion conspicuity. The presence of contrast medium extravasation associated with parenchymal injuries was also recorded.In 23 (72%) of the 32 patients, the liver injuries were better defined in the portal venous phase, and in eight (25%) patients, the lesions were equally shown in both phases. In only one case, the lesion was better demonstrated in the arterial phase. Contrast medium extravasation was noted in two patients at the site of liver laceration. In three additional cases, contrast medium extravasation was also noted in associated splenic injuries. In all of these patients, the extravasation (bleeding laceration) was seen only in the images corresponding to the portal venous phase.Dual phase HCT of the upper abdomen does not provide significant additional information in the evaluation of patients with liver injuries resulting from blunt abdominal trauma. With a single scan cluster through the upper abdomen after a 70-second injection-scan delay, lesion definition is optimal, and vascular opacification remains adequate.     

Traumatic injuries: imaging of abdominal and pelvic injuries

The availability of new imaging modalities has altered the diagnostic approach to patients with abdominal and pelvic trauma. Computed tomography and ultrasound have largely replaced diagnostic peritoneal lavage. Ultrasound is used in most trauma centers as the initial imaging technique for the detection of hemoperitoneum and helps to determine the need for emergency laparotomy. Computed tomography allows for an accurate diagnosis of a wide range of traumatic abdominal and pelvic conditions. The speed of single-detector helical and multi-detector row CT (MDCT) permits a rapid CT examination of the seriously ill patient in the emergency room. In particular, the technology of MDCT permits multiple, sequential CT scans to be quickly obtained in the same patient, which is a great advance in the rapid assessment of the multiple-injured patient. The evolving concepts in trauma care promoting non-operative management of liver and splenic injuries creates the need for follow-up cross-sectional imaging studies in these patients. Computed tomography and, less frequently, MR or ultrasound, are used for this purpose.