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.

Helical computed tomography of bowel and mesenteric injuries.

BACKGROUND: The role of computed tomography in diagnosing hollow viscus injury after blunt abdominal trauma remains controversial, with previous studies reporting both high accuracy and poor results. This study was performed to determine the diagnostic accuracy of helical computed tomography in detecting bowel and mesenteric injuries after blunt abdominal trauma in a large cohort of patients. METHODS: One hundred fifty patients were admitted to our Level I trauma center over a 4-year period with computed tomographic (CT) scan or surgical diagnosis of bowel or mesenteric injury. CT scan findings were retrospectively graded as negative, nonsurgical, or surgical bowel or mesenteric injury. The CT scan diagnosis was then compared with surgical findings, which were also graded as negative, nonsurgical, or surgical. RESULTS: Computed tomography had an overall sensitivity of 94% in detecting bowel injury and 96% in detecting mesenteric injury. Surgical bowel cases were correctly differentiated in 64 of 74 cases (86%), and surgical mesenteric cases were correctly differentiated from nonsurgical in 57 of 76 cases (75%). CONCLUSION: Helical CT scanning is very accurate in detecting bowel and mesenteric injuries, as well as in determining the need for surgical exploration in bowel injuries. However, it is less accurate in predicting the need for surgical exploration in mesenteric injuries alone.

Using CT to diagnose tracheal rupture.

OBJECTIVE: A retrospective study was performed to assess CT sensitivity for diagnosing tracheal rupture. Intubated cadaver tracheas were examined to assess endotracheal tube balloon overdistention and deformity and to evaluate the relationship of balloon pressures to tracheal injury. MATERIALS AND METHODS: Neck or chest CT scans of 14 patients with tracheal rupture and 41 control trauma patients with pneumomediastinum but without tracheal injury were reviewed and compared to assess the presence and location of extrapulmonary air, whether direct visualization of tracheal wall disruption was possible, the size and shape of endotracheal tube balloon, signs of transtracheal balloon herniation in intubated patients, and the location of the extratracheal endotracheal tube. Intact and experimentally injured cadaver tracheas were used to evaluate tube balloon pressure and configuration. RESULTS: All 14 patients with tracheal rupture had deep cervical air and pneumomediastinum. Overdistention of the tube balloon occurred in 71% (5/7) of the intubated patients, and balloon herniation occurred in 29% (2/7). Direct tracheal injury was seen in 71% (10/14) of the patients as a wall defect (n = 8) or deformity (n = 2). Overall, CT was 85% sensitive for detecting tracheal injury. Patients with tracheal injury had a significantly lower incidence of pneumothorax (p = 0.01) than did the control group. The CT appearance of balloon herniation through defects in the cadaver tracheas closely mimicked those of patients with tracheal injury. The amount of balloon pressure required to rupture the intubated trachea was extremely high and rupture was difficult to obtain. CONCLUSION: CT can reveal tracheal injury and can be used to select trauma patients with pneumomediastinum for bronchoscopy, leading to early confirmation and treatment.

CT findings after embolization for blunt splenic trauma.

PURPOSE: To determine complications after transcatheter embolization for blunt splenic injury as recognized with computed tomography (CT). MATERIALS AND METHODS: From March 1997 to January 2000, 80 patients underwent transcatheter embolization after blunt splenic injury, of whom 53 underwent abdominal CT examination before and after embolization. Preembolization CT scans were reviewed to determine grade of injury, and postembolization CT scans were reviewed to identify complications secondary to embolization. Arteriography results were reviewed to determine findings and method and location of embolization. RESULTS: Splenic infarcts occurred in 63% of patients after proximal embolization and in 100% of patients after distal embolization. Infarcts after distal embolization tend to be larger and occur just distal to the embolization material, whereas infarcts after proximal embolization tend to be smaller, multiple, and located in the periphery. Most infarcts resolved without sequelae. Seven patients developed gas within an infarct or subcapsular fluid collection. Two collections were drained and found to be sterile and one patient had a splenic abscess at laparotomy. CONCLUSIONS: Infarcts are common after splenic embolization. Gas may be present within an infarct after embolization with Gelfoam; however, the presence of air/fluid level is a better predictor of abscess.

CT criteria for management of blunt liver trauma: correlation with angiographic and surgical findings.

PURPOSE: To determine the contrast material-enhanced computed tomographic (CT) criteria for selection of hemodynamically stable patients with blunt hepatic injury for angiographic evaluation. MATERIALS AND METHODS: Seventy-two patients with blunt liver injury underwent CT and hepatic angiography. Hepatic injuries were graded with CT-based classification. Scans were assessed for evidence of contrast extravasation and laceration or contusion extending into the hepatic vein(s), inferior vena cava, porta hepatis, or gallbladder fossa. Medical, angiographic, and surgical records were reviewed to determine angiographic findings, surgical indications and findings, and outcomes. RESULTS: Compared with hepatic angiography, CT was 65% (11 of 17 patients) sensitive and 85% (41 of 48 patients) specific for detection of arterial vascular injury. When CT severity grades 2 and 3 were analyzed, the sensitivity and specificity of CT were 100% (three of three patients) and 94% (34 of 36 patients), respectively (P <.001). Injury involving at least one major hepatic vein was found in 15 (88%) of 17 patients who required liver-related surgery and in 23 (42%) of 55 of the other patients (P <.01). CONCLUSION: CT-based criteria, including hepatic injury grade, signs of arterial vascular injury, and presence or absence of major hepatic venous involvement assists in selecting patients for hepatic angiography and those at increased risk of ongoing or delayed hepatic bleeding or other posttraumatic complications.

Using CT to diagnose traumatic lumbar hernia.

OBJECTIVE: The objective of this study was to determine the CT findings of traumatic lumbar hernia in 15 patients and to discuss the mechanism and treatment of injury. CONCLUSION: CT can reveal traumatic lumbar hernia and show both the anatomy of disrupted muscular layers and the presence of herniated intraabdominal viscera or retroperitoneal fat.

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.

CT detection of serious internal and skeletal injuries in patients with pelvic fractures.

RATIONALE AND OBJECTIVES: The purpose of this study was to determine the percentage of patients with known pelvic fractures who have additional findings of intraabdominal injury, as diagnosed at abdominal computed tomography (CT), and to determine if patients with specific types or patterns of fractures are more likely to have additional injuries. MATERIALS AND METHODS: The authors reviewed the medical records of 200 consecutive patients (125 women, 75 men; age range, 4-86 years) who had been admitted to a level 1 trauma center with osseous pelvic injury secondary to blunt trauma and who had undergone abdominal CT examinations. Abdominal CT findings in these patients were classified as negative, positive, or minimal and correlated with mechanism of pelvic fracture. RESULTS: Sixty-five (32%) of the 200 patients had negative CT findings, 43 (22%) had findings attributable to the trauma but required no follow-up, and 92 (46%) had positive findings that required nonsurgical management or exploratory laparotomy. Additional pelvic fractures were identified in 63 (32%) patients. The highest prevalence of additional injuries was in patients with Malgaigne fractures (four of 15, 27%) or bilateral pubic rami fractures (six of 18, 33%). CONCLUSION: CT examinations revealed that 135 (68%) of 200 patients with pelvic fractures secondary to blunt trauma had concomitant internal or skeletal injuries and that 92 (46%) patients had injuries severe enough to require nonsurgical management or exploratory laparotomy. Patients with bilateral pubic rami fractures or Malgaigne fractures were particularly prone to additional injuries; therefore, abdominal CT examinations are recommended in these patients.