Computed tomography of blunt abdominal trauma

Experience with over 500 cases at this institution and reports from other institutions have established CT as an accurate and clinically useful tool in the evaluation of patients with blunt abdominal trauma. Careful attention to technique is essential since artifacts may simulate or obscure traumatic lesions. CT is highly sensitive and specific for parenchymal lacerations and for hematomas of solid and hollow abdominal viscera throughout the peritoneal and retroperitoneal spaces. CT has important advantages over radionuclide scintigraphy, angiography, and ultrasonography and has replaced these imaging techniques in acute evaluation of blunt abdominal trauma at some centers. The use of nontherapeutic exploratory laparotomy and diagnostic peritoneal lavage may also be substantially reduced.     

Computed tomography of pediatric blunt abdominal trauma

Computed tomography (CT) is the imaging method of choice in the evaluation of hemodynamically stable children after blunt abdominal trauma. Evaluation with CT will show whether intraperitoneal fluid or blood is present and whether the liver, spleen, kidneys, and pancreas are intact. Although the principal role of CT after blunt abdominal trauma is the assessment of solid viscus injury, an unintended consequence of the increased utilization of CT in this setting is that an increased number of children with hollow viscus injury are being evaluated. CT can reliably depict injury to these hollow viscera, although the diagnosis of such injury is not as straightforward as with solid viscus injury. This essay reviews indications for CT, technique for the performance of CT, and CT findings associated with hollow and solid viscus injury and posttraumatic shock.     

Computed tomography for the assessment of blunt abdominal trauma

Computed tomography (CT) was carried out on 70 patients with blunt abdominal trauma. Damage to the abdominal organs was clearly demonstrated by CT. The positive rates of CT in traumatic lesions were higher than those of ultrasound (US). Intraperitoneal hemorrhage was well demonstrated by US. Serum GPT levels were significantly elevated in patients with liver damage (p less than 0.001). CT proved to be useful for detecting damage to organs in patients with abdominal trauma.     

Computed tomography of retroperitoneal duodenal rupture in blunt abdominal trauma.

Two cases of retroperitoneal duodenum rupture following an upper abdominal blunt trauma are reported. Computed tomography (CT) demonstrates at best extraintestinal fluid and air in the retroperitoneum, especially if acquisition in right lateral decubitus is possible. Drawbacks of the method are also reviewed.     

Computed tomography of the gallbladder.

Computed tomography (CT) was used to study 79 patients with suspected gallbladder disease. First and second generation scanners were used to determine the efficacy of CT in detecting cholecystitis or cholelithiasis. Manifestations of gallbladder disease such as hydrops, opaque and nonopaque gallstones, chronic cholecystitis with thickened inflammatory walls, and secondary liver abscesses can be easily detected. It is a useful technique for individuals in whom the gallbladder has failed to opacity on oral cholecystography. The scanning method is described, and estimates of reliability are given including its accuracy, limitations, and place in the management of gallbladder disease, especially cholelithiasis. When conventional radiographic examinations or ultrasound fail to give definitive diagnostic information, CT can be a useful alternative with an overall diagnostic accuracy greater than 80%.     

Computed tomography arterial portography for assessment of portal vein injury after blunt hepatic trauma

PURPOSE

Intrahepatic portal vein injuries secondary to blunt abdominal trauma are difficult to diagnose and can result in insidious bleeding. We aimed to compare computed tomography arterial portography (CTAP), reperfusion CTAP (rCTAP), and conventional computed tomography (CT) for diagnosing portal vein injuries after blunt hepatic trauma.

METHODS

Patients with blunt hepatic trauma, who were eligible for nonoperative management, underwent CTAP, rCTAP, and CT. The number and size of perfusion defects observed using the three methods were compared.

RESULTS

A total of 13 patients (seven males/six females) with a mean age of 34.5±14.1 years were included in the study. A total of 36 hepatic segments had perfusion defects on rCTAP and CT, while there were 47 hepatic segments with perfusion defects on CTAP. The size of perfusion defects on CT (239 cm³; interquartile range [IQR]: 129.5, 309.5) and rCTAP (238 cm³; IQR: 129.5, 310.5) were significantly smaller compared with CTAP (291 cm³; IQR: 136, 371) (both, P = 0.002).

CONCLUSION

Perfusion defects measured by CTAP were significantly greater than those determined by either rCTAP or CT in cases of blunt hepatic trauma. This finding suggests that CTAP is superior to rCTAP and CT in evaluating portal vein injuries after blunt liver trauma.The liver is one of the most frequently injured solid abdominal organs in the setting of blunt abdominal trauma (1). Fortunately, most patients with blunt hepatic trauma have relatively stable vital signs and need only supportive treatment or transarterial embolization (TAE) (1–9). Only 15% of patients, who present with hemodynamic instability or fail with nonoperative management, require operative intervention to manage their liver injury.Embolic therapy has been shown to have a high success rate in hemodynamically stable patients with blunt hepatic injury. TAE is associated with decreased abdominal infections, decreased transfusions, and decreased length of hospital stay compared with operative management (2, 3, 7). However, angiography can only detect bleeding from the hepatic artery; it cannot locate bleeding from the hepatic or portal vein. In the literature, portal vein injuries are not commonly described and most are the result of penetrating injuries to the extrahepatic portal veins. Mortality after a portal vein injury due to trauma is primarily due to hypovolemic shock and can be as high as 50% or greater (10, 11).Since the intrahepatic portions of the hepatic and portal veins are low pressure systems, they can bleed insidiously. Nevertheless, this subtle bleeding may require multiple transfusions and result in a prolonged hospital stay. Relative to an extrahepatic portal vein injury, patients with an intrahepatic portal vein injury may have relatively stable vital signs and slowly decreasing hemoglobin levels (10, 11). In addition, traumatic occlusion and/or thrombosis of the portal vein may cause large hepatic parenchymal infarction.Computed tomography arterial portography (CTAP) is a useful method based on portal enhancement of the liver by infusion of contrast material through the superior mesenteric artery for evaluating the portal venous system (12–15) and is widely used in patients with hepatic tumors with portal venous invasion (13, 16, 17). CTAP has a high sensitivity and specificity in the evaluation of portal vein thrombosis due to tumor (90% sensitivity, 99% specificity, 95% positive predictive value, 97% negative predictive value) (14). However, few studies have focused specifically on the utility of CTAP in the evaluation of portal vein injury as a result of trauma.The liver has a dual blood supply and receives between 66% and 75% of its blood supply from the hepatic portal vein with the remainder supplied by the hepatic artery (18). CTAP reflects only portal venous perfusion while reperfusion CTAP (rCTAP) reflects hepatic arterial reperfusion. Both rCTAP and conventional computed tomography (CT) are useful for determining certain liver injuries. However, they do not specifically evaluate the portal vein.The purpose of this study was to compare CTAP, rCTAP, and CT for diagnosing portal vein injuries after blunt hepatic trauma. We hypothesized that CTAP would be superior to rCTAP and CT in assessing portal vein injury after blunt hepatic trauma.     

Computed tomography of spine trauma

Nine patients admitted to the hospital for spine trauma were studied with computed tomography. The use of computed tomography minimized patient motion, allowed excellent definition of compromise of the spinal canal by fracture fragments, and better delineated fractures of the neural arches than plain films or tomography. Plain radiographs and computed tomography scans permitted complete evaluation of spine trauma with no additional investigations being necessary.     

Computed tomography of orbital trauma

Ten cases of trauma to the orbit and orbital region are presented to illustrate the efficacy of computed tomography in the radiologic evaluation of these injuries. CT was able to detect subarachnoid hemorrhage, retrobulbar hematoma, orbital cellulitis, foreign bodies, intraglobal and intraorbital air, dislocated lens, blowout, and tripod fractures in these patients.     

Computed tomography of ocular trauma

A wide variety of ocular (eyeball and related soft tissues) injuries resulting from concussive (blunt) and penetrating trauma can be diagnosed by computed tomography (CT). CT can show intraorbital and intraocular emphysema and themorrhage, lens dislocation and subluxation, globe rupture associated with corneal and scleral lacerations, retinal and choroidal detachment, optic nerve injury, and extraocular muscle injury. CT also can localize foreign bodies, and identify injuries caused by them and determine their nature. Not only may CT provide useful information when ocular trauma is clinically suspected, but trauma head and face CT scans may identify unsuspected ocular injuries in the multiple trauma patient. It is imperative that orbital contents be scrutinized carefully on both soft tissue and bone windows of all trauma head and face CT scans in order that clinically significantly ocular injuries not be overlooked.     

Computed tomography of wrist trauma

We devised a rapid and sensitive computed tomography (CT) method to assess the acutely injured wrist, healing carpal fractures and post-traumatic osteonecrosis, when the plain films offer insufficient information. The wrist is positioned in a simple reverse-L-shaped Perspex immobilizer. With the scaphoid as the center of the arc and the long axis of the distal radius as the reference 0 degrees line, sequential coronal scans of the wrist were done in 10 degrees increments in an arc of 40 degrees to give 0 degrees, 10 degrees, 20 degrees, 30 degrees and 40 degrees scans. The 0 degrees and 10 degrees arc scans were best for evaluating the distal radius and ulna and soft tissues, the 10 degrees and 20 degrees scans for the carpal bones other than the scaphoid, and their relation to each other, the 30 degrees and 40 degrees scans, parallel to the long axis of the scaphoid, for fractures of the scaphoid and the hook of the hamate. In addition the 40 degrees scan offered an excellent carpal tunnel view. In 22 patients examined for wrist trauma CT was found to be more accurate than plain films and plain-film tomography in determining the presence of a fracture (4 scaphoid and 1 distal radius), in assessing the degree of osseous union (12) and in evaluating intercarpal fusion (2). In addition CT detected avascular necrosis of the lunate in two patients and erosions of the scaphoid and distal radius attributed to rheumatoid arthritis in one.     

Computed tomography of musculoskeletal trauma

Radiology plays a crucial role in the evaluation of the acutely traumatized patient by providing information that allows timely and appropriate management to be instituted. With few exceptions, notably the skull, plain films remain the primary imaging technique for the diagnosis of skeletal trauma. Computed tomography (CT) has become an important adjunctive procedure in the evaluation and diagnosis of trauma, particularly in complex anatomic areas, including the sternoclavicular joint, the pelvis, and the spine, and in many hospitals has virtually replaced conventional tomography. It may be combined with arthrography or enhanced by intravenous or intrathecal contrast material. This article reviews the uses of CT in the diagnosis and evaluation of musculoskeletal trauma and its complications.     

Computed tomography of the gallbladder: unusual diseases

Abdominal CT has in many cases become the initial radiographic examination to elucidate the cause of obscure abdominal pain, fever of unknown origin, and other difficult diagnostic abdominal problems. Not infrequently, unsuspected disease involving the gallbladder may be encountered. Computed tomography commonly identifies calcified gallstones, occasionally indicates acute cholecystitis, and clearly determines the extent of gallbladder carcinoma. Other less common entities such as gallbladder perforation, porcelain gallbladder, and milk of calcium bile may be diagnosed if suspicion is high and attention directed to anatomic details of the gallbladder and adjacent organs. A review of abdominal CT performed during a 4.5 year period revealed 20 instances of unusual gallbladder diseases in 16 patients. Most often these were encountered incidentally or during CT evaluation of nonspecific abdominal problems.     

Computed tomography in hepatic trauma

Twenty-five patients with hepatic injury from blunt upper abdominal trauma were examined by computed tomography (CT). The spectrum of CT findings was recorded, and the size of the hepatic laceration and the associated hemoperitoneum were correlated with the mode of therapy used in each case (operative vs. nonoperative). While the need for surgery correlated roughly with the size of the hepatic laceration, the size of the associated hemoperitoneum was an important modifying factor. Fifteen patients with hepatic lacerations but little or no hemoperitoneum were managed nonoperatively. CT seems to have significant advantages over hepatic scintigraphy, angiography, and diagnostic peritoneal lavage. By combining information on the clinical state of the patient and CT findings, therapy of hepatic injury can be individualized and the incidence of nontherapeutic laparotomies decreased.     

Computed tomography in acetabular trauma

In a retrospective study of 16 acetabular fractures computed tomography (CT) clarified the type and extent of the injury. Computed tomography demonstrated intra-articular fragments of varying size in seven out of eight patients with fractures of the posterior acetabular margin. Abnormalities of the femoral head were also shown in six patients and the possible aetiology of these is discussed. The additional information provided by CT is likely to help in the management of patients with acetabular injuries.