Multidetector CT: detection of active hemorrhage in patients with blunt abdominal trauma

Does trauma team activation associate with the time to CT scan for those suspected of serious head injuries?

Background

Traumatic brain injury (TBI) constitutes the leading cause of posttraumatic mortality. Practically, the major interventions required to treat TBI predicate expedited transfer to CT after excluding other immediately life-threatening conditions. At our center, trauma responses variably consist of either full trauma activation (FTA) including an attending trauma surgeon or a non-trauma team response (NTTR). We sought to explore whether FTAs expedited the time to CT head (TTCTH).

Methods

Retrospective review of augmented demographics of 88 serious head injuries identified from a Regional Trauma Registry within one year at a level I trauma center. The inclusion criteria consisted of a diagnosis of head injury recorded as intubated or GCS < 13; and CT-head scanning after arriving the emergency department. Data was analyzed using STATA.

Results

There were 58 FTAs and 30 NTTRs; 86% of FTAs and 17% of NTTRs were intubated prehospital out of 101 charts reviewed in detail; 13 were excluded due to missing data. Although FTAs were more seriously injured (median ISS 29, MAIS head 19, GCS score at scene 6.0), NTTRs were also severely injured (median ISS 25, MAIS head 21, GCS at scene 10) and older (median 54 vs. 26 years). Median TTCTH was double without dedicated FTA (median 50 vs. 26 minutes, p < 0.001), despite similar justifiable delays (53% NTTR, 52% FTA). Without FTA, most delays (69%) were for emergency intubation. TTCTH after securing the airway was longer for NTTR group (median 38 vs. 26 minutes, p =0.0013). Even with no requirements for ED interventions, TTCTH for FTA was less than half versus NTTR (25 vs. 61 minutes, p =0.0013). Multivariate regression analysis indicated age and FTA with an attending surgeon as significant predictors of TTCTH, although the majority of variability in TTCTH was not explained by these two variables (R² = 0.33).

Conclusion

Full trauma activations involving attending trauma surgeons were quicker at transferring serious head injury patients to CT. Patients with FTA were younger and more seriously injured. Discerning the reasons for delays to CT should be used to refine protocols aimed at minimizing unnecessary delays and enhancing workforce efficiency and clinical outcome.

Errors in imaging assessment of polytrauma patients

Although the use of multidetector computed tomography (MDCT) has increased the diagnostic quality by reducing the number of missed diagnoses in polytraumatized patients, errors remain a common phenomenon in emergency room setting. MDCT errors, contributing more commonly to missed or delayed diagnoses in polytrauma patients, are diagnostic errors commonly related to perceptual errors or to nonvisual errors. However, in some cases, misdiagnoses can be attributed to technical and methodological errors leading to incomplete or poor-quality imaging. Knowledge of common patterns of error is the most effective way to avoid future errors. The purpose of this article is to highlight the most frequent types of diagnostic errors in evaluating with MDCT of polytrauma patients.

"Blush" on trauma computed tomography: not as bad as we think!

INTRODUCTION

Intravenous contrast extravasation (IVCE) on a trauma computed tomography has been quoted as a reason for intervention (angiographic embolization or operation). The new-generation computed tomographic (CT) scanners identify IVCE with increasing frequency. We hypothesized that most IVCEs do not require an intervention.

METHODS

This study was a retrospective evaluation of trauma patients with IVCE on abdomen or pelvis CT scan (January 2005-December 2009). Along with demographic and hemodynamic variables, the following characteristics of IVCE were examined as potential risk factors for intervention: maximal dimension, small (≤ 1.5 cm) versus large (>1.5 cm), contained versus free, and single versus multiple and location.

RESULTS

Sixty-nine patients with 81 IVCEs were identified: 48 IVCEs occurred in intra-abdominal solid organs, 18 IVCEs in the pelvic retroperitoneal space, and 15 IVCEs in the soft tissues or other locations. Thirty patients (43.5%) were managed without an intervention, and 39 patients (56.5%) required either an immediate (30 patients) or a delayed (9 patients) intervention. Multivariate analysis identified three independent predictors of an intervention: an admission systolic blood pressure of 100 mm Hg or lower, a large ICVE, and an Abbreviated Injury Score of the abdomen of 3 or higher. If all three independent predictors were present, 100% of patients received an intervention.

CONCLUSION

Nearly half of IVCEs on CT scan did not require an intervention. A hypotension at admission, a severe abdominal trauma, and a blush diameter of 1.5 cm or greater predicted the need for intervention.

LEVEL OF EVIDENCE

Therapeutic study, level IV; prognostic study, level III.

A Blood Flow Measurement Robotic System: Ultrasound Visual Servoing Algorithms Under Pulsation and Displacement of an Artery

The purpose of this paper is to propose blood flow measurement algorithms during nonperiodic displacement of an artery by controlling an ultrasound (US) probe. Detecting the position and speed of the bleeding source is required as the first step in treating internal bleeding in emergency medicine. Current methods for detecting a bleeding source, however, involve an invasive approach and cannot quantitatively estimate bleeding speed. Current emergencymedical care therefore requires an alternative system for addressing these problems. In this study, we aim to develop a blood flow measurement system for detecting a bleeding source by using a noninvasive modality, such as a US imaging device. Some problems related to the measurement error still need to be addressed before we can create this system. Specifically, blood flow measurement error in the abdominal area is typically large because the displacement of the artery is large and nonperiodic to adequately control the probe. As the first step in solving these problems, we focused on the displacement of the artery toward the out-ofplane state of the US image and developed measurement algorithms to control the probe, based on respiratory information, during artery displacement. We conducted experimentsmeasuring cross-sectional area and flow rate using an ultrasound phantom containing an artery model and a manipulator equipped with a US probe, BASIS-1. As of this writing, results represent the first experimental validation of the proposed algorithms.

In the workup of patients with obscure gastrointestinal bleed, does 64-slice MDCT have a role?

Purpose:

The purpose was to prospectively determine the sensitivity of 64-slice MDCT in detecting and diagnosing the cause of obscure gastrointestinal bleed (OGIB).

Materials and Methods:

Our study included 50 patients (male 30, female 20) in the age range of 3–82 years (average age: 58.52 years) who were referred to our radiology department as part of their workup for clinically evident gastrointestinal (GI) bleed or as part of workup for anemia (with and without positive fecal occult blood test). All patients underwent conventional upper endoscopy and colonoscopy before undergoing CT scan. Following a noncontrast scan, all patients underwent triple-phase contrast CT scan using a 64-slice CT scan system. The diagnostic performance of 64-slice MDCT was compared to the results of capsule endoscopy, 99m-technetium-labeled red blood cell scintigraphy (99mTc-RBC scintigraphy), digital subtraction angiography, and surgery whenever available.

Results:

CT scan showed positive findings in 32 of 50 patients. The sensitivity, specificity, positive predictive value, and negative predictive values of MDCT for detection of bleed were 72.2%, 42.8%, 81.2%, and 44.4%, respectively. Capsule endoscopy was done in 15 patients and was positive in 10 patients; it had a sensitivity of 71.4%. Eleven patients had undergone 99mTc-RBC scintigraphy prior to CT scan, and the result was positive in seven patients (sensitivity 70%). Digital subtraction angiography was performed in only eight patients and among them all except one patient showed findings consistent with the lesions detected on MDCT.

Conclusion:

MDCT is a sensitive and noninvasive tool that allows rapid detection and localization of OGIB. It can be used as the first-line investigation in patients with negative endoscopy and colonoscopy studies. MDCT and capsule endoscopy have complementary roles in the evaluation of OGIB.

Bleeding due to pelvic fractures in female patients: pictorial review of multidetector computed tomography imaging

Pelvic bone fractures in female patients are a result of high-energy trauma and are a significant cause of morbidity and mortality. Their classification is based on the mechanism of the traumatic impact force and the evaluation of stability or instability of pelvic ring fracture. Vascular hemorrhage is frequently associated with pelvic bone disruption and is the main cause of death in polytrauma female patients. At many trauma centers, multidetector computed tomography (MDCT) has been considered the best modality in the trauma setting as it is also useful in characterizing multiple-body traumatic lesions. Specifically, MDCT angiography can lead to fast recognition of pelvic vascular injuries to triage patients with blunt pelvic trauma and to send those with ongoing arterial hemorrhage to appropriate emergent treatment. At contrast medium enhanced MDCT, extravasation of contrast material is an accurate finding of active bleeding and enables the interventional radiologist to selectively investigate the arteries most likely to be involved with prompt angiographic embolization. The potential sites of hemorrhage include the pelvic bone, the pelvic venous plexus, the major iliac veins, the major iliac arteries, and their peripheral branches. MDCT multiphase protocol can accurately differentiate arterial from venous hemorrhage. This article discusses the use of multiphase contrast medium enhanced MDCT in detecting and characterizing vascular pelvic injuries associated with pelvic fractures in trauma female patients.

Imaging of acute conditions affecting the hepatic vasculature

Liver imaging primarily consists of evaluating the parenchyma and biliary system. However, the liver has a rich, complex vascularity which can also be affected by numerous disease processes. By considering disease processes that primarily affect the hepatic veins, portal veins, and hepatic arteries, an anatomy-based approach of hepatic vascular diseases can be applied to image interpretation to allow rapid diagnosis and prompt initiation of treatment. Computed tomography, magnetic resonance imaging, and ultrasound are all effectively used to evaluate the liver and can play complimentary roles. In this article, the key imaging findings of acute conditions affecting the hepatic veins (passive congestion, acute thrombosis/Budd-Chiari, stenosis), portal veins (thrombosis, phlebitis, stenosis), hepatic arteries (laceration, pseudoaneurysm, thrombosis), and arteriovenous structures (hereditary hemorrhagic telangiectasis, arteriovenous fistula) will be reviewed.

Noninvasive internal bleeding detection method by measuring blood flow under ultrasound cross-section image

The purpose of this paper is to propose noninvasive internal bleeding detection method by using ultrasound (US) image processing under US cross-section image. In this study, we have developed a robotic system for detecting internal bleeding based on the blood flow measured by using a noninvasive modality like an US imaging device. Some problems related to the measurement error, however, still need to be addressed. In this paper, we focused on US image processing under US cross-section image, and constructed blood flow measurement algorithm under US cross-section image for internal bleeding detection. We conducted preliminary blood flow measurement experiments using a phantom containing artery model and a manipulator equipped with a US probe (BASIS-1). The results present the experimental validation of the proposed method.

Transcatheter arterial embolization of spontaneous life-threatening extraperitoneal hemorrhage

PURPOSE

To determine the outcomes of patients with spontaneous extraperitoneal hemorrhage (SEH) referred for endovascular therapy.

MATERIALS AND METHODS

A retrospective analysis included 25 patients (13 male) with 28 spontaneous bleeding events that occurred during the period 1998-2009. All patients had a computed tomography (CT) scan showing extraperitoneal hematoma before angiography. Hematoma location, presence of contrast extravasation or hematocrit level on CT, angiographic findings, vessels that received embolization, angiographic outcome, transfusion requirements, and mortality were recorded. Patients' medications, lowest measured hemoglobin levels, serologic coagulation parameters, and comorbidities were also noted. Mean follow-up was 37.4 months (range 2-132 mo).

RESULTS

Patients had received anticoagulation therapy before 20 of 28 bleeding events. Angiography showed contrast extravasation in 22 (79%) of 28 cases. Angiographic cessation of bleeding with embolization was achieved in all 22 cases. There was extravasation from more than one site in 17 (61%) of 28 cases. There was bleeding in more than one vascular territory in eight (29%) cases. Empiric embolization was performed in three cases. In the 48 hours following angiography, transfusion requirements decreased in 27 (96%) of 28 cases, and there were no deaths. All-cause mortality at 30 days was 29%, at 90 days was 32%, and at 12 months was 43%.

CONCLUSIONS

Multiple bleeding sites are typical in SEH. Transcatheter embolization is a safe and effective treatment; however, mortality is high in the time around angiography.

Multidetector computed tomography of acute vascular injury in blunt abdominal/pelvic trauma: imaging predictors of treatment

PURPOSE

The purpose of this study was to analyze the multidetector computed tomography (MDCT) morphologic characteristics of non-aortic acute vascular injuries (AVI) in patients with blunt abdominopelvic trauma that predict treatment.

METHODS

CT scans of 65 trauma patients with non-aortic AVI were reviewed. AVI morphology was categorized as linear or round. The organ of involvement, location of hemorrhage, initial size of hematoma, and hemodynamic status were recorded. Expansion rates of the hematoma were calculated in 40 patients who had delayed imaging. Multivariate regression was used to analyze the morphologic features of AVI and treatment.

RESULTS

Patients with linear AVI were four times more likely to require aggressive treatment (surgery or embolization) than those with a round morphology, independent of the hemodynamic status. There was no main effect of the organ involved, location of hemorrhage, initial bleed size, or expansion rate on the probability of aggressive treatment.

CONCLUSION

The location, initial size, and expansion rate of AVI are not significant predictors of aggressive treatment with surgery or embolization. Linear morphology of AVI, however, is more likely to require aggressive treatment than round AVI, independent of the hemodynamic status. Linear AVI likely reflects a spurting jet of active extravasation, whereas round AVI likely represents a pseudoaneurysm or slow bleed.

Angiography and embolisation for solid abdominal organ injury in adults - a current perspective

Over the past twenty years there has been a shift towards non-operative management (NOM) for haemodynamically stable patients with abdominal trauma. Embolisation can achieve haemostasis and salvage organs without the morbidity of surgery, and the development and refinement of embolisation techniques has widened the indications for NOM in the management of solid organ injury. Advances in computed tomography (CT) technology allow faster scanning times with improved image quality. These improvements mean that whilst surgery is still usually recommended for patients with penetrating injuries, multiple bleeding sites or haemodynamic instability, the indications for NOM are expanding.

We present a current perspective on angiography and embolisation in adults with blunt and penetrating abdominal trauma with illustrative examples from our practice including technical advice.

Pelvic CT angiography in blunt trauma: imaging findings and protocol considerations. [corrected]

The evolution of multi-row detector computed tomography (MDCT) technology has resulted in evolving applications of CT angiography (CTA) in the trauma setting. In patients with significant blunt pelvic injuries, the immediate diagnosis and characterization of vascular injuries are of significant import given their morbidity and mortality in this patient population. The application of MDCT technology, specifically 64MDCT, to pelvic CTA is useful in evaluating for potential vascular injuries and may be integrated into admission trauma imaging in order to triage patients with blunt pelvic trauma to appropriate emergent intervention. This review will discuss the use of pelvic CTA in blunt pelvic trauma and its utility in detecting and characterizing vascular injury, including the differentiation of arterial from venous hemorrhage. Protocol considerations in pelvic CTA using 64MDCT technology will be detailed as well as the integration of pelvic CTA into torso CT trauma protocols.

Large subdural effusions after angiography mimicking acute subdural hematoma

Contrast enhancement of the brain parenchyma and ventricular and subarachnoidal contrast extravasation are known to be rare complications after intra-arterial angiography. We here describe the first case of extensive contrast extravasation into the subdural space after percutaneous coronary intervention.

Optimized multidetector computed tomographic protocol for the diagnosis of active obscure gastrointestinal bleeding: a feasibility study

OBJECTIVE

The purpose of this feasibility study was to prospectively evaluate an optimized multidetector computed tomographic protocol for the diagnosis of active obscure gastrointestinal bleeding (OGIB).

METHODS

Between October 2006 and February 2008, patients admitted for active OGIB were included in this prospective unicenter study. Water was administered orally and rectally as neutral luminal contrast material. A contrast-enhanced 16-row multidetector computed tomography (MDCT) was performed in the arterial and venous phases. Mesenteric digital subtraction angiography was carried out immediately after MDCT as standard of reference.

RESULTS

Six patients were included in this study. Multidetector computed tomography identified the bleeding site and source in 5 (83%) of the patients. Digital subtraction angiography was performed in 4 patients, and the result was positive in 1 (25%) of the patients. Multidetector computed tomography detected the site and source of bleeding in 2 patients whose digital subtraction angiographic result was negative.

CONCLUSIONS

The results of this feasibility study indicate that optimized MDCT is an excellent diagnostic tool for the diagnosis of active OGIB.

Spontaneous abdominal hemorrhage: causes, CT findings, and clinical implications

OBJECTIVE

The purpose of this article is to present the most common causes of spontaneous abdominal hemorrhage and to review the CT findings that are important in establishing the correct diagnosis and in guiding appropriate therapy.

CONCLUSION

Knowledge of the common CT manifestations of various causes of spontaneous abdominal hemorrhage allows their accurate diagnosis and has a direct impact on clinical decision making.

Radiographic predictors of need for angiographic embolization after traumatic renal injury

BACKGROUND

Although the American Association of the Surgery for Trauma Organ Injury Scale is the gold standard for staging renal trauma, it does not address characteristics of perirenal hematomas that may indicate significant hemorrhage. Angiographic embolization has become well established as an effective method for achieving hemostasis. We evaluated two novel radiographic indicators--perirenal hematoma size and intravascular contrast extravasation (ICE)--to test their association with subsequent angiographic embolization.

METHODS

Among 194 patients with renal trauma between 1999 and 2004, 52 having a grade 3 (n = 33) or grade 4 (n = 19) renal laceration were identified. Computed tomography scans were reviewed by a staff radiologist and urologist blinded to outcomes. ICE was defined as contrast within the perirenal hematoma during the portal venous phase having signal density matching contrast in the renal artery. Hematoma size was determined in four ways: hematoma area (HA), hematoma to kidney area ratio (HKR), difference between hematoma and kidney area (HKD), and perirenal hematoma rim distance (PRD).

RESULTS

Of the 52 patients, 8 had ICE and 4 of these (50%) required embolization, whereas none of the 42 (0%) patients without ICE needed embolization (p = 0.001). Likewise, all four measures of perirenal hematoma size assessed were significantly greater in patients receiving embolization [HA (128.3 vs. 75.4 cm, p = 0.009), HKR (2.75 vs. 1.65, p = 0.008), HKD (76.5 vs. 30.2 cm, p = 0.006), and PRD (4.0 vs. 2.5 cm, p = 0.041)].

CONCLUSION

Perirenal hematoma size and ICE are readily detectible radiographic features and are associated with the need for angiographic embolization.

[Imaging of trauma with multi-detector computed tomography]

Diagnosis of trauma-related injuries is a key task in modern radiology. Early, thorough and accurate detection of potentially life-threatening injuries is crucial for fast and targeted initiation of treatment. Conventional radiography (CR) and ultrasound (US) are well-established and still represent the basic diagnostic tools for trauma imaging. However, a number of studies have shown a lower detection rate of injuries for radiography and ultrasound compared with computed tomography (CT). Multi-detector CT (MDCT) with its shorter scan time and increased accuracy has become the gold standard for many indications in trauma imaging. As MDCT has a higher radiation dose, its use should be restricted and carefully indicated especially when dealing with a younger patient population. Careful optimization of imaging parameters has to be performed to minimize exposure and maximize diagnostic safety. Modern MDCT examinations produce a large number of images, which have to be limited to a reasonable number for interpretation. This review article focuses on optimization of examination protocols and on how to handle the flood of images for viewing and archiving.

A 10-year review of blunt renal artery injuries at an urban level I trauma centre

INTRODUCTION

Little consensus exists over the management of high-grade renal injuries, with continued debate over observation versus invasive surgery. Blunt renal artery injury (BRAI) is a high-grade injury that may result in renal dysfunction, hypertension, or failure.

MATERIALS AND METHODS

Management of BRAI at a level I trauma centre during a decade was retrospectively reviewed to determine incidence, assess management strategy, and evaluate hospital outcomes. Data collected included demographics, injury details, standardised scoring, renal injury grade, haemodynamic stability, diagnostic modalities, medical interventions, mortality, and hospitalisation length.

RESULTS

Thirty-eight BRAI patients (21 Grade IV and 17 Grade V injuries) were admitted, representing 0.16% of trauma admissions, and consisting primarily of young males. Ultrasonography and CT was performed in 92.1% and 76.3% of patients, respectively. Primary management included exploratory laparotomy in 42.9%, angiography and embolisation in 34.3%, and observation in 22.9%. Six nephrectomies and one revascularisation were performed. The incidence of BRAI and use of angiography are higher than those reported in previous studies.

CONCLUSION

Over the past decade, increased use of CT as a diagnostic tool for confirming renal injury in haemodynamically stable patients at our institution may have contributed to the increase in BRAI detection. Higher utilisation of angiography has enabled a more conservative approach. In this series, angiography had a success rate of 94.4%. Angiography and embolisation or observation with careful monitoring are viable management options in haemodynamically stable patients with isolated BRAI.

CEUS in abdominal trauma: multi-center study

The objective of this study was to evaluate the concordance of US and contrast-enhanced US (CEUS) with CT in the assessment of solid organ injury following blunt trauma. Patients underwent complete US examination, including free fluid search and solid organ analysis. CEUS followed, using low-mechanical index techniques and SonoVue. CT was performed within 1 h. Among 156 enrolled patients, 91 had one or more abnormalities (n = 107) at CT: 26 renal, 38 liver, 43 spleen. Sensitivity, specificity, and accuracy for renal trauma at baseline US were 36%, 98%, and 88%, respectively, after CEUS values increased to 69%, 99%, and 94%. For liver baseline US values were 68%, 97%, and 90%; after CEUS were 84%, 99%, and 96%. For spleen, results were 77%, 96%, and 91% at baseline US and 93%, 99%, and 97% after CEUS. Per patient evaluation gave the following results in terms of sensitivity, specificity and accuracy: 79%, 82%, 80% at baseline US; 94%, 89%, and 92% following CEUS. CEUS is more sensitive than US in the detection of solid organ injury, potentially reducing the need for further imaging. False negatives from CEUS are due to minor injuries, without relevant consequences for patient management and prognosis.

Extravasation of intravenous computed tomography scan contrast in blunt abdominal and pelvic trauma

BACKGROUND

Intravenous contrast extravasation (CE) on computed tomography (CT) scan in blunt abdominal trauma is generally regarded as an indication for the need for invasive intervention (either angiography or laparotomy). More recently, improvements in CT scan technology have increased the sensitivity in detecting CE, and, thus, we postulate that not all patients with this finding require intervention.

METHODS

This study is a retrospective review of all patients who underwent a CT scan for blunt abdominal trauma between January 1999 and September 2003. Patterns of injury, associated injuries, management, and outcomes were examined for patients with CE.

RESULTS

Seventy of 1,435 patients (4.8%) demonstrated CE. Mean age was 44 years and mean Injury Severity Score was 39. The location of CE was intra-abdominal in 25, pelvis/retroperitoneum in 39, and both areas in 3 patients. Six patients received supportive treatment for nonsurvivable head injury and were excluded from further analysis. Overall, 30 (47%) patients underwent immediate intervention (angiography or laparotomy) and 34 (53%) were managed nonoperatively. Of those who had initial nonoperative management, overall seven (20.5%) underwent intervention, with the remainder being managed without intervention. The success for nonoperative management was greater for those with pelvic/retroperitoneal CE (4 of 7: 57%) than for intra-abdominal extravasation (23 of 27: 85%).

CONCLUSION

Although evidence of CE may suggest significant vascular injury, our data suggest that not all patients require invasive intervention. Further studies are needed to better define criteria for nonoperative management in patients with CE identified on their initial CT scan.

Multidetector CT evaluation of active extravasation in blunt abdominal and pelvic trauma patients

Timely localization of a bleeding source can improve the efficacy of trauma management, and improvements in the technology of computed tomography (CT) have expedited the work-up of the traumatized patient. The classic pattern of active extravasation (ie, administered contrast agent that has escaped from injured arteries, veins, or urinary tract) at dual phase CT is a jet or focal area of hyperattenuation within a hematoma that fades into an enlarged, enhanced hematoma on delayed images. This finding indicates significant bleeding and must be quickly communicated to the clinician, since potentially lifesaving surgical or endovascular repair may be necessary. Active extravasation can be associated with other injuries to arteries, such as a hematoma or a pseudoaneurysm. Both active extravasation and pseudoaneurysm (unlike bone fragments and dense foreign bodies) change in appearance on delayed images, compared with their characteristics on arterial images. Other clues to the location of vessel injury include lack of vascular enhancement (caused by occlusion or spasm), vessel irregularity, size change (such as occurs with pseudoaneurysm), and an intimal flap (which signifies dissection). The sentinel clot sign is an important clue for locating the bleeding source when other more localizing findings of vessel injury are not present. Timely diagnosis, differentiation of vascular injuries from other findings of trauma, signs of depleted intravascular volume, and localization of vascular injury are important to convey to interventional radiologists or surgeons to improve trauma management.

Acute gastrointestinal bleeding: value of MDCT

Contrast-enhanced multidetector row helical computed tomography (MDCT) scanning is establishing itself as a rapid, noninvasive, and accurate diagnostic method in suspected acute gastrointestinal bleeding. Active bleeding can be depicted as an area of focal high attenuation within the bowel lumen on arterial phase MDCT images. New MDCT technologies facilitate three-dimensional image reconstruction, and higher temporal resolution is available with new MDCT scanner generations. This allows for the acquisition of arterial- and portal-venous phase images of the whole abdomen, revealing potential bleeding sources and simultaneously depict morphological changes in the abdomen, such as intestinal tumors. This article gives an overview of available diagnostic modalities in assessing gastrointestinal (GI) tract hemorrhage, with a special emphasis on new MDCT technology.

Percutaneous injection therapy for blunt splenic trauma guided by contrast-enhanced ultrasonography

OBJECTIVE

The purpose of this study was to investigate the application of contrast-enhanced ultrasonography (CEUS) in managing blunt splenic trauma and the effectiveness of CEUS-guided percutaneous injection therapy.

METHODS

Six patients with grade 3 or 4 splenic injuries as determined by CEUS and contrast-enhanced computed tomography were given hemocoagulase atrox and absorbable cyanoacrylate percutaneously, which were injected into the injury region and active bleeding site, respectively, under CEUS guidance. Immediately after the procedure and 1 and 3 days, 1 and 2 weeks, and 1 and 6 months after the procedure, follow-up CEUS up was performed in all patients.

RESULTS

Among the 6 patients, 4 cases of CEUS-guided hemostatic injection were successful without complications. Rehemorrhage occurred in 1 patient, and a traumatic arteriovenous fistula occurred in another; repeated injection therapy in these 2 patients was effective. During the follow-up, there were no complications, and spleen perfusion recovered gradually.

CONCLUSIONS

Contrast-enhanced ultrasonography can be used to guide percutaneous injection therapy and therefore achieve the goal of using interventional ultrasonography in managing splenic trauma.

Multidetector-row computed tomography (CT) of blunt pancreatic injuries: can contrast-enhanced multiphasic CT detect pancreatic duct injuries?

BACKGROUND

We examined patients of blunt trauma with contrast-enhanced multiphasic computed tomography (CT) and determined if it could detect pancreatic duct injuries.

METHODS

During a 17-month period, 95 patients of blunt abdominal trauma underwent multiphasic CT examinations. The CT grading scales of pancreatic injuries at parenchymal phase, portal venous phase, and equilibrium phase were recorded and compared with surgery, endoscopic retrograde cholangiopancreatography, or discharged diagnosis. The diagnostic values of multiphasic CT and interobserver agreements at different phases were computed.

RESULTS

Of the 95 patients, nine (9.5%) had pancreatic injuries (six with main duct injuries, three without main duct injuries). The interobserver agreement presented in kappa values between two radiologists regarding the integrity or disruption of the main duct were good at parenchymal phase (K = 0.73), portal venous phase (K = 0.64), and equilibrium phase (K = 0.68). The overall accuracies of multiphasic CT in detecting main duct injuries were 97.9% (parenchymal phase), 100.0% (portal venous phase), and 96.8% (equilibrium phase), respectively. The sensitivity (50.0%) and negative predictive value (96.7%) of equilibrium phase CT were the lowest among the three phases of CT scans.

CONCLUSION

The portal venous phase CT was the most accurate scan to detect pancreatic duct injuries. However, equilibrium phase CT might underestimate major pancreatic injuries. Multiphasic CT shows early promise in this clinical application and further multi-institutional studies to verify its accuracy and reveal the optimal CT methodology are needed.

Detection and localization of acute upper and lower gastrointestinal (GI) bleeding with arterial phase multi-detector row helical CT

The purpose of this study was to evaluate the accuracy of multi-detector row helical CT (MDCT) for detection and localization of acute upper and lower gastrointestinal (GI) hemorrhage or intraperitoneal bleeding. Thirty-six consecutive patients with clinical signs of acute bleeding underwent biphasic (16- or 40-channel) MDCT. MDCT findings were correlated with endoscopy, angiography or surgery. Among the 36 patients evaluated, 26 were examined for GI bleeding and 10 for intraperitoneal hemorrhage. Confirmed sites of GI bleeding were the stomach (n = 5), duodenum (n = 5), small bowel (n = 6), large bowel (n = 8) and rectum (n = 2). The correct site of bleeding was identifiable on MDCT in 24/26 patients with GI bleeding. In 20 of these 24 patients, active CM extravasation was apparent during the exam. Among the ten patients with intraperitoneal hemorrhage, MDCT correctly identified the bleeding source in nine patients. Our findings suggest that fast and accurate localization of acute gastrointestinal and intraperitoneal bleeding is achievable on MDCT.

Multidetector computed tomography angiography in detection of active bleeding in renal and liver transplant recipients

OBJECTIVES

The aim of this study was to evaluate the effectivity of multidetector computed tomography angiography (MDCT-A) to detect active bleeding in transplant patients.

MATERIALS AND METHODS

Between 1999 and 2006, 532 patients underwent renal or liver transplantation. MDCT-A was performed on recipients who displayed decreased hemoglobin levels or who had a hematoma during abdominal ultrasound imaging. The MDCT-A used a 16-detector CT device (Siemens, Sensation) with slices 0.75 mm thick after injection of nonionic contrast media (4 mL per second). A multiple intensity projection (MIP) technique was used to maintain angiographic images in the axial and coronal planes.

RESULTS

MDCT-A detected active bleeding among 23 posttransplant patients: 10 of arterial origin and 13 venous, as proven either by angiography or during operation. Among 8 of the 11 patients who underwent angiographic imaging the arterial origin was embolized. For three patients the angiographic evaluation was not helpful to find the bleeding point. A cohort of 5 of 12 patients did not undergo angiographic evaluation and were followed by clinical and ultrasonographic findings. Seven patients underwent re-operating.

DISCUSSION

Management of the patients who were suspected to have active bleeding after renal or liver transplantation was benefitted by MDCT-A as an accurate and feasible screening modality.

Blunt abdominal trauma: current imaging techniques and CT findings in patients with solid organ, bowel, and mesenteric injury

Imaging plays a critical role in the evaluation of patients with blunt abdominal trauma. In most institutions, computed tomography (CT) is the modality of choice when evaluating such patients. The purpose of this review is to highlight current techniques in trauma imaging and to review CT findings associated with solid organ, bowel, mesenteric, and diaphragmatic injury. In particular, emphasis is placed on the use of multidetector CT technology (MDCT), especially 64-row detector CT. The role of various techniques, including the use of oral and intravenous contrast, as well as the potential benefit of delayed imaging, is discussed.

Geriatric Trauma

Elderly trauma patients present unique challenges and face more significant obstacles to recovery than younger patients. Despite overall higher mortality, longer length of stay, increased resource use, and higher rates of discharge to rehabilitation, most elderly trauma patients return to independent or preinjury functional status. Critical to improving these outcomes is an understanding that although similar trauma principles apply to the elderly, these patients require more aggressive evaluation and resuscitation. This article reviews the recent developments in the literature regarding care of the elderly trauma patient.

Transcatheter arterial embolisation in anticoagulant-related haematoma--a current therapeutic option: a report of four patients and review of the literature

The aim of this study is to present the computed tomography (CT) and angiographic findings of life-threatening extraperitoneal haemorrhage complicating anticoagulant therapy, treated with transcatheter arterial embolisation (TAE). CT and angiographic studies of four consecutive patients with large, extraperitoneal anticoagulant-related haematomas (ACH) treated by TAE were retrospectively reviewed. Attention was directed to the location of the haematoma and to the possible presence of active arterial extravasation on CT. Four women (mean age 70 years) with large extraperitoneal ACH's demonstrated on CT as extended rectus sheath haematoma in three and expanding iliopsoas haematoma in one, were successfully treated by TAE of the inferior epigastric (n=3) and lumbar artery (n=1). Two patients were diagnosed by contrast-enhanced CT as having active arterial bleeding within the haematoma requiring TAE. The other two were referred to angiography because of haemodynamic instability. We also reviewed the imaging findings of 26 patients with extraperitoneal ACH's requiring TAE described in the literature. In the reviewed cases, a female predominance was found, the retroperitoneum was the most frequent site and most patients recovered. To conclude, unenhanced CT has proved an excellent modality for the diagnosis of ACH's. TAE has been shown to be an effective and safe method for managing such haematomas when conservative treatment is insufficient. We suggest that whenever a large extraperitoneal ACH is seen on unenhanced CT, a subsequent contrast-enhanced dynamic scan should be performed, unless contraindicated. Enhanced CT has a supplementary role in detecting active bleeding that provides an indication for angiographic therapy. Awareness of this optional treatment improve patient's outcome.

Multislice computed tomography in blunt abdominal trauma

Blunt abdominal trauma is a frequent finding in patients with multiple trauma, and is associated with significant morbidity and mortality. Multislice computed tomography (MSCT), allowing for multiplanar reconstructions and three-dimensional images, has become the imaging modality of choice for these patients. MSCT is indicated in all haemodynamically stable patients with suspected blunt abdominal trauma. A `focussed CT' algorithm, as recommended by the Advanced Trauma Life Support (ATLS®) program, may be useful for patients with isolated abdominal trauma who are conscious and cooperative. For unconscious patients with or without multiple trauma `unfocussed' whole-body MSCT algorithms should be used, as these lead to earlier as well as more accurate diagnosis. MSCT allows for rapid diagnosis of abdominal and retroperitoneal injuries and for grading of solid organ injuries. Active haemorrhage may be detected with accuracy similar to angiography. Even bowel, diaphragmatic and bladder injuries, where CT used to miss a significant number of injuries, can be diagnosed with high accuracy by the new generation of MSCT scanners.

64 MDCT in multiple trauma patients: imaging manifestations and clinical implications of active extravasation

The finding of active hemorrhage on computed tomography (CT) in trauma patients has been shown to have significant clinical implications and has been incorporated into numerous CT grading schema. As CT technology has advanced, the sensitivity for detection of active hemorrhage in the trauma population has significantly improved. Currently, with the improved spatial and temporal resolution afforded by 64 multidetector computed tomography (64 MDCT) technology, the clinical implications of the CT findings of active extravasation may need to be reconsidered. This article illustrates the various imaging manifestations of active extravasation throughout the body using 64 MDCT. Additionally, protocol issues specific to the findings of active hemorrhage using 64 MDCT are detailed, including novel interpretation techniques, which offer aid in detecting and characterizing hemorrhage. Finally, the clinical implication of active extravasation using this new technology is discussed. Although more sensitive to the detection of small hemorrhagic foci and with clinical implications highly dependent upon location, active bleeding remains as a salient finding that affects subsequent clinical management of trauma patients.

Emergency percutaneous treatment of arterial iliac axis ruptures

The objective of this paper is to assess the feasibility and effectiveness of emergency percutaneous treatment of ruptures of the iliac axis. In 5 years, we observed 13 patients (mean age, 62.1 years), 11 with rupture of the external iliac artery and two with rupture of the common iliac artery (six traumatic and seven iatrogenic). All patients were treated with stent grafts. A follow-up was performed with a color Doppler ultrasound at 1, 3, 6, and 12 months during the first year and then yearly. Immediate technical success was obtained in all cases. During a mean follow-up of 22.3 months, one stent-graft occlusion and one infection of a retroperitoneal hematoma occurred. The primary patency rate is 92.3%. Percutaneous treatment is a feasible and safe tool for iliac axis ruptures because it can provide a fast and definitive exclusion of bleeding with a patency rate comparable to surgery and less major morbidity and mortality.