Utilization of a two-material decomposition from a single-source, dual-energy CT in acute traumatic vertebral fractures

Purpose

The purpose of this study is to utilize a two-material decomposition to quantify bone marrow edema on a dual-energy computed tomography (DECT) scanner at the cervical, thoracic, and lumbar spine acute fractures in correlation with short tau inversion recovery (STIR) hyperintensity on magnetic resonance imaging (MRI) in comparison with the normal bone marrow.

Materials and methods

This retrospective institutional review board-approved study gathered patients over 18 years old who had acute cervical, thoracic, or lumbar spinal fractures scanned on a DECT scanner. Those who had a spinal MRI done with bone marrow STIR hyperintensity within 3 weeks of the DECT were included. The water (calcium) and fat (calcium) density (mg/cm3) measurements of the region of interest of the bone marrow were obtained at a normal anatomic equivalent site and at the fracture site where STIR hyperintensity was noted on MRI. A statistical analysis was performed using the paired t-test and Wilcoxon signed rank test (p > 0.05).

Results

A total of 20 patients met the inclusion criteria (males n = 17 males, females n = 3). A total of 32 fractures were analyzed: 19 cervical and 13 thoracolumbar. There were statistically significant differences in the water (43 ± 24 mg/cm3) and fat (36 ± 31 mg/cm3) density (mg/cm3) at the acute thoracic and lumbar spine fractures in correlation with edema on STIR images (both paired t-test <0.001, both Wilcoxon signed ranked test p < 0.01). There were no significant differences in the water (-10 ± 46 mg/cm3) or fat (+7 ± 50 mg/cm3) density (mg/cm3) at the cervical spine fractures.

Conclusion

The DECT two-material decomposition using water (calcium) and fat (calcium) analyses has the ability to quantify a bone marrow edema at the acute fracture site in the thoracic and lumbar spine.

Hematocrit and lactate trends help predict outcomes in trauma independent of CT and other clinical parameters

Background

Hematocrit and lactate have an established role in trauma as indicators of bleeding and cell death, respectively. The wide availability of CT imaging and clinical data poses the question of how these can be used in combination to predict outcomes.

Purpose

To assess the utility of hematocrit or lactate trends in predicting intensive care unit (ICU) admission and hospital length of stay (LOS) in patients with torso trauma combined with clinical parameters and injury findings on CT.

Materials and Methods

This was a single-center retrospective study of adults with torso trauma in one year. Trends were defined as a unit change per hour. CT findings and clinical parameters were explanatory variables. Outcomes were ICU admission and hospital LOS. Multivariate logistic and negative binomial regression models were used to calculate the odds ratio (OR) and incident rate ratio (IRR).

Results

Among 840 patients, 561 (72% males, age 39 ± 18) were included, and 168 patients (30%) were admitted to the ICU. Decreasing hematocrit trend [OR 2.54 (1.41-4.58), p = 0.002] and increasing lactate trend [OR 3.85 (1.35-11.01), p = 0.012] were associated with increased odds of ICU admission. LOS median was 2 (IQR: 1-5) days. Decreasing hematocrit trend [IRR 1.37 (1.13-1.66), p = 0.002] and increasing lactate trend [2.02 (1.43-2.85), p < 0.001] were associated with longer hospital LOS.

Conclusion

Hematocrit and lactate trends may be helpful in predicting ICU admission and LOS in torso trauma independent of organ injuries on CT, age, or admission clinical parameters.

The Public Perception of CT Colonography versus Colonoscopy via Sentiment Analysis of Social Media

AIMS

The purpose of our study is to understand the public perception of CT colonography in comparison to optical colonoscopy as a colorectal cancer screening technique.

MATERIALS AND METHODS

In this observational study, we collected all English-language tweets from 1/1/2015 until 9/1/2021 containing terms related to CT colonography (CTC) and terms related to optical colonoscopy. The tweets were given sentiment scores using Twitter-roBERTa-base, a natural language processing model. These scores were then used to classify tweets into positive, neutral, and negative categories. The number of negative, positive, and neutral tweets were tabulated.

RESULTS

A total of 4,709 tweets from 2,194 users relating to CTC were collected. Of these tweets, 9.81% were negative, 68.52% were neutral, and 21.63% were positive. In comparison, a total of 445,969 tweets from 261,209 users were collected relating to optical colonoscopy. Of these tweets, 31.8% were negative, 51.3% were neutral, and 16.9% were positive.

CONCLUSION

The public awareness of CT colonography remains limited in comparison to optical colonoscopy, with Twitter volume relating to CTC being around 1/100th the volume of optical colonoscopy. There is a higher proportion of negative tweets towards colonoscopy. The lower proportion of a negative tweets towards CTC may be helpful in encouraging its use as an alternative to optical colonoscopy with the aim of increasing uptake of colorectal cancer screening.

Social determinants of health and the prediction of missed breast imaging appointments

BACKGROUND

Predictive models utilizing social determinants of health (SDH), demographic data, and local weather data were trained to predict missed imaging appointments (MIA) among breast imaging patients at the Boston Medical Center (BMC). Patients were characterized by many different variables, including social needs, demographics, imaging utilization, appointment features, and weather conditions on the date of the appointment.

METHODS

This HIPAA compliant retrospective cohort study was IRB approved. Informed consent was waived. After data preprocessing steps, the dataset contained 9,970 patients and 36,606 appointments from 1/1/2015 to 12/31/2019. We identified 57 potentially impactful variables used in the initial prediction model and assessed each patient for MIA. We then developed a parsimonious model via recursive feature elimination, which identified the 25 most predictive variables. We utilized linear and non-linear models including support vector machines (SVM), logistic regression (LR), and random forest (RF) to predict MIA and compared their performance.

RESULTS

The highest-performing full model is the nonlinear RF, achieving the highest Area Under the ROC Curve (AUC) of 76% and average F1 score of 85%. Models limited to the most predictive variables were able to attain AUC and F1 scores comparable to models with all variables included. The variables most predictive of missed appointments included timing, prior appointment history, referral department of origin, and socioeconomic factors such as household income and access to caregiving services.

CONCLUSIONS

Prediction of MIA with the data available is inherently limited by the complex, multifactorial nature of MIA. However, the algorithms presented achieved acceptable performance and demonstrated that socioeconomic factors were useful predictors of MIA. In contrast with non-modifiable demographic factors, we can address SDH to decrease the incidence of MIA.

Use of MR in Pancreaticobiliary Emergencies

This article presents the MR protocols, imaging features, diagnostic criteria, and complications of commonly encountered emergencies in pancreaticobiliary imaging, which include pancreatic trauma, bile leak, acute cholecystitis, biliary obstruction, and pancreatitis. Various classifications and complications that can arise with these conditions, as well as artifacts that may mimic pathology, are also included. Finally, the emerging utility of abbreviated MR protocols is discussed.

Quantification of bone marrow edema using dual-energy CT at fracture sites in trauma

PURPOSE

The purpose of our study was to analyze the change in water and fat density within the bone marrow using the GE Revolution dual-energy computed tomography (DECT) platform using two-material decomposition analyses at extremity, spine, and pelvic fracture sites compared to normal bone marrow at equivalent anatomic sites in adult patients who sustained blunt trauma.

METHODS

This retrospective study included 26 consecutive adults who sustained blunt torso trauma and an acute fracture of the thoracolumbar vertebral body, pelvis, or upper and lower extremities with a total of 32 fractures evaluated. Two-material decomposition images were analyzed for quantitative analysis. Statistical analysis was performed using the paired t-test and Shapiro-Wilk test for normality.

RESULTS

There were statistically significant differences in the water and fat densities in the bone marrow at the site of an extremity, vertebral body, or pelvic fracture when compared to the normal anatomic equivalent (p < 0.01).

CONCLUSION

In this preliminary study, DECT basis material images, using water (calcium) and fat (calcium) decomposition illustrated significant differences in water and fat content between fracture sites and normal bone in a variety of anatomical sites.

The Impact of Social Determinants of Health on Lung Cancer Screening Utilization

PURPOSE

The purpose of this study was to understand how social determinants of health might influence lung cancer screening (LCS) adherence.

METHODS

All LCS low-dose CT appointments scheduled at an urban, tertiary care academic medical center in the New England region between January 1, 2015, and December 31, 2018, were included. Demographics, insurance type, information on social determinants of health, and appointment status were obtained from the electronic medical records. Multivariate logistic regression was performed to evaluate the associations between the appointment status and the explanatory variables.

RESULTS

During the study period, 2,797 patients had 4,747 scheduled LCS appointments. Forty-one percent of patients had at least one missed appointment, and 32.7% of all scheduled appointments were missed. The retention rate of patients after the baseline examination was approximately 50%. Self-reported Black race was independently associated with 1.5 times the odds of missing appointments compared with White race (P = .012). Patients with Medicaid had 6.1 times the odds of missing appointments compared with patients with private insurance and 4.6 times the odds of missing appointments compared with patients with Medicare (P < .0001). Housing insecurity was a risk factor for failing to follow up after the baseline examination, with an odds ratio of 5.3 (P = .0013).

CONCLUSIONS

The high rate of missed LCS appointments underscores the need to improve screening compliance. The identification of specific social determinants of health that contribute to disparities in access to LCS could empower policymakers, hospital systems, and providers to use targeted interventions to promote more equitable access.

Acute cholecystitis: diagnostic value of dual-energy CT-derived iodine map and low-keV virtual monoenergetic images

PURPOSE

To compare conventional and dual-energy CT (DECT) for the diagnosis of acute cholecystitis and gangrene.

METHODS

Fifty-seven consecutive adult patients with abdominal pain who underwent IV contrast-enhanced abdominal DECT on a dual-layer (dlDECT) or rapid-switching (rsDECT) scanner from September, 2018 to April, 2021 with cholecystectomy and pathology-confirmed cholecystitis were retrospectively reviewed, and compared with 57 consecutive adult patients without cholecystitis from the same interval scanned with DECT. Images were reviewed independently by two abdominal radiologists with 12 and 16 years of experience in two sessions 4 weeks apart, blinded to clinical data. Initially, only blended reconstructions (simulating conventional single-energy CT images) were reviewed (CT). Subsequently, CT and DECT reconstructions including low-keV virtual monoenergetic images and iodine maps were reviewed. Gallbladder fossa hyperemia, pericholecystic fluid, subjective presence of gangrene, heterogeneous wall enhancement, sloughed membranes, intramural air, abscess, overall impression of the presence of acute cholecystitis, and intramural iodine density were assessed.

RESULTS

Gallbladder fossa hyperemia was detected with increased sensitivity on DECT (R1, 61.4%; R2, 75.4%) vs. CT (R1, 22.8%; R2, 15.8%). DECT showed increased sensitivity for gangrene (R1, 24.6%; R2, 38.6%) vs. CT (R1, 5.3%; R2, 14%), heterogeneous wall enhancement (DECT: R1, 33.3%; R2, 63.2% vs. CT: R1, 7%; R2, 31.6%), and cholecystitis (DECT: R1, 86%; R2, 89.5% vs. CT: R1, 77.2%; R2, 70.2%). In addition, DECT was more sensitive for the detection of acute cholecystitis (R1, 86%; R2, 89.5%) vs. CT (R1, 77.2%; R2, 70.2%). Iodine density threshold of 1.2 mg/ml, 0.8 mg/mL, and 0.5 mg/mL showed specificity for gangrenous cholecystitis of 78.26%, 86.96%, and 95.65%, respectively, using the rsDECT platform.

CONCLUSION

DECT showed improved sensitivity compared to conventional CT for detection of acute cholecystitis. Iodine density measurements may be helpful to diagnose gangrene.

American Society of Emergency Radiology Multicenter Blunt Splenic Trauma Study: CT and Clinical Findings

Background Treatment of blunt splenic trauma (BST) continues to evolve with improved imaging for detection of splenic vascular injuries. Purpose To report on treatments for BST from 11 trauma centers, the frequency and clinical impact of splenic vascular injuries, and factors influencing treatment. Materials and Methods Patients were retrospectively identified as having BST between January 2011 and December 2018, and clinical, imaging, and outcome data were recorded. Patient data were summarized descriptively, both overall and stratified by initial treatment received (nonoperative management [NOM], angiography, or surgery). Regression analyses were used to examine the primary outcomes of interest, which were initial treatment received and length of stay (LOS). Results This study evaluated 1373 patients (mean age, 42 years ± 18; 845 men). Initial treatments included NOM in 849 patients, interventional radiology (IR) in 240 patients, and surgery in 284 patients. Rates from CT reporting were 22% (304 of 1373) for active splenic hemorrhage (ASH) and 20% (276 of 1373) for contained vascular injury (CVI). IR management of high-grade injuries increased 15.6%, from 28.6% (eight of 28) to 44.2% (57 of 129) (2011-2012 vs 2017-2018). Patients who were treated invasively had a higher injury severity score (odds ratio [OR], 1.04; 95% CI: 1.02, 1.05; P < .001), lower temperature (OR, 0.97; 95% CI: 0.97, 1.00; P = .03), and a lower hematocrit (OR, 0.96; 95% CI: 0.93, 0.99; P = .003) and were more likely to show ASH (OR, 8.05; 95% CI: 5.35, 12.26; P < .001) or CVI (OR, 2.70; 95% CI: 1.64, 4.44; P < .001) on CT images, have spleen-only injures (OR, 2.35; 95% CI: 1.45, 3.8; P < .001), and have been administered blood product for fewer than 24 hours (OR, 2.35; 95% CI: 1.58, 3.51; P < .001) compared with those chosen for NOM, after adjusting for key demographic and clinical variables. After adjustment, factors associated with a shorter LOS were female sex (OR, 0.84; 95% CI: 0.73, 0.96; P = .009), spleen-only injury (OR, 0.72; 95% CI: 0.6, 0.86; P < .001), higher admission hematocrit (OR, 0.98; 95% CI: 0.6, 0.86; P < .001), and presence of ASH at CT (OR, 0.74; 95% CI: 0.62, 0.88; P < .001). Conclusion Contained vascular injury and active splenic hemorrhage (ASH) were frequently reported, and rates of interventional radiologic management increased during the study period. ASH was associated with a shorter length of stay, and patients with ASH had eight times the odds of undergoing invasive treatment compared with undergoing nonoperative management. © RSNA, 2021 See also the editorial by Patlas in this issue.

Pancreatic Trauma: Imaging Review and Management Update

Traumatic injuries of the pancreas are uncommon and often difficult to diagnose owing to subtle imaging findings, confounding multiorgan injuries, and nonspecific clinical signs. Nonetheless, early diagnosis and treatment are critical, as delays increase morbidity and mortality. Imaging has a vital role in diagnosis and management. A high index of suspicion, as well as knowledge of the anatomy, mechanism of injury, injury grade, and role of available imaging modalities, is required for prompt accurate diagnosis. CT is the initial imaging modality of choice, although the severity of injury can be underestimated and assessment of the pancreatic duct is limited with this modality. The time from injury to definitive diagnosis and the treatment of potential pancreatic duct injury are the primary factors that determine outcome following pancreatic trauma. Disruption of the main pancreatic duct (MPD) is associated with higher rates of complications, such as abscess, fistula, and pseudoaneurysm, and is the primary cause of pancreatic injury-related mortality. Although CT findings can suggest pancreatic duct disruption according to the depth of parenchymal injury, MR cholangiopancreatography and endoscopic retrograde cholangiopancreatography facilitate direct assessment of the MPD. Management of traumatic pancreatic injury depends on multiple factors, including mechanism of injury, injury grade, presence (or absence) of vascular injury, hemodynamic status of the patient, and associated organ damage. ^©RSNA, 2020 See discussion on this article by Patlas.

Liver trauma: hepatic vascular injury on computed tomography as a predictor of patient outcome

OBJECTIVES

To evaluate hepatic vascular injury (HVI) on CT in blunt and penetrating trauma and assess its relationship to patient management and outcome.

METHOD AND MATERIALS

This retrospective study was IRB approved and HIPAA compliant. Informed consent was waived. Included were patients ≥ 16 years old who sustained blunt or penetrating trauma with liver laceration seen on a CT performed at our institution within 24 h of presentation over the course of 10 years and 6 months (August 2007-February 2018). During this interval, 171 patients met inclusion criteria (123 males, 48 females; mean age 34; age range 17-80 years old). Presence of HVI was evaluated and liver injury was graded in a blinded fashion by two radiologists using the 1994 and 2018 American Association for the Surgery of Trauma (AAST) liver injury scales. Hospital length of stay and treatment (angioembolization or operative) were recorded from the electronic medical record. Multivariate linear regressions were used to determine our variables' impact on the length of stay, and logistic regressions were used for categorical outcomes.

RESULTS

Of the included liver trauma patients, 25% had HVI. Patients with HVI had a 3.2-day longer length of hospital stay on average and had a 40.3-fold greater odds of getting angioembolization compared to those without. Patients with high-grade liver injury (AAST grades IV-V, 2018 criteria) had a 3.2-fold greater odds of failing non-operative management and a 14.3-fold greater odds of angioembolization compared to those without.

CONCLUSION

HVI in liver trauma is common and is predictive of patient outcome and management.

KEY POINTS

• Hepatic vascular injury occurs commonly (25%) with liver trauma. • Hepatic vascular injury is associated with increased length of hospital stay and angioembolization. • High-grade liver injury is associated with failure of non-operative management and with angioembolization.

Imaging Acetabular Fractures

Acetabular fractures are encountered by radiologists in a wide spectrum of practice settings. The radiologist's value in the acute and long-term management of acetabular fractures is augmented by familiarity with systematic computed tomography-based algorithms that streamline and simplify Judet-Letournel fracture typing, together with an appreciation of the role of imaging in initial triage, operative decision making, postoperative assessment, prognostication, and evaluation of complications. The steep increase in incidence of acetabular fractures in the elderly over the past several decades places special emphasis on familiarity with geriatric fracture patterns.

Biliary and pancreatic ductal dilation in patients on methadone maintenance therapy

PURPOSE

To determine whether the diameter of intrahepatic and extrahepatic bile ducts and pancreatic ducts in patients on methadone maintenance therapy is increased when compared with control subjects.

METHODS

Between January 1, 2000 and March 15, 2013, a total of 97 patients (mean age 49.9, range 22-79, 65 male, 32 female) were identified who were receiving chronic methadone maintenance therapy (MMT) when they underwent imaging with abdominal MRI or a contrast-enhanced abdominopelvic CT. A group of 97 consecutive non-MMT control patients (mean age 51.4, range 21-86, 45 male, 52 female) who underwent imaging with abdominal MRI or contrast-enhanced abdominopelvic CT were identified. Patients with known pancreaticobiliary pathology that may confound biliary ductal measurements were excluded. Blinded interpretation was performed, documenting the diameters of the intrahepatic and extrahepatic bile ducts and pancreatic ducts. Descriptive statistics were performed.

RESULTS

Patients on MMT demonstrated increased bile duct diameter, with an average increase in duct diameter of 2.39 mm for the common bile duct (p < 0.001; 95% CI 1.88-2.90 mm), 1.43 mm for the intrahepatic bile ducts (p < 0.001; 95% CI 1.12-1.74 mm), and 0.90 mm for the pancreatic duct (p < 0.001; 95% CI 0.64-1.16 mm). No statistically significant correlation was found between ductal diameters and the daily dose of methadone.

CONCLUSION

Patients on methadone maintenance therapy demonstrate significantly increased intra- and extrahepatic bile duct and pancreatic duct diameter when compared with controls. There was no correlation between the dose of methadone and ductal diameter.

Iatrogenic, blunt, and penetrating trauma to the biliary tract

Iatrogenic and traumatic bile leaks are uncommon. However, given the overall increase in number of hepatobiliary surgeries and the paradigm shift toward nonoperative management of patients with liver trauma, they have become more prevalent in recent years. Imaging is essential to establishing early diagnosis and guiding treatment as the clinical signs and symptoms of bile leaks are nonspecific, and a delay in recognition of bile leaks portends a high morbidity and mortality rate. Findings suspicious for a bile leak at computed tomography or ultrasonography include free or contained peri- or intrahepatic low density fluid in the setting of recent trauma or hepatobiliary surgery. Hepatobiliary scintigraphy and magnetic resonance cholangiopancreatography (MRCP) with hepatobiliary contrast agents can be used to detect active or contained bile leak. MRCP with hepatobiliary contrast agents has the unique ability to reveal the exact location of bile leak, which often governs whether endoscopic management or surgical management is warranted. Percutaneous transhepatic cholangiography and fluoroscopy via an indwelling catheter that is placed either percutaneously or surgically are useful modalities to guide percutaneous transhepatic biliary drain placement which can provide biliary drainage and/or diversion in the setting of traumatic biliary injury. Surgical treatment of a bile duct injury with Roux-en-Y hepaticojejunostomy is warranted if definitive treatment cannot be accomplished through percutaneous or endoscopic means.

Utility of MDCT findings in predicting patient management outcomes in renal trauma

PURPOSE

The purpose of this study is to assess the utility of computed tomography (CT) in predicting clinical outcomes in renal trauma.

MATERIALS/METHODS

This retrospective study was IRB approved and HIPAA compliant; informed consent was waived. One-hundred-sixty-two, trauma-related renal injuries (157 adults) from January 01, 2006 to December 31, 2013 were included in this retrospective study. CT findings of vascular and collecting system (CS) injuries were recorded, and American Association for the Surgery of Trauma (AAST) renal injury grades were assigned. Fisher's exact test evaluated correlations between AAST grade and active hemorrhage, AAST grade and surgical/endovascular therapy, active hemorrhage and surgical/endovascular therapy, and size of perinephric hematomas and CS injuries. The unpaired t test correlated to the size of perinephric hematomas in CS injuries diagnosed on initial versus repeat imaging.

RESULTS

AAST grades were as follows: 120 grades I-III and 42 grade IV/V. Active hemorrhage was diagnosed in 25 (15%) patients and CS injury in 22 (14%) patients. Seven (8%) patients received surgical/endovascular therapy. There were statistically significant correlations between AAST grade and active hemorrhage (p = 0.003), active hemorrhage and surgical/endovascular therapy (p < 0.0001), and large perinephric hematomas (>2 cm) and CS injuries (p < 0.0001). There was no significant correlation between AAST grade and surgical/endovascular therapy (p = 0.08). Of the CS injuries (50%), 11/22 had no evidence of CS injury on initial imaging, being detected on follow-up CT. These "masked cases" demonstrated significant differences in perinephric hematoma size when compared to CS injuries diagnosed on initial imaging (p = 0.01).

CONCLUSION

Active hemorrhage in renal trauma is a significant predictor of surgical/endovascular therapy, in contradistinction to the AAST grade. In collecting system injuries, a large fraction was not detectable on initial CT, supporting the need for repeat imaging in cases with large perinephric hematomas.

Damage control surgery: use of diagnostic CT after life-saving laparotomy

Damage control surgery (DCS) is a limited exploratory laparotomy that is performed in unstable trauma patients who, without immediate intervention, would acutely decompensate. Patients usually present with shock physiology and metabolic derangements including acidosis, hypothermia, and coagulopathy. Delayed medical correction of these metabolic derangements leads to an irreversible state of coagulopathic hemorrhagic shock and inevitable patient demise. Therefore, once a patient meets DCS criteria, a limited exploratory laparotomy is performed to stabilize life-threatening injury and expedite initiation of medical resuscitation in the intensive care unit (ICU). The surgeon plans to return to the operating room for definitive surgical treatment once the patient is hemodynamically stabilized and the metabolic derangements have been corrected. DCS patients are frequently sent to the ICU with an open abdomen and purposefully retained surgical equipment. The lack of response to resuscitation efforts, persistent hypotension, tachycardia, and/or the development of sepsis are common indications for this patient population to undergo CT imaging. The indications and findings of multi-detector CT (MDCT) in patients post-DCS have not been thoroughly evaluated in the radiology literature. A radiologist's knowledge of the DCS protocol and pre-imaging surgical interventions helps optimize the MDCT protocol. This enhances the radiologist's ability to evaluate for failure of surgical interventions performed prior to imaging and to search for injuries in areas that were not explored or that were missed during the initial surgical exploration.

Biliary imaging: multimodality approach to imaging of biliary injuries and their complications

Although traumatic and iatrogenic bile leaks are rare, they have become more prevalent in recent years due to an increased propensity toward nonsurgical management of patients with liver trauma and an overall increase in the number of hepatobiliary surgeries being performed. Because clinical signs and symptoms of bile leaks are nonspecific and delay in the recognition of bile leaks is associated with high morbidity and mortality rates, imaging is crucial for establishing an early diagnosis and guiding the treatment algorithm. At computed tomography or ultrasonography, free or contained peri- or intrahepatic low-attenuation (low-density) fluid in the setting of recent trauma or hepatobiliary surgery should raise suspicion for a bile leak. Hepatobiliary scintigraphy and magnetic resonance (MR) cholangiopancreatography with hepatobiliary contrast agents can help detect active or contained bile leaks. MR cholangiopancreatography with hepatobiliary contrast agents has the added advantage of being able to help localize the bile leak, which in turn can help determine if endoscopic management is sufficient or if surgical management is warranted. Endoscopic retrograde cholangiopancreatography may provide diagnostic confirmation and concurrent therapy when nonsurgical management is pursued. A multimodality imaging approach is helpful in diagnosing traumatic or iatrogenic biliary injuries, accurately localizing a bile leak, and determining appropriate treatment.

Ileal pouch-anal anastomosis surgery: anatomy, postoperative complications, and image-guided intervention

Total proctocolectomy with ileal pouch-anal anastomosis (IPAA) surgery has become the surgical procedure of choice for chronic ulcerative colitis and familial adenomatous polyposis. Since its introduction in 1978, the technique of ileal pouch-anal anastomosis has improved and is commonly performed. Although associated with low mortality, postsurgical complications are frequent with which the radiologist should be familiar. An understanding of surgical technique and postsurgical anatomy facilitates the diagnosis of these frequently encountered complications and governs their potential image-guided intervention.

CT imaging of blunt traumatic bowel and mesenteric injuries

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