David D. B. Bates

Use of Magnetic Resonance in Pancreaticobiliary Emergencies.

This article presents the magnetic resonance protocols, imaging features, diagnostic criteria, and complications of commonly encountered emergencies in pancreaticobiliary imaging. Pancreatic trauma, bile leak, acute cholecystitis, biliary obstruction, and pancreatitis are discussed. Various classifications and complications that can arise with these conditions, as well as artifacts that may mimic pathology, are also included.

Multidetector CT of Surgically Proven Blunt Bowel and Mesenteric Injury

Blunt traumatic injury is one of the leading causes of morbidity and mortality in the United States. Unintentional injury represents the leading cause of death in the United States for all persons between the ages of 1 and 44 years. In the setting of blunt abdominal trauma, the reported rate of occurrence of bowel and mesenteric injuries ranges from 1% to 5%. Despite the relatively low rate of blunt bowel and mesenteric injury in patients with abdominal and pelvic trauma, delays in diagnosis are associated with increased rates of sepsis, a prolonged course in the intensive care unit, and increased mortality. During the past 2 decades, as multidetector computed tomography (CT) has emerged as an essential tool in emergency radiology, several direct and indirect imaging features have been identified that are associated with blunt bowel and mesenteric injury. The imaging findings in cases of blunt bowel and mesenteric injury can be subtle and may be seen in the setting of multiple complex injuries, such as multiple solid-organ injuries and spinal fractures. Familiarity with the various imaging features of blunt bowel and mesenteric injury, as well as an understanding of their clinical importance with regard to the care of the patient, is essential to making a timely diagnosis. Once radiologists are familiar with the spectrum of findings of blunt bowel and mesenteric injury, they will be able to make timely diagnoses that will lead to improved patient outcomes. ©RSNA, 2017.

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.

Acute Radiologic Manifestations of America’s Opioid Epidemic

The United States is in the midst of an opioid use epidemic, which has severe medical, social, and economic consequences. Addictions to and abuse of prescription and illicit opioids are increasing, and emergency department radiologists are increasingly being faced with the task of examining patients who present with opioid-related complications. These complications may be the result of direct drug toxicity or nonsterile injection of the drugs. Neurologic, musculoskeletal, cardiopulmonary, genitourinary, and gastrointestinal complications may be evident at diagnostic imaging in emergent settings. Heroin-induced leukoencephalopathy, cerebral septic emboli, mycotic arterial aneurysms, soft-tissue infections, and infective endocarditis are some of the conditions that patients may be found to have after they present to the emergency department. In this article, the above topics, including clinical features, pathophysiology, imaging findings, and treatment options, are reviewed. Recognizing the limitations of diagnostic imaging modalities that are available to radiologists is equally important, as some conditions can be successfully diagnosed after the initial triage-for example, transesophageal echocardiography can be performed to diagnose infective endocarditis. The emergency department radiologist may be responsible for identifying acute conditions, which can be life threatening. Some of the more common emergent opioid-related conditions and complications are reviewed, with specific emphasis on cases in which emergency department radiologists encounter conditions for which additional expertise is required. Becoming familiar with the conditions directly related to the current opioid epidemic will enable the diagnosis of these entities in a timely and accurate manner. ©RSNA, 2018.

Dual-Energy CT in Patients with an Acute Abdomen

Over the past two decades, multidetector computed tomography (CT) has become a powerful diagnostic tool in emergency medicine relied upon for a variety of conditions. More recently, the development of dual-energy CT technology has enhanced the ability of radiologists to diagnose and distinguish between a variety of conditions, improving accuracy and patient care. The ability to separate material density pairs allows for highly specific observations, and helps to avoid diagnostic pitfalls. Dual-energy CT has benefits in diagnosing conditions of the liver, gallbladder, kidneys, adrenals, pancreas, large and small bowel, as well as vascular structures. It also has benefits in diagnostic evaluation of patients in the setting of trauma. When its benefits are harnessed, dual-energy CT has the potential to significantly improve patient care in the emergency department.

Pelvic MRI after induction chemotherapy and before long-course chemoradiation therapy for rectal cancer: What are the imaging findings?

ObjectivesTo determine the appearance of rectal cancer on MRI after oxaliplatin-based chemotherapy (ICT) and make a preliminary assessment of MRI’s value in predicting response to total neoadjuvant treatment (TNT).MethodsIn this IRB-approved, HIPAA-compliant, retrospective study between 1 January 2010–20 October 2014, pre- and post-ICT tumour T2 volume, relative T2 signal intensity (rT2SI), node size, signal intensity and border characteristics were assessed in 63 patients (65 tumours) by three readers. The strength of association between the reference standard of histopathological percent tumour response and tumour volume change, rT2SI and lymph node characteristics was assessed with Spearman’s correlation coefficient and Wilcoxon’s rank sum test. Cox regression was used to assess association between DFS and radiological measures.ResultsChange in T2 volume was not associated with TNT response. Change in rT2SI showed correlation with TNT response for one reader only using selective regions of interest (ROIs) and borderline correlation with response using total volume ROI. There was a significant negative correlation between baseline and post-ICT node size and TNT response (r = -0.25, p = 0.05; r = -0.35, p = 0.005, readers 1 and 2, respectively). Both baseline and post-induction median node sizes were significantly smaller in complete responders (p = 0.03, 0.001; readers 1 and 2, respectively). Change in largest baseline node size and decrease in post-ICT node signal heterogeneity were associated with 100% tumour response (p = 0.04). Nodal sizes at baseline and post-ICT MRI correlated with DFS.ConclusionIn patients undergoing post-ICT MRI, tumour volume did not correlate with TNT response, but decreased lymph node sizes were significantly associated with complete response to TNT as well as DFS. Relative T2SI showed borderline correlation with TNT response.Key Points• MRI-based tumour volume after induction chemotherapy and before chemoradiotherapy did not correlate with overall tumour response at the end of all treatment.• Lymph node size after induction chemotherapy and before chemoradiotherapy was strongly associated with complete pathological response after all treatment.• Lymph node sizes at baseline and post-induction chemotherapy MRI correlated with disease-free survival.

FOLFCIS Treatment and Genomic Correlates of Response in Advanced Anal Squamous Cell Cancer

Micro‐Abstract In a series of 53 patients with advanced anal squamous cell cancer, we demonstrate that a modified 5‐fluorouracil and cisplatin schedule (FOLFCIS) with lower dose, more frequent administration of cisplatin is effective and well‐tolerated. This regimen should be considered a standard treatment option. Human papillomavirus‐negative anal squamous cell cancers were less sensitive to platinum‐based therapy and exhibited a distinct molecular profile. Background: Treatment of advanced anal squamous cell cancer (SCC) is usually with the combination of cisplatin and 5‐fluorouracil, which is associated with heterogeneous responses across patients and significant toxicity. We examined the safety and efficacy of a modified schedule, FOLFCIS (leucovorin, fluorouracil, and cisplatin), and performed an integrated clinical and genomic analysis of anal SCC. Patients and Methods: We reviewed all patients with advanced anal SCC receiving first‐line FOLFCIS chemotherapy – essentially a FOLFOX (leucovorin, fluorouracil, and oxaliplatin) schedule with cisplatin substituted for oxaliplatin – in our institution between 2007 and 2017, and performed deep sequencing to identify genomic markers of response and key genomic drivers. Results: Fifty‐three patients with advanced anal SCC (48 metastatic; 5 unresectable, locally advanced) received first‐line FOLFCIS during this period; all were platinum‐naive. The response rate was 48% (95% confidence interval [CI], 32.6%‐63%). With a median follow‐up of 41.6 months, progression‐free survival and overall survival were 7.1 months (95% CI, 4.4‐8.6 months) and 22.1 months (95% CI, 16.9‐28.1 months), respectively. Among all patients with advanced anal SCC that underwent sequencing during the study period, the most frequent genomic alterations consisted of chromosome 3q amplification (51%) and mutations in PIK3CA (29%) and KMT2D (22%). No genomic alteration correlated with response to platinum‐containing treatment. Although there were few cases, patients with human papillomavirus‐negative anal SCC did not appear to benefit from FOLFCIS, and all harbored distinct genomic profiles with TP53, TERT promoter, and CDKN2A mutations. Conclusions: FOLFCIS appears effective and safe as first‐line chemotherapy in patients with advanced anal SCC and represents an alternative treatment option for these patients.

Stereotactic core needle breast biopsy marker migration: An analysis of factors contributing to immediate marker migration

ObjectivesTo evaluate breast biopsy marker migration in stereotactic core needle biopsy procedures and identify contributing factors.MethodsThis retrospective study analyzed 268 stereotactic biopsy markers placed in 263 consecutive patients undergoing stereotactic biopsies using 9G vacuum-assisted devices from August 2010-July 2013. Mammograms were reviewed and factors contributing to marker migration were evaluated. Basic descriptive statistics were calculated and comparisons were performed based on radiographically-confirmed marker migration.ResultsOf the 268 placed stereotactic biopsy markers, 35 (13.1%) migrated ≥1 cm from their biopsy cavity. Range: 1–6 cm; mean (± SD): 2.35 ± 1.22 cm. Of the 35 migrated biopsy markers, 9 (25.7%) migrated ≥3.5 cm. Patient age, biopsy pathology, number of cores, and left versus right breast were not associated with migration status (P> 0.10). Global fatty breast density (P= 0.025) and biopsy in the inner region of breast (P = 0.031) were associated with marker migration. Superior biopsy approach (P= 0.025), locally heterogeneous breast density, and t-shaped biopsy markers (P= 0.035) were significant for no marker migration.ConclusionsMultiple factors were found to influence marker migration. An overall migration rate of 13% supports endeavors of research groups actively developing new biopsy marker designs for improved resistance to migration.Key Points• Breast biopsy marker migration is documented in 13% of 268 procedures.• Marker migration is affected by physical, biological, and pathological factors.• Breast density, marker shape, needle approach etc. affect migration.• Study demonstrates marker migration prevalence; marker design improvements are needed.