Faculty Bibliography

PURPOSE/OBJECTIVE:To determine the yield of non-contrast multi-detector computed tomography (MDCT) of the abdomen and pelvis in diagnosing ureteral calculi as well as other alternative acute conditions in male vs in female adult patients presenting to the emergency department with new onset of symptoms. METHODS:Our institutional review board approved a retrospective review of the official reports of the non-contrast MDCT examinations of the abdomen and pelvis performed on adults (18 years and older) presenting to our emergency department with a suspected ureteral calculus from October 1, 2011 to October 30, 2013. Patients with recently documented ureteral calculi, known urinary tract infection, malignancy, and trauma were excluded from the study. From a total of 1097 non-contrast MDCT examinations of the abdomen and pelvis over the 2-year period, 400 randomly selected examinations were reviewed (approximately one-third of all the examinations). We compared the prevalence of ureteral calculi between the male and female population. P values and confidence intervals were determined using software Stata 14. Other acute intra-abdominal and intra-pelvic findings amenable to prompt medical care were also documented and analyzed separately. RESULTS:The mean patient age was 55.2 years, with a range of 19-90 years. This included 170 female (mean age 56.8 years) and 230 male patients (mean age 54.2 years). Ureteral calculi were detected in 170 (42.5%) of the patients [111 males (48%) and 59 females (34.7%)] with a prevalence which was statistically significantly higher in the male patients compared to in the female patients (P < 0.01, confidence level of 95% and CI of 13.2-13.4). An alternative diagnosis was made based on the MDCT findings in 49 patient cases (12.25 %), including 26 females (15.29%) and 23 males (10.00%). There was no statistically significant difference in alternative acute findings in male compared to in female patients (P > 0.05). This was with the exception of acute pyelonephritis, which was statistically significantly higher in the female patients (P < 0.01). CONCLUSION/CONCLUSIONS:The likelihood of making the diagnosis of a ureteral calculus on non-contrast MDCT of the abdomen and pelvis was statistically significantly higher in male patients compared with female patients presenting to our emergency department. However, there was no statistically significant difference in the alternative diagnoses, with the exception of pyelonephritis, which was more common in women.

Although a broad spectrum of entities can induce acute pathologic changes in the small bowel, there are relatively few imaging features that are characteristic of a specific diagnosis on the basis of CT findings. Specific clinical information, including time course and onset of disease, patient risk factors, and any recent pharmacologic or radiation therapy, is often instrumental in refining the differential diagnosis. A wide spectrum of disorders is reviewed in this article; however, given the breadth of disorders associated with the small bowel, neoplastic and infectious conditions affecting the small bowel that can manifest acutely are not specifically discussed. Vascular diseases that can affect the small bowel regionally or diffusely, including thromboembolic and hypoperfusion phenomena, as well as a spectrum of vasculitides, are reviewed. Iatrogenic causes of small bowel disorders are discussed, including angiotensin-converting enzyme inhibitor-induced angioedema, and chemotherapy- and radiation therapy-associated patterns of disease. Autoimmune and hereditary conditions that can affect the small bowel, including systemic lupus erythematosus and genetic C1 esterase inhibitor deficiency, respectively, are reviewed. ^©RSNA, 2018.

Obesity is a growing problem around the world, and radiology departments frequently encounter difficulties related to large patient size. Diagnosis and management of suspected venous thromboembolism, in particular deep venous thrombosis (DVT) and pulmonary embolism (PE), are challenging even in some lean patients, and can become even more complicated in the setting of obesity. Many obstacles must be overcome to obtain imaging examinations in obese patients with suspected PE and/or DVT, and to ensure that these examinations are of sufficient quality to diagnose or exclude thromboembolic disease, or to establish an alternative diagnosis. Equipment limitations and technical issues both need to be acknowledged and addressed. Table weight limits and scanner sizes that readily accommodate obese and even morbidly obese patients are not in place at many clinical sites. There are also issues with image quality, which can be substantially compromised. We discuss current understanding of the effects of patient size on imaging in general and, more specifically, on the imaging modalities used for the diagnosis and treatment of DVT and PE. Emphasis will be placed on the technical parameters and protocol nuances, including contrast dosing, which are necessary to refine and optimize images for the diagnosis of DVT and PE in obese patients, while remaining cognizant of radiation exposure. More research is necessary to develop consistent high-level evidence regarding protocols to guide radiologists, and to help them effectively utilize emerging technology.

OBJECTIVE:Common fetal anomalies of the kidneys and urinary tract encompass a complex spectrum of abnormalities that can be detected prenatally by ultrasound. Common fetal anomalies of the kidneys and urinary tract can affect amniotic fluid volume production with the development of oligohydramnios or anhydramnios, resulting in fetal pulmonary hypoplasia and, potentially, abnormal development of other fetal structures. CONCLUSION/CONCLUSIONS:We provide an overview of common fetal anomalies of the kidneys and urinary tract with an emphasis on sonographic patterns as well as pathologic and postnatal correlation, along with brief recommendations for postnatal management. Of note, we render an updated classification of fetal abnormalities of the kidneys and urinary tract based on the presence or absence of associated urinary tract dilation. In addition, we review the 2014 classification of urinary tract dilation based on the Linthicum multidisciplinary consensus panel.

The placenta plays a crucial role throughout pregnancy, and its importance may be overlooked during routine antenatal imaging evaluation. Detailed systematic assessment of the placenta at ultrasonography (US), the standard imaging examination during pregnancy, is important. Familiarity with the normal and abnormal imaging appearance of the placenta along with the multimodality and methodical approach for evaluation of its related abnormalities is necessary, so that radiologists can alert clinicians regarding appropriate prompt management decisions. This will potentially decrease fetal and maternal morbidity and mortality. This article reviews early placental formation and the expected imaging appearance of the placenta during pregnancy, as well as variations in its morphology. It also discusses various placental diseases and their potential clinical consequences. Placental pathologic conditions include abnormalities of placental size, cord insertion, placental and cord location, and placental adherence. Other conditions such as bleeding in and around the placenta, as well as trophoblastic and nontrophoblastic tumors of the placenta, are also discussed. US with Doppler imaging is the initial imaging modality of choice for placental evaluation. Magnetic resonance (MR) imaging is reserved for equivocal cases or when additional information is needed. Computed tomography (CT) has a limited role in evaluation of placental abnormalities because of the ionizing radiation exposure and the relatively limited assessment of the placenta; however, CT can provide important information in specific circumstances, particularly evaluation of trauma and staging of choriocarcinoma. This article also addresses recent techniques and updates in placental imaging, including elastography, diffusion-weighted MR imaging, and blood oxygen level-dependent (BOLD) MR imaging. These advanced imaging techniques may provide additional information in evaluation of abnormal placental adherence and new insights into placental pathophysiology in selected patients. Online supplemental material is available for this article.^©RSNA, 2017.

Ureteral injuries are uncommon in trauma patients, accounting for fewer than 1% of all injuries to the urinary tract. These uncommon, yet problematic, injuries can often be overlooked in the standard search pattern on abdominal and pelvic multi-detector CT (MDCT) images, as radiologists focus on more immediate life-threatening injuries. However, early diagnosis and management are vital to reduce potential morbidity. If there is a high clinical index of suspicion for ureteral injuries with penetrating or blunt trauma, or if there is suspected iatrogenic ureteral injury, delayed-phase/urographic-phase MDCT images are essential for confirming the diagnosis. Moreover, making the distinction between partial and complete ureteral transection is critical, as it will guide management. The aim of this pictorial review is to overview the key imaging findings in blunt and penetrating traumatic and iatrogenic injuries of the ureter, as well as to discuss the advantages and disadvantages of different imaging modalities for accurately and rapidly establishing or excluding the diagnosis of ureteral injuries, with an emphasis on MDCT. The potential causes of missed ureteral injuries will also be discussed.

The purpose of this article is to familiarize radiologists and clinicians with a subset of common and uncommon incidental findings on abdominal and pelvic computed tomography examinations, including hepatic, splenic, renal, adrenal, pancreatic, aortic/iliac arterial, gynecological, and a few other miscellaneous findings, with an emphasis on "incidentalomas" discovered in the emergency setting. In addition, we will review the complex problem of diagnosing such entities, and provide current management recommendations. Representative case examples, which we have encountered in our clinical practices, will be demonstrated.

BACKGROUND/PURPOSE/OBJECTIVE:Pediatric colonic volvulus is both rare and underreported. Existing literature consists only of case reports and small series. We present an analysis of cases (n=11) over 15 years at a single institution, focusing on workup and diagnosis. METHODS:This was an institutional review board approved single-institution retrospective chart review of 11 cases of large bowel volvulus occurring over 15 years (2000-2015). RESULTS:In our series, the most common presenting symptoms were abdominal pain and distention. Afflicted patients often had prior abdominal surgery, a neurodevelopmental disorder or chronic constipation. Of the imaging modalities utilized in the 11 patients studied, colonic volvulus was correctly diagnosed by barium enema in 100% of both cases, CT in 55.6% of cases and by plain radiography of the abdomen in only 22.2%of cases. Colonic volvulus was confirmed by laparotomy in all cases. The cecum (n=5) was the most often affected colonic segment, followed by the sigmoid (n=3). Operative treatment mainly consisted of resection (63.6%) and ostomy creation (36.4%). Colopexy was performed in 18.2% of cases. CONCLUSIONS:Plain abdominal radiography may be performed as an initial diagnostic study, however, it should be followed CT or air or contrast enema in children where there is high clinical suspicion and who do not have indications for immediate laparotomy. CT may be the most specific and useful test in diagnosis of colonic volvulus and has the added advantage of detection of complications including bowel ischemia. We demonstrate a range of diagnostic and therapeutic modalities for pediatric colonic volvulus. This underscores the need for further study to draft standard best practices for this life-threatening condition. LEVEL OF EVIDENCE/METHODS:Prognosis Study: Level IV. Study of a Diagnostic Test: Level III.