Radiologic blind spots in hip and pelvic radiographs.

PURPOSE: The purpose of our study was to identify the locations at which hip and pelvic fractures are commonly missed on radiographs. METHODS: A retrospective study was performed at four non-Level 1 trauma center emergency departments. IRB approval was obtained. All emergency department hip or pelvic radiographs with subsequent CT performed within 48 h were identified from 2017 to 2022. Reports for each radiograph and CT were scored for the presence or the absence of fracture in the following locations: ilium, sacrum, superior pubic ramus, inferior pubic ramus, pubis, acetabulum, subcapital femoral, femoral neck, greater trochanter, lesser trochanter, intertrochanteric, and subtrochanteric. The CT report was used as the gold standard. The false-negative radiography cases were reviewed on a PACS workstation to determine whether the case had an "unexpected miss" of a fracture, a subtle fracture, radiographically occult fracture, or exam was limited by artifact. The percentage of missed fractures at each location was calculated. RESULTS: Nine hundred seventy-five radiography cases with subsequent CT were identified. One hundred forty-six cases did not meet entry criteria; therefore, 829 cases were analyzed further. Seventy-four percent of patients were female with age of 74 ± 16 (mean ± standard deviation) years (range 1-103). Three hundred fifty-two cases had at least one fracture, and many cases had multiple fractures. There were 68 false-negative cases. The most commonly missed fractures by percentage were pubis, ilium, and greater trochanter. The most common unexpectedly missed fractures were greater trochanter and femoral subcapital. CONCLUSION: A careful systematic evaluation of hip and pelvic radiographs, with particular attention to the pubis, ilium, greater trochanter, and subcapital region, may improve radiographic fracture detection and decrease delays in diagnosis.

Update on establishing and managing an overnight emergency radiology division.

Emergency department (ED) radiology divisions that serve to provide overnight attending coverage have become an increasingly common feature of radiology departments. The purpose of this article is to review the common ED radiology coverage models, describe desirable traits of emergency radiologists, and discuss workflow in the ED radiology setting. ED radiologists may be trained as ED radiologists or may develop the necessary skills and adopt the subspecialty. Choosing radiologists with the correct traits such as being a "night owl" and remaining calm under pressure and implementing an acceptable work schedule such as shift length of 9-10 h and a "one week on, two weeks off" schedule contribute to sustainability of the position. Strategies to address the unique stressors and workflow challenges of overnight emergency radiology coverage are also presented. Workflow facilitators including trainees, PAs, radiology assistants, and clerks all have roles to play in managing high case volumes and in making sure that the service is well staffed. Usage of artificial intelligence software is the latest technique to streamline workflow by identifying cases which should be prioritized on a busy worklist. Implementing such strategies will maintain quality of care for patients regardless of time of day as well as sustainability and quality of life for overnight emergency radiologists.

Non-traumatic hemoperitoneum in the ED setting: causes, characteristics, prevalence and sex differences.

PURPOSE: Prevalence and sex differences of non-traumatic hemoperitoneum in the Emergency Department has not been studied in the literature. METHODS: Following IRB approval, multiple keyword searches were used to identify all cases of hemoperitoneum over a 55-month period. Cases were reviewed to confirm and quantify the hemoperitoneum. Maximum attenuation was used to grade blood density. Medical records were reviewed to determine cause, interventions and outcomes in each patient. RESULTS: Of the 171 verified cases of non-traumatic hemoperitoneum, 76% of cases were in women. CT exams in women were positive for hemoperitoneum 0.25% of the time, while 0.13% were positive in men. Regarding size, 25.7% were large, 24.5% were moderate and 49.7% were small. Contrast-enhanced studies had HU values of 103 ± 19 (range 47-146) which were significantly higher than for non-enhanced studies with values of 82 ± 19 (range 43-121, p < 0.001). The most common cause of non-traumatic hemoperitoneum was ruptured ovarian cyst which was found in 58% of women (76 cases). Of these, 69 patients received observation, 6 patients underwent surgery and 1 patient received Vitamin K. For the 95 non-ovarian cyst cases, 65% patients were admitted and then discharged, 22% were discharged from the ED, 12% expired and 1% were transferred to a different hospital. Post-procedure hemorrhage was the second to most common cause in women (24/130 = 18%) and the most common etiology in men (14/41 = 34%). CONCLUSIONS: In women, ovarian cyst rupture was the most common etiology of hemoperitoneum. Post-procedure hemorrhage was second in women and the most common etiology in men. Although unusual causes of hemoperitoneum will be encountered, understanding the most common causes of hemoperitoneum can provide a reasonable starting point when attempting to determine the most likely etiology of hemoperitoneum in any individual patient.

Lower-extremity Arterial Thrombosis Associated with COVID-19 Is Characterized by Greater Thrombus Burden and Increased Rate of Amputation and Death.

Background During the peak of the coronavirus disease 2019 (COVID-19) pandemic, the authors noted an increase in positive lower-extremity CT angiography examinations in patients who presented with leg ischemia. The goal of this study was to determine whether lower-extremity arterial thrombosis was associated with COVID-19 and whether it was characterized by greater severity in these patients. Materials and Methods In this retrospective propensity score-matched study approved by the institutional review board, 16 patients who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and who underwent CT angiography of the lower extremities and 32 patients who tested negative for SARS-CoV-2 observed from January to April 2018, January to April 2019, and January to April 2020 were compared using three scoring systems: two systems including all vessels, with weighting in one system given to more proximal vessels and with weighting in the other system given to more distal vessels, and a third system in which only the common iliac through popliteal arteries were considered. Correlation with presenting symptoms and outcomes was computed. Fisher exact tests were used to compare patients who tested positive for COVID-19 with patients who tested negative for COVID-19 regarding the presence of clots and presenting symptoms. A Mantel-Haenszel test was used to associate outcome of death and/or amputation with COVID-19 adjusted according to history of peripheral vascular disease (PVD). Results Sixteen patients with confirmed COVID-19 (70 years ± 14 [standard deviation]; seven women) who underwent CT angiography and 32 propensity score-matched control patients (71 years ± 15; 16 women) were included. All patients with COVID-19 (100%, 95% confidence interval [CI]: 79%, 100%) had at least one thrombus, and only 69% of control patients (95% CI: 50%, 84%) had thrombi (P = .02). Ninety-four percent of patients with COVID-19 (95% CI: 70%, 99.8%) had proximal thrombi compared with 47% of control patients (95% CI: 29%, 65%) (P < .001). The mean thrombus score using any of the three scoring systems yielded greater scores in patients with COVID-19 (P < .001). Adjusted for history of PVD, death or limb amputation was more common in patients with COVID-19 (odds ratio = 25; 95% CI: 4.3, 147; P < .001). Patients with COVID-19 who presented with symptoms of leg ischemia only were more likely to avoid amputation or death than patients who also presented with pulmonary or systemic symptoms (P = .001). Conclusion Coronavirus disease 2019 is associated with lower-extremity arterial thrombosis characterized by a greater clot burden and a more dire prognosis. © RSNA, 2020.

No way out: Causes of duodenal and gastric outlet obstruction.

Upper gastrointestinal obstruction (UGIO), obstruction occurring at the level of the stomach or duodenum, represents only about 5% of bowel obstructions. As with other bowel obstructions, timely diagnosis is necessary to prevent complications including ischemia and death. Because the presenting symptoms of UGIO can be vague and nonspecific, the diagnosis may not be suspected clinically. The radiologist therefore provides immense value as the diagnosis and often the etiology of the obstruction can be ascertained through imaging. Here we present a simple classification scheme of etiologies of UGIO into congenital, malignant, infectious/inflammatory, and mechanical categories, and provide examples of the most common and some uncommon causes for each category. We highlight that several of the congenital etiologies of UGIO can present at any age, including adulthood, and therefore it is important for the radiologist to keep these diagnoses in mind when reviewing cases of UGIO. For each etiology, we provide typical imaging strategies that are used for diagnosis as well as key points regarding the diagnosis.

The Emergency Radiology Dashboard: Facilitating Workflow With Realtime Data.

Emergency radiology imaging volume varies widely due to predictable (eg, day of the week) and unpredictable factors. This can lead to inefficient or insufficient staffing of radiologists, suboptimal workflow and poor trainee education. In collaboration with the radiology IT division we created and implemented a 2-tiered real-time dashboard to facilitate operational workflow. This allowed us to track overall emergency department patient census, ordered but not yet performed imaging studies, and performed but unread imaging studies. The capability of clicking to obtain information on specific studies was also incorporated. We describe our experience of how this information has improved our workflow, staffing, and trainee education.

CT of the Neck: Image Analysis and Reporting in the Emergency Setting.

Interpreting findings seen at CT of the neck is challenging owing to the complex and nuanced anatomy of the neck, which contains multiple organ systems in a relatively small area. In the emergency department setting, CT is performed to investigate acute infectious or inflammatory symptoms and chronic processes. With few exceptions, neck CT should be performed with intravenous contrast material, which accentuates abnormally enhancing phlegmonous and neoplastic tissues and can be used to delineate any abscesses or necrotic areas. As part of the evaluation, the vascular structures and aerodigestive tract must be scrutinized, particularly for patency. Furthermore, although the patient may present because of symptoms that suggest non-life-threatening conditions involving structures such as the teeth or salivary glands, there may be serious implications for other areas, such as the orbits, brain, and spinal cord, that also may be revealed at the examination. With a focus on the emergency setting, the authors propose using an approach to interpreting neck CT findings whereby 12 areas are systematically evaluated and reported on: the cutaneous and subcutaneous soft tissues, aerodigestive tract and adjacent soft tissues, teeth and periodontal tissues, thyroid gland, salivary glands, lymph nodes, vascular structures, bony airspaces, cervical spine, orbits and imaged brain, lung apices, and superior mediastinum. The use of a systematic approach to interpreting neck CT findings is essential for identifying all salient findings, recognizing and synthesizing the implications of these findings to formulate the correct diagnosis, and reporting the findings and impressions in a complete, clear, and logical manner.Online supplemental material is available for this article.©RSNA, 2019.

New CT-based diagnoses of torso cancer is low in the emergency department setting.

PURPOSE: The incidence of new CT-based torso cancer diagnoses and the most commonly diagnosed cancer types in the emergency department (ED) setting are unknown. The purpose of our study was to determine the incidence and types of new CT-based torso cancer diagnoses in the ED. METHODS: A total of 19,496 CT reports including all or parts of the torso from 2017 were searched for the keywords: "mass", "tumor", "neoplasm", "malignancy", or "cancer". Each report and corresponding medical record was evaluated for presence of a new cancer. Cases were scored as no cancer, subcentimeter lung nodule, known cancer, new cancer, or suspicious, but unconfirmed for new cancer. Each mass was characterized as symptom-related or incidental. RESULTS: At least one keyword was found in 2086 reports. Of these 706, 126 and 905 were known cancer cases, subcentimeter lung nodules, and non-cancerous cases, respectively. There were 251 confirmed new cancers and 98 suspicious cases which lacked adequate diagnostic workup. Depending on whether only definite or definite and suspicious cases were included together, the number of new cancer cases per 100 torso CT exams was 1.3 or 1.8, respectively. Gastrointestinal, lung, pancreaticobiliary, urinary, and gynecologic cancers were most common. Only 58 of the confirmed cases (23%) were deemed as incidental findings. CONCLUSION: CT-diagnosis of new torso cancers was uncommon in our setting. Still, while extensive knowledge of cancer staging may not be necessary for ED radiologists, knowledge of the most common types of cancer including gastrointestinal, lung, pancreaticobiliary, urinary, and gynecologic cancers may improve sensitivity for these diagnoses and may expedite appropriate referrals for the newly diagnosed patients.

Implantable Electronic Stimulation Devices from Head to Sacrum: Imaging Features and Functions.

Electronic stimulation devices are implanted in various locations in the body to decrease pain, modulate nerve function, or stimulate various end organs. The authors describe these devices using a craniocaudal approach, first describing deep brain stimulation (DBS) devices and ending with sacral nerve stimulation (SNS) devices. The radiology-relevant background information for each device and its imaging appearance are also described. These devices have a common design theme and include the following components: (a) a pulse generator that houses the battery and control electronics, (b) an insulated lead or wire that conveys signals to the last component, which is (c) an electrode that contacts the end organ and senses and/or acts on the end organ. DBS electrodes are inserted into various deep gray nuclei, most commonly to treat the symptoms of movement disorders. Occipital, trigeminal, and spinal nerve stimulation devices are used as second-line therapy to control craniofacial or back pain. For cardiac devices, the authors describe two newer devices, the subcutaneous implantable cardioverter defibrillator and the leadless pacemaker, both of which avoid complications related to having leads threaded through the venous system. Diaphragmatic stimulation devices stimulate the phrenic nerve to restore diaphragmatic movement. Gastric electrical stimulation devices act on various parts of the stomach for the treatment of gastroparesis or obesity. Finally, SNS devices are used to modulate urinary and defecatory functions. Common complications diagnosed at imaging include infection, hematoma, lead migration, and lead breakage. Understanding the components, normal function, and normal imaging appearance of each device allows the radiologist to identify complications. ©RSNA, 2019.

Imaging of Lumen-Apposing Metal Stents in Abdominopelvic Applications.

OBJECTIVE. Lumen-apposing metal stents (LAMS) are increasingly being used for abdominopelvic drainage applications. The purpose of this article is to describe the normal imaging appearance of these stents and the radiologic findings in stent-related complications. CONCLUSION. LAMS facilitate effective drainage, but the complications include bleeding, pseudoaneurysm formation, stent occlusion, and stent migration.

Implementing a Software Solution Across Multiple Ultrasound Vendors to Auto-fill Reports with Measurement Values.

Reliable transmission of ultrasound measurements into radiology reports is fraught with potential sources of error. In a conventional workflow, measurements are either written by hand on worksheets and/or dictated from worksheets or the images themselves into the radiology report. Valuable physician time is spent dictating, checking, and editing these values and this process is error-prone. Our approach was to use a transfer-software application to auto-populate measurements, with a goal of achieving >90% utilization rate by both technologists and radiologists. Implementation involved creating measurement fields for each measurement on each ultrasound unit of our multisite academic department. These fields were then mapped in both the transfer-software and the dictation software, to set up a 1:1:1 correspondence for each field. As a result, each measurement acquired by the technologist would automatically populate the radiology report within the dictation software. We created and mapped 128 fields for 39 exam templates. After implementation, technologist utilization rate was 86%-96% and overall radiologist utilization rate was 92%-93%. Radiology resident utilization rate was highest, at 95%-96%. We provide a guide for implementation and lessons learned.

Diagnostic yield of head CT in pediatric emergency department patients with acute psychosis or hallucinations.

BACKGROUND: Children presenting to the emergency department with acute psychosis or hallucinations sometimes undergo a head CT to evaluate for a causative lesion. The diagnostic yield of head CT in this scenario has not been reported. OBJECTIVE: To determine the yield for head CT in children with acute psychosis or hallucinations. MATERIALS AND METHODS: We retrospectively searched the radiology report database over a 7.5-year period for head CT reports for pediatric emergency department patients using the following keywords: hallucination, psychosis, psychotic or "hearing voices." All reports were categorized as normal or abnormal, and we reviewed and categorized the abnormal cases. We calculated the 95% confidence interval for abnormal CTs using the method of Clopper and Pearson. RESULTS: We identified 397 pediatric emergency department head CTs. We excluded one non-diagnostic exam. We excluded 34 additional cases (which were all normal) because of clinical indications that might have independently triggered a head CT. Of the remaining 362 cases, 12 reports described abnormalities or variants and we reviewed them individually. Based on consensus review, four were normal, four had congenital malformations, three had encephalomalacia versus demyelination and one demonstrated cortical atrophy. There were no cases with actionable findings such as mass, hemorrhage, infection or hydrocephalus. The 95% confidence interval for a CT demonstrating causative findings was calculated at 0-0.82%. CONCLUSION: In the absence of concerning factors such as focal neurological deficits, evidence of central nervous system infection, trauma or headache, routine screening head CT might not be warranted in children presenting with acute psychosis or hallucinations.

Causes of pneumocephalus and when to be concerned about it.

Intracranial gas is commonly detected on neuroimaging. The recognition of this finding can at first blush be unsettling. Being able to localize this gas to a specific compartment: intraarterial, intravenous, intraparenchymal, subdural, epidural, subarachnoid and intraventricular, is the first step in determining the importance of the gas. Determination of the route of entry: through the skull, extension from a paranasal sinus or the mastoid air cells, via the spine, or trans-vascular, is the other important factor in determining potential consequences. Understanding these parameters allows for a confident determination of etiology. More importantly, it generally provides guidance as to what must be done: either to disregard (e.g., subarachnoid gas following lumbar puncture and intravenous gas following IV placement), obtain follow-up (e.g., postoperative gas), or administer emergent treatment (e.g., intraarterial gas and epidural abscess). In this review, we use gas location and route of entry to classify the various causes of pneumocephalus and provide examples of each of these etiologies.

Radiology-Pathology Conference: Reviving the Art of Oral Case Presentation in Residency.

RATIONALE AND OBJECTIVES: To improve resident oral case communication and preparatory skills by providing residents an opportunity to prepare for and conduct a new interdisciplinary Radiology-Pathology (Rad-Path) conference series. MATERIALS AND METHODS: To assess whether conference goals were being achieved, we surveyed trainees and attendings in the radiology and pathology departments. Percentages were examined for each variable. Mann-Whitney U test for ordinal variable significance was applied to determine statistical significance between radiology trainee and attending survey responses. RESULTS: Most surveyed radiology trainees (57.1%) strongly agreed or agreed with: "I wish I felt more comfortable with oral presentations." Sixty-five percent of radiology attendings (34 of 52) either agreed or strongly agreed that the residents should be more comfortable with oral case presentations. Of resident Rad-Path conference presenters, 69% (9 of 13) either agreed or strongly agreed that the conference improved their confidence and/or ability to present case information orally. Of responders who attended at least one Rad-Path conference in person, 83% of residents (19/23) and 61% (17/28) of attendings agreed or strongly agreed that the conference improved their ability to formulate a differential diagnosis. Using the Mann-Whitney U test, no significant difference was found between radiology trainees and attendings' responses. CONCLUSIONS: Our Rad-Path correlation conference was specifically designed and structured to provide residents with focused experience in formal oral case preparation and presentation. We consider our conference a success, with 69% of resident presenters reporting that the Rad-Path conference improved their confidence and/or ability to present case information orally.

MRI usage in a pediatric emergency department: an analysis of usage and usage trends over 5 years.

BACKGROUND: Magnetic resonance imaging (MRI) usage has anecdotally increased due to the principles of ALARA and the desire to Image Gently. Aside from a single abstract in the emergency medicine literature, pediatric emergency department MRI usage has not been described. OBJECIVE: Our objective was to determine whether MRI use is indeed increasing at a high-volume urban pediatric emergency department with 24/7 MRI availability. Also, we sought to determine which exams, time periods and demographics influenced the trend. MATERIALS AND METHODS: Institutional Review Board exemption was obtained. Emergency department patient visit and exam data were obtained from the hospital database for the 2011-2015 time period. MRI usage data were normalized using emergency department patient visit data to determine usage rates. The z-test was used to compare MRI use by gender. The chi-square test was used to test for trends in MRI usage during the study period and in patient age. MRI usage for each hour and each weekday were tabulated to determine peak and trough usage times. RESULTS: MRI usage rate per emergency department patient visit was 0.36%. Headache, pain and rule-out appendicitis were the most common indications for neuroradiology, musculoskeletal and trunk exams, respectively. Usage in female patients was significantly greater than in males (0.42% vs. 0.29%, respectively, P<0.001). Usage significantly increased during the 5-year period (P<0.001). Use significantly increased from age 3 to 17 (0.011% to 1.1%, respectively, P<0.001). Sixty percent of exams were performed after-hours, the highest volume during the 10 p.m. hour and lowest between 4 a.m. and 9 a.m. MRI use was highest on Thursdays and lowest on Sundays (MRI on 0.45% and 0.22% of patients, respectively). CONCLUSION: MRI use in children increased during the study period, most notably in females, on weekdays and after-hours.