Multireader Evaluation of Radiologist Performance for COVID-19 Detection on Emergency Department Chest Radiographs

Background Chest radiographs (CXR) are frequently used as a screening tool for patients with suspected COVID-19 infection pending reverse transcriptase polymerase chain reaction (RT-PCR) results, despite recommendations against this. We evaluated radiologist performance for COVID 19 diagnosis on CXR at the time of patient presentation in the Emergency Department (ED). Materials and Methods We extracted RT PCR results, clinical history, and CXRs of all patients from a single institution between March and June 2020. 984 RT PCR positive and 1043 RT-PCR negative radiographs were reviewed by 10 emergency radiologists from 4 academic centers. 100 cases were read by all radiologists and 1927 cases by 2 radiologists. Each radiologist chose the single best label per case: Normal, COVID 19, Other Infectious, Other Noninfectious, Non diagnostic, and Endotracheal Tube. Cases labeled with endotracheal tube or non-diagnostic were excluded. Remaining cases were analyzed for label distribution, clinical history, and inter-reader agreement. Results 1727 radiographs (732 RT PCR positive, 995 RT PCR negative) were included from 1,594 patients (51.2% male, 48.8% female, age 59 +/- 19 years). For 89 cases read by all readers, there was poor agreement for RT PCR positive (Fleiss Score 0.36) and negative (Fleiss Score 0.46) exams. Agreement between two readers on 1,638 cases was 54.2% (373/688) for RT-PCR positive cases and 71.4% (679/950) for negative cases. Agreement was highest for RT PCR negative cases labeled as Normal (50.4%, n= 479). Reader performance did not improve with clinical history or time between CXR and RT-PCR result. Conclusion At the time of presentation to the emergency department, emergency radiologist performance is non-specific for diagnosing COVID 19.

Lower Urinary Tract Injuries: A Guide for the Emergency Radiologist

Traumatic lower urinary tract injuries are uncommon and mainly occur in patients with severe trauma and multiple abdominopelvic injuries. In the presence of other substantial injuries, bladder and urethral injuries may be overlooked and cause significant morbidity and mortality. Therefore, it is important that radiologists are familiar with mechanisms and injuries that are high risk for bladder and urethral trauma. We review the imaging findings associated with these injuries and the appropriate modalities and techniques to further evaluate the patient and accurately diagnose these injuries. Computed tomography cystography and conventional retrograde urethrography are effective tools in identifying injuries to the lower urinary tract and play a crucial role in patient care and prognosis.