Special Report of the RSNA COVID-19 Task Force: The Short- and Long-term Financial Impact of the COVID-19 Pandemic on Private Radiology Practices.

The coronavirus disease 2019 (COVID-19) pandemic resulted in widespread disruption to the global economy, including demand for imaging services. The resulting reduction in demand for imaging services had an abrupt and substantial impact on private radiology practices, which are heavily dependent on examination volumes for practice revenues. The goal of this report is to describe the specific experiences of radiologists working in various types of private radiology practices during the initial peak of the COVID-19 pandemic.

Journal Club: Voice recognition dictation: analysis of report volume and use of the send-to-editor function.

Objective: The purpose of this study was to evaluate use of the send-to-editor function of a radiology voice recognition dictation system and compare study volumes of radiologists who self-edit with those of radiologists who send reports to the editor. Use of voice recognition shortcuts was also evaluated.

Materials And Methods: Voice recognition dictation systems were installed in a six-hospital system, including an 800-bed tertiary care center and five community hospitals, in 2002.

Acute ureteric calculus obstruction: unenhanced spiral CT versus HASTE MR urography and abdominal radiograph.

The aim of this study is to compare the performance of unenhanced spiral CT to the combination of HASTE MR urography (MRU) and plain abdominal radiography (KUB) in patients suspected of having acute calculus ureteric obstruction. 64 patients with suspected acute calculus ureteric obstruction were evaluated. The presence of perirenal fluid, presence and level of ureteric obstruction and calculi were assessed on both techniques.

Neurofibromatosis type 1: a diagnostic mimicker at CT.

Neurofibromatosis type 1 (NF1) is the most common of the phakomatoses and has a variety of localized or, more frequently, systemic manifestations throughout the thorax, abdomen, pelvis, and extremities. Classic computed tomographic (CT) findings in NF1 with thoracic involvement include small, well-defined subcutaneous neurofibromas, focal thoracic scoliosis, posterior vertebral scalloping, enlarged neural foramina, and characteristic rib abnormalities due to bone dysplasia or erosion from adjacent neurofibromas. However, more atypical manifestations are occasionally seen, and magnetic resonance (MR) imaging can be useful in equivocal cases.

Dural ectasia in the Marfan syndrome: MR and CT findings and criteria.

Purpose: To create criteria for detecting dural ectasia on MR or CT images in adult Marfan patients.

Methods: Images were analyzed using a workstation. Parameters that predicted dural ectasia were included in our criteria.

Osseous anatomy of the lumbosacral spine in Marfan syndrome.

Study Design: This study examines pedicle widths, laminar thicknesses, and scalloping values for lumbosacral spine elements in Marfan volunteers. Comparisons were made between these measurements and norms as well as measurements between Marfan patients with and without dural ectasia.

Objectives: To determine if the lumbosacral vertebral elements are altered in the patient with Marfan syndrome.

Local tumor recurrence following hepatic cryoablation: radiologic-histopathologic correlation in a rabbit model.

Purpose: To use radiologic-histopathologic correlation in an animal model to distinguish normal postoperative findings from evidence of residual tumor after cryoablation of malignant hepatic tumors.

Materials And Methods: Hepatic cryoablation was performed in 12 rabbits with VX2 tumors and in two healthy rabbits. Nonenhanced and dynamic contrast material-enhanced computed tomography (CT) and magnetic resonance (MR) imaging and power and color Doppler flow ultrasonography (US) were performed 7-8 days after cryoablation.

CT of primary cystic pancreatic neoplasms: can CT be used for patient triage and treatment?

Objective: The purpose of this study was to determine whether CT can be used to distinguish serous cystadenomas from mucinous cystadenomas or cystadenocarcinomas of the pancreas and play an enhanced role in patient triage and treatment.

Materials And Methods: A blinded retrospective analysis of CT scans from 50 patients with pathologically proven primary cystic pancreatic neoplasms was performed independently by three radiologists. Using classic CT criteria as reported in the literature, each tumor was categorized as definitely serous, mucinous, or indeterminate.

Contrast-enhanced MR angiography: the effects of k-space truncation on luminal representation in a carotid artery phantom model.

Using carotid bifurcation phantom models with different degrees of stenoses, we evaluated the accuracy of vessel lumen representation on MR images obtained from the inverse Fourier transform of different k-space percentages. Our results show that the lower thresholds of truncated k-space sampling are dictated by the severity of luminal narrowing. The defined thresholds may help improve efficiency of 3D MR imaging of the carotid arteries while maintaining adequate luminal representation.

Dural ectasia is associated with back pain in Marfan syndrome.

Study Design: A cross-sectional age- and sex-matched study comparing the prevalence and size of dural ectasia in two groups of patients with Marfan syndrome. Group I comprised patients with moderate to severe back pain and Group II comprised patients without back pain.

Objectives: To determine whether the presence and size of dural ectasia is associated with back pain in patients with Marfan syndrome.

1999 ARRS Executive Council Award. Contrast-enhanced CT of small hypovascular hepatic tumors: effect of lesion enhancement on conspicuity in rabbits. American Roentgen Ray Society.

Objective: The purpose of this study was to evaluate the effect of lesion enhancement on the conspicuity of small hypovascular hepatic tumors in an animal model.

Materials And Methods: Seven VX2 hepatic tumors in five rabbits were imaged. Dynamic contrast-enhanced CT was performed at a single level centered over the lesions at 5-sec intervals for 119 sec after injection of 2 ml/kg i.

Three-dimensional helical CT angiography in renal transplant recipients: a new problem-solving tool.

Objective: Our objective was to describe the use of three-dimensional helical CT angiography for the evaluation of renal transplant recipients presenting with hypertension, graft dysfunction, or both after transplantation by evaluating the native and transplanted renal arteries in a single examination.

Conclusion: Early results indicate that three-dimensional helical CT angiography of renal transplant recipients presenting with hypertension, graft dysfunction, or both after transplantation yields valuable information that can be used to guide further therapy.

CT angiography with volume rendering for quantifying vascular stenoses: in vitro validation of accuracy.

Objective: The purpose of this study was to evaluate the accuracy of CT angiography with volume rendering for quantifying vascular stenoses in vitro.

Materials And Methods: Vascular models with three degrees of stenosis (33%, 67%, and 83%) were imaged at three orientations to the axial plane (parallel, perpendicular, or 45 degrees ) using helical CT with 2-mm collimation and two pitches (1 or 2), two reconstruction intervals (1 or 2 mm), and two scan times (.75 or 1 sec).

Three-dimensional volume rendering of spiral CT data: theory and method.

Three-dimensional (3D) medical images of computed tomographic (CT) data sets can be generated with a variety of computer algorithms. The three most commonly used techniques are shaded surface display, maximum intensity projection, and, more recently, 3D volume rendering. Implementation of 3D volume rendering involves volume data management, which relates to operations including acquisition, resampling, and editing of the data set; rendering parameters including window width and level, opacity, brightness, and percentage classification; and image display, which comprises techniques such as "fly-through" and "fly-around," multiple-view display, obscured structure and shading depth cues, and kinetic and stereo depth cues.

Renal artery stenosis: CT angiography--comparison of real-time volume-rendering and maximum intensity projection algorithms.

Purpose: To compare results of helical computed tomographic (CT) angiography with real-time interactive volume rendering (VR) to CT angiography with maximum intensity projection (MIP) for the detection of renal artery stenosis.

Materials And Methods: Twenty-five patients underwent both conventional and CT angiography of the renal arteries. Images were blindly reviewed after rendering with MIP and VR algorithms.

Cryptococcoma of the sacrum.

Cryptococcoma of the sacrum was the initial presentation of systemic cryptococcosis in a patient on chronic steroid therapy for autoimmune hepatitis. The bone lesion was the only overt manifestation of systemic cryptococcal disease, which preceded other clinical manifestations and led to the subsequent diagnosis of systemic infection.

Neurovascular applications of CT angiography.

CT angiography, which has important advantages over both MR and ultrasound, is rapidly becoming an important modality for noninvasive evaluation of the neurovasculature. This article discusses CT angiography techniques for imaging the neurovasculature, including spiral acquisition protocols and image processing techniques, with a focus on the use of volume rendering for three-dimensional visualization. The clinical results for CT angiography of the cervical carotid arteries, intracranial aneurysms, arteriovenous malformations, and emerging work in the evaluation of acute stroke are reviewed.