Even non-expert radiologists report chronic thromboembolic pulmonary hypertension (CTEPH) on CT pulmonary angiography with high sensitivity and almost perfect agreement.

OBJECTIVES: To assess the diagnostic performance and interobserver agreement of CT pulmonary angiography (CTPA) in the detection of chronic thromboembolic pulmonary hypertension (CTEPH) and its features among radiologists of different levels of experience. MATERIALS AND METHODS: In this retrospective, single-center, single-blinded study, three radiologists with different levels of experience in CT imaging (R1:15 years, R2:6 years, and R3:3 years) evaluated CTPA of 51 patients ultimately diagnosed with CTEPH (European Society of Cardiology guidelines) and 49 patients without CTEPH in random order to assess the presence of CTEPH, its features in the pulmonary artery tree, proximal level of involvement, bronchial artery hypertrophy, mosaic perfusion, and right heart overload. RESULTS: CTPAs of 51 patients with CTEPH (median age, 66 years (IQR 56-72), 28 men) and 49 patients without CTEPH (median age, 65 years (IQR 50-74), 25 men) were evaluated. The sensitivity and specificity for the detection of CTEPH was 100% (all radiologists) and 100% (R1), 96% (R2), and 96% (R3) with almost perfect agreement (κ = 0.95). The sensitivity and specificity for detecting CTEPH by mosaic perfusion would be 89% (95%CI 83-93%) and 81% (74-87%). The level of pulmonary artery involvement was reported with moderate agreement (κ = 0.54, 95%CI 0.40-0.65). Substantial agreement was found in the evaluation of mosaic attenuation (κ = 0.75, 95%CI 0.64-0.84), right heart overload (κ = 0.68, 95%CI 0.56-0.79), and bronchial artery hypertrophy (0.71, 95%CI 0.59-0.82) which were the best predictors of CTEPH (p < 0.0001). CONCLUSIONS: CTPA has high sensitivity and specificity in detecting CTEPH and almost perfect agreement among radiologists of different levels of expertise. CLINICAL RELEVANCE: CT pulmonary angiography can be used as a first-line imaging modality in patients with suspected chronic thromboembolic pulmonary hypertension (CTEPH) even when interpreted by non-CTEPH experts. KEY POINTS: • CT pulmonary angiography has high sensitivity and specificity in detecting chronic thromboembolic pulmonary hypertension (CTEPH) and almost perfect interobserver agreement among radiologists of different levels of expertise. • Substantial agreement exists in the assessment of mosaic attenuation, right heart overload, and bronchial artery hypertrophy, which are the best predictors of CTEPH.

Both decreased and increased grey-to-white matter attenuation ratio in the putamen and caudate on early head computed tomography differentiate patients with favorable and unfavorable outcomes after prolonged cardiac arrest-secondary analysis of the Prague OHCA study.

Background: Neurological damage remains the leading cause of death in cardiac arrest victims with early neuroprognostication being the cornerstone of the decision-making process to continue or discontinue advanced treatments. In this study, we aimed to find markers of favorable and unfavorable outcome on early brain computed tomography (CT) in patients after prolonged out-of-hospital cardiac arrest (OHCA) treated both by conventional and extracorporeal cardiopulmonary resuscitation (ECPR). Methods: In a secondary analysis of the Prague OHCA study, patients who underwent brain CT within 36 hours after cardiac arrest were identified. Qualitative findings (brain edema, hemorrhage) and quantitative measurements [attenuation of grey matter structures and grey-to-white matter attenuation ratio (GWR)] between patients with cerebral performance category (CPC) of 1-2 (favorable outcome) and 3-5 (unfavorable outcome) within 180 days after the event were compared. Results: In 45 eligible patients, intracranial edema (n=16, 50%) was present in patients with CPC 3-5 only (n=32, 71%). Attenuation of brain structures and GWR did not differ between patients with favorable and unfavorable outcomes. However, the GWR in the caudate and putamen of most CPC 1-2 patients was within a narrow range of values (1.18 to 1.30 and 1.20 to 1.33) that separated patients with CPC 1-2 from CPC 3-5 with a sensitivity of 78% and 66% a specificity of 85% and 100%, and area under the curve （AUC） of 0.86 (P=0.0001) and 0.77 (P=0.0053), respectively. Patients treated by ECPR had lower attenuation in the centrum semiovale (28.3±2.7) compared to those who were not (31.0±2.8, P=0.003). The most common causes of death in CPC 3-5 patients were brain death in 13 (41%) patients, multiorgan failure in 12 (38%), and cardiac rearrest in 4 (13%). Conclusions: Both decreased and increased grey-to-white matter differentiation in the putamen and caudate on early non-contrast brain CT after prolonged OHCA indicate poor neurological outcome within 180 days after cardiac arrest.

The diagnostic performance of whole-body MRI in the staging of lymphomas in adult patients compared to PET/CT and enhanced reference standard-systematic review and meta-analysis.

BACKGROUND: Morphology highlighted by diffusion weighted imaging (DWI) is the basis of whole-body MRI (wbMRI). The aim of this study was to analyze current knowledge on the diagnostic performance of wbMRI in the pretreatment staging of patients with lymphoma. METHODS: A search for original articles reporting the diagnostic performance (sensitivity, specificity) of pretreatment (first staging or staging in relapsed patients after complete remission) wbMRI in nodal and extranodal involvement by extracranial lymphoma and the agreement of stage by the Cotswolds-modified Ann Arbor classification in adult patients compared to the reference standard (PET/CT or enhanced reference standard) was conducted in PubMed, EMBASE, Cochrane Library, ClinicalTrials.gov. RESULTS: Altogether 15 studies with 519 patients were included in the meta-analysis. The pooled sensitivity and specificity for nodal involvement were 0.93 (95% CI: 0.90 to 0.96) and 0.99 (95% CI: 0.98 to 1.00). For nodal staging, most studies used the size criterion of 10 mm in the short diameter (n=10) and the absence of prominent fatty hilum (n=4). Restricted diffusion on diffusion-weighted imaging as a sign of nodal involvement was either not used (n=5), used for detection (n=4), semi-quantitatively (n=4), or quantitatively (n=1). Only one study (7) relied solely on restricted diffusion as the main criterion for nodal involvement. The pooled sensitivity and specificity for extranodal involvement were 0.89 (95% CI: 0.79 to 0.98) and 0.99 (95% CI: 0.99 to 1.00). Seven studies considered diffuse splenic involvement when its long or vertical axis was greater than 13 cm regardless of the patient's physiognomy. The pooled agreement in staging (Cohen's kappa) was almost perfect (0.90, 95% CI: 0.84 to 0.95). DISCUSSION: The sensitivity and specificity of wbMRI in the assessment of the nodal and extranodal involvement by lymphoma is high. The agreement of wbMRI with the reference standard is almost perfect.

Pancreatic Injury in Patients with SARS-Cov-2 (COVID-19) Infection: A Retrospective Analysis of CT Findings.

OBJECTIVE: To determine the association between COVID-19 infection and peripancreatic changes on CT as a sign of acute pancreatic injury. METHODS: Retrospective analysis of CT examinations in patients with confirmed COVID-19 infection yielded 103 instances. An age- and gender-matched cohort of patients without COVID-19 was found. CT examinations were evaluated for peripancreatic stranding or edema, fluid collection, or necrosis, without any other explanation. Depicted pulmonary parenchyma was evaluated for possible COVID-19-related changes. Clinical and laboratory data were retrieved from the clinical database. RESULTS: Peripancreatic fat stranding (n = 8) or fluid collection (n = 2) without any other cause was found in 10 (10%) patients. Abdominal complaints were reported in 4 (40%) patients. Elevated serum amylase or lipase levels were documented in 5 (50%) patients who also satisfied the diagnostic criteria for acute pancreatitis. From the study sample of 103 patients with COVID-19, pulmonary parenchyma was depicted in 102 (99%), and from these, 57 (55%) had an evidence of pulmonary changes compatible with COVID-19 pneumonia. This proportion was not significantly different between patients with and without peripancreatic changes (p = 0.35). In the matched cohort, we found peripancreatic changes in 2 (2%, p = 0.033) patients. Patients with pancreatic injury and elevated amylase levels were more likely to require orotracheal intubation (35% vs. 12%, p = 0.021). CONCLUSIONS: We showed that the prevalence of peripancreatic stranding or fluid collection is higher in patients diagnosed with COVID-19 infection compared to an age- and gender-matched cohort. Patients with pancreatic injury and elevated amylase levels are more likely to require orotracheal intubation. Our findings corroborate the link between COVID-19 infection and pancreatic injury from the perspective of imaging.

A bimodal pattern of the onset of COVID-19 related acute pancreatitis supports both the cytotoxic and immune-related pathogenesis - a systematic review.

OBJECTIVES: To review clinical and laboratory findings in patients with SARS-Cov-2 (COVID-19) related acute pancreatitis. METHODS: This systematic review was based on a database search for articles of COVID-19 related acute pancreatitis in adult patients with confirmed COVID-19 infection that included age, gender, presenting symptoms, the onset of symptoms, laboratory values, imaging findings and exclusion of common causes of pancreatitis. RESULTS: Altogether 35 articles comprising 37 patients were included. Acute pancreatitis was the first presentation of COVID-19 in 43% of patients, concurrent with general or respiratory symptoms in 14% of patients or delayed after general or pulmonary symptoms by an average of 10 ± 5 d (range, 1 - 19 d) in 43% of patients. Serum amylase and lipase levels were elevated in 87% and 100% of patients. In 50% and 84%, amylase and lipase levels exceeded three-fold the upper normal limit. Pancreatic necrosis was reported in 6% of patients and in 12% of patients, the pancreas appeared normal. Three patients died. CONCLUSIONS: We conclude that the bi-modal pattern of the onset of symptoms supports both the cytotoxic and the immune-related pathogenesis of the pancreatic injury. Acute pancreatitis may be the first symptom of COVID-19 infection. Necrosis of the pancreas is rare.

Early detection of lung cancer in Czech high-risk asymptomatic individuals (ELEGANCE): A study protocol.

BACKGROUND: Lung cancer screening in high-risk population increases the proportion of patients diagnosed at a resectable stage. AIMS: To optimize the selection criteria and quality indicators for lung cancer screening by low-dose CT (LDCT) in the Czech population of high-risk individuals. To compare the influence of screening on the stage of lung cancer at the time of the diagnosis with the stage distribution in an unscreened population. To estimate the impact on life-years lost according to the stage-specific cancer survival and stage distribution in the screened population. To calculate the cost-effectiveness of the screening program. METHODS: Based on the evidence from large national trials - the National Lung Screening Trial in the USA (NLST), the NELSON study, the recent recommendations of the Fleischner society, the American College of Radiology, and I-ELCAP action group, we developed a protocol for a single-arm prospective study in the Czech Republic for the screening of high-risk asymptomatic individuals. The study commenced in August 2020. RESULTS: The inclusion criteria are: age 55 to 74 years; smoking: ≥30 pack-years; smoker or ex-smoker <15 years; performance status (0-1). The screening timepoints are at baseline and 1 year. The LDCT acquisition has a target CTDIvol ≤0.5mGy and effective dose ≤0.2mSv for a standard-size patient. The interpretation of findings is primarily based on nodule volumetry, volume doubling time (and related risk of malignancy). The management includes follow-up LDCT, contrast enhanced CT, PET/CT, tissue sampling. The primary outcome is the number of cancers detected at a resectable stage, secondary outcomes include the average cost per diagnosis of lung cancer, the number, cost, complications of secondary examinations, and the number of potentially important secondary findings. CONCLUSIONS: A study protocol for early detection of lung cancer in Czech high-risk asymptomatic individuals (ELEGANCE) study using LDCT has been described.