Acta radiologica open最新文献

Background: The impact of radiologists' characteristics has become a major focus of recent research. However, the markers of diagnostic efficacy and confidence in dense and non-dense breasts are poorly understood.

Purpose: This study aims to assess the relationship between radiologists' characteristics and diagnostic performance across dense and non-dense breasts.

Materials and methods: Radiologists specialising in breast imaging (n = 128) who had 0.5-40 (13±10.6) years of experience reading mammograms were recruited. Participants independently interpreted a test set containing 60 digital mammograms (40 normal and 20 abnormal) with similarly distributed breast densities. Diagnostic performance measures were analysed via Jamovi software (version 1.6.22).

Results: In dense breasts, breast-imaging fellowship completion significantly improved specificity (p = 0.004), location sensitivity (p = 0.01) and the area under the curve (AUC) of the receiver operating characteristic (p = 0.03). Only participation in BreastScreen reading significantly improved all performance metrics: specificity (p = 0.04), sensitivity (p = 0.005), location sensitivity (p < 0.001) and AUC (p < 0.001). Reading > 100 mammograms weekly significantly improved sensitivity (p = 0.03), location sensitivity (p = 0.001), and AUC (p = 0.03).In non-dense breasts, breast fellowship completion significantly improved sensitivity (p = 0.02), location sensitivity (p = 0.04) and AUC (p = 0.002). Participation in BreastScreen reading and reading > 100 mammograms weekly significantly improved only sensitivity (p = 0.002 and p = 0.003, respectively) and location sensitivity (p < 0.001 and p < 0.001, respectively).

Conclusion: Participating in screening programs, breast fellowships and reading > 100 mammograms weekly are important indicators of the diagnostic performance of radiologists across dense and non-dense breasts. In dense breasts, optimal performance resulted from participation in a breast screening program.

Background: Magnetic resonance imaging (MRI) biomarkers can diagnose and prognosticate kidney disease. Renal volume validation studies are however scarce, and measurements are limited by use of contrast agent or advanced post-processing.

Purpose: To validate a widely available non-contrast-enhanced MRI method for quantification of renal cortical and medullary volumes in pigs; investigate observer variability of cortical and medullary volumes in humans; and present reference values for renal cortical and medullary volumes in adolescents.

Materials and methods: Cortical and medullary volumes were quantified from transaxial in-vivo water-excited MR images in six pigs and 15 healthy adolescents (13-16years). Pig kidneys were excised, and renal cortex and medulla were separately quantified by the water displacement method. Both limits of agreement by the Bland-Altman method and reference ranges are presented as 2.5-97.5 percentiles.

Results: Agreement between MRI and ex-vivo quantification were -7 mL (-10-0 mL) for total parenchyma, -4 mL (-9-3 mL) for cortex, and -2 mL (-7-2 mL) for medulla. Intraobserver variability for pig and human kidneys were <5% for total parenchyma, cortex, and medulla. Interobserver variability for both pig and human kidneys were ≤4% for total parenchyma and cortex, and 6% and 12% for medulla. Reference ranges indexed for body surface area and sex were 54-103 mL/m² (boys) and 56-103 mL/m² (girls) for total parenchyma, 39-62 mL/m² and 36-68 mL/m² for cortex, and 16-45 mL/m² and 17-42 mL/m² for medulla.

Conclusion: The proposed widely available non-contrast-enhanced MRI method can quantify cortical and medullary renal volumes and can be directly implemented clinically.

Early detection of lung cancer recurrence on imaging is critical for better clinical prognosis. The 'enhancing nodule in post-radiation fibrosis sign' is an important sign which helps detect recurrent lung cancer early on CT chest.

Background: During the ongoing global SARS-CoV-2 pandemic, there is a high demand for quick and reliable methods for early identification of infected patients. Due to its widespread availability, chest-CT is commonly used to detect early pulmonary manifestations and for follow-ups.

Purpose: This study aims to analyze image quality and reproducibility of readings of scans using low-dose chest CT protocols in patients suspected of SARS-CoV-2 infection.

Materials and methods: Two radiologists retrospectively analyzed 100 low-dose chest CT scans of patients suspected of SARS-CoV-2 infection using two protocols on devices from two vendors regarding image quality based on a Likert scale. After 3 weeks, quality ratings were repeated to allow for analysis of intra-reader in addition to the inter-reader agreement. Furthermore, radiation dose and presence as well as distribution of radiological features were noted.

Results: The exams' effective radiation doses were in median in the submillisievert range (median of 0.53 mSv, IQR: 0.35 mSv). While most scans were rated as being of optimal quality, 38% of scans were scored as suboptimal, yet only one scan was non-diagnostic. Inter-reader and intra-reader reliability showed almost perfect agreement with Cohen's kappa of 0.82 and 0.87.

Conclusion: Overall, in this study, we present two protocols for submillisievert low-dose chest CT demonstrating appropriate or better image quality with almost perfect inter-reader and intra-reader agreement in patients suspected of SARS-CoV-2 infection.

Portal vein thrombosis is one of the most serious complications after liver transplantation. It is important to determine the age of the thrombus for management of portal vein thrombosis. We present a case report of histologically confirmed heterogenous fresh portal vein thrombus which was depicted heterogenous high signal intensity on magnetic resonance diffusion weighted imaging. The sequence may be a useful imaging tool for detecting fresh thrombus components in the portal vein thrombosis.

Background: The goals of neoadjuvant systemic therapy (NST) are to reduce tumor volume and to provide a prognostic indicator in assessing treatment response. Digital breast tomosynthesis (DBT) was developed and has increased interest in clinical settings due to its higher sensitivity for breast cancer detection compared to full-field digital mammography (FFDM).

Purpose: To evaluate the accuracy of DBT in assessing response to NST compared to FFDM, ultrasound (US), and magnetic resonance imaging (MRI) in breast cancer patients.

Material and methods: In this retrospective study, 95 stages II-III breast cancer patients undergoing NST and subsequent surgeries were enrolled. After NST, the longest diameter of residual tumor measured by DBT, FFDM, US, and MRI was compared with pathology. Agreements and correlations of tumor size were assessed, and the diagnostic performance for predicting pathologic complete response (pCR) was evaluated.

Results: Mean residual tumor size after NST was 19.9 mm for DBT, 18.7 mm for FFDM, 16.0 mm for US, and 18.4 mm for MRI, compared with 17.9 mm on pathology. DBT and MRI correlated better with pathology than that of FFDM and US. The ICC values were 0.85, 0.87, 0.74, and 0.77, respectively. Twenty-five patients (26.3%) achieved pCR after NST. For predicting pCR, area under the receiver operating characteristic (ROC) curve for DBT, FFDM, US, and MRI were 0.79, 0.66, 0.68, and 0.77, respectively.

Conclusion: DBT has good correlation with histopathology for measuring residual tumor size after NST. DBT was comparable to MRI in assessing tumor response after completion of NST.

Background: Dementia is one of the leading public health concerns as the world's population ages. Although Alzheimer's disease (AD) is the most common dementia diagnosis among older patients, some patients have additional behavioral symptoms. It is therefore important to provide an exact diagnosis, both to provide the best possible treatment for patients and to facilitate better understanding.

Purpose: To investigate whether magnetic resonance imaging (MRI) with fractional anisotropy (FA) can accurately find patients with behavioral symptoms within a group of AD patients.

Material and methods: Forty-five patients from the geriatric outpatient clinic were recruited consecutively to form a group of patients with AD and behavioral symptoms (AD + BS) and a control group of 50 patients with established AD. All patients had a full assessment for dementia to establish the diagnosis according to ICD-10. MRI included 3D anatomical recordings for morphometric measurements, DTI for fiber tracking, and quantitative assessment of regional white matter integrity. The DTI analyses included computing of the diffusion tensor and its derived FA index.

Results: We found a significant difference in FA values between the patient groups' frontal lobes. The FA was greater in the study group in both left (0.39 vs 0.09, p < 0.05) and right (0.40 vs 0.16, p < 0.05) frontal lobes.

Conclusion: MRI with FA will find damage in frontal tracts and may be used as a diagnostic tool and be considered a robust tool for the recognizing different types of dementia in the future.