Computational analysis of variability and uncertainty in the clinical reference on magnetic resonance imaging radiomics: modelling and performance.

To conduct a computational investigation to explore the influence of clinical reference uncertainty on magnetic resonance imaging (MRI) radiomics feature selection, modelling, and performance. This study used two sets of publicly available prostate cancer MRI = radiomics data (Dataset 1: n = 260; Dataset 2: n = 100) with Gleason score clinical references. Each dataset was divided into training and holdout testing datasets at a ratio of 7:3 and analysed independently.

Evaluation of the Reliability and the Performance of Magnetic Resonance Imaging Radiomics in the Presence of Randomly Generated Irrelevant Features for Prostate Cancer.

Radiomics has the potential to aid prostate cancer (PC) diagnoses and prediction by analyzing and modeling quantitative features extracted from clinical imaging. However, its reliability has been a concern, possibly due to its high-dimensional nature. This study aims to quantitatively investigate the impact of randomly generated irrelevant features on MRI radiomics feature selection, modeling, and performance by progressively adding randomly generated features.

Striatal dopamine synthesis capacity and its association with negative symptoms upon resolution of positive symptoms in first-episode schizophrenia and delusional disorder.

Rationale: How striatal dopamine synthesis capacity (DSC) contributes to the pathogenesis of negative symptoms in first-episode schizophrenia (SZ) and delusional disorder (DD) has seldom been explored. As negative symptoms during active psychotic episodes can be complicated by secondary influences, such as positive symptoms, longitudinal investigations may help to clarify the relationship between striatal DSC and negative symptoms and differentiate between primary and secondary negative symptoms.

Objective: A longitudinal study was conducted to examine whether baseline striatal DSC would be related to negative symptoms at 3 months in first-episode SZ and DD patients.

3D-T2W-TSE radiotherapy treatment planning MRI using compressed sensing acceleration for prostate cancer: Image quality and delineation value.

Purpose: To assess the image quality and delineation value of compressed sensing (CS)-accelerated 3D T2W turbo-spin-echo (TSE) sequence for radiotherapy treatment planning (RTP) of prostate cancer.

Methods: An optimized CS-accelerated 3D-T2W-TSE was determined by volunteer imaging and applied for clinical RTP-MRI. This optimized CS-accelerated planning MRI and the standardized adaptive MRI acquired at 1.

Radiomics feature reliability assessed by intraclass correlation coefficient: a systematic review.

Radiomics research is rapidly growing in recent years, but more concerns on radiomics reliability are also raised. This review attempts to update and overview the current status of radiomics reliability research in the ever expanding medical literature from the perspective of a single reliability metric of intraclass correlation coefficient (ICC). To conduct this systematic review, Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed.

3D T1-weighted turbo spin echo contrast-enhanced MRI at 1.5 T for frameless brain metastases radiotherapy.

Purpose: Performance of 3D-T1W-TSE has been proven superior to 3D-MP-GRE at 3 T on brain metastases (BM) contrast-enhanced (CE) MRI. However, its performance at 1.5 T is largely unknown and sparsely reported.

Oncologically Relevant Findings Reporting and Data System (ONCO-RADS): Guidelines for the Acquisition, Interpretation, and Reporting of Whole-Body MRI for Cancer Screening.

Acknowledging the increasing number of studies describing the use of whole-body MRI for cancer screening, and the increasing number of examinations being performed in patients with known cancers, an international multidisciplinary expert panel of radiologists and a geneticist with subject-specific expertise formulated technical acquisition standards, interpretation criteria, and limitations of whole-body MRI for cancer screening in individuals at higher risk, including those with cancer predisposition syndromes. The Oncologically Relevant Findings Reporting and Data System (ONCO-RADS) proposes a standard protocol for individuals at higher risk, including those with cancer predisposition syndromes. ONCO-RADS emphasizes structured reporting and five assessment categories for the classification of whole-body MRI findings.

Reliability of radiomics features due to image reconstruction using a standardized T -weighted pulse sequence for MR-guided radiotherapy: An anthropomorphic phantom study.

Purpose: To prospectively investigate the impact of image reconstruction on MRI radiomics features.

Methods: An anthropomorphic phantom was scanned at 1.5 T using a standardized sequence for MR-guided radiotherapy under SENSE and compressed-SENSE reconstruction settings.

The role of dopamine dysregulation and evidence for the transdiagnostic nature of elevated dopamine synthesis in psychosis: a positron emission tomography (PET) study comparing schizophrenia, delusional disorder, and other psychotic disorders.

There have been few studies performed to examine the pathophysiological differences between different types of psychosis, such as between delusional disorder (DD) and schizophrenia (SZ). Notably, despite the different clinical characteristics of DD and schizophrenia (SZ), antipsychotics are deemed equally effective pharmaceutical treatments for both conditions. In this context, dopamine dysregulation may be transdiagnostic of the pathophysiology of psychotic disorders such as DD and SZ.

Breath-hold black-blood T1rho mapping improves liver T1rho quantification in healthy volunteers.

Background Recent researches suggest that T1rho may be a non-invasive and quantitative technique for detecting and grading liver fibrosis. Purpose To compare a multi-breath-hold bright-blood fast gradient echo (GRE) imaging and a single breath-hold single-shot fast spin echo (FSE) imaging with black-blood effect for liver parenchyma T1rho measurement and to study liver physiological T1rho value in healthy volunteers. Material and Methods The institutional Ethics Committee approved this study.

Prognostic Value of Stress Dynamic Myocardial Perfusion CT in a Multicenter Population With Known or Suspected Coronary Artery Disease.

Objective: The purpose of this study was to determine the prognostic value of myocardial perfusion CT for major adverse cardiac events (MACE).

Materials And Methods: Data from six centers in Asia, Europe, and North America on 144 patients with known or suspected coronary artery disease who had undergone coronary CT angiography (CCTA) and dynamic myocardial perfusion CT with a dual-source CT system were analyzed. CCTA studies were acquired at rest.

Global quantification of left ventricular myocardial perfusion at dynamic CT imaging: Prognostic value.

Background: There is no published data on the prognostic value of global myocardial perfusion values at stress dynamic CT myocardial perfusion imaging (CTMPI).

Methods: Data of 144 patients from 6 centers who had undergone coronary CT angiography (coronary CTA) and CTMPI were assessed. Coronary CTA studies were acquired at rest; CTMPI was performed under vasodilator stress.

Statistical assessment of bi-exponential diffusion weighted imaging signal characteristics induced by intravoxel incoherent motion in malignant breast tumors.

Background: The purpose of this study is to statistically assess whether bi-exponential intravoxel incoherent motion (IVIM) model better characterizes diffusion weighted imaging (DWI) signal of malignant breast tumor than mono-exponential Gaussian diffusion model.

Methods: 3 T DWI data of 29 malignant breast tumors were retrospectively included. Linear least-square mono-exponential fitting and segmented least-square bi-exponential fitting were used for apparent diffusion coefficient () and IVIM parameter quantification, respectively.

Absolute Versus Relative Myocardial Blood Flow by Dynamic CT Myocardial Perfusion Imaging in Patients With Anatomic Coronary Artery Disease.

Objective: The purpose of this study was to evaluate differences in the diagnostic accuracy of absolute and relative territorial myocardial blood flow (MBF) derived from stress dynamic CT myocardial perfusion imaging (MPI) for the detection of significant coronary artery stenosis.

Materials And Methods: Dynamic CT MPI and coronary CT angiography (CTA) datasets from a multicenter registry of 137 patients (mean age, 60.9 ± 8.

The Enhanced Workflow and Efficiency of the Wireless Local Area Network (WLAN)-Based Direct Digital Radiography (DDR) Portable Radiography.

With the implementation of the PACS in the hospital, there is an increasing demand from the clinicians for immediate access and display of radiological images. Recently, our hospital has installed the first wireless local area network (WLAN)-based direct digital radiography (DDR) portable radiography system. The DDR portable radiography system allows wireless retrieval of modality worklist and wireless transmission of portable X-ray image on the console to the Picture Archiving and Communication System (PACS), via WLAN connection of wireless fidelity (Wi-Fi).

Magnetic resonance imaging for lung cancer screen.

Lung cancer is the leading cause of cancer related death throughout the world. Lung cancer is an example of a disease for which a large percentage of the high-risk population can be easily identified via a smoking history. This has led to the investigation of lung cancer screening with low-dose helical/multi-detector CT.

Key Performance Indicators for Comparing the Performance of Portable Radiography: Direct Digital Radiography versus Conventional Machine Computed Radiography-A Study in a Nonacute Hospital.

Introduction: Portable radiography traditionally has been performed with a conventional portable x-ray unit with computed radiography (CR) system (conventional-CR combo), and off-site processing of the exposed CR cassettes was time-consuming. The direct digital radiography (DDR) portable x-ray system, with the digital image immediately available for review and wireless transmission as the key merits, is newly installed for portable radiography. Thus, the work flow of portable radiography is changed.

Global quantification of left ventricular myocardial perfusion at dynamic CT: feasibility in a multicenter patient population.

Objective: The purpose of this study was to determine the feasibility of global quantitative measurements of left ventricular myocardial perfusion derived from stress dynamic CT myocardial perfusion imaging.

Materials And Methods: The coronary CT angiographic and CT myocardial perfusion imaging datasets of 146 patients were visually evaluated for the presence of coronary artery stenosis and perfusion defects. For the quantitative analysis, volumes of interest were defined over the entire left ventricular myocardium to obtain global myocardial blood flow (MBF), myocardial blood volume (MBV), and volume transfer constant (K(trans)).

Dynamic CT myocardial perfusion imaging: performance of 3D semi-automated evaluation software.

Objectives: To evaluate the performance of three-dimensional semi-automated evaluation software for the assessment of myocardial blood flow (MBF) and blood volume (MBV) at dynamic myocardial perfusion computed tomography (CT).

Methods: Volume-based software relying on marginal space learning and probabilistic boosting tree-based contour fitting was applied to CT myocardial perfusion imaging data of 37 subjects. In addition, all image data were analysed manually and both approaches were compared with SPECT findings.

Impact of magnetic resonance imaging on preoperative planning for breast cancer surgery.

Objectives: To review the impact of preoperative breast magnetic resonance imaging on the management of planned surgery, and the appropriateness of any resulting alterations.

Design: Retrospective review.

Setting: A private hospital in Hong Kong.

Diffusion-weighted magnetic resonance imaging of breast lesions: first experiences at 3 T.

Purpose: Dynamic contrast-enhanced magnetic resonance imaging (MRI) has been established as a valuable tool for the detection of breast cancer. There is evidence suggesting that diffusion-weighted imaging (DWI) may be useful to distinguish between malignant and benign breast lesions. We seek to evaluate the ability of DWI to differentiate between malignant and benign breast lesions at 3 T.

Magnetic resonance whole body imaging at 3 Tesla: feasibility and findings in a cohort of asymptomatic medical doctors.

Objectives: To evaluate the feasibility of whole body imaging using a 3 Tesla magnetic resonance scanner without a contrast agent, and to study the prevalence of abnormal findings among a cohort of asymptomatic doctors.

Design: Prospective study.

Setting: Private hospital, Hong Kong.

Experience of stereotactic breast biopsy using the vacuum-assisted core needle biopsy device and the advanced breast biopsy instrumentation system in Hong Kong women.

Background: Stereotactic breast biopsy of non-palpable lesions using the vacuum-assisted core needle biopsy (CNB) device and the large core excision biopsy system is a reliable biopsy method when compared with open biopsy. Its use in Western countries is well accepted. This study aimed to assess the feasibility and results of using these systems to perform stereotactic biopsy in Asian women.