Bullet characterization using Photon-Counting detector CT: A phantom study with intact bullets.

Objectives: Photon-counting detector CT (PCD-CT) is expected to substantially improve and expand CT-imaging applicability due to its intrinsic spectral capabilities, increased spatial resolution, reduced electronic noise, and improved image contrast. The current study aim is to evaluate PCD-CT efficacy in characterizing bullets based on their dimensions, shape, and material composition.

Materials And Methods: This is an observational phantom study examining 11 unfired, intact bullets of various common calibers, placed in ballistic gelatin.

A Solution for Homogeneous Liver Enhancement in Computed Tomography: Results From the COMpLEx Trial.

Objectives: The aim of the study was to reach homogeneous enhancement of the liver, irrespective of total body weight (TBW) or tube voltage. An easy-to-use rule of thumb, the 10-to-10 rule, which pairs a 10 kV reduction in tube voltage with a 10% decrease in contrast media (CM) dose, was evaluated.

Materials And Methods: A total of 256 patients scheduled for an abdominal CT in portal venous phase were randomly allocated to 1 of 4 groups.

Author Correction: Deep Learning for Fully-Automated Localization and Segmentation of Rectal Cancer on Multiparametric MR.

A correction to this article has been published and is linked from the HTML version of this paper. The error has been fixed in the paper.

Deep Learning for Fully-Automated Localization and Segmentation of Rectal Cancer on Multiparametric MR.

Multiparametric Magnetic Resonance Imaging (MRI) can provide detailed information of the physical characteristics of rectum tumours. Several investigations suggest that volumetric analyses on anatomical and functional MRI contain clinically valuable information. However, manual delineation of tumours is a time consuming procedure, as it requires a high level of expertise.

Diffusion-weighted MRI to assess response to chemoradiotherapy in rectal cancer: main interpretation pitfalls and their use for teaching.

Objectives: To establish the most common image interpretation pitfalls for non-expert readers using diffusion-weighted imaging (DWI) to assess response to chemoradiotherapy in patients with rectal cancer and to explore the use of these pitfalls in an expert teaching setting.

Methods: Two independent non-expert readers (R1 and R2) scored the restaging DW MRI scans (b1,000 DWI, in conjunction with ADC maps and T2-W MRI scans for anatomical reference) in 100 patients for the likelihood of a complete response versus residual tumour using a five-point confidence score. The readers received expert feedback and the final response outcome for each case.

First clinical experience with a dedicated MRI-guided high-intensity focused ultrasound system for breast cancer ablation.

Objectives: To assess the safety and feasibility of MRI-guided high-intensity focused ultrasound (MR-HIFU) ablation in breast cancer patients using a dedicated breast platform.

Methods: Patients with early-stage invasive breast cancer underwent partial tumour ablation prior to surgical resection. MR-HIFU ablation was performed using proton resonance frequency shift MR thermometry and an MR-HIFU system specifically designed for breast tumour ablation.

Arterial and portal venous liver perfusion using selective spin labelling MRI.

Purpose: To investigate the feasibility of selective arterial and portal venous liver perfusion imaging with spin labelling (SL) MRI, allowing separate labelling of each blood supply.

Methods: The portal venous perfusion was assessed with a pulsed EPISTAR technique and the arterial perfusion with a pseudo-continuous sequence. To explore precision and reproducibility, portal venous and arterial perfusion were separately quantified in 12 healthy volunteers pre- and postprandially (before and after meal intake).

Current clinical indications for magnetic resonance imaging of the breast.

MRI is increasingly used in breast cancer patients. MRI has a high sensitivity compared to mammography and ultrasound. The specificity is moderate leading to an increased risk of false positive findings.

The added diagnostic value of dynamic contrast-enhanced MRI at 3.0 T in nonpalpable breast lesions.

Objective: To investigate the added diagnostic value of 3.0 Tesla breast MRI over conventional breast imaging in the diagnosis of in situ and invasive breast cancer and to explore the role of routine versus expert reading.

Materials And Methods: We evaluated MRI scans of patients with nonpalpable BI-RADS 3-5 lesions who underwent dynamic contrast-enhanced 3.

Quantitative analysis of lumbar intervertebral disc abnormalities at 3.0 Tesla: value of T(2) texture features and geometric parameters.

T(2) relaxation time mapping provides information about the biochemical status of intervertebral discs. The present study aimed to determine whether texture features extracted from T(2) maps or geometric parameters are sensitive to the presence of abnormalities at the posterior aspect of lumbar intervertebral discs, i.e.

Quantitative diffusion weighted imaging for differentiation of benign and malignant breast lesions: the influence of the choice of b-values.

Purpose: To evaluate the influence of the choice of different combinations of b-values on the ADC and on the diagnostic performance of quantitative diffusion weighted imaging (DWI) in breast lesions.

Materials And Methods: Seventy-three patients (90 lesions) underwent 3 Tesla (T) breast MRI including a DWI-scan using b-values 0, 150, 499, and 1500 s/mm(2) and histological analysis. Five combinations of b-values were used to calculate the ADC, each with different sensitivities to perfusion and diffusion effects.

Do respiration and cardiac motion induce magnetic field fluctuations in the breast and are there implications for MR thermometry?

Purpose: To assess the distribution of respiration and cardiac motion-induced field fluctuations in the breast and to evaluate the implications of such fluctuations for proton resonance frequency shift (PRFS) MR thermometry in the breast.

Materials And Methods: Gradient echo MR field maps were made to study the effect of regular respiration, maximum capacity respiration, and cardiac motion on the stability of the local magnetic field in four healthy female volunteers. Field fluctuations (in parts-per-million [ppm]) were averaged over a region of interest covering both breasts.

Feasibility of MRI-guided large-core-needle biopsy of suspiscious breast lesions at 3 T.

The feasibility of large-core-needle magnetic resonance imaging (MRI)-guided breast biopsy at 3 T was assessed. Thirty-one suspicious breast lesions shown only by MRI were detected in 30 patients. Biopsy procedures were performed in a closed-bore 3-T clinical MR system on a dedicated phased-array breast coil with a commercially available add-on stereotactic biopsy device.

Breast MRI in nonpalpable breast lesions: a randomized trial with diagnostic and therapeutic outcome - MONET - study.

Background: In recent years there has been an increasing interest in MRI as a non-invasive diagnostic modality for the work-up of suspicious breast lesions. The additional value of Breast MRI lies mainly in its capacity to detect multicentric and multifocal disease, to detect invasive components in ductal carcinoma in situ lesions and to depict the tumor in a 3-dimensional image. Breast MRI therefore has the potential to improve the diagnosis and provide better preoperative staging and possibly surgical care in patients with breast cancer.

Meta-analysis of MR imaging in the diagnosis of breast lesions.

Purpose: To determine, in a meta-analysis, the diagnostic performance of contrast material-enhanced magnetic resonance (MR) imaging in patients with breast lesions.

Materials And Methods: Studies to assess the diagnostic performance of MR imaging in patients suspected of having breast cancer who underwent MR imaging and biopsy from January 1985 through March 2005 were reviewed for inclusion. A summary receiver operating characteristic curve was constructed, and pooled weighted estimates of sensitivity and specificity were calculated by using the recently developed bivariate approach for diagnostic meta-analysis.

Factors affecting the effectiveness of a projection dephaser in 2D gradient-echo imaging.

Projection dephasers are often used for background suppression and dynamic range improvement in thick-slab 2D imaging in order to promote the visibility of subslice structures, e.g., blood vessels and interventional devices.