Headaches are described as primary, where no contributing cause is found, or secondary, where a discrete lesion or other condition has triggered the phenotype. Primary headache is a common condition; migraine causes much of the morbidity in this population, at great personal and economic cost. The decision to use MRI ...

We sought to describe quantitatively the distribution of rectally administered gels and seminal fluid surrogates using novel concentration-distance parameters that could be repeated over time. These methods are needed to develop rationally rectal microbicides to target and prevent HIV infection. Eight subjects were dosed rectally with radiolabelled and gadolinium-labelled gels ...

We present a simple method for direct and solvent-free formation of amides from carboxylic acids and amines using radiofrequency heating. The direct energy coupling of the AC magnetic field via nickel ferrite magnetic nanoparticles enables fast and controllable heating, as well as enabling facile work-up via magnetic separation.

Tablet computers such as the iPad, which have a large format, improved graphic display resolution and a touch screen interface, may have an advantage compared to existing mobile devices such as smartphones and laptops for viewing radiological images. We assessed their potential for emergency radiology teleconsultation by reviewing multi-image CT ...

To obtain diagnostic performance values of CT, MRI, ultrasound and 18-fludeoxyglucose positron emission tomography (PET)/CT for staging of hilar cholangiocarcinoma. A comprehensive systematic search was performed for articles published up to March 2011 that fulfilled the inclusion criteria. Study quality was assessed with the quality assessment of diagnostic accuracy studies ...

This study aimed to discriminate between enamel and composite resins by differences in Hounsfield units shown on 16 section multidetector CT (MDCT) images taken of unidentified bodies. First, we determined the Hounsfield units of composite resins in 15 extracted human teeth. We then filled a single cavity prepared in each ...

An automatic, accurate and fast segmentation of hemorrhage in brain Computed Tomography (CT) images is necessary for quantification and treatment planning when assessing a large number of data sets. Though manual segmentation is accurate, it is time consuming and tedious. Semi-automatic methods need user interactions and might introduce variability in ...

The goal of this article is to summarize the literature about the diagnosis of meniscal tears on MRI including the normal appearance of the meniscus and the appearance of the various types of meniscal tears. In addition, I discuss my experience with the causes of errors in the MR diagnosis ...

OBJECTIVES: To predict the primary neuroendocrine tumour of the gastrointestinal tract site based on observed metastatic sites. METHODS: We studied data from the radiology database of a single, large cancer centre on 250 patients with pathologically confirmed neuroendocrine tumours. Primary tumour sites and the locations of metastases were collected from ...

Several practical obstacles in data handling and evaluation complicate the use of quantitative localized magnetic resonance spectroscopy (qMRS) in clinical routine MR examinations. To overcome these obstacles, a clinically feasible MR pulse sequence protocol based on standard available MR pulse sequences for qMRS has been implemented along with newly added ...

PURPOSE: To determine the accuracy of routine magnetic resonance imaging (MRI) in the grading of knee cartilage lesions through a meta-analysis. METHODS: A search of English-language literature published before February 2012 was carried out in PubMed. Articles using arthroscopy as a gold standard, a 6-knee region dividing method, and a ...

Low-field MRI (lfMRI) has become increasingly accepted as a method for diagnosing canine meniscal tears in clinical practice. However, observer effects on diagnostic accuracy have not been previously reported. In this study, 50 consecutive stifle joints with clinical and radiologic evidence of cranial cruciate ligament insufficiency were investigated by lfMRI ...

Protection at positron emission tomography-computed tomography (PET-CT) installations is the most complex problem in the field of designing structural protection from ionising radiation in medical practice. This paper provides a discussion on the values for shield widths obtained from two different estimation methods, as well as of certain theoretical differences ...

PURPOSE: Magnetic resonance imaging (MRI) is the most current diagnostic imaging procedure for suspected ACL injuries. It is an accurate, highly sensitive and specific tool for the diagnosis of ACL tears, graft tears and associated injuries. However, it can also be used for various other aspects of anatomic ACL reconstruction. ...

PURPOSE: Clinical PET/MR acquisition protocols entail the use of MR contrast agents (MRCA) that could potentially affect PET quantification following MR-based attenuation correction (AC). We assessed the effect of oral and intravenous (IV) MRCA on PET quantification in PET/MR imaging. METHODS: We employed two MRCA: Lumirem® (oral) and Gadovist® (IV). ...

Enlargement and dysfunction of the right ventricle (RV) is a sign and outcome predictor of many cardiopulmonary diseases. Due to the complex geometry of the RV exact volumetry is cumbersome and time-consuming. We evaluated the performance of prototype software for fully automated RV segmentation and volumetry from cardiac CT data. ...

BACKGROUND: The mechanical alignment of the knee is an important factor in planning for, and subsequently assessing the success of a knee replacement. It is most commonly measured using a long-leg anteroposterior radiograph (LLR) encompassing the hip, knee and ankle. Other modalities of measuring alignment include computer tomography (CT) and ...

Distinguishing pulmonary arterial and venous (A/V) trees via in vivo imaging is a critical first step in the quantification of vascular geometry for the purpose of diagnosing several pulmonary diseases and to develop new image-based phenotypes. A multi-scale topo-morphologic opening (MSTMO) algorithm has recently been developed in our laboratory for ...

PURPOSE: To determine the intraobserver and interobserver agreement on the geometric classification and 2-dimensional measurements of rotator cuff tears based on magnetic resonance arthrography. METHODS: We retrospectively reviewed preoperative magnetic resonance arthrograms of 73 consecutive patients who were surgically treated for their full-thickness rotator cuff tears. The images were blinded ...

Quantitative PET imaging requires an attenuation map to correct for attenuation. In stand-alone PET or PET/CT, the attenuation map is usually derived from a transmission scan or CT image, respectively. In PET/MR, these methods will most likely not be used. Therefore, attenuation correction has long been regarded as one of ...

PURPOSE: Due to the time factor in polytraumatized patients all relevant pathologies in a polytrauma computed tomography (CT) scan have to be read and communicated very quickly. During radiology residency acquisition of effective reading schemes based on typical polytrauma pathologies is very important. Thus, an online tutorial for the structured ...

BACKGROUND: To obtain diagnostic performance values of T2-weighted imaging (T2WI) and contrast-enhanced magnetic resonance imaging (CE-MRI) in the prediction of myometrial invasion in patients with endometrial cancer. METHODS: Databases including MEDLINE and EMBASE were searched for relevant original articles published from January1995 to March 2012. Pooled estimation data were obtained ...

OBJECTIVES: The aim of this study was to determine the accuracy and reliability of shoulder magnetic resonance (MR) arthrography with three-dimensional (3D) isotropic intermediate-weighted turbo spin-echo (TSE) sampling perfection with application-optimised contrasts using different flip angle evolution (SPACE) in the diagnosis of superior labrum anterior-to-posterior (SLAP) lesions compared with two-dimensional ...

OBJECTIVE: To develop a dual-energy CT (DECT) method for differentiating uric acid (UA) from non-UA stones in the presence of iodinated contrast medium. METHODS: Thirty UA and 45 non-UA stones were selected after infra-red spectroscopic analysis and independently placed in a 1.5-ml vial, which was filled first with saline and ...

Aim To determine the variability in CT measurements of proximal thoracic aortic diameters obtained using double-oblique short axis and semiautomatic centerline analysis techniques. Institutional review board approval, with waiver of informed consent, was obtained for this HIPAA-compliant, retrospective study. Cardiac gated thoracic aortic CT scans were evaluated in 25 patients. ...

Surgical targeting of the incorrect vertebral level (wrong-level surgery) is among the more common wrong-site surgical errors, attributed primarily to the lack of uniquely identifiable radiographic landmarks in the mid-thoracic spine. The conventional localization method involves manual counting of vertebral bodies under fluoroscopy, is prone to human error and carries ...

ABSTRACT: Study Design. Biomechanic and radiographic studyObjective. Accurate assessment of vertebrae stiffness and strength at discrete sites in-vivo is important for surgical treatment.Summary of Background Data. We have not found published methods which allow in-vivo evaluation of bone mechanical properties at discrete sites of vertebral body applicable for clinical use.We ...

The concurrent application of TMS and MRI is challenging due to the MR-image artifacts, which are produced by using the two techniques in combination. One such artifact arises from the introduction of radio frequency noise through the lead of the TMS-coil into the scanner. Here we describe four methods used ...

To compare the keratometric values measured by the automated keratometer, two Placido-based computerized topography systems (Dicon CT 200 [Vismed Inc] and Allegro Topolyzer [WaveLight Inc]), and Scheimpflug analysis (Pentacam [Oculus Optikgeräte GmbH]). The keratometric data of 200 eyes from 200 patients evaluated for refractive surgery were reviewed retrospectively. Mean simulated ...

The aim of this study was to quantify the effect of four image registration methods on lung texture features extracted from serial computed tomography (CT) scans obtained from healthy human subjects. Two chest CT scans acquired at different time points were collected retrospectively for each of 27 patients. Following automated ...

To develop a method for creating variable planning margins around a clinical treatment volume (CTV) and to evaluate its application in head and neck cancer radiotherapy in accounting for locoregional variations of nonrigid setup uncertainties. Ten computed tomography (CT) images (with a resolution of 0.68 × 0.68 × 2.5 mm(3)) ...

To compare the breast volume (BV), fibroglandular tissue volume (FV), and percent density (PD) measured from breast MRI of the same women using four different MR scanners. The study was performed in 34 healthy Asian volunteers using two 1.5T (GE and Siemens) and two 3T (GE and Philips) MR scanners. ...

Regional lung volume change as a function of lung inflation serves as an index of parenchymal and airway status as well as an index of regional ventilation and can be used to detect pathologic changes over time. In this paper, the authors propose a new regional measure of lung mechanics-the ...

Purpose: To evaluate the maximum performance gain that can theoretically be achieved with differential phase contrast computed tomography (PCT) compared with absorption-based CT, applied to in vivo medical imaging.Methods: We develop a mathematical framework for analyzing the performance of PCT relative to CT under ideal conditions. We validate our model ...

BackgroundThanks to the development of computed tomography (CT) scanners and computer software, accurate coronary artery segmentation can be achieved with minimum user interaction. However, the question remains whether we can use these segmented images for reliable diagnosis.PurposeTo retrospectively evaluate the diagnostic accuracy of coronary CT angiography (CCTA) using segmented 3D ...

: To estimate the proportion of tubal factor infertility (TFI) caused by Chlamydia trachomatis (CT), the etiologic fraction, from a retrospective study of CT antibody prevalence in TFI cases and controls, adjusted for sensitivity and specificity. : We use published data on sensitivity and specificity to estimate the performance of ...

The purposes of this retrospective study were to compare various methods of apparent diffusion coefficient (ADC) measurement for head and neck lesions in half-Fourier single-shot turbo spin-echo (HASTE) diffusion-weighted imaging (DWI) and determine the threshold ADC value for predicting malignancy. HASTE DW images of 46 lesions (10 cysts, 14 benign ...

A CT-SD16 semiconductor detector was calibrated in terms of the computed tomography (CT) air kerma index for the integration length L = 100 mm, C(K,PMMA,100), in the cylindrical CT head and body dosimetry phantoms using a DCT10 pencil ionization chamber as a reference instrument. Using IEC RQT 9 120-kV x-ray radiation ...

PURPOSE:: To assess the use of serial computed tomography (CT) in the detection of osteo-odonto-lamina resorption in osteo-odonto-keratoprosthesis (OOKP) and to investigate the use of new volumetric software, Advanced Lung Analysis software (3D-ALA; GE Healthcare), for detecting changes in OOKP laminar volume. METHODS:: A retrospective assessment of the radiological databases ...

Accurate localization of interventional devices, for example, needles and brachytherapy seeds, is desired for interventional procedures. MRI is usually considered unsuitable for this purpose, as the induced signal voids and signal pile-ups do not necessarily represent the exact location of the devices. Center-out radial sampling with off-resonance reception (co-RASOR) has ...

MR-based methods provide low risk, noninvasive assessment of joint kinematics; however, these methods often use static positions or require many identical cycles of movement. The study objective was to compare the 3D kinematic results approximated from a series of sequential static poses of the knee with the 3D kinematic results ...

OBJECTIVES: Micro-CT provides three-dimensional details and has been widely used for biomedical assessments. This study aims to determine the most appropriate threshold method for quantitatively assessing the dynamics of periodontal destruction. METHODS: Inflammation was induced by submerging a silk ligature in the sulcus of the maxillary second molars of rats, ...

Objectives: To compare the difference and agreement of the morphology of distal border synovial invaginations on a dorsoproximal-palmarodistal oblique (DPr-PaDiO) projection with hoof-specific angle versus computed tomography. Methods: Computed tomography (CT) scans and a DPr-PaDiO radiographic projection with hoof-specific angle were obtained on 50 cadaveric forefeet from 25 Warmblood horses. ...

Recently, a novel classification system based on tumour architecture and with high prognostic impact has been proposed for pulmonary adenocarcinomas (ADC). For imaging-based prediction of histologic ADC subtypes and thus prognosis, it is of paramount importance to investigate the correlations of radio- and histomorphological parameters.Associations between histomorphologic ADC growth patterns ...

OBJECTIVES: Dose reduction has become a major issue in computed tomography (CT). The benefit of kilovolt (kV) reduction has been demonstrated in CT angiography. We sought to evaluate an attenuation-based fully automated kV-selection and milliampere second-adaption algorithm for CT and to assess radiation dose and image quality in comparison with ...

A novel method for estimating a field of fiber orientation distribution (FOD) based on signal de-convolution from a given set of diffusion weighted magnetic resonance (DW-MR) images is presented. We model the FOD by higher order Cartesian tensor basis using a parametrization that explicitly enforces the positive semi-definite property to ...

OBJECTIVE: To create 3DMR osseous models of the shoulder similar to 3DCT models using a gradient-echo-based two-point/Dixon sequence. MATERIALS AND METHODS: CT and 3TMR examinations of 7 cadaveric shoulders were obtained. Glenoid defects were created in 4 of the cadaveric shoulders. Each MR study included an axial Dixon 3D-dual-echo-time T1W-FLASH ...

Purpose:To evaluate the feasibility of using virtual noncontrast material-enhanced (VNC) computed tomographic (CT) series derived from dual-energy CT imaging studies for coronary artery calcium quantification.Materials and Methods:This HIPAA-compliant study was institutional review board approved; all patients provided written informed consent. Thirty-six patients prospectively underwent noncontrast-enhanced CT calcium scoring followed by ...

AIM: To evaluate image quality and diagnostic accuracy of two- (2D) and three-dimensional (3D) T2-weighted magnetic resonance imaging (MRI) for the evaluation of deep infiltrating endometriosis (DIE). MATERIALS AND METHODS: One hundred and ten consecutive patients with suspicion of endometriosis were recruited at two institutions over a 5-month period. Twenty-three ...

PURPOSE: This work aims to develop a methodology for automated atlas-guided analysis of small animal positron emission tomography (PET) data through deformable registration to an anatomical mouse model. METHODS: A non-rigid registration technique is used to put into correspondence relevant anatomical regions of rodent CT images from combined PET/CT studies ...