PURPOSE: We prospectively examined the role of tumor textural heterogeneity on positron emission tomography/computed tomography (PET/CT) in predicting survival compared to other clinical and imaging parameters in non small cell lung cancer (NSCLC) patients. EXPERIMENTAL DESIGN: The feasibility study consisted of fifty-six assessed consecutive NSCLC patients (32-males; 24-females; mean-age 67±9.7y) ...

Bone histomorphometry measurements require high spatial resolution that may not be feasible using multidetector CT (MDCT). This study evaluated the trabecular microarchitecture of lumbar spine using MDCT and C-arm CT in a series of young adult patients with anorexia nervosa (AN). 11 young females with AN underwent MDCT (anisotropic resolution ...

INTRODUCTION: The study was performed to compare dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) with 3-dimensional (3D) pseudocontinuous arterial spin labeling (PCASL) MRI in gliomas with an aim to see whether arterial spin labeling (ASL)-derived cerebral blood flow (CBF) values can be used as an alternative to DCE-MRI for its ...

ABSTRACTObjective:Because a majority of urinary tract stones (UTSs) pass spontaneously and clinically significant alternative pathology is rare, we hypothesize that many computed tomographic (CT) scans to diagnose them are likely unnecessary. We sought to measure the impact of renal CT scans on resource use and to justify a prospective study ...

Anatomic Distortion of 3D Mapping. Background: Although catheter tip-tissue contact is known as a reliable basis for mapping and ablation of atrial fibrillation (AF), the effects of different mapping methods on 3-dimensional (3D) map configuration remain unknown. Methods and Results: Twenty AF patients underwent Carto-based 3D ultrasound (US) evaluation. Left atrium ...

MRI-Derived 3D-Augmented Biplane Fluoroscopy. Background: Despite the advancement of technology in electroanatomic mapping systems (EAMS), fluoroscopy remains a necessary, basic imaging modality for electrophysiology procedures. We present a feasibility study of new software that enables 3D-augmented fluoroscopy in biplane catheterization laboratories for planning and guidance of pulmonary vein isolation (PVI). The ...

BACKGROUND: Radiofrequency catheter ablation (RFCA) of atrial fibrillation is an effective and definitive treatment. The methods used to guide RFCA have evolved over the years from a purely electrophysiological approach, in which anatomical lesions were guided solely by fluoroscopy and angiographic imaging of the pulmonary veins, to an approach guided ...

Corticothalamic (CT) feedback outnumbers thalamocortical projections, and regulates sensory information processing at the level of the thalamus. It is well established that EphA7, a member of EphA receptor family, is involved in the topographic mapping of CT projections. The aim of the present study is to dissect the precise impact ...

PURPOSE: To assess the reliability of cerebral blood volume (CBV) maps as a substitute for diffusion-weighted MRI (DWI) in acute ischemic stroke. In acute stroke, DWI is often used to identify irreversibly injured "core" tissue. Some propose using perfusion imaging, specifically CBV maps, in place of DWI. We examined whether ...

Quantitative susceptibility mapping (QSM) is a novel magnetic resonance-based technique that determines tissue magnetic susceptibility from measurements of the magnetic field perturbation. Due to the ill-posed nature of this problem, regularization strategies are generally required to reduce streaking artifacts on the computed maps. The present study introduces a new algorithm ...

The C57BL mouse is the centrepiece of efforts to use gene-targeting technology to understand cerebellar pathology, thus creating a need for a detailed magnetic resonance imaging (MRI) atlas of the cerebellum of this strain. In this study we present a methodology for systematic delineation of the vermal and hemispheric lobules ...

BACKGROUND AND PURPOSE:Measurement of perfusion parameters is typically done using an intravenous injection of contrast medium. This purpose of this study was to evaluate the feasibility of measuring regional and global CBV using C-arm CT with IA injections of contrast medium.MATERIALS AND METHODS:Twelve canines were studied. CBV measurement was performed ...

To evaluate the reproducibility of presurgical functional MRI (fMRI) language mapping based on test-retest scans, comparing traditional activation t-maps to relative activation maps normalized by activation mapping as percentage of local excitation (AMPLE). Language fMRI scans were performed by 12 healthy volunteer subjects undergoing a standard clinical presurgical mapping protocol ...

PURPOSE: Accurate attenuation correction (AC) is essential for quantitative analysis of PET tracer distribution. In MR, the lack of cortical bone signal makes bone segmentation difficult and may require implementation of special sequences. The purpose of this study was to evaluate the need for accurate bone segmentation in MR-based AC ...

Accurate γ-photon attenuation correction (AC) is essential for quantitative PET/MRI as there is no simple relation between MR image intensity and attenuation coefficients. Attenuation maps (μ-maps) can be derived by segmenting MR images and assigning attenuation coefficients to the compartments. Ultrashort-echo-time (UTE) sequences have been used to separate cortical bone ...

Purpose: Dual-energy CT (DECT) is arguably the most accurate energy mapping technique in CT-based attenuation correction (CTAC) implemented on hybrid PET/CT systems. However, this approach is not attractive for clinical use owing to increased patient dose. The authors propose a novel energy mapping approach referred to as virtual DECT (VDECT) ...

OBJECTIVE: To evaluate T2* values in various histological severities of Osteoarthritis (OA). METHOD: Magnetic resonance imaging (MRI) and T2* mapping including a 3D double-echo steady-state (DESS) sequence for morphological cartilage assessment and a 3D multiecho data image combination (MEDIC) sequence for T2* mapping were conducted in 21 human femoral head ...

We present metamaterial-induced transparency (MIT) phenomena with enhanced magnetic fields in hybrid dielectric metamaterials. Using two hybrid structures of identical-dielectric-constant resonators (IDRs) and distinct-dielectric-constant resonators (DDRs), we demonstrate a larger group index (ng~354), better bandwidth-delay product (BDP~0.9) than metallic-type metamaterials. The keys to enable these properties are to excite either ...

We aim to report on the usefulness of a voxel-based morphometric MRI post-processing technique in detecting subtle epileptogenic structural lesions. The MRI post-processing technique was implemented in a morphometric analysis program (MAP), in a 30-year-old male with pharmacoresistant focal epilepsy and negative MRI. MAP gray-white matter junction file facilitated the ...

This article reports a computed inverse magnetic resonance imaging (CIMRI) model for reconstructing the magnetic susceptibility source from MRI data using a 2-step computational approach. The forward T2*-weighted MRI (T2*MRI) process is broken down into 2 steps: (1) from magnetic susceptibility source to field map establishment via magnetization in the ...

A scanning system developed for planar magnetic surfaces composed of a moving line of three magnetoresistive ultrasensitive transducers, complemented by a signal conditioning circuit is presented. After the calibration of the sensors, it was used to determine magnetized surface images with different shapes to evaluate the sensitivity of the device, ...

Unilateral hypermetabolic lesion of parotid gland demonstrated on PET/CT imaging may originate from a large spectrum of benign or malignant processes, such as adenoma, Warthin's tumor, oncocytic neoplasm, lymphoma, and primary or secondary malignancy of the gland. Bilateral and multifocal parotid gland disease is less common but possible because of ...

PURPOSE: To compare "standardization," "Gaussian normalization," and "Z-score normalization" intensity transformation techniques in dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) estimates of cerebral blood volume (CBV) in human gliomas. DSC-MRI is a well-established biomarker for CBV in brain tumors; however, DSC-MRI estimates of CBV are semiquantitative. The use of image ...

OBJECTIVE: Meniscus tear is a known risk factor for osteoarthritis (OA). Quantitative assessment of meniscus degeneration, prior to surface break-down, is important to identification of early disease potentially amenable to therapeutic interventions. This work examines the diagnostic potential of ultrashort echo time-enhanced T2∗ (UTE-T2∗) mapping to detect human meniscus degeneration ...

This study demonstrates the dependence of non-local susceptibility effects on object orientation in gradient echo MRI and the reduction of non-local effects by deconvolution using quantitative susceptibility mapping. Imaging experiments were performed on a 3T MRI system using a spoiled 3D multi-echo GRE sequence on phantoms of known susceptibilities, and ...

Attenuation correction of a single photon emission computed tomography (SPECT) image is possible using computed tomography (CT)-based attenuation maps with hybrid SPECT/CT. CT attenuation maps acquired during breath holding can be misaligned with SPECT, generating artifacts in the reconstructed images. The purpose of this study was to investigate the effects ...

[This corrects the article on p. e25451 in vol. 6.].

Objective: The goal of our prospective study was to measure the effect of a new standard model male gonad shield on the testicular radiation exposure during routine abdomino-pelvic CT. Subject and Methods: 200 male patients who underwent upper abdominal and pelvic Computerized Tomographys (CT) examinations were included in our study. ...

OBJECTIVE: To evaluate the spatio-temporal relationships between articulators in the anterior oral cavity, during the production of Japanese fricative and plosive articulation using our proposed method for tooth visualization in MR image sequences. DESIGN: Ten healthy adults without malocclusion participated in the study. Customized maxillary and mandibular plates with space ...

PURPOSE: To compare intraindividual differences in enhancement pattern of hepatic hemangiomas between gadobenate dimeglumine (Gd-BOPTA) and gadoxetate disodium (Gd-EOB-DTPA)-enhanced 3T MR imaging. MATERIALS AND METHODS: This is a HIPAA-compliant, IRB-approved retrospective study with waiver for informed consent granted. From 10/07 to 5/09, 10 patients (2 males, 8 females; mean age, ...

We report a rare injury of distal humeral epiphyseal separation in a newborn during a Caesarean section. The diagnosis was made using magnetic resonance imaging. Emergency Caesarean deliveries with considerable traction applied to extract the baby can be the risk factor of such an injury.

PURPOSE: This study was aimed to compare the accuracy, sensitivity, and positive predictive value of C-arm CT (CACT) during selective transcatheter angiography with those of multidetector CT (MDCT) in the detection of hepatocellular carcinoma (HCC). MATERIAL AND METHODS: In this prospective study, 30 patients (mean age, 73 years) with unresectable HCC ...

OBJECTIVE: We introduce a technique that uses intraoperative flat-panel detector computed tomography (FD-CT) and three-dimensional rotational angiography (3D-RA) acquired in the hybrid operative suite to provide full neuronavigation capabilities during cerebrovascular surgery without the use of preoperative imaging studies. METHODS: An Artis Zeego FD system (Siemens AG, Forchheim, Germany), mounted ...

To investigate the clinical significance of the "transitional phase" at gadoxetate disodium (Gd-EOB)-enhanced magnetic resonance imaging for diagnosing hepatocellular carcinoma (HCC). We studied 54 patients with 70 histologically diagnosed HCC. Transitional- and hepatobiliary-phase (TP, HBP) images were acquired 3 and 20 minutes after Gd-EOB injection, respectively. Radiologists measured the size ...

To characterize the changes in brown adipose tissue (BAT) occurring during puberty in boys and girls. We examined the prevalence and the volume of BAT at different stages of sexual development in 73 pediatric patients who underwent positron emission tomography (PET)/computed tomography (CT) studies. Of the 73 patients studied, 43 ...

To characterize proliferative changes in tumors during the sunitinib malate exposure/withdrawal using 3'-deoxy-3'-[(18)F]fluorothymidine (FLT) positron emission tomography (PET)/computed tomography (CT) imaging. Patients and Methods: Patients with advanced solid malignancies and no prior anti-VEGF exposure were enrolled. All patients had metastatic lesions amenable to FLT PET/CT imaging. Sunitinib was initiated at ...

Induced hypothermia is thought to work partly by mitigating reperfusion injury in asphyxiated term neonates. The purpose of this study was to assess brain perfusion in the first week of life in these neonates. In this prospective cohort study, MR imaging and ASL-PI were used to assess brain perfusion in ...

Magnetic marker monitoring (MMM) is a technique to determine the motility of the gastrointestinal tract and to observe the dissolution of pharmaceutical compounds. Todays magnetic markers usually consist of magnetized magnetite. Because of their weak magnetic fields, highly sensitive sensor systems are required. For a wider class of applications, stronger ...

: Complex distal tibial physeal fractures can be difficult to characterize on plain radiographs. The role of computed tomography (CT) scans in the evaluation and treatment decision of these injuries is unclear. We aimed to determine whether or not the addition of CT would improve the reliability of fracture classification ...

One of the new challenges of Information Technology in the medical world is the protection and authentication of a variety of digital medical files, datasets, and images. In this work, the ability of magnetic resonance imaging (MRI) slice sequences to hide digital data is investigated and more specifically the case ...

Despite the increasing use of magnetic resonance (MR) for fetal imaging, few studies have addressed the MR appearance of the normal placenta. The goal of this paper is to describe the MR features and thickness of the normal placenta during the second and early third trimester of gestation, based on ...

We sought to determine the changes in the size of the edema observed on MRI scans and its relation to the patient's pain during activity and pain during rest in bone marrow edema. A total of 26 patients were followed up at 3-month intervals for a period of 1 year. ...

Nasal expiratory positive airway pressure (nEPAP) delivered with a disposable device (Provent™ Ventus) has been shown to improve sleep disordered breathing (SDB) in some subjects. Possible mechanisms of action are (i) increased functional residual capacity (FRC) producing tracheal traction and reducing upper airway (UA) collapsibility and (ii) passive dilatation of ...

PURPOSE: To validate a monitored, breath-hold positron emission tomography (PET)/computed tomography (CT) acquisition technique for the minimization of respiratory PET/CT image misregistration and lesion distortion during PET/CT-guided percutaneous interventional procedures. MATERIALS AND METHODS: Eleven patients referred for percutaneous biopsy or thermal ablation of tumors near the diaphragm were prospectively enrolled. ...

Study Type - Diagnostic (exploratory cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Micturition cysturethrography or video urodynamics can show sequences of the micturition cycle, but are limited to show all participating structures at one. MRI is a non invasive imaging methodology to ...

To assess the feasibility of combined electromagnetic device tracking and computed tomography (CT)/ultrasonography (US)/fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) fusion for real-time feedback during percutaneous and intraoperative biopsies and hepatic radiofrequency (RF) ablation. In this HIPAA-compliant, institutional review board-approved prospective study with written informed consent, 25 patients (17 ...

Deep brain stimulation (DBS) is an established neurosurgical technique used to treat a variety of neurological disorders, including Parkinson disease, essential tremor, dystonia, epilepsy, depression, and obsessive-compulsive disorder. This study reports on the use of intraoperative MR imaging during DBS surgery to evaluate acute hemorrhage, intracranial air, brain shift, and ...

The purpose of this paper is to validate a rapid and cost-effective ex vivo technique, microCT-based virtual histology, as an alternative to MRI imaging for assessing the therapeutic response in genetically engineered mouse models of cancer. All animal procedures were conducted in accordance with the Guidelines for the Care and ...

OBJECTIVES: To clarify the changes in organic anion-transporting polypeptide 8 (OATP8) expression and enhancement ratio on gadoxetic acid-enhanced MR imaging in hepatocellular nodules during multistep hepatocarcinogenesis. METHODS: In imaging analysis, we focused on 71 surgically resected hepatocellular carcinomas (well, moderately and poorly differentiated HCCs) and 1 dysplastic nodule (DN). We ...

: The purpose of this study was to assess the feasibility of noninvasive thermometry using high-resolution computer tomography (CT) for the monitoring of bovine liver during radiofrequency (RF) ablation. : Radiofrequency probes were used to ablate bovine livers from 20°C to 98°C. During the heating process, images were acquired using ...