OBJECTIVES: The objective of this study was to investigate the stability of voxel values from cone-beam CT (CBCT) using a flat panel detector in changing surrounding circumstances mimicking clinical situations. MATERIALS AND METHODS: Seven hydroxyapatite (HA) rods (0, 40, 80, 120, 160, 199, and 239 mg Ca/cm(3) ) were set in a ...

Objective:To establish a new magnetic resonance imaging scoring system for diagnosing endolymphatic hydrops.Patients and methods:A total of 214 ears of 107 patients were categorised into five groups: no symptoms, Ménière's disease, sudden deafness, delayed endolymphatic hydrops and other ear disorders. Gadolinium distribution within the labyrinth was scored separately and quantitatively ...

Iterative reconstruction (IR) methods have recently re-emerged in transmission x-ray computed tomography (CT). They were successfully used in the early years of CT, but given up when the amount of measured data increased because of the higher computational demands of IR compared to analytical methods. The availability of large computational ...

AIM: To assess the severity of pure aortic regurgitation by measuring regurgitation volumes (RV) and fractions (RF) with dual-source computed tomography (DSCT) as compared to magnetic resonance imaging (MRI) and echocardiography. MATERIALS AND METHODS: Thirty-eight patients (15 men, 23 women; mean age 46±11 years) with isolated aortic valve regurgitation underwent ...

PURPOSE: To review the anatomical landmarks of the abdominal wall lumbar region and its normal appearance on multidetector computed tomography (MDCT) and to briefly describe the MDCT features of lumbar hernias. METHODS: We performed a retrospective search of the imaging report database from November 2007 to October 2011. We retrieved ...

INTRODUCTION AND HYPOTHESIS: The clinical evaluation of anterior vaginal wall masses can present a dilemma, as there are no well-defined pathways for diagnosis and management. Our objective was to evaluate the role and accuracy of preoperative exam and magnetic resonance imaging (MRI) for these masses. METHODS: We identified women with ...

To successfully surgically reconstruct osteochondral lesions of the talus, the exact three-dimensional (3D) configuration of the upper articular surface of the talus has to be respected. We assessed the talar geometry by measuring the coronal and sagittal talar edge radius and the frontal talar profile in multiplanar reconstructions of computer ...

There is limited understanding of the actual temperatures that maggots experience during growth. The impact of maggot mass heating on their growth rates cannot be properly factored into maggot growth rate models, thus limiting the accuracy of forensic entomology estimates. One of the major factors contributing to mass heating is ...

Background: There is a growing belief that a pretherapy scan yields little or no additional information that would impact on radioiodine ablation dosing. In addition, there is some concern regarding on the stunning effect of a pretherapy scan, especially when I-131 radioisotope is used for imaging. We hypothesized that a ...

PURPOSE: 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 ...

Background There is a heavy reliance on registrars for after-hours CT reporting with a resultant unavoidable error rate. Purpose To determine the after-hours CT reporting error rate by radiology registrars and influencing factors on this error rate. Material and Methods A 2-month prospective study was undertaken at two tertiary, level ...

Purpose: Quantification of the CT appearance of non-small cell lung cancer (NSCLC) is of interest in a number of clinical and investigational applications. The purpose of this work is to present a quantitative five-category (α, β, γ, δ, and ɛ) classification method based on CT histogram analysis of NSCLC and ...

Purpose: To develop, implement, and compare two metal artifact reduction methods for CT.Methods: Two methods for metal artifact reduction were developed. The first is based on applying corrections in a Radon transformation of the CT images. The second method is based on a forward projection of the CT images and ...

OBJECTIVE: Anterior cruciate ligament tears are frequent and if not diagnosed may lead to relevant patient disability. Magnetic resonance imaging is the method of choice for the non-invasive diagnosis of these tears. Despite the high performance of this method some cases are challenging and the criteria described in the literature ...

PURPOSE: Magnetic resonance imaging (MRI)-assisted radiation treatment planning enables enhanced target contouring. The purpose of this study is to analyze the feasibility and accuracy of computed tomography (CT) and MRI data fusion for MRI-based treatment planning in an institution where an MRI scanner is not available in the radiotherapy department. ...

PURPOSE: The aim of this study is to determine whether computer-assisted surgery (CAS) can gain more precision by utilizing information from pre-operative computed tomography (CT). METHODS: Sixty-five patients undergoing total knee arthroplasty in 2008 were included. On pre- and post-operative CT, epicondylar and posterior condylar lines were drawn and the ...

A computational pipeline combining texture analysis and pattern classification algorithms was developed for investigating associations between high-resolution MRI features and histological data. This methodology was tested in the study of dentate gyrus images of sclerotic hippocampi resected from refractory epilepsy patients. Images were acquired using a simple surface coil in ...

Object Placement of transarticular facet screws is one option for stabilization of the subaxial cervical spine. Small clinical series and biomechanical data support their role as a substitute for other posterior stabilization techniques; however, the application of transarticular facet screws in the subaxial cervical spine has not been widely adopted, ...

PURPOSE: To validate a novel approach for accelerated four-dimensional phase contrast MR imaging (4D PC-MRI) with an extended range of velocity sensitivity. MATERIALS AND METHODS: 4D PC-MRI data were acquired with a radially undersampled trajectory (PC-VIPR). A dual V(enc) (dV(enc) ) processing algorithm was implemented to investigate the potential for ...

OBJECTIVE: The main purpose of this study was to investigate the influence of exposure parameters on jawbone model accuracy when using cone beam CT (CBCT) and multi-slice CT (MSCT). METHODS: A lower and an upper edentulous human cadaver jaw were scanned using micro-CT (Skyscan NV, Kontich, Belgium) at 35 μm ...

AimsPrevious studies have used semi-automated approaches for coronary plaque quantification on multi-detector row computed tomography (CT), while an automated quantitative approach using a dedicated registration algorithm is currently lacking. Accordingly, the study aimed to demonstrate the feasibility and accuracy of automated coronary plaque quantification on cardiac CT using dedicated software ...

Features of the diffusion-time dependence of the diffusion-weighted magnetic resonance imaging (MRI) signal provide a new contrast that could be altered by numerous biological processes and pathologies in tissue at microscopic length scales. An anomalous diffusion model, based on the theory of Brownian motion in fractal and disordered media, is ...

OBJECTIVE: The aim of this study was to develop a reference system for multislice computed tomography (MSCT) images to determine of the location of impacted teeth in metric terms. STUDY DESIGN: The CT data of 17 patients with unilateral impacted maxillary canines were selected retrospectively from existing MSCT data sets. ...

ABSTRACT: Study Design. Cross-sectional study using T1rho magnetic resonance imaging (MRI) of lumbar spine in healthy young adults.Objective. To evaluate early intervertebral disc degeneration (IDD) quantified by T1ρ and T2-weighted MRI in asymptomatic young adults and to correlate T1ρ value with Pfirrmann degenerative grade, gender and body mass index (BMI).Summary ...

In computed tomography (CT), projection images of the sample are acquired over an angular range between 180 to 360 degrees around a rotation axis. A special case of CT is that of limited-angle CT, where some of the rotation angles are inaccessible, leading to artefacts in the reconstrucion because of ...

Magnetic resonance spectroscopy (MRS) is a useful tool for obtaining metabolic information non-invasively. However, low reducibility of MRS data, measuring biases caused by the operator, effects of relaxation time, and environmental contamination may sometimes become problematic. In this study, we examined contamination in echo time (TE) and the availability of ...

Safe imaging modalities are needed for evaluating parotid gland function. The aim of this study was to validate the utility of a magnetic resonance imaging (MRI) tool, equivalent cross-relaxation rate imaging (ECRI), as a measurement of parotid gland function after chemoradiotherapy. Subjects comprised 18 patients with head-neck cancer who underwent ...

An in situ procedure for calibrating equivalent magnetic area and rotation radius of rotating coils is proposed for testing accelerator magnets shorter than the measuring coil. The procedure exploits measurements of magnetic field and mechanical displacement inside a reference quadrupole magnet. In a quadrupole field, an offset between the magnet ...

An important step in the implementation of three-dimensional in vivo proton magnetic resonance spectroscopic imaging ((1) H-MRSI) of the prostate is the placement of spatial saturation pulses around the region of interest (ROI) for the removal of unwanted contaminating signals from peripheral tissue. The present study demonstrates the use of ...

PURPOSE: Accurate delineation of the prostate gland on computed tomography (CT) remains a persistent challenge and continues to introduce geometric uncertainty into the planning and delivery of external beam radiotherapy. We, therefore, developed an expansion/de-expansion tool to quantify the contour errors and determine the location of the deviations. METHODS AND ...

High-resolution phase-contrast X-ray computed tomography (CT) reveals the phoretic deutonymph of a fossil astigmatid mite (Acariformes: Astigmata) attached to a spider's carapace (Araneae: Dysderidae) in Eocene (44-49 Myr ago) Baltic amber. Details of appendages and a sucker plate were resolved, and the resulting three-dimensional model demonstrates the potential of tomography ...

Calculations of nuclear magnetic shielding polarizabilities of the P-hexahelicene and 8,9-difluoro-P-hexahelicene molecules have been accomplished at the CTOCD-DZ2/6-31G(d,p) level. Pseudoscalars of the nuclear magnetic shielding polarizability are the largest reported so far for second-row atoms. The rf voltage generated by the rotating chiral electric polarization, induced by the permanent magnetic ...

We compared the prostate volumes and rectal doses calculated by CT and CT-MRI fusion, and verified the usefulness of CT-MRI fusion in three-dimensional (3D) radiotherapy planning for localized prostate cancer. Three observers contoured the prostate and rectum of 13 patients with CT and CT-MRI fusion. Prostate delineations were classified into ...

Current concerns focus on the high doses encountered in computed tomography (CT) examinations as they are extending towards younger and more radiosensitive patients. Previous work produced conversion coefficients for effective dose (E) from dose-length product (DLP) for four anatomical body regions applicable to any patient size. This work aims to ...

We have developed a practice procedure for prostate lymphoscintigraphy using SPECT/CT and filtered (99m)Tc-sulfur nanocolloid, as an alternative to the proprietary product (99m)Tc-Nanocoll, which is not approved in the United States. Ten patients were enrolled for this study, and all received radiotracer prepared using a 100-nm membrane filter at a ...

Endocasts provide evidence on size and shape characteristics, blood supply trajectories, and neurological features of the brain, allowing comparative analyses of fossil hominins crucial to our understanding of human brain evolution. Here, we assess the morphological features of the virtual endocast of the Cioclovina Upper Paleolithic calvarium, one of the ...

Object The current standard of practice for clearance of the cervical spine in obtunded patients suffering blunt trauma is to use CT and an adjuvant imaging modality (such as MR imaging). The objective of this study was to determine the comparative effectiveness of multislice helical CT alone to diagnose acute ...

RATIONALE AND OBJECTIVES: At lower magnetic field strengths, regional differences of cerebral metabolite distributions have been described, but these data are controversial. Magnetic resonance spectroscopy at 7 T is expected to deliver high spectral resolution and good differentiation, but there are problems arising at high magnetic field strengths that may ...

A (1) H magnetic resonance spectroscopic imaging study at 3T and short echo time was conducted to evaluate both the reproducibility, as measured by the interscan coefficient of variation (CV), and test-retest reliability, as measured by the intraclass correlation coefficient (ICC), of measurements of glutamate (Glu), combined glutamate and glutamine ...

Converging evidence from neuroimaging and neuropsychological studies indicates that heavy marijuana use is associated with cingulate dysfunction. However, there has been limited human data documenting in vivo biochemical brain changes after chronic marijuana exposure. Previous proton magnetic resonance spectroscopy studies have demonstrated reduced basal ganglia glutamate and dorsolateral prefrontal cortex ...

BACKGROUND AND PURPOSE: Despite the improving imaging techniques, it remains challenging to predict the outcome early after transient cerebral ischemia. The aim of this study was thus to identify early metabolic biomarkers for outcome prediction. METHODS: We modeled transient ischemic attacks and strokes in mice. Using high-field MR spectroscopy, we ...

Over the last decade, several papers have focused on the construction of highly detailed mouse high field magnetic resonance image (MRI) templates via non-linear registration to unbiased reference spaces, allowing for a variety of neuroimaging applications such as robust morphometric analyses. However, work in rats has only provided medium field ...

The intrinsic nonuniformities in the transmit radiofrequency field from standard quadrature volume resonators at high field are particularly problematic for localized MRS in areas such as the temporal lobe, where a low signal-to-noise ratio and poor metabolite quantification result from destructive B(1) (+) field interference, in addition to line broadening ...

Attentional dysfunction is one of the most consistent findings in individuals with autism spectrum disorders (ASD). However, the significance of such findings for the pathophysiology of autism is unclear. In this study, we investigated cellular neurochemistry with proton magnetic resonance spectroscopy imaging ((1)H-MRS) in brain regions associated with networks subserving ...

Introduction: This study conducted spectroscopic analyses using proton (1H) Magnetic Resonance Spectroscopy (at 4 Tesla) in a sample of adolescents with Attention Deficit Hyperactivity Disorder (ADHD), before and after treatment with extended release methylphenidate (OROS MPH), as compared to a sample of healthy comparators. Aims: The main aim of this ...

Although carpal tunnel syndrome (CTS) is the most common entrapment neuropathy in adults, its etiology is not completely known. Chronic inflammation, fibrosis of the transverse carpal ligament (TCL), and altered sensory response contribute to the symptoms. Because substance P (SP) is known to be involved in neuropathic pain, chronic inflammation, ...

Acupuncture is a widely used symptomatic treatment for carpal tunnel syndrome (CTS). The objective of this systematic review was to evaluate the evidence of the effectiveness of acupuncture and acupuncture-like treatments for CTS. Systematic searches were conducted on 11 electronic databases without language restrictions. All randomized controlled trials (RCTs) of ...

Objectives. To study with MRI the hands of consecutive PMR patients, who were not selected on the basis of peripheral arthritis, with a correlation to clinical and laboratory findings. Methods. Twenty-six hands of 15 PMR patients and 26 hands of 13 healthy controls were studied by extremity-dedicated MRI for the ...

To compare tomosynthesis with radiography for the detection of hand and wrist bone erosions in patients with rheumatoid arthritis (RA), using multidetector computed tomography (CT) as the reference method. The study was approved by the local ethics committee, and written consent was obtained from all patients. From December 2008 to ...

Diagnostic tests in patients complaining of carpal tunnel syndrome (CTS) are based on physical examination, electrodiagnostic tests (EDTs), and diagnostic imaging. Timely diagnosis helps prevent permanent nerve damage and its sequelae in terms of functional impairment. Imaging provides additional information to that obtained from clinical tests and EDTs. By allowing ...