Recent theoretical advances in the field of compressive sampling-also referred to as compressed sensing (CS)-hold considerable promise for practical applications in MRI, but the fundamental condition of sparsity required in the CS framework is usually not fulfilled in MR images. However, in dynamic imaging, data sparsity can readily be introduced ...

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is today the most popular method to assess perfusion in the body. Unfortunately, the technique is mostly used to determine semiquantitative parameters like time to peak enhancement. Perfusion quantification remains challenging using DCE-MRI. The method suffers from two major limitations. First, no standardized imaging ...

PURPOSE: To prospectively use dynamic contrast material-enhanced magnetic resonance (MR) imaging and a tracer kinetic model to compare parotid gland microvascular characteristics in patients who have Sjögren syndrome (SS) with those in healthy volunteers. MATERIALS AND METHODS: The local research ethics committee approved the study, and written informed consent was ...

Catalysis is vital to industrial chemistry, and the optimization of catalytic reactors attracts considerable resources. It has proven challenging to correlate the active regions in heterogeneous catalyst beds with morphology and to monitor multistep reactions within the bed. We demonstrate techniques, using magnetic resonance imaging and para-hydrogen (p-H2) polarization, that ...

Dynamic Contrast Enhanced MRI (DCE-MRI) is today one of the most popular methods for tumor assessment. Several pharmacokinetic models have been proposed to analyze DCE-MRI. Most of them depend on an accurate arterial input function (AIF). We propose an automatic and versatile method to determine the AIF. The method has ...

Evaluation of solitary pulmonary nodules (SPNs) poses a challenge to radiologists. Chest computed tomography (CT) is considered the standard technique for assessing morphologic findings and intrathoracic spread of an SPN. Although the clinical role of magnetic resonance imaging (MRI) for SPNs remains limited, considerable experience has been gained with MRI ...

AIMS: To assess and compare the reliability of dynamic MRI to quantify pelvic organ prolapse (POP) according to the International Continence Society (ICS) using two different reference lines, and to determine which line gives the best concordance with clinical examination. METHODS: Forty-seven patients with genital prolapse underwent physical examination and ...

The formation of a primary vascular bed is a dynamic process, aspects of which are readily amenable to time-lapse imaging in avian embryos. At early developmental stages, the body plan of avian embryos is very similar to mammals and has many properties that make it ideal for imaging. We devised ...

BACKGROUND: Highly malignant gliomas are characterized by rapid growth, extensive local tissue infiltration and the resulting overall dismal clinical outcome. Gaining any additional insights into the complex interaction between this aggressive brain tumor and its microenvironment is therefore critical. Currently, the standard imaging modalities to investigate the crucial interface between ...

We report two patients presenting with marked clinical unilateral enophthalmos who had positional variability and dynamic proptosis on valsalva. On orbital imaging, enophthalmos was not documented and in fact, globe proptosis of the same side was reported for one of the patients. During CT and MRI scanning patients are often ...

PURPOSE: To identify regional arterial input functions (AIFs) using factor analysis of dynamic studies (FADS) when quantification of perfusion is performed using model-free arterial spin labelling. MATERIAL AND METHODS: Five healthy volunteers and one patient were examined on a 3-T Philips unit using quantitative STAR labelling of arterial regions (QUASAR). ...

OBJECTIVE: In the last 10 years, experience with endoscopic transsphenoidal surgery for the treatment of sellar and perisellar lesions has highlighted advantages brought about by the endoscope for less-invasive procedures. Focusing on these advantages, there is increasing interest in endoscope use for treatment of lesions located in other regions such ...

For the purpose of continual measurement of the T1 value using the FSE (fast spin-echo) sequence and evaluation of the hemodynamics, we assessed T1 values when the imaging parameters were changed. Moreover, with the imaging parameters derived from this study, dynamic contrast-enhanced MR imaging (MRI) was examined in prostatic disease. ...

Accurate registration of the corresponding non-enhanced and arterial-phase CT images is necessary to create temporal and dynamic subtraction images for the enhancement of subtle abnormalities. However, respiratory movement causes misregistration at the periphery of the liver. To reduce these misregistration errors, we developed a temporal and dynamic subtraction technique to ...

RATIONALE AND OBJECTIVES: In this article, we propose an alternative approach to voxel-by-voxel analysis, which overcomes problems associated with heuristic methods currently used for dynamic contrast-enhanced MRI (DCE-MRI) data assessment. We aim to allow fully automated extraction of various heuristic parameters via robust preprocessing methods and a new technique for ...

In the k-t sensitivity encoding (k-t SENSE) method spatiotemporal data correlations are exploited to accelerate data acquisition in dynamic MRI studies. The present study demonstrates the feasibility of applying k-t SENSE to contrast-enhanced myocardial perfusion MRI and using the speed-up to increase spatial resolution. At a net acceleration factor of ...

The purpose of this study was to evaluate optimal breathing maneuvers that minimize lung parenchymal movement for dynamic contrast-enhanced MRI (DCE-MRI), which requires longer scan times, beyond the limit of a single breath hold. A healthy volunteer was scanned on a 3T MR scanner using two different breathing maneuvers. In ...

Semarang coastal area has geomorphologically complex processes, such as erosion-sedimentation, land subsidence, and tidal inundation hazard. Multi-years shoreline mapping is considered a valuable task for coastal monitoring and assessment. This paper presents maps illustrating the shoreline dynamic in a coastal area of Semarang-Indonesia using multi-sources spatial data. The segment data ...

Dynamic contrast-enhanced MRI (DCE-MRI) of the hand and wrist was performed in 11 patients with rheumatoid arthritis twice before and once 2 weeks after treatment with anti-tumor necrosis factor (TNF)-alpha therapy. A rapid, T1-weighted 3D spoiled gradient echo (SPGR) sequence was used for the dynamic imaging. T1 estimation was performed ...

Dynamic contrast-enhanced (DCE-) MRI is often used to evaluate the response to experimental antiangiogenic therapies in small animal models of cancer. Unfortunately, DCE-MRI studies often require a substantial investment of both time and money to achieve the desired level of statistical significance. Multiple-mouse MRI has previously been used to improve ...

Although neoadjuvant chemoradiation eradicates esophageal adenocarcinoma in a substantial proportion of patients, conventional imaging techniques cannot accurately detect this response. Dynamic contrast-enhanced magnetic resonance imaging is an emerging approach that may be well suited to fill this role. This pilot study evaluates the ability of this method to discriminate adenocarcinoma ...

A simple, modified method to evaluate changes in the nasolabial soft tissues after orthognathic surgery is presented. Eighteen healthy volunteers were photographed in a standardized manner with a 2-month interval. Pictures were taken with the soft tissues in repose and 'maximum closed mouth smile'. Discrepancies for repose and dynamic excursions ...

We developed a dynamic magnetic resonance (MR) angiographic imaging protocol that can aide the diagnosis of subclavian steal syndrome (SSS). Our protocol combines a new pulse sequence: time-resolved echo-shared angiographic technique (TREAT) with parallel imaging: generalized autocalibrating partially parallel acquisition (GRAPPA). Our pulse sequence, like traditional catheter angiography exams, provides ...

Dynamic CT scanning after intravenous injection of iodine contrast medium (CM) was proposed in the very early days of CT. The goal was to characterize tissue by extracting information from the temporal course of enhancement. In the early 1980s, modeling algorithms were already described in the literature for the quantitative ...

OBJECTIVE: To evaluate the value of adding fat-suppressed (FS) T1-weighted magnetic resonance imaging (MRI) with orally administered superparamagnetic iron oxide (SPIO) to the 3-dimensional dynamic MRI for revealing ampullary carcinomas. MATERIALS: Twenty-five patients with ampullary carcinoma who underwent MRI with orally administered SPIO, including a FS T1-weighted fast low-angle shot ...

PURPOSE: To assess the feasibility of dynamic MRI of swallowing in a seated position using an open-configuration MRI scanner, and to compare its capacity for motion analysis around the pharyngeal wall with that of videofluorography. MATERIALS AND METHODS: Six healthy individuals (four women and two men, mean age = 31.4 ...

BACKGROUND: Zoonotic cutaneous leishmaniasis (ZCL) is endemic in many rural areas of the Southern and Eastern Mediterranean region where different transmission patterns of the disease have been described. This study was carried out in a region located in Central Tunisia and aimed to investigate the spatio-temporal dynamics of the disease ...

RATIONALE AND OBJECTIVES: To evaluate the ability of dynamic contrast-enhanced magnetic resonance imaging (MRI) to differentiate several tumor entities of the parotid gland in a prospective clinical trial. MATERIALS AND METHODS: A total of 112 patients with parotid tumors were examined with dynamic contrast-enhanced 1.5 T MRI. Precontrast axial T1-weighted ...

Prolapse of pelvic organs in a female can be simple or complex. To make a definite diagnosis of pelvic prolapse preoperatively, dynamic magnetic resonance (MR) is an alternative to conventional fluoroscopic or sonographic examination, with the advantage of providing greater details, and thus helping the surgeon to have a good ...

Connections from hippocampus to septal nuclei have been implicated in memory loss and the cognitive impairment in Down syndrome (DS). We trace these connections in living mice by Mn(2+) enhanced 3D MRI and compare normal with a trisomic mouse model of DS, Ts65Dn. After injection of 4 nl of 200 ...

Anuran amphibians undergo a rapid and dramatic process of metamorphosis featuring widespread structural reorganization of the central nervous system. Although morphological changes during embryonic stages of anuran development have been well documented, much less information is available describing structural changes in the brain during larval (tadpole) stages. Using still images ...

Angiogenesis, long recognized as a key factor in tumor growth and metastasis, has been the target of new anticancer treatment paradigms. Development of antiangiogenesis drugs is challenging, mainly due to the difficulty of determining the correct dosage and the time required to observe a clinical effect. In the past decade, ...

OBJECTIVE: To determine the added value of gadolinium-enhanced dynamic magnetic resonance (MR) images compared with unenhanced and MR cholangiography (MRC) images, to evaluate the longitudinal extension of bile duct cancer. MATERIALS AND METHOD: Thirty-three patients with hilar cholangiocarcinoma or common duct cancer who had undergone MRC, unenhanced, and gadolinium-enhanced dynamic ...

PURPOSE: To evaluate the use of a dynamic keyhole magnetic resonance angiography (MRA) sequence combined with sensitivity encoding (SENSE) for hemodialysis shunts, because surveillance with conventional contrast-enhanced MRA (CE-MRA) is limited by its low temporal resolution, resulting in arteriovenous overlay. MATERIALS AND METHODS: A total of 12 patients with Brescia-Cimino ...

PURPOSE: To evaluate the feasibility of noninvasive dynamic fast magnetic resonance imaging (MRI) during swallowing in healthy volunteers, and to determine esophageal function at the gastroesophageal junction during swallowing. MATERIALS AND METHODS: A total of 20 healthy volunteers underwent MRI while swallowing in the supine position. Dynamic gradient-echo (GRE) sequences ...

OBJECTIVE: To assess the accuracy of dynamic expiratory CT for detecting airway malacia using bronchoscopy as the diagnostic "gold standard." MATERIALS AND METHODS: A computerized hospital information system was used to retrospectively identify all patients with bronchoscopically proven airway malacia referred for CT airway imaging at our institution during a ...

This work studies the influence of dynamic biomimetic coating procedures on the growth of bone-like apatite layers at the surface of starch/polycaprolactone (SPCL) scaffolds produced by a 3D-plotting technology. These systems are newly proposed for bone Tissue Engineering applications. After generating stable apatite layers through a sodium silicate-based biomimetic methodology ...

BACKGROUND AND PURPOSE: 3D-CT angiography (3D-CTA), a vessel-cast technique, is useful in the diagnosis of patients with brain lesions and cerebrovascular disease. However, it provides no information on blood-flow dynamics. Therefore, we developed a new technique, dynamic 3D-CTA (d3D-CTA), that yields 3D images of the vasculature and allows assessment of ...

18F-FRP170, 1-(2-fluoro-1-[hydroxymethyl]ethoxy)methyl-2-nitroimidazole, is a new hypoxia imaging agent for positron emission tomography. This compound was synthesized by 18F-labeling of RP170, which was developed as a new hydrophilic 2-nitroimidazole analog. In the present study, we analyzed dynamic whole-body imaging in healthy volunteers and dynamic tumor imaging in three patients with lung ...

Daghini et al used a pig model to estimate single-kidney GFR with dynamic contrast-enhanced CT scanning. Three techniques were evaluated, two of which (the modified Patlak method and the gamma variate model) yielded GFR estimates that correlated significantly with determinations made by using standard inulin clearance techniques. The findings hold ...

PURPOSE: Chronic coccygodynia is a difficult problem diagnostically and therapeutically. Moreover, there is no deep knowledge especially in the field of imaging of chronic coccygodynia. In this study several possible measurements are proposed, which all are able to demonstrate coccygeal movement during defecation, in order to assess coccygeal mobility using ...

Contrast-Enhancement (CE) is an innovative approach, used in radiological framework, to evaluate the vascularization of the diseases. This non-invasive method determines the nature of a diseases, analysing the perfusion' dynamic of contrast media in the tissues. In this paper we present an innovative tool named DyCoH (Dynamic Contrast Enhancement). This ...

Our aims were to assess diagnostic performance of T2-weighted (T2W) and dynamic gadolinium-enhanced T1-weighted (T1W) magnetic resonance imaging (MRI) in the preoperative assessment of myometrial and cervical invasion by endometrial carcinoma and to identify imaging features that predict nodal metastases. Two radiologists retrospectively reviewed MR images of 96 patients with ...

Solid-pseudopapillary tumor (SPT) of the pancreas is characterized as cystic, necrotic, and hemorrhagic degeneration. In this study, magnetic resonance (MR) findings of 4 cases were reviewed. Patchy or spotty areas of high intensity that suggested hemorrhagic degeneration were constantly detected on fat-suppressed T(1)-weighted images. Dynamic contrast-enhanced MR imaging revealed mild ...

Two of the strongest tools to manipulate visual awareness of potentially salient stimuli are binocular rivalry and dichoptic masking. Binocular rivalry is induced by presenting incompatible images to the two eyes over prolonged periods of time, leading to an alternating perception of the two images. Dichoptic masking is induced when ...

PURPOSE: To determine the appropriate concentration for quantitative assessment of dynamic contrast-enhanced pulmonary MR imaging. MATERIALS AND METHODS: A total of 40 consecutive patients with small bronchioalveolar carcinoma underwent perfusion single-photon emission tomography (SPECT) and three-dimensional (3D) dynamic MR imaging with a 3D radiofrequency spoiled gradient-echo sequence. In each patient, ...

BACKGROUND: Dynamic telepathology is the real-time transmission of histologic images from one pathologist to another by means of telecommunications technology. OBJECTIVE: The objective was to determine whether dynamic telepathology can be accomplished accurately and inexpensively by use of readily available off-the-shelf consumer products and software. METHODS: We attached a standard, ...

BACKGROUND: Dynamic positron emission tomography studies produce a large amount of image data, from which clinically useful parametric information can be extracted using tracer kinetic methods. Data reduction methods can facilitate the initial interpretation and visual analysis of these large image sequences and at the same time can preserve important ...

Pelvic magnetic resonance is a simple and non-invasive imaging technique for dynamic and static assessment of the pelvic floor. The morphology of the support system is assessed by T2-weighted images. Dynamic sequences are used to assess pelvic prolapse. In this study we illustrate the normal and pathologic features of the ...

Reference tissues are currently used to analyse dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) data. The assessment of tumour response to treatment with anti-cancer drugs is a particularly important application of this type of analysis and requires a measure of reproducibility to define a level above which a significant change due ...