mri constrast

BACKGROUND: Gadolinium-based contrast agents are commonly used in brain magnetic resonance imaging (MRI), however, they cannot be used by patients with allergic reactions or poor renal function. For long-term follow-up patients, gadolinium deposition in the body can cause nephrogenic systemic fibrosis and other potential risks. PURPOSE: Developing a new method of enhanced image synthesis based on the advantages of multisequence MRI has important clinical value for these patients...

INTRODUCTION: Synovial sarcomas occurring as primary nerve tumors (SSPN) are rare and only 69 cases of SSPNs are reported in literature. Despite the little data available, SSPNs differ from other SSs in some distinctive aspects such as epidemiology, location, and early onset of symptoms. SSPN are consequently underdiagnosed and easily mistaken for benign or malignant peripheral nerve sheath tumors (PNST). Therefore, cytogenetic or molecular testing becomes essential in order to make a correct diagnosis...

Magnetic resonance imaging (MRI) is a non-invasive imaging technology to diagnose health conditions, showing the weakness of low sensitivity. Herein, we synthesize a contrast agent, SPIO@SiO2 @MnO2 , which shows decreased T1 and T2 contrast intensity in normal physiological conditions. In the acid environment of tumor or inflamed tissue, the manganese dioxide (MnO2 ) layer decomposes into magnetically active Mn2+ (T1 -weighted), and the T1 and T2 signals are sequentially recovered. In addition, both constrast quenching-activation degrees of T1 and T2 images can be accurately regulated by the silicon dioxide (SiO2 ) intermediate layer between superparamagnetic iron oxide (SPIO) and MnO2 ...

BACKGROUND: Cutaneous Central Follicular Lymphoma (CCFL) is a Type B cutaneous lymphoma with a usually indolent course. Scalp localization of CCFL is extremely rare, we report a new case mimicking an epidural hematoma, and showing a rapid progression with aggressive infiltration of skin, calvaria, dura and brain parenchyma. CASE REPORT: A 58-year-old patient with an unlabeled polymalformative syndrome was admitted to the Emergency department following a head injury secondary to a self-resolving tonic-clonic epileptic seizure...

Different magnetic resonance imaging pulse sequences are used to generate image contrasts based on physical properties of tissues, which provide different and often complementary information about them. Therefore multiple image contrasts are useful for multimodal analysis of medical images. Often, medical image processing algorithms are optimized for particular image contrasts. If a desirable contrast is unavailable, contrast synthesis (or modality synthesis) methods try to "synthesize" the unavailable constrasts from the available ones...

Superparamagnetic iron oxide nanoparticles (SPION) have received immense interest for biomedical applications, with the first clinical application as negative contrast agent in magnetic resonance imaging (MRI). However, the first generation MRI contrast agents with dextran-enwrapped, polydisperse iron oxide nanoparticle clusters are limited to imaging of the liver and spleen; this is related to their poor colloidal stability in biological media and inability to evade clearance by the reticuloendothelial system...

To describe cerebral (structural and functional MRI) and neuropsychological long term changes in moderate drowning victim's compared to healthy volunteers in working memory and motor domains. We studied 15 adult drowning victim's in chronic stage (DV - out of 157 eligible cases of sea water rescues with moderate drowning classification) paired to 18 healthy controls (HC). All participants were investigated using intelligence, memory, and attention neuropsychological standard tests and underwent functional (motor and working memory tasks) and structural magnetic resonance imaging (MRI) in a 3 T system...

PURPOSE: To describe the internal pudendal artery (IPA) and accessory pudendal artery (APA) detected by magnetic resonance (MR) angiography to help surgeons to find and preserve them during radical prostatectomy (RP). MATERIALS AND METHODS: Constrast-enhanced MR 3.0 T angiography of the pelvis were performed in 111 male patients suspected diagnosis of prostate cancer (PCa), and describe the penile arterial blood supply. RESULTS: There are three patterns of the arterial blood supply to the penis (IPA and/or APA) accounting for 51...

BACKGROUND: This is a prospective study to evaluate the role of CINE MRI to predict obstructive hydrocephalus in the preoperative work-up. PATIENTS/MATERIAL AND METHODS: A total of 16 patients with aqueductal obstruction demonstrated by CINE MRI who were undergoing ETV were included. MRI was performed preoperatively, at 3 months, at 12 months and at 24 months after surgery. Prior to the fenestration of the third ventricular floor aqueductal patency was evaluated using intraoperative ventriculography...

Nanomaterials offer new opportunities for cancer diagnosis and treatment. Multifunctional nanoparticles harboring various functions including targeting, imaging, therapy, and etc have been intensively studied aiming to overcome limitations associated with conventional cancer diagnosis and therapy. Of various nanoparticles, magnetic iron oxide nanoparticles with superparamagnetic property have shown potential as multifunctional nanoparticles for clinical translation because they have been used asmagnetic resonance imaging (MRI) constrast agents in clinic and their features could be easily tailored by including targeting moieties, fluorescence dyes, or therapeutic agents...

BACKGROUND AND OBJECTIVE: Brain metastases are a common complication of lung cancer, occurring in 20%-40% of patients. The aim of this study is to explore prognostic factors in non-small cell lung cancer (NSCLC) in patients with brain metastases diagnosed by constrast-enhanced MRI after whole brain radiotherapy. METHODS: TA retrospective review of clinical data from 241 NSCLC patients with brain metastases received whole brain radiotherapy from April 2007 to October 2008 was performed...

The water-exchange reaction in two diastereoisomers of the clinical magnetic resonance imaging contrast agent [Gd(HP-DO3A)(H(2)O)] (also known as ProHance) has been studied using ab initio simulations. On the basis of the molecular-level details of the mechanism derived from these simulations in aqueous solution, we unravel the underlying difference in the free energies and mechanisms of water exchange in the two diastereoisomers. These findings reveal the crucial role played by hydrogen-bonding dynamics and thus suggest their appropriate control in tailoring improved gadolinium-based constrast agents...

Bile acid-conjugated gadolinium chelates were shown to display promising features for the development of hepatospecific constrast agents for magnetic resonance imaging (MRI). The study of the pharmacokinetics of these compounds should address their possible interaction with the bile acid protein transporters. We have previously shown that a 5beta-cholanoic acid-based contrast agent is efficiently internalized in hepatocytes and is able to bind to a liver bile acid binding protein (BABP) in vitro. Here we report the solution structure of the adduct between a BABP and a gadolinium chelate/bile acid conjugate...

OBJECTIVE: To describe the characteristic magnetic resonance imaging (MRI) appearance of cerebral schistosomiasis. METHODS: Twenty-five patients whose diagnosis of central nervous system (CNS) schistosomiasis had been pathologically (n = 8) and clinically (n = 17) confirmed were randomly selected. MRI was performed on a Signal 1. 5T MRI scanner before and after the intravenous administration of gadopentetate dimeglumine constrast medium. We reviewed the MRI studies obtained at the time of initial presentation, as well as follow-up studies obtained during and after medical treatment...

Fluid attenuated inversion recovery (FLAIR) sequences produce selective cerebrospinal fluid (CSF) suppression by employing a very long inversion time (TI). We used the FLAIR sequence to study patients with multiple sclerosis (MS) at 0.6 T. So far, a very long TR (and long acquisition time) has been used in a fully relaxed (FR-FLAIR) system. To speed up the FLAIR sequences, we used a shorter TR, and demonstrated that complete CSF suppression can be maintained with partial saturation (PS-FLAIR) by reducing TI at the same time...