Search results for "MR imaging"

Neuronavigated-biopsy in the diagniosis of demyelinating pseudotumoral brain lesions. Case report.

2013

Introduction: Pseudotumoral-demyelinating lesions are typically characterized by severe difficulties in differential diagnosis from gliomas, metastatic tumors and abscesses. Marburg’s disease (MD) is an extremely rare and aggressive form of Mutiple Sclerosis (MS) with acute onset, rapid neurological deterioration, and poor prognosis. MRI images often show pseudotumoral lesions characterized by mild and focal or, sometimes, ring enhancement. Perhaps, radiological aspect can vary, making necessary hystopathological confirmation. Objectives: There is increasing interest in the role of surgical biopsy for a correct and early diagnosis of pseudotumoral demyelinating lesions. We report an histopa…

Presacral Myelolipoma

2014

Many reports have described adrenal myelolipomas but there have been only a few reports of extra-adrenal myelolipomas. We describe a 74-year-old woman who came to our observation for MRI of the lumbar spine for typical lumbar back pain. In addition to signs of mild scoliosis and spondylo disc arthrosis, MR imaging revealed a presacral mass showing a heterogeneously high signal in all pulse sequences and almost completely suppressed on inversion recovery sequences for fat tissue. CT imaging confirmed the fatty nature of the lesion and no signs of bone involvement. These findings were most consistent with a diagnosis of a rare presacral myelolipoma as confirmed at histopathologic analysis. T…

Using anatomic and metabolic imaging in stereotactic radio neuro-surgery treatments

2016

Peritumoral perfusion and proton spectroscopic MR imaging in the differentiation of gliomas and solitary metastases

2015

Purpose: To asses the value of peritumoural perfusion-weighted and proton spectroscopic MR imaging in preoperative grading of gliomas and in differentiating between primary gliomas and solitary metastases. Methods and Materials: Ten low-grade gliomas, eight high-grade gliomas, and ten metastases were prospectively evaluated with MR imaging, dynamic susceptibility contrast-enhanced perfusion imaging, and single-voxel proton MR spectroscopy before surgical resection or stereotactic biopsy. Maximal rCBV values and maximal Cho/Cr ratios were calculated from peritumoural region surrounding the tumour. Tumour grade presumed with these values was compared to histopathologic grading. Differences in…

An interesting approach for the diagnosis of hepatic fibrosis: Wáng et al., “A combined use of intravoxel incoherent motion MRI parameters can differ…

2017

Since its description in 1986 by Le Bihan et al. , intravoxel incoherent motion (IVIM) diffusion MR imaging has made great progresses (1-4). Many studies demonstrated the influence of various pathologies on the diffusion parameters especially in case of cirrhosis and fibrosis. However, few of them are useful at the individual level because of the variability of IVIM values (5). It is indeed very difficult to measure precisely PF and Dfast (6,7). Many published work tried to improve the precision of the measurements, tries to better understand the diffusion patterns, improve the image acquisition sequences or image post-processing. Unfortunately, till today, the reproducibility of the IVIM d…

High-­grade gliomas and solitary metastases: differentiation by using peritumoral perfusion and proton spectroscopic MR imaging.

2013

Pigmented villonodular bursitis (PVNB) in the medial gastrocnemius bursa:report of an unusual case.

2009

INTRODUCTION: Pigmented villonodular synovitis (PVNS) represents an uncommon benign proliferative disorder that may involve the synovium of the joint diffusely or focally, or that may occur extraarticularly in a bursa (pigmented villonodular bursitis [PVNB]) or tendon sheath (pigmented villonodular tenosynovitis [PVNTS]). The knee, followed by the hip, is the most common location for PVNS or PVNB, whereas PVNTS occurs most often in the hand and foot. It primarily involves young adults, the peak age being between the second and fourth decade of life and appears with non-specific symptoms which mimic other pathologies, including traumatic knee injuries, thus often delaying the correct diagnos…

Hypogonadotrophic Pituitary Insufficiency in Transfusional Hemochromatosis Complicating Thalassemia Major: MR Imaging

1999

To identify pituitary iron overload in patients with transfusion-dependent thalassemia major causing secondary hypogonadism, we prospectively evaluated signal intensity abnormalities of the anterior lobe of the pituitary gland of 30 patients comparing spin-echo, gradient-echo imaging and pituitary T2 relaxation times measurement. We found that pituitary iron overload can best be assessed by MR imaging using gradient-echo T2*-weighted technique to establish signal reduction in the anterior lobe of the pituitary gland. This finding is correlated to increasing serum ferritin level — a parameter that reflects the severity of iron overload, and is more evident in patients with secondary hypogon…

CT and MR Imaging of Lesions of Skull Base and Cranial Vault

1989

The importance of CT in examinations of the skull base, including its role in the planning of operative or radiation therapy, has long been recognized (Liliequist and Forsell 1976; Bradac et al. 1977 a, b; 1978 a, b; Hammerschlag et al. 1977; Caille et al. 1977; Lohkamp et al. 1977; Huk and Schiefer 1978; Becker et al. 1978; Weinstein et al. 1978). In the present chapter we shall review the capabilities and limitations of this modality in the diagnosis of diseases involving the bony skull base and cranial vault. A more detailed discussion of specific tumor types may be found under the appropriate headings elsewhere in the book.

MR imaging of the lungs with hyperpolarized helium-3 gas transported by air.

2002

Hyperpolarized noble gas MRI shows promise in the functional imaging of the pulmonary air spaces. The production of hyperpolarized (HP) gas requires specialized laser optical pumping apparatus, which is not likely to be home built in the majority of clinical MRI radiology centres. There are two routes through which HP gas will be made available to hospitals for clinical use: either the apparatus will be installed locally at a considerable expense to the centre, or a central facility will produce the gas and then deliver it to remote MRI sites as and when required. In this study, the feasibility of transporting large quantities of HP gas for in vivo MR imaging from a remote production facili…