Relaxometry Research Articles

The potential role of magnetic resonance brain relaxometry in veterinary medicine: a preliminary study.

Magnetic Resonance (MR) is a non-invasive modality of choice for the evaluation of brain morphology, with superior performance as compared to other techniques. However, MR images are typically assessed qualitatively, thus relying on the experience of the involved radiologist. This may lead to errors of interpretation in the presence of subtle alterations and does not exploit the full potential of this technique as a quantitative diagnostic tool. To this end Magnetic Resonance Relaxometry (MRR), which is able to quantitively characterize the tissues under investigation through their relaxation rates, seems extremely promising. Many studies assessed the feasibility of relaxometry as a diagnostic tool in human brain disorders, with the most promising results obtained in the evaluation of neurodegenerative diseases and in the oncologic field. However, despite such extensive literature in human medicine, due to the lack of standardized protocols and the need of high-field MRI scanners, to date few studies have been performed on companion animals. In this work, first we describe relaxometry applications in human neuropathology and their possible extension to companion animals both in the experimental and clinical fields. Then, we present two experiments performed on a typical standard clinical scanner operating at 0.25 T to show that, despite the low field intensity, this technique may be promising even in the clinical setup. We tested the relaxometry protocol in a phantom study and then applied it to a real clinical case study. The results showed that this protocol used on a phantom led to a higher contrast, as compared to the standard approach. Furthermore, when applied to a real case study, this protocol revealed brain lesions undetected by the standard technique which were confirmed by a histopathological examination. These preliminary results are encouraging and support the development of this approach as an advanced diagnostic tool even in a clinical setting where low field MRI scanners are typically employed.

Quantitative Magnetic Resonance T2 Relaxometry Imaging of Knee Joint Tibia & Femoral Articular Cartilage

Background: The knee joint is the largest synovial joint in the body with multiple articulating surface. The major consists of the articulation between the femur and tibia, which is weight bearer of the whole body weight and for the balance; and this articulation surface has a major chance of breakdown easily due to various reasons. MR imaging is a powerful tool for the morphologic and compositional imaging of cartilage in the knee for the detection of early cartilaginous degeneration and increased utility for the assessment of cartilage repair techniques. Aim: To obtain T2 relaxometry value of knee joint tibia and femoral articular cartilage & to compare the T2 relaxometry values of the early Osteoarthritic patients with that of the other cause. Material & Methods: 20 patients who presented themselves in Radiology department of either sex whose reports and image data’s are collected prospectively during the study period of December 2011 to February 2012. All the patients’ data within the study period were collected. Patients were selected irrespective of their age group, gender and pathologic findings, a detailed history with various patient’s data includes patient demography, age, sex and the study reports are collected and is entered in a specially designed Profoma. The acquired study data of Sagittal T2 Mapping High Resolution sequence of each patient are then post processed by using a GE Advantage Workstation (version 4.4) and T2 Relaxometry values of various knee joint cartilages (Medial & Lateral femoral and tibial cartilage) are collected by using a special software and is entered in the table. Conclusion: Conventional MRI may not show early cartilage changes; Cartilage edema following trauma (or) Due to osteoarthritis can be picked up early by T2 Mapping. hence it is useful in early patient management. Key words: MRI, Knee joint imaging, tibia and femoral cartilage Imaging, Joint cartilage, T2 Relaxometry, T2 Mapping, osteoarthritis, Knee trauma, Medial and Lateral Tibia and Femoral Cartilage.

Diffusion of liquids in confined media: a field cycling relaxometry approach

On montre que la mesure des variations des vitesses de relaxation spin-reseau avec le champ magnetique ou la frequence de Larmor permet de caracteriser directement la dynamique des liquides confines. Cette methode est appliquee pour mesurer les coefficients de diffusion de translation de differents liquides aprotiques et de l'eau confinee dans les nanopores de systemes calibres. La methode est etendue a des systemes macropororeux plus complexes comme les empilements granulaires, les roches petroliferes et les ciments.

Relaxometry of Dextran and Albumin Labeled with Gd-Chelates

Relaxometry of Dextran and Albumin Labeled with Gd-Chelates