T2 Relaxation Value Research Articles

Changes in the T2 relaxation value of the tibiofemoral articular cartilage about 6 months after anterior cruciate ligament reconstruction using the double-bundle technique

Changes in the T2 relaxation value of the tibiofemoral articular cartilage about 6 months after anterior cruciate ligament reconstruction using the double-bundle technique

Quantitative serial T2 relaxometry: a prospective evaluation in solitary cerebral cysticercosis.

We describe the evolution of quantitative T2 relaxometry values on serial MRI in patients with a solitary cerebral cysticercal lesion (SCCL), and determine whether albendazole therapy affects T2 relaxation (T2R) values. Patients with new-onset seizures and MRI-confirmed SCCL were randomized to treatment with albendazole and antiepileptics ("treatment group") or antiepileptics only ("controls"). Serial MRI including T2 relaxometry was performed at baseline, three, six, 12, and 24 months. Of 123 patients recruited, 81 had more than three MRI scans (treatment group: 37; controls: 44; 58 patients had five scans). The lesion wall at baseline showed a mean T2R value of 152.3 ms, centre 474.9 and perilesional parenchyma 338.5 ms. These were significantly higher than those from normal parenchyma (114 ms). Over time, most sharply in the initial three months, T2R values fell but even at 24 months, they remained above those from normal parenchyma. A slight increase in T2R values from the lesion centre at six months was thought to represent the initiation of gliosis. In the treatment group, T2R values approached normal at 24 months, while controls had persistently higher T2R values. The decline in T2R values at six months was more prominent in the treatment group. T2R values at baseline and at three months differed significantly depending on the stage of the lesion, being higher in stage 2 SCCL. T2R values from SCCL declined over 24 months, being significantly higher in earlier stages of degeneration. A mild increase after six months may be due to the initiation of gliosis. T2R values appear to decline faster in patients who receive albendazole.

Diffusion tensor imaging and T2 relaxometry of bilateral lumbar nerve roots: feasibility of in‐plane imaging

Lower back pain is a common problem frequently encountered without specific biomarkers that correlate well with an individual patient's pain generators. MRI quantification of diffusion and T2 relaxation properties may provide novel insight into the mechanical and inflammatory changes that occur in the lumbosacral nerve roots in patients with lower back pain. Accurate imaging of the spinal nerve roots is difficult because of their small caliber and oblique course in all three planes. Two-dimensional in-plane imaging of the lumbosacral nerve roots requires oblique coronal imaging with large field of view (FOV) in both dimensions, resulting in severe geometric distortions using single-shot echo planar imaging (EPI) techniques. The present work describes initial success using a reduced-FOV single-shot spin-echo EPI acquisition to obtain in-plane diffusion tensor imaging (DTI) and T2 mapping of the bilateral lumbar nerve roots at the L4 level of healthy subjects, minimizing partial volume effects, breathing artifacts and geometric distortions. A significant variation in DTI and T2 mapping metrics is also reported along the course of the normal nerve root. The fractional anisotropy is statistically significantly lower in the dorsal root ganglia (0.287 ± 0.068) than in more distal regions in the spinal nerve (0.402 ± 0.040) (p < 10(-5) ). The T2 relaxation value is statistically significantly higher in the dorsal root ganglia (78.0 ± 11.9 ms) than in more distal regions in the spinal nerve (59.5 ± 7.4 ms) (p < 10(-5) ). The quantification of nerve root DTI and T2 properties using the proposed methodology may identify the specific site of any degenerative and inflammatory changes along the nerve roots of patients with lower back pain.

Age‐related regional brain T2‐relaxation changes in healthy adults

To determine normal T2-relaxation values from different brain areas in healthy adults, assess age-related T2-relaxation changes in those sites, and evaluate potential gender-related T2-relaxation value differences. We performed proton-density and T2-weighted imaging in 60 healthy adults (male: 38, age range = 31-64 years, mean age ± SD = 46.1 ± 9.3 years; female: 22, age range = 37-66 years, mean age ± SD = 49.5 ± 8.3 years), using a 3.0 Tesla MRI scanner. T2-relaxation values were calculated voxel-by-voxel from proton-density and T2-weighted images, and whole-brain T2-relaxation maps were constructed and normalized to a common space. A set of regions-of-interest were outlined within the basal ganglia, limbic, frontal, parietal, temporal, occipital, thalamic, hypothalamic, cerebellar, and pontine regions using mean background images derived from normalized and averaged T2-weighted images of all individuals, and regional T2-relaxation values were determined from these regions-of-interest and normalized T2-relaxation maps. Pearson's correlations were calculated between T2-relaxation values and age, and male-female differences evaluated with independent-samples t-tests. T2-relaxation values typically increased with age in multiple brain sites; only a few regions showed declines, including the putamen and ventral pons. Sex-related differences in T2-relaxation values appeared in basal ganglia, frontal, temporal, occipital, and cerebellar regions; males showed higher values over females in these sites. Establishment of normative adult T2-relaxation values over different brain areas, with age and sex as co-factors, offers baseline values against which disease-related tissue changes can be assessed.

Uterine cervical punch biopsy specimens can be analyzed by 1h mrs

Biopsy specimens of the uterine cervix, including colposcopically directed punch biopsy specimens of females with atypical Papanicolaou smear tests, are suitable for analysis by magnetic resonance (MR) spectroscopy. A narrow lined lipid MR spectrum, characteristic of malignant tissue, is obtained from a 6-mm3 biopsy specimen of histologically confirmed squamous carcinoma of the cervix. In contrast, specimens containing inflammatory cells generate a broad component only centered at 1.3 ppm with a T2 relaxation value of less than 350 ms. Most biopsy specimens which contain dysplastic cells or evidence of human papilloma virus (HPV) infection have a discernible lipid spectrum similar to that of the malignant tissue specimen. Long T2 relaxation values found in malignant tissue specimens at 1.3 and 1.2 ppm are observed in some but not all of the biopsies which show evidence of HPV infection. The suitability of small tissue samples, such as punch biopsy specimens, for study by MR illustrates the sensitivity of this technique and its potential as an aid to histopathological discrimination between the various precursor states of cervical cancer.

Inhibition of metastatic potential by fucosidase: an NMR study identifies a cell surface metastasis marker.

NMR spectroscopy is able to detect subtle changes to the surface chemistry of cells. We have previously shown that high-resolution 1H NMR methods can identify tumor cells with the capacity to metastasize, and we now report that the long T2 relaxation value (500-800 ms) observed in metastatic rat mammary adenocarcinoma cells is removed by treatment with fucosidase. Two-dimensional scalar-correlated NMR (COSY) spectra of fucosidase-treated cells show that a cross peak, consistent with scalar coupling between the methyl and methine groups on fucose and usually associated with malignancy and metastatic ability, is absent. Metastases were observed in only two out of ten rats injected subcutaneously with enzyme-treated cells compared to eight out of ten with untreated cells. NMR studies on isolated cellular lipids identified the long T2 relaxation value only in the ganglioside fraction. This fraction accounts for 51% of the total 14C-labelled fucose incorporated into the cells. We propose that fucogangliosides are an indicator of metastatic potential in rats. The observation that a cell surface metastasis marker has an NMR signal with a characteristically long relaxation value has important consequences for the future use of magnetic resonance imaging and spectroscopy in the cancer clinic.