Study of techniques and postprocessing for ~(31)P MRS of human bone and soft tissue / 医疗卫生装备

Objective To investigate the best techniques and postprocessing protocols for 31P MRS of femur and soft tissue.Methods The 31P MRS was performed on the 20 normal volunteers,using Siemens SONATA 1.5T MR scanner and heart/liver 31P surface coil.The age of volunteers ranged from 18 to 25 years old.Related data came from 40 voxels of the interested region were post-processed and compared by two different kinds of methods: automatically processed(group A) and interactively processed(group B).Results In group A,only 28 of 40 studies displayed well defined spectra,another 12 can't,and the shift of PCr deviated from 0.0 ppm;In group B,35 of 40 studies produced well defined spectra,another 5 can't,and the shift of PCr was near to 0.0 ppm,(p

Human in-vivo 31P MR Spectroscopy of Benign and Malignant Breast Tumors

OBJECTIVE: To assess the potential clinical utility of in-vivo 31P magnetic resonance spectroscopy (MRS) in patients with various malignant and benign breast lesions. MATERIALS AND METHODS: Seventeen patients with untreated primary malignant breast lesions (group I), eight patients with untreated benign breast lesions (group II) and seven normal breasts (group III) were included in this study. In-vivo 31P MRS was performed using a 1.5 Tesla MR scanner. Because of the characteristics of the coil, the volume of the tumor had to exceed 12 cc (3 x 2 x 2 cm), with a superoinferior diameter at least 3 cm. Mean and standard deviations of each metabolite were calculated and metabolite ratios, such as PME/PCr, PDE/PCr, T-ATP/PCr and PCr/T-ATP were calculated and statistically analyzed. RESULTS: Significant differences in PME were noted between groups I and III (p=0.0213), and between groups II and III (p=0.0213). The metabolite ratios which showed significant differences were PME/PCr (between groups II and III) (p=0.0201), PDE/PCr (between groups I and III, and between groups II and III) (p=0.0172), T-ATP/PCr (between groups II and III) (p=0.0287), and PCr/T-ATP (between groups II and III) (p=0.0287). There were no significant parameters between groups I and II. CONCLUSION: In-vivo 31P MRS is not helpful for establishing a differential diagnosis between benign and malignant breast lesions, at least with relatively large lesions greater than 3 cm in one or more dimensions.

Myocardial Protection of Lidocaine in Acute Ischemia-Reperfusion : A 31P MR Spectroscopic Study in Cats

BACKGROUND: Lidocaine is a well known antiarrhythmic agent. However, recent reports indicate that indocaine has myocardial protective effects on acute myocardial ischemia and reperfusion. The exact mechanism of myocardial protection of lidocaine is still not clearly understood. In this study we intended to assess the effects of lidocaine on high energy phosphate metabolism in cats subjected to myocardial ischemia-reperfusion by using 31P MR spectroscopy. Effect of lidocaine on size of infarct will also be evaluated by 2, 3, 5-triphenyltetrazolium chloride(TTC) staining. METHODS: Twenty-seven cats were used for this study. The animals were divided into three groups : for group 1(n=10) and group 2(n=7), animals were subjected to a 90 min of LAD occlusion followed by a 90 min of reperfusion ; for group 3(n=10), a 20 min of occlusion followed by a 90 min of reperfusion. In group 2 and group 3, lidocaine(5mg/kg/hr) was infused continuously during the occlusion and reperfusion periods with an initial bolus injection(1mg/kg) before ligation of LAD. In-vivo MR spectroscopy was performed on a 4.7T Biospec System(Bruker, Switzerland). A home-made surface coil(diameter : 1.5cm) was used to receive31p signals from the myocardium underwent ischemic and reperfusion damage. RESULTS: Decrease of PCr during ischemic period was not different between each groups : PCr showed less than 30% of the baseline value at L-30 in group 1 and group 2 and at L-20 in group 3. More than 90% recovery of PCr was achieved at R-30 in group 2 and group 3, whereas less than 50% of PCr was recovered in group 1. Decrease of ATP during ischemic period was less pronounced in group 2 than in group 1 : in group 2 ATP depleted down to 25% of the baseline at L-90, whereas in group 1 ATP decreased to 50% of the baseline. Recovery of ATP during reperfusion period was not signiflcant in all three groups. On TTC staining, evidence of infarct was seen in all cases of group 1 : the area of infarct was 12.3+/-2.7% of the left ventricular mass and 23.9+/-6.1% of the area at risk. On the contrary, there was no evidence of infact in any case of group 2 and group 3. CONCLUSION: In this study, we found that lidocaine has myocardial protecitve effects on ischemia-reperfusion in cats. Lidocaine improves high energy phosphorous metabolism during ischemia and reperfusion as well as reduces infarct size.

Effects of 2-Deoxy-D-Glucose on Metabolic Status, Proliferative Capacity and Growth Rate of FSall Tumor: Observations made by In Vivo 31P-Nuclear Magnetic Resonance Spectroscopy and Flow Cytometry / 대한치료방사선과학회지

The effect of 2-deoxy-d-glucose (2-DDG) on C3H mouse fibrosarcoma (FSall) was studied. Metabolic status, especially for energy metabolism, was studied using in vivo 31P-MRS, proliferative capacity was observed on flow cytometry (FC) and growth rate was measured after transplantation of 106 viable tumor cells in the dorsum of foot of C3Hf/Sed mice. One gram of 2-DDG per kg of body weight was injected intraperitoneally on 12th day of implantation. Average tumor size on 12th day of implantation was 250mm3. Growth rate of FSall tumor was measured by tumor doubling time between tumor age 5-12 days was 0.84 days with slope 0.828 and tumor doubling time between tumor age 13-28 days was 3.2 days with slope 0.218 in control group. After 2-DDG injection, tumor doubling time was elongated to 5.1 days with slope 0.136. The effect of 2-DDG studied in vivo 31P-MRS suggested that the increase of phosphomonoester (PME) and inorganic phosphate (Pi) by increasing size of tumor, slowed down after 2-DDG injection. Flow cytometry showed significantly increased S-phase and G2+M phase fraction suggesting increased proliferative capacity of tumor cells in the presence of 2-DDG. Authors observed an interesting effect 2-DDG on FSall tumor and attempt to utilize as an adjunct for radiotherapy.