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Background: Previous literature demonstrated that the T2* value of the uterine junctional zone was lower than that of peripheral myometrium by using BOLD MR imaging. We expect T2* mapping image may add more information to T2-weighted images of the uterine myometrium. Purpose: To evaluate whether T2* mapping software would reproduce the result of previous report, and to apply the software to benign uterine diseases. Material and Methods: Five healthy volunteers and 19 patients clinically suspected of having benign pelvic disease were imaged using a 1.5T MR system. All women were of reproductive age, and all provided informed consent. Sagittal T2* images using a multishot EPI sequence were obtained. T2* values were calculated and color T2* maps reconstructed using a T2* fitting tool. Results: The uterine zones could be identified in all 24 examinations on the T2* maps. In addition, a thin "4th zone" was seen between the endometrium and the JZ (junctional zone) in 19 of 24 examinations. The T2* value of JZ was significantly lower than that of peripheral myometrium (PM) (P < 0.001). No significant difference in the T2* value of the JZ or of PM was noted between normal uterus and uterus with leiomyomas and/or adenomyosis. Conclusion: A quantitative T2* map can easily be obtained using the PRIDE software T2* fitting tool, and the software reproduces the result from previous report. T2* value of the junctional zone was lower than that of peripheral myometrium regardless of having benign myometrial diseases. [ABSTRACT FROM AUTHOR]

Background: Non-invasive MR imaging is expected to be used for accurate diagnosis and quantification of non-alcoholic steatohepatitis (NASH), because NASH is a progressive fatty liver disease. New MR techniques, such as fat fraction ratio (FFR) and T2* value measurement, have attracted an increasing attention, because those techniques can measure quantitative parameters of fibrosis, fat and iron deposition in the liver.Purpose: To investigate the potential of FFR and T2* value in NASH with pre-enhancement, gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) or super-paramagnetic iron oxide (SPIO)-enhanced MRI.Material and Methods: Twenty-eight rats were divided equally into four groups (one control group and three NASH groups). All rats underwent unenhanced, Gd-EOB-DTPA, and SPIO-enhanced MRI. The T2* value of the liver was measured for each image sequence, and then changes in T2* values before and after each injection were analyzed using Dunnett's test. The reduction rate of T2* value before and 13 min after injection of Gd-EOB-DTPA or SPIO was analyzed using Mann-Whitney's U test. Moreover, FFR of the liver was measured before enhancement, and the relationship between fat fraction and the calculated fat area percentage on a pathological specimen was examined using Spearman's correlation test.Results: On pre-enhancement, FFR and T2* value were 26.0% ± 12.0% and 21.5 ± 4.2 ms for all NASH groups, and 0.9% ± 0.5% and 30.8 ±-5.5 ms for control, respectively. Both FFR and T2* values were significantly different between the NASH and control groups. The reduction rate of T2* value was significantly lower in the NASH groups than in the control group on SPIO-enhanced MRI, though there was no significant difference on Gd-EOB-DTPA-enhanced MRI. FFR was correlated with the calculated fat area percentage for the pathological specimen.Conclusion: Pre-enhancement FFR, T2* value measurement and reduction rate of T2* value on SPIO-enhanced MRI may help estimate the progress of liver fat deposition and fibrosis in NASH. [ABSTRACT FROM AUTHOR]

We have occasionally seen ring-shaped lateral ventricular nodules <1 cm in diameter during routine brain magnetic resonance imaging (MRI). We investigated retrospectively clinical and MRI findings of the nodules. Review of radiological records was performed for 39,607 patients who underwent brain MRI between January 2001 and April 2008. Nodules were assessed for number, location, shape, and signal intensity, which was determined based on the range of signal intensity from gray to white matter on T1- and T2-weighted imaging. Fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging (DWI), contrast enhancement characteristics, and serial MRI changes of nodules were assessed when available. Nine of 39,607 patients (0.023%) showed the nodules. No symptoms associated with the nodules. Among the nine patients, 11 nodules were identified (one nodule in seven patients (77.8%) and two nodules in two patients (22.2%)). Location was limited to the roof of the body for six nodules (54.5%) and the frontal horn for five patients (45.5%). All nodules (100%) were round and isointense on T1- and T2-weighted imaging. On FLAIR imaging of eight nodules, six (75%) were hyperintense, and two (25%) were isointense. On DWI of seven nodules, all nodules (100%) were isointense. None of seven nodules (0%) examined using postcontrast MRI showed enhancement. None of eight nodules (0%) examined using serial MRI (range, 4–60 months) showed changes in morphology over time. These nodules were incidentally encountered and shared similar MRI features. Although pathological confirmation was lacking in our cases, these nodules may be of nonaggressive nature. [ABSTRACT FROM AUTHOR]

Myomectomy is a good indication for women with uterine leiomyoma who desire to preserve their child-bearing potential. However, there are still no reports about how long it takes the uterus to reach a stable state after myomectomy. We evaluated the changes in uterine structure during the recovery process after myomectomy by MR images. MR images were used to analyze the time-dependant changes in the length of the uterine cavity, the volume of the uterus, recovery of the junctional zone, prevalence of modification of the endometrium, and uterine structure in the region of the enucleated myoma. The cavity length and the volume of the uterus, and the myometrium were stabilized at six weeks after the myomectomy. With regard to the endometrium, 12 weeks were required for it to achieve a stable state after myomectomy. However, even at 12 weeks postoperatively, 14.2% of the cases showed an unusual view near the uterine incision on MR images. We concluded that the recovery process is complete at 12 weeks after the operation if there are no clear findings of hematoma or edema formation in the myometrium on MR images. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Estimating pharmacological efficacy is important when selecting conservative treatment of uterine leiomyoma. Hence, the ability of magnetic resonance (MR) imaging to predict gonadotrophin-releasing hormone (GnRH) analogue efficacy was investigated.Methods: A total of 85 lesions was studied in 40 patients who were clinically diagnosed as having uterine leiomyoma and treated with GnRH analogue for 24 weeks. To evaluate changes in lesion size, T2-weighted and gadopentetate-dimeglumine (Gd-DTPA)-enhanced, T1-weighted MR images were obtained within 2 weeks before, and immediately after termination of, GnRH analogue treatment.Results: An average 46.3% size reduction was observed in 45 lesions (52.9%); these were seen as low signal intensity on T2-weighted images and enhanced by Gd-DTPA. Also, an average 44.7% size reduction was observed in lesions enhanced by Gd-DTPA, irrespective of signal intensity findings on T2-weighted images. The average size reduction of unenhanced lesions was only 17.8%, and significantly different from enhanced lesions (P < 0.001). The prediction of efficacy was difficult in those lesions not enhanced.Conclusions: It is considered that evaluation of MR signal intensities, and the presence or absence of Gd-DTPA enhancement, would predict treatment efficacy before GnRH analogue administration. [ABSTRACT FROM AUTHOR]

We evaluated the usefulness of magnetic resonance imaging (MRI) for assessing the response of patients with endometriomas to medical therapy. MRI was performed before and after treatment in 20 consecutive patients with at least one endometrioma with a maximal diameter >10 mm diagnosed by laparoscopy who received 900 microg of buserelin acetate daily for 6 months. Patients were categorized as good responders (group I, n = 13) and poor responders (group II, n = 7) depending on the results of a third-look laparoscopy performed 6 months after treatment. We determined the ratio of the signal intensity (SI) of the endometrioma to the SI of the gluteus maximus muscle on T2-weighted images [T2SI/M (muscle) SI] and the volume of the endometrium. The volume decreased by >50% in 61.5% of the good-response group and 57.1% of the poor-response group. There was no significant difference between the two groups. The T2SI/MSI decreased in 12 of 13 patients in group I but in only one of seven patients in group II, a significant difference (P < 0.05) between the two groups. In the good-response group, there was a positive linear correlation between the decrease in the volume of the endometrioma and the decrease in the T2SI/MSI after treatment (r = 0. 561, P < 0.05). Therefore, the T2SI/MSI determined from MR images may be useful in assessing the therapeutic response of patients with endometriomas. [ABSTRACT FROM AUTHOR]