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Primary paraovarian cancer is a rare tumor occurring in the female pelvis. Magnetic resonance imaging features of paraovarian cancer have not been previously reported. In the present report, we describe a case of paraovarian cancer coexisting with cancer of the fallopian tube and the magnetic resonance features.

Purpose: To assess the possibility of differentiating between completely hyalinized leiomyomas and ordinary leiomyomas by using diffusion-weighted (DW) magnetic resonance imaging (MRI) (DWI) employing very small b-factors (b = 1.51 and 55.3 seconds/mm(2)) in comparison with three-phase dynamic MRI., Materials and Methods: The subjects were 25 patients with 52 histopathologically confirmed uterine leiomyomas. All leiomyomas were divided into two histopathologic subtypes (5 completely hyalinized leiomyomas and 47 ordinary leiomyomas). For each leiomyoma, the enhancement index (EI) at three-phase dynamic MRI and apparent diffusion coefficient (ADC) were obtained and then compared., Results: The EIs at second and third dynamic phases clearly differentiated the two types of leiomyomas without overlap of values. ADCs also clearly differentiated the two types of leiomyomas without overlap of values. Moreover, there were significant positive correlations between ADCs and EIs at all dynamic phases (r = 0.41-0.50, P < 0.01)., Conclusion: Not only three-phase dynamic MRI but also DWI with very small b-factors could be useful for differentiating completely hyalinized leiomyomas from ordinary leiomyomas., (Copyright 2004 Wiley-Liss, Inc.)

Objective: To assess the diagnostic accuracy of MR imaging for detecting bone marrow infiltration by malignant lymphoma., Patients and Design: Fifty-three patients with malignant lymphoma underwent MR imaging and bone marrow biopsy. In 80 iliac crests of the 53 patients (13 positive specimens in 9 patients and 67 negative specimens in 44 patients), biopsy results and the signal intensity characteristics were compared. MR sequences included T1-weighted SE, T2-weighted FSE with fat suppression, FSE STIR, and diffusion-weighted EPI with fat suppression at 1.5 T., Results and Conclusions: To detect lymphoma infiltration, T1-weighted SE had the highest sensitivity (92%) and diffusion-weighted EPI with fat suppression and FSE STIR had the highest specificity (92.5% and 92%, respectively). A combination of T1-weighted SE and FSE STIR yielded the highest sensitivity and specificity (85% and 97%, respectively). A combination of T1-weighted SE and FSE STIR sequences seems to be the current choice of imaging protocol for detecting bone marrow infiltration by malignant lymphoma.

Purpose: Because of the recent innovative growth in computer technology, digital imaging, and the Internet, we can take advantage of these facilities for education and clinical work in nuclear medicine. We developed a tele-nuclear medicine conference system with electronic mail (e-mail) on the Internet., Methods: Twenty-one physicians (20 radiologists, 1 neurologist), 6 technologists and 2 medical students in six university hospitals (Japan 5, Canada 1), 5 local hospitals in Japan participated in this project. We used digital still cameras (330 k pixels) equipped with a floppy disk drive and 10 x optical zoom to digitize images with JPEG compression (640 x 480 matrix). The images were attached to e-mail messages (containing a brief description of each case). The mail was sent simultaneously to all members on the mailing list. Scintigram and SPECT images as well as other radiological images were sent by e-mail. Reply mails about each case were sent to all members via the mailing list., Results: During a period of 6 months, 18 cases (tumor/infection: 7, bone: 6, cardiovascular: 1, neurology; 3, endocrine: 1) with 144 e-mails (average 5.6/case) were submitted to the conference. The average period of discussion was 15.6 days. The number of attached images was 1 to 9 (average, 4.2/e-mails). JPEG compression rate was 1/10 to 1/20. The quality of the images was good enough for discussion. Some cases required additional images for further discussion., Conclusion: Our tele-nuclear medicine conference with an electronic mailing list and digital camera was simple and low-cost. The conference system was useful for education and clinical work.

The purpose of this study was to determine the relationship between the apparent diffusion coefficient (ADC) measured on intravoxel incoherent motion (IVIM) echo-planar magnetic resonance imaging (MRI) and salivary gland function. Twenty-one patients with head and neck malignancies underwent MRI and salivary gland scintigraphy before and after radiotherapy. Based on the scintigraphic results, each major salivary gland was classified into two groups (dysfunctional and functional) and ADCs measured on IVIM MRI were compared between the two groups. Furthermore, the relationship of ADC to scintigraphic parameters, maximum accumulation (MA), and the uptake ratio (UR), were analyzed. ADCs of the dysfunctional group decreased significantly after radiotherapy (P <.01), whereas those of the functional group showed no significant change. Furthermore, positive correlations were found between the ADC ratio and both MA (P <.005) and UR (P <.001). ADC measurement on IVIM echo-planar MRI is a potentially useful means of evaluating salivary gland function., (Copyright 2001 Wiley-Liss, Inc.)

This study was performed to determine if there is a relationship between apparent diffusion coefficient (ADC) and cellularity of bone marrow of the posterior ilium. Four groups of various marrow cellularity underwent diffusion-weighted echo-planar imaging: 1) adults with normal hypocellularity (21 patients); 2) adults with normal normocellularity (13 patients); 3) young children with normal hypercellularity (5 patients); and 4) adults with lymphoma-related hypercellularity (3 patients). In all adults, marrow cellularity was confirmed by uni-or bilateral bone marrow biopsies. In children, the iliac marrow was presumed hypercellular because of their ages. A total of 66 ADC values of bone marrow calculated from diffusion-weighted images with b-values of 30 and 300 seconds/mm(2) was evaluated. Hypercellular marrow (normal and lymphoma-related) showed the highest mean ADC, and hypocellular the lowest ADC. Statistically significant differences were found between three groups of normal marrow: hypocellular, normocellular, and hypercellular. There is a positive correlation between ADC and cellularity of bone marrow. J. Magn. Reson. Imaging 2001;13:757-760., (Copyright 2001 Wiley-Liss, Inc.)

We reported a case of asymptomatic pancreatic AVM, incidentally found on routine ultrasonography and diagnosed noninvasively by means of Doppler ultrasonography and MRI. The diagnosis was confirmed by angiography. This is the first report to demonstrate the characteristics of pancreatic AVM by these two imaging techniques. They proved to be useful in identifying the vascular nature of AVM without the use of a contrast material, which is a definite advantage over DSA and CT. The quality of the image obtained was equivalent or superior to that obtained by DSA and contrast-enhanced CT. Doppler ultrasonography and MRI may serve as the primary imaging techniques of choice in suspected cases of AVM.