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The purpose of this study was to determine the effect of oral contrast on FDG uptake in the colon and to determine the normal distribution of FDG in the colon. Sixty patients (30 patients in no contrast group and 30 patients in the received contrast group) underwent FDG-PET/ CT scans. The pattern of FDG uptake was classified into 5 patterns (diffuse, segmental, single-nodular, multi-nodular, and other) in 5 segments (ascending, transverse, descending, and rectosig-moid colon). SUVs of the no oral contrast group were examined. The ratios of FDG uptake patterns were compared in the received contrast group and no contrast group to evaluate the effect of oral contast. The effect of attenuation correction on the uptake pattern was evaluated by comparison of the attenuation-corrected and non-attenuation-corrected PET images. In the no contrast group, there was no significant uptake in 72 segments (59%) and a diffuse pattern was seen in 29 segments (24%), most frequently in the ascending colon and descending colon. A segmental pattern was seen in 15 segments (13%), most frequently in the rectosigmoid colon. A single-nodular pattern was seen in 3 segments (3%) and multi-nodular pattern in 1 segment (1%). A nodular pattern was seen only in the ascending colon. SUVmax of the ascending colon and that of the rectosigmoid colon were significantly higher than those of the transverse and descending colon. The frequencies of diffuse, multi-nodular and ‘other’ patterns were significantly higher in the received contrast group than in no contrast group. There was no significant difference between the frequency of the segmental pattern or the single nodular pattern in the two groups. There was no significant difference between the uptake patterns with attenuation correction and those without attenuation correction in either the received contrast group or no contrast group. Normal FDG uptake in the large bowel may show various degrees and patterns of uptake among the colonic segments. Oral contrast agent can cause focal or diffuse increased FDG uptake, which may be induced not only by the high CT density of oral contrast but also by an accelerated physiologic reaction of the large bowel.

We herein report FDG-PET/CT findings of sarcomatous transformation in a patient with neurofibromatosis type 1 (NF-1). About 5% of patients with NF-1 develop sarcomatous transformation of a malignant peripheral nerve sheath tumor which arises from plexiform neurofibromas and is often associated with a poor prognosis. Morphologic imaging techniques such as Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) are the standard methods to define the anatomic extent of the tumor, although tumor heterogeneity prevents reliable differentiation between benign and malignant lesions. The degree of fluoro-deoxyglucose (FDG) uptake correlates with histologic grade in neurogenic tumors in NF-1 patients. Our patient had a huge mass in the left gluteus area with a large nearly circular focus of increased FDG uptake in the tumor. The mass had a photopenic center. The maximum Standard Uptake Value (SUVmax) of this mass was 6.6. There was CT evidence of invasion of the left iliac wing, left acetabulum, and left superior pubic ramus; however there was no increased FDG uptake in these areas on the PET study. We surmised that the high FDG uptake indicated a high grade sarcoma, which was confirmed histologically. There was also a focal region of increased uptake in the L5 vertebral body, correlating with the CT hypodense lesion, with 2.9 SUVmax. FDG-PET/CT can identify sarcomatous change from benign neurogenic tumor with minimal misregistration, and can also detect metastatic disease. This case illustrates the importance of evaluating both metabolic and morphologic abnormalities to be able to formulate a proper treatment plan. This information can be obtained in a single session, using PET/CT.

The purposes of this study were to estimate the electrical conductivity of tissues by non-invasively measuring the electrical bio-impedance, to develop a new method for tissue diagnosis, i.e., electrical impedance tomography (EIT). Tissue models were first designed taking into consideration the distribution of the fat tissue, muscle and bone in the human forearm, and then the intra-tissue distributions of electrical potential and field, and the electrical impedance in the models was theoretically analyzed by the three-dimensional finite element method. The electrical impedance of both forearms was measured in healthy human subjects, and estimated the electrical conductivity of individual local tissues. The results of the analysis showed that the distributions of electrical potential and field were affected by the presence of fat tissue but not by the presence or absence of bone. In addition, as a result of calculation of the electrical resistance of the extracellular fluid (Re) in each model, it was found that the value of bio-impedance was influenced by the presence of fat tissue, and the value of bio-impedance was increased by the intervention of a fat layer. The electrical conductivity estimated by fitting the observed values to the values obtained by finite element analysis was 0.40 S/m and 0.15 S/m for male muscle and fat tissue, and 0.35 S/m and 0.11 S/m for female muscle and fat tissue, respectively. The sex difference in the slope of linear approximation in the estimation of electrical conductivity of the males and females was thought to be due to sex differences in the properties and structure of fat tissue. These results suggest that local tissues can be diagnosed differentially and electrically by percutaneous measurement of local bio-impedance and subsequent estimation of the electrical conductivity of each tissue.

The aim of this study was to examine the relationship between CT density (Hounsfield Unit, HU) and the degree of fluoro-deoxyglucose (FDG) uptake, demonstrated as standard uptake value (SUV). Twenty contiguous patients (9 males, 11 females, age range of 29-79) were performed FDG-PET/CT scan with 750ml of 5% iodine-based oral contrast agent. A region of interest (ROI) was placed manually on oral contrast in the lumen of stomach, small bowel and ascending colon, avoiding contamination of other structures, and the average SUV and average HU were determined. R square and p value were applied to evaluate the correlation. The correlation between SUV and HU in each separate location is not significant. When all regions are combined, p value is significant (

The aim of this article is to introduce the clinical utility of FDG PET as oncologic imaging. PET (positron emission tomography) is a newly developed imaging tool, and it has increased the accuracy of metabolic mapping of numerous malignancies, with significant impact on the management of cancer patients for initial staging, restaging and therapy monitoring. PET can provide functional information in addition to morphology from conventional imaging modalities. 18F-labeled 2-fluoro-2-deoxyglucose (FDG) is the most commonly used PET tracer and FDG PET can demonstrate the activity of glucose metabolism throughout the entire body in a single session. We describe the clinical utility of FDG in PET and display images of normal distribution and of patients with head and neck and lung cancer.

The purpose of this study was to examine the signal change occurring with different inversion times (TIs) of the flow-sensitive alternating inversion recovery (FAIR) technique and to compare with the perfusion image obtained with Gd-DTPA injection. The subjects were 11 patients with unilateral occlusive cerebrovascular disease. Two FAIR images with different TIs (800 ms and 1600 ms) were measured for each patient and dynamic perfusion MRI was performed to produce four kinds of parameter maps: mean transit time (MTT), time to peak (TTP), relative cerebral blood flow (rCBF) and relative cerebral blood volume (rCBV) maps. Asymmetry ratios (ARs) between the affected and contra-lateral vascular sides were measured in both FAIR images and the four dynamic parameter maps. The AR of the MTT map of the four parameters showed the highest correlation with that of the FAIR images, especially with that of TI = 1600 ms (r = 0.829), and the AR of the rCBV map revealed the worst correlation with the FAIR images. The AR of the FAIR image with TI = 800 ms was less correlated with that of MTT than that with TI = 1600 ms. These results suggested that the signal intensity of the FAIR image was influenced by flow transition time and the change in TI could be used to select the flow with a different transition time. Our study suggested that a longer TI in the FAIR technique might be more useful than a shorter TI for evaluating chronic occlusive cerebrovascular disease in the clinical setting.

Magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (proton MRS) findings before and after carnitine therapy in a patient with methylmalonic acidemia (MMA) are evaluated. The hyperintensity on T2-weighted image and diffusion-weighted image and the decreased apparent diffusion coefficient of bilateral basal ganglia were normalized in parallel with normalization of the elevated lactate levels and the decreased N-acetyl-aspartate levels, corresponding to improvement of clinical symptoms. MRI and proton MRS may serve as a suitable, noninvasive modality for monitoring treated MMA.

This is a report on a case of carbohydrate-deficient glycoprotein syndrome (CDGS) with neurological deficits. Magnetic resonance (MR) images showed remarkable atrophy of the cerebellum and brainstem, and hypointensity was seen in the pallidum on diffusion-weighted images (DWI), suggesting deposits of metal substances. In the cerebellum, proton MR spectroscopy (MRS) showed decreased concentrations of N-acetylaspartate and a complex of glutamine and glutamate (Glx) while the concentration of myo-inositol was increased, indicating neuronal impairment and gliosis. In the parietal lobe, there was an increased concentration of Glx, possibly reflecting dysfunction caused by liver injury. J. Magn. Reson. Imaging 2003;17:722–725. © 2003 Wiley-Liss, Inc.

Diffusion-weighted MRI (DWI) is used in the diagnosis of acute ischaemic disease of the brain, but it is not clear whether or not it can be used to differentiate an acute haematoma from an infarct. Our purpose was to identify any characteristic feature of acute haematomas which can be recognised on DWI and to evaluate the usefulness of DWI in acute cerebral stroke. We examined nine patients with acute haemorrhage using CT and MRI including DWI. We measured the volume and apparent diffusion coefficient (ADC) of the haematomas. All showed heterogeneous signal on DWI, and the centre of the large (>20 ml) haematomas especially a mixed pattern with high and low signal. The characteristic feature of acute haematomas was a peripheral low-signal region, found in all subjects regardless of the size of the haematoma; acute infarcts did not show this. This low-signal rim on DWI may be useful for differentiating an acute haematoma from an infarct.

We examined brain function and hemodynamic change using functional MRI (fMRI) and optical topography and compared those differences between normal volunteers and patients with Alzheimer's. As activating tasks, simple finger tapping and word chain games (shiritori in Japanese) were conducted by both normal volunteers and patients with Alzheimer's. The activated area of normal volunteers depicted by fMRI was shown in the primary motor area (finger tapping) and Broca's area (word chain game) and the hemodynamic change measured by optical topography were mainly prominent in those two areas even though the spatial resolution of optical topography was low. In patients with Alzheimer's, the activation by fMRI was spread to the bilateral hemisphere of the cerebrum, the hemodynamic change by optical topography was also larger than that of normal volunteers. We considered that the hemodynamic response would be changed in patients with Alzheimer's, and both fMRI and optical topography might be useful to evaluate the difference of brain function in clinical cases.

Autism appears to be characterized by a lack of “theory of mind.” The left medial frontal gyrus is the main area concerned with theoretical thought. We investigated the abnormalities in brain functions of autism by functional MRI by comparing a “theory of mind” story task with a “physical” story task. We compared the activation map of autism with normal controls. The results showed that the normal controls were dominant in activation in the left frontal lobe containing the left medial frontal gyrus. In autistic patients, diffuse activation was found in the bilateral frontal lobes and these patients tended to show more activation in the right side. These findings may reflect the impairment in the mentalizing process.

The apparent diffusion coefficients (ADCs) of water and brain metabolites were determined by proton MR spectroscopy on a clinical MR scanner for healthy volunteers and for pathological changes in cases of acute cerebral infarction and brain tumor. The ADCs of N-acetyl aspartate (NAA) and creatines in tissue involved in acute infarction were decreased compared to normal control values, while in tumors they showed increased values. Since NAA is a neuronal marker, these findings suggest that neuronal cell viscosity changes according to the pathological status of the tissue. The lactate ADC was significantly larger than the values for other major metabolites in cases of ischemia and tumor, suggesting that lactate is present in a different compartment. These results indicate that metabolite diffusion data can be used to reveal changes in the intracellular environment depending on the pathological status.

The situation of PACS installations in Japan from 1987 to 1999 has been investigated. By 1999, 751 PACS units have been installed. Of these, 613 are small-size PACS with less than four image display terminals, 96 are medium-size with 5–14 terminals and 42 are large-size with 15 up to 300 terminals. The 42 hospitals with large sized PACS have been retrospectively investigated from 1984 for PACS experiments and from 1989 for PACS operation. Most of these 42 hospitals have increased the number of PACS terminals by installing additional PACS units instead of reinforcing the existing single PACS. Some (23%) PACS installations have obviously not been successful because of low image transfer speed and inadequate image quality. The use of DICOMM interfaces has increased the number of modalities connected to PACS and influenced the spread of PACS installations in Japan. The status of HIS and RIS coupling to PACS and the use of PACS in primary diagnosis or in image referral are discussed. Assessment of PACS is now in a very early stage. Baseline studies of HIS/RIS/PACS effectiveness have been carried out to assess quantitatively the PACS merit. Radiologists’ answers to the questionnaire on PACS usage do not fully support the finding that the number of PACS installations is growing in Japan.

Huang, L., Ogushi, F., Tani, K., Ogawa, H., Kawano, T., Endo, T., Izumi, K., Ueno, J., Nishitani, H. and Sone, S. Thrombin Promotes Fibroblast Proliferation during the Early Stages of Experimental Radiation Pneumonitis. Radiat. Res. 156, 45-52 (2001). To clarify the role of thrombin in the pathogenesis of radiation-induced pneumonitis, we measured the thrombin activity and fibroblast growth-inducing activity in bronchoalveolar lavage fluid obtained from the irradiated lungs of rats at 1, 2, 4, 8 and 18 weeks after irradiation. Thrombin activity was not detected in the bronchoalveolar lavage fluid from unirradiated rats, but the bronchoalveolar lavage fluid from irradiated rats showed significantly increased thrombin activity which reached a maximum at 4 weeks after treatment. Higher fibroblast growth-inducing activity was detected in the bronchoalveolar lavage fluid from irradiated rats at 4 and 18 weeks than in fluid from unirradiated rats. Bronchoalveolar lavage fluid from irradiated rats that were pretreated with the thrombin inhibitors antithrombin III and argatroban showed significantly inhibited fibroblast growth-inducing activity and thrombin activity at 4 weeks. However, these thrombin inhibitors did not inhibit fibroblast growth-inducing activity in bronchoalveolar lavage fluid from irradiated rats at 18 weeks. Purified rat thrombin similarly induced proliferation of fibroblasts derived from irradiated and unirradiated rats. These findings suggest that thrombin may play an important role as a fibroblast growth-inducing factor during the early stages of radiation pneumonitis.

The hospital-wide PACS uses personal computer and general-purpose color CRT monitor as a client because many clients are demanded in the wards, but medical CRTs are too expensive; and the PACS stored and delivered endoscopic color images. Users should adjust each CRT monitor because of fewer administrators and too many clients. But the adjustment of color CRT monitors is not simple. It will be so complicated to meet the luminance characteristics, including maximum and minimum luminance and regional contrasts. We were afraid that the maladjustment of CRT caused misunderstanding in the daily practice. We should have an easy way of adjusting general-purpose CRT monitors from the recognition of CRT characteristics. In this paper, we focused on the adjustment of the contrast and brightness of color CRT monitors, and the users' behavior on this adjustment. The characteristic curves of luminance on several contrast and brightness settings were measured. The characteristic curve on the lower brightness and higher contrast seemed to be similar to the ideal curve of the medical CRT monitor. Users' settings were also similar to that according to clinical images.

Clear cell adenocarcinoma of the female urethra is a rare malignant tumor arising from urethral diverticulum or paraurethral ducts and glands, and extends to the submucosa surrounding the urethra. In the advanced stage, the tumor may involve adjacent organs such as the vagina, and may mimic gynecologic malignancy. We report 2 cases in which magnetic resonance imaging could reveal their urethral origin by detecting the normal urethra within the mass as targetlike appearance on axial T2-weighted image.

We evaluated neuronal impairment of adult moyamoya patients by proton magnetic resonance spectroscopy (MRS) and cerebral perfusion scintigraphy. After evaluating two methods for compensating relaxation times, we selected a long TR, short TE sequence to achieve better reproducibility. The cerebral blood flow (CBF) value was measured by scintigraphy following the method of quantification reported in the previous literature. N-acetyl aspartate (NAA) concentrations and CBFs value were decreased statistically (P < 0.05) compared with those of the age-matched normal controls. However, the decreased rate of NAA concentration was changed more than the CBF value, and no linear correlation was found between the two values. We considered that the NAA concentration was not always correlated with that of the present cerebral perfusion. The NAA concentration showed a more dispersive distribution in patients than in controls, indicating a large individual variation in neuronal impairment. We concluded that proton MRS may provide useful information about neuronal impairment in individual patients. J. Magn. Reson Imaging 1999;10:124–129. © 1999 Wiley-Liss, Inc.

Objective Decidual changes of endometrial tissue in endometriomas during pregnancy may manifest as mural nodules and mimic malignant transformation. We evaluated magnetic resonance findings of decidualized ovarian endometriomas for the differentiation from malignant transformation. Methods Magnetic resonance manifestations of 5 decidualized ovarian endometriomas were evaluated. High b-value diffusion-weighted images were performed in 3 cases. Results The mural nodules were demonstrated as linear, small nodular, broad-based nodular, or polypoid structures, which showed prominent hyperintensity on T2-weighted images and on diffusion-weighted images similar to normal endometrium or placenta. The apparent diffusion coefficient of decidualized mural nodules was significantly higher than that of malignant mural nodules of 7 ovarian cancers. Conclusions Endometrioma with prominent hyperintense mural nodules on T2-weighted images in a pregnant woman is highly suggestive for decidualized endometriomas. Diffusion-weighted images with the apparent diffusion coefficient measurement may help the diagnosis of this rare entity.

BACKGROUND: Breast conserving therapy is being established as a standard therapeutic procedure for early breast cancer in Japan. However, the indications of radiotherapy and a standardized therapeutic procedure have not been established yet. In this study, complications following radiotherapy were evaluated in patients who had previously undergone breast conserving therapy at Tokushima University Hospital. METHODS From October 1989 to March 1996, 60 women with stage I or II breast cancer underwent radiation therapy after breast conserving surgery, and all patients were followed-up for a median of 27 months. Radiation morbidity scoring of the breast and adjacent organs was performed using the toxity criteria of the Radiation Therapy Oncology Group (RTOG) and European Organization for Research andTreatment of Cancer (EORTC). RESULTS: Only 1 patient developed local recurrence, and no distant metastasisor death was observed. The cause of recurrence in 1 case was considered to be due to extended intraductal component. Although transient dermal reaction was induced by irradiation of the breast, no side effects that may cause cosmetic problems were found. No serious radiation complications were found in the lungs, ribs, heart or other adjacent organs. CONCLUSION: The adverse reactions caused by irradiation does not reduce the merit of combined use of radiation therapy in breast conserving therapy, and therefore, are not the hesitation factor in application of radiotherapy.

BACKGROUND To develop a new immunologic approach to multiple myeloma, the authors generated a monoclonal antibody against a human plasma cell specific antigen, HM1.24. Their previous study showed the antitumor effect of this antibody in severe combined immunodeficiency (SCID) mice bearing human myeloma xenografts. In the current study, the efficacy of anti-HM1.24 immunoglobulin (Ig) G and its F(ab')2 fragment were evaluated for radioimmunologic detection of the myeloma xenografts. METHODS SCID mice bearing subcutaneous RPMI 8226 tumors were injected with 125I-labeled antibodies, and radioactivity in the tumor and normal tissues was measured. Radioimmunoscintigraphy and autoradiography were performed to investigate the distribution of the antibodies. RESULTS In comparative biodistribution studies, the maximum tumor localization index of anti-HM1.24 F(ab')2 fragment was significantly higher than that of anti-HM1.24 IgG. Anti-HM1.24 F(ab')2 consistently had higher tumor-to-tissue ratio than anti-HM1.24 IgG and gave distinct tumor images by radioimmunoscintigraphy. Autoradiographic study showed that anti-HM1.24 F(ab')2 penetrated the tumor mass more uniformly than whole IgG antibody. CONCLUSIONS These results indicate that anti-HM1.24 antibody has the potential to provide a new approach to the immunodetection and immunotherapy of multiple myeloma and related plasma cell dyscrasias. Cancer 1998;82:2184-2190. © 1998 American Cancer Society.

In this paper, we present an approach for the segmentation of magnetic resonance images of the brain, based on Hopfield neural network. We formulate the segmentation problem as a minimization of an energy function constructed with two terms, the cost-term, that is a sum of errors' squares, and the second term is a temporary noise added to the cost-term as an excitation to the network to escape from certain local minima and be closer to the global minimum. Also, to ensure the convergence of the network and its utility in the clinic with useful results, the minimization is achieved in a way that after a prespecified period of time the energy function can reach a local minimum close to the global minimum and remain there ever after. We present here, segmentation results of two patients data diagnosed with a metastatic tumor and multiples sclerosis in the brain.

The purpose of this paper is to clarify whether copper accumulation in hepatocellular carcinoma (HCC) is a cause of high intensity signal pattern on T1-weighted images (T1-WI) by comparing the histologically proven copper accumulation with MR images. Forty-five surgically resected HCCs were analyzed. Distribution patterns of divalent copper by a modified Timm's method on their maximum cut surfaces were compared with signal patterns on corresponding T1-WI. The degree of copper accumulation in tumor compared with surrounding liver tissue was higher in 6 lesions, equal in 17 lesions, and lower in 22 lesions. High intensity pattern on T1-WI were observed in 3 of 6 lesions (50%), 10 of 17 lesions (59%), and 10 of 22 lesions (45%). Distribution patterns of copper were not correlated with intensity patterns on T1-WI. We conclude that the paramagnetic effect of divalent copper accumulation in HCC is insufficient to influence the MRI.

We experienced a case of pyruvate dehydrogenase deficiency observed by proton magnetic resonance spectroscopy( 1 H MRS). This case was diagnosed as West syndrome by characteristic convulsion and the periodic hypsarrhythmia pattern of EEG. At the age of 11 months, the first examination of 1 H MRS revealed a high peak of lactate, and the high concentration of lactate and pyruvate was confirmed in sampled cerebrospinal fluid (CSF). Deficiency of pyruvate dehydrogenase complex was finally diagnosed by genetic examination. Dichloroacetate was administered to the patient as therapy. Decrease of lactate in the brain was found by 1 H MRS. Lactate and pyruvate in the CSF was also decreased. In accordance with the suspension of dichloroacetate, increase of lactate in the brain was detected and the convulsions reappeared. After readministration of dichloroacetate, the patient was almost symptom free and lactate in the brain and CSF had decreased to the normal extent. We considered that 1 H MRS provides useful information for screening metabolic disorders of infants and assessing the efficacy of therapy.

We report a rare case of an urachal xanthogranuloma containing a urinary calculus, which was considered to have originated from vesicourachal diverticulum. The patient was a 66-year old woman with hematuria and pyuria. Computed tomography (CT) revealed a midline-situated supravesical cavitary mass containing a calculus. Sagittal images of magnetic resonance imaging (MRI) revealed continuity of the mass with the umbilicus. Fatty components of the xanthogranuloma showed low attenuation on CT and hyperintensity on T1-weighted images of MRI. The presence of a large calculus in the vesicourachal diverticulum may have caused continuous irritation resulting in the xanthogranulomatous formation.

Magnetic resonance imaging scans of the brain were obtained in 13 patients with myotonic dystrophy, seven with congenital myotonic dystrophy and six with adult-type myotonic dystrophy. All seven patients with congenital myotonic dystrophy had ventriculomegaly and a low IQ (DQ). Cerebral white matter lesions were observed in six cases, a small corpus callosum in four cases, a small brainstem in two cases, and a cerebellar white matter lesion in one case. Cerebral white matter lesions were observed in five of the six cases with adult-type myotonic dystrophy of which one had ventriculomegaly. The IQ (DQ) was significantly lower in patients with congenital myotonic dystrophy than in those with adult-type myotonic dystrophy. The incidence of a small corpus callosum or ventricular enlargement was higher in congenital myotonic dystrophy than in adult-type myotonic dystrophy. These findings may be related to the presence of neurologic impairment in congenital myotonic dystrophy.

We studied the feasibility of characterizing brain tumor tissue by localized proton magnetic resonance spectroscopy (1H-MRS). Twenty-six newly diagnosed tumors were examined by in-vivo 1H-MRS. The NAA (N-acetylaspartate)/Cho (choline) ratio of Grade 2 astrocytoma was higher than that of Grade 4. The Cho/Cr (creatine and phosphocreatine) ratio of meningioma was considerably higher than that of glioma of all grades. We have experienced only two cases of ependymoma and the Cho/Cr ratios of both were lower than that of glioma. It seems likely that 1H-MRS can be used to differentiate Grade 2 from Grade 4 in most cases of astrocytoma based on the NAA/Cho ratio, though a few cases will overlap. Meningioma can be distinguished easily from glioma, and the results of our study suggest that ependymoma shows a characteristic pattern on 1H-MRS, different from those of other brain tumors.

The brain of patients with adult type myotonic dystrophy was measured using MRI, and compared with age- and sex-matched controls. The width of the cerebrum, and the areas of the corpus callosum, pons and pituitary gland were significantly smaller in adult-type myotonic dystrophy than in the controls. The IQ of the patients with adult-type myotonic dystrophy was lower than that of controls. These results demonstrate a decreased volume of the brain and pituitary glands in myotonic dystrophy. These findings suggest a causal relationship for the mental retardation and endocrine dysfunction that may occur.

Ovarian cystadenofibroma is a benign tumor and may appear as a multilocular cystic mass with solid nodular components mimicking malignant ovarian tumor. Preoperative diagnosis is required to avoid excess surgical procedure. We report characteristic magnetic resonance imaging (MRI) findings of 2 cases with pathologic correlation. On T2-weighted images, the solid components of the tumors showed very low intensity, in which very high intense tiny cysts were present reflecting dense fibrous stromal proliferation with scattered small cystic glandular structures. This "black sponge"-like appearance was considered to be diagnostic.

Five patients with unilateral leg lymph edema had intraarterial injections of lymphocytes in the affected leg with consequent improvement in 3. To assess the degree of lymph edema, T2 and intensity ratio between the 2 legs in STIR images were used. Mean and SD of T2 values in the subcutaneous tissue were measured using a triple echo sequence and found larger on the edematous side than in the opposite extremity. The mean T2 shortening obtained after the lymphocyte therapy correlated well with the reduction of limb circumference. Mean T2 reflects the fluid content, and SD of T2 the fluid distribution in the subcutaneous tissue. The degree of lymph edema and the effect of therapy can be evaluated quantitatively by measuring the value of the T2 relaxation time.

We encountered a case of brain abscess that was difficult to differentiate from glioblastoma. Localized 1H-MRS was found to be useful for obtaining information on the biochemical status of brain abscess. The peak of lipid and high residual peak of NAA (N-acetyl-aspartate) were observed in the cystic lesion of the brain abscess by 1H-MRS. The NAA/Cho (Choline-containing compounds) ratio in brain parenchyma showing an edematous lesion before therapy gradually increased with the relief of inflammation.

This paper uses film dosimetry to investigate the relationship between multiple scan parameters of multidetector CT with automatic exposure control (AEC) and the surface dose distribution produced on a chest phantom.The characteristics of the film used in the film dosimeter were evaluated with regard to linearity, relative film response, and directional dependence. Measurements with an ionization chamber dosimeter and a water phantom were used to evaluate the accuracy of the film dosimeter measurements and to validate the dose profile measurements while changing the tube current, detector dimensions and pitch. When using AEC, the surface dose distribution on the chest phantom was analyzed while changing the detector dimensions and pitch.The linearity, relative film response, and directional dependence of the film were established. The measurement difference between the film dosimeter and ionization chamber dosimeter was within +/- 5% and the dose profile measurement results were validated. It was found that the surface dose distribution changed helically in the direction of the body axis depending on the scan parameters and the phantom.Using a film dosimeter, the relationship between various multidetector CT scan parameters and the surface dose distribution on a chest phantom was investigated and clarified.

1-Ethoxymethyl-5-fluorouracil (EM-FU) is a fluorinated pyrimidine derived from 5-FU, and 3-cyano-2,6-dihydroxypyridine (CNDP) is a chemical modulator which suppresses the catabolism of 5-FU by inhibiting dihydrouracil dehydrogenase in the liver. In this study, the metabolism of EM-FU and the suppression of 5-FU catabolism by CNDP were observed by in vivo 19F magnetic resonance spectroscopy in comparison with other similar drugs, because it is considered that the most effective mode of therapy using 5-FU is to suppress the catabolism of 5-FU in the liver and so to maintain for longer an effective blood level of 5-FU. The metabolism of EM-FU was very slow and the production of fluoro-beta-alanine was very low as compared to the case of tegafur. The catabolic suppression by CNDP was much stronger than that of uracil. Therefore co-administration of EM-FU and CNDP should suppress catabolism and maintain an effective blood level of 5-FU for a long period of time.

We studied the variations in the concentration of metabolites with brain region and age in autistic individuals and normal controls using multiple analysis of covariance. We examined 55 autistic individuals (2–21 years old, 47 male and eight female) and 51 normal children (3 months–15 years old, 26 boys and 25 girls). Single volumes of interest were placed in the frontal, parietal and temporal region on both sides, the brain stem and cingulate gyrus. The concentration of each metabolite was quantified by the water reference method. The concentration of N-acetylaspartate in the temporal regions (Brodmann's areas 41 and 42 ) in the autistic individuals were significantly lower than those in the controls (P < 0.05), but concentrations in other regions were not significantly different between the autistic individuals and controls. This suggests low density or dysfunction of neurones in Brodmann's areas 41 and 42 in autistic individual, which might be related to the disturbances of the sensory speech centre (Wernicke's area) in autism.

This study describes an improved method for examining and diagnosing temporomandibular joint (TMJ) dynamics by 3.0 T pseudodynamic MRI.Clinical observation and conventional static MRI of volunteers (one without and eight with TMJ arthrosis) were followed by 3.0 T pseudodynamic MRI in positions ranging from the mouth closed to mouth fully opened. Condylar head (Cd), articular disc anterior border (Da) and articular disc posterior border (Dp) were digitized on sagittal images to determine trajectory and velocity patterns.Patients were divided into three groups based on the presence or absence of dysfunction: Group 1, no dysfunction on the right or left side of the TMJ; Group 2, dysfunction on the right or left side of the TMJ; and Group 3, dysfunction on both the right and left sides of the TMJs. In 75% of patients (12 of 16 joints), pseudodynamic TMJ analysis was useful for determining a functional abnormality. Using a points system based on three trajectory and seven velocity patterns, discs with adhesion and perforation had significantly fewer points than discs with anterior displacement (with and without reduction) and discs with no abnormality (P = 0.0190.05).Trajectory and velocity patterns based on 3.0 T pseudodynamic MRI identified the affected side and determined the extent of morbidity in the Cd as well as the Da and Dp. The typical abnormal movement pattern of discs with anterior displacement (with and without reduction) and pathological structural changes of the articular disc (such as adhesion and perforation) could be identified.

Background Cardiac involvement is a recognised complication in female carriers of Duchenne muscular dystrophy (DMD). Since segmental or global left ventricle (LV) wall motion abnormalities in DMD carriers can arise even without apparent muscle weakness, it is difficult to differentiate cardiac involvement of a DMD carrier from other heart diseases in a non-invasive manner. Cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE) enables assessment of regional wall motion abnormality and myocardial damage with high spatial resolution. Objective To assess the utility of CMR for detection of myocardial damage in female carriers of DMD. Methods and results Gadolinium-enhanced CMR was performed in seven female DMD carriers. Physical examination, electrocardiography, chest radiograph, measurements of total creatinine kinase and brain natriuretic peptide levels, and two-dimensional echocardiography were also performed. Four (57%) of the seven carriers had LGE, and LGE was frequently observed at the subepicardial layer in the inferolateral segment. Two carriers had a focal LGE at the LV inferolateral wall without LV dilation or wall motion abnormalities. Conclusion CMR findings of DMD carriers were characterised by subepicardial LGE, which was localised at inferolateral segments. CMR may be a useful modality for detecting cardiac involvement in DMD carriers.

Objective We evaluated the feasibility of diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) measurement in differentiating benign and malignant ovarian tumors. Methods Surgically proven 49 ovarian tumors (39 malignant/borderline malignant and 10 benign) were examined. Results The solid portion of all 39 malignant tumors showed homogeneous or heterogeneous high intensity on DWI, whereas only 3 of the 10 benign tumors (3 thecomas) showed high intensity. The mean (SD) ADC value in the 39 malignant tumors (1.03 [0.19]) was significantly lower than that in 10 benign tumors (1.38 [0.30]). A relatively low ADC (1.08-1.20) in the 3 thecomas may reflect their abundant cellular nature, and the presence of low intensity on T2-weighted images was suggestive for benign fibrous tumor. Conclusions Low intensity on DWI with high ADC may suggest benign lesions; however, it may be occasionally difficult to differentiate benign and malignant lesions only on the basis of DWI.

The patients of osteoporosis comprised about 11 million people in Japan and it is one of the problems the aging society has. In order to prevent the osteoporosis, it is necessary to do early detection and treatment. The development of Multislice CT technology made it possible to perform the three dimensional (3-D) image analysis with higher body axis resolution and shorter scan time. The 3-D image analysis using multi-slice CT images of thoracic vertebra can be used as a support to diagnose osteoporosis and at the same time can be used for lung cancer screening which may lead to its early detection. We develop an automatic extraction algorithm of vertebra, and the analysis algorithm of the vertebral body using shape analysis and a bone density measurement for the computer aided diagnosis of osteoporosis.

Metabolism of tegafur in the rat liver was observed by in-vivo 19F magnetic resonance spectroscopy (MRS). After MRS observation, tegafur and q-fluorouracil (5-FU) in the liver were determined by a chromatographic method for comparison with the results of 19F-MRS. Rats were divided into 3 groups: 1) CCl4-induced liver injury group, 2) uracil combined group, 3) control group. Catabolism to fluoro-beta-alanine was suppressed in both the liver injury group and the uracil combined group. Low peaks of 5-FU and fluoronucleotides could be found only in the uracil combined group. The result of 19F MRS observation of each group was in agreement with the result of determination of tegafur and 5-FU by chromatography. This showed that substances which could be observed by 19F-MRS were in proportion to all intracellular fluoro-containing substances. 19F-MRS can provide direct information on the metabolism of fluoropyimidines non-invasively and it might be a useful aid in choosing suitable chemotherapy for patients.

Background: Uterine endometrial cancer is the most common gynecologic malignancy, and benign endometrial hyperplasia or polyps should be differentiated from endometrial cancer. In evaluating endometrial cancer on magnetic resonance imaging (MRI), the assessment of the depth of myometrial invasion is important because it closely correlates with the patient's prognosis. Purpose: To verify the feasibility of diffusion-weighted magnetic resonance imaging (DWI) to distinguish benign and malignant endometrial lesions, and to evaluate myometrial invasion of endometrial cancer. Material and Methods: Sixty-seven endometrial lesions including 45 cancers and 22 benign lesions (hyperplasia and polyps) were evaluated by DWI with apparent diffusion coefficient (ADC) measurement. The staging accuracies of DWI and gadolinium-enhanced T1-weighted images in the assessment of myometrial invasion were evaluated in 33 patients with endometrial cancer. Results: The ADC values (×10−3 mm2/s) in cancer and benign lesions were 0.84±0.19 and 1.58±0.36, respectively ( P Conclusion: DWI provides helpful information in evaluating benign and malignant endometrial lesions.

The purpose of this study was to determine which computed tomography (CT) attenuation parameter was the most appropriate to predict the presence or severity of anemia.The subjects of the study wer 500 patients who had undergone a peripheral blood examination within 24 h of an unenhanced CT scan. Regions of interest were placed in the left ventricular (LV) cavity, thoracic and abdominal aortic lumens, inferior vena cava, and interventricular septum. The CT attenuation difference between the LV cavity and interventricular septum was also calculated. The relation between these measurements and the blood hemoglobin level was analyzed. In addition, using several selected parameters, a receiver operating characteristic (ROC) analysis was also performed.The difference in CT attenuation between the LV cavity and interventricular septum revealed the greatest correlation. ROC analyses also revealed the greatest area under the ROC curve in the differences between CT attenuation.The best quantitative method for the diagnosis of anemia was the difference in CT attenuation between the left ventricle and interventricular septum.

This study aimed to compare with bone scintigraphy showed round focal accumulation and Multidetector Row CT (MDCT) findings.We obtained 101 patients (mean age 69.2 years; 75 men, 26 women) and 186 diseases. They were examined both MDCT and bone scintigraphy within a month of each other. We classified into two groups (with metastasis and spondylosis) according to their MDCT findings. Bone scintigraphy was estimated on planar image, MDCT was evaluated in three directions with 1 x 1 x 1 mm thickness.We determined 20 metastases cases and 81 of spondylosis. We could not judge abnormal findings on MDCT in 4 patients (1 metastasis, 3 spondylosis); thus, detectability by MDCT was 93.5%. In the spondylosis group, the accumulation lesions were localized on the lower vertebral body in 76 patients (59%), with most showing as osteophytes. In the metastasis group, 11 patients showed more than 1 accumulations, 9 were osteoblastic changes and 10 were lytic. There was a tendency that patients who accumulated more than 1 vertebral bodies (64%) had osteoblastic and irregular distribution and those who accumulated just one body (78%) were lytic and their locations were focused on the lateral side.For evaluating bone scintigraphy, MDCT finding was helpful to increase the detectability in bone metastasis. Therefore, we should refer to MDCT finding positively in reading bone scintigraphy.

The five year survival rate of the lung cancer is low with about twenty-five percent. In addition it is an obstinate lung cancer wherein three out of four people die within five years. Then, the early stage detection and treatment of the lung cancer are important. Recently, we can obtain CT and PET image at the same time because PET/CT device has been developed. PET/CT is possible for a highly accurate cancer diagnosis because it analyzes quantitative shape information from CT image and FDG distribution from PET image. However, neither benign-malignant classification nor staging intended for lung cancer have been established still enough by using PET/CT images. In this study, we detect lung nodules based on internal organs extracted from CT image, and we also develop algorithm which classifies benignmalignant and metastatic or non metastatic lung cancer using lung structure and FDG distribution(one and two hour after administering FDG). We apply the algorithm to 59 PET/CT images (malignant 43 cases [Ad:31, Sq:9, sm:3], benign 16 cases) and show the effectiveness of this algorithm.

Whole heart coronary MRA (WHCA) is a noninvasive method used to image all coronary arteries with cardiac and real-time respiratory gating. We compared the coronary depiction ability of 3T WHCA with that of 1.5T using healthy volunteers. In addition, we compared the study performance rate, which might differ at 3T and 1.5T due to the difference in specific absorption rate (SAR) limits. The coronary artery was classified into nine segments, based on the classification of the American Heart Association (AHA). Each observer was asked to evaluate WHCA with the three-point scale rating for each segment, and to measure the visible length of each coronary artery utilizing reconstructed CPR and VR images. Depiction at 3T was superior to that at 1.5T. The completion rate of study was 100% at 1.5T, but just 63% at 3T owing to SAR limits. Thus it was suggested that 3T WHCA might be feasible with the advantage of high depiction ability, if adequate SAR reduction techniques were developed.

An investigation was made of 5-fluorouracil metabolism in rat liver by 19F MRS. Fluoronucleotide synthesis increased markedly with liver injury and accelerated with uracil treatment, indicating that 19F MRS may serve as a new method for evaluating liver viability.