Biomedical subjects

Noriyuki Moriyama

Publications and source records attributed to Noriyuki Moriyama.

At least 19 recordsLinked to original sources

PubMed2006

Distant metastasis of prostate cancer: early detection of recurrent tumor with dual-phase carbon-11 choline positron emission tomography/computed tomography in two cases.

Several types of recurrence may be detected by radiologic assessment after treatment in patients with prostate cancer. However, early detection of distant metastasis using positron emission tomography has so far never been published. We report two patients who underwent hormone therapy or surgical resection for prostate cancer. They developed distant metastases which were detected on whole body [C-11] choline positron emission tomography/computed tomography with significant elevation of serum PSA level. In one patient, recurrent tumor of the supraclavicular node (6 mm) diminished in size after subsequent hormone therapy. Surgical resection of recurrent tumor of the lung (12 mm) was performed in the other patient, the pathology of which confirmed the metastatic adenocarcinoma derived from the prostate. The recurrent tumor can be correctly detected by dual-phase whole body [C-11] choline positron emission tomography/computed tomography.

Adenocarcinoma↗

PubMed2006

Comparison of observed and expected numbers of detected cancers in the research center for cancer prevention and screening program.

BACKGROUND: The Research Center for Cancer Prevention and Screening program is a one-arm prospective study designed to evaluate the effect of multiple modalities for cancer screening. Basic programs consist of screening tests for cancer of the lung, esophagus, stomach, colon, rectum, liver, gall bladder, pancreas and kidneys, in addition to prostate cancer screening for males and breast, cervical, endometrial and ovarian cancer screenings for females. OBJECTIVE: To investigate the possibility of overdiagnosis, we compared the observed numbers with expected numbers based on the model. METHODS: We calculated the expected number of cancers on the basis of negative or positive history of screening tests within the previous year, based on assumed sensitivity and sojourn time. Observed numbers of screen-detected cases for stomach, colorectal, lung, prostate and breast cancer were compared with expected numbers. RESULTS: From February 2004 to January 2005, 3786 participants were enrolled in our study. The overall cancer detection rate was 5.8% (119/2061) for males and 4.1% (71/1725) for females. No statistically significant difference was found between observed and expected cases for colorectal cancer screening, gastric cancer screening for females and lung cancer screening for males. Observed numbers of breast, prostate and lung cancer for females exceeded those expected (P < 0.05). CONCLUSIONS: Although cancer screening programs in the present study increased the detection of potentially curable cancers, these modalities, particularly lung, breast and prostate screening, might detect cancers which would not necessarily be clinically significant. We should therefore weigh up benefit and harm for such cancer screening programs.

Adult↗

PubMed2006

Disease activity and 18F-FDG uptake in organising pneumonia: semi-quantitative evaluation using computed tomography and positron emission tomography.

PURPOSE: The present study was conducted to evaluate whether( 18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) in combination with computed tomography (CT) reflects disease activity in patients with organising pneumonia. METHODS: Eighty-eight subjects who were normal (n=66) or who had proven organising pneumonia (n=22) underwent FDG-PET and CT imaging. The subjects included 55 men and 33 women, ranging in age from 24 to 63 years (mean 47 years). PET and CT data sets were digitally fused using a conformational PET/CT fusion algorithm. All scans were evaluated independently by two chest radiologists who were unaware of other clinical data. The visual score, maximal and mean standardised uptake value (SUV), and maximal and mean lesion-to-normal tissue ratio (LNR) were calculated. The imaging results were compared with the laboratory and pulmonary function test results. The inflammatory cells in the lesions were quantified immunohistochemically. RESULTS: The visual score, maximal and mean SUV, and maximal and mean LNR of the patients with organising pneumonia were significantly higher than those of the normal subjects. The patients with air-space consolidation had a significantly higher SUV than those without air-space consolidation (mean+/-SD 3.08+/-0.39 vs 2.35+/-0.56; p<0.05). The number of CD45(+) cells was positively correlated with the maximal SUV (r=0.632, p<0.01) and the maximal LNR (r=0.453, p<0.05). The number of CD8(+) T lymphocytes also showed positive correlations with the maximal SUV (r=0.540, p<0.01) and the maximal LNR (r=0.547, p<0.01). CONCLUSION: Patients with organising pneumonia have an enhanced FDG accumulation which reflects the degree of disease activity.

Adult↗

PubMed2006

Imaging liver metastases: review and update.

The radiologic diagnosis of liver metastasis involves detection, characterization, and tumor staging. Knowledge of the histopathologic changes that occur with metastases provides the best approach to the accurate interpretation of radiologic imaging findings, and in particular, radiologists need to choose appropriate imaging methods based on such knowledge. Because the majority of metastases are hypovascular, the merits of the routine acquisition of hepatic arterial dominant-phase images by contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI) are disputable. Hepatic arterial dominant-phase images may be obtained when hypervascular tumors are suspected or three-dimensional CT angiography is necessary. And, imaging during the portal venous phase is essential for detecting metastases, evaluating intrahepatic vessel invasion, and for assessing intratumoral necrosis or fibrosis. Equilibrium- to delayed-phase imaging 3-5 min after contrast administration may improve the detection of intratumoral fibrosis, and occasionally lead to more accurate tissue characterization. MRI offers diagnostic information on vascularity, amount of free water, hemorrhage, fibrosis, necrosis, and water molecule diffusion in metastases. And, liver-specific contrast agents like superparamagnetic iron oxide, liposoluble gadolinium chelate, and manganese may improve the MRI-based diagnosis of liver metastases.

Contrast Media↗

PubMed2006

Solitary capillary hemangioma of the lung: report of 2 resected cases detected by high-resolution CT.

We report 2 cases of capillary hemangioma, each presenting as a solitary nodule in the peripheral lung. Both of the patients were asymptomatic with a small solitary nodule that had revealed by computed tomography. In both cases, the nodule was resected surgically under a clinical diagnosis of early lung cancer. Macroscopically, each lesion was ill defined and irregular in shape with a dark brown cut surface. Microscopically, the alveolar septa in both nodules were thickened by accumulations of numerous thin-walled capillary vessels, which characteristically extended along, or infiltrated, each septum. We diagnosed these lesions as "solitary capillary hemangioma" of the peripheral lung. Tumors or tumorlike lesions of capillary vessels in the lung are rare. Among them, pulmonary capillary hemangiomatosis (PCH) has been described as multiple nodules in the lung parenchyma or bronchovascular walls, comprised of infiltrating thin-walled capillary blood vessels. Moreover, PCH-like foci have been found in a retrospective study of autopsy cases. However, the presented cases should be differentiated from PCH in terms of their clinical setting such as history of hypertension or veno-occlusive disease and multiplicity of the lesion. This is a rare case series of solitary capillary hemangioma discovered incidentally during life, and the lesions were difficult to differentiate radiologically from early lung cancer. After the recent advances in imaging diagnosis for early detection of peripheral lung cancer, these lesions are important to bear in mind for differential diagnosis of bronchioloalveolar carcinoma.

Diagnosis, Differential↗

PubMed2006

Staging performance of carbon-11 choline positron emission tomography/computed tomography in patients with bone and soft tissue sarcoma: comparison with conventional imaging.

The present study was conducted to compare the diagnostic accuracy between carbon-11 choline (11C-choline) positron emission tomography (PET)/computed tomography (CT) and conventional imaging for the staging of bone and soft tissue sarcomas. Sixteen patients who underwent 11C-choline PET/CT prior to treatment were evaluated retrospectively for staging accuracy. Conventional imaging methods consisted of 99,mTc-hydroxymethylene diphosphonate bone scintigraphy, chest CT and magnetic resonance imaging of the primary site. The images were reviewed and a consensus was reached by two board-certified radiologists who were unaware of any clinical or radiological information using hard-copy films and multimodality computer platform. Tumor stage was confirmed by histological examination and/or by an obvious progression in number and/or size of the lesions on follow-up examinations. Reviewers examining both 11C-choline PET/CT and conventional imaging classified T stage in all patients. Interpretation based on 11C-choline PET/CT, the Node (N) stage was correctly diagnosed in all patients, whereas the accuracy of conventional imaging in N stage was 63%. Tumor Node Metastasis (TNM) stage was assessed correctly with 11C-choline PET/CT in 15 of 16 patients (94%) and with conventional imaging in eight of 16 patients (50%). The overall TNM staging and N staging accuracy of 11C-choline PET/CT were significantly higher than that of conventional imaging (P < 0.05). 11C-choline PET/CT is more accurate than conventional imaging regarding clinical staging of patients with bone and soft tissue sarcomas. A whole body 11C-choline PET/CT might be acceptable for imaging studies of tumor staging prior to treatment.

Adolescent↗

PubMed2006

Multiple non-tumorous arterioportal shunts due to chronic liver disease mimicking hepatocellular carcinoma: outcomes and the associated elevation of alpha-fetoprotein.

PURPOSE: To elucidate the morphologic appearance of small non-tumorous arterioportal (AP) shunts mimicking hepatocellular carcinoma on helical computed tomography (CT), their associated outcomes, and their relationship with alpha-fetoprotein levels in patients with chronic liver disease. MATERIALS AND METHODS: Ten patients with multiple AP shunts on dynamic helical CT were evaluated. A non-tumorous AP shunt was defined as no increase or spontaneous regression in size on follow-up CT scans. The number and shape of shunts more than 5 mm in diameter were studied on a segment-by-segment basis on the initial CT scan, and compared with those on follow-up CT scans. Alpha-fetoprotein levels were measured at the same time as CT scanning was performed. RESULTS: Ten patients with 86 AP shunts (range 0.5-3.8 cm; mean 1.2 cm) underwent arterial, portal and delayed phase imaging of the entire liver. The AP shunts were geographic (44%), round (33%) or wedge-like (23%) in shape. All shunts changed from high- to iso-attenuation on the delayed phase CT. A follow-up CT (mean 73 days) revealed spontaneous disappearance in all but three (97%) of the 86 AP shunts. Furthermore, 16 new shunts appeared in different segments from the primary ones in four patients. The rapid elevation of alpha-fetoprotein levels to 5-10-fold higher than the baseline level was recognized at the same time as the initial appearance of AP shunts in three patients (30%). Further follow-up CT scans detected solitary hepatocellular carcinomas in four patients at a mean 1283 days after the initial CT. The location of the hepatocellular carcinomas was quite different from those of the initially recognized AP shunts. CONCLUSIONS: Non-tumorous AP shunts varied in CT appearance and demonstrated iso-attenuation in the delayed phase, most of which disappeared within 4 months. For these multiple small stains in chronic liver disease, periodic follow-up CT is recommended rather than alternative invasive interventions, even though there was an association with rapid elevation of alpha-fetoprotein levels.

Adult↗

PubMed2006

Diffuse large B-cell lymphoma presenting as a unilateral solitary round pulmonary hilar node infarction.

Unilateral solitary pulmonary hilar node adenopathy is a rare presentation of diffuse large B-cell lymphoma. In this report, the authors present a case with a solitary pulmonary hilar lymph node infarction caused by diffuse large B-cell lymphoma. Enhanced CT examinations revealed a well-defined round mass with homogenous low attenuation in the left pulmonary hilum. Both radiological imaging and pathological examination can provide useful information for the interpretation of abnormalities and may enable the diagnosis of rare aetiologies.

Biopsy↗

PubMed2006

Pancreas: optimal scan delay for contrast-enhanced multi-detector row CT.

PURPOSE: To prospectively determine optimal scan delays for multiphasic contrast medium-enhanced imaging of the pancreas with multi-detector row computed tomography (CT). MATERIALS AND METHODS: This study was approved by an institutional review committee, and patients gave written informed consent. One hundred ninety-one patients underwent three-phase CT of the pancreas after receiving intravenous contrast medium with a fixed duration injection of 30 seconds. Patients were prospectively assigned among four groups with scan delays of 25, 45, and 65 seconds (group 1); 30, 50, and 70 seconds (group 2); 35, 55, and 75 seconds (group 3); and 40, 60, and 80 seconds (group 4). Mean CT numbers of abdominal aorta, spleen, pancreatic parenchyma, superior mesenteric artery and vein, splenic vein, and hepatic parenchyma were measured, and increases in contrast enhancement on enhanced images were assessed. Qualitative analysis was performed with a four-point scale. RESULTS: Abdominal aorta and superior mesenteric artery enhanced at a mean of 35 seconds from the start of injection (both P < .001). Pancreatic parenchyma enhanced most intensely at 35-45 seconds (P < .001) with a peak enhancement at the mean of 40 seconds. Liver parenchyma enhanced most intensely at 55-65 seconds with a peak at 60 seconds (P < .001). The mean time to peak enhancement was 45 seconds for the splenic vein and 55 seconds for the superior mesenteric vein. Qualitative results were in good agreement with quantitative results (both P < .001). CONCLUSION: With the injection protocol used in this study, optimal scan delays for imaging the pancreas were 30-35 seconds for the abdominal aorta and the superior mesenteric artery, 35-45 seconds for the pancreas, 45 seconds for the splenic vein, and 55 seconds or later for the liver.

Adult↗

PubMed2006

MDCT of the liver and hypervascular hepatocellular carcinomas: optimizing scan delays for bolus-tracking techniques of hepatic arterial and portal venous phases.

OBJECTIVE: The purpose of our study was to determine the optimal scan delays required for hepatic arterial and portal venous phase imaging and for the detection of hypervascular hepatocellular carcinomas (HCCs) in contrast-enhanced MDCT of the liver using a bolus-tracking program. SUBJECTS AND METHODS: CT images (2.5-mm collimation, 5-mm thickness with no intersectional gap) detected an increase in the CT value of 50 H in the lower thoracic aorta. The images were obtained after an IV bolus injection of 2 mL/kg of nonionic iodine contrast material (300 mg I/mL) at 4 mL/s in 171 patients, who were prospectively randomized into three groups with scans commencing at 5, 20, and 45 seconds; 10, 25, and 50 seconds; and 15, 30, and 55 seconds for the first (acquisition time: 4.3 seconds), second (4.3 seconds), and third (9.1 seconds) phases, respectively, after a bolus-tracking program. CT values of the aorta, spleen, proximal portal veins, liver parenchyma, and hepatic veins were measured. Increases in CT values from unenhanced to contrast-enhanced CT were assessed using a contrast enhancement index (CEI). Spleen-to-liver and HCC-to-liver contrasts were also assessed. A qualitative degree of contrast enhancement in each organ was prospectively assessed by two independent radiologists. RESULTS: At 10-15 seconds, the CEI of the aorta reached 300-336 H and that of the spleen reached 97-108 H without significant enhancement of liver parenchyma (15-25 H). The CEI of the proximal portal veins moderately increased (75-104 H) at 10-15 seconds, but no significant enhancement of hepatic veins was observed (24-51 H). The CEI of liver parenchyma peaked (59-63 H) at 45-55 seconds, when the CEIs of the aorta (117-125 H) and spleen (73-82 H) decreased. Spleen-to-liver contrast (81-84 H) was highest at 10-20 seconds and HCC-to-liver contrast (39-44 H) was highest at 10-15 seconds. The qualitative results correlated well with quantitative results. CONCLUSION: The optimal scan delays for hepatic arterial and portal venous phases after the bolus-tracking program detected threshold enhancement by 50 H in the lower thoracic aorta for the detection of hypervascular HCCs were 10-15 and 45-55 seconds, respectively.

Aged↗

PubMed2006

Double hepatic arterial phase MRI of the liver with switching of reversed centric and centric K-space reordering.

OBJECTIVE: The purpose of our study was to evaluate the clinical feasibility and usefulness of a 2D spoiled gradient-recalled echo MR sequence with serial switching of reversed centric and centric k-space reordering for high-spatial-resolution gadolinium-enhanced double hepatic arterial phase (HAP) MRI of the liver. SUBJECTS AND METHODS: MR images (frequency, 512; phase encoding without interpolation, 224; 6-mm thickness with 1-mm gap; 30 slices per 18 seconds) were obtained with multiphase imaging in which central k-space line data were filled 10, 21, 49, and 181 seconds after arrival of contrast medium in the abdominal aorta for the early HAP (reversed centric reordering, center of k-space lines acquired at end of acquisition), late HAP (centric reordering, center of k-space lines at beginning of acquisition), portal venous phase (centric reordering), and equilibrium phase (centric reordering), respectively, in 102 consecutive patients with suspected liver disease, including 48 untreated hepatocellular carcinomas (HCCs) in 35 patients. Images were quantitatively assessed for degree of contrast enhancement in the abdominal aorta, spleen, portal trunk, liver parenchyma, hepatic veins, and HCCs. Images were qualitatively assessed for the effectiveness of contrast enhancement in each phase and for degree of image degradation due to artifacts. RESULTS: Enhancement of the abdominal aorta peaked in the early HAP, of the portal trunk in the late HAP, and of the hepatic parenchyma and veins in the portal venous phase. Mean HCC-to-liver contrast peaked in the early HAP and turned to a negative value in the portal venous and equilibrium phases. Sufficient image quality was achieved in 99 (97%) of the patients. One of the other three patients had motion artifacts due to body motion, and the other two had unsatisfactory respiratory suspension. Scan timing for early and late HAP was optimal in 74 (73%) of the patients, for late HAP lagged in 20 (20%), for early HAP was premature in six (6%), and for early HAP lagged in five (5%) of the patients. CONCLUSION: We confirmed the feasibility and usefulness of a 2D gadolinium-enhanced double HAP spoiled gradient-recalled echo sequence incorporating serial switching of reversed centric and centric k-space reordering. This method has the potential for use in high-spatial-resolution double HAP MRI for the diagnosis of hypervascular HCC.

Adult↗

PubMed2005

Extraskeletal osteosarcoma: extensive tumor thrombus on fused PET-CT images.

A 30-year-old woman developed extraskeletal osteosarcoma in the right buttock and thigh. Radiographs and unenhanced computed tomography (CT) showed a large, multilobulated mass accompanied by mineralized matrix. Contrast-enhanced CT and magnetic resonance (MR) images showed extensive tumor thrombus in the right internal- and external iliac veins. Co-registered positron emission tomography (PET) and CT images showed abnormal F-18 2-fluoro-2-deoxy-D-glucose (FDG) uptake in the tumor thrombus. PET study in our patient provided information concerning disease extent and viability of tumor thrombus.

Adult↗

PubMed2005

Solitary mediastinal lymph node metastasis of hepatocellular carcinoma: MR imaging findings.

A 65-year-old man with multiple hepatocellular carcinomas in the liver with type C viral hepatitis had a solitary mediastinal lymph node metastasis in the right paratracheal to tracheobronchial region. Surgical resection for the mediastinal metastasis was undertaken based on magnetic resonance (MR) imaging findings, suggesting its radicality. We assess the MR imaging findings and presumable pathways of lymphatic metastasis from the liver to mediastinal lymph nodes in this report.

Aged↗

PubMed2005

Does T2-weighted MR imaging improve preoperative detection of malignant hepatic tumors? Observer performance study in 49 surgically proven cases.

The purpose of our study was to determine whether or not the addition of T2-weighted fast spin-echo (SE) imaging to gadolinium-enhanced spoiled gradient-recalled-echo (GRE) imaging improves the observer performance in the preoperative detection of malignant hepatic tumors. Gadolinium-enhanced GRE and fat-suppressed T2-weighted fast SE images obtained in 49 patients with 82 surgically confirmed malignant hepatic tumors (40 hepatocellular carcinomas and 42 metastases) were retrospectively reviewed by three independent off-site observers. In the random review of images, gadolinium-enhanced GRE images were reviewed first; thereafter, T2-weighted fast SE images were added for combined review. Observer performance was evaluated with the McNemar's test and receiver operating characteristic curve analysis. For gadolinium-enhanced GRE images alone vs. combined images, sensitivities for detection were 78% vs. 79% for hepatocellular carcinomas (P>.05), 67% vs. 71% for metastases (P<.05) and 72% vs. 75% for tumors overall (P<.05), respectively. The Az values were 0.892 vs. 0.889 in hepatocellular carcinomas (P>.05), 0.797 vs. 0.828 in metastases (P<.05) and 0.839 vs. 0.846 in tumors overall (P>.05), respectively. Our results showed that the addition of T2-weighted fast SE imaging to gadolinium-enhanced GRE imaging improved the observer performance in the detection of metastases.

Adult↗

PubMed2005

Thin-section MRI with a phased-array coil for preoperative evaluation of pelvic anatomy and tumor extent in patients with rectal cancer.

OBJECTIVE: The aim of our study was to assess the accuracy of thin-section MRI performed with a phased-array coil as a technique for the preoperative evaluation of pelvic anatomy and tumor extent in patients with rectal cancer. CONCLUSION: Thin-section MRI with a phased-array coil is accurate and reliable for preoperative evaluation of pelvic anatomy and depth of transmural tumor invasion. Thus, it may be helpful in the selection of the appropriate treatment for patients with rectal cancer.

Adult↗

PubMed2005

Expression of vascular endothelial growth factor in hepatocellular carcinoma and the surrounding liver and correlation with MRI findings.

OBJECTIVE: The purpose of our study was to assess the correlation between the quantitative and qualitative imaging findings on unenhanced and gadolinium-enhanced MR images and the intensity of vascular endothelial growth factor (VEGF) expression in hepatocellular carcinomas and in the surrounding nontumorous liver. MATERIALS AND METHODS: The intensities of VEGF expression in hepatocellular carcinoma and in the surrounding liver by Western blot analysis were converted to VEGF expression indexes (VEGF(IND)) in 22 surgical specimens ranging in size from 14 to 126 mm (mean, 47.6 +/- 29.5 mm) that were resected in 22 patients (17 men and five women; age range, 41-85 years [mean, 64 years]) between April 2000 and October 2002. MR images were retrospectively evaluated to determine contrast-to-noise ratios (CNRs), signal intensity SD ratios, and phase-shift indexes. Signal intensity characteristics of hepatocellular carcinomas were reviewed independently by two experienced radiologists who were unaware of the pathologic diagnosis or the results of immunoblotting. CNRs, SD ratios, and phase-shift indexes were correlated with VEGF(IND) using a simple regression test, and signal intensity characteristics were correlated with VEGF(IND) using the Spearman's rank correlation test. RESULTS: On opposed-phase T1-weighted spoiled gradient-recalled echo (GRE) images, CNRs correlated inversely with the VEGF(IND) of hepatocellular carcinomas (r = -0.46, p = 0.038). CNRs on T2-weighted fast spin-echo images correlated directly with the VEGF(IND) of hepatocellular carcinomas (r = 0.49, p = 0.025), and on gadolinium-enhanced hepatic arterial phase GRE images marginally and inversely correlated with VEGF(IND) (r = -0.39, p = 0.081). On T2-weighted fast spin-echo images, SD ratios correlated directly with the VEGF(IND) of hepatocellular carcinomas (r = 0.44, p = 0.044). No correlation was found between phase-shift indexes and VEGF expression. The qualitatively assessed signal intensity heterogeneities of hepatocellular carcinomas correlated directly with the VEGF(IND) of hepatocellular carcinomas on opposed-phase T1-weighted GRE, T2-weighted fast spin-echo, hepatic arterial phase GRE, and equilibrium phase GRE images. CONCLUSION: Our results indicate that the signal intensity and heterogeneity of hepatocellular carcinomas on MR images correlate with the degree of VEGF expression in hepatocellular carcinomas.

Adult↗

PubMed2005

Vascular virtual endoluminal visualization of invasive colorectal cancer on MDCT colonography.

OBJECTIVE: The purpose of this study was to assess the utility of vascular views for visualization of invasive colorectal cancers on contrast-enhanced MDCT colonography. CONCLUSION: By means of Hounsfield-transparency settings, we obtained virtual endoluminal images that show vascular structures and delineate invasive cancers of the colorectal wall, and we call these images "vascular views." Using this technique for contrast-enhanced MDCT colonography, we found that the increase in flow and pooling of blood related to angiogenesis of cancerous lesions is easy to identify and that this finding is useful in the detection of invasive colorectal cancers.

Adult↗

PubMed2005

Myxoinflammatory Fibroblastic Sarcoma: MR Appearance and Pathologic Correlation.

OBJECTIVE: The purpose of our study was to define the MR appearance of myxoinflammatory fibroblastic sarcoma of the soft tissues and to make correlations with the histopathologic features. CONCLUSION: Myxoinflammatory fibroblastic sarcoma is an uncommon malignancy that typically affects adult subjects, who present with painless swelling. This lesion manifests on MR images as a poorly circumscribed mass involving the underlying tendon sheath in the distal extremities.

Adult↗