Preventive Effect of Rifampicin on Alzheimer Disease Needs at Least 450 mg Daily for 1 Year: An FDG-PET Follow-Up Study.

BACKGROUND: Rifampicin was reported to inhibit amyloid-ß oligomerization and tau hyperphosphorylation in mouse models and could serve as a promising available medicine for the prevention of Alzheimer disease (AD). To examine whether rifampicin has such preventive effects in humans, we retrospectively reviewed 18F-FDG-PET findings of elderly patients with mycobacterium infection treated with rifampicin. METHODS: Forty nondemented elderly patients treated with rifampicin for mycobacterium infections who showed AD-type hypometabolism were enrolled. The hypometabolic patterns were evaluated with stereotaxic statistical analysis and region of interest analysis. RESULTS: Before treatment, AD-type hypometa bolism was observed in 12 patients. The FDG uptake in the posterior cingulate cortex (PCC) was improved or stabilized in 6 patients after 12-month therapy (450 mg/day), whereas another 6 patients with 6-month therapy showed a decreased FDG uptake in the PCC. In patients who underwent FDG-PET only after treatment, the metabolic decline in the PCC was significantly milder in patients with ≥12 months of rifampicin treatment than in those with 6 months of treatment. Multiple regression analysis revealed that the dose of rifampicin and treatment duration significantly influenced FDG uptake in the PCC. CONCLUSION: The preventive effect of rifampicin depended on the dose and the treatment duration, and the effect needs at least 450 mg daily for 1 year.

Dehydrogenative desulfurization of thiourea derivatives to give carbodiimides, using hydrosilane and an iron complex.

Dehydrogenative desulfurization of thiourea derivatives (RNHC(S)NHR') has been achieved, to give carbodiimides (RN=C=NR'), in the reaction with hydrosilane and (η(5)-C5H5)Fe(CO)2Me. The obtained carbodiimide reacted with (η(5)-C5H5)Fe(CO)(SiR3) formed in the reaction to give an N-silylated η(2)-amidino iron complex, which was isolated and then characterized by X-ray analysis.

FDG PET imaging in a patient with primary seminoma of the prostate.

Primary seminoma of the prostate is extremely rare. We describe a case of a 35-year-old man who presented with difficulty in urinating. Physical findings were unremarkable, but a rectal examination revealed a slightly hardened prostate with a nodule in the right lobe. Blood parameters were normal; however, blood chemistry revealed slightly elevated lactic dehydrogenase, and microscopic hematuria was evident. Serum prostate acid phosphate, carcinoembryonic antigen, and alpha-fetoprotein values were within normal limits. Both computed tomography and magnetic resonance images revealed a large mass in the prostate gland. A prostatic sarcoma or malignant lymphoma was initially suspected. A systemic survey using 18-fluoro-2-deoxyglucose (F-18 FDG) positron emission tomography revealed focal FDG uptake in the prostate gland. A prostatic biopsy of the mass was histologically diagnosed to reveal an extragonadal seminoma.

FDG PET in Lhermitte-Duclos disease.

A 45-year-old man presented with a headache. The medical history included a partial thyroidectomy, a colon polypectomy, and stomach tumors (all benign adenomas) 34, 2, and 1 year earlier, respectively. CT showed a space-occupying lesion in the left cerebellar hemisphere with calcification. The mass showed a striated pattern of hyperintensity on T2-weighted images. An FDG-PET scan was performed after the intravenous administration of 250 MBq (6.8 mCi) F-18 FDG. The images of the brain showed a hypermetabolic area in the left cerebellar hemisphere. The whole body images showed no abnormal accumulation other than physiologic uptake. A presumptive diagnosis of Lhermitte-Duclos disease (LDD) was made.

Metastasis of the gastrointestinal tract: FDG-PET imaging.

We assess the usefulness of F-18-fluoro-deoxyglucose (FDG) positron emission tomography (PET) in the evaluation of gastrointestinal metastases. Four cases (five lesions) in which metastases from three lung cancers and one malignant fibrous histiocytoma (MFH) of the femur were found in the gastrointestinal tract were reviewed (men/women 3 : 1, age 63-78 years, mean 72 years). The five lesions were duodenal, jejunal metastasis, and two stomach metastases from lung carcinoma, and rectal metastasis from MFH of the femur. FDG-PET was unable to detect small masses, but it was able to detect unforeseen lesions such as gastrointestinal metastases because FDG-PET is a whole-body scan in a single-operation examination. FDG-PET imaging provided valuable information for the diagnosis of gastrointestinal metastasis.

Direct comparison study between FDG-PET and IMP-SPECT for diagnosing Alzheimer's disease using 3D-SSP analysis in the same patients.

PURPOSE: The purpose of this study was to evaluate and compare the diagnostic ability of 2-[(18)F]-fluoro-2-deoxy-D: -glucose (FDG) positron emission tomography (PET) and N-isopropyl-p-(123)I iodoamphetamine single photon emission computed tomography (IMP-SPECT) using three-dimensional stereotactic surface projections (3D-SSP) in patients with moderate Alzheimer's disease (AD). MATERIALS AND METHODS: FDG-PET and IMP-SPECT were performed within 3 months in 14 patients with probable moderate AD. Z-score maps of FDG-PET and IMP-SPECT images of a patient were obtained by comparison with data obtained from control subjects. Four expert physicians evaluated and graded the glucose hypometabolism and regional cerebral blood flow (rCBF), focusing in particular on the posterior cingulate gyri/precunei and parietotemporal regions, and determined the reliability for AD. Receiver operating characteristic (ROC) curves were applied to the results for clarification. To evaluate the correlation between two modalities, the regions of interest (ROIs) were set in the posterior cingulate gyri/precunei and parietotemporal region on 3D-SSP images, and mean Z-values were calculated. CONCLUSION: No significant difference was observed in the area under the ROC curve (AUC) between FDG-PET and IMP-SPECT images (FDG-PET 0.95, IMP-SPECT 0.94). However, a significant difference (P < 0.05) was observed in the AUC for the posterior cingulate gyri/precuneus (FDG-PET 0.94, IMP-SPECT 0.81). The sensitivity and specificity of each modality were 86%, and 97% for FDG-PET and 70% and 100% for IMP-SPECT. We could find no significant difference between FDG-PET and IMP-SPECT in terms of diagnosing moderate AD using 3D-SSP. There was a high correlation between the two modalities in the parietotemporal region (Spearman's r = 0.82, P < 0.001). The correlation in the posterior cingulate gyri/precunei region was lower than that in the parietotemporal region (Spearman's r = 0.63, P < 0.016).

Usefulness of FDG PET for diagnosis and radiotherapy of the patient with malignant lymphoma involving bone marrow.

We experienced a case of relapsed malignant lymphoma with multiple bone marrow or bone lesions. The case was diagnosed as follicular lymphoma by cytological biopsy of the right iliac bone, with (67)Ga scintigraphy showing abnormal, intense uptake in multiple bones. After about 10 months of systemic chemotherapy, a relapse was suspected because of pain in the bilateral legs and a high level of lactate dehydrogenase. Assessment of the lesions in the patient was difficult by computed tomography because the affected sites were localized mainly in the bone marrow. (18)F-Fluorodeoxyglucose (FDG) positron emission tomography (PET) was useful for detecting accurately the relapse sites in the bone marrow and enabled us to determine the field for radiotherapy. There are only a few reports of FDG-PET findings for such bone marrow malignant lymphomas. Therefore, we report the findings of FDG-PET for this case and review some of the literature about bone marrow lymphomas.

Usefulness of F-18 FDG-PET in detection of multiple endocrine tumors with duodenal carcinoid.

In a 76-year-old woman in whom hypercalcemia had been followed, whole body fluorodeoxyglucose positron emission tomography (FDG-PET) scan detected hypermetabolic areas in the left lower region of the thyroid gland, pancreas tail, and duodenum. CT, MR, biopsy, and surgery were performed and parathyroid adenoma, pancreatic gastrinoma, and duodenal carcinoid were diagnosed. Fluorine-18 (F-18) FDG-PET may be useful for diagnosis of multiple endocrine tumors with duodenal carcinoid.

Dialyzability of gadodiamide in hemodialysis patients.

PURPOSE: The aim of this study was to evaluate the contrast enhancement, pharmacokinetics, dialyzability, and safety of gadodiamide in patients on hemodialysis. MATERIALS AND METHODS: Thirteen hemodialysis patients with abdominal disease were examined after receiving intravenous gadodiamide (0.1 mmol/kg body weight) by magnetic resonance imaging (MRI) and were dialyzed at l, 3, 5, and 8 days. Blood samples were obtained immediately before, during, and at the end of the first hemodialysis session and immediately before and at the end of the next three sessions. The complete blood count, blood biochemistry, beta2-microglobulin, and gadolinium were measured. Dialysis of urea, creatinine, and gadolinium during the first hemodialysis session was assessed. Precontrast and postcontrast MRI and Gd-enhanced MR angiography (MRA) images were reviewed and visually evaluated by two radiologists; their evaluation was based on consensus. RESULTS: Gadodiamide did not cause any changes in renal function. An average of 73.8%, 92.4%, and 98.9% of the gadodiamide dose was eliminated by the end of the first, second, and third hemodialysis sessions, respectively. The average half-time of gadodiamide was 1.93 h (SD 0.55). The mean clearance of gadodiamide during hemodialysis was 63.5 ml/min (SD 21.9). There were no side effects related to the injection of gadodiamide. In all cases, diagnosable MRI and MRA images were obtained after gadodiamide injection in the hemodialysis patients. CONCLUSION: In hemodialysis patients, gadodiamide achieves diagnosable images. It is dialyzable and can be used safely without measures to increase excretion.

Uterine adenofibroma and endometrial stromal sarcoma associated with tamoxifen therapy: MR findings.

Tamoxifen therapy may result in a variety of endometrial proliferative lesions, including adenofibroma and endometrial stromal sarcoma (ESS). This report describes the MR findings of adenofibroma and ESS associated with tamoxifen therapy. When MRI demonstrates a uterine mass appearing as a heterogeneous mass in the endometrium or myometrium, adenofibroma and ECC must be considered as rare, but possible, diagnoses.

Intralobar pulmonary sequestration receiving arterial supply from the superior mesenteric artery: a case report.

We report a case of congenital anomaly of pulmonary sequestration by contrast-enhanced three-dimensional magnetic resonance (MR) angiography and digital subtraction angiography (DSA). The pulmonary sequestration receives a blood supply from the superior mesenteric artery. MR angiography technique has been employed in pulmonary sequestration.

An abnormal accumulation of fluorine-18-FDG PET in cytomegalovirus enteritis--a case report.

The source of a fever of unknown origin (FUO) and watery diarrhea in a 63-yr-old female with a history of disturbance of consciousness due to moyamoya disease was examined. Fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET), colonoscopy, blood analysis, and determination of cytomegalovirus (CMV) antigenemia were performed. FDG was found to be accumulated in the wall of a dilated colon, and extended from the transverse to sigmoid colon. Colonoscopy revealed edematous, inflammatory, and punched out lesions in accordance with the areas of abnormal FDG uptake. A biopsy specimen showed the antibody of CMV in the colonic mucosa, and CMV antigenemia was detected by an immunohistochemical assay using a monoclonal antibody for CMV pp65 antigen. From these findings, we strongly suspected CMV enteritis.

Findings of fluorine-18-FDG PET in extranodal origin lymphoma--in three cases of diffuse large B cell type lymphoma.

F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) is an excellent modality for non-invasive functional imaging of malignant lymphoma and is highly sensitive and specific for the detection of lymphoma lesions. Here, we report the findings of FDG-PET for three cases of diffuse large B cell type lymphoma (DLBCL) with extranodal tumors in the breast, stomach, and liver plus spleen, respectively. The whole body FDG-PET findings showed no evidence of lymph node (LN) involvement or distant metastasis. Strong FDG accumulations were observed in the only extranodal sites by whole body FDG-PET. Therefore, we could confirm that these cases were extranodal primary origins. Whole body PET is useful to determine the primary sites, that is, extranodal origin DLBCL with its clear images.

Gadolinium-enhanced dynamic MRI of breast hemangioma.

We describe a patient with hemangioma of the breast. The tumor showed an Ill-defined hypointense mass on T1-weighted imaging and hyperintense mass on T2-weighted imaging. After bolus gadolinium injection, the tumor showed heterogeneous enhancement in early phase and in the time-intensity an early intensive enhancement was followed by a plateau. This intensive enhancement in the early phase is not limited to breast carcinoma but can be found in breast hemangiomas as well.

[Three-dimensional analysis of left ventricular geometry using magnetic resonance imaging: feasibility and comparison with echocardiographic analysis].

OBJECTIVES: Reliability of left ventricular geometry assessed by echocardiography (Echo) using an assumed left ventricular mass (LVM) and one-dimensional eccentricity (relative wall thickness: RWT), remains questionable. This study evaluated the feasibility of three-dimensional left ventricular geometric analysis using magnetic resonance imaging (MRI). METHODS: Echocardiography and MRI were performed on 55 patients with hypertension. LVM was calculated using 0.8 (American Society of Echocardiography-cube LVM) + 0.6 g for Echo and the slice summation method for MRI. Eccentricity was determined by RWT (septal wall thickness + posterior wall thickness/left ventricular inner diameter) for Echo and LVM/1.05/left ventricular end-diastolic volume (LVEDV) ratio [MRI-mass volume/cavity (M/C) ratio] for MRI. Left ventricular geometry was classified into four patterns according to the presence/absence of left ventricular hypertrophy and abnormal/normal eccentricity (partition value: RWT = 0.44, MRI; M/C ratio = 2.0), and the patient distribution was compared between the two methods. RESULTS: Although the mean values for LVM were similar, the mean value for LVEDV by echocardiography was significantly higher (p < 0.0001) and the mean M/C ratio was significantly lower (r = 0.004) than those by MRI. There were widely dispersed LVM values at higher underlying values of LVM and significant correlations between MRI-LVEDV and MRI-LVM (r = 0.87) and between Echo-LVEDV and Echo-LVM (r = 0.75). There was a significant difference in patient distribution according to left ventricular geometric pattern between the two methods (p < 0.01). Concentric (n = 18) and eccentric hypertrophy (n = 12) were dominant patterns in Echo analysis, and concentric hypertrophy (n = 23) and concentric remodeling (n = 21) were dominant in MRI analysis. The left ventricular geometric patterns were different in 32 patients (58.0%). Inadequate LVEDV values in Echo were the primary cause of this phenomenon. CONCLUSIONS: Left ventricular geometric analysis by Echo results in inaccurate values. Three-dimensional left ventricular geometric analysis using MRI provides more accurate information about left ventricular geometry.