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PURPOSE: Positron emission tomography (PET) and the maximum standardized uptake value (SUVmax) is a useful technique for assessing malignant tumors. Measurements of SUVmax in multiple lesions per patient frequently require many time-consuming procedures. To address this issue, we designed a novel interface named SUV Navigator (SUVnavi), and the purpose of this study was to investigate its utility. MATERIALS AND METHODS: We measured SUVmax in 661 lesions from 100 patients with malignant tumors. Diagnoses and SUVmax measurements were made with SUVnavi, 2D, and 3D measurements. SUV measurement accuracy in each method were also evaluated. RESULTS: The average reduction in time with SUVnavi versus 2D was 53.8% and 3D was 37.5%; time required with SUVnavi was significantly shorter than with 2D and 3D (P < 0.001 and P < 0.001, respectively). The time reduction and lesion number had a positive correlation (P < 0.001 and P < 0.001, respectively). SUVmax agreed with precise SUVmax in all lesions measured with SUVnavi and 3D but in only 466 of 661 lesions (70.5%) measured with 2D. CONCLUSION: SUVnavi may be useful for rapid [18F]-fluorodeoxyglucose positron emission tomography/computed tomography ([18F]-FDG PET/CT) image interpretation without reducing the accuracy of SUVmax measurement.

Positron emission tomography (PET) and the maximum standardized uptake value (SUVWe measured SUVThe average reduction in time with SUVnavi versus 2D was 53.8% and 3D was 37.5%; time required with SUVnavi was significantly shorter than with 2D and 3D (P 0.001 and P 0.001, respectively). The time reduction and lesion number had a positive correlation (P 0.001 and P 0.001, respectively). SUVSUVnavi may be useful for rapid [

Author, PURPOSE: The purpose of the present study is to evaluate the clinical value of dual-time-point F-18 FDG PET/CT imaging to differentiate malignant lymphoma (ML) from benign lymph node (BLN). MATERIALS AND METHODS: The subjects were 310 lymph nodes in 84 patients (195 ML lesions in 30 patients and 115 BLN in 54 patients associated with various etiologies.). F-18 FDG PET/CT scan was performed at 50 minutes (early scan) and at 100 minutes (delayed scan) after the injection. First, the maximum standardized uptake value (SUVmax) of each lesion at early and delayed scan was calculated. Second, we estimated the difference between early and delayed SUVmax (D-SUVmax) and the retention index (RI-SUVmax) to evaluate the change of tracers in the lesions. Furthermore, proper cut-off values of them were evaluated using by receiver operating characteristic analysis. The efficacy of each parameter was analyzed with ANOVA. RESULTS: Delayed SUVmax and D-SUVmax in ML were significantly higher than those in BLN. Proper cut-off value in delayed SUVmax was 4.0 and in D-SUVmax was 1.0. When the proper cut-off value in D-SUVmax was applied, the D-SUVmax yielded the role of diagnosis with sensitivity of 82.6%, specificity of 65.2%, positive predictive value of 80.1% and negative predictive value of 68.8%, respectively. CONCLUSIONS: The delayed SUVmax and D-SUVmax were useful indices to differentiate ML from BLN, regardless of histologic subtype. Dual-time-point F-18 FDG PET/CT imaging may help to consider whether there is any need to proceed to more invasive tests, such as biopsy, in individual patients.

Author, An F-FDG-PET with CT scan was performed to stage a tongue cancer, revealing the hypermetabolic region in the thoracic vertebra. This corresponded to a benign lesion seen on MRIs and CT.Although these findings suggested a vertebral hemangioma, "hot" vertebra in FDG-PET was atypical. The final diagnosis was confirmed capillary hemangioma by the scopic biopsy and this lesion was no change at 1 year later.Careful interpretation of metabolic (FDG-PET) and anatomic (CT and MRI) images should be performed to accurately characterize the foci of increased FDG uptake.

BACKGROUND AND PURPOSE: Although radiation induced damage to the salivary gland is a known complication of radioactive iodine ((131)I) therapy for thyroid carcinoma, prediction of the severity and reversibility of sialoadenitis is difficult. Our aim was to correlate the extent of salivary dysfunction assessed by salivary gland scintigraphy with changes in the volume and attenuation of salivary glands on nonenhanced CT in postoperative patients with thyroid cancer treated with RIT. MATERIALS AND METHODS: Forty patients with thyroid carcinoma, 13 men (age range, 21–80 years) and 27 women (age range, 28–75 years) who underwent a total thyroidectomy and were treated with RIT were assessed retrospectively. On CT, the percentage of volume reduction and the difference in attenuation of the parotid and submandibular glands after RIT were determined and correlated with the extent of radiation-induced salivary dysfunction on scintigraphy. RESULTS: The salivary gland volume significantly decreased with an increase in the dysfunction grade on scintigraphy for both the parotid and submandibular glands (P < .001). The attenuation significantly increased with an increase in the dysfunction grade on scintigraphy for the parotid gland (P < .001), but not for the submandibular gland. The cutoff value of volume reduction to diagnose severe gland dysfunction was 19.5% (sensitivity, 86.0%; specificity, 100%) for the parotid gland and 31.0% (sensitivity, 100%; specificity, 97.0%) for the submandibular gland, and that of the attenuation change was 9.8 HU (sensitivity, 81.0%; specificity, 95%) for the parotid gland. CONCLUSIONS: The reduction in volume of the parotid and submandibular glands and the increase in attenuation of the parotid gland on nonenhanced CT can be indicators of the grade of RIT-induced salivary dysfunction.

Background In the primary infection of pulmonary histoplasmosis, pulmonary lesions are commonly solitary and associated with hilar and/or mediastinal nodal diseases, which spontaneously resolve, resulting in calcifications in individuals with normal cellular immunity. Purpose To assess the lymphatic drainage to the mediastinum from each pulmonary segment and lobe using computed tomographic (CT) observations of a calcified primary complex pulmonary histoplasmosis and predict which patients with N2 disease that would benefit from surgery. Material and Methods We collected 585 CT studies of patients with primary complex histoplasmosis consisting of solitary calcified pulmonary lesions and calcified hilar and/or mediastinal nodal disease. Using the N stage criteria of non-small cell lung cancer, we assessed the distribution of the involved hilar and mediastinal nodes depending on the pulmonary segment of the lesion, with a focus on skip involvement. We also assessed the correlation between the incidence of N1and skip N2 involvement and the mean number of involved mediastinal nodal stations in the non-skip N2 and skip N2 groups. Results Skip involvement was common in the apical segment (9/45, 20.0%), posterior segment (7/31, 22.6%), and mediolbasal segment (13/20, 65.0%) in the right lung, and in the apicoposterior segment (7/55, 12.7%), lateral basal segment (6/26, 23.1%), and posterobasal segment (16/47, 34.0%) in the left lung. The incidence of skip involvement in each segment showed a significant inverse correlation with that of N1 involvement (r = –0.51, P Conclusion Our data showed a predictable pattern of segmental and lobar lymphatic drainage to the mediastinum and suggested that skip involvement could represent the initial mediastinal node involvement via direct lymphatic drainage.

Background There is an improved prognosis for T4 non-small-cell lung cancer in patients who show particular patterns of direct mediastinal invasion. The particular patterns suggest the presence of direct pathways other than the pulmonary hilum between each of the lungs and the mediastinum/chest wall. Purpose To determine the incidence and number of such direct pathways in pneumothorax patients as well as the factors that affect the development of these pathways. Material and Methods Two radiologists independently analyzed multidetector computed tomographic images of 81 patients with pneumothorax to assess the incidence and distribution pattern of the cross-bridging structures in the pleural cavity. Results Cross-bridging structures were observed in the right pneumothorax in 34/54 (63%) patients and in the left pneumothorax in 19/32 (59%) patients. The number of cross-bridging structures was found to be positively correlated with ageing and pulmonary disease. The distribution patterns of cross-bridging structures were found to be specific in formation and often in repeated locations, regardless of the presence of pulmonary disease or the age of the patient. Conclusion Cross-bridging structures in pneumothoraces were found more frequently in older patients and in patients with pulmonary disease. However, some of the cross-bridging structures may have been congenital because of their specific formations and repeated locations.

STUDY DESIGN Case report. OBJECTIVE To describe a case of solitary metastasis of the seventh thoracic vertebra (T7) from lung cancer 15 years after surgery. SUMMARY OF BACKGROUND DATA Late recurrence of the bone over 5 years after curative surgery for lung cancer is highly exceptional. In addition, bone metastasis from lung cancer showing a coarse trabecular pattern of the vertebra on computed tomography (CT) is quite unusual. METHODS A case of solitary metastasis of T7 from lung cancer 15 years after surgery showing a pseudohemangioma appearance of the vertebra on CT is presented. RESULTS A 66-year-old man presented with a 2-month history of gradually progressed numbness and muscle weakness of the bilateral leg, with a more recently developed spastic gate. He had undergone a left lower lobectomy for lung cancer 15 years previously. Magnetic resonance imaging showed an ill-defined mass lesion involving the entire vertebral body of T7 with extension into the posterior element and surrounding soft tissue, which resulted in moderate spinal canal stenosis. CT showed a coarse trabecular pattern at T7 with a mild compression fracture. No other lesion was detected by whole-body CT and bone scintigraphy. Tumor resection and T5-T9 posterior spinal fusion had been performed, and a pathologic diagnosis of metastatic pulmonary adenocarcinoma of the bone was established. Additional radiation therapy (40 Gy) was added, and the patient recovered and continued to survive uneventfully at the 3-month follow-up. CONCLUSION We have reported a rare case of solitary metastasis to T7 appearing 15 years after surgery for lung cancer. The incidence of lung cancer recurrence more than 5 years after surgery is exceedingly low; however, even in patients with lung cancer, late occurrence of bone metastasis should be considered and included in the differential diagnosis of a pseudohemangioma appearance of the vertebra.

Pancreatic carcinoma is a malignant tumor with poor prognosis and its early detection is still a clinical problem. The aim of this study was to evaluate the efficacy of carbon-11-labeled acetate (11C-acetate)-positron emission tomography (PET) for the detection of pancreatic carcinoma in a BxPC-3 human pancreatic carcinoma xenograft-bearing immunodeficiency BALB/c-nu nude mice model.Whole-body 11C-acetate and fluorine-18-labeled fluorodeoxyglucose (F-FDG) micro-PET imaging were performed weekly on BxPC-3 human pancreatic carcinoma xenograft-bearing BALB/c-nu nude mice from the 2nd week after tumor cell inoculation. Regions of interest method and tumor-to-nontumor ratio (T/N ratio) were used for semiquantitative evaluation. Tumor proliferation was evaluated by immunohistochemistry analysis of proliferating cell nuclear antigen.Radiotracer accumulation in the tumor xenografts could be detected 1 week earlier in 11C-acetate-PET than that in 18F-FDG-PET. Peak T/N ratio was obtained at the 5th week in 11C-acetate-PET and at the 4th week in 18F-FDG-PET. T/N ratio in 11C-acetate-PET was lower than that in 18F-FDG-PET during the same period. By visual evaluation, tumor xenografts were more easily observed in 11C-acetate-PET than in 18F-FDG-PET in most of the mice. Linear correlation analysis indicated T/N ratios in C-acetate-PET had no significant correlation with those in 18F-FDG-PET. Tumor size, T/N ratio in 11C-acetate-PET, and T/N ratio in 18F-FDG-PET were not found to be significantly correlated with tumor proliferating cell nuclear antigen expression.11C-acetate-PET imaging can be used for the detection of pancreatic carcinoma. In the early stage of tumor growth, 11C-acetate-PET has better detectability than that of 18F-FDG-PET.

author, Objective: To identify the brain areas which control the bladder storage by Tc-99m HMPAO SPECT with Neurological Statistical Image Analysis Software (NEUROSTAT) in patients with detrusor overactivity (DO). Methods: SPECT scans were performed on nineteen patients with DO. And eight patients with normal detrusor function, who has some storage symptoms of lower urinary tract as the patients with DO, also had SPECT scan, as control. All the subjects were male and right-handed, and were scanned twice under two conditions: resting state and urine withholding state. NEUROSTAT was adopted to analyze the difference in brain blood perfusion between groups and states. The results were displayed on Z-score images at a significance threshold of P < 0.05 with correction for multiple comparisons. Results: No region reached significant threshold in comparison of patients with DO and normal detrusor function in resting state. There were significant increases in tracer activity in the right inferior frontal gyrus and the right middle temporal gyrus during urine withholding state as compared with resting state in patients with normal detrusor function. Among the regions, the right inferior frontal gyrus was distinctly prominent at both Z-score and the extent. The regions that were activated significantly in patients with normal detrusor function, did not reach significant threshold during urine withholding in patients with DO. Conclusions: The study indicated that the right inferior frontal gyrus and the right middle temporal gyrus, especially the right inferior frontal gyrus, played a role in cerebral control of bladder storage, inhibiting the contraction of detrusor in urine storage.

OBJECTIVE. The great potential of MRI for assessing gastrointestinal abnormalities in fetuses has been described. T1-weighted images may add additional information to T2-weighted images in diagnosing fetal gastrointestinal abnormalities. The objective of this study was to assess the performance of a 3D volumetric interpolated breath-hold sequence (VIBE) in evaluating the normal and abnormal fetal gastrointestinal tract.CONCLUSION. VIBE provides high-quality T1-weighted and 3D MR colonography images for the evaluation of the normal and abnormal gastrointestinal tract in fetuses, and 3D MR colonography provides excellent delineation of the meconium.

The purpose of this study was to investigate the myocardial fatty acid metabolism in patients with hypertrophic cardiomyopathy (HCM) from dynamic SPECT through a compartment model analysis.Twenty-four normal controls, seven patients with left ventricular hypertrophy (LVH) due to essential hypertension (eHT), and 30 patients with HCM were studied. 123I-BMIPP and 99mTc-tetrofosmin SPECT were performed. All the myocardium was divided into 13 segments, and a total of 390 segments of HCM were categorized into early, moderately and severely advanced HCM segments, based on these SPECT imaging. By using the myocardial and blood pool time-activity curves, BMIPP pharmacokinetics were analysed through a two-compartment model. We defined k1 and k2 as influx and outflux rate constants between blood and myocardial reversible component, and k3 as the specific uptake rate constant between myocardial reversible and irreversible compartments.The averages of k3 in HCM were higher than in normal. In contrast, the averages of k1/k2 in HCM were lower than in normal, and gradually decreased with progression of HCM. There are no significant differences in these indexes between normal controls and patients with LVH due to eHT.k3 might be a sensitive predictor for early detection of HCM, and k1/k2 could be a useful index to evaluate its progression. A mathematical compartment model analysis with a BMIPP SPECT study might be useful not only for identification of HCM in very early stage, but also for evaluation of the progression of HCM.

Purpose: To prospectively evaluate chemical shift magnetic resonance (MR) imaging for differentiating thymic hyperplasia from tumors of the thymus gland. Materials and Methods: The institutional review board approved this study; informed consent was obtained and patient confidentiality was protected. The authors assessed 41 patients (17 male, 24 female; age range, 16–78 years) in whom thymic lesions were seen at chest computed tomography. Patients were assigned to a hyperplasia group (n = 23) (18 patients with hyperplastic thymus associated with Graves disease and five with rebound thymic hyperplasia) and a tumor group (n = 18) (seven patients with thymomas, four with invasive thymomas, five with thymic cancers, and two with malignant lymphomas). T2-weighted fast spin-echo and T1-weighted in-phase and opposed-phase MR images were obtained in all patients and visually assessed. A chemical shift ratio (CSR), determined by comparing the signal intensity of the thymus gland with that of the paraspinal muscle,...

Kawasaki disease (KD) is a leading cause of CAD in children. The impairment of cardiac sympathetic nerve function (CSNF) in the adult patients with coronary artery disease (CAD) could often be seen. However, little is known concerning the impairment of CSNF in KD patients. We investigated CSNF and its relationship with myocardial perfusion in KD patients. Eleven children with KD and 4 controls were studied with 123I-metaiodobenzylguanidine (MIBG) and stressed 201Tl single photon emission computed tomography. By the findings on coronary artery angiography (CAG), the patients were divided into 2 groups: A, without stenosis; B, with significant stenosis and/or old myocardial infarction. CSNF was evaluated from the uptake of 123I-MIBG. While myocardial perfusion was evaluated from 201Tl uptake. The numbers of patients in the groups A and B were 7 and 4. Perfusion defect was found in 0, and 2 patients in group A (0%), and B (50%). 123I-MIBG defects were found in 1 and 4 patients in the group A (14%) and B (100%). There were excellent concordances between the finding of 201Tl and 123I-MIBG in group A. While in group B, the coronary territories with 123I-MIBG defects were significantly more than those with perfusion defects (p < 0.05). In KD patients, the impairment of CSNF might be subsequent to coronary artery stenosis and was more severe than the injury of myocardial perfusion.

A 76-year-old woman with acute myocardial infarction underwent percutaneous coronary angioplasty followed by treatment with an angiotensin-converting enzyme (ACE) inhibitor, lisinopril. Her renal function deteriorated after the administration of lisinopril, so it was changed to another ACE inhibitor, temocapril. Renography suggested a complication of severe right renal artery stenosis, and renal angiography revealed bilateral renal artery stenoses. Her renal hemodynamics were assessed by 99mTc-Mercaptoacetyltriglycine (99mTc-MAG3)-renography before and after withdrawal of temocapril. The authors concluded the patient had essential hypertension complicated by atherosclerotic renovascular disease. In the treatment of elderly patients with heart disease, hypertension, or both, with ACE inhibitor, the possibility of coexisting renal artery stenosis should be considered. Renography is recommended as a reliable tool for detecting renal artery stenosis.

Purpose To clarify the influences of age and gender on normal fatty replacement of the thymus in childhood, adolescence, and early adulthood using chemical-shift MRI. Materials and Methods A total of 95 normal subjects (52 males and 43 females, mean age = 15.6 years, range = 7–25 years) who underwent chemical-shift MRI of the thymus were assessed prospectively. Signal intensity loss (SIL) of the thymus was determined by dividing the thymus/muscle ratio on the opposed-phase image by that on the in-phase image. We evaluated SIL for its correlation with age and gender, and assessed SIL of the thymus with uncommon morphological features. Results A significant correlation was found between SIL and age (r = 0.750, P < 0.001). There was no significant difference in SIL between the genders. No significant SIL was identified in any of the subjects aged 10 years or less. However, significant SIL was found in 70.8% of those aged 11–20 years, 100% of those aged 21 years or more, and 46.2% of subjects with uncommon morphological features of the thymus. Conclusion Chemical-shift MRI can depict physiologic fatty infiltration within the normal thymus in subjects over 11 years of age. It is crucial to correlate these normal age-related findings with clinical cases in order to avoid misinterpretation. J. Magn. Reson. Imaging 2005. © 2005 Wiley-Liss, Inc.

A 26-year-old female with intractable epileptic seizures was studied with I-123 iomazenil cerebral benzodiazepine receptor, I-123 IMP inter-ictal and Tc-99m ECD ictal cerebral blood flow SPECT. The ictal cerebral blood flow SPECT indicated the location of the seizures to be in the left temporal lobe, where increased regional cerebral blood flow was noted in marked contrast to the inter-ictal SPECT. Ictal electroencephalograms (EEGs) recorded with scalp and sphenoidal electrodes also suggested the left temporal lobe as the location of the seizures. On I-123 iomazenil SPECT, however, decreased benzodiazepine receptor density was demonstrated in the right temporal lobe. MRI showed mild atrophy and abnormal signal intensity in the right temporal lobe. Ictal EEGs recorded with intracranial electrodes revealed that abnormal electrical activity of the brain always emerged from the right temporal lobe and then propagated to the contralateral side. Based on the findings of intracranial EEGs, partial resection of the right anterior temporal lobe including hippocampus was performed. After the surgery, no seizure occurred. Pathological examination of the surgical specimens revealed hippocampal sclerosis. This case suggested that cerebral benzodiazepine receptor imaging with I-123 iomazenil can be helpful for correct localization of epileptogenic foci.

Objective To improve the estimation of 9 9 m Tc mercaptoacetyltriglycine clearance in the renal uptake method by optimizing the conditions of renal depth, background, threshold for renal boundary determination, and time interval for integrating renal counts. Methods Dynamic renal imaging was performed in 232 patients with dual energy window acquisition (main, 140′14 keV; sub, 122.5 t 3.5 keV). For drawing renal regions of interest (ROIs), cut-off methods with 50% and 70% of the highest renal pixel counts were used. For drawing the backgrounds, circumferential and lateral-inferior quadrant peri-renal ROIs were used. For setting the time interval, periods of 1-2, 1-2.5, 1.5-2.5, 1.5-3 and 2-3 min post-injection were used. For determining renal depth, three methods of a theoretical exponential function using scatter fraction, Tennesen's formula, and linear combination of scatter fraction and Tennesen's formula were used. The scatter fraction was calculated using the counts in renal ROIs in the two energy windows. Using every combination of these conditions, renal uptake was calculated. As a reference, one-sample clearance was calculated from a blood sample taken at 30 min post-injection following Bubeck's formula. According to the methods for estimating renal depth, three non-linear regression models were derived to convert renal uptake to clearance. Using one-sample clearance and integrated renal counts as dependent and independent variables, data were fitted to the models to determine the necessary constants. The correlations between the model estimated clearances and one-sample clearance were investigated. Results One-sample clearance ranged from 11 to 404 ml.min - 1 per 1.73 m 2 . More than half of the regression using renal depth determined by the scatter fraction alone failed to converge. Among the successfully converged regressions, all model estimated clearances showed significant correlations (P

We carried out a questionnaire survey of all radiological technology schools, to investigate the status of radiation safety education. The questionnaire consisted of questions concerning full-time teachers, measures being taken for the Radiation Protection Supervisor Qualifying Examination, equipment available for radiation safety education, radiation safety education for other departments, curriculum of radiation safety education, and related problems. The returned questionnaires were analyzed according to different groups categorized by form of education and type of establishment. The overall response rate was 55%, and there were statistically significant differences in the response rates among the different forms of education. No statistically significant differences were found in the items relating to full-time teachers, measures for Radiation Protection Supervisor Qualifying Examination, and radiation safety education for other departments, either for the form of education or type of establishment. Queries on the equipment used for radiation safety education revealed a statistically significant difference in unsealed radioisotope institutes among the forms of education. In terms of curriculum, the percentage of radiological technology schools which dealt with neither the shielding calculation method for radiation facilities nor with the control of medical waste was found to be approximately 10%. Other educational problems that were indicated included shortages of full-time teachers and equipment for radiation safety education. In the future, in order to improve radiation safety education at radiological technology schools, we consider it necessary to develop unsealed radioisotope institutes, to appoint more full-time teachers, and to educate students about risk communication.

The purpose of this study was to verify whether the accuracy of left ventricular parameters related to left ventricular function from gated-SPECT improved or not, using multivariate analysis.Methods: Ninety-six patients with cardiovascular diseases were studied. Gated-SPECT with the QGS software and left ventriculography (LVG) were performed to obtain left ventricular ejection fraction (LVEF), end-diastolic volume (EDV) and end-systolic volume (ESV). Then, multivariate analyses were performed to determine empirical formulas for predicting these parameters. The calculated values of left ventricular parameters were compared with those obtained directly from the QGS software and LVG.Results: Multivariate analyses were able to improve accuracy in estimation of LVEF, EDV and ESV. Statistically significant improvement was seen in LVEF (from r=0.6965 to r=0.8093, p

¶Background. There have been some reports that radiation necrosis can be controlled conservatively. There are rare cases showing progressive space-occupying radiation necrosis (PSORN). It is very difficult to control PSORN by conservative treatment. The purpose of this study was to evaluate the early diagnosis of those cases and the timing of surgery for patients with PSORN. Method. We have experienced some cases where quality of life was improved by the removal of PSORN after stereotactic radiosurgery (SRS) for brain metastases. Therefore, we evaluated retrospectively the diagnosis and treatment of six cases of symptomatic PSORN at approximately 6–12 months after SRS for metastatic brain tumours. Findings. In all six cases, on Magnetic Resonance Imaging with Gd contrast material (Gd-MRI), PSORN was revealed as a ring-like enhanced mass with large perifocal oedema coupled with the appearance of neurological deficit. Proton Magnetic Resonance Spectroscopy (1H-MRS) enabled us to differentiate PSORN from recurrence of metastases in all six cases. Single Photon Emission Computed Tomography with thallium-201 chloride (201TlCl-SPECT) enabled us to do this in four cases of the six. In four cases of the six, lesionectomy of the ring-like enhanced mass (PSORN) was performed, and in two of these cases the removal was performed within 4 weeks from the time when conservative treatment became ineffective, and the neurological deficit and perifocal oedema was improved as was the quality of life. However, in the other two patients who were left for more than 16 weeks, the deficit was gradually progressive. The two patients who did not receive lesionectomy were treated by conservative means with steroids and/or heparin and warfarin and they had progressive neurological symptoms. Interpretation. Although, the number of patients is small in this study, and more data will be needed, it is recommended that lesionectomy is performed at an early stage, if possible, when conservative management has failed.

The growing teratoma syndrome (GTS) secondary to a testicular nonseminomatous germ cell tumor has been well described since the first case was reported in 1982. In addition, radiological findings of male GTS have also reported in several studies; however, its occurrence secondary to an ovarian germ cell tumor is extremely rare. We experienced a 5-year-old girl who had GTS secondary to immature teratoma of the right ovary. In this article we present radiological findings of female GTS with clinical and pathological correlation.

Purpose: The purpose of this work was to evaluate the ability of breath-hold gadolinium-enhanced three-dimensional (3D) MR angiography to assess the invasion of the pulmonary vein and the left atrium by lung cancer. Method: Gadolinium-enhanced 3D MR angiography was performed in 20 consecutive patients with lung cancer. Results: At two sites with left atrial invasion shown by MR angiography, associated partial resection of the left atrium was performed. At five sites with invasion of the proximal pulmonary vein within 1.5 cm from the left atrium on MR, partial resection of the left atrium was performed at one site, and the pulmonary vein was resected at the intrapericardial portion at three sites. At two sites with invasion of the proximal pulmonary vein 1.5 cm more distal to the left atrium, the pulmonary vein was resected at the extrapericardial portion. Conclusion: Breath-hold gadolinium-enhanced 3D MR angiography is suitable for assessing invasion of the pulmonary vein and the left atrium by lung cancer.

A rats, benign congenital lymphangioma has been reported to ocour frequently in the neck and axilla, but rarely in the retroperitoneal space. We report a case of a retroperitoneal lymphangioma associated with hypoproteinemia caused by protein-loss into the tumor. In this case, lympho-scintigraphy with subcutaneously injected Tc-99m-human serum albumin (HSA) disclosed the communication between the tumor and the lymphatic system, and sequential abdominal scintigraphy with intravenously injected Tc-99m-HSA revealed the protein loss into the tumor. Abdominal scintigraphy with Tc-99m-HSA injected intravenously or subcutaneously is occasionally useful for determining the etiology of hypoproteinemia.

Experimentally we investigated the detection of lung cancer with N-isopropyl-p-I-123-iodoamphetamine (I-123 IMP). Various tumors including Lewis lung cancer were used as tumor models. Serial images were obtained. Biodistribution of Lewis lung cancer was performed. In Lewis lung cancer good visualization as in B-16 melanoma and high tumor accumulation were found with IMP. In conclusion, due to its greater accumulation almost equivalent to that in melanotic melanoma, I-123 IMP may have a role in the detection of lung cancer.

To evaluate the indication and advantages of venous sac embolization of pulmonary arteriovenous malformations (PAVMs) using interlocking detachable coils (IDCs).We performed percutaneous embolization in 12 PAVMs in four patients using IDCs, initially placed in the venous sac or at the feeding artery to prevent systemic migration of additional coils. We placed the IDCs in the venous sac in PAVMs with the following vascular architecture: the draining vein was larger than the feeding arteries and both vessels were interposed with the venous sac or there were short feeding arteries.Complete occlusion was achieved in all 12 PAVMs without significant complications. We deployed IDCs in the venous sac in eight PAVMs and in the feeding artery in four.Venous sac embolization may be beneficial in PAVMs with large out-flow vessels or short feeding arteries. IDCs are suitable for this procedure.

Stability and immunoreactivity of 186 Re-labeled monoclonal antibody were examined, and its in vivo kinetics was investigated in tumor-bearing Balb/c nu/nu female mice to assess the feasibility of using it in radioimmunotherapy (RIT). A murine IgG 1 , A7, against a 45 kD glycoprotein in human colon cancer was radiolabeled with 186 Re by using a chelating method with a mercaptoacetyltriglycine (MAG3). 186 Re-MAG3 complex was conjugated to A7 after esterification of 186 Re-MAG3 with tetrafluorophenol (TFP). The efficiency of 186 Re-MAG3-TFP production and the labeling efficiency of A7 were 51-59% and 57-60%, respectively. Immunoreactivity of purified 186 Re-MAG3-A7 was 68.2% at infinite antigen excess. In 0.9% NaCI at 4°C, the radioactivity (12.7 MBq/mg, 3.55 MBq/ml) dissociated with time from 186 Re-MAG3-A7 as a small molecular weight moiety because of autoradiolysis. The addition of ascorbic acid, 5 mg/ml, as a radioprotectant or storage at -80°C could effectively prevent the radiolysis of 186 Re-MAG3-A7 for 7 days. Immunoreactivity of Re-MAG3-A7, 6.70 MBq/mg (6.66 MBq/ml), stored in the presence of ascorbic acid was well retained up to 8 days after the preparation. In colon cancer xenografted mice, 31.0% of the injected dose/g of 186 Re-MAG3-A7 had accumulated in the tumors at 24 h postinjection. Estimated radiation dose to tumors was 14.9 cGy/37 kBq up to 8 days postinjection which was 12-fold greater than the whole-body radiation dose. These in vivo characteristics were superior to those of A7 labeled with radioiodine, affording greater therapeutic ratios than 131 I-A7. Because of the better image quality of 186 Re-MAG3-A7 as well as more favorable dosimetry, Re-MAG3-A7 would be a better choice for RIT of colon cancer than 131 I-A7. These results indicated the feasibility of RIT with 186 Re-MAG3-A7, though the prevention of radiolysis of the labeled antibody should be considered.

The diagnostic value of Tc-99m leukocyte imaging for evaluating disease activity and monitoring treatment response in ulcerative colitis was compared with that of colonoscopy. A total of 48 studies were performed in 28 patients with ulcerative colitis. Forty-six studies had both Tc-99m leukocyte imaging and colonoscopy within 2 weeks of each other, and the remaining two studies had only Tc-99m leukocyte imaging. In 46 studies, semiquantitative grading of colonic radioactivity by comparison with iliac crest marrow activity on radionuclide imaging correlated well with macroscopic grading based on Matts' criteria on colonoscopy. Fourteen (82%) of 17 studies with slight colonoscopic change showed a negative result on the radionuclide image. In 15 patients treated with glucocorticoids or leukapheresis, radionuclide imaging showed nearly the same statistical results as colonoscopy in monitoring treatment response. Tc-99m leukocyte imaging could be used as an alternative to colonoscopy to evaluate the disease activity of ulcerative colitis or to monitor the treatment response, although it is insensitive for detecting disease with only slight macroscopic changes.

We report discordant splenic uptake of Tc-99m colloid and Tc-99m heat-denatured red blood cells (RBC) which occurred in a 21-year-old female with candidiasis-endocrinopathy syndrome. Tc-99m colloid liver-spleen imaging showed no splenic uptake, suggesting the presence of functional asplenia. A subsequent Tc-99m heat-denatured RBC study clearly revealed a small spleen with preserved sequestrating function. These results may demonstrate that the qualitative dissociation of splenic functions in processing colloid and denatured RBC in functional asplenia: the sequestration function remains while the reticuloendothelial system is impaired.

An irregular, non-contrast-enhanced area shown on postcontrast computed tomography (CT) or postcontrast magnetic resonance imaging (MRI) in cases of non-Hodgkin's lymphoma (NHL) may indicate that the primary tumor has a high degree of malignancy. This study was planned to determine whether this indicated a poor prognosis. Fifty-six patients with NHL (32 males and 24 females) underwent diagnostic imaging; the internal characteristics of the primary lesion were evaluated retrospectively by 2 radiologists. Postcontrast CT with 2 mL/kg of contrast medium was performed in 46 cases during the equilibrium phase, and postcontrast MRI was also performed in 10 cases by the spin echo method following an 0.1 mmol/kg intravenous injection of gadopentetate. Ten (17.8%) of the 56 cases with NHL showed an irregular non-contrast-enhanced area. The 5-year survival rate for cases with homogeneous enhancement was 77.5%, while the actuarial survival rate at 44 months for cases with an irregular non-contrast-enhanced area was 25.4% (P

We synthesized a radiosensitizer KADTF, consisting of a hypoxic radiosensitizer, KU2280, bound to the side chain group of Mn-metalloporphyrin, which accumulates in tumor tissue. In the in vitro colony-forming activity test using HeLa cells, KADTF enhanced the effect of radiation under hypoxic conditions. Radiation therapy at 20 Gy, 1.5 h after infusion of KADTF (0.15 mM/kg), inhibited tumor growth more markedly than did a single radiation treatment. A clear tumor MR images of the SCCVII tumor was obtained at 1.5 h after administration of KADTF (0.1 mM/kg).

胃癌手術後の残胃十二指腸間にpouchを形成した空腸を間置する再建 (JPI法) を評価した. 術後の胸やけや下痢の出現頻度は, JPI法による再建例で, 従来のBillroth法による再建と比較して低率であった. 残胃からの食物排泄を核医学的に観察すると, JPI法では食物は残胃およびpouchに貯留し, 緩徐に十二指腸へと流出するのが認められ, 残胃からの排泄時間T1/2は, Billroth I法の29±6分, Billroth II法の50±37分に対し, JPI法では104±45分と有意に延長していた. 残胃内への胆汁逆流はBillroth法では全例に認められたが, JPI法では15%にみられるのみであり, 胆汁と食物の混和異常も, Billroth法に比較してJPI法では低率であった. 以上より, JPI法は従来のBillroth法よりも術後愁訴の少ない, より生理的な状態が得られる再建法と考えられた.

Purpose We hypothesized that the remnant of the primitive pulmonary venous plexus in the embryo provides a pathway for direct communication from each lobe of the lung to the mediastinum. We assessed the presence and location of these connections by using 64-row multidetector computed tomography (CT). Materials and methods This study was approved by the institutional ethics committee. First, we analyzed the multidetector row CT images of 120 normal lungs for the presence of septal structures between the pulmonary veins and the mediastinum and the extension of mediastinal fat into these septal structures. Second, we analyzed 62 patients with pneumothorax for the presence of cross-bridging structures in the pleural cavities. Results We frequently observed septal structures (36% to 77%) and the extension of mediastinal fat (8% to 56%) in the right apical segment, left apical posterior segment, both right and left anterior segments, right medial segment, and left inferior lingular segment. Cross-bridging structures were observed in 44% of right and 38% of left pneumothoraces and were noted in the right apical and posterior segments, left apical posterior segment, both anterior segments, right middle lobe, and left lingular segments. Septal and cross-bridging structures both showed a similar distribution pattern. Conclusions Venous septal structures in normal lungs and cross-bridging structures in pneumothoraces visualized on CT images suggest the presence of direct pathways from each lobe of the lung to the mediastinum.

A 66-year-old woman with congestive heart failure suspected to have multiple myeloma underwent bone scintigraphy. The bone scintigraphy using technetium-99m hydroxymethylene-diphosphonate showed the following interesting findings: absent skeletal uptake; increased gastrointestinal, myocardial, and soft tissue uptake; migration of radionuclide to bilateral pleural effusions. Histopathological examination revealed that the patient suffered from AL-type amyloidosis associated with multiple myeloma. Extraosseous uptake is often observed on bone scintigraphy in amyloidosis patients, but in many cases skeletal uptake is preserved. The simultaneous presentation of these findings is rare.

Ninety-six patients with various diffuse hepatic diseases were observed using both 99mTc colloid and 99mTc iminodiacetic acid (IDA), focusing on the potential etiologies of the disease process as well as its chronicity and severity. The presence of acute hepatic disease was more sensitively depicted with 99mTc IDA than with 99mTc colloid. In chronic hepatic disease, on the other hand, 99mTc colloid and 99mTc IDA demonstrated a similar sensitivity. The potential etiology of the disease process (differential diagnosis) and the chronicity of the disease could be evaluated better with 99mTc colloid. Among the patients with different stages of liver cirrhosis, however, 99mTc IDA significantly discriminated the severity of the hepatic disease. These results suggest that 99mTc IDA may be used to determine the degree of functional disorder in acute hepatic disease and evaluate the severity of diffuse hepatic disease, whereas 99mTc colloid can effectively evaluate the potential etiology and chronicity of the disease.

Summary 201Tl single photon emission computed tomography (SPECT) was evaluated in 170 patients suspected of having a malignant pulmonary lesion greater than 20 mm in diameter on the surgical specimen. Delayed SPECT (at 3 h after injection) visualized all of the 147 malignant pulmonary lesions and 16 of the 23 (69.6%) benign pulmonary lesions, and generally exhibited the lesion more clearly than the early SPECT images (at 15 min after injection). There was no significant difference in delayed ratio (uptake ratio of the lesion to the normal lung on delayed scan) among the various histological groups except between the adenocarcinoma and large cell carcinoma groups (P < 0.05), and no difference was noted between the malignant and benign lesions. However, in retention index (degree of retention in the lesion) a significant difference was noted between the malignant and benign lesions (P < 0.01), although there was no significant difference in this index among malignant different histology groups. These results indicate that this method is useful for visualizing malignant pulmonary lesions greater than 20 mm in diameter to exclude the possibility of malignancy in the lesions when no abnormal 201TI accumulation is observed. When the lesion shows abnormal 201Tl accumulation, the retention index seems to help differentiate malignant from benign lesions.

A simple, noninvasive method for the determination of extraction fraction and renal plasma flow in Tc-99m DTPA studies is presented. This method could be performed in conjunction with the measurement of glomerular filtration rate, providing additional information about renal plasma flow. Graphic analysis of the Patlak plot was employed for the determination of the unidirectional influx rate constant (ku) of Tc-99m DTPA from the blood to the kidney and the initial nonspecific distribution volume (Vn) in the kidney. The first pass extraction fraction was estimated from Ku and Vn, assuming a bolus input to the kidney. The glomerular filtration rate was measured by renal counting corrected for depth and dose. Using the estimated extraction fraction (EF) and glomerular filtration rate (GFR), the renal plasma flow (RPF) was calculated using the formula of RPF = GFR/EF. In a total of 76 kidneys in 38 patients (including 9 patients with normal renal function and without evidence of nephrourologic disease), the value of renal plasma flow showed good correlation with that of effective renal plasma flow measured by renal counting with I-131 orthoiodohippuran. There was a characteristic tendency for the extraction fraction to show a larger value as the renal plasma flow decreased. These results indicate that this method is valid for renal plasma flow estimation and the determinations of extraction fraction and renal plasma flow in Tc-99m DTPA studies is helpful as an adjunct to the measurement of glomerular filtration rate in order to adequately assess the pathophysiologic changes of renal disorders.

Two cases of papillary carcinoma of the thyroid are presented in which whole-body scans following therapeutic doses of iodine-131 revealed intense anterior mediastinal uptake. In both cases, the mediastinal uptake was absent from scans obtained after removal of the entire thymus. Histologically, the resected thymus glands showed hyperplasia and contained neither thyroid tissue nor metastatic foci of thyroid carcinoma. We therefore concluded that anterior mediastinal uptake of radioiodine may be caused by hyperplasia of the thymus.

A 27-year-old woman with progressive diaphyseal dysplasia (Camurati-Engelmann disease) received pamidronate and corticosteroid therapy for bone pain. During therapy, disease activity was assessed serially using bone scintigraphy with Tc-99m HMDP. With pamidronate administration, the bone pain became worse and diaphyseal uptake of Tc-99m HMDP increased, whereas corticosteroid administration improved the bone pain and reduced the diaphyseal uptake. In this case, pamidronate and corticosteroid produced different effects. Bone scintigraphy allowed an objective assessment of the response to these treatments, accurately reflecting clinical symptoms.

The current study was initiated to define whether Tc-99m leukocyte imaging, compared to In-111 chloride imaging, could provide additional information on the hematopoietic activity of the bone marrow in diffuse hematologic disorders. A total of 11 patients with hematologic disorders were studied both with Tc-99m leukocytes and In-111 chloride. One patient with myelofibrosis showed disparate tracer distribution in the bone marrow between the two; Tc-99m leukocyte uptake in the central marrow was highly decreased, whereas In-111 chloride showed expanded marrow. The disparate results of granuloid hypoplasia and erythroid hyperplasia obtained by bone marrow biopsy and aspiration in this patient were thought to give an explanation for the radionuclide findings. The remaining 10 patients showed similar tracer distribution in the marrow, and the observation of hematopoietic cellularity confirmed by bone marrow biopsy and aspiration correlated well with the radionuclide findings. These results demonstrate that Tc-99m leukocytes may be a potential imaging agent for evaluating hematopoietic activity in the bone marrow, in particular granulopoietic activity.

A 31-year-old woman visited an out-patient clinic, because of low-grade fever and general fatigue. She was referred to our hospital and admitted for examination of an abnormal shadow which had been found on the chest radiograph. She had experienced faint right lateral chest pain several times on the deep inspirations. Chest radiography showed a mass shadow with calcification in the right lower lung field on the mediastinal side. Chest radiographic computed tomography showed a 6x6 cm tumor in the right lung field. There were low-density areas with septae inside the tumor. Bone scintigraphy showed extremely high uptake of (99m)Tc-HMDP in the tumor. After surgical resection and pathological examination, we concluded that the tumor was an extensively calcified benign hemangioma of the diaphragm.

We report the case of a 25-year-old woman with systemic lupus erythematosus. She complained of headache and left hemiparesis and was admitted to our hospital. She was in a coma after admission. Brain MRI showed no abnormalities, but brain single photon emission computed tomography showed diffuse hyperperfusion in the right frontal and temporal lobes. The calculated measured regional cerebral blood flow in the right hemisphere was increased to 40 to 55 mL/100 g/min, and that in the left was within the normal range of 25 to 35 mL/100 g/min. Two months later, the hyperperfusion was disappeared. The hyperperfusion could be explained by inflammatory changes.

A 26-year-old woman, who had occasionally received an estrogen preparation for dysmenorrhea, was hospital; ized for closer evaluation of a large hepatic mass de/ tected incidentally by abdominal ultrasonography. To characterize the mass, liver imaging was performed using three imaging agents: Tc-99m phytate as a radiocolloid, Tc-99m pyridoxyl-5-methyl tryptophan (PMT) as a hepatobiliary agent, and Tc-99m DTPA galactosyl human serum albumin (GSA) as a radiolabeled neogly-coalbumin for the asialoglycoprotein receptor. Tc-99m PMT and Tc-99m GSA accumulated in the mass in a manner similar to the uptake in the normal liver parenchyma. On the other hand, Tc-99m phytate showed less accumulation than the other two agents did. Based on these findings, the diagnosis of focal nodular hyperplasia of the liver was strongly suggested. The mass was resected, and pathologic analysis confirmed the diagnosis of focal nodular hyperplasia.

The diagnostic values of hyperperfusion to the gallbladder fossa and the rim sign were retrospectively evaluated in 24 histopathologically proven cases of gallbladder disease. Although 12 of 13 patients (92%) with acute cholecystitis had nonvisualization of the gallbladder, the positive predictive value with this finding was 71%. However, when the finding was associated with hyperperfusion to the gallbladder fossa or the rim sign, the positive predictive value with both (90%) was markedly increased, compared to the prevalence ratio of 54%. Such a combination could be useful for preserving a high positive predictive value in the diagnosis of acute cholecystitis.

Solitary fibrous tumors (SFTs) of the pleura are rare soft-tissue tumors that are presumed to be of mesenchymal origin. Most SFTs are histologically benign, but up to 20% of SFTs may be malignant. In addition, malignant transformation may occur within histologically benign SFTs, though it is rare. However, it is difficult to diagnose malignant SFTs of the pleura by means of conventional computed tomography and magnetic resonance imaging (MRI). In this article we present the first case of malignant SFT of the pleura in an 81-year-old man in which the apparent diffusion coefficient (ADC) value and ADC map based on diffusion-weighted MRI were very useful for identifying malignant transformation.

To prospectively evaluate chemical shift magnetic resonance (MR) imaging for differentiating thymic hyperplasia from tumors of the thymus gland.The institutional review board approved this study; informed consent was obtained and patient confidentiality was protected. The authors assessed 41 patients (17 male, 24 female; age range, 16-78 years) in whom thymic lesions were seen at chest computed tomography. Patients were assigned to a hyperplasia group (n=23) (18 patients with hyperplastic thymus associated with Graves disease and five with rebound thymic hyperplasia) and a tumor group (n=18) (seven patients with thymomas, four with invasive thymomas, five with thymic cancers, and two with malignant lymphomas). T2-weighted fast spin-echo and T1-weighted in-phase and opposed-phase MR images were obtained in all patients and visually assessed. A chemical shift ratio (CSR), determined by comparing the signal intensity of the thymus gland with that of the paraspinal muscle, was calculated for quantitative analysis. Mean CSRs for the patient groups and subgroups were analyzed by using Welch t and Newman-Keuls tests. P.05 indicated a significant difference.The thymus gland had homogeneous signal intensity in all 23 patients in the hyperplasia group and in 12 of the 18 patients in the tumor group. The mean CSR (+/- standard deviation) was 0.614 +/- 0.130 in the hyperplasia group and 1.026 +/- 0.039 in the tumor group. Mean CSRs in the patients with a hyperplastic thymus and Graves disease, rebound thymic hyperplasia, thymoma, invasive thymoma, thymic cancer, and malignant lymphoma were 0.594 +/- 0.120, 0.688 +/- 0.154, 1.033 +/- 0.043, 1.036 +/- 0.040, 1.020 +/- 0.044, and 0.997 +/- 0.010, respectively. The difference in CSR between the hyperplasia and tumor groups was significant (P.001). Mean CSRs in the hyperplasia subgroups were lower than those in the tumor subgroups (P.001). All hyperplasia group patients had an apparent decrease in thymus gland signal intensity at chemical shift MR imaging; no tumor group patients had a decrease in thymus gland signal intensity.Chemical shift MR imaging can be used to differentiate thymic hyperplasia from thymic tumors.

A 19-year-old man with a double-chambered right ventricle (DCRV) and an associated ventricular septal defect was admitted to the hospital for surgical correction. Preoperative study of myocardial perfusion with Tc-99m tetrofosmin SPECT depicted the two chambers of the right ventricle. There was a substantial differential in the radioactive uptake between these two chambers. The inflow and outflow chambers with different peak-pressures (94 and 18 mm Hg) showed different uptakes reflecting the pressure difference, which was intense in the inflow chamber and weak in the outflow.

The aim of this study was to identify the brain areas that control urinary continence in healthy men by 99mTc-hexamethylpropyleneamine oxime (99mTc-HMPAO) SPECT.SPECT scans were performed on 15 right-handed healthy male volunteers, 24-45 y old. Each subject was scanned twice without movement in a supine position, and 444 and 555 MBq 99mTc-HMPAO were separately injected intravenously during the following 2 conditions: resting state with an empty bladder and urine-withholding state with a full bladder. The final image during urine withholding was obtained by subtracting the first scan data from the second scan data. The images were analyzed by statistical image analysis software and displayed on Z-score images at a significance threshold of P0.05 with correction for multiple comparisons.In the urine-withholding state, as compared with resting, there was a significant increase in tracer activity in the bilateral inferior frontal gyri and the right superior and the middle temporal gyri. Among the regions, the right inferior frontal gyrus was distinctly prominent. When the threshold value was decreased to P0.005 without correction, there was a vast network of cortical and subcortical regions involved during urine withholding.Our results suggest that the right inferior frontal gyrus plays an important role in brain control of urinary continence. This study also suggests that brain control of continence can be confirmed by statistical image analysis software using SPECT.

We carried out a questionnaire survey to determine the actual situation of radiation safety management measures in all medical institutions in Japan that had nuclear medicine facilities. The questionnaire consisted of questions concerning the evaluation of shielding capacity; radiation measurement; periodic checks of installations, equipment, and protection instruments; and the calibration of radiation survey meters. The analysis was undertaken according to region, type of establishment, and number of beds. The overall response rate was 60 percent. For the evaluation of shielding capacity, the outsourcing rate was 53 percent of the total. For the radiation measurements of "leakage radiation dose and radioactive contamination" and "contamination of radioactive substances in the air," the outsourcing rates were 28 percent and 35 percent of the total, respectively (p