Forgot your password?
New user?
New Window Opens on the Secret Life of Microbes: Scientists Develop First Microbial Profiles of Ecosystems
CAS announces the release of SciFinder Scholar for Mac OS X
Press Releases
Press Releases
| Check out our New Publishers' Select for Free Articles |
Annals of Nuclear Medicine (v.21, #5)
Relationship between 99mTc-GSA scintigraphic indices of liver function reserve and portal circulation in patients with chronic liver disease by Hisato Osada; Norinari Honda; Takeo Takahashi; Shinya Oku; Atsushi Abe; Wataru Watanabe; Takemichi Okada; Hitoshi Ohno; Mikito Hondo; Keiichiro Nishimura (pp. 245-249).
In order to predict the prognosis or complications of portal hypertension in patients with chronic liver disease, it is important to evaluate both hepatic functional reserve and portal circulation. On 99mTc-galactosyl human serum albumin (99mTc-GSA) scintigraphy, the index of blood clearance (HH15) and receptor index (LHL15) have been widely used to evaluate the hepatic functional reserve. However, the relationship between these indices and portal circulation is unknown. The purpose of this study was to examine the relationship between HH15 and LHL15 and portosystemic shunts evaluated with arteriographic portography or esophagogastroduodenoscopy.A total of 82 patients with chronic liver disease (mean age, 66.7 years) who underwent 99mTc-GSA scintigraphy, arteriographic portography, and esophagogastroduodenoscopy were enrolled. HH15 and LHL15 were obtained from dynamic 99mTc-GSA scintigraphy. The patients were divided into three groups according to the arteriographic portography findings: group 1, no portal collateral circulation; group 2, mild collateral development; and group 3, moderate to severe collateral development. They were also divided into three groups based on the esophagogastroduodenoscopic findings: group A, no varices; group B, small-caliber varices; and group C, enlarged varices. The Kruskal–Wallis test was used to compare each index among these groups. Receiver operating characteristic (ROC) analysis was used to determine whether each index was an indicator for the presence of portosystemic shunts.Both HH15 and LHL15 differed significantly between groups 1 and 2 and between groups 1 and 3. However, only HH15 differed significantly between groups A and B and between groups A and C. On the basis of the ROC analysis, the HH15 threshold value of 0.62 yielded both excellent sensitivity (83.9%) and specificity (84.6%) for the presence of portosystemic shunts, as evaluated with arteriographic portography. The HH15 threshold value of 0.64 yielded both good sensitivity (66.1%) and specificity (69.2%) for the presence of portosystemic shunts, as evaluated with esophagogastroduodenoscopy, whereas no adequate threshold value of LHL15 was found for the presence of portosystemic shunts.HH15 is a potent indicator of the presence of portosystemic shunts in chronic liver disease.
Keywords: 99mTc-GSA; Portal hypertension; Portal circulation; Varix; Chronic liver disease
Does supplementation of contrast MR imaging with thallium-201 brain SPECT improve differentiation between benign and malignant ring-like contrast-enhanced cerebral lesions? by Tamotsu Kita; Katsumi Hayashi; Masayoshi Yamamoto; Toshio Kawauchi; Ikuko Sakata; Yoshie Iwasaki; Shigeru Kosuda (pp. 251-256).
To determine whether thallium-201 (201Tl) brain single photon emission computed tomography (SPECT) could supplement magnetic resonance (MR) imaging diagnostic information by visual comparison of two separate data sets from patients with ring-like contrast-enhanced cerebral lesions.A combination of MR imaging and 201Tl brain SPECT sets obtained from 13 patients (10 men, 3 women) ranging in age from 26 years to 86 years (mean 61.0 years) were retrospectively reviewed. A total of 12 patients had a solitary lesion, and the others had multiple lesions. All but two intracranial foci were pathologically confirmed. The final diagnoses were six glioblastomas, two cerebral metastases from lung cancer, and one each of abscess, resolving hematoma, primary central nervous system lymphoma, toxoplasmosis, and radiation necrosis. The two separate image formats (MR images and SPECT) were shown to ten readers with practical experience. All of the MR images for each patient were shown to each reader first. After interpreting them, the readers were shown the SPECT images. Images were scored in terms of how benign or malignant the foci were on a 5-point scale from “definitely benign” to “definitely malignant.”The improvement in the performance of all ten readers was from 67.7% to 93.8% in mean accuracy (P = 0.0028) and from 0.730 to 0.971 in mean Az value (P = 0.0069) after they were shown the 201Tl brain SPECT images. 201Tl brain SPECT should substantially increase confidence in the diagnosis of intracranial lesions with ring-like contrast enhancement when MR imaging does not permit differentiation between benign and malignant disease.
Keywords: 201Tl chloride; Brain SPECT; Intracranial lesion; Ring-like contrast enhancement
Effectiveness of treatment with donepezil hydrochloride and changes in regional cerebral blood flow in patients with Alzheimer's disease by Tsunetaka Yoshida; Sangkil Ha-Kawa; Masafumi Yoshimura; Kenji Nobuhara; Toshihiko Kinoshita; Satoshi Sawada (pp. 257-265).
The objective of this study was to elucidate the relationship between the effects of donepezil hydrochloride (donepezil) and cerebral blood flow, and to evaluate the usefulness of cerebral blood flow imaging in assessing and predicting treatment effectiveness.The subjects were 29 outpatients (12 men and 17 women; age 50–82 years; mean age 69.2 years), who had received a diagnosis of Alzheimer's disease (AD). Efficacy was evaluated before donepezil administration; after 1 month, 3 months, and 6 months of drug administration; and at 1 year after completion of administration using the Japanese version of the Alzheimer's disease assessment scale-cognitive subscale (ADAS-cog), as a measure of cognitive function. The ADAS-cog has been frequently used to evaluate cognitive function in AD patients. Patients whose ADAS-cog scores improved by 3 or more points during the observation period were classified as responders, and those with no improvement were classified as nonresponders. 123I-IMP was used for single photon emission computed tomography cerebral blood flow scintigraphy.On the basis of ADAS-cog score improvement, 22 of the 29 patients were responders (7 men and 15 women; age 50–82 years; mean age 69.0 years) and seven were nonresponders (5 men and 2 women; age 61–80 years; mean age 70.0 years). The results indicate that a difference in cerebral blood flow responsiveness after 1 month of treatment distinguishes responders from nonresponders. After 1 month, blood flow was significantly decreased in all regions of nonresponders, whereas significant increases in blood flow were seen in the anterior frontal lobe and parietal lobe of responders. At that time point, blood flow in the basal ganglion differed significantly between the two groups, indicating that this difference in responsiveness after 1 month of treatment may distinguish responders from nonresponders.In cognitive function testing, the group that exhibited a complete response showed improvement primarily in parameters reflecting frontal lobe function. Complete responders also showed significantly greater blood flow increases in the basal ganglion and thalamus early during the treatment period. This indicates that the drug responsiveness of the basal ganglion and thalamus affects frontal lobe function and distinguishes complete responders from patients who do not exhibit such a response.
Keywords: Donepezil; Cerebral blood flow; SPECT; Alzheimer's disease; Cognitive function
Myocardial kinetics of 201Thallium, 99mTc-tetrofosmin, and 99mTc-sestamibi in an acute ischemia–reperfusion model using isolated rat heart by Kenji Fukushima; Mitsuru Momose; Chisato Kondo; Kiyoko Kusakabe; Hiroshi Kasanuki (pp. 267-273).
201Thallium (TL), 99mTc-tetrofosmin (TF), and 99mTc-sestamibi (MIBI) are extensively used as myocardial perfusion agents. The objective of the present study was to evaluate their kinetics under acute ischemia–reperfusion.Isolated rat hearts, perfused by the Langendorff method at a constant flow rate of 10 ml/min, were allotted to normal control, mild ischemia, and severe ischemia groups, in which 20-min tracer wash-in was conducted followed by a 25-min tracer washout. No-flow ischemia (15 min for mild ischemia groups; 30 min for severe ischemia groups) was induced before conducting wash-in and washout in the ischemia groups. Whole-heart radioactivity was determined with an external gamma detector. Myocardial flow rate (K 1, ml/min) and clearance rate (k 2, min−1) were calculated. K 1TL, K 1TF, and K 1MIBI decreased according to the severity of ischemia (K 1TL 5.32 ± 0.53, 4.76 ± 0.70, and 1.44 ± 0.59; K 1TF 3.80 ± 0.70, 2.73 ± 0.99, and 1.09 ± 0.45; and K 1MIBI 3.45 ± 1.10, 2.15 ± 0.82, and 1.05 ± 0.13, in the normal control, mild, and severe ischemia groups, respectively). K 1 was significantly higher for TL than for the 99mTc tracers (P < 0.05), but the 99mTc tracers had equivalent K 1 values. k 2TL increased significantly (P < 0.05) in the ischemia groups (k 2TL 0.062 ± 0.013, 0.11 ± 0.045, and 0.12 ± 0.035), but showed no significant difference between the ischemia groups. k 2MIBI and k 2TF were significantly (P < 0.05) lower than k 2TL and increased significantly (P < 0.05) in the severe ischemia group (k 2TF 0.0056 ± 0.0022, 0.0037 ± 0.0015, and 0.024 ± 0.015; and k 2MIBI 0.00072 ± 0.0011, 0.00038 ± 0.00076, and 0.042 ± 0.034). k 2MIBI was significantly (P < 0.05) lower than k 2TF in the normal control and mild ischemia groups.Tracer extraction was higher for TL than for the 99mTc tracers and all tracers decreased according to the severity of ischemia–reperfusion in the three tracer groups. The clearance kinetics of not only MIBI but also TF is possibly useful for the evaluation of the severity of ischemia, and the Langendorff method and a methodological approach by continuous determinations of radioactivity may serve for the quantitative analysis of tracer kinetic profiles.
Keywords: 201Thallium; 99mTc-tetrofosmin; Sestamibi; Myocardial kinetics; Isolated rat heart
The role of Tc-99m (V) DMSA scintigraphy in the diagnosis and follow-up of lung cancer lesions by Eser L. Ergün; Pelin Ö. Kara; Gonca K. Gedik; Ayşe Kars; Alev Türker; Biray Caner (pp. 275-283).
To define the role of Tc-99m (V) dimercaptosuccinic acid (DMSA) scanning in the detection of lung cancer (LC) and its metastases, and monitoring the response of LC lesions (LCL) to chemo/radiotherapy (TH). Tc-99m (V) DMSA whole-body scans, planar thorax views, and thorax Single-photon emission computed tomography (SPECT) images were obtained both 30 min (early) and 5 h (late) after Tc-99m (V) DMSA administration in 12 small/nonsmall cell LC patients (11 men, 1 woman; mean age 59 years). Five patients also had bone scans. The same scintigraphic protocol was performed in 7 of 12 patients, 3 weeks after first-line TH. TH response was evaluated visually in all LCL and semiquantitatively in primary tumors (PT) of six patients, by comparing the tumor uptake ratios (TUR) of pre-TH and post-TH Tc-99m (V) DMSA SPECT [TUR = mean counts of region of interests (ROI) in PT/mean counts in contralateral ROI]. In seven patients, a 6-month survival was determined.Tc-99m (V) DMSA accumulated in 34 LCL (11 PT, 19 bone metastases, 1 suprarenal mass, 1 axillary node, 2 supraclavicular nodes). A total of 11 patients displayed Tc-99m (V) DMSA uptake in LCL and one patient did not show uptake. In six patients, SPECT imaging showed deeply located PT in the lung parenchyma better than planar views. In five patients, both planar and SPECT views revealed peripherally located PT in the lungs. Early scans showed 18 LCL and late scans displayed all the LCL. Nine bone metastases on pre-TH Tc-99m (V) DMSA scans revealed matched areas of increased Tc-99m methylene diphosphonate (MDP) uptake on bone scans; six bone metastases were additionally detected on Tc-99m (V) DMSA scans when compared with bone scans, and four bone metastases on Tc-99m (V) DMSA scans could not be compared with bone scans because bone scan was not performed. In one patient, Tc-99m (V) DMSA scans became positive for bone metastases on post-TH later than the bone scans for some of the bone metastases. Neither planar nor SPECT imaging showed mediastinal lesions defined on thorax CT in nine patients. On TH monitoring, 17 LCL showed diminished Tc-99m (V) DMSA uptake, one disappeared, four were unchanged, three displayed increased uptake, and five new lesions were established. Of the six patients, TUR in PT increased in two (one survived), decreased in one (exitus), was unchanged in two (two exitus) on post-TH scans, and PT totally disappeared in one (survived) patient.Tc-99m (V) DMSA scans are useful in detecting LCL, except for those around the blood pool regions, making it a promising modality to monitor TH response. Obtaining a single fifth hour late Tc-99m (V) DMSA scan is appropriate. SPECT should be applied to all patients for the detection of deeply located lesions.
Keywords: Tc-99m (V) DMSA; Lung cancer; Scintigraphy
The value of Tc-99m (V) dimercaptosuccinic acid in detecting intra-abdominal infection: compared with gallium scan by Wan-Yu Lin; Guang-Uei Hung; Te-Hsin Chao (pp. 285-291).
Gallium-67 (Ga-67) and labeled leukocytes are useful in the detection of an unknown infectious source. However, the delay in the diagnosis of a Ga-67 citrate scan (gallium scan) and the complicated labeling technique of a leukocyte scan are major drawbacks to their clinical use. Recently, Tc-99m (V) dimercaptosuccinic acid (DMSA) has been found to be very useful in the detection of infection. Tc-99m (V) DMSA is inexpensive, easy to prepare, and provides a result within hours. In this study, we evaluated the potential of Tc-99m (V) DMSA scan (DMSA scan) in the detection of intra-abdominal infection.A total of 33 patients who suffered from an unknown cause of fever after colorectal surgery were enrolled in this study. All patients received both a gallium scan and a DMSA scan. DMSA scintigraphy was performed 3–4 h after an injection of 740 MBq (20 mCi) of Tc-99m DMSA. After completion of the DMSA image, 111 MBq (3 mCi) of Ga-67 citrate was injected intravenously. Gallium scintigraphy was performed after 24 h and later as needed.Of the 33 patients, 17 (51.5%) were diagnosed with intra-abdominal abscesses. For DMSA scans, the sensitivity, specificity, and overall accuracy were 88.2%, 93.7%, and 90.9%, respectively. For gallium scans, the diagnostic sensitivity, specificity, and accuracy were 100%, 87.5%, and 93.9%, respectively. No statistical difference was found in the diagnostic accuracy between these two diagnostic modalities using Fisher's exact test.DMSA scan is a useful alternative to gallium scan in the detection of intra-abdominal infection in patients with colorectal surgery because Tc-99m DMSA is inexpensive, easy to prepare, and most importantly the result can be obtained within hours.
Keywords: Tc-99m(V) DMSA; Colorectal surgery; Abdominal infection; Gallium scan
Evaluation of brain tumor recurrence by 99mTc-tetrofosmin SPECT: a prospective pilot study by George A. Alexiou; Andreas D. Fotopoulos; Athanasios Papadopoulos; Athanasios P. Kyritsis; Konstantinos S. Polyzoidis; Spyridon Tsiouris (pp. 293-298).
The differentiation between brain tumor recurrence and post-irradiation injury remains an imaging challenge. Computed tomography (CT) and magnetic resonance imaging (MRI) cannot always distinguish between the two. Although glioma cell line studies substantiated a plausible imaging superiority of 99mTc-tetrofosmin (99mTc-TF) over other radiopharmaceuticals, little has been reported on its in vivo imaging properties. We assessed 99mTc-TF single-photon emission CT (SPECT) in cases where morphologic brain imaging was inconclusive between recurrence and radionecrosis.A total of 11 patients (7 men, 4 women) were evaluated. The initial diagnosis was glioblastoma multiforme (4), anaplastic astrocytoma (1), anaplastic oligodendroglioma (3), grade-II astrocytoma (2), and low-grade oligodendroglioma (1). All patients had been operated on and then received adjuvant external-beam radiotherapy. After a mean follow-up period of 25 months, there was clinical suspicion of recurrence, for which 99mTc-TF SPECT was performed.In 8/11 cases, an abnormally increased tracer uptake appeared in the region that CT and/or MRI indicated as suspicious; in half of these cases, recurrence was confirmed histologically after surgery and in the other four by growth of the lesion over a 6-month follow-up period, and clinical deterioration. The remaining 3/11 patients had faint tracer uptake in the suspicious region, compatible with radiation injury; these lesions remained morphologically unaltered in a mean 12-month follow-up period, with no clinical deterioration in the patient's condition, a course strongly favoring the diagnosis of radiation injury.Metabolic brain imaging by 99mTc-TF could offer useful information in the workup of treated brain tumors, where radiomorphologic findings between recurrence and radionecrosis are inconclusive.
Keywords: Radiation injury; Glioma; Recurrence; SPECT; 99mTc-Tetrofosmin
F-18 FDG PET/CT imaging of low-grade mucoepidermoid carcinoma of the bronchus by Taichiro Ishizumi; Ukihide Tateishi; Shun-ichi Watanabe; Tetsuo Maeda; Yasuaki Arai (pp. 299-302).
Mucoepidermoid carcinomas in the bronchial tree are extremely rare tumors. Such tumors are classified into low-grade and high-grade on the basis of histological criteria. Fluorine-18-fluorodeoxyglucose positron emission tomography (F-18 FDG PET) is a useful technique for the evaluation of pulmonary lesions; however, to our knowledge, F-18 FDG PET findings in mucoepidermoid carcinoma of the bronchus have been described in only a few cases. Identifiable focal F-18 FDG uptake has been reported in high-grade mucoepidermoid carcinoma, but it is unclear whether F-18 FDG accumulates in low-grade mucoepidermoid carcinoma. Here, we present the case of a 37-year-old woman, with pathologically proven low-grade mucoepidermoid carcinoma, who underwent high-resolution computed tomography (CT) and F-18 FDG PET/CT before treatment.
Keywords: Mucoepidermoid carcinoma; Low-grade tumor; F-18 FDG PET/CT; Lung
Positron emission tomographic findings in a tuberculous brain abscess by Kyusik Kang; Ilhan Lim; Jae-Kyu Roh (pp. 303-306).
Several case reports and studies have described the positron emission tomographic (PET) findings of intracranial tuberculomas and bacterial brain abscesses. However, to our knowledge, the PET pattern of a tuberculous brain abscess has not been previously described. We report the case of a diabetic heavy drinker with a left parietal tuberculous abscess. 18F-fluoro-2-deoxyglucose (FDG)-PET scans showed intense FDG uptake at the abscess periphery, where contrast enhancement was observed on a magnetic resonance image. FDG uptake was reduced within the abscess cavity and in the adjacent cerebral cortex. The possibility of a tuberculous brain abscess should be considered when FDG accumulates at the periphery of a ring-enhancing lesion in a chronically ill or immunocompromised patient.
Keywords: Positron emission tomography; Tuberculous brain abscess; Diagnosis; 18F-fluoro-2-deoxyglucose; Ring-enhancing mass
Whole-body iodine-131 metaiodobenzylguanidine imaging for detection of bone metastases in patients with paraganglioma: comparison with bone scintigraphy by Tetsuya Inoue; Keiichiro Yoshinaga; Koichi Morita; Tohru Shiga; Kakuko Kanegae; Kenji Hirata; Shozo Okamoto; Nagara Tamaki (pp. 307-310).
Iodine-131 metaiodobenzylguanidine (131I-MIBG) therapy is an effective treatment for patients with malignant paraganglioma for which surgical resection is not indicated. We performed high-dose 131I-MIBG therapy on two patients with malignant paraganglioma and multiple bone metastases. The bone metastases were diagnosed by magnetic resonance imaging (MRI). Metastatic bone lesions were evaluated by whole-body 131I-MIBG imaging and bone scintigraphy. Whole-body 131I-MIBG imaging showed extensive metastatic bone lesions, whereas conventional bone scintigraphy did not. There was a remarkable discrepancy between 131I-MIBG imaging and bone scintigraphy in the diagnosis of metastatic bone lesions of malignant paraganglioma in our two patients. High-dose 131I-MIBG imaging may detect early stages of bone metastases, compared with bone scintigraphy, in patients with malignant paraganglioma.
Keywords: Paraganglioma; Bone metastases; 131I-MIBG therapy; Bone scintigraphy
Different findings in Tc-99m MDP bone scintigraphy of patients with sickle cell disease: report of three cases by Sevim S. Cerci; Harun Suslu; Celal Cerci; Mustafa Yildiz; Feride M. Ozbek; Tansel A. Balci; Ahmet Yesildag; Duran Canatan (pp. 311-314).
Sickle cell anemia is an inherited disorder caused by abnormal hemoglobin, the S hemoglobin. Although vaso-occlusive crises can occur virtually in any organ, they are particularly common in the bony skeleton of affected patients. Bone marrow necrosis, bone infarcts, osteomyelitis, and aseptic necrosis are common complications in patients with sickle cell disease. Beside these abnormalities of the skeletal system, diffuse micro or macro calcification resulting from both splenic infarction and repeated vaso-occlusive episodes in the kidneys can be shown by technetium-99m methylenediphosphonate (Tc-99m MDP) bone scintigraphy. We present here the different osseous and extraosseous abnormalities noted on bone scintigraphies of three patients with sickle cell anemia.Whole-body bone scan was performed after injecting 740 MBq of Tc-99m MDP in three patients with sickle cell disease.Tc-99m MDP whole-body image of the first patient showed non-uniform uptake in the anterior and posterior aspects of multiple ribs and bilateral femurs and tibias that was attributed to repetitive infarcts. Additionally, increased activity in shoulders, right elbow, and right knee was consistent with arthritis. Tc-99m MDP image of the second patient demonstrated avascular necrosis of the left femoral head and diffuse activity in the enlarged kidneys. Increased activity in the spleen that was attributed to repetitive infarcts was visualized in bone scan of the third patient.In light of the findings in these cases, bone scintigraphy is a reliable imaging method in detecting both osseous and extraosseous abnormalities of sickle cell disease and may be used initially.
Keywords: Sickle cell disease; Tc-99m MDP bone scintigraphy; Osseous; Extraosseous abnormalities