PURPOSE: The authors investigated the ability of cardiac blood pool clearance rates(CBCR) of 99mTc-DiSiDA in the measure merit of functioning hepatocyte mass. MATERIALS AND METHODS: We measured the volume of Iobectomized liver after completion of postoperative scanning with CBCR of 99rnTc-DISIDA in 5 rabbits who the functional hepatic Iobectomy performed by ligation of hepatic artery, portal vein and biliary tracts. Regarding the measurement of CBCR of 99mTc-DISIDA, we set the time which was decreased to the half of the clearance amount of the cardiac radioactivity by hepatic extraction of 99mTc-DISIDA at the point of 50 sec after the renal peak of the radioactivity to prevent confusing with the blood dilution of the radioactivity, that have called DI-K50. RESULTS: The results were followed that the volumes of the functional hepatic Iobectomy in 5 rabbits were 25%, 25%, 41%, 52%, 75% and the residual functioning hepatocyte masses measured by CBCR of 99rnTc-DISIDA were preserved to 75. 1%, 70. 8%, 63. 0%, 52. 2%, 30. 8% respectively. CONCLUSION: we made decision that CBCR of 99rnTc-DISlDA was useful to evaluate the functioning hepatocyte mass.
Biliary Tract ; Hepatic Artery ; Hepatocytes* ; Ligation ; Liver ; Portal Vein ; Rabbits ; Radioactivity ; Technetium Tc 99m Disofenin*

No abstract available.

PURPOSE:A retrospective study was performed to assess the efficacy of MRI in evaluation of therapeutic response of bone lymphoma. MATERIALS AND METHODS:We reviewed 17 cases of bone lymphoma on MRI that were follow-up studies during or after therapy. Among them, the cases with contrast study during therapy were 5, and those after therapy were 6. The four findings of follow-up MRI considered representative of improvement of bone lymphoma were the decreased size of tumor mass, the decreased signal intensity on T2-weighted images, the increased signal intensity of the tumor on T1 -weighted images, and the decreased or absent enhancement of post-contrast T1 -weighted images. RESULTS: The findings of improvement on T1 and T2-weighted images were shown in 50%(7/14) during therapy and 85.7%(12/14) after therapy. Those On post-contrast T1 -weighted images were shown in 20%(1/5) during therapy and 50%(3/6) after therapy. CONCLUSION:On MRI, both findings of the decreased signal intensity on T2-weighted images and the increased signal intensity of on T1 -weighted images of the tumor were significant in evaluating therapeutic response of bone lymphoma.
Follow-Up Studies ; Lymphoma* ; Magnetic Resonance Imaging ; Retrospective Studies

urpose: Misonidazole is a radiosensitizer that binds in hypoxic cells. The purpose of this study was to find out the feasibility of I-131-Iodomisonidazole (IMISO) for imaging of tumor hypoxia. MATERIALS AND METHODS: Tosyl precursor was dissolved in acetonitrile and I-131-NaI was added to synthesize IMISO. Balb/c mice inoculated with CT-26 adenocarcinoma were injected with IMISO. Mice were sacrificed at 1,2,4,24 hr and % of injected dose per gram of tissue (%ID/g) was determined. For scintigraphy and MRI, mouse bearing CT-26 adenocarcinoma was administered with IMISO and imaging was performed 4 hr after. Then, mouse body was fixed and microtomized slice was placed on radiographic film for autoradiography. RESULTS: %ID/g of tumor was 1.64 (1h), 0.98 (2h), 0.85 (4h) and 0.20 (24h), respectively. At 24h, %ID/g of tumor was higher than that of all other tissues except thyroid. Tumor to muscle ratio increased with time and tumor to blood ratio also increased with time and reached 1.53 at 24 hr. On autoradiogram, tumor was well visualized as an increased activity in central hypoxic area of the tumor which corresponds to the area of high signal intensity on T2-weighted MR image. On scintigraphy, tumor uptake was visualized. CONCLUSION:: This RESULTS suggest that IMISO may have a potential for tumor hypoxia imaging in mouse model. However, further study is needed to improve it's localization in tumor tissue and to achieve acceptable images of tumor hypoxia.
Adenocarcinoma* ; Animals ; Anoxia* ; Autoradiography ; Magnetic Resonance Imaging ; Mice* ; Misonidazole ; Radionuclide Imaging ; Thyroid Gland ; X-Ray Film

Molecular imaging aims to visualize the cellular and molecular processes occurring in living tissues, and for the imaging of specific molecules in vivo, the development of reporter probes and dedicated imaging equipment is most important. Reporter genes can be used to monitor the delivery and magnitude of therapeutic gene transfer, and the time variation involved. Imaging technologies such as micro-PET, SPECT, MRI and CT, as well as optical imaging systems, are able to non-invasively detect, measure, and report the simultaneous expression of multiple meaningful genes. It is believed that recent advances in reporter probes, imaging technologies and gene transfer strategies will enhance the effectiveness of gene therapy trials.
Animals ; Apoptosis/physiology ; Contrast Media ; Diagnostic Imaging/*methods ; Gene Expression/physiology ; Gene Therapy ; Genes, Reporter/physiology ; Human ; Molecular Biology/*methods ; Neovascularization, Physiologic/physiology ; Rats

The World Health Organization classification divides thymomas according to morphology, epithelial component, and cell atypia. They are grouped into 3 large subgroups: low-risk thymomas (types A, AB, and B1), high-risk thymomas (types B2 and B3), and thymic carcinomas. Tumor subtype represents an independent prognostic factor, which determines therapeutic decision. All thymomas show some degree of 18 F-FDG uptake, which tends to increase with the grade of malignancy; this is related to glucose transporter 1 (GLUT1) expression. This review collects all types of thymomas with illustrative images and provides a guide to get familiar with histological characteristics of the lesions and have them in mind because, even imaging findings can overlap among subtypes, certain characteristics can be combined to make an accurate diagnosis based on 18 F-FDG PET-CT findings.

PURPOSE: I-131 labeled (2'-deoxy-2-iodo-p-D-arabinofuranosyl) adenine (IAD) may be involved in DNA synthesis during active proliferation of tumor cells. We conducted this study to find out the biodistribution of IAD and its feasibility for scintigraphic tumor imaging. MATERIALS AND METHODS: Tosyl acetyl-adenosine was dissolved in acetonitrile, and I-131-NaI was added and heated to synthesize IAD. Female Fisher 344 rats innoculated with breast tumor cells were injected witb 0.27 MBq of IAD. Rats were sacrificed at 0.5, 1, 2, 4, 24h and the % of injected dose per gram of tissue (%ID/g) was determined. For scintigraphy, rats bearing breast cancer were administered with 1.11 MBq of IAD and imaging was perforrned after 2 and 24h. Then, rat body was fixed and rnicrotomized slice was placed on radiographic film for autoradiography, RESULTS: %ID/g of tumor wa.' 0.74 (0.5h), 0.73 (1h), 0.55 (2h), 0.38 (4h), and 0.05 (24h), respectively. At 1h after injection, %ID/g of tumor was higher than that of heart (0.34), liver (0.42), spleen (0.47), kidney (0,69), muscle (0.14), bone (0.33) and intestine (0.51). However, %1D/g of tumor was lower than blood (1.06), lung (0.77), and thyroid (177.71). At 4h, %ID/g of tumor in comparison with other tissue did not change. Tumor contrast expressed by tumor to blood ratio was 0.69 and tumor to muscle ratio was 5.11 at 1h. However, these ratios did not improve through 24h. On autoradiogram and scintigraphy at 2 and 24 hour, the tumor was well visualized. CONCLUSION: This results suggest that Ial) may have a potential for tumor scintigraphy. However, further work is needed to improve localization in tumor tissue.
Adenine ; Animals ; Autoradiography ; Breast Neoplasms* ; Breast* ; DNA ; Female ; Heart ; Hot Temperature ; Humans ; Intestines ; Kidney ; Liver ; Lung ; Radionuclide Imaging* ; Rats* ; Spleen ; Thyroid Gland ; X-Ray Film

We evaluated the efficacy of recombinant human thyroid-stimulating hormone (rhTSH) versus thyroid hormone withdrawal (THW) prior to radioiodine remnant ablation (RRA) in thyroid cancer. A systematic search of MEDLINE, EMBASE, the Cochrane Library, and SCOPUS was performed. Randomized controlled trials that compared ablation success between rhTSH and THW at 6 to 12 months following RRA were included in this study. Six trials with a total of 1,660 patients were included. When ablation success was defined as a thyroglobulin (Tg) cutoff of 1 ng/mL (risk ratio, 0.99; 95% confidence interval, 0.96-1.03) or a Tg cutoff of 1 ng/mL plus imaging modality (RR 0.97; 0.90-1.05), the results of rhTSH and THW were similar. There were no significant differences when ablation success was defined as a Tg cutoff of 2 ng/mL (RR 1.03; 0.95-1.11) or a Tg cutoff of 2 ng/mL plus imaging modality (RR 1.02; 0.95-1.09). When a negative 131I-whole body scan was used solely as the definition of ablation success, the effects of rhTSH and THW were not significantly different (RR 0.97; 0.93-1.02). Therefore, ablation success rates are comparable when RRA is prepared by either rhTSH or THW.
Catheter Ablation ; Clinical Trials as Topic ; Databases, Factual ; Humans ; Iodine Radioisotopes/*therapeutic use ; Radiopharmaceuticals/*therapeutic use ; Recombinant Proteins/biosynthesis/genetics/therapeutic use ; Risk ; Thyroglobulin/analysis/metabolism ; Thyroid Neoplasms/*drug therapy/ultrasonography ; Thyrotropin/genetics/metabolism/*therapeutic use ; Treatment Outcome ; Whole Body Imaging

PURPOSE: To compare Multi Echo Data Image Combination (MEDIC) and fast SE T2- weighted images with fat saturation (T2FS) to suggest more accurate evaluation of the histologic components of soft-tissue tumors. MATERIALS AND METHODS: The experimental group included 25 histologic tissues (5 vascular, 4 neural, 4 fibrous, 4 hypercellular, 2 hemorrhagic necroses, 2 cystic, 2 lipoid, 1 myxoid stroma, and 1 thrombus) in 10 patients who had pathologically confirmed schwannoma (n = 3), hemangioma (n = 2), lipoma (n = 1), angiokeratoma (n = 1), synovial sarcoma (n = 1), liposarcoma (n = 1), and malignant fibrous histiocytoma (n = 1). The inhomogeneity values were measured using the standard deviation value (SD) divided by the mean value as SD presents an error amount similar to that of imaging heterogeneity. RESULTS: The inhomogeneity values of 25 histologic components were lower on MEDIC than those on T2FS (p < .001). CONCLUSION: We conclude that MEDIC is more accurate than T2FS for evaluating the tissue components of soft-tissue tumors using digitalized data because MEDIC images have far lower inhomogeneity.
Angiokeratoma ; Hemangioma ; Histiocytoma, Malignant Fibrous ; Humans ; Lipoma ; Liposarcoma ; Necrosis ; Neurilemmoma ; Sarcoma, Synovial