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21.
Annemieke C. Kole MD Omgo E. Nieweg MD PhD Robert J. van Ginkel MD Jan Pruim MD PhD Harald J. Hoekstra MD PhD Anne M. J. Paans PhD Willem Vaalburg PhD Dr. Heimen Schraffordt Koops MD PhD 《Annals of surgical oncology》1997,4(1):57-63
Background: It is often difficult to detect a local recurrence of soft-tissue sarcomas due to disturbance of the normal anatomy by previous
surgery and radiotherapy. The aim of this study was to assess the value of positron emission tomography (PET) with [18F]fluoro-2-deoxy-d-glucose (FDG) for detecting local recurrences.
Methods: In the period 1992–1995, 17 patients with proven or suspected local recurrence of soft-tissue sarcoma were examined using
FDG-PET. Fifteen of these patients were ultimately proven to have a recurrence.
Results: Recurrence was visualized in 14 patients (93%). Small tumors (maximum diameter 0.5 cm) were as easily visible as large lesions
(maximum diameter 20 cm). In one patient the PET scan was positive, but the recurrence could not be proven histologically.
Recurrence was proven 1 year later. A recurrent low-grade liposarcoma was not visualized. The two patients with benign lesions
had a negative PET scan. The mean glucose metabolic rate was calculated to be 13.2 μmol/100 g/min (range 1.9–28.4). A correlation
was found between the histological malignancy grade and the metabolic rate (p<0.05; Kruskal-Wallis).
Conclusion: PET with FDG is a useful addition to the diagnostic armamentarium for detecting local recurrence of soft-tissue sarcomas
and provides an indication of the malignancy grade of the recurrent lesion.
Presented at the 47th Annual Meeting of The Society for Surgical Oncology, Houston, Texas, March 17–20, 1994. 相似文献
22.
Harald Fricke Eva Fricke Reiner Weise Annett Kammeier Oliver Lindner Wolfgang Burchert 《Journal of nuclear medicine》2004,45(10):1619-1625
Nonuniform soft-tissue attenuation affects the diagnostic accuracy of SPECT in myocardial perfusion imaging. The attenuation map required for attenuation correction can be acquired using x-ray tomography (CT). Frequent findings in attenuation-corrected images are defects in the apical and anterior myocardial wall. We assume that these are artifacts produced by misalignment of SPECT images and the attenuation map. METHODS: One hundred forty patients underwent myocardial perfusion imaging with 99mTc-methoxyisobutylisonitrile. Twenty-seven of 140 showed pronounced defects in the apical or anterior wall only after CT-based attenuation correction. SPECT and corresponding CT slices were examined for misalignment in the ventrodorsal direction (y-direction) visually and by threshold-based delineation of the body surface. Mismatched studies were realigned and image reconstruction and analysis were redone. The effect of the correction was assessed visually and by semiquantitative analysis based on a 20-segment model using 4D-MSPECT. RESULTS: In 15 of 27 patients, the improved coregistration led to smaller and less-pronounced defects in the regions mentioned. In 6 of 27 patients, former defects were judged as normal. No improvement was seen in only 4 patients. In these 4 subjects, the mismatch in the y-direction was <1 pixel (7 mm), and visual inspection suggested a coincident mismatch in the craniocaudal direction. In 2 cases, coregistration was not possible because the body outline extended beyond the CT field of view. Semiquantitative analysis revealed a significant increase of the relative uptake in the apex; in the apical segments of the anterior, septal, and inferior wall; and in the mid-anterior and mid-anteroseptal segment. Basal segments of the anterolateral, lateral, and inferolateral wall and the middle inferolateral segment showed a significant decrease of relative uptake. CONCLUSION: Misalignment in the y-direction between SPECT and the attenuation map can lead to artifacts in the apical, septal, and anterior wall, which will appear as defects. It also can cause overcorrection in the basal inferior and lateral segments. There is evidence that mismatches along the other directions may have a similar effect. The coregistration of SPECT and the attenuation map needs to be verified for every patient, even when using integrated dual-modality imaging devices. 相似文献
23.
The metabolism of nomifensine was studied after single oral and intravenous administration and after 2 weeks of oral dosing. The three principal metabolites reached maximum plasma concentrations rapidly (in 1 to 1.5 hours) after nomifensine administration. Less than 10% was detected as a free, unconjugated form. All three metabolites were eliminated rapidly (elimination t1/2 values between 6.8 and 9.0 hours). Only very low concentrations of free metabolites were found in plasma after 24 hours of nomifensine administration. AUC values for free metabolites were between 0.27 to 0.46 hr X mumol/L after all nomifensine schedules. Two weeks of dosing had no significant influence on the elimination t1/2 or AUC values of the metabolites, indicating no change in the hydroxylation and methylation reactions. In addition, there were no changes in the conjugation reactions during prolonged nomifensine dosing. Nomifensine has a very short t1/2 and no tendency for accumulation after repeated doses. We conclude that nomifensine's clinical pharmacokinetic profile is not significantly changed by the kinetic behavior of its three main metabolites after the usual maintenance doses. 相似文献
24.
25.
Markus Dietlein Klemens Scheidhauer Eberhard Voth Peter Theissen Harald Schicha 《European journal of nuclear medicine and molecular imaging》1997,24(11):1342-1348
Metastases of differentiated thyroid cancer may show different uptake patterns for fluorine-18 fluorodeoxyglucose and [131I]NaI. FDG positron emission tomography (PET), iodine-131 whole-body scintigraphy (131I WBS) and magnetic resonance imaging were performed in 58 unselected patients, and spiral computed tomography (CT) of the
lung in 25 patients. Thirty-eight patients presented with papillary carcinomas, 15 patients with follicular carcinomas and
five patients with variants of follicular carcinoma. Primary tumour stage (pT) was pT1 in 3, pT2 in 19, pT3 in 11 and pT4
in 25 cases. For the detection of metastases, FDG PET was found to have a sensitivity of 50%, 131I WBS a sensitivity of 61%, and the two methods combined a sensitivity of 86%. When FDG PET was limited to patients with elevated
thyroglobulin (Tg) levels and negative 131I WBS, the sensitivity of this algorithm was 82%. Of the 21 patients with lymph node metastases, seven presented with FDG
uptake but no iodine uptake. In four of them, a second FDG hot spot appeared in a lymph node metastasis of normal size. Five
of the seven patients underwent surgery. None of the eight patients with pulmonary metastases smaller than 1 cm exhibited
FDG uptake, while five of them had iodine uptake. All had positive results on spiral CT. In conclusion, FDG PET cannot be
substituted for 131I WBS. If the Tg level is elevated and 131I WBS is negative, FDG PET can be used to detect lymph node metastases and complements anatomical imaging. A spiral CT of
the lung is useful to exclude pulmonary metastases before planning a dissection of iodine-negative lymph node metastases.
Received 2 May and in revised form 8 July 1997 相似文献
26.
C G Lindberg H Henrikson E Lindstedt C Lundstedt H Stridbeck 《Acta radiologica (Stockholm, Sweden : 1987)》1992,33(1):50-52
Mechanical lithotripsy of urinary bladder stones was performed with the RotoLith lithotriptor in 8 pigs with implanted human stones or artificial stones after open cystotomy. The effect of the treatment on the urinary bladder was investigated macro- and microscopically immediately after the lithotripsy in 4 animals and 4 weeks after the lithotripsy in the other 4 animals. The stones were fragmented into very small pieces which would have been possible to pass with the urine. The histopathologic examination immediately after the procedure showed slight mucosal edema, patches of erosions in the mucosa, and minor submucosal bleeding. Microscopic examination of the bladders removed 4 weeks after lithotripsy showed slight chronic inflammation. The experimental results have encouraged us to plan to use this lithotripsy procedure in selected patients with bladder stones. 相似文献
27.
Munzel Peter; Bock-Hennig Barbara; Schieback Sylvia; Gschaidmeier Harald; Beck-Gschaidmeier Simone; Bock Karl Walter 《Carcinogenesis》1996,17(2):197-202
Modulation of DNA synthesis by 2,3,7,8-tetrachlorodi-benzo-p-dioxin(TCDD) was studied in primary cultures of hepatocytes and inrat liver epithelial cells (WB-F344) to develop models for studieson the interactions between the activated Ah receptor and cellulargrowth control. In hepatocytes TCDD either positively or negativelymodulated EGF-stimulated DNA synthesis. In the presence of ethlnylestradiol1012 M TCDD moderately increased EGF-stimulated DNA synthyesis( 相似文献
28.
29.
J Aksnes K Nordstrand H Lindberg O Christensen K Vatne O Smiseth T Fr?ysaker 《Scandinavian journal of thoracic and cardiovascular surgery》1992,26(1):57-59
In 28 patients with the left internal mammary artery (IMA) used as a sequential coronary artery graft, clinical and angiographic evaluation was made 19-47 months postoperatively. Patency was 96% in the proximal anastomoses and 93% in all the anastomoses. Angiography, however, showed optimal function in only 75% of the distal graft ends. These observations indicate that routine use of left IMA as a sequential graft should be restricted to experienced surgeons. Clinical and angiographic findings did not always correlate, emphasizing that evaluation of IMA-graft patency should include angiography. 相似文献
30.
Harald Schrem Moritz Kleine Jürgen Borlak Jürgen Klempnauer 《Liver transplantation》2006,12(12):1832-1840
In fulminant hepatic failure, the use of bioartificial liver support (BAL) with porcine hepatocytes is the subject of a current and controversial debate.1 Specifically, the issue of cross-species physiological incompatibilities has not been addressed so far. We therefore investigated the effects of species-specific cytokines in single and cocultures on hepatocyte function. Hepatocyte cultures were isolated from human resection specimens and from Landrace pigs. Single and cocultures were exposed to porcine and human interleukin (IL)-6 or tumor necrosis factor (TNF)-alpha. Changes in expression of C-reactive protein (CRP), albumin, CCAAT enhancer binding protein (C/EBP)-alpha and C/EBP-beta and metabolic competence of cultured cells was studied by measuring testosterone metabolite production. After human or porcine IL-6 dosing, CRP was induced up to 100-fold in human hepatocyte cultures, while porcine hepatocytes responded marginally (2- to 5-fold). Treatment with human or porcine IL-6 or TNF-alpha resulted in reduced albumin production, albeit at different levels when human and porcine hepatocytes were compared (P = 0.001). Unlike human, porcine hepatocytes produced less of 6alpha-hydroxytestosterone (6alpha-HT) (P < 0.001) and 7alpha-HT (P < 0.001) after human or porcine IL-6 dosing and treatment with species-specific TNF-alpha induced (human hepatocytes) or decreased (porcine hepatocytes) 6beta-HT production (P = 0.021). In coculture with free exchange of metabolites, porcine hepatocytes produced less 6alpha-HT (P = 0.048) and 16alpha-HT (P = 0.033), whereas after treatment with human IL-6 reduced CRP gene and protein expression was observed with human hepatocytes (P = 0.013). In conclusion, species-specific responses of hepatocytes to cytokines and interactions with xenobiotic metabolites may limit the clinical effectiveness of porcine hepatocytes in BAL. 相似文献