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M Voth

Publications and source records attributed to M Voth.

7 recordsLinked to original sources
PubMed2006

Therapeutic status of radiosynoviorthesis of the knee with yttrium [90Y] colloid in rheumatoid arthritis and related indications.

Radiosynoviorthesis (RSO) with an yttrium-90 colloid offers a local and minimally invasive therapy for treating inflammatory hypertrophy of the synovial membrane of the knee that has arisen from numerous kinds of disorder: these include rheumatoid arthritis (RA), osteoarthritis (OA), spondyloarthropathy, villonodular synovitis and others. There is substantial evidence that this treatment is efficacious and that, in view of the benefits that it offers, its tolerability and safety are very good. Administration should be restricted to patients in whom other therapies (including locally injected corticoids) have failed, and proper attention must be paid to correct administration, including post-treatment immobilization and the co-administration of corticoids, to minimize the risk of leakage and of efflux through the puncture channel.

Arthritis, Rheumatoid↗
PubMed2006

The effect of the beta-emitting yttrium-90 citrate on the dose-response of dicentric chromosomes in human lymphocytes: a basis for biological dosimetry after radiosynoviorthesis.

The production of dicentric chromosomes in human lymphocytes by beta-particles of yttrium-90 (Y-90) was studied in vitro to provide a basis of biological dosimetry after radiosynoviorthesis (RSO) of persistent synovitis by intra-articular administration of yttrium-90 citrate colloid. Since the injected colloid may leak into the lymphatic drainage exposing other parts of the body to radiation, the measurement of biological damage induced by beta-particles of Y-90 is important for the assessment of radiation risk to the patients. A linear dose-response relationship (alpha = 0.0229 +/- 0.0028 dicentric chromosomes per cell per gray) was found over the dose range of 0.2176-2.176 Gy. The absorbed doses were calculated for exposure of blood samples to Y-90 activities from 40 to 400 kBq using both Monte Carlo simulation and an analytical model. The maximum low-dose RBE, the RBE(M) which is equivalent to the ratio of the alpha coefficients of the dose-response curves, is well in line with published results obtained earlier for irradiation of blood of the same donor with heavily filtered 220 kV X-rays (3.35 mm copper), but half of the RBE(M) relative to weakly filtered 220 kV X-rays. Therefore, it can be concluded that for estimating an absorbed dose during RSO by the technique of biological dosimetry, in vitro and in vivo data for the same radiation quality are necessary.

Beta Particles↗
PubMed2006

Biological dosimetry after yttrium-90 citrate colloid radiosynoviorthesis.

UNLABELLED: Radiosynoviorthesis (RSO) with the ss-particle-emitting nuclide yttrium-90 is an established concept for the treatment of persistent synovitis of the knee joint. The AIM of this study was to investigate the biological radiation effect on the basis of a characteristic radiation parameter. PATIENTS, METHODS: After RSO procedures with yttrium-90 citrate colloid and subsequent immobilisation of the knee, blood specimens of 10 patients were collected immediately before RSO and 11 to 13 days after the intervention. The yield of dicentric chromosomes in the lymphocytes was determined exclusively in metaphases of the first cell cycle in vitro. In addition, activity leakage was measured by wholebody bremsstrahlung-scintigraphy. RESULTS: No statistically significant increase in the number of dicentric chromosomes (26 before treatment and 34 after treatment) in 20 192 cells analyzed from the 20 blood samples could be found as a result of RSO. However, the analysis of at least 1000 cells per blood sample demonstrates a tendency for a biological radiation effect in the blood of patients on the basis of this characteristic radiation parameter. Two of the 10 RSO patients had undergone a second RSO using yttrium-90 citrate, whereby one patient displayed activity transport out of the knee joint, amounting to 6 MBq. Only for him a radiation effect (about 130 mGy per single RSO) could be calculated by biological dosimetry. CONCLUSION: Since in general, based on the analysis of dicentric chromosomes in at least 1000 lymphocytes per individual, detection limits for groups of persons after long-term exposures to low-LET radiation of 50-100 mGy are possible, we assume that RSO with yttrium-90 should be associated with a low whole-body radiation exposure.

Adult↗
PubMed2004

[Mobilization of stem cells by granulocyte colony-stimulating factor for the regeneration of myocardial tissue after myocardial infarction].

BACKGROUND AND OBJECTIVE: Animal data suggest that mobilized bone marrow cells (BMC) may contribute to tissue regeneration after myocardial infarction (MI). However the safety, feasibility and efficacy of treatment with granulocyte colony-stimulating factor (G-CSF) to mobilize BMC after acute myocardial infarction in patients is unknown. We analysed cardiac function and perfusion in 5 patients who were treated with G-CSF in addition to standard therapeutical regimen. METHODS AND RESULTS: 48 h after successful recanalization and stent implantation in 5 patients with acute MI, the patients received 10 micro g/kg bodyweight/day G-CSF subcutaneously for a mean treatment duration of 7.6+/-0.5 days. Peak value of CD34 (+) cells, a multipotent subfraction of bone marrow cells, was reached after 5.0+/-0.7 days. After 3 months of follow-up global left ventricular ejection fraction (determined by radionuclid-ventriculography) increased significantly from 42.2+/-6.6 % to 51.6+/-8.3 % (P<0.05). The wall motion score and the wall perfusion score (determined by ECG gated SPECT) decreased from 13.5+/-3.6 to 9.9+/-3.5 (P<0.05) and from 9.6+/-2.9 to 7.0+/-4.5 (P<0.05), respectively, indicating a significant improvement of myocardial function and perfusion. No severe side effects of G-CSF treatment could be observed. Malignant arrhythmias were not observed either. CONCLUSION: In patients with acute MI, treatment with G-CSF to mobilize BMC appears to be well tolerable under clinical conditions. Improved cardiac function and perfusion may be attributed to BMC-associated promotion of myocardial regeneration and neovascularization.

Adult↗
PubMed2004

Impact of positron emission tomography on strategy in liver resection for primary and secondary liver tumors.

PURPOSE: Outcome of patients with metastatic disease mainly depends on accurate preoperative tumor staging. 18[F]fluorodeoxyglucose positron emission tomography (18F-PET) has been proven to be a valuable diagnostic tool in a number of different tumors but its direct influence on liver surgery has not been thoroughly investigated. MATERIALS AND METHODS: Between July 1999 and March 2000, 50 consecutive patients with 174 suspected liver lesions were admitted to the University Hospital Jena. All 50 patients underwent abdominal ultrasound, CT-scan, and 18-FDG positron emission tomography scanning. In 23 patients the diagnostic work-up was completed by MRI scan. RESULTS: Altogether there were a total of 174 histologically proven intrahepatic lesions, nine of which were benign. The sensitivity, specificity, and positive predictive value of PET for all hepatic lesions was 82%, 25%, and 96% compared with 63%, 50%, and 96% for abdominal ultrasound, 71%, 50%, and 97% for CT-scan, and 83%, 57%, and 97% for MRI-scan. In 23 of 50 patients 24 extrahepatic lesions were identified. In these patients the sensitivity and specificity of PET-compared to abdominal ultrasound, CT-scan, and MRI-scan for all extrahepatic lesions-was 63% and 60%, 29% and 25%, 47% and 50% and 40% and 50%, respectively. The findings on PET scan had a direct impact on operative management in nine patients (18%). CONCLUSIONS: Our series demonstrates good sensitivity and specificity for the detection of primary and secondary liver lesions which is superior to ultrasound and CT scan but not to MRI scan. The main value of PET scan consists in the detection of extrahepatic tumor (64%). Due to better detection of extrahepatic tumor, FDG-PET is a very useful addition to the currently used anatomically-based images in all cases of advanced tumor spread with high risk of extrahepatic tumor.

Adenoma, Liver Cell↗
PubMed2003

[The value of fluorodeoxyglucose positron emission tomography (FDG-PET) in differentiation of pancreatic lesions].

Fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) is a functional imaging modality that is based on the metabolic activity which is higher in most malignant tumors than benign tissues. This short review describes the basics of FDG-PET and gives a discussion of its role in differentiation of focal pancreatic lesions. The diagnostic accuracy in patients with active inflammation or cancer of the pancreas can be improved by dynamic acquisition of focal pancreatic lesions.

Cholangiopancreatography, Endoscopic Retrograde↗