Search results for "nuclear medicine"
showing 10 items of 3573 documents
Reversible effect of magnetic fields on human lymphocyte activation patterns: different sensitivity of naive and memory lymphocyte subsets.
2009
The aim of this study was to investigate the influence of 50 Hz magnetic or static magnetic fields of 0.5 mT on subsets of human CD4(+) T cells in terms of cytokine release/content, cell proliferation and intracellular free calcium concentration. CD4(+) T cells can be divided into different subsets on the basis of surface marker expression, such as CD45, and T cells can be divided into naive (CD45RA(+)) and memory (CD45RA(-)) cells. In this study, the effects of magnetic fields after 24 and 48 h of cell culture were analyzed. We found that the CD4(+)CD45RA(-) T subset were more sensitive after 2 h of exposure. Decreases in the release/content of IFN-gamma, in cell proliferation and in intra…
Relapse Analysis of Irradiated Patients Within the HD15 Trial of the German Hodgkin Study Group
2015
Purpose To determine, in the setting of advanced-stage of Hodgkin lymphoma (HL), whether relapses occur in the irradiated planning target volume and whether the definition of local radiation therapy (RT) used by the German Hodgkin Study Group (GHSG) is adequate, because there is no harmonization of field and volume definitions among the large cooperative groups in the treatment of advanced-stage HL. Methods and Materials All patients with residual disease of ≥2.5 cm after multiagent chemotherapy (CTX) were evaluated using additional positron emission tomography (PET), and those with a PET-positive result were irradiated with 30 Gy to the site of residual disease. We re-evaluated all sites o…
Omitting axillary lymph node dissection after positive sentinel lymph node in the post-Z0011 era: Compliance with NCCN and ASCO clinical guidelines a…
2021
Summary Purpose In the ACOSOG Z0011 trial, patients with primary breast cancer and 1–2 tumor-involved sentinel lymph nodes (SLNs) undergoing breast-conserving surgery had no oncological outcome benefit after axillary lymph node dissection (ALND), despite a relevant rate of non-SLN metastases of 27%. According to the St Gallen expert consensus, and NCCN and ASCO clinical guidelines, ALND may be avoided in patients who meet all ACOSOG Z0011 inclusion criteria. This recommendation can also be extended to patients undergoing mastectomy, with 1 or 2 positive SLNs and an indication for chest wall radiation, in whom axillary radiotherapy can be proposed as an alternative to completion ALND. The ai…
Inflammatory Pseudotumor of Mediastinum Treated with Tomotherapy and Monitored with FDG-PET/CT: Case Report and Literature Review
2010
Mediastinal inflammatory pseudotumor is a rare disease with reactive pseudoneoplastic features and a proven capacity for local invasion. The radiographic appearance of inflammatory pseudotumor is quite non-specific and the definitive diagnosis is based on the histological evaluation of tissue specimens. Resection of the lesion is the treatment of choice. However, nonsurgical treatments such as radiotherapy and steroids have been employed in the setting of incomplete surgical resection, tumor recurrence, and patients being unfit for surgery. The case described here is being reported because of the rare mediastinal location and atypical treatment approach including salvage irradiation and mon…
A new method for the placement of brachytherapy probes in paranasal sinus and nasopharynx neoplasms
1999
Abstract Purpose: In afterloading therapy, the exact placement of the applicator is crucial for the result of radiotherapy. A deviation of few millimeters from the target leads to a significant reduction of radiation energy to the tumor. Methods and Materials: We present a new method using a computer-assisted device for three-dimensional placing of afterloading probes based on CT scans that allows for the exact placement. Results: Target points have been reached with an accuracy of 0.6 mm. Since 1991 we have used this technique for 24 clinical applications in 11 patients with recurrent neoplasms in the region of the paranasal sinuses and nasopharynx for palliative treatment. Conclusions: Th…
Primary Orbital Liposarcoma in Li-Fraumeni Cancer Family Syndrome: A Case Report
2005
Aims and background The aim of this study was to describe a case of primary orbital liposarcoma in Li-Fraumeni syndrome. Methods and study design In July 1998 a 20-year-old woman with a histological diagnosis of orbital myxoid liposarcoma underwent surgical treatment in our department. Since the patient's family pedigree met the clinical criteria for the diagnosis of LFS, molecular analysis was performed, which resulted in a molecular profile consistent with Li-Fraumeni syndrome. Results The patient underwent orbital exenteration extended to the upper eyelid; surgical reconstructive steps were performed to permit placement of an orbital prosthesis. Two years after primary surgery the patien…
RCBF-quantification with 99mTc-HMPAO-SPECT: theory and first results.
1989
The activity concentrations of 99mTc-HMPAO in brain after intravenous injection were evaluated in 25 patients using SPECT. With additional first pass studies of heart and brain with the short lived isotope 195mAu, the cardiac output and the mean cerebral transit times of the patients were measured a short time before the HMPAO injection. The time dependence of 99mTc-HMPAO activity in the brain was registered during the first 5 min after injection over both hemispheres. Using a simplified three compartment model it was possible to calculate the mean retention fraction of HMPAO in brain from the time activity curves. It could be shown that the regional cerebral blood flow in ml/min per 100 g …
Reproducibility of imaging human knee cartilage by delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) at 1.5 Tesla
2009
Summary Objective The purpose of this study was to investigate the day-to-day reproducibility of the delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) measurement at different knee joint surfaces in healthy subjects at 1.5 Tesla (T). Methods The dGEMRIC experiment was repeated for 10 asymptomatic volunteers three times with an average interval of 5 days between scans. The measurement was performed from a single sagittal slice through the center of the lateral femoral condyle and from the center of the patella in the axial plane. Cartilage was manually segmented into superficial, deep and full-thickness regions of interests (ROIs) at different topographical locations of the femur, tibia…
Assessment of normal patellar cartilage volume and thickness using MRI: an analysis of currently available pulse sequences.
1996
Objective. The objective of this study was to analyse the potential of magnetic resonance imaging for valid determination of patellar cartilage thickness, comparing currently available pulse sequences. Design. In six patients and one cadaver the cartilage was repetitively imaged employing three spin-echo and six three-dimensional gradient-echo sequences. In the cadaveric specimen the total volume and the regional distribution of cartilage thickness were assessed and compared with the values obtained from anatomical sections by image analysis. Results and conclusions. The FLASH and fat-suppressed FLASH sequences allowed the most accurate determination of the cartilage volume and thickness. F…
Facilitating cartilage volume measurement using MRI.
2010
To compare quantitative cartilage volume measurement (CVM) using different slice thicknesses.Ten knees were scanned with a 1.5T MRI (Sonata, Siemens, Erlangen, Germany) using a 3D gradient echo sequence (FLASH, fast low-angle shot). Cartilage volume of the medial and lateral tibial plateau was measured by two independent readers in 1.5mm, 3.0mm and 5.0mm slices using the Argus software application. Accuracy and time effectiveness served as control parameters.Determining cartilage volume, time for calculation diminished for the lateral tibial plateau from 384.6+/-127.7s and 379.1+/-117.6s to 214.9+/-109.9s and 213.9+/-102.2s to 122.1+/-60.1s and 126.8+/-56.2s and for the medial tibial platea…