Accurate knowledge of lymphatic drainage facilitates planning of surgery for patients with squamous cell carcinoma of the head and neck. The aim of this study was to evaluate the feasibility of a new ...injection technique for lymph node detection in patients with squamous cell carcinoma of the hypopharynx and larynx, in whom simple peritumoural injection is hampered by the tumour localisation. Computed tomography (CT)-guided lymphoscintigraphy was performed in a total of 13 patients with squamous cell carcinoma of the hypopharynx and larynx who could not be injected by simple visual inspection. In a first step, contrast medium-enhanced axial 5-mm-thick CT slices of the neck were obtained. After tumour localisation on these CT images, 1-2 ml contrast medium and, in the event of appropriate distribution, subsequently 50 MBq technetium-99m colloid were injected at one to three peritumoural sites under CT guidance. Peritumoural tracer distribution was controlled by thin-slice CT. Subsequently, planar scintigrams from anterior, right and left lateral views were obtained. In all patients, peritumoural colloid application was feasible, as shown on control CT scans. Post injection, neither severe nor minor complications were noted. The patients complained of only low pain sensations with an average score of 1.8 on a pain scale from 0 to 10. Lymphatic drainage was identified in nine of the 13 patients, with a total of 14 detected lymph nodes. In six patients, ipsilateral sentinel lymph nodes were visualised; bilateral sentinel lymph nodes were identified in one patient and contralateral lymphatic drainage was observed in two patients. CT-guided lymphoscintigraphy is a feasible and minimally invasive diagnostic tool for sentinel lymph node detection in patients with squamous cell carcinoma of the hypopharynx and the larynx. In contrast to endoscopic colloid injection under general anaesthesia, this technique seems to be a well-tolerated method for lymphatic mapping prior to surgical procedures.
This book constitutes the refereed proceedings of the 5th European Dependable Computing Conference, EDCC 2005, held in Budapest, Hungary in April 2005.
The 21 revised full papers, 5 revised practical ...experience reports, and 4 prototype description papers presented together with the abstract of a keynote and 2 fast-track papers were carefully reviewed and selected from 90 submissions. The papers are organized in topical sections on distributed algorithms, fault-tolerant design and procotols, practical experience reports and tools, assessment and analysis, measurement, hardware verification, dependable networking, and reliability engineering and testing.
Dynamic contrast-enhanced MRI is now established as the methodology of choice for the assessment of tumor microcirculation in vivo. This is assisting clinical practitioners in the management of ...patients with solid tumors and is finding prominence in the assessment of tumor treatments, including anti-angiogenics, chemotherapy, and radiotherapy. In this book, targeted at both clinical practitioners and basic scientists, the principles of the methods, their practical implementation, and their application to specific tumor types are discussed by the leading authorities in the field today. The book will serve as an invaluable single-volume reference covering all the latest developments in contrast-enhanced oncological MRI.
Conventional planar ventilation/perfusion (V/P)-imaging in those patients suspected of suffering from pulmonary thromboembolism (PTE) is of limited diagnostic value. It is the purpose of this ...retrospective study to determine whether the use of V/P-SPECT using Technegas might reduce the rate of those diagnostic uncertainties and might lead to better results.
991 patients (660 female, 331 male, age 18-90, mean 60), referred to our laboratory with suspected PTE, were examined as follows: patients inhaled 37 MBq of Technegas in the supine position and a SPECT-acquisition was started. Following SPECT-completion, 185 MBq 99mTc-MAA was injected intravenously. SPECT was then repeated. Coronal and transverse ventilation and perfusion SPECT-slices were reconstructed and compared section by section. 85 patients underwent control scans by the same technique at a mean interval of 22 months after the original scans.
As the SPECT images in almost all cases made a clear match/mismatch decision possible, we categorized all patients as embolic (PTE+) if there was at least one mismatching defect, and as non embolic (PTE-) if there were none. Our results were: PTE+: 178 patients (18%), PTE-: 808 patients (81%), uncertain: 5 patients (0.5%), if 34 triple-match defects are included: 39 patients (3.9%). 46 patients, categorized as PTE+ underwent a control V/P scan after anticoagulant therapy. In 44 of these patients, PTE was confirmed by the controls. In a control group of 39 PTE- patients, control scans were unchanged in 38 cases. From these observations we can calculate a sensitivity of 96% and a specificity of 97%.
We conclude that V/P imaging can be improved significantly by V/P SPECT using Technegas.
The results of investigating the influence of the time constant of acceleration signal transformation or vibration speed into a displacement signal are given. Regularities of displacement signal ...amplitude change after transformation of acceleration and speed signals have been determined. It is shown that the error of displacement signal amplitude change depends on the transformation time constant for the intended frequency of the input signal. Thus, its minimum value corresponds to the value of the transformation time constant, equal to half an input signal period. The results of displacement measurements obtained by using vibration speed sensors and the results of their comparison with data, obtained by employing the displacement master sensor, are given.
Alzheimer's disease (AD) and frontal lobe dementia (FLD) show characteristic patterns of regional cerebral blood flow (rCBF). However, these patterns may overlap with those observed in the aging ...brain in elderly normal individuals. The aim of this study was to develop a new method for better classification and recognition of AD and FLD cases as compared with normal controls. Forty-six patients with AD, 7 patients with FLD and 34 normal controls (CTR) were included in the study. rCBF was assessed by technetium-99m hexamethylpropylene amine oxime and a three-headed single-photon emission tomography (SPET) camera. A brain atlas was used to define volumes of interest (VOIs) corresponding to the brain lobes. In addition to conventional image processing methods, based on count density/voxel, the new approach also analysed other intrinsic properties of the data by means of gradient computation steps. Hereby, five factors were assessed and tested separately: the mean count density/voxel and its histogram, the mean gradient and its histogram, and the gradient angle co-occurrence matrix. A feature vector concatenating single features was also created and tested. Preliminary feature discrimination was performed using a two-sided t-test and a K-means clustering was then used to classify the image sets into categories. Finally, five-dimensional co-occurrence matrices combining the different intrinsic properties were computed for each VOI, and their ability to recognise the group to which each individual scan belonged was investigated. For correct classification of the AD-CTR groups, the gradient histogram in the parieto-temporal lobes was the most useful single feature (accuracy 91%). FLD and CTR were better classified by the count density/voxel histogram (frontal and occipital lobes) and by the mean gradient (frontal, temporal and parietal lobes, accuracy 98%). For AD and FLD the count density/voxel histogram in the frontal, parietal and occipital lobes classified the groups with the highest accuracy (85%). The concatenated joint feature correctly classified 96% of the AD-CTR, 98% of the FLD-CTR and 94% of the AD-FLD cases. 5D co-occurrence matrices correctly recognised 98% of the AD-CTR cases, 100% of the FLD-CTR cases and 98% of the AD-FLD cases. The proposed approach classified and diagnosed AD and FLD patients with higher accuracy than conventional analytical methods used for rCBF-SPET. This was achieved by extracting from the SPET data the intrinsic information content in each of the selected VOIs.
Relevance and diagnostics of cryoproteins Nebe, Carl Thomas; Stamminger, Gudrun; Baum, Hannsjörg ...
Laboratoriumsmedizin,
6/2015, Letnik:
38, Številka:
5
Journal Article
Odprti dostop
Cryoproteins still remain largely undiagnosed despite their clinical relevance. Cryoglobulins, cryofibrinogen and cold agglutinins respectively show a significant association with autoimmune diseases ...and non-Hodgkin’s lymphoma. The analytical part is relatively straightforward; however, the preanalytical phase is a challenge. This article briefly summarizes the relevant aspects to improve this situation.
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