Migration of paradoxic embolus through a patent foramen ovale diagnosed by echocardiography: successful thrombolysis.
Explore the source record for details and available documents.
Echocardiography↗
Biomedical subjects
M Staiger
Publications and source records attributed to M Staiger.
Selection of processing algorithms for digital image compression: a rank-order study.
RATIONALE AND OBJECTIVES: We investigated non-receiver operating characteristic (non-ROC) methods for the selection of processing algorithms for digital image compression. METHODS: We performed a multipoint, rank-order study with 20 posteroanterior chest images, each processed using four different algorithms. Seven radiologists reviewed these alongside the digitized noncompressed image. Observers were forced to rank order the similarity and/or difference of the processed images to the nonprocessed image in each case. RESULTS: A two-way analysis of variance of the rankings was statistically significant (p = .025), indicating that one processing scheme yielded images that were clearly perceived as the most similar to the nonprocessed images. The selected processing scheme was not the one that yielded the lowest quantitative difference from the nonprocessed images as measured by root mean square error. CONCLUSION: Non-ROC study designs that are highly sensitive to small differences among similar images can be used to select processing algorithms.
Algorithms↗
Computer-aided detection of clustered microcalcifications in digitized mammograms.
RATIONALE AND OBJECTIVES: We investigated a computer-aided detection (CAD) scheme for clustered microcalcifications in digitized mammograms. METHODS: A multistage CAD scheme was developed and tested. To increase sensitivity, the scheme uses a Gaussian band-pass filter and nonlinear threshold. A multistage local minimum searching routine and a multilayer topographic feature analysis are used to reduce the false-positive detection rate. One hundred ten digitized mammograms were used in this preliminary test, with 55 images containing one or two verified microcalcification clusters. RESULTS: The CAD scheme achieved 100% sensitivity and had an average false-positive detection rate of 0.18 per image. CONCLUSION: The CAD scheme performs as well as many published schemes and has some unique advantages to further improve detection sensitivity and specificity of future CAD schemes.
Breast Diseases↗
Magnetic resonance imaging detection and wire localization of an 'occult' breast cancer.
Explore the source record for details and available documents.
Aged↗
Use of a latex cover sheath for transesophageal echocardiography (TEE) instead of regular disinfection of the echoscope?
Better visualization of cardiac structures is an advantage of transesophageal echocardiography (TEE). Because of this, the transesophageal approach is an essential window in the assessment of various cardiovascular disorders. Quick consecutive access to this instrument should not be delayed by time-consuming cleansing procedures of the probe. In this study we used a sterile latex condom in routine TEE examinations as a barrier to contamination of the echoscope, observing practical use and the incidence of perforations. Defects were detected after the procedure by visual inspection and by an airtightness test. Maneuvers or situations associated with an increased likelihood of injury were checked for. In 180 studies a total of 168 patients were consecutively examined; insertion was feasible in all but one case (99.5%). We found 8 of 181 (4.4%) sheaths defective following the procedure. Visual inspection was less sensitive (only 3 of 8) for finding defects than an airtightness test (8 times). Teeth in situ and/or a bite guard are the only sharp edges during insertion and removing the probe; these seem to be the main risk factors in latex perforation. Application of a cover sheath for each examination saves approximately two-thirds of the time otherwise necessary for a cleansing bath, and easy handling of cover sheaths for TEE make them an alternative to regular disinfection in general. For reasons of safety we recommend checking each used cover sheath after examination for holes so as not to jeopardize the following patient by the possible spread of germs from contaminated probes. Not only visual inspection but also a second method, for example, an airtightness test, is mandatory.
Disinfection↗
[Tibial intramedullary nailing without open drilling].
By means on the basis of a prospective study of 33 osteosynthesis with the unreamed tibia nail (UTN) the following conclusions were found: 1. A technical simple, intramedullary solid strength bearing device in only two diameters is available, therefore costs for stock keeping are low. Systematic interlocking of the nail is necessary. Regarding the multiplicity of indication as well as the mechanical character the UTN is close to the principle of the internal fixator. 2. As a result of its solid constitution remarkable hollow cavities do not exist, so that retention of hematoma or secretions is limited (prophylaxis of infection). 3. In case of a closed nailing procedure the less rigid fracture fixation is favourable for the biology of the bone healing (fracture hematoma, less traumatic procedure without reaming of the medullary cavity, etc.). 4. The frequently observed breakage of interlocking bolts leads spontaneously to a dynamisation favourable as to time and therefore to a better bone healing process (callus formation). 5. Time intervals of bony fractures consolidation are significantly shorter compared to the exclusive osteosynthesis with the external fixator [3]. 6. The unreamed tibia nail is an implant for both primary stabilisation of closed diaphyseal fractures of the tibia with soft tissue injury and for secondary procedure/treatment for example after external fixator osteosynthesis or initial non-operative treatment. Early change of procedure seems to be of importance.
Adult↗
Correlation of caffeine elimination and Child's classification in liver cirrhosis.
Apparent pharmacokinetic parameters of caffeine elimination from the circulation were determined in 27 patients with histologically confirmed liver cirrhosis, 8 patients with miscellaneous liver disease, and 8 patients with other than liver disease. The usefullness of this quantitative test to assess the severity of liver cirrhosis was compared to the Child-Turcotte or Child-Pugh classification score as well as to the galactose elimination capacity of these patients. Using reversed-phase high pressure liquid chromatography caffeine, paraxanthine, theophylline, and theobromine were analysed in blood plasma collected before and after an oral dose of caffeine. Compared to apparent caffeine pharmacokinetics in patients with normal livers or miscellaneous liver disease, cirrhosis was characterized by a statistically significant reduction in apparent caffeine clearance and prolongation in half-life. The reduced apparent plasma disappearance rate of caffeine in cirrhotics was related to the retarded formation of paraxanthine which was the main metabolite of caffeine in blood plasma both in the absence or presence of liver disease. The apparent caffeine clearance in cirrhosis decreased with increasing Child-Turcotte classification score: Child's class A patients differed significantly from Child's class B or Child's class C patients, whereas the difference between Child's class B and C patients did not reach statistical significance (Wilcoxon's rank test). In addition there was a strong correlation between the Child-Pugh classification score and apparent caffeine clearance (P less than 0.001). However, no correlation existed between Child's classification and galactose elimination capacity. Our data emphasize the value of the Child-Turcotte or Child-Pugh classification in assessing the severity of liver cirrhosis in a simpler and less time-consuming way than using quantitative liver function tests.
Administration, Oral↗