[Three-dimensional reconstruction of heart valves]

The reconstruction of three-dimensional data sets from two-dimensional echocardiographic images offers several fundamental advantages: 1. more complete data than present in the few standard 2D-view; 2. off-line generation of any desired plane, cut, or perspective after the data set has been acquired; 3. access to quantitative parameters like surface areas (e.g., of valve leaflets or portions of leaflets), volumes, and others, without geometric assumptions. The mitral valve has been the focus of several studies using various techniques of reconstruction of transthoracic or transesophageal images. These studies have shown the mitral annulus to be a non-planar, "saddle-shaped" structure, with an average distance of highest to lowest points of 14 mm in normals. This recognition of mitral annular non-planarity has led to a more stringent echocardiographic definition of mitral valve prolapse. Further studies have shown systolic shrinkage of mitral annular area by about 30% and systolic apico-basal translation of the annulus by approximately 1 cm in normals. In patients with dilated cardiomyopathy, the annulus is flattened, and both cyclic change in annular area and apico-basal translation are significantly reduced. 3D-studies of the left ventricular outflow tract in hypertrophic obstructive cardiomyopathy allow measurement of outflow tract and leaflet surface areas and dynamic spatial visualization of systolic anterior motion of the anterior mitral leaflet. Automated techniques to reconstruct the full grey value data set from a high number of parallel or rotational transesophageal planes allow impressive visualization of normal and diseased mitral and aortic valves or valve prostheses, with special emphasis on generating "surgical" views and perspectives, which cannot be obtained by conventional tomographic imaging.(ABSTRACT TRUNCATED AT 250 WORDS)

[Investigations carried out to ascertain the dose-effect relationship of a BCG vaccine, strain 1331 Copenhagen, in neonates and young infants (author's transl)]

1405 neonates and infants were vaccinated with BCG Vaccine (strain 1331 Copenhagen) at five clinics in the Federal Republic of Germany. Doses in logarithmic increments from 22000 to 250000 VU (viable units)/0.1 ml were given by strictly intradermal injection. Carrying out the post-vaccinal tuberculin test by the MENDEL-MANTOUX technique, the dose-effect relationship could be demonstrated (Fig. 3). Conversion rates raised from 43% to 76% (Tab. 1); they are furthermore depending from the tuberculin dose and the assessment of the skin reaction. Tests with up to 50 I.U. of purified tuberculin were resulting in conversion rates over 90% for vaccination doses of 100 000 VU and more, any palpable infiltration regarding as a positive result (Fig. 4). The vaccine showed good safety in all concentrations employed concerning reactions at the site of injection. Lympnode enlargement, palable even 12 weeks postvacc., was common. In the course of the trial there was one case of suppurative lymphadenitis among the 262 children who were given the vaccine in the highest concentration (250000 VU). Subsequent trials revealed a rate of this complication in the 1:1000 range. The approval for the vaccine with 100000-300000 VU/dose has subsequently been given by the Federal Bureau for Sera and Vaccines.