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H Bunke

Publications and source records attributed to H Bunke.

11 recordsLinked to original sources

Restricted surface matching--numerical optimization and technical evaluation.

Accurate and reliable registration is one of the most important issues in computer-aided surgery, as small errors may have a large influence on the overall accuracy of the system. The restricted surface-matching algorithm (RSM), initially developed for periacetabular osteotomy surgery (PAO), has been improved to become numerically more stable and reliable. To assess the accuracy and sensitivity of registration, a framework is presented that evaluates two aspects of registration: the sensitivity and raw performance of the registration algorithm are tested in a stand-alone environment, and the integration into a CAS system is analyzed by evaluating the accuracy of the complete system. For the latter tests, spherical-headed titanium screws used as fiducial landmarks provide a reference transformation for the registration. This framework was used to analyze the performance of RSM for PAO surgery. The sensitivity analysis showed the algorithm to be insensitive to noise up to a magnitude of 3 mm. Both the sensitivity analysis and simulated surgical environment tests showed that an accuracy can be attained of better than 2 mm in the region of interest, and better than 4 mm far away from the region of interest. This is sufficient for safely assisting PAO surgeries.

Algorithms↗

Influence of two infant formulas and human milk on the development of the faecal flora in newborn infants.

The establishment of the faecal flora of 39 full-term infants fed exclusively on breast milk (n = 20) or with two different modern adapted cow's milk formulas (n = 19) was studied during the first 3 months of life. One formula investigated was based on 100% bovine casein as the protein source whereas the other formula contained bovine milk proteins with a whey/casein ratio of 60:40. A faecal flora rich in bifidobacteria was found in all study groups; the growth of putrefactive bacteria (especially Bacteroides spp.), however, was limited. In formula-fed infants, significantly higher bacterial counts of enterococci and clostridia were detected compared to breast milk-fed infants. Similarities and differences due to the feeding regimen were particularly reflected in the pattern of the anaerobic bacterial species. Bifidobacterium bifidum, B. infantis and B. breve constituted the majority of the bifidobacterial flora independent of the type of milk feeding. Other bifidobacterial species such as B. longum, B. adolescentis, B. parabifidum and B. pseudo-catenulatum were detected in high numbers and at low frequencies in breastfed infants. The latter three were observed in infants fed the whey/casein formula as well. It seems that infants fed a casein formula develop a faecal flora more like that of breastfed infants concerning Lactobacillus spp. (especially L. fermentum and L. brevis).

Animals↗

[Variations in the composition of breast milk in Wilson's disease].

Wilson's disease is a rare genetic disorder of copper metabolism with autosomal recessive inheritance. It occurs between the 6th and 45th year of life. An early and reliable diagnosis, if possible in the preclinical stage, is the prerequisite for starting therapy in time. By the treatment the quality of life and the expectation of life are raised considerably. If consistent treatment is given, there will be no objections to pregnancy in Wilson's disease. It should be interrupted only in case of marked portal hypertension and in the presence of oesophageal varices. The examination of the breast milk of a patient suffering from Wilson's disease showed a reduction in the trace elements copper and zinc. It may be necessary to think of copper and zinc substitution in children fed with breast milk only.

Adult↗

Left ventricular boundary detection from spatio-temporal volumetric computed tomography images.

This paper presents a new automatic technique for left ventricle boundary detection from a set of three-dimensional (3D) computed tomography (CT) volumetric cardiac images. The goals of this paper are to incorporate the temporal information into LV boundary detection, to link the shape modeling and LV boundary detection together, and to provide a compact representation of recovered LV boundaries to cardiac imaging. The proposed technique introduces spatio-temporal boundary detection and iterative model-based boundary refinement to left ventricular boundary extraction. The proposed technique has been applied to two sets of four-dimensional (4D) computed tomography images. Experimental results are compared with the manually edited images.

Algorithms↗