Biomedical subjects

U von Jan

Publications and source records attributed to U von Jan.

6 recordsLinked to original sources

PubMed2002

Interactive PC-based volume rendering of CT datasets.

In radiology, the reading of large CT volumes is a time consuming task. Interactive volume rendering (iVRT) is a promising new technique. Using dedicated hardware (VP1000, Terarecon Inc.) it can now be realized on a standard PC in a cost effective manner. For this purpose, a program built using the Visualization Toolkit with integrated functionality for the VP 1000 is used for almost real-time iVRT (8-9 frames/second). It is possible to embed opaque and translucent polygon surfaces (e.g., segmented structures). By interactively varying the opacity, color and gradient transfer functions as well as using freely placable cutting planes, the visualization can easily be adapted to different diagnostic needs.

Humans↗

PubMed2000

Telemedicine of the future: teleneuropathology.

The chief relevance of telemedicine lies in its capability to link medical practitioners and remote hospitals to larger or specialized facilities in a very fast electronic manner. This may become even more important due to current increase in subspecialization and demand for more precise diagnosis and consultation in difficult cases. A network attaching small clinics or laboratories to larger and more specialized units, and to highly specialized referral centers may improve the professional standard of health care services and education. For a wider use, a technological standardization will be required, since the existence of several types of computer and numerous image manipulation programs, have resulted in a proliferation of file formats. However, every potential user or client of telemedicine should keep in mind, that standardization also includes legal and ethical issues such as patient confidentiality and malpractice avoidance. The adoption of workable guidelines and protocols is required. Telepathology in general and teleneuropathology in particular is the practice of pathology at a distance, viewing digitized images of histological slides on a video monitor rather than directly through a light microscope. For the transmission of the digitized images from a telemicroscope to the remote diagnostic video monitor, different technologies such as ordinary telephone lines, broadband telecommunications channels, and the Internet can be used. The transmitted images may serve for primary neuropathological diagnosis, teleconsultation, quality assurance, proficiency testing, and distance learning. Static-imaging and dynamic-imaging are the two major competing technologies of telemicroscopy. Static-imaging systems appear to have levels of diagnostic accuracy which are not satisfactory for diagnostic neuropathology. On the contrary, high levels of diagnostic accuracy can be achieved using dynamic-imaging systems with the transmission of live video images in real time and by using a robotized telemicroscope with the possibility to examine the entire histological specimen under control of the remote teleneuropathologist.

Diagnostic Techniques, Neurological↗

PubMed2000

3-D visualization of the newborn's hip joint using ultrasound and automatic image segmentation.

Graf's method has been established as a standardized procedure for the diagnostic screening of developmental dysplasia of the hip in newborns. In this procedure, a two dimensional ultrasound image that has to contain standardized landmarks is taken and evaluated interactively to calculate congruence indicators. Since these indicators are only derived from a 2-D scan, they do not reflect the spatial joint structure. In our study, we visualized three dimensional scans of newborns' hip joints that were obtained using a conventional ultrasound transducer and a commercial localizer system that was fixed to the scanhead. The landmarks were detected by automatic image segmentation to avoid examiner dependent findings. The landmark structures as well as an automatically determined virtual sphere approximating the femoral head were visualized color coded on a computer screen. This kind of visualization was found to be intuitive. The evaluation of the entire joint geometry and the 3-D relations between the acetabulum and the femoral head improves the reliability of the diagnostics.

Acetabulum↗

PubMed2000

Multimedia-based courseware in the Virtual Learning Center at the Hannover Medical School.

The commercial use of the World Wide Web causes an extensive change in information technology. Web browser are becoming the universal front-end for all kinds of client-server applications. The possibilities of telematics offer a base for multimedia applications, for instance telelearning. Learning is not limited by geography and does not cause pressure of time by the user. The development of such multimedia information and communication systems demands cooperative working teams of authors, who are able to master several areas of medical knowledge as well as the presentation of these using different multimedia facilities. A very important part of graphic design in the context of multimedia applications is the creation and interactive use of images (still, moving). The growth and the complexity of medical knowledge as well as the need for continuous, fast, and economically feasible maintenance impose requirements on the media used for medical education and training. Web-based courseware in the Virtual Learning Center at the Hannover Medical School is an innovative education resource for medical students and professionals.

Computer-Assisted Instruction↗

PubMed1999

The interactive use of networking multimedia--innovative education resource for professionals and patients.

The combination of new and rapidly developing interactive multimedia computers and applications with electronic networks will require a restructuring of our traditional approach to strategic planning and organizational structure. Worldwide telecommunication networks (using satellites, cable) are now facilitating the global pooling of healthcare information and medical knowledge independent of location. The development of multimedia information and communication systems demands cooperative working teams of authors, who are able to master several areas of medical knowledge as well as the presentation of these in different multimedia forms. The assemblage of telematics and services offers a base for multimedia applications, for example teleteaching, telelearning, telepublishing, teleconsulting, teleconferencing, telemedicine etc. The expansion of the internet will also lead to the formation of interdisciplinary "Global Education Networks". The theory and practice of education are undergoing dramatic changes. Lifelong learning and adaptation of medical practice to new knowledge and new techniques will be even more important in the future.

Computer-Assisted Instruction↗

PubMed1997

[New approaches to 3D-ultrasonographic imaging of infant hips].

Ultrasound of the infant hip is an established method in the diagnosis and monitoring of the treatment of congenital dysplasia of the hip (CDH). Its use as a screening method for CDH, early diagnosis and start of therapy results in a high success rate and reduces the length of the therapy. According to Graf's technique, the examination findings are taken from a standard plane. Assessment of the examined hip joint is based on information obtained from this standard intersection plane, which has to be representative for the whole joint configuration. Furthermore, the method according to Graf requires a very expert examiner. We report on a new approach to three dimensional ultrasound of the infant hip for covering and demonstrating the complete dimensions of CDH. A maturity disorder of the infant hip located outside the standard plane should be recognized by 3D ultrasound. In contrast to already existing 3D ultrasound systems with specially constructed transducers, we use a position sensor which, in conjunction with a video tape recorder, an external computer and the corresponding software, is able to support normal ultrasound equipment. A common 7.5 or 5 Mhz linear transducer can be used. During the examination, the form and size of the femoral head is automatically analysed. The result is placed as a virtual sphere into the 3D data set. The quality of the examination should be independent of the examiner's skill.

Hip Dislocation, Congenital↗