Biomedical subjects

C Zeiler

Publications and source records attributed to C Zeiler.

8 recordsLinked to original sources

PubMed2001

Spatial pattern learning in rats: control by an iterative pattern.

Rats searched in a matrix of vertical poles for food hidden on top of the poles. The only information available about the location of the food was the consistent spatial pattern of the baited poles, which was a checkerboard. This spatial pattern of hidden-food locations came to control the choices of poles made by the rats. The experiments ruled out the possibility that this control can be explained by the acquisition of simple response tendencies to move from pole to pole. Instead, this behavioral control of choices was attributed to the development of a representation of the checkerboard pattern of baited locations. Spatial pattern learning may have mechanisms in common with other forms of pattern learning.

Animals↗

PubMed1999

[Fully implantable intramedullary distraction nail in shortening deformity and bone defects. Spectrum of indications].

Since the first clinical experiences with the fully implantable programmable distraction nail nearly ten years ago, the system has been improved in Munich and meanwhile used in 26 patients. During the first 10 cases there has been highest interest in the reliability of the system, while in the following the expansion of indications was more important. At the thigh a good indication beside shortening is the combination of shortening and axis deviation, even if the center of deviation is located near to the knee joint in the supracondylar area. According to preoperative planing the deformity correction can be done acutely while the lengthening procedure follows postoperatively automatically at night-time. If the stabilization with an intramedullary nail is possible, large bone defects can be treated by bone transport using this system also. The fully implantable intramedullary nail has proved its variable functions in cases of large bone defects combined with shortening of the femur. The system is able to perform the bone transport at first and the lengthening procedure automatically without any further operation thereafter.

Accidental Falls↗

PubMed1998

[Indications and technique of bone cutting].

For cutting bones different tools and techniques are available. The question which method is most advantageous depends on the basic surgical concept, the location of the bone cut and the choice of the subsequent implant. The biological activity of the anatomical site of the cut determines how much the tissue needs to be protected, taking into consideration the vascularity of the bone and avoiding heat transfer. The surgical approach depends on the implant and should be used also for the bone cut. Specific indications are given for the oscillating saw, the Gigli saw, the osteotome, drill holes and the medullary saw.

Equipment Design↗

PubMed1997

[Possibilities of osteotomy. Osteotomy and corticotomy techniques].

Corrective measures on the bone undertaken after the fusion of epiphyses are only possible through an initial break in its continuity. This paper deals with the different methods of osteotomy available to the orthopaedic or trauma surgeon. After introducing the terminology of the so-called "osteotomy", the vascularity of the bone, special features of the various osteotomy site, the different indications, and particular details of the operative procedures are discussed. Special emphasis is placed on minimally invasive techniques and osteotomies in the framework of callus distraction. In addition to established procedures a new sawing technique for the Küntscher's closed osteotomy is described.

Bone Lengthening↗

PubMed1997

[Instrumental diagnosis for therapy decision making--what is possible and desirable, what is essential and what is superfluous?].

With knowledge of the classical radiological characteristics of benign and malignant bone tumors, taking age and localization of lesion into consideration, and with the help of classification according to Lodwick, 90% of all cases can be diagnosed. Compared with benign lesions, malignant tumors are quite rare, so those with less experience are advised--in case of doubt--to carry out a reference evaluation, since further imaging, e.g., costly magnetic resonance imaging (MRI), is in general not of any help for diagnosis. Only when malignancy is suspected or to plan biopsy is MRI, however, not only desirable to outline the malignant lesion in bone and soft tissue, but is an absolutely necessary in modern interdisciplinary treatment concepts, without which extremity-conserving surgery with constantly increasing life expectancy together with the considerable success of chemotherapy would be unthinkable.

Biopsy↗

PubMed1996

[Intramedullary nailing in callus distraction].

Intramedullary nailing is an established fixation method in fracture treatment as well as in deformity-correction procedures on tubular bones. The interlocking nail has increased the potential for employing the intramedullary nail in the treatment of fractures in metaphysial regions. Recent developments are biased towards the use of small-diameter unreamed nails, preferably made of titanium. Callus distraction, the controlled continuous shifting of corticotomized bone, leads to new bone formation and has been known since the beginning of this century. This method, however, gained wide acceptance and popularity through the work of Ilizarov. This paper describes a fusion of the two methods into a very promising management concept for substantial bone defects resulting from trauma or resection of bone tumors, as well as for the correction of congenital or acquired uni- or bilateral differences in length of the extremities. Various systems such as the combination of callus distraction by external fixation over an intramedullary nail and a fully implantable system are presented.

External Fixators↗

PubMed1996

[Perspectives in callus distraction].

Callus distraction is an enrichment of the surgical orthopaedic way of reconstructing bone defects, but it is also an effective method of lengthening limbs. The biological facts correspond to our knowledge about fracture healing. Concerning apparatures, further development is needed. In certain cases the ring fixator is the method of choice, but in most indications it is not necessary. Every effort should be made to adapt modern technologies, including fully implantable systems, to the "biological method" of callus distraction, whenever possible.

Bone Lengthening↗

PubMedDate not supplied

Do computers teach better? A media comparison study for case-based teaching in radiology.

A prospective study was performed to better define the role of computers in teaching radiology to medical students. Two hundred twenty-five 3rd-year students were randomly assigned to one of four groups and exposed to 10 radiology cases as well as to a voluntary weekly radiology lecture. Group A used computer-based cases with interactive elements; group B used computer-based cases without interactive elements; group C used paper-based cases with interactive elements; and group D was not exposed to the cases and served as a control group. On a multiple-choice question test, groups A, B, and C showed significant improvement (+11.2%, +15.1%, and +13.0%, respectively), whereas group D did not (+0.6%). On an image interpretation test, group A showed the most improvement (+15.7% [P <.001]), followed by group B (+15.1% [P <.01]) and group C (+10.2% [P <.05]); group D showed no significant improvement (+8.5%). No significant differences in the learning outcome were found between the two interactive groups (computer based and paper based). Computer-based teaching with case studies (with or without interactivity) improves students' problem-solving ability in radiology.

Chi-Square Distribution↗