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A new template technique has been developed for implanting hyperthermia catheters in the treatment of brain tumors. The technique utilizes an imaging template and a drill template which can be rigidly secured to the head with three skull screws. The anatomic and vascular information needed for hyperthermia treatment planning may be assessed with three-dimensional magnetic resonance (MR) imaging and angiography acquisitions which use a surface coil. In the companioning treatment planning system the catheter positions and lengths and the electrodes in the catheter can be interactively manipulated relative to the anatomy and vasculature. The visualization of the blood vessels relative to the template allows the minimization of the risk on intracranial hemorrhages. This template technique is useful for any brain tumor implants, especially when a large number of catheters are involved. A phantom test has shown that this procedure has an accuracy in the order of 1 mm provided that the MR-related geometry distortions are minimized. Index Terms - Brain implants, implantation template, interstitial hyperthermia, treatment planning.

Rhizoctonia solani is a plant pathogenic fungus with a wide host range. Host plant specificity within R. solani was analysed on seedlings grown aseptically on agar, which allowed continuous observation of both the fungus and the whole plant without disturbing the interaction. Symptom development on cauliflower, Arabidopsis, eggplant. tomato and potato by 32 R. solani isolates, belonging to six different anastornosis groups (AGs), was studied. Host plant specificity of isolates, as analysed by similarity clustering, was similar to AG-related host plant specificity as observed in the field, with AG3 isolates (except two avirulent strains) separating from the other isolates. Two R. solani isolates with a reciprocal pathogenicity on cauliflower and tomato were selected for further studies. These showed that in the pathogenic combination, R. solani isolates grew over the plant, adhered and formed infection structures, while in the nonpathogenic combination isolates grew over the plant, but neither adhesion nor the formation of infection structures occurred. From these data, it was concluded that host plant specificity is mediated in the early steps of the infection process. [ABSTRACT FROM AUTHOR]