Publications by authors named "H J Schwarzmaier"

We present a new technique to determine the scattering coefficient, the absorption coefficient, and the anisotropy factor in turbid media on a microscopic level. To this end, a microspectrophotometer was used to obtain transmission measurements at different solid angles. To extract the optical properties from phantom materials (liquid and solid) and biological tissue (bovine liver) an inverse Monte Carlo algorithm was used.

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We modified the diffusion approximation of the time-dependent radiative transfer equation to account for a finite scattering delay time. Under the usual assumptions of the diffusion approximation, the effect of the scattering delay leads to a simple renormalization of the light velocity that appears in the diffusion equation. Accuracy of the model was evaluated by comparison with Monte Carlo simulations in the frequency domain for a semi-infinite geometry.

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Purpose: Laser-induced interstitial thermotherapy (LITT) is a minimally invasive procedure for local tumor ablation. This report discusses the long-term results of this therapy in non-surgical patients with colorectal liver metastases.

Materials And Methods: In total, we treated 163 colorectal liver metastases in 85 patients by MR-guided LITT.

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We investigated the survival after laser-induced interstitial thermotherapy in 16 patients suffering from recurrent glioblastoma multiforme. The concept underlying the intervention is the cytoreduction of the tumor tissue by local thermocoagulation. All patients received standard chemotherapy (temozolomide).

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Stereotactic body radiotherapy (SBRT) is a high dose radiotherapy, the radiation dose is applicated one-time or in a few fractions exactly to the tumor or metastases under maximal separation from the normal tissue. Because of this a major expenditure of medical and technical efforts are necessary, a detailed description of the proceedings is following in the methodic part of this article. Indications of SBRT are especially medical irresectable lung tumors of early stages, primary liver/biliary tumors and pulmonary or liver metastases if there is an oncological benefit for the patients.

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