Hans P. A. Marijnissen

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The effect of hematoporphyrin derivative photoradiation on tumor and normal tissue microcirculation was studied microscopically in vivo on rats with mammary carcinomas transplanted into subcutis in transparent observation chambers. One day after i.p. injection of hematoporphyrin derivative (15 mg/kg), chambers were exposed to red light (632 +/- 2 nm, eight(More)
PURPOSE Recently a commercial Monte Carlo based IMRT planning system (Monaco version 1.0.0) was released. In this study the dosimetric accuracy of this new planning system was validated. METHODS Absolute dose profiles, depth dose curves, and output factors calculated by Monaco were compared with measurements in a water phantom. Different static on-axis(More)
BACKGROUND AND PURPOSE It is estimated that one third of the institutes applying clinical beta sources does not perform independent dosimetry. The Netherlands commission on radiation dosimetry (NCS) recently published recommended quality control procedures and detectors for the dosimetry of beta sources. The main issues of NCS Report 14 are summarized here.(More)
The in vivo wavelength dependence of hematoporphyrin derivative (HpD) photodynamic treatment (PDT) has been studied. Ears of 136 rats were treated at six red and four blue-green laser wavelengths (615-635, 488-514.5 nm). Hematoporphyrin derivative was administered intraperitoneally (15 mg/kg) and 24 h later both ears were irradiated, at different(More)
The effects of Hematoporphyrin Derivative Photoradiation Therapy (HpD-PRT) on Greene's amelanotic melanoma implanted into the anterior chamber of rabbits have been examined by biomicroscopy, fluorescein angiography and histopathology. The tumors were irradiated 24 hours after injection of HpD when both the porphyrin concentration and the porphyrin ratio(More)
Using fluorescence imaging, the tissue-localizing properties of five photosensitizers were studied in vivo in tumours in 'sandwich' observation chambers and in tumours growing on thigh muscle. The preliminary results indicate that of the three photodynamically active dyes tested (haematoporphyrin derivative, Photofrin II and aluminium phthalocyanine(More)
V ACKNOWLEDGEMENTS When writing a booklet about a topic that is under rapid development such as the clinical introduction of an advanced treatment technique like IMRT, there is a chance that at the time of publication many solutions might already be obsolete or replaced by other approaches. We therefore greatly appreciate very much that we got the latest(More)
BACKGROUND AND OBJECTIVE Light dosimetry for endobronchial photodynamic therapy is not very advanced to date. This study investigates the dependency of the fluence rate distribution in the bronchial wall on several parameters. STUDY DESIGN/MATERIALS AND METHODS A Monte Carlo model is employed for the illumination of a cylindrical cavity by a linear(More)
Photodynamic therapy (PDT) involves the activation of photosensitizing drugs by light of appropriate wavelength. The photosensitive agent Hematoporphyrin Derivative (HPD) appears to be preferentially retained in malignant tumors; irradiation of HPD-containing tissue by light of appropriate wavelength (625 nm) and dose leads to (tumor) tissue destruction.(More)