Purpose: This study aimed to evaluate prostate volume changes and prostate motions during radiotherapy.Methods: In 2010, twenty-five patients were treated for prostate cancer by external beam radiotherapy with implanted fiducial markers. Coordinates of three gold markers on kilovoltage images were calculated daily. Volume changes in target structure were observed through changes in intermarker distances. Differences in patient position between laser-tattoo alignment and gold marker localization were evaluated. Intrafraction motion was assessed by measuring marker displacement on kilovoltage images acquired before and after fraction delivery. Results: Prostate shrinkage was observed in 60% of patients. The average shrinkage was 7% of the prostate’s initial volume. Corrections after laser-tattoo alignment remained mostly below 1 cm. The difference between marker centroid position on the actual images and the planning images was 2 ± 1 mm on average. The extension of intrafraction movements was 7.6 ± 0.2 mm on average. Conclusions: In our retrospective study, the possibility for prostate volume changes during radiotherapy was revealed. Intrafraction movements turned out to be the limiting factor in safety margin reduction., Linda Kašaová, Igor Sirák, Jan Jansa, Petr Paluska, Jiří Petera, and Literatura 16
Hradiště Vladař u Žlutic (okr. Karlovy Vary) unikalo až donedávna bližší pozornosti archeologů. Článek shrnuje současný stav našich poznatků o této lokalitě a o jejím zasazení do přírodního prostředí. Zároveň upozorňuje na potenciální význam hradiště v mladším pravěku Čech. Vladař se nedávno stal předmětem detailních průzkumů a sondáží v narušených místech. Z popisu dosavadního postupu výzkumu a základní charakteristiky nálezů (především zlomků keramiky) jsou vyvozeny závěry o osídlení v období Ha a LT. and Vladař hillfort, situated close to the town Žlutice, western Bohemia, has attained only little attention from archaeologists until very recently. This contribution provides a description of the current stage of our knowledge of the site, its environmental setting and possible significance in the Bohemian later prehistory (Bronze Age, Hallstatt and La-Tène periods). Vladař hillfort became a focus site for a currently running research project; its actual progress, basic description of the finds – mainly pottery fragments – and some outline of preliminary results about Ha and LT periods settlement are given.