Commissioning of Tandem and Split Ring Applicator

Abstract

patients (15 catheters in total). The shift of the catheters related to the clips is visualized in Figure 1, sorted by the day of the additional CT scan. Only shifts within the CTV are considered. On the second day, the maximum shift was 5 mm, while the shifts were much larger on the third and fourth day. On 6 occasions we decided to make a new plan: once due to 200% isodose bridges, four times due to large shifts of the catheters, and once due to both. Conclusions: Position verification of the catheters was found to be necessary to achieve sufficient quality control. The decision was therefore made to extend the length of active dwell positions in the original plan by 4 mm at both sides, in order to compensate for shifts of the catheters on the second day. As a consequence, we decided to omit the second day CT evaluation as we are convinced that the treatment can safely be continued. However, on the third day, a CT scan has to be performed followed by a new plan if necessary. This procedure is now a regular part of each treatment.

Аnalysis of the technical and dosimetric characteristics of the brachytherapy afterloaders. Ring applicator

“…Однако это приводит к расхождению между запланированным и реальных положением ИИИ. Также геометрические характеристики канала для движения источника и самого аппликатора могут иметь отличия у одного производителя, что вносит дополнительные неопределенности при проведении брахитерапии рака шейки матки [3]. Отмечаются различия в правильности запланированного положения ИИИ в канале аппликатора до 6 мм [4,5].…”