This thesis evaluates the use of deformable image registration (DIR) for dose accumulation in gynecological HDR brachytherapy. By comparing DIR-based and conservative methods, it assesses the impact of anatomical motion and registration accuracy on cumulative dose estimates to organs at risk and target volumes. The study highlights the clinical relevance of DIR, particularly for mobile organs like the small bowel and rectum, and supports the use of hybrid-based DIR for for improved accuracy.