ABSTRACT
This chapter describes the current clinical practice for transrectal ultrasound (TRUS), computed tomography (CT), and magnetic resonance imaging (MRI)-based applicator reconstruction. It focuses on electromagnetic tracking (EMT), special techniques in MRI, and vibro-acoustography (VA). TRUS is the typical imaging modality to supervise needle implantation for permanent low-dose rate (LDR) seed implantation and interstitial prostate high-dose rate (HDR)-brachytherapy with the patient in dorsal lithotomy position. CT is the main imaging option for implant reconstruction in interstitial brachytherapy for breast, head, and neck, and also for post-planning of seed implants in the prostate. EMT refers to a technology that allows measuring the position of miniaturized sensors in three-dimensional (3D) space often combined with additional degrees of freedom (DOF) for the orientation of the sensor. EMT is used in a variety of medical applications including tracking of surgical instruments, guidance of biopsies and external beam radiation therapy.
