ABSTRACT
Brachytherapy was rst introduced at the beginning of the twentieth century, where the radioactive sources were manually implanted into the tumor, thereby subjecting the physician and other medical personnel to unwanted radiation exposure. In the middle of last century, most brachytherapy procedures were performed using manual aerloading techniques, where hollow needles or applicators were placed in the tumor volume and then radioactive sources placed in the needles or applicators, thereby reducing the radiation exposure. Remote aerloaders (RALs), where radioactive sources are placed remotely in the needles or applicators placed in the operating room, were introduced at the end of the last century, thereby minimizing the exposure to nurses and caregivers. Historically, rst low-dose-rate (LDR) and then 60Co-based high-dose-rate (HDR) technology was introduced. In the 1980s, programmable 137Cs Selectron-LDR
and later miniaturized 192Ir stepping sources for HDR and pulsed-dose-rate (PDR) applications became popular. Currently, new interest in use of other source types focusing both on high energy source (60Co in the aerloader of Eckert & Ziegler BEBIG GmbH) and low energy source (169Yb and 170Tm) is being introduced or is in the process of being tested clinically.
