Advances in patient positioning

New technologies and processes have allowed for advances in patient positioning. Indexed immobilization allows clinicians to enhance treatment effectiveness and maximize clinical efficiency. When the same patient positioning system and couch are used in simulation and in the treatment room it is feasible to ensure identical patient setups between simulation and treatment. The emergence of 3-D conformal therapy and IMRT have lead the radiotherapy community to place increased importance and need for accurate patient positioning. As a result, radiotherapy vendors, as well as many radiation oncology departments, have developed their own immobilization devices to reduce patient setup time and ensure exact repeat positioning. Indexed immobilization is intended to facilitate precise repeatable patient positioning both in moving from simulation to treatment and in standardizing day-to-day set-ups. In addition to precise patient positioning, indexed immobilization can significantly reduce the length of treatment sessions by reducing patient movement and by standardizing the placement and set-up of immobilization devices. Coupled with the use of 3D treatment planning capability, precise positioning can facilitate treatments for flat or wedged conformal therapy and Intensity Modulated Radiation Therapy (IMRT). This article summarizes the features and operational benefits of indexed immobilization and then outlines the implications for clinical and departmental processes. The most significant benefits come when the user's processes are modified to take advantage of the enabling technology.