- - - MSc student, Department of Medical Physics, Tehran University of Medical Sciences, Tehran, Iran
- - - PhD, Department of Medical Physics, Tehran University of Medical Sciences, Tehran, Iran
- - - MD, Oncology Specialist, Cancer Institute of Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran
- - - PhD, Department of Anatomy, Tehran University of Medical Sciences, Tehran, Iran

Background: The Total Skin Electron Therapy (TSET) targets the whole of skin using ۶ to ۱۰ MeV electrons in large field size and large Source to Surface Distance (SSD). Treatment in sleeping position leads to a better distribution of dose and patient comfort. Objective: This study aims to investigate the uniformity of absorbed dose in the sleeping Stanford technique on the Rando phantom using dosimetry.Material and Methods: It is an experimental study which was performed using ۶ MeV electron irradiation produced by Varian accelerator in the AP and PA positions with gantry angles of ۳۱۸/۳, ۰ and ۴۱/۵ degrees, and RAO, LAO, RPO and LPO with ۲۹۱/۴ gantry angle and ۴۵ degrees of collimator angle in the sleeping position. Results: The results show that the dose uniformity achieved in this technique is in the range of (۱۰۰ ± ۲۵%) and, the dose accuracy was ۶%. Conclusion: Total Skin Electron Therapy (TSET) technique in sleeping position is very suitable for elderly and disabled patients, and meets the required dose uniformity. Furthermore, the use of a flattening filter is recommended for the more dose distribution uniformity.

TSET, Film Dosimeters, Phantom, Dosage Radiotherapy