Abstract

Background: The objective of this study was to estimate the dose received by the spinal cord and the esophagus by the use of TLD in a Plexiglas phantom.

Methods: The study was carried out with a Plexiglas phantom that was specifically designed for this purpose. Three Plexiglas phantoms of the neck and upper mid thoracic area were built based on the specifications of “reference man” and Body Mass Index (B.M.I) by the use of Corel Draw 8 software. The phantoms were heavy, medium and light built in size. The dose was determined by placing TLD cheaps at each marked location inside each phantom and exposing them to radiation for ten different set-ups.

Results: Based on different measurements it was concluded that using a gantry angle of 57o, a 30o wedge and a 15o rotation of the head of the table toward the gantry head will result in esophagus and spinal cord receiving the maximum and minimum dose respectively.

Conclusion: Based on our results a better dose homogeneity is achieved for dose delivered to esophagus than corresponding values for spinal cord.

Keywords: Radiotherapy; Phantom; Plexiglas; Absorbed dose; TLD