In vivo whole body dosimetry measurement technique of total body irradiation: a 12-year retrospective study result from one institute in Thailand.

Objective: The main problem of total body irradiation (TBI) is how to maintain radiation dose homogeneity throughout the body during a treatment course. The simple set up treatment with non-complicated in vivo dosimetry measurement technique is the ideal method to solve this problem. For this reason, the authors have reported the results of in vivo dosimetry measurement method to prove the reliability of dose distribution from the authors' TBI technique.

Material And Method: The authors reviewed the data of dose measurement record from 53 patients' treatment files to report the uniformity of absorbed in vivo dose distribution throughout the whole body from TBI with semiconductor detectors and ionization chamber with the accepted homogeneity within +/- 10% of the prescribed dose. The result was reported in the term of mean and standard deviation of absorbed dose difference from the prescribed dose.

Results: The uniformity of radiation dose distribution throughout the whole body of all patients calculated from semiconductors was accepted with mean difference value of -3.2 +/- 2.5% from the prescribed dose and the difference of mean absorbed dose value at midline point between semiconductor and ionization chamber was 4 +/- 3.3%.

Conclusion: This TBI dosimetry measurement technique has been proved to exhibit the reliability of dose homogeneity throughout the whole body within the accepted value. This could be applied for use at any institute that has some limitation in resources and small treatment room.