Comparative study on skin dose measurement using MOSFET and TLD for pediatric patients with acute lymphatic leukemia
Huda I. Al-Mohammed, Fareed H. Mahyoub, Belal A. Moftah
Med Sci Monit 2010; 16(7): CR325-329
Available online: 2010-06-25
Background: The object of this study was to compare the difference of skin dose measured in patients with acute lymphatic leukemia (ALL) treated with total body irradiation (TBI) using metal oxide semiconductor field-effect transistors (mobile MOSFET dose verification system (TN-RD-70-W) and thermoluminescent dosimeters (TLD-100 chips, Harshaw/ Bicron, OH, USA). Because TLD has been the most-commonly used technique in the skin dose measurement of TBI, the aim of the present study is to prove the benefit of using the mobile MOSFET (metal oxide semiconductor field effect transistor) dosimeter, for entrance dose measurements during the total body irradiation (TBI) over thermoluminescent dosimeters (TLD).
Material/Methods: The measurements involved 10 pediatric patients ages between 3 and 14 years. Thermoluminescent dosimeters and MOSFET dosimetry were performed at 9 different anatomic sites on each patient.
Results: The present results show there is a variation between skin dose measured with MOSFET and TLD in all patients, and for every anatomic site selected, there is no significant difference in the dose delivered using MOSFET as compared to the prescribed dose. However, there is a significant difference for every anatomic site using TLD compared with either the prescribed dose or MOSFET. The results indicate that the dosimeter measurements using the MOSFET gave precise measurements of prescribed dose. However, TLD measurement showed significant increased skin dose of cGy as compared to either prescribed dose or MOSFET group.
Conclusions: MOSFET dosimeters provide superior dose accuracy for skin dose measurement in TBI as compared with TLD.
Keywords: Thermoluminescent Dosimetry - methods, Skin - radiation effects, Semiconductors, Precursor Cell Lymphoblastic Leukemia-Lymphoma - radiotherapy, Dose-Response Relationship, Radiation, Child, Transistors, Electronic, Whole-Body Irradiation