ISSN 2167-0404
International Journal of Medicine and Medical Sciences ISSN: 2167-0404 Vol. 2 (11), pp. 236-244, November, 2012. © International Scholars Journals
Full Length Research Paper
Preliminary dosimetric evaluation of a designed head and neck phantom for intensity modulated radiation therapy (IMRT)
K. M. Radaideh1*, L. M. Matalqah2,3, A. A. Tajuddin4, W. I. Fabian Lee5 and S. Bauk6
1School of Physics, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia.
2School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia.
3School of Pharmacy, Allianze University College of Medical Sciences (AUCMS), 13200 Kepala Batas,
Penang, Malaysia.
4Advanced Medical and Dental Institute, Universiti Sains Malaysia, 13200 Kepala Batas, Penang, Malaysia.
5Department of Radiotherapy and Oncology, Mount Miriam Cancer Hospital, Jalan Bulan, 11200 Penang Malaysia.
6Physics Section, School of Distance Education, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia.
*Corresponding author. E-mail: [email protected]
Received 08 July, 2012; Accepted 16 November, 2012
Abstract
The aims of this paper are to design, construct, and evaluate an anthropomorphic head and neck phantom for dosimetric verification of nasopharyngeal cancer treatment plan using intensity modulated radiation therapy (IMRT) technique. The phantom was designed as an assembly of thirty nine (39) transversal section slabs fabricated from Perspex material each with delineated planning target volumes (PTVs) and organ at risk (OARs) regions. Thermoluminescent dosimeter (TLD) was used after multiple calibration cycles. The phantom was imaged, planned, and irradiated by IMRT plan. The reproducibility of phantom measurements was checked by three identical IMRT irradiations. Four (4) nasopharyngeal patients’ IMRT treatment plans were transferred to the phantom for dose verification. Phantom’s measured doses were reproducible with less than 3.5% standard deviation. For the verification of IMRT patient’s plans, the mean of percent dose differences between measured and calculated doses was found 6.2% (SD: 4.7) at OAR and 5.96% (SD: 2.5%) at PTV. The percentage dose deviation met the accuracy criteria of 7% at low dose regions. The standard deviation of TLD/TPS was 2.4% at PTV and 6.8% at OAR. This good agreement proves the feasibility of applying this phantom in IMRT dose verification.
Key words: Intensity modulated radiation therapy (IMRT) verification, head and neck phantom, thermoluminescent.