International Journal of Radiation Research

en Evaluation of a two-dimensional small field measurement array for stereotactic radiotherapy plan quality assurance Radiation Biology Radiation Biology تحقيق بديع Original Research <div style="text-align: justify;">Background: This study aimed to assess a two dimensional (2D) small field detector array for quality assurance (QA) in stereotactic radiotherapy (SRT), verify its key dosimetric properties, and evaluate its clinical performance for patient specific SRT plan verification. Materials and Methods: The myQA® SRS system comprises a 140 × 120 mm CMOS detector matrix with 400μm resolution, housed in a cylindrical ABS phantom. Tests included dose linearity, field size dependence, and beam angular response; clinical utility was validated via patient specific measurements. The detector’s sensitivity to deliberately introduced MLC positional shifts was also examined by simulating systematic MLC offsets and comparing measured doses with planned values. Results: The basic characteristic test of the detector met the recommended specifications. The maximum deviation in detector signal relative to baseline readings was 0.5 %. The detector exhibited excellent dose linearity (R² = 1). Output factors agreed within 1.5 % compared with ionization chamber (IC) measurements for field sizes above 1 cm. Angular dependence was evaluated by comparing calculated and measured relative doses, and a lookup table (LUT) was established and validated. For clinical patient plans, the detector yielded an average gamma pass rate of 97.8 % ± 1.3 % under the 3 %/1 mm criterion. The detector was sensitive to systematic MLC offsets larger than 0.2 mm at 3 %/1 mm. Conclusion: The myQA® SRS detector is validated as a reliable tool for stereotactic radiotherapy plan QA, capable of providing high resolution real time dosimetric results.</div> Radiometry, quality assurance, stereotactic body radiotherapy, stereotactic radiosurgery. 1175 1180 http://ijrr.com/browse.php?a_code=A-10-1-1630&slc_lang=en&sid=1 J. Gao 7900319475328460035129 7900319475328460035129 No Cancer Center, Hubei Key Laboratory of Precision Radiation Oncology, Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, China H. Wei 7900319475328460035130 7900319475328460035130 No Department of Radiotherapy, Affiliated Hospital of Hebei Engineering University, Hebei, China X. Nie 7900319475328460035131 7900319475328460035131 No Cancer Center, Hubei Key Laboratory of Precision Radiation Oncology, Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, China J. Yang 7900319475328460035132 7900319475328460035132 No Cancer Center, Hubei Key Laboratory of Precision Radiation Oncology, Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, China S. Zhang 7900319475328460035133 7900319475328460035133 No Cancer Center, Hubei Key Laboratory of Precision Radiation Oncology, Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, China H. Li 7900319475328460035134 7900319475328460035134 No Institute for Health Surveillance Analysis & Protection, Hubei Provincial Center for Disease Control and Prevention, Hubei, China Z. Liang 987542214@qq.com 7900319475328460035135 7900319475328460035135 Yes Cancer Center, Hubei Key Laboratory of Precision Radiation Oncology, Institute of Radiation Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, China