Scholarlink

<p>The impact of three-dimensional (3D) dose delivery accuracy of C-arm linacs on the planning target volume (PTV) margin was evaluated for non-coplanar intracranial stereotactic radiosurgery (SRS). A multi-institutional 3D starshot test using beams from seven directions was conducted at 22 clinics using Varian and Elekta linacs with X-ray CT-based polymer gel dosimeters. Variability in dose delivery accuracy was observed, with the distance between the imaging isocenter and each beam exceeding 1&#xa0;mm at one institution for Varian and nine institutions for Elekta. The calculated PTV margins for Varian and Elekta linacs that could cover the gross tumor volume with 95% probability at 95% of the institutions were 2.3 and 3.5&#xa0;mm, respectively, in the superior–inferior direction. However, with multifactorial system management (i.e., high-accuracy 3D dose delivery with rigorous linac quality assurance, strict patient immobilization, and high intra-fractional positioning accuracy), these margins could be reduced to 1.0&#xa0;mm and 1.5&#xa0;mm, respectively. The findings indicate significant millimeter-level variability in 3D dose delivery accuracy among linacs installed in clinical settings. Thus, maximizing a linac’s 3D dose delivery accuracy is essential to achieve the required PTV margin in intracranial SRS.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Spatial accuracy of dose delivery significantly impacts the planning target volume margin in linear accelerator-based intracranial stereotactic radiosurgery

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年1月29日

查看全文
  • Yuta Takahashi,
  • Riki Oshika,
  • Rie Tachibana,
  • Katsuyuki Shirai,
  • Hiroshi Asakura,
  • Masayoshi Miyazaki,
  • Tomohiro Sagawa,
  • Shinichi Takahashi,
  • Tsunekazu Kuwae,
  • Hironori Kojima,
  • Shiro Nishiyama,
  • Hikaru Nemoto,
  • Yoshitomo Ishihara,
  • Mariko Umeda,
  • Kotaro Kijima,
  • Daisuke Kobayashi,
  • Keiji Suzuki,
  • Yuki Nozawa,
  • Kento Hoshida,
  • Tomoki Kitagawa,
  • Hiromitsu Endo,
  • Yuki Matsunaga,
  • Hiroya Itagaki,
  • Mayumi Ishida,
  • Shigeru Kanahara,
  • Ryo Horita,
  • Daisuke Hori,
  • Hidenobu Tachibana

摘要

The impact of three-dimensional (3D) dose delivery accuracy of C-arm linacs on the planning target volume (PTV) margin was evaluated for non-coplanar intracranial stereotactic radiosurgery (SRS). A multi-institutional 3D starshot test using beams from seven directions was conducted at 22 clinics using Varian and Elekta linacs with X-ray CT-based polymer gel dosimeters. Variability in dose delivery accuracy was observed, with the distance between the imaging isocenter and each beam exceeding 1 mm at one institution for Varian and nine institutions for Elekta. The calculated PTV margins for Varian and Elekta linacs that could cover the gross tumor volume with 95% probability at 95% of the institutions were 2.3 and 3.5 mm, respectively, in the superior–inferior direction. However, with multifactorial system management (i.e., high-accuracy 3D dose delivery with rigorous linac quality assurance, strict patient immobilization, and high intra-fractional positioning accuracy), these margins could be reduced to 1.0 mm and 1.5 mm, respectively. The findings indicate significant millimeter-level variability in 3D dose delivery accuracy among linacs installed in clinical settings. Thus, maximizing a linac’s 3D dose delivery accuracy is essential to achieve the required PTV margin in intracranial SRS.