Linear Accelerator-Based Radiotherapy Simulation Using On-Board Kilovoltage Cone-Beam Computed Tomography for 3-Dimensional Volumetric Planning and Rapid Treatment in the Palliative Setting

Brandon A. Dyer, Chithra K. Nair, Charles E. Deardorff, Cari L. Wright, Julian R Perks, Shyam Rao

Research output: Contribution to journalArticle


BACKGROUND: Palliation of advanced disease using radiotherapy can create difficult clinical situations where standard computed tomography simulation and immobilization techniques are not feasible. We developed a linear accelerator-based radiotherapy simulation technique using nonstandard patient positioning for head and neck palliation using on-board kilovoltage cone-beam computed tomography for 3-D volumetric planning and rapid treatment. Material and Methods: We proved cone-beam computed tomography simulation feasibility for semi-upright patient positioning using an anthropomorphic phantom on a clinical Elekta-Synergy linear accelerator. Cone-beam computed tomography imaging parameters were optimized for high-resolution image reconstruction and to ensure mechanical clearance. The patient was simulated using a cone-beam computed tomography-based approach and the cone-beam computed tomography digital imaging and communications in medicine file was imported to the treatment planning software to generate radiotherapy target volumes. Rapid planning was achieved by using a 3-level bulk density correction for air, soft tissue, and bone set at 0, 1.0, and 1.4 g/cm3, respectively. RESULTS: Patient volumetric imaging was obtained through cone-beam computed tomography simulation and treatment was delivered as planned without incident. Bulk density corrections were verified against conventionally simulated patients where differences were less than 1%. Conclusion: We successfully developed and employed a semi-upright kilovoltage cone-beam computed tomography-based head and neck simulation and treatment planning method for 3-D conformal radiotherapy delivery. This approach provides 3-D documentation of the radiotherapy plan and allows tabulation of quantitative spatial dose information which is valuable if additional palliative treatments are needed in the future. This is a potentially valuable technique that has broad clinical applicability for benign and palliative treatments across multiple disease sites-particularly where standard supine simulation and immobilization techniques are not possible.

Original languageEnglish (US)
JournalTechnology in cancer research & treatment
StatePublished - Jan 1 2019



  • CBCT
  • cone-beam computed tomography
  • palliative radiotherapy
  • radiotherapy simulation
  • simulation techniques

ASJC Scopus subject areas

  • Oncology
  • Cancer Research

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