Treatment delivery time optimization of respiratory gated radiation therapy by application of audio-visual feedback.

PURPOSE The feasibility to use visually guided voluntary breath-hold with and without audio assistance to reduce the total treatment time was evaluated. MATERIALS AND METHODS Patients referred for gated SBRT received hypofractionation schedules for lung or liver treatments. The patients were treated with the Novalis system (BrainLAB AG, Feldkirchen, Germany) and IGRT was performed with ExacTrac5.0/NovalisBody allowing gated irradiation. Video glasses, used for visual feedback to guide voluntary breath-hold, allowed additional audio assistance during treatment. The technique was applied for 25 patients of whom 9 were treated in free breathing, 7 had only visual feedback and another 9 had both audio and visual feedback. RESULTS The delivery time of gated treatment during free breathing had an average value of 1.7 min/100 MU (SD 0.6 min/100 MU). The introduction of visual feedback reduced the average delivery time to 1.4 min/100 MU (SD 0.4 min/100 MU). The treatments with additional audio assistance indicated a significant reduction (p=0.004) of the average delivery time to 0.9 min/100 MU (SD 0.2 min/100 MU). CONCLUSION The introduction of visually guided voluntary breath-hold with audio assistance led to treatment times for gated radiation therapy approaching conformal beam delivery times, which made gated treatments applicable in conventional treatment time slots.

[1]  K. Lam,et al.  Improvement of CT-based treatment-planning models of abdominal targets using static exhale imaging. , 1998, International journal of radiation oncology, biology, physics.

[2]  R. Emery,et al.  Clinical experience using respiratory gated radiation therapy: comparison of free-breathing and breath-hold techniques. , 2004, International journal of radiation oncology, biology, physics.

[3]  D. Verellen,et al.  Assessment of secondary patient motion induced by automated couch movement during on-line 6 dimensional repositioning in prostate cancer treatment. , 2007, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.

[4]  Importing measured field fluences into the treatment planning system to validate a breathing synchronized DMLC-IMRT irradiation technique. , 2006, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.

[5]  Arthur L Boyer,et al.  Respiratory gated beam delivery cannot facilitate margin reduction, unless combined with respiratory correlated image guidance. , 2008, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.

[6]  Steve B. Jiang,et al.  The management of respiratory motion in radiation oncology report of AAPM Task Group 76. , 2006, Medical physics.

[7]  D. Findley,et al.  Physical characteristics of a miniature multileaf collimator. , 1999, Medical physics.

[8]  Dirk Verellen,et al.  Innovations in image-guided radiotherapy , 2008, Nature Reviews Cancer.

[9]  W. Stanford,et al.  Analysis of movement of intrathoracic neoplasms using ultrafast computerized tomography. , 1990, International journal of radiation oncology, biology, physics.

[10]  G Starkschall,et al.  Respiratory-driven lung tumor motion is independent of tumor size, tumor location, and pulmonary function. , 2001, International journal of radiation oncology, biology, physics.

[11]  M. Halliwell,et al.  Ultrasound quantitation of respiratory organ motion in the upper abdomen. , 1994, The British journal of radiology.

[12]  M. V. van Herk,et al.  Precise and real-time measurement of 3D tumor motion in lung due to breathing and heartbeat, measured during radiotherapy. , 2002, International journal of radiation oncology, biology, physics.

[13]  Dirk Verellen,et al.  X-ray-assisted positioning of patients treated by conformal arc radiotherapy for prostate cancer: comparison of setup accuracy using implanted markers versus bony structures. , 2007, International journal of radiation oncology, biology, physics.

[14]  J. Ciezki,et al.  Fluoroscopic study of tumor motion due to breathing: facilitating precise radiation therapy for lung cancer patients. , 2001, Medical physics.

[15]  R C Grimm,et al.  Respiratory kinematics of the upper abdominal organs: A quantitative study , 1992, Magnetic resonance in medicine.

[16]  C. Ling,et al.  Evaluation of respiratory movement during gated radiotherapy using film and electronic portal imaging. , 2002, International journal of radiation oncology, biology, physics.

[17]  Hui Yan,et al.  A phantom study on the positioning accuracy of the Novalis Body system. , 2003, Medical physics.

[18]  Patrick A Kupelian,et al.  Evaluation of an infrared camera and X-ray system using implanted fiducials in patients with lung tumors for gated radiation therapy. , 2006, International journal of radiation oncology, biology, physics.

[19]  Radhe Mohan,et al.  Patient training in respiratory-gated radiotherapy. , 2003, Medical dosimetry : official journal of the American Association of Medical Dosimetrists.

[20]  C C Ling,et al.  The deep inspiration breath-hold technique in the treatment of inoperable non-small-cell lung cancer. , 2000, International journal of radiation oncology, biology, physics.

[21]  V. Budach,et al.  Image guided respiratory gated hypofractionated Stereotactic Body Radiation Therapy (H-SBRT) for liver and lung tumors: Initial experience , 2006, Acta oncologica.

[22]  Dirk Verellen,et al.  Quality assurance of a system for improved target localization and patient set-up that combines real-time infrared tracking and stereoscopic X-ray imaging. , 2003, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.

[23]  M. Noppen,et al.  Percutaneous placement of marking coils before stereotactic radiation therapy of malignant lung lesions. , 2005, Journal of vascular and interventional radiology : JVIR.

[24]  Dirk Verellen,et al.  A (short) history of image-guided radiotherapy. , 2008, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.

[25]  V. Budach,et al.  Commissioning of a micro multi-leaf collimator and planning system for stereotactic radiosurgery. , 1999, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.

[26]  D Verellen,et al.  Optimal control of set-up margins and internal margins for intra- and extracranial radiotherapy using stereoscopic kilovoltage imaging. , 2006, Cancer radiotherapie : journal de la Societe francaise de radiotherapie oncologique.

[27]  Dirk Verellen,et al.  Setup accuracy of stereoscopic X-ray positioning with automated correction for rotational errors in patients treated with conformal arc radiotherapy for prostate cancer. , 2006, Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology.

[28]  R Mohan,et al.  Determining parameters for respiration-gated radiotherapy. , 2001, Medical physics.

[29]  Radhe Mohan,et al.  Audio-visual biofeedback for respiratory-gated radiotherapy: impact of audio instruction and audio-visual biofeedback on respiratory-gated radiotherapy. , 2006, International journal of radiation oncology, biology, physics.