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51. A Multicenter Large Retrospective Database On The Personalization Of Stereotactic Ablative Radiotherapy For Lung Metastases From Colon-rectal Cancer: Early Results From The LaIT-SABR Study

Author

Nicosia, L., primary, Rigo, M., additional, Franceschini, D., additional, Scorsetti, M., additional, Perrone, F., additional, Osti, M.F., additional, Ravasio, A., additional, Vavassori, V., additional, Borghetti, P., additional, Magrini, S., additional, Bruni, A., additional, Frassinelli, L., additional, Lohr, F., additional, Di Marzo, A., additional, Maranzano, E., additional, Slimani, S., additional, De Bari, B., additional, Mazzola, R., additional, and Alongi, F., additional

Published
2020
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54. PH-0118: Stereotactic or conventional RT for macroscopic prostate bed recurrence: a propensity score analysis

Author

Francolini, G., primary, Jereczek-Fossa, B.A., additional, Di Cataldo, V., additional, Simontacchi, G., additional, Marvaso, G., additional, Zerella, M.A., additional, Gentile, P., additional, Bianciardi, F., additional, Allegretta, S., additional, Detti, B., additional, Masi, L., additional, Ciccone, L.P., additional, Bruni, A., additional, Ingrosso, G., additional, Mazzeo, E., additional, Trippa, F., additional, Lohr, F., additional, and Livi, L., additional

Published
2020
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56. 492P A multicenter LArge retrospectIve daTabase on the personalization of Stereotactic ABlative Radiotherapy for lung metastases from colorectal cancer: Early results from the LaIT-SABR study

Author

Nicosia, L., primary, Rigo, M., additional, Franceschini, D., additional, Scorsetti, M., additional, Congedi, F. Perrone, additional, Osti, M.F., additional, Ravasio, A., additional, Vavassori, V., additional, Borghetti, P., additional, Magrini, S.M., additional, Bruni, A., additional, Frassinelli, L., additional, Lohr, F., additional, Di Marzo, A., additional, Maranzano, E., additional, De Bari, B., additional, Mazzola, R., additional, and Alongi, F., additional

Published
2020
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57. IMRT for breast. A planning study

Author

Fogliata, A., Nicolini, G., Alber, M., Asell, M., Dobler, B., El-Haddad, M., Hårdemark, B., Jelen, U., Kania, A., Larsson, M., Lohr, F., Munger, T., Negri, E., Rodrigues, C., and Cozzi, L.

Published
2005
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62. Linee Guida AIRO-AIRB 2018: Neoplasie della Vescica

Author

Magrini, S., Santoni, R., Alongi, F., Arcangeli, S., Augurio, A, Belgioia, L., Bellavita, R., Bertone, F., Borghesi, S., Bruni, A., Buglione, M., Cardone, G., Corvò, R., D'Agostino, Gr, D'Angelillo, Rm, Fersino, S., Genovesi, D., Hurle, R., Ingrosso, G, Jereczek-Fossa, Ba, Lohr, F, Maccagnano, C, Mazzeo, E, Mortellaro, G., Munari, E., Muto, M., Nolà, F., Palumbo, I., Pasinetti, N., Silvestro, G., and Triggiani, L.

Subjects
Cancer Research, Urinary Bladder Neoplasms, Oncology, Humans, General Medicine
Published
2018

63. Fully automated, multi-criterial planning for Volumetric Modulated Arc Therapy – An international multi-center validation for prostate cancer

Author

Heijmen, B, Voet, P, Fransen, D, Penninkhof, J, Milder, M, Akhiat, H, Bonomo, Pierluigi, Casati, Marta, Georg, D, Goldner, G, Henry, A, Lilley, J, Lohr, F, Marrazzo, Livia, Pallotta, Stefania, Pellegrini, R, Seppenwoolde, Y, Simontacchi, Gabriele, Steil, V, Stieler, F, Wilson, S, and Breedveld, S

Subjects
Automated multi-criterial treatment planning, Knowledge-based planning, Multi-center validation, Prostate, VMAT
Published
2018

71. Automated VMAT planning for postoperative adjuvant treatment of advanced gastric cancer

Author

Sharfo, A.W.M. (Abdul Wahab), Stieler, F. (Florian), Kupfer, O. (Oskar), Heijmen, B.J.M. (Ben), Dirkx, M.L.P. (Maarten), Breedveld, S. (Sebastiaan), Wenz, F. (Frederik), Lohr, F. (Frank), Boda-Heggemann, J. (Judit), Buergy, D. (Daniel), Sharfo, A.W.M. (Abdul Wahab), Stieler, F. (Florian), Kupfer, O. (Oskar), Heijmen, B.J.M. (Ben), Dirkx, M.L.P. (Maarten), Breedveld, S. (Sebastiaan), Wenz, F. (Frederik), Lohr, F. (Frank), Boda-Heggemann, J. (Judit), and Buergy, D. (Daniel)

Abstract

Background: Postoperative/adjuvant radiotherapy of advanced gastric cancer involves a large planning target volume (PTV) with multi-concave shapes which presents a challenge for volumetric modulated arc therapy (VMAT) planning. This study investigates the advantages of automated VMAT planning for this site compared to manual VMAT planning by expert planners. Methods: For 20 gastric cancer patients in the postoperative/adjuvant setting, dual-arc VMAT plans were generated using fully automated multi-criterial treatment planning (autoVMAT), and compared to manually generated VMAT plans (manVMAT). Both automated and manual plans were created to deliver a median dose of 45 Gy to the PTV using identical planning and segmentation parameters. Plans were evaluated by two expert radiation oncologists for clinical acceptability. AutoVMAT and manVMAT plans were also compared based on dose-volume histogram (DVH) and predicted normal tissue complication probability (NTCP) analysis. Results: Both manVMAT and autoVMAT plans were considered clinically acceptable. Target coverage was similar (manVMAT: 96.6±1.6%, autoVMAT: 97.4±1.0%, p=0.085). With autoVMAT, median kidney dose was reduced on average by >25%; (for left kidney from 11.3±2.1 Gy to 8.9±3.5 Gy (p=0.002); for right kidney from 9.2±2.2 Gy to 6.1±1.3 Gy (p< 0.001)). Median dose to the liver was lower as well (18.8±2.3 Gy vs. 17.1±3.6 Gy, p=0.048). In addition, Dmax of the spinal cord was significantly reduced (38.3±3.7 Gy vs. 31.6±2.6 Gy, p< 0.001). Substantial improvements in dose conformity and integral dose were achieved with autoVMAT plans (4.2% and 9.1%, respectively; p< 0.001). Due to the better OAR sparing in the autoVMAT plans compared to manVMAT plans, the predicted NTCPs for the left and right kidney and the liver-PTV were significantly reduced by 11.3%, 12.8%, 7%, respectively (p≤0.001). Delivery time and total number of monitor units were increased in autoVMAT plans (from 168±19 s to 207±26 s, p=0.006) and (from 7

Published
2018
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73. Disease-specific and general health-related quality of life in newly diagnosed prostate cancer patients: The Pros-IT CNR study

Author

Porreca, A., Noale, M., Artibani, W., Bassi, P. F., Bertoni, F., Bracarda, S., Conti, G. N., Corvo, R., Gacci, M., Graziotti, P., Magrini, S. M., Mirone, V., Montironi, R., Muto, G., Pecoraro, S., Ricardi, U., Russi, E., Tubaro, A., Zagonel, V., Crepaldi, G., Maggi, S., Alitto, A. R., Ambrosi, E., Antonelli, A., Aristei, C., Barbieri, M., Bardari, F., Bardoscia, L., Barra, S., Bartoncini, S., Basso, U., Becherini, C., Bellavita, R., Bergamaschi, F., Berlingheri, S., Berruti, A., Borghesi, M., Bortolus, R., Borzillo, V., Bosetti, D., Bove, G., Bove, P., Maurizio, B., Alessio, B., Giorgio, B., Eugenio, B., Alberto, B., Michela, B., Consuelo, B., Giovanni, C., Michela, C., Giuseppe, C., Giorgio, C., Emanuele, C., Elisabetta, C., Gianpiero, C., Susanna, C., Catucci, F., Dario, C. F., Ofelia, C., Antonio, C., Francesco, C., Tommaso, C., Claudia, C., Devis, C., Franco, C., Matteo, C., Paolo, C., Fiorenza, C., Luigi, C., Cosimo, N., Cristiano, O., D'angelillo, R. M., Da Pozzo, L., D'agostino, D., D'elia, C., Dandrea, M., De Angelis, M., De Angelis, P., De Cobelli, O., De Concilio, B., De Lisa, A., De Luca, S., De Stefani, A., Deantoni, C. L., Degli, E. C., Destito, A., Detti, B., Di Muzio, N., Di Stasio, A., Di Stefano, C., Di Trapani, D., Difino, G., Falivene, S., Farullo, G., Fedelini, P., Ferrari, I., Ferrau, F., Ferro, M., Fodor, A., Fontanta, F., Francesca, F., Francolini, G., Frata, P., Frezza, G., Gabriele, P., Galeandro, M., Garibaldi, E., Gennari, P. G., Gentilucci, A., Giacobbe, A., Giussani, L., Giusti, G., Gontero, P., Guarneri, A., Guida, C., Gurioli, A., Huqi, D., Imbimbo, C., Ingrosso, G., Iotti, C., Italia, C., La Mattina, P., Lamanna, E., Lastrucci, L., Lazzari, G., Liberale, F., Liguori, G., Lisi, R., Lohr, F., Lombardo, R., Lovisolo, J. A. J., Ludovico, G. M., Macchione, N., Maggio, F., Malizia, M., Manasse, G., Mandoliti, G., Mantini, G., Marafioti, L., Marciello, L., Marconi, A. M., Martilotta, A., Marzano, S., Masciullo, S., Maso, G., Massenzo, A., Mazzeo, E., Mearini, L., Medoro, S., Mole, R., Monesi, G., Montanari, E., Montefiore, F., Montesi, G., Morgia, G., Moro, G., Muscas, G., Musio, D., Muto, P., Muzzonigro, G., Napodano, G., Negro, C. L. A., Nidini, M., Ntreta, M., Orsatti, M., Palazzolo, C., Palumbo, I., Parisi, A., Parma, P., Pavan, N., Pericolini, M., Pinto, F., Pistone, A., Pizzuti, V., Platania, A., Polli, C., Pomara, G., Ponti, E., Porcaro, A. B., Porpiglia, F., Pugliese, D., Pycha, A., Raguso, G., Rampini, A., Randone, D. F., Roboldi, V., Roscigno, M., Ruggieri, M. P., Ruoppo, G., Sanseverino, R., Santacaterina, A., Santarsieri, M., Santoni, R., Scagliarini, S., Scagliotti, G. V., Scanzi, M., Scarcia, M., Schiavina, R., Sciarra, A., Sciorio, C., Scolaro, T., Scuzzarella, S., Selvaggio, O., Serao, A., Serni, S., Signor, M. A., Silvani, M., Silvano, G., Silvestris, F., Simeone, C., Simone, V., Spagnoletti, G., Spinelli, M. G., Squillace, L., Tombolini, V., Toninelli, M., Triggiani, L., Trinchieri, A., Trodella, L. E., Trodella, L., Trombetta, C., Tronnolone, L., Tucci, M., Urzi, D., Valdagni, R., Valeriani, M., Vanoli, M., Vitali, E., Volpe, A., Zaramella, S., Zeccolini, G., Zini, G., Porreca A., Bassi P. F. (ORCID:0000-0002-4313-8427), Alitto A. R., Bove P., D'angelillo R. M., Guarneri A., Mantini G. (ORCID:0000-0001-5303-4499), Porreca, A., Noale, M., Artibani, W., Bassi, P. F., Bertoni, F., Bracarda, S., Conti, G. N., Corvo, R., Gacci, M., Graziotti, P., Magrini, S. M., Mirone, V., Montironi, R., Muto, G., Pecoraro, S., Ricardi, U., Russi, E., Tubaro, A., Zagonel, V., Crepaldi, G., Maggi, S., Alitto, A. R., Ambrosi, E., Antonelli, A., Aristei, C., Barbieri, M., Bardari, F., Bardoscia, L., Barra, S., Bartoncini, S., Basso, U., Becherini, C., Bellavita, R., Bergamaschi, F., Berlingheri, S., Berruti, A., Borghesi, M., Bortolus, R., Borzillo, V., Bosetti, D., Bove, G., Bove, P., Maurizio, B., Alessio, B., Giorgio, B., Eugenio, B., Alberto, B., Michela, B., Consuelo, B., Giovanni, C., Michela, C., Giuseppe, C., Giorgio, C., Emanuele, C., Elisabetta, C., Gianpiero, C., Susanna, C., Catucci, F., Dario, C. F., Ofelia, C., Antonio, C., Francesco, C., Tommaso, C., Claudia, C., Devis, C., Franco, C., Matteo, C., Paolo, C., Fiorenza, C., Luigi, C., Cosimo, N., Cristiano, O., D'angelillo, R. M., Da Pozzo, L., D'agostino, D., D'elia, C., Dandrea, M., De Angelis, M., De Angelis, P., De Cobelli, O., De Concilio, B., De Lisa, A., De Luca, S., De Stefani, A., Deantoni, C. L., Degli, E. C., Destito, A., Detti, B., Di Muzio, N., Di Stasio, A., Di Stefano, C., Di Trapani, D., Difino, G., Falivene, S., Farullo, G., Fedelini, P., Ferrari, I., Ferrau, F., Ferro, M., Fodor, A., Fontanta, F., Francesca, F., Francolini, G., Frata, P., Frezza, G., Gabriele, P., Galeandro, M., Garibaldi, E., Gennari, P. G., Gentilucci, A., Giacobbe, A., Giussani, L., Giusti, G., Gontero, P., Guarneri, A., Guida, C., Gurioli, A., Huqi, D., Imbimbo, C., Ingrosso, G., Iotti, C., Italia, C., La Mattina, P., Lamanna, E., Lastrucci, L., Lazzari, G., Liberale, F., Liguori, G., Lisi, R., Lohr, F., Lombardo, R., Lovisolo, J. A. J., Ludovico, G. M., Macchione, N., Maggio, F., Malizia, M., Manasse, G., Mandoliti, G., Mantini, G., Marafioti, L., Marciello, L., Marconi, A. M., Martilotta, A., Marzano, S., Masciullo, S., Maso, G., Massenzo, A., Mazzeo, E., Mearini, L., Medoro, S., Mole, R., Monesi, G., Montanari, E., Montefiore, F., Montesi, G., Morgia, G., Moro, G., Muscas, G., Musio, D., Muto, P., Muzzonigro, G., Napodano, G., Negro, C. L. A., Nidini, M., Ntreta, M., Orsatti, M., Palazzolo, C., Palumbo, I., Parisi, A., Parma, P., Pavan, N., Pericolini, M., Pinto, F., Pistone, A., Pizzuti, V., Platania, A., Polli, C., Pomara, G., Ponti, E., Porcaro, A. B., Porpiglia, F., Pugliese, D., Pycha, A., Raguso, G., Rampini, A., Randone, D. F., Roboldi, V., Roscigno, M., Ruggieri, M. P., Ruoppo, G., Sanseverino, R., Santacaterina, A., Santarsieri, M., Santoni, R., Scagliarini, S., Scagliotti, G. V., Scanzi, M., Scarcia, M., Schiavina, R., Sciarra, A., Sciorio, C., Scolaro, T., Scuzzarella, S., Selvaggio, O., Serao, A., Serni, S., Signor, M. A., Silvani, M., Silvano, G., Silvestris, F., Simeone, C., Simone, V., Spagnoletti, G., Spinelli, M. G., Squillace, L., Tombolini, V., Toninelli, M., Triggiani, L., Trinchieri, A., Trodella, L. E., Trodella, L., Trombetta, C., Tronnolone, L., Tucci, M., Urzi, D., Valdagni, R., Valeriani, M., Vanoli, M., Vitali, E., Volpe, A., Zaramella, S., Zeccolini, G., Zini, G., Porreca A., Bassi P. F. (ORCID:0000-0002-4313-8427), Alitto A. R., Bove P., D'angelillo R. M., Guarneri A., and Mantini G. (ORCID:0000-0001-5303-4499)

Abstract

Background: The National Research Council (CNR) prostate cancer monitoring project in Italy (Pros-IT CNR) is an observational, prospective, ongoing, multicentre study aiming to monitor a sample of Italian males diagnosed as new cases of prostate cancer. The present study aims to present data on the quality of life at time prostate cancer is diagnosed. Methods: One thousand seven hundred five patients were enrolled. Quality of life is evaluated at the time cancer was diagnosed and at subsequent assessments via the Italian version of the University of California Los Angeles-Prostate Cancer Index (UCLA-PCI) and the Short Form Health Survey (SF-12). Results: At diagnosis, lower scores on the physical component of the SF-12 were associated to older ages, obesity and the presence of 3+ moderate/severe comorbidities. Lower scores on the mental component were associated to younger ages, the presence of 3+ moderate/severe comorbidities and a T-score higher than one. Urinary and bowel functions according to UCLA-PCI were generally good. Almost 5% of the sample reported using at least one safety pad daily to control urinary loss; less than 3% reported moderate/severe problems attributable to bowel functions, and sexual function was a moderate/severe problem for 26.7%. Diabetes, 3+ moderate/severe comorbidities, T2 or T3-T4 categories and a Gleason score of eight or more were significantly associated with lower sexual function scores at diagnosis. Conclusions: Data collected by the Pros-IT CNR study have clarified the baseline status of newly diagnosed prostate cancer patients. A comprehensive assessment of quality of life will allow to objectively evaluate outcomes of different profile of care.

Published
2018

76. Radiotherapy‐induced subclinical skin changes revealed by dynamic optical coherence tomography: a case‐controlled pilot study.

Author

Chello, C., Ciardo, S., Chester, J., Guanti, M., Farnetani, F., Guida, S., Sticchi, A., Giacobazzi, P., Meduri, B., Lohr, F., Pellacani, G., and Manfredini, M.

Subjects
OPTICAL coherence tomography, SKIN ulcers, PILOT projects, COHERENCE (Optics), RADIATION injuries, RADIODERMATITIS
Abstract

Radiotherapy-induced subclinical skin changes revealed by dynamic optical coherence tomography: a case-controlled pilot study Radiotherapy (RT) is often used in the treatment of several cancers, including breast cancer.1-3 However, RT can invoke toxic cutaneous effects, depending directly on the amount of RT irradiation and duration and individual clinical patient characteristics. Images (VivoSight SP ® sp D-OCT Michelson Diagnostics Ltd, Maidstone, Kent, UK) were acquired at the superior anterior axillary line that was directly included in the target region of one of the RT fractions, 21-28 days from final RT session (treatment group). [Extracted from the article]

Published
2022
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79. The problem of stray dogs

Author

GAMBLE, L., primary, GIBSON, A. D., additional, SHERVELL, K., additional, LOHR, F., additional, OTTER, I., additional, and MELLANBY, R.J., additional

Published
2018
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83. OC-0299: Inconsistencies in clinicians‘ final treatment plan evaluations – a need for automation support

Author

Heijmen, B., primary, Bonomo, P., additional, Goldner, G., additional, Henry, A., additional, Lohr, F., additional, Simontacchi, G., additional, Voet, P., additional, Fransen, D., additional, Penninkhof, J., additional, Milder, M., additional, Akhiat, A., additional, Casati, M., additional, Georg, D., additional, Lilley, J., additional, Marrazzo, L., additional, Pallotta, S., additional, Pellegrini, R., additional, Seppenwoolde, Y., additional, Steil, V., additional, Stieler, F., additional, Wilson, S., additional, and Breedveld, S., additional

Published
2018
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88. Flattening filter free beams from TrueBeam and Versa HD units: Evaluation of the parameters for quality assurance

Author

Fogliata, A, Fleckenstein, J, Schneider, F, Pachoud, M, Ghandour, S, Krauss, H, Reggiori, G, Stravato, A, Lohr, F, Scorsetti, M, and Cozzi, L

Subjects
dosimetric parameters, Quality Control, Engineering, flattening filter free beams, Radiotherapy Dosage, Particle Accelerators, Radiometry, Radiotherapy, Computer-Assisted
Abstract

Flattening filter free (FFF) beams generated by medical linear accelerators are today clinically used for stereotactical and non-stereotactical radiotherapy treatments. Such beams differ from the standard flattened beams (FF) in the high dose rate and the profile shape peaked on the beam central axis. Definition of new parameters as unflatness and slope for FFF beams has been proposed based on a renormalization factor for FFF profiles. The present study aims to assess the dosimetric differences between FFF beams generated by linear accelerators from different vendors, and to provide renormalization and parameter data of the two kinds of units.Dosimetric data from two Varian TrueBeam and two Elekta Versa HD linear accelerators, all with 6 and 10 MV nominal accelerating potentials, FF and FFF modes have been collected. Renormalization factors and related fit parameters according to Fogliata et al. ["Definition of parameters for quality assurance of flattening filter free (FFF) photon beams in radiation therapy," Med. Phys. 39, 6455-6464 (2012)] have been evaluated for FFF beams of both units and energies. Unflatness and slope parameters from profile curves were evaluated. Dosimetric differences in terms of beam penetration and near-the-surface dose were also assessed.FFF profile parameters have been updated; renormalization factors and unflatness from the Varian units are consistent with the published data. Elekta FFF beam qualities, different from the Varian generated beams, tend to express similar behaviour as the FF beam of the corresponding nominal energy. TPR20,10 for 6 and 10 MV FF and FFF TrueBeam beams are 0.665, 0.629 (6 MV) and 0.738, 0.703 (10 MV). The same figures for Versa HD units are 0.684, 0.678 (6 MV) and 0.734, 0.721 (10 MV).Renormalization factor and unflatness parameters evaluated from Varian and Elekta FFF beams are provided, in particular renormalization factors table and fit parameters.

Published
2016

91. Incidence and survival of secondary malignances (SM) in oropharingeal squamous cell carcinoma (OPSCC): A homogeneous single report institution

Author

Napolitano, M., primary, Bertolini, F., additional, D'Angelo, E., additional, Spallanzani, A., additional, Tassi, S., additional, Meduri, B., additional, Bettelli, S., additional, Depenni, R., additional, Ghidini, A., additional, Lohr, F., additional, Presutti, L., additional, and Cascinu, S., additional

Published
2017
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94. OC-0568: Accelerated PBI VS standard radiotherapy (IRMA trial): interim cosmetic and toxicity results

Author

Meduri, B., primary, Baldissera, A., additional, Galeandro, M., additional, Donini, E., additional, Tolento, G., additional, Giacobazzi, P., additional, Calmieri, T., additional, Vasilyeva, P., additional, Morganti, A.G., additional, Parisi, S., additional, Kaleci, S., additional, Lohr, F., additional, D'amico, R., additional, Poortmans, P.M., additional, Bertoni, F., additional, and Frezza, G.P., additional

Published
2017
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95. A machine learning tool for re-planning and adaptive RT: A multicenter cohort investigation

Author

Guidi, G., primary, Maffei, N., additional, Meduri, B., additional, D’Angelo, E., additional, Mistretta, G.M., additional, Ceroni, P., additional, Ciarmatori, A., additional, Bernabei, A., additional, Maggi, S., additional, Cardinali, M., additional, Morabito, V.E., additional, Rosica, F., additional, Malara, S., additional, Savini, A., additional, Orlandi, G., additional, D’Ugo, C., additional, Bunkheila, F., additional, Bono, M., additional, Lappi, S., additional, Blasi, C., additional, Lohr, F., additional, and Costi, T., additional

Published
2016
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96. Robustness of sweeping-window arc therapy treatment sequences against intrafractional tumor motion

Author

Fleckenstein, J, Hesser, J, Wenz, F, and Lohr, F

Subjects
Lung Neoplasms, Time Factors, Esophageal Neoplasms, robust planning, Radiotherapy Planning, Computer-Assisted, Respiration, organ motion, VMAT, Radiotherapy Dosage, interplay effects, Models, Biological, Motion, Stomach Neoplasms, Humans, time resolved dosimetry, Computer Simulation, Radiotherapy, Intensity-Modulated, Radiometry
Abstract

Due to the potentially periodic collimator dynamic in volumetric modulated arc therapy (VMAT) dose deliveries with the sweeping-window arc therapy (SWAT) technique, additional manifestations of dosimetric deviations in the presence of intrafractional motion may occur. With a fast multileaf collimator (MLC), and a flattening filter free dose delivery, treatment times close to 60 s per fraction are clinical reality. For these treatment sequences, the human breathing period can be close to the collimator sweeping period. Compared to a random arrangement of the segments, this will cause a further degradation of the dose homogeneity.Fifty VMAT sequences of potentially moving target volumes were delivered on a two dimensional ionization chamber array. In order to detect interplay effects along all three coordinate axes, time resolved measurements were performed twice--with the detector aligned in vertical (V) or horizontal (H) orientation. All dose matrices were then moved within a simulation software by a time-dependent motion vector. The minimum relative equivalent uniform dose EUDr,m for all breathing starting phases was determined for each amplitude and period. Furthermore, an estimation of periods with minimum EUD was performed. Additionally, LINAC logfiles were recorded during plan delivery. The MLC, jaw, gantry angle, and monitor unit settings were continuously saved and used to calculate the correlation coefficient between the target motion and the dose weighed collimator motion component for each direction (CC, LR, AP) separately.The resulting EUDr,m were EUDr,m(CCV) = (98.3 ± 0.6)%, EUDr,m(CCH) = (98.6 ± 0.5)%, EUDr,m(APV) = (97.7 ± 0.9)%, and EUDr,m(LRH) = (97.8 ± 0.9)%. The overall minimum relative EUD observed for 360(∘) arc midventilation treatments was 94.6%. The treatment plan with the shortest period and a minimum relative EUD of less than 97% was found at T = 6.1 s. For a partial 120(∘) arc, an EUDr,m = 92.0% was found. In all cases, a correlation coefficient above 0.5 corresponded to a minimum in EUD.With the advent of fast VMAT delivery techniques, nonrobust treatment sequences for human breathing patterns can be generated. These sequences are characterized by a large correlation coefficient between a target motion component and the corresponding collimator dynamic. By iteratively decreasing the maximum allowed dose rate, a low correlation coefficient and consequentially a robust treatment sequence are ensured.

Published
2015

98. Gliome

Author

Schmieder, K and Lohr, F

Published
2014

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