Introduction: An in-house developed tool was implemented and validated to investigate the skin surface, hepatic dome, and target displacement for stereotactic ablative radiotherapy (SABR) of thoracic/abdominal lesions using a Surface Guided Radiation Therapy (SGRT) system combined with 4D- images. Materials and methods: Fourteen consecutive patients with tumors near the hepatic dome undergoing SABR treatments were analyzed. For each patient, a planning 4D-CT and five 4D-CBCT images were acquired. The C-RAD technology was also used to register/monitor the position of the skin reference point (SRP) as an external marker representative of patient breathing. The 4D images were imported in the developed tool, and the absolute maximum height (Pmax,dome) of the hepatic dome on the ten respiratory phases was semi-automatically detected. Similarly, the contour of the skin surface was extracted in correspondence with the SRP position. The tool has been validated using an ad hoc modified moving phantom with pre-selected amplitudes and numbers of cycles. The Pearson correlation coefficients and Bland-Altman plots were calculated. Results: There was a strong correlation between the skin motion amplitude based on 4D-CBCT and the C-RAD in all the patients (0.90 ± 0.08). Similarly, the mean ± SD of Pearson correlation coefficients of skin and Pmax,dome movements registered by 4D-CT and 4D-CBCT were 0.90 ± 0.05 and 0.94 ± 0.05, respectively. The mean ± SD of Pearson correlation coefficients comparing the skin and Pmax,dome displacements within each imaging modality were 0.88 ± 0.05 and 0.90 ± 0.05 for 4D-CT and 4D-CBCT, respectively. The SRP displacement during the set-up imaging and the treatment delivery were similar in all the investigated patients. Similar results were obtained for the ad hoc modified phantom in the preliminary validation phase. Conclusion: The strong correlation between the tumor/ hepatic dome and skin displacements confirms that the SGRT approach can be considered appropriate for intra- and inter-fraction motion management in SABR therapy.

A novel tool for assessing the correlation of internal/external markers during SGRT guided stereotactic ablative radiotherapy treatments / Paolani G.; Strolin S.; Santoro M.; Della Gala G.; Tolento G.; Guido A.; Siepe G.; Morganti A.G.; Strigari L.. - In: PHYSICA MEDICA. - ISSN 1120-1797. - ELETTRONICO. - 92:(2021), pp. 40-51. [10.1016/j.ejmp.2021.10.021]

A novel tool for assessing the correlation of internal/external markers during SGRT guided stereotactic ablative radiotherapy treatments

Morganti A. G.;
2021

Abstract

Introduction: An in-house developed tool was implemented and validated to investigate the skin surface, hepatic dome, and target displacement for stereotactic ablative radiotherapy (SABR) of thoracic/abdominal lesions using a Surface Guided Radiation Therapy (SGRT) system combined with 4D- images. Materials and methods: Fourteen consecutive patients with tumors near the hepatic dome undergoing SABR treatments were analyzed. For each patient, a planning 4D-CT and five 4D-CBCT images were acquired. The C-RAD technology was also used to register/monitor the position of the skin reference point (SRP) as an external marker representative of patient breathing. The 4D images were imported in the developed tool, and the absolute maximum height (Pmax,dome) of the hepatic dome on the ten respiratory phases was semi-automatically detected. Similarly, the contour of the skin surface was extracted in correspondence with the SRP position. The tool has been validated using an ad hoc modified moving phantom with pre-selected amplitudes and numbers of cycles. The Pearson correlation coefficients and Bland-Altman plots were calculated. Results: There was a strong correlation between the skin motion amplitude based on 4D-CBCT and the C-RAD in all the patients (0.90 ± 0.08). Similarly, the mean ± SD of Pearson correlation coefficients of skin and Pmax,dome movements registered by 4D-CT and 4D-CBCT were 0.90 ± 0.05 and 0.94 ± 0.05, respectively. The mean ± SD of Pearson correlation coefficients comparing the skin and Pmax,dome displacements within each imaging modality were 0.88 ± 0.05 and 0.90 ± 0.05 for 4D-CT and 4D-CBCT, respectively. The SRP displacement during the set-up imaging and the treatment delivery were similar in all the investigated patients. Similar results were obtained for the ad hoc modified phantom in the preliminary validation phase. Conclusion: The strong correlation between the tumor/ hepatic dome and skin displacements confirms that the SGRT approach can be considered appropriate for intra- and inter-fraction motion management in SABR therapy.
2021
A novel tool for assessing the correlation of internal/external markers during SGRT guided stereotactic ablative radiotherapy treatments / Paolani G.; Strolin S.; Santoro M.; Della Gala G.; Tolento G.; Guido A.; Siepe G.; Morganti A.G.; Strigari L.. - In: PHYSICA MEDICA. - ISSN 1120-1797. - ELETTRONICO. - 92:(2021), pp. 40-51. [10.1016/j.ejmp.2021.10.021]
Paolani G.; Strolin S.; Santoro M.; Della Gala G.; Tolento G.; Guido A.; Siepe G.; Morganti A.G.; Strigari L.
File in questo prodotto:
Eventuali allegati, non sono esposti

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/864866
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? 1
  • Scopus 10
  • ???jsp.display-item.citation.isi??? ND
social impact