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Updated: Aug 8, 2026
Treatment of Liver Metastases Using an Internal Target Volume Method for Stereotactic Body Radiotherapy
Published on: May 8, 2018
A Novel Motion-Management Workflow Using Abdominal Compression and Exhale Breath-Hold for Patients With Hepatobiliary
A Webster1, T Patel2, D Marsh2
1Medical Physics and Biomedical Engineering at UCL, UK; Radiotherapy and Proton Beam Therapy at UCLH, UK.
Aim:
Respiratory motion presents a significant challenge in liver radiotherapy. Abdominal compression (AC) and exhale breath‑hold (EBH) are established motion‑management techniques but are typically used independently. This study evaluated the feasibility, reproducibility, and patient‑level impact of combining AC and EBH as a novel, widely accessible motion‑management approach for patients with hepatobiliary malignancies.
Materials And Methods:
A retrospective single‑centre pre-treatment evaluation was conducted for patients referred for motion management. Pre‑treatment imaging comprised an unassisted EBH 3DCT and 4DCT in free breathing, all under compression. Endpoints included AC tolerance, residual liver dome motion under compression, EBH feasibility and reproducibility, and alignment of coached EBH with the free‑breathing exhale phase. Associations with patient characteristics were explored.
Results:
Seventy‑eight patients underwent 4DCT; 73/78 (93.6%) tolerated AC. Under compression, residual liver‑dome motion ranged from 0.5-18.3 mm (median 5.3 mm). EBH suitable for CT acquisition was achieved by 47/73 patients (64.4%), with an additional 13 patients sustaining breath‑holds of 10-15 seconds, indicating that shorter acquisition times could increase EBH eligibility. EBH was reproducible in 40/47 patients (85.1%), and the coached EBH position aligned with ≥6/10 4DCT phase bins in most cases. No patient characteristics reliably predicted residual motion or EBH feasibility.
Conclusion:
Combining AC and EBH is feasible, well tolerated, and provides complementary motion control using equipment already available in many radiotherapy departments. This approach offers a practical, accessible pathway to reduce residual motion and, in some patients, may limit ITV expansion, thereby supporting precise hepatobiliary radiotherapy within existing infrastructure. Prospective evaluation across multiple treatment fractions, alongside patient-reported experience measures, is required to optimise implementation.
