Clinical implementation and impact of real-time Cherenkov imaging for treatment verification and patient safety in radiation therapy.

BACKGROUND AND PURPOSE: Real-time Cherenkov imaging (CI) visualizes surface dose distribution during external beam radiotherapy (EBRT). Although feasibility has been demonstrated, sustained multi-site implementation with predefined clinical impact metrics remains less well characterized. We evaluated clinic-wide CI integration across two centers over two years and quantified clinical impact, timing of detection, and corrective actions.

MATERIALS AND

METHODS

CI (DoseRT, Vision RT) was incorporated into routine treatment delivery on Varian TrueBeam linear accelerators. All techniques (3D, IMRT, SRS/SBRT) were monitored prospectively. Findings were assigned the highest plan-level clinical impact category: 0-1 (informational/non-actionable), 2 (setup refinement), 3 (workflow/planning modification), and 4 (immediate intervention). During implementation, mandatory physics review of CI images from the first five fractions of new treatment starts was adopted. Outcomes included actionable rate (Categories 2-4), time to first detection, and corrective endpoints (replanning, workflow changes).

RESULTS

Among 1,196 plans, 15% were actionable (Category 2: 8%; Category 3: 4%; Category 4: 3%). Twenty-one plans (1.8%) required partial or full replanning and 30 (2.5%) prompted workflow or policy modifications. Approximately half of Category 4 deviations were identified during beam-on and required immediate interruption and correction. Deviations were concentrated in early fractions: 76% were detected by fraction 3 and 89% by fraction 5 (median 2.6).

CONCLUSIONS

Clinic-wide CI integration is feasible and identifies actionable deviations in 15% of treatment plans, predominantly within the first five fractions. Real-time visualization supported immediate intervention and system-level workflow refinement without measurable disruption to clinical throughput, supporting CI as a complementary verification layer to IGRT/SGRT for patient safety.