An in-house timer for ART-specific extra time in gynecologic pelvic online adaptive radiation therapy.

Abstract

Online adaptive radiation therapy (ART) lengthens the session, but many published times report one interval and do not isolate ART-specific activity. We developed a console timer that records wall-clock timestamps for a defined event list, stores per-fraction ART settings, and exports Excel tables. ART-specific extra time extends from ART mode until plan approval. After verification on 100 simulated fractions, it was applied in 38 fan-beam CT-guided gynecologic pelvic online ART fractions (nine patients). Mean ART-specific extra time was 13.7 min within a 21.8-min session, dominated by optimization and target/organ-at-risk editing. It supports bottleneck audit under a shared event list.