Women's tolerance of breast propagation-based phase-contrast computed tomography (PB-CT) positioning procedure.

Introduction: Propagation-based phase-contrast computed tomography (PB-CT) as an advanced experimental imaging modality for breast cancer detection is nearing its world-first clinical trial. Due to the stationary synchrotron X-ray beam, participants must be rotated to capture CT data, yet tolerance to this rotation remains unassessed.

Methods: Participants underwent a simulated PB-CT procedure involving breast cups fitting and bed rotations at 10, 20, and 30° per second (°/s). The 30°/s rotation was repeated under eyes-open, eyes-closed, and breath-held conditions. Comfort was assessed via the Fast Motion Sickness Scale (FMS), State-Trait Anxiety Inventory - State (STAI-S), comfort questionnaire, and debriefing questions. Statistical analysis included Wilcoxon tests (baseline vs. each speed), a Friedman test (across all speeds), and a Kruskal-Wallis test (breath-hold condition).

Results: Among 27 female participants (median age-range 30-39; interquartile range (IQR) 30-39, >50), 14 completed the breath-hold condition. FMS scores significantly increased at 20°/s (p = 0.002) and 30°/s (p < 0.001); however, median sickness scores remained low across all speeds and conditions, with a maximum median of 2 out of 20, where 0 represents "no sickness" and 20 "severe sickness." STAI-S scores show no significant changes across speeds and conditions, suggesting that while faster rotations may increase physical discomfort, discomfort is limited, and participants' anxiety remains unaffected.

Conclusion: Breast PB-CT 3D imaging can be comfortably conducted at rotation speeds relevant to future clinical trials.

Implications for practice: As PB-CT nears clinical translation, assessing procedural comfort is essential for developing patient-centered protocols that balance experience and image quality.