Purpose or Case Report: Critically ill neonatal, cardiovascular, and pediatric ICU patients often cannot be transported for advanced imaging due to clinical instability, staffing, and monitoring needs. Our goal was to evaluate the potential of repurposing a mobile CT system for chest and abdominopelvic imaging in pediatric ICU patients.
Methods & Materials: We adapted a carbon fiber table for supine pediatric positioning in the mobile CT gantry. Chest and abdominopelvic protocols were developed based on the system’s FDA-approved pediatric head imaging capabilities.

A novel 3D-printed anthropomorphic pediatric phantom, which simulated a normal contrast-enhanced CT examination was scanned using the mobile CT and three fixed CT systems (Flash, Force, and Alpha). The phantom was first scanned using fixed protocol (constant kV, pitch, dose, recon kernel, thickness, and IR strength). Protocols were then refined to match clinical standard of care radiation doses reported with the IEC body dosimetry phantom. Quantitative image of the fixed reference protocol and clinical protocols were assessed using automated metrics: average global noise index (AGNI), mean noise power spectrum frequency (NPSfav), and lower modulation transfer function limiting frequency (MTF) at the skin-air boundary.
Results: The AGNI for the fixed parameter protocol was 10.2 HU vs. 7.7-10.0 HU for the On.site vs Flash/Force/Alpha. NPSfav and MTF were: 0.26 mm^-1 vs 0.25-0.28 mm^-1 and 0.56 mm^-1 vs 0.65-0.68 mm^-1 for the On.site vs Flash/Force/Alpha respectively.

The AGNI on clinical protocols for the pediatric chest, abdomen, and pelvis were: 13.4 HU vs 15.8-22.0 HU for the On.site vs Flash/Force/Alpha respectively. NPSfav and MTF were: 0.24 mm^-1 vs 0.26-0.29 mm^1 (NPS, and 0.28 mm^1 vs 0.57-0.73 mm^1(MTF) for the On.site vs Flash/Force/Alpha.
Conclusions: A currently clinically available mobile CT designed for pediatric head scanning can generate comparable quality images based on physical parameters of image quality at equivalent radiation doses when clinical acuity precludes transport to the radiology department. This protocol is currently undergoing IRB review and prospective scanning of this patient population will further evaluate the feasibility of our findings in real world clinical settings. This capability addresses an important need and fills a crucial gap in the imaging options and safety profile available to the pediatric intensive care team. The portability of such systems serve to increase imaging access to resource and access limited settings.