Noninvasive Neuromonitoring in Pediatric Traumatic Brain Injury: A Scoping Review of Quantitative Pupillometry and the Evidence Gap in Noninvasive Intracranial Pressure Waveform Analysis.

Pediatric traumatic brain injury (TBI) is the leading cause of injury-related death and long-term disability in children worldwide. Current monitoring relies predominantly on invasive techniques that carry procedural risks and are not feasible in all settings or across all severity levels. Noninvasive alternatives, including quantitative automated pupillometry and intracranial pressure (ICP) pulse waveform monitoring, have emerged as promising tools, yet their evidence base in pediatric TBI remains uncharacterized. We conducted a scoping review following the Joanna Briggs Institute methodology, reported per Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews, to characterize existing evidence on these two modalities, examining devices, populations, parameters, and key findings. Five databases (PubMed/MEDLINE, Embase, Cochrane Central, Scopus, CINAHL) were searched through February 2026. Six studies met the inclusion criteria, all addressing quantitative pupillometry. Three evaluated pupillometry in mild TBI in emergency or outpatient settings, one enrolled critically ill children with concurrent invasive ICP monitoring in the pediatric intensive care unit, and two reviewed pupillometry within multimodal neuromonitoring frameworks. All primary studies employed NeurOptics devices. Key findings included time-dependent alterations in pupillary light reflex following concussion and a significant inverse correlation between ICP and pupillometric parameters at thresholds ≥20 mmHg. No primary clinical study evaluated noninvasive ICP pulse waveform morphology devices, specifically P1/P2/P3 analysis characteristic of Brain4care-type technologies in children with TBI. Quantitative pupillometry shows physiologically coherent associations with TBI-related changes, but its utility remains limited by heterogeneous protocols, the absence of age-stratified normative values, and the lack of prospective outcome data. No primary pediatric evidence on noninvasive ICP waveform monitoring was identified, representing the highest-priority evidence gap.