Recognition of Intracranial Hypertension in Children using Handheld Optical Coherence Tomography: The RIO Diagnostic Accuracy Study

Abstract

Purpose : Intracranial hypertension (IH) can damage the brain and optic nerve head (ONH) if unaddressed, and intracranial pressure (ICP) monitoring is invasive and carries risk. In this world-first diagnostic accuracy study, we assessed the role of handheld optical coherence tomography (OCT) to recognise IH in children.

Methods : We conducted a multi-centre, prospective diagnostic accuracy study at Great Ormond Street Hospital and Oxford. Forty-two children at risk of IH were recruited between September 2020 and August 2022. Handheld OCT was attempted during invasive ICP monitoring. Inclusion criteria included aged (<18 years) and diagnosis: craniosynostosis, hydrocephalus, idiopathic IH (IIH), and other conditions associated with IH. Exclusion criteria included unsuccessful handheld OCT imaging. The surgeons measuring/interpreting ICP were masked to OCT findings. We considered ICP raised if the median reading was above 20mmHg, or prolonged ICP spikes were present. Positive OCT parameters included; i) anterior displacement of Bruch’s membrane; ii) raised rim and cup (bilaterally upward sloping rim with cup-base above level of disc edges); iii) cup obliteration (minimised cup with loss of ‘U’ shape; iv) atrophy (extremely thin retinal nerve fibre layer). Sensitivity/specificity analysis was performed and Fisher’s exact test was used to compare OCT parameters and ICP (raised/normal).

Results : Handheld OCT was successful in 41 of 42 (98%) eligible children. Diagnoses included craniosynostosis (n=26), hydrocephalus (n=9), IIH (n=2) and other (n=4). Median age at examination was 6.5 years (range: 0.5-17, IQR: 4-13). For all OCT parameters, sensitivity was 90% and specificity 75% for IH. Fisher’s exact test demonstrated a highly significant difference between OCT and ICP groups (p<0.001).

Conclusions : This world-first study suggests that handheld OCT is feasible and valuable for non-invasively recognising IH in children. Our findings could help improve the clinical management of children at risk of IH.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.