Significance: Benign external hydrocephalus (BEH) is considered a self-limiting pathology with a good prognosis. However, some children present a pathological intracranial pressure (ICP) characterized by quantitative and qualitative alterations (the so-called B-waves) that can lead to neurological sequelae.
Aim: Our purpose was to evaluate whether there were cerebral hemodynamic changes associated with ICP B-waves that could be evaluated with noninvasive neuromonitoring.
Approach: We recruited eleven patients (median age 16 months, range 7 to 55 months) with BEH and an unfavorable evolution requiring ICP monitoring. Bedside, nocturnal monitoring using near-infrared time-resolved and diffuse correlation spectroscopies synchronized to the clinical monitoring was performed.
Results: By focusing on the timing of different ICP patterns that were identified manually by clinicians, we detected significant tissue oxygen saturation ( ) changes ( ) and blood flow index (BFI) variability ( ) between regular and high-amplitude B-wave patterns. A blinded analysis looking for analogs of ICP patterns in BFI time traces achieved 90% sensitivity in identifying B-waves and 76% specificity in detecting the regular patterns.
Conclusions: We revealed the presence of and BFI variations-detectable with optical techniques-during ICP B-waves in BEH children. Finally, the feasibility of detecting ICP B-waves in hemodynamic time traces obtained noninvasively was shown.
Keywords: benign enlargement of subarachnoid spaces; hydrocephalus; intracranial pressure monitoring; optical techniques; pathophysiology.
© 2022 The Authors.