Keywords
low- and middle-income countries
non-invasive monitoring
optic nerve sheath diameter
quantitative pupillometry
transcranial Doppler
Abstract
Intracranial hypertension is a major cause of secondary brain injury and adverse outcome following severe traumatic brain injury and other acute neurological conditions. Invasive intracranial pressure (ICP) monitoring remains the reference standard, but its availability is
inconsistent in low- and middle-income countries (LMICs). Non-invasive ICP (nICP) technologies, including optic nerve sheath diameter (ONSD) ultrasonography, transcranial Doppler (TCD), quantitative pupillometry and imaging-derived markers, offer potentially scalable alternatives. This narrative review summarizes the current evidence for clinically available nICP techniques and examines their integration into algorithm-based management in resource-constrained settings. Contemporary consensus recommendations, including the Brussels consensus for non-invasive ICP monitoring (B-ICONIC), and the Consensus REVised Imaging and Clinical Examination (CREVICE) and Seattle International Severe Traumatic Brain Injury Consensus Conference (SIBICC) treatment algorithms were
considered. ONSD ultrasonography, TCD and quantitative pupillometry provide complementary information but cannot currently reproduce the continuous and direct measurement obtained with invasive ICP monitoring. ONSD has demonstrated moderate
diagnostic accuracy for intracranial hypertension, whereas TCD-derived indices and quantitative pupillometry appear particularly useful for serial trend assessment. Their clinical value is greatest when integrated with neurological examination, physiological variables and
neuroimaging rather than interpreted as isolated numerical surrogates of ICP. A tiered algorithm incorporating clinical assessment, nICP assessment, basic ICP-lowering measures, hyperosmolar therapy, repeat assessment and timely neurosurgical referral is proposed for
LMIC settings. Algorithm-based implementation can facilitate early recognition of deterioration, standardize treatment escalation and improve the use of limited neurocritical care resources. Prospective validation of multimodal nICP algorithms in LMIC populations is urgently required.
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