Application of transcranial transmission ultrasound in the detection of vasospasm in patients with aneurysmal subarachnoid hemorrhage: illustrative cases

BACKGROUND Effective management of patients with aneurysmal subarachnoid hemorrhage (aSAH) demands vigilant monitoring and treatment, given the risks of complications such as cerebral vasospasm and delayed ischemic neurological deficits (DINDs). Transcranial transmission ultrasound (TTUS) is a well-established technique for assessing brain pulsatility. This pilot study aims to explore the utility of TTUS in detecting impaired intracerebral blood flow associated with DINDs. OBSERVATIONS The authors examined 2 male patients, ages 45 and 52 years, with aSAH Hunt and Hess grades 4 and 2, respectively, who developed DINDs during their clinical course. Simultaneous recordings of arterial blood pressure, heart rate, and TTUS measurements were obtained in the intensive care unit. TTUS analysis revealed abnormal arrhythmic wave patterns during DIND episodes, whereas baseline measurements on DIND-free days showed no abnormalities. Following endovascular spasmolysis, TTUS demonstrated a normalization of abnormal waves, returning to baseline levels, alongside the resolution of neurological symptoms. LESSONS TTUS, a noninvasive method for assessing brain pulsatility, shows promise as a novel tool for monitoring aSAH patients, potentially aiding in prompt diagnostics and additional therapeutic interventions. Its capacity to provide further insights for individuals at risk of delayed cerebral ischemia warrants further investigation in clinical studies. https://thejns.org/doi/abs/10.3171/CASE24146.