Application study of cerebral blood flow circulation time by contrast-enhanced ultrasound in noninvasive intracranial pressure monitoring / 中华超声影像学杂志

ABSTRACT

Objective:To evaluate the cerebral blood flow circulation time (CCT) by contrast-enhanced ultrasound, and to explore the change rule of CCT in different degree of intracranial pressure, so as to provide a new method for non-invasive monitoring of intracranial pressure.Methods:Ten patients with hemorrhagic stroke or acute craniocerebral trauma with increased intracranial pressure were selected from Tangdu Hospital, the Air Force Military Medical University from January to December 2019. Contrast-enhanced ultrasound was performed when the invasive intracranial pressure (iICP) increased (>20 mmHg, iICP increased group) and decreased to normal (≤20 mmHg, iICP normal group), CCT was measured and analyzed. The differences of CCTs between different iICP groups were compared and the relationship between CCT and iICP was analyzed.Results:①The CCT on the lesion sides of the same patients in the iICP increased group was significantly longer than in the iICP normal group[(9.34±2.58)s vs (6.48±1.91)s, P=0.002]. ②When iICP was increased in patients with hemorrhagic stroke or acute craniocerebral trauma, the CCTs of the diseased side and the non-pathological side were not statistically significant [(9.34±2.58)s vs (9.01±3.22)s, P=0.809]. ③Pearson correlation analysis and Spearman rank correlation analysis showed that there were no correlations between patient′s breathing, heart rate, carbon dioxide partial pressure, body temperature, GCS score and CCT (all P>0.05). Age, mean arterial pressure and CCT were moderately correlated ( r=0.518, 0.463 and P=0.023, 0.046, respectively). ④Logistic regression analysis showed that CCT was an independent risk factor related to intracranial hypertension( OR=0.7, 95% CI=0.47-0.95, P=0.036). The area under ROC curve (AUC) predicted by logistic regression was 0.750(0.588~0.912). Conclusions:Contrast-enhanced ultrasound noninvasive assessment of CCT can reflect the intracranial pressure in patients with hemorrhagic stroke or acute traumatic brain injury, and CCT has a predictive value for intracranial hypertension. When the patient has limited conditions for invasive intracranial pressure monitoring, or when the invasive monitoring probe is pulled out but still needs to evaluate intracranial pressure, the change of CCT can provide an effective reference for clinical diagnosis and treatment.