Transcranial Doppler Ultrasound Applications in Neurology and Neurocritical Care: Literature Review

Aplicações do Ultrassom Doppler Transcraniano na Neurologia e Terapia Intensiva Neurológica: Revisão da Literatura

Abstract

Background: Transcranial Doppler (TCD) has gained increasing evidence in the field of Neurology and Neurointensive Care. It provides real time evidence of cerebral blood flow (CBF) estimated through blood flow velocities (BFV), pulsatility index (PI) and spectral waveform analysis. Its most established applications are the detection of vasospasm in subarachnoid hemorrhage (SAH), stroke prevention in children with sickle cell disease and as a complementary method in brain death diagnosis. TCD can also be used for stroke work-up in detection of cardiac or extra cardiac right-to-left shunts, evaluation of microemboli, intracranial stenosis, vasoreactivity, and as a non-invasive tool of intracranial pressure (ICP) monitoring and cerebral autorregulation. Objectives: We aimed to review the most recent evidence regarding TCD principles, technique and applications, its main advantages and limitations.

Methods: We performed a comprehensive review in literature databases regarding TCD, cerebrovascular diseases work-up and management, besides aids in neurocritical management.

Results: TCD has a strong well-established role in stroke prevention in children with sickle cell disease and in management of vasospasm/delayed cerebral ischemia in SAH. Other indications such as stroke and hemodynamics understanding in critically ill patients have been gaining importance and popularity.

Conclusions: TCD is a useful, safe and feasible tool that can be used in both in and out of hospital scenarios. It is of utmost importance for stroke work-up and prevention. It is gaining increasing evidence as a non-invasive method of estimating intracranial pressure and autorregulation, besides being consecrated as a complementary tool in brain death.