Updated Information for Neuro-anesthesia：The Indication of Transcranial Doppler and Transcranial Color Flow Imaging for Neuro-anesthesia and Intensive Care

Abstract

Transcranial Doppler（TCD）and transcranial color flow imaging（TCCFI）can measure intracranial arterial blood flow velocity using low-frequency ultrasound（2 MHz）. TCCFI but not TCD can roughly image the brain structure using B mode. In addition, TCCFI can visualize blood flow in the anterior cerebral artery, middle cerebral artery, internal carotid artery, and posterior cerebral artery using color mode and can measure blood flow velocity using Doppler mode with angle correction. Both TCD and TCCFI can evaluate cerebral autoregulation and carbon dioxide reactivity as well as changes in cerebral blood flow velocity in response to changes in pathological conditions such as cerebral vasospasm and increased intracranial pressure. Although TCD and TCCFI are not widely used in Japan, noninvasive bedside monitoring using these modalities can provide abundant information for treatment of patients.