Basic Anatomy with TCCD and Vessels

Abstract

Brain anatomy can be explored with ultrasonography at the patient’s bedside. Anatomy of the brain vasculature has been described through several acoustic windows: the temporal, the transorbital, the transforaminal, and the submandibular windows. Each window offers the possibility to image specific parts of major basal intracranial arteries as well as cerebral deep veins and sinuses. In daily clinical practice, bilateral examination of the entire circle of Willis can be easily done through the temporal window. Recognition of the different basal arteries is based on their relationship with typical brain structures such as brain peduncles and the direction of their flow to the ultrasound probe. Beyond simple identification of brain vasculature, transcranial color duplex Doppler (TCCD) may also provide useful information regarding brain structures. Using this acoustic window, clinician can explore the entire circle of Willis but also visualize typical brain structures such as the brainstem, and lateral and third ventricles. Potential clinical implications are the assessment of ventricle enlargement and midline shift, and the follow-up of brain hematomas. Emergent evidence suggests that ultrasonographic assessment of these clinical features is well correlated with CT scan, providing a bedside evaluation of brain anatomy. In this chapter, we describe brain anatomy though the different acoustic windows. Two different parts are developed: the first one deals with brain vasculature description and the second one describes brain structures that are imaged through the transtemporal window.