Eco-color Doppler examination.

<p>Craniocaudal scans performed with transverse planes of the upper and middle third of the mouse neck. <b>(A)</b> At the level of the upper third of the neck the external carotid artery runs anteriorly. <b>(B-D)</b> At level of middle third of the neck arterial and venous vessels are detectable. <b>(B)</b> The blood flow of anterior jugular veins is directed toward the external jugular veins. <b>(C-D)</b> The internal jugular veins are thin and in the typical position, anteriorly and laterally to the carotid artery.