Carotid sheath sternum. The four major structures contained in the carotid sheath are: The carotid artery lies medial to the internal jugular vein, and the vagus nerve is situated posteriorly between the two vessels. In the upper part, the carotid sheath also contains the glossopharyngeal nerve (IX), the accessory nerve (XI), and the hypoglossal nerve (XII), which pierce the fascia of the carotid sheath. The ansa cervicalis is embedded in the anterior wall of sheath. It is formed by "descendens hypoglossi" (C1) and "descendens cervicalis" (C2-C3). The three major fascial layers in the neck contribute to the carotid sheath: the investing fascia,
Interlobular arteries From each glomerulus, the corresponding efferent arteriole arises and then exits the capsule near the point where the afferent arteriole enters. Distally, efferent arterioles branch out to form dense plexuses (i.e., capillary beds) around their adjacent renal tubules. For cortical nephrons, a single network of capillaries, known as the peritubular capillaries, surrounds the entire renal tubule, whereas for juxtamedullary nephrons, the peritubular capillaries surround only the proximal and distal convoluted tubules, while another network branching from the efferent arteriole, known as the straight arterioles of kidney, surrounds the nephron loop (of Henle). Interlobular arteries Interlobular arteries (or cortical radiate arteries