Being guided by the ultrasound is safer for the patient because of the extra assurance of avoiding vital structures. (southernazvets.com)
The many vital structures are very small and tightly pack into the small critical area. (2ndchance.info)
Other vital structures, the axons and dendrites — known collectively as neurites — that project from the nerve cells and send and receive messages are dependent on this neural transport network. (discovermagazine.com)