In contemporary practice, neck dissections may be classified into two broad categories based on the therapeutic intent or purpose: elective neck dissection and therapeutic neck dissection. The first widely used classification system was presented in 1991 by the American Society of Head and Neck Surgery and was adopted by the American Academy of Otolaryngology-Head and Neck Surgery; the system was revised in 2002 and clarified in 2008. Selective neck dissection of levels I, II, and III demands understanding the fascial layers enveloping the neck contents and the maneuvers necessary to "unwrap" the muscles to deliver an intact specimen. The steps of radical neck dissection that differ from the selective neck dissection are: the sacrifice of the internal jugular vein, spinal accessory nerve, and sternocleidomastoid muscle (SCM). Application of appropriate traction and countertraction is essential when identifying fascial planes, as it facilitates dissection while minimizing blood loss.
