The cricopharyngeal raphe is the posterior midline fibrous structure connecting the two sides of the cricopharyngeus muscle (upper esophageal sphincter) where they meet posterior to the pharyngoesophageal junction. Unlike the thyropharyngeus above it (which has a distinct posterior midline raphe), the cricopharyngeus meets in the midline as a direct muscular commissure with a thin fibrous raphe. Killian's dehiscence is the triangular area of weakness between the oblique thyropharyngeus and horizontal cricopharyngeus just above this raphe.
The cricopharyngeal raphe and the adjacent Killian's dehiscence are the anatomical target of flexible endoscopic esophagoscopy-guided Zenker diverticulum treatment (EndoFLIP or rigid endoscopy with stapler): the common wall between the diverticulum and the oesophageal lumen, composed of the cricopharyngeus, is divided (cricopharyngeal myotomy) endoscopically. In open surgery, the raphe is approached posteriorly via an incision lateral to the sternocleidomastoid and the cricopharyngeus is divided in its posterolateral wall under direct vision.
The cricopharyngeal raphe and common wall between the Zenker diverticulum and the oesophageal lumen are divided by rigid endoscopic linear stapler or flexible endoscopic needle-knife myotomy, releasing the obstruction caused by cricopharyngeal dysfunction and allowing the diverticulum to drain freely into the oesophageal lumen.
