Killian's dehisence is seen in:

Ans. C Cricopharynx Ref. Scott Brown's lth/ed Vol 2 Chapter 155 p 2045; Dhingra 5th/ed p 253, 6th/ed p 238 Killian's Dehiscence (Fig. 8.6) it is an area of weakness between the two pas of inferior constrictor muscle-sub thyropharyngeus and cricopha-ryngeus A pulsion diveiculum of pharyngeal mucosa can emerge posteriorly through the Killian's dehiscence called as Zenker's diveiculum or pharyngeal pouch. Since it is an area of weakness it is one of the sites of esophageal perforation during instrumentation and scopy-hence also called 'Gateway of Tears