AN36.1-7 | Mouth, Pharynx & Palate — Gate Quiz

Correct. The parotid duct pierces the buccinator and opens opposite the crown of the upper second molar tooth. This landmark is important in diagnosing parotid duct calculi (sialolithiasis).

Stensen's duct (parotid duct) opens into the vestibule of the mouth opposite the crown of the upper second molar. This is an important clinical landmark — palpate the duct intraorally and look for expressed pus or saliva.

Correct. The uvula deviates AWAY from the side of the lesion (towards the intact side). If the uvula goes right, the RIGHT levator is pulling it — meaning the LEFT levator is paralysed → LEFT-sided CN X lesion.

The uvula deviates to the intact (normal) side — the intact levator veli palatini pulls it toward itself. Uvula to the right = right side is intact = left-sided CN X palsy.

Correct. The tensor veli palatini is supplied by the nerve to medial pterygoid (CN V3), not by CN X. All other palatine muscles (levator veli palatini, palatoglossus, palatopharyngeus, musculus uvulae) are supplied by CN X via the pharyngeal plexus.

Tensor veli palatini = CN V3 (nerve to medial pterygoid). This is the only exception. All other soft palate muscles = CN X via pharyngeal plexus. The tensor opens the Eustachian tube; that is why CN V3 (trigeminal jaw-opening reflex connection) is involved.

Correct. A third pharyngeal pouch (pyriform sinus) fistula opens internally at the apex of the pyriform fossa and tracks through the thyroid gland or paratracheal tissue to the skin of the neck (usually left side, as the left recurrent laryngeal nerve's deeper course makes the left side more prone to these anomalies). It presents as recurrent left-sided neck abscesses exacerbated by upper respiratory infections.

Pyriform sinus fistula = third (or fourth) pharyngeal pouch remnant. It opens internally at the pyriform fossa. Left-sided predominance. Classically presents as recurrent left neck abscesses in children that are exacerbated by upper respiratory infections. Second branchial fistula opens at the tonsillar fossa and emerges along the anterior border of SCM.

Correct. The pharyngeal opening of the Eustachian tube is located on the lateral wall of the nasopharynx (just posterior to the inferior concha). Hypertrophied adenoids (pharyngeal tonsil on the posterior wall/roof) can obstruct this opening → impaired middle ear ventilation → negative middle ear pressure → glue ear (otitis media with effusion) → conductive hearing loss.

The Eustachian tube opens on the lateral wall of the nasopharynx. Adenoids on the posterior wall/roof can grow large enough to obstruct this opening → middle ear cannot equalise pressure → otitis media with effusion (glue ear). This is the most common cause of conductive hearing loss in children in India.

Correct. A pulsatile mass in the tonsillar fossa must NEVER be incised blindly. The ICA lies approximately 2.5 cm lateral to the tonsil, and a tortuous or aneurysmal ICA can bulge medially into the tonsillar fossa, mimicking a quinsy. Inadvertent incision of the ICA is catastrophic. Always palpate first and escalate immediately if pulsation is felt.

A pulsatile tonsillar fossa mass is a vascular emergency, not a quinsy. The internal carotid artery is only 2.5 cm lateral to the tonsil — a tortuous ICA can mimic peritonsillar abscess. Always palpate before incision. Imaging (CT angiogram) is the next step before any intervention.

Correct. Killian's dehiscence lies between the oblique fibres of the thyropharyngeus (upper part of the inferior constrictor) and the horizontal fibres of the cricopharyngeus (lower part = upper oesophageal sphincter). These two parts of the inferior constrictor have different fibre orientations, creating a triangular gap through which Zenker's diverticulum herniates.

Killian's dehiscence = between thyropharyngeus (oblique fibres) and cricopharyngeus (horizontal fibres). Both are parts of the inferior pharyngeal constrictor but have different fibre orientations, creating a posterior weak point. (Laimer-Haeckermann area is between the cricopharyngeus and the oesophageal circular muscle.)

Correct. A Zenker's diverticulum is a pulsion diverticulum with no muscle layer — just mucosa and submucosa. During rigid oesophagoscopy, the scope tends to follow the path of least resistance into the pouch rather than the true oesophageal lumen, and can perforate the thin wall of the diverticulum. This is a well-recognised, potentially fatal complication.

Zenker's diverticulum lies posterior to the pharyngo-oesophageal junction. A rigid oesophagoscope preferentially enters the pouch (which faces the scope) rather than the true oesophageal lumen (which is compressed by the pouch). The thin diverticulum wall (no muscle layer) is easily perforated.

Correct. The palatine tonsils are the most common site of extranodal non-Hodgkin's lymphoma in the head and neck region. They are the largest component of Waldeyer's ring and have the most abundant B-cell-rich lymphoid tissue. A unilateral, rapidly enlarging tonsil in an adult should always raise the suspicion of lymphoma.

Palatine tonsils are the largest and most lymphoid-tissue-rich component of Waldeyer's ring. They are the most common site for extranodal lymphoma in the H&N. A unilateral tonsillar enlargement in an adult (especially without infective features) must be biopsied to exclude lymphoma.

Correct. The internal branch of the superior laryngeal nerve (sensory to the supraglottic larynx) runs in the mucosa/submucosa of the medial wall of the pyriform fossa after piercing the thyrohyoid membrane. A foreign body or instrument in the pyriform fossa is in close proximity to this nerve.

The internal laryngeal nerve (sensory branch of superior laryngeal nerve) runs submucosally in the lateral wall of the pyriform fossa after piercing the thyrohyoid membrane with the superior laryngeal vessels. This is why foreign bodies and instruments in the pyriform fossa can inadvertently injure this nerve.