4 IntroductionHypopharyngeal pouch is an acquired pulsion diverticulum caused by posterior protrusion of mucosa through pre-existing weakness in muscle layers of pharynx or esophagus.In contrast, congenital diverticulum like Meckel's diverticulum is covered by all muscle layers of visceral wall.
12 1. Tonic spasm of cricopharyngeal sphincter: C.N.S. injury Gastro-esophageal reflux2. Lack of inhibition of cricopharyngeal sphincter3. Neuromuscular in-coordination between Thyro-pharyngeus & Cricopharyngeus4. Second swallow against closed cricopharynxThese lead to increased intra-luminal pressure inhypopharynx & mucosa bulges out via weak areas.
14 Entrapment of food in pouch: sensation of food sticking in throat & later dysphagia Regurgitation of entrapped food: leads to foul taste bad odor nocturnal coughing chokingHoarseness: due to spillage laryngitis or sac pressure on recurrent laryngeal nerveWeight loss: due to malnutritionCompressible neck swelling on left side: reduces with a gurgling sound (Boyce sign)
15 Complications Lung aspiration of sac contents Bleeding from sac mucosa Absolute oesophageal obstructionFistula formation into: trachea major blood vesselSquamous cell carcinoma within Zenker diverticulum (0.3% cases)
16 Investigations Chest X-ray: may show sac + air - fluid level Barium swallowBarium swallow with video-fluoroscopyRigid OesophagoscopyFlexible Endoscopic Evaluation of Swallowing
21 Staging Lahey system: Stage I: Small mucosal protrusion Stage II: Definite sac present, but hypo-pharynx& esophagus are in lineStage III: Hypopharynx is in line with pouch& esophagus pushed anteriorly
45 Introduction Normal length of styloid process is 2.0–2.5 cm Length >30 mm in radiography is considered an elongated styloid process5-10% pt with elongated styloid have painIncreased angulation of styloid process both anteriorly & medially, can also cause painCommonly seen in females over 40 years.
46 HistoryWatt Weems Eagle described this in 1937 with 200 cases. 2 types: classical & carotid artery syndrome
47 Classical Variety Occurs several years after tonsillectomy Pharyngeal foreign body sensationDysphagiaDull pharyngeal pain on swallowing, rotation of neck or protrusion of tongueReferred otalgiaDue to scar tissue in tonsillar fossa engulfing branches of glossopharyngeal nerve
48 Carotid Artery Syndrome Carotid artery compression by styloid process presents as carotodynia, headache & dizzinessHistory of head or neck trauma presentExternal carotid artery involvement: neck pain, radiates to eye, ear, mandible, palate & noseInternal carotid artery involvement: parietal headaches & pain along ophthalmic artery
51 Theories for ossification Reactive hyperplasia: trauma ossification of fibro-cartilaginous remnants in stylohyoid ligamentReactive metaplasia: abnormal post-traumatic healing initiates calcification of stylohyoid ligamentLoss of elasticity of stylohyoid ligament: AgeingAnatomic variance: ossification of stylohyoid ligament is an anatomical variation without trauma
52 Theories for pain Irritation of glossopharyngeal nerve Irritation of sympathetic nerve plexus around internal carotid arteryInflammation of stylo-hyoid ligamentStretching of overlying pharyngeal mucosa
53 DiagnosisDigital palpation of styloid process in tonsillar fossa elicits similar painRelief of pain with injection of 2% Xylocaine solution into tonsillar fossaX-ray neck lateral viewOrtho-pan-tomogram (O.P.G.)Coronal C.T. scan skull3-D reconstruction of C.T. scan skull
60 Intra-oral route via tonsil fossa no external scarring poor visibility due to difficult accesshigh risk of damage to internal carotid arteryiatrogenic glossopharyngeal nerve injuryhigh risk of deep neck space infection
63 Styloidectomy Tonsillectomy done. Styloid process palpated. Incision made in tonsillar fossa just over the tip.Styloid attachments elevated till its base with periosteal elevator.Styloid process broken near its base with bone nibbler, avoiding injury to glossopharyngeal nv.Tonsillar fossa incision closed.
64 Extra-oral routeIncision extends from mastoid process along sternocleidomastoid to level of hyoid then across neck up to midline of chinexternal scar presentbetter exposureless morbidity