🗣️ Laryngology & Pharyngology
Tonsil blood supply, quinsy, tongue innervation, pharyngeal pouch, tracheostomy anatomy, and the tracheo-innominate fistula — the MRCS pharynx and larynx essentials.
Tonsils & Quinsy (Peritonsillar Abscess)
Palatine Tonsil — Anatomy & Blood Supply
The palatine tonsils lie in the tonsillar fossae between the palatoglossal arch (anterior pillar) and palatopharyngeal arch (posterior pillar). They are part of Waldeyer’s ring of lymphoid tissue (palatine, lingual, pharyngeal/adenoid, and tubal tonsils). They have no afferent lymphatics — antigen exposure is direct through the crypt epithelium.
| Vessel | Supply/Drainage | Clinical Relevance |
|---|---|---|
| Tonsillar branch of facial artery | Primary arterial supply — enters inferior pole of tonsil via superior pharyngeal constrictor | Main bleeding risk during tonsillectomy. The facial artery itself lies close to the lower pole — must stay within the capsule to avoid it. |
| Ascending palatine artery | Branch of facial artery — upper pole | Secondary arterial supply |
| Ascending pharyngeal artery | Branch of ECA — posterior supply | Rarely significant in tonsillectomy |
| Dorsal lingual artery | Branch of lingual artery — inferior | At risk if dissection strays too medially at lower pole |
| Lesser palatine artery | Branch of internal maxillary — superior | Upper pole supply; less clinically significant |
| External palatine (paratonsillar) vein | Venous drainage — descends lateral to tonsil | Most common source of troublesome post-tonsillectomy bleeding — descends from soft palate lateral to the tonsillar capsule. Primary haemostasis vessel to secure during tonsillectomy. |
Ascending palatine (facial artery branch)
Lingual artery (dorsal lingual branch)
Pharyngeal — ascending pharyngeal
Descending — lesser palatine (internal maxillary)
Venous: External palatine (paratonsillar) vein = most common source of post-tonsillectomy haemorrhage
Tonsillectomy — Indications & Complications
SIGN Criteria for Tonsillectomy (Scottish Intercollegiate Guidelines Network)
- Sore throats due to tonsillitis
- ≥5 episodes per year for 2 consecutive years
- Episodes are disabling and prevent normal functioning
- Other indications: obstructive sleep apnoea (OSA), peritonsillar abscess (quinsy — controversial), suspected malignancy (asymmetric tonsil), recurrent febrile convulsions
Post-Tonsillectomy Haemorrhage
| Type | Timing | Cause | Management |
|---|---|---|---|
| Primary | Within 24 hours (intraoperative or immediate post-op) | Inadequate haemostasis intraoperatively — missed vessel, slipped ligature | Return to theatre urgently. Secure airway (blood in pharynx = difficult airway). Direct pressure, bipolar diathermy, ties. |
| Reactionary | 24 hours post-op | Blood pressure rises as anaesthesia wears off → slipped clot | As above — usually return to theatre |
| Secondary | 5–10 days post-op (peak day 5–7) | Sloughing of fibrinous eschar → exposed vessel + secondary infection | Most common. Admit, IV antibiotics (secondary infection), correct coagulopathy. If significant: return to theatre. IV tranexamic acid if brisk. Most settle conservatively. |
Post-Tonsillectomy Haemorrhage — Airway First
A bleeding post-tonsillectomy patient presents an extremely challenging airway — blood in the pharynx, tissue oedema, and a potentially anxious/uncooperative patient. Immediately: sit upright and lean forward (to reduce aspiration risk), establish IV access, cross-match blood. Senior anaesthetist and ENT surgeon must be present for any return to theatre. Rapid sequence induction is standard. Have surgical airway equipment available. Blood in the stomach = high aspiration risk on induction.
Quinsy (Peritonsillar Abscess)
Quinsy is a collection of pus in the peritonsillar space — between the tonsillar capsule and the superior pharyngeal constrictor muscle. It is a complication of acute tonsillitis (group A Streptococcus most commonly, but often polymicrobial including anaerobes). It is the most common deep space infection of the head and neck.
| Feature | Details |
|---|---|
| Symptoms | Severe unilateral sore throat, odynophagia (painful swallowing), trismus (inability to open mouth — pterygoid spasm), drooling (unable to swallow saliva), “hot potato voice” (muffled, as if talking with hot potato in mouth), otalgia (referred via CN IX), malaise, fever |
| Signs | Uvula deviated away from the affected side (pushed by the peritonsillar bulge). Bulging of soft palate and anterior pillar on affected side. Erythematous, oedematous peritonsillar tissues. Ipsilateral cervical lymphadenopathy. |
| Trismus | Caused by spasm of the medial pterygoid muscle (adjacent to the peritonsillar space) — limits mouth opening. Makes examination and drainage challenging. |
| Investigations | Clinical diagnosis. Throat swab. FBC, CRP. Monospot test (Epstein-Barr virus — infectious mononucleosis can present identically with peritonsillar oedema, NOT true abscess — never incise a mono quinsy). USS/CT if diagnosis uncertain or parapharyngeal spread suspected. |
| Management | Incision and drainage (I&D) — needle aspiration (preferred first-line, less traumatic, can be done in clinic) OR formal incision (scalpel at superior pole of tonsil, medial to anterior pillar). IV co-amoxiclav + metronidazole. Analgesia. IV fluids if unable to swallow. Interval tonsillectomy in 6 weeks (UK practice — reduces recurrence; immediate “quinsy tonsillectomy” practiced in some centres). |
| Complications | Parapharyngeal abscess → Lemierre’s syndrome (IJV thrombophlebitis). Airway obstruction. Aspiration of abscess contents. Mediastinitis (via parapharyngeal spread). Erosion into carotid artery (rare — catastrophic). |
Uvula Deviation — Which Way?
In quinsy, the peritonsillar bulge pushes the soft palate medially and superiorly on the affected side, displacing the uvula away from the side of the abscess (towards the unaffected side). This is the opposite of what students often expect. Memory aid: the uvula runs away from the problem side. Contrast with: central neurological lesions affecting the vagus nerve (CN X) — the uvula deviates towards the side of the lesion (healthy side pulls harder).