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EN2.1-12 | Core ENT Clinical Skills — PBL Case

CLINICAL SETTING

It is a Monday afternoon in a busy district hospital ENT OPD. Dr Kavitha, a final-year MBBS student posted for her ENT clinical attachment, is with her supervising registrar. The first patient is Mr Rajan, a 42-year-old government clerk, who slides into the chair and immediately says: 'Doctor, I have been using cotton buds to clean my ears every evening for the past two years. But last week, one side got completely blocked and now I cannot hear properly on that side. And my wife says I keep talking too loudly.' Dr Kavitha is told to take a full ENT history and prepare for examination. The registrar steps out to take a phone call, leaving her with the patient — and the full set of ENT instruments on the trolley. Mr Rajan also mentions that six months ago he had a cold that lasted a week, and since then his left ear has 'felt full'. He denies ear discharge, earache, or vertigo. He has no history of noise exposure or family history of hearing problems.

Trigger 1: History, Tuning Forks, and the Registrar's Test

Dr Kavitha elicits the following: **History:** Left ear fullness since the cold 6 months ago. Bilateral hearing reduction ('right is better than left'). No discharge, no pain, no vertigo, no tinnitus. Significant cotton bud use bilaterally — 'I insert them deep to clean'. Occupation: quiet office environment. No noise exposure. Non-smoker. The registrar returns and hands her a 512 Hz tuning fork. 'Do Rinne and Weber,' he says. She performs them and records: - **Rinne Left:** Fork placed on left mastoid — heard for 18 seconds. Fork in front of left ear — heard for 10 seconds. (BC > AC) - **Rinne Right:** Fork on right mastoid — heard for 10 seconds. Fork in front of right ear — heard for 22 seconds. (AC > BC) - **Weber:** Fork on forehead — patient says 'I hear it louder on the LEFT side.' The registrar asks: 'What is your interpretation? And is there any trap you should be aware of when interpreting Rinne positive on the right?'

DISCUSSION POINTS

  • Interpret each tuning-fork result: what does left Rinne negative indicate? What does Weber lateralising to the LEFT mean in this context? Is the right Rinne positive reassuring or could it be misleading?
  • The registrar mentions 'false Rinne negative' — explain the clinical scenario where a Rinne positive result on one side may actually indicate severe ipsilateral SNHL with bone conduction perceived through the contralateral cochlea (the false Rinne negative trap). How does this change the overall interpretation?
  • Based on the history and tuning-fork findings alone, what is your differential diagnosis? List in order of probability and give one distinguishing feature for each.
  • What does Mr Rajan's pattern of cotton bud use suggest as a contributing or causative factor? Which part of the ear is most at risk from deep cotton bud insertion?
Click to reveal Trigger 2: The Otoscope and the Audiogram (discuss previous trigger first!)

Trigger 2: The Otoscope and the Audiogram

Dr Kavitha performs otoscopy under supervision. For the LEFT ear: she straightens the ear canal by gently pulling the pinna upward, backward and slightly outward. Through the otoscope: **Left TM finding:** Dull, amber/yellowish appearance. Loss of the normal 'cone of light'. Malleus handle prominent and retracted. TM immobile on pneumatic otoscopy. No perforation seen. No wax impaction. **Right TM finding:** Normal translucent appearance. Cone of light intact. Mobile TM on pneumatic pressure. The registrar then shows her the pure tone audiogram arranged by the audiology technician: - **Left ear:** AC 45 dB at all frequencies; BC 22 dB - **Right ear:** AC 18 dB; BC 15 dB - **Tympanogram:** Left = Type B flat curve; Right = Type A The registrar asks: 'Calculate the air-bone gap, name the type of hearing loss, and explain what the Type B tympanogram means.'

DISCUSSION POINTS

  • Describe the four main landmarks of the tympanic membrane that Dr Kavitha should document. Based on the otoscopy findings, which landmarks are abnormal and why? Represent this as a labelled diagram description.
  • Calculate the left ear air-bone gap. Does the audiogram confirm conductive, SNHL, or mixed hearing loss? Justify your answer using both the air-bone gap and the BC threshold value.
  • What does a Type B tympanogram (flat curve, absent peak) indicate about middle ear status? How does this integrate with the otoscopic findings and history to confirm the diagnosis?
  • The registrar asks Dr Kavitha to document the TM finding in the case notes 'as if drawing a diagram'. Describe how you would represent the abnormal left TM appearance diagrammatically, naming the quadrant landmarks and indicating the abnormal features.
Click to reveal Trigger 3: Consent, Investigation Selection, and an Unexpected Emergency (discuss previous trigger first!)

Trigger 3: Consent, Investigation Selection, and an Unexpected Emergency

The diagnosis is confirmed: **left otitis media with effusion (glue ear)**. The ENT registrar explains that Mr Rajan needs myringotomy and ventilation tube (grommet) insertion under local anaesthesia in clinic. Dr Kavitha is asked to counsel Mr Rajan and obtain informed consent. Mr Rajan is apprehensive: 'Will this make my hearing worse? What if something goes wrong?' Midway through the consent counselling, an emergency call arrives from the resuscitation bay: a 50-year-old patient with bilateral peritonsillar abscess has developed rapidly progressive oropharyngeal swelling. The anaesthesiologist has failed three attempts at oral intubation. The anaesthesiologist calls the ENT registrar: 'We need an airway — now.' The registrar says to Dr Kavitha: 'Stay here, explain to Mr Rajan why I have left, but also — what airway procedure would I perform now, and where exactly on the neck? And what if this were being planned electively tomorrow morning — what would change?'

DISCUSSION POINTS

  • Complete the informed consent counselling for myringotomy: what are the (i) indication, (ii) nature of the procedure, (iii) TWO most important material risks to disclose, and (iv) the alternative management option? How would you frame the risk of ossicular injury for a patient?
  • The registrar asks which radiological, microbiological, or histological investigation — beyond the audiogram — would be MOST useful if the left ear had shown a foul-smelling discharge and marginal perforation instead of a flat amber TM. Name the investigation and explain the CSOM safe vs unsafe distinction that would change the investigation priority.
  • For the emergency in the resus bay: name the CORRECT procedure (not tracheostomy) and its exact anatomical site. Explain, in physiological and anatomical terms, why this is faster and more reliable in an acute 'cannot intubate, cannot oxygenate' situation than an emergency tracheostomy.
  • If the same patient's airway procedure were being planned electively under theatre conditions, what would change — name the procedure, its anatomical level, and explain why the choice shifts from the emergency option.

Group Task Assignments

Group 1: Tuning-Fork Mastery and Audiogram Interpretation

  • Create a table summarising the expected Rinne and Weber results for: (a) normal hearing, (b) unilateral conductive hearing loss, (c) unilateral SNHL, (d) bilateral SNHL
  • Explain the 'false Rinne negative' trap (false-negative Rinne negative = Rinne positive in severe ipsilateral SNHL with cross-hearing through contralateral cochlea) with a worked clinical example
  • Draw a PTA grid and plot the audiogram findings from Trigger 2; calculate and label the left air-bone gap

Competencies: EN2.3, EN2.4

Group 2: Otoscopy Technique and TM Documentation

  • Write a step-by-step otoscopy checklist for a final-year student, covering: patient positioning, canal straightening (adult vs child), instrument hold, three sequential examination targets, and TM landmark description
  • Draw and label a tympanic membrane diagram marking: handle of malleus, umbo, pars tensa, pars flaccida (Shrapnell's membrane), anteroinferior quadrant (safe myringotomy site), and light reflex cone
  • Describe how the abnormal TM findings in Trigger 2 differ from a normal TM at each landmark

Competencies: EN2.2, EN2.5

Group 3: Investigation Selection and CSOM Safe vs Unsafe

  • For glue ear (otitis media with effusion): list the investigations in the order you would request them and justify each choice
  • Contrast the investigation pathway for CSOM 'safe' (tubotympanic) type vs 'unsafe' (atticoantral) type — name the key investigation that changes and explain why cholesteatoma-associated disease requires it
  • Name two ENT conditions where a CT scan is mandatory before any other intervention, and explain the clinical reasoning

Competencies: EN2.6, EN2.8

Group 4: Consent Counselling and National Prevention Programmes

  • Draft a patient-readable informed consent summary for myringotomy + grommet insertion — cover indication, procedure, four material risks, and alternative
  • The NPPCD (National Programme for Prevention and Control of Deafness) targets four age groups. Map the correct hearing screening modality to each age group (neonate, school-age, adult, elderly) and name the programme component responsible
  • Mr Rajan's cotton bud use caused his condition. Write a 100-word patient education note for him explaining why cotton buds are harmful, what the normal self-cleaning mechanism of the ear canal is, and what he should do instead

Competencies: EN2.9, EN2.12

Group 5: Emergency Airway and ENT Topical Medications

  • Create a comparison table: Cricothyroidotomy vs Tracheostomy — anatomical site, type of case (emergency vs elective), technique in brief, key complication to avoid for each
  • For the peritonsillar abscess emergency in Trigger 3: outline the complete 'cannot intubate, cannot oxygenate' (CICO) management algorithm, positioning the ENT procedure within the WHO Difficult Airway Algorithm steps
  • Describe the correct technique for instilling ear drops in a patient with a suspected intact tympanic membrane (EN2.11): patient positioning, number of drops, gentle tragal pumping rationale, duration of maintained position, and when instillation is contraindicated

Competencies: EN2.10, EN2.11

Learning Issues

Research these questions and bring your findings to the discussion.

  1. [EN2.3] What are the tuning-fork tests used in ENT? For each test (Rinne, Weber, Schwabach, Bing, Gelle's), describe the technique, normal result, and what each abnormal pattern indicates — including the false Rinne negative trap.
  2. [EN2.4] How do you interpret a pure tone audiogram? Define: threshold, air conduction, bone conduction, air-bone gap. What are the audiometric patterns of conductive, SNHL, and mixed hearing loss? What is a Type B vs Type A vs Type C tympanogram?
  3. [EN2.2] Describe the complete headlamp-based ENT examination workflow: patient positioning for ear/nose/throat examination, technique of ear canal straightening in adults vs children, use of nasal speculum, indirect laryngoscopy technique, and elicitation of laryngeal crepitus.
  4. [EN2.5] What are the four quadrants of the tympanic membrane? Name the key landmarks in each quadrant. What is the significance of the pars flaccida (Shrapnell's membrane) in CSOM? What TM findings suggest otitis media with effusion?
  5. [EN2.9] What are the four elements of valid informed consent? For myringotomy and grommet insertion, what are the material risks and alternatives? What specific ENT procedures require consent under EN2.9 (list: tympanoplasty, mastoidectomy, FESS, septoplasty, tracheostomy, adenotonsillectomy)?
  6. [EN2.10] What is the emergency airway of choice in a 'cannot intubate, cannot oxygenate' scenario? Describe the anatomy of the cricothyroid membrane. What are the contraindications to aural syringing for foreign body removal? How do you manage a live insect in the ear canal?
  7. [EN2.12] Describe the NPPCD: its goals, target age groups, screening modalities (OAE, AABR, free-field audiometry), and the role of the ENT surgeon in community deafness prevention. What is 'World Hearing Day' and its significance?