Tinnitus, vertigo and balance disorders in children: Viva

Branch 1: Classifying the vertigo

The candidate should confirm that the first step in a child with dizziness is to establish the quality and the duration of the symptom, because the duration sorts the common benign causes from the dangerous ones. Brief, stereotyped, recurrent episodes lasting seconds to minutes point to the periodic syndromes of childhood, and this girl has the picture of benign paroxysmal vertigo of childhood, the commonest vertigo of a preschool child. A single prolonged attack points to the acute vestibular syndrome, and a constant progressive unsteadiness points to a chronic vestibular hypofunction or a central lesion. The teaching point is that the tempo frames the whole differential before a single test is ordered. [2] [3]

A strong candidate names the peripheral-versus-central split as the second, recurring cut, applied throughout the assessment, because the central causes are the ones that harm the child if missed. The candidate should explain that benign paroxysmal vertigo of childhood is an episodic syndrome that may be associated with migraine, that the family history of migraine supports it, and that a substantial proportion of affected children develop migraine or vestibular migraine later in childhood. [2]

Branch 2: The peripheral-versus-central assessment

If the examiner presses on how to separate a peripheral from a central cause, the candidate should describe the nystagmus examination as the single most informative bedside test. A peripheral vestibular lesion gives a unidirectional horizontal-torsional nystagmus beating away from the affected ear and present in the primary position, while a central lesion gives a direction-changing or a gaze-evoked nystagmus, and a vertical, downbeating or upbeating, nystagmus is a central sign. The head impulse test assesses each horizontal canal and is abnormal toward the affected ear in a peripheral lesion, and the test of skew completes the rule. [7]

The candidate should then state the head impulse, nystagmus, test of skew rule for the acute vestibular syndrome and its high-stakes application. A peripheral cause gives an abnormal head impulse, a unidirectional nystagmus, and no skew, while a central cause gives a normal head impulse, a direction-changing nystagmus, or a skew deviation, and any central sign is an indication for urgent magnetic resonance imaging for a posterior circulation stroke. The rule is more sensitive for stroke than early computed tomography, and its omission is the cardinal error in the acute vestibular syndrome. [3] [7]

Branch 3: The curable positional vertigo

If the examiner introduces a child with brief positional vertigo on rolling over, the candidate should recognise benign paroxysmal positional vertigo and its curative treatment. The Dix-Hallpike manoeuvre elicits the characteristic latent, torsional, upbeating nystagmus that fatigues on repetition, and the posterior canal is most often affected. The candidate should explain that the mechanism is the displacement of otoconia into the canal and that the Epley canalith repositioning manoeuvre moves the otoconia back out of the canal and is curative in a single session in most children. [5]

A strong candidate names the post-traumatic and the post-concussion scenario as the one the examinations test, in which an adolescent develops brief positional vertigo after a head injury. The candidate should explain that benign paroxysmal positional vertigo is an under-recognised and treatable cause of persistent dizziness after a sports-related concussion and that the Epley manoeuvre is as effective in children and adolescents as in adults. The teaching point is that recognising and treating the positional vertigo restores the participation that the persistent dizziness had prevented. [5]

Branch 4: The recurrent vertigo of the school-age child

If the examiner shifts to a school-age child with recurrent vertigo and a family history of migraine, the candidate should diagnose vestibular migraine from the consensus criteria. The criteria require recurrent vertigo lasting five minutes to seventy-two hours, a personal or family history of migraine, and migraine features in at least half of the attacks, and the candidate should explain that vestibular migraine is the commonest cause of recurrent vertigo beyond the preschool years. The diagnosis rests on the consensus criteria rather than on a single test, and the child is normal between the attacks. [1]

The candidate should then defend the management. The first step is lifestyle measures on sleep, hydration, screen time, and the migraine triggers, with reassurance that the vertigo of vestibular migraine shares the triggers and the prognosis of migraine headache. A migraine prophylaxis, such as propranolol, amitriptyline, or topiramate, is added when the episodes are frequent or disabling, following the paediatric migraine guidance. The candidate should also state the role of vestibular rehabilitation in the chronic vestibular hypofunction and the limited, short-course role of the vestibular suppressant in the acute attack alone, because its prolonged use delays the central compensation. [1] [10]