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The Dizzy Patient 4x4 Method Dr Ahmad Alamadi FRCS Consultant, HOD Al Baraha Hospital Vestibular Physiology Orientation of our body in space is the primary function of the vestibular system. This is achieved by integration of signals from vestibular, visual and proprioceptive receptors at the level of brain stem. Information regarding the movement of the head relative to the body is largely provided by paired vestibular sensory endorgans Vestibular Sensory Endorgans Cristae & Otolithic organ Information Relay Peripheral Vestibular System EYES Proprioceptive Receptors Central Vestibular Nuclei Vestibulocerebellar tracts (VCT) Vestibulo-Ocular reflex (VOR) Vestibulospinal (VST) VOR Keeps a stable retinal image during head movement As the head moves in one direction there should be an equal and opposite conjugate movement of the eyes (sometime known as the doll’s eye maneuver) VOR Defect Bilateral Defect : (for example from systemic aminoglycoside toxicity) the patient will complain of imbalance and a blurring of vision with head movement better known as oscillopsia Unilateral defect : the equilibrium of the push-pull forces between the inner ears is altered. This result in a drift of the eyes away from side of lesion followed by a quick central nervous system (CNS) mediated saccade in a repetitive to and fro fashion better known as nystagmus. Nystagmus is the cardinal sign of a central or peripheral vestibular disorder History Steps 1. Organic Vs Psychogenic 2. Vestibular Vs Non vestibular 3. Peripheral Vs Central 4. Which Peripheral Vestibular Disorder Organic Vs Psychogenic Features Organic vestibular Psychogenic Duration Usually well defined i.e. seconds, minutes or hours (never a “flash”) Variable from a “flash” to days Not well defined Frequency Except for benign paroxysmal positional vertigo (BPPV), rarely more than once a day Constant or many times a day Head Movement Intensifies symptoms Symptoms usually unaffected Ataxia during spell Usually prominent Insignificant Effect of Hyperventilation Not like the attack Often reproduces symptoms accurately Vestibular Vs Non vestibular True Vertigo (hallucination of movement relative to self) Vs Non specific Dizziness Note patient with non specific dizziness need to be investigated for cardiac and neurological causes. Patients with true vertigo have a vestibular disease which can be central or peripheral Peripheral Vs Central Ask for associated symptoms i.e. discharge, tinnitus, aural fullness and hearing loss Ask for focal neurological complaints i.e. diplopia, dysphagia, dysarthria, paresis, parasthesia or incontinence and LOC. Inner ear disorders should never be associated with a loss of consciousness Which Peripheral Vestibular Disorder Benign paroxysmal positional vertigo (BPPV) seconds; several attacks /day; positional Meniere's disease minutes to hours; tinnitus; fluctuating hearing loss; aural fullness Recurrent Vestibulopathy minutes to hours Vestibular Neuronitis (acute viral labyrinthitis) Hours to days Examination Steps 1. Otological examination 2. Neurological examination 3. Special clinical vestibular tests 4. Important Diagnostic Tests Otological examination Otoscopy Hearing assessment (Weber and Rinne tests) Fistula Test Neurological examination Cranial Nerves Cerebellar Tests Oculomotor Tests Smooth pursuit, saccades, visual fixation and vergence Balance Tests proprioception, Romberg’s and tandem gait tests (both eyes open and closed). When Smooth Pursuit is Normal it would be unlikely for a central disorder to be present Special clinical vestibular tests The Halmagyi maneuver The head shake test The oscillopsia test VOR suppression test Important Diagnostic Tests Dix-Hallpike Positional Test Hyperventilation Test Conclusion 4 steps in History x = 4 steps in Examination 99% Diagnosis Soon on DVD and Internet Interactive Multimedia Textbook of Otology www.otologytextbook.com Thank You