Lecture on Assessment of the Dizzy Patient

Introduction

• Focus on the assessment of dizzy patients.
• Management and special investigations will be covered separately.
• Goal: Understand how to address dizzy patients and recognize relevant pathologies.

Myths and Misconceptions

• Misconception: Nothing can be done for dizzy patients.
  • Truth: Most can be cured or significantly improved.
• Misconception: Meniere's disease is a common cause of dizziness.
  • Truth: It is an uncommon cause.
• Misconception: Patients with dizziness are ‘mad’.
  • Truth: Many have accompanying anxiety, depression, agoraphobia.

Understanding Balance System

• Balance depends on four sensory inputs:
  1. Vision
  2. Peripheral vestibular system
  3. Proprioception
  4. Hearing
• The brain integrates and interprets these inputs.
• Outputs for balance:
  • Stabilize vision
  • Postural control
  • Spatial awareness

Balance System Mechanisms

• Sensory inputs weighting changes based on situation and sensory input changes.
• Templates in the brain drive balance comparison for dizziness and vertigo.
• Escalator example: Balance adaptation depends on previous experience.

Anatomy of Inner Ear

• Inner ear and peripheral vestibular organ:
  • Three semicircular canals for angular head rotation.
  • Utricle and saccule for static head tilt and linear acceleration.
• Vestibular reflex stabilizes vision through compensatory eye movements.

Clinical Assessment and Diagnosis

• Importance of a detailed history, examination, and special investigations.
• Taking History:
  • Key to understanding dizziness episodes.
  • Focus on the first episode, associated symptoms, mental state, and episode frequency.
• Past medical history, drug history are critical.

Physical Examination

• Observe gait, demeanour, especially as patients enter the clinic.
• Check blood pressure for postural hypotension.
• Perform otoscopy to check for middle ear issues.
• Cranial nerve examination, especially eye movements.

Testing and Diagnosis

• Head Impulse Test:
  • Used for assessing peripheral vestibular hypofunction.
  • Sensitivity varies, but specificity is high.
• Head Shake Test:
  • Provokes nystagmus to assess peripheral hypofunction.
• Dynamic Visual Acuity:
  • Tests ability to read while head is moved.
• Romberg's Test:
  • Test for proprioception and peripheral vestibular function.

Specialized Tests

• Dix-Hallpike Test:
  • Positional test to induce nystagmus.
  • Essential to document nystagmus type for diagnosing BPPV.
• Interpretation of test results critical for diagnosis differentiation (BPPV types, central pathology indicators).

Case Analysis and Management

• Understanding link between different vestibular pathologies.
• Importance of addressing multiple issues for overall patient improvement.

Conclusion

• Comprehensive assessment involves history, examination, and specialized tests for accurate diagnosis.
• Future sessions to cover management and special investigations.

Q&A Highlights

• Importance of vestibular function testing in specific conditions like Meniere’s and vestibular migraine.
• Diagnosing vestibular migraine requires exclusion of other causes, detailed history, and testing.

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These notes summarize the lecture's key points, highlighting the importance of a thorough assessment process in diagnosing and improving the conditions of dizzy patients. The session emphasized detailed history taking, physical examination, and understanding the sensory inputs and outputs involved in balance.