16.1 Overview of the Neurological Exam

The neurological exam is a crucial tool for assessing brain function. It checks mental status, cranial nerves, motor skills, sensory perception, and reflexes. This comprehensive evaluation helps doctors pinpoint issues in specific brain regions and their associated functions.

In emergencies, quick neurological assessments are vital. They help identify deficits rapidly, guiding treatment decisions and monitoring patient progress. Understanding common causes of neurological problems, like strokes or injuries, aids in prompt diagnosis and effective care.

Components and Importance of the Neurological Exam

Components of neurological exam

Top images from around the web for Components of neurological exam

• 

  Overview of the Neurological Exam · Anatomy and Physiology View original

  Is this image relevant?

• 

  The Sensory and Motor Exams · Anatomy and Physiology View original

  Is this image relevant?

• 

  Clinical Techniques: The Neurological Assessment – A Mixed Course-Based Research Approach to ... View original

  Is this image relevant?

• 

  Overview of the Neurological Exam · Anatomy and Physiology View original

  Is this image relevant?

• 

  The Sensory and Motor Exams · Anatomy and Physiology View original

  Is this image relevant?

1 of 3

Top images from around the web for Components of neurological exam

• 

  Overview of the Neurological Exam · Anatomy and Physiology View original

  Is this image relevant?

• 

  The Sensory and Motor Exams · Anatomy and Physiology View original

  Is this image relevant?

• 

  Clinical Techniques: The Neurological Assessment – A Mixed Course-Based Research Approach to ... View original

  Is this image relevant?

• 

  Overview of the Neurological Exam · Anatomy and Physiology View original

  Is this image relevant?

• 

  The Sensory and Motor Exams · Anatomy and Physiology View original

  Is this image relevant?

1 of 3

• Mental status assessment evaluates patient's level of consciousness (alert, responsive), orientation to person, place, and time, and memory and cognitive function (attention, language, problem-solving)
• Cranial nerve examination tests function of all 12 cranial nerves including olfactory (I) for smell, optic (II) for vision, oculomotor (III), trochlear (IV), abducens (VI) for eye movements, trigeminal (V) for facial sensation and jaw movement, facial (VII) for facial expressions, vestibulocochlear (VIII) for hearing and balance, glossopharyngeal (IX) and vagus (X) for swallowing and taste, spinal accessory (XI) for neck and shoulder movement, and hypoglossal (XII) for tongue movement
• Motor system examination assesses muscle strength and tone (resistance to passive movement), coordination and balance (finger-to-nose, heel-to-shin tests), and gait and posture (walking, standing)
• Sensory system examination tests various sensory modalities such as touch (light touch, pressure), pain (pinprick), temperature (cold, warm), vibration (tuning fork), and proprioception (joint position sense)
• Reflexes are tested including deep tendon reflexes (knee jerk, ankle jerk), superficial reflexes (abdominal, plantar), and pathological reflexes indicating neurological abnormalities (Babinski sign, clonus)

Brain regions and functions

• Frontal lobe responsible for executive functions, planning, decision-making, and motor control and speech production in Broca's area
• Parietal lobe processes and integrates sensory information and is involved in spatial awareness and navigation
• Temporal lobe handles auditory processing and language comprehension in Wernicke's area and is crucial for memory formation and retrieval
• Occipital lobe primarily involved in visual processing and perception
• Cerebellum coordinates and fine-tunes motor movements and maintains balance
• Brainstem regulates vital functions like breathing, heart rate, blood pressure and is essential for arousal and maintaining consciousness

Rapid assessments in emergencies

• Rapid identification of neurological deficits allows for timely intervention and treatment to prevent further damage
• Triage and prioritization of care based on severity of condition and need for immediate action
• Quick assessments guide further diagnostic testing (CT, MRI) and management decisions
• Monitoring patient's neurological status over time enables detection of deterioration or improvement
• Neurological localization helps identify the specific area of the nervous system affected by the injury or disease

Neurological Deficits and Ischemic Events

Causes of neurological deficits

• Stroke caused by disruption of blood supply to the brain, either ischemic (blockage) or hemorrhagic (bleeding)
• Traumatic brain injury resulting from external force or rapid acceleration/deceleration of the head
• Infections of the nervous system such as meningitis (inflammation of meninges) or encephalitis (inflammation of brain tissue)
• Neurodegenerative disorders characterized by progressive loss of neurons and cognitive decline, including Alzheimer's disease, Parkinson's disease, and multiple sclerosis
• Brain tumors, both benign and malignant, can compress or invade surrounding brain tissue
• Metabolic disorders like hypoglycemia (low blood sugar) or electrolyte imbalances can disrupt normal neurological function
• Toxins and substance abuse can directly damage neurons or alter neurotransmitter levels

Types of ischemic events

1. Transient ischemic attack (TIA)
   • Brief, reversible neurological deficit lasting less than 24 hours
   • Symptoms resolve completely but indicate high risk for future stroke
2. Ischemic stroke
   • Prolonged neurological deficit lasting more than 24 hours due to blocked blood supply
   • Can lead to permanent brain damage and disability if not promptly treated
3. Cerebral venous sinus thrombosis (CVST)
   • Clot formation in the venous sinuses draining blood from the brain
   • Causes increased intracranial pressure and various neurological symptoms
   • Requires prompt diagnosis and anticoagulation therapy to prevent complications

Neurological Protection and Adaptation

• The blood-brain barrier selectively filters substances entering the brain, protecting it from harmful agents in the bloodstream
• Cerebrospinal fluid cushions the brain and spinal cord, providing mechanical protection and helping to maintain a stable environment
• Neuroplasticity allows the brain to adapt and reorganize in response to injury or learning, enabling recovery of function after neurological damage
• Neurotransmitters play a crucial role in communication between neurons and can be targeted by medications to treat various neurological disorders