ASSESSMENT OF NEUROLIGAL SYSTEM

• NEUROLOGICAL ASSESSMENT
• 12 CRANIAL NERVES & THEIR FUNCTIONS

  • I. OLFACTORY
  • II. OPTIC
  • III. OCULOMOTOR
  • IV. TROCHLEAR
  • V. TRIGEMINAL
  • VI. ABDUCENS
  • VII. FACIAL
  • VIII. ACOUSTIC / VESTIBULOCOCHLEAR
  • IX. GLOSSOPHARYNGEAL
  • X. VAGUS
  • XI. SPINAL ACCESSORY
  • XII. HYPOGLOSSAL
• Cranial Nerve I: OLFACTORY

  Type of impulse: Sensory

  Function: Carries smell impulses from nasal mucous membrane
• Cranial Nerve II: OPTIC

  Type of impulse: Sensory

  Function: Carries visual impulses from eye to brain (visual acuity, visual fields, fundoscopic exam)
• Cranial Nerve III: OCULOMOTOR

  Type of impulse: Motor

  Function: Contracts eye muscles to control eye movements (interior lateral, medial and superior), constricts pupils, and elevates eyelids
• Cranial Nerve IV: TROCHLEAR

  Type of impulse: Motor

  Function: Contracts one eye muscle to control inferomedial eye movement
• Cranial Nerve V: TRIGEMINAL


  Type of impulse: Sensory / Motor

  Function: Carries sensory impulses of pain, touch and temperature from the face to the brain. Influences clenching and lateral jaw movements (biting, chewing)
• Cranial Nerve VI: ABDUCENS

  Type of impulse: Motor

  Function: Controls lateral eye movements
• Cranial Nerve VII: FACIAL

  Type of impulse: Sensory / Motor

  Sensory: Taste, anterior ⅔ of tongue. Stimulates secretions from salivary glands and tears from lacrimal glands.

  Motor: Facial movement and expressions
• Cranial Nerve VIII: ACOUSTIC / VESTIBULOCOCHLEAR

  Type of impulse: Sensory

  Function: Contains sensory fibers for hearing and balance
• Cranial Nerve IX: GLOSSOPHARYNGEAL


  Type of impulse: Sensory / Motor

  Sensory: Taste, posterior ⅓ of tongue. Sensory fibers of the pharynx that result in the gag reflex.

  Motor: Provides secretory fibers to parotid salivary glands and promotes swallowing movements
• Cranial Nerve X: VAGUS

  Type of impulse: Sensory / Motor

  Function: Carries sensations from the throat, larynx, heart, lungs, bronchi, gastrointestinal tract, and abdominal viscera. Promotes swallowing, talking and production of digestive juices
• Cranial Nerve XI: SPINAL ACCESSORY

  Type of impulse: Motor

  Function: Innervates neck muscles (sternocleidomastoid and trapezius) that promote movement of the shoulders and head rotation. Promotes some movement of the larynx
• Cranial Nerve XII: HYPOGLOSSAL

  Type of impulse: Motor

  Function: Innervates tongue muscles that promote the movement of food and talking
• ASSESSMENT PROPER
• CN I - OLFACTORY NERVE

  Have client sit in a comfortable position at your eye level

  Ask the client to clear the nose to remove any mucus

  Close eyes, occlude one nostril, and identify a scented object that you are holding such as soap, coffee, or vanilla

  Repeat procedure for the other nostril
• Normal (CN I - Olfactory Nerve)


  Client correctly identifies scent presented to each nostril

  Some older clients' sense of smell may be decreased
• Deviations from normal (CN I - Olfactory Nerve)


  Neurogenic Anosmia (inability to smell or identify the correct scent) may indicate olfactory tract lesion, frontal lobe tumor, congenital, nasal or sinus problems, nerve tissue injury, smoking and use of cocaine
• CN II - OPTIC

  Use snellen chart to assess vision in each eye

  Ask the client to read a newspaper or magazine paragraph to assess near vision

  Assess visual fields of each eye by confrontation

  Use an ophthalmoscope to view the retina and optic disc of each eye
• Visual Acuity (Normal)


  Client has 20/20 vision OD (right eye) and OS (left eye) - (distance vision)
• Visual Acuity (Deviations from normal)

  Difficulty reading Snellen chart, missing letters, squinting
• Near Vision (Normal)


  Reads print at 14 inches without difficulty (until the patient is in the late 30s to the late 40s)
• Near Vision (Deviations from normal)


  Reads print by holding closer than 14 inches or holds print farther away as in presbyopia, which occurs with aging
• Visual Fields (Normal)


  Normal peripheral vision
• Visual Fields (Deviations from normal)


  Loss of visual fields may be seen in retinal damage or detachment, lesions of the optic nerve, lesions of the parietal cortex
• Retina & Optic Disc by Ophthalmoscope (Normal)


  Optic Disc: 1.5 mm, round or slightly oval, well-defined margins, creamy pink with paler physiologic cup

  Retina: pink
• Retina & Optic Disc by Ophthalmoscope (Deviations from normal)

  Papilledema, optic atrophy
• CN III, IV, VI - OCULOMOTOR, TROCHLEAR, ABDUCENS

  Inspect margins of the eyelids of each eye

  Assess extraocular movements

  Assess pupillary response to light (direct and indirect) and accommodation in both eyes
• Normal (CN III, IV, VI)

  Eyelid covers about 2 mm of the iris

  Eyes move in a smooth, coordinated motion in all directions (the six cardinal fields)

  Bilateral illuminated pupils constrict simultaneously

  Pupil opposite the one illuminated constricts simultaneously
• Deviations from normal (CN III, IV, VI)


  Ptosis (drooping of the eyelid) is seen with weak eye muscles (myasthenia gravis)

  Abnormal eye movements may be caused by cerebellar disorders, increased ICP, paralytic strabismus

  Pupil abnormalities may be caused by oculomotor nerve paralysis, Argyll Robertson pupils, narcotics abuse, CN III damage, lesions of the sympathetic nervous system, PNS or CNS dysfunction, CN V lesion
• CN V - TRIGEMINAL

  Test motor function: Ask the client to clench the teeth while you palpate the temporal and masseter muscles for contraction

  Test sensory function: Touch the forehead, cheeks, and chin with sharp or dull stimuli and light touch, and ask the client to identify

  Test corneal reflex: Lightly touch the cornea with a fine wisp of cotton and observe the eyelid blink
• Motor function (Normal - CN V)

  Temporal and masseter muscles contract bilaterally
• Motor function (Deviations from normal - CN V)


  Decreased contraction in one or both sides, asymmetric strength in moving the jaw may be seen with lesion or injury of the 5th cranial nerve, pain occurs with clenching of the teeth
• Sensory function (Normal - CN V)

  Correctly identifies sharp and dull stimuli and light touch to the forehead, cheeks, and chin
• Sensory function (Deviations from normal - CN V)


  Inability to feel and correctly identify facial stimuli, lesions of the trigeminal nerve, lesions in the spinothalamic tract or posterior columns
• Corneal reflex (Normal - CN V)

  Eyelids blink bilaterally
• Corneal reflex (Deviations from normal - CN V)


  Absent corneal reflex, lesions of the trigeminal nerve, lesions of the motor part of cranial nerve VII (facial)
• CN VII - FACIAL

  Test motor function: Smile, frown and wrinkle forehead, show teeth, puff out cheeks, purse lips, raise eyebrows, close eyes tightly against resistance

  Test sensory function: Touch the anterior two thirds of the tongue with a moistened applicator dipped in salt, sugar, or lemon juice and ask the client to identify the flavor
• Motor function (Normal - CN VII)


  Smiles, frowns, wrinkles forehead, shows teeth, puffs out cheeks, purses lips, raises eyebrows, and closes eyes against resistance. Movements are symmetric.
• Motor function (Deviations from normal - CN VII)


  Inability to close eyes, wrinkle forehead, or raise forehead along with paralysis of the lower part of the face on the affected side (Bell's Palsy). Paralysis of the lower part of the face on the opposite side affected may be seen with a central lesion that affects the upper motor neurons (Stroke).