The High Yield Neurologic Examination • Mental Status-Brief Review • Cranial Nerves – Common/Urgent Patterns John Engstrom, M.D

Overview – The Neurologic Examination The High Yield Neurologic Examination • Mental status-brief review • Cranial nerves – common/urgent patterns John Engstrom, M.D. • Motor exam – common/urgent patterns April 2017 • Sensory exam – common/urgent patterns • Selective demonstrations

Q1: Which statement regarding the Screening Mental Status mental status exam is false? 1) Attention span (immediate recall) is not • Orientation-time, place, person abnormal in patients with dementia • Attention-Digit span forward (nl > 6-7) 2) Language testing is a screen for aphasia • Language-repetition, naming, comprehension 3) If recent memory testing is abnormal, then • Memory-Recall of 3 common objects at 5 attention is probably also abnormal minutes; if misses an answer give a prompt 4) Abstractions are often abnormal in the setting of dementia • Abstractions-Similarities and differences (e.g.-apple vs. orange; lake vs. river) 5) Attention span is often abnormal in late dementia

1 Assessment of Vision Screening for Visual Field Deficits

• Measure acuity with glasses on/contacts in • Allows you to test function of broad areas of brain • Establishing a visual field cut establishes a – Lobes-occipital, temporal, parietal – Optic nerves, chiasm, thalamus structural lesion (eye vs. brain) • Clinical Importance • The pupils always react in cortical blindness – “An anatomic sedimentation rate of the brain” – Afferent-retina, optic nerve/tract, brainstem – Detect abnormalities that require brain imaging – Efferent-midbrain, third nerve, ciliary muscle – Localize the deficit (right vs. left brain)

Screening for Visual Field Deficits- Ambulatory, Cooperative Patient • Imagine visual field cut in four equal pieces • Move examiner finger in the center of each quadrant with patient gaze fixed • Test each eye by covering the opposite eye, present stimulus in center of all 4 quadrants • Describe the deficit in terms of the portion of the visual field affected

2 Q2: What causes sustained dilation Cranial Nerve Exam-Pupils of a pupil in response to a light? • Anatomic pathways-afferent CN II, 1) Afferent pupillary defect midbrain, efferent bilat parasymp in CN III 2) Hippus – Best tested dim light; Est size before/after light 3) Efferent pupillary defect – Assess baseline symmetry of shape and size 4) Stroke affecting the parietal lobe – Assess direct and consensual response 5) Stroke affecting the occipital lobe – No other part of the nervous system affected! • Abnormalities may be in CN II or III

Common Pupillary Exam Patterns

• Common False Positives – Mydriatic drugs (unilateral if topical); child – Inadequacy of light stimulus (use bright light against a dim background) – Post surgical-cataracts, prosthetic eye • Afferent pupil defect-Light stimulus doesn’t reach brainstem due to diseased CN II – Pupil dilates despite constant light stimulus – Examples-multiple sclerosis, meningioma

3 Urgent Outpatient Pupillary Exam Pattern • Exclude false positives • History/exam suggest intracranial process? • Efferent pupil dilated unilaterally (6-9 mm) – Accompanied by CN III palsy (eye down/out) – Greater than 1 mm asymmetry – Compression of CN III by temporal lobe brain tissue displaced from a mass – Consider urgent brain MRI or head CT

What Cranial Nerves Have in Common Cranial Nerves III, IV, and VI

• Brainstem portion-many other brainstem • Movements-eye out is VI, eye down and in findings present (e.g.-MS, tumor) is IV, everything else is III • Subarachnoid space-CN and nerve roots – Move finger in horizontal and vertical planes pass through the CSF after exit cord – Move finger in and down bilaterally-IVth – Often multiple CN involved • Monocular diplopia – Example-infectious/carcinomatous meningitis, – Pt cover one eye; is only one image remaining? • Skull base-inside/outside skull to target – Strongly consider ordering brain MRI to cover tissue innervated (e.g.-motor/sensory) brainstem, skull base, and orbit

4 Cranial Nerve VII-Muscles of Q3: What facial movement is normal in Facial Expression upper motor neuron weakness? • Upper 1/3-Furrowing the eyebrows

1) Smile • Middle 1/3-Eye closure-can test power by 2) Eye closure forcing eyes open against resistance 3) Eyebrow furrowing • Lower 1/3-Smile 4) Lower 2/3 of face • All three affected-Lower motor neuron 5) Upper 2/3 of face facial paresis (e.g.-Bell’s palsy) • Lower 2/3 affected-upper motor neuron (brain or upper brainstem)

CN VII-Utility of Testing CN VII-Examination • Lower 2/3 face-MRI of brain • Upper 1/3-furrowing brow, symmetry • Entire face-Bell’s palsy • Middle 1/3-degree eye closure, symmetry – LMN VII only finding – Power testing-force eyelids open using thumbs- one each at upper and lower orbit – Acute onset; stabilize/improve over days-weeks – With effort, globe rotates upward-see sclera • Apparent Bell’s but CNS location (e.g.-MS, – Lack of effort, globe motionless-see iris + pupil brain tumor) • Lower 1/3-excursion of smile, symmetry – Other neurol symptoms/signs – Coincident medical illness (e.g.-meningitis)

5 CN V, VIII, X, XI

• CN V-test three divisions of face with pin or light touch • CN VIII-finger rub next to each ear; audiogram if questionable • CN X-uvula elevation in the midline • CN XI-symmetry/power of shoulder shrug

CN XII-Tongue Motor Exam • Two muscles fused midline; separate CNs • Bulk-smooth lateral contour, symmetry • Bulk-place the contour of the muscle on a • Power screen-tongue protrusion midline nl perpendicular to your line of vision • Grading power-hold tongue-in-cheek vs. • Tone-move limb passively across a joint resistance slowly and rapidly • Dysarthria-slurred speech due to weakness • Power-grade 1-5 on the MRC scale – Lips (labial dysarthria) • Reflexes-grade 0-4 – Tongue (lingual dysarthria) • Gaits-Demonstration at the end of talk – Palate (nasal dysarthria)

6 The Weak Patient: The Symptom of Weakness Pertinent History Temporal sequence • Patients mean a functional limitation of Functional activities motor activity SOB • Confused with: – fatigue Ambulation-independent vs. cane vs. walker – depression (“neurasthenia”) vs. wheelchair – decreased sensation Stand up/reach overhead-proximal muscles – decreased force moving a painful limb Stand on toes; use pen/spoon-distal muscles Complete motor exam-not power alone

Breakaway Weakness is Not Examination Signs of True Weakness True Weakness

• Reduced but constant resistance when • DEFINITION: Variable resistance by the testing the power a muscle on clinical patient during muscle power testing examination • ASSOCIATED WITH PAIN: Cannot • There are only two types of true weakness: determine if underlying weakness present – Central: brain, brainstem, cord • UNASSOCIATED WITH PAIN: Poor effort – Peripheral: anterior horn cell, root, plexus, or attention nerve, neuromuscular junction, muscle

7 Weak Patient: History and Examination Q4: Which statement is FALSE re/ clinical utility of distinguishing UMN from LMN weakness on exam?

1) Informs decision to obtain imaging NEUROLOGIC NON-NEUROLOGIC 2) Informs the decision of what part of the nervous system to image UPPER MOTOR LOWER MOTOR FATIGUE BREAKAWAY NEURON NEURON 3) Determines need for neuromuscular referral

POOR EFFORT 4) Helps determine differential diagnosis PAIN 5) None of the above statements is false

Weak Patient: Central Weakness I Weak Patient: Central Weakness II

Power -  distal > proximal in limbs Spasticity-velocity-dependent increase in tone  extensors > flexors in arms to passive stretch of a limb that is greatest in the  dorsiflexors > plantar flexors in legs flexors of the arms and extensors of the legs  lower 2/3 of face (if from brain injury) -Rapid, repetitive movements are slow in the Bulk - Normal fingers and feet; dominant side normally faster Tone - spastic; Babinski sign(s) present -Pronator drift-pronation the essential finding; may also flex the fingers and drop the arm Reflexes - 

8 Motor Exam-Grading Power Motor Exam-The Challenge of

SCORE RESPONSE Grading Power 5 Full power • Most weakness is between 4 and 5 4+/5- Minimal weakness • Inter-examiner variability 4 Mild weakness • What do you do with the weight-lifter? 4- Moderate weakness • Qualitative scale: mild, moderate, severe? 3 Severely weak; able to move vs. gravity • Pattern weakness usually more informative 2 Moves, but not against gravity than attempt to exactly quantify weakness 1 Flicker of contraction 0 No muscle contraction

Motor Examination-Common Traps Motor Exam-Grading Reflexes

• Focal atrophy from disuse or pain with use SCORE RESPONSE • Tongue fasciculations-all tongues twitch 4 Clonus • Apparent increased tone from patient 3 Hyperactive inability to relax during the exam 2 Normoactive • Nocturnal headaches can be caused by CO2 1 Hypoactive retention during sleep in NM resp failure Trace Present with reinforcement only 0Absent

9 Q5: Which answer is an inadequate Weak Patient-Lower Motor explanation for an absent DTR? Neuron Weakness 1) Inadequate stretch on tendon being struck • All features of true weakness on exam 2) Contracture of the tendon • Patterns of weakness and other findings 3) Vinca alkaloid use (e.g.-vincristine) determine the differential diagnosis 4) Muscle weakness – Distal polyneuropathy-weakness first in distal 5) Absence of muscle tissue attached to the legs with sensory loss and absent ankle reflexes tendon being struck – Myopathy-proximal weakness in arms and legs without sensory loss or reflex changes – Global new areflexia-always needs explanation

CNS Sensory Loss (2 Cs) and PNS Sensory Loss (2 Ps) Sensory Examination • Central-Circumferential limb/trunk distrib. • Light touch-tests primarily large diameter – Distribution belong to many nerves/nerve roots nerve fibers and CNS sensory pathways – Cord, brainstem, brain – Easy to test with finger or Q-tip • Peripheral-Patchy distribution over a limb – Can use over entire body – In nerve or root distribution – Can use VAS (0-10) for semi-quantitation – Distribution belongs to single nerve/nerve root – Change in quantity or quality of light touch? • Exception: stocking-glove sensory loss of a • Pin sensation tests small diameter nerve distal sensory polyneuropathy fibers and CNS pain pathways-sharp or dull

10 Demonstrations-A Volunteer? Gait-Hemiparetic

• CNs-facial strength, tongue • Affected leg is stiff and circumducts during • Motor exam walking – Tone-normal, rigidity, spasticity • Affected arm is partially flexed in a spastic – Power-proximal and distal limb muscles position – Reflexes-triceps, finger flexors, ankles • Gait-What is wrong with my walking?

Gait-Alcoholic Cerebellar Gait-Parkinsonian Degeneration • Short small shuffling steps bilaterally • Affects the truncal balance center in the • En-bloc turning-multiple steps to turn midline cerebellum around instead of the normal two steps • Limb coordination is fine • Reduced arm wing-unilateral or bilateral • Typical gait is wide-based • Retropulsion-tendency to fall backwards • Cannot tandem walk when standing still and given a minor push • Classic presentation-no distal sensory loss

11 Gait-Steppage Gait-Sensory Ataxia

• Due to foot drop of any cause • Lack to sensation in the feet of any cause • To avoid tripping over the toes during the • Nearly all patients have a Romberg sign foot drop, the patient compensates by lifting • Inability to tell position of feet in space the proximal leg high in the air results in imbalance • High risk of falls; socially embarrassing – Visual compensation is gone in darkness • Correctable with ankle-foot orthosis (brace) (washing hair with eyes closed while standing) – Wide-based gait accompanied by sensory loss

Conclusions

• A good screening neurologic exam can be performed in 10 minutes • Additional neurologic examination will be dictated by the history and initial examination findings • The disease context and pattern of neurologic findings is most helpful, not a single finding

John Engstrom, M.D. April 2017 +

The HNeurological Examination

Mental Status Examination Before beginning the mental status examination, assess education level and native language of the patient. The results of the exam must be interpreted in the context of these factors. 1. Orientation –You will have an excellent indicator of orientation simply by interviewing the patient. To test formally, ask for the patient's name, the date (as day, month, year), and where the patient is located now. 2. Attention span –Test attention span (immediate recall) by having the patient repeat a numerical sequence. A patient should be able normally to recall 7-8 digits forward; The likelihood of normal recent recall at 5 minutes is low if attention span is impaired. Almost everyone must remember a numerical sequence (e.g.-telephone number). 3. Recent recall – Ask the patient to remember 3 items and repeat them back after 5 minutes. This test is best performed if the objects to be remembered are familiar to the patient. For example, one might ask a carpenter to remember a hammer, a board, and a house. You should always ask the patient to repeat all 3 items immediately back to you first to make sure the patient understands each item. 4. Repetition, naming, and comprehension – The inability to produce language (aphasia) can be tested efficiently. A sentence can be repeated such as, “Today is a sunny day”. Naming can be performed with 3 common objects such as a pencil, tie, shoe, or belt. Objects should be easily identifiable and appropriate to the cultural background and educational level of the patient. Comprehension is tested throughout the examination history and by the ability of the patient to follow directions and answer questions. 5. Abstractions – Abstractions are complex, difficult tasks for a cognitively impaired patient. Examples: “What is the difference between a cat and a dog?” “How would you distinguish between a lake and a river?” or “How are a lake and river alike?” The answers may be abnormal in patients with either delerium or dementia. 6. Speech –Speech can be placed under the mental status or cranial nerve examinations. Abnormalities of speech (dysarthria) can be related to cranial nerve abnormalities including VII (labial dysarthria), X (palatal dysarthria), or XII (lingual dysarthria). 7. Neglect- Can the patient distinguish between the right and left side of the body or pay attention to the left and right side of the room (name objects to the right or left) 8. The above guidelines are for a screening mental status examination. There are many different formats for the mental status examination that can be adapted to specific circumstances.

Cranial Nerve Examination If in doubt about whether or not a cranial nerve finding is abnormal, check for symmetry between the two sides.

II – Vision – Screen corrected (i.e.- with glasses) visual acuity with a vision card. Allow the patient to hold the card. Screen for major visual field deficits by having the patient cover one eye and identify an object (often a finger) in the center of each visual quadrant of each eye.

II, III – Pupillary examination – Normal size in moderate light for adults is 3-4 mm. Normally larger in children and smaller in the elderly (“senile miosis”). Acceptable asymmetry is ≤ 1 mm.

Page 1 Check both direct and consensual reactions. For patients with a dark pigmented iris, try using a second flashlight held from below or above the face to illuminate the pupils without causing constriction.

III, IV, VI – Extraocular movements. Check horizontal, vertical, and inferonasal (down and in) eye movements. Can the patient move the eyes from side-to-side fully so as to eliminate the sclera from view? Nystagmus is a rapid, beating movement of the eyes – (usually in a horizontal plane) that is triggered by eye movement. Remember that VI controls abduction and IV controls inferonasal movement. III controls all other eye movements.

V – Corneal response, facial sensation. Use a wisp of cotton and lightly touch the cotton to the surface of each cornea. Note if both the direct and consensual corneal responses are present. Check pin and light touch sensation on each cheek.

VII – Facial expression – Test the muscles of facial expression by having the patient raise the eyebrows, close the eyes tightly, and smile. Note any asymmetry in the extent of facial movement and speed of movement on the two sides of the face.

VIII – Hearing – Rub the fingers together by each ear so that the fingers can normally be heard, but no movement of the fingers or arms seen by the patient. Vestibular function is screened during testing of the extraocular movements by noting the presence or absence of nystagmus. A few beats of nystagmus at the extremes of horizontal eye movement is normal. Direction of the nystagmus (by convention) named for fast component of the beating eye movements. Vertical gaze nystagmus is almost always due to a posterior fossa (cerebellum or brainstem) lesion

IX, X – Soft palate function – Gag reflex, nasal voice, elevation of the palate. Elevation of the palate is the best screening test. The uvula normally elevates in the midline when the patient says 'Ahhhhhhhl" A nasal voice is an indication of soft palate dysfunction. Gag reflex is helpful when asymmetric, but uncomfortable for patients; may be bilaterally absent in some normal or elderly patients.

XI –Trapezius–If you need to test this cranial nerve, do so with the trapezius muscles (bilateral shoulder shrug against resistance-both sides tested simultaneously).

XII – Tongue – Note the bulk of the two sides of the tongue when protruded. If the tongue is weak from a XIIth nerve lesion, it will protrude toward the side of the lesion. Strength can be tested by having the patient push the tongue against the inside of each cheek. In the presence of facial weakness, one can think tongue appears tomprotrude to one side. Line up position of the tongue with tip of the nose and middle of chin to determine if tongue protrudes to one side.

The Motor Examination 1. If in doubt about whether or not a finding (bulk, power, reflexes) is abnormal, check for symmetry between the two limbs. 2. A screening examination will include sampling of the proximal and distal muscles of the arms and legs. In otherwise healthy patients, the ability to perform a deep-knee bend is a good screen of proximal leg power. 3. You cannot perform an adequate muscle examination unless you can see the muscles! The patient must be positioned and dressed appropriately. 4. You will not remember the innervation and action of all the muscles. You may want to get a portable book with diagrams that can serve as an instant resource (i.e.-Aids to the Examination of the Peripheral Nervous System).

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Bulk – Check the bulk of the deltoid, abductor pollicis brevis (APB), and quadriceps muscles. Visually compare the same muscles on the right with the left limbs. Tone – Move the limbs slowly and quickly through their range of motion with the patient relaxed and supine. Increased tone consists of abnormal resistance to passive movement of the limbs, despite adequate relaxation and the absence of pain during the movement. Spasticity is a velocity-dependant increase in resistance that is greatest in the flexors of the arms and extensors of the legs. Power – For a screening exam, check one proximal and one distal arm muscle (biceps and first dorsal interosseus muscles are good choices in the arms). Check one proximal and one distal leg muscle: iliopsoas and tibialis anterior are good choices. Alternatively, screen the proximal muscles of the legs by having the patient perform a deep-knee bend. Coordination – Check finger-to-nose and heel-knee-shin on both sides. Check tandem gait by having the patient walk while placing the toe of one foot to the heel of the opposite foot repetitively. Tell the patient that it is an accuracy test, not a speed test! The patient can use laterally outstretched arms for balance while walking and should keep their eyes open. Correct results for patient age; tandem gait normally begins to “normally” deteriorate over age 60. Check for fast finger movements by having the patient tap the first finger and thumb in a rhythmic and rapid fashion. Asymmetric, slow, but rhythmic fast finger movements or foot tapping is a sensitive test for an upper motor neuron lesion. Check for pronator drift by having the patient extend outstretched arms fully forward with the palms up and close the eyes. The patient is instructed to hold the arms steady. The hand of a weak arm in an upper motor neuron lesion (i.e. – a stroke) will pronate, flex, and tend to drift downward. Gait – Many neurologic problems may be subtle until a patient attempts to walk. Walking can be difficult for the hospitalized patient due to pain, instrumentation, or extreme fatigue. Can the patient independently bear weight on both legs? Can the patient independently maintain balance while standing? Do the legs move symmetrically when walking? These questions can be answered when a patient stands and takes just a few steps at the bedside. Specific gait disorders (i.e. – spastic, parkinsonian, steppage, and elaboration) for inpatents able to ambulate will be demonstrated. Reflexes – The limbs to be tested should be relaxed and in a comparable position bilaterally if interpretation of the results is to be valid. Always check for symmetry. The most common cause of an unobtainable ankle reflex is improper positioning of the foot! Your reflex screen should include the biceps, triceps, finger flexors, quadriceps, and ankle reflexes. For the neuroanatomy of each reflex, consult your handout. Check for a Babinski response by first lightly stroking the lateral aspect and ball of the foot from back to front with the stick of a Q-tip. You can use a more vigorous stimulus if a response is initially absent. A normal response is plantar flexion of the toes. A Babinski response consists of dorsiflexion of the great toe.

The Sensory Examination “The sensory examination almost kept me out of the field of neurology” – Robert A. Fishman, MD, former Professor and Chairman, UCSF Neurology.

The sensory examination should ideally include small fiber modalities (pain or temperature) and large fiber (light touch, vibration, position) modalities because disease may selectively involve one or the other. When neuropathy is present, both are most commonly inovled.

Light touch – Use a cotton swab or fingertip to check for asymmetry of touch sensation or a proximal-to-distal gradient below the knees. If the patient has a subjective complaint of diminished sensation, compare sensation on the affected patch of skin with an analogous patch of skin on the opposite limb. Define normal touch as 10 (on a scale of 0-10) and complete absence of touch as 0. Ask the patient to assign a number to the “amount of touch” always

Page 3 beginning with demonstration of normal sensation as 10. Reduction of touch sensation below 7 strongly suggests decreased sensation.

Pin – Use a safety pin and lightly touch the patient asking if a sharp sensation can be felt. Check one spot on each hand and foot. Check from proximal-to-distal below the knees to see if perception of the sharpness declines. An increase in sensitivity from proximal to distal can be normal, but a decrease is abnormal.

Romberg – The patient stands with the feet together as closely as possible. First verify that balance is maintained with the eyes open, then ask the patient to close the eyes. The most common cause of a “false positive” test is failure to perform this first step. If the patient cannot maintain balance when the eyes are closed, then a Romberg sign is present. The Romberg sign is a sensory test of large fiber sensation, not a cerebellar test of coordination.

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Neurologic Examination-References

1. Ropper AH, Samuels, MA, Kline JP. Principles of Neurology, 10th ed. New York: McGraw Hill, 2014.

2. Brazis PW, Masdeu JC, Biller J. Localization in Clinical Neurology, 7th ed. Philadelphia:Wolters-Kluwer, 2017. 3. Lin VW, Cardenas DD, Cutter NC et al. Spinal Cord Medicine. New York: Demos, 2003. 4. Daroff RB, Mazziotta JC, Pomeroy SL, and Jankovic J. Neurology in Clinical Practice. Philadelphia:Elsevier, 2015. 5. Stewart JD. Focal Peripheral Neuropathies, 3rd ed. Philadelphia: Lippincott Williams and Wilkins, 2013. 6. O’Brien M. Aids to the Examination of the Peripheral Nervous System, 5th ed. New York: Saunders-Elsevier, 2010. My favorites above are in bold

Question Answer Key

Q1-selection 1

Q2-selection 1

Q3-selection 3

Q4-selection 5

Q5-selection 4

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