Part I: Neurological Exam Part II: Coma Connie Chen Neurology Consultants of Dallas

Part I Neurological Exam

Neurological Exam: Some Basics Purpose of exam: differential diagnosis Purpose of exam: differential diagnosis The mantra: The mantra: –History comes first! –Exam is next best option. –“Pan-scanning” is a poor substitute for exam. –“Pan-scanning” results in “missing the boat”.

Neurological Exam: More Basics Lecture goal: Lecture goal: –Moving past medical school --see the forests, not the trees. –Tailor your exam to meet your needs. –Full neurological exams will waste your time?

Case example 65 yo with low back pain. 65 yo with low back pain. Pain radiates down right leg. Pain radiates down right leg. He notes new acute weakness in right leg. He notes new acute weakness in right leg. Differential? Differential? How can the exam support/aid in diagnosis? How can the exam support/aid in diagnosis?

Exam Purpose Identify the part of the “neuro-axis” involved: Identify the part of the “neuro-axis” involved: –link EXAM with FUNCTION Neuro-axis: Neuro-axis: –Cortex –Subcortex –Brain stem –Spinal cord –Nerve root –Peripheral nerve –Neuromuscular junction –Muscle.

The Exam Itself Components: Components: –Mental status –CN –Motor (tone, bulk, strength) –Sensation (soft touch/temp/pinprick vs vib/proprio) –Reflexes –Coordination –Gait (stressed gaits, base, arm swing, turn)

Matching Exam to Location –Mental status –CN –Motor –Sensation –Reflexes –Coordination –Gait –Cortex –Subcortex –Brain stem –Spinal cord –Nerve root –Peripheral nerve –Neuromuscular junction –Muscle

Exam Mental status Mental status –Level of alertness –Orientation –Language (naming, fluency, repetition, comprehension, reading) –Calculations –Memory –Judgement/insight –Executive function/Abstract thought –Visualspacial ability Cortex (Frontal, parietal, temporal, occipital) Cortex (Frontal, parietal, temporal, occipital) Subcortex (white matter, thalamus) Subcortex (white matter, thalamus)

Exam Cranial Nerves Cranial Nerves –III/IV –IV-VIII –V, IX-XII Brainstem Brainstem –midbrain –pons –medulla

Motor Exam PATTERNS: Corticospinal tract: strength “stroke pattern” Corticospinal tract: strength “stroke pattern” –tone and bulk change later –spinal cord: spinal shock Anterior horn: weakness at level, fasciculation Anterior horn: weakness at level, fasciculation Root: weakness in all muscles involving root Root: weakness in all muscles involving root Nerve: weakness in all muscles involving nerve Nerve: weakness in all muscles involving nerve Muscle: proximal > distal weakness Muscle: proximal > distal weakness 0= no movement, 1= f licker, 2= gravity removed, 3= against gravity, 4-/4/4+ = grades of resistance, 5= full

Sensation Exam Notoriously painful for all involved. Notoriously painful for all involved. Patterns: Central, cord, peripheral Patterns: Central, cord, peripheral Main pointers: Main pointers: –Dorsal columns: late cross, vib/proprio –Spinal thalamic tract: early cross, ST/temp/PP

Reflexes 0: absent 0: absent 1: present with distraction 1: present with distraction 2: present without distraction 2: present without distraction 3: spreads across more than one joint 3: spreads across more than one joint 4: Clonus- sustained and non-sustained. 4: Clonus- sustained and non-sustained.PATTERNS: Up: Cortical, spinal (before anterior horn) Up: Cortical, spinal (before anterior horn) Down: Root, (nerve, muscle) Down: Root, (nerve, muscle)

Coordination=Cerebellum Rapid alternating movements (dysdiadokinesia) Rapid alternating movements (dysdiadokinesia) Past pointing Past pointing Dysmetria: finger nose/heel to shin Dysmetria: finger nose/heel to shin ??romberg-- not really ??romberg-- not really Wide based stance Wide based stance (nystagmus at primary gaze) (nystagmus at primary gaze) ***Pre-existing weakness can fool you ***Pre-existing weakness can fool you

Gait The best part of exam The best part of exam Evaluates strength, coordination, sensation Evaluates strength, coordination, sensation look at arm swing, base of stance, steps, turn, look at arm swing, base of stance, steps, turn, stressed gaits will bring out subtleties. stressed gaits will bring out subtleties.

Case Revisited 65 yo with low back pain. 65 yo with low back pain. Pain radiates down right leg. Pain radiates down right leg. He notes new acute weakness in right leg. He notes new acute weakness in right leg. Differential? Differential? Exam expectations? Exam expectations?

Case Series 67 yo fell off of a horse and has developed bilateral LE weakness over the course of days. 67 yo fell off of a horse and has developed bilateral LE weakness over the course of days. Differential? Differential? Exam findings? Exam findings? What other pertinent HPI questions would have helped? What other pertinent HPI questions would have helped?

Case series 25 yo notes water feels “funny” on right hand, and then his right leg felt strange. 25 yo notes water feels “funny” on right hand, and then his right leg felt strange. Differential? Differential? Exam findings? Exam findings?

Case Series 40 yo notes left face and arm feels funny since last night and notes left arm and leg weakness. 40 yo notes left face and arm feels funny since last night and notes left arm and leg weakness. Differential? Differential? Exam findings? Exam findings?

Case Series 78yo fell and couldn’t get up. “I knew I was going to get stuck [on the floor] for weeks now.” Why is he weak? 78yo fell and couldn’t get up. “I knew I was going to get stuck [on the floor] for weeks now.” Why is he weak? Differential? Differential? Exam findings? Exam findings?

Case Series 26 yo notes stumbling when walking and an inability to make his jump shots with basketball over the course of 2 days. His toes tingle. 26 yo notes stumbling when walking and an inability to make his jump shots with basketball over the course of 2 days. His toes tingle. Differential? Differential? Exam findings? Exam findings?

Case series 74 yo wm notes left face and arm weakness that lasts only 30 minutes. Later that day she develops vertigo, slurred speech, and diplopia. She can’t walk because she feels “like I’m drunk.” She has right carotid stenosis. 74 yo wm notes left face and arm weakness that lasts only 30 minutes. Later that day she develops vertigo, slurred speech, and diplopia. She can’t walk because she feels “like I’m drunk.” She has right carotid stenosis. Differential? Differential? Exam findings? Exam findings? Right carotid stenosis relevance? Right carotid stenosis relevance?

Part II: Coma

Coma Definition State of sustained unconsciousness State of sustained unconsciousness Ascertained by exam Ascertained by exam

How Coma Happens Structural causes: Structural causes: –Bilateral supratentorial disruption –Disruption of the RAS of the brainstem Practical thoughts (linking history, exam, and structure): Practical thoughts (linking history, exam, and structure): –“metabolic”causes affect brain globally –“Vascular” causes are not equal: unilateral carotid artery vs. vertebral artery vs. basilar artery.

Coma Prognostication Gauging coma: Gauging coma: –History –Exam –Ancillary studies History cannot accurately predict outcome of coma. History cannot accurately predict outcome of coma.

Coma Prognostication Ancillary studies cannot accurately ascertain coma emergence Ancillary studies cannot accurately ascertain coma emergence Exception: Exception: –SSEP’s performed days 1-3 after coma. –Absence of cortical response shows poor prognosis.

Coma Prognosis Exam Exam –Glascow coma score (eye opening, motor response, verbal response) rather useless rather useless –Motor: Command>purposeful>flexor>extensor>flaccid –Cranial nerves: present>absent –Roving eye movements > no spontaneous

Coma Prognosis: Take Home (it’s bad when…) First 24hr post circulatory arrest: myoclonus status epilepticus First 24hr post circulatory arrest: myoclonus status epilepticus Or by day 3: Or by day 3: –no corneals, or –absent pupillary reaction, or –motor response is extensor or worse