Approach to the Patient with Neurologic Disease

Neuroscience ModuleYear Level 7 SY 2010-2011

Neurologic Method

Step 1 : Locate the Lesion

“where is the lesion?”

Step 2 : Define the pathophysiology

“what is the lesion?”

Neurologic Method

CNSCerebral cortexBasal gangliaBrainstem,CerebellumSpinal cord

PNSNerve rootsPlexusMotor nervesSensory nerves

• Meninges • Neuromuscular junction

• Muscle

Upper Motor Neuron Lower Motor Neuron

Neurologic Method

Focal ? Mulitifocal? Diffuse? Secondary to a Systemic illness?

History - provides clues in localizationNeurologic Examination - confirms and rules out

Neurologic Method Disturbances of Cerebrospinal Fluid and Its Circulation, including

Hydrocephalus, Pseudotumor cerebri, and Low-Pressure Syndromes Intracranial Neoplasms and Paraneoplastic Disorders Infections of the Nervous System and Sarcoid Viral Infections of the Nervous System and Prion Diseases Cerebrovascular Diseases Craniocerebral Trauma Multiple Sclerosis and Allied Demyelinative Diseases The Inherited Metabolic Diseases of the Nervous System Developmental Diseases of the Nervous System Degenerative Diseases of the Nervous System The Acquired Metabolic Diseases of the Nervous System Diseases of the Nervous System due to Nutritional Deficiency Alcohol and Alcoholism Disorders of the Nervous System due to Drugs and Other Chemical Agents

Major Categories of Neurologic Disease

Steps in the Diagnosis of Neurologic Disease

Elicitation of Clinical Facts

By history

By neurologic examination

Interpretation of symptoms and signs in terms of physiology and anatomy

Syndromic formulation and localization of lesion

ANATOMIC DIAGNOSIS

Anatomic diagnosis+Mode of onset and course+ Other medical data+Appropriate lab tests

Pathologic or etiologic diagnosis

Neurologic History

Often permits an accurate localization and determination of probable cause of the complaints, even before the neurologic examination is performed

Brings to focus the neurologic examination that follows

Each complaint should be pursued as far as possible- "What are the associated features?"

Neurologic History

Temporal course of the illness

Time of appearance

Rate of progression of the symptoms

Rapid, gradual, transient, stuttering, relapsing remitting

Patients' descriptions of the complaint

The same words often mean different things to different patients

Neurologic History

Corroboration of the history by others

Factors may impair patient's capacity to communicate

Episodes of loss of consciousness Family History

Many neurologic diseases have an underlying genetic component

Neurologic History

Medical illnesses

Neurologic diseases occur in the context of systemic disorders (DM, hypertension)

Drug use and abuse and toxin exposure

Prescribed and illicit Formulating an impression of the patient

Taking the History

Avoid leading questions, encourage to give accurate description of the symptom

Take notes, verify the history The setting, mode of onset and evolution and

course are important Decide if the patient is competent to give a

history

The Purpose of the Clinical Method of Neurology

Accurate Diagnosis Determine the proper treatment Helpful in prognosis Genetic counseling Initial step in the scientific study of clinical

phenomena and disease

Neurologic Examination

Needs practice Essential for ALL clinicians for screening for

neurologic dysfunction Performed in an orderly and systemic fashion to

avoid errors and serious omissions

Neurologic Examination

Describe what is found Compare the patients performance on tasks that

require simultaneous activation of both cerebral hemispheres

Reproduce the activity that elicits the symptoms Use of tests tailored to the patients problem can

be of value in assessing changes

Neurologic Examination

• Begins with observation of the patient

• Ends as the last part of the general physical examination

• Performed and recorded in sequential manner

• Thoroughness governed by clinical problem

• Modified according to the condition of the patient

Neurologic Examination

• Testing of Higher Cortical Functions

mini-mental examination

• Testing of Cranial Nerves

• Somatic Motor

• Somatic Sensory

Neurologic Examination

Mental Status Examination

Level of conciousness Awareness of self and environment Describe the responses to the minimum

stimulus necessary to elicit a reaction Orientation

Name, location and time Speech

Articulation, rate, rhythm, and prosody

Mental Status Examination

Language Content of patients verbal and written output Response to verbal commands Ability to read

Memory Immediate memory Short term memory Long term memory

Mental Status Examination

Fund of Information Inquire about major historic or current events

Insight and Judgement How patient would respond to situations with a

variety of outcomes

Abstract Thought Describe similarities between various objects List items of the same attributes

Mental Status Examination

Calculation Ability Have patient carry out a computation that is

appropriate to the patient's age and education Word problems involving simple arithmetic

Mental Status Examination• Intergrative sensory function

astereognosis

agraphesthesia

two-point discrimination

allesthesia

extinction

unilateral neglect and anosognosia

disorders of spatial thought

• Integrative motor function

apraxia

Mini Mental Status Examination

Orientation

TIME year, season, date, day, month

(1 point each)

PLACE state, country, town, hospital, floor

(1 point each)

Registration

Repeat names of 3 objects

(1 point per object)

Mini Mental Status Examination

Attention and Calculation

Serial 7’s or spell a 5 letter word backward

(1 point per subtraction or letter)

Recall

Recall names of three objects repeated previously

(1 point per object)

Mini Mental Status Examination

Language

Name a pencil, and watch (1 point each)

Repeat “no ifs, ands or buts”(1 point)

Follow a 3-stage command (1 point per step)

Read and obey the command (1 point)

Write a complete sentence (1 point)

Mini Mental Status Examination

Construction

copy two intersecting pentagons (1 point)

TOTAL = 30score of <24, more detailed investigation

Points

Orientation

Name: season/date/day/month/year 5 (1 for each name)

Name:hospital/floor/town/state/country 5 (1 for each name)

Registration

Identify three objects by name and ask the patient to repeat 3 (1 for each object)

Attention and calculation

Serial 7s; subtract from 100 5 (1 for each subtraction)

Recall

Recall the three objects presented earlier 3 (1 for each object)

Language

Name pencil and watch 2 (1 for each object)

Repeat "No ifs, ands or buts" 1

Follow a 3-step command (e.g., "Taek this paper, fold it inhalf, and place it on the table"

3 (1 for each command)

Write "close your eyes" and ask patient to obey writtent command

1

Ask the patient to write a sentence 1

Ask the patient to copy a design (e.g. intersecting pentagons) 1

Total 30

Cranial Nerves

CN I - smell

CN II - acuity, peripheral fields, inattention,

pupillary light reflexes and size of pupils,

opthalmoscopy

CN III, IV, VI - ocular movements, convergence, nystagmus

CN V - inspect masseter, temporalis tone/bulk,

corneal reflex, sensory V1, V2, V3

Cranial Nerves

CN VIII - otoscopy, threshold and acuity, Rinne, Weber, vestibular function

CN IX, X - phonation, nasality, swallowing, gag reflex

CN XI - SCM, trapezius

CN XII - lingual articulation, midline, lateral protusion, atrophy, fasciculations

Somatic Motor System

• Inspection

• Palpation

• Speed, strength of movement

• Muscle bulk, tone, coordination

Grade 0

Grade 1

Grade 2

Grade 3

Grade 4

Grade 5

Muscle Stretch Reflexes

Jaw jerk

Biceps (C5-6)

Triceps (C7-8)

Finger flexion (C7-T1)

Quadriceps (L2-4)

Ankle jerk (L5-S1-3)

Cutaneous abdominal

Plantar

22

22

22

22

22 22

22 22

11 11

+ ++ +

Cerebellar System

Finger to nose, rebound, alternating movements

Heel to knee

Nerve root stretching tests

Nuchal rigidity

Leg raising tests

Somatic Sensory SystemSuperficial sensory modalites

Light touch

Pain

Temperature

Deep sensory modalies

Vibration

Position Sense

Stereognosis

Romberg swaying test

  SignsCerebrum Abnormal mental status or cognitive impairment

SeizuresUnilateral weaknessa and sensory abnormalities including head and limbsVisual field abnormalitiesMovement abnormalities (e.g., diffuse incoordination, tremor, chorea)

Brainstem Isolated cranial nerve abnormalities (single or multiple)"Crossed" weaknessa and sensory abnormalities of head and limbs, e.g., weakness of right face and left arm and leg

Spinal cord Back pain or tendernessWeaknessa and sensory abnormalities sparing the head Mixed upper and lower motor neuron findingsSensory levelSphincter dysfunction

Table 361-2 Findings Helpful for Localization Within the Nervous System

  SignsSpinal roots Radiating limb pain

Weaknessb or sensory abnormalities following root distribution (see Figs. 25-2 and 25-3) Loss of reflexes

Peripheral nerve Mid or distal limb painWeaknessb or sensory abnormalities following nerve distribution (see Figs. 25-2 and 25-3) "Stocking or glove" distribution of sensory lossLoss of reflexes

Neuromuscular junction

Bilateral weakness including face (ptosis, diplopia, dysphagia) and proximal limbsIncreasing weakness with exertionSparing of sensation

Muscle Bilateral proximal or distal weaknessSparing of sensation

Table 361-2 Findings Helpful for Localization Within the Nervous System