NERVOUS SYSTEM EXAMINATION

NERVOUS SYSTEM EXAMINATIONDr. Shahin Akter NipaMD (Phase A) Resident , Internal Medicine Chittagong Medical College & Hospital

Nervous System DefinitionThe nervous system is the part of body that coordinates its action and transnmits signals to and from different parts of the body.

NERVOUS SYSTEMCENTRAL NERVOUS SYSTEMBRAINSPINAL CORD

PERIPHERAL NERVOUS SYSTEMCRANIAL NERVES---12 pairs

SPINAL NERVES---31 pairs8 CERVICAL12 THORACIC5 LUMBAR5 SACRAL1 COCCYGEAL

AUTONOMIC NSSYMPATHETICPARASYMPATHETIC

SYMPTOMS(CANDIDATES FOR NS EXAMINATION)HEADACHETRANSIENT LOSS OF CONCIOUSNESS (TLOC)TIASTROKEDIZZINESSVERTIGOFUNCTIONAL SYMTOMS

EQUIPMENTS for EXAMINATION pin Cotton Tunning fork Reflex hummerkeyFlashlight Ophthalmoscope Vision screenersSnellen chartIshihara chartophthalmoscopeGloves Coffee

COMPONENTS

1.Higher Mental function 2.Cranial nerves examination 3.Examination of Motor system 4.Examination of Sensory system 5.Sign of Meningeal Irritation

A.HIGHER MENTAL FUNCTION

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1. Appearnce & Behavior

General elements- eg:attire,signs of self neglect Disturbed / Agitated/ Confused/ ApatheticNeat & Tidy/ Untidy Silent/ Monosyllabic/ Over TalkativeReaction to greetingPresence of Facial Tics/ Inappropiate Behavior

2.Emotional stateHappy/ Distressed/Depressed/IrritableEnjoy life/ Fed-up with life

3. DELUSION AND HALLUCINATION

Dellusion : It is a false belief in something which is not a fact.

Hallucination: It is a false perception of some special senses without any external object or stimulus.

4. ORIENTATION IN PLACE AND TIME

5.LEVEL OF CONSCIOUSNESS

Coma: Coma is state in which the patient makes no psychological meaninngful response to external stimulus or to inner need.Stupor: Show some response for instance to painful stimuliDementia: Patient awake and alert but muddled in time,place,and person and has impaired memory and mental processingDelirium: Patient confused but alertness is impaired

6. Memory:

1. Recent memory:Day of the weekDate in the month

2. Short term memory Memory for events of a few seconds or minutes past Test-repeat seven digits backwards Spell world backwards

3. Long Term Memory

7. INTELLIGENCE

General knowledge Abstraction Judgment Insight Reasoning

8. SPEECH AND LANGUAGEListen to the patients spontaneous speech, noting volume,rhythm and clarity.Ask the patient to repeat phrases such as yellow lorry to test lingual (tongue) sounds and baby hippopotamus for labial (lip) sounds, then a tongue twister, e.g. the Leith police dismisseth us.Ask the patient to count steadily to 30 to assess fatigue.Ask the patient to cough and to say Ah; observe the soft palate rising bilaterally.

SPEECH AND LANGUAGE (continued)

During spontaneous speech, listen to the fluency and appropriateness of the content, particularly for paraphasias and neologisms.Show the patient a common object, e.g. coin or pen, and ask its name.Give a simple three-stage command, e.g. pick up this piece of paper, fold it in half and place it under the book.Ask the patient to repeat a simple sentence, e.g. Today is Tuesday.Ask the patient to read a passage from a newspaper.Ask the patient to write a sentence; examine his handwriting.

SPEECH AND LANGUAGE (continued)

Dysarthriais a motor speech disorder. It results from impaired movement of the muscles used for speech production, including the lips, tongue, vocal folds etc.Aphasiais an impairment of language, affecting the production or comprehension of speech and the ability to read or write.Dysphasia is loss of or deficiency in the power to use or understand language as a result of injury to or disease of the brain.Dysphonia is commonly referred to as hoarse voice, refers to dysfunction in the ability to produce voice due to laryngeal disorder.

TYPES OF DYSPHAISIA:

1.EXPRESSIVE (MOTOR) DYSPHASIA: Damage to brocas area(inferior frontal region) Decrease verbal output Non fluent speech Errors of grammer and syntax Comprehension is intact

2. RECEPTIVE (SENSORY) DYSPHASIA:Dysfunction in Wernickes areaPoor comprehensionSpeech is fluentMeaninglessParaphasias(incorrect word)Neologisms(nonsense new words)

PARIETAL LOBE LESION:

Dyslexia:difficulty comprehending written language Dysgraphia:impairement of writing Apraxia: inability to carry out complex task despite having an intact sensory and motor system Agnosia:inability to interpret sensation NONDOMINANT PARIETAL LOBE DYSFUNCTION: Constructional apraxia: Inability to copy accurately drawing of 3 dimensional construction

Cranial Nerve ExaminationCN 1: OlfactoryCN 2: OpticVisual acuity Visual fieldsFundusCN 3: OculomotorPupil reactivity to light (direct and consensual) and accomadation Extraocular eye movements (superior, medial and inferior recti; inferior oblique)

Cranial Nerves (continued)CN 4: TrochlearExtraocular eye movements (superior oblique)CN 5: TrigeminalMuscles of masticationFacial sensation (V1, 2, 3 divisions)CN 6: AbducensExtraocular eye movements (lateral rectus)

Cranial Nerves (continued)CN 7: FacialFacial musclesTaste (anterior 2/3)CN 8: VestibulocochlearHearingVestibular functionCN 9: GlossopharyngealTaste (posterior 1/3) Uvula

Cranial Nerves (continued)CN 10: VagusPhonationPalate elevationCN 11: Spinal accessoryHead turnShoulder shrugCN 12: HypoglossalTongue protrusion

Cranial Nerve IThe Olfactory NerveEach nostril should first be evaluated for potency by compressing one nostril and having the patient breath through the opposite.

Each nostril should then be tested separately with a volatile, non-irritating substance such as cloves, coffee or vanilla. The patient should close his eyes, occlude one nostril and identify the substance placed under the open nostril.

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Causes of anosmia: -upper RTI -smoking,increasing age - ethmoid tumor -basal skull fracture,frontal fracture - congenital-Kallmanns syndrome -meningioma -following meningitis

Cranial nerve IIVisual AcuityPosition yourself in front of the patient.Each eye separately covering one at a time. Snellen's chart is used

Cranial nerve II (continued)

Cranial nerve II (continued)Colour Vision Test

Cranial nerve II (continued)OPTHALMOSCOPIC EXAMINATION

Retinal abnormalities. (A) Left optic atrophy. Note the lack of a pink neuroretinal rim. (B) Preretinal haemorrhage. (C) Pale white swollen disc. This is highly suggestive of giant cell arteritis, particularly if associated with visual loss. (D) Arteriolar occlusion of the horizontal nerve fibre layer.Multiple cotton-wool spots in human immunodeficiency virus (HIV) retinopathy. (E) Cytomegalovirus retinitis. Note the large superficial retinal infiltrate associated with flame haemorrhage. (F) Central retinal artery occlusion. Note the milky-white pale infarcted retina surrounding healthy pink fovea(cherry-red spot). (G) Central retinal vein occlusion. Note the widespread retinal haemorrhages and swollen optic disc. (H) Diabetic retinopathy with multiple dot and blot haemorrhages, indicating widespread capillary occlusion, a precursor of new vessel formation.

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Cranial nerves II , IIIPupils: Reaction to LightHave the patient look at a distant object Look at size, shape and symmetry of pupils.Shine a light into each eye and observe constriction of pupil. Flash a light on one pupil and watch it contract briskly. Flash the light again and watch the opposite pupil constriction (consensual reflex)Repeat this procedure on the opposite eye.

PUPIL Abnormalities: DM:small pupil,responds poorly,due to autonomic neuropathyArgyll Robertson pupil: -in syphilis -pinpoint,irregular pupil -constrict only on convergence

Holmes adie pupil: mid dilated,bilateral responds poorly to convergence Macus gunn pupil: optic nerve damage result in afferent pupillary defect both pupil contsrict to light

Cranial nerves III, IV and VIExtraocular Muscles

Cranial nerves III, IV and VI (continued..)Extraocular Muscles

3rd nerve palsy -unilateral ptosis(complete) -pupil:large(loss of parasympathetic ) -eye look inferolaterally cause:posterior communicating artery aneurysm

Horners syndrome: -partial ptosis -pupil:small(sympathetic loss) -drooping eyelid -decrease sweating

Myasthenia Gravis: bilateral ptosis

NYSTAGMUS:

1.Peripheral vestibular nystagmus: -horizontal -vertical -rotatory

2.CENTRAL VESTIBULAR NYSTAGMUS: unidirectional cause:-multiple sclerosis -CVD

3.VERTICAL NYSTAGMUS: brain stem lesion

Upbeat : upper brain stem lesion multiple sclerosis infarction Wernickes encephalopathy

Down beat: Arnold chiari malformation phenytoin /lithium intoxication

4.PERIODIC ALTERNATING NYSTAGMUS: Congenital Drug intoxication

5.ATAXIC NYSTAGMUS: Marked in abduction Demyelination of medial longitudinal bundle within brainstem

6.CONGENITAL NYSTAGMUS horizontal/pendular

7.ACQUIRED PENDULAR NYSTAGMUS cerebellar/brainstem disease multiple sclerosis spinocerebellar degeneration brainstem ischaemia

DIPLOPIA:

Pure horizontal: 6th CN palsy

Vertical diplopia: 4th CN palsy, Thyroid eye disease

Cranial Nerve V

Cranial Nerve V (continued)Sensory Examination

Cranial Nerve V (continued)

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Cranial Nerve V (continued)

Cranial Nerve V (continued)Jaw JerkThemandible or lower jawis tapped at a downward angle just below the lips at the chin while the mouth is held slightly open. In response, themasseter muscles will jerk the mandible upwards. Normally this reflex is absent or very slight. However in individuals withupper motor neuron lesions the jaw jerk reflex can be quite pronounced.

TRIGEMINAL NERVE EXAMINATION

Unilateral loss of 5th nerve: direct injury facial fracture local invasion by cancer

Lesion in cavernous sinus: loss of corneal reflex V1 ,V2 sensory loss 3,4 ,6 CN also affected

Trigeminal neuralgia - due to neurovascular compression -sevre lancinating pain in V2,V3Reactivation of VZV affect any sensory nerveBrisk jaw jerk: pseudobulbur palsy

Cranial Nerve VIIFacial Nerve

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Cranial Nerve VIIFacial Nerve (continued)

Cranial Nerve VIIFacial Nerve (continued)Sensory Function

Cause of LMN facial palsy cerebellopontine angle tumorAcoustic angle tumorTraumaParotid tumour

Bilateral facial palsy:GBSSarcoidosis Lyme disease HIV

Cranial Nerve VIIIVestibulocochlear Nerve

Cranial Nerve IX and XGlossopharyngeal & Vagus Nerve

Unilateral X nerve palsy(recurrent laryngeal) lung cancer post thyroid surgery mediastinal lymphoma aortic arch aneurysm

Bilateral X nerve lesion: Progressive bulbar palsy(MND)Bilateral supranuclear lesion(Pseudobulbur palsy)CVDMultiple sclerosis

Unilateral IX and X lesion:Skull base tumorSkull base fractureStroke(lateral medullary syndrome)

Cranial Nerve XIAccessory Nerve

Have patient shrug shoulder against resistance and evaluate strength of Trapezius muscle.Have patient turn head to one side against resistance and evaluate strength and observe contracting sternomastoid muscle

Cranial Nerve XIIHypoglossal NerveAsk the patient to move the tongue side to side in the mouth and feel the strengthAsk the patient to open mouth and observe the tongue whether any atrophy or fasciculation present or not. Ask the patient to protrude the tongue. Protruded tongue deviates to the side of lesion of 12th nerve.