- CN III oculomotor - CN IV trochlear

- CN V trigeminal - CN VI abducens - CN VII facial - CN VIII vestibulocochlear

- CN IX glossopharyngeal - CN X vagus - CN XI accessory nerve - CN XII hypoglossal

- superior rectus (looking up, down and out eye) - inferior rectus (looking down) - medial rectus (moves the eye towards nose) - inferior oblique (elevates the eyeball) - levator palpebrae superioris (elevate the eyelid)

- sphincter pupillae (constrict pupils) - ciliary muscles or ciliaris (for accommodation)

- due to paralysis of sphincter pupillae; loss of light reflex

- MIDRIASIS (dilation of pupil)

- thickest and largest sensory nerve

- CRANIAL NERVE V TRIGEMINAL NERVE

Module 3 Flashcards by Enn Cee

tubular stalk-like part of the brain made up of midbrain, pons and medulla oblongata from above down

BRAINSTEM

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MIDBRAIN

CN III oculomotor

- CN IV trochlear

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PONS

CN V trigeminal
CN VI abducens
CN VII facial
CN VIII vestibulocochlear

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MEDULLA

CN IX glossopharyngeal
CN X vagus
CN XI accessory nerve
CN XII hypoglossal

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carries information from olfactory bulb to the olfactory areas of the cerebral cortex
does not go through the thalamus
go through amygdala (center for memory and emotion)

CN I olfactory nerve

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special somatic afferent pathway concerned with reception and transmission of visual impulse and perception of vision or sight
rods (black and white)
cones (colored)
made up of ganglionic cells

CN II optic nerve

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carry nasal field

TEMPORAL FIBER

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carry the temporal field

NASAL FIBER

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loss of half field of vision

HEMIANOPIA

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same half of field of vision is lost in both eyes

HOMONYMOUS HEMIANOPIA

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lesion before the optic chiasm

MONOCULAR VISUAL PROBLEM

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lesion after the optic chasm

BINOCULAR VISUAL LOSS

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supplies majority of the extrinsic as well as the intrinsic muscles of the eyeball

CN III ocolumotor

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EXTRINSIC

superior rectus (looking up, down and out eye)
inferior rectus (looking down)
medial rectus (moves the eye towards nose)
inferior oblique (elevates the eyeball)
levator palpebrae superioris (elevate the eyelid)

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INTRINSIC

sphincter pupillae (constrict pupils)

- ciliary muscles or ciliaris (for accommodation)

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drooping of eyelid due to elevator palpebrae superiors

PTOSIS

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due to unopposed action of lateral rectus because of paralysis of medial rectus

LATERAL STRABISMUS

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due to paralysis of sphincter pupillae; loss of light reflex

MIDRIASIS (dilation of pupil)

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due to paralysis of extrinsic muscle

DIPLOPIA

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contralateral hemiplegia due to damage of crus cerebri

WEBER SYNDROME

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located in the tegmentum of the midbrain
supplies the superior oblique - depresses the eyeball (downward gaze)
only cranial nerve that emerges from the dorsal aspect of the brainstem

CN IV TROCHLEAR NERVE

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thickest and largest sensory nerve

CRANIAL NERVE V TRIGEMINAL NERVE

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corneal reflex

- sensation in the uppercase up to the forehead including the conjunctiva

V1: ophthalmic nerve

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sensation from maxillary teeth and gums

V2: maxillary nerve

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- sensory from mandibular teeth and gums

- V3: mandibular

- not the area of the trigeminal nerve

- angle of jaw

- for the angle of the jaw

- cervical spinal cord

- innervation of the muscles of mastication (masseter, temporalis, medial and lateral pterygoid)

- motor function of trigeminal nerve

- supplies the lateral rectus (move eye laterally away from the midline)

- CN VI ABDUCENS NERVE

- areas affected by the cavernous sinus

- CN III, IV, V, VI

- due to nonfiction of the lateral rectus leading to unopposed action of the medial rectus

- MEDIAL STRABISMUS

- mixed nerve with multiple motor and sensory component - supplies muscles developed from mesoderm of 2nd brachial arch a. muscles of the scalp, auricle and facial expressions with platysma b. stapedius muscle of the middle ear c. posterior belly of digastric and stylohyoid

CN VII FACIAL NERVE

- supplies secretomotor fibers to submandibular and sublingual salivary glands - carries taste sensation from anterior two thirds of tongue and form plate - carries proprioceptive sensation from muscles of facial expression

CN VII FACIAL NERVE

Clinical testing to judge the function of Facial Nerve

1. Frowning 2. Tight closure of eyelids 3. Smiling 4. Blowing of mouth

- characterized grossly by contralateral hemiplegia and ipsilateral total facial paralysis

MILLARD GUBLER SYNDROME

- compression of the nerve within the stylomastoid foramen

Bell's Paralysis

- lesion above the origin of nerve to stapedius | - loss of damping down effect in conduction of sound wave through stapes of the chain of the middle ear ossicles

HEMIHYPERACUSIS

- purely sensory nerve made up of two components vestibular and cochlear - VESTIBULAR - impulses required for maintenance of equilibrium or balance of the body - COCHLEAR - for the perception of hearing

CN VIII VESTIBULOCOCHLEAR NERVE

Vestibulocochlear nerve as well as facial nerve are relates to ___

Cerebellopontine Angle

- due to increase edolymphatic volume in membranous labyrinth - complains of recurrent attacks of vertigo and tinnitus

Meniere's Syndrome

- mixed cranial nerve - supply muscle developed from third branchial arch (stylopharyngeus muscle) - provides general sensation from posterior 1/3 of the tongue, tonsils, skin of the external ear, internal surface of tympanic membrane and the pharynx - stimulates the parotid gland

CN IX GLOSSOPHARYNGEAL NERVE

- characterized by severe, sharp, lancing pain in the region of the tonsil, radiating to the ear

GLOSSOPHARYNGEAL NEURALGIA

- latin word means "wandering" - sensation from posterior meninges, concha, skin at the back of the ear and in the acoustic meatus, part of external surface of the tympanic membrane, the pharynx, and larynx - supplies smooth muscles of whole tracheaobronchial tree, and foregut and midgut - testing the GAG REFLEX

CN X VAGUS NERVE

- head turning and shoulder elevation | - purely motor nerve to supply muscles developed from 6th branchial arch along with sternocleidomastoid and trapezius

CN XI ACCESSORY NERVE

Central lesion of accessory nerve may occur due to __

Lateral Medullary Syndrome and Jugular Foramen Syndrome

- purely motor nerve supplying muscles of tongue | - consists of all extrinsic and intrinsic muscle of tongue except palatoglossus

CN XII HYPOGLOSSAL NERVE

If Left hypoglossal nerve is paralyzed, tongue will deviate to the __ because the muscle is unopposed.

Left

The Clinical Method

1. The symptoms and signs are secured by history and physical examination 2. The symptoms and physical signs considered relevant to the problem at hand are interpreted in terms of physiology and anatomy 3. These analyses permit the physician to localize the disease process - This step is called anatomic, or topographic, diagnosis 4. From the anatomic diagnosis and other medical data 5. Physician should assess the degree of disability and determine whether it is temporary or permanent (functional diagnosis)

- Often one recognizes a characteristic clustering of symptoms and signs, constituting a syndrome of anatomic, physiologic, or temporal type. The formulation of symptoms and signs in syndromic terms is particularly helpful in ascertaining the locus and nature of the disease

anatomic, or topographic, diagnosis

- Special care must be taken to avoid suggesting to the patient the symptoms that one seeks - The setting in which the illness occurred, its mode of onset and evolution, and its course are of paramount importance.

History

2 main components: Psychiatric aspects - incorporate affect, mood, and normality of thought processes and content Neurologic aspects - include the level of consciousness, awareness (attention), language, memory, and visuospatial abilities.

Testing of Higher Cortical Functions

The function of the cranial nerves must generally be investigated more fully in patients who have neurologic symptoms than in those who do not.

Testing of Cranial Nerves

It should be kept in mind that observation of the speed and strength of movements and of muscle bulk, tone, and coordination are most informative and are considered in the context of the state of tendon reflexes.

Testing of Motor Function

Testing of the biceps, triceps, supinator-brachioradialis, patellar, Achilles, and cutaneous abdominal and plantar reflexes permits an adequate sampling of reflex activity of the spinal cord.

Testing of Reflexes

Attainable only through the subjective responses of the patient, it requires great patient cooperation.  It is not necessary to examine all areas of the skin surface. A quick survey of the face, neck, arms, trunk, and legs with a pin takes only a few seconds.

Testing of Sensory Function

An abnormality of stance or gait may be the most prominent or only neurologic abnormality, Having the patient walk tandem or on the sides of the soles may bring out a lack of balance or dystonic postures in the hands and trunk.

Testing of Gait and Stance

Parts of the Neurologic Examination

1. Mental Status Examination 2. Cranial Nerves 3. Motor System 4. Deep Tendon Reflexes 5. Cerebellar System 6. Sensory System 7. Meningeals 8. Autonomics

INITIAL INSPECTION

- Motor examination begins the moment the patient walks into your clinic - Have the patient undress - Determine the patient’s gestalt, somatotype or body build ``` - Inspect the size and contour of muscles Look for atrophy vs hypertrophy Body asymmetry Joint malalignment Fasciculations Tremors Involuntary movements ```

STATION AND GAIT TESTING

- Observe the Pt's station, the steadiness and verticality of the standing posture. - Test the gait by asking the Pt to walk freely across the room. - Look for unsteadiness, a broad-based gait, and lack of arm swinging. - Ask the Pt to walk on the toes, heels, and in tandem (from heel to toe along a straight line). - Request a deep knee bend. Ask a child to hop on each foot and to run.

(Strength Testing) | PRINCIPLES

- The Matching Principle - The Length-Strength Principle - The antigravity muscle principle

Select those movements that just about match your arm and hand strength. To gauge strength accurately, select movements that are neither too strong for you to possibly overcome nor too weak for you to judge their resistance.

The Matching Principle

muscles are strongest when tested from the shortest position

The Length-Strength Principle

muscles which support the standing posture against collapse by pull of gravity

The antigravity muscle principle

STRENGTH SCALE

0 - No contraction 1 - A flicker or trace of contraction 2 - Active movement with gravity eliminated 3 - Active movement against gravity 4 - Active movement against gravity and moderate resistance 5 - Normal power

Techniques in Testing for Muscle Weakness

- Be systematic: Rostrocaudal Sequence - Test the neck flexors and extensors - Test the shoulder girdle muscles

Command px to hold out the arms at the sides. Press down.

Arm elevation

With arms extended, patient resists your effort to elevate them

Arm adduction downward

With arms extended in front with wrists crossed, examiner tries to pull them apart

Arm adduction across the chest

With hands on the hips patient forces elbows back against your resistance

Scapular adduction

Have the patient try to do a push up or push against the wall

Scapular winging

The average Pt’s back is far too strong for the Ex to test by manual opposition. Two tests can be done: 1. With the Pt prone, ask the Pt to arch the back and rock on the stomach. Inspect and palpate the paraspinal muscles. 2. Have the Pt bend forward at the waist and straighten up. If you try to oppose the Pt’s straightening up from a bent waist, you may cause a back sprain or herniation of an intervertebral disc.

Testing for weakness of the large back muscles

1. Elbow flexors: The Pt tightly flexes the forearm. Brace one hand against the Pt’s shoulder. With the other hand, grasp the Pt’s wrist and attempt to straighten the Pt’s forearm. 2. Elbow extensors: If you give the matter no thought, you might try to test the triceps with the elbow locked in extension. But the triceps, an antigravity muscle, is tremendously strong, and with an average person against another average person, the locked-out elbow wins easily.

Testing for weakness of upper arm muscles: flexion and extension of the elbow

Testing for weakness of forearm muscles: wrist flexion and extension

1. Wrist flexors: The Pt makes a fist and holds the wrist flexed against your efforts to extend it. By hooking your fingers around the Pt’s fist and flexing your own wrist, you can pit your own wrist flexion against the Pt’s. Brace the Pt’s wrist with your other hand. 2. Wrist extensors: For support, rest the Pt’s forearm flat on his thigh or a tabletop. The Pt then holds the wrist forcefully cocked-up (dorsiflexed) as you try to press it down with the butt of your palm on the Pt’s knuckles.

Testing for weakness of finger muscles

Abduction-adduction of the fingers: Test by carefully figuring out how to match your strength against the Pt’s.

Testing for abdominal muscle weakness

Position:With the Pt supine (face up), ask for a sit-up or for the Pt to elevate the legs or the head. At the same time, watch the umbilicus as the abdominal muscles contract.

Testing for weakness of the hip girdle

1. Hip flexion:With the patient sitting, ask the Pt to lift a knee off of the table surface and to hold the thigh in a flexed position. With the butt of your palm, try to push the knee back down. 2. Thigh abduction and adduction: With the Pt sitting, have the Pt hold the legs abducted as you try to press them together with your hands on the lateral sides of the knees. Then have the Pt try to hold the legs adducted (squeezed together) as you place your hands on the medial sides of the knees to try to pull the knees apart.

Knee extensors: With the Pt prone, have the Pt try to touch the heel to the buttock to induce extreme flexion of the knee.Grasp the Pt’s ankle and oppose extension. Compare the extensor strength of the two legs. Knee flexors (hamstrings): The Pt holds the knee at an angle of 90 degrees, while you try to straighten it by grasping the Pt’s ankle.

Testing for weakness of the thigh muscles

1. Have the Pt dorsiflex, invert, and evert the feet. Inspect, palpate the leg, and check for the strength of these movements by manual opposition. 2. Plantar flexion of the foot is ordinarily too strong to test by manual opposition. Because the Pt walked on the balls of the feet during the gait examination, you already know that the plantar flexors can lift the entire body weight of the Pt. 3. The Pt holds the toes flexed or extended as the Ex attempts to press them back to the neutral position.

Testing for weakness of ankle and toe movements

Muscular resistance apart from gravity or joint disease the examiner feels when manipulating a patient’s resting joint is due to: Elasticity of the muscle Number and rate of motor discharges

Muscle tone

(Muscle Tone: Hypertonia) - Initial catch or resistance and then a yielding when the examiner manipulates the patient’s resting extremity - Clasp knife spasticity

SPASTICITY

(Muscle Tone: Hypertonia) - Increased muscular resistance felt throughout the entire range of movement when the examiner slowly manipulates a patient’s resting joint - Lead-pipe rigidity

RIGIDITY

(Muscle Tone: Hypertonia) Resistance equal in degree and range that the patient presents to the examiner as he tries to move a part in any direction

PARATONIA

(Muscle Tone: Hypotonia) - Decreased resistance - Increased range of motion of the joint movement i.e. hyperextensible knees or flaccid heel cords

FLACCIDITY

Technique for Eliciting Muscle Stretch Reflexes

1. Holding the percussion hammer and delivering the blow | 2. Eliciting the MSRs in the Neurologic Examination

With the patient’s jaw sagging loosely open, the examiner rests a finger across the tip and strikes it a crisp blow.

Jaw reflex

The examiner’s thumb places slight tension on the patient’s biceps tendon and the bicipital aponeurosis.The examiner strikes his thumbnail a crisp blow

Biceps reflex

(A) Dangle the patient’s forearm over your hand and strike the triceps tendon. (B) Cradle the patient’s forearm in your hand and strike the triceps tendon.

Triceps reflex

Cradle the patient’s forearm in one hand, placing the thumb on top of the radius. (A) The hammer strikes the examiner’s thumbnail rather than the patient’s radius. (B) Don’t whack away on the patient’s unprotected bone. The examiner may cradle both forearms side by side for accurate comparison of the responses of the two arms.

Brachioradialis reflex

The examiner supports the patient’s completely relaxed hand and briskly flips the patient’s distal phalanx upward, as though to flip a handful of water high into the air. The patient’s fingers and thumb flex in response to the stretch of the finger flexor muscles.

Finger flexion reflex (Tromner’s method)

The examiner depresses the distal phalanx and allows it to flip up.The extension of the phalanx stretches the flexor muscles, causing the fingers and thumb to flex. This method is effective only with very brisk muscle stretch reflexes.

Finger flexion reflex (Hoffman’s method)

The examiner strikes the patellar tendon a crisp blow. By placing a hand on the patient’s knee, the examiner feels and sees the magnitude of the response

Quadriceps femoris reflex, with the patient sitting

The examiner bends the patient’s legs to place slight tension on the patellar tendon.The blow then will deform the tendon and transmit a stretch to the muscle.

Quadriceps femoris reflex, with the patient supine

With the patient’s knee bent and relaxed, the examiner dorsiflexes the patient’s foot to place slight tension on the triceps surae muscle

Triceps surae reflex,with the patient supine.

a muscle stretch reflex. The maneuver is identical with the finger flexion method. Tapping the ball of the foot also elicits toe flexion.

Toe flexion reflex (Rossolimo’s sign)

After interruption of the UMNs to the lumbosacral cord, the great toe extends instead of flexing, a result called an __

extensor plantar response, extensor toe sign,or Babinski sign

MSR Grading

0 - Areflexia 1 - Hyporeflexia 2 and 3 - Normal 4 and 4+ - Hypereflexia

Stroking the skin of the abdominal quadrants or inner thighs elicits the superficial abdominal and cremasteric reflexes

Abdominal Reflex

Pricking the skin around the anus causes a quick, twitch-like constriction of the anal sphincter, the so-called __

anal wink

- Paralyzes movements in hemiplegic, quadriplegic distribution, not individual muscles - Atrophy of disuse - Hyperactive MSRs - (+) Clonus, Clasp-knife spasticity - (+) Extensor Toe Sign

Upper Motor Neuron Lesions

- Paralyzes individual muscles or sets of muscles in root or peripheral nerve distribution - Atrophy of denervation - (+) Fasciculations and Fibrillations - Hypoactive MSRs - Hypotonia

Lower Motor Neuron Lesions

Move an object along the lateral side of the foot

Chaddock

Squeeze hard on the Achilles tendon.

Achilles-toe reflex/Schaeffer

Press your knuckles on the patient’s shin and move them down.

Shin-toe reflex or Oppenheim

Squeeze the calf muscles momentarily.

Calf-toe reflex or Gordon

Make multiple light pinpricks on the dorsolateral surface of the foot

Pinprick toe reflex or Bing

Pull on the 4th toe outward and downward for a brief time and release suddenly

Toe-pull reflex or Gonda, Stransky

- Are sensorimotor functions that are lost after a neurologic lesion - i.e. loss of movement, loss of vision

Deficit Phenomenon

- Are sensorimotor functions that become increased or first emerge after a neurologic lesion - i.e. hyperactive MSRs, Babinski sign - The lesion has interrupted inhibitory connections

Release Phenomenon

rhythmic oscillations of a body part

Tremors

incessant, random, quick movement

Chorea

slow, writhing movement of fingers and extremities

Athetosis

prolonged slow, alternating contraction and relaxation of agonist and antagonist muscles

Dystonia

violent flinging movements of one half of the body

Hemiballismus

quick, lightning-fast movements of face and upper extremties

Tics

Three membranes that surround the brain

1. Dura Mater or Pachymeninx - Most external; Dense connective tissue 2. Arachnoid - Delicate layer of reticular fibers forming a weblike membrane 3. Pia Mater - Thin, translucent membrane - Adherent to the surface of the brain and spinal cord - Accurately follows every contour

Pia Mater + Arachnoid

Leptomeninges

Cranial Dura Periosteal layer: outer most layer; blood vessels and nerves Meningeal Layer: flat cells, gives rise to several septa

CRANIAL DURA MATER

(Septa) - Crista galli to internal occipital protuberance - b/n cerebral hemispheres

Falx Cerebri

(Septa) | between posterior fossa and cortex

Tentorium Cerebelli

(Septa) | small midsagittal septum below the tentorium which partially separates the cerebellar hemispheres

Falx Cerebelli

(Septa) | an extension of the dura mater that roofs over the pituitary fossa, perforated by the infundibulum

Diaphragma Sellae

opening b/n compartments

Tentorial Incisure (Notch)

- Branch of maxillary artery - Enters skull via foramen spinosum - Major blood supply of the dura

Middle meningeal artery

The ophthalmic artery gives rise to __

anterior meningeal branches

occipital and vertebral arteries provide __

posterior meningeal branches

Skull fractures lacerating branches of the meningeal artery produce epidural hemorrhages that separate the periosteal layer of the dura from the inner table of the skull

epidural hematoma

- From the foramen magnum to S2 - Caudal termination invests the filum terminal to form the coccygeal ligament - Spinal Cord: ends at L1 - Paired dural root sleeves: extensions of dura passing laterally around the spinal nerve rootlets

SPINAL DURA MATER

extends to the coccyx and becomes continuous with the periosteum

Coccygeal Ligament

- Delicate non vascular membrane - Between dura and pia mater - Passes over the sulci without following their contours

ARACHNOID

The space between the arachnoid and pia is filled with CSF

subarachnoid space

- Largest cistern | - b/n medulla and cerebellum

cerebellomedullary cistern (cisterna magna)

- surround posterior, superior and lateral surfaces of midbrain - contains the great vein of Galen and PCA and SCA

cisterna amaines or superior cistern

from conus medullaris to S2, contains the filum terminale and nerve roots of the cauda equina, where CSF is commonly withdrawn

Lumbar cistern

- Avascular, nutrients from CSF and underlying neural tissue - 2 components: Epipial Layer: meshwork of collagenous fiber bundles Intima Pia: fine reticular and elastic fibers - Epipial layer is absent over the convex surface of the cortex - Cerebral blood vessels lie on the intima pia anchored by arachnoid trabeculae

CORTICAL PIA MATER

- formed by intima pia | - where blood vessels enter and leave the CNS

Perivascular space

- Spinal cord blood vessels lie within the epipial layer - Denticulate ligaments: > epipial tissue that attach the spinal cord to the dural tube > Bases arise in the pia and apices are attached to the arachnoid and inner surface of the dura > Present throughout the length of the spinal cord - Intima pia is firmly attached to the spinal cord by the superficial glial membrane

SPINAL CORD PIA MATER

is a set of four structures, the ventricles, containing cerebrospinal fluid (CSF) in the brain. It is continuous with the central canal of the spinal cord

ventricular system

LOCATION OF CSF

Subarachnoid space and the ventricular system (ventricles, cistern, sulci of the brain, central canal)

CSF PRODUCTION

Choroid Plexus: within ventricles (lateral ventricles and roof of the third and fourth ventricles) of the brain Rate of production: 500 mL/day (0.3-0.4 mL/ min)

FUNCTION OF THE CSF

1. Mechanical protection by bouyancy - Low specific gravity of CSF (1.007) - Reduces the effective weight of the brain from 1.4 kg to 47g (Archimede’s principle) reduces brain inertia protects it against deformation 2. Removes waste products of metabolism, drugs and other substances that diffuse into the brain from blood. 3. Integrate brain and peripheral endocrine functions 4. Influence microenvironment of neurons and glial cells

CSF COMPOSITION

Protein - 60% of plasma Glucose - 1% of plasma RBC - 0 cells WBC - 0-3 cells

THE CSF PATHWAY

lateral ventricle >>> foramina of monroe >> 3rd ventricle >> cerebral aqueduct >> 4th ventricle >> central canal of the spinal cord or into the cisterns of the subarachnoid space via three small foramina (central foramen of Magendie and the two lateral foramina of Luschka)

- Separates blood from brain extracellular fluid - Formed by endothelial cells - Allow passage of water, some gases and lipid soluble molecules by passive diffusion and selective transport of glucose and amino acids - Prevent the entry of lipophilic neurotoxins

BLOOD-BRAIN BARRIER

- is a pair of barriers that separates peripheral and cerebral blood flow from the CSF - composed of epithelial cells of the choroid plexus at the peripheral blood–CSF boundary and the arachnoid membrane at the cerebral blood–CSF boundary - serves the same purpose as the BBB but facilitates the transport of different substances into the brain due to the distinct structural characteristics between the two barrier systems

blood–cerebrospinal fluid barrier

WBC: >50/mm3 PROTEIN: 100-250 GLUCOSE: 20-250 mg% OTHER FEATURES: inc. pressure; (+) organism on GS

BACTERIAL

WBC - 10-100/mm3 PROTEIN: 50-200 GLUCOSE: Normal or slightly decreased OTHER FEATURES: N or sl. increase ICP; special culture

VIRAL, FUNGAL, SIPROCHETAL

WBC: >25/mm3 PROTEIN: 100-1000 GLUCOSE:

TUBERCULOSIS

RBC: >500/mm3 PROTEIN: 60-150 GLUCOSE: Normal OTHER FEATURES: Xanthochromic; inc pressure

SAH

RBC: 50-200/mm3 PROTEIN: 50-150 GLUCOSE: Normal OTHER FEATURES: Inc Pressure

ICH, TRAUMA

Normal or few WBC PROTEIN: Normal GLUCOSE: Normal OTHER FEATURES: Normal unless with edema

ISCHEMIC STROKE

Normal or few WBC PROTEIN: Normal or slight increase GLUCOSE: Normal OTHER FEATURES: increase IgG fraction and oligoclonal bands

MULTIPLE SCLEROSIS

WBC 10-100/mm3 PROTEIN: usually increase GLUCOSE: Normal or slightly decreased OTHER FEATURES: Neoplastic cells in CSF

MENINGEAL CANCER

RAISED INTRACRANIAL PRESSURE

- Obstructed to CSF flow and/or absorption - Increase CSF production/CSF volume expansion - Generalized Cerebral Edema (Cytotoxic, Vasogenic or Interstitial) - Cerebral or Extracerebral mass - Increase in Venous pressure

- Obstruction of the basal cisterns - Extensive meningeal disease - At absorptive sites adjacent to cerebral convexities and SSS: ventricles are normal in size

OBSTRUCTED CSF ABSORPTION

- Establish symmetry and distribution of deficits for the following modalities: Light touch Pain and temperature Vibration and position sense

Sensory System

General Principles in Examination of Somatosensory System

1. Have the patient close their eyes to avoid visual clues and place full reliance on the skin stimuli 2. Compare homologous areas of the right and left sides and compare normal and suspected abnormal areas 3. The skin areas differ greatly in sensitivity to stimuli 4. Sensory lesions can have either positive phenomenon (too much sensation) or negative phenomenon (deficit/too little sensation)

The skin areas differ greatly in sensitivity to stimuli

- Skin over the face and armpits>> horny skin of palms and soles - Hairy skin>> glabrous skin - Forehead sensitive area for temperature discrimination

Terminology

Esthesia = touch or feeling Therm = heat Algesia = pain

- Loss of all modalities in the limbs (depending on the extent of the lesion) - Loss of pain and temperature of the face with or without "muzzle" area sparing and a lateral gaze palsy towards that side

Contralateral Pontine Lesion

- Loss of all modalities in the limbs (depending on the extent of the lesion) - Loss of pain and temperature of the face with or without "muzzle" area sparing and normal gaze - weakness of palate and tongue on side opposite to the limb sensory deficit

Contralateral Medullary Lesion

- Loss of pain, temperature and light tough below a specific dermatome level (may spare sacral sensation)

Contralateral Spinothalamic Tract

- Loss of all modalities at one or several dermatome levels - Loss of pain and temperature below a specific dermatome level - Loss of proprioception 'discriminatory' touch up to the similar level and limb weakness

Brown-Sequard Syndrome

- Bilateral loss of all modalities | - Bilateral leg weakness

Complete Cord Lesion

- Bilateral loss of pain and temperature | - Preservation of proprioception and discriminatory sensation

Central Cord Lesion

- discriminatory sensory deficit - sensory inattention (perceptual rivalry) - only minimal pain and temperature loss

Lesion of Contralateral Parietal Cortex

- selective deficit in face, arm, trunk or leg

Selective Cortical Lesion

- Loss of all sensory modalities including pain and temperature in the face, arm, trunk and leg

Contralateral Thalamic Lesion

- Initially, the area of total sensory loss is defined - Test object e.g. pin, should be moved from anaesthetic to normal area: it is more accurate to state when an object is felt rather when it disappears. - Examination of gait is important; with joint position impairment, sensory ataxia is evident. Romberg’s test is positive. Neuropathic burns/ ulcers or joins may be present

Testing for Pain and Temperature

For screening purposes test only the dorsum of the hands and feet (DeMyer) Test each area as required by the history (DeMyer)

Testing touch sensation

- Use the tuning fork versus finger or hot and cold tubes (DeMyer) - Remember you are testing temperature discrimination, not how much heat/cold the patient can tolerate! (DeMyer)

Testing temperature sensation

- Use of a pin, with both blunt and sharp ends (DeMyer). - Alternate blunt and sharp ends. - Make 3 successive pricks. - Ask the patient to respond “dull” or “sharp.” - Have the patient close his eyes. - Start with a normal area. - Avoid the thick skin of the palms and the soles.

Testing pain sensation

- Grasp the 4th digit by its side and wiggle it up and down - Show the patient which way is up and which way is down - Do not use different pressures or force or use a different tone of voice on the up or down movement - If position sense is normal distally it will be normal proximally

Testing for Position Sense

- Start with the patient’s eyes open. - Strike the tuning fork and apply to the patient’s finger- and/or toenails. - If the patient cannot feel the vibration at the nails for as long as you can, apply the fork to proximal bony prominences.

Testing for loss of vibration sense

Romberg Test

- Test for position of the body in space (proprioception) - Instruct the patient to stand,feet together, look straight the place yourself on the side to the patient then instruct the patient that if you feel dizzy, don’t worry i got your back

Result of Romberg Test

Normal: minimal swaying with eyes closed but not fall. Unilateral Vestibular Disease: sways to the side of the lesion, but the nervous system compensate. Many patients with the disease perform well on the Romberg Test. Dorsal Column Lesions (tabesdorsalis): sways much more with eyes closed and may fall unless supported. They do not compensate with time. Hysteria: causes the most difficulty in interpreting the swaying test. Patients are often gyrate wildly but usually do not fall, thus proving that they have intact balance.

- Just like the other test (AGAIN) close eyes, test left and right and compare it. - Use any object and place it on the palm and have the pt to identify what object it is. When testing the other palm use a different object

Stereognosis

- ability to discern the letter or number written to the skin. - Using a pointy object, write any letter or number to the skin of the patient and have the pt to identify what it is.

Graphesthesia

- ability to discern of identify body parts | - Ask the patient what is the name of a particular body part.

Autotopagnosia

There are 2 screening patterns:

1. side to side (usually compares the major dermatomes and peripheral nerve distributions) 2. distal to proximal (when peripheral neuropathy is a differential)

Module 3 Flashcards

(179 cards)