NEUROLOGIC INVESTIGATIONS

CSF AnalysisCSF (general info):

Produced by choroids plexus of ventricles, absorbed through villi of arachnoid granulations that project into the dural venous sinuses

Production rate=.5 mL/min, total volume=150 mL, entire volume replaced every 5 hrsLumbar puncture:

CI: space occupying lesion causing mass effect, increased ICP (LP can cause cerebral or cerebellar herniation) CT: should be performed prior to LP (except in cases of suspected meningitis) Complication: low pressure HA is most common (tx: pt should lie flat, increase liquid intake and caffeine) Technique:

o Pt position: lateral recumbent, legs flexed up over abdomen, pillow b/w legso Level: L3-4 vertebral interspace (@ level of anterior superior iliac spine); spinal cord ends at L1-2o Needle: inserted w/ bevel facing up, directed slightly rostrally to coincide w/ downward angulation of

spinous processInterpretation of CSF findings:

Normal CSF: clear, colorless fluid w/ glc content 2/3 that of blood, trace ptn, <5 cells present (lymphocytes), opening pressure of 60-150 mm water

RBCs No xanthocromia Traumatic tapXanthocromia (yellow discoloration of supernatant of spun CSF sample)

SAH, hemorrhagic encephalitis

WBCs Polymorphs Bacterial or early viral infectionLymphocytes Infection (viral, fungal, mycobacterial), demyelination (MS),

CNS lymphomaElevated ptn Infection, demyelination, tumor, ageLow glc Bacterial or mycobacterial infectionOligoclonal bands Demyelination (MS), CNS infections (Lyme Disease),

Noninfectious inflammatory processes (SLE)Positive EBV PCR Highly suggestive of CNS lymphoma in pts w/ AIDS or other

immunosuppressed states

CT Concept

Characterizes degree of x-ray attenuation by tissue. Attenuation is the removal (by absorption or scatter) of x-ray photons and is quantified on an arbitrary scale (Hounsfield units) that is represented in shades of gray. Attenuation is dependent on atomic number and physical density of tissue.

Axial or coronal plane Iodine is contrast agent used (if pt has allergy, do MRI instead); contrast enhancement indicates local disruption of

blood-brain barrierUtility

Initial investigation used in variety of neuro d/o (HA, trauma, seizures, SAH, stroke) Investigation of choice for demonstrating fresh blood

Safety, tolerability, complications CI: pregnancy

MRIConcept

Uses radio frequency pulses (not x-rays). Images result from varying intensity of radio wave signals emanating from tissue in which hydrogen ions have been excited by a radio frequency pulse

Pt is placed in a magnet and then a radio frequency (RF) is administeredo TE=time to echo, the time interval at which the signal intensity is measuredo TR=time to repetition, the time between RF pulses

Gadolinium is contrast agent usedTypes

T1-weightedo Short TE/TRo Fat is bright, water (CSF) is darko Used to obtain gadolinium-enhanced images

T2-weightedo Longer TE/TRo Water (CSF) is bright

FLAIR (fluid attenuated inversion recovery)o Strong T2-weighted image, but one in which the signal from CSF has been inverted and is thus of low rather

than high intensityo Used for demonstrating early or subtle T2 signal changes such as accumulation of edema

Susceptibility-weighted imagingo Sensitive to the distruptive effect of a substance on the local magnetic field (calcium, bone, blood b/d

products ferritin and hemosiderin); areas of increased susceptibility appear black Diffusion-weighted imaging (DWI)

o Demonstrates cellular toxicity w/ high sensitivityo Most commonly used in diagnosis of acute strokeo Areas or restricted diffusion appear bright on DWI

Utility Provides better anatomic definition Imaging of posterior fossa and craniocervical junction DWI is most sensitive for demonstrating early tissue ischemia and is useful in evaluation of pts w/ suspected stroke

Safety, tolerability, complications Modality of choice in pregnancy When contrasted imaging is required, MRI may be preferable to CT when there is a history of allergy to IV contrast

(gadolinium and iodine are not cross-reactive), or liver disease (gadolinium is not nephrotoxic) CI: metal objects, pacemaker/defibrillator devices, claustrophobia

EEGFrequency patterns

Alpha (8-13 Hz): posterior head regions in relaxed awake state w/ eyes closed Beta (14-30 Hz): frontal regions in relaxed awake state w/ eyes closed Theta (4-7 Hz): drowsiness/sleep Delta (.5-3 Hz): drowsiness/sleep

Technique Montage=pattern w/ which electrodes are connected to each other

o Bipolar: all electrodes are active, records difference in electrical activity b/w 2 adjacent electrodeso Referential: electrical activity recorded beneath the active electrode relative to a distant or common average

electrodeClinical utility

Limitationso Abnormal EEGs rarely are etiology-specifico EEG records electrical activity of cortical neurons, and thus surface EEG may be insensitive to dysfunction

of deep structureso Interictal EEG may only be abnormal in 30% of adults w/ epilepsy

Abnormal patternso Focal arrhythmic or polymorphic slow activity in theta/delta range local pathology in underlying braino Generalized arrhythmic slow activity diffuse encephalopathyo Sharp and spike wave discharges w/ or w/o accompanying slow wave interictal epileptiform findingso Rhythmic spike or sharp and slow wave discharges or rhythmic slow waves focal or generalized

electrographic seizures

Nerve Conduction Studies (NCS) Electrical stimulus applied over a nerve, and recordings are made from surface skin electrodes

o Motor study: recording electrodes placed over end plate of a muscle innervated by nerve being stimulated; nerve stimulated in at least 2 locations (distal, proximal) and distance b/w 2 sites is measured

Distal latency=time interval b/w stimulation over distal portion of nerve and initiation of CMAP CMAP=compound muscle action potential Conduction velocity=calculated by measuring the difference in latency to CMAP initiation b/w

proximal and distal sites of stimualtiono Sensory study: nerve stimulated at one site; SNAP (sensory nerve AP) recorded either at more proximal site

(orthograde study) or more distal site (antergrade study) Utility: assists localization of pathology w/in PNS

Nerve Conduction Studies in Demyelinating and Axonal NeuropathiesDemyelinating Axonal

Distal latency Prolonged NormalConduction velocity Markedly reduced Normal; maybe slightly reducedCMAP amplitude Normal or mildly reduced Reduced

EMG Needle is inserted into individual muscles; recordings are made of muscle electrical activity upon insertion (insertional

activity), while muscle is at rest (spontaneous activity) and during contraction (volitional motor unit potentials) Utility: assists localization of pathology w/in PNS

EMG in Neurogenic and Myopathic DisordersNeurogenic Myopathic

Insertional activity Increased (active denervation) Usually normal Increased (necrotizing myopathies)

Spontaneous activity Increased (active denervation) Usually normalIncreased (necrotizing myopathies)

Volitional motor unit potentials Large amplitude, polyphasic Small amplitude, polyphasicRecruitment Reduced Usually normal

THE APPROACH TO COMA AND ALTERED CONSCIOUSNESS

General Coma=state of unarousable unresponsiveness Describe alterations of consciousness in terms of a pt’s responses to various degrees of stimulation Glasgow Coma Scale—has prognostic value in head trauma pts, is reproducible, and easy to use

Clinical Approach to Altered Consciousness1. ABCs: airway, breathing, circulation2. Look for obvious clues to etiology

a. Medical problems (diabetes, hepatic failure, seizure disorder)b. Circumstances in which patient was foundc. Check for meningeal signs

3. Try reversing common reversible etiologiesa. Naloxone (opiate OD)b. Thiamine (EtOH)—give before dextrose, which can precipitate Wernicke’s encephalopathyc. Dextrose

4. Check brainstem reflexes and look for focal signsa. Focal signs present suspect structural cause neuroimagingb. Focal signs absent suspect diffuse cause metabolic, toxic and/or infectious workup, neuroimaging

Examination1. Mental status testing

a. Assess level of consciousness—an increasing gradient of stimulation should be applied and patient’s responses recorded

b. For many pt’s, further cognitive testing may be impossible2. Cranial nerve testing to assess brainstem function. Test these bs reflexes:

a. Pupillary—II (afferent) III (efferent)b. Oculocephalic (doll’s eyes)—VIII (afferent) III, IV, VI (efferent)—forcibly turn head horizontally and

vertically and observe for conjugate eye movement in opposite direction (CI if cervical spine injury not r/o)c. Caloric testing (if necessary, i.e., if turning head is CI or does not result in eye movement; never assume eyes

are immobile unless caloric testing has been done)—inject 50 mL ice water into each ear and observe for conjugate eye deviation toward the ear injected

d. Corneal—V (afferent) VII (efferent)e. Gag—IX (afferent) X/XI (efferent)

3. Motor tonea. Motor toneb. Decorticate posturing—bs dysfunction slightly more superior that that of decerebrate posturingc. Decerebrate posturing—bs dysfunction

4. Muscle stretch reflexes, Babinski sign5. Sensory testing usually limited to testing of light touch or pain sensation; applying nailbed pressure to each limb

may be useful in looking for gross sensory abnormalities

Differential DiagnosisGeneral:

2 ways in theory in which consciousness can be depressed: dysfunctional bs (e.g. pontine hemorrhage) or bilateral cerebral hemisphere dysfunction (e.g. hypoglycemia); BUT, unilateral cerebral hemisphere lesions, if large or severe enough to cause swelling and compression of opposite hemisphere or downward pressure on bs, can also lead to coma

General approacho +/- bs reflexes indicates how deep coma iso +/- focal signs narrows differential and guides workup

Structural causes of depressed consciousness: acute ischemic stroke, acute intracranial hemorrhage, brain tumor (w/ edema or hemorrhage), brain abscess

Diffuse causes of depressed consciousness: metabolic, toxic, infectious, hypoxic-ischemic (respiratory failure, cardiac arrest)

Laboratory and Radiographic Studies If STRUCTURAL cause is suspectedurgent head imaging, usually w/ noncontrast head CT; use CT rather than

MRI even if focal brainstem signs are found (d/t possibility of a large cerebral hemisphere lesion compressing the bs) If DIFFUSE cause suspected extensive metabolic, toxic, or infectious workup

o Blood testing: CBC, electrolytes, glc, liver function testso If infection suspected: chest x-ray, urinalysis, blood or urine culture, LP (BUT perform CT 1st! to avoid

precipitating brain herniation)o Head imaging usually needed b/c it may demonstrate signs of global hypoxic-ischemic injury, diffuse

cerebral edema, or bilateral lesions mimicking a diffuse process EEG nonspecific, but can be of use in helping to assess how deep a coma is, based on degree of background

slowing

Treatment and PrognosisTreatment

Diffuse metabolic, infectious, toxic medical management Structural neurosurgical intervention If ICP increased raise head of bed, hyperventilation, osmotic diuretics (mannitol), corticosteroids for edema a/w

brain tumorsPrognosis

Depends ono Etiologyo Age

Special Topics1. Persistent vegetative state—may follow prolonged coma and is characterized by preserved sleep-wake cycles and

maintenance of autonomic functions w/ absence of awareness and cognition2. Locked-in syndrome—awareness and cognitive function are preserved but almost complete paralysis occurs; cause by

large lesions in base of pons3. Brain death—irreversible cessation of all functions of the entire brain, including the brainstem

a. Comatoseb. Absent bs reflexesc. No spontaneous respirations even when PCO2 has been allowed to rise (apnea test)

NEURO-OPHTHALMOLOGY

Anatomy Coherent visual image: retinal axons lateral geniculate nucleus optic radiations in cerebral cortex primary

visual cortex (visual area 1, Brodmann’s area 17, striate cortex). V1 receives visual info from contralateral visual hemifield.

Perception of motion, depth, color, location, form: V1 o Associative visual cortex (areas 18, 29)o Higher-order centers in posterior parietal and inferior temporal cortices

Visual Loss+/- visual phenomena

1. Positive: brightness, shimmering, sparkling, hallucinations, shining, flickering, colors (suggest migraines or seizures)2. Negative: blackness, grayness, dim vision, shade-obscuring vision (suggests stroke, TIA)

Clinical evaluation of visual loss1. Visual acuity problem in refractive apparatus of eye or optic nerve

a. Hand-held Snellenb. Pinhole (if VA is poor) if pinhole test improves VA, then problem is in refractionc. If pt cannot read the letters count fingers perception of movement perception of bright light

2. Assessment of color visiona. Ishihara plates (red desaturation seen early in optic nerve problems [esp. optic neuritis])

3. Test for afferent pupillary defectsa. Size of pupil (anisocoria?)b. Light reaction, direct and consensualc. Accomodation (near reaction)

4. Visual fields5. Ophthalmoscopic exam retinal nerve fiber layer damage, optic atrophy, swollen disc, abnormal disc, vascular

lesions, retinal emboliMonocular visual loss v. binocular visual loss

Monocular suggests problems in eye, optic nerve, or chiasm Binocular suggest chiasm or retrochiasmal lesion

Visual Loss According to LocalizationLesion Level Visual Field DefectOptic nerve Ipsilateral blindnessChiasm Bitemporal visual field defect (tunnel vision)Optic tract Contralateral homonymous hemianopiaOptic radiations (parietal) Contralateral inferior homonymous quadrantonopiaOptic radiations (temporal, or Meyer’s loop) Contralateral superior homonymous quadrantonopiaOptic radiations (both) Contralateral homonymous hemianopiaOccipital cortex Contralateral homonymous hemianopia w/ macular sparing

Disorders of the PupilAnatomy

Light retinal ganglion cells optic nerve optic chiasm optic tract pretectal midbrain nuclei (Edinger-Westphal) in rostral portion of 3rd nerve

Efferent PNS fibers from EW travel w/ CNIII (thru cavernous sinus), ultimately synapsing in ciliar ganglion sphincter pupillae (constrictor)

SNS innervates dilator pupillaeo 1st order neuron: ipsilateral posterolateral hypothalamus down brainstem to IML @ C8-T1 spinal levelo 2nd order neuron: synapse in superior cervical gangliono 3rd order neuron: travel along internal carotid into cavernous sinus orbit

Clinical Assessment

Condition Signs/Symptoms Etiology TestPhysiologic anisocoria

Asymmetric pupils Up to 25% of normal people Amount of anisocoria does not change with different illumination

Horner’s syndrome

Ipsilateral miosis, ptosis, ipsilateral anhidrosis

Impaired SNS innervation of pupil Cocaine eyedrops that fail to dilate the abnormal pupil (neg)Hydroxyamphetamine eyedrops allows for pharmacologic localization if cocaine test is neg pre- v. post-ganglionic Horner’s (the pupil w/ post-gang Horner’s fails to dilate)

CNIII palsy (complete)

Mydriasis, ptosis, ophthalmoplegia

Compression of CNIII: initially produces dilated pupil w/o compromising eye movements (b/c PNS fibers run in outer part of CNIII, while motor fibers are more internal)Vascular compromise CNIII

ischemia (diabetes): normal, reactive pupil, but palsy of ocular muscles innervated by CNIII

Adie’s pupil (tonic pupil)

Dilated, with segmental contraction and light-near dissociation; anisocoria, photophobia, blurred near vision

Interruption of PNS supply arising from ciliary ganglion

LND: normally pupil constriction to light greater than to near stimulus; opposite is true in LND (present when there is a defect in light response as in optic neuropathy or d/t aberrant regeneration as in tonic pupil)

Argyll Robertson pupils

Small, poorly reactive to light but have preserved near response (accommodation normal)

Syphilis

Abnormal Optic DiscSee pages 38-39 (table)Note: painful vision loss=optic neuritis; sudden painless vision loss=ischemia

Diplopia

Some Terms Used to Describe Eye MisalignmentStrabismus Misalignment of eyesComitant strabismus Misalignment is constant in all directions of gaze, and each eye has full ROM

(ophthalmologic problem)Noncomitant strabismus Degree of misalignment varies w/ direction of gaze (neurologic problem)Phoria Misalignment of eyes when binocular vision is absentTropia Misalignment of eyes when both eyes are opened and binocular vision is possible

Anatomy of Eye Movements (SO4 LR6 AR3) CNIII: dysfunction produces droopy dilated down and out; most common cause of CNIII dysfunction in older adults

include microvascular occlusion and ischemia d/t HTN, diabetes mellitus and atherosclerosis; patterns of dysfunction include

o CNIII nucleus: bilateral ptosis, weakness of contralateral superior rectuso Subarachnoid space: meningismus, constitutional sxs, CN defectso Tentorial edge compression: depressed level of consciousness, hemiparesis, hx of trauma or supratentorial

mass lesion CNIV: superior oblique intorts, depresses, adducts; dysfunction is worse on downgaze and pts c/o diplopia while

reading and descending stairs and compensate w/ a contralateral head tilt (diplopia improves w/ head tilt away from side of lesion

CNVI: lateral rectus; o Lesions produce esotropiao Destruction of abducens nucleus in brainstem ipsilateral conjugate gaze palsy b/c of damage of

interneurons connected to contralateral 3rd nerve through the MLF (medial longitudinal fasciculus)Clinical Evaluation of Diplopia

Ask:o Monocular or binocular?o If binocular, is it horizontal or vertical?o Is it worse near or far?o Is the problem localized to an extraocular muscle (paresis or fatigue), brainstem MLF (internuclear

opthalmoplegia), or to the orbit itself? Tests

o Cover test: detects a tropia; pt fixates on a small target, then cover one eye; watch other eye; if eye makes a refixation movement, this means that this eye was not aligned on the target; if eye moves nasally, pt has an exotropia, and if temporally, and esotropia; e.g. CNIII palsy exotropia and hypotropia of paretic eye; CNVI palsy produces esotropia of affected eye

o Alternate cover test: detects phoria (eso or exophoria); phoria do not cause diplopia b/c eyes are aligned when both are opened simultaneously

o Park’s 3-step test: detects CNIV palsy; 1) hypertropia of paretic eye 2) which increases when the pt looks to the opposite side and when 3) pt tilts the head to the same sider

o Oculocephalic maneuver (doll’s eye test)o Saccades: rapid conjugate movement of the eyes between objects (fingertips); in general d/o of eye

movements will produce slowness of saccades in the direction of the paretic muscleo Pupillary size and reflexeso Periocular signs or proptosis

Horizontal Gaze Internuclear opthlamoplegia (INO)

o MLF connects CNVI nucleus w/ contralateral CNIII nucleuso Clinical characteristics of a RINO

Inability to adduct R eye in left lateral gaze Nystagmus of abducting left eye Adduction during convergence is maintained b/c this action does not depend on the MLF

o Bilateral INOs can be seen in Wernicke’s encephalopathy “One and a half syndrome”

o D/t lesion of ipsilateral MLF + ipsilateral PPRF (paramedian pontine reticular formation=premotor substrate for ipislateral horizontal gaze) OR CNVI nucleus; causes are MS and brainstem ischemia

o Clinical characteristics Ipsilateral lateral gaze palsy and INO in contralateral lateral gaze The only movement present in the lateral plane is abduction of contralateral eye

Vertical Gaze Controlled by rostral interstitial nucleus of the MLF (riMLF) located in the pretectal area near CNIII nucleus. Fibers

controlling upgaze from riMLF cross to contralateral side using posterior commisure to communicate w/ inferior oblique and superior rectus subnuclei of CNIII complex

Abnormal vertical gaze movements d/t dorsal midbrain syndromeso Parinaud’s syndrome: upgaze disturbance, convergence-retraction nystagmus on attempted upgaze, light-

near dissociation of pupils (d/t pineal tumor compressing dorsal midbrain)o Skew deviation: vertical tropia d/t brainstem or cerebellar lesion; hypotropic (lower) eye often on side of

lesion

Supranuclear Eye Movements

Saccades: rapid eye movements that redirect the fovea to a new target Voluntary horizontal saccades originate in frontal eye field and superior colliculus contralateral to the direction of

gaze; these areas have direct connection to contralateral PPRF Vertical saccades may also originate in frontal eye fields or superior colliculus but connect to contralateral riMLF Ocular motor apraxia=inability to produce saccades Abnormal saccades: hypermetric (overshoot), hypometric (undershoot); see table 4-6 on p. 42

Pursuit Movements: permit eyes to conjugately track a moving visual target to keep it in focus Control is hemispheric and ipsilateral

Vestibulo-ocular Reflex (VOR): coordinates eye movements w/ head movement, allowing visual image to not slip during head movement

Semicircular canals (rotation) and otoliths (linear acceleration)vestibular nucleiabducens nuclei CN III/IV via MLF

Abnormalities of VOR result in nystagmus:Nystagmus: rhythmic to-and-fro movement of the eyes

Typeso Rhythmico Jerk: eye drifts away from fixation in a pursuit-like movement and returns with a fast, saccadic movement;

the direction of nystagmus is named by the direction of the saccadic fast component Etiologies

o Congenitalo Physiologico CNS dysfunction, peripheral vestibular loss, visual loss

Peripheral: usually unidirectional, w/ fast phase away from the side of the lesion; combines horizontal and torsional movements and is inhibited by fixation; tinnitus or deafness often present; severe vertigo; duration is short by recurrent

Central: normally bi-directional, often purely horizontal, vertical, or torsional, and not inhibited by fixation; tinnitus and deafness rarely present; mild vertigo; duration may be chronic

See table on p. 43 (4-7)

THE APPROACH TO WEAKNESS

Approach to Weakness Flowchart1. Make sure that true weakness (i.e. decreased strength) is the complaint (NOT general sense of fatigue, NOT clumsy or

numb, NOT a limb that is too painful to move)2. ID which muscles are weak3. Determine the pattern of weakness (muscle, NMJ, nerve, root, plexus, cord, brain?)4. Look for associated signs/symptoms (numbness, tingling, painful; reflexes?). Are they consistent with localization?5. Consider the differential diagnosis of d/o w/in your localization6. Use lab tests and EMG/NCS if needed

a. Blood tests or neuroimagingb. EMG/NCS to further localize problem to a particular segment of the peripheral nervous system

Differential Diagnosis of Weakness

Anatomic Location

Pattern of Weakness Associated Si/Sx Lab Studies Differential Diagnosis

Primary Muscle Symmetric, proximal weakness and can affect neck muscles (not usually affected in a brain or nerve lesion)Distal muscles affected later or not as severely

Muscle pain (if process is inflammatory, e.g. polymyositis)Sensory si/sx are not present

Serum CK level is elevated in some d/oEMG may show characteristic “myopathic” pattern

Acquired (myopathies) d/t inflammatory or toxic etiologyCongenital (muscular dystrophies)

NMJ Proximal weakness; some can lead to ptosis and weakness of extraocular, bulbar, and neck musclesFluctuation of weakness is important—degree may change from hr to hr, may be worse after using muscles or toward end of day and improve after resting or in the morning (fatiguability) or improve after exercise

Sensory si/sx are not presentANS features sometimes present

EMG/NCS can demonstrate nearly pathognomonic findings for some d/oSome d/o have specific serum markers (anti-AChR Igs in myasthenia gravis)

Myasthenia GravisLambert-Eaton Myasthenic Syndrome

Peripheral NerveMononeuropathies Weakness of muscles

innervated by a single peripheral nerve

Sensory sxs (e.g. numbness, tingling, pain) in distribution of the peripheral nerve

EMG/NCS: confirm clinical suspicion of problem w/ peripheral nerveNCS: does the pathologic process involve axons or myelin of the nerveEMG: relative acuity or chronicity of d/o

Usually occur d/t entrapment (e.g. Carpal Tunnel Syndrome)

Mononeuropathy Multiplex

Certain systemic d/o can lead to dysfxn of multiple peripheral nerves in succession

Characteristically a/w pain

A/w systemic vasculitis, metabolic, or rheumatologic d/o

Polyneuropathy Peripheral nerves are all affected diffusely, w/ dysfxn occurring in longest nerves 1st (progression of weakness from distal to proximal, symmetric)

Usually have associated sensory loss and depressed or absent reflexes, especially in distal extremities

Demyelinating polyneuropathies can be hereditary (Charcot-Marie-Tooth) or acquired (Guillain-Barre)

Nerve RootRadiculopathy Dysfxn of single nerve root Pain or tingling

radiating out from back or neckObjective sensory loss rare in d/o of single nerve root b/c of overlap from adjacent roots

EMG/NCS can confirm that nerve roots are the culprit; can differentiate b/w root v. peripheral nerve problemMRI (spine): for single rad., to r/o

Herniated discsShingles

Polyradiculopathy Dysfxn of multiple nerve roots

InflammationInfection

If nerve root subserves a particular muscle stretch reflex, that reflex may be depressed or absent

structural etiologiesLP: for polyrad. to look for infectious or inflammatory processes

PlexusBrachial Multiple muscles in a limb

are weak and do not conform to a particular nerve root or peripheral nerve pattern

Sensory findings (in distribution of one or more roots or nerves)Dropped reflexes

EMG/NCS: confirms the localizationMRI of brachial or lumbosacral plexi to r/o mass lesions

Idiopathic inflammation, radiation, metastases, hemorrhage, traumaDiabetic pts characteristic lumbosacral plexopathy (diabetic amyotrophy)

Lumbosacral

Spinal Cord Weakness in UMN pattern below lesion, and in a nerve root pattern at lesion level

Maybe sensory loss below level of lesion d/t interruption of ascending tractsReflexes below lesion are typically increased, and Babinski may be +Bladder/bowel incontinence maybe

MRI (spine): r/o structural etiologies or demonstrate intrinsic inflammationLP: evaluate infectious or inflammatory etiology

Inflammation (e.g. transverse myelitis)InfarctionCompressionALS (degeneration of corticospinal tracts and anterior horn cells)

Cerebral Hemispheres/ Brainstem

Hemisphere:contralateral side in UMN patternParasagittal: contralateral leg Lateral hemisphere: arm and face Deep hemisphere (e.g. internal capsule): legs, arms, and faceBase of pons: ipsilateral face, contralateral arm, leg (crossed signs) b/c descending motor fibers to face have crossed at that level by those to body have not

Cognitive signs

Left hemisphere: aphasia, apraxia

Right hemisphere: neglect, visuospatial dysfunction

Brainstem: CN dysfunction

CT or MRI Stroke, demyelinating disease, traumatic injury, tumor, infection

THE SENSORY SYSTEM

Anatomy of Sensory Pathways

Modality Tract Somatotopic Arrangement

1st order neuron

2nd order neuron

3rd order neuron

Fiber type

Pain and temperature

Spinothalamic tract

SacralcervicalLateralmedial

Synapse at level of dorsal horn of spinal cord

Cross and travel contralaterally in STTTerminates in thalamus

Cortical projections to postcentral cortex

Thinly myelinated and unmyelinated slowly conducting fibers (A-delta and C)

Proprioception, vibration, light touch

Dorsal columns

Nucleus gracilisNucleus cuneatus

Medial lemniscus

LegsarmsMediallateral

LegsarmsLateralmedial

Travel ipsilaterally in dorsal column system reaching 2nd order neuron at level of medulla in nuclei gracilis and cuneatus

Axons from nuclei gracilis and cuneatus cross at lower medulla to form the medial lemniscus

Heavily-myelinated A-alpha and A-beta)

Facial sensation CNV Terminates in thalamus

Examining the Sensory System Touch wisp of cotton Pain pin Joint position sense/proprioception moving great toe up and down, moving object up or down on skin and asking pt

the direction of movement Vibration 128-Hz tuning fork applied to toes and other bony structures Temperature cold tuning fork

Sensory Abnormalities: Terms

Paresthesia Abnormal sensation described by pt as tingling, prickling, pins and needles, etc.Dysesthesia Unpleasant sensations triggered by painless stimuliHyperesthesia Increased sensitivity to sensory stimuliHypoesthesia Diminished sensitivity to sensory stimuliAllodynia Pain provoked by normally innocuous stimuliDissociated sensory loss

Loss of one of sensory systems w/ preservation of another one, e.g. in a central cord syndrome, you will get loss of pain and temperature (STT) w/ preservation of light touch, proprioception, and vibration sense (dorsal columns)

Negative symptoms Numbness, loss of cold/warm sensation, blindness, deafness (d/t disruption of nerve excitation)Positive symptoms Pain, paresthesias, visual sparkles, tinnitus (d/t excitation or disinhibition)

Approach to Pt with Sensory Loss

Recognize sensory abnormality by modality Judge level at which the abnormality is produced Establish a diff dx of pathologic processes that can affect the particular modality/sensory system Establish the cause: primary neurologic disease OR systemic disease

Patterns of Sensory Loss According to Localization

Site of Lesions Sensory Findings Other Neurologic Abnormalities

Examples

Peripheral nerve Loss of LT, T, PP, proprioception in influenced area

Associated weakness in muscles innervated by that nerve; distal muscle weakness, atrophy, areflexia

Peroneal neuropathyMedian and ulnar neuropathies

(LMN signs)Root Loss of all sensory modalities in a

dermatomal distributionWeakness in a myotomal distribution, atrophy, segmental hyporeflexia

L5 radiculopathyCervical radiculopathy

Plexus Sensory loss in distribution of 2 or more peripheral nerves

Muscle weakness that cannot be localized to a single nerve or root

Brachial plexopathy d/t trauma, inflammation, infiltration, etc.

Spinal cord Sensory level: bilateral loss of all sensory modalitiesSensory dissociationContralateral hypesthesia and ipsilateral loss of proprioception (Brown-Sequard syndrome)Proprioceptive loss and corticospinal tract involvementSaddle anesthesia

Paraplegia, tetraplegia; initially areflexia, then hyperreflexia below the lesion and Babinski sign (UMN signs)

Myelopathy

Central cord syndrome

Brown-Sequard syndrome

Brainstem Ipsilateral facial numbness and contralateral body numbness

Alternating hemiplegia; CN findings, INO, ataxia

Posterior circulation strokesTumor

Thalamus Hemibody anesthesia May have motor findings Lacunar strokeHemmorhage

Posterior limb of internal capsule

Hemibody anesthesia Hemiplegia Lacunar strokeHemorrhageTumor

Cortex All modalities affected on contralateral side

Sensory neglectAgraphesthesia

Parietal strokeHemorrhageAVM

Psychogenic Hyperesthesia for one modality in one area w/ anesthesia for another modality in same area; changing sensory findingsNonphysiologic sensory level changes (abrupt midline changes, vibration asymmetry over forehead)

Any Psychogenic (a diagnosis of exclusion)

VERTIGO AND DIZZINESS

“Dizziness” Vertigo: illusion or hallucination of movement that is usually rotatory, but may be linear Light-headedness: feeling faint, refers to presyncopal state Dysequilibrium: sensation of imbalance or unsteadiness usually referable to legs rather than to a feeling inside head

Vertigo D/t acute asymmetry of neural activity b/w L and R vestibular nuclei Does NOT result from slow unilateral loss of vestibular fxn (acoustic neuroma) or from symmetric bilateral loss of

fxn (ototoxic drugs) Approach to determining etiology

o Periodicity/duration of sxso Positional or spontaneous sxso Peripheral or central origin

Peripheral tinnitus, hearing loss; accompanying N/V more prominent Central diplopia, dysarthria, dysphagia, or other sxs of brainstem dysfunction; ability to walk or

maintain posture may be more impaired

Spontaneous Vertigo: Single prolonged episodeVestibular neuronitis Acute unilateral (complete or incomplete) peripheral vestibulopathy; sudden and spontaneous

onset of vertigo, N/V; onset over min-hrs, peak w/in 24 hrs, sxs improve gradually over several days/wks; nystagmust is strictly unilateral and may be suppressed by visual fixation; recovery represents central compensation for loss of peripheral vestibular fxn

Labyrinthine concussion Can result from head injury; vertigo sometimes accompanied by hearing loss and tinnitusInfarction of labyrinth, Blood supply to central/peripheral vestibular systems via vertebrobasilar system (posterior and

brainstem, or cerebellum inferior cerebellar aa. and superior cerebellar artery) and to inner ear via anterior inferior cerebellar artery (infarction of inner ear sudden onset of deafness or vertigo or both)Brainstem or cerebellar stroke most important diff dx in pts w/ suspected acute vestibular neuronitis; if a central-type nystagmus is present, then cerebellar or brainstem infarction w/ associated CN si/sx, weakness, ataxia, or sensory changes that clearly indicate a central process

Spontaneous vertigo: recurrent episodesMeniere’s disease Episodic vertigo w/ N/V; fluctuating, but progressive hearing loss, tinnitus, and a sensation of

fullness or pressure in ear; d/t an intermittent increase in endolymphatic volumePerilymph fistula D/t disruption of lining of endolymphatic system; pt reports hearing “pop” at time of a sudden

increase in middle ear pressure w/ sneezing, noseblowing, coughing, or straining, which is followed by abrupt onset of vertigo

MigrainePositional vertigo: peripheralBPPV (benign positional paroxysmal vertigo)

Episodes precipitated by changes in position such as turning over in bed or looking upward; attacks are brief (sec-min), and sxs typically begin after a few seconds’ latency following change in position; d/t freely moving Ca++ carbonate crystals w/in one of semicircular canals; when head is stationary, they settle in most dependent part of canal (posteriorly); w/ head movements, they move slower than endolymph w/in which they lie, and their inertia once the head comes to rest causes ongoing stimulation of the hair cells that results in the illusion of movement (vertigo); Dix-Hallpike test is diagnostic (downbeating and torsional nystagmus); Epley maneuver can be used to remove crystals from posterior canal

Syncope Transient LOC and postural tone d/t brain hypoperfusion

o Hypotension d/t cardiac dzo Low intravascular volumeo Excessive vasodilation

Presyncopal sxs include: light-headedness, HA, neck pain, blurring of vision, cognitive slowing, buckling of knees 2 neurologic varieties (both involve ANS dysfunction)

o Neurogenic syncope (more common): acute hypotension results from transient failure of ANS cardiovascular control; an acute hemodynamic rxn involving a reflex that is triggered by excessive afferent discharges from arterial (including heart and great vessels) or visceral mechanoreceptors; efferent impulses via vagus lead to cardio-inhibition and vasodepression that result in hypotension and bradycardia

Micturition syncope trigger is rapid emptying of distended bladder Carotid sinus hypersensitivity trigger is compression of carotid sinus Neurocardiogenic syncope vigorous contraction of an underfilled ventricle Vasovagal syncope trigger is strong emotions or pain

o Neurogenic orthostatic hypotension: d/t persistent ANS failure; d/t intravascular volume depletion (dehydration, Addison’s disease) or d/t inability to activate efferent SNS fibers appropriately upon assumption of the upright posture; the underlying pathology is either primary or secondary ANS failure (e.g. d/t diabetic ANS neuropathy), but the hallmark of both is failure to release noradrenaline upon standing; consider contribution of drugs such as diuretics, antihypertensives, vasodilators, and antidepressants; drug management to ameliorate sxs include midodrine and fludrocortisone

ATAXIA AND GAIT DISORDERS

Ataxia vs. Other Gait Disorders Ataxia: general term describing manifestations of dz of cerebellum or its connections Other: NOT ALL ataxia is cerebellar in origin, e.g. de-afferentation resulting from loss of position sense also results

in ataxia THUS: distinguish b/w cerebellar v. sensory ataxia

AtaxiasGeneral

Vermal lesions truncal/gait ataxia Hemispheric lesions ipsilateral limb ataxia

Si/Sx of Cerebellar Disease Dysmetria abnormality of range and force of movement; manifests as erratic, jerky movements w/ over- and

undershooting the target (limb or ocular dysmetria) Intention tremor rhythmic side-to-side oscillations of the limb as it approaches the target

Dysdiadochokinesia abnormality of rate and rhythm of movement demonstrated by rapid alternating movement test Gait ataxia broad-based and unsteady, w/ inability to walk in straight line and tendency to lurch from side to side Truncal ataxia impaired control of truncal posture; when severe, unable to even site unsupported Dysarthria slow scanning and monotonous speech Nystagmus

Diseases

Disease Etiology Characteristics Ass. Si/Sx Course + PrognosisCerebellar hemmorhage/ infarction

Hemorrhage/infarction Abrupt onset of vertigo, vomiting, inability to walk

Level of arousal may be depressed if 4th ventricle is compressed w/ hydrocephalus or if there is pressure on BS

Medical emergency

Postinfectious cerebellitis

Typical b/w ages 2-7 following varicella or viral infection

Acute onset of limb and gait ataxia, dysarthria; severity ranges from mild unsteadiness to inability to walk

Lasts a few weeks, recovery is usually complete

Episodic ataxias Inherited mutations in Ca++ and K+ channels

Brief episodes of ataxia, vertigo, N/V

Paraneoplastic cerebellar degeneration

Underlying gynecologic or small cell lung cancer

Acute/subacute onset of pancerebellar syndrome w/ truncal, gait, limb ataxia; dysarthria; ocular dysmetria and nystagmus

MRI usually normalAnti-Yo, anti-Hu autoantibodies in serum

Disease peaks in a period of weeks then stabilizes, leaving patient w/ profound disability

Alcoholic cerebellar degeneration

Long-standing alcohol abuse; most common cause of acquired cerebellar degeneration

Vermis bears brunt of damageprogressive gait and truncal ataxia evolving over wks-mo

Alcoholic polyneuropathy

Cessation of drinking and supplementation of nutrition offer the best (though limited) chance of improving

Friedrich’s ataxia AR, inherited, childhood onset

Progressive, affects arms>legs; severe dysarthria

Loss of reflexes, spasticity, extensor plantar responses, impaired vibration and position sense

AD spinocerebellar degenerations

AD, inherited, onset in young adult lifeD/t trinucleotide CAG expansion

Insidious onset of progressive impairment of gat and dysarthria in young adult life

Mild to moderate cognitive decline is a late feature

Miller-Fisher Syndrome

Variant of Guillain-Barre syndrome (mediated by post-infectious immune process)

Triad of ataxia, areflexia, ophthalmoplegia

IgG anti-GQ1b antibodies in serum of >90%

Self-limitingUsually full recovery

Gait Disorders

Gait Disorder Anatomical Location

Description Pathology

Hemiplegic BrainstemCerebral hemisphere

Affected leg is stiff and does not flex at hip; leg is circumducted, w/ tendency to scrape floor w/ toes; arm is held in flexion and adduction and does not swing freely; the spastic (paraparetic) gait is

Stroke, tumor, trauma

Paraplegic Spinal cord

Bihemispheral

essentially that of a bilateral hemiplegia; adductor tone is increased, and legs tend to cross during walking (scissoring gait)

Demylination (MS), transverse myelitis, compressive myelopathy

Diffuse anoxic injuryAkinetic-rigid Basal ganglia Stooped posture; narrow-based, slow, shuffling gait w/

small steps and reduced arm swing; arms carried flexed and slightly ahead of body; difficulty w/ gait initiation; postural reflexes are impaired and pt may take series of rapid small steps (festination) forward (propulsion) or backward (retropulsion) in an effort to preserve equlibrium

Parkinson’s Disease

Frontal Frontal lobes

Subcortical

Flexed posture; feet may be slightly apart; gait initiation is impaired, and word “magnetic” describes difficulty lifting feet off ground; pt advances w/ small, shuffling, and hesitant steps; w/ increasing severity, pt may make abortive stepping movements in one place w/o ability to move forward

Hydrocephalus, tumor, stroke, neurodegenerative d/o

Binswanger’s disease

Waddling Hip-girdle weakness

Muscular dystrophy, spi9nal muscular atrophy, acquired proximal myopathy

Sensory Ataxia (Slapping)

Large-fiber neuropathy

Dorsal columns

D/t loss of proprioceptive input from feet; cautious, wide-based gait; slow steps; contact w/ ground is made by heel and forefoot then strikes floor w/ a slapping sound (slapping gait); walking on uneven surfaces or in dark is especially difficult

Vitamin B12 deficiency

Tabes dorsalis

URINARY AND SEXUAL DYSFUNCTIONURINARYAnatomy/Physiology of Continence

Circuit Connections FunctionCircuit 1 Dorsomedial frontal lobe to M region (pons) Volitional control of micturitionCircuit 2 (spino-bulbar-spinal)

Reflex arc starting in bladder projecting to M region (pons) w/ outflow connections to PNS sacral spinal motor nuclei

Circuit 3 Spinal segmental reflex arc w/ afferents from detrusor muscle to pudendal nucleus and efferent fibers to striated sphincter muscles

Pontine micturition centero Areas

M region stimulation decrease in urethral pressure, then rise in detrusor muscle pressure and voiding; M region projects to sacral cord IML

L region (same level) stimulation contraction of urethral sphincter (storage)o Damage loss of inhibitory control over spinal reflexes (circuit 3) and as bladder distends, micturition reflex

is automatically activated w/o pt’s awareness or control, and detrusor hyperreflexia and incontinence occurs Muscles of micturition

o Detrusor (smooth): PNS causes contraction; during filling it is inhibited, during micturition it is stimulatedo Internal urethral sphincter (smooth): SNS causes contraction; stim during filling, inh during micturitiono External urethral sphincter (skeletal): Somatic motor causes contraction; stim during filling, inh during mic

Evaluation of IncontinenceUrodynamic studies

PVR (postvoid residual): normal<50mL; if increased implies poor bladder emptying (sphincter dyssynergia, atonic bladder are common neurogenic causes)

Cystometry: gives info re bladder compliance, capacity, volume at 1st sensation and at urge to void; voiding pressure; presence of uninhibited detrusor contractions

Cystourethroscopy: assesses integrity of lower urinary system, and IDs important urethral and bladder lesions Retrograde urethrography

Neurophysiologic studies: sphincter and pelvic floor EMG

Type of neurogenic bladder

Capacity Compliance Other Indicates…

Spastic bladder Decreased Reduced Uninhibited detrusor contractions

UMN problem d/t frontal lobe, pontine, or suprasacral spinal cord lesion

Atonic bladder Increased Increased Low voiding pressure and flow rate

LMN problem d/t lesion at level of conus medullaris, cauda equina, or sacral plexus, or peripheral nerve dysfunction

Type of incontinence

Description Etiology Clinical expression

Patient population

Associated si/sx

Urge Involuntary loss of urine a/w strong desire to void (urgency)

Detrusor instability (DI) Detrusor hyperreflexia (if DI d/t neurologic problem)

Spastic bladder

Strokes, suprasacral spinal cord lesions, MS

Detrusor-sphincter dyssynergia (DSD): inappropriate contraction of external sphincter w/ detrusor contraction urinary retention, vesicourethral reflux, and renal damage

Stress Involuntary loss of urine during coughing, sneezing, laughing, or activities that increase intra-abdominal pressure

Weak pelvic floor muscles

Multiparous women

Mixed Urge + stressOverflow Involuntary loss of

urine a/w overdistension of bladder; constant dribbling

Underactive or acontractile detrusor (drugs, diabetic neuropathy, lower spinal cord injury, or radical pelvic surgery that interrups innervation of detrusor)

Atonic bladder

Incontinence in the Neurologic Patient Stroke and spinal cord disease usually produce an UMN bladder or spastic bladder w/ or w/o sphincter dyssynergia

o Supraspinal dz Stroke Parkinson’s (40-70%)

o Spinal cord dz Spinal cord injury Multiple sclerosis (75%)

Small-fiber neuropathies can produce a neurogenic atonic bladder w/ high PVR (risk to upper urinary tract), e.g. as in diabetic neuropathy

Treatment of Urinary IncontinenceGoals

Preservation of upper urinary tract fxn Improvement of pt’s urinary symptoms that impair quality of life

Treatments

Disorder Treatments

Urge incontinence (spastic bladder) 1. Anticholinergic agents: Tolterodine (Detrol), Oxybutynin (Ditropan), Propantheline2. TCAs: imipramine3. Desmopressin spray/tabs (DDAVP): used to treat diabetes insipidus, but produces a significant reduction in voiding frequency4. Intravesical capsaicin: for intractable detrusor hyperreflexia; has neurotoxic effect on afferent C fibers that drive volume-determined reflex detrusor contractions

Stress incontinence 1. Alpha-adrenergic agonist drugs: Phenylpropanolamine, Pseudoephedrine (these stimulate smooth muscle alpha-adrenergic receptors contraction)2. Estrogen therapy: adjunctive in post-menopausal women

Atonic bladder w/ overflow incontinence

1. Crede’s maneuver or valsalva maneuver to empty bladder2. Intermittent self-catheterization (mainstay of long-term tx)3. Pharmacotherapy usually not effective; cholinergic agent bethanecol (stimulates cholinergic receptors, increasing detrusor muscle tone

Detrusor dyssynergia 1. Intermittent catheterization2. Suprapubic catheterizaition3. Sacral nerve stimulation

ERECTILE DYSFUNCTION Persistent inability to attain or maintain penile erection sufficient for sexual intercourse 10-20 million American men affected 80% of cases are biologic or organic in origin

Anatomy and Physiology Pudendal nerve: carries motor and sensory fibers that innervate the penis and clitoris PNS:

o Sacral cord S2-S4, erectiono Local mediators: NO, cGMP primarily released by PNS activity contributing to sustained erection

SNS: cells in spinal cord levels T11-T12 through hypogastric plexus, ejaculation

Management Requires recognizing etiology (neurogenic, vascular, traumatic, endocrine, psychogenic, drugs) and treating

underlying cause Pharmacotherapy:

o Viagra (25-100 mg/day, 30-60 min before intercourse): SE include facial flushing, HAo Intraurethral suppositorieso Intracavernosal injections of alprostadil (Caverject)

HEADACHE AND FACIAL PAIN

Pathophysiology Caused by disturbance/irritation of pain-sensitive structures in head

o W/in cranium: blood vessels, meninges, CN V, IX, X (brain parenchyma itself + bone are pain-insensitive)o Outside cranium: periosteum of skull, muscles, nerves, vessels, subcutaneous tissues, eyes, ears, sinuses,

mucus membranes Pain pathway

o Irritation of pain-sensitive structure nociceptive input relayed to brain via CN V or upper cervical roots CNV: dermatomal distribution on face, anterior and middle cranial fossas (thus, painful stimulation

of structures in ant/mid fossas referred to eye or front or side of head) Upper cervical roots: dermatomal on posterior surface of head and neck and ears, posterior fossa

(thus, painful stimulation of structures in posterior fossa referred to back of head and upper part of neck)

3 General Classes of HAs Primary (migraine, cluster, tension) not a/w underlying structural cause HA a/w serious neurologic dz (brain tumor, meningitis, aneurysm) HA/pain from structures in skull and face (eyes, sinuses, mouth)

History of the Presenting HA

Hx Component ExampleOnset and frequency of painLocation of pain Unilateral cluster, migraine

Bilateral tension+/- prodromal symptoms? Scintillating scotoma prior to classic migraine Precipitating factors Alcohol as a trigger for cluster

Nitrite-containing food (hot dog/salami), tyramine-containing cheese as migraine triggerDescription of pain Lancinating/shooting pain in V2/V3 distribution trigeminal neuralgia (tic douloureux)

Unilateral throbbing pain migraineDull, bandlike or tightening pain tension Sharp, stabbing pain esp. behind one eye cluster

Associated sx/neurologic signs N/V migraine, increased ICP d/t hydrocephalus or tumorPhotophobia, phonophobia, increased frequency of HA at menstruation migraineFever meningitis, local infection such as dental abscessUnilateral lacrimation or rhinorrhea cluster

Primary Headaches

Primary HA Type Male-Female Ratio

Age of Onset

Type of Pain Associated Si/Sx Treatment

Migraine

(w/ aura= ”classic”) (w/o aura= ”common”)

F>M Teen years

Unilateral or bilateral, pulsing or throbbing

N/V, photophobia, phonophobiaAura is a transient focal neuro sx preceding HA; most common type is visual (flashing lights, zigzag lines marching across visual field); develop over 5-20 min, and last 15 min-1 hr; HA usually follows w/in 20-60 min and lasts 4-72 hrs

Prophylaxis: avoid triggers, meds (beta-blockers like propranolol, Ca++ channel blockers like verapamil, TCAs like amitriptyline, some anticonvulsants like depakote)Abortive: simple analgesics like acetominophen, aspirin, NSAIDS, ergot alkaloids and selective 5-HT1 agonists like sumatriptan

Tension F=M Any age

Bilateral and occipital; pain is dull and bandlike, not throbbing

Muscle spasm may be involved

Many of those used for migraineAlso, PT, stress management, biofeedback, psychotherapy

Cluster M>>F 3rd decade of life

HAs occur in clusters in which HA recur cyclically (3-4x/day per cluster) followed by remission; each cluster lasts up to several months and remission can be mo-yrsPain behind one eye or over lateral part of nose

Ipsilateral conjunctival injection, lacrimation, nasal congestion, and occasional Horner’s syndrome

Avoid possible precipitants (e.g. EtOH, strenuous exercise)Verapamil for prophylaxisSymptomatic tx includes inhalation of pure oxygen (>90% effective); sumatriptan and dihydroergotamine can be used too

Secondary HAs

HA Type Etiology Description Associated Si/Sx Diagnosis TreatmentSubarachnoid Hemorrhage

Nontraumatic: ruptured aneurysm, bleeding from A-V malformation

Sudden, severe, “worst HA of my life”

LOC, vomiting, neck stiffness

LP or CT: look for evidence of hemorrhage or heme b/d in CSF

Acute control of BP for adequate brain perfusion, monitoring for vasospasm and acute obstructive hydrocephalus d/t

subarachnoid bloodDefinitive tx: surgical resection or clipping of aneurysm

Temporal Arteritis(Giant Cell Arteritis)

Subacute granulomatous inflammatory condition involving branches of external carotid artery, esp. temporal arteries

Occurs in elderly, unilateral or bilateral, over temporal arteries

Scalp tenderness, jaw pain during chewing (jaw claudication), involvement of ophthalmic artery can lead to blindness

Elevated ESR to 100Definitive dx made by temporal artery biopsy demonstrating vasculitis

Prednisone in decreasing doses for several months and then continued for next 1-2 yrs

Trigeminal Neuralgia (Tic Douloureux)

Microvascular compression of trigeminal nerve

Facial pain syndrome in which brief severe electrical shock-like pains occur in distribution of a branch of CNV (2 and 3 most common); most common in middle age and elderly; can be precipitated by movement, a cold breeze, or tactile stimulation in a trigger zone

Carbamazepine

Idiopathic Intracranial HTN (Pseudotumor Cerebri)

A/w obesity Women in 2-4th decades of life

Bilateral visual sxs: fleeting loss of visual acuity, scotoma, double vision, perhaps papilledemaCT/MRI normalLP shows increased pressure >250 mm water

Acetazolamide (CA inhibitor): inhibits CSF formationFurosemideOral steroidsSerial LP to decrease CSF pressureIf tx is ineffective, pts may be left w/ permanent visual loss

Post-Lumbar Puncture or Low-Pressure HA

Following LP HA in an upright position starting w/in 48 hrs of LP and resolving in several days w/o tx; HA relieved when lying down

IV caffeine sodium benzoateBlood patch