CNS structures (Names)

Cerebrum

Cerebellum

Brain Stem

Diencephalon

Basal Ganglia

Spinal Cord

Structures of the Diencephalon

Thalamus

Hypothalamus

Epithalamus

Subthalamus

Basal Ganglia 

Caudate Nucleus

Globus Pallidus

Putamen

Claustrum

Amygdala

Pathway

A chain of communicating neurons inside or outside of the CNS.

Tract, fasciculus, peduncle, lemniscus

Bundle of pathway axons in the CNS

Frontal lobe

Parietal lobe

Occipital lobe

Temporal lobe

Sulci (large)

Fissures (small)

Midbrain

Pons

Medulla

Two internal carotid arteries

Two vertebral arteries

At level of pons:  basilar artery

At level of cerebrum: posterior cerebral artery

Internal carotid artery branches into anterior cerebral artery (midline area of anterior cerebrum) and middle cerebral artery (lateral surface of the anterior cerebrum).  

Anterior --> midline

Middle --> lateral  

• Affects circulation to the visual area of the cerebrum, cerebellum and brain stem

• Visual loss, dizziness, other problems. 

Disintegration of cell membrane

Disintegration of axon itself

Accumulation of granular debris

Muscular atrophy in muscle supplied by the damaged nerve.

DM

ETOH

HIV

Leprosy (most common cause worldwide)

Unilateral Facial Paresis. LMN.  Abrupt onset which may worsen over a day or two.  Hyperacusis (super sensitive hearing to certain frequencies) or impaired taste may occur.  Face feels stiff and pulled to one side.  Ipsilateral restriction of eye closure.  Difficulty eating/drinking.  Flat nasolabial fold, ipsilateral sagging of mouth angle resulting in drooling, inability to wrinkle forehead symmetrically or raise ipsilateral eyebrow. 

60% of cases recover w/o tx.  Only 10% have permanent disfigurement or other long-term sequelae.  If palsy is v. severe in first few days, can predict unsatisfactory outcome.  No real tx for most. Corticosteroids initiated in first 5 days in severe cases.  Protect eye w/ lubricating drops (lubricating ointment @ night), patch if eye closure not possible.  

Loss of sensation in "stocking-glove" pattern with longer nerves being more vulnerable.  Usu bilateral, symmetric  and assoc w/dulled perception of vibration, pain and temp.  Pain can be mild or severe.  Sensory deficit may eventually prevent any pain sensation. 

General, nonspecific term used to describe a wide range of dzs affecting the PNS.  Common but complex.  

Cranial Nerves (except CN II: Optic)

Spinal nerve roots

Dorsal root ganglia

Peripheral nerve trunks and branches

Peripheral autonomic nervous system

Dz affecting many nerve fibers:  Can be sensory, motor or autonomic nerve pathways. 

Acquired: DM & AIDS

Hereditary: Charcot-Marie-Tooth Dz (motor and sensory)

Dz affecting one nerve fiber such as:

Carpal tunnel syndrome: median n.

Trigeminal neuralgia

Dz affecting one nerve fiber such as:

Carpal tunnel syndrome: median n.

Trigeminal neuralgis

Auto immune, inflammatory polyneuropathy that attacks gangliosides and damages myelin.  Multiple nerves are affected.  Usu 2º viral illness.

Type of nerve damage that is usu 2º diabetes (DM).

Primary dz site: neuronal cell bodies

Degeneration goes slowly

First occurs distally then progresses centrally

Sometimes follows infective illness, inoculations or surgical procedures.  Campylobacter jejuni enteririts. • Rapid onset  •Main complaint: weakness which varies widely and has proximal emphasis w/ symmetric distribution.  • Usu begins in lower extremities (LE), sometimes spreading to arma and possibly face.  • Mm of respiration & deglutition (swallowing) may be affected. • Sensory sx < affected than motor but distal paresthesias and dysethesias are common.   Neuropathic or radicular pain is present in many. • ANS sx common: may be severe: tchycardia, cardiac irreg, hypo- or hyper- tension, fcial flushing, abn of sweating, pulmonary dysfunction, impaired sphincter control.  

CSF characteristically contains high protein concentration with a normal cell content: may take 2-3 weeks to develop.  • Electrophysiologic sudies may reveal marked abn  •  Patho exam shows primary demyelination or axonal degeneration.

Prednisone is ineffective/ may prolong recovery time.  • Plasmapheresis is of value:  esp in first few days and in severe cases • IVIG (intravenous immunoglobulin) is helpful and imposes less stress than plasmapheresis • Chest PT to prevent atelectasis • Marked hypotension may respond to volume replacement or pressor agents.  • Low dose heparin to prevent pulmonary embolism shoud be  considered •Antiepileptic agents and TCAs often used to tx neuropathic pain (Phenothiazine/Prolixin in combo w/TCA used to manage chronic pain syndropmes • Small local areas:  lidocaine and capsaicin • Avoid narcotics • Gabapentin (Neurontin) sx tx of painful neuropathy •TCA:  Amitriptyline (Elavil, Endep) for pain relief • Analgesic: Tramadol • NSAIDs: sulindac and IB.  Not for monotherapy: adjuvant role for short-term pain relief (if pnt has low risk of GI bleed and renal dysfunction) • Pregabalin (Lyrica) if burning, neuropathic pain.  ADRx can be problematic

Auto immune, inflammatory  attacks gangliosides and damages myelin.  Multiple nerves are affected.  Usu 2º viral illness.

•  All pnts are referred, all pnts are admitted •  80% make full recovery but it may take many months.  • 20 % are left with persisting disability

Lesion is at neuromuscular junction

Fluctuating weakenss of commonly used boluntary mm, producting sx such as diplopia, ptosis, difficulty swallowing, limb weakness, or some combo of these.   • Activity increases weakness of affected mm: sx fluctuate during the day.  Diurnal variation is superimposed on a tendency to longer-term spontaneous relapses & remissions that may last for weeks.  • Weakness may remain localized to a few m groups, wesp ocular mm or may become generalized. • Disorder follows a slowly progressive cours and may have a fatal outcome owing to respiratory complications such as aspiration pneumonia.  • Sensation usu normal, no reflex changes.

DX usu confirmed 2º response to short-acting cholinesterase.  Edrophonium 10 mg IV (2 mg initially then 8 mg after 30 mins) provides obvious improvement in strength of weak mm x5 mins.  • EMG indicates disturbance of NM transmission. • Assay of serum for elevated levels of circulation acetylcholine receptor antibodies has a sensitivity of 80-90% 

Short-acting cholinesterases transiently improve the weakness. Sympotomatic tx, does not alter dz course • Aminoglycosides may exacerbate  and should be avoided  • Thymectomy usu leads to sx benefit or remission and should be considered in all pnts under 60 y.o.  •  Initial high dose corticosteroids taperd to a relatively low maintenance dose:  total withdrawal is difficult.  •  In pnts w/ major disability: plasmapheresis or IVIG (IV immunoglobulin) may be beneficial or to stabilize pnts prior to thyrectomy or to manage acute crisis. 

Affects primarily middle aged men.  Pathophys unclear but may be 2º activation of cells in the ipsilateral hypothalamus, triggering trigeminal autonomic vascular system.  • Often no family hx of HA or migraine

Oral drugs usu unsatisfactory • Sub-q or intranasal sumatriptan • inhalation of 100% O2 (via rebreather) may be effective.  • Zolmitiriptan (5- & 10-mg nasal spray)  • Dihydroergotamine (0.5-1 mg) • Viscous lidocaine intranasally • Various prophylactic agents:  cyproheptadie, lithium carbonate, verapamil, topiramate, valproate, methysergide

Episodes of severe unilateral periorbital pain occur daily for several weeks and are often accompanied by: ipsilateral nasal congestion, rhinorrhea, lacrimation, redness of the eye, Horner syndrome.  • During attacks, pnt is usu quite restless/agitated.  • Attacks usu @ night, awaken pnt and last 15 mins to 3º  then spontaneous remission x weeks or months before another bout of closely spaced ttacks occurs.  • Bouts last 4-8 wks and occur upto several times/year. • May be triggered 2º ETOH, stress, glare, specific foods

Usu no abnormality other than Horner syndrome.  Can be transient during attacks or persistent. 

Pnts often give family hx of (it).  • Attacks may be triggered by emotional or physical stress, lack or excess of sleep • missed meals • specific foods (eg chocolate) • ETOH • bright lights • loud noise • menstruation • use of oral contaceptives.

Pain usu pulsatile;   typically, though not always, unilateral. • N/V, photophobia, phonophobia are common •there may be transient neurologic sx (usu visual) preceding  • may be lateralized or generalized • dull or throbbing • sometimes assoc with anorexia, osmophobia (fear, aversion or psychologic hypersensitivity to smells) • Usu build up gradually and may last for several hours or longer • Focal disturbances of neuro function may precede or accompany • May be attributed to constriction of internal carotid branches.  • Visual distrubances occur commonly and may consist of field defects, luminous visual hallucinations (stars, sparks, unformed light flashes), geometric patterns, zigzags of light or some combo of visual field defect and luminous hallucinations (scinitillating scotomas).  • Aphasia, numbness, paresthesias, clumsiness, dysarthria, disequilibrium, or weakness.

Avoidance of any percipitating factors, together with prophylactic or symptomatic pharmacological tx if necessary.  • Sx Tx: rest in a quiet, darkened room.  Simple analgesic (ASA, acetominophen, IB, naproxen) taken right away often provides relief but tx w/prescription tx is sometimes necessary.  • Prevent medication overuse:  limit to 15d/month or less.  Combo analgesics 10d/month or less. • Cafergot (Ergotamine and caffeine) taken at start of sx or aura and q 30 mins prn ≤ 6 tabs/attack and ≤10/month.  If vomiting is a problem:  dispense suppositories or IV•  Sumatriptan (sub-q) is rapidly effective for aborting attacks.  Also avail in nasal form as well as oral.  • Other -triptans also available.  May cause N/V.  Contraindicated in pnts w/coronary or peripheral vascular dz. •  Others also avail.  •Preventive may be necessary if more freq than 2-3x/wk.  Propranolol, amyltriptyline, imipramine, sertraline, fluoxetine, yproheptadine, Cliniine, Verapamil. 

Imaging studies have revealed changes in brainstem regions involved in sensory modulation , suggesting (it) relates to a failure of normal sensory processing. • Before or simultaneous with sx onset, regional cerebral blood flow is decreased in the cortex corresponding to the clinically affected area;  after 1 to several hours, hyeremia occurs in this same region. 

Pnts often give family hx of (it).  • Attacks may be triggered by emotional or physical stress, lack or excess of sleep • missed meals • specific foods (eg chocolate) • ETOH • bright lights • loud noise • menstruation • use of oral contaceptives. •Patho is probably 2º neurovascular dysfunction.  Dilatation of blood vessels innervated  by trigeminal nerve (CN V) 2º release of neuropeptides from pararsympathetic nerve fibers approximating these vessels.  • Probable underlying mechanism is activation of trigeminal raphe nucleus, nucleus tractus solitarius and dorsal raphe nucleus. •Onset: adolescent or early adult life. 

Neuro or somatic disturbance becomes sole manifestation of an attack (not pain)

Pnts freq c/o pericranial tenderness, poor concentration, other vague nonspecific symptoms and daily, vise-like or tight in quality but are not pulsatile.  • May be exacerbated by emotional stress, fatigue, noise, or glare. • Usu generalized, may be most intense: neck and back of head • Not assoc w/ focal neuro sx. 

Simple analgesics • If not effective: trial of prescription drugs • Techniques to induce relaxation include: massage, hot baths, biofeedback.• Exploration of causes of chronic anxiety.• Infreq local injection of botulinum toxin type A. 

Most common type of primary HA disorder.  

Often unnecessary • If necessary 2º disability, propranolol may be helpful but will need to be continued indefinitely. • May be used intermittently if (it)  is worse in predictable situations • If propranolol not effective, may try primadone • Next line options inc:  alprazolam, clozapine, topiramate, gabapentin, mirtazapine, levetiracetam.  • Botulinum toxin may reduce, but adverse effects include m. weakness.   • If disabling and unresponsive to other tx, contralateral thalamotomy or unilateral high-frequency thalamic stimulation 

May begin at any age and is enhanced by emotional stress. •  Usu involves one or both hands, head, or head and hands.  • Legs tend to be spared • ETOH  in small quantities commonly provides remarkable but short-lived relief. • Becomes more conspicuous w/time, leads to little disability • Speech may be affected if laryngeal mm are involved. 

Amantadine

Anticholinergic drugs

Levodopa

Dopamine Agonists

Selective MAOI

COMT inhibitor

Atypical antipsychotics

Used with mild sx but no disability.  • Improves all clinical features of  disorder.

What class of drugs is helpful in alleviating tremor and rigidity but not so good with bradykinesia & in what disorder?

Rasagiline, a selective MOA B inhibitor has a clear sx benefit in a daily oral dose of 1 mg, taken in the a.m.  also used for adjunctive tx in pnts w/response fluctuations to levodopa.  Slows progression of dz.

  Reduce metabolism of levodopa to 3-O-methyldopa and thereby alters plasma pharmacokinetics of levodopa, leading to more sustained plasma levels and more constant constant dopaminergic stimulation of the brain.  Tolcapone and entacapone are currently available and may be used as adjunct to levodopa-carbidopa in pnts w/response fluctuations

Confusion and psychotic sx, which may be iatrogenic, often respond to (this class of drugs) in (this disorder). 

Tremor, rigidity, bradykinesia, postrural instability are cardinal features.   • May also be mild decline in intellectual function • Tremor of 4-6 cycles per second most conspicuous @ rest • Enhanced 2º emotional stress • less severe during voluntary activity • Usu confined to one limb or to the limbs on one side for months to years before becomes more generalized.  • Flexed posture 2º rigidity • Bradykinesia is most disabling of sx.  • Effective voluntary movement may be regained during an emergency. •Relatively immobile face and widened palpebral fissures, infrequent blinking, certain fixity of facial expression.  • Seborrhea of scalp and face is common • Repetitive tapping (2x/second) over bridge of nose produces sustained blink response (Myerson sign)  •  Drooling • Soft, poorly modulated voice • variable rest tremor and rigidity in some or all limbs, slowness of voluntary movements • Typically no muscle weakness or tendon reflex alteration or plantar responses • Difficult for pnt to arise from sitting and begin walking • Gait: small shuffling steps, lack of normal automatic arm swing.  • Unsteadiness on turning, difficulty in stopping, tendency to fall.

• Consciousness is preserved during the ictal phase

• Clinical and EEG evidence of alteration of function in a relatively limited area ot the cerebral hemisphere.  AKA 'focal' or 'local', only part of cerebral cortex is excited.

Altered consciousness during a partial seizure.  • Impaired consciousness = "inablility to respond normally to exogenous stimuli by virtue of altered awareness or responsiveness" • May be self-limiting or may progress to greater cerebral involvement. 

TBI, CNS infections, febrile convulsions, other episodes of LOC (loss of consciousness)

Ethosuximide, Valproic acid, Clonazepam

Impairment of consciousness, sometimes w/mild clonic, tonic or atonic components (eg enuresis). • Onset and termination of attacks are abrupt • Impairment of external awareness is so brief that the pnt is unaware of it.  • Almost always begin in childhood and frequently cease by age 20 •  On EEG, assoc with bursts of bilat synchronous and symmetric 3-Hz spike and wave activity

Pnt may behave in abnormal fashion in immed postictal  period, w/o subsequent memory of events (postictal automatism).

After a seizure, a new seizure w/o pnt regaining consciousness.

Consist of single or multiple myoclonic jerks. 

Characterized by sudden loss of consciousness. • Pnt becomes rigid and falls to the ground • Respiration is arrested • Tonic phase usu lasts for less than a minute, followed by a clonic phase in which there is jerking of the body musculature that may last for 2-3 minutes and is then followed by a stage of flaccid coma. • Tongue or lips may be bitten, urinary or fecal incontinence may occur and pnt may be injured. • Immed after seizure pnt may either recover consciousness, drift into sleep or have further convulsion w/o recovery of consciousness b/t attacks (status epilepticus), recover consciousness and then have another seizure (serial seizure).  • HA, disorientation, confusion, drowsiness, nausea, m. soreness, or some combo of these is common postictally. 

Valproic acid 1500-2000 mg tid,

Clonazepam 0.04-0.2 mg/kg bid

Phenytoin 200-400 mg qd,

Carbamazepine (extended release) 600-1200 mg 2-3x/d,

Valproic acid1500-2000mg 2-3x/d,

Phenobarbital 100-200 mg qd,

Primidone 750-1500 mg tid,

Lamotrigine 100-500 mg bid,

Topiramate 200-400 mg bid,

Oxcarbazepine 900-1800 mg bid,

Levetiracetam 1000-3000 mg bid,

Zonisamide 200-600 mg qd, 

Tiagabine 32-56 mg bid,

Pregabalin 150-300 mg bid,

Gabapentin 900-3600 mg tid,

Felbamate 1200-3600 mg tid

Onset is abrupt & w/o warning.  Recovery usu occurs rapidly, often w/i a few mins. • If in carotid: common sx=weakness, heaviness of contralateral  arm, leg, face, singly or in combo.  • Numbness or paresthesias: solely or in combo • May be slowness of movement, dysphasia, monocular visual loss contralateral to affected limbs

Weakness

Clumsiness

Sensory Loss (vibration, proprioception, stereognosis)

All in Contralateral Lower Extremity

Abulia (lack of initiative)

Frank confusion

Poss urinary incontinence

Artery comes off of the internal carotid.  

Internal carotid bifurcates into anterior cerebral artery and middle cerebral artery.

Hemiparesis of contralateral face and arm

Hemisensory loss of contralateral face and arm (same distribution as motor loss)

Homonymous Hemianopia (visual field defect of either 2 right or 2 left halves of both eyes)

Aphasia (if on left)mainly expressive:  Broca's

• Hemanopia (1/2 of visual field is out) or

• Quadrantanopia (1/4 of visual field is out)  with macular sparing

• Contralateral hemiplegia with possible dysmetria, cerebellar ataxia, tremor

• Many Cranial Nerve III palsies

• Diplopia

• Cranial Nerve signs

• Bilateral motor and sensory signs

• Ataxia (lack of m coordination during voluntary movements inc speech, eyes movements and ability to swallow)

• Vertigo

• Facial weakness or palsy (Ipsilateral)

LOC is not immediate

Worst HA of my life

Nuccal rigidity (stiff neck)

This type of stroke in cerebellar basilar area is usu fatal

What type of stroke:

• Involves a single vascular territory

• Pnt may improve early in course of event

• Most extreme sx are at time of event 

• Initially may seemingly affect other areas but this is due to local swelling-sx resolve as swelling decreases.

CT w/o contrast for immed eval

Intracerebral hemorrhages

Subdural hematomas

Subarachnoid hemorrhages (most)

• (This test is) Superior to CT for small infarcts especially in posterior or vertebrobasilar circulation 

• Test that will see deep, subcortical infarcts

Territory supplied by Carotid Artery

Internal Carotid Artery

Anterior Cerebral Artery 

Middle Cerebral Artery

Vertebral Artery

Basilar Artery

Posterior Cerebral Arteries

• Vertigo and Dysarthria

•  Carotid artery stenosis or A-fib

• Cardiac disorders

• Large vessel, cardiocervical occlusive dz

• Small vessel, intracranial occlusive dz

• Hematologic disorders

• Embolus from proximal artery or heart

• Artherosclerotic dz of carotid artery @ carotid bifurcation:  common cause of carotid artery bifurcation

• 20% of ischemic strokes and TIAs are from cardiac emboli

Systemic panarteritis affecting medium & large vessels in pnts >50.  •  Thoracic aortic aneurysms occur 17x more frequently in pnts with arteritis, typically occuring ~7 years s/p arteritis dx is made.

HA, scalp tenderness, visual sx (amaurosis fugax or diplopia), jaw claudication, throat pain.  • Temporal artery may be nodular, enlarged, tender or pulseless.  Blindness may be 2º occlusive arteritis of posterior ciliary branch of ophthalmic artery.  • asymmetry of pulses in the arms, aortic regurg murmur, bruits 2º subclavian artery stenoses (indicates arteritis has affected aorta or maj branches)• Fever of unk origin can be upto 40º C (104ºF) w/rigors & sweats.  Normal WBC • C/o vague pain in tongue, nose, ears.

Slam it with steroids!  Fast!  • Prednisone 60 mg/d p.o. x1 month then taper • if pnt presents w/blindness: IV pulse methylprednisone 1g/d x3d.  • ASA 81 mg/d p.o.

Nearly 90% of pnts have ESRs >50mm/h.  (erythrocyte sedimentation rate). • Temporal artery biopsy emergently.

HA, confusion, somnolence, seizures, and focal deficits occur several hours after injury and lead to coma, respiratory depression and death unless tx'd by surgical evacuation 

Hematoma from tear in veins from cortex to superior sagittal sinus or gom cerebral laceration, visible on CT scan.

• Slowness, drowsiness, HA, confusion, memory disturbances, personality change, poss. dementia.  

• Focal neurologic deficits such as hemiparesis, hemisensory disturbances.

In many elderly persons there is no hx of trauma but in other cases a head injury, often trivial, preceded th onset of sx by several wks.  Late complications of head injury may include posttraumatic seizure disorder and posttraumatic HA. 

Diplopia

CN signs

BILAT motor and sensory signs

Ataxia

Vertigo

IPSILATERAL facial weakness or palsy 

Parkinsons

Huntingtons

Either a sensation of motion when there is no motion or an exaggerated sense of motion in response to a given bodily movement.

 FR 56.   Part of brain stem that mediates papillary reflexes and eye movements

(Curr 308)