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Diseases of the Nervous SystemDiseases of the Nervous System

Central nervous systemCentral nervous systemBrain is a prisonerBrain is a prisonerBasic cellular elementsBasic cellular elements

Neurons, location means everythingNeurons, location means everythingNeuronal reaction to injury, very limitedNeuronal reaction to injury, very limited

Axonal growthAxonal growthNo regeneration of lost cellsNo regeneration of lost cellsAccumulation of junk within the cells can be harmful.Accumulation of junk within the cells can be harmful.

Glial component, supportiveGlial component, supportiveMicroglia, the police force of the CNSMicroglia, the police force of the CNSAstrocytes, structural like fibroblasts elsewhereAstrocytes, structural like fibroblasts elsewhere

Gemistocytes are reactive astrocytesGemistocytes are reactive astrocytesOligodendrocytes, make myelin (the insulation)Oligodendrocytes, make myelin (the insulation)

MeningesMeninges

Cerebral EdemaCerebral Edema

Injury to brainInjury to brainTumorTumorRubor……Rubor……

Swelling can’t go Swelling can’t go anywhereanywhereCompression of vital Compression of vital structuresstructuresHerniationHerniation

SublaxSublaxTranstentorialTranstentorialCerebellar tonsilsCerebellar tonsils

Brainstem HemorrhagesBrainstem Hemorrhages CSF FlowCSF Flow

Made in the ventriclesMade in the ventriclesFlows down aqueductFlows down aqueductInto 4Into 4thth ventricleventricleOut into the Out into the subarachnoid spacesubarachnoid spaceUp to the arachnoid Up to the arachnoid granulationsgranulationsBack into the bloodBack into the bloodObstructions in Obstructions in movement will lead to movement will lead to hydrocehpalushydrocehpalus

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HydrocephalusHydrocephalus

Obstruction to flow of CSFObstruction to flow of CSFOver production of CSFOver production of CSFInability of arachnoid Inability of arachnoid granulations to restore granulations to restore water of CSF back into water of CSF back into circulationcirculation

HydrocephalusHydrocephalusNoncommunicating: Can’t get out of ventriclesNoncommunicating: Can’t get out of ventriclesCommunicating: CSF can’t get to arachnoid granulationsCommunicating: CSF can’t get to arachnoid granulations

TraumaTrauma

Birth traumaBirth traumaHemorrhageHemorrhagePermanent lossPermanent loss

TraumaTrauma

Closed headClosed headCoupCoupContraContra--coupcoup

PenetratingPenetratingHemorrhageHemorrhageContusionContusionLacerationLaceration

ContusionsContusions

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Subdural HemorrhageSubdural HemorrhageRotational injury tears little veinsRotational injury tears little veinsSlow venous bleedingSlow venous bleeding

Epidural HemorrhageEpidural Hemorrhage

Trauma with skull fxTrauma with skull fxMiddle meningeal a.Middle meningeal a.Hemorrhage Hemorrhage compresses braincompresses brain

Subarachnoid Subarachnoid HemorrhageHemorrhage

Not as commonly due Not as commonly due to trauma, but maybe.to trauma, but maybe.Arterial bleedingArterial bleedingTypically from Circle of Typically from Circle of WillisWillisBlood in subarachnoid Blood in subarachnoid spacespace

Vascular DiseaseVascular Disease

HypoxicHypoxicTIATIAStrokeStroke

InfarctionInfarction

HemorrhagicHemorrhagicVascular blowoutVascular blowoutTraumaTrauma

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Ischemic InfarctsIschemic Infarcts Hypertensive Hypertensive HemorrhagesHemorrhages

Berry aneurysmBerry aneurysmSubarachnoidSubarachnoid

ParenchymalParenchymal

Berry AneurysmBerry Aneurysm Subarachnoid Subarachnoid HemorrhageHemorrhage

Lacunar InfarctsLacunar InfarctsHypertensive vascular diseaseHypertensive vascular disease‘Watershed’ infarcts‘Watershed’ infarcts

Chronic IschemiaChronic Ischemia

Chronic vascular Chronic vascular insufficiencyinsufficiencyAtherosclerosisAtherosclerosisMarked cerebral atrophyMarked cerebral atrophy

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InfectionsInfections

Brain properBrain properMinengesMinengesBugBug

BacteriaBacteriaVirusVirusSpirochtesSpirochtesParasitesParasitesPrionsPrions

Bacterial MeningitisBacterial Meningitis

ExudateExudate over cerebral over cerebral hemisphereshemispheresBacteria grow in CSFBacteria grow in CSFCSFCSF

Cell countCell countGlucoseGlucoseProteinProtein

Age of patientAge of patientComplicationsComplications

ScarringScarringEpilepsyEpilepsyAbscessAbscess

Bacterial MeningitisBacterial Meningitis

Cerebral AbscessCerebral Abscess

Septic Septic endocarditisendocarditisBlood borne pathogensBlood borne pathogensMust surgically drainMust surgically drain

Viral EncephalitisViral Encephalitis

Infection of brain Infection of brain substancesubstanceHerpes Herpes -->>Absent temporal Absent temporal lobeslobesSporadicSporadicImmunsuppressedImmunsuppressedHIVHIV

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HIV EncephalopathyHIV Encephalopathy

MeningitisMeningitisNeuronalNeuronalBoth cognitive motorBoth cognitive motorDiffuse cortical atrophyDiffuse cortical atrophyMicroglia at site of dead Microglia at site of dead neuronsneuronsGP120 protein is directly GP120 protein is directly toxictoxic

Tertiary SyphilisTertiary Syphilis

Years after initial infectionYears after initial infectionObliterativeObliterative end end arteritisarteritisMeningitisMeningitisBrain properBrain properTabesTabes dorsalisdorsalis

PrionPrion DiseaseDisease

No nucleic acidNo nucleic acidSporadic or geneticSporadic or geneticAccumulation of Accumulation of abnormally folded abnormally folded proteinproteinVariety of Variety of conformations of the conformations of the diseased proteindiseased proteinSpongioformSpongioformencephalopathyencephalopathyKuruKuru

PrionPrion DiseaseDisease

Degenerative DiseasesDegenerative Diseases

Not just aging changesNot just aging changesNeuronal DeathNeuronal DeathGray matterGray matter

White matter changes are secondaryWhite matter changes are secondarySelective or generalized lossSelective or generalized lossAtrophy (local or global)Atrophy (local or global)Histological featuresHistological features

NeurofibrillaryNeurofibrillary tanglestanglesIntracellular or Intracellular or intranuclearintranuclear inclusionsinclusions

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Alzheimer’s DiseaseAlzheimer’s Disease

True dementiaTrue dementiaMarked atrophyMarked atrophyProtein alterationsProtein alterations

TauTau proteinproteinAmyloidAmyloid related related proteinproteinSenile plaquesSenile plaquesAmyloidAmyloidangiopathyangiopathy

Alzheimer’s DiseaseAlzheimer’s Disease

Progressive lossProgressive lossMemoryMemoryCognitiveCognitive

55--15 years15 yearsEventually loss of Eventually loss of languagelanguageHigher functionsHigher functionsParkinson’s in a fewParkinson’s in a fewPneumonia is often cause Pneumonia is often cause of deathof death

Alzheimer’s DiseaseAlzheimer’s Disease Alzheimer’s DiseaseAlzheimer’s Disease

Senile plaquesSenile plaquesVascular Vascular amyloidamyloid changeschanges

Parkinson’s DiseaseParkinson’s DiseaseParkinsonism, collection of symptomsParkinsonism, collection of symptoms

Rigidity, stooped posture, gait disturbances, pill rolling, faceRigidity, stooped posture, gait disturbances, pill rolling, faceDrug inducedDrug induced

Parkinson’s DiseaseParkinson’s Disease

HuntigntonHuntignton DiseaseDisease

HereditaryHereditaryProgressiveProgressiveExtrapyramidalExtrapyramidal motormotorChoreaformChoreaform movementsmovementsHuntington geneHuntington gene

TrinucleotideTrinucleotide repeatsrepeatsCAGCAGNormal 6Normal 6--34 copies34 copiesHD has 50HD has 50--70 repeats70 repeats

Caudate nucleus Caudate nucleus atrophyatrophySuicide and infectionsSuicide and infections

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Amyotrophic Lateral Sclerosis (ALS)Amyotrophic Lateral Sclerosis (ALS)

Sporadic loss of Sporadic loss of motor neuronsmotor neuronsSpinalSpinalBulbarBulbarPoor swallowingPoor swallowingPneumoniaPneumonia

DemyelinatingDemyelinating DisordersDisorders

White matterWhite matterDisease of Disease of oligodendrocytesoligodendrocytesAutoimmune most timesAutoimmune most times

Multiple SclerosisMultiple Sclerosis

Lesions dispersed in Lesions dispersed in space and timespace and timeCome and goesCome and goesSymptomsSymptoms

Optic nerveOptic nerveUrinationUrinationHeat makes worseHeat makes worseWeaknessWeakness

Degeneration of white Degeneration of white mattermatterPlaquesPlaques

Multiple SclerosisMultiple Sclerosis

Areas of Areas of demylinizationdemylinizationPlaquesPlaques

Active repairActive repairQuiescentQuiescent

Multiple SclerosisMultiple Sclerosis

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Toxic and Vitamin DeficienciesToxic and Vitamin Deficiencies

Thiamine DeficiencyThiamine Deficiency

BeriberiBeriberiAlcohol abuseAlcohol abuseAbrupt psychotic changesAbrupt psychotic changesWernicke’sWernicke’s encephalopathyencephalopathy

Hemorrhages in Hemorrhages in mamillarymamillary bodiesbodiesConfusionConfusionParalysis of Paralysis of extraoccularextraoccular musclesmusclesAtaxiaAtaxia

Korsakoff’sKorsakoff’sInabilbityInabilbity to form new memoriesto form new memoriesConfabulationConfabulation

B12 DeficiencyB12 Deficiency

Inability to maintain myelinInability to maintain myelinPosterior column degenerationPosterior column degeneration

EthanolEthanol

Acutely, neural depressantAcutely, neural depressantInhibitions go firstInhibitions go firstLoss of depth perceptionLoss of depth perception

ChronicChronicDegeneration of granular cell layer of cerebellumDegeneration of granular cell layer of cerebellumLoss of Purkinje cellsLoss of Purkinje cellsBergman’s Bergman’s gliosisgliosis

Fetal alcohol Fetal alcohol syndromsyndromMicrocephalyMicrocephalyGrowth retardationGrowth retardationFacial abnormalitiesFacial abnormalitiesMental retardationMental retardation

Abnormal migration of neurons during developmentAbnormal migration of neurons during development

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CNS TumorsCNS Tumors

Primary vs. Primary vs. metastaticmetastaticBenign vs. malignantBenign vs. malignantFocal vs. diffuseFocal vs. diffuseAbove or below Above or below tentorumtentorumNot too common in adultsNot too common in adultsAbout 20% of childhood malignanciesAbout 20% of childhood malignanciesLocation is criticalLocation is criticalCell typeCell type

None are of neuronal originNone are of neuronal originAstocytomaAstocytoma, most, mostOligodendrocytomaOligodendrocytomaMicrogliomatosisMicrogliomatosisEpendymomaEpendymoma

AstrocytomaAstrocytoma

AstrocyticAstrocytic originoriginAbove Above tentorumtentorum most times most times in adultsin adults

Multiple gradesMultiple gradesCompresses surrounding Compresses surrounding tissuetissueHemorrhage and necrosisHemorrhage and necrosisWith higher grade With higher grade malignant tumors, malignant tumors,

Look for vascular growthLook for vascular growth

AstrocytomaAstrocytoma AstrocytomaAstrocytoma

EpendymomaEpendymoma MeduloblastomaMeduloblastoma

ChildrenChildrenMidline cerebellumMidline cerebellumSubarachnoidSubarachnoid spreadspread

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MeduloblastomaMeduloblastoma MeningiomaMeningioma

Arise from Arise from meningesmeningesBenign in a biological Benign in a biological sensesenseConsider where it isConsider where it isFibroblast lookingFibroblast lookingCells in whirls and Cells in whirls and clustersclustersPsammomaPsammoma bodiesbodies

MeningiomaMeningioma

PsammomaPsammoma bodiesbodiesLittle calcificationsLittle calcificationsMicroscopicMicroscopicWithin the tumorWithin the tumorCan spot on XCan spot on X--rayrayConcentric layers Concentric layers -->>

Peripheral NervesPeripheral Nerves

Axon vs. Axon vs. SchwannSchwann cellscellsMotorMotorSensorySensory

Inflammatory, autoimmuneInflammatory, autoimmuneToxicToxicTraumaTraumaVascular, especially diabetesVascular, especially diabetesTumorsTumors

GuillianGuillian--BarrBarréé SyndromeSyndrome

Autoimmune?Autoimmune?Follows Follows

InfectionInfectionviral viral MycoplasmaMycoplasma

Allergic reactionAllergic reaction

DemylinizationDemylinizationAscending paralysisAscending paralysisPhrenicPhrenic nerve involvement is life threateningnerve involvement is life threatening

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Peripheral Nerve Peripheral Nerve TumorsTumors

Actually nerve Actually nerve sheath tumorssheath tumors

SchwannSchwann cellscells

Cranial nerves tooCranial nerves tooV & VIIIV & VIII

NeurofibromatosisNeurofibromatosis

Two typesTwo typesNo capsuleNo capsuleType 1Type 1

GeneticGeneticAll over the bodyAll over the bodyGliomaGlioma of optic n. (rare)of optic n. (rare)MeningiomaMeningiomaCafCaféé--auau--laitlait spotsspotsPigmented nodules of irisPigmented nodules of iris

NeurofibromatosisNeurofibromatosis