Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
525 Cards in this Set
- Front
- Back
RETROGRADE AXONAL TRANSPORT |
Herpes
Rabies Polio Tetanus toxin |
|
MCC of viral encephalitis?
|
Coxsackie virus
(late summer early autumn) |
|
MC CNS infection in HIV patients?
|
Cytomegalovirus
|
|
CMV meningitis: common findings- gross and microscopic? |
Gross: Periventricular calcifications
Micro: Basophilic intranuclear inclusions Rx: Gamcyclovir and foscarnet |
|
HSV-1 meningitis gross finding?
|
Hemorrhagic necrosis of temporal lobe
(Herpes= Hemorrhagic) |
|
Difference between bacterial and viral meningitides? (lab values)
|
GLUCOSE levels DECREASED in Bacterial meningitides
(<40mg/dl) |
|
Viral meningitides associated with decreased CSF glucose?
|
1. Mumps
2. Herpes 3. Choriomeningitis |
|
Arbovirus encephalitis: Name the virus. |
1. West nile virus
2. Reservoir- Wild birds(?) 3. Vector- mosquitoes |
|
Lymphochoriomeningitis: Vector? Route of transport?
|
1. Vector- Mouse
2. Route- Feco-oral contamination with mice feces Nuchal rigidity and mental status alteration |
|
Post polio syndrome?
|
1. Occurs 15-30 years after infection.
2. Presents with muscle pain, weakness and fatigue. |
|
Rabies:
Vector animal? Inclusion bodies? Describe |
1. Vector: Raccoon
2. Inclusion bodies- negri bodies Dark intracytoplasmic eosinophilic bodies. |
|
Rabies:
Viral receptor for entry? Phases of disease? |
1. Receptor-Acetylcholine receptor
2. Phases- Prodrome- Fever and paresthesias(at site) Hydrophobia- Pain due to throat muscle spasm while swallowing Encephalitis- Associated with negri bodies- seizures, coma, death |
|
Rabies: Rx?
|
1. Wash area with quart. NH4 compound.
2. Passive immunization at site 3. Active immunization with diploid human vaccine |
|
Rabies: Course of virus through body after infection?
|
1. Replication at site of bite
2. Retrograde axonal transport 3. CNS replication 4. Saliva |
|
Lacunar infarcts?
|
1. Microinfarcts <1cm
2. Hyaline arteriolosclerosis 3. Pure motor= Post limb of IC 4. Pure sensory= Thalamus |
|
Demyelinating diseases: Name them
(relevant to step1) |
1. MS
2. GBS 3. PML: Progressive multifocal leukoencepholopathy 4. CPM- Central Pontine Myelinolysis 5. Metachromatic leukodystrophy 6. Charcot Marie tooth disease 7. Postinfectious encephalitis |
|
Risk factors for meningitis?
|
1. Undernutrition
2. Otitis media 3. Pneumonia 4. Sickle cell disease 5. Immunodeficiency 6. Craniofacial abnormality |
|
Meningitis affects which meningeal layer?
|
PIA
|
|
Bacterial Meningitides are commonly gram (+ve or -ve)?
|
+ve
|
|
Imaging modality of choice in strokes?
|
CT with contrast
|
|
SAH headache patient description?
|
1. "Worst headache of life"
2. OCCIPITAL AREA 3. Nuchal rigidity |
|
SAH results from?(cause)
risk factor? |
1. Berry aneurysm rupture
2. AV malformations(less common) 3. risk factor: hypertension |
|
Complications of SAH?
|
1. Hydrocephalus
2. Hemorrhage(recurrence) 3. Permanent neuro deficit |
|
Hydrocephalus in SAH: cause?
|
Arachnoid granulations blocked
|
|
MC site for developing berry aneurysms?
why at that site? |
Junction of communicating branches with the main branches
1. ACA-ACA(40%) 2. MCA-PCA(20%) 3. PCA-PCA(8%) Internal elastic lamina and smooth muscle layer absent at these sites |
|
TE Stroke rx?
|
1. Thrombolytics within 3 hours
2. Chronic- Antiplatelets, warfarin |
|
Psammoma bodies:
Description? Disease associations? |
Description- Infarction and calcifications of papillary tips
Diseases- 1. Meningioma 2. Papillary ca of thyroid 3. Cystadenocarcinoma of ovaries 4. Renal CC 5. Mesotheliomas 6. Endometrial adenocarcinoma 7. Prolactinoma 8. Somatostatinoma(pancreas) |
|
Creutzfeldt jacob disease: Caused by?
|
Prion proteins- Proteins devoid of DNA and RNA
|
|
Creutzfeldt jacob disease: modalities of spread?
Gross appearance? |
1. Corneal transplant
2. Cortical electrodes 3. Infected beef tissue consumption Gross appearance: "bubble and holes" spongiform cortex |
|
Progressive multifocal Leukoencepholopathy: Etiologic agent?
|
Papovavirus (JC virus?)occurs in AIDS- <50cells/mm#3
|
|
Progressive multifocal Leukoencepholopathy: microscopic findings?
|
Intranuclear inclusions in oligodendrocytes and neurons
|
|
MC demyelinating disease?
|
MS
|
|
MCC of optic neuritis?
|
MS
|
|
MS: Microbial pathogens associated with it?
|
1. HHV6
2. EBV 3. Chl pneumonia |
|
MS: HLA association(autoimmune)?
|
HLA-DR2
|
|
MS: Autoimmune mechanism type?
|
Type IV
1. Helper T cells recognize the myelin basic protein as antigen 2. Cytokines from T cells(TNF-A) activate macrophages 3. Macrophages damage myelin sheath and oligodendrocytes |
|
MS: Gross findings?
Microscopic findings? |
Demyelinated plaques in white matter of brain
CD4 T cells and microglial cells with phagocytic lipids |
|
MS: Clinical findings?
|
1. Relapsing and remitting course
2. Optic neuritis- MCC of optic neuritis- blurry vision/loss of vision 3. Sensory dysfunction- Paresthesias, pain/temperature and vibration 4. Motor- UMN- dysfunction 5. Autonomic dysfunction- incontinence, sexual dysfunction, bowel problems 6. SIN- Scanning speech(drunk), Internuclear ophthalmoplegia(MLF demyelination), nystagmus 7. Lhermitte's syndrome- Neck flexion produces an electric shock like pain down the spine |
|
MS: CSF findings?
|
1. Leukocyte count- CD4+ cells
2. Gamma-globulins 3. MBP- indicates active demyelination/dz 4. High resolution electrophoresis- Oligoclonal bands on Gamma globulin region(indicates demyelination) |
|
MS: Dx? Rx?
|
1. Spinal tap- CSF examination
2. MRI with gadolinium- MOST SENSITIVE Rx- 1. Acute relapse- methylpredinisone- high dose steroids 2. Chronic- a. Interferon B b. Natalizumab c. Azathioprine d. Cyclophosphamide |
|
Central Pontine myelinolysis: Cause?
|
1. Rapid correction of hyponatremia(commonly in alcoholics)
2. Infections- Subacute sclerosing panencephalitis, PML |
|
Causative bacteriae for neonatal meningitis?
|
1. Group B strept(+ve
2. E.coli(-ve) 3. Listeria monocytogenes(+ve) |
|
Causative bacteria for adult meningitis?
|
1. S. Pneumoniae
2. N.meningitides 3. M.tb 4. T.pallidum(neurosyphilis) |
|
L.monocytogenes: source?
|
soft cheese, hot dogs
|
|
MC cause of neonatal meningitis?
|
Group B strept(S.agalactiae)
|
|
MC route of spread/source of neonatal meningitis?
|
Maternal vagina
|
|
Streptococcal meningitis: Rx?
|
1. Empiric: Ampicillin + Cefotaxim
2. Specific: Penicillin/Ampicllin |
|
2nd MC cause of neonatal meningitis?
|
E.coli
|
|
Ecoli meningitis: Rx?
|
1. Empiric: Ampicillin + Cefotaxime
2. Specific: Ceftazidime + Gentamicin |
|
MC meningitis in pediatric age group? rx?
|
Neisseria Meningitidis
Ceftriaxone |
|
M.tb meningitis: complications?
|
Vasculitis--> infarction
Scarring--> hydrocephalus |
|
MCC of adult meningitis? Rx?
|
S.pneumoniae(or N.meningitides?)
Penicillin G/ Ampicillin |
|
T.pallidum meningitis(neurosyphilis): types?
|
1. Meningovacuslar: vasculitis causing stroke.
2. General paresis: dementia 3. Tabes dorsalis: Post root ganglia, dorsal columns, argyll robertson pupils(prostitute's pupils)-involvement of pretectal area |
|
Rx neurosyphilis?
|
Penicillin G
|
|
Fungal causes of meningitis?
|
1. Cryptococcus
2. Mucor |
|
Fungal meningitis/encephalitis associated with immunocompromised patients?
|
Cryptococcal meningitis.
|
|
Stain used for Dx cryptococcal meningitis?
|
India ink: budding yeasts visible.
|
|
2nd MC cause of neonatal meningitis?
|
E.coli
|
|
Ecoli meningitis: Rx?
|
1. Empiric: Ampicillin + Cefotaxime
2. Specific: Ceftazidime + Gentamicin |
|
MC meningitis in pediatric age group? rx?
|
Neisseria Meningitidis
Ceftriaxone |
|
M.tb meningitis: complications?
|
Vasculitis--> infarction
Scarring--> hydrocephalus |
|
MCC of adult meningitis? Rx?
|
S.pneumoniae(or N.meningitides?)
Penicillin G/ Ampicillin |
|
T.pallidum meningitis(neurosyphilis): types?
|
1. Meningovacuslar: vasculitis causing stroke.
2. General paresis: dementia 3. Tabes dorsalis: Post root ganglia, dorsal columns, argyll robertson pupils(prostitute's pupils)-involvement of pretectal area |
|
Rx neurosyphilis?
|
Penicillin G
|
|
Fungal causes of meningitis?
|
1. Cryptococcus
2. Mucor |
|
Fungal meningitis/encephalitis associated with immunocompromised patients?
|
Cryptococcal meningitis.
|
|
Stain used for Dx cryptococcal meningitis?
|
India ink: budding yeasts visible.
|
|
Rx cryptococcal meningitis?
|
1. Flucanazole (Non AIDS pt)
2. Amphotericin B and flucytosine |
|
Meningitis that commonly occurs in diabetics? source? rx?
|
1. Mucor sp.
2. Source: frontal sinus 3. rx: Amphotericin B |
|
Meningoencephalitis associated with spread from water? Area of brain affected? rx?
|
1. Naegleria fowleri meningitis (meningoencephalitis)- protozoal
2. Frontal lobe 3. Amphotericin B |
|
Protozoal CNS infections: name the organisms?
|
1. Naegleria fowleri(meningoencephalitis)
2. Trypanosoma gambiense/rhodesiense(encephalitis) |
|
Sleeping sickness: causative agent? transmitting agent?
|
1. Trypanosoma gambiense/ rhodiense(encephalitis)
2. Tsetse fly (Glossina) |
|
Sleeping sickness: Course of organism through the body?
|
1. Blood/lymphatics
2. Posterior cervical LNs: Winterbottom sign 3. Encephalitis |
|
Trypanosomal encephalitis: clinical finding? (unique)
|
Somnolescence : hence the name- due to mediators released from organism
|
|
MCC death in sleeping sickness?
|
Starvation
|
|
Sleeping sickness: Dx? Rx?
|
Dx- 1. Characterisitic increase in IgG early in dz
2. Detect organism in blood/ CSF 3. Serology Rx- Early stage- Pentamidine Encephalitis stage- melarsoprol |
|
Most common CNS SOL in AIDS?
|
Toxoplasma gondii encephalitis
|
|
Cysticercosis: causative agent? transmitting agent?
|
Taenia solium
Pigs |
|
Cysticercosis: Course of organism through body? rx?
|
Cycle: Patient ingests food containing eggs --> develops into larval form --> invades brain --> calcified cysts --> seizures
Rx: albendazole + dexamethasone |
|
T.gondii encephalitis: part of brain affected? rx?
|
Parts: Basal ganglia
Rx: pyrimethamine+sulfadiazine+ dexamethasone |
|
Adrenoleukodystrophy: enzyme defect? effect? pattern of inheritance?
|
Defect involving b-oxidation of fatty acids.(?)
Effect: 1. Demyelination 2. Adrenal insufficiency. Inheritance: XR |
|
Metachromatic leukodystrophy: enzyme defect? fn of enzyme?
|
Enzyme: ASA
Fn: Hydroxylation of sulfate glycosphingolipids.: accumulation of sulfatides |
|
Metachromatic leukodystrophy: Stain? inheritance pattern?
|
Alcian blue and PAS
AR |
|
Krabbe's disease: enzyme defect? microscopic appearance?
|
Enzyme defect: Galactocerebroside b-galactocerbrosidase deficiency
Microscopic appearance: Multinucleated histocytic cells (globoid cells) |
|
Alzheimer's disease: types?
|
1. Sporadic: Late onset
2. Sporadic: Early onset 3. Familial: Early onset |
|
Trisomy associated with alzheimer's? pathology?
|
1. Trisomy 21: Down's
2. Chromosome 21 encodes for APP |
|
Alzheimer's disease: Pathology?
|
1. APP metabolized by sectretase alpha---> inactive fragments(cannot be converted to AB)
APP metabolized by secretes B or gamma --> fragments converted to AB--> increased phosphorylation by GSK(activated by inactivation of wingless integration pathway) phosphorylated AB protein--> neurotoxicity(induces neuronal apoptosis)--> alzheimer's 2. Tau protein phosphorylation by GSK produces neurofibrillary tangles(visualized by silver stain)- NF have altered structure--> cluster into fibres NF tangles--> neuronal death 3. Wingless integration pathway defect: required for inhibiting GSK--> increased GSK activity--> hyperphosphorylation 4. Pin 1 enzyme= prolyl isomerase removes phosphate molecules from NF. restoring its original structure--absent in some cases 5. Apolipoprotein gene E: allele epsilon 4 codes for a product that fails to eliminate AB from brain 6. Insulin degrading enzyme- degrades insulin and AB. in type II DM-- increased insulin levels decreases Insulin degrading enzyme-->more AB deposition GSK= glycogen synthase kinase |
|
Alzheimer's disease: Role of secretase alpha?
|
APP--> metabolized into inactive products not convertible to Amyloid. therefore protective
|
|
Alzheimer's disease: Role of secretase beta/gamma?
|
APP--> metabolized into fragments convertible into AB. therefore AD.
|
|
Alzheimer's disease: role of Glycogen Synthase Kinase?(GSK)
|
Hyperphosphorylation of:
1. Amyloid beta protein--> signals neuronal apoptosis 2. Tau proteins-->NF tangles(altered tau protein)-->neuronal death |
|
Normal function of tau protein? Role in Alzheimer's dz?
|
tau protein: scaffolding - maintains neuron structure
In Alzheimer's dz: increased phosphorylation of tau proteins-->NF tangles--> neuronal toxicity |
|
Alzheimer's disease: role of pin-1 enzyme?
|
Pin-1 enzyme- aka prolyl isomerase
strips excess phosphate from NF--restoring its original shape and structure |
|
AD: AB protein damages neurons - parts of the cortex involved?
|
1. Medial temporal lobe
2. Frontal cortex: entorhinal cortex 3. Hippocampus |
|
Wingless integration pathway: Function? role in alzheimer's disease?
|
Function: neuronal development during embryogenesis and normal functioning
Inhibits GSK |
|
Stains used to detect beta amyloid?
|
Congo red: apple green birefringence with polarization
|
|
Sporadic early onset AD: genetic defect?
|
apolipoprotein gene E. allelle epsilon 4
chromosome (19?) codes for product that cannot eliminate AB from brain |
|
Diabetes type associated with Alzheimer's disease?
|
Type II
Insulin increment reduces insulin degrading enzyme levels also needed for degradation of AB--> accumulates--> Alzheimers Dz |
|
Alzheimer's dz: Gross findings?
|
1. Cerebral atrophy- frontal, parietal, temporal
2. Ventricular dilation (hydrocephalus ex vacuo) **Occipital lobe- spared in AD** |
|
Alzheimer's dz: Microscopic findings?
|
1. NF tangles- silver stain
2. Senile plaques: Core AB(congo red) surrounded by Neuronal processes Microglial cells Astrocytes 3. Amyloid angiopathy- weakening of vessels--> hemorrhage. |
|
Alzheimer's diz: confirmatory dx?
|
Post-mortem examination. Senile plaques and NF tangles
|
|
Alzheimer's dz: early symptoms?
|
1. Short term memory loss- hippocampus
2. Loss of smell- entorhinal cortex dysfunction |
|
Common cause of death in Alzheimer's dz pts?
|
Infections: bronchopneumonia
(lack of hygiene) |
|
Alzheimer's dz: lobe spared?
|
Occipital lobe
|
|
Diseases associated with NF tangles? visualized by (stain)?
|
1. Alzheimer's dz
2. Huntington's dz 3. Niemann-Pick Visualized by silver stain |
|
Alzheimer's dz: Rx?
|
Cholinesterase inhibitors
Memantine- glutamate receptor blockers |
|
Parkinsonism: Causes?
|
1. Encephalitis
2. Ischemia 3. CO poisoning- necrosis of globus pallidus 4. Wilson's disease 5. MPTP- derived from meperidine 6. Antipsychotics- Phenothiazines |
|
Parkinsonism: Pathophysiology?
|
Depigmentation and degeneration of neurons: d/t loss of dopamine
|
|
Parkinsonism: Microscopic features?
|
Intracytoplasmic eosinophilic bodies: Lewy bodies.
|
|
Parkinsonims: What are Lewy bodies?
|
Intracytoplasmic eosniophilic bodies
Ubiquinated damaged neurofilaments. |
|
Intracytoplasmic eosinophilic bodies: Associated diseases?
|
1. Lewy bodies: Parkinson's dz
2. Negri bodies: Rabies |
|
Parkinsonism: Clinical features?
|
1. Bradykinesia
2. Rigidity: cogwheel 3. Tremors: resting, pill rolling- between thumb and index finger 4. Expressionless face: poker face 5. Shuffling gait 6. Blepharospasm 7. Seborrheic dermatitis. 8. Dementia |
|
Parkinsonism: treatment?
|
1. Levodopa
2. Carbidopa 3. MAO inhibitors 4. Bromocriptine 5. Pergolide |
|
Parkinsonism: Drugs that worsen disease?
|
1. Neuroleptics
2. Antiemetics 3. MAO inhibitors |
|
Huntington's dz: inheritance pattern?
|
AD
|
|
Huntington's dz: genetic defect? pathology?
|
CAG(codes for glutamine) repeats on Chromosome 4(Fab the hunter)
Atrophy of striatal neurons: 1. Caudate, 2. Putamen, 3. Globus pallidus |
|
Huntington's dz: clinical findings?
|
Chorea
Oculomotor defects Parkinsonism Depression (COPD) |
|
Huntington's dz: Dx?
|
Genetic testing
CT, MRI- atrophy of caudate and putamen |
|
Friedrich's ataxia: inheritance pattern? genetic defect/pathology?
|
AR
GAA repeat sequence- frataxin deficiency- impaired mitochondrial Fe homeostasis-->apoptosis (FFFF) (Friedrich's ataxia : Frataxin defect Fe homeostasis F*****) |
|
MCC genetic ataxic disorder?
|
Friedrich's ataxia
|
|
Friedrich's ataxia: sites affected?
|
1. Dorsal root ganglia
2. Dorsal columns 3. Spinocerebellar tracts 4. Corticospinal tracts 5. Large peripheral nerves |
|
Friedrich's ataxia: disease associations?
|
1. Hypertrophic cardiomyopathy
2. Type I DM |
|
Friedrich's ataxia: clinical findings?
|
1. Ataxia
2. Loss of vibration and proprioception 3. Loss of deep tendon reflexes-INITIALLY at ANKLES 4. Muscle weakness- L. Extr |
|
Friedrich's ataxia: Dx?
|
MRI- SC atrophy
Gene testing |
|
Lou Gehrig's dz: (ALS) Genetic defect?
|
Mutation on chromosome 21: Defective superoxide dismutase 1--> superoxide free radical injury
|
|
Lou Gehrig's dz: Clinical findings?
|
1. UMN signs: (Lower extrm)
2. LMN signs: (Upper extrm) 3. Atrophy of intrinsic muscles of hand Intact autonomic and sensory functions. |
|
Lou Gehrig's dz: Earliest clinical finding?
|
Atrophy of intrinsic muscles of hand.
|
|
Lou Gehrig's dz: Dx?
Rx? |
Electromyography and nerve conduction studies
Riluzole: glutamate antagonist |
|
Lou Gehrig's disease: MCC of death?
|
Respiratory muscle paralysis
|
|
Werdnig Hoffmann dz?
|
LMN dz in children.
|
|
Wilson's dz: inheritance pattern? Pathology?
|
Autosomal recessive
Defective incorporation of Cu into ceruloplasmin.--> increased free Cu in blood and cirrhosis |
|
Wilson'd dz: structures affected in CNS?
|
1. **Globus pallidus**
2. Putamen |
|
CNS signs in wilsons dz?
|
1. Parkinsonism
2. Chorea 3. Dementia |
|
Acute intermittent porphyria: enzyme defect?
Inheritance pattern? |
1. Uroporphobilinogen synthase/ porphobilinogen deaminase
Therefore increase in PBG and d-ALA--> neurotoxic 2. Inheritance: AD |
|
Urine color change in acute intermittent porphyria? Reason?
|
Light exposure produces port wine color. (window sill test)'
PBG--> porphobilin(colored product) on light exposure |
|
Acute intermittent porphyria: compound associated with disease?
|
Porphobilin
|
|
Acute intermittent porphyria: Drugs that worsen dz? how?
|
Barbiturates
Alcohol (Drugs that enhance P450) enzyme activity. ALA: Rate limiting enzyme of heme synthesis In AIP heme synthesis decreases--> increased activity of ALA synthase--> more porphobilin--> attack precipitated P450 inducing drugs also induce enhanced ALA synthase activity |
|
AIP: Clinical findings?
|
1. Painful abdomen- acute abdomen
2. Psychosis 3. Peripheral neuropathy 4. Dementia (PPPD) |
|
Severe combined degeneration of spinal cord: pathology?
|
Deficiency of B12--> methyl malonyl coA mutase cannot function--> incorporation of methylmalonic acid--> neuropathy
1. Degeneration of dorsal columns and corticospinal tracts. 2. Dementia 3. Peripheral neuropathy. |
|
CNS conditions associated with dementia?
|
1. Alzheimer's dz
2. Neurosyphilis 3. Parkinsonism 4. Wilson's dz 5. AIP 6. B12 deficiency |
|
Alcohol abuse: CNS findings?
|
1. Cortical atrophy
2. Cerebellar atrophy 3. Wernicke-Korsakoff syndrome(thiamine deficiency)- maxillary body hemorrhage a. Wernicke's: REVERSIBLE- Confusion, ataxia, nystagmus, ophthalmoplegia b. Korsakoff's: IRREVERSIBLE advanced stage- Amnesia, confabulation, hallucinations Rx- thiamine supplement |
|
MC primary CNS tumors in adults?
|
#1. Glioblastoma multiforme(high grade astrocytoma)
#2. Meningioma #3. Ependymoma |
|
MC primary CNS tumors in children?
|
#1. Cystic cerebellar astrocytoma
#2. Medullobastoma #3. Brain stem glioma |
|
Glioblastoma multiforme: GBM: Cell affected?
|
Astrocyte- high grade
|
|
Glioblastoma multiforme: MC site affected.
|
Corpus callossum
|
|
Glioblastoma multiforme: MC organ to get metastasized?
|
None(Rarely metastasizes)
|
|
Glioblastoma multiforme: Gross findings?
|
1. Hemorrhagic necrosis
2. Multiple areas of necrosis 3. Cystic degeneration MC site: corpus callossum |
|
Astrocytoma: Common sites of involvement- adults and children
|
Adults: Frontal lobe
Children: Cerebellum |
|
MC benign tumor in adults?
|
Meningioma
|
|
Meninioma: More common in : Men/women? why?
|
Women: tumors have estrogen receptor
|
|
Meningioma: Sites affected?
|
1. Parasagittal location
2. Olfactory groove 3. Lesser wing of sphenoid |
|
Meningioma: Disease associations.
|
1. Neurofibromatosis
2. Radiation exposure 3. New onset seizures |
|
CNS tumor associated with radiation exposure?
|
Meningioma
|
|
Meningioma: Gross features.
|
Firm mass- Indents surface of brain.
Infiltrates the overlying bone- increases bone density. |
|
Meningioma: Microscopic features?
|
Psammomma bodies in meningeal cells. (calcified swirling bodies)
|
|
Ependymoma: Malignant/ benign? MC sites?
|
Benign
Adults: Cauda equina Children: fourth ventricle |
|
Medulloblastoma: Site of origin? Metastasis to?
|
Cerebellum- External granular cell layer
Fourth ventricle |
|
Oligodendroglioma: Benign/malignant? Common site?
|
Benign tumor
Frontal lobe tumor- calcified. |
|
CNS lymphoma: Type? Association/s?
|
Type- Hodgin's lymphoma
Associated with- AIDS EBV mediated B cell lymphoma |
|
MC malignancy of brain?
|
Metastatic
|
|
Sites associated with CNS metastasis?
|
#1. Lungs
#2. Breast #3. Skin #4. Kidney #5. GIT |
|
Peripheral neuropathies.
|
1. Demyelination related- all
2. DM 3. Toxins- a. alcohol b. heavy metals c. diphtheria 4. Idiopathic Bell's palsy- CN VII a. Herpes Simplex- MC b. HIV c. Sarcoidosis d. Lyme dz e. Pregnancy 5. Drugs- a. Vincristine b. Hydralazine c. Phenytoin 6. Vitamins- a. Thiamine b. B12 c. Pyridoxine |
|
MCC of all peripheral neuropathies?
|
DM
|
|
Rx of peripheral neuropathies?
|
1. Antiseizures- Gabapentin, carbamazepine, phenytoin
2. Lidocaine 3. TCAs- a. Amitriptyline b. Nortriptyline |
|
MC hereditary peripheral neuropathy? Inheritance pattern?
|
Charcot Marie Tooth dz
Autosomal dominant |
|
Charcot Marie Tooth dz: MC nerve involved?
|
Peroneal nerve
Atrophy of lower legs--> inverted bottle appearance |
|
Inverted bottle appearance of legs seen in____?
|
Charcot Marie Tooth dz
(d/t atrophy of muscles of lower leg) |
|
MC acute peripheral neuropathy?
|
GBS
|
|
MCC of Acute flaccid paralysis?
|
GBS
|
|
GBS: Predominantly motor/sensory?
|
Motor
|
|
GBS: preceding infections?
|
1. Mycoplasma Pneumonia
2. Campylobacter Jejuni 3. HIV 4. EBV 5. CMV 6. Influenza 1. Mycoplasma Pneumonia 2. Campylobacter Jejuni 3. HIV 4. EBV 5. CMV 6. Influenza 1. Mycoplasma Pneumonia 2. Campylobacter Jejuni 3. HIV 4. EBV 5. CMV 6. Influenza 2 bacterial and 4 viral |
|
GBS: Course of muscle weakness?
|
**Rapidly progressive ascending motor weakness**
Starts in proximal muscles eventually distal muscles Areflexia "Glove stocking" paresthesias/anesthesia |
|
GBS: Common cause of death?
|
Respiratory failure due to failure of muscles of ventilation
|
|
GBS: Dx/ Laboratory findings?
|
1. Spinal tap- Increased CSF protein- Oligoclonal band on high resolution electrophoresis
2.Electromyography and nerve conduction studies |
|
GBS: Rx?
|
IVIG
Mechanical ventilation |
|
Diabetes Mellitus(DM): Peripheral neuropathy - reason?
|
Osmotic damage to Schwann cells
|
|
Bell's palsy: Clinical findings- LMN-UMN difference?
|
LMN- Ipsilateral upper and lower face involvement
UMN- C/l lower face involved and sparing of upper half of face |
|
CNS/PNS: Benign tumors?
|
Ependymoma
Meningioma Schwannoma |
|
Schwannoma/neurilemoma: Cranial Nerves generally involved?
|
1. CN V
2. CN VII |
|
Acoustic neuroma: CN involved- type of tumor? location?
|
1. Schwannoma
2. Cerebellopontine angle |
|
Acoustic neuroma: features?
|
1. Located at cerebellopontine angle
2. Encapsulated 3. Unilateral- except those associated with NF-2(B/l) 4. Alternating dark and light areas on microscope |
|
NF-2 associated acoustic neuroma- clinical features?
|
1. Tinnitus
2. Sensorineural deafness 3. Sensory changes in CN V distribution tumor compression on V |
|
Ulnar nerve injury:
Nerve roots of ulnar n? Commonly associated fx? Clinical finding? |
1. C8-T1
2. Fx of medial epicondyle of humerus 3. Claw hand- Interosseous muscle affected |
|
Radial nerve injury:
Nerve root? Associated fx? Clinical finding? |
1. C5-T1
2. Midshaft fx of humerus 3. Wrist drop |
|
Axillary nerve
Nerve root? Associated fx? Clinical finding? |
1. C5-C6
2. Fx of surgical neck of humerus/anterior dislocation 3. Loss of arm abduction(deltoid muscle paralysis) |
|
Median nerve:
Nerve root? associated fx? C6-T1 |
C6-T1
Associated conditions: 1. Rheumatoid arthritis 2. Pregnancy 3. Overuse of hands 4. Hypothyroidism 5. Amyloidosis 6. Supracondylar fx of humerus |
|
Median nerve compression/ carpal tunnel signs/symtoms?
|
1. Pain/paresthesias/ numbness over-
a. Thumb b. Index finger c. Middle finger d. Radial side of fourth finger 2. Thenar atrophy- ape hand, difficulty opposing thumb 3. Tinel's sign- Pain produced by tapping median nerve (tap with Tinel's) 4. Phalen's sign- Pain produced by flexion of wrist for 1 minute (Flex with Phanel's) Dx- nerve conduction studies, EMG |
|
Common peroneal nerve:
nerve roots? Associated fx? Clinical findings? |
L4-S2
common peripheral neuropathy lead poisoning Fx neck of fibula cast tightness 1. Loss of ankle reflex 2. loss of foot eversion- weakening of peroneus longus and brevis 3. loss of dorsiflexion- weakening of tibialis anterior- foot drop, high stepping/slapping gait 4. loss of toe extension- weakening of extensor digitorum longus and hallucis longus 5. In all EQUINOVARUS deformity |
|
Erb duchene palsy? Nerve roots involved?
|
C5, C6
"Waiter's tip deformity" |
|
Cerebral edema: types? causes?
|
1. Intracellular:
a. Dysfunctional Na/K pump(from global hypoxia) b. Hyponatremia(SIADH) 2. Extracellular: a. Inflammation: meningitis, encephalitis b. Metastasis c. trauma d. lead poisoning |
|
Head trauma: effect on respiration? how does this help?
|
Respiratory alKalosis--> vasoConstriction--> decreased vessel permeability
(In aciDosis--> vasoDilation. in acidosis, K channel activity increases--> K moves out--> hyper polarizes cell--> sm relaxation--> vasodilation) |
|
Signs of increased intracranial pressure?
|
1. Papilledema
2. Headache 3. Projectile vomiting 4. Sinus bradycardia 5. Hypertension 6. Herniation |
|
Pseudotumor cerebri? MC individuals affected/Risk factors?
|
Vit A excess/ All-trans retinoic acid-(used in rx of AML)
2. hypothyroidism 3. Cushing's disease 4. Isotretinoin 5. Tamoxifen |
|
Pseudotumor cerebri: pathogenesis? clinical findings?
|
Decreased CSF absorption in the arachnoid granulations
1. Findings in raised ICP 2. Rhythmic sounds in both ears 3. Diplopia 4. Blurry vision |
|
Pseudotumor cerebri: Dx? Rx?
|
Dx:
1. MRI: flattening of posterior globe 2. CSF pressure> 300mm H2O(normally 70-180 mm go H20) 3. Decreased CSF protein Rx: 1. Medical: a. Carbonic anhydrase inhibitor, b. Systemic corticosteroids 2. Surgical: a. Lumboperitoneal shunts, b. Optic nerve sheath fenestration |
|
Cerebral herniation: results as a complication of____?
|
Complication of raised ICP
|
|
Cerebral herniation: Name em. Parts of brain herniating associated and openings.
|
1. Subfalcine: Cingulate gyrus under falx cerebri
2. Uncal: Medial portion of temporal lobe through tentorium cerebelli 3. Tonsillar: Cerebellar tonsils herniate into foramen magnum |
|
Complications associated with:
Subfalcine Uncal Tonsillar herniation. |
1. Subfalcine: compression of ACA
2. Uncal: Compression of midbrain(III nerve nuclei--> Eyes deviated down and out+ dilated pupils) and PCA 3. Tonsillar: Cardiorespiratory arrest. |
|
Hydrocephalus: types? respective causes?
|
Types:
1. Communicating: a. Increased CSF production: choroid plexus papilloma b. Defect in reabsorption of CSF- Postmeningitic scarring 2. Non-communicating: 1. Stricture in aqueduct of sylvius--> Paralysis of upward gaze(Parinaud's syndrome) 2. Colloid cyst in the 3rd ventricle 3. Tumor in 4th ventricle- ependymoma, medulloblastoma 4. Scarring at the base of the brain: Tb meningitis |
|
Hydrocephalus: Clinical findings?
|
1. Signs of raised ICP
2. In children: enlarged head circumference in adults: no change in size |
|
Hydrocephalus ex-vacuo?
|
Dilated brain ventricles with reduced brain mass.
|
|
Normal pressure hydrocephalus: symptom complex? causes?
|
Dilated ventricles+ Wide based gait, Urinary incontinence, Dementia
(WWW- wet wobbly whacky) causes- 1. Idiopathic 2. Secondary: a. Prior SAH b. Prior Tumor c. Prior IC Sx |
|
Normal pressure hydrocephalus: pathogenesis?
|
Ventriculomegaly
Wide based gait and urinary incontinence: due to sacral motor fibre stretching Dementia: due to stretching of limbic fibres. |
|
Normal pressure hydrocephalus: Dx? rx?
|
MRI: ventriculomegaly and sulcal atrophy
Lumbar puncture: Large volume CSF removed--> improved symptoms Rx: Ventriculoperitoneal shunt Ventriculoatrial shunt |
|
Neural tube defects: Pathogenesis?
|
1. Failure of closure of lateral folds of neural plate
2. Rupture of closed NT. |
|
Serum marker associated with NTD?
|
Alpha feto protein in serum or amniotic fluid
|
|
NTDs: types?
|
1. Anencephaly
2. Spina bifida occulta 3. Meningocele 4. Meningomyelocele |
|
Anencephaly: Defect? Clinical finding?
|
Complete absence of brain
Polyhydramnios Raised AFP levels |
|
Spinca bifida occuta: Defect? clinical finding?
|
Failure of closure of post vertebral arch
Tuft of hair in skin over L5-S1 |
|
Meningocele: Defect? MC location?
|
Spina bifida with cystic mass containing meninges
Lumbosacral region |
|
Meningomyelocele: defect? MC location?
|
Spina bifida with cystic mass containing meninges and spinal cord
lumbosacral area |
|
Arnold Chiari malformation: Pathology? hydrocephalus- type?
|
Herniation of medulla and cerebellar vermis through foramen magnum
Non communicating hydocephalus |
|
Arnold Chiari malformation: Associations? Rx?
|
1. Syringomyelia
2. Meningomyelocele Rx: Decompression sx |
|
Dandy waker malformation: defect? hydrocephalus-type? rx?
|
1. Partial/complete absence of cerebellar vermis
2. Cystic dilation of 4th ventricle 3. Non communicating hydrocephalus rx- shunt |
|
Syringomyelia: Pathology/ Defect? associations?
|
Syrinx (fluid filled cavity) within the cervical spinal cord.-->cervical cord enlargement-->cavity expansion causes spinal tract degeneration.
Associated with Arnold- Chiary malformation type II Obstruction to the outflow to the CSF. |
|
Syringomyelia: clinical findings?
|
1. Lateral spinothalamic tract: Loss of pain and temperature B/l at the site of lesion--generally cervical(hands involved)
2. Corticospinal tract: Atrophy of intrinsic muscles of hands(c- ALS: no sensory loss) |
|
Syringomyelia: Dx? Rx?
|
Dx: MRI: dilated syrinx
rx: drainage of syrinx |
|
MC phakomatoses?
|
NF
|
|
Neurofibromatosis: types?
|
Type 1: Peripheral type
Type 2: Central type |
|
Neurofibromatosis type 1: genetic defect? Inheritance pattern?
|
Chromosome 17: neurofibromin- defective
AD |
|
Neurofibromatosis type 2: genetic defect? Inheritance pattern?
|
Chromosome 22: merlin - defective
AD |
|
NF-1: Important associations/Clinical findings?
|
1. Cafe au lait: 100% incidence in children <2yrs
2. Optic glioma: (astrocytoma) 3. Lisch nodules: Hamartomas of the iridae 4. Axillary and inguinal freckling 5. Scoliosis 6. Plexiform neurofibroma 7. Cutaneous/subcut. neurofibromas: DO NOT occur on soles and palms, increase in size with age 8. Pheochromocytoma 9. Wilm's tumor 10. CML 11. Neurodevelopmental problems |
|
NF-2: Important associations/Clinical findings?
|
1. B/l acoustic neuromas- benign, SN hearing loss
2. Meningiomas 3. Spinal schwannomas 4. Juvenile cataract |
|
NF syndromes: Dx? Rx?
|
Dx: genetic testing
Rx: Sx |
|
Tuberous sclerosis: Inheritance pattern? Clinical findings?
|
AD disorder
Clinical findings: Triad- 1. MR 2. Seizures 3. Ash leaf lesions/angiofibromas |
|
Skin lesions in tuberous sclerosis?
|
1. Angiofibromas: Adenoma sebaceum
2. Ash leaf lesion: hypo pigmented skin lesions aka shagreen's patch |
|
Tuberous sclerosis: tumors associated?
|
1. Angiomyolipomas: kidneys
2. Rhabdomyomas 3. Astrocyte proliferation in subependyma |
|
Tumor highly predictive of tuberous sclerosis?
|
Rhabdomyoma
|
|
Sturge Weber syndrome: Inheritance pattern?
|
1. Sporadic
2. Mosaicism |
|
Sturge Weber syndrome: associations?
|
Vascular malformation of face- area of distribution of trigeminal nerve.
Ipsilateral AV malformations in meninges. |
|
Cerebral contusions: common sites of involved?
|
Coup injury: cerebellum
counter coup injury: frontal and temporal lobes |
|
Acute epidural hematoma:
Commonly involved fx? vessel rupture associated? complication? Dx? rx? |
Fx : Temporoparietal bone fx-->
middle meningeal artery rupture(vessel lies between dura and inner table of bone) complication: raised ICP.--> herniation dx: CT - hematoma does not cross suture line rx: burr holes. |
|
Subdural hematoma
Vessel associated? Pathogenesis? Causes? Risk factors? Clinical findings? Dx? Rx? |
Venous bleed
Tearing of bridging veins b/w brain and dural sinuses (d/t loss of brain mass--> traction on the veins) Causes: 1. Blunt trauma 2. Anticoagulation 3. Hemophilia 4. Child abuse- shaken baby syndrome Risk factors: 1. Elderly 2. Alcoholics Clinical finidings: 1. Fluctuating levels of consciousness. 2. Herniation 3. Dementia: from chronic blood clot Dx: CT head Rx: Burr holes |
|
Global hypoxic injury: causes? complications?
|
Causes-
1. Cardiac arrest 2. Hypovolemic shock 3. Chronic CO poisoning ** Repeated episodes of hypoglycemia(effect similar to hypoxia)** Complications- 1. Cerebral atrophy- Apoptosis in areas 3,5,6 of cerebral cortex-->laminar necrosis 2. Watershed infarcts- Jn of ACA and MCA 3. CVA |
|
What are Red neurons?
|
Apoptotic neurons (from hypoxia)
|
|
Amaurosis fugax?
|
Temporary loss of vision due to embolization to bifurcation of the retinal arteries.
|
|
Strokes: peak age group? types?
|
types-
1. Ischemic- atherosclerotic/embolic 2. Hemorrhagic 3. SAH 4. Lacunar strokes |
|
MC type of stroke?
|
atherosclerotic
|
|
Sites of atherosclerotic strokes?
|
1. MCA
2. Internal carotid bifurcation |
|
Atherosclerotic strokes: Gross findings? microscopic findings?
|
1. Pale infarcts: periphery of cortex- wedge shaped
2. Swelling of brain- loss of demarcation of gray and white matter 3. Gliosis- reaction to injury- microglial cells 4. Cystic area- from liquefactive necrosis |
|
Arcus Senilis: identify. location? significance?
|
Gray opaque ring: Cholesterol deposits in corneal stroma
Cornea- more commonly corneal margin May indicate hypercholesterolemia if pt<50 yrs and smoker |
|
Common cause of conjunctivitis in neonates?
|
Causative organisms? Rx?
1. Ophthalmia neonatorum 2. i. N. gonorrhea ii.C.trachomatis rx- N.gonorrhea: ceftriaxone C.trachomatis: erythromycin |
|
MCC of bacterial conjunctivitis?
|
S. aureus
|
|
Bacterial conjunctivitis: causative bacteriae? Clinical findings? rx?
|
#1. S.aureus
#2. S.pneumonia #3. H.Influenza **pain but no blurry vision** rx- Gatifloxacin |
|
Viral conjunctivitis: causative viridae?
|
1. Adenovirus
2. HSV-1 |
|
HSV-1 conjunctivitis: complication?
|
Dendritic ulcers detected by fluorescein stain
|
|
Adenovirus clinical findings?
|
"Pink Eye" (MC viral cause of conjunctivitis?)
Periauricular lymphadenopathy |
|
Allergic conjunctivitis: rx?
|
rx: antihistaminics, olapatidine-mast cell stabilizer
|
|
Acanthamoeba infection: Site? patients affected? rx?
|
Keratoconjunctivitis- severe
Patients who do not cleanse their contact lenses. rx: propamidine+ polymyxin/neomycin/gramicidin |
|
Stye: MC organism? Rx?
|
S.aureus
rx: hot packs + dicloxacillin |
|
Chalazion: ? rx?
|
Granulomatous inflammation of the meibomian glands in eyelid
self resolving- 2months rx-intralesional corticosteroid injection/ sx removal |
|
Orbital cellulitis: Source? causative agents?
|
1. Secondary to sinusitis: ethmoiditis
2. i. S. pneumonia ii. H.influenza |
|
Orbital cellulitis: clinical findings? rx?
|
1. Fever,
2. Proptosis 3. Periorbital swelling 4. Ophthalmoplegia 5. <normal retinal examination> |
|
Orbital fx: characteristic finding? complications?
|
1. Raccoon eyes- edema and ehymosis of eyelids and periorbital region
2. Complications- i. Prolapse of orbital content maillary sinus- sunken eye ii. Infraorbital nerve compression |
|
Pterygium? cause? rx?
|
Raised triangular thickened conjunctiva on nasal side
Exposure to wind/sun/sand rx- sx removal |
|
Pinguelcula? location? rx?
|
Conjunctival degeneration.
Location: jn of conjunctiva and cornea- nasal side rx- none needed |
|
Optic neuritis: Causes? rx?
|
#1. Multiple sclerosis
#2. Methanol poisoning rx- corticosteroids |
|
Central retinal artery occlusion: causes?
|
1. Embolization from ipsilateral carotid and ophthalmic artery
2. Giant cell temporal arteritis |
|
Acanthamoeba infection: Site? patients affected? rx?
|
Keratoconjunctivitis- severe
Patients who do not cleanse their contact lenses. rx: propamidine+ polymyxin/neomycin/gramicidin |
|
Stye: MC organism? Rx?
|
S.aureus
rx: hot packs + dicloxacillin |
|
Chalazion: ? rx?
|
Granulomatous inflammation of the meibomian glands in eyelid
self resolving- 2months rx-intralesional corticosteroid injection/ sx removal |
|
Orbital cellulitis: Source? causative agents?
|
1. Secondary to sinusitis: ethmoiditis
2. i. S. pneumonia ii. H.influenza |
|
Orbital cellulitis: clinical findings? rx?
|
1. Fever,
2. Proptosis 3. Periorbital swelling 4. Ophthalmoplegia 5. <normal retinal examination> |
|
Orbital fx: characteristic finding? complications?
|
1. Raccoon eyes- edema and ehymosis of eyelids and periorbital region
2. Complications- i. Prolapse of orbital content maillary sinus- sunken eye ii. Infraorbital nerve compression |
|
Pterygium? cause? rx?
|
Raised triangular thickened conjunctiva on nasal side
Exposure to wind/sun/sand rx- sx removal |
|
Pinguelcula? location? rx?
|
Conjunctival degeneration.
Location: jn of conjunctiva and cornea- nasal side rx- none needed |
|
Optic neuritis: Causes? rx?
|
#1. Multiple sclerosis
#2. Methanol poisoning rx- corticosteroids |
|
Central retinal artery occlusion: causes?
|
1. Embolization from ipsilateral carotid and ophthalmic artery
2. Giant cell temporal arteritis |
|
Central retinal artery occlusion: clinical findings/ microscopic findings?
|
1. Sudden complete loss of vision in one eye
2. Pallor of optic disk 3. "Boxcar segmentation" of blood in retinal veins 4. Cherry red macula |
|
Cherry red macula- associated disorders?
|
1. Tay-Sach's dz
2. Niemann Pick 3. Central retinal artery occlusion |
|
Central retinal art occlusion: rx?
|
1. acetazolamide
2. carbogen- CO2 + O2 3. hyperbaric O2 therapy |
|
Central vein occlusion: causes? clinical findings/microscopic findings? rx?
|
1. painless unilateral loss of vision
2. swelling of optic disk 3. engorged retinal veins with hemorrhage- "blood and thunder appearance" 4. rx: laser photocoagulation |
|
Glaucoma- types- mechanism
|
open angle- reduced outflow rate through canal of schlemm
angle closure- narrowing of anterior chamber |
|
Open angle glauoma- clinical features? rx?
|
B/l aching eyes.
pathologic cupping of optic disk. night blindness. tunnel vision rx: 1st choice: b-blockers-timolol- decreases rate of flow 2nd: Prostaglandins/ alpha agonists/ pilocarpine/ carbonic anhydrase inhibitors. 3rd: laser trabeculoplasty |
|
Angle closure glaucoma: clinical features? rx?
|
1. Severe pain
2. Photophobia 3. Blurry vision 4. Pupil fixed and non reactive to light 5. Red eye rx: pilocarpine +systemic carbonic anhydrase inhibitors(lower pressure): for laser surgery |
|
Optic nerve atrophy: causes?
|
1. optic neuritis
2. glaucoma |
|
Uveitis: causes? clinical features? rx?
|
causes-
1. sarcoidosis 2. ulcerative colitis 3. ankylosing spondylitis clinical findings: 1. pain 2. blurry vision 3. circumcorneal vascular congestion 4. normal iop 5. iris and anterior lens capsule adhesions rx- corticosteroids atropine *uveal tract inflammation- ciliary boides, iris, choroid |
|
MCC of permanent vision loss in elderly? pathology?
|
Macular degeneration
Disruption of bruch's membrane in the retina. |
|
Macular degeneration: types? rx?
|
dry type: thinning of retina and formation of drusen: yellowish white plaque
wet type: retinal vessels hemorrhage-->retinal cell death --> blind spot/distorted central vision. rx- antiangiogenic- drug that block vascular growth factors. intraocular lens insertion |
|
MCC of blindness in AIDS patients? rx?
|
Cmv retinitis
CD4 count< 50cells/mm^3 Treatment: Oral, IV. Intraocular ganciclovir or foscarnet. |
|
Cataracts: causes? rx?
|
1. Age
2. DM 3. Infection- Rubella, CMV rx: cataract extraction |
|
Malignant tumors of the eye? rx
|
Retinoblastoma in children: white eye reflex/cat eye reflex
rx: enucleation |
|
Meniere's disease: pathology? clinical findings? rx?
|
1. Increased endolymph in the inner ear +
2. loss of cochlear hairs Clinical findings: 1. Dizziness 2. vertigo 3. tinnitus 4. sensorineural hearing loss rx: hydrochlorothiazide + triampterene |
|
MCC of sensorineural hearing loss in elderly? rx?
|
Presbycusis
degeneration of hair follicles rx: amplification devices, cochlear implants |
|
MCC of conduction deafness in elderly? rx?
|
Otosclerosis
fusion of middle ear ossicles other conduction defects: otitis media, impacted cerumen in middle ear. rx: antipyrine and benzocaine ear drops. |
|
External otitis. Etiologic agents? rx?
|
Inflammation of of outer ear canal.
"swimmer's ear" agents: 1. pseudomonas aeruginosa 2. Staphylococcus aureus 3. Aspergillus rx: polymyxin b+ neomycin+ hydrocortisone+ selenium sulphide |
|
MCC of malignant otitis externa? rx?
|
Pseudomonas aeruginosa
Imipenem- cilastin |
|
Spinal nucleus of V: location?
|
Dorsally and laterally - upper pons
(similar to location of dorsal columns in SC) |
|
Spinal tract of V: location and extent?
|
Spinal tract of V lies LATERAL to nucleus and
extension from- -entry point of V nerve -upto C2 |
|
Vascular syndromes associated with spinal nucleus and tract?
|
Lateral vascular syndrome: lateral pons and medulla
|
|
Solitary nucleus: location? CN associated? fn?
|
Location: upper medulla
CN: VII, IX, X function: receives visceral afferents: 1. Taste, (VII) 2. Cardiorespiratory, (IX, X) 3. GI sensations (X) |
|
Nucleus ambiguus:
Location? CN associations? function? |
1. Upper medulla: Dorsal to inferior olive
2. CN IX and X 3. LMN innervation of skeletal muscles of soft palate, larynx, pharynx, upper esophagus (swallowing and phonation) |
|
Dorsal nucleus of X: location? function?
|
Location: upper medulla and lateral to XII nucleus in floor of IV ventricle
Function: Parasympathetic(PREganglionic) nucleus of brain stem- Supplies smooth muscles and glands of thorax, foregut and midgut |
|
hypoglossal nucleus: location?
|
near midline- beneath central canal and 4th ventricle
|
|
Accessory nucleus: location? function?
|
location: cervical cord. c2
passes through the foramen magnum ---> cranial cavity ---> exits through jugular foramen. (intramedullary lesions have no effect on spinal accessory nerve) fn: supplies trapezius and sternomastoid. |
|
IX, X, XII nerve exits from brain stem: location?
|
IX, X: Exit between olive and fibers of inferior cerebellar peduncle
XII: Exit between the olive and medullary pyramid. |
|
Abducens nucleus: location? Structure relations?
|
Lower pons: midline floor of 4th ventricle-
#1. Lateral to MLF #2. Encircled posteriorly by facial nerve fibers( "internal genu" of facial nerve) #3. Closely associated with PPRF |
|
Nuclei in the floor of the 4th ventricle?
|
1. Abducens
2. Hypoglossal 3. Dorsal nucleus of X |
|
Superior olivary nucleus: Location? Function?
|
Ventral to VII nuclei--
Fn- B/l auditory impulses from both cochlear nuclei Sound localization |
|
Vestibular nuclei- Location
|
Posterior surface of pons- lower
Lateral to abducens nucleus Extends into the medulla |
|
Cochlear nuclei-location
|
PM jn lateral to the inferior cerebellar peduncles
|
|
Trigeminal nuclei- name em?
|
1. Sensory
2. Motor 3. Spinal Trigeminal 4. Mesencephalic |
|
Trigeminal nuclei- Motor nucleus: Location? function?
|
Pons: Medial to main sensory nucleus of trigeminal. At exit point of V
Supply muscles of mastication- 1. Medial and lateral pterygoid 2. Temporalis 3. Masseter |
|
Trigeminal: Sensory nucleus?
|
Pons: Lateral to motor nucleus. At exit point of V
fn- TACTILE and PRESSURE sense from V1, V2, V3 and DURA |
|
Spinal trigeminal nucleus: location? fn?
|
Location: Mid pons to C2
Functions- pain temperature by trigeminal nerve |
|
Mesencephalic nucleus : location? function?
|
At point of entry of 5th nerve.
Extends into MIDBRAIN fn- proprioceptive input from 1. muscles of mastication- sensory limb of jaw jerk 2. extraocular muscles 3. teeth |
|
V nerve nuclei associated with point of entry of V nerve?
|
1. Motor
2. Sensory 3. Mesencephalic |
|
Sensory distribution of CN V
|
ophthalmic: forhead, scalp, cornea, dorsum of nose
maxillary- maxillary skin mandible- mandibular skin, external auditory meatus, external tympanic membrane "onion skin configuration"- pain and temperature(spinal n.): 1: perioral 2: region of the eye 3: between ears and eyes 4: around the ears |
|
Motor fibers of V course through which division of V nerve?
|
Course of tactile fibers from face?
1st neuron: synapses in main sensory nucleus of V 2nd neuron: crosses midline in vicinity of its cell body--> synapses in thalamus(VPM nucleus) 3rd neuron: thalamus up to somatosensory cortex(join with pain fibers) |
|
Course of pain fibers from face?
|
1st neuron: enter spinal tract of V--> synapse in spinal nucleus of V
2nd neurons: cross midline in vicinity of CBs--> synapse in thalamus(VPM nucleus) 3rd neurons: thalamus unto somatosensory cortex (join with the tactile fibers) |
|
Complete lesion of trigeminal nerve at entry or exit points.
|
Complete ipsilateral anesthesia(sensory and spinal tract fibers)
Jaw weakness(motor fibers) |
|
Lateral/caudal pons lesion/lateral medullary lesion?
|
Ipsilateral loss of pain and temperature(spinal tract of V)
|
|
Corticobulbar/ corticonuclear fibers:
|
CN V- Mastication
CN VII- Facial expression CN X- Palate, larynx, pharynx CN XI- Sternomastoid, trapezius CN XII- Tongue except palatoglossus |
|
Difference between cranial and spinal LMNs?
|
1. Cranial- B/L corticobulbar(UMN) innervation--exception lower face from VII(U/L)
2. Spinal- U/L corticospinal(UMN) innervation |
|
Hair cells at base of cochlea- sensitive to?
|
High frequency
|
|
Hair cells at apex of cochlea- sensitive to?
|
Low frequency
|
|
Weber's test?
|
Tuning fork placed on vertex of skull.**
Conductive- Louder in affected ear Sensorineural- Louder in normal ear (**bone conduction interferes with air conduction so decreased perception in normal ear) |
|
Rinne test?
|
For conductive hearing loss
Place tuning fork on mastoid till no vibrations heard and then place next to the ear. Unilateral conductive hearing loss- No air conduction after bone conduction |
|
Conditions causing conuction deafness?
|
1. Otosclerosis
2. Otits media 3. Impacted cerumen |
|
Presbyucusis?
|
loss of hair cells in the base of the cochlea-
progressive loss of high frequency sounds |
|
ampular crest
utricle and saccule:fns? |
ampular crest- angular acceleration
utricle and saccule- linear acceleration(upright posture) |
|
Endolymph composition? Site of production?
|
High K+
Low Na+ Striae vascularis |
|
superior olive: function?
|
(pons)
sound localization. |
|
Lesion above cochlear nucleus?
|
slight hearing loss in both ears
poor localization-olive, lemniscus, thalamus etc |
|
lesion below cochlear nucleus?
|
Complete hearing loss in the affected ear
|
|
Ion channel myopathies?
Microscopy? |
Myotonia- sustained muscle contraction
Episodic hypotonic paralysis No muscle atrophy PAS +ve intracytoplasmic vacuoles |
|
Vestibular nuclei:
no? fn? Auditory pathway? |
. upright posture- source of UMN- vestibulospinal tract- a/gravity muscles-linear
acceleration hair cells 2. vestibulo-ocular reflex- fixation of the eye in response to head turning endolymph flow stimulate hair cells on side of turning---> stimulation of cochlear nerve(on side of turning)---> stimulates cochlear nucleus---> i. activates MLF to III nucleus on same side---> adduction(same side) ii. activates MLF to VI nucleus on opp side---> abduction(pop side) eyes move in opp direction |
|
Vestibular evoked nystagmus
|
Lesion on one sided--> stimulation of opp side.
therefore "Slow component"--> 1. Points in direction of lesion (adduction of opp eye abduction of same eye) 2. Due to the pathology "fast component"(corrective phase) --> 1. points to opp side of lesion 2. Due to cortical mediated correction |
|
Caloric test?
|
Brain stem fun in unconscious pts.
Cold water irrigation--> nystagmus to opp side Warm water irrigation--> nystagmus to same side COWS cool water= mimics lesion warm water= mimics stimulation |
|
vertigo?
|
perception of rotation
acute vertigo--> peripheral lesion chronic vertigo--> central lesion |
|
For conjugate movement to right
cortical gaze center in the frontal eye field: location? |
left cortex
|
|
Fibres for conjugate gaze: Pathway?
|
Descend down to brain stem and cross to the opposite side-->
Paramedian pontine reticular formation--> 1. Abducens on same side as PPRF 2. Oculomotor on opp side of PPRF(through the MLF) |
|
Paramedian pontine reitcular formation: location?
|
Pons: adjacent to VI nucleus.
|
|
MLF: Medial longitudanal fasciculus?
|
Heavily myelinated tracts:
axon fibers to and from III/IV/VI/VIII nerve |
|
Right abducens nerve lesion: Effect?
|
When patient asked to look right (from looking left position)
Left eye adduction possible Right eye abduction possible only upto the center: Reason: III nerve intact Superior oblique: weak abduction Inferior oblique: weak abduction |
|
Right abducens nucleus lesion: Effect?
|
1. Neither eye can look right.
Since abducens nucleus - very close to the PPRF 2. Compete right side facial paralysis(internal genu of facial nerve) ***PPRF, abducens nucleus and internal genu (VII)ALWAYS involved together*** |
|
Left MLF lesion : fn? Commonly involved disease?
|
Associated with IIIrd nerve function: adduction during conjugate gazing
MS Failure to adduct eye during gaze AKA "Internuclear ophthalmoplegia" |
|
Differentiate MLF lesion from pure oculomotor lesion?
|
In IIIrd nerve palsy:
1. Complete failure of adduction of the eye 2. No dilation of pupil and 3. Ptosis MLF lesion- convergence of eye possible. failure of adduction of eye only in conjugate gazing |
|
Left frontal eye field lesion?
|
1. Inability to move either eyes to right.
Facial muscle weakness-LOWER face- proximity of corticobulbar fibres to the frontal eye field. UPPER half spared. |
|
Pateint fails to move both eyes to right:
whats the site of the lesion? A. Right frontal eye field B. Left frontal eye field C. Right PPRF D. Left PPRF |
Either Left frontal eye fielder OR right PPRF
Left frontal eye field lesion: Lower 1/2 of face involved only(right-opp side of lesion) PPRF: entire face involved.(right-same side of the lesion) |
|
Brainstem- supplied by(blood supply)?
|
Vertebrobasilar system
|
|
Basilar artery formed by? location?
|
Joining of the vertebral arteries.
Pontomedullary junction |
|
Course of basilar artery?
|
Formed at PM jn--> runs along the medial surface of pons--> bifurcates into
post cerebral arteries at midbrain |
|
Medulla: blood supply?
|
Medial medulla-
Anterior spinal artery fed by vertebral artery Lateral medulla- PICA |
|
Pons- blood supply?
|
Medial: Basilar artery(paramedian branches)
Lateral-caudal(VII and VIII) - AICA. Lateral-rostral- superior cerebellar artery |
|
Cerebellar arteries:
Name em. Structures supplied? |
1. Superior- Rostral pons
2. Inferior- a. Anterior(AICA)- Caudal pons b. Posterior(PICA)- Lateral medulla |
|
Midbrain-blood supply?
|
Posterior cerebral artery- medial and lateral
|
|
Brain stem lesions- tracts affected with side.
|
Spinothalamic- C/L
Corticospinal-C/L Medial lemniscus-C/L Descending hypothalamic fibres- I/L(horner's) CN involved: I/L signs/symptoms |
|
Above brain stem level lesion: Effects?
|
IC/Thalamus/Cortex-
ALL- C/l signs and symptoms Lower 1/2 face weakness Spinothalamic fibers and descending hypothalamic fibers go together. lesion of one produces another in brain stem. |
|
medial lemniscus system- course across the brain stem?
|
medially in medulla
laterally in the mid brain |
|
Nuclei lined across-
medially to laterally along floor of 4th ventricle, Location of nuclei in upper medulla. |
hypoglossal-dorsal nucleus of X- solitary nucleus-vestibular nucleus
medial lemniscus- medially nucleus ambiguus- dorsal to the inferior olive CS tract dorsal to medial lemniscus CN IX and X- exit between inferior olive and pyramids CN XII- exits between the inferior olive and inferior cerebellar peduncle spinothalamic and hypothalamic tracts anterolaterally next to olive spinal trigeminal tract and nucleus adjacent to inferior cerebellar nucleus |
|
Medial medullary syndrome: cause? effect?
|
Cause- Anterior spinal artery occlusion
effect- pyramids- C/l spastic paralysis medial lemniscus- C/l loss of tactile, vibration, proprioception hypoglossal- I/l flaccid paralysis--> tongue deviation on protrusion towards the side of the lesion |
|
Lateral medullary syndromes(Wallenberg syndrome): cause? effect?
|
Cause: PICA
Effect: 1. Spinothalamic tract- C/l loss of pain and temperature 2. Descending hypothalamic fibers: I/L horner's syndrome 3. CN IX, X- Hoarseness, weak vocal cords, dysarthria, dysphagia 4. Spinal nucleus and tract- I/L loss of pain and temperature of face 5. Vestibular nucleus- N/V and vertigo 6. Cerebellar peduncle- I/L ataxia |
|
Medial caudal pontine syndrome: Cause? Effect?
|
Cause: Basilar artery(paramedian branches)
Effect: 1. Corticospinal- C/l spastic paralysis 2. Medial lemniscus- C/l loss of pressure/vibration 3. CN VI: strabismus- internal/medial |
|
Lateral pontine syndromes: Cause? Effect?
|
AICA
1. Spinothalamic tract: C/l pain and temperature- limbs/trunk 2. Descending hypothalamic fibres- I/L horner 3. Spinal nuclei and tract- I/L pain and temperature- face 4. VII- I/l facial muscle paralysis(LMN) 5. VIII- I/l hearing loss |
|
Pontocerebellar angle syndrome: cause? effect?
|
Cause: Acoustic neuroma
Effect: Affects CN VIII Compression of V, VII(LMN) ABSENCE OF LONG TRACT LESIONS |
|
Medial midbrain syndrome.
|
Corticospinal tract: C/l spastic lesion
Corticobulbar tract: C/l lower face weakness(UMN) III nerve lesion: I/L external strabismus, dilated pupils and ptosis |
|
Dorsal midbrain sydrome.
|
Pineal gland tumor: directly above superior colliculus and pretectal area
1. Disruption of vertical conjugate gaze 2. Diminished pupillary light reflex(pretectal area compression) 3. Elevated ICP- non communicating |
|
Reticular nuclei: name em.(Reticular formation)
|
1. Raphe nuclei
2. Locus ceruleus 3. Periaqueductal gray |
|
Raphe nucleus:
Location? Function? |
Location- Midline of brain stem- extends from medulla to midbrain
Function- serotonin(dorsal raphe nucleus) |
|
Locus ceruleus: function?
|
Synthesize norepeinephrine.
(associated with arousal/ sleep wake cycle) |
|
Periacqueductal gray:
location? function? |
Collection of nuclei surrounding cerebral aqueduct
Opioid receptors in periaqueductal gray- collaterals to spinothalamic tract-help suppress painful stimuli |
|
Cerebellum: parts? function?
|
Midline vermis: axial and proximal
Intermediate hemisphere: distal lateral hemisphere: motor planning flocculonodular lobe: balance and smooth conjugate gaze of eye muscles. |
|
Vermis/intermediate zone: function? input from?
|
Ongoing motor smooth execution of axial and proximal muscles.
input: proprioceptive inputs from muscle spindles and golgi tendon organs. |
|
Input to cerebellum from spinal cord thru ___cerebellar peduncle/s
|
Inferior and Middle
(IIM- Input inferior and middle) |
|
Output from cerebellum to spinal cord thru___cerebellar peduncle
|
Superior.
(OS) |
|
Lateral hemisphere:input from? function?
|
Input:
1. Cerebrum 2. Inferior olive: error detection function: motor planning |
|
Flocculonodular lobe: input from? function?
|
Input : Vestibular nucleus.(VIII)
function: balance and eye movements |
|
Cerebellar cortex layers?
|
Molecular layer:
Outer layer- cells: basket cells stellate cells parallel fibers(axons of granule cells) Purkinje cell layer: Middle- most important cell layer cells: purkinje cells Granular cell layer: innermost layer cells: Golgi cells Granule cells Glomerulus= Granule cell+ golgi cell axons+ glial capsule granule cells= the only excitatory cells in cerebellum |
|
The only excitatory cells in cerebellum ____
|
Granule cells
|
|
The only cells whose axons leave the cerebellum____
|
Purkinje cells
|
|
Purkinje cell: function and location?
|
Cerebellar middle layer- purkinje layer
function- all inputs to cerebellum influence firing of purkinje cells Only axons of purkinje cells leave the cerebellum.(longest axons in the CNS)----> influence deep Cerebellar nuclei(cerebellar medulla) |
|
All(except granule cells) outputs of cerebellum are: excitatory/inhibitory?
|
Inhibitory
|
|
All input to cerebellum are: excitatory/inhibitory?
|
Excitatory
|
|
Inputs to cerebellum:
fibers? associated tracts? Target and function? |
Mossy fibers:
Vestibulocerebellar--->Granule cells(excitatory- glutamate)---> purkinje cells Spinocerebellar--->Granule cells(excitatory- glutamate) fn: balance, smooth coordination Climbing fibers: Olivocerebellar--->Purkinje cells(excitatory) (inf. olives) fn: error detection |
|
Spinocerebellar and Vestibulocerebellar circuit system through cerebellar cortex?
|
Mossy fibers---> Granule cells---> Parallel fibers (axons of granule cells)--->Purkinje cells---> CB cells
|
|
Olivocerebellar circuit system through cerebellar cortex?
|
Climbing fibers---> Purkinje fibers--->CB cells
|
|
Cerebellum cell types? Target? Transmitter? function?
|
Cerebellum cell types? Target? Transmitter? function?
Purkinje cells-CB nuclei-GABA-Inhibitory Granule cells-Purkinje cells-glutamate-Excitatory Stellate cells-Purkinje cells- GABA- Inhibitory Basket cells- Purkinje cells-GABA-Inhibitory Golgi cells-Granule cells-GABA-Inhibitory |
|
Deep CB nuclei? associated cerebellar parts?
|
Fastigial: Vermis
Interposed: Globose+ Emboliform: Paravermis/intermediate Dentate: Lateral |
|
Basal ganglia: Fn?
|
1. Initiation
2. Suppression of unwaned movements 3. Gross motor |
|
Structural organization across horizontal section (CT head)
|
Caudate- striatum
Putamen-striatum separated by ant limb of internal capsule An External, internal globus pallidus(medial to putamen therefore lateral to the IC) Caudate- ant limb of IC-globus pallidus and putamen Substantia nigra subthalamic nucleus |
|
Basal ganglia circuit?
|
Cerebral cortex(motor)--> VL thalamus--> direct/indirect basal ganglia
|
|
DIRECT basal ganglia pathway?
Effect? |
DIRECT
Cortical excitation(glutamate) striatum(CAUDATE/ Putamen)(GABA) Globus pallidus-Internal(GABA) Thalamus(VA/VL) Motor cortex-->initiation of movement Direct: Drives movement |
|
INDIRECT basal ganglia pathway?
Effect? |
Cortical excitation(glutamate)
Striatum(GABA) Globus pallidus-External(GABA) Subthalamic nucleus(Glutamate) Globus pallidus- Internal(GABA) Thalamus(VA/VL) Motor cortex-->inhibition of movement Indirect: Inhibits movement |
|
Dopaine: site of formation? receptors? fn?
|
Dopamine-
dopaminergic neurons- substantia nigra Stimulate D1- Direct(GABA) D2-Supress indirect pathway Dopaminergic drive the direct pathway. Dopaminergics drive movement. |
|
Cholinergic transmission: Role in basal ganglia functioning?
|
Striatum
Stimulate-->indirect--> inhibition |
|
Diseases of basal ganglia?
|
Parkinson's: pathology
Direct basal ganglia pathway--loss of dopaminergic neurons-b/l So motor cortex active--loss of dopaminergic. therefore decreased direct pathway activity increased indirect pathway activity Tremor at rest Huntington's disease: Part of motor system affected? Associated with defective indirect pathway loss of GABA neurons in indirect pathway. Overactive motor cortex. |
|
Hemiballism: Part of motor system affected? symptoms?
|
Subthalamic nucleus- indirect structure
Wild flinging of movements U/L problem--> C/L effect associated with hypertension |
|
Tourette's dz: part of motor system affected?
|
Indirect basal ganglia phenomenon
Associated with OCD ADHD Rx- antipsychotics |
|
Wilson's dz: associated tremors?
|
Wing beating tremor- upper limb tremors associated with intention
|
|
Intentional tremors: lesion in ___(part of CNS)
|
Cerebellum
|
|
Eyeball layers? fn?
|
Outer-
Sclera- Attachment site for ocular movement muscles Corneal sensory fibers Autonomic sensory fibers Middle- Choroid- Blood supply to retina Inner-Retinal fibers |
|
Refractive areas of the eye?
|
Cornea- Non adjustable
Lens- Adjustable |
|
Posterior chamber- associated fn?
|
Ciliary bodies: epithelium produce aqueous humor
|
|
Drainage of aqeous
|
canals of schlemm at angle of anterior chamber
|
|
Parasympathetic and symathetic nerve supply to the eyes.
|
Parasympathetics-
III innervate ciliary muscle- sphincter- constrictor sympathetic- dilator -radial muscles cornea supplied by by V1 of trigeminal |
|
Light reflex pathway?
|
Retina-->CN II-->
b/l to midbrain nuclei(adjacent to sup.colliculi) pretectal nuclei--> b/l Edinger Westphal nuclei III nerve nucleus(parasympathetic-pregang)--> III nerve---> Ciliary ganglion(parasympathetic- postgang)--> pupillary sphincter ms-->miosis Afferent: CN II (Pretectal) Efferent: CN III (Edinger westphal and ciliary ganglion) |
|
Parasympathetic controlled muscles of the eye? Receptor? fn?
|
Pupillary sphincter
Ciliary muscles Receptors: Radial: alpha receptors Ciliary: beta receptors Fn: Radial: mydriasis Ciliary body epithelium: aqueous humor secretion |
|
Accommodation convergence reaction: components?
|
Accommodation
Convergence Miosis |
|
Accommodation convergence: Pathway involved?Parasympathetics-->
|
Parasympathetics-->
Ciliary contraction--> Suspensory ligament relaxation--> Increased convexity of lens--> Increased RI of the lens--> Near object focus |
|
Convergence: Involved muscles?
|
Skeletal muscle axons(III)-->
Medial recti |
|
Argyll Robertson pupil?
Associated dzs? Lesion site? |
Diminished light reflex
Accommodation reaction preserved Associated dzs - 1.Tabes dorsalis 2. Diabetes |
|
Marcus gunn pupil?
associated dz? associated test? |
Diminished pupillary light reflex.
Swinging light test: normal eye-- pupils constrict normally swing light immediately in affected eye--> dilation of both pupils associated dz: MS |
|
Horner's syndrome?
|
Lesion of oculosympathetic fibers:
T1- superior cervical ganglion syndrome-peripheral descending- central ptosis, miosis and hemianhidrosis Ipsilateral |
|
Adie pupil?
|
Poor light reflex
Good accommodation lesion of ciliary ganglia suppressed knee jerks/muscle streth reflex |
|
Transtentoral herniation: eye effect?
|
Uncal herniation--> compression of IIIrd nerve- "Down and out"
miosis- 1st sign.(since parasympathetic fibers are the outermost hence affected 1st) ptosis |
|
Retina: layers?
|
Ganglion layer
Inner nuclear layer Outer nuclear layer Outer segments associated with pigment epithelium |
|
Site of detachment of retina?
|
Outer segments are embedded in pigmented epithelium-->ultimately the retina degenerates due to lack of nutrients
|
|
Pigmented epithelia: fn?
|
pigmented epithelia--> transport glucose and vit a to outer segment of rods and cones
|
|
Rods- distribution? function?
|
Distributed across the retina except the fovea
Fn- Motion sensitive Night vision |
|
Optic pathway
|
3 Neuron pathway:
#1. Photoreceptors-->BIPOLAR CELLS(inner nuclear layer) #2. Ganglion cell layer(optic nerve)---> lateral geniculate body Pretectal area(light reflex) suprachiasmatic nucleus(hypothalamus) #3. |
|
2nd optic neurons cross midline: unique features?
|
1. Only 60% cross midlines @ optic chiasm(nasal nerve optic retina)
Temporal DO NOT. NASAL NERVES CARRY TEMPORAL information THEREFORE TEMPORAL HEMIFIELD INFO CROSS. 2. Cross above the level of their cell bodies |
|
Optic tract? Projecting nuclei?
|
Remixed optic nerves:
temporal retina+ nasal retina from opp eye Nuclei: Geniculate body Pretectal area Photoreceptors--> Bipolar cells--> Ganglion cells--> Optic nerves--> Optic chiasm--> Optic tracts--> Lateral geniculate body--> Optic radiations--> Prim visual cortex= Cuneal gyrus + Lingual gyrus |
|
Lesion ahead of optic chiasm:
Associated conditions? effect? |
associated conditions:
1. Optic neuritis(MS) 2. Central retinal artery occlusion 3. Internal carotid artery aneurysm effect: Complete monocular ipsilateral anopsia |
|
Lesion at optic chasm?
associated with? effect? |
1. May affect only temporal fibers
associated lesion- Medially expanding aneurysm of internal carotid artery. effect- IPSILATERAL MONOCULAR NASAL hemianopsia OR 2. AT chiasm Affect only nasal fibers Effect- BINOCULAR BITEMPORAL(heteronymous) Associated lesions- 1. adenoma- superior quadrantanopsia 2. craniopharyngioma- inferior quadrantanopsia |
|
Adenoma: associated visual field changes?
|
1. Bitemporal
2. Superior quadrant 3. Quadrantanopsia (aDenoma comes from Down) |
|
Craniopharyngioma: associated visual field changes?
|
1. Bitemporal
2. Inferior 3. Quadrantanopsia (Craniopharyngioma comes from the Ceiling) |
|
Lesions Past the chiasm:
Standard features- monocular/binocular? homonymous/heteronymous? |
features:
BINOCULAR HOMONYOUS |
|
MCA occlusion: visual structures affected?
|
Optic tracts
Optic radiations |
|
PCA occlusion: visual structures affected?
|
Primary visual cortex
|
|
Optic tract lesions: features?
|
C/L Homonymous hemianopsia
|
|
Lateral geniculate body lesion: features?
|
C/L Homonymous hemianopsia
|
|
Optic radiations' lesions: features?
|
#1. Meyer's loops: C/L homonymous sup quad hemianopsia
#2. Non Meyer's loops: C/L homonymous inf quad hemianopsia |
|
Meyer's loop?
associated lesions? Associated cerebral lobe? Target? |
Meyer's loops fibers - lower retinal fibers traversing laterally
(as meyer's loop)- carry superior visual info Associated lobe: Temporal lobe Associated lesion: 1. MCA infarct 2. Temporal lobe tumor Target: Lingual gyrus |
|
Lingual gyrus:
Location? Function? |
Location: Occipital lobe: prim visual cortex
Function: SUPERIOR VISUAL FIELD info processing |
|
Cuneus gyrus:
Location? Function? |
Location: Occipital lobe: prim visual cortex
Function: INFERIOR VISUAL FIELD info processing |
|
Non meyer's loop lesion:
effect? target? |
effect: C/L Homonymous inf quadrantanopsia
target: Cuneus gyrus |
|
Complete lesions of optic tract and optic radiations have the same effect: ?
differentiating factor? |
C/L homonymous hemianopsia:
Optic tract lesion will have slightly diminished pupillary light reflex Optic radiation lesion: no effect on pupillary light reflex. |
|
Primary visual cortex:
effect? cause? |
effect:
C/L Homonymous hemianopsia Macular sparing |
|
Macular sparing in primary visual cortex lesion: cause?
|
Cause of prim visual cortex lesion: PCA infarct
Macular vision area in cortex is supplied by collaterals from MCA (in addition to PCA) cause: PCA infarct |
|
Diencephalon: components?
|
Thalamus
Hypothalamus Epithalamus: pineal gland Subthalamus |
|
Mammillary bodies: fn?
|
Associated with memory consolidation
sites of degeneration from korsakoff psychosis |
|
Thalamic nuclei: Name em.
|
VPL
VPM VA VL MGB LGB Ant MD |
|
VPL: Input? Output?
|
Input: Sensory from body and limbs(Limbs=vpL)
Spinothalamic and Medial lemniscus Output: Somatosensory cortex vPm or vPl= Pain(sensory) |
|
VPM: Input? Output?
|
Input: Sensory relay from face(Makeup=vpM) and taste
Output: Somatosensory cortex vPm or vPl= Pain(sensory) |
|
VA: Input? Output?
|
Input: Motor info from BG(Globus pallidus, substantia nigra)
Output: Primary motor cortex |
|
VL: Input? Output
|
Input: Motor info from BG(GP), cerebellum(Dentate nucleus)
Output: Primary motor cortex: brodmann area 4 |
|
LGB:Input? Output?
|
Input: Visual info from optic tracts
Output: Visual cortex (L= Light) |
|
MGB: Input? Output?
|
Input: Auditory info from inferior colliculus
Output: Auditory cortex (M= Music) |
|
AN: Input? Output?
|
Input: Mammillary nucleus.(short memory processing into long term): "Mammillothalamic tracts"
Output: Cingulate gyrus(part of PAPEZ circuit) |
|
Papez circuit?
|
Mammillar bodies--> Mammillothalamic tract-->Anterior nuclear group thalamus--> Ant limb of internal capsule--> Cingulate gyrus--> Hippocampus-->fornix-->Mammillary bodies
|
|
MD: fn? stimulation associated with?
|
Input: amygdala, prefrontal cortex and temporal cortex
Output: Prefrontal cortex and cingulate gyrus Medial-dorsal nucleus. Involved in memory- damaged in Wernicke- Korsakoff syndrome Stimulation produces savage behavior |
|
Pulvinar: fn?
|
Integrate somatic visual and auditory input
|
|
Midline/intralaminar:Input? Output? fn?
|
Input:
Reticular formation Spinothalamic tract Output: Cingular gyrus fn Associated painful stimulus should be avoided in the future |
|
Limbic system: fn?
|
5 Fs:
Feeding Feeling Fleeing Fighting Fornicating |
|
Ventral nuclear group:
lesion associated with isolated lacunar stroke? |
Thalamic pain syndrome:
1. loss of position and vibration sense 2. Increased C/l pain-burning aching resistant to analgesic medications |
|
Hypothalamus:
location? |
1. Collection of nuclei in the wall of the 3rd ventricle
2. Above the optic chasm 3. Above the pituitary |
|
The only grossly visible part of the hypothalamus?
|
1. Mammillary bodies.
2. Posterior lobe of the hypothalamus |
|
Gross structures closely associated with location of hypothalamus?
|
1. Optic chiasm
2. Posterior pituitary 3. Mammillary bodies. |
|
Preoptic area:
Derived from ___? function? Effect of pre-optic lesions? |
Telencephalon
Fn: sex hormone RELEASE FACTOR production(estrogen/androgen) Effect: Before puberty: arrest of sexual development After puberty: Impotence and Amenorrhea |
|
Anterior region:
Location? Nuclei? fn? effect of lesion? |
Location-
Directly above the optic chiasm Nuclei: 1. Paraventricular 2. Supraoptic 3. Suprachiasmatic Function: Paraventricular and supraoptic 1. ADH 2. Oxytocin production and release into post pituitary(neurohypophysis) lesion--> diabetes insipidus polyuria polydipsia |
|
Suprachiasmatic: fn?
|
1. Circadian rhythm---> influences pineal gland
(Visual input from retina) supraChiasmatic= Circadian) |
|
Post pituitary contain____
|
Axons of paraventricular and supraoptic nuclei
|
|
Anterior pituitary derived from? cell types in pituitary?
|
From Rathke's pouch
Dorsal outgrowth of oral ectoderm. cell types- Acidophils Basophils |
|
Arcuate nuclei:
location? fn? |
Location:
hypothalamus- directly above the infundibulum fn: control release of anterior pituitary hormones. thru releasing and inhibitory factors--->hypophyseal-portal veins-->secondary capillary plexus in ant pituitary |
|
Ventromedial nucleus: VM nucleus;
location? Fn? |
Location: tuberal region of hypothalamus
fn: Satiety center: lesions--> obesity (VM= Vomit..you are full so you vomit.) |
|
Feeding center: location?
|
Lateral hypothalamus
lesions--> aphagia |
|
Posterior region:
nuclei/structures? respective fns? |
Mammillary bodies- part of limbic system: memory consolidation
Anterior hypothalamic zone: Senses body-temp elevation-->mediates heat dissipation response lesion-->hyperthermia Posterior hypothalamic zone Senses body-temp drop-->mediates heat conserving response. lesion-->poikilothermy |
|
Hyperthermia: associated hypothalamic lesion?
|
Posterior hypothalamic zone
|
|
Diencephalic structures associated with thiamin deficiency?
|
1. DM nucleus of thalamus
2. Mammillary bodies |
|
Epithalamus? location? fn?
|
Pineal gland : melatonin release(increased during darkness-->sleep)-
plays a role in - growth/development circadian rhythm habenular nucleus(fn:?) location: above posterior commissure |
|
pinealocytes: fn?
|
synthesis :
melatonin serotonin cholecystokinin melatonin production control through light across the retinal-suprachiasmatic-pineal pathway light inhibits-->melatonin darkness stimulate-->melatonin |
|
Pineal tumor-effect?
|
Parinuad syndrome:
Compression of superior colliculus- vertical conjugate gaze impaired midbrain- pupillary light reflex(pretectal area) |
|
Subthalamus: fn? lesion effect?
|
Movement inhibition(indirect basal ganglia pathway)
lesion: hemiballismus--- C/l flinging movements of extremities |
|
Primary motor cortex: location? Area no __?
|
Precentral gyrus
Area 4 |
|
Primary somatosensory cortex: location?
|
Postcentral gyrus
(poStCentral: SomatoSensory) |
|
Homunulus orientation across the cortical surface?
|
Laterally head (near lateral sulcus) --->medially legs/feet
|
|
Primary visual cortex: location? divisions?
|
Location: Medial surface of occipital lobe
division: (by calcarine sulcus) 1. Cuneus gyrus: Superiorly situated: Non meyer's loop info: Inferior visual field info 2. Lingual gyrus: Inferiorly situated- meyer's loops: Superior visual field info |
|
Area of brain associated with watershed infarct?
Cause? Effect? |
Area: Jn of ACA and MCA
Cause: Hypotension Effect: 1. Weakness of trunk musculature. 2. B/L loss of pain and temperature in trunk "Person in a barrel syndrome" |
|
Cortical cell layers?
|
1. Molecular layer
2. External granular layer(well developed in sensory cortices) 3. External pyramidal layer(well developed in motor cortices) 4. Internal granular layer(well developed in sensory cortices) 5. Internal pyramidal layer(well developed in motor cortices) 6. Multiform layer Layer 2, 4 well developed in sensory cortices: site of synapsis of thalamic relay nuclei Layer 3, 5 well developed in motor cortices UMN cell bodies--->from corticospinal/bulbar= aka Betz cells |
|
Structures supplied by posterior circulation--->
|
1. Brain stem
2. Cerebellum 3. Medial cerebral hemisphere 4. Inferior cerebral hemisphere |
|
MCA- cortical structures supplied?
|
Lateral aspect- upper half of body and face
|
|
ACA- cortical structures supplied
|
Medial aspect- lower half of body
|
|
Internal carotid aneurysms
Site? Effects? |
Site:
Before it branches off into MCA and PCA Effects: 1. Medially expanding: Compress temporal fibers of Optic nerve- Nasal hemianopsia 2. Laterally expanding: Cavernous sinus Compression of Abducens nerve- Internal strabismus |
|
Margins of cortex supplied by?
|
either-
ACA PCA NOT MCA |
|
Dominant hemisphere- left/right? blood supply?
|
Left hemisphere-
since it contains the language centers: Broca's area Wernicke's area (both on lateral surface) Blood supply- Left MCA |
|
Corpus callosum : blood supply?
|
MCA except Splenium- PCA
|
|
Cerebral artery most commonly associated with emboli?
|
MCA
|
|
Lacunar infarcts: cause? site? effect?
|
hypertension
penetrating branches of ACA/MCA- basal ganglia/diencephalon/IC |
|
Berry aneurysm: associated dzs?
|
1. Marfan's dz
2. ED type IV 3. ADPKD 4. Htn 5. Smoking |
|
Brodman areas?
|
Primary motor area: 4
Primary somatosensory area: 3,1,2 Primary visual cortex: 17 Oral comprehension: 22 (Wernicke's) Written comprehension: 39 (Angular) Auditory complex: 41 and 42 Visual field/voluntary c/l horizontal gaze: 8 Motor speech area: 44, 45 |
|
Premotor areas: fn? brodman no? input from? lesion effect?
|
Motor planning
area 6 input: basal ganglia, cerebellum lesion effect: Apraxia No weakness |
|
Somatosensory association area: location? fn? lesion effect?
|
Location:
Parietal lobe: lateral aspect Posterior to area 3,1,2. fn: Integration of sensory systems Lesion effect: Astereognosia No loss of touch /pressure sense |
|
Astereognosia and apraxia more common in _____(lt/rt) hemisphere damage?
|
Lt hemisphere damage
|
|
Frontal eye field: location: brodman no?
|
Frontal lobe: lateral aspect
Anterior to area 6 Brodman no :Area 8 |
|
Primary auditory complex: location? B no? lesion effect?
|
location: Superior bank of temporal lobe under lateral sulcus
B no: 41 and 42 Lesion effect: 1. B/L slight diminution of sound 2. Poor sound localization |
|
Visual cortex: location? brodman no?
|
Location: Medial aspect of occipital lobe
Brodman no: 17 |
|
Language centers? location? blood supply?
|
Broca's:
44 and 45 (motor speech areas) Location: Lateral aspect of frontal lobe Anterior to premotor cortex Wernicke's: 22(oral comprehension) loaction left temporal lobe- lateral Posterior to prim auditory complex Angular gyrus: 39(written comprehension) location: lateral aspect of parietal lobe-adjacent to visual association cortex |
|
Aphasia: name em
Common features? |
1. Broca's
2. Wernicke's 3. Gerstmann's 4. Conduction Agraphia |
|
Broca's aphasia: site? symptoms?
|
Reduced use of words- use of monosyllable words
aware and frustrated lesion may extend into adjacent primary motor areas: c/l spastic limb weakness |
|
Wernicke's aphasia site?symptoms?
|
fluent aphasia.
no comprehension verbal output- n misuse words- "ford salad" paraphasic speech unaware and not concerned by deficit area 22 |
|
Gerstmann's syndrome: site? symptoms?
|
Lesion in area 39: angular gyrus
Symptoms 1. Agraphia- cannot write 2. Alexia- cannot understand written material 3. Acalculia 4. Finger agnosia 5. Right-left disorientation 6. Unaware of defect Spoken language understood |
|
Conduction aphasia: site? defect?
|
Defect in fiber bundles that connect language centers
"Arcuate fasciculus" 1. Paraphrasing 2. Word finding pauses 3. Cannot repeat words/execute command-disconnect 4. Pt aware of deficit-- Frustrated |
|
Arcuate fasciculus? fn?
|
Fibers connecting language centers in frontal/temporal/parietal lobes
Comprehension-response. |
|
Non dominant lesion (Right parietal lobe lesion)dominant lobe?
test? |
Lesion: U/L neglect on C/L half of the body: left sided
No visual defect but fail to recognize No somatosensory defect Test: bisect line or write numbers on a clock face--cram now in right side |
|
Visual agnosia: lobe involved?
|
Temporal lobe- inability to recognize visual patterns
|
|
Prosopagnosia? lesion location?
|
Inability to recognize faces
lesion sites: 1. Area 20 and 21 of temporal lobe 2. adjacent occipital lobe typically temporal lobe infarct typical symptom: when person speaks, pt recognizes the individual. |
|
Disconnect syndrome: site? fn?
|
Transcortical apraxia
Alexia without agraphia |
|
Transcortical apraxia? lesion site?
|
Motor deficit of left arm on verbal command
Vascular occlusion of corpus callossum branches of ACA. (4/5ths of corpus callosum) verbal interpretation intact but information transmission across the corpus callossum from dominant hemisphere to right hemisphere fails to travel. No motor weakness. Right arm movement executed successfully on command. (no disconnect problem between wernicke's area and prim motor cortex on left. |
|
Alexia without agraphia. Cause? lesion site?
|
Cause: Occlusion of the left PCA
Left PCA supplies: 1. L.Visual cortex: right Lesion site: Splenium of corpus callosum Can write but cannot comprehend written material. |
|
Internal capsule blood supply?
associated tracts? |
Anterior limb-
medial striate branches thalmocortical rostral part of frontal lobes. Genu- lenticulostriate branches of MCA corticobulbar fibers Posterior limb: Lenticulostriate branches of MCA Corticospinal(entire homunculus) Somatosensory: Thalamocortical projections effect: C/L spastic paralysis C/L anesthesia |
|
Thalamic nuclei associated with thalamocortical projections?
|
VPL
VPM |
|
Structures supplied by Anterior spinal artery? deficit stroke?
|
Ant 2/3rd of spinal cord:
All affected except dorsal columns compare with ALS(limited to motor problems) |
|
PICA: structure supplied? Deficit after stroke?
|
Dorsolateral medulla - wallenberg syndromes
|
|
Vertebrobasilar system:?
|
Pontine arteries
AICA Superior cerebellar Labyrinthine |
|
Basilar artery: structures supplied? Lesion effect?
|
Medial aspect of pons
Medial pontine syndrome(CST+ CN VI) |
|
AICA: Structures supplied? Lesion effect?
|
Inferior cerebellum cerbellar nuclei
Lateral pontine syndrome:(STT, DHF, CN VII, CN VIII) |
|
Structures supplied by Anterior spinal artery? deficit stroke?
|
Ant 2/3rd of spinal cord:
All affected except dorsal columns compare with ALS(limited to motor problems) |
|
PICA: structure supplied? Deficit after stroke?
|
Dorsolateral medulla - wallenberg syndromes
|
|
Vertebrobasilar system:?
|
Pontine arteries
AICA Superior cerebellar Labyrinthine |
|
Basilar artery: structures supplied? Lesion effect?
|
Medial aspect of pons
Medial pontine syndrome(CST+ CN VI) |
|
AICA: Structures supplied? Lesion effect?
|
Inferior cerebellum cerbellar nuclei
Lateral pontine syndrome:(STT, DHF, CN VII, CN VIII) |
|
Superior cerebellar art: structures supplied? lesion effect?
|
Cerebellum and sup peduncle
Rostral and lateral pons= (STT DHF, V) |
|
Labyrinthine artery:structures supplied? lesion effect?
|
Inner ear
Sensorineural hearing loss |
|
PCA:structures supplied? lesion effect?
|
Midbrain
thalamus occipital lobe C/L hemianopsia with macular sparing Alexia without agraphia.(splenium of corpus callosum) |
|
Internal carotid branches? lesion effect of each branch?
|
Ophthalmic artery
Post comm artery Ant comm artery Middle Cerebral artery Posterior cerebral artery Lesions of respective branches of int carotid. Ophthal artery- retina- blindness(monocular) Post communicating artery= 2nd most common aneurysm Ant cerebral artery= C/l spastic paralysis of LL Ant communicating artery: MC site for developing aneurysm- B/l temporal inf homonyous quadrant anopsia. Middle cerebral artery: upper half of motor homunculus. 1. C/l anesthesia; 2. Gaze palsy= Unable to gaze away from lesion site 3. Aphasia(l) 4. Dysprosodias® 5. Gerstmann synd(L) 6. Hemineglect® |
|
Frontal lobe: functions?
|
1. Primary motor cortex/premotor cortex: C/l spastic paresis
2. Frontal eye fields: Eyes deviate to ipsilateral side 3. Broca speech: Expressive, non fluent aphasia(l), motor dysprosodia(monotone- no emotions attached) (r) 4. Prefrontal cortex: |
|
Prefrontal cortex: lesion?
|
1. Poor judgement
2. Difficulty concentrating 3. Apathy 4. Inappropriate behavior |
|
Parietal lobe: fns? lesions
|
1. Primary somatosensory cortex: C/l hemihypesthesia
2. Superior parietal lobule: C/l astereognosis/apraxia 3. Inferior parietal lobule- area 39(gerstmann syndrome: alexia/dyscalculia/dysgraphia/finger agnosia/CL hemianopia unilateral neglect(r) |
|
Temporal lobe: fns/lesions?
|
1. Primray auditory cortex: B/L diminished hearing
2. Wernicke's: Fleutn aphasia(l), sensory dysprosodia®: emotional content of speech not understood 3. Hippocampus: B/l lesions--> consolidation of short term--> long term memory 4. Amygdala: Kluver Bucy syndrome 5. Olfactory bulb, tract: Anopsia 6. Meyer loop: "Pie in the sky" |
|
Occipital lobe : fns/lesions?
|
Visual: C/l hemianopsia with macular sparing
|
|
Limbic system: fn?
|
Memory consolidation
Emotional response center Visceral fns- mainly smell Sex drive Behavior |
|
Unique feature: Olfactory system
|
I. Reaches-
1. temporal lobe 2. amygdala without thalamic relay II: Primary olfactory neurons are replaced continuously: 30-120 days. III. Do NOT form any sensory ganglia |
|
Fx of cribriform plate associated with? (lesions)?
|
1. Anosmia
2. CSF rhinorrhea |
|
Fns:
Hippocampus Amygdala fornix? |
hipp: memory consolidation
amyg: emotional content to memory Fornix: Connects hippocampus to the mammillary bodies loops over diencephalon |
|
Kluver bucy syndrome: cause?
|
1. hypotension
2. b/l lesion in amygdala and hippocampus 3. placidity 4. Visual agnosia 5. Hyper metamorphosis 6. Increased oral exploration 7. Hyper/hyposexual 8. Anterograde amnesia |