Exam 2: [Pathology Of The CNS] Flashcards
Causes of Primary Diseases in the CNS & (%)
10% of Diseases
1) CVA
2) Epilepsy
3) Trauma
4) Tumors
5) Infections
6)Cerebral Edema
7) Hydrocephalus
Cause of Secondary Diseases in the CNA & (%)
90% of Diseases
1) Circulatory Failure
2) Cardiac Disease
3) Metobolic Causes
4) Chemical Causes
Manifestations of CNS Disease
1) Disturbances of Conciuosness
2) Increased Cranial Pressure
3) Focal Neurological Signs & Symptoms
4) Epilepsy
Causes of Increased Intracranial Pressure
1) Tumor
2) Infections
3) Hemorrhage or Hematoma
4) Infarction
5) Trauma
6) Cerebral Edema
7) Hydrocephalus
8) Pseudotumor Cerebri
Effects of Increased Intracranial Pressure
1) Headache
2) Vomiting
3) Papilledema - Optic Atrophy
4) Brain Herniations
Types of Brain Herniations
1) Mid-Line Shift
2) Tentorial Herniations
3) Tonsillar Herniations
4) Caudal Shift of Brain Stem
Types of Disturbances of Conciousness
1) Confusion (Disorientation)
2) Syncope
3) Lethargy
4) Stupor
5) Coma
Non-Communicating Hydrocephalus
Occurs when the flow of CSF is blocked along one or more of the narrow passages connecting the ventricles.
Communicating Hydrocephalus
CSF can still flow between the ventricles, which remain open
Causes of Hydrocephalus
Congenital
Acquired:
Trauma, Infection, Hemmorhage
Anencephaly
Serious birth defect in which a baby is born without parts of the brain and skull
Types of Spina Bifida
Occulta: Posterior Arch
Meningocele: CSF goes through Posterior Arch, Spinal Cord stays forward
Myelomeningocele: CSF & Spinal Cord go through the Posterior arch
Spina Bifida: Patient features
1) Acrania
2) Protruding Eyes
3) Long Arms
Syringomyelia (Syrinx)
Fluid-Filled Cyst forms in the Spinal Cord
Trisomy 21: Features
[Down Syndrome]
- Single Palmar Crease
- Intestinal Stenosis
- Hypotonia
- Umbilical Hernia
- Congenital HeartDefects
- Epicanthal Folds
Trisomy 18: Features
[Edwards Syndrome]
- Prominent back of head
- Low-set ears
- Cleft Palate/Small Mouth & Jaw
- Clenched Fist Hands
- Clubfeet w/ webbed or fused toes
Trisomy 13
[Patau Syndrome]
- Palm Crease
- Flat back of head
- Dental Abnormalities
- Congenital heart Disease
- Enlarged Colon
- Umbilical hernia
- Unilateral or Bilateral Absence of 1 Rib
Cerebral Palsy
- Cognitive Impairment
- Slurred Speech
- Lack of Muscle Control
- lack of Bowel Control
Neurofibromatosis
- Tumors form on Nerve Tissue
(Brain, Spinal Cord & Nerves) - Noncancerous
Neurofibromatosis Type 1
[Childhood - Chromosome 17]
- “Von Recklinghausen Disease”
- Multiple benign skin & peripheral nerve tumors
- Cafe-au-lait spots
Neurofibromatosis Type 2
[Early Adulthood - Chromosome 22]
- Central type, B/L Acoustic Neuromas (8th Nevre)
- Deafness
- 7th CN Compression
Trigeminal Neuralgia (Tic Douloureux)
- Light touch = Painful
- Trigger Zone on face or Intraoral
- 45+ years old
Associated Lesion with Arnold-Chiari
Kinking of Dorsal Aspect of lower Medulla/Upper Cervical Cord
Sturge-Weber Syndrome: What is it?
Cavernous Hemangioma, Port-Wine Stain
Calcifications along Deep Layer of Cortex
Sturge-Weber Syndrome: Clinical Features
1) Mental Retardation
2) Hemiparesis
3) Associated with Seisures
CerebroVascular Accidents Types
Hemorrhagic Stroke
Ischemic Stroke
Hemorrhagic Stroke: General Info
- Subarachnoid or Intracranial
- 10% of all strokes
- Most serious in Consequence
- Loss of Conciousness
- MCly Causes Death
Ischemic Stroke: General info
- 90% of all Strokes
- NO loss of Consciousness
- May occur slowly
- Global or Regional
- Regional Preceded by TIA’s
Ischemic Stroke: [Global Ischemia] Cause & What is at Risk?
Cause: Widespread Hypoxia or Hypotension
At More Risk:
- Neurons > Glial Cells
- Pyrimidal cells of Sommers (Hippocampus
- Purkinjie cells (Cerebellum)
- Water-Shed Infarction
- Laminar Necrosis
Water-Shed Infarction: Arteries Involved
Anterior & Middle Cerebral Arteries
Laminar Necrosis: Cortex Layers Involved
4th & 6th Cortical Layers
Embolic Stroke
[Regional]
- Thromboemboli, Gas Embolism, Fat Embolism etc
Thrombotic Stroke
[Regional]
- From Thrombi in the Cerebral Arteries themselves
Results of Ischemic Stroke
1) Loss of Neurons
2) Liquefactive Necrosis
3) Fluid-Filled Cyst in Brain
Congenital Berry Aneurysm
- (Saccular) forms on Circle of Willis
- Born w/ weakness in vessel @ bifurcation point
- Rupture suddenly to produce subarachnoid hemorrhage
(%) of Aneuryms at MC Arteries
35% Internal Carotid Complex
30% Anterior Communicating Artery
30% Trifurcation
5% Other Sites
Atherosclerotic Aneurysm
- Due to Weakening of vessel wall by atherosclerosis
- Larger Arteries (Circle of Willis or its branches)
- Larger Aneurysm may have symptoms (mass effect)
Charcot-Bouchard Aneurysm
- Microaneurysm that develops on Striate Arteries of a damaged artery wall
- Basal Ganglia or Internal/External Capsule
- Prior Hx of Chronic Hypertension
- Rupture -> Intracerebral Hemorrhage in brain tissue itself
What is a histological sign of previous hemorrhage?
Hemosiderin-Laden Macrophages
Arteriovenous Malformations: Etiology, Symptoms & Presentation
- Congenital/Asymptomatic
- Presentation: Spontaneous Hemorrhage
Arteriovennous Malformations: Effect after Rupture
Sudden Loss of Consciousness & Death in a young Individual in association with an episode of HBP
Types of Acquired CNS Diseases
1) Trauma
2) Circulatory
3) Infections
4) Demyelinating Disorders
5) Degenerative Diseases
6) Vitamin Deficiencies
7) Neoplasms
Coup vs. Countrecoup Contusion
Coup: contusions on the brain are directly below the point of trauma
Contrecoup: contusions on the brain are directly opposite the point of trauma.
Penetrating Injury: High velocity Bullet
- Entry wound & Exit wound
- Gases behind bullet expand immediately creating instantaneous increased pressure
Penetrating Injury: Low Velocity Bullet
- Entry Wound only (bullet lodged in brain)
- Hemorrhage along track of bullet & edema that cause increased pressure
- Slower
Spinal Cord Hyperextension
- Posterior Contusion
- Rupture of Anterior Spinal Ligament
Spinal Cord Hyperflexion
- Anterior Contusion
- Teardrop Fracture Anterior Lip of Vertebrae
Hemisection of the Cord-Brown-Sequard
- Ipsilateral Paralysis: Loss of fine touch, Vibration & Position Sense
- Contralateral: Loss of Pain & Temperature
Complete Transection
Pressure that develops following the injury because of Inflammation
QQ: Dementia can be temporary state of loss of entail and intellectual function brought on by drugs, acid-base imbalances, infectious disease, or conditions brought on by dehydration. (T/F)
False
QQ: The Etiology of Cerebral Palsy is:
Mechanical
QQ: Which of the following pathological findings is not associated with Arnold Chiari Malformation?
Enlarged Occipital Fossa
QQ:Congenital obstructive hydrocephalus is usually associated with a decreased absorption of CSF at the Arachnoid Granulations. (T/F)
False
QQ: Which of the following is not a neuroglial cell of the CNS?
Astrocytes, oligodendrocytes, Microglial Cell, Schwann cell
Schwann Cell
QQ: All of the following are classic features of an increase in intracranial pressure, EXCEPT: papilledema, the presence of calcium soft tissue deposits, headaches, vomiting
The presence of calcium soft tissue deposits
QQ: A concussion is defined as a temporary loss of conscious awareness following head trauma with visible organic brain injury as evidenced on an MRI or other radiographic studies. (T/F)
False
QQ: The mononuclear phagocytic cell of the CNS is called a:
Microglial Cell
QQ: Which one of the following changes within a cell is considered irreversible?
cloudy swelling, membrane bleb formation, pyknosis, hydropic change
Pyknosis
QQ: Most of the causes of disease that eventually affect the CNS actually begin in the brain. (T/F)
False
QQ: An atherosclerotic aneurysm is described as a ______ aneurysm.
Fusiform
QQ: The type of CVA that most often causes loss of consciousness is an ischemic CVA. (T/F)
False
QQ: Cerebral palsy in a premature infant most likely will eventually demonstrate:
Signs of Paraplegia
QQ: The flaccid paralysis often associated with the neurological deficits of polio are described as a/an:
Lower motor neuron lesion
QQ: A meningocele typically presents with the presence of a cyst protruding from the spine that contains CSF, spinal nerves, and a portion of the spinal cord. (T/F)
False
QQ: Ruptured bridging veins from the surface of the brain produce an epidural hematoma. (T/F)
False
(Sub dural hematoma)
QQ: Contrecoup injuries of the brain:
Are brain contusions that occur opposite the area of trauma to the head of a falling person.
QQ: A progressively enlarging cyst in the spinal cord that begins in the posterior columns and presents with loss of sensation across the shoulders in a cape-like distribution is referred to as a Syringomyelia.
(T/F)
True
All of the following are associated with Sturge-Weber syndrome, EXCEPT:
mental retardation, cavernous hemangioma, calcium deposition in the frontal lobes, Meningocele
Meningocele
QQ: The mechanism of hydrocephalus caused by Arnold-Chiari malformation is:
Obstruction due to tonsillar herniation
QQ: A Lewy body inclusion is associated with
Parkinson’s Disease
QQ: The type of CVA that most often causes loss of consciousness is an ischemic CVA. (T/F)
False
QQ: The most common cause of an acquired form of demyelination disease is multiple myeloma. (T/F)
False
QQ: The rupture of bridging veins connecting to the dural venous sinuses produce:
a Subdural hematoma
QQ: The most common site of primary tumors found in the CNS in children is:
Infratentorial
QQ: The most common type of neoplasms found in the Central Nervous System are what?
Metastatic Tumors
QQ: Perivascular cuffing is a classic feature seen in viral meningitis. (T/F)
False
QQ: Cowdry bodies are a type of inclusion body observed in neural tissue associated with:
Herpes Simplex Virus
QQ: Beta amyloid plaques are commonly associated with:
Alzheimer’s Disease
QQ: General Paresis Neurosyphillis affects:
Frontal lobes of the brain
Non-Mitotic Neuron
(Permanent)
No replacement if injured
Parenchymal Cells
Function cells of the Nervous System
Mature Neurons
Have No Neoplasms
Injury to neurons may produce:
1) Chromatolysis, Pyknosis
2) Wallerian Degeneration
3) Neuronophagy
4) Inclusion Bodies: (cytoplasmic vs. intranuclear)
Death of neurons produces:
Liquefactive Necrosis & in late stages formation of a Fluid-Filled Cyst
Astrocytes: General Info
- Most numerous in the NS
- Major supporting cell in brain
- Formation of blood-brain barrier
MC cell that causes of Primary Neoplasms of the CNS
When ASTROCYTES after injury create gliosis
(Equivalent of fibrous scar somewhere else)
Oligodendrocytes: Function & Damaged in What Diseases?
- Myelination in the CNS
- Damaged in Demyelinating diseases & Leukodystrophies
Ependymal Cells: Location & Function
- Single layer of cells lining ventricles of brain & central canal of spinal cord
- Produce plasma ultrafiltrate (CSF)
Ependymal Cells: Features
1) Cilia: keep CSF flowing
2) In some areas, Masses of capillaries derived from pia mater called Choroid Plexus
Microglial Cells: Origin & What are They?
- Origin: Blood Monocytes
- Phagocytes of the CNS that form microglial nodules or take up lipid to form foamy macrophages known as “Gitter cells”
What are Brain Herniations?
- Increase in ICP leading to herniation of intracranial CNS structures
- Eventually develop “false localizing signs”
Subfalcine (cingulate gyrus) Herniation:
“Mid-line shift”
- MC cerebral hernia
- Pushes Ipsilateral cingulate gyrus down under flax cerebri
Tentorial Herniation
Movement of brain tissue from one intracranial compartment to another (Like midbrain going down into brain stem area)
- Includes: Uncal, Central & Upward Herniations
Tonsillar Herniation
Cerebellar tonsils through foramen magnum
Caudal Shift of Brain Stem
“Transtentorial Herniation”
“Duret Hemorrhage”
- Brain stem falls through notch
Sturge-Weber Syndrome: Radiology, Associated with, & Clinical Features
- Calcify creating “Rail-Track” X-ray pattern
- Associated with Seizures
- Mental retardation & Hemipoesis
Epidural Hemotoma
- Between skull and outer most layer of meninges (dura mater) @ Sutures
- Involves artery, so can occur faster
Subdural hematoma
- Between Dura Mater & Arachnoid Layer
- Blood escapes forming a clot putting pressure on the brain
Neoplasms of the Nervous System: Clinical Features
1) Compression causing Cerebral edema
2) Inefficient Ducts
3) Neovascularization
4) Hydrocephalus from interference of CSF flow
Neoplasms of the Nervous System: Abnormal Stimulations
- Sensory or Motor (smells, sights, sounds)
- Jacksonian Epilepsy
Jacksonian Epilepsy
Peripheral twitching of (opposite side) extremities progressive to proximal muscle
MC Type of Glioma
Astrocytoma
Astrocytoma
- Low Grade (1), grow slowly but INFILTRATE, so hard to resect
- 5 year survival rate (50% if Dx early)
- Some response to radiation
Glioblastoma Multiforme
- Grade 4 Malignant Astrocytoma
- 33% of all Gliomas
- Forms butterfly tumor across mid-line -> Necrosis
- 20% 1 year survival
Juvenile Pilocytic Astrocytoma
- 25% of al brain CA’s
- Children under 10
- Operable, Good Prognosis
Oligodendroglioma
- Mid-life tumor
- 5-10 year post surgery survival
- 90% have calcification on radiograph (Speckled)
- Good prognosis
Ependymoma
- Brain: 60% in 4th Ventricle
- Children & Young Adults
- Mid-Life in Spinal Cord
Medulloblastoma
- Children & Young Adults
- Cerebellum
- Histological Rosette (characteristic sign)
- Metastasize via CSF to Spinal Cord
- 70% 5 Year Survival
Meningioma
- Tumor had Progesterone receptors
- Well circumcised mass attached to Dura
Meningioma: Microscopy
- Psammoma Bodies(concentric laminated Ca2+ rich)
- Whorled Pattern
- Meningothelial Cells
Lymphoma
- Primary to Brain (PBL)
- Transplant/AIDS patients (Immunocompromised)
- B-Lymph variety
Secondary Neoplasm
- Metastasis to Brain
- Meminges involved in Acute Leukemias
Secondary neoplasms: Metastasis order
Lung, Breast, Skin, Kidney, GI Tract
Craniopharyngioma: Embryonic
- Remnant of foregut 5% of brain cancers
- 2nd to 3rd decade of life
Craniopharyngioma: What does it Form in the Body?
- Encapsulated cyst with calcification around cholesterol crystals
- Superior to Sella Turcica
Craniopharyngioma: May Compress what Structures?
1) Hypothalamus (pituitary/growth retardation)
2) Optic Chiasm (visual defects)
3) 3rd Ventricle (hydrocephalus, headaches)
Guillain-Barre Syndrome: Etiology
- Follows Viral Infection, few after Immunization
- Autoimmune Destruction
Guillain-Barre Syndrome: Microscopy
- Poly Radiculopathy
- Demyelination of nerve roots/Cranial nerves
Guillain-Barre Syndrome:Clinical features
[Ascending paralysis]
- Tingling/weakness in extremities (feet)
- Migrate superior in (2-4 week period)
- Severe: Facial paralysis & Respiratory Failure
- Improvement takes several months
Guillain-Barre Syndrome: treatment
Supportive Physical therapy
Chiropractic Expedites Recovery
Myasthenia Gravis: Etiology
- Unknown, 15% have autoimmune diseases
- Lupus, RA
Myasthenia Gravis: Pathology
[Auto-Immune-Develops Antibody to ACh receptor]
Lymphocytic Infiltration
Thymus Hypertrophy (60-70% cases)
Myasthenia Gravis: Clinical Aspects
- 20 to 40 year olds
- Eyes: ptosis, diplopia
- weakening facial, pectoral girdle, neck flexor & respiratory muscles
Myasthenia Gravis: Course of Time
5-20 years (symptoms waxing & waning throughout)
Myasthenia Gravis: Treatment
Management: Anticholinesterase/Corticosteroid
- Prednisone
- Remove Thymus
- Limit activity in Summer Months
Trigeminal Neuralgia (Tic Douloureux): Treatment
- Anticonvulsant Drugs
- Local Cauterization of receptor Asensory
- Cryosurgery
Facial Paralysis (Bell’s Palsy): Cause, Population, Onset
Cause: Unknown (post-viral inflammatory??)
Population: Adult
Onset: Acute (side exposed to cold air
Facial Paralysis (Bell’s Palsy): Symptoms
1) Pain around Ear or in Mandible
2) Paralysis of unilateral facial muscles
3) Eye cannot close: biggest problem (no blink reflex)
Facial Paralysis (Bell’s Palsy): Treatment & Recovery
Tx: Corticosteroid, PT, Artificial tears, Eyepatch
Recovery: 80% full recovery in a few weeks
Diabetic Neuropathy: Pathogenic Hallmarks
1) Microangiopathy of Vasa Nervosum
2) Loss of Axons/Axonal Atrpohy
3) Demyelination
Toxic Neuropathy: Pathological Features
[By drug ingestion/chemical abuse]
- Axonal Degeneration/Transport
- Myelin Damage
- Peripheriral Neuron energy Metabolism
Schwannoma: Definition
Benign nerve sheath tumor arising from differentiated Schwann Cells
Neurofibroma: Components
1) Transformed Schwann cells
2) Non-neoplastic Fibrous Component
3) Fibroblasts
Toxic Neuropathy: Tissues Affected by Toxicity
1) Ranvier Node
2) Ion Channels
3) Small Fibers
Schwannoma: Pathological Features
- Encapsulated, well-circumcised
- Zonal pattern (Antoni A)
- Nuclear Palisading (verocay Bodies)
- Hypocellular component (Antoni B)
Schwannoma: Pathophysiology
Occur with: NF2, Carney Complex, Schwannomatosis
- Tumor Suppressor Gene “Schwannomin” dysfunc.
Schwannoma: Microscopy
Biphasic, Nuclear Palisading around Verocay Bodies
- Narrow cells interspersed with collagen fibers
- Dense Chromatin
- Nuclear Atypia, Cystic Degeneration & Hemorrhage
Neurofibroma: Essential Features
1) Elongated cells w/ dark wavy stained nuclei
2) Collagen Bundles & Mast Cells
3) Monomorphic Comma Shaped Nuclei
Neurofibroma: Etiology
- Caused by “Biallalic” Inactivation of Tumor Suppressor gene NF1
Neurofibroma: Sites
[Benign]
Localized: Superficially Evenly on Body Surface
Diffuse: Head & Neck Region
Plexiform: Major Nerve Trunk
