Review Questions 3 Flashcards
What are the most common tumors that metastasize to the brain?
- Disseminated Melanoma (50% of metastasis)
- Breast and lung (35%)
- Kidney and colon (5%)
**Prostate, liver and sarcomas rarely spread
- A chronic demyelinating disease of the CNS in which there are numerous patches of demyelination throughout gray or white matter?
- Which disease?
- White matter
- Multiple Sclerosis (MS)
- Disease which affects both sensory and motor functions
- Characterized by exacerbations/remissions over period of several years
MS
- MS is commonly found in which climates? Which climate is it rare in?
- MS is acquired at which age? Rare in which ages?
- Common: temperate climates
- Rare: Tropics
- Acquired: age 30
- Rare before 14 yrs, rare after 60 yrs
Which sex is most affected by MS?
Women, twice as often!
Etiology of MS
Idiopathic. But, experimental/clinical studies point to:
- genetic
- immune
- infectious
Plaques are the hallmark of this diease
MS
- Describe plaques of MS.
- Where are they most commonly located?
- Variable size w/ smooth rounded contour
- Usually in white matter, but occasionally breech the gray-white junction
With MS, where do the plaques prefer to be?
Optic nerves and chiasm, uniformly localized to periventricular white matter
What are plaques in MS?
Areas of demylenation
Clinically, when does MS onset?
3rd or 4th decades
When a patient with MS has an “exacerbation,” what does this mean?
There is a formation of new plaques of demylenation
What are the initial sxs of MS?
- Sxs related to lesions of optic nerves, brainstem, or spinal cord.
- Blurred vision or loss of vision in one eye is common
With MS, if the initial lesion is in the brainstem, what are the 2 most troubling early sxs?
- Double vision
- Vertigo
W/ MS, plaques within the spinal cord show which sxs?
- Weakness of one or both legs
- Sensory sxs (numbness in LE)
Are sxs of MS reversible?
Yes, many sxs are “partially reversible” within a few months, but in most patients the course of the disease is chronic relapse/remitting
- MS patients range from minor disability to severe incapacity (paralysis, dysarthria (slurred/slow speech), severe visual defects, incontinence, dementia.
- Patients w/ MS usually die of which 2 things?
- Respiratory paralysis
- UTIs (as most are women)
*When they are in a terminal coma*
An Intracranial Schwannoma (acoustic neuroma) is restricted to which cranial nerve, located where?
8th CN in the cerebellar pontine angle (CPA)
Causes tinnitus, deafness, and if large enough can compress cranial nerves.
Intracranial Schwannoma (acoustic neuroma)
Are acoustic neuromas (Intracranial Schwannoma) malignant?
Rarely, although they can recur with incomplete excision
What is an example of pseudomembranous infammation?
C. difficile causing pseudomembranous colitis caused by a bacterial overgrowth secondary to intake of broad spectrum abx.
A complication of wound healing from lack of sufficient tensile strength resulting in separation of wound margins.
Dehiscence
- Deficient scar formation occurs in DM patients due to ischemia and metabolic disturbances. These patients have higher levels of experiencing wound dehiscence due to what?
- What substance is not produced as much in patients tx w/ corticosteroid hormones which lead to dehiscence?
- DM: Sluggish formation of granulation tissue
- Cortico: Collagen
Excess scar formation w/ defective remodeling of scar tissue/results in immature scar
- What is an example of this?
- What are they composed of?
- Keloid
- Type 3 Collagen
Etiology of keloids?
Genetic
Vascularized connective tissue that is rich in macrophages + (myofibroblasts, angioblasts, fibroblasts). What is this called?
Granulation tissue
Precursors of blood vessels that proliferate like sprouts from the several small blood vessels at the margins of the wound. (Development of new blood vessels)
Angioblasts/Angiogenesis
- Healing of sterile surgical wounds
- Incision site initially contains coagulated blood forming a scab
- PMNs invade scab (scavenge debris), then 2 - 4 days later replaced by macrophages
Healing by First Intention
- Composition of the wound matrix changes from Fibronectin and Collagen 3 –> Collagen 1
- Proliferation of epithelial cells from wound margins cover defect within 3 - 7 days
Healing by First Intention
Granulation tissue filling a skin defect of a wound healing by primary intention will transform into a scar by when?
3 - 6 weeks
Wound healing of large defects and all infected wounds
Secondary intention
- Granulation tissue exposed to external surface
- Myofibroblasts cannot accomplish wound contraction
Secondary intention
Type 3 collagen
Mature or Immature?
Immature
Type 1 Collagen
Mature or Immature
Mature, most common form of collagen in body
an antibody or other substance which binds to foreign microorganisms or cells making them more susceptible to phagocytosis.
Opsonin
2 examples of opsonins
- Immunoglobulins (Fc)
- Complement (C3)
•A special form of chronic inflammation that typically is not preceded by an acute, PMN-mediated inflammation.
Granulomatous Inflammation
What causes Granulomatous Inflammation?
- antigens that evoke a cell-mediated hypersensitivity reaction
- antigens that persist at the site of inflammation
Oral cavity to esophagus is made of which type of tissue?
Stratified squamous
Stomach to Anus, which type of tissue?
(pancreas, gallbladder, liver)
Glandular
When the heart is damaged, this is loss of myocardial cells. How does the heart repair itself? What cells is it made of?
- Fibrous scarring
- Non-dividing/Permanent cells (do not proliferate under any circumstances)
- Damage to heart is irreversible
Damage to brain results in loss of brain cells. How does the brain repair itself?
What cells?
- Gliosis/Astrogliosis
- Non-dividing/Permanent cells
- Irreversible damage
What are the 3 cell types that enter the cell cycle?
- Continuously dividing (labile) cells
- Quiescent (stable) cells
- Nondividing (permanent) cells
- Stem cells (RBC) , which type of cell?
- Bone marrow
- Intestine
Continuously dividing (labile cells)
Cells of parenchymal organs (solid) : liver and kidneys are made of which cell type?
Quiescent cells (stable cells)
Neurons and Myocardial cells are which cell type?
Nondividing (permanent) cells
- 20% of primary intracranial neoplasms
- Poorly demarcated, infiltrates cortex, indistinct margin
- Can be seen in pons and cerebellum of children
- Can be seen in cervical spinal cord in young adults
Grade 1 Astrocytoma
- Life expectancy is 5 years w/ therapy: surgery and radiation
- Transformation to higher degree anaplasia (GBM) occurs in 10% of cases which shortens life expectancy
Grade 1 Astrocytoma
- Greater cellularity
- Cellular pleomorphism
- Anaplasia
- Rapid growth of tumor
- Life expectancy of 3 years w/ therapy
Anaplastic Grade 2 Astrocytoma
- 40% of primary intracranial neoplasms
- Predominates in later decades of life
- Life expectancy of 18 months w/ therapy
- Infiltrates extensively into cortex, frequently crossing corpus callosum
Glioblastoma Multiforme (GBM)
- Extends bilaterally into white matter of both hemispheres
- Has both mottled red (recent hemorrhage) and yellow (remote hemorrhage)
- Looks like butterfly
GBM
How does HTN compromise the integrity of cerebral arterioles which leads to HTN associated aneurysms?
Through deposition of lipid and hyaline material in the walls (lipohyalinosis)
Charcot-Bouchard aneurysms are small fusiform dilatations in the trunk of a vessel as opposed to bifurcation. They are predisposed to rupture and cause which type of hemorrhage?
Hypertensive cerebral hemorrhage
What may cause death by transtentorial herniation?
Hypertensive Intracerebral hemorrhage
Etiology of strokes
Atherosclerosis predisposes pt to vascular thrombosis and embolic events
(ischemic strokes most common)
