Chapter 32 WS Flashcards
What part of the brain do most CNS tumors occur.
cerebrum
What is the most common classification of brain tumor.
glioma
What are the functions of the cerebrum.
- Interpretation of sensory impulses and voluntary muscular activities;
- it is the center for memory, learning, reasoning, judgment, intelligence, and emotions
what type of primary cancer is most commonly responsible for metastatic brain cancer
lung cancer
Which hemisphere of the brain do most metastatic brain cancers occur.
cerebral hemispheres
List some late effects of radiation therapy to the brains of children.
- Decrease in IQ scores,
- impaired mental functions such as processing speed, attention, and working memory.
- Higher incidences of emotional distress such as anxiety and depression, which can diminish quality of life.
List three structures that are filled with CSF (cerebral spinal fluid).
ventricles, cancals, and subarachnoid space
what secretes CSF
Ependymal cells secrete about .5 L of CSF each day into the ventricles. The ependymal cells line the choroid plexuses.
What is the tentorium.
A fold of dura mater (the outer covering of the brain) that separates the cerebral and cerebellar hemispheres.
What structures are located in the supratentorial region..
- The cerebral hemispheres,
- the sella, pineal,
- upper brainstem regions
What structures are located in the infratentorial region.
- Brainstem,
- pons,
- medulla, and
- cerebellum
Where does the blood supply for the brain come from.
Internal carotid arteries and vertebral arteries via the circle of Willis.
primary source of enegery for brain cells
glucose
where does the spinal cord end
L1-L2
what does CSF look like
clear colorless fluid that resemebles water
list some lipid soluble substances
- alcohol
- nicotine
- heroin
list some water soluble substances
- glucose
- some amino acids
- sodium
what substances can cross the BBB
Lipid soluble.
Water-soluble substances can as well if they have a carrier molecule to cross the barrier via active transport
what is CSF composed of
- Proteins,
- glucose,
- urea (a compound formed in the liver and excreted by the kidney),
- salts.
signs and symptoms of intracranial pressure
- Headaches,
- vomiting,
- lethargy,
- seizures, and
- neurologic symptoms.
what is papilledema
edema of the optic disc
results from increased intracranial pressure
List some symptoms that indicate a tumor in the front portion of the brain.
- Personality changes,
- memory defects,
- gait disorders,
- speech difficulties
List some symptoms that indicate a tumor in the parietal regions of the brain.
- loss of vision,
- spatial disorientation,
- seizures.
What radionuclide is used in a PET scan.
FDG (Fluorodeoxyglucose).
It is known as a tracer. The tracer collects in areas of the body that have higher levels of chemical activity. Cancer cells show up as bright spots on PET scans because they have a higher metabolic rate than normal cells. (note: other noncancerous conditions can also look like cancers)
what is dubulking
reducing the size of a tumor
why are most patients with CNS tumors prescribed steroids
to reduce sweeling and subside symptoms
Why must the steroid dose be gradually decreased rather than stopped at once.
Because the body stops producing natural steroids when an abundance is found in the bloodstream and it needs to start producing it naturally again before being taken off completely.
craniospinal treatment involves treatment to what two areas
entire brain and spinal cord
craniospinal treatment is most commonly used in the treatment of what cancer
medulloblastoma
at what dose may temporary hair loss occur
2000-4000 cGy
dose that permanent hair loss may occur
greater than 4000 cGy
what are radiosensitizers
chemicals that enhance the lethal effects of radiation
which cells are most radioresistant, well oxygenated cells or less oxygenated cells
less ocygenated cells AKA hypoxic cells
