Chapter 32 WS

Question 1

What part of the brain do most CNS tumors occur.

Answer 1

cerebrum

Question 2

What is the most common classification of brain tumor.

Answer 2

glioma

Question 3

What are the functions of the cerebrum.

Answer 3

• Interpretation of sensory impulses and voluntary muscular activities;
• it is the center for memory, learning, reasoning, judgment, intelligence, and emotions

Question 4

what type of primary cancer is most commonly responsible for metastatic brain cancer

Answer 4

lung cancer

Question 5

Which hemisphere of the brain do most metastatic brain cancers occur.

Answer 5

cerebral hemispheres

Question 6

List some late effects of radiation therapy to the brains of children.

Answer 6

• 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.

Question 7

List three structures that are filled with CSF (cerebral spinal fluid).

Answer 7

ventricles, cancals, and subarachnoid space

Question 8

what secretes CSF

Answer 8

Ependymal cells secrete about .5 L of CSF each day into the ventricles. The ependymal cells line the choroid plexuses.

Question 9

What is the tentorium.

Answer 9

A fold of dura mater (the outer covering of the brain) that separates the cerebral and cerebellar hemispheres.

Question 10

What structures are located in the supratentorial region..

Answer 10

• The cerebral hemispheres,
• the sella, pineal,
• upper brainstem regions

Question 11

What structures are located in the infratentorial region.

Answer 11

• Brainstem,
• pons,
• medulla, and
• cerebellum

Question 12

Where does the blood supply for the brain come from.

Answer 12

Internal carotid arteries and vertebral arteries via the circle of Willis.

Question 13

primary source of enegery for brain cells

Answer 13

glucose

Question 14

where does the spinal cord end

Answer 14

L1-L2

Question 15

what does CSF look like

Answer 15

clear colorless fluid that resemebles water

Question 16

list some lipid soluble substances

Answer 16

• alcohol
• nicotine
• heroin

Question 17

list some water soluble substances

Answer 17

• glucose
• some amino acids
• sodium

Question 18

what substances can cross the BBB

Answer 18

Lipid soluble.

Water-soluble substances can as well if they have a carrier molecule to cross the barrier via active transport

Question 19

what is CSF composed of

Answer 19

• Proteins,
• glucose,
• urea (a compound formed in the liver and excreted by the kidney),
• salts.

Question 20

signs and symptoms of intracranial pressure

Answer 20

• Headaches,
• vomiting,
• lethargy,
• seizures, and
• neurologic symptoms.

Question 21

what is papilledema

Answer 21

edema of the optic disc

results from increased intracranial pressure

Question 22

List some symptoms that indicate a tumor in the front portion of the brain.

Answer 22

• Personality changes,
• memory defects,
• gait disorders,
• speech difficulties

Question 23

List some symptoms that indicate a tumor in the parietal regions of the brain.

Answer 23

• loss of vision,
• spatial disorientation,
• seizures.

Question 24

What radionuclide is used in a PET scan.

Answer 24

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)

Question 25

what is dubulking

Answer 25

reducing the size of a tumor

Question 26

why are most patients with CNS tumors prescribed steroids

Answer 26

to reduce sweeling and subside symptoms

Question 27

Why must the steroid dose be gradually decreased rather than stopped at once.

Answer 27

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.

Question 28

craniospinal treatment involves treatment to what two areas

Answer 28

entire brain and spinal cord

Question 29

craniospinal treatment is most commonly used in the treatment of what cancer

Answer 29

medulloblastoma

Question 30

at what dose may temporary hair loss occur

Answer 30

2000-4000 cGy

Question 31

dose that permanent hair loss may occur

Answer 31

greater than 4000 cGy

Question 32

what are radiosensitizers

Answer 32

chemicals that enhance the lethal effects of radiation

Question 33

which cells are most radioresistant, well oxygenated cells or less oxygenated cells

Answer 33

less ocygenated cells AKA hypoxic cells