NEURO TEST #1 UNIT #3 (USAHS)
QUESTIONS WITH COMPLETE
SOLUTIONS
How does bone/dense structures show up on conventional X-rays? - ANSWER -White =
hyper dense
How does air/less dense structures show up on conventional X-rays? - ANSWER -Black
= hypodense
How does immediate dense structures show up on conventional X-rays? - ANSWER -
Gray = isodense (CSF)
Density is expressed in what? - ANSWER -Hounsfield Units
HU = 0? - ANSWER -Water
HU = -1000? - ANSWER -Air
An acute abnormal finding with a CT would be? - ANSWER -Hyperdense b/c of blood
coagulation.
An acute abnormal finding one week post with a CT would be? - ANSWER -Isodense
An acute abnormal finding 2-3 weeks post with a CT would be? - ANSWER -Hypodense
Epidural hematoma - ANSWER -B/w dura mater and skull (lens/football shape)
Acute Subdural Hematoma - ANSWER -B/w dura mater and arachnoid/pia mater
(crescent)
Chronic subdural hematoma - ANSWER -Dark
What are the 3 most common imaging modalities? - ANSWER -CT, MRI, and
neruoangiography.
Most CT and MRI are? - ANSWER -2D slices
What are the 3 imaging planes? - ANSWER -Horizontal (axial), coronal, Sagittal
MRI scans are? - ANSWER -True horizontal slices
What was CT scan developed from? - ANSWER -Conventional Xray
, What does CT measure? - ANSWER -Density of tissues
What are the differences b/w CT and conventional Xray? - ANSWER -- Slices are
obtained simultaneously
- Multiple xray beams pass through pt from different angles.
- Densities are displayed as cross section image of head.
Acute hemorrhages show up as _______ on the CT? - ANSWER -Hyperdense (white)
Chronic hemorrhages show up as __________ on the CT? - ANSWER -Hypodense
(Dark)
Acute cerebral infarction cannot be seen on CT within? - ANSWER -First 6-12 hrs
Neoplasms may appear as? - ANSWER -Hypodense, hyperdense, or isodense
depending on type and stage.
Intravenous contrast dye cna help image? - ANSWER -Neoplasm disorders
What is mass effect? - ANSWER -Anything that distorts brain's usual anatomy by
displacement. (Edema, neoplasms, hemorrhages)
Mass effect can cause? - ANSWER -Compression of ventricular space, effacement of
sulk
Why is intravenous contrast used to show neoplasms and brain abscess? - ANSWER -It
contains iodine which is denser and appears white in the CT.
What structures take the IV contrast? - ANSWER -Arteries, venous sinus, chroid plexus,
dura
What is myleography? - ANSWER -CT scan combined with contrast
How are iodinated dye injected? - ANSWER -Into the CSF though a lumbar puncture.
Iodinated bye in a myelography enhances? - ANSWER -Visualization of nerve roots and
impingement of CSF space that may cause disc hernia.
When is myelogrpahy useful? - ANSWER -For pt. who can't receive MRI
What determines conversion b/w calculated density values and gray scale used for
display? - ANSWER -Window and level
Bone windows = ? - ANSWER -Skull
QUESTIONS WITH COMPLETE
SOLUTIONS
How does bone/dense structures show up on conventional X-rays? - ANSWER -White =
hyper dense
How does air/less dense structures show up on conventional X-rays? - ANSWER -Black
= hypodense
How does immediate dense structures show up on conventional X-rays? - ANSWER -
Gray = isodense (CSF)
Density is expressed in what? - ANSWER -Hounsfield Units
HU = 0? - ANSWER -Water
HU = -1000? - ANSWER -Air
An acute abnormal finding with a CT would be? - ANSWER -Hyperdense b/c of blood
coagulation.
An acute abnormal finding one week post with a CT would be? - ANSWER -Isodense
An acute abnormal finding 2-3 weeks post with a CT would be? - ANSWER -Hypodense
Epidural hematoma - ANSWER -B/w dura mater and skull (lens/football shape)
Acute Subdural Hematoma - ANSWER -B/w dura mater and arachnoid/pia mater
(crescent)
Chronic subdural hematoma - ANSWER -Dark
What are the 3 most common imaging modalities? - ANSWER -CT, MRI, and
neruoangiography.
Most CT and MRI are? - ANSWER -2D slices
What are the 3 imaging planes? - ANSWER -Horizontal (axial), coronal, Sagittal
MRI scans are? - ANSWER -True horizontal slices
What was CT scan developed from? - ANSWER -Conventional Xray
, What does CT measure? - ANSWER -Density of tissues
What are the differences b/w CT and conventional Xray? - ANSWER -- Slices are
obtained simultaneously
- Multiple xray beams pass through pt from different angles.
- Densities are displayed as cross section image of head.
Acute hemorrhages show up as _______ on the CT? - ANSWER -Hyperdense (white)
Chronic hemorrhages show up as __________ on the CT? - ANSWER -Hypodense
(Dark)
Acute cerebral infarction cannot be seen on CT within? - ANSWER -First 6-12 hrs
Neoplasms may appear as? - ANSWER -Hypodense, hyperdense, or isodense
depending on type and stage.
Intravenous contrast dye cna help image? - ANSWER -Neoplasm disorders
What is mass effect? - ANSWER -Anything that distorts brain's usual anatomy by
displacement. (Edema, neoplasms, hemorrhages)
Mass effect can cause? - ANSWER -Compression of ventricular space, effacement of
sulk
Why is intravenous contrast used to show neoplasms and brain abscess? - ANSWER -It
contains iodine which is denser and appears white in the CT.
What structures take the IV contrast? - ANSWER -Arteries, venous sinus, chroid plexus,
dura
What is myleography? - ANSWER -CT scan combined with contrast
How are iodinated dye injected? - ANSWER -Into the CSF though a lumbar puncture.
Iodinated bye in a myelography enhances? - ANSWER -Visualization of nerve roots and
impingement of CSF space that may cause disc hernia.
When is myelogrpahy useful? - ANSWER -For pt. who can't receive MRI
What determines conversion b/w calculated density values and gray scale used for
display? - ANSWER -Window and level
Bone windows = ? - ANSWER -Skull
