Difference between revisions of "Radiology Pearls"
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*Radsource is another good resource. | *Radsource is another good resource. | ||
*http://radiologyassistant.nl/ | *http://radiologyassistant.nl/ | ||
+ | |||
+ | =CT= | ||
+ | * Houndsfield units of -1000 = air, +1000 = bone | ||
=MRI= | =MRI= | ||
* Nomenclature: use "intensity". | * Nomenclature: use "intensity". | ||
− | * CSF is the easiest way to distinguish between T1 and T2. It is black in T1 and white in T2. Remember that 1 precedes 2 in the same way that black "precedes" white (i.e. no one says "white and black" when referring to gray scale images) | + | * CSF is the easiest way to distinguish between T1 and T2. It is black in T1 and white in T2. Remember that 1 precedes 2 numerically in the same way that black naturally "precedes" white linguisticly (i.e. no one says "white and black" when referring to gray scale images) |
* Good overview article of [https://pn.bmj.com/content/practneurol/6/5/318.full.pdf MRI principles]. | * Good overview article of [https://pn.bmj.com/content/practneurol/6/5/318.full.pdf MRI principles]. | ||
+ | * Nasal turbinates bright = MRI w/ contrast (per NSICU attending Vagnerova) | ||
==Sequences== | ==Sequences== | ||
*T1: pancreas (due to Mn2+ deposition in the pancreas), fat, protein, hemorrhage, melanin, and gadolinium. | *T1: pancreas (due to Mn2+ deposition in the pancreas), fat, protein, hemorrhage, melanin, and gadolinium. |
Latest revision as of 23:30, 23 September 2024
Resources
- https://www.radiologyeducation.com (links to most of the major radiology websites and a lot of free resources)
- eAnatomy is an excellent tool for understanding MRIs. It’s $30 a year (if you have a free membership, unclear which membership).
- Radsource is another good resource.
- http://radiologyassistant.nl/
CT
- Houndsfield units of -1000 = air, +1000 = bone
MRI
- Nomenclature: use "intensity".
- CSF is the easiest way to distinguish between T1 and T2. It is black in T1 and white in T2. Remember that 1 precedes 2 numerically in the same way that black naturally "precedes" white linguisticly (i.e. no one says "white and black" when referring to gray scale images)
- Good overview article of MRI principles.
- Nasal turbinates bright = MRI w/ contrast (per NSICU attending Vagnerova)
Sequences
- T1: pancreas (due to Mn2+ deposition in the pancreas), fat, protein, hemorrhage, melanin, and gadolinium.
- T2: fluid (excluding blood)
- DWI: bright areas are suspicious for infarcts, but can also be T2 shine-through. Dating the chronicity of infarcts can be done with T1 and T2.
- ADC: dark areas on ADC are infarcts, and should correlate with bright areas on DWI.
- GRE: In phase/Out of phase. Most sensitive for assessing iron deposits, steatosis.
- T2-star:
- FLAIR: heavily T2-weighted image which suppresses CSF