003 Urinary Tract Imaging - Basic Principles of CT, MRI, and Plain Film Imaging Flashcards
Absorbed dose for therapy is measured in units called gray (Gy);
1 rad = __ = 1 centigray (cGy)
Absorbed dose for therapy is measured in units called gray (Gy);
1 rad = 0.01 Gy = 1 centigray (cGy)
The amount of energy absorbed by a tissue for diagnostic purposes is referred to as the __ and is measured in sievert (Sv). Exposure of the eyes and gonads to radiation has a more significant biologic impact than exposure of other parts of the body. The occupational safety limit is __. Exposure time during fluoroscopy should be minimized by the use of short bursts of fluoroscopy; positioning the image intensifier as close to the patient as feasible substantially reduces scatter radiation.
The amount of energy absorbed by a tissue for diagnostic purposes is referred to a the EQUIVALENT DOSE and is measured in sievert (Sv). Exposure of the eyes and gonads to radiation has a more significant biologic impact than exposure of other parts of the body. The occupational safety limit is 50 mSv. Exposure time during fluoroscopy should be minimized by the use of short bursts of fluoroscopy; positioning the image intensifier as close to the patient as feasible substantially reduces scatter radiation.
There are four basic types of iodinated contrast media:
- __
- __
- __
- __
There are four basic types of iodinated contrast media:
- IONIC MONOMER
- NONIONIC MONOMER
- IONIC DIMER
- NONIONIC DIMER
__ are potentially fatal, are not dose dependent, and are more common in patients with a history of adverse reactions to contrast media, those with asthma or diabetes, those with impaired renal and cardiac function, and those on beta-adrenergic blockers.
IA REACTIONS are potentially fatal, are not dose dependent, and are more common in patients with a history of adverse reactions to contrast media, those with asthma or diabetes, those with impaired renal and cardiac function, and those on beta-adrenergic blockers.
It is common to have __, __, __, __, __, and occasionally __ after administration of contrast media.
It is common to have NAUSEA, FLUSHING, PRURITUS, URTICARIA, HEADACHE, and occasionally EMESIS after administration of contrast media.
Patients at high risk for adverse allergic reactions should be medicated with __, given 12 to 24 hours before the injection of contrast media, as well as __.
Patients at high risk for adverse allergic reactions should be medicated with STEROIDS, given 12 to 24 hours before the injection of contrast media, as well as ANTIHISTAMINES.
For __, it is useful to dilute contrast media by half with sterile saline, which facilitates identifying filling defects in the collecting system. There is a low risk of contrast reactions in patients in whom a retrograde or loopogram is performed.
For RETROGRADE PYELOGRAPHY, it is useful to dilute contrast media by half with sterile saline, which facilitates identifying filling defects in the collecting system. There is a low risk of contrast reactions in patients in whom a retrograde or loopogram is performed.
__ does not need to be held before contrast administration in a patient with normal renal function and no comorbidities.
METFORMIN does not need to be held before contrast administration in a patient with normal renal function and no comorbidities.
The risk of developing __ is increased in patients with decreased renal function (GFR < 60mL/min), diabetes mellitus, dehydration, advanced age, congestive heart failure, liver disease, and cardiac ejection fraction less than 40%.
The risk of developing CONTRAST-INDUCED NEPHROPATHY is increased in patients with decreased renal function (GFR < 60mL/min), diabetes mellitus, dehydration, advanced age, congestive heart failure, liver disease, and cardiac ejection fraction less than 40%.
__ is primarily filtered by the glomerulus. It is a good agent to assess renal function.
TcDTPA is primarily filtered by the glomerulus. It is a good agent to assess renal function.
Because __ is both filtered by the glomerulus and secreted by the proximal tubule, it localizes in the renal cortex and is a good agent for assessing cortical scarring and ectopic renal tissue.
Because TcDMSA is both filtered by the glomerulus and secreted by the proximal tubule, it localizes in the renal cortex and is a good agent for assessing cortical scarring and ectopic renal tissue.
__ is cleared mainly by tubular secretion; it has a limited ability to access renal function.
TcMAG3 is cleared mainly by tubular secretion; it has a limited ability to access renal function.
A T1/2 less than 10 minutes suggests an __. A T1/2 greater than 20 minutes is consistent with __.
A T1/2 less than 10 minutes suggests an UNOBSTRUCTED SYSTEM. A T1/2 greater than 20 minutes is consistent with RENAL OBSTRUCTION.
A positive bone scan is/is not specific for cancer. Moreover, the volume of cancer cannot be quantitated on bone scan. Patients with widely metastatic disease may have diffuse uptake (hyper scan) and no discrete lesions.
A positive bone scan IS NOT specific for cancer. Moreover, the volume of cancer cannot be quantitated on bone scan. Patients with widely metastatic disease may have diffuse uptake (hyper scan) and no discrete lesions.
__, __, and __ have been used as imaging agents for PET scans.
GLUCOSE, CHOLINE, and AMINO ACIDS have been used as imaging agents for PET scans.
