Nuc Medicine Flashcards
(26 cards)
what is so different about nuclear medicine than other imaging modalities?
focus is on physiological function rather than anatomy
Functional MRI
CT/MR enterography
Doppler ultrasound
also have functional components
T-F nuclear imaging the body is imaged from the outside in?
false- inside out
T-F- side effects are very common in nuclear medicine?
false- extremely rare
radiation effects are so small they can not be measured
what is the most commonly used compound in nuclear medicine? what is its half life? what is special about it.
technetium 99m
6 hours
readily combines with various compounds
What iodine isotope is used for imaging? treatment?
123 imaging or uptake studies for thyroid
131- high energy, destroys tissue
The following is a list of common studies for nuclear medicine
Ventilation/Perfusion (V/Q) Myocardial Perfusion Imaging Renal scan Hepatobiliary and spleen imaging GI bleeding Meckel’s diverticulum scan GI motility study Infection imaging Thyroid/parathyroid imaging Skeletal imaging Imaging of neuroendocrine tumors Lymphoscintigraphy FDG-PET
T-F- skeletal seeking radiotracers depict osteoclastic activity and regional blood flow to bone? Is it specific?
false- osteoblastic
Non-specific: any cause of increased osteoblastic activity will lead to abnormal tracer uptake. However, it is highly sensitive.
What are common bone scan indications?
malignancy (not multiple myeloma) fractures osteomyelitis (three phase scan) benign bone tumors Paget's
Is a dexa scan a bone scan?
no- it uses x-rays to determine bone density
If a child has knee pain and it lights up on bone scan, what should we be thinking?
osteomyelitis
what should we think on a bone scan of vertical hot spots along the ribs?
multiple fractures likely trauma and very unusual for metastatic disease
on bone scan what should we think with a hot spot then a thickened hot streak going up the shin line
shin splints
on bone scan what should we think if there is a ton of bone looking material and mishaping an entire limb?
paget’s
Indium111 tagged WBC is used when?>
May be performed when infectious source cannot be determined
Then get more specific imaging
if uptake in LLQ think diverticulosis
Defects on VQ scan can be caused by pneumonia- so what else do we need to get
x-ray
myocardial perfusion imaging uses what predominantly?
Tc-99m tetrofosmin
review indications for myocardial perfusion imaging-
- Diagnosis of CAD (patient who might benefit from revascularization therapy)
- Diagnosis of acute MI
- Risk stratification after infarction
- Assessment of viable myocardium vs. scar in patients with chronic CAD
- Preoperative cardiac risk assessment
On cardiac perfusion what side is septal on?
left and lateral is on right
base is away from apex
in myocardial perfusion reversible defect- what is bright and what is dark?
stress= dark rest= light
What methodology gives the most info about esophageal gastric and intestinal motility
radionuclide scans
Hepatobiliary imaging uses what chemical?
Tc-99 iinodiacetic acid
dame uptake and transport as bilirubin- dependent on hepatic function
on nuclear imaging of hepatobiliary system what are signs of acute cholecystitis?
no gallbladder filling
dilated intrahepatic ducts
dilated CBD
normal bowel excretion
What are the two major diagnostic imaging modalities for acute cholecystitis/
US and cholescintigraphy
US sens and spec.> 90%
Review the TC-99m HIDA scan
Non-visualization (non-filling) of the GB by 60 minutes = cholecystitis
Then extend study for up to 4 hours
Non-visualization at 4 hours = ACUTE cholecystitis
If the gallbladder fills between 1 and 4 hours = possible CHRONIC cholecystitis
Can’t wait 4 hours? Use morphine
