Radiology 6: Nuclear Medicine Flashcards
what is nuclear medicine?
branch of medicine and radiology that uses radioactivity for:
1) diagnostic imaging
2) therapy
what are forms of anatomical imaging?
X-ray
US
CT
MRI
what is nuclear medicine ?
nuclear medicine is functional imaging of physiological pathways at a molecular level and the affects of disease of these aka molecular imaging.
how does functional imaging work?
there is internal radiation which is detected by a camera and the radioactive decay process generates a functional image?
why is functional imaging good?
can detect patho-physiological changes of function/metabolism due to disease.
Earlier detection means earlier Rx
molecular events can be be quantified.
define the pharmaceutical
the compound which targets the physiological process in question
what are the targeting pharmaceuticals for tissue perfusion?
MAA
what are the targeting pharmaceuticals for glucose metabolism?
FDG
what are the targeting pharmaceuticals for bone metabolism?
MDP
what is the radio-isotope label?
attached to pharmaceutical and allows imaging of the distributionof the pharmaceutical.
how does nuclear medicine work?
atoms become radioactive when the configuration of protons and neutrons in the nucleus is unstable
a charged particle is emitted from the nucleus to gain stability.
commonly accompanied by the discahrge of excess energy gammy rays.
what is the radioisotope for tissue perfusion?
technetium-99m
what is the radioisotope for glucose metabolism?
flourine-18-FDG
what is the radioisotope for bone metabolism?
technetium-99m
what is the ideal radiopharmaceutical relationship?
targets physiological process suitable energy level for detection suitable half life low radiation dose easy radio-chemistry
what is is half life?
the time it takes to half
how can we administer radio-pharmaceutical?
IV Interstitial inhalation orally intra-vesical
what is the camera type for gamma rays ?
gamma camera
what is the camera type for positron emitters?
PET camera
what is SPE imaging?
this is a planar image that is taken with a gamma camera which provides dynamic imaging where the process happens
what is SPECT imaging?
data is collected from many angles around the patient providing depth
what are some examples?
bone, renal, infection, pulmonary, thyroid, cardiac, cancers
indications for bone scintigraphy
staging and diagnosis of bone mets unepxlained bone pain suspected bone and prosthetic joint infection sports injuries inflammatory arthropathy metabolic bone disease e.g. paget's
renal scintigraphy indications
assessment of outflow tract
measurement of differential renal function
diagnosis of reflux nephropathy
screening for reno-vasc disease
inflammatory/infective indication
Evaluation of inflammatory bowel disease
Diagnosis of chronic osteomyelitis and infected orthopaedic hardware
Diagnosis of soft tissue infection
Unexplained fever or raised inflammatory markers
V/Q indications
PE
thyroid scintigraphy indications
Graves disease and toxic nodules
myocardial perfusion scintigraphy
dx and mx of CAD
tumour imaging indication
Carcinoid
what is hybrid imaging ?
Imaging that combines anatomy with function
how does PET imaging works?
Uses radiopharmaceuticals that emit positrons during radio-active decay.
Positron annihilation with an electron generates 2 simultaneously emitted 511 kev gamma photons travelling in opposite directions
Co-incident detection by PET camera
which is the most common radiopharmaceutical ?
Most common is Fluorine-18-FDG
Glucose analogue
Goes to cells with a high glucose requirement (metabolism) i.e. tumour cells, infection/inflammation
when do we use PET scanning?
Oncology Cancer staging,restaging, residual/recurrent disease Cardiology Perfusion, hibernation assessment Neurology Alzheimers Vasculitis Active large vessel
