SPECT Single photon emission computed tomography
<p>Jun 26, 2013 06:38 PM
 
nucl med  tomogram  (gamma)
 
similar to nuc med scans using a gamma camera.
but provides 3d info.
 
SPECT about 1 cm resolution
 
SPECT:  cheaper than PET,  they use longer-lived , easily obtained isotopes than PET.
 
(PET higher res cuz  2 gamma in opposite direcitons at same time =>  better localization)
 
SPECT: gamma camera rotated around pt.
 
Application:  can be used to complement gama imaging where true 3d needed eg tumors,
infection, thyroid or bone.
 
SPECT can provide accurate location in 3dc for func cardiac or brain.
 
Tc99m  used in brain scale  (HMPAO)
 
74% sensit for dx of Alz Dis,  compared to 81% sens for clinical exam.
 
but claim is that it can differentiate Alz Dis from vascular dementia:
(Alz is a smooth loss and vascul dem is patch)
 
SPECT competes with FDG PET... but SPECT is cheaper (eqpt is available and isotope is cheaper);
 
FDG  must come from med cyclotron... has short 110 min half life  for F18.
 
pixel size is 3 to 6 mm depedning on res.
 
artifacts  due to mvmt;
 
can integrate SPECT with CT.
 
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