Thoracic Imaging 2003 - Society of Thoracic Radiology

Table 1 Radiotracers:
MPI-SPECT
Thallium-201: very good uptake, washout, redistribution, viability
Tc-sestamibi (Cardiolite): good uptake, very little washout
Tc-tetrofosmin (Myoview): good uptake, very little washout, rapid background clearance.
Tc-teboroxime (Cardiotech): very high myocardial extraction fraction, very fast washout, no redistribution.
Tc-furofosmin: new agent, similar to tetrofosmin.
Tc-NOET: high extraction fraction, washes out and redistributes, suboptimal background clearance.
MPI-PET:
Rubidium-82: portable generator myocardial PET perfusion agent.
13 N-ammonia ( 13 NH3 ): good utility PET perfusion agent.
15 0-water ( 15 0-H2 0): short half life perfusion agent.
F-18-FDG: glucose metabolism and important viability agent.
Blood Pool:
Technetium-RBC: general nuclear medicine blood pool agent, radionuclide ventriculography (first pass, accurate
ejection fraction and wall motion study)
15 0-Carbon Monoxide (C 15 0): PET blood pool agent.
Infarct/Injury Avid:
Tc-PYP: SPECT agent, recently infarcted myocardium.
Indium-111 antimyosin antibody: recently infarcted myocardium and chronic injuries.
Tc-annexia: apoptosis SPECT imaging.
Hypoxia:
Tc-HL-91: directly labels hypoxic myocardium.
F-18-misonidazole: PET agent for hypoxic myocardium.
Neuroreceptor:
I-123 MIBG: presynaptic sympathetic agent.
11 C hydroxyephedrine (HED): presynaptic sympathetic PET agent.
11 C-CGP12177: beta adrenoreceptor PET agent.
F-18 dopamine: presynaptic noradrenaline precursor.
F-18 carazol: post-synaptic beta adrenoreceptor.
Fatty Acid Metabolism:
I-123-BMIPP: fatty acid metabolism SPECT agent.
11 C palmitate: fatty acid metabolism PET agent .
11 C acetate: oxidative metabolism PET agent.
Thrombosis:
Tc-peptides for GPIIb/IIIa receptors: activated platelet imaging.
Atherosclerotic Plague:
Indium-111 C2D3 antibody: antibody to proliferating smooth muscle cells in arterial walls.
F-18-FDG: metabolic imaging of developing atheromatous plaque.
METHODOLOGY:
Planar imaging utilizes standard gamma cameras with collimation
to acquire static or dynamic imaging. Planar Imaging is
used for first pass studies to evaluate right and left ventricular
function, with or without active stress. Planar imaging is also
utilized for left to right shunt quantification with gamma variate
analysis. Planar imaging can also be utilized to quantify right to
left shunts utilizing Tc-MAA to quantify the amount of systemic
uptake versus pulmonary uptake. Planar imaging is also
utilized in the anterior, LAO and left lateral positions for evaluation
of radionuclide ventriculography. This remains a highly
viable technique for accurate follow-up of left ventricular ejec-
tion fraction and wall motion analysis when following myocardial
function while patients are on cardiotoxic drugs or new cardiac
agents under development. ECG gated planar studies can
also be utilized for myocardial perfusion imaging of patients too
obese for SPECT tables or for portable imaging to I.C.U. areas.
Single photon emission computed tomography (SPECT) has
become the tomographic standard for imaging myocardial perfusion.
Multi-headed gamma cameras have been introduced
which improved count statistics and helped to reduce acquisition
time. Most protocols utilize 180º acquisitions rather than 360º
acquisition, since the heart is asymmetric within the chest and
posterior viewing has low count rate and attenuation abnormali-
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