Table 3 Attenuation correction techniques
From: PET/MRI: a frontier in era of complementary hybrid imaging
Technique | Merits | Demerits | References |
|---|---|---|---|
Dixon (MRI) | ● Distinguishes fat from water ● Localises uptake volume of PET ● Extracts the lung with segmentation | ● Limited usage for attenuation correction ● Needs different echo times ● Cannot be used for detection of bone | (Martinez-Möller et al. 2009; Hu et al. 2009; Schulz et al. 2011) |
UTE (MRI) | ● Aids in detection of bone region | ● Consumes extra time for MRI data acquisition ● Not applicable for whole body imaging | (Schulz et al. 2011; Keereman et al. 2010; Catana et al. 2010) |
Atlas &Template (MRI) | ● Faster process ● Minimal or no dosage is required | ● Causes anatomical abnormalities ● Not applicable for whole body imaging ● Certain FOV gets truncated ● Requires templates for coils | (Hofmann et al. 2008; Kops and Herzog 2013; Malone et al. 2011; Klein et al. 2010) |
Emission (PET) | ● Minimal or zero additional acquisition time. ● Uses TOF information also. | ● Less response to radionuclides such as FDG ● Requires templates for coils | (Nuyts et al. 1999; Defrise et al. 2012; Rezaei et al. 2012; Boellaard et al. 2014) |
Transmission (PET) | ● Primarily used for analysis of field of view | ● Needs additional dose of radionuclides ● The attenuation map is corrupted with noise ● The spatial resolution is minimal | (Berker et al. 2014; Mollet et al. 2012; Mollet et al. 2012; Mollet et al. 2014; Watson et al. 2013) |