accurately registered anatomic and functional images can be acquired in a single examination
Current designs constitute a CT scanner in tandem with a PET scanner, with a common patient bed for both systems. Although in most designs, the scanner appears externally to be a single device, internally there is little or no mechanical integration (Fig.12)
Limitations and advantages of anatomical and metabolic imaging:
Limitations of anatomical imaging include; inability to determine if a mass is benign or malignant, or to determine if enlarged lymph nodes contain cancer, unable to detect small tumor foci in lymph nodes or elsewhere, inability to determine whether a residual–recurrent abnormality present after treatment represents scar or tumor …show more content…
In addition, there are some issues regarding specificity, because 18F-FDG is taken up not only by many malignant tumors but also by sites of active inflammation and physiologically by some organs
Advantages of metabolic imaging; ability to distinguish viable metabolically active tissue from scars, potential to detect functional changes in response to chemo or radio-therapy before there is any change in clinical or radiological size of a mass and detection is dependent on the intensity of the signal rather than the lesion size
Fundamentals of PET/CT imaging
It is well known that there is increased transport of glucose into malignant cells and up-regulation of enzymatic activity resulting in increased tracer uptake. Combined PET/CT facilitates the separation of normal physiologic uptake from pathologic uptake, provides accurate localization of functional abnormalities, and decreases the incidence of false-positive and false-negative imaging studies
The CT serves three functions: (1) provides the anatomical correlation for the functional information, (2) the means for CT-based attenuation correction of the PET data and (3) provide clinical diagnostic-quality CT …show more content…
This enables the necessary counts or scintillation events required for image formation to be obtained in less time when LSO crystals are used, thereby significantly decreasing the scanning time and increasing patient through¬put. GSO has a lower effective atomic number than BGO and LSO crystals. GSO crys¬tals emit slightly more light than BGO and have a decay time of approximately 50
Current designs constitute a CT scanner in tandem with a PET scanner, with a common patient bed for both systems. Although in most designs, the scanner appears externally to be a single device, internally there is little or no mechanical integration (Fig.12)
Limitations and advantages of anatomical and metabolic imaging:
Limitations of anatomical imaging include; inability to determine if a mass is benign or malignant, or to determine if enlarged lymph nodes contain cancer, unable to detect small tumor foci in lymph nodes or elsewhere, inability to determine whether a residual–recurrent abnormality present after treatment represents scar or tumor …show more content…
In addition, there are some issues regarding specificity, because 18F-FDG is taken up not only by many malignant tumors but also by sites of active inflammation and physiologically by some organs
Advantages of metabolic imaging; ability to distinguish viable metabolically active tissue from scars, potential to detect functional changes in response to chemo or radio-therapy before there is any change in clinical or radiological size of a mass and detection is dependent on the intensity of the signal rather than the lesion size
Fundamentals of PET/CT imaging
It is well known that there is increased transport of glucose into malignant cells and up-regulation of enzymatic activity resulting in increased tracer uptake. Combined PET/CT facilitates the separation of normal physiologic uptake from pathologic uptake, provides accurate localization of functional abnormalities, and decreases the incidence of false-positive and false-negative imaging studies
The CT serves three functions: (1) provides the anatomical correlation for the functional information, (2) the means for CT-based attenuation correction of the PET data and (3) provide clinical diagnostic-quality CT …show more content…
This enables the necessary counts or scintillation events required for image formation to be obtained in less time when LSO crystals are used, thereby significantly decreasing the scanning time and increasing patient through¬put. GSO has a lower effective atomic number than BGO and LSO crystals. GSO crys¬tals emit slightly more light than BGO and have a decay time of approximately 50