Q2. What are the future works in "The clinical role of fusion imaging using pet, ct, and mr imaging" ?
130 A controversy arose recently regarding the future role of SPECT in the era of PET. Given that the role of any molecular imaging technology is established with respect to the benefits conveyed to patients, dual-modality imaging systems using PET as the key component are here to stay and will definitely maintain an exclusive standing in clinical diagnosis, the assessment of response to treatment, and the delivery of personalized treatments and targeted therapies.
Q3. What is the common criterion for a multimodality imaging approach?
24 A variety of rail-based, docking, and click-over concepts for correlating functional and anatomic images are also being considered with the goal of offering a more economic approach to multimodality imaging for institutions with limited resources.
Q4. What is the undesirable property of the statistical iterative reconstruction techniques?
An undesirable property of the statistical iterative reconstruction techniques including the popular maximum likelihood–expectation maximization (ML-EM) algorithm is that large numbers of iterations increase the noise content of the reconstructed PET images.
Q5. What is the role of anatomic information in the reconstruction of PET data?
The anatomic information also can be useful for many other tasks, including attenuation compensation, transmission-based scatter modeling, motion detection, and correction, introducing a priori anatomic information into reconstruction of the PET emission data and partial volume correction.
Q6. What are the common methods of estimating the magnitude and spatial distribution of Compton scattered events?
Although computationally intensive, more refined algorithms that use a patient-specific attenuation map, an estimate of the emission image, and Monte Carlo–based radiation transport calculations to estimate the magnitude and spatial distribution of Compton scattered events that would be detected have also been considered.
Q7. What is the common procedure for a preinjection transmission scan?
A preinjection transmission scan is usually performedon stand-alone PET scanners before tracer injection to reduce spillover of emission data into the transmission energy window, although post-injection transmission scanning protocols have been successfully used in the clinic with the use of contemporary PET scanners.
Q8. What are the main reasons for the development of scatter correction techniques?
The expanding diagnostic and therapeutic applications ofquantitative PET imaging have motivated the development of scatter correction techniques, which incorporate patient-specific attenuation maps derived from either transmission scans or CT imaging and the physics of interaction and detection of emitted photons to estimate the scatter magnitude and distribution accurately.
Q9. What is the role of multimodality imaging in the assessment of central nervous system disorders?
Multimodality imaging had a pivotal role in the assessment of central nervous system disorders such as seizures, Alzheimer’s and Parkinson’s disease, head injury, and inoperable brain tumors.
Q10. What is the role of imaging in clinical diagnosis?
clinical diagnosis is rarely done without imaging, which makes molecular imaging an essential component of the clinical decision-making tree.
Q11. What is the potential of a whole-body MR imaging system?
The system is being assessed in a clinical setting by exploiting the full potential of anatomic MR imaging in terms of high soft-tissue contrast sensitivity in addition to the many other possibilities offered by this modality, including blood oxygenation level dependant (BOLD) imaging, functional MR imaging, diffusion-weighted imaging, perfusion-weighted imaging, and diffusion tensor imaging.
Q12. What is the role of FDGPET in prostate cancer?
FDGPET has limited impact in many malignancies presenting with low FDG avidity (eg, prostate cancer, hepatic metastases, and associated lymph nodes), where more specific tracers should be used.
Q13. What is the way to control the noise characteristics of the unknown image?
The noise characteristics can be controlled by incorporating a prior distribution to describe the statistical properties of the unknown image and thus produce a posteriori probability distributions from the image conditioned upon the data.
Q14. What is the role of software-based image registration and fusion in clinical imaging?
AND FUSIONSoftware image fusion can be challenging to perform on a routine basis in the clinical setting because it requires exceptional digital communication in medicine (DICOM) connectivity, compatibility between the scanning protocols used by various imaging modalities, and outstanding collaboration between various clinical departments.
Q15. What is the procedure used for the correction of the MR image?
The procedure used follows the approach described by Matsuda and colleagues,121 which involves realigning the PET and MR image volumes followed by segmentingthe MR image into white and gray matter using the statistical parametric mapping (SPM5) segmentation toolbox.
Q16. What is the role of a tracer in the field of molecular imaging?
These tracers have clearly demonstrated the enormous potential of PET/CT as an emerging modality in the field of molecular imaging.
Q17. What is the potential of a whole-body PET/MR imaging system?
Such a systemwould allow one to exploit, in addition to the previously discussed applications, the power of MR spectroscopy to measure the regional biochemical content and to assess the metabolic status or the presence of neoplasia and other diseases in specific tissue areas.
Q18. What is the well-accepted criterion for the activity concentration of sources?
The well-accepted criterion is that one can accurately quantify theactivity concentration for sources having dimensions equal to or larger than twice the system’s spatial resolution measured in terms of its fullwidth-at-half-maximum (FWHM).
Q19. How many APD-based readouts have been implemented on a commercial preclinical?
51,52 APD-based readout has already been implemented on a commercial preclinical PET system, the LabPET scanner,53 10 years after the development of the first prototype based on this technology.