Is radionuclide transmission scanning obsolete for dual-modality PET/CT systems?

Excerpt

With the introduction of dual-modality PET/CT imaging, the nuclear medicine community is witnessing a revolution in its daily clinical practice. The hope is that this technology will alleviate the complexity of the clinical decision-making process and improve patient management [1]. Even though combined PET/CT units have been accepted commercially, the clinical benefits of and the need for these systems remain controversial [2] and are still being debated [3]. For example, PET alone provides enough information to resolve clinically relevant metabolic problems for many malignant diseases, offering a sensitivity and specificity in excess of 90%; some argue that an incremental improvement in specificity or sensitivity beyond that point probably cannot justify the cost of performing image fusion systematically for all patients on a routine basis. The marketing strategy of vendors (supported by many scientists) aiming to achieve wider diffusion of hybrid PET/CT technology in clinical practice is that the added value of combined units is well established and represents the ultimate solution for image co-registration, allowing appropriate combination of imaging technologies to yield useful fusion of functional and anatomical images [1]. It appears that more than 90% of last year’s PET sales were PET/CT; this is leading almost all scanner manufacturers to entirely replace PET-only scanners by combined PET/CT, a questionable choice according to some active researchers in the field [2]. Whereas combined PET/CT has many interesting features and offers many advantages compared with software approaches to image co-registration for patient diagnosis and image-guided radiation therapy, it is often argued that combined PET/CT is not the ultimate solution for image co-registration and will most likely not be considered a major breakthrough that revolutionised the paradigm of medical imaging [3]. …