Modern PACS of today are all able to store and display PET-CT scan and perform fusion as described here. http://appliedradiology.com/articles/applied-radiology-focus-understanding-multi modal-fusion-imaging We certainly have this in our Fujifilm PACS. I can see that Sectra, Carestream etc are also capable. There is no technical reason why the PET-CT scanners that acquire images for NHS patients are not considered a regular NHS modality and images are sent directly from the outsourced PET-CT scanner directly to referring hospital's PACS as soon as images are acquired. There is also no technical reason why reports from the outsourced PET-CT reports cannot be transferred using HL7 v2 messaging to the referring NHS hospital's RIS-PACS.