Table 2.

Outline of criteria for each category used in the hybrid modality review

Category	Criteria	Number of articles
Intraoperative modalities	Intraoperative and/or SFOV imaging with a single modality	250
Preoperative imaging for navigation	Preoperative imaging combined with intraoperative radioguided surgery EXCLUDED: cases with no combination or fusion of modalities, i.e. a preoperative SPECT/CT used to plan radioguided surgery with a non-imaging probe would not be included, but a preoperative SPECT/CT image combined with intraoperative imaging for navigation would be included	9
Hybrid probe development	The development or preclinical testing of hybrid probes/tracers for intraoperative imaging EXCLUDED: probes with insufficiently different modalities (i.e. gamma radiation at two energies) EXCLUDED: theranostic probes where the radio component is not intended for radioguided surgery EXCLUDED: hybrid probes designed for preclinical assessment purposes only	98
Clinical use of hybrid modalities	Clinical use of hybrid modalities EXCLUDED: the ‘hybrid’ use of a visible dye alongside a radioisotope in SLNB	32
Hybrid technologies	Examples of technologies for hybrid intraoperative imaging including developmental and phantom studies	36