This paper describes the development of a hand-held gamma camera for
intraoperative surgical guidance that is based on silicon photomultiplier (SiPM)
technology. The camera incorporates a cerium doped lanthanum bromide (LaBr3:Ce)
plate scintillator, an array of 80 SiPM photodetectors and a two-layer parallel-hole
collimator. The field of view is circular with a 60 mm diameter. The disk-shaped camera
housing is 75 mm in diameter, approximately 40.5 mm thick and has a mass of only 1.4 kg,
permitting either hand-held or arm-mounted use. All camera components are integrated on a
mobile cart that allows easy transport. The camera was developed for use in surgical
procedures including determination of the location and extent of primary carcinomas,
detection of secondary lesions and sentinel lymph node biopsy (SLNB). Here we describe the
camera design and its principal operating characteristics, including spatial resolution,
energy resolution, sensitivity uniformity, and geometric linearity. The gamma camera has
an intrinsic spatial resolution of 4.2 mm FWHM, an energy resolution of 21.1 % FWHM at 140
keV, and a sensitivity of 481 and 73 cps/MBq when using the single- and double-layer
collimators, respectively.