TECHNICAL NOTESPhantom study of a new hand-held γ-imaging probe for radio-guided surgeryFerretti, Alicea,b; Chondrogiannis, Sotiriosa; Marcolongo, Adrianoc; Rubello, DomenicoaAuthor Information Departments of aNuclear Medicine bMedical Physics cGeneral Hospital Direction, ‘Santa Maria della Misericordia’ Hospital, Rovigo, Italy Correspondence to Alice Ferretti, Department of Medical Physics, ‘Santa Maria della Misericordia’ Hospital, Via Tre Martiri 140, 45100 Rovigo, Italy Tel: +39 0425 39 4430; fax: +39 0425 39 4434; e-mail: email@example.com Received June 26, 2012 Accepted September 10, 2012 Nuclear Medicine Communications: January 2013 - Volume 34 - Issue 1 - p 86-90 doi: 10.1097/MNM.0b013e32835a7ccd Buy Metrics Abstract In recent years, hand-held mini γ-cameras have been increasingly used to perform scintigraphic imaging during surgery. The aim of the present work was to evaluate the physical characteristics of a new high-sensitivity hand-held mini γ-camera through specific phantom measurements. To characterize the performances of the imaging probe Guardian2 hand-held γ-camera, we measured its sensitivity and depth transmission curve, the extrinsic spatial resolution and spatial linearity, the spatial uniformity, and the count-rate linearity. We also estimated its whole image quality through the contrast-to-noise ratio of four hot spheres (internal diameters ranging from 4.9 to 9.8 mm). The sensitivity of the imaging probe Guardian2 γ-camera was 204 counts/s/MBq; it had a high spatial resolution (2.5 mm FWHM at contact) and optimal linearity of counts (Pearson’s coefficient, R2=0.999). The integral uniformity was 12.0% in the useful field of view (FOV) and 8.8% in the central FOV, whereas the differential uniformity was 5.7% in the useful FOV and 4.0% in the central FOV. The system was able to detect and distinguish all four small spheres used for the whole quality test. The contrast-to-noise ratio was evaluated both at contact with the collimator and with a 5-cm-thick interposed Plexiglas slab. The γ-imaging probe that we evaluated demonstrated good performance, confidently allowing its use for specific clinical applications in radio-guided surgery. © 2013 Lippincott Williams & Wilkins, Inc.