Abstract：
:We have developed two prototypes of portable gamma cameras for medical applications based on a previous prototype designed and tested by our group. These cameras use a CsI(Na) continuous scintillation crystal coupled to the new flat-panel-type multianode position-sensitive photomultiplier tube, H8500 from Hamamatsu Photonics. One of the prototypes, mainly intended for intrasurgical use, has a field of view of 44 x 44 mm2, and weighs 1.2 kg. Its intrinsic resolution is better than 1.5 mm and its energy resolution is about 13% at 140 keV. The second prototype, mainly intended for osteological, renal, mammary, and endocrine (thyroid, parathyroid, and suprarenal) scintigraphies, weighs a total of 2 kg. Its average spatial resolution is 2 mm; it has a field of view of 95 x 95 mm2, with an energy resolution of about 15% at 140 keV. The main advantages of these gamma camera prototypes with respect to those previously reported in the literature are high portability and low weight, with no significant loss of sensitivity and spatial resolution. All the electronic components are packed inside the mini gamma cameras, and no external electronic devices are required. The cameras are only connected through the universal serial bus port to a portable PC. In this paper, we present the design of the cameras and describe the procedures that have led us to choose their configuration together with the most important performance features of the cameras. For one of the prototypes, clinical tests on melanoma patients are presented and images are compared with those obtained with a conventional camera.
journal_name
Med Physjournal_title
Medical physicsauthors
Sánchez F,Fernández MM,Giménez M,Benlloch JM,Rodríguez-Alvarez MJ,García de Quirós F,Lerche Ch,Pavón N,Palazón JA,Martínez J,Sebastiá Adoi
10.1118/1.2358199subject
Has Abstractpub_date
2006-11-01 00:00:00pages
4210-20issue
11eissn
0094-2405issn
2473-4209journal_volume
33pub_type
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