Assessment of the performance of small field of view gamma cameras for sentinel node imaging. Issue 11 (November 2015)

• Record Type: Journal Article
• Authors: Ng, Aik Hao; Clay, David; Blackshaw, Patricia E.; Bugby, Sarah L.; Morgan, Paul S.; Lees, John E.; Perkins, Alan C.
• Is Part Of: Nuclear medicine communications. Volume 36:Issue 11(2015:Nov.)
• Publication Date: 2015-11
• Subjects: Nuclear medicine -- Periodicals; 616.07575
• DOI: 10.1097/MNM.0000000000000377
• Languages: English
• ISSNs: 0143-3636

Abstract

<abstract> <title> <x xml:space="preserve">Abstract</x> </title> <sec> <title>Objective</title> <p>To develop a method for the assessment of small field of view (SFOV) gamma cameras using a novel phantom designed to simulate the localization of sentinel nodes in the presence of a high-activity injection site.</p> </sec> <sec> <title>Materials and methods</title> <p>The phantom consisted of a cube-shaped acrylic glass support frame. Sixteen acrylic glass plates and nine bars were stacked within the frame to allow a variable configuration of the simulated node depth and node-to-injection site separation. Syringes filled with <sup>99m</sup>Tc were used to simulate activity at the injection site and node. Scintigraphic imaging was carried out and the images were assessed subjectively and quantitatively through calculation of the contrast-to-noise ratio. The detection performance of an SFOV gamma camera was then compared with that of a large field of view gamma camera.</p> </sec> <sec> <title>Results</title> <p>The detectability studies showed that the SFOV gamma camera could detect low activity in nodes by visual examination of images and with contrast-to-noise ratios ranging from 3 to 62. In particular, the phantom showed the limits of node detection using an SFOV gamma camera over activity ratios less than 1 : 100 and at depths below 45 mm with 25 mm of node-to-injection site separation. Visual subjective assessment of images acquired under the same conditions showed that the SFOV gamma camera was superior to a large field of view camera for the detection of nodes at a node-to-injection site separation of 25 mm.</p> </sec> <sec> <title>Conclusion</title> <p>A low-cost phantom has been designed and fabricated that provides a versatile method for the assessment of SFOV gamma cameras intended for sentinel node imaging.</p> </sec> </abstract>