Characterisation of a high resolution small field of view portable gamma camera

Abstract

A handheld, high-resolution small field of view (SFOV) pinhole gamma camera has been characterised using a new set of protocols adapted from standards previously developed for large field of view (LFOV) systems. Parameters investigated include intrinsic and extrinsic spatial resolution, spatial linearity, uniformity, sensitivity, count rate capability and energy resolution. Camera characteristics are compared to some clinical LFOV gamma cameras and also to other SFOV cameras in development.

Assessing good operating conditions for intraoperative imaging of melanoma sentinel nodes by a portable gamma camera

“…a ¼ a 0 expð À cdÞ (5) gave a c value equal to 0.152 cm À1 , quite close to the nominal value of the linear attenuation coefficient in water for 140 keV energy photons (m ¼ 0.154 cm À1 [23]). No significant variation in background counts was found with increasing CSD and source depth in water.…”

A scheme for assessing the performance characteristics of small field-of-view gamma cameras

“…The described procedures for evaluating SFOV performance parameters provide a more appropriate scheme for characterising SFOV systems. These are applicable to all detector and collimator set-ups, and have been shown to be effective in characterising a SFOV camera [27]. To ensure consistency and comparability the authors recommend their adoption for all SFOV systems.…”

“…The slit should be as narrow as possible; this technique has been successful with a slit of width 2 mm [27]. The edge should be perpendicular to the mask surface and straight to an accuracy of at least 10% of the intrinsic resolution of the detector.…”

Design and development of a dedicated portable gamma camera system for intra-operative imaging

“…Recently, several portable gamma camera designs have been proposed for SLN surgery in breast cancer patients [9,[11][12][13][14][15].…”