Evaluation of thyroid uptake, by administration of small activities of radioactive iodine (I or I), is a well-defined procedure. Nowadays, nuclear medicine departments are using scintillation cameras coupled to pinhole collimators to perform such studies. On the other hand, gamma probes, which are normally used in radioguided surgical procedures, can technically be used for measuring the thyroi...

BACKGROUND Sentinel lymph node (SLN) procedure is now a widely accepted method of LN staging in selected invasive breast cancers (unifocal, size </= 2 cm, clinically N0, without previous treatment). Complete axillary clearance is no longer needed if the SLN is negative. However, the oncological safety of this procedure remains to be addressed in randomized clinical trials. One main pitfall is t...

Introduction: Gamma cameras are proposed for online range verification and treatment monitoring in proton therapy.  An Analytical formula was derived and validated for sensitivity of a slit collimator based on the photon fluence concept. Methods: Fluence formulation was generalized for photons distribution function and solved for high-energy point sources. The...

SPECT images are observation data acquired by a gamma-camera following an orbit around the patient’s body, at regularly spaced angles. A reconstructed image is the discrete representation of a slice or cross-section of the isotope distribution within the patient, transversal to the gamma-camera rotation axis. Bayesian reconstruction methods have been extensively used to reconstruct medical imag...

The development of low profile gamma-ray detectors has encouraged the production of small field of view (SFOV) hand-held imaging devices for use at the patient bedside and in operating theatres. Early development of these SFOV cameras was focussed on a single modality-gamma ray imaging. Recently, a hybrid system-gamma plus optical imaging-has been developed. This combination of optical and gamm...

Several groups have reported the development of dual modality Gamma camera/optical imagers, which are useful tools for investigating biological processes in experimental animals. While previously reported dual modality imaging instrumentation usually employed a separated gamma camera and optical imager, we designed a detector using a position sensitive photomultiplier tube (PSPMT) that is capab...

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 characteristi...

pulse-width modulation records up to 28,000 Hz from an Anger camera without spatial or tern poral distortion and with less than 1 % data loss. Recording and playback may be made at any of five tape speeds: 3%, 71,4, 15, 30, 60 ips, each accommodating a different maximal count ing rate. Since only two of four recording tracks are used, the others are available for other in put. The replayed data...

Emission computed tomography (emission CT) and conventional planar gamma-camera imaging of the liver were compared in 242 patients with suspected metastatic spread to liver. Concordant data were obtained in 171 patients (71%). Single large lesions, multiple small lesions, and diffuse disease were accurately defined with this new radionuclide tomographic technique. The smallest lesion detected b...

Scintillation gamma cameras based on low-noise electron multiplication (EM-)CCDs can reach high spatial resolutions. For further improvement of these gamma cameras, more insight is needed into how various parameters that characterize these devices influence their performance. Here, we use the Cramer-Rao lower bound (CRLB) to investigate the sensitivity of the energy and spatial resolution of an...