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

Existing protocols for assessing the performance characteristics of large field-of-view (LFOV) gamma cameras can be inappropriate and require modification for use with small field-of-view (SFOV) gamma camera systems. This communication proposes a generic scheme suitable for evaluating the performance characteristics of SFOV gamma cameras, based on modifications to the standard procedures of NEMA NU1-2007. Key differences in methodology between tests for LFOV and SFOV gamma cameras are highlighted along with the rationale for these changes. It is envisaged that this scheme will provide more appropriate methods for equipment characterisation, ensuring quality and consistency for all SFOV cameras.

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

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.

The re-use of irrigating equipment for flexible cystoscopy is not safe.

OBJECTIVE: To determine the incidence of fluid reflux from the lower urinary tract into the connecting tubing used for irrigation in patients undergoing flexible cystoscopy. PATIENTS AND METHODS: The study was conducted in 94 consecutive male and female patients attending routine outpatient flexible cystoscopy lists. A sensor was designed and constructed to determine the presence of any retrograde flow of irrigating fluid, and the volume of any reflux through the connecting tubing. The mean (sd) cystoscope internal channel volume was 2.56 (0.25) mL; the level of significant reflux was set at >/=2. 25 mL. RESULTS: Reflux of irrigating fluid occurred in 11 males (17%) and was significant in six (9%) of 65 male patients, with the irrigating fluid reservoir set at a height of 0.78 m above the patient's mid-coronal level. No reflux occurred in the 29 females studied. CONCLUSIONS: Significant reflux can occur in males and hence the connecting tubing should be regarded as contaminated. Infection-control measures must include the prevention of transmission of blood-borne infections, e.g. hepatitis B and C viruses, and human immunodeficiency virus, because of the risk that blood may contaminate urine, and they should be implemented in all cases regardless of patient risk factors. From the available evidence, flexible cystoscopy should always be performed with single-use irrigation systems.