IEC 61675-3:1998 pdf download – Radionuclide imaging devices – Characteristics and test conditions -Part 3: Gamma camera based wholebody imaging systems.
The object of this part of IEC 61675 is to specify test methods for describing the characteristics 01 GAMMA CAMERA BASED WHOLEBODY IMAGING SYSTEMS. As these systems are based on Anger type GAMMA CAMERAS this part of IEC 61675 should be read in conjuction with IEC 60789.
Two additional tests, scanning speed constancy, and system SPATIAL RESOLUTION without scatter, shall be performed. Measurement of system uniformity for wholebody imaging systems Is possible but difficult to perform because of the requirement for large and uniform sources Most of the potential problems that could affect uniformity will also affect the system resolution. and therefore such a uniformity lest is not included in this standard.
The test methods specified in this part of lEG 81675 have been selected to reflect as much as possible the clinical use of GAMMA CAMERA BASED WHOLEBOOY IMAGING SYSTEMS. It is intended that the test methods be carried out by manufacturers, thereby enabling them to describe the characteristics of GAMMA CAMERA BASED WNOLE8ODY IMAGING SYSTEMS.
1.2 Normative references
The following normative documents contain provisions which, through reference In this text, constitute provisions of this part of IEC 61675. At the time of publication, the editions indicated were valid. All normative documents are subject to revision, and parties to agreements based on this part of IEC 61675 are encouraged to investigate the possibility of applying the most recent editions of the normative document5 indicated below. Members of IEC and ISO maintain registers of currently valid International Standards.
IEC 60788:1984, Medical radiology — Terminology
IEC 60789:1992, CharacterIstics and test conditions of rad,onociide imaging devices — Anger type gamma cameras
lEG 61675-2: Radionuclide imaging devices — Characteristics and test conditions — Part 2:
Single photon emission computed tomographs
2 TermInology and definitions
For inc purposes of this part of EC 61675. the definItIons given fl fEC 60789 and EC 60788. and IEC 61675-2 (see annex A), and the following definition apply.
2.1
GAMMA CAMERA BASED WHOLEBODY IMAGING SYSTEM
equipment for scintigraphy. employing one or two DETECTOR HEAD(s). in which the image is formed by moving the DETECTOf1 HEADfS) and the object relative to each other and relating output information of Ihe RADIO4.OGICAL IMAGE
3.1.2 Source
The source shall be a POINT SOURCE attached to the COLLIMATOR at the centre of the field of view. The ACTIV1TV of the source shall be adjusted to yield a COUNT RATE between 10000 and 20 000 counts per second, through a 20 % analyzer wIndow. In the DETECTOR FIELD OF VIEW.
3.1.3 Data acquisItion and analysis
The scan speed and the acquisition matrix shall be in the range recommended for clinical use Two scans shall be performed along the full scanning length using different speeds. The image of the POINT SOURCE shall be recorded.
A profile through the image of the POINT SOURCE in the direction of the motion should yield a constant count value. This profile shall have a width between 20 mm and 30 mm in the direction perpendicular to the direction of motion, and shall contain at least 10 000 counts per pixel. The analysis shall exclude the areas at the ends of the prof lie which are affected by the spatial resolution in the scanning direction.
3.1.4 R.port
For the region of analysis, report a graph of the percent deviation from the mean count value In addition report the value of the maximum percent deviation from the mean. Any deviation greater than expected from Poisson statistics standard deviations is indicatve of non•uniform scanning motion and shall be stated. The COLUMATOR and the scan speeds used in performing the measurements shall be also reported.
3.2 SPATIAL RESOLUTION without scaler
SPATIAL RESOLUTION without scatter shall be measured parallel and perpendicular to the direction of motion, and expressed as FULL WIDTH AT HALF MAXIMUM FWHUI of the LiNE SPREAD FUNCTION.
