SN EN 61223-2-6 : 1994

Introduction
1. Scope and object
1.1 Scope
1.2 Object
2. Normative references
3. Terminology
3.1 Degree of requirements
3.2 Use of terms
3.3 Definitions
4. General aspects of CONSTANCY TESTS
4.1 General conditions affecting test procedures
4.2 Establishment of BASELINE VALUES
4.3 Frequency of CONSTANCY TESTS
4.4 Identification of equipment, instrumentation and
     test conditions
4.5 Measured functional parameters
5. Test methods
5.1 NOISE, MEAN CT NUMBERS and UNIFORMITY
5.2 SPATIAL RESOLUTION
5.3 SLICE THICKNESS
5.4 Dose
5.5 Positioning of the PATIENT SUPPORT
6. Statement of compliance
Figures
1. Schematic representation of a test pattern used to
     check the constancy with respect to grey-scale
     reproduction
2. Schematic representation of a test pattern used to
     check the constancy with respect to geometry and
     line structure
3. Schematic representation of a crosshatched pattern
     used to carry out measurements with respect to
     geometry
4. Schematic representation of a test pattern used to
     check the constancy with respect to resolution
5. Schematic representation of a test pattern used to
     check the constancy with respect to colour-related
     aspects
6. Preventive measures to establish optimal working
     conditions in workstations
Annexes
A. Terminology - Index of terms
B. Example of a form for the standardized test report
C. Guidance on action to be taken
D. Rationale
     conditions
Annex ZA (normative) Other international publications
quoted in this standard with the references of the
relevant European publications

Gives assistance in performing CONSTANCY TESTS on a CT SCANNER. It applies to those components of CT SCANNERS which influence the image quality, PATIENT dose and positioning.