Long-term stability of CT number of water, image noise and tube voltage for a SIEMENS CT-simulator(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2017年第12期
- Page:
- 1232-1235
- Research Field:
- 医学影像物理
- Publishing date:
Info
- Title:
- Long-term stability of CT number of water, image noise and tube voltage for a SIEMENS CT-simulator
- Author(s):
- SHI Feiyue1; BAI Zhenglu2; QIN Wei1
- 1. Radiation Therapy Center, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, China; 2. Department of Medical Equipment, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, China
- Keywords:
- ; Keywords: CT-simulator; CT number of water; image noise; tube voltage; long-term stability
- PACS:
- R811.1
- DOI:
- DOI:10.3969/j.issn.1005-202X.2017.12.008
- Abstract:
- Abstract: Objective To evaluate the long-term stability of the CT number of water, image noise and tube voltage for a SIEMENS Sensation Open CT-simulator by analyzing the data from routine quality assurance measurements using water phantom. Methods SIEMENS Sensation Open CT-simulator was tested monthly by a water phantom and routine quality assurance program. We obtained the CT number of water, image noise and tube voltage when the nominal tube voltages was 120 or 140 kV. Statistical analysis was conducted on the test data of 34 months from July 2013 to April 2016. Results At the nominal tube voltages of 120 kV, the CT number of water for the first to the sixed slice (slice thickness: 4.8 mm) were (0.05±0.47), (0.75±0.36), (0.08±0.50), (-1.21±0.46), (-0.53±0.45) and (-0.62±0.45) HU, respectively; and at 140 kV, the corresponding CT number of water for six slices were (0.07±0.50), (1.01±0.42), (0.11±0.41), (-1.36±0.51), (-1.24±0.38) and (-1.01 ±0.45) HU, respectively. The image noises at the nominal tube voltages of 120 and 140 kV were (10.32±0.05) and (9.42±0.06) HU. When the nominal tube voltage was 120 kV, we detected 28 times of 119.8 kV (tube voltage) and 6 times of 120.0 kV; when the nominal tube voltage was 140 kV, we detected 18 times of 139.8 kV and 16 times of 139.6 kV. Conclusion The statistical data shows that in the 34 months, the CT number of water, image noise and tube voltage for SIEMENS CT-simulator are stable and meet the operating requirements.
Last Update: 2017-12-21