Dose estimation and quality control in computed tomography (CT) scanners are useful in controlling the dose of radiation given to patients while tests are carried out. The study was performed in a 16-slice Computed To...Dose estimation and quality control in computed tomography (CT) scanners are useful in controlling the dose of radiation given to patients while tests are carried out. The study was performed in a 16-slice Computed Tomography (CT) system of LightSpeed RT16 Xtra CT scanner. Quality control was done using a vendor-provided QA Phantom, and the six aspects of image quality were measured. For CT dosimetry, Computed Tomography Dose index volume (CTDIvol) was performed using Computed Tomography Dose Index (CTDI) Phantom. CTDI Phantom consists of three parts: Pediatric Head, Adult Head, and Adult Body Phantom. A 10 cm long pencil ion chamber DCT-10 was used to measure the dose at different positions inside the CTDI Phantom. Data were collected using MagicMax Universal software. For dose estimation of the CTDIvol Report of AAPM Task Group, 96 and 111 formalisms were used. For Pediatric Head, Adult Head, and Adult Body Phantom the measured CIDIvol was 61.04 mGy, 48.11 mGy, and 18.08 mGy respectively. The study has shown deviations of 7%, 15%, and 19% between estimated and console-displayed doses for Pediatric Head, Adult Head, and Adult Body scan techniques respectively. The six aspects of image quality measured by QA Phantom were found to be compatible with the specifications of the machine and CTDIvol measured by CTDI Phantom were found within a tolerance limit of ±20%. Hence, the QC and dosimetry of the mentioned machine are within the limit.展开更多
1故障现象每次启动扫描时,扫描桌面状态区均红字显示：＂The detector is not theproper temperature,detector temperatureis high,if continue to scan,the imagequality may be affected.＂,即：探测器温度不在正常范围内,温度较高,...1故障现象每次启动扫描时,扫描桌面状态区均红字显示：＂The detector is not theproper temperature,detector temperatureis high,if continue to scan,the imagequality may be affected.＂,即：探测器温度不在正常范围内,温度较高,如果继续扫描,图像质量可能会受到影响。如果忽视此错误继续扫描,则扫描3~5名患者后状态区显示：＂DAS Digital ModuleTemperature Out of Tolerance,the detec-tor temperature is too high,the scan is notallowed.＂展开更多
1影像重建服务器故障
1.1故障现象
在患者扫描过程中,控制台监视器不能显示扫描后图像,提示＂Reconstruc-tion process has stopedd.Scaning is pos-sible but no images will be made.Restartthe systm.＂（重建进程被中止。允许扫...1影像重建服务器故障
1.1故障现象
在患者扫描过程中,控制台监视器不能显示扫描后图像,提示＂Reconstruc-tion process has stopedd.Scaning is pos-sible but no images will be made.Restartthe systm.＂（重建进程被中止。允许扫描但没有图像建立。请重启系统）。重启机器后,工作正常。展开更多
文摘Dose estimation and quality control in computed tomography (CT) scanners are useful in controlling the dose of radiation given to patients while tests are carried out. The study was performed in a 16-slice Computed Tomography (CT) system of LightSpeed RT16 Xtra CT scanner. Quality control was done using a vendor-provided QA Phantom, and the six aspects of image quality were measured. For CT dosimetry, Computed Tomography Dose index volume (CTDIvol) was performed using Computed Tomography Dose Index (CTDI) Phantom. CTDI Phantom consists of three parts: Pediatric Head, Adult Head, and Adult Body Phantom. A 10 cm long pencil ion chamber DCT-10 was used to measure the dose at different positions inside the CTDI Phantom. Data were collected using MagicMax Universal software. For dose estimation of the CTDIvol Report of AAPM Task Group, 96 and 111 formalisms were used. For Pediatric Head, Adult Head, and Adult Body Phantom the measured CIDIvol was 61.04 mGy, 48.11 mGy, and 18.08 mGy respectively. The study has shown deviations of 7%, 15%, and 19% between estimated and console-displayed doses for Pediatric Head, Adult Head, and Adult Body scan techniques respectively. The six aspects of image quality measured by QA Phantom were found to be compatible with the specifications of the machine and CTDIvol measured by CTDI Phantom were found within a tolerance limit of ±20%. Hence, the QC and dosimetry of the mentioned machine are within the limit.
文摘1故障现象每次启动扫描时,扫描桌面状态区均红字显示：＂The detector is not theproper temperature,detector temperatureis high,if continue to scan,the imagequality may be affected.＂,即：探测器温度不在正常范围内,温度较高,如果继续扫描,图像质量可能会受到影响。如果忽视此错误继续扫描,则扫描3~5名患者后状态区显示：＂DAS Digital ModuleTemperature Out of Tolerance,the detec-tor temperature is too high,the scan is notallowed.＂
文摘1影像重建服务器故障
1.1故障现象
在患者扫描过程中,控制台监视器不能显示扫描后图像,提示＂Reconstruc-tion process has stopedd.Scaning is pos-sible but no images will be made.Restartthe systm.＂（重建进程被中止。允许扫描但没有图像建立。请重启系统）。重启机器后,工作正常。
