Triple-rule-out CT yields even contrast enhancement
1/22/2007
By: Eric Barnes
Researchers in Florida have developed a triphasic multidetector-row CT (MDCT) method for ruling out the three most dangerous causes of chest pain. Their 64-slice CT protocol examines the coronary arteries, pulmonary arteries, and the aortic arch in a single pass, generating even contrast enhancement in all three regions.
The protocol can "rule out the three major causes of complications: coronary artery disease, pulmonary embolism and aortic dissection," said Dr. Norbert Wilke, a radiologist at the University of Florida, Jacksonville. "CT has been very effective, with high sensitivity and specificity in ruling out pulmonary embolism (PE) and aortic dissection. Our hypothesis was to develop a method (that) could reliably and robustly image the coronary arteries, the pulmonary arteries and the aorta."
Wilke discussed the results of his team's small study at the 2006 RSNA meeting in Chicago. His co-investigators were Dr. Minh Nguyen, Dr. Kiran Kareti, Christopher Klassen, and Dr. Ivan Avala.
The group scanned 11 patients (average age 50, average BMI 30.6, heart rate 50-60 bpm at scan) craniocaudally from the lung apices to the diaphragm using a Sensation 64-slice scanner (Siemens Medical Solutions, Malvern, PA).
The ECG-gated thoracic exam -- "basically a lung protocol," Wilke said, used 64 x 0.6-mm collimation, rotation time of 0.33 seconds, pitch 0.3, 120 kVp and 500-600 mAs depending on body habitus. The scan took 12-17 seconds, he said.
The bolus trigger's region of interest was set at the left atrium, with a threshold of 120 HU and a five-second delay to allow for table repositioning and patient breath-hold, according to Wilke.
"Most patients had been selected from the emergency department on the basis of acute chest pain and intermediate risk score for major coronary events," he said.
Iodinated contrast (Ultravist 370, Berlex Imaging, Wayne, NJ) was injected using a dual-syringe injector (Stellant D, Medrad, Indianola, PA) with an 18-gauge needle or larger in the antecubital vein. The biphasic injection consisted of 80 cc of contrast, followed by a 50 cc mixture (1:1) of contrast and saline, followed by 50 cc of saline alone, all injected at 5 cc/sec.
Contrast enhancement was substantially even across all three areas of interest, Wilke said. Anova analysis of the 11 studies showed no significant difference (p = 0.014) in the average Hounsfield unit value of the main pulmonary artery (380 HU), left pulmonary artery (382 HU), right pulmonary artery (381 HU), distal pulmonary arteries (354 HU), proximal left main artery (410 HU), and the proximal right coronary artery (382 HU).
A Wilcoxon unpaired test showed a significant difference (p = 0.03) in average Hounsfield unit value of the distal pulmonary arteries among the 11 studies using the new protocol (354 HU) compared to three studies using a traditional coronary CT angiography (CTA) protocol (HU 209).
There was no significant difference in the average Hounsfield unit value of the proximal left main artery (412 HU) and proximal right coronary artery (398 HU) among the 11 studies using the triple-rule-out protocol compared to three studies with a traditional coronary CTA protocol (416 HU), (411 HU), the team wrote in an accompanying abstract.
"With a dedicated biphasic injection protocol (80 cc contrast followed by 40 cc) you cannot afford to fill the right side of the heart -- it's basically washed out," Wilke said of the facility's traditional protocol. "With the triphasic protocol, you extend the injection; you see the curve of the right atrium, the filling of the right ventricle. We appreciate that we have at least a medium density increase in the right ventricle versus the dedicated protocol."
As for limitations, "if the heart rate is too fast, we don't get enough data for multisegmental reconstruction," he said.
The triple-rule-out method allows for cost-effective, rapid assessment of PE, coronary stenosis, and thoracic aortic dissection in ER patients with a single acquisition, he said.
The radiation dose is substantially lower than for three dedicated exams. The group calculated the average dose length product at 1,049, compared to about 400 for a dedicated PE exam, and about 1,004 for coronary CTA.
"The protocol is recommended in patients with acute chest pain, preferably emergency room patients who have been identified at intermediate risk for coronary artery disease, and also having the need to exclude PE and aortic dissection," Wilke said. "In this method, there is no compromise in Hounsfield units or enhancement patterns for all vascular territories. And the radiation dose is acceptable."
By Eric Barnes
AuntMinnie.com staff writer
January 22, 2007
主要是对比剂注射方法的改变，量增大了很多。因为先要用80cc的对比剂，然后追50cc按1:1比例的对比剂和盐水，然后追50cc的盐水。
对病人的肾功和心功能也提出了挑战。
如果有的战友也做三联检查，请交流你们是怎么打药的，扫描方面的细节。
本人已经认领,48小时未交出译文,请其他战友继续
实在不好意思,由于不是影象专业,译文中有许多不妥之处,还请这方面的专业人士指正,谢谢
Triple-rule-out CT yields even contrast enhancement
1/22/2007
By: Eric Barnes
Researchers in Florida have developed a triphasic multidetector-row CT (MDCT) method for ruling out the three most dangerous causes of chest pain. Their 64-slice CT protocol examines the coronary arteries, pulmonary arteries, and the aortic arch in a single pass, generating even contrast enhancement in all three regions.
佛罗里达的研究人员已经开展了一种三相多排探头 CT(MDCT)检测方法用以排除引起胸痛的三种最危险的原因。他们的64位CT诊断方法以单趟为单位检查了冠状动脉、肺动脉、和主动脉弓，并且在所有的三个区域进行了造影增强扫描。
The protocol can "rule out the three major causes of complications: coronary artery disease, pulmonary embolism and aortic dissection," said Dr. Norbert Wilke, a radiologist at the University of Florida, Jacksonville. "CT has been very effective, with high sensitivity and specificity in ruling out pulmonary embolism (PE) and aortic dissection. Our hypothesis was to develop a method (that) could reliably and robustly image the coronary arteries, the pulmonary arteries and the aorta."
该诊断结果能“排除三个主要并发症的主要原因：冠心病，肺栓赛和主动脉壁夹层形成”来自Jacksonville佛罗里达大学的 Dr. Norbert Wilke说。“CT的高灵敏性和高特异性在排除肺栓赛(PE)和主动脉壁夹层形成是非常有效地。我们的前提就是发展一种能够可靠和大致地使冠状动脉、肺动脉和主动脉显像的方法。”
Wilke discussed the results of his team's small study at the 2006 RSNA meeting in Chicago. His co-investigators were Dr. Minh Nguyen, Dr. Kiran Kareti, Christopher Klassen, and Dr. Ivan Avala.
Wilke在2006年芝加哥召开的北美放射学会上对他们研究组的少部分研究结果进行了讨论。与他一起研究的人员有Dr. Minh Nguyen, Dr. Kiran Kareti, Christopher Klassen, 和 Dr. Ivan Avala.
The group scanned 11 patients (average age 50, average BMI 30.6, heart rate 50-60 bpm at scan) craniocaudally from the lung apices to the diaphragm using a Sensation 64-slice scanner (Siemens Medical Solutions, Malvern, PA).
该研究组利用感觉64位扫描对11名患者（平均年龄50岁、体重指数30.6，扫描时心率50－60次/分）按头尾向从肺尖到膈进行了扫描。The ECG-gated thoracic exam -- "basically a lung protocol," Wilke said, used 64 x 0.6-mm collimation, rotation time of 0.33 seconds, pitch 0.3, 120 kVp and 500-600 mAs depending on body habitus. The scan took 12-17 seconds, he said.
心电图-gated？胸部检查――“主要用于肺的诊断” Wilke说，依据体型使用64 x 0.6mm瞄准？、0.33妙/转、0.3节距、120千伏峰位和500－600 mAs。
The bolus trigger's region of interest was set at the left atrium, with a threshold of 120 HU and a five-second delay to allow for table repositioning and patient breath-hold, according to Wilke.
根据Wilke 所说，The bolus？触发器感兴趣部位被放在左心房？，加上120 HU的阈值和5妙的延迟－主要考虑到平板复位和患者的呼吸暂停。
"Most patients had been selected from the emergency department on the basis of acute chest pain and intermediate risk score for major coronary events," he said.
“大多数患者是在急性胸痛的基础上从急诊科选来，过渡危险评分用于多数冠状疾病”他说。
Iodinated contrast (Ultravist 370, Berlex Imaging, Wayne, NJ) was injected using a dual-syringe injector (Stellant D, Medrad, Indianola, PA) with an 18-gauge needle or larger in the antecubital vein. The biphasic injection consisted of 80 cc of contrast, followed by a 50 cc mixture (1:1) of contrast and saline, followed by 50 cc of saline alone, all injected at 5 cc/sec.
碘化对比剂用一个18单位的双重注射的注射器或者更大从肘前静脉注入。双期注射包括80 cc的对比剂，然后是50cc对比剂和saline按1：1比例配成的混合剂，随后单独注射50cc saline，所有均已5cc/秒注射。
Contrast enhancement was substantially even across all three areas of interest, Wilke said. Anova analysis of the 11 studies showed no significant difference (p = 0.014) in the average Hounsfield unit value of the main pulmonary artery (380 HU), left pulmonary artery (382 HU), right pulmonary artery (381 HU), distal pulmonary arteries (354 HU), proximal left main artery (410 HU), and the proximal right coronary artery (382 HU).
造影增强大体上正好可以到达三个需要注意的部位，Wilke说。11项研究的方差分析(p = 0.014)显示肺动脉主干（380 HU）的平均Hounsfield单位值没有明显不同。
A Wilcoxon unpaired test showed a significant difference (p = 0.03) in average Hounsfield unit value of the distal pulmonary arteries among the 11 studies using the new protocol (354 HU) compared to three studies using a traditional coronary CT angiography (CTA) protocol (HU 209).
一项Wilcoxon不成对检验(p = 0.03)在11项利用新诊断方法(354 HU)的研究与三项利用传统冠状动脉CT血管造影进行对比之后，显示肺动脉远端（380 HU）的平均Hounsfield单位值有明显差别。
There was no significant difference in the average Hounsfield unit value of the proximal left main artery (412 HU) and proximal right coronary artery (398 HU) among the 11 studies using the triple-rule-out protocol compared to three studies with a traditional coronary CTA protocol (416 HU), (411 HU), the team wrote in an accompanying abstract.
该研究组在其附随的摘要中写道：11项利用三联排除诊断方法(354 HU)的研究与三项利用传统冠状动脉CT血管造影诊断方法(416 HU) (411 HU)进行对比之后，主动脉右侧基底(412 HU)和右冠状动脉基底(398 HU)的平均Hounsfield单位值没有明显差别。
"With a dedicated biphasic injection protocol (80 cc contrast followed by 40 cc) you cannot afford to fill the right side of the heart -- it's basically washed out," Wilke said of the facility's traditional protocol. "With the triphasic protocol, you extend the injection; you see the curve of the right atrium, the filling of the right ventricle. We appreciate that we have at least a medium density increase in the right ventricle versus the dedicated protocol."
“利用一个专用双期注射诊断方法（80cc增强，然后是40cc），你不可能努力使其填充心脏右侧—其基本上被冲干净了” Wilke提及传统设备时说。“利用三相诊断方法，你延长了注射；你就看到了右心房的曲线，填充了整个右心室。”与专用的诊断方法相比，我们庆幸我们至少有中密度增强。
As for limitations, "if the heart rate is too fast, we don't get enough data for multi segmental reconstruction," he said.
至于其局限性，他说，“如果心率太快的话，我们不会得到足够的多段图象重建。”
The triple-rule-out method allows for cost-effective, rapid assessment of PE, coronary stenosis, and thoracic aortic dissection in ER patients with a single acquisition, he said.
三重排除的方法考虑到了成本-效益，PE的快速评估，冠状动脉狭窄和单个采集的ER 患者的胸主动脉夹层形成，他说。
The radiation dose is substantially lower than for three dedicated exams. The group calculated the average dose length product at 1,049, compared to about 400 for a dedicated PE exam, and about 1,004 for coronary CTA.
放射量实际上比三种专用检查要低。该研究组计算出了平均剂量，与专用PE检查的大约400相比，其长度产量？？？是1,049，冠脉CTA大约是1，004。
"The protocol is recommended in patients with acute chest pain, preferably emergency room patients who have been identified at intermediate risk for coronary artery disease, and also having the need to exclude PE and aortic dissection," Wilke said. "In this method, there is no compromise in Hounsfield units or enhancement patterns for all vascular territories. And the radiation dose is acceptable."
“推荐那些有急性胸痛患者使用这项诊断方法，特别是急诊科里被鉴定出有过度到冠状动脉疾病风险的患者，而且也有必要排除掉肺栓塞和主动脉夹层形成” Wilke说。“在这个方法里，对于所有血管分布区来说，Hounsfield单位和增强模式没有中间物？？，并且辐射剂量是可以接受的。”
编译:
字数:1504
佛罗里达的研究人员已经开展了一种三相多排探头 CT(MDCT)检测方法用以排除引起胸痛的三种最危险的原因。他们的64位CT诊断方法以单趟为单位检查了冠状动脉、肺动脉、和主动脉弓，并且在所有的三个区域进行了造影增强扫描。
该诊断结果能“排除三个主要并发症的主要原因：冠心病，肺栓赛和主动脉壁夹层形成”来自Jacksonville佛罗里达大学的 Dr. Norbert Wilke说。“CT的高灵敏性和高特异性在排除肺栓赛(PE)和主动脉壁夹层形成是非常有效地。我们的前提就是发展一种能够可靠和大致地使冠状动脉、肺动脉和主动脉显像的方法。
Wilke在2006年芝加哥召开的北美放射学会上对他们研究组的少部分研究结果进行了讨论。与他一起研究的人员有Dr. Minh Nguyen, Dr. Kiran Kareti, Christopher Klassen, 和 Dr. Ivan Avala.
该研究组利用感觉64位扫描对11名患者（平均年龄50岁、体重指数30.6，扫描时心率50－60次/分）按头尾向从肺尖到膈进行了扫描。
心电图-gated？胸部检查――“主要用于肺的诊断” Wilke说，依据体型使用64 x 0.6mm瞄准？、0.33妙/转、0.3节距、120千伏峰位和500－600 mAs。
根据Wilke 所说，The bolus？触发器感兴趣部位被放在左心房？，加上120 HU的阈值和5妙的延迟－主要考虑到平板复位和患者的呼吸暂停。
“大多数患者是在急性胸痛的基础上从急诊科选来，过渡危险评分用于多数冠状疾病”他说。
碘化增强剂用一个18单位的双重注射的注射器或者更大从肘前静脉注入。双期注射包括80 cc的对比剂，然后是50cc对比剂和saline按1：1比例配成的混合剂，随后单独注射50cc saline，所有均已5cc/秒注射。
造影增强大体上正好可以到达三个需要注意的部位，Wilke说。11项研究的方差分析(p = 0.014)显示肺动脉主干（380 HU）的平均Hounsfield单位值没有明显不同。
一项Wilcoxon不成对检验(p = 0.03)在11项利用新诊断方法(354 HU)的研究与三项利用传统冠状动脉CT血管造影进行对比之后，显示肺动脉远端（380 HU）的平均Hounsfield单位值有明显差别。
该研究组在其附随的摘要中写道：11项利用三联排除诊断方法(354 HU)的研究与三项利用传统冠状动脉CT血管造影诊断方法(416 HU) (411 HU)进行对比之后，主动脉右侧基底(412 HU)和右冠状动脉基底(398 HU)的平均Hounsfield单位值没有明显差别。
“利用一个专用双期注射诊断方法（80cc增强，然后是40cc），你不可能努力使其填充心脏右侧—其基本上被冲干净了” Wilke提及传统设备时说。“利用三相诊断方法，你延长了注射；你就看到了右心房的曲线，填充了整个右心室。”与专用的诊断方法相比，我们庆幸我们至少有中密度增强。
至于其局限性，他说，“如果心率太快的话，我们不会得到足够的多段图象重建。”
三重排除的方法考虑到了成本-效益，PE的快速评估，冠状动脉狭窄和单个采集的ER 患者的胸主动脉夹层形成，他说。
放射量实际上比三种专用检查要低。该研究组计算出了平均剂量，与专用PE检查的大约400相比，其长度产量？？？是1,049，冠脉CTA大约是1，004。
“推荐那些有急性胸痛患者使用这项诊断方法，特别是急诊科里被鉴定出有过度到冠状动脉疾病风险的患者，而且也有必要排除掉肺栓塞和主动脉夹层形成” Wilke说。“在这个方法里，对于所有血管分布区来说，Hounsfield单位和增强模式没有中间物？？，并且辐射剂量是可以接受的。”
