Polhemus EM tracked Micro Sensor for CT‐guided interventions
Polhemus EM tracked Micro Sensor for CT‐guided interventions
复制标题
用于 CT 引导干预的 Polhemus EM 跟踪微型传感器
DOI：
10.1002/mp.13280
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发表时间：
2018
期刊：
影响因子：
3.8
通讯作者：
L. Maier
中科院分区：
文献类型：
--
作者：
A. Franz;A. Seitel;D. Cheray;L. Maier
目的
电磁跟踪是图像引导治疗中的关键技术。Polhemus公司推出了一种新型电磁微传感器;这是第一个通过跟踪器实现医疗器械定位的系统。Polhemus提供不同的场发生器（FG），其中一个几乎和方糖一样小。由于跟踪的准确性和鲁棒性是在临床环境中使用EM跟踪器的已知挑战，因此本研究的目标是在实验室（实验室）和计算机断层扫描（CT）环境中对微传感器进行标准化评估。
方法
通过Hummel等人评估微传感器。的标准化协议;结合Polhemus Liberty追踪器和3个FG（边长分别为1（TX 1）、2（TX 2）和4（TX 4）英寸）进行评估。在实验室和CT套件中确定精度以及位置和旋转精度。还测试了四种不同金属圆柱体的失真和两种典型医疗器械（皮下注射针和柔性内窥镜）的跟踪。
结果
在不同环境中，发现所有FG的抖动为0.02 mm或更小，但TX 2 FG除外，其在CT中无法获得有效数据。对于实验室中的所有FG，5 cm距离测量的误差为0.6 mm或更小。虽然TX 1 FG的距离误差在CT中仅略微增加至1.6 mm，但发现TX 4 FG的距离误差高达测量距离的约10%（平均5.4 mm）。实验室中TX 4/TX 2/TX 1 FG的平均定向误差为0.9° /0.5° /0.1°。在CT环境中，旋转误差在相同范围内：TX 4/TX 1 FG小于1.2° /0.1°。在大多数情况下，金属圆柱体存在下的偏差保持在1 mm以下。精度和定向精度似乎不受仪器跟踪的影响，并保持在与其他测量相同的范围内，而距离误差略有增加，最高可达1.7 mm。
结论
这项研究表明，使用新型微传感器可以精确跟踪医疗器械;它的抖动小于或等于0.01 mm，位置误差小于2 mm，旋转误差小于0.3°。与其他EM跟踪器一样，当临床环境中需要高达50 cm范围的大跟踪体积时，误差会增加。对于范围高达15 cm的较小跟踪体积，发现了高精度和鲁棒性。这对于可以轻松放置在感兴趣区域附近的TX 1 FG尤其有趣。
PURPOSE
Electromagnetic (EM) tracking is a key technology in image-guided therapy. A new EM Micro Sensor was presented by Polhemus Inc.; it is the first to enable localization of medical instruments through their trackers. Different field generators (FGs) are available by Polhemus, one being almost as small as a sugar cube. As accuracy and robustness of tracking are known challenges to using EM trackers in clinical environments, the goal of this study was a standardized assessment of the Micro Sensor in both a laboratory (lab) and a computed tomography (CT) environment.
METHODS
The Micro Sensor was assessed by means of Hummel et al.'s standardized protocol; it was assessed in conjunction with a Polhemus Liberty tracker and three FGs - with edge lengths of 1 (TX1), 2 (TX2), and 4 (TX4) inches. Precision as well as positional and rotational accuracy were determined in a lab and a CT suite. Distortions by four different metallic cylinders and tracking of two typical medical instruments - a hypodermic needle and a flexible endoscope - were also tested.
RESULTS
A jitter of 0.02 mm or less was found for all FGs in the different environments, except for the TX2 FG for which no valid data could be obtained in the CT. Errors of 5 cm distance measurements were 0.6 mm or less for all FGs in the lab. While the distance errors of the TX1 FG were only slightly increased up to 1.6 mm in the CT, those of the TX4 FG were found to be up to around 10% of the measured distance (5.4 mm on average). The mean orientation error was found to be 0.9° /0.5° /0.1° for the TX4/TX2/TX1 FG in the lab. In the CT environment, rotation errors were in the same range: less than 1.2° /0.1° for the TX4/TX1 FG. Deviation under the presence of metallic cylinders stayed below 1 mm in most cases. Precision and orientational accuracy do not seem to be affected by instrument tracking and stayed in the same range as for the other measurements whereas distance errors were slightly increased up to 1.7 mm.
CONCLUSION
This study shows that accurate tracking of medical instruments is possible with the new Micro Sensor; it demonstrated a jitter of 0.01 mm or less, position errors below 2 mm, and rotation errors of less than 0.3° . As with other EM trackers, errors increase when large tracking volumes with ranges of up to 50 cm are required in clinical environments. For smaller tracking volumes with ranges of up to 15 cm, a high accuracy and robustness was found. This is interesting especially for the TX1 FG which can easily be placed in close vicinity to the region of interest.
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影响因子：
10.6
作者：
Franz, Alfred M.;Haidegger, Tamas;Maier-Hein, Lena
通讯作者：
Maier-Hein, Lena
美国引导干预的电磁跟踪：新型紧凑型场发生器的标准化评估
DOI：
10.1007/s11548-012-0740-3
发表时间：
2012
影响因子：
3
作者：
Franz M;März K;Hummel J;Birkfellner W;Bendl R;Delorme S;Schlemmer HP;Meinzer H-P;Maier-Hein L
通讯作者：
Maier-Hein L
影响因子：
3.8
作者：
Maier-Hein, L.;Franz, A. M.;Meinzer, H. -P.
通讯作者：
Meinzer, H. -P.
DOI：
10.1007/s11548-013-0840-8
发表时间：
2013-07-01
影响因子：
3
作者：
Nolden, Marco;Zelzer, Sascha;Wolf, Ivo
通讯作者：
Wolf, Ivo