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Active ultrasound pattern injection system (AUSPIS) for interventional tool guidance.

Guo X, Kang HJ, Etienne-Cummings R, Boctor EM - PLoS ONE (2014)

Bottom Line: Accurate tool tracking is a crucial task that directly affects the safety and effectiveness of many interventional medical procedures.Compared to CT and MRI, ultrasound-based tool tracking has many advantages, including low cost, safety, mobility and ease of use.We performed ex vitro and in vivo experiments, showing significant improvements of tool visualization and accurate localization using different US imaging platforms.

View Article: PubMed Central - PubMed

Affiliation: Dept. of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, United States of America.

ABSTRACT
Accurate tool tracking is a crucial task that directly affects the safety and effectiveness of many interventional medical procedures. Compared to CT and MRI, ultrasound-based tool tracking has many advantages, including low cost, safety, mobility and ease of use. However, surgical tools are poorly visualized in conventional ultrasound images, thus preventing effective tool tracking and guidance. Existing tracking methods have not yet provided a solution that effectively solves the tool visualization and mid-plane localization accuracy problem and fully meets the clinical requirements. In this paper, we present an active ultrasound tracking and guiding system for interventional tools. The main principle of this system is to establish a bi-directional ultrasound communication between the interventional tool and US imaging machine within the tissue. This method enables the interventional tool to generate an active ultrasound field over the original imaging ultrasound signals. By controlling the timing and amplitude of the active ultrasound field, a virtual pattern can be directly injected into the US machine B mode display. In this work, we introduce the time and frequency modulation, mid-plane detection, and arbitrary pattern injection methods. The implementation of these methods further improves the target visualization and guiding accuracy, and expands the system application beyond simple tool tracking. We performed ex vitro and in vivo experiments, showing significant improvements of tool visualization and accurate localization using different US imaging platforms. An ultrasound image mid-plane detection accuracy of ±0.3 mm and a detectable tissue depth over 8.5 cm was achieved in the experiment. The system performance is tested under different configurations and system parameters. We also report the first experiment of arbitrary pattern injection to the B mode image and its application in accurate tool tracking.

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Degree of freedom (DOF) comparison between AUSPIS and beam steering method.a) Beam steering method requires the image plane to intersect the catheter line (the green line in figure a), the probe DOF is 4. b) The AUSPIS requires the image plane to intersect the AE element point (the green dot in figure b), the probe DOF is 5.
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pone-0104262-g018: Degree of freedom (DOF) comparison between AUSPIS and beam steering method.a) Beam steering method requires the image plane to intersect the catheter line (the green line in figure a), the probe DOF is 4. b) The AUSPIS requires the image plane to intersect the AE element point (the green dot in figure b), the probe DOF is 5.

Mentions: With single AE element, the AUSPIS provides 5 degrees of freedom to the probe, as shown in figure 18. It limits the image plane to intersect the AE element, which is a point. As a comparison, active beam-steering method constrains the image plane to intersect the catheter line, thus resulting in 4 degrees of freedom. In clinic, more DOFs mean less constraints on the probe position and orientation; this is especially important in applications like cardiac catheterization, in which doctors have to image from the very limited imaging window to avoid the ribs.


Active ultrasound pattern injection system (AUSPIS) for interventional tool guidance.

Guo X, Kang HJ, Etienne-Cummings R, Boctor EM - PLoS ONE (2014)

Degree of freedom (DOF) comparison between AUSPIS and beam steering method.a) Beam steering method requires the image plane to intersect the catheter line (the green line in figure a), the probe DOF is 4. b) The AUSPIS requires the image plane to intersect the AE element point (the green dot in figure b), the probe DOF is 5.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4206269&req=5

pone-0104262-g018: Degree of freedom (DOF) comparison between AUSPIS and beam steering method.a) Beam steering method requires the image plane to intersect the catheter line (the green line in figure a), the probe DOF is 4. b) The AUSPIS requires the image plane to intersect the AE element point (the green dot in figure b), the probe DOF is 5.
Mentions: With single AE element, the AUSPIS provides 5 degrees of freedom to the probe, as shown in figure 18. It limits the image plane to intersect the AE element, which is a point. As a comparison, active beam-steering method constrains the image plane to intersect the catheter line, thus resulting in 4 degrees of freedom. In clinic, more DOFs mean less constraints on the probe position and orientation; this is especially important in applications like cardiac catheterization, in which doctors have to image from the very limited imaging window to avoid the ribs.

Bottom Line: Accurate tool tracking is a crucial task that directly affects the safety and effectiveness of many interventional medical procedures.Compared to CT and MRI, ultrasound-based tool tracking has many advantages, including low cost, safety, mobility and ease of use.We performed ex vitro and in vivo experiments, showing significant improvements of tool visualization and accurate localization using different US imaging platforms.

View Article: PubMed Central - PubMed

Affiliation: Dept. of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, United States of America.

ABSTRACT
Accurate tool tracking is a crucial task that directly affects the safety and effectiveness of many interventional medical procedures. Compared to CT and MRI, ultrasound-based tool tracking has many advantages, including low cost, safety, mobility and ease of use. However, surgical tools are poorly visualized in conventional ultrasound images, thus preventing effective tool tracking and guidance. Existing tracking methods have not yet provided a solution that effectively solves the tool visualization and mid-plane localization accuracy problem and fully meets the clinical requirements. In this paper, we present an active ultrasound tracking and guiding system for interventional tools. The main principle of this system is to establish a bi-directional ultrasound communication between the interventional tool and US imaging machine within the tissue. This method enables the interventional tool to generate an active ultrasound field over the original imaging ultrasound signals. By controlling the timing and amplitude of the active ultrasound field, a virtual pattern can be directly injected into the US machine B mode display. In this work, we introduce the time and frequency modulation, mid-plane detection, and arbitrary pattern injection methods. The implementation of these methods further improves the target visualization and guiding accuracy, and expands the system application beyond simple tool tracking. We performed ex vitro and in vivo experiments, showing significant improvements of tool visualization and accurate localization using different US imaging platforms. An ultrasound image mid-plane detection accuracy of ±0.3 mm and a detectable tissue depth over 8.5 cm was achieved in the experiment. The system performance is tested under different configurations and system parameters. We also report the first experiment of arbitrary pattern injection to the B mode image and its application in accurate tool tracking.

Show MeSH