Development of a mechatronic guidance system for targeted ultrasound‐guided biopsy under high‐resolution positron emission mammography localization

Abstract

Image-guided needle biopsy of small, detectable lesions is crucial for early-stage diagnosis, treatment planning, and management of breast cancer. High-resolution positron emission mammography (PEM) is a dedicated functional imaging modality that can detect breast cancer independent of breast tissue density, but anatomical context and real-time needle visualization are not yet available to guide biopsy. We propose a mechatronic guidance system integrating an ultrasound (US)-guided core-needle biopsy (CNB) with high-resolution PEM localization to improve the spatial sampling of breast lesions. This paper presents the benchtop testing and phantom studies to evaluate the accuracy of the system and its constituent components for targeted PEM-US-guided biopsy under simulated high-resolution PEM localization. Methods: A mechatronic guidance system was developed to operate with the Radialis PEM system and a conventional US system. The system includes a user-operated guidance arm and end-effector biopsy device, integrating a US transducer and CNB gun, with its needle focused on a remote center of motion (RCM). Custom software modules were developed to track, display, and guide the end-effector biopsy device. Registration of the mechatronic guidance system to a simulated PEM detector plate was performed using a landmark-based method. Testing was performed with fiducials positioned in the peripheral and central regions of the simulated detector plate and registration error was quantified. Breast phantom experiments were performed under ideal detection and localization to evaluate for bias in the end-effector biopsy device. The accuracy of the complete mechatronic guidance system to perform targeted breast biopsy was assessed using breast phantoms with simulated lesions. Three-dimensional positioning error was quantified, and principal component analysis assessed for directional trends in 3D space within 95% prediction intervals. Targeted breast biopsies with test phantoms were performed and an overall in-plane needle targeting error was quantified. Results: The mean registration errors were 0.63 mm (N = 44) and 0.73 mm (N = 72) in the peripheral and central regions of the simulated PEM detector plate, respectively. A 3D 95% prediction ellipsoid shows an error volume <2.0 mm in diameter, centered on the mean registration error. Under ideal detection and localization, targets <1.0 mm in diameter can be sampled with 95% confidence. The complete mechatronic guidance system was able to successfully spatially sample simulated breast lesions, 4 mm and 6 mm in diameter and height (N = 20) in known 3D positions in the PEM image coordinate space. The 3D positioning error was 0.85 mm (N = 20) with 0.64 mm in-plane and 0.44 mm cross-plane component errors. Targeted breast biopsies resulted in a mean in-plane needle targeting error of 1.08 mm (N = 15) allowing for targets 1.32 mm in radius to be sampled with 95% confidence. Conclusions: We demonstrated the utility of our mechatronic guidance system for targeted breast biopsy under high...

Spatially tracked whole‐breast three‐dimensional ultrasound system toward point‐of‐care breast cancer screening in high‐risk women with dense breasts

“…20,[24][25][26][27][28] Additionally, ABUS can be used as an alternative imaging modality to second-look US examination to reliably detect lesions first identified on magnetic resonance imaging (MRI), which may improve clinical decision-making for imageguided breast biopsies, such as under US and MRI guidance, or alternative, novel methods for women with dense breasts, such as under high-resolution PEM-USguidance. 22,29,30 However, operator training for proper image acquisition, including correct patient position-ing, transducer placement, coupling to the breast and compression, is required to obtain high-quality ABUS images. 27,[31][32][33][34] Additionally, ABUS has been reported as uncomfortable and painful by some women during the imaging preparation and acquisition protocol, as extreme and anisotropic (increased) breast compression is required in denser areas of the breast to obtain reliable high-quality images.…”

“…ABUS (ABVS) has been shown to be useful as an adjunct to mammography for screening asymptomatic breast cancer in women with dense breasts, with comparable sensitivity and diagnostic performance accuracy to conventional HHUS 20,24–28 . Additionally, ABUS can be used as an alternative imaging modality to second‐look US examination to reliably detect lesions first identified on magnetic resonance imaging (MRI), which may improve clinical decision‐making for image‐guided breast biopsies, such as under US and MRI guidance, or alternative, novel methods for women with dense breasts, such as under high‐resolution PEM‐US‐guidance 22,29,30 . However, operator training for proper image acquisition, including correct patient positioning, transducer placement, coupling to the breast and compression, is required to obtain high‐quality ABUS images 27,31–34 .…”