Mechanical Imaging of the Breast

Abstract

In this paper, we analyze the physical basis for elasticity imaging of the breast by measuring breast skin stress patterns that result from a force sensor array pressed against the breast tissue. Temporal and spatial changes in the stress pattern allow detection of internal structures with different elastic properties and assessment of geometrical and mechanical parameters of these structures. The method entitled mechanical imaging is implemented in the breast mechanical imager (BMI), a compact device consisting of a hand held probe equipped with a pressure sensor array, a compact electronic unit, and a touchscreen laptop computer. Data acquired by the BMI allows calculation of size, shape, consistency/hardness, and mobility of detected lesions. The BMI prototype has been validated in laboratory experiments on tissue models and in an ongoing clinical study. The obtained results prove that the BMI has potential to become a screening and diagnostic tool that could largely supplant clinical breast examination through its higher sensitivity, quantitative record storage, ease-of-use, and inherent low cost.

Human vs. robotic tactile sensing: Detecting lumps in soft tissue

“…A second challenge is the subsequent computer processing of the transduced data to obtain useful information (tactile data processing). Approaches have included vision-based processing [6,26], neural networks [5], and solid mechanics modeling [9,10], but a rigorous comparison of methods is lacking. A final challenge is determining the most effective means for relaying the tactile information to a human user (tactile display).…”

Development of array piezoelectric fingers towards in vivo breast tumor detection

“…2(c), the bottom surface of the handheld unit was mostly flat to flatten out tissues surrounding the area under testing and make sure that the contact area of each of the four PEF was fully in contact with the tissue. Note that, because the PEFs were in a cantilever geometry, they had only one end fixed to the housing, which is different from sensors in "SureTouch" [38][39][40] that have all edges fixed to the housing of the device. This allowed the probe surface of a PEF at the free end of the cantilever to be free from the pressure exerted on the housing as long as the PEF was "recessed" from the bottom surface of the housing (see Fig.…”

“…[33][34][35][36][37] Increasingly researchers have sought to detect breast tumors by means of tissue stiffness contrast by mechanical 33,34,[38][39][40][41][42][43][44][45][46] or optical 47,48 means. Ultrasound elastography (UE) detects breast tumors by measuring the difference in the distribution of the echo times with and without applying pressure which is further analyzed with inversion simulations.…”

“…[49][50][51][52] Breast mechanical imager (BMI or "SureTouch") detects breast tumors with great promise by measuring the compressive stress distribution with a pressure sensor array followed by the inversion simulation anal- ysis. [38][39][40] In recent years, more studies were also aiming to detect breast tumors using mechanical means. For example, a new study used an indenter to measure the normal and lateral forces which were further analyzed by artificial neural network to differentiate hard inclusions from the surrounding matrix.…”

Simultaneous Compliance and Registration Estimation for Robotic Surgery

“…Instead, relative stiffness changes can be used to detect nodules, cysts, arteries, etc. Examples of works using relative stiffness changes for stiffness imaging include [14,20,5]. Since the exact value of the environment stiffness in not important and since we limit the palpation forces to levels associated with small deformations of the tissue we use a simple linear model of the environment stiffness.…”