Low Cost Handheld Tactile Imaging Device for Breast Cancer Screening

Palpation has been routinely used by physicians to diagnose diseases for centuries In Clinical Breast Examination CBE medical personnel screen for suspect lesions that are to fold stiffer than surrounding tissue by palpation using two or three fingers followed by precession about a fixed in contact area Typical pressure to avoid discomfort and also feel deeper palpable objects ranges from KPa However palpation is highly qualitative and subjective and it is not possible to follow progression in the morphological changes The goal of the proof of concept study is to develop an ergonomic low cost less than $ stethoscope like probe to capture tactile images during palpation The probe will be pressed at KPa pressure and a series of images will be recorded in real time by pivoting the probe over a fixed contact area of about in in a precession motion similar to CBE The studies will be performed over a well characterized physical model an artificial breast and a clinical test on humans The tactile image would be at a resolution of m to image mm features at mm depth from the surface with relative hardness of fold compared to the surrounding matrix Two key drivers for developing the technology are i digitizing CBE will offer a screening record between biannual mammogram exams for women below and in low income countries where accessibility to a mammogram is limited and ii the current digital CBE instruments with array of mm size sensors compared to proposed m size pixels require rubbing the device on the skin at constant pressure and speed to create an image by stitching together the frames potentially causing distortions smearing due to dynamics of the palpable features The grayscale of the image for the proposed device will be linear making the analysis quantitative to detect local hardness and score and track the palpation over time The low power of the device will allow connectivity to a USB port for power signal and imaging on a laptop computer or smart phone To image more complex body topography such as axillary and cervical lymph nodes the design will allow for interchangeable device heads of different sizes At the heart of the proposed device is a nm thick nanostructured film that converts pressure to electrical signal to form the tactile image The film is a stratified structure of a monolayer of Au nanoparticles interposed by nm thick polymer layers On pressing the film the electron tunneling current between the particles modulates to measure the local pressure There are two specific aims i develop an unpackaged device to prove the principle in terms of resolution sensitivity power requirement for USB connectivity and ability to image fold harder structures mm in size at depths of mm using a physical model and ii develop a handheld device for testing on artificial breast model and limited clinical study with de identified patients with breast pain complaints or who are scheduled for mammograms The preliminary and published results by PI indicate that the specified resolution sensitivity and performance are possible A US Patent was issued in Project Narrative Vajra Instruments will design and build an ergonomic stethoscope like device that will obtain tactile images in real time during palpation using a procedure similar to that used in manual CBE The tool will be a low power device that may be interfaced with a laptop computer or smart phone to save and process the images The nanodevice is scalable for mass production using standard manufacturing processes and materials used in the microelectronics industry