Implantable Ultrasonic Imaging Assembly for Automated Monitoring of Internal Organs

Abstract

An implantable miniaturized imaging device can be attractive in many clinical applications. They include automated, periodic, high-resolution monitoring of susceptible organs for early detection of an anomalous growth. In this paper, we propose an implantable ultrasonic imager capable of online high-resolution imaging of a region inside the body. A feasibility analysis is presented, with respect to design of such a system and its application to online monitoring of tumor growth in deep internal organs. We use ultrasound (US) imaging technology, as it is safe, low-cost, can be easily miniaturized, and amenable for long-term, point-of-care (POC) monitoring. The design space of the proposed system has been explored including form factor, transducer specifications and power/energy requirements. We have analyzed the effectiveness of the system in timely detection of anomalous growth in a case study through software simulations using a widely-accepted ultrasonic platform (Field II). Finally, through experimental studies using medical grade phantoms and an ultrasound scanner, we have evaluated the system with respect to its major imaging characteristics. It is observed that interstitial imaging under area/power constraints would achieve significantly better imaging quality in terms of contrast sensitivity and spatial resolution than existing techniques in deep, internal body parts, while maintaining the automated monitoring advantages.

A mobile-enabled micro communication device for biosensing

“…Consequently, ultrasound is used for various medical purposes. Many medical imaging techniques use ultrasound for non-invasive diagnosis applications in which the echo of the transmitted ultrasound is analyzed to create an image of the target applications such as examining fetus development in women, scanning for tumors in breast cancer patients, and employing physiotherapy (PT) for purposes of producing heat in tissues [34,35]. This widespread use for imaging and medical purposes has led to the development of various types of ultrasound transducers.…”

“…Using a value of ΔQ = 6pC, which was achieved on a dimension of 1000 μm 2 [110] and using an ultra nano-capacitor with Ccap = 9nF of nanosize dimensions [111]. Using the above equations (35), (36), and (37), the maximum amount of energy that was calculated was approximately 800 pJ when Ccap was charged at Vg = 0.42 V, which needs approximately 2500 cycles.…”

Active implantable sensor powered by ultrasounds with application in the monitoring of physiological parameters for soft tissues

“…The physics of transdution in US is based on the piezoelectricity principle found in some materials that converts mechanical strains into an electric voltage and vice-versa. The type, size and arrangement of the ultrasonic transducer (or array) dictates the operational frequency (typically between 0.4 -10 MHz), penetration depth and apodization of the acoustic beam for the different imaging modalities offered by US [2]. Although massively used by clinicians in their practice, the acoustic beams are still to be explored for purposes other than imaging or therapy in the medical context, videlicet to operate remotely implanted sensors within the human body.…”

Front-End Receiver Architecture for Miniaturised Ultrasound Imaging

“…Advances in transducer technology, beamforming algorithms and electronics have paved the way for the development of efficient, flexible and portable ultrasound imaging systems. Ultra-miniaturised, wireless systems have been proposed such as capsule endoscopes [1], implantable ultrasound devices [2] and wearable ultrasound devices [3]. However, the translation of these ideas into practical hardware is exceedingly difficult due to the inherent area, power and bandwidth constraints of such systems.…”