Lock-in Amplifier-Based Impedance Detection of Tissue Type Using a Monopolar Injection Needle

Kim Kim,Park Park,Abbasi Abbasi,Cho Cho

doi:10.3390/s19214614

Abstract

For successful intra-articular injection therapy, it is essential to accurately position the tip of the injection needle into the target joint area while administering the drug into the affected tissue. In this study, we investigated the feasibility of a monopolar injection needle and lock-in amplifier (LIA)-based impedance measurement system for detecting the tissue type where the needle tip is located. After positioning the monopolar injection needle tip into the dermis, hypodermis, or muscle layer of pork tissue, the electrical impedance was measured in the frequency range of 10 Hz to 10 kHz. We observed a difference in the results based on the tissue type where the needle was positioned (p-value < 0.01). Therefore, the monopolar injection needle with electrical impedance measurement can be used to improve intra-articular injection therapy through non-destructive and real-time monitoring of the needle position in the tissues.

Highlights

Intra-articular injection is an effective therapy for adhesive capsulitis and joint diseases such as rheumatoid arthritis and osteoarthritis [1–3]
To improve the intra-articular injection therapy, we investigated the feasibility of using a disposable monopolar injection needle, which is insulated everywhere except at the needle tip, to facilitate identification of the type of pork tissue using electrical impedance measurement
We showed that application of the monopolar injection needle with lock-in amplifier (LIA)-based impedance measurement facilitates the accurate positioning of the needle tip for improved intra-articular injection therapy

Summary

Introduction

Intra-articular injection is an effective therapy for adhesive capsulitis and joint diseases such as rheumatoid arthritis and osteoarthritis [1–3]. Novel alternative and supplemental methods are required to overcome the limitations of the traditional image-guided methods, as well as to improve the needle positioning and the intra-articular injection therapy. To improve the intra-articular injection therapy, we investigated the feasibility of using a disposable monopolar injection needle, which is insulated everywhere except at the needle tip, to facilitate identification of the type of pork tissue (dermis, hypodermis, or muscle) using electrical impedance measurement. We performed LIA-based impedance measurement of the pork tissue where the tip of the monopolar injection needle was inserted using US as well as a developed LabVIEW programmed user interface. We showed that application of the monopolar injection needle with LIA-based impedance measurement facilitates the accurate positioning of the needle tip for improved intra-articular injection therapy

Lock-in Amplifier-Based Impedance Measurement System

Electrical Impedance Measurement of Porcine Tissues

3.3.Results and Accuracy of

Electrical Impedance Measurement of Pork Tissue

Impedance Monitoring of the Monopolar Injection Needle Position

Conclusion