Hersh Desai, Abstract Co-Author: Nothing to Disclose

ravi mahadevan, Abstract Co-Author: Nothing to Disclose

Jackson Bruce Morton BS, Abstract Co-Author: Nothing to Disclose

Matt Nagle, Abstract Co-Author: Nothing to Disclose

Mark Palmeri MD, PhD, Abstract Co-Author: Nothing to Disclose

Paul Vincent Suhocki MD, Presenter: Nothing to Disclose

Percutaneous cholangiography technique has changed little over the decades and is associated with prolonged fluoroscopy times. The purpose of this research was to develop a needle prototype that would reduce procedure time and, therefore, radiation exposure to the patient and operator.

The needle prototype was created from an 18 gauge needle shaft and a 20 gauge stylet, separated by an insulating layer of non-conductive polyurethane and glue. Current travels from the tip of the 18 gauge needle shaft, across surrounding fluid and into the stylet tip. The needle functions as a leg of a Wheatstone Bridge, with the fluid at the needle tip acting as a variable resistor. It utilizes a BeagleBone Black microprocessor for its software computational needs. The BeagleBone Black stores a Python based code.  Battery, circuit and microprocessor are housed inside a box equipped with USB and HDMI outputs for data display. The output is compatible with most medical display monitors and continuously updates output voltage values. The needle was tested in-vitro, using salt and deionized water solutions of differing electrical conductivities matching those of blood, bile and liver.

This needle prototype successfully transduced changes in relative electrical conductivity in fluids surrounding the needle tip. It accurately detected entry of the needle tip into a salt solution that has the same conductive properties as bile. In the range of biologically relevant conductivities, generally below 2 S/m, the response of the system allowed for differentiation between the electrical conductivities of bile, blood and liver tissue.  

This percutaneous cholangiography needle prototype utilizes the unique electrical conductivity properties of bile to alert the operator that the needle tip has entered a bile duct. Further testing in animal models will be necessary before determining its clinical utility for this and other applications.

This needle prototype can reduce radiation exposure associated with percutaneous transhepatic cholangiography by eliminating the need for fluoroscopy during much of the procedure. This technology shows potential for use in other medical procedures as well, utilizing the unique electrical conductivities of body fluids not discussed here.

Desai, H, mahadevan, r, Morton, J, Nagle, M, Palmeri, M, Suhocki, P, A Percutaneous Transhepatic Cholangiography Needle Prototype That Utilizes the Unique Electrical Conductivity of Bile to Alert the Operator That the Needle Tip Has Entered a Bile Duct.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14005713.html