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Brian MacConaghy

Physicist IV






Non-invasive Treatment of Abscesses with Ultrasound

Abscesses are walled-off collections of fluid and bacteria within the body. They are common complications of surgery, trauma, and systemic infections. Typical treatment is the surgical placement of a drainage catheter to drain the abscess fluid over several days. Dr. Keith Chan and researchers at APL-UW's Center for Industrial + Medical Ultrasound are exploring how to treat abscesses non-invasively, that is, from outside the body, with high-intensity focused ultrasound (HIFU). This experimental therapy could reduce pain, radiation exposure, antibiotic use, and costs for patients with abscesses. Therapeutic ultrasound could also treat abscesses too small or inaccessible for conventional drainage.

20 Jun 2016

Flow Cytometry Techniques Advance Microbubble Science

Researchers at the Center for Industrial and Medical Ultrasound (CIMU) are measuring the physical properties of ultrasound contrast agents — tiny gas bubbles several microns in diameter used to increase sonogram imaging efficiency in the body. When injected to the general circulation they can act as probes and beacons within the body, and can carry and deploy chemotherapeutic payloads.

CIMU researchers have developed a hybrid instrument that combines an off-the-shelf flow cytometer with an acoustic transducer. The cytometer's laser interrogation counts and measures the bubbles while the acoustic interrogation reveals the bubbles' viscosity and elasticity at megahertz frequencies.

5 Dec 2013


2000-present and while at APL-UW

An ultrasonic caliper device for measuring acoustic nonlinearity

Hunter, C., O.A Sapozhnikov, A.D. Maxwell, V.A. Khokhlova, Y.-N. Wang, B. MacConaghy, and W. Kreider, "An ultrasonic caliper device for measuring acoustic nonlinearity," Phys. Procedia, 87, 93-98, doi:10.1016/j.phpro.2016.12.015, 2016.

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1 May 2016

In medical and industrial ultrasound, it is often necessary to measure the acoustic properties of a material. A specific medical application requires measurements of sound speed, attenuation, and nonlinearity to characterize livers being evaluated for transplantation. For this application, a transmission-mode caliper device is proposed in which both transmit and receive transducers are directly coupled to a test sample, the propagation distance is measured with an indicator gage, and receive waveforms are recorded for analysis. In this configuration, accurate measurements of nonlinearity present particular challenges: diffraction effects can be considerable while nonlinear distortions over short distances typically remain small. To enable simple estimates of the nonlinearity coeffcient from a quasi-linear approximation to the lossless Burgers’ equation, the calipers utilize a large transmitter and plane waves are measured at distances of 15–50 mm. Waves at 667 kHz and pressures between 0.1 and 1 MPa were generated and measured in water at different distances; the nonlinearity coeffcient of water was estimated from these measurements with a variability of approximately 10%. Ongoing efforts seek to test caliper performance in other media and improve accuracy via additional transducer calibrations.

Assessing the mechanism of kidney stone comminution by a lithotripter shock pulse

Sapozhnikov, O.A., M.R. Bailey, A.D. Maxwell, B. MacConaghy, R.O. Cleveland, and L.A. Crum, "Assessing the mechanism of kidney stone comminution by a lithotripter shock pulse," Proceedings, American Institute of Physics Conference, number 754, 164-166, doi:10.1063/1.1901627, (2005).

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28 Mar 2005

Comminution of axisymmetric stones by a lithotripter shock wave was studied experimentally and theoretically. In experiments, shock waves were generated by a research electrohydraulic lithotripter modeled after the Dornier HM-3, and stones were made from U-30 cement. Cylindrical stones of various length to diameter ratios, stones of conical shape, and stones with artificial cracks were studied. In other cases, baffles to block specific waves that contribute to spallation or squeezing were used, and glycerol was used to suppress cavitation. The theory was based on the elasticity equations for an isotropic medium. The equations were written in finite differences and integrated numerically. Maximum compression, tensile and shear stresses were predicted depending on the stone shape and side-surface condition in order to investigate the importance of the stone geometry. It is shown that the theoretical model used explains the observed position of a crack in a stone. The theory also predicts the efficiency of stone fragmentation depending on its shape and size, as well as on the presence of cracks on the stone surface and baffles near the stone.


System and Methods for Tracking Finger and Hand Movement Using Ultrasound

Record of Invention Number: 47931

John Kucewicz, Brian MacConaghy, Caren Marzban


10 Jan 2017

Novel Probe and Workflow for Ultrasonic Propulsion

Record of Invention Number: 47322

Mike Bailey, Bryan Cunitz, Brian Dickinson, Barbrina Dunmire, Brian MacConaghy, Adam Maxwell


1 May 2015

Ultrasound Instrumentation for Ureteroscopic and Transcutaneous Kidney Stone Removal

Record of Invention Number: 46839

Thomas Lendvay, Mike Bailey, Ryan Hsi, Brian MacConaghy, Adam Maxwell


4 Feb 2014

More Inventions

Method for Testing Output Force of an Ultrasonic Propulsion Device

Record of Invention Number: 46441

Bryan Cunitz, Mike Bailey, Brian MacConaghy


12 Mar 2013

Disposable Ultrasound Guided Catheter

Record of Invention Number: 46135

Revathi Murthy, Samuel Browd, Brian MacConaghy, Pierre Mourad


22 Jun 2012


The invention disclosure describes the placement of an acoustic element in the mechanical tip of a catheter that is to be used by neurosurgeons to break up and remove blood clots in cases of hemorrhagic stroke.

Record of Invention Number: 46057

Brian MacConaghy


24 Apr 2012

Surgical Guide for AIDS Prevention

Record of Invention Number: 46050

Brian MacConaghy, Mike Bailey


18 Apr 2012

Using Vibrating Polyvinylidene Difluoride (PVDF) as a Support for Reverse Osmosis Membranes

Record of Invention Number: 45917

Jaffer Alali, Brian MacConaghy, Pierre Mourad


15 Jan 2012

Reducing the Cost of Water Desalination

Record of Invention Number: 45905

Jaffer Alali, Brian MacConaghy, Pierre Mourad


15 Oct 2011

Acoustics Air-Sea Interaction & Remote Sensing Center for Environmental & Information Systems Center for Industrial & Medical Ultrasound Electronic & Photonic Systems Ocean Engineering Ocean Physics Polar Science Center