Dr. Mourad

Research Labs:
Mourad Lab

• Research Overview
• Investigators/ Researchers
• Current Research
• Research Questions
• Research Highlights
• Research Methods
• Bibliography of Selected Publications

Research Overview

Pierre Mourad, PhD is an Associate Professor of Neurological Surgery and a Principal Physicist in the Applied Physics Laboratory. His research interests are in the application of ultrasound to diagnosis and treatment of CNS disease, including blood-brain barrier disruption for drug delivery, acceleration of recovery of peripheral nerve injuries, noninvasive determination of intracranial pressure and localization of pain generators.

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Investigators /Researchers

• Pierre D. Mourad, PhD

Current Research

1. Use of ultrasound to non-invasively measure intracranial pressure and cerebral perfusion pressure; automation of transcranial Doppler.

Hypothesis: We can combine automatic localization and lock on to the middle cerebral artery with transcranial Doppler imaging and arterial blood pressure data into predictive algorithms for critical neurological medical variables that currently require a neurosurgical procedure to implement.
Status: Pre-clinical studies recently completed at Harborview Medical Center in Seattle, University of Pennsylvania, Columbia University, The Barrow Neurological Institute, and Wilford Hall Air Force Hospital; complementary in vitro and animal studies on-going at the University of Washington; various papers and patents completed as well as under construction.
Personnel: Kliot M and Chesnut R (Neurosurgery), and PhysioSonics, Inc.


2. Use of ultrasound to differentially diagnose sources of pain.

Hypothesis: Intense focused ultrasound under image guidance can map the distribution of sensations in a patient in pain to localize painful tissue pathology.
Status: Prototype built and calibrated; animal studies on-going and associated papers and patents written or under construction; human sensory trials finished and associated paper under construction.
Personnel: Jarvik GA (Radiology), Kliot M, Loeser J (Neurosurgery), Gofeld M, Richebee P, Terman G (Anesthesiology).

3. A novel device for early dental caries (e.g., ‘cavities’) detection.

Hypothesis: Near-infrared spectroscopy images of pre-caries lesions on sentinel teeth can yield a prediction of the likelihood that a given child will develop cavities in the near future.
Status: Bench-top feasibility studies on going. Personnel: Berg J (Pediatric Dentistry) and Seibel E (Mechanical Engineering).

4. Application of terahertz radiation for grading & diagnosis of burns.

Hypothesis: Create images of burns with terahertz radiation to determine the viability of stem cell niches within damaged skin as well as extent of desiccation.
Status: Feasibility studies using a rat model of burns completed; papers and a patent application under construction.
Personnel: With Winebrenner DP and Chen A of APL.

5. Imaging endogenous and exogenous brain-tissue displacement patterns for the case of traumatic brain injury.

Hypothesis: Hemorrhage, edema, diffuse axonal injury each have different ranges of shear modulus compared to normal brain tissue. Such differences can form the basis of brain imaging with a field-deployable ultrasound device.
Status: Early-stage animal based research; have acquired sufficient human data collected to write up as a pilot study.
Personnel: Murphy S, Morison R (Neurological Surgery), Stone J (University of Virginia).

6. Opening the blood-brain barrier with ultrasound.

Hypothesis: Ultrasound disruption of the blood-brain barrier can deliver drugs into the brain in a focal and safe manner.
Status: Writing up paper showing the ability of ultrasound to enhance the flux of drugs in addition to dyes into the brain. Moving to study of enhancement of antibody-complected drug flux into brain, via catheters.
Personnel: With Silbergeld DL and Levitt M (Neurosurgery).

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Research Questions

Broadly speaking, Dr. Mourad performs applied and basic research involving physics, especially ultrasound and, emergently, electromagnetic radiation, focused primarily on applications to the diagnosis and treatment of diseases and disorders of the central and peripheral nervous systems. Dr. Mourad's work is always motivated by clinical problems.

Research Highlights

• Ability to predict cerebral perfusion pressure, as shown on humans.
• Automated transcranial Doppler into commercialization.
• Developing maps of brain-tissue stiffness, in vivo.
• Developing a non-invasive evocative test to aid the in the localization and diagnosis of pain, also on its way to commercialization.
• Demonstration of drug flux into brain facilitated by ultrasound.

Research Methods

• Experimental (in vitro, ex vivo, in vivo, and human based studies) methods supporting medical applications of physics (primarily ultrasound, also including THz radiation, near-infrared spectroscopy).
• Biological effects due to therapeutic ultrasound.
• Translational research as a field of study and its concrete practice, including generation of companies and intellectual property.

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Bibliography of Selected Publications

1. Roberts F, Hacker BM, Oswald T, Mourad PD, McInnes JC. (2010) Evaluation of the use of ultrasound within a power toothbrush to dislodge oral bacteria using an in vitro Streptococcus mutans biofilm model. The American Journal of Dentistry. V23(2):65-69.
2. Mourad PD, Roberts FA, McInnis JC (2007) Synergistic use of ultrasound and sonic motion for removal of dental plaque bacteria. Compendium of Continuing Education in Dentistry. V28(7):296-301.
3. Miao CH, Brayman AA, Loeb KR, Ye P, Zhou L, Mourad PD, Crum LA (2005) Ultrasound Enhances Gene Delivery of Human Factor IX Plasmid. Human Gene Therapy July, V16:893-905 (e-available June 05).
4. Porter TM, Murthy N, Mourad PD, Stayton PS, Hoffman AS, Crum LA (2005) Control of cavitation-induced hemolysis with a surface-active polymer. Acoustic Research Letters Online. 6:201-206
5. Mourad PD, Silbergeld DL (2005) Breaking the blood-brain barrier: using high-intensity focused ultrasound to treat malignant brain tumors. RT-Image. V18(32):28-32.
6. Mourad PD, Farrell L, Stamps L, Chicione M, and Silbergeld DL. (2005) Why are systemic glioblastoma multiforme rare: systemic and cerebral growth of a mouse glioblastoma. Surgical Neurology, V63(6), 511-519.
7. Mourad, PD, L. Farrell, P. Santiago, H. L. Fillmore, W. C. Broaddus, and D. L. Silbergeld. (2003) Quantitative Assessment of Glioblastoma Invasion in vivo. Cancer Letters. Mar 20;192(1):97-107
8. Winstead, N. S., Sikora, T. D., Thompson, D. R. and Mourad PD(2002) Direct influence of gravity waves on surface-layer stress during a cold-air outbreak, as shown by synthetic aperture radar. Mon. Wea. Rev. 130, 2764-2776.
9. Mesiwala, A. H. and Mourad PD (2002) Monitoring of biologic effects of focused ultrasound beams on the brain. Radiology. Jul;224(1):294-6; discussion 296-7.
10. Mesiwala, A. H. , L. Farrell, H. J. Wenzel, L. A. Crum, D. L. Silbergeld, H. R. Winn, and Mourad PD. (2002) High Intensity Focused Ultrasound Selectively Disrupts the Blood-Brain Barrier in vivo. Ultrasound in Medicine and Biology. 28(1) 389-400.
11. Poliachik, S. L., W. L. Chandler, Mourad PD, R. J. Ollos and L. A. Crum (2001) Activation, aggregation and adhesion of platelets exposed to high intensity focused ultrasound Ultrasound in Medicine and Biology 27(11) 1567-1576.
12. Kwok, C. S., Mourad PD, L. A. Crum, B. D. Ratner (2001) Self-assembled Molecular Structures as Ultrasonically-responsive Barrier Membranes for Pulsatile Drug Delivery. J. Biomed. Mat. Res.57(2) 151-164.
13. Winstead, N. S., R. Schaff, and Mourad PD (2001) Synthetic Aperture Radar Observations of Surface Signatures of Cold-Season Bands over the Great Lakes. Weather and Forecasting. 16 315-328.
14. Mourad PD, N. Murthy, T. Porter, S. L. Poliachik, L. A. Crum, and A. S. Hoffman and P. S. Stayton, Ultrasound and Poly(2-ethylacrylic) acid act synergistically to permeabilize lipid bilayers (2001) Macromolecules. 34, 2400-2401.
15. Mourad PD, D. Lazar, F. P. Curra, A. M. Avellino, B. C. Mohr, L. D. McNutt, K. C. Andrus, L. A. Crum, M. Kliot (2001) Ultrasound accelerates functional recovery after peripheral nerve damage. Neurosurgery. 48(5), 1136-1141.
16. Vandemark, D., Mourad PD, T. Crawford, C. Vogel, J. Sun, S. A. Bailey and B. Chapron (2001) Measured changes in ocean surface roughness due to atmospheric boundary layer rolls. J. Geophys. Res. 106(C3), 4639-4654.
17. Chang, P. P., W.-S. Chen, Mourad PD, S. L. Poliachik and L. A. Crum (2001) Thresholds for inertial cavitation in Albunex suspensions under pulsed ultrasound conditions. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control 48(1), 161-170.
18. Moller, D., Mourad PD, and S. Frasier (2001) Field observations of radar backscatter from the ocean surface under low wind speed conditions. J. Geophys. Res. 105(C10), 24,059-24,069.
19. Winstead, N. S. and Mourad PD (2000) Great Lake-scale atmospheric thermal circulation imaged with Synthetic Aperture Radar. Mon. Wea. Rev. 128, 3654-3663.
20. Curra, F. P., Mourad PD, V. A. Khokhlova, R. O. Cleveland and L. A. Crum (2000) Numerical simulations of heating patterns and tissue temperature response due to high intensity focused ultrasound fields. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 47(4), 1077-1088.
21. Kwok, C. S., Mourad PD, L. A. Crum, and B. D. Ratner (2000), Surface modification of polymers with self-assembled molecular structures: multitechnique surface characterization. Biomacromolecules, 1(1), 139-148.
22. Kristovich, D.A.R., G.S. Young, J. Verlinde, P.J. Sousounis, Mourad PD, D. Lenschow, R.M. Rauber, M.K. Ramamurthy, B.F. Jewett, K. Beard, E. Cutrim, P.J. DeMott, E.W. Eloranta, M.R. Hjelmfelt, S.M. Kreidenweis, J. Martin, J. Moore, H.T. Ochs, D.C. Rogers, J. Scala, G. Tripoli, and J. Young (2000), The Lake-Induced Convection Experiment (Lake-ICE) and the Snowband Dynamics Project. Bull. Am. Meteor. Soc., 81(3), 519-542.
23. Mourad PD, D. Thompson and D. Vandemark (2000) Extracting fine-scale wind fields from synthetic aperture radar of the ocean surface. Johns Hopkins APL Technical Digest, V21(1):7-14.
24. Poliachik, S., W. Chandler, Mourad PD, M. Bailey, S. Bloch, R. Cleveland, P. Kaczkowski, G. Keilman, T. Porter and L. A. Crum (1999) Effect of high-intensity focused ultrasound on whole blood with and without microbubble contrast agents. Ultrasound in Med. and Bio, 25(6) 991-999.

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