Optical, Optoacoustic, and Ultrasound Techniques for Noninvasive Diagnostics

and Therapy

Rinat O. Esenaliev, Ph.D.Professor,

Director of Laboratory for Optical Sensing and Monitoring,Director of High-resolution Ultrasound Imaging Core,

Center for Biomedical Engineering,UTMB Cancer Center,

Department of Neuroscience and Cell Biology, and Department of Anesthesiology,

University of Texas Medical Branch, Galveston, TX E-mail: riesenal@utmb.edu

• Optoacoustic Platform for Noninvasive Sensing, Monitoring and Imaging: absorption contrast

• Noninvasive Monitoring with Optical Coherence Tomography (OCT): scattering contrast

• Nanoparticles and Radiation (Optical, Ultrasound) for Cancer Therapy or for Drug Delivery: Including laser + gold nanoparticle (nanoshells, nanorods, etc.) for cancer therapy

Our Group Has Pioneered Noninvasive Therapeutic and Diagnostic Technologies:

• 40 peer-reviewed papers

• 15 patents including 7 issued patents

• $9.3M in 23 research grants from NIH, DOD, state and private funding agencies

Publications, Patents, Grants

Research Team

Visiting Scientists: Valeriy G. Andreev, Ph.D., Physics Department, Moscow State University

Alexander I. Kholodnykh, Ph.D., Physics Department Moscow State University

Research Associates, Post-Doctoral Fellows, and Graduate and Undergraduate Students:

Christian Bartels, M.S.; Saskia Beetz, B.S.; Peter Brecht, Ph.D.;Olga Chumakova, Ph.D., Inga Cicenaite, M.D.; Olaf Hartrumpf, B.S.; Dominique Hilbert, B.S.;

Manfred Klasing, B.S.; Anton Liopo, Ph.D., Roman Kuranov, Ph.D.; Kirill V. Larin, Ph.D.; Irina V. Larina, Ph.D.; Margaret A. Parsley, B.S.; Igor Patrikeev, Ph.D.;

Andrey Y. Petrov, B.S.; Yuriy E. Petrov, Ph.D.; Irina Y. Petrova, Ph.D.; Emanuel Sarchen, B.S.;Veronika Sapozhnikova, Ph.D.; Alexandra A. Vassilieva, M.D.; Karon E. Wynne, B.S.

Collaborators:Donald S. Prough, M.D., Department of Anesthesiology, UTMB

Michael Kinsky, M.D., Department of Anesthesiology, UTMBClaudia Robertson, M.D, Baylor College of Medicine, Houston

Luciano Ponce, M.D., Baylor College of Medicine, HoustonJoan Richardson, M.D., Department of Pediatrics, UTMB

B. Mark Evers, M.D., Department of Surgery, UTMBDonald E. Deyo, D.V.M., Department of Anesthesiology, UTMB

Douglas S. Dewitt, Ph.D., Department of Anesthesiology, UTMB

Optoacoustic Grants

NIH R01 # EB00763 “Novel Sensor for Blood Oxygenation”.

NIH R21 # NS40531 “Optoacoustic Monitoring of Cerebral Blood Oxygenation”.

NIH R01 # NS044345 “Optoacoustic Monitoring of Cerebral Blood Oxygenation”.

John Sealy Memorial Endowment Fund for Biomedical Research. Grant: “Noninvasive Monitoring with Novel, High-resolution Optical Techniques”.

Moody Center for Traumatic Brain & Spinal Cord Injury Research.

Seed Grant: “Noninvasive Optoacoustic Hemoglobin Monitor” – Subaward from Noninvasix, Inc.

Texas Emerging Technology Fund (TETF): “Noninvasive Platform for Blood Diagnostics” – Subaward from Noninvasix, Inc.

NIH STTR: “Noninvasive Optoacoustic Monitoring of Circulatory Shock”.

DOD: "Noninvasive Monitoring of Cerebral Venous Saturation in Patients with Traumatic Brain Injury“.

DOD: “Noninvasive Circulatory Shock Monitoring with Optoacoustic Technique”.

Noninvasix, Inc.

• UTMB Incubator Startup

• Exclusive, world-wide license on optoacoustic monitoring, sensing, and imaging in humans and animals in vivo and in vitro (non-cancerous appl.)

• Licensed key US and International patents including patents on monitoring OxyHb, THb, ICG, etc. in blood vessels and in tissues

• FD: UTMB and Drs. Esenaliev and Prough are co-owners of Noninvasix

Optoacoustics for Biomedical Imaging, Monitoring, and Sensing - 1

Early 1990s: First Peer-reviewed Papers on Biomedical Optoacoustics

Institute of Spectroscopy, Russian Academy of Sciences:

R.O. Esenaliev, A.A.Oraevsky, V.S.Letokhovand

A.A. Karabutov (Moscow State University)

Optoacoustics for Biomedical Imaging, Monitoring, and Sensing - 2

Since Mid 1990s we continued the biomedical optoacoustic works in the USA: Mid 1990s: Optoacoustic Signals from Deep Tissues (Depth: 5 cm)

Late 1990s: First Optoacoustic Images

Mid 1990s - Present: Optoacoustic Imaging, Monitoring and Sensing Patents: imaging, monitoring of temperature, coagulation, freezing, oxygenation, hemoglobin, other important physiologic parameters, etc.

Optoacoustics for Biomedical Imaging, Monitoring, and Sensing - 3

2001: We Obtained First High-resolution Optoacoustic Images

Photonics West/ BIOS/SPIE Statistics: At present, Biomedical Optoacoustics is the fastest growing and

largest area in biomedical optics

• Traumatic brain and spinal cord injuries are the leading cause of deathand disability for individuals under 50 years of age (car accidents, falls, etc.)150,000 patients/year with moderate or severe traumatic brain injury and 2 million/year with total TBI (mild, moderate, severe).

• Continuous and accurate monitoring of cerebral venous blood oxygenation is critically important for successful treatment of these groups of patients

• Clinical data indicate that low cerebral venous blood oxygenation (below 50%) results in worse outcome (death or severe disability); 55-75% is normal (venous!)

MOTIVATION - 1

Cerebral Venous Oxygenation Monitoring: for Patients with Traumatic Brain Injury (TBI)

and Cardiac Surgery Patients

• Existing methods are invasive (catheters in jugular bulb), and noninvasive (NIRS) cannot measure cerebral venous oxygenation

• Circulatory shock is common in critically ill patients

• Continuous and accurate monitoring of central venous blood oxygenation is critically important for successful treatment of these patients: reduction in mortality from 46.5% to 30%

• Clinical data indicate that low central venous blood oxygenation (below 70%) results in worse outcome (death or severe complications); 70% is normal

MOTIVATION - 2Central Venous Oxygenation Monitoring:

for Patients with Circulatory Shock

• Existing methods are invasive (pulmonary artery catheters), while noninvasive (NIRS) cannot measure central venous oxygenation

MOTIVATION - 3

THb MonitoringTotal hemoglobin concentration ([THb]) measurement/monitoring is important clinical test during:

Routine health assessment (reveals anemia - [THb] < 11 g/dL or polycythemia [THb] > 18 g/dL )2 billion people suffer from anemia worldwide

Surgical procedures involving rapid blood loss, fluid infusion, or blood transfusion

Existing methods are invasive:

Blood sampling Optical monitoring in an extracorporeal blood circuit Noninvasive methods are inaccurate:Pressing need for noninvasive methods for continuous, accurate [THb]

measurement

Pure Optical Techniques (NIRS) Cannot Detect Signals Directly from Blood Vessels

Due to Strong Light Scattering in Tissues

Optoacoustic Technology:Optical Contrast + Ultrasound Resolution

1. Light pulses into blood in a vessel

2. Blood hemoglobin absorbs light & emits ultrasound in proportion to concentration in the vessel (due to thermal expansion)

3. Ultrasound wave travels without scattering and arrives at specific time proportional to blood vessel depth

4. Sensor detects ultrasound

5. Software determines location, size, and oxygenation of blood in the vessel

Optical Input

Acoustic Output

Principle of Laser Optoacoustic Monitoring and Imaging

Laser Optoacoustic Monitoring and Imaging Is Based on Generation, Detection, and Analysis

of Thermoelastic Pressure Waves Induced by Short Laser Pulses

– laser-induced temperature rise; µa – absorption coefficient;

F– fluence of the laser pulse; –density;

cv – heat capacity at constant volume

Thermoelastic (Optoacoustic) Pressure, P:

aclaser

High Resolution and Contrast Can Be Achieved Only when Short Laser Pulses Are Used(The Condition of Stress Confinement)

L – desirable spatial resolution ac– time of propagation of acoustic wave

through the distance = L ac = L/ cs

where cs = 1.5 m/ns – speed of sound in tissue

where laser– laser pulse duration

The Condition of Stress Confinement:

[1/oC] – thermal expansion coefficient; cs [cm/s] – speed of sound;

Cp [J/goC] – heat capacity at constant pressure; F(z) [J/cm2] – fluence of the optical pulse;

µa [cm-1] – absorption coefficient of the medium; –Grüneisen parameter (dimensionless) zcst

Spatial Distribution of Optoacoustic Pressurein an Absorbing Medium without Scattering:

Temporal Profile of Optoacoustic Waves in the Medium:Since:

Generation of Optoacoustic Wave in Absorbing Medium

2/1)]}1([3{ gsaaeff

Generation of Optoacoustic Wave in Tissue

Spatial Distribution of Optoacoustic Pressurein a Tissue (not close to the surface):

k–coefficient depending on tissue optical propertiesµeff – tissue attenuation coefficient

Temporal Profile of Optoacoustic Waves in the Tissue:

Advantages of Optoacoustic Technique

1. High Contrast (as in Optical Tomography) because

It Utilizes Optical Contrast

2. High Resolution (as in Ultrasonography) due to

Ultrasound Wave Detection

(Insignificant Scattering of Ultrasonic Waves

Compared with Light Wave Scattering in Tissues)

1.00

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400 600 800 1000 1200

Wavelength (nm)

Abs

orpt

ion

Coe

ffici

ent a

(1/c

m)

Oxyhemoglobin (HbO2)

Hemoglobin (Hb)

Absorption Spectra of Oxy- and Deoxyhemoglobin

Steven L. Jacques, Scott A. PrahlOregon Graduate Institute

Steven L. Jacques, Scott A. PrahlOregon Graduate Institute

Therapeutic Window: 600 – 1400 nm

Low absorption and low scattering = Deep penetration

Our Goal Is to Develop Optoacoustic Devicefor Monitoring:

Oxygenation Cerebral Central Venous Peripheral Venous Arterial

Total Hb Concentration Pathologic Hemoglobins

Carboxyhemoglobin Methemoglobin

Dye Concentration (ICG) Blood Volume Cardiac Output Hepatic Function

Noninvasive Venous Pressure Noninvasive Arterial Pressure

Optoacoustic Monitoring Systems Used in these Studies:

OPO-Based Optoacoustic Monitoring Systems and

Laser Diode-Based, Optoacoustic Monitoring Systems

Wavelengths: 680 – 2400 nm; Duration: 10 - 150 ns

Optoacoustic Probes Used in these Studies:

Single-element Probes,Focused Probes,

Optoacoustic Arrays

Specially developed sensitive, wide-band ultrasound detectors: 25kHz – 10 MHz

Ultrasound Imaging Systems Used in these Studies:

Standard Clinical GE Systems

andSiteRite Systems

High-Resolution Vevo System

• High Resolution: 30 microns at depth of up to 25 mm• Real-time• Longitudinal Studies• Measure Physiological parameters• Contrast/Molecular Imaging• Translatable to man

Novel, High-resolution Ultrasound Imaging System(Vevo, VisualSonics)

Schell RM et al., Anesth Analg 2000;90:559.

Gopinath SP, Robertson CS, Contant CF, et al. Jugular venous desaturation and outcome after head injury. J. Neurol. Neurosurg. Psychiatry. 57:717-23, 1994.

Outcome after Head Injury Closely Correlateswith Cerebral Venous Oxygenation / OxyHb Saturation

Below 50%:death or

severe disability

Noninvasive, optoacoustic monitoring of cerebral venous blood oxygenation

Superior Sagittal Sinus (SSS)

Optoacoustic Probe

65%Time (min) SS

S SO 2

Noninvasive, Optoacoustic Cerebral Venous Blood Oxygenation Monitoring in Sheep

1064 nm 700 nm

Optoacoustic Spectra from Human SSS and Hemoglobin Absorption Spectra

Ultrasound Imaging and CorrespondingOptoacoustic Signals from Central Veins

Optoacoustic Spectra from Carotid Artery and Central Vein

Carotid Artery Central Vein

700 800 900 1000 11000

1

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Abs

orpt

ion

Coe

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ent (

arb.

un.

)

Wavelength (nm)

HbO2

Hb 10% 20% 30% 40% 50% 60% 70% 80% 90%

Continuous, Real-time Measurement of Central Venous Oxygenation Using Optoacoustic Monitoring System

(Stable Subject)

0 10 20 300

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SO2, %

Cen

tral V

enou

s B

lood

Oxy

gena

tion

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Time (min)

<SO2> = 75.1 +/- 1.1 %

High-Resolution Ultrasound Imaging and CorrespondingOptoacoustic Signals from Peripheral Veins

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0 2 4 6

Opt

oaco

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Time (s)

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Optoacoustic Spectra from Peripheral Vein and Radial Artery and Hemoglobin Absorption Spectra

Peripheral Vein Radial Artery

Optoacoustic Signals from Bloodin Radial Artery Phantom

2 3 4

-0.1

0.0

0.1

0.2

Opt

oaco

ustic

Sig

nal (

V)

Time (s)

4.7 g/dL 8.6 g/dL 11.9 g/dL 15.8 g/dL

Optoacoustic signal from sheep blood at different concentrations of THb (gradual dilution of blood) and its amplitude

0 5 10 15 200.00

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0.25 R2 = 0.997

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plitu

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f the

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Total Hemoglobin Concentration (g/dL)

Conclusions

• The optoacoustics is a platform monitoring and imaging technology with high (optical) contrast and high (ultrasound) resolution in tissues

• The sensitive, wide-band optoacoustic probes provide sufficient lateral and axial resolution for measurements in large and small blood vessels

• The optoacoustic monitoring systems may provide clinically acceptable accuracy of cerebral, central, and peripheral venous oxygenation measurements

• The optoacoustic monitoring systems may provide high accuracy of hemoglobin measurements

Nanoparticles and Radiationfor Cancer Therapy or

for Drug Delivery

Overview of TechnologyChemotherapy, surgery, radiation therapy have limitations

and are not capable of safe and efficient therapy of solid tumors.This technology offers efficient cancer therapy with no or minimal side effects.The technology is based on interaction of light, microwaves, radiowaves, or ultrasound with nanoparticles.

Radiation + Nanoparticles

Nanoparticle-mediated Therapy Drug Delivery

Ligh

t-Ind

uced

The

rapy

MW

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uced

The

rapy

RW

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uced

The

rapy

US-

Indu

ced

Ther

apy

Ligh

t-Enh

ance

d D

D

MW

-Enh

ance

d D

D

RW

-Enh

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d D

D

US-

Enha

nced

DD

Drug Delivery ProblemApproximately 1.4 million new cases are diagnosed and more than 500,000 deaths occur as a result of cancer every year in the United States.  

Many promising therapeutic agents have been proposed for cancer therapy for the past two decades. Their potential is proven in numerous preclinical studies.

However, limited success has been achieved in tumor therapy.

Modified from R.Jain, “Barriers to drug delivery in solid tumors”, Scientific American, 1994.

Barriers to drug delivery: 

• blood vessel wall• interstitial space• cancer cell membrane  Penetration is especially poor for macromolecular therapeutic agents:  

• monoclonal antibodies 150 – 300 kDa• cytokines 6 – 70 kDa• antisense oligonucleotides 5 – 10 kDa• gene-targeting vectors > 1,000 kDa

The nanoparticles can be selectively accumulated in tumors by:• “passive” delivery due to increased leakage of tumor capillaries (EPR effect)• “active” delivery with the use of antibodies, short peptides, etc. 

Interaction of particles with radiation produce cavitation and other effects 

Which RESULTS IN:

• rupture or changes in tumor blood vessel wall and cancer cell membrane • microconvection in the interstitium 

INTERACTION of NANOPARTICLES with ULTRASOUND CAN ALTER the BARRIERS to DRUG DELIVERY

Advantages of PLGA nanoparticles:•can accumulate in tumors (EPR effect)•biodegradability, •biocompatibility,•may provide stable cavitation,•PLGA approved for clinical use by FDA (surgical sutures, etc.)

Biodegradable and biocompatible polymer Poly (D,L-lactide-co-glycolic acid) 50:50, PLGA

The nanoparticles was prepared by double water/oil/water emulsion solvent evaporation technique followed by filtration with 220-nm Millex filters

PLGA Nanoparticles

SEM Optical Microscopy

High Performance Particle Sizer HPPS 5001 Zetasizer Nano

PLGA nanoparticles (0.5% solution)

Definity (0.2% solution)

EXPERIMENTAL SETUP FOR STUDIES IN VIVO

In Vivo Gene DeliveryControl Tumor Irradiated Tumor

Precise Damage Induced by Ultrasound+Nanoparticles Deeply in Tissues

(whole tumor)

(Necrotic region)

Reference subtractedWash in curve whole tumor area

Reference subtractedWash in curve Necrotic region

Reference subtracted Contrast Images

Wash in curve for nanoparticles circulating in tumor

Reference subtracted Contrast Image

1. John Sealy Memorial Endowment Fund

2. Texas Advanced Technology Program (grant #004952-0088-2001)

3. Department of Defense Breast Cancer Research Program (grant #DAMD17-01-1-0416)

4. National Institutes of Health (grant #RO1 CA104748)

5. Department of Defense Prostate Cancer Research Program (grant #W81XWH-04-1-0247)

Acknowledgement