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PHOTOACOUSTIC IMAGING TO DETECT TUMOR

PHOTOACOUSTIC IMAGING TO DETECT TUMOR. HAIFENG WANG SUBHASHINI PAKALAPATI VU TRAN Department of Electrical and Computer Engineering University of Massachusetts Lowell. OUTLINE. Introduction Brief Principle of Photoacoustic (PA) Different Techniques of PAI

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PHOTOACOUSTIC IMAGING TO DETECT TUMOR

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  1. PHOTOACOUSTIC IMAGING TO DETECT TUMOR HAIFENG WANG SUBHASHINI PAKALAPATI VU TRAN Department of Electrical and Computer Engineering University of Massachusetts Lowell

  2. OUTLINE • Introduction • Brief • Principle of Photoacoustic (PA) • Different Techniques of PAI • Comparison of Various Imaging Techniques • Advantages and Disadvantages • Conclusion • Reference

  3. Brief • Conversion of photons to acoustic waves due to absorption and localized thermal excitation. • Pulses of light is absorbed, energy will be radiated as heat. • Heat causes detectable sound waves due to pressure variation.

  4. 3D photoacoustic imaging of melanoma in vivo. The picture is from Optical Imaging Laboratory, Department of Biomedical Engineering, Washington University in St. Louis

  5. Introduction of Ultrasound Ultrasound applications: Ultrasound in optical fibers

  6. Principle of photoacoustic Energy absorption layer • The light energy is converted into thermal energy via energy absorption layer; • The thermal energy converts into mechanical wave because of thermal expansion; • An acoustic wave is generated. Laser excitation Acoustic signals Optical fiber

  7. Principle of photoacoustic by gold nanoparticle Energy absorption layer Laser excitation Acoustic signals Optical fiber Gold nanoparticle Sound pulse Laser pulse

  8. Experimental set up of photoacoustic molecular imaging The pictureSeunghan Ha, Andrew Carson, AshishAgarwal, Nicholas A. Kotov, and Kang Kim; Detection and monitoring of the multiple inflammatory responses by photoacoustic molecular imaging using selectively targeted gold nanorods

  9. A typical PAT/TAT system The picture is from OptoSonics, Inc and Fairway Medical Technologies, Inc.

  10. Tumor Detection Using Endogenous Contrast Xueding Wang, William W. Roberts, Paul L. Carson, David P. Wood and J. Brian Fowlkes, Photoacoustic tomography: a potential new tool for prostate cancer, 2010 :Vol. 1, No. 4 : Biomedical Optics Express 1117

  11. Using Exogenous Contrast • 3-D photoacoustic imaging • Evans Blue acted as a contrast agent. • Deep lying blood vessels in real tissue samples were imaged at depths of 5 mm and at 9 mm from the plane of detection. • The sensitivity of the technique was proven by photoacoustic detection of single red blood cells upon a glass plate. C.G.A Hoelen et.al,1998

  12. PAImaging Using Gold Nano Particles Qizhi Zhang et.al,2010

  13. Qizhi Zhang et.al.,2010

  14. COMPARISON OF DIFFERENT IMAGING TECHNIQUES:ULTRASOUND • Transducer emit ultrasound wave and get signals back from object. D= t.v • Scan volume to get image • Pros & cons: No side effects but low resolution

  15. COMPUTED TOMOGRAPHY • Use X-ray to collect data • Detector collects the sum of absorption factors in one direction • Using the computing algorithms, the absorption factor of each voxel will be calculated. • 3D image will be constructed based on these factors. • Pros & cons: 3D, high resolution but increase the risk of cancer in those exposed

  16. MRI • A powerful magnetic field is used to align the magnetization of Hydrogen atoms in the body • Radio frequency fields are used to alter the alignment of this magnetization • Nuclei to produce a rotating magnetic field detectable by the scanner • Pros and Cons: 3D, good contrast but make acoustic noise and may effect on some implants in patients

  17. POSITRON EMISSION TOMOGRAPHY • Positron-emitting radionuclide (tracer) is introduced into the body on a biologically active molecule • System detects pairs of gamma rays emitted indirectly by a tracer • Three-dimensional images of tracer concentration within the body are then constructed by computer analysis

  18. Photoacoustic Imaging • PAI: Combine advantages of optical (high contrast) and ultrasound (great imaging depth and high resolution): • high optical contrast images • microscale resolution • reasonable penetration depth

  19. ADVANTAGES DISADVANTAGES 1. Limited path length 2. Temperature dependence 3. Weak absorption at short wavelengths • Ability to detect deeply situated tumor and its vasculature • Monitors angiogenesis • High resolution • Compatible to Ultra Sound • High penetration depth • Non-ionizing/Non-radioactivity • Small size • Easy to clean and maintenance • No acoustic noise

  20. Conclusion • PAI has an edge over other imaging modalities. • Though it is in its infancy and there have as yet been no large clinical trials,many initial studies have demonstrated the possibilities for its application in the biomedical field. • Clearly, we should expect to see many exciting clinical applications of PA technologies in the nearfuture.

  21. References 1.Fass, L., Imaging and cancer: A review. Molecular oncology, 2008. 2(2): p. 115-152. 2. Hall, E.J. and D.J. Brenner, Cancer risks from diagnostic radiology. Br J Radiol, 2008. 81(965): p. 362-378. 3. De Santis, M., et al., Radiation effects on development. Birth Defects Res C Embryo Today, 2007. 81(3): p. 177-82. 4. Brenner, D., Should we be concerned about the rapid increase in CT usage? Reviews on environmental health, 2010. 25(1): p. 63-68. 5. Rapacholi, M.H., Essentials of Medical Ultrasound: A Practical Introduction to the Principles, Techniques and Biomedical Applications. 1982. 6. Khan, T.S., et al., 11C-metomidate PET imaging of adrenocortical cancer.Eur J Nucl Med Mol Imaging, 2003. 30(3): p. 403-10. 7. Minn, H., et al., Imaging of Adrenal Incidentalomas with PET Using 11C-Metomidate and 18F-FDG. J Nucl Med, 2004. 45(6): p. 972-979. 8. Young, H., et al., Measurement of clinical and subclinical tumour response using [18F]-fluorodeoxyglucose and positron emission tomography: review and 1999 EORTC recommendations. European Organization for Research and Treatment of Cancer (EORTC) PET Study Group. European journal of Cancer, 1999. 35(13): p. 1773-1782. 9. Amen, D.G. and B.D. Carmichael, High-Resolution Brain SPECT Imaging in ADHD. Annals of Clinical Psychiatry, 1997. 9(2): p. 81-86. 10. Amen, D.G., C. Hanks, and J. Prunella, Predicting positive and negative treatment responses to stimulants with brain SPECT imaging. J Psychoactive Drugs, 2008. 40(2): p. 131-8. 11. Bonte, F.J., et al., Tc-99m HMPAO SPECT in the differential diagnosis of the dementias with histopathologic confirmation.ClinNucl Med, 2006. 31(7): p. 376-8. 12. Massoud, T.F. and S.S. Gambhir, Molecular imaging in living subjects: seeing fundamental biological processes in a new light. Genes Dev, 2003. 17(5): p. 545-80. 13. Gibson, A.P., J.C. Hebden, and S.R. Arridge, Recent advances in diffuse optical imaging. Phys Med Biol, 2005. 50(4): p. R1-43. 14. Kovar, J.L., et al., A systematic approach to the development of fluorescent contrast agents for optical imaging of mouse cancer models. Anal Biochem, 2007. 367(1): p. 1-12. 15. Frangioni, J.V., New Technologies for Human Cancer Imaging. Journal of Clinical Oncology, 2008. 26(24): p. 4012-4021. 16. Zhang, H.F., et al., Functional photoacoustic microscopy for high-resolution and noninvasive in vivo imaging. Nat Biotechnol, 2006. 24(7): p. 848-51. 17. Siphanto, R.I., et al., Serial noninvasive photoacoustic imaging of neovascularization in tumor angiogenesis. Opt Express, 2005. 13(1): p. 89-95. 18. Emelianov, S.Y., et al., Synergy and Applications of Combined Ultrasound, Elasticity, and Photoacoustic Imaging. IEEE Ultrasonics Symposium (2006), 2006: p. 405-415. 19. Jose, J., et al., Imaging of tumor vasculature using Twentephotoacoustic systems. Journal of Biophotonics, 2009. 2(12): p. 701-717.

  22. THANK YOU

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