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Measurement of Blood Flow in Bone by Laser Doppler Imaging

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Measurement of Blood Flow in Bone by Laser Doppler Imaging University of Calgary PRISM: University of Calgary's Digital Repository Graduate Studies Legacy Theses 2000 Measurement of blood flow in bone by laser doppler imaging Shymkiw, Roxane Chia-Chi Shymkiw, R. C. (2000). Measurement of blood flow in bone by laser doppler imaging (Unpublished master's thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/17412 http://hdl.handle.net/1880/40506 master thesis University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. Downloaded from PRISM: https://prism.ucalgary.ca THE UNIVERSITY OF CALGARY Measurement of Blood Flow in Bone by Laser Doppler Imaging by Roxane Chia-Chi Shymkiw .A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE BIOMEDICAL ENGWEERING DEPARTMENT OF MECHANICAL AND MANUFACTURING ENGJNEERlNG CALGARY, ALBERTA MAY, 2000 O Roxane Chia-Chi S hymkiw 2000 National Library Bibliotheque nationale (*Iof Canada du Canada Acquisitions and Acquisitions et Bibliographic Services services bibliographiques 395 Wellington Street 395, rue Wellington OttawaON K1AON4 Ottawa ON K1A ON4 Canada Canada Your file Vorre reference Our fi& Norre reterence The author has granted a non- L'auteur a accorde une licence non exclusive licence allowing the exclusive pennettant a la National Library of Canada to Bibliotheque nationale du Canada de reproduce, loan, distribute or sell reproduire, preter, distribuer ou copies of thls thesis in microform. vendre des copies de cette these sous paper or electronic formats. la forme de microfiche/filrn, de reproduction sur papier ou sur format electronique. The author retains ownership of the L'auteur conserve la propriete du copyright in this thesis. Neither the droit d'auteur qui protege cette these. thesis nor substantial extracts &om it Ni la these ni des extraits substantiels may be printed or otherwise de celle-ci ne doivent Ctre imprimes reproduced without the author's ou autrement reproduits sans son permission. autorisation. ABSTRACT Although the mechanisms are not clearly explained. blood flow may play an important role in mediating skeletal adaptation. Most techniques currently available to measure blood flow in bone are time-consuming and require destruction of the tissue whereas laser Doppler technology offers a less invasive method. The current series of studies investigated the effectiveness of laser Doppler perfusion imaging (LDI) for measuring perksion in cortical bone. Preliminary pilot studies were conducted to determine the feasibility of using LDI on bone, as well as assessment of bone optical properties and flow characteristics. Results indicated that LDI effectively measured blood flow in cortical bone and detected physiologically induced changes in perfusion. A significant positive correlation was found between rnicrosphere-determined flow and LDL output (r = 0.58. p < 0.05). Repeatability of consecutive LDI perfusion measurements was within 5%. Red and near infrared wavelengths were significantly correlated suggesting the two wavelengths measured pefision in the same region. Red and near infrared lasers were measuring blood flow up to 0.8 mm and 0.9 mm. respectively, into the tissue. This study characterized LDt for measuring perhsion in bone and correlated tlow measured by LD t to standardized microsphere-determined flow. The ability to profile heterogeneous structure and sequential changes in blood flow in bone suggests this method has the potential for investigating the role of blood flow in bone metabolism. healing, and remodeling. To my dad, whose footsteps I've always wanted to follow and to my best friend. and husband. Dave My many thanks to: All that assisted in completion of this work: Catherine Leonard, Brett McGuinness, Craig Sutherland, and Greg Wohl Kevin Forrester, for his overwhelming contribution of time and knowledge Ron Zernicke, for his guidance and opening the door to many opportunities over the past Years Those who gave me strength through their friendship: Barb Kralovic, Christine Maurette, Tasha Reid (Itett), Maggie Erickson. Connie Sullivan, Chantelle Carley, Todd Leask, Carla Sciarretta, Gail Thornton, Shawna Yanke, Leonard Pianalto, Greg Wohl, Greg Kawchuk, and Brett McGuinness And most of all, to my parents and family (Jocelyn, Andrew, Charlie, Alma, and Frank) for their understanding, encouragement and support. TABLE OF CONTENTS .. Approval Page .................................................................................... .II ... Abstract ....................................................................................... .III Dedication and Acknowledgments .......................................................... iv Table of Contents .............................................................................. v . List of Figures .................................................................................... .vti List of Tables .................... .. ................................................................. .x List of Abbreviations .............................................................................. si CHAPTER I INTRODUCTION ...................................................... 1 CHAPTER 2 BACKGROUND .................................................. .-I Anatomy, Physiology and Pathology of Blood Flow in Bone ......-+ Laser Doppler Principle .......................................... 16 2.2.1 Laser Speckle Imaging .................................. IS 2.2.7 Laser Doppler Flowmetry ................................. 19 3.2.3 LaserDopplerPerfbsion Irnagins ........................$0 Tissue Optics .......................................................... .20 Current Measurement Techniques ................................ .35 Study Objectives. Rationale, and Scope ....................... .37 CHAPTER 3 MATERIALS AND METHODS .................................. .-I2 3 .O Laser Doppler Pefision Imaging Standard Protocol .............. .42 3.1 Laser Doppler PeAsion Imaging Pilot Studies. .................... -43 3.1.1 Rooster Model.. ................................................ -43 3.1.2 Rabbit Model ............................................... -44 3.2 Bone Optical Properties Study ................................. .-IS 3.2.1 Thin Section Transmission ................................ -45 3 2.2 Thick Section Transmission ................................ -47 3.3 Flow Model Study ............................................ A8 3 .3.1 Detectable Range of Flow ................................. 48 3.3.2 Specular Reflectance .......................................... 50 Laser Doppler Perfusion Imaging Study ........................ 51 3.4.1 Animal Preparation ......................................... -51 3.4.2 Laser Doppler Perfusion Imaging ........................ 52 -- 3 .4.3 Evaluation of Blood Flow ................................. 33 3.4.4 Blood Flow Determination ................................. 54 3 4.5 Statistical Methods .......................................... 56 RESULTS ............................................................ 57 Laser Doppler Pedbsion Imaging Pilot Studies ............... 57 4.1. I Rooster Model ..................................................57 4.1.2 Rabbit Model .............................................. -58 Bone Optical Properties Experiments ................................ I9 4.2.1 Thin Section Transmission ................................. 59 4 Thick Section Transmission ................................. 61 Flow Model Study ............................................. 61 4.31 Detectable Range of Flow ................................. 61 4.3.2 S pecular Reflectance .......................................... 62 Laser Doppler Pehsion Imaging Study .....................6-1 4.41 Repeatability ................................................... 67 4.4.2 Red versus Near Infrared Wavelength ............... 68 4.4.3 Comparison of Laser Doppler Pehsion Irnay ing and Coloured Microspheres ................................. 70 CHAPTER 5 DISCUSSION ...................................................... 73 CHAPTER 6 CONCLUSION .................................................. 94 6.1 Future Work ............................................................ 95 REFERENCES LIST OF FIGUWS Figure 2.1 Anatomy of long bone blood supply ............................................ 5 Figure 2.2 Blood supply of long bone ..................................................... -6 Figure 2.3 Experimental arrangement of laser speckle imaging . ............... 17 Figure 2.4 Experimental arrangement of laser Doppler flowmetry ................ IS Figure 2.5 Experimental arrangement of laser Doppler perfbsion imaging . 19 Figure 2.6 Interaction of laser light on tissue .......................................... -21 Figure 2.7 Laser-tissue interaction according to Snell's law ..................... --73 Figure 2.8 Mean free path of laser light in soft noncoloured tissue as a ......26 function of wavelength . Figure 29 Sequence of esperimental studies involved in the analysis of .....39 the utility of laser Doppler pehsion imaging in bone . Figure 3.1 Laser Doppler pefision imaging experimental setup . .............. .-I3 Figure 3.2 Apparatus for thin section transmission experiments . .............
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