ENGINEERING AND MEDICINE BY Mark H. Bechtel, M.D

ENGINEERING AND ENGINEERING AND MEDICINEMEDICINE

BYBY

Mark H. Bechtel, M.D.Mark H. Bechtel, M.D.

My StoryMy Story

• No inclination into medicine originallyNo inclination into medicine originally

• Mother and wife are nurses, Wife also CRNAMother and wife are nurses, Wife also CRNA

• 11stst hand experience with hospitalization hand experience with hospitalization

• Wanted ChangeWanted Change

• Career CounselingCareer Counseling

• Decided on Medicine in 1993Decided on Medicine in 1993

• Prerequisites by 1994 and started Med Prerequisites by 1994 and started Med School.School.

IntroductionIntroduction

• Moscow High SchoolMoscow High School• BSEE, University of Idaho 1989BSEE, University of Idaho 1989• Internships at Varian and Chevron during EE training.Internships at Varian and Chevron during EE training.• Test Engineering at IBM, 1989-1991Test Engineering at IBM, 1989-1991• VLSI Design at AHA, 1991-1994VLSI Design at AHA, 1991-1994• MD at University of Washington 1994-1998MD at University of Washington 1994-1998• Internship in Spokane, Washington 1999Internship in Spokane, Washington 1999• Radiology Residency at University of Wisconsin, 1999-2003Radiology Residency at University of Wisconsin, 1999-2003• General Radiologist in Brainerd, MN 2003-2004General Radiologist in Brainerd, MN 2003-2004• Musculoskeletal Fellowship at Penn State Hershey, 2004Musculoskeletal Fellowship at Penn State Hershey, 2004• General Radiologist, MSK Specialist, Yankton, SD, 2005-General Radiologist, MSK Specialist, Yankton, SD, 2005-

20062006• General Radiologist, MSK Specialist, Moscow, ID, 2006-General Radiologist, MSK Specialist, Moscow, ID, 2006-

presentpresent

Main PointsMain Points

• Engineers as PhysiciansEngineers as Physicians

• Engineers as Information System Engineers as Information System ExpertsExperts

• Biomedical EngineeringBiomedical Engineering

• Electrical Design in MedicineElectrical Design in Medicine

Physician EngineersPhysician Engineers

• Engineering is an excellent base for Engineering is an excellent base for medicinemedicine

• High percentage of radiologists are High percentage of radiologists are engineersengineers

• Engineering teaches a method of Engineering teaches a method of thinking that is not taught in other thinking that is not taught in other undergrad degreesundergrad degrees

Medical SchoolMedical School

• 4 Years4 Years

• Easier conceptually than engineeringEasier conceptually than engineering

• More time than engineeringMore time than engineering– Engineering: if understand the concept then Engineering: if understand the concept then

studying is over.studying is over.– Medicine: Doesn’t matter if understand the Medicine: Doesn’t matter if understand the

concept. Human body is dynamic and the concept. Human body is dynamic and the patient is still sick. Learning is constant and patient is still sick. Learning is constant and there is no definite endpoint.there is no definite endpoint.

• Much more memorizationMuch more memorization

InternshipInternship

• Most Physicians have internshipsMost Physicians have internships

• One year general trainingOne year general training

• Interview and selection processInterview and selection process

ResidencyResidency

• Three to Six yearsThree to Six years– Radiology (4 years)Radiology (4 years)

FellowshipFellowship

• Further specializationFurther specialization

• 1-2 years for radiology1-2 years for radiology

• ……

Engineers as Information Engineers as Information System SpecialistSystem Specialist

• Radiology is highly Technology DependentRadiology is highly Technology Dependent

• PACS systemsPACS systems– Large storage systemLarge storage system– Single CT can have 2000 images at 500Kbyte Single CT can have 2000 images at 500Kbyte

eacheach– Need to interface with different equipmentNeed to interface with different equipment– Need to be able to send entire studies many Need to be able to send entire studies many

miles awaymiles away– NightHawkNightHawk

Biomedical EngineeringBiomedical Engineering

• Designing equipment for medical useDesigning equipment for medical use

• Ie: Insulin pump and detectorIe: Insulin pump and detector– Pacemaker/defibrillatorPacemaker/defibrillator– Digital Subtraction AngiographyDigital Subtraction Angiography– StentsStents– Intravascular workIntravascular work

PacemakerPacemaker

• Earl BakkenEarl Bakken

PacemakerPacemaker

• Bakken’s orignal schematicBakken’s orignal schematic

PacemakerPacemaker

• Newer DevicesNewer Devices

PacemakerPacemaker

• Chest XrayChest Xray

PacemakerPacemaker

• Conduction systemConduction system

Ultrasound ImagesUltrasound Images

Magnetic Resonance Magnetic Resonance ImagingImaging

MRI ImagesMRI Images

• Enhancement characteristicsEnhancement characteristics

MRI ImagesMRI Images

• Diffusion Tensor ImagingDiffusion Tensor Imaging

MRI ImagesMRI Images

• MRAMRA

MRI ImagesMRI Images

• Fat saturationFat saturation

MRI ImagesMRI Images

• SpectroscopySpectroscopy

MRI ImagesMRI Images

• Cardiac ImagingCardiac Imaging

MRI ImagesMRI Images

• K-SpaceK-Space

MRI PhysicsMRI Physics

CTCT

• See other lectureSee other lecture

ConclusionConclusion

• Engineering is an excellent base for Engineering is an excellent base for medicine as a researcher, designer, medicine as a researcher, designer, information specialist, or as a information specialist, or as a physician.physician.

Multidetector CTMultidetector CTMark Bechtel, M.D.Mark Bechtel, M.D.

EducationEducation

• Medical School: University of Medical School: University of WashingtonWashington

• Radiology Residency: University of Radiology Residency: University of WisconsinWisconsin

• Musculoskeletal Fellowship: Penn Musculoskeletal Fellowship: Penn State University, Milton S. Hershey State University, Milton S. Hershey Medical CenterMedical Center

Chronological Chronological Developments in Multisclice Developments in Multisclice CTCT• 1971 CT invented by Godfrey Hounsfeld of EMI and independently by Allan 1971 CT invented by Godfrey Hounsfeld of EMI and independently by Allan

Cormack of Tufts University, Massachusetts.Cormack of Tufts University, Massachusetts.• 1974-1976 First Commercial CT scanners (for head CT only)1974-1976 First Commercial CT scanners (for head CT only)• 1976 Whole body CT now available.1976 Whole body CT now available.• 1980 CT now widely available.1980 CT now widely available.• 1989 Introduction of Helical CT by Siemens, Germany1989 Introduction of Helical CT by Siemens, Germany• 1991 Launch of Dual Slice CT by Elscint, Haifa, Israel1991 Launch of Dual Slice CT by Elscint, Haifa, Israel• 1999 Launch of 4 Slice Scanners1999 Launch of 4 Slice Scanners• 2002 Launch of 16 Slice Scanners2002 Launch of 16 Slice Scanners• 2003 Prototype 32 Slicers developed 2003 Prototype 32 Slicers developed • 2003 Prototype 256 Slicers developed (Toshiba) 4D CT2003 Prototype 256 Slicers developed (Toshiba) 4D CT• 2003 Research in Flat Panet Detectors2003 Research in Flat Panet Detectors• 2003 Research in Faster scanning (<0.4 s rotation time)2003 Research in Faster scanning (<0.4 s rotation time)• 2003 Research in Cone Beam CT2003 Research in Cone Beam CT

Multislice CT : A Quantum Leap in Whole Body ImagingMultislice CT : A Quantum Leap in Whole Body ImagingIK indrajit, mn shreeram, jd d’souzaIK indrajit, mn shreeram, jd d’souzaInd J Radiol Imag 2004 14:2:209-216Ind J Radiol Imag 2004 14:2:209-216

• 16 Slice is new standard16 Slice is new standard

• 32 and 64 slice models for cardiac 32 and 64 slice models for cardiac scanningscanning

• New method of use is 3D evaluation New method of use is 3D evaluation versus axial imagingversus axial imaging

Evaluation of a Mandibular Evaluation of a Mandibular LesionLesion

• Left mandibular lesion was scanned Left mandibular lesion was scanned in the axial and coronal planes.in the axial and coronal planes.

• Sagittal, oblique Sagittal and 3D Sagittal, oblique Sagittal and 3D images were reformated.images were reformated.

Mandibular Mass/AbscessMandibular Mass/Abscess

Mandibular Mass/Abscess Mandibular Mass/Abscess 3D3D

Mandibular Mass/Abscess Mandibular Mass/Abscess 3D3D

Comparison of Comparison of ReconstructionsReconstructions

• Comparing lumbar spine Comparing lumbar spine reconstructions from usual reconstructions from usual abdominal CT data sets from a single abdominal CT data sets from a single slice CT scanner and from a 16 slice slice CT scanner and from a 16 slice multidetector CT.multidetector CT.

Comparison of L-Spine Comparison of L-Spine ReconsRecons

3D Reconstruction of Bones 3D Reconstruction of Bones and Fracturesand Fractures

• Multiplanar reconstructions are Multiplanar reconstructions are possiblepossible

• Allows better visualization of Allows better visualization of orientation of certain types of orientation of certain types of fractures.fractures.

• Experienced readers often prefer 2D Experienced readers often prefer 2D reconstructionsreconstructions

3D Hind/Mid Foot3D Hind/Mid Foot

Clavicle Fracture missed on Clavicle Fracture missed on plain filmplain film

Clavicle Fracture missed on Clavicle Fracture missed on plain filmplain film

Clavicle Fracture missed on Clavicle Fracture missed on plain filmplain film

Clavicle Fracture missed on Clavicle Fracture missed on plain filmplain film

CTA of the Lower CTA of the Lower ExtremitiesExtremities

• Fast scanning abilities allows Fast scanning abilities allows scanning of the lower extremities for scanning of the lower extremities for vascular disease.vascular disease.

• Makes conventional diagnostic Makes conventional diagnostic angiography almost obsolete.angiography almost obsolete.

• Can be used for surgical planning.Can be used for surgical planning.

Mesenteric CTAMesenteric CTA

Carotid and Intracranial Carotid and Intracranial EvaluationEvaluation

• CTA is less prone to overestimating CTA is less prone to overestimating stenosis than MRA.stenosis than MRA.

• CTA has replaced conventional diagnostic CTA has replaced conventional diagnostic angiography for evaluation of carotid angiography for evaluation of carotid arteries in many locations.arteries in many locations.

• CTA is excellent for evaluation of CTA is excellent for evaluation of intracranial vessels. It may be as good intracranial vessels. It may be as good as 3D conventional, diagnostic as 3D conventional, diagnostic angiography.angiography.

CTA Intracranial ArteriesCTA Intracranial Arteries

Multidetector CT in Sinus Multidetector CT in Sinus EvaluationEvaluation

• Only need to scan in one plane. All Only need to scan in one plane. All other planes can be reconstructed.other planes can be reconstructed.

Sinus CTSinus CT

Reconstruction

Scanned axially

Routine Cross Sectional Routine Cross Sectional ImagingImaging

• Tube heating is not a problem.Tube heating is not a problem.• Patient can be scanned from head to toes Patient can be scanned from head to toes

in less than 30 seconds making trauma in less than 30 seconds making trauma evaluations with contrast possible.evaluations with contrast possible.

• Multiple phases of contrast enhancement Multiple phases of contrast enhancement can be obtained with single contrast can be obtained with single contrast administration. administration.

• Multiplanar reconstructions of most scans Multiplanar reconstructions of most scans is possible.is possible.

Pulmonary Embolism Pulmonary Embolism EvaluationEvaluation

• Standard of care for evaluation of PE.Standard of care for evaluation of PE.

• Much higher resolution than single Much higher resolution than single slice scanners. (faster scan times, slice scanners. (faster scan times, single breath-hold)single breath-hold)

• Bolus timing still very important.Bolus timing still very important.

Future ExamsFuture Exams

• Coronary CT AngiogramsCoronary CT Angiograms

• Whole Body Trauma ImagingWhole Body Trauma Imaging

• Brain Perfusion ImagingBrain Perfusion Imaging

• 3D Fracture reconstructions3D Fracture reconstructions

WarningsWarnings

• Excessive Radiation from Scanning Excessive Radiation from Scanning too much.too much.

• CT is still not MRI for evaluation of CT is still not MRI for evaluation of soft tissue (ie: disk pathology)soft tissue (ie: disk pathology)

ConclusionConclusion

• 16 slice, multidector CT is very 16 slice, multidector CT is very powerful and can greatly increase powerful and can greatly increase our diagnostic abilities.our diagnostic abilities.

• New possibilities with CT New possibilities with CT angiography are now within reach.angiography are now within reach.

• There is a learning curve.There is a learning curve.

• Don’t overscan.Don’t overscan.