ultrasound imaging

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Ultrasound Imaging

Xiaochen (Sean) Xu1. Medical Business Unit, Texas Instruments

2. NIH Resource on Medical Ultrasonic Transducer Technology, Univ. of Southern California

[email protected]

October 19, 2007

Today & Tomorrow

Challenges & Opportunities

mailto:[email protected]

TI Medical Business Unit Personal medical devices Medical imaging Wireless healthcare systems Implantables

NIH Medical Transducer Center PI: Prof. K. Kirk Shung, Fellow of IEEE(93’), ASA,AIUM Research Areas: Materials, Transducers, and Systems Collaborations: 10+ Universities, 5+ Companies. Personnel: 15+ at USC, 10+ at Penn. State Univ.

Background

http://bme.usc.edu/UTRC/

15M grant available for university medical technology researchhttp://www.ti.com/corp/docs/landing/medtechresearch/index

1. Introduction

2. Ultrasound Imaging: Today

3. Ultrasound Imaging: Tomorrow

4. Opportunities & Challenges for SC

5. Summary

Outline

Introduction Medical Imaging

X-ray, Ultrasound, PET, MRI

Courtesy of google search

Positron emission tomography

Magnetic Resonance Imaging

Introduction Ultrasound Imaging

Real-time Non-invasive Inexpensive and indispensable 2~3 billion annual market in the US New application fields New technologies

Introduction Ultrasound

Sound: Mechanical wave, >20KHz, 2-15 MHz Transducer:

Piezoelectric effects Mechanical wave Electrical wave

Pulse-echo Imaging mode

Signals on Transducer

Tx

Rx

Xducer Target

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Introduction Transducers

Direction of electronic scanning

Active Aperture

Focus 1Focus 2

Oil

Mechanical Mechanical SeSector Scannerctor Scanner Linear ArrayLinear ArrayFocus 1

Phase ArrayPhase Array

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Introduction Transducers

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Lateral Resolution

Axial Resolution

Engery Sensitivity, Vpp, cycle No., Duration, FDA limit

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Introduction Beamformer

Analog BeamformerAnalog Beamformer• Early BF• Low Cost

Digital BeamformerDigital Beamformer• Flexable• Better performance• Dominant in Market

Introduction Typical System

Courtesy of GE

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1. Introduction




5. Summary

Outline

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Ultrasound Imaging: Today Basic Imaging modes

Brightness Mode (B-mode) Doppler Mode (D-mode) Color Doppler Mode (2-D Doppler) 3D & 4D Ultrasound

Courtesy of GE

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Ultrasound Imaging: Today Basic Algorithms

Scan conversion cFFT based Doppler processing Autocorrelation for Color Doppler Image processing 3-D image Reconstruction

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Ultrasound Imaging: Today Basic Algorithms: Scan conversion

Input Data: 30 frame/sec, 2K*256*12bit/frame, ~30M bytesOutput Data:30 frame/sec, 512*512/frame(grayscale or color)

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Ultrasound Imaging: Today Basic Algorithms:

cFFT: Directional Doppler Processing

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Ultrasound Imaging: Today Advanced Imaging Modes

Harmonic Imaging f0 2f0 improved resolution Better contrast

Contrast Agent Injection of air-bubble Improvement of SNR Enhanced harmonic imaging Future targeted contrast-agent

Courtesy of medscape and Biomed Imaging Interv J 2006; 2(2):e17

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Coded-excitation Excite transducer with long pulse Increase energy i.e. Increase SNR & penetration Remain same axial resolution

Chiao & Hao, IEEE UFFC, vol. 52, no. 2, Feb. 2005

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Coded-excitation Barker, Chirp, Golay

Chiao & Hao, IEEE UFFC, vol. 52, no. 2, Feb. 2005

More coded algorithms NEEDED

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1. Introduction




5. Summary

Outline

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Ultrasound Imaging: Tomorrow Better Performance

High resolution Wide application areas

Lower Cost New transducer technology New integrated-circuits

Smaller Size New markets: ambulance, ER, OR Large volume products

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High resolution

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B-mode Imaging: 75μm at 50 MHz, <15μmUltrasound Doppler: <0.5 mm/s in capillariesLess Penetration: <1 cm at 50 MHzAreas: dermatology, ophthalmology, small animal

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Small Animal Applications Preferred animal model (mice and rats)

Fast heart rate

Small physical size

Increasing market (Visualsonics, 25M+ Revenue)

Ophthalmology Applications Retinal vein occlusion

Cornea measurement in LASIK

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HF System with 30MHz arrays

First HF array 30MHz First HF Doppler with arrayFirst HF High-frame System

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30 Frames/s

Rabbit eye images with 30 MHz 64-element Array

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400 Frames/s

Mouse heart images with 30 MHz 64-element ArrayDoppler Images

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HF System with Needle Transducer Retinal vein occlusion (>0.5%) Evaluating occlusion removal surgery Velocity change vs. Occlusion US Doppler with needle transducer

Courtesy of www.mrcophth.com

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HF System with Needle Transducer

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Ultrasound Imaging: Tomorrow Lower Cost

Expensive Transducers Expensive Cables (256 1024 shielded wires) Multi-channel LNA+VCA+ADC+FPGA+DSP

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New Transducer Technology

cMUT (capacitive micromachined US transducers) with integrated AFEPZT Mechanical Diced Transducer

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Reduce Cable Count 1D 2D i.e. 256256*256 wires in cable Integrated AFE to transducer Eliminating impedance mismatch Eliminating cable insertion loss

Example:2D array 2.5 MHz: 39 dB sensitivity improvement US Patent 5744898

cMUT StatusGE & Siemens

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Ultrasound Imaging: Tomorrow Smaller Size

New point-of-care applications Ambulance, ER, bedside care Increasing Market

41% growing 2006, 1 billion by 2012

Courtesy of GE and Acuson

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1. Introduction




5. Summary

Outline

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Opportunities & Challenges Growing Portable Ultrasound Market

GE 174M Sonosite 171M 500M1 Billion in 5 years Zonare 160M

Compactable and Powerful with Low Price ASIC Off-shelf ICs Advanced ICs More Channel Counts

Semi-conductor Industry Volume Counts New Business from cMUTs

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Opportunities & Challenges Wide Operation Voltage

200 Vpp to 1.8V Power Dissipation

<100mW/Ch, LNA+VCA+ADC Low noise & Low power FPGA+DSP+LCD ~10W Laptop size PDA size

Heat Issues Transducer inefficiency: bad to patients and itself Heat dissipation in smaller systems

Summary“Hand-carried ultrasound systems (HCU) set to transform the ultrasound industry landscape .

The HCU market is driven by two technology trends - advanced PC-based architecture and rapid miniaturization.

Hand-carried ultrasound systems can reshape the U.S. ultrasound market in two ways and the industry participants will ultimately decide the direction of the market.”

—U.S. Ultrasound Markets by Frost & Sullivan Research Service

Acknowledgement

Guidance Committee

Dr. K. Kirk ShungDr. Richard M. LeahyDr. Jesse T. YenDr. Jonathan M. CannataDr. Ellis Meng

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NIH Resource CenterDr. Qifa Zhou Dr. Lei Sun Dr. Ruibin LiuDr. Changhong Hu Mr. Jay Williams Dr. Bin Huang Dr. Rachel Bitton Dr. Jin-Ho Chang Mr. Dawei WuDr. Emanuel Gottlieb Dr. Jung-woo Lee Mr. Bruce LaiDr. Johnson Huang Mr. Peter Lee Mr. Joe HanMr. Hyung-Ham Kim Mr. Charles SharpDr. Jianzhong Zhao Ms. S. Sangkatumvong

Doheny Eye InstituteDr. Mark Humayun Mr. Charles DeBoer Dr. Hossein Ameri

The Institute of Genetic MedicineDr. Laurence Kedes Ms. Yan Bai

Acknowledgement

Thank You !Questions?

ultrasound imaging

Documents

colorultrasound imaging

e17 ultrasound imaging

biomed imaging interv

d doppler3d

ieee uffc

axial resolutionchiao

golaychiao hao

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