• Muscle Volume Analysis• 3D reconstruction allows for accurate volume calculation

• Provides methods for monitoring disease progression• Measure muscle atrophy over extended periods of time

• Aid in preventive and therapeutic disease research• Low cost allows for daily use• MRI too expensive for research purpose

DESIGN PERFORMANCE AND SUCCESSDESIGN COMPONENTSINTRODUCTION• Amyotrophic Lateral Sclerosis (ALS) is a progressive

neurodegenerative disease that causes atrophy of voluntary muscles through degradation of motor neurons

• Size and shape of muscles like the bicep are good indicators of the severity of the disease

APPLICATIONS

DESIGN CRITERIA

Tracking System:• Provide linear location on a 3-D coordinate system at each

acquisition point• Provide angular orientation at each acquisition point

• Roll, pitch, and yaw• Have an acquisition rate that matches the US acquisition

rate• Have error that is less than or equal to the error from the

US machine3-D Reconstruction Software:• Translate slice location to patient location• Rotate the image according to the angular data• Recognize muscle tissue• Compute muscle volume

SYSTEM VERIFICATION

FUTURE DIRECTIONS

• Construct a stable attachment device to connect the position sensors and the US probe

• Design a more efficient infrared LED arrangement for position tracking of US probe

• Explore different methods of obtaining x, y and z position of US probe to increase accuracy• Use of other accelerometers and gyroscopes

• Streamline software for a more user friendly data analysis• Determine methods to reduce effects of sensor drift• Devise a more accurate scaling for Wii-Motion+ output

ACKNOWLEDGEMENTS

Special Thanks to our advisor Dr. Christopher Lee M.D. of the Vanderbilt Department of Neurology, Dr. Paul King, graduate student advisor Alex Makowski, VUMC for the use of a Sonosite Titan, Nintendo, Jordan Brindza and Jessica Szweda of Notre Dame for the WiiLAB software package and manuals, and Knuckles904 for help with the Wii-Motion+ Arduino code.

Figure 4. The Arduino prototype board

Figure 9. Position and angle data for each acquisition slice for both systems. LED System (Left). LED + Wii MotionPlus System (Right)

• Magnetic Resonance Imaging (MRI) is the gold standard for muscle imaging, but is expensive and immobile

• Ultrasound (US) imaging gives comparable 2D images, is cheaper, mobile, and has shorter acquisition times

Wii System Components to Track Ultrasound Probe and Create 3-D ImagesWii System Components to Track Ultrasound Probe and Create 3-D Images Van Gambrell, Laura Owen, Steven Walston, Jonathan WhitfieldVan Gambrell, Laura Owen, Steven Walston, Jonathan Whitfield

Advisor: Dr. Christopher Lee M.DAdvisor: Dr. Christopher Lee M.D..

Figure 1. Diagram of normal and ALS affected muscle and neural system

Figure 7. Linear error from LED system

•Tested by moving source on a fixed path with known distance•Compared measurements with returned data

•Created a phantom for volume accuracy•To compare US and MRI

•Linear error is greater than that of the ultrasound system•US system error is within 3 percent compared to 22, 31, and 2 percent

•System failed accuracy verification

Figure 8. Drift from Wii Motion+ with movement only from 17-27 seconds

•External IR interference negatively affected ability to accurately track LEDs•Reconstruction Software:•Resolution reduced from 640x480 to 160x120 in order to function within memory constraints of MATLAB

•Scans limited to less than 15sec due to Wii-Motion+ sensor drift• Angle and position data filtered due to significant noise

Figure 2. MRI slices used to create 3-D muscle image

Figure 3. Ultrasound images used to approximate 3-D muscle image

•Wii-mote•Infrared camera capable of tracking 4 infrared (IR) light sources•Bluetooth data transmission

•Wii-Motion+•Provides yaw, pitch and roll info

•Arduino Prototype board•Interfaces between Wii-Motion+ and MATLAB to acquire yaw, pitch, roll

•Sonosite Titan •Small portable Ultrasound machine•2D Linear array transducer

•Design Function•Two Wii-motes are placed in a known location and orientation

• Used to calculate the position of the US probe in 3-D space

•Wii-Motion+ provides rate of change in yaw, pitch and roll

•Integrated to provide the angular orientation of the ultrasound probe

•IR LEDs were tested as a redundant source of yaw, pitch and roll angular data•Each acquired US image is assigned a x, y, and z position and a yaw, pitch and roll angle from the Wii-motes and Wii-Motion+

•3-D Reconstruction Software•Takes position data and realigns slices in new matrix representing scanned area•Uses angle data to rotate slice appropriately•Done through post processing

Figure 5. Arduino with LED + Wii MotionPlus attached to US probe

Figure 6. LED+WiiMotionPlus System with Sonosite Titan