Craniofacial Phenotyper Freshman Imaging Project Sean Cooper Rebecca Klein

What is Imaging Science? Combination of Physics, Mathematics, Engineering, and Computer Science Studies technology behind scientific images Applies this to scientific research It is a multidisplinary field having to do with (1) fundamental theoretical basis behind all technologies that go into imaging devices (2) deals with how technologies are integrated into imaging systems that perform specific imaging related functions (3) how the systems are applied/ used generally in scientific research http://www.cis.rit.edu/

Motivation Researching a new way of assessing the difficulty of intubation as opposed to traditional methods Jack is an University of Rochester Medical Center Anesthesiologist and associate professor. Bo Hu is a researcher at U of R. Together they are working to create a new practice to figure out if someone can be intubated. Intubation helps with breathing during surgery. Currently, the common practice is to give someone anesthia and try to stick the tube down the throat. If this cannot be done, the person is then intubated through the trachea. This is a very discomforting procedure to the patient as well as invasive. Bo and Jack’s theory is that using a 3D image of a person and extracting measurements between seven points on the face along the curvature and lower face volume can determine if a person can or cannot be intubated. This is to be used in an everyday physican’s office Picture given via email http://www.cs.rochester.edu/research/vision/people/Bo_Hu/ JACK WOJTCZAK URMC ANESTHESIOLOGIST Jack_Wojtczack@URMC.Rochester.edu BO HU U OF R RESEARCHER bhu@cvs.rochester.edu

Our Assignment Build a Craniofacial Phenotyper Take a 3D image of the head Use 3D image generated to find certain measurements Asses the difficulty of intubation for a specific patient Build a system that can take a 3D image of the face. Use the 3D image and take the points along the curve.

What are we Measuring? Distance following the curvature of the face (3DS) Between 7 points on the face Also finding the volume of the head N Nasion SN Subnasion T (L+R) Tragion GN Gnathion GO (L+R) Gonion

Basic Requirements Accuracy: Our goal is ± 0.5 mm Cost: Our goal is $3,000 Speed: 1 to 2 second capture time, quick processing time Robust: small, will not break easily, can be used in a variety of environments; easy/unnecessary calibration Causes no harm to the patient Scanner will mainly be used in Physician’s office – anesthesiologist evaluating patient for intubation Other uses: - pulmonary physician evaluating a patient with sleep apnea - plastic surgeon evaluating a face for use in corrective surgery Since it will be in a physician’s office and not used in an emergency room setting, it doesn’t need to be portable. However, it should take up as little space as possible. The cost of the scanner is a big factor when it comes to design – the entire point of Freshman Imaging Project is to engineer a new system which is just as good (or better) as existing systems which costs significantly less than existing systems. The time it actually takes for the system to take a full scan of the patient’s head should be under five seconds. If it takes longer than five seconds, there is a greater chance that the patient’s head will move – making the scan inaccurate. The user interface should be easy enough to use so that anyone with a small amount of basic training would be able to completely understand what to do. Of all the requirements for the system, the most important is how the system affects the patient. There should be NO NEGATIVE SIDE-EFFECTS as a result of using our system.

What is 3D capture? MAYBE ADD PICTURE? SOMETHING TO FILL IN WHITE SPACE Put in 3d image

Methods of Depth Capture Time of Flight A laser is pulsed Distance is measured from the time it takes for the pulse to return Geometrical Emitter + Sensor at different positions Triangulation Time of flight: The emitter and sensor are in the same place. An emitter sends out a pulse of light and based on the amount of time it takes to return to the sensor determines the distance based on the speed of light. Geometrical: the emitter and sensor are at different positions. The depth is calculated using triangulation (trigonometry and geometry)

Triangulation Using geometry it is possible to determine depth if you know: The distance between the sensor and the laser (D) The angle of incidence (Z) Z D SENSOR LASER

Point Cloud An output format of a 3D scanner (.ply) Creates a collection of spatial coordinates From this a mesh (.obj) can be created and surface distances along the curvature can be measured Point cloud bunny http://www.engineeringspecifier.com/public/primages/pr1200.jpg Mesh bunny http://www.farfieldtechnology.com/products/toolbox/pointcloud/bunny1w.jpg

Equipment Surveys ADD MORE Intro to what we’ve looked into – as a transition slide Bulleted – what we’ve looked at

FaceGen Add the three photos of rose on the left (the different views) September 15, 2011

Kinect

Kinect’s infared dots (stand in front of screen)

LiDAR http://www.saic.com/geospatial/images/lidar1.jpg

Structured Light Scanner

DAVID Laser Scanner http://www.david-laserscanner.com/

difficult to calibrate DAVID Laser Scanner Good Fair Poor Portability Accuracy (± .5mm) Robustness Speed Cost Kinect   LiDAR (Time of Flight) Structed Light difficult to calibrate  DAVID Laser Scanner Line Scanner 20 minute capture time Z-Scanner Modulated Light C3D Stereoscopic System Photometric System Silhouette Conoscopic Holography

Extract measurements from point cloud data Schedule Fall • Research • Equipment Surveys • Demonstrations of 3D capture • Pugh Analysis (narrowing down to 3 options) PDR Prelimary Design Review Winter Continue with Pugh Analysis • Trade off studies to test different options • Develop a design (by week 7) • Choose final system option(s) and create Work Breakdown Structures for each CDR Critical Design Review Spring • Complete final design • Buy components • Build system(s) • Test system(s) • Have final product for Coding Research to understand theories of Software Extract measurements from point cloud data

Questions?