1. OCT Penlight Sara Hanrahan Brock Nichol Gina Rodriguez Areej Sajjad University of Pittsburgh Senior Design - BioE1161

2. Outline Background Objectives Product design specifications OCT Penlight design Results Budget Validation & verification Future work

3. What is Glaucoma? Damage to the optic nerve that may lead to vision loss or complete blindness 66.8 million people with visual impairment 6.7 million suffering from blindness [1] [1] http://www.ahaf.org/glaucoma/about/glabout.htm - Accessed December 4, 2007

4. Possible Cause of Glaucoma Schlemm’s canal clogged, preventing aqueous humor from escaping High intraocular pressure (IOP) Cassin, B. and Solomon, S. Dictionary of Eye Terminology. Gainsville, Florida: Triad Publishing Company, 1990.

5. Canaloplasty: A Promising Solution Expand Schlemm’s canal to relieve IOP New, safe, and minimally invasive technique (do not have to enter anterior chamber) Biggest challenge: surgeon has to find Schlemm’s canal

6. Market Size In 1999, 400,320 glaucoma surgeries were conducted in the US [2] These patients could benefit from the OCT Penlight There are approximately 7,500 hospitals in the US [3] [2] Strutten, Walt, J Glaucoma. 2004 Jun;13(3):221-6. [3]http://www.census.gov/PressRelease/www/releases/archives/facts_for_features_ special_editions/004491.html

7. Optical Coherence Tomography (OCT) Acquires a cross-sectional image of the eye Penetrates about 2 mm into tissue High resolution imaging technology Currently used for diagnostic purposes OCT Handheld

8. Real-Time Tomographic Reflection (RTTR) Stetten, G., Chib, V., Hildebrand, D., Bursee, J. “Real Time Tomographic Reflection: Phantoms for Calibration and Biopsy.” IEEE/ACM International Symposiium on Augmented Reality. 2001 Oct:11-19. New York City.

9. Objectives Long term goal: Locate Schlemm’s canal with more ease during surgery Short term goal: Place a 30 gauge needle into a goat eye guided by the OCT penlight

10. OCT Penlight Components Mechanical Component Calibration Arm

11. Product Design Specifications Place virtual image accurately (100 µm tolerance) Allow a sufficient working area Weigh less than 2 lbs Clamp onto a 3 cm diameter lens Software and hardware capable of acquiring image from OCT device

12. Mechanical Design Virtual image plane must be placed along OCT scanning beam Must be structurally stable Must be fixed display virtual image mirror

13. Electronic System

14. Handheld OCT VGA Signal Splitter Signal Analysis Computer OCT Software Display OCT Penlight Computer OCT Penlight Display Patient VGA Capture Device

15. Handheld OCT VGA Signal Splitter Signal Analysis Computer OCT Software Display OCT Penlight Computer OCT Penlight Display Patient VGA Capture Device

16. Handheld OCT VGA Signal Splitter Signal Analysis Computer OCT Software Display OCT Penlight Computer OCT Penlight Display Patient VGA Capture Device

17. Handheld OCT VGA Signal Splitter Signal Analysis Computer OCT Software Display OCT Penlight Computer OCT Penlight Display Patient VGA Capture Device

18. Handheld OCT VGA Signal Splitter Signal Analysis Computer OCT Software Display OCT Penlight Computer OCT Penlight Display Patient VGA Capture Device

19. Handheld OCT VGA Signal Splitter Signal Analysis Computer OCT Software Display OCT Penlight Computer OCT Penlight Display Patient VGA Capture Device

20. Handheld OCT VGA Signal Splitter Signal Analysis Computer OCT Software Display OCT Penlight Computer OCT Penlight Display Patient VGA Capture Device

21. Handheld OCT VGA Signal Splitter Signal Analysis Computer OCT Software Display OCT Penlight Computer OCT Penlight Display Patient VGA Capture Device

22. Software Capture Screen Crop Display Display our software using OpenGL + GLUT Scale X Scale Y Rotate Translate

23. Calibration Purpose Guide user in positioning the virtual image to its accurate location on the scanning plane Process 3 pins within scanning range Pins scanned and image displayed User aligns virtual image Easily detached 4.5 mm 2 mm

24. Prototype Fabrication Stereolithography (SLA) Lightweight Cost-efficient Sufficiently sturdy Readily available

25. Final Product A: Flexible arm B: OCT Handheld Device C: Lens of OCT D: OLED Display E: Half-Silvered Mirror F: Calibration Arm

26. Calibration Set Up

27. Calibration Process

28. Displaying the Virtual Image mirror

29. Testing the OCT Penlight

32. Validation & Verification Allow a sufficient working area Approved by an experienced ophthalmologist Weigh less than 2 lbs Using a scale, we weighed entire device Clamp onto a 3 cm diameter lens OCT Penlight was able to clamp onto lens and maintain position for at least two hours

33. Validation & Verification Software and hardware capable of acquiring image from OCT device Run the software and see if image on monitor is visible on the Penlight display Placement of virtual image must be accurate (100 µm tolerance) Examine calibration process through a microscope Objective must be met Guide user in penetrating a goat eye with a 30 gauge needle using OCT Penlight

34. Future Work Use a higher quality microscope to obtain clearer pictures of the virtual image Attach OCT Penlight directly to surgical microscope Automate calibration Test Penlight on live specimens Make software faster More efficient video capture

35. Budget Item Approximate Cost Additional Notes Mirror$10Already available OLED Display$800 Rapid Prototyping $300Stereolithography VGA Splitter$100 VGA to USB Video Capture Device $300 Cow Eyes$2.50 each Flexible Arm$38 OCT Scanner$85,000Normally available in most hospitals and does not require purchasing

36. Project Management

37. Acknowledgements Sources of funding Generous gift of Drs. Hal Wrigley and Linda Baker Department of Bioengineering Mentors Dr. George Stetten Larry Kagemann Additional help Andy Holmes Gaurav Shukla Dr. John Galeotti Dr. Bing Wu Dr. Gadi Wollstein

38. Questions