1. In-Vivo Pan/Tilt Endoscope with Integrated Light Source
Tie Hu, Ph. D*, Peter K. Allen, Ph. D*, Dennis L. Fowler, M.D.**
*Department of Computer Science
**Department of Surgery
Columbia University, New York

2. Outline Motivation Introduction Proposed Solution
Prototype Device I and II
Animal Tests
Results and Conclusion
Contributions and Future Work
Acknowledgement

3. Minimally Invasive Surgery

4. Limitations of Standard Endoscope
Paradigm of pushing long sticks into small openings.
Narrow angle imaging.
Limited workspace.
Counter intuitive motion.
Assistants needed to control the camera.
Additional incisions for other laparoscopic instruments.

5. Robotic Surgery Robotic surgery is future of surgery.
Increase the dexterity and fine motion capabilities of surgeon.
Decrease the tremor of surgeon’s hand.
Enable remote operation.
Current surgical robot.
Enormous size.
Extremely high cost.
Multiple assistants needed.
Multiple incisions needed as non-robotic MIS.
Compact and inexpensive surgical robot is needed.

6. In-Vivo Imaging Devices
Rod-lens by Hopkins and cold light source of fiber optics by Karl Storz.
Flexible endoscope using fiber optics to delivery light and transmit image.
Pill camera without locomotion.
Endoscope with rotating mirror.
Endoscope positioned by multilink arm with piezoelectric actuators.
Karl Storz Endoscope
Flexible Endoscope
Pill camera
Gao et al., 1998
Ikuta et. al., 2002

7. Proposed Solution
An insertable surgical robot platform with sensors and effectors in the body cavity where they can perform surgical & imaging tasks unfettered by traditional endoscopic instrument design.
A prototype of a novel insertable Pan/Tilt endoscope with integrated light source.
The incision port is left open access, allowing for single port surgery.

8. Prototype Device I
Stereo camera with 6 DOF are desirable – full mobility
Difficult to achieve in small actuated package
Compromise – 3 DOF per camera
Cameras share tilt axis (1 DOF)
Independent translation (2 DOF)
Independent pan (2 DOF)
Design of 5-DOF insertable camera device

9. Single Camera Prototype I
Diameter: 22 mm; Length: 190 mm
Camera opening: 58 mm
3 DOF: Pan: 120°; Tilt: 130°; Translation: 50 mm
Video

10. Improvements Needed for Prototype II
Much reduced size:
Smaller diameter
Reduce length
Needs light source
Make imaging head modular design
Tradeoff: Degrees-of-freedom for compactness

11. Prototype II 110 mm in length and 11 mm in diameter.
120 degrees Pan/ 90 degrees Tilt.
Integrated 8 LED light source and miniature camera module.
Package to protect the delicate electronics and fragile wires from body fluid and moisture.
Fully sealed camera module.
Joint sealed by rubber boot.
Joystick control.

12. Prototype II (Cont.)

13. LED Light Source
Light-emitting diode (LED) as a light source in laparoscopy:
Lower power
Higher efficiency
Compact package
Longer lifespan
Lower cost
Luxeon portable PWT white LED(LXCL_PWT1)
2.0 X1.6 X 0.7 mm
26 lumens of light at 350 mA
8 PWT LED in a printed circuit board with 9mm diameter.
208 lumens light at 8.4 w

14. Camera Module Pin hole lens (PTS 5.0 from Universe Kogaku America)
Focal length 5.0 mm.
F number 4.
Angle of view D-H-V( ).
6.5 mm CCD camera sensor.
NET USA Inc, CSH-1.4-V4-END-R1.
450 TV lines in horizontal resolution and 420 TV lines in vertical resolution.
Protective window by sapphire.

15. Pan/Tilt Mechanism
Miniature Brushless DC motor (0513G, Faulhaber Group).
25mNm output torque.
5.8 mm in diameter.
Miniature worm gear (Kleiss Gear Inc.)
Gear ratio 16:1.
Compact size.
Increased torque.
Sleeve bearing to reduce the friction of tilt motion.

16. Working Device in the Animal Test

17. Laparoscopic Procedures
Video
Appendectomy
Running (measuring) the bowel
Suturing
Nephrectomy

18. Timing of Each Procedures for Laparoscope and our device
(minutes)
Robot
Running Bowel
4:20
3:30
Appendectomy
2:20
Suturing
5:00
4:00

19. Conclusion
Easier and more intuitive to use than a standard laparoscope.
Joystick operation requires no specialized operator training.
Field of view and access to relevant regions of the body were superior to a standard laparoscope using a single port.
Time to perform procedures was better or equivalent to a standard laparoscope.

20. Contributions and Future Work
Built an insertable camera with Pan/Tilt and integrated LED light source.
Accomplished a series of standard laparoscopic procedures( appendectomy, running (measuring) the bowel, suturing, and nephrectomy) by laparoscopic surgeon using the device.
Future Work
Camera with zoom and auto-focusing capabilities.
Stereo camera in one package.
Function with tool or organ tracking.

21. Acknowledgement
We thank Nancy Hogle for her help in project development and lab support.
This work was supported by NIH grant
1R21EB A1.