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UCSD Photonics
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING Photo: Kevin Walsh, OLR
University of California, San Diego
Jacobs School of Engineering
Design and Prototype Fabrication of a
Neonatal Video Laryngoscope
Katherine Baker and Joseph Ford
October 15, 2009
Wade Rich and Neil Finer
University of California, San Diego
Medical Center
UCSD PhotonicsIntroduction / Motivation
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
Dr. Neil Finer, Chief of the UCSD Medical Center’s Division of Neonatology, and
Wade Rich, Research Coordinator for the Division of Neonatology, approached
the Photonic Systems Integration Lab with a collaboration proposal.
• 25,000 extremely low birth weight infants born annually,
• Most require intubation, a difficult / traumatic process for neonates
• Current instruments designed for adults, not infants, esp. not neonates.
• Project goal: Working model of a neonatal video laryngoscope.
UCSD PhotonicsInfant Intubation
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
85 - 90% of extremely low birth weight infants need intubation.
Intubation requires 3 (average) to 10 tries
Multiple attempts lead to serious risks.
Images from Manual of Emergency Airway Management, ed. Murphy and People’s Daily Online
UCSD PhotonicsLaryngoscopes
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
Our goal was to create a working model neonatal video laryngoscope to
evaluate the feasibility of a commercial device.
Images are from Karl Storz website, GlideScope website
Traditional Laryngoscopes
GlideScope: Video Camera Karl Storz: Coherent Fiber Bundle
Video Laryngoscopes
UCSD PhotonicsBlade and Device Constraints
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
Constraints•Blade Width
•2.5mm by 6.5 mm tip
•Variable Blade Angle
•Image Quality
•Combination of Imager and Lighting
•Mechanical Properties
•Strength
•Heat
•Texture
UCSD PhotonicsImager Selection
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
We identified a promising camera in the Medigus
IntroSpicio CCD Video Camera, with a camera head
measuring only 1.8 by 1.8 by 12 mm.
Effective Focal Length .712 mm
Field of View 100°
F-number f/5.99
0
2
4
6
8
10
12
14
16
18
0 20 40 60 80
Sp
ati
al F
req
uen
cy (
in L
ine P
air
s
per
mm
)
Distance in mm
Maximum Resolvable Frequency
Given Resolution
Measured Vertical Resolution
Measured Horizontal Resolution 0
0.2
0.4
0.6
0.8
1
1.2
0 50 100 150 200
Co
ntr
ast
Spatial Frequency (Line Pairs per mm)
Modulation Transfer Function
Measured MTF for Vertical Lines
Measured MTF for Horizontal Lines
Average Measured MTF
Given MTF
Image from Medigus website
UCSD PhotonicsDesign Solutions
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
The most elegant solution is a tapered
acrylic light pipe acting as the blade.
We make use of a Fraen coupling lens.
With a necessary optical power of at least 30 to 40 mW,
an LED at the tip would dissipate far too much heat.
Calculated efficiency is just over 50%.
Image from Fraen website
UCSD PhotonicsWaveguide Fabrication
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
Acrylic blanks are cut at
the right aspect ratio.
The edges are sanded,
then flame-polished with a
hydrogen-oxygen torch.
Blanks are heated to
pliability, then stretched
to form a taper
UCSD Photonics
Measured efficiency is 28%, but the LED
is bright enough that this is sufficient.
Assembly and Optical Testing of Initial Model
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
Using an Inova X0 LED
flashlight as the handle
and light source, we
created a working model.
Ideal Backlit Target
1 cm 4 cm
LED/Waveguide Lit Target
UCSD Photonics
The medical team tested the device
on a Premi-Blue Neonatal Simulator
(Gaumard).
Medical Testing and Feedback
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
UCSD PhotonicsFinal Model
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
UCSD PhotonicsFinal Model Videos
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
UCSD PhotonicsConclusions and Future Directions
• Neonate anatomy guided our design.
• We met all the constraints of the project.
• Less expensive wafer cameras could be used to reduce cost.
• We would need a sterilizable device to perform a clinical trial
• Further modifications could be made
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
UCSD Photonics
10/26/200
9PHOTONIC SYSTEMS INTEGRATION LABORATORY – UCSD JACOBS SCHOOL OF ENGINEERING
Thank you
