Image Technology to Verify the
Placement of Nasogastric Feeding Tubes
to Improve Patient Care Outcomes
Presented
by
Tibor Zajki-Zechmeister
Table of Contents
• Introduction and Background
• Materials and Methods
• Results
• Further Optimization
• Discussion
• Sources
[1]
Nasogastric Feeding Tubes
• Commonly accepted
treatment
• Makes passive feeding
possible
• Wrong placement can cause damages
• Verification method needed
Fig. 1 A standardized feeding tube for passive
patient nutritioning
Current Verification Methods(1)
• Gold standard: X-Ray Imaging
• Alternative methods:
– Auscultation
– Electromagnetic verification
– pH-value test
– Test of aspirated material
Current Verification Methods (2)
• Alternative methods fail to have 100%
correct verifications
Fig. 2 Trials for current alternative verification methods [2]
Alternative Approach
• A basic endoscope is attached to feeding
tube
• Verification takes place
via imaging
• No radiation is needed Fig. 3 Endoscopes are commonly used in
medical environments [3]
Materials and Methods
• A working imaging system requires:
– Camera systems
– Additional components
– Data acquisition process
– Trials if the system is working properly
Components (1)
• Feeding tube
• Camera systems
• Lighting
[4]
Components (2)
• Signal transmission
• Power supply
• Image processing
[5]
[6]
Camera Systems (1)
• Considered camera systems:
Product Number: OV6922 CMOS
Resolution: 320x240 px
Size: 2mm x 2mm x 2mm
Extra tools required: Yes
Price: £ 2
Product Number: MT9V024IA7XTC CMOS
Resolution: 750x480 px
Size: 9mm x 9 mm x 5mm
Extra tools required: Yes
Price: £ 160
[7]
[8]
Camera Systems (2)
• Considered camera systems:
Product Number: IntroSpicio™ 120
Resolution: 220x224 px
Size: 1.2mm x 5mm
Extra tools required: No
Price: £ 3000
Product Number: OVM7692-RAAA CMOS
Resolution: 640x480 px
Size: 3mm x 3 mm x 3mm
Extra tools required: Yes
Price: £ 15
[9]
Data Acquisition (1)
• Images are processed within the following
steps:
– Image captured by camera
– Analog signal transmitted to evaluation board
– Microcontroller converts into digital signals
– Signal transmission to PC via USB-cable
– Output with proper software
Data Acquisition (2)
Fig. 4 Data acquisition process of the micro camera verification system: The images are taken by the cube camera
and afterwards sent to the evaluation board in which the digitalization takes place via the microcontroller. The data is
then sent via USB cable to a PC on which the images can be seen with the software that is provided
Results
• Combination of components is possible
• Data acquisition is
working
• Size is too large for
clinical trials Fig. 5 The prototype 1.0 has too large dimensions
for clinical trials although further improvements
can reduce the general size of the system
Range of Tests
• Tests for Image Quality:
• Fringe Test for Illumination:
Fig. 6 Output of the
cube camera system
and the processing
components: Left:
distant and near
objects imaged; Right:
The NG feeding tube is
imaged to test if near
objects are taken with
a certain sharpness
Fig 7. Image of a
labeled Graph with a
simple LED as the only
light source: Even with
a basic LED the
contrast is high
enough so recognize
the text
Live Demonstration
Further Optimization
• Size reduction via smaller PCBs
• Wireless signal transmission
• Wireless power supply
• Improved lighting
Discussion
• The verification method works in theory
and in practical trials
• Improvements have to be done for clinical
trials
• An efficient and cost effective alternative
has been found
Summary
• Project idea was to create a verification
method via imaging
• Components should be small and cheap
• Imaging output should make a fast
diagnosis of placement possible
Sources
• [1] Macmillan Cancer Support (2012, May) Nutritional support (artificial feeding) [Online]:
http://www.macmillan.org.uk/Cancerinformation/Livingwithandaftercancer/Eatingwell/Nutritionalsupport/N
utritionalsupport.aspx
• [2] Journal of Parenteral and Enteral Nutrition (2001, July) : A Controlled Comparison of Traditional
Feeding Tube Verification Methods to a Bedside, Electromagnetic Technique
• [3] Freie Universität Berlin (2012, May) Endoskopie [Online]: http://www.vetmed.fu-
berlin.de/einrichtungen/kliniken/we15/arbeitsgruppen/ziervoegel/arbeitsbereiche/endoskopie/index.html
• [4] Omnivision Technologies, Inc (2012, May) VGA CameraCubeChip [Online]:
http://www.ovt.com/products/category.php?id=21
• [5] Digi-Key Corporation (2012, May) Cable Mini USB [Online]: http://parts.digikey.com/1/parts-kws/mini-
usb-cable
• [6] Digi-Key Corporation (2012, May) OVM7692-ECJABA0A[Online]:
http://ca.digikey.com/1/5/omnivision-technologies-inc
• [7] 2001 Electronic Components (2012, May) OV6922 CMOS [Online]:
http://www.2k1.co.uk/products/productview.php?wid=28&pageno=2
• [8] Digi-Key Corporation (2012, May) MT9V024IA7XTC CMOS[Online]: http://parts.digikey.com/1/parts-
kws/cmos-camera-sensors
• [9] Medigus (2012, May) 1.2mm camera [Online ]:
http://www.medigus.com/camera_1_2mm/Camera.aspx
Acknowledgement
• WHOCC Charing Cross Campus
– Professor Azeem Majeed
– Elizabeth A. Dubois, MSc
• South Kensington Campus:
– Dr. Dylan Banks
Thank you for your attention