Ischemia Sensing Smart Organ Retractor: ____________________________________________________________

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Ischemia Sensing Smart Organ Retractor__________
__________________________________________________
__________________________________________________
_________The Effects of Force on Ischemia over
Time

• Jen Horwat
• John Yu
• Sunipa Saha
• Mentors
• Greg Fischer,
• Mark A.Talamini, MD

MISTC Lab, Johns Hopkins Hospital
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Overview

• Problem Detection of ischemia intra-operatively
• Solution The Smart Organ Retractor
• Placement of force and ischemia sensors on the
  Smart Organ Retractor will allow measurement of
  the effects of retractor force on ischemia in the
  tissue over time

Photo from 3/5/03 experiments in MISTIC
Photo from 3/5/03 experiments in MISTIC
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Overview

• Problem Detection of ischemia intra-operatively
• Solution The Smart Organ Retractor
• Placement of force and ischemia sensors on the
  Smart Organ Retractor will allow measurement of
  the effects of retractor force on ischemia in the
  tissue over time

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Motivation

• Organs are retracted to
• provide access to the target
• area and a clear field of view
• Clinical Studies
• intraoperative retraction can
• produce ischemia in the affected
• tissue
• CT Liver Study
• Spinal Cord Fusion Study

www.adhb.govt.nz/trauma/ presentations/Forums/live
rats/ sld001.htm
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Motivation

• Problems with current pulse oximeters
• Alternate Therapies
• Modified Liver Retractor
• Goal
• Prevention rather than treatment
• Reduce ischemic damage to organ tissue during
  surgery

www.karlstorz.com/hm/ getframe.html?2_products/
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Motivation
www.innomed.net/InnoHip1.htm
www.karlstorz.com/hm/getframe.html?2_products/
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Previous Work

• Smart Organ Retractor, Greg Fischer
• Optical technology
• similar to pulse
• oximetry
• Ischemia Sensors
• Limitations
• Inconsistent readings for different tissues
• Calibration
• No method for measuring force of retraction

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Previous Work
Deaver Retractor
6 DOF F/T
Emitter Receiver
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Previous Work
Smart Organ Retractor
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Previous Work
Strain Gauges
Full Bridge for each axis
Babcock Retractor
Emitter
Receiver
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Pulse Oximetry
www.wardray-premise.com/engineering_services.htm
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Pulse Oximetry

• Measures amount of oxygenated hemoglobin in the
  blood
• Greatest difference in absorption
• by oxygenated and deoxygenated
• hemoglobin at 660nm and 880-940nm
• SOR - Measures reflected light
• through tissue

www.wardray-premise.com/ engineering_services.htm
Casciani, J., Pulse Oximeter and Sensor
Optimized for Low Saturation, Aug. 2001.
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Pulse Oximetry
Casciani, J., Pulse Oximeter and Sensor
Optimized for Low Saturation, United States
Patent No. 6,272,363, Aug. 2001.
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Pulse Oximetry
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System Diagram
Controller
In-Circuit Serial Programmer
Serial Interface
PIC Microcontroller
Programming Port
Digital I/O
Retractor
Serial Port Interface
Digital/Analog Converter
16x
8x
Amplifier
LEDs
Analog/Digital Converter
Amplifier/ I-to-V Converter
2x
2x
Photodiode
Programmable Potentiometer
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System Diagram
Controller
In-Circuit Serial Programmer
Serial Interface
PIC Microcontroller
Programming Port
Digital I/O
Retractor
Serial Port Interface
Digital/Analog Converter
16x
8x
Amplifier
LEDs
Analog/Digital Converter
Amplifier/ I-to-V Converter
2x
2x
Photodiode
Programmable Potentiometer
Force Sensors
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System Diagram
Hamamatsu Photodiode
www.hamatsu.com
SunLED
www.sun-led.com
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System Diagram
Photodiode
LED
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Overview of Deliverables
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Minimum Deliverables
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Overview of Deliverables
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Medium Deliverables
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Overview of Deliverables
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Maximum Deliverables
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Calibration
SPO2 Simulators Index 2XL, Fluke Biomedical,
www.flukebiomedical.com/.
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Experiments at MISTC
MISTC Lab, Johns Hopkins Hospital
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Schedule
March
April
May
mid-March
mid-April
Reprogram PIC Preliminary Calibration
Consistent Readings Force sensors on manual
and da Vinci retractors
Preliminary experiments Ischemia sensors on da
Vinci retractor
More experiments with manual retractor
Modifications to manual retractor Experiments
with da Vinci retractor
Sensor pattern on manual retractor
Complete Minimum and Medium Deliverables
Preliminary experiments for pattern
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Project Management

• Team Management
• Funding
• Funded by Engineering Research Center
• Materials
• Free samples from manufacturers, if possible
• Retractors and da Vinci tools provided by Johns
  Hopkins Hospital and Intuitive Surgical, Inc.
• Progress Checkpoints
• Weekly Meeting with Mentor
• Greg Fischer Monday 11am
• Dr. Talamini Friday 3pm Surgeons Meeting

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Main References

• Adult Cardiac Surgical Instruments Sternal
  Retractor for Valve CABG Surgery, Genesee
  BioMedical, Inc., http//www.geneseebiomedical.com
  /.
• Casciani, J., Pulse Oximeter and Sensor
  Optimized for Low Saturation, United States
  Patent No. 6,272,363, Aug. 2001.
• Diab, M., E. Kiani-Azarbayjany, Low Noise
  Optical Probe, United States Patent No.
  5,638,818, June 1997.
• Diab, M., Manual and Automatic Probe
  Calibration, United States Patent No. 6,397,091,
  May 2002.
• Germer, C., Optical Properties of Native and
  Coagulated Human Liver Tissue and Liver
  Metastases in the Near Infrared Range, Lasers in
  Surgery and Medicine, 23194-203, 1998.
• Liver Retractor, Karl Storz Endoskope
  Laparoscopy Products. http//www.karlstorz.com/hm/
  .
• Lownie, S., X. Wu, S. Karlik, A. Gelb, Brain
  Retractor Edema During Induced Hypotension The
  Effect of the Rate of Return of Blood Pressure,
  Neurosurgery, 27(6)901-5, 1990
• Ritch, R., W. Shihadeh, J. Liebmann, A
  Conjunctival Retractor for Glaucoma Filtering
  Surgery, Ophthalmic Surgical Lasers Imaging,
  35(3)261-2, May-June 2004.
• SPO2 Simulators Index 2XL, Fluke Biomedical,
  http//www.flukebiomedical.com/.
• Yassa, N., J. Peters, CT of Focal Hepatic Injury
  Due to Surgical Retractor, American Journal of
  Roentgenology, 166599-602, 1996.