Phantom Simulation of Liver Phantom Simulation of Liver Motion During BreathingMotion During Breathing

Group Members:Group Members:Ian DallmeyerIan DallmeyerTuta GuerraTuta Guerra

Ian HenderlongIan Henderlong

Advisor:Advisor:Dr. Bob GallowayDr. Bob Galloway

BackgroundBackground

Over 225,000 people in the U.S. diagnosed Over 225,000 people in the U.S. diagnosed with primary or metastatic liver cancer in with primary or metastatic liver cancer in 2003.2003.

Cancers often spread throughout the liver.Cancers often spread throughout the liver.– Traditional surgery difficult/not possible.Traditional surgery difficult/not possible.

No IGS techniques for the abdomen.No IGS techniques for the abdomen.– Respiratory motionRespiratory motion

PigsPigs– Liver structure different than humans.Liver structure different than humans.

ProblemProblem

Need an anatomically correct model which Need an anatomically correct model which accurately simulates liver motion due to accurately simulates liver motion due to breathing to test IGLS techniques.breathing to test IGLS techniques.

Advantages of Phantom ModelAdvantages of Phantom Model

Porcine LiverPorcine Liver Approx. $1,000 – $2,000 per Approx. $1,000 – $2,000 per

liverliver Not anatomically correctNot anatomically correct Not reusable Not reusable

Phantom modelPhantom model Anatomically correctAnatomically correct Reusable Reusable Time and space-savingTime and space-saving

Alternatives to Modeling Alternatives to Modeling Liver MotionLiver Motion

High-Frequency Jet VentilationHigh-Frequency Jet Ventilation– DisadvantagesDisadvantages

Maximum Duration of 45 min.Maximum Duration of 45 min. Cardiovascular ComplicationsCardiovascular Complications Patient ResponsePatient Response ExpensiveExpensive

Market PotentialMarket Potential

Current methods too Current methods too invasiveinvasive– Open liver resectionOpen liver resection

Estimated market for Estimated market for IGLS 10x current IGNS IGLS 10x current IGNS marketmarket

IGLS: $3.0-$7.5 billionIGLS: $3.0-$7.5 billion Reusable model needed Reusable model needed

to perfect IGLS to perfect IGLS techniquestechniques

Phantom Liver System DesignPhantom Liver System Design

Shape Memory AlloyShape Memory Alloy

Shape memory alloys Shape memory alloys deform upon heatingdeform upon heating– Martensite – low T, Martensite – low T,

soft, deformablesoft, deformable– Austenite – higher T, Austenite – higher T,

hard, non-deformablehard, non-deformable

Other SMA’s - Other SMA’s - CuZnAl, and CuAlNi CuZnAl, and CuAlNi

Alternatives to Modeling Alternatives to Modeling Liver MotionLiver Motion

Linear ActuatorsLinear Actuators– Many Different TypesMany Different Types

– Cost Increases with ResolutionCost Increases with Resolution Linear Actuators with required specs cost $150Linear Actuators with required specs cost $150

http://nanotech.comhttp://nanotech.com

Design SpecsDesign Specs

1-D Linear motion 1-D Linear motion (cranial- caudal) (cranial- caudal)

10.8 10.8 ++ 2.5 mm 2.5 mm (ATLM)(ATLM)

Breath Frequency Breath Frequency ~= .11 Hz. (1 ~= .11 Hz. (1 breath/9 sec)breath/9 sec)

Current WorkCurrent Work

Force determination Force determination

Finalize acquisition of materialsFinalize acquisition of materials

Test cart and recoil systemTest cart and recoil system

Future WorkFuture Work

Construction of power source Construction of power source

Assemble phantom liver sytem in Assemble phantom liver sytem in PVC pipePVC pipe

ReferencesReferences

Herline AJ, Stefansic JD, Debelak JP, Hartmann SL, Wright Pinson C, Herline AJ, Stefansic JD, Debelak JP, Hartmann SL, Wright Pinson C, Galloway RL, Chapman WC. Image Guided Surgery: Preliminary; Feasibility Galloway RL, Chapman WC. Image Guided Surgery: Preliminary; Feasibility Studies of Frameless Stereotactic Liver Surgery. June 1999 Studies of Frameless Stereotactic Liver Surgery. June 1999 Archives of Archives of SurgerySurgery 134:644-650 134:644-650

Tarczy-Hornoch P, Jones D, Zerom B, Woodrum D, and Berk R. Mechanical Tarczy-Hornoch P, Jones D, Zerom B, Woodrum D, and Berk R. Mechanical Ventilators. [Online] Available Ventilators. [Online] Available http://http://weberweber.u..u.washingtonwashington..eduedu/~neonatal/NICU/~neonatal/NICU--WEB/vents.html, 1998. WEB/vents.html, 1998.