INNOVATIVE DESIGN FOR REAL-WORLD ENGINEERING PROBLEMS

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CRH O'Regan Orion

Tim

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Procedure Time

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External View

Probe

Houses suction and band

ligation mechanisms

Post-deploymentPre-deployment

• Hemorrhoids afflict 50% of people at some point

in their lives1

• 15 million annual U.S. doctor visits are due to

hemorrhoids2,3,4

• At-home hemorrhoid treatments only offer

symptom relief

• Curative treatments are limited to administration

by specialist medical doctors, such as

gastroenterologists

1Lorenzo-Rivero, S. (2009). Hemorrhoids: diagnosis and current management. Am Surg. 75(8), 635–42.

2Johanson, J. (1990). The prevalence of hemorrhoids and chronic constipation: An epidemiologic

study. Gastroenterol Clin North Am., 98(2), 380–386.

3OECD (2013). OECD Health Data: Health care utilization. OECD Health Statistics (database).

4U.S. Census Bureau, Population Division. (2016) Annual Estimates of the Resident Population: April 1,

2010 to July 1, 2015. United States Census Bureau: American Fact Finder (database).

Rubber Band Ligation (RBL) is a treatment option for

internal hemorrhoids:

Create a medical device prototype which:

• Nominally requires one insertion

• Does not require visualization or

medical grade suction

• Deploys 3 ligation bands at 120

degree increments around the rectum

to treat all local hemorrhoids

• Removes complexity of the procedure

through mechanical automation,

reducing skill requirement

• Small Business Innovation Research (SBIR)

Grant Proposal

• 510(k) FDA Clearance and Market

Introduction

• Possible licensing with larger medical

device company

• Patent coverage based on design project

prototype

The ENDSolutions team would like to thank:

• Dennis Robbins, PhD, Logan Medical

• José Rodriguez, MD, FACP, Logan Medical

• Steven Foland, PhD, University of Texas at

Dallas

• The invaluable UTDesign Staff

Thank you for your unwavering support. We

couldn’t have done it without you all!

Project Motivation Rubber Band Ligation Background Project Goals

Prototype Validation

AcknowledgementsFuture

Final Design: The Orion

Ethics Statement

Ex vivo tissue was used in place of animal

testing and human testing

Contact Team Lead

Andrew Nguyenba

anguyenba@aggienetwork.com

The Orion Medical Device:Treating Internal Hemorrhoids through Rubber Band Ligation

Jesse Grant, Alex Lara Arvizu, Kyle Lo,

Andrew Nguyenba, Aron Torres, Lilian Zhan

Departments of Biomedical and Mechanical Engineering

Sponsored by: Logan Medical DevicesBMEN 4389/MECH 4382

Spring 2018

Trigger

Initiates band

deployment

Trigger Line

Connects

trigger to probe

Description:

• Named after the constellation because

of the 3 stars in Orion’s belt

• Ligates 3 bands simultaneously

• No visualization of hemorrhoids needed

• Disposable design for low cost

Syringe Retractor

Retracts 3 syringes simultaneously

Suction Lines

Connects

syringes to

probe

Operation:

1) Retract syringes to apply suction

2) Wait 30 seconds

3) Pull trigger to displace bands onto tissue

4) Release suction

Performance was compared using objective metrics:

CRH O’Regan

Orion

Pork Rectum with Ligation Bands

The Orion prototype was compared to the CRH

O’Regan, a current market solution.

Chi Squared analysis demonstrates

that the Orion’s performance is as

effective as the CRH in applying

ligation bands onto tissue.

∆ 3mm

3 4Scar Tissue

2

Rubber Band

1Hemorrhoid

Ligation Deviceproduces suction and places rubber band onto tissue

Inside the rectum, tissue near theinternal hemorrhoid is captured viasuction

A 5 mm outer diameter rubber band,called a ligation band, is placed ontothe rectal tissue

The captured tissue atrophies andproduces a scar

The resulting scar locally reducesblood flow, reducing hemorrhoid sizeor eliminating them altogether

1) Tissue Capture Success Rate:

Orion can generate 19% more

suction than the CRH at a 17 mL

volume change in each syringe,

with the Orion projected at 10.3

psi, and the CRH at 8.6 psi.

2) Suction Produced:

y = -3.18ln(x) - 1.2674

R² = 0.9922

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Pressu

re (p

si)

ΔVolume (mL)

Suction Produced

CRH O'Regan

Orion

∆ Pressure

1.66 atm

The Orion captured tissue at a

lower standard deviation of 1.32

mm, compared to 1.68 mm of the

CRH, capturing 12% more tissue at

a higher precision than the CRH.

3) Tissue Capture Height:

Orion was 25% faster with a total

set up and treatment time of 131.4

seconds compared to the CRH at

181.4 seconds for three bands.

4) Procedure Time:

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CRH O'Regan Orion

Heig

ht (m

m)

Tissue Capture Height

2-Tailed T-Test

p < 0.05

83%93%

8%8% 7%

0%

10%

20%

30%

40%

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60%

70%

80%

90%

100%

CRH O'Regan Orion

Tissue Capture Success Rate

Did Not Capture

Captured but disengaged

Tissue Captured

Chi Squared Test

χ2= 2.7462

p = 0.2533

Categorical variables

Independent