Design of surgical instrument for facilitating an easy process for - - PowerPoint PPT Presentation

Design of surgical instrument for facilitating an easy process for anastomosis in vasculature of all sizes

Anand Parikh ED10B053 Guide: Dr. Venkatesh Balasubramanian

• Performed by plastic surgeons specialized in microsurgery
• Anastomosis of blood vessels of diameter 3mm-5mm
• Requires rigorous training & decades of experience

Microvascular Surgery

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June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 2

Surgeon Shortage

• 1 in 10 plastic surgeons is a microsurgeon
• Only 100 microsurgeons in India (1000 plastic surgeons)
• Increasing demand, increasing physical & cognitive stress
• High deficit of training facilities and institutions in India

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 3

Operational Difficulty

• Micro-anastomosis procedures

have near zero margin for error

• Requires tremendous skill
• 15 years of experience
• Consumes 10-15% of O.R. time

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 4

Existing Solutions

• 1. Acland clamps and sutures (Gold standard)
• Applies to all microvascular anastomosis procedures
• Consumes more time
• Requires high skill
• 2. Vascular Coupler
• Applies to select microvascular anastomosis procedures
• Consumes less time
• Requires high skill

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 5

Treatment gaps

Less skill required Low time consumption Used for all procedures Acland Clamps Vascular Coupler

?

• A novel universal device that reduces the difficulty and
• perating time is needed.

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 6

• A simpler way to perform microvascular anastomosis

in order to provide quicker and error-free treatment

The invention

• 1. Enables all plastic surgeons,

not only microsurgeons, to perform micro-anastomosis

• 2. Can be used in all types of

micro-anastomosis procedures

• 3. Reduces O.R. time

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 7

• Mandibular composite resection & reconstruction from

fibula, on 58 year old male.

Clinical immersion

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 8

Market Size

Global:

• $7 bn global market for surgical devices, 6% CAGR
• $2 bn for non-powered surgical devices

US:

• 6 million reconstructive microvascular procedures annually
• 1% p.a. increase in reconstructive microsurgical procedures

India:

• 8% growth in surgical equipment market

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 9

Constraints

Design

• Minimal deviation from current procedure to create maximal simplicity and

training requirement

• Scalable/modular design for all sizes of vessels
• Manufacturability using conventional techniques

Physical

• Corrosion resistant metallurgy
• Uniform gripping pressure
• Light and compact design

Regulatory

• Class-A medical device according to Indian Law
• 510k under FDA specification

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 10

Concepts

Primary challenge in microanastomosis:

• Ends of vasculature collapses upon occlusion using clamps
• Small vessels are difficult to manipulate under collapsed state

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 11

Preliminary prototypes

• Concepts were filtered based on expert opinion
• Shortlisted concepts were prototyped using CAD and 3D

printing

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 12

Final design

• One concept was chosen based on opinion of domain experts from surgical

and manufacturing backgrounds

• Prior art search report by ipMetrix concluded that the features of this

invention have a high probability of patent grant.

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 13

Validation

• CAD model was validated through static FEA, for both
• perations, occlusion and eversion
• Element name: C3D8R, Mesh Size: 0.3mm
• Max Von Mises Stress = 118MPa, Yield Strength (min) = 170MPa

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 14

Advanced prototyping

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 15

Advanced prototyping

Material

• SS-316L was chosen over SS-304, SS-440, Titanium and Polycarbonate due to
• Better corrosion resistance
• Manufacturability (Excellent weldability and machinability due to low carbon content)
• Commercial availability
• Low cost (relative to Titanium)

Manufacturing

Laser Beam Cutting Forming using dies Assembly using spot-welding

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 16

In-vitro trial

• Chicken carotid artery was used due to its structural similarity to the

human digital artery

• Testing of advanced prototype yielded positive results
• Proof of concept was considered valid
• In-vivo trial suggested after improving the spring action

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 17

Current work

• Drafting of patent application
• Design modifications based on feedback from the trial
• Manufacturing of new prototype for testing SS-316L-SH

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 18

Future work

• Improved advanced prototype
• In-vivo trial
• Prototypes of the device for smaller and larger vessels
• Pilot human trial
• Registration of commercial entity

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 19

Thank you

June 18, 2015 Anand Parikh – ED10B053 Department of Engineering Design, IIT-Madras 20