Revolutionizing local tissue flap design

Our company was created to develop novel utilities and tools to simplify complex procedures performed by doctors. We strive to change the medical landscape by integrating modern computer based modeling solutions with traditional medical instruction and practice. Our company aims to improve surgeon performance and patient satisfaction in hospitals all over the world. flapp is developed with the intent of assisting facial reconstructive surgeons in the operating room.

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In the event of trauma to the face, facial reconstruction is done to conceal the wound site. The common method to conceal the wound is to perform a local soft-tissue flap procedure in which nearby tissue is repositioned to cover and repair the wound site. Local tissue flap design combines a great wealth of medical information, surgical expertise, and case-by-case consideration on the surgeon’s part, proving to be challenging, especially for novice surgeons. When properly done, the original wound area is close to unnoticeable; however, the consequences of improperly designing the initial flap include severe medical and/or aesthetic complications including scarring and tissue death. The resulting revision surgeries represent an additional expense on behalf of the patient and an opportunity cost to the surgeon.

Baker, Shan R. Local Flaps In Facial Reconstruction. Third edition

Key Statistics


Local Tissue Flap Surgeries in 2009


Medical Complication Rate


Scar Revision Surgeries in 2013, averaging $1,800 per surgery

The Need

Thus, there is a need for a method to more effectively plan and get feedback on a particular flap design to prevent complications and reduce the learning curve of flap design.


Our mobile application, called flapp, is a computer-assisted surgery solution that will help surgeons design a local tissue flap properly and prevent the complications mentioned above. flapp provides an interface for surgeons to create and view multiple flap designs on a 3D reconstructed image of a specific patient. For a chosen design, flapp would provide surgeons with information about tension and strain within the closure that would ultimately result in complications. The surgeon can then make edits to the design based on this feedback.

The App Workflow

View App Demo

How we're different

Current surgical planning tools used for cosmetic plastic surgery or craniomaxillofacial surgery are large, expensive, and inaccessible in a modern operating room. Mobile applications provide a 2D visualization tool, but are less powerful than the 3D systems mentioned above. In addition, traditional instruction methods for tissue flap design use a pen-and-paper approach which does not incorporate the 3D complexity of actual patients. flapp combines all of these elements together to provide a powerful tool to practice and implement flap design.

Future Plans

Under the direction of our clinical sponsor Dr. Nicholas Mahoney, we have found a market opportunity with facial plastic surgeons to improve surgical planning and residency learning. With an initial low cost of maintenance, we plan to direct export our beta version of flapp as a free service to pertinent medical practitioners and students, solely as a teaching tool, through connections within the Johns Hopkins School of Medicine. This will required limited regulation as we get feedback from users to improve the fundamental features of the app. If we have success as a teaching tool, we will consider expanding our product as a preoperative planning tool and enter the Class II device regulatory pathway, with Proplan CMF and TraumaCAD Mobile as predicate devices.

Finite Element Analysis

Next steps for our project include developing our finite element simulation suite for the advancement flap (pictured below), getting feedback from residents and surgeons throughout the summer, and continuing to develop the app as we get feedback. We are interested in learning more about the dynamics of different types of flaps.

About Us

The Team

Doran Walsten
BME '16, CBID Master's '17

Teja Polisetty
BME, AMS '19

Kyoung-A Cho
BME, ECE '17

Kendrick Hougen
BME '17

BaDoi Phan
BME '16

Ron Boger
BME '17, MSE CS '17

Patrick Myers
BME '19

Kevin Zhu
BME '19


Nicholas Mahoney M.D.

Department of Ophthalmology, Johns Hopkins School of Medicine, Baltimore, MD 21205

Nicholas Durr, Ph.D

Center for Bioengineering Innovation and Design, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21218

Austin Reiter Ph.D

Department of Computer Science, Johns Hopkins University, Baltimore, MD 21218

Patrick J. Byrne M.D.

Department of Otolaryngology, Johns Hopkins School of Medicine, Baltimore, MD 21205

Ben Kutil

Maryland Institute College of Art, Baltimore, MD 21217

Alison Wong M.D.

Center for Bioengineering Innovation and Design, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21218


May 3, 2016: Design Day
February 25, 2016: Succesfully imported 3D model of Patrick into Android App
February 19, 2016: Named Finalists at the Johns Hopkins Business Plan Competition