Interactive 3D Knowledge Platform for Reconstructive Plastic Surgery
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Självständigt arbete i informationsteknologi
15 juni 2022
Interactive 3D Knowledge Platform
for Reconstructive Plastic Surgery
Aria Assadi
Kevin Hormiz
Faizan Mian
Oskar Rick
Carl Wallskog
Civilingenjörsprogrammet i informationsteknologi
Master Programme in Computer and Information Engineering
Abstract
Institutionen för Interactive 3D Knowledge Platform for Recon-
informationsteknologi
structive Plastic Surgery
Besöksadress:
Ångströmlaboratoriet
Lägerhyddsvägen 1, hus 10 Aria Assadi
Postadress:
Kevin Hormiz
Box 337 Faizan Mian
751 05 Uppsala Oskar Rick
Carl Wallskog
Hemsida:
https://www.it.uu.se
There is a lack of technical platforms where reconstructive surgeons
around the world can share their knowledge and experience. This prob-
lem is especially prevalent in developing countries, where surgeons rely
on inadequate means for preparing operations. This project is called
Lambå-Atlas and addresses this issue by providing the surgeons with an
intuitive website. It consists of an interactive human 3D model, where
surgical instructions are accessible by clicking on the respective body
parts. The purpose of Lambå-Atlas is to assist reconstructive surgeons
with suggestions and assessments of suitable surgeries based on the re-
quired medical equipment and experience. The goal of this project was
to create an educational platform that promotes knowledge exchange.
Lambå-Atlas has achieved this by providing a website that aids recon-
structive surgeons by letting them navigate a 3D human model and sug-
gest suitable surgery instructions based on a chosen body part.
Extern handledare: Dr. Olof Engström och Dr. Morten Kildal vid Akademiska sjukhuset
Handledare: Mats Daniels, Martin Eriksson, Björn Victor och Tina Vrieler
Examinator: Björn Victor
Sammanfattning
Det finns en brist på tekniska plattformar där rekonstruktionskirurger runt världen kan
dela med sig av sin kunskap och erfarenhet. Detta problem är allmänt förekommande i
utvecklingsländer där kirurger förlitar sig på inadekvata medel för operationsplanering.
Detta projekt kallas Lambå-Atlas och löser problemet genom att förse kirurgerna med
en intuitiv hemsida. Den består av en interaktiv mänsklig 3D-modell där tidigare doku-
menterade operationer är åtkomliga genom att klicka på de respektive kroppsdelarna.
Syftet med Lambå-Atlas är att hjälpa rekonstruktionskirurger hitta lämpliga operationer
baserat på deras tillgängliga medicinska utrustning och erfarenhet. Målet med detta pro-
jekt är att skapa en utbildningsplattform som främjar utbyte av kunskap. Lambå-Atlas
uppnår detta genom att förse kirurger med en hemsida som hjälper dem hitta lämpliga
operationsinstruktioner. Genom att navigera en 3D-människomodell kan en kirurg hitta
instruktioner baserat på en vald kroppsdel.
ii
Contents
1 Introduction 1
2 Background 3
2.1 Uppsala University Hospital Partnership . . . . . . . . . . . . . . . . . 3
2.2 Plastic Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2.1 Flap Surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.3 Access to Electronic Devices in Developing Countries . . . . . . . . . 4
2.4 3D-modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3 Purpose, Aims, and Motivation 5
3.1 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1.1 The Need for Lambå-Atlas . . . . . . . . . . . . . . . . . . . . 5
3.2 Aims . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.2.1 Sustainable Development Goals . . . . . . . . . . . . . . . . . 6
3.3 Ethical Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.3.1 Representation on the Main Page Human Body . . . . . . . . . 6
3.3.2 Pictures from Previous Surgeries . . . . . . . . . . . . . . . . . 8
3.3.3 Functionally over Appearance . . . . . . . . . . . . . . . . . . 8
3.4 Delimitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
4 Related Work 9
4.1 Similar Purpose and Functionality to Lambå-Atlas . . . . . . . . . . . . 9
4.1.1 Microsurgeon.org . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.1.2 Touch Surgery: Surgical Videos . . . . . . . . . . . . . . . . . 10
4.2 Similar Design to Lambå-Atlas . . . . . . . . . . . . . . . . . . . . . . 10
iii
5 Method 10
5.1 Choice of Software Platform . . . . . . . . . . . . . . . . . . . . . . . 10
5.2 Designing a Prototype in Figma . . . . . . . . . . . . . . . . . . . . . 11
5.3 Front-end Programming Language . . . . . . . . . . . . . . . . . . . . 13
5.4 JavaScript Libraries . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.5 Handling 3D Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.5.1 3D-file Formats . . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.5.2 Modifying 3D Objects . . . . . . . . . . . . . . . . . . . . . . 14
5.6 Building the Back End . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.7 Choice of Database . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6 System Structure 16
6.1 Admin and Client Site . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.1.1 Admin Site . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.2 CRUD and User Permissions . . . . . . . . . . . . . . . . . . . . . . . 17
6.3 Communication Between the Front End and Back End . . . . . . . . . 17
6.4 Server and Database Communication . . . . . . . . . . . . . . . . . . . 18
7 Requirements and Evaluation Methods 18
7.1 User Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7.2 Evaluation of User Tests . . . . . . . . . . . . . . . . . . . . . . . . . 19
8 Implementation of the 3D Model 19
8.1 Dividing the 3D Body Into Body Parts . . . . . . . . . . . . . . . . . . 19
8.2 3D-modeling Software . . . . . . . . . . . . . . . . . . . . . . . . . . 20
9 Results and Discussions 21
iv10 Future Work 22
10.1 Local Data Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
10.2 Storing Patient Information . . . . . . . . . . . . . . . . . . . . . . . . 22
11 Conclusions 23
A Admin Page 29
B User Tests 31
C Survey Results 34
v1 Introduction
1 Introduction
Reconstructive surgery is a procedure for restoring lost or injured body parts or tis-
sue [52]. For instance, in a case where the tissue of a hand has been damaged, this type
of surgery helps restore its function and aesthetics. Surgeons in the area of reconstruc-
tive surgery find it difficult to plan and perform surgeries due to a lack of accessible
information. This problem is especially prevalent in developing countries such as Tan-
zania, Ethiopia, and Palestine where surgeons have to rely on surgical instructions from
YouTube videos to prepare for surgery [41]. In order to solve this problem, a web-
site that can assist reconstructive surgeons all around the world in preparation for and
execution of surgeries, has been created.
Lambå-Atlas is a collaboration between students at Uppsala University and the plastic
surgery team at the University Hospital in Uppsala. The word “lambå” is the Swedish
word for “flap”, which refers to tissue on the body. Flap surgery is the act of transferring
a unit of tissue from one site of a human body to another while maintaining the tissue’s
blood supply. The University Hospital has provided learning material with instructions
on different reconstructive surgeries, which has been used to create a website where the
user can access these.
Upon entering the website, the user is presented with a 3D male human model, that
can be rotated, zoomed, and clicked. When clicking on a body part, the user will be
navigated to a page consisting of instructions for reconstructive surgeries relevant to the
chosen body part (see Figure 1). Because the surgeries differ in difficulty and material
requirements, the instructions for the surgeries will be sorted by both those require-
ments. This is done by giving every instruction two ratings, one for difficulty and one
for material requirements. The ratings range from one to three, where a three in diffi-
culty represents that the surgery is difficult to perform in regard to surgical experience.
A three in material requirement represents that the surgery requires advanced medical
equipment. As both ratings descend, the difficulty and material requirements become
less advanced. After taking part of the surgical instructions, surgeons can leave a one to
five-star rating, depending on the usefulness of these.
11 Introduction
Figure 1 Lambå-Atlas menu showing surgical instructions for the trunk
Although Lambå-Atlas can be used by any reconstructive surgeon, its purpose is to
simplify for those surgeons who do not have the option to search for information in
medical databases. With the growth of Lambå-Atlas, surgeons across the world will
have uniform information about reconstructive surgery.
Acknowledgement We would like to express our sincere appreciation to our exter-
nal supervisors, Dr. Morten Kildal and Dr. Olof Engström, for the continued support
and encouragement throughout the project, as well as providing us with the material
needed. We are also grateful for the ability to work on this project, and the learning
possibilities provided by Uppsala University Hospital.
Declaration of division of labor The division of labor has evenly been distributed
in the group. Faizan Mian and Kevin Hormiz have mainly focused on developing the
design and front-end code for the website. Carl Wallskog has been responsible for
the 3D-modelling of the human body and has also contributed to the development of
front-end code for the website. Aria Assadi och Oskar Rick have mainly focused on
developing the database and API. The corresponding parts of the report have mostly
been written by the respective person. Other parts of the report have been addressed
cooperatively by all authors.
22 Background
2 Background
In this section, a few of the areas relevant to the project will be explained. Firstly,
the stakeholder of the project, Uppsala University Hospital, will be introduced with a
background as to what they are and how they work. Secondly, reconstructive plastic
surgery and its relation to the project will be described. Furthermore, the access to
electronic devices in developing countries and the possibility of 3D-modelling for this
project, will be discussed.
2.1 Uppsala University Hospital Partnership
At the department of plastic surgery at Uppsala University Hospital, surgeons perform
reconstructive plastic surgery, which is described as the restoration of a patient’s func-
tionality and appearance after tumor disease, severe body injury or malformations [25].
With the help of state-of-the-art machinery, a team of professional surgeons and nurses
treat over 150 patients every week [25]. The University Hospital is not only active in
Sweden but collaborates with other countries such as Tanzania, Palestine, and Ethiopia.
Dr. Morten Kildal, the external supervisor for this project, is part of the team traveling
to these countries, educating surgeons on how to perform reconstructive surgery. After
visiting and educating surgeons in these countries, Dr. Kildal experienced that surgery
preparations were inefficient. The reason for this is that surgeons had to —while search-
ing for surgical information— examine material that was spread across books, articles
and online videos, making the preparation inefficient.
2.2 Plastic Surgery
Plastic surgery is a surgical specialty that includes altering of a person’s appearance,
and restoration or reconstruction of facial and body tissues. It can be divided into two
categories, namely cosmetic surgery and reconstructive surgery. Cosmetic surgery fo-
cus on improving a person’s appearance, while reconstructive surgery is used to recon-
struct a body part or improve the function of it. Some types of body abnormalities that
reconstructive plastic surgery is used for are caused by, diseases, trauma, tumors and
developmental abnormalities [30].
32 Background
2.2.1 Flap Surgery
Although reconstructive surgery does not exclusively consist of flap surgery, in this
report, both terms are used interchangeably. Flap surgery is namely a technique used
in reconstructive surgery, where surgeons try to transport healthy live tissues from one
location of the body to another whilst preserving blood supply to the new area. It is
practiced in those areas of the body that have lost skin, fat, muscle movement, and/or
skeletal support due to severe injuries or diseases [52]. Lambå is the Swedish translation
of the term flap, hence creating the origin of the project’s name. The name Lambå-Atlas
is referring to the website as an atlas containing a collection of flap surgeries on the
human body.
2.3 Access to Electronic Devices in Developing Countries
In order for Lambå-Atlas to function all around the world, including developing coun-
tries such as Tanzania, Ethiopia and Palestine, a few aspects need to be considered. The
access to electronic devices vary in different parts of the world. In general, the access to
mobile phones is greater than the access to desktops and tablets [53], something that is
especially true in developing countries [54]. In order to create a platform that is accessi-
ble in all parts of the world, Lambå-Atlas needs to be available and suitable for mobile
phones.
2.4 3D-modelling
3D-modelling is the process of developing an object simulated in 3D-space. This can be
traced back to Ancient Greece, where Euclid developed ideas about geometry that in-
spired many 3D-modelling techniques. Computer-aided design, more commonly known
as CAD, developed in the 1950s, is more in-line with what 3D-modelling is today [56].
3D-modelling is widely used in movies and video games, and assist with creating com-
plex scenes that would be hard to recreate in real life. In addition to this, 3D-modelling
is also used in architecture, engineering, and advertisements. 3D-modelling is used with
specialized 3D-softwares that is used to create and manipulate points in space, called
vertices. A collection of the vertices forms a mesh, that also creates an object [51]. 3D-
modelling is important for Lambå-Atlas user interface, a human body, that is created
using 3D-modelling.
43 Purpose, Aims, and Motivation
3 Purpose, Aims, and Motivation
In this section, the importance of a platform for knowledge exchange in the field of
reconstructive surgery will be discussed, along with the aims and motivations for this
project. Another subject such as ethical aspects is also explored due to its relevancy to
our project. The delimitations of the project are also discussed.
3.1 Purpose
The purpose of Lambå-Atlas is to reduce the time that reconstructive surgeons spend on
searching through books, articles, and videos by gathering information from different
surgeries into one platform. Other than reducing the time spent on research before
surgeries, the platform will also be helpful while educating new surgeons in the field of
reconstructive surgery. In low income countries, where the availability of research can
be limited, fewer patients might be treated due to a lack of knowledge [41], something
which this project aims to improve.
3.1.1 The Need for Lambå-Atlas
In an article written by Frank Fang and Kevin C. Chung, they discuss how flap surgery
has evolved throughout history. They state that one of the factors in the development
of flap surgery of the upper extremity —i.e., the part of the body that includes the arm,
wrist, and hand [43]— is knowledge exchange [32]. By providing a platform such
as Lambå-Atlas where reconstructive surgeons around the world can share and access
knowledge, we hope to contribute to further development of flap surgery. Fang et al.
further state that “trauma generated by the maiming insults of war and industry” (p. 1)
is a factor that historically has —because of its complexity— developed the practice
of flap surgery for the upper extremity. This shows the necessity of introducing an
application like Lambå-Atlas in countries where such injuries are prevalent.
3.2 Aims
The website aims to achieve a few long-term goals. One of the main goals is to create a
platform that promotes knowledge exchange and education for reconstructive surgeons.
Another goal for Lambå-Atlas is that it should contain information suited for all recon-
structive surgeons, regardless of their experience or medical equipment. As previously
53 Purpose, Aims, and Motivation
described in Section 1, a rating system for difficulty and material requirement will be
available for all surgical instructions on Lambå-Atlas. If there are enough instructions
for every body part where every combination of ratings is covered, this goal will be
fulfilled.
3.2.1 Sustainable Development Goals
The United Nations have a collection of 17 numbered goals called the Sustainable De-
velopment Goals (SDGs) which address global challenges such as poverty, inequality,
education, and climate change [58]. The fourth goal is about quality education and is
described by the United Nations as “Obtaining a quality education is the foundation
to improving people’s lives and sustainable development” [57]. This project strives to
create a platform where knowledge can be more conveniently exchanged worldwide.
By providing professional literature, the quality of education will be improved, and the
mentioned goal will be achieved.
3.3 Ethical Aspects
There are some ethical implications to take into consideration while developing Lambå-
Atlas. This is due to the fact that the central part of the website is a 3D model of a human
body. What that body looks like with regard to skin color, gender and body type has to
be considered in terms of representation. Furthermore, when performing reconstructive
surgery, surgeons might sometimes have to choose between what looks “normal” and
how the “ideal body” looks [29].
3.3.1 Representation on the Main Page Human Body
Ethnicities, body shapes, and genders are some examples of what distinguishes different
human bodies, but since Lambå-Atlas only contains one human body, we must choose
which features our 3D model should have. Even though the appearance of the body
is not relevant for the practical part of the surgery [41], the ethical aspect of represen-
tation is relevant. In an optimal case, the user should be able to manipulate the body
and choose different features in order to represent all bodies, but this will not be imple-
mented since it is not the main focus of this project.
63 Purpose, Aims, and Motivation
Figure 2 The human body displayed on the main page of Lambå-Atlas
The human body on the main page of Lambå-Atlas is a gray and muscular 3D male
body as seen in Figure 2. The reason for the use of a gray skin tone is to avoid only
representing one ethnicity by using an unrealistic skin colour that represents all ethnic-
ities. The body has a lower than average fat percentage and even though this does not
represent the average person, it facilitates the work of the surgeons when the muscle
groups are easier to differentiate.
In the field of flap surgery, the difference between reconstructing a male body and a
female body is minimal [41]. Therefore, having two different human models, one for
each sex, would be superfluous from a practical perspective. The literature of medicine
tends to present the male body as the norm [37] and in order to counteract the poor
representation of the females in medicine, the group intended to use a female body.
However, this was not implemented since the group could not find any free 3D models
of a human body that fulfilled all features of being gray, muscular, and female.
73 Purpose, Aims, and Motivation
3.3.2 Pictures from Previous Surgeries
In addition to the 3D human body on the main page, Lambå-Atlas will contain images
from old surgeries, and the representation in those images are also relevant from an
ethical perspective. All images in the database of Lambå-Atlas will be uploaded by
Uppsala University Hospital, and this could result in a poor demographic representation.
In order to avoid poor representation, it is beneficial to have multiple users, in different
parts of the world, that can upload images to the Lambå-Atlas database. This is a feature
that could be added to Lambå-Atlas in the future.
3.3.3 Functionally over Appearance
The purpose with flap surgery is to reconstruct parts of the human body back to “nor-
mal”. Since Lambå-Atlas gives instructions about how this reconstruction should be
done and how the human body should look after the surgery, it will decide what the
“normal” human body looks like. These are ethical aspects that must be reflected upon.
The ideal body is something that also varies over time and varies in different coun-
tries [48], which also means that good representation is relevant.
When a body part undergoes flap surgery, both the functionality and the appearance of
the body need to be reconstructed. The importance of the appearance after the surgery
differs from case to case, since maintaining functionality is a priority. Every individual
user of Lambå-Atlas has different conditions, qualifications and financial preconditions.
To satisfy a variety of users, Lambå-Atlas needs to give more than one solution to each
surgical problem. When displaying multiple surgeries, the order in which the surgi-
cal suggestions appear will also affect what Lambå-Atlas defines as normal. To create
a system where this is determined by the users, rather than the creators, the surgical
suggestions will be sorted according to their average ratings given by the users which
describe how helpful the information has been.
3.4 Delimitations
Before starting development, some delimitations had to be made. An initial idea for the
3D body was that clicking on a body part would zoom in on that body part, revealing
even smaller clickable body parts. This became a delimitation due to the following
reasons. The first reason is that the user would already able to zoom freely on the body,
making it redundant to have an on-click zoom. The second reason is that dividing body
parts into smaller components results in difficult navigation of the 3D body. The final
84 Related Work
reason is that some small body parts would not require their own set of instructions.
Another delimitation is that a female body was not implemented due to the lack of free
3D models of a female body that met the other requirements of having an unrealistic
skin tone and being muscular. The current male 3D body that is implemented was not
designed by the members of this project, meaning that ethical problems that were in-
tended to be avoided, may exist. These implications are previously discussed in Section
3.3.1.
4 Related Work
There are programs that solve similar problems to Lambå-Atlas, but do it differently or
only a part of the problem this project aims to solve. Below, some related works are
discussed and how their purpose, functionality, or design relates to Lambå-Atlas.
4.1 Similar Purpose and Functionality to Lambå-Atlas
There are programs with similar purpose and functionality to Lambå-Atlas. There are,
however, differences between the programs that set the programs apart. What these
programs are and how they differ from Lambå-Atlas will be discussed in this section.
4.1.1 Microsurgeon.org
A similar program to Lambå-Atlas is the website microsurgeon.org [26], whose goal
is to “provide educational material relevant to microsurgery and reconstructive plastic
surgery” [27]. Microsurgeon.org provides texts, and illustrations on microsurgery for
educational purposes, as well as video lectures, showing how to perform microsurgery.
Their filter function is implemented as a list with different types of flaps for micro-
surgery, such as “head and neck” and “chest and back” [26]. In practice, this filter
function is similar to the one on Lambå-Atlas, although Lambå-Atlas uses a visual filter
in the form of a 3D body.
While microsurgeon.org provides information about microsurgeries, the information is
more theoretical than practical. This is one point where this site and Lambå-Atlas differ.
The general purpose of the two programs is similar, which is to educate on microsurgery
and reconstructive plastic surgery, although Lambå-Atlas strides to make an impact in
developing countries.
95 Method
4.1.2 Touch Surgery: Surgical Videos
Touch Surgery: Surgical Videos [31] is an app for learning or preparing for surgical
procedures. It includes surgeries for reconstructive plastic surgeries as well as for other
types of surgeries. These surgeries are presented using videos or simulations, illustrating
how to perform the procedure. For each surgery, background information is given, as
well as who authored the video/simulation. The different surgeries can be filtered using
broad terms, such as ”Plastic, Reconstructive and Aesthetic Surgery”.
This app provides similar information as Lambå-Atlas, and has a larger database of
surgeries. Lambå-Atlas however, has a different filter function using a 3D-body, which
is a more specific filter, making it easier to find the correct surgery.
4.2 Similar Design to Lambå-Atlas
ZygoteBody [61] is a website that renders a 3D human body. The website, created by
Zygote Media Group, has a similar front-end experience as Lambå-Atlas. Displaying
a 3D body with different types of functionality, e.g., zooming, rotating and selecting
body parts, is the main point of both ZygoteBody and Lambå-Atlas. ZygoteBody gives
the ability to view the anatomy of the body in different layers, a feature that would be
beneficial to Lambå-Atlas as well. The main differentiator between the two platforms
being the ability to get related information from the 3D body directly on the website.
5 Method
This section will present the methods used to design and create the website. Lambå-
Atlas is written in React and in order to display 3D graphics the library Three.js is used.
The relational database management system SQLite is used to store the surgeries and
lastly the framework Django is used to create the back end and API for Lambå-Atlas.
The reason these packages and frameworks were chosen and which alternatives that
could have been used will be discussed.
5.1 Choice of Software Platform
Accessibility is an essential part of Lambå-Atlas because a goal of this project is that
it should be accessible by surgeons all around the world. Therefore, a website that is
105 Method
accessible from mobiles phones, tablets, and desktops has been developed. The reason
behind why the website needs to be mobile friendly is because, in general, the access to
desktops is more limited than the access to mobile phones [53]. An alternative would be
to create a mobile application for both Android and iOS devices, but since mobile appli-
cations are only accessible on mobile phones, the latter was chosen. Another alternative
would be to create Lambå-Atlas as a desktop application, making it for desktop users
only, but this idea was eliminated since a website is accessible from a wider scheme of
devices than just desktops.
5.2 Designing a Prototype in Figma
The prototype for the project was created with the help of an interface design website
called Figma [33]. Figma is free to use and users can design prototypes for different
types of user interfaces. With the help of this website, the prototypes seen in Figure
3 and Figure 4 were designed. The reason for not choosing other design tools, such
as Sketch [50] or Adobe XD [24], is mainly because of Figma’s real-time collabora-
tion feature. This feature enables for different users to edit the same design and thus
made it easier to edit and give feedback on the prototypes. Another reason for favoring
Figma over Sketch and Adobe XD is that Figma can be used both as a website and a
desktop application, whereas the others can only be used as desktop applications. This
makes Figma more flexible, as it can be accessed using only a browser and an internet
connection.
115 Method
Figure 3 Figma prototype of the page where the user has chosen a body part and is
shown the 3D-model with a list of surgeries
Figure 4 Figma prototype of the page where the user has chosen a surgery and is shown
the 3D-model with surgical instructions
125 Method
5.3 Front-end Programming Language
The programming language for the front end had to be chosen to simplify the integration
of 3D graphics on a website. With this in mind, JavaScript was chosen, due to its versa-
tility and extensive list of libraries. It is used by 97.9% of all websites, where Google,
Amazon, and Facebook are some of the most popular ones [46]. Other alternatives
to JavaScript such as TypeScript [22] and CoffeeScript [6] are usually transcompiled,
meaning that the source code is compiled by translating a programming language to
JavaScript. While these languages may have their own benefits, such as improving error
management or readability, they are not as widely used and well-known as JavaScript
and thus offer less documentation online [40].
5.4 JavaScript Libraries
The 3D library Three.js was used for the implementation of the 3D model. Three.js
uses WebGL to draw 3D. WebGL is a low-level system that only draws points, lines,
and triangles, which therefore requires a lot of code to create a detailed object. Three.js
simplifies this process by handling scenes, lights, materials, and other components that
would have to be coded manually if WebGL was to be used directly [21].
React is another well-known library that was used for building the user interface. The
library offers resources that provide a responsive user interface and reduce develop-
ment time by having reusable components [45]. The combination of Three.js and React
allows for the usage of other available libraries and renderers.
React Three Fiber was used as a React renderer for Three.js [17]. Its task is to man-
age how the code components, which form the React tree, turn into the underlying
platform calls [5]. The renderer allows for a scene to be built with re-usable and self-
contained components, with no limitations on Three.js regarding functionality or perfor-
mance [17]. React Three Drei is an API made for React Three Fiber and the former was
used to control components such as cameras and controls for customizing a scene [18].
5.5 Handling 3D Objects
Lambå-Atlas uses the file format GLB to store the 3D objects and the software program
Blender to modify the 3D model. This segment discusses GLB and Blender, as well as
alternatives to them. File formats that fills a similar purpose as GLB are STL and OBJ
while Vectary and Wings 3D are software programs similar to Blender.
135 Method
5.5.1 3D-file Formats
There are different ways of storing information of a 3D-object. One of the alternatives
is STL, coming from stereolithogoraphy, and is one of the predominant file formats,
mostly used in 3D printing [47]. STL files build the object using triangular geometry,
which is the most basic way of creating meshes. STL files can be encoded with both
ASCII and binary representation, where binary is more compact and more used than
the ASCII counterpart. STL files cannot encode color information and lack support for
different materials in the same object [47].
OBJ is also one of the dominating file formats, created for the Advanced Visualizer
3D software in the 1980s [38]. With OBJ files, the objects can use meshes built up by
polygons. OBJ is widely supported and has the ability to store both color and texture,
but does this using a separate MTL (Material Template Library) file. OBJ files are slow
and inefficient due to a big file-size. Another drawback is that OBJ has not been updated
since it was launched in the 80s [38].
The file format GLB generate one of the smallest file-formats and is a further devel-
opment of GLTF (Graphics Language Transmission Format). The difference between
these are that GLB is encoded in binary, while GLTF is based on JSON [23]. This makes
the GLB file around 33% smaller than the GLTF option. GLB files are, with the small
file size, optimized for web and mobile applications. The main reason why GLB was
used is due to the small file size but while this is a strength, it is also a drawback. To
achieve this small file size, the file may not have the detail or material complexity for
larger, complex objects [1] [23].
5.5.2 Modifying 3D Objects
Vectary [59] is a simple to use, browser based, 3D modeling software available on most
browsers. The biggest strength of Vectary is that it is browser based, that means that
there is no installation of software needed. Being browser based also means that the
performance is limited and that some features available in other software programs are
not found in Vectary [35].
Wings 3D [60] is an open source, free to use, mesh modeler. A mesh modeler is showing
the vertices making up the 3D object. Being around since 2001, Wings 3D has built up
a large community of users, leading to many easy to find tutorials of how to use the
software [35].
Blender [55] is, like Wings 3D, an open source, free to use, mesh modeler, but also a
3D-modeling and animation program. Blender is not only used to create 3D objects, but
145 Method
can also be used to create animated movies. The biggest strength of Blender is how big
the user base is and this was the main reason why Blender was chosen. Blenders subred-
dit [4], a popular discussion forum, has more than three times the users of the second-
biggest 3D modeling software. Because Blenders large list of features, the learning
curve can be greater than the other alternative discussed [35].
5.6 Building the Back End
For building the back end, Django [7] is used. Django is an open-source web framework
in Python [16] used to ease the process of building programs, minimizing repeating
code. Using Django it is possible to design and implement the database, as well as
implement CRUD (Create, Read, Update, Delete) operations using the same code base,
which makes development faster, by reuse of code. Furthermore, Django comes with
built-in security features [19]. Secure password management is one built-in security
feature in Django [14], which makes development easier as there is one less thing to
worry about when developing the back end.
An alternative to Django, which is also written in Python, is the framework Flask [9].
Essentially, the things done in Django could be done using Flask. However, there are a
few key advantages to choosing Django. Firstly, it has a larger community, which makes
finding solutions to problems easier, as there are probably others who have had the same
issue before. Secondly, it has more features built-in, such as security features and a built-
in ORM (object-relational mapper) [42], which converts data from relational databases
to objects [28]. Lastly, unlike Flask, Django is a full-stack framework, with a built-in
admin page from which the database can be directly manipulated. Using packages, the
first two of these things could be done using Flask. Even so, Django was chosen due to
it having these features built-in, as well as providing an admin page, resulting in saving
time while developing Lambå-Atlas.
In addition to Django, the Django REST framework (DRF) [8], which is a toolkit built
on top of Django, is used to build the API (Application Program Interface) [2] of the
system. REST (Representational state transfer) [36] is a software architectural style that
defines how data transmission should be designed. The API is the part that handles the
communication between the front end and the back end. DRF is not necessarily needed
to build an API using Django, but it makes it easier and faster than building it from
scratch.
156 System Structure
5.7 Choice of Database
Regarding the choice of database program, the first question is whether a relational or
non-relational database is more suitable for our project. The database will mainly be
used for uploading new reconstructive surgeries and querying existing surgeries based
on attributes such as body part, ratings, and level of difficulty. In order to give a fast ex-
perience for the users, the performance while querying surgeries will be more important
than the performance while uploading new surgeries. Since relation databases perform
faster when querying non-key attributes [44] such as body part, ratings and difficulty,
the relational database SQLite [20] is used.
Apart from SQLite, Django officially supports four other relational database programs
and these are MariaDB [10], MySQL [11], Oracle Database [13], and PostgreSQL [15].
There are other databases that are supported using third party software, but to ensure
compatibility, one of the officially supported databases was chosen. Since the surgeries
are stored as PDFs the size of the database is small and will not exceed a few gigabytes
of storage. SQLite is such a small database that it makes the system fast, simply by
reducing the size of the database, and having less data to work with [49].
6 System Structure
Figure 5 An overview of the system structure. It illustrates how the different parts of
the system communicate with each other.
The system of Lambå-Atlas includes a back end and a front end. In the back end, the
database is built using SQLite and the server is built using Django with a REST API
166 System Structure
toolkit (Django REST framework). In the front end, React is used to build the client
site, where Three.js is used to render the 3D body, and the admin site is built using
Django. The client site gets data from the database through the server by making HTTP
requests to a REST API, as seen in Figure 5. The server then queries the database and
sends the data to the website.
6.1 Admin and Client Site
The front end consists of two different views. One is the client site, which is the website
that contains the 3D body. The other view is the admin site, which is a website where
the admins can overview, and manipulate, the content of the client site. The two sites
have separate code bases, where the client site is written using JavaScript and React
while the admin site is created using Python and Django.
6.1.1 Admin Site
The admin view is a pre-existing part of Django, which includes a login page and a
page where the admin can manipulate the database, see Appendix A. The admin site
could have been created using the same code base as the client site. However, as Django
already had an admin site ready to be used, it was decided to use it as it allowed for
more focus to be put on the client website.
6.2 CRUD and User Permissions
To manage and access the database, CRUD (CREATE, READ, UPDATE and DELETE)
operations are implemented. There are three different users in the system: users, ad-
mins, and superusers. The users can READ information about operations and reviews,
and can CREATE, UPDATE, and DELETE their own reviews on each operation. The
admins can do everything the users can, as well as CREATE, UPDATE, and DELETE
operations. They can also CREATE new users and DELETE reviews. The superuser
has every access and can therefore manipulate the whole database.
6.3 Communication Between the Front End and Back End
The front end communicates with the back end using the Django REST framework
through HTTP (Hypertext Transfer Protocol) [39] requests. HTTP is a communication
177 Requirements and Evaluation Methods
protocol used for transmitting data over the internet. HTTP requests are used are to
implement CRUD operations. GET, POST, PUT, DELETE, and PATCH are the HTTP
requests used in this system. The function of these are the same as their verbs. GET is
used to read information, POST is used to create, PUT and PATCH are used to update
information, and DELETE is used to delete information.
In order to check a user’s permission to make HTTP requests, token authentication is
used. The authentication token contains information about the user and enables them to
access the website without having to log in each time they visit the website [34]. This
token is included in the HTTP header, which means that it is included in every HTTP
request, regardless of the type of HTTP request transmitted.
6.4 Server and Database Communication
The database, SQLite, is a relational database. In this system, the database is constructed
by Django using an ORM, which, in this case, means that the only interaction with the
database is with Django. The ORM translates objects in Python into data that can be
stored in the database.
7 Requirements and Evaluation Methods
This section explains the users test that were implemented in order to test the website’s
functionality and usability. Furthermore, an evaluation will be presented based on the
results of the tests.
7.1 User Tests
User tests were carried out where reconstructive surgeons in Uppsala University Hos-
pital were asked to complete certain tasks on the website. These tasks consisted of
navigating the 3D-body, clicking on a specific body part and finding the right informa-
tion. The tests were performed to study the user experience and the website’s usability.
After completing the tests, the surgeons were asked to fill in a survey where they could
share their opinions, answer five questions, and rate the website’s functionalities on
scales ranging from one to five. An evaluation was then made by studying the surveys.
The test and survey are found in Appendix B.
Ethical implications must be considered, since the test and survey were only done by
188 Implementation of the 3D Model
reconstructive surgeons from Uppsala University Hospital. Therefore, the opinions that
were gathered from the survey could be skewed due to a lack of diversity of test subjects.
However, since there is a collaboration between reconstructive surgeons from Uppsala
and other countries, they can arrange for other surgeons to take part in the same test and
survey, which is further discussed in Section 10.
7.2 Evaluation of User Tests
The questions in the survey were answered on a scale from one to five, where a rat-
ing of at least three meant that the respective functionality is sufficient for its purpose.
Therefore, if the functionalities received average ratings of at least 3, they are deemed
successfully developed and thus user-friendly.
The results from the survey showed that the average ratings for the functionalities was
a 4.5 which is thus deemed successful. The lowest average rating was received in the
question where the user was asked to rate the website’s aesthetics. The average rating
for that question was a 3.7, which is also considered successful. 89% of surgeons an-
swered that they would recommend the website to other reconstructive surgeons. Other
opinions were also given by the surgeons, mostly revolving around the lack of surgical
information and the possible ways of displaying it. Some of these opinions can be used
for future work and are further discussed in Section 10. Graphs displaying the exact
results of the surveys can be seen in Appendix C.
8 Implementation of the 3D Model
This section provides an in-depth description of the implementation of the 3D model.
Procedures such as dividing and importing the body are explained.
8.1 Dividing the 3D Body Into Body Parts
An OBJ file is a standard 3D image format that can be exported or imported by several
3D image editing programs such as Blender or Tinkercad [12]. These files can be con-
verted to another format known as GLB, which also stores 3D objects [1]. When a file
is acquired in GLB format, it is possible to run a command which produces a JavaScript
file that contains code for importing the 3D object onto a project. The command is
run through npm which is a critical part of JavaScript and, among other things, a com-
198 Implementation of the 3D Model
mand line client that allows developers to install packages of open-source code [3]. By
correctly dividing the 3D body in the 3D image editing programs, the conversion to
a JavaScript file will include all body parts as code, consequently allowing for simple
manipulation of the body parts.
8.2 3D-modeling Software
The free and open source software Blender [55] was used to create the divided 3D body.
The GLB file is structured such that it contains several objects within a larger file. In
Figure 6 the different objects are displayed with orange outlines inside Blender. With
Blender, the bisect tool was used to divide the 3D body and make the different body parts
to separate objects. Using Blender, the different body parts were also named directly in
the software.
209 Results and Discussions
Figure 6 Screenshot from Blender software displaying how the body parts were divided
9 Results and Discussions
This project resulted in a website that can help reconstructive surgeons in the planning
and execution of surgeries. The external supervisor of this project, Dr. Morten Kildal,
intends for the final website to be an aid for reconstructive surgeons by letting them
navigate a 3D human model and offer surgery instructions based on a chosen body part.
A reconstructive surgeon can, during the planning and execution of surgery, rotate and
zoom the 3D model, choose a body part and study the surgery instructions provided. By
doing this, the project aims to assist reconstructive surgeons around the world with an
intuitive platform which will simplify assessment of surgery. The collaboration that this
project’s stakeholder has with Tanzania, Ethiopia and Palestine, has influenced the aim
2110 Future Work
that Lambå-Atlas has to contain and sort information based on experience and medical
equipment. To realize this aim, all surgical instructions have been labelled and sorted
by difficulty and medical equipment required.
In order to evaluate the user experience of the website, user tests were carried out on
reconstructive surgeons. After testing the website, the surgeons took part in a survey
where they could rate the functionalities and express their opinions about the website.
The results of the surveys revealed that the majority of the surgeons found the website
to be practical and helpful. A large majority of the surgeons would also recommend the
Lambå-Atlas website to other reconstructive surgeons. The exact results of the survey
are discussed in Section 7 and graphs for the results can be found in Appendix C.
10 Future Work
The desired functionalities for the website were initially many, but were through the
course of the project reduced and put into future works. This section will further present
these and explain why these were not implemented.
10.1 Local Data Storage
The use of local data storage was discussed early in development. This is due to the data
limitations in developing countries where Lambå-Atlas could be used. However, the
focus was instead prioritized on design and functionalities. The external supervisor Dr.
Morten Kildal also influenced the choice of a website by sharing his personal experience
in those developing countries. Dr. Kildal explained that the surgeons in those countries
had access to the internet at most times and places, thus a website would be sufficient.
Another reasoning for not storing data locally is that the data consists of PDF-files
that are miniscule in size. In the future, Lambå-Atlas may contain larger files or be
used in areas where the internet connection is worse than what Dr. Kildal experienced.
Therefore, it is worth considering storing data locally if the website was to receive more
users.
10.2 Storing Patient Information
A future development for Lambå-Atlas could be a feature for surgeons to create and
save data from previous patients on their profiles. An idea for this would be to save
22References
a patient’s name along with a description, pictures of the surgery, and which surgical
instructions that were chosen on the website. By implementing this, they could at any
time revisit past surgeries to evaluate which surgical methods that were superior and use
that information for future surgeries.
11 Conclusions
Overall, Lambå-Atlas is a new interactive way for reconstructive surgeons to tackle
the problem of finding relevant information about what surgery, or procedure to use
on a patient. Furthermore, the ability for surgeons to rank procedures can assist future
surgeons with choosing the appropriate procedure. The available information also gives
surgical teams an easy way of comparing different operations.
One of the main goals of the project was to create a platform that would promote knowl-
edge exchange and education for reconstructive surgeons. By providing a platform
where surgical instructions —from where knowledge and education can be gained—
are accessible, this goal has been fulfilled.
The purpose of making a platform accessible to countries that do not have the possibility
to search through big medical databases, has been an integral part of this project. The
collaboration with this project’s stakeholder, The University Hospital in Uppsala, has
made it possible for Lambå-Atlas to reach countries such as Tanzania, Ethiopia, and
Palestine and provide their surgeons with the knowledge platform. There are benefits of
introducing a platform for knowledge exchange in order to further develop the area of
reconstructive surgery. Another aspect towards the development of the area is the usage
of a platform as Lambå-Atlas in countries where injuries caused by war and industry
are prevalent. Because of the complexity and uniqueness of such injuries, the area of
reconstructive surgery will evolve. The external supervisor of this project, Dr. Morten
Kildal, has been, in the light of the current war between Russia and Ukraine, working
with surgeons in Ukraine, educating them about reconstructive surgery. This is a prime
example of a situation where the functionality of Lambå-Atlas could be used, and thus
developing the area of reconstructive surgery.
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