SRS.dvi
Software Requirements Specification
Team Aura
Virtual Surgery
April 7, 2011 Revision : 2.0
Abstract
This Software Requirements Specification (SRS) specifies the requirements
for the system produced by this project. Firstly, this document contains back-
ground information on temporal bone surgery, including the surgical proce-
dures and tools used, and an overview of the existing system.
Secondly, the SRS outlines the proposed system to be developed. The
proposed system is detailed in terms of functional and non-functional require-
ments. The document also provides examples of behaviour of the system and
prototypes (guides) for the graphical user interface.
Contents
1 Introduction 1
1.1 Overview of Project . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Scope of Document . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.3 Purpose of Document . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.4 Client Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.5 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 Background On Temporal Bone Surgery 3
2.1 Hazards and Landmarks in Surgery . . . . . . . . . . . . . . . . . . . 3
2.2 Types of Cavities to Drill . . . . . . . . . . . . . . . . . . . . . . . . 3
2.3 Tools Used in Drilling . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3 Existing System 5
3.1 CT scans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1.1 How CT Scans are Produced . . . . . . . . . . . . . . . . . . 5
3.1.2 Uses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.2 3D Modelling Software: AnalyzeAVW . . . . . . . . . . . . . . . . . 5
3.2.1 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.2.2 Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4 Proposed System 7
4.1 Core Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4.2 Non-Core Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 7
5 Functional Requirements 8
5.1 Core Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
5.1.1 Convert a CT Scan to a 3D Model . . . . . . . . . . . . . . . 8
5.1.2 View and rotate a 3D model . . . . . . . . . . . . . . . . . . 9
5.1.3 Interact with a 3D Model . . . . . . . . . . . . . . . . . . . . 9
5.2 Non-Core Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 10
5.2.1 Convert CT Scan to 3D Model . . . . . . . . . . . . . . . . . 10
5.2.2 View and rotate a 3D model . . . . . . . . . . . . . . . . . . 10
5.2.3 Interact with the 3D model . . . . . . . . . . . . . . . . . . . 11
5.2.4 Augment the CT scans . . . . . . . . . . . . . . . . . . . . . 12
6 Non-functional Requirements 14
6.1 Nature of Users . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
i
6.1.1 Users of the system . . . . . . . . . . . . . . . . . . . . . . . . 14
6.1.2 Hardware competence . . . . . . . . . . . . . . . . . . . . . . 14
6.1.3 Software competence . . . . . . . . . . . . . . . . . . . . . . . 14
6.2 User Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6.2.1 Setup Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.2.2 Reference and Troubleshooting Guide . . . . . . . . . . . . . 15
6.3 Hardware constraints . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.4 Performance requirements . . . . . . . . . . . . . . . . . . . . . . . . 16
6.5 Design Constraints . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.6 Implementation Constraints: Technical Resources . . . . . . . . . . . 16
6.7 External Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.8 Error handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.9 Software System Attributes . . . . . . . . . . . . . . . . . . . . . . . 17
6.9.1 Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.9.2 Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.9.3 Maintainability . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.9.4 Portability . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7 Graphical User Interface 18
7.1 Core Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7.1.1 3D Virtual Surgery Screen . . . . . . . . . . . . . . . . . . . . 18
7.2 Non-Core Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 20
7.2.1 3D Virtual Surgery Screen . . . . . . . . . . . . . . . . . . . . 20
7.2.2 Augment Screen — View One Slice . . . . . . . . . . . . . . . 21
7.2.3 Augment Screen — View Two Slices . . . . . . . . . . . . . . 23
8 Examples of Behaviour 25
8.1 Core Requirement Behaviour . . . . . . . . . . . . . . . . . . . . . . 25
8.2 Non-Core Requirement behaviour . . . . . . . . . . . . . . . . . . . . 25
8.2.1 Augment the CT scan . . . . . . . . . . . . . . . . . . . . . . 25
8.2.2 Perform the Virtual Surgery Operation . . . . . . . . . . . . 26
9 Product Acceptance Criteria 27
10 Delivery Plan 28
11 Glossary 29
12 Client Sign-off 31
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List of Figures
1 Photo of a 3 mm cutting burr . . . . . . . . . . . . . . . . . . . . . . 4
2 CT Scans sliced at 0.1 mm intervals . . . . . . . . . . . . . . . . . . 8
3 Size of one drill unit . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4 Path of a burr and portions of 3D models drilled . . . . . . . . . . . 11
5 3D Virtual Surgery Screen — Core . . . . . . . . . . . . . . . . . . . 19
6 3D Virtual Surgery Screen — Non Core . . . . . . . . . . . . . . . . 20
7 Augment — View One Slice . . . . . . . . . . . . . . . . . . . . . . . 22
8 Augment — View Two Slices . . . . . . . . . . . . . . . . . . . . . . 24
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1 Introduction
1.1 Overview of Project
The aim of this project is to create a software system which enables surgeons to
simulate temporal bone surgery. To create a Virtual Surgery environment, the
system displays the structure of the bone and enables the user to drill the bone.
The project does not deal with other aspects of surgery such as making the incision,
or closing up the wound of a patient.
The system can be divided into three sections:
1. Generation of a 3D model: Using data provided by CT scans, a 3D model is
created. Only a small section of the skull is represented for virtual surgery.
2. Simulation of Bone drilling: The surgeon interacts with the model, and per-
forms a virtual surgery.
3. Augment 3D model with landmarks: Allow surgeons to represent on the 3D
model where the landmarks exist.
1.2 Scope of Document
This document (Software Requirements Specification) provides background infor-
mation regarding the nature of the virtual surgery being simulated. Based on the
IEEE Software Engineering Standards, this document lists the functional require-
ments according the features of the system (a features structure — see IEEE. Std
830-1993 SRS A.5 Template).
The SRS also covers the non-functional requirements, including issues such as per-
formance constraints, hardware constraints, nature of users, external interfaces,
implementation requirements and the software system attributes. The document
prototypes of the graphical user interface, and some examples of behaviour for the
system.
1.3 Purpose of Document
The aim of this Software Requirements Specifications (SRS) is to list all of the
requirements that the final product must satisfy. The intended audience of this
document includes Team Aura, the project’s clients, and any software developers
who may be further developing this project in the future.
The aim of this document is to enable Team Aura and the clients to reach a com-
mon understanding of the software system to be built and the product acceptance
criteria. This document will also be used by the team in planning the system ar-
chitecture (Software Architecture Design Document) and developing the detailed
design (Software Design Document).
Finally, this document will also serve as a basis for further improvements on the
software in the coming years. This will include any of the non-core requirements,
and any other further technological developments.
1
1.4 Client Details
Omitted to preserve anonymity.
1.5 References
• “IEEE Standards Collections, Software Engineering”, 1997, The Institute of
Electrical and Electronic Engineers.
• S. Horiil. DICOM: An Introduction to the Standard
URL http://www.dicomanalyser.co.uk/html/dicom.htm Undated, fetched
6 May 2000.
• R. Robb, D. Hanson, M. Stacy and J. Camp. Biomedical Imaging Resource.
URL http://www.mayo.edu/bir/ Undated, fetched 6 May 2000.
• CancerWeb. The On-line Medical Dictionary.
URL http://www.graylab.ac.uk/omd/index.html Undated, fetched 6 May
2000.
2
2 Background On Temporal Bone Surgery
Temporal bone surgery refers to any surgical procedure involving the complex bone
situated around the side of the skull (near the temples).
The types of surgery which fall into this category include:
• Bionic ear implant surgery — drilling sufficient cavities to implant the bionic
ear package (further background available at the website:
http://www.medoto.unimelb.edu.au/cic/);
• Exploration of temporal bone for the removal of disease;
• Approaches to the skull base — methods of drilling the bone to reach the
brain.
2.1 Hazards and Landmarks in Surgery
When performing the bone removal procedure, there are certain landmarks surgeons
need to be aware of, and hazards they should avoid, when drilling.
Some key landmarks in temporal bone surgery include:
• Dura mater (including the sigmoid sinus, which is a localized area of the dura
mater);
• Facial nerve;
• Ossicles and the ear drum;
• Inner ear and internal auditory meatus.
For example, it is dangerous to penetrate the dura mater, as it will cause the brain
to be flooded with fluid (known as a CFS leak), and put the patient at risk of
meningitis.
2.2 Types of Cavities to Drill
During temporal bone surgery, cavities of different shapes and sizes may be drilled.
For example, a surgeon operating to implant the bionic ear would be required to
drill the following holes:
• Large cavity (shaped like a flowerpot, cone or pyramid) – starting wide from
the outer bone, and narrowing in as it gets closer to the inner ear
• Medium cavity connecting mastoid to the middle ear (posterior typamotomy)
• Very small cavity around 0.6 mm near the inner ear so that the electrode of
the bionic ear package can be inserted into the spaces in the cochlear
3
Figure 1: Photo of a 3 mm cutting burr
2.3 Tools Used in Drilling
The drilling tool consists of a “burr”, driven by an electric motor. The burr can
also be used manually. Refer to Figure 1 for a photo of a 3 mm cutting burr.
There are four properties related to the burr and its use:
1. Texture: There are two main types of burrs —
(a) Cutting burr (diamond head) — used to remove large parts of the bone;
(b) Polishing burr — used to remove small, finer parts of the bone.
2. Size: The burrs come with different sized heads. Different sized burrs (from
0.6 mm – 7 mm) are used to remove different quantities of bone. A larger
burr size would remove more quantities of bone.
3. Torque / Speed: By using a foot pedal, the surgeon can vary the rotating
speed of the burr. A faster speed would provide more torque, which removes
more quantities of bone.
4. Pressure: By placing more pressure on the burr, the surgeon can remove more
quantities of bone, provided there is sufficient torque
During the drilling process, bone fragments are created. A “surgical irrigator” runs
fluid through the area of bone being drilled, to ensure that bone fragments can be
easily removed by the sucker.
4
3 Existing System
This section provides an overview of the existing system. The clients currently have
aids which allow them to examine the temporal bone area. These include:
1. CT scans — provide 2 dimensional (2D) slices of the skull;
2. 3D modelling software: AnalyzeAVW — reconstructs 2D and 3D models of
the skull from the CT scans.
3.1 CT scans
CT scans are otherwise known as computed tomography, or computed axial tomog-
raphy scans.
3.1.1 How CT Scans are Produced
They are produced by a special radiographic technique which uses a computer to
assimilate multiple X-ray images into a 2D cross- sectional image. The machine
rotates around the patient’s body, sending out a pencil-thin X-ray beam at 160
different points to take an X-ray of the patient’s head.
This project will deal with CT scans that are sliced at intervals of 0.1 mm up to
2.0 mm. They can be sliced in an axial or coronal plane. The slices are presented
as a series of pictures on X-ray films, or saved into the DICOM file format.
3.1.2 Uses
Using the X-ray films, surgeons can examine the series of pictures and determine
the cavity (or cavities) that need to be made. They are used to identify variation in
the anatomy, pathology (areas of disease) and also to plan the surgical procedure.
The CT scans saved in DICOM file format is used by the existing software (see
below) to generate 3D models. They will also be used in this project as the source
of raw data from which 3D models are generated (See Section 4).
3.2 3D Modelling Software: AnalyzeAVW
AnalyzeAVW is a proprietary software used by surgeons and other medical profes-
sionals to model the anatomy of the head. The software uses the CT scans, saved
in DICOM file format, to reconstruct 2D and 3D models of the head.
3.2.1 Main Features
The main features of the software include:
1. Retrieval and management of image data from many file formats including
DICOM;
2. Generation and display of 2D and 3D images;
5
3. Image processing, registration and segmentation using image algebra (e.g. 3D
matrix operations and geometric transformations);
4. Selection and sampling of regions of interest (e.g. 3D model limited using a
threshold density of the head — narrow range of 220–240 represents dense
parts, wide range of 20–200 produces 3D model including most parts of the
head’s tissue);
5. Ancillary features including screen capture tools, editor for session notes, hard
copy printing of text, labels and graphics.
3.2.2 Limitations
The software does not allow a virtual surgery environment to be simulated. In
particular, the software is unable to:
1. Represent the actual cavity to be drilled;
2. Allow users to interact with the 3D model and simulate drilling;
3. Allow the landmarks and hazards marked in by the users to be represented in
the 3D model.
More information regarding this software may be located at the official website of
the AnalyzeAVW developers: http://www.mayo.edu/bir/.
6
4 Proposed System
The proposed system creates an environment to simulate temporal bone surgery.
The major element in the environment will be a 3D model of the skull obtained from
a CT scan. The system will enable users to interact with the 3D model to simulate
drilling during a surgical operation. It is intended that the virtual environment
will be used for teaching and training purposes for both trainee and experienced
surgeons.
The system to be developed is seen as the first stage in the development of a
sophisticated virtual surgery tool. To this end much of the development in this
stage will consist of research and prototyping to find the most effective and efficient
methods of implementing the 3D model and interactive tools.
The functionality of the proposed system has been divided into two sections, core
and non-core. This is due to the experimental nature of the project where the
feasibility of many of the requirements is dependent on the results of research and
prototyping.
4.1 Core Requirements
These are the essential requirements of the system which need to be implemented
before the product can be accepted. The requirements are described using the
features that the system must be able to offer a user.
1. Convert a CT scan to a 3D model;
2. View and rotate the 3D model;
3. Interact with the 3D model using an input device to drill away portions of the
3D model.
4.2 Non-Core Requirements
These requirements have been sourced from the clients as an indication of the fea-
tures they highly desire but are not necessary for the acceptance of the software.
After the core system has been built according to the requirements as detailed in
Section 4, the team will move on to develop these highly desirable features for the
system.
It is anticipated that at least some of these features will be able to be imple-
mented. It is also intended that some of these features will be extended or will
be implemented by future developers of the system. Below is an outline of which
requirements fall into the non-core requirements.
1. Extended functionality to view and rotate the 3D model;
2. Extended functionality to interact with the 3D model.
3. Augment the 3D Model with hazards (allow surgeons to represent on the 3D
model any hazards that my exist).
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5 Functional Requirements
5.1 Core Requirements
These are the essential requirements of the system which must be implemented
before the product can be accepted. The requirements are described using the
features that the system must be able to offer a user.
The following discusses each of the features in further detail.
5.1.1 Convert a CT Scan to a 3D Model
To convert the data provided by the CT scans into a 3D model, the system imple-
ments the following features:
1. Input Data Format — Read in CT scans provided in DICOM 3 format;
2. Input Data Resolution — Represent the 3D image using slices made at a
minimum of 0.5 mm intervals (refer to Figure 2);
Figure 2: CT Scans sliced at 0.1 mm intervals
3. Limited tissue — Limit the 3D model to representation of the bone only (no
other tissue such as veins, nerves, skin) where the density of the tissue to be
represented is provided by the client;
4. Limited volume — Automatically limit the 3D model to a small 40 mm x 40
mm x 40 mm region, which is the maximum amount of volume the surgeon will
deal with when performing temporal bone surgery (where the exact volume
to limit is provided by the client);
5. Resolution of 3D model — Represent the 3D model with a minimum resolution
of 1 voxel per 0.5 mm x 0.5 mm x 0.5 region.
6. CT Scan Threshold Control — Allow the user to control the thresholds of the
CT scan used to construct the 3D model.
8
5.1.2 View and rotate a 3D model
To enable the user to view a 3D model, the system implements the following features:
1. View — View the 3D model at a minimum size of 1 voxel corresponding to
0.5 mm x 0.5 mm x 0.5 mm region (original size);
2. Rotate — Rotating the 3D model in any direction required, where the rotation
need not be smooth or continuous, i.e. the screen need only represent the
rotated 3D model and not any other positions in between;
3. Zoom in — Zoom into the 3D model to view it closer, but the data is not
processed in any way to provide better resolution than the CT scans where a
high level of magnification may produce rough edges;
4. Zoom out — Zoom out of the 3D model to the original size;
5. Traverse — Traverse into the bone cavities, e.g. inside a cavity that has been
drilled by the user;
6. Save — Save the 3D model produced into a file format using a user specified
name.
Note that in this document, any reference to (or interaction with) the 3D model
refers to the model which represents the bone tissue of the CT scans, and not
any other items which may constitute part of the 3D model (such as empty space
surrounding the bone tissue).
5.1.3 Interact with a 3D Model
This is a critical part of this project. The system provides a virtual surgery en-
vironment where a user can drill away bone (portions of the 3D model) using an
input device. A solid volume of the bone (3D model) is eventually drilled away.
To enable the user to interact with the 3D model, the system implements the
following features:
1. Screen — Represents the 3D model on the screen, with the cursor moving on
the screen corresponding to the user’s movement of the input device;
2. Virtual Burr — Implements the mouse as an input device to simulate the
drilling tool (burr);
3. Virtual Burr Specifications — Models a 3mm burr where the volume drilled
away per drill is one drill unit. No other characteristics (or use) of a real burr
are implemented (e.g. texture, size, torque and pressure);
4. Drill Unit — Where one drill unit is 2.5 mm wide x 2.5 mm long x 1.0 mm
depth (refer to Figure 3 and Figure 4);
5. Screen Refresh — Updates the screen at a rate of at least 1 second per drill
unit removed;
6. Limited drilling area — Limits the drilling area to the 3D model — and
placing the cursor at any other points on the screen will not cause the screen
to refresh or perform any action;
9
Figure 3: Size of one drill unit
7. Sense of depth — Represents a sense of depth;
8. Saving — Saves the 3D model resulting from the interaction into a file format
using a user specified filename. Allows 3D model to be loaded and viewed as
per Section 4.1.2. and interacted with as per Section 4.1.3;
9. Bone fragment removal — Assumes when the bone is drilled, the bone disap-
pears. Does not represent the surgical irrigator and the sucker’s removal of
the bone fragments.
5.2 Non-Core Requirements
These requirements have been sourced from the clients as an indication of the fea-
tures they highly desire but are not necessary for acceptance of the software.
5.2.1 Convert CT Scan to 3D Model
In addition to the features described in Section 4.1.1, the non-core system includes
the following features —
1. Input Data Resolution — Represent the 3D image using slices made at 0.1
mm intervals (refer to Figure 2);
2. Input Data Resolution — Represent the 3D image using slices made at per
0.033 mm intervals (3 slices per 0.1 interval);
3. Resolution of 3D model — Represent the 3D model with a minimum resolution
of 1 voxel per 0.1 mm x 0.1 mm x 0.1 region.
5.2.2 View and rotate a 3D model
In addition to the features described in Section 4.1.2, the non-core system includes
the following features –
10
Figure 4: Path of a burr and portions of 3D models drilled
1. Zoom in — Zoom in and view the 3D model at magnifications of:
(a) 1000% ( x10 )
(b) 2000% ( x20 )
(c) 3000% ( x30 )
where the image still appears smooth and continuous (not pixelated) at the
maximum magnification;
2. Densities — View bone of two varying densities: honeycomb or hard, where
the amount of removed by the drill is proportional to the density of the bone
and the densities are provided by the client;
3. Translucent 3D model — Generates a translucent 3D model, such that the
inner parts of the 3D model can be viewed from the outside;
4. Illumination — Allows the 3D model to be viewed as if the 3D model is
illuminated by different light sources from various points.
5.2.3 Interact with the 3D model
In addition to the features described in Section 4.1.3, the non-core system offers the
following features to users –
1. Virtual Burr
(a) Texture of burr — Represents two different burr textures including:
i. a diamond polishing burr; and
ii. a cutting burr;
where each tool produces a different effect when used to drill away por-
tions of the 3D model where the effects of the tools are specified by the
clients;
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(b) Size — Provides different sizes of burrs ranging from 0.6 mm to 7 mm
where the size of the burr affects the size of the drilling unit (refer to
Section 4.1.3) and portion of the 3D model removed where the effects of
the sizes are specified by the clients.
(c) Torque or Speed — Select the speed at which the burr is rotating (sim-
ulation of the foot pedal) – which is from 0 — 6,000 revs/sec where the
effect of the speed is specified by the clients;
(d) Pressure — Simulates pressure by using the amount of pressure the user
places on the input device, affecting the number of units of the 3D model
being drilled, where the quantitative effect of the pressure is specified by
the clients.
2. Removal of bone
(a) Fast screen refresh (10 frames / sec) — The screen refreshes at a rate
of 10 frames per second, to allow minimum lag time and a smooth and
continuous drilling process (i.e. surgeon is able to instantaneously see
the effects of the burr on the 3D model);
(b) Auditory response with the burr — The system produces a sound which
is similar to the sound produced by real burrs when drilling. The sound
varies depending on:
i. whether the burr is in contact with the 3D model;
ii. the amount of pressure on the bone when the bone is being drilled;
iii. the density of the bone of the bone being drilled;
iv. the thickness of the bone of the bone being drilled.
The effects of the above factors on the sound are specified by the client.
3. AutoSave — The system will automatically save the changes made by the user
in drilling the bone at a regular time interval as specified by the user.
5.2.4 Augment the CT scans
This is a new feature not previously detailed in the core system. The 3D model
created by the core system only includes the bone structure. This feature enables
the user to augment the CT scans with other types of tissue or landmarks (refer to
Section 2) which the user needs to be aware of and possibly avoid when drilling the
bone.
As there are currently other packages which will allow users to augment the CT
scans, the client feels that this requirement is of low priority.
The representation of the landmarks involves the following process (and the features
offered by the system to facilitate each step):
1. Represent the CT scans as 2D slices on the screen
(a) View one slice — View each of the 2D slices separately where each slice
closely represents the CT scan slices as viewed by surgeons on an X-ray;
(b) View two slices — View an unmarked 2D slice placed on top a marked
2D slice so that the latter can be used as a guide for the former.
2. User marks all or some of the 2D slices using the tools provided
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(a) Drawing tools — Provides tools such as paint brushes, marquee tools,
pens, straight lines, paint buckets to enable the user to mark any 2D
shape on a CT scan slice;
(b) Colour Palette — Select from a colour palette of up to 24 colours;
(c) Limitation of colour — Each landmark can only be marked in one colour,
e.g. the Dura Mater may be represented by red, and the sigmoid sinus
in green.
3. Marked 2D slices are converted into a 3D model
(a) Join landmarks in slices — The user may choose to mark some or all of
the slices. If not all slices are marked, the system joins up the marked
regions as a straight line to fill in the missing gap where some slices have
not been marked;
(b) Generate 3D model — A 3D model with the original CT scan data and
the newly added landmarks is produced;
(c) Save — Save the 3D model generated into a file format with a user
specified filename, which can be loaded to be viewed as per Section 4.1.2
and interacted with as per Section 4.1.3.
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6 Non-functional Requirements
6.1 Nature of Users
The following section details the nature of the users of the software, including their
level of technical expertise and purpose for using the software.
6.1.1 Users of the system
1. Trainee surgeons
• To plan and practise temporal bone surgical procedures;
• To gain an understanding of the bone structure and drilling process by
viewing the 3D model and the sample cavities drilled by the experienced
surgeons.
2. Experienced surgeons
• To perform Virtual Surgery for as a rehearsal for the management of an
unusual problem;
• To augment the CT scans with appropriate landmarks for the benefit of
trainee surgeons;
• To drill different types of cavities as samples for trainee surgeons;
• To replay sections of performed surgery for analysis.
3. Diagnostic Personnel (e.g. radiologists) — may find it useful to use the soft-
ware as a tool for examining the bone structure and CT scans of a patient;
4. Matching information acquired from X-rays and magnetic reasonance imaging.
6.1.2 Hardware competence
The users will have some basic computer knowledge, including the use of hardware
such as mouse and keyboard. Any non-standard hardware (especially Virtual Re-
ality Tools) will be accompanied with appropriate training material to allow users
to adapt to them quickly and effectively.
6.1.3 Software competence
The users will be familiar with Windows 98 and the basic functions such as opening
an application and closing an application. The software shall be sufficiently user
friendly to allow users with basic computer literacy to use the basic functions of
the software effectively. There shall be accompanying documentation to assist users
with using the more advanced functions of the software (refer to Section 5.2 below).
6.2 User Documentation
Documentation will be supplied with the final software product. The user docu-
mentation shall specify and describe the required data and control inputs, input
sequences, options, program limitations, and other activities or items necessary for
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successful execution of the software. All error messages will be clear and appropriate
corrective actions described.
There will be two user documentation produced: a brief Setup guide, and a complete
Reference and Troubleshooting Guide.
6.2.1 Setup Guide
Target Audience: Users of the software.
Purpose: A brief guide to assist users with the technical aspects setting up the
custom software provided.
Contents: The contents shall include —
1. Instructions for installing and setting up the custom software;
2. Instructions for setting up and configuring the associated hardware.
3. Explanation for the specification of each of the burrs and an explanation for
the limits of resolution and torque.
6.2.2 Reference and Troubleshooting Guide
Target Audience: Users of the software.
Purpose: A reference guide for users of the software to use and understand the
functionality of th