Surgical Navigation - insights into wayfinding and navigation processes in the human body

Cognitive ergonomics for minimally
invasive therapies – some insights into
wayfinding and navigation processes in
the human body
Position
Thomas Stüdeli
14 December 2009
Farewell lecture Thomas Stüdeli
Faculty of Industrial Design Engineering
Delft University of Technology
Position
Destination
References and
Obstacles
New course

Thomas Stüdeli Ergonomics, Human Factors, Safety Engineering
Delft University of Technology, Faculty of Industrial Design Engineering
Medisign group – Research and
Product development in healthcare,
e.g. “Surgical cockpit”
www.io.tudelft.nl/medisign
Human Information
Communication Design
Intelligent products, ambient
intelligence, perception, information
processing and information design
“Augmented Reality in Surgery” (FP6,
2004-2008), AR/VR-Systems for
Thomas Stüdeli
14 December 2009
2004-2008), AR/VR-Systems for
surgery and intervention radiology
www.ariser.info
[Lamata 2007]
[Mühl 2007]

ARIS*ER www.ariser.info
• “Augmented Reality for Surgery”, FP6 programme, 2005-2008
• Six academic and two industrial partners, app. 40 involved
researchers
Thomas Stüdeli
14 December 2009

Augmented Reality in Surgery
(ARIS*ER) - Laparoscopy
Thomas Stüdeli
14 December 2009
Augmented
laparoscopic images
(liver resection)
Lack of haptic
feedback and limited
orientation
performance in
laparoscopic images

Augmented Reality in Surgery
(ARIS*ER) – Robotic surgery
Augmented robotic arms
(robotic surgery)
Collisions of robotic arms outside
the field of view of the surgeons
Thomas Stüdeli
14 December 2009

Augmented Reality in Surgery (ARIS*ER) –
Intervention radiology
Thomas Stüdeli
14 December 2009
How to visualize relevant
anatomical information for (safe
and efficient) abdominal needle
placements?
Augmented needle trajectory
line – 2D image & 3D map

Minimally invasive cardiac surgery
Keywords: Team work, Complex
operation, Cardio pulmonary
bypass, Time-critical, Patients
safety
Human factors: Safety, Efficiency,
Quality
Thomas Stüdeli
14 December 2009
Catheter positioning
system
Annuloplasty ring
solution
[Graduation Project
Felipe Morales 2009]
[ARIS*ER cardiac project
2006-2008]

What could be an “intelligent” User Interface?
(Exp. Needle placement)
Thomas Stüdeli
14 December 2009
[Laban, Korteland, Boudri & Stüdeli 2008]

Agenda
• Motivation (ergonomic viewpoint)
– Minimally invasive Surgery
– Design of navigation support
• Navigation and wayfinding processes
(safe and prudent)
Thomas Stüdeli
14 December 2009
(safe and prudent)
– Orientation, Navigation Wayfinding
• Latest research
– Role of information modalities (visual,
haptic, mental model)
• Outlook

Operation theater – a special work environment
Thomas Stüdeli
14 December 2009
• Individual AND team work
• High time pressure AND high demands
• Action tasks AND monitoring / control
tasks
• Highly complex AND highly regulated
“Entering an Operation Theater, it’s
like going 100 years back in
Ergonomics” Richard Goossens
(10.8.2009 Beijing)

Thomas Stüdeli
14 December 2009

Motivation
• Importance: Computer systems, visualization techniques,
and robotic technology aim to enable and/or support
surgical actions. Navigation is obviously one essential
action.
• Definition: “Surgical navigation” has not generally been
well defined and therefore has been used inconsistently.
It’s essential for communication in between
multidisciplinary teams to be aware of those different foci
Thomas Stüdeli
14 December 2009
multidisciplinary teams to be aware of those different foci
and usages of key words.
• Aims:
– Know-how transfer: The aim is to translate know-how from
cognitive models of navigation and wayfinding into the field of
surgical navigation.
– Support: The ultimate aim is to contribute to the design of more
intuitive and more effective information and navigation system
for the medical domain.

Agenda
• Navigation and wayfinding
processes (safe and prudent)
Thomas Stüdeli
14 December 2009
processes (safe and prudent)
• Latest research
• Outlook

Classical (maritime) navigation
Navigation is… “process of planning,
documentation and control of a movement of a ship
or vehicle from one location to another”
[Bowditch 1802]
i. Positioning,
Navigation process
Navigation
Thomas Stüdeli
14 December 2009
ii. Determination of next target
position, landmarks and
possible hazards between
position and target position
i. Positioning,
determination of
actual position
iii. Movement,
and control of actions
Wayfinding

Navigation process …
• Classical navigation is an iterative process
that is intuitively understood.
• The process demands:
– spatial capacities (thinking in space)
– strategic decision making
– safety and risks analyzes
– management of parallel tasks
Thomas Stüdeli
14 December 2009
– management of parallel tasks
• Navigation is strongly influenced by
– vehicle and or involved tools
– navigation environment
– navigation task
• Medical procedures and surgical or
interventional tasks can be interpreted as
navigation processes.

Safe navigation ?
Factors: time, environment, tasks (demanded accuracy, prudence etc.)
Thomas Stüdeli
14 December 2009
Thomas Stüdeli
Basle 22 June 2009

Navigation vs. Wayfinding
• Navigation process demands:
– Spatial orientation
– Strategic decisions
– Safety and Risk
– Management of parallel tasks
• Supported e.g. by
topographical maps
• “all the perceptual, cognitive,
and decision-making
processes necessary to find
one’s way.”
[Arthur and Passini 1992]
• Supported e.g. by schematic
maps or car navigation
systems
Thomas Stüdeli
14 December 2009
topographical maps

Orientation
• Absence of orientation is called disorientation,
it’s seen as a symptom of confusion [Bellenkes et al 1992].
• Orientation is an active process: ”person's self-
awareness with regard to position, time and
place.”
Thomas Stüdeli
14 December 2009
place.”
• For every navigation step orientation is
synonymous for “Where am I?” (Shewhart cycle
(PDCA) Plan)
• Orientation is a “mental registration” –
registration of the mental spatial model to the
real environment (reality)

Wayfinding
[Allen 1999, Professional Geographer]
• Tasks
– Commute: travel along familiar routes in familiar
environments.
– Explore: travel into unfamiliar environments.
– Quest: exploratory travel in an unfamiliar environment to
Thomas Stüdeli
14 December 2009
– Quest: exploratory travel in an unfamiliar environment to
an unfamiliar destination.
• Strategies
– Depend on possible and preferred spatial updating
methods
– Field of save travel [Gibson & Crooks 1932, Dominguez 1997]
– …

Human body as navigation
environment
• Surgeons commute, explore and quest [Allen 1999,
Professional Geographer] the human body during MIS. The
navigation process depends on tissue
characteristics and the body region.
• Human body as a navigation environment can
be characterized by:
– Size of the working area (scale)
Thomas Stüdeli
14 December 2009
– Size of the working area (scale)
– Tissue properties (e.g. rigidity)
– Risks in the working area
• Wayfinding strategies differ e.g. between
– Small working areas, e.g. brain surgery small part of
a complex organ
– Single organ (liver, heart, kidney)
– Multiple organ (complicated and big abdominal or
heart surgeries).

Take home message…
Surgical navigation supports
• Be aware of the surgeons’ navigational
process:
– Parallel tasks
– Iterative process (feedback important).
• A support should aim to truly unburden the
surgeon from a specific (entire) task
Thomas Stüdeli
14 December 2009
surgeon from a specific (entire) task
(e.g. car navigation system: wayfinding strategy).
• Provide feed forward information not a feed
now information. Take in account the “field of
safe travel” and support learning of
movement patterns
(e.g. “in 200m to the right” and not “you are here”).

Human body as an navigation
environment
• The human body is an atypical navigation
environment with the special characteristics of
being
– relatively small in size
– not easily accessible
– non-rigid, and changeable.
• The human body is too different from the classical
Thomas Stüdeli
14 December 2009
• The human body is too different from the classical
navigation environments in order that existing
design guidelines for navigation aids can be
directly translated.
• Surgeons use the known cognitive concepts to
navigate and therefore those cognitive models on
human orientation, navigation and wayfinding help
to describe and understand surgical navigation.

Surgical navigation strategies
• Safety constraints:
– “Area of safe travel” (field of view, visibility)
– Demanded accuracy (distance to vital
structures)
• Accessibility and characteristics of
working area:
– Small part of a complex organ (e.g. brain
surgery)
– Single organ (e.g. liver, heart, kidney)
Thomas Stüdeli
14 December 2009
– Single organ (e.g. liver, heart, kidney)
– Body region with multiple organs (e.g. major
abdominal or heart surgeries)
• Different tissue characteristics in different
regions and organs (rigidity, changeability)
• Complexity of surgical task
– Shape and form of “surgical plain”
– …

• In the room
– Different teams
• In a team
– Changing teams
– Changing positions
• In surgical work place
and working field
Adaption of the user to the technology…
or … (re-)orientation in OR
Thomas Stüdeli
14 December 2009
• In surgical work place
and working field
– Direct and indirect
views
– Surgical tools
& complex technology,
e.g. robotic tools or
navigation system
[examples: IORT corectal cancer, ARIS*ER UI-Workshop, Catharine Hospital Eindhoven]

Safe Navigation
Position
Where am I? Hazards?
Destination
What do I want to see?
Where do I want to go?
What paths are possible?
References and Obstacles
What will I see?
Check
or Study
Plan
Do
New course
I move, and I control my
movements!
Act
Thomas Stüdeli
14 December 2009
What will I see?
What elements do I want to avoid?
• Two connected cycles (bold: navigation, italic: wayfinding)
• Strategic and safety related problems (wayfinding aspects)
• Location and orientation aspects (navigational aspects)
adapted from [Stüdeli 2008 ARIS*ER] & [Stüdeli 2009 GfA]
Based on [Shewhart 1939, Q-Kontroll-Zyklus, Plan-Do-Check-Act]
[Bowditch1802, The American Practical Navigator]

Questions
• What is the role of the different information
modalities?
– visual, haptic, mental model
– intra-operatively
Thomas Stüdeli
14 December 2009
– intra-operatively
(What can be transferred from pre-operative
planning into intra-operative planning?)
• What is the relation between spatial and safety
aspects?

Methods
• Structured interviews
– Interview (therapy, general type of difficulties,
successful navigation strategies)
– Sketch of “working area” (paper & pencil).
• Intra-operative observations
– Observation (n=3) surgeries or interventions (notes,
sketches)
– Encouraged to speak aloud everything that he/she
Thomas Stüdeli
14 December 2009
– Encouraged to speak aloud everything that he/she
was thinking and doing
– Scene camera (record of workflow and verbalizing)
• Analysis of interview data and sketches
– spatial-orientational variables: node, path, district,
landmark, edge (Lynch 1960, p.145),
– safety-strategical variables: hazards, degree of
accuracy, special attention
– information sources: direct view, indirect view,
haptic, mental model

Lynch’s elements vs.
anatomical landmarks
Landmarks
[Lynch 1960]
Functions Examples of anatomical
landmarks and landmarks used
by surgeons in human bodies
Node Focal point of travel Vessel bifurcations
Path Channel for navigation Vessels, needle trajectory
Thomas Stüdeli
14 December 2009
Path Channel for navigation
movement
Vessels, needle trajectory
(indicated through a navigational
aid)
District Reference point Familiar region, e.g. tissue
structures on a CT
Landmark Reference point into which
one does not enter
Vital structures
Edge Indicates district limits Capsules, ligaments, vessels

Catheter vs needle Intervention
• Catheter is flexible
• Path follows anatomy /
vascular system (inside
aorta, around organs)
• “Anatomical intervention”
• Needle is rigid
• Path follows needle
trajectory (across organs)
• “Unanatomical
intervention”
Thomas Stüdeli
14 December 2009
[pictures: Graduation report Thijs Van Oorschot 2009]

Spatial information need for surgical
action
Anatomical
(Catheter)
(n=2)
Mental
model
Visual
(d) direct
view
Haptic
Node *** *** **
Path *** ** ***
District *** ** **
Landmark ***
** **
• High importance of
mental model during
‘action’ (flow of work)
• Subjects acquire ‘as
much as possible’
Thomas Stüdeli
14 December 2009
** **
Edge **
Unanatomical
(Needle)
(n=2)
Node *** ** *
Path *** ** -
District *** * (d **) **
Landmark *** ** (d **)
**
Edge ** * (d **)
much as possible’
spatial information in
all modalities
• No differences in
use of edges and
landmarks on
medical images
*** Highly relevant (> 80%, 5 out of 6, found in interview, sketch, and verbalization)
** Relevant (> 50%, 3-4 out of 6)
* Minor importance (> 15%, minimal 1 out of 6)

spatial-orientational
vs
safety-strategical
Navigation Wayfinding
Position
Destination
References and
Obstacles
Check
or
Study
Plan
Do
New course
Act
Thomas Stüdeli
14 December 2009
Navigation
– Constant updating
– ‘As much as possible’
– ‘Optimization’ of
benefits (speed,
quality)
Wayfinding
– ‘Stop-and-go’
– Decision points
– Highly iterative
– ‘Minimization of
risks’

Two worlds…?
Position
Where am I?
Destination
What do I want to see?
What will I see?
Check
or Study
Plan
Do
New course
I move, and I control my
movements!
Act
Position
strategic and safety related
problems
(wayfinding aspects)
Thomas Stüdeli
14 December 2009
[adapted from Stüdeli 2009]
Position
Am I safe? Hazards?
Destination
Where do I want to go?
What elements do I want to avoid?
Check
or Study
Plan
Do
New course
I control my
movements!
Act
Control of location and
orientation
(navigational aspects)

Conclusions
• Mental model is highly relevant - even in
simple applications
– Transferred from pre-operative planning into
intra-operative planning is important
• Huge information need during MIS,
Thomas Stüdeli
14 December 2009
• Huge information need during MIS,
surgeons want “As much as possible”!
• Safety information is highly spatial, but not
necessary anatomical information
– E.g. Angles, volumes, areas, length, distance to
target

Agenda
• Navigation and wayfinding processes
(safe and prudent)
Thomas Stüdeli
14 December 2009
(safe and prudent)
• Recent research
• Outlook

Outlook & Questions
Research Methods?
• How to (better) quantify verbalization data?
• What does eye tracking offer?
Practical relevance for more complex
applications?
Thomas Stüdeli
14 December 2009
applications?
• Two surgeons, 4 eyes, two mental models?
• Collaborative mental models…?
Practical implication for Ergonomist and
Designers?
• Selection, priorization, and presentation of
information

Operation time
Surgical team
Technology
Safety / Information / Workload
Idea finding: Moderated
Workshops with Engineers
and MD
Design
Surgery
Systems
Architecture
& Graphics
Robotics &
Control
Thomas Stüdeli
14 December 2009
[Stüdeli, Freudenthal, de Ridder 2007 WWCS]
Thomas Stüdeli
iNNOVATION fORUM, Tuttlingen 23 June 2009
Ergonomics
Surgery
& Graphics
Computer
graphics
Robotics &
Control
Information
processing
and fusion

MRI-Technology
Surgery
Anaesthesiology
Ergonomics
Robotics &
Control
Final Animal tests for the ARIS*ER cardiac system
Thomas Stüdeli
14 December 2009
Systems
Architecture
& Graphics

Thank you for
your attention,
good bye and see
you again!
ARIS*ER is funded by the European Union as part of the 6th framework programme for research under the
Marie Curie Actions for Human Resources and Mobility, contract MRTN-CT-2004-512400.
Thomas Stüdeli
14 December 2009
Thomas Stüdeli
stuedelithomas@gmx.net
LinkedIn http://nl.linkedin.com/in/stuedelithomas
XING http://www.xing.com/profile/Thomas_Stuedeli

Surgical Navigation - insights into wayfinding and navigation processes in the human body

Recomendados

Recomendados

Mais conteúdo relacionado

Semelhante a Surgical Navigation - insights into wayfinding and navigation processes in the human body

Semelhante a Surgical Navigation - insights into wayfinding and navigation processes in the human body (20)

Último

Último (20)

Surgical Navigation - insights into wayfinding and navigation processes in the human body