Transcript Effect of cranial nerve lesions

EyeSim
An Ophthalmic Response Simulator
Meseret N. Teferra,
Prof K. Reynolds & Dr A. Mohtar
Project Objective
“To develop a simulator that can be used to
teach medical students how to examine the eyes
for cranial nerve lesions”
• Oculomotor nerve (cranial nerve III ) lesion
• Trochlear nerve (cranial nerve IV) lesion
• Abducense nerve (cranial nerve VI) lesion
Background
• During
ocular
dysfunction,
ophthalmologists
examine the eye so as to investigate the root cause of
the pathology: cranial nerve lesion being one of
them.
Effect of cranial nerve lesions
• Oculomotor nerve lesion (CN III):
• Loss of adduction, elevation and
depression.
• Loss of dilation of the pupil and
ptosis (droop) of the eyelid.
• Trochlear nerve lesion (CN IV) :
• Loss of depression and abduction.
• Abducense nerve lesion (CN VI):
• Loss of abduction.
Continued . . .
Ophthalmic examination: current practices
• Intra ocular muscle test
• Pupillary response
• Accommodation / visual field
• Extra ocular muscle test
• Examines the ability of the patient’s eye to track the
object at a distance of 10 to 14 inches.
Simulators in Medical Education
• K-E A ABOU-Elhamd et al. ddefined medical
simulation as an“educational environment in
which learning occurs through the use of a
device, mannequin or team without the
presence of an actual patient”(2010).
Why Simulators?
• Risk-free
environment
to
learn
critical
skills
(Friedrich, 2002).
• Allows for control of complexity and repeatability
(Østergaard, 2004).
• Provide balance between clinical and educational
outcomes (Laerdal, 2004).
Ophthalmic simulators
• Current teaching practices in ophthalmology are
mainly reliant on theory.
• The practical nature of the topics are very much
dependent either on the availability of patients in that
scenario or virtual reality simulators.
• Flinders university developed EyeSim in 2004 (Tim
Nelson, Engineering honours project).
• No other physical simulator have been identified.
EyeSim: What has been done before??
How EyeSim was integrated
What is new??
Continued . . .
How the new EyeSim is integrated
Continued . . .
• Control program / new method for object
tracking and IRIS brightness control
• SPIN based
• C based
Continued . . .
• New control board
• Arduino controlled
• CMUCAM4 for colour tracking
• New board to power up electrical components and for
proper signalling
• New servos (HS 55 , DS-928BB )
• 4 layer IRIS board
Features of the new EyeSim
• Stand alone
• Easy to operate and understand
• Two toggle switches installed on a panel
• Descriptive Back up LEDs
• Independent eye movement
• Two eyes which can follow an object and respond to
light
• Simulation can be
• Random
• Planned / Pre - known
What needs to be done
• Design
• Refine the control program
• The IRIS PCBs are found faulty and the design of a new
4 layer IRIS PCB is in progress
• The supporting frame will be adjusted accordingly
Continued . . .
• Manufacture and purchase
• The power and signalling board is ready for manufacture
• IRIS PCB
• The enclosure is already chosen and will soon be
purchased
• Assembly and prototype testing
Q??
Thank you for your attention!!