3. A hemianopia is complete when the defect
follows the vertical meridian, has macular
splitting and involves the entire hemifield of
the affected side
All other visual field defects are termed as
incomplete and can be congruous or
incongrous
(Biousse 2010,Up To Date)
6. Confrontation testing
Perimertry (Humphrey and Goldmans)
Line bisection error analysis
Observation in function
7. There are various techniques, they are usually
kinetic or static and are widely used at
bedside
Confrontation testing was found to have
inadequate sensitivity as a screen (74%).
Although kinetic testing was superior to static
tests
Improved sensitivity was found when
confrontation tests were combined (78%)
Specificity was found to be 93%
8. Previous studies have found that patients
with Homonymous Hemianopia make
contralesional line bisection errors towards
their affected hemifield
Schuett et al (2010) found that this error was
made independent of the type of visual field
defect
It is believed to be related to an underlying
visual spatial disorder
Still unclear if this test could be used as a
reliable screening tool for visual field defect
9. Wall trailing
Head turning/tilting
Hesitancy
Stopping suddenly
Giving a wide berth
Going a long way round
Laboured scanning strategy
◦ Increase in saccades to blind field
◦ Inconsistant exploration of space
(Zihl 2000, Pambakakian 2000)
10. Reading
Collisions
Shopping
Anxiety/loss of confidence
Driving
Knocking things over
Financial management
Meal preparation
Disorientation
(Warren 2010,Pambakian 2000,Papageorgiou 2007)
11. Substitution/Optical therapy, not currently
recommended for routine practice by the RCP
guidelines (2008)
Compensation, RCP(2008) guidelines recommend
that techniques should be taught to overcome VF
loss
Restitution, not currently recommended
Recommendations based on 2 systematic reviews,
Riggs(2007) and Bouwmeester (2006)
12.
13. This novel prism placement was first trialled by Peli et al
(2000), who found positive results but it was only a small trial
Previously prism placement had caused distortion and
diplopia
Bowers et al(2008) trial was a larger and multi centred n=43
but was not randomised and there was no control group
(although an RCT is underway but has not yet been
published)
Bowers found positive acceptance by patients who found
them useful in mobility and obstacle avoidance (74% wearing
at 6 weeks,47% at 12 months)
14. What is Compensation in the literature?
◦ Saccadic visual search training(Pambakian
2004),explorative saccade training(Roth 2009) and visual
search training (Schofield 2009)
◦ All based on mass practice using computer based
technology for about 30 mins daily over a six week
period
◦ Improvement is mainly measured in terms of response
time of patients scanning into the hemianoptic field
◦ There is strengthening evidence that this training does
improve scanning into the hemianoptic field but what is
less clear is its impact on ADL’s
15. Did Angela receive typical current OT’s
practice?
How else do we encourage compensation?
Do we target response time or accuracy? Is
there a trade off?
16.
17. How do you read text?
outside foveal vision to
identify
24. Outcome = time on visual search in naturalistic
scenes.
Paperclip
25. 76 year old lady lives with husband,
previously independent
Had surgery on 29/06/10 to correct
complicated cataract surgery,this resulted in
loss af vision in left eye
Suffered a CVA post surgery
MR brain showed left Occipital and Cerebellar
infarcts
Right VF defect suspected through screening
26. Look out for increasing evidence into the use
of prisms
Be ready to do mass scanning practice using
technology either at home or in hospital
Combine screening methods to assess for
Visual field defects
Visual field defects can confound other visual
perceptual problems as well as cause them
27. Kerr et al (2010) Diagnostic accuracy of
confrontation visual field
tests,Neurology,13;74(15):1184-90
Pambakian et al (2000)Scanning the visual world:a
study of patients with homonymous hemianopia.
Journal of neurology Neurosurgery and psychiatry
69:751-9
Schuett et al (2010),Line bisection in unilateral
homonymous visual field defects,
Cortex,doi:10.1016/j.cortex.2010.01.008