Lecture 19 + 20 - Guide dogs and environmental design Flashcards
Guide dogs for blind association:
• Started in 1933
• = 4,600 guide dog partnerships
• Guide dogs
• Training for dogs and VIP’s
• Buddy dogs
• Research
- Ophthalmic
- Dog health
• Running cost £45m pa
- 900 staff, 10,000 volunteers
• No government funding
The life of a guide dog:
• Labrador/Golden retriever & crosses, german shepherd
- 1000 puppies pa
• Training
- 20months
• Pairing
- 4 weeks
• Working life
- 7yrs
• Cost
- Food and vet bills
Role of Owner, and Dog
Guide Dog Owner
• Encourages dog
• Commands, directs & informs dog
• Day to day care
Dog
• Guide owner in straight line
• Avoid obstacles
• Stop at kerbs & steps
- Lead owner across road
• Find doors, road crossings etc
Guide dog assessment
3 Stages:
1. General information visit
- Owner receives information on general services and mobility training
2. Mobility assessment
- Medical status and cause & degree of vision impairment are assessed, possibility of non-guide dog training of canes considered
- Contra-indications of dogs are; sufficient sight, dislike of dogs, <16 years
3. Guide dog assessment
- Assessment of guide dog mobility instructor and if applicant is suitable they are trained to work and walk with dog, recognise + follow its movements and develop dog control + graphical awareness,
Breeding of guide dogs:
• Labrador/golden retriever cross 47%
• Labrador 35%
• Golden retriever 13%
• German shepherds 5%
• Other <1%
Simple things for environmental design:
• Move TV away from windows to avoid glare
• sit close to TV/ near blackboard
• Location of lights for reading (contrast, glare)
• Extra task lighting where required (kitchen, bathroom)
• May need to have room lights on during the day
• Sit on one side of teacher/TV etc. for hemianopic patient
Architectural designs:
• Suitable colour schemes
- Matt light coloured paint on walls
- Dark paint round doors, contrast surrounds to switches, plugs
Lighter door with contrasting handle
Dark flooring
- Hard flooring- sound
- Contrasting skirting boards
• Features to aid VIPs
- Wide doors (guide dog access)
- Sliding doors
- Auditory indicators (e.g. lifts)
- Handrails
- Enclosed staircases
- Tactile elements (e.g. floors)
No projections (radiators, fire extinguishers)
- Strip lighting
- Tactile and auditory signs, maps and floor plans in public buildings
• Features that hinder VIP’s
- glass doors, open staircases, poor signage
Rehabilitation quote:
“Rehabilitation is all about learning new ways of doing familiar tasks”
Psychological barriers to process of rehabilitation
• Concealment
- Early stages, px pretends to have full visual function as eyes look normal
- do not wish to admit disability as may feel others associate with cognitive decline
- Younger Px fear losing job and independence
• Patients refusing LVA’s
- May think all that needed is new glasses
- Associate visual impairment with “blindness”, therefore give up or have unrealistic expectations
- LVA’s too much effort; therefore need to investigate if px will use
Prognostic factors in predicting successful use of LVA’s
Measurement of success of LVA is important to establish if healthcare is effective and the benefits they receive. But what constitutes a successful LVA assessment and what does the Px perceive as success?
• Increase in VA?
• Increase in patient confidence?
• Improved performance doing required tasks?
• Improved reading speed/accuracy
• Frequency of use of LVA
Perceived success varies and depends on individuals goals and expectations - if cant be met need to be honest with Px
What scientific study on VA performance is linked with LVA?
• Humphrey & Thompson
• Main-outcomes:
- Success rates vary considerably depending on criteria
- Up to 956 Px achieve acuity improvement
Improvement vision is not always sign of success, as may be difficult or inconvenient to get good VA
What scientific study on VA Quality of life is linked with LVA?
• Manchester low vision questionnaire
- 84px
- Findings suggested most Px use LVA’s and rate them very important
What scientific study on benefit from attending LVA clinic?
• Leat and fryer 1994
- Benefits from attending the clinic were reported by 89.5% of patients and 81% of patients were regularly using low vision aids.
“Do you benefit from the use of LVAs?”
• 68.7% ‘a great deal’
• 22.8% ‘a little’
• 10.5% ‘not at all’
Predictors for successful LVA use;
• Visual acuity
• Visual field
• Stability if eye condition
• Duration of visual impairment
• Cause of visual impairment/eye condition
• Age
• Education & intelligence
• Motivation
Describe Predictors: Visual acuity, Visual field, Stability if eye condition
• Visual acuity - Poor - Improved VA does not mean LVA is easy to use or will be used
• Visual field - good - The extent and location of remaining vision is important: restricted field tend to have poor prognosis
• Stability if eye condition- good - better chance of success if stable
Describe Predictors: Duration of visual impairment, Cause of visual impairment/eye condition, Age
• Duration of visual impairment: Good - Poor prognosis if recent (loss model)
• Cause of visual impairment/eye condition - poor
• Age - good - younger have better prognosis - motivation?
Describe predictors: Education & intelligence, Motivation
• Education & intelligence: poor - better educated/intelligent tend to have success, fluid intelligence (adaptation to new ways and problem solving) more important than crystallised intelligence (built up over years)
• Motivation: good - probably the most important factor!
Which do patients like best?
• Spectacle prescriptions (high adds)
• Hand magnifiers
• Stand magnifiers
• Illuminated magnifiers
Incidence vs prevalence:
• Prevalence- number of cases that exist at a certain time or in an area (expressed as a % of total population)
• Incidence- Number of new cases in a certain period and area (frequency of occurrence)
Prevalence of vision impairment
• 1bn worldwide
• 300k UK
• Greater among women
• Greater in south asia
• Older age = higher prevalence
Most common causes of visual blindness SCOTLAND
• ARMD : 57%
• Glaucoma : 16.3%
• Myopia + optic atrophy is 7%
Causes of visual impairment (UK + World wide)
• Refractive error (150m)
• Cataract (90m)
• Macular degen (20m)
• Glaucoma (20m)
• DM (20m)
• Other (10m)
Preventable/treatable blindness:
Preventable
• Refractive error
• Cataract
• Trachoma
• Onchocerciasis
• Micronutrient deficiencies
- Vit A
Treatable
• Childhood Blindness / Low Vision
• Glaucoma
• Diabetic Retinopathy
• Age Related macular degeneration
Treatment for cataract:
• Affects ~ 16m worldwide
• IOL cost ~ US $10 -very cost effective
- Study found 85% men 58% women return to work
- Financial return of 1500% on cost of surgery
Treatment for Onchoceriasis:
Onchocerciasis
• Onchocerciasis control programme- West Africa, 11 countries
• Protected 30m people incl. 10m children
• Cost US$1 per person
Treatment for Vitamin A deficiency
• Xerophthalmia
350,000 children blind pa
- Increases child mortality by 20%
• Prevented by good diet fruit veg etc
Treatment for diabetes:
• 2% of UK population are known diabetics
• 10% will have diabetic retinopathy requiring ophthalmological intervention
• Untreated 6-9% of those with proliferate DR would become blind each year
• Affects working age group
• High costs
- screening & treatment cost effective
General techniques for prevention of blindness worldwide:
• Immunisation
• Nutrition & education
• Personal hygiene
• Sanitation
• Training & local medical facilities
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