Visual Impairment Scotland Report
Chapter 11 Blind and Partial Sight Registration other services
Overall registration rates
- Time course from birth to registration
- Visual function
- Anatomical site
- Additional disabilities
- Age groups
- Recommended criteria and registration rates
Of the 333 children with significant visual impairment 198 (59%) were registered either blind or partially sighted.
Once a child was confirmed to be visually impaired it took on average 3 years for blind or partial sight registration to take place.
There were children registered blind or partially sighted in all visual function groups. There was a clear trend for a greater percentage of children to be registered blind in the visual function groups with poorer vision.
Children with a visual impairment due to conditions of the brain were less likely to be registered blind or partially sighted (47%) than children where the eye or optic nerve (70%) was the primary anatomical site of impairment.
Children with additional disabilities were less likely to be registered blind or partially sighted (55%) than children without additional disabilities (65%). This is despite children with additional disabilities having worse overall visual function.
11.1 Overall Registration Rates
Of the 333 children with ?significant visual impairment? 198 (59%) were registered either blind or partially sighted. Conversely a large percentage of children (41%) were not registered.
Of the 198 children registered just under half (94) were registered partially sighted and just over half (104) were registered blind.
Complete information on four critical times in the diagnostic and registration process was available to VIS on 60 children registered blind and 49 registered partially sighted. All children on the VIS database were included in this analysis and not just those who were under 16 years of age. The four dates include:
- When parents first suspected their child to be visually impaired
- Diagnosis of medical condition causing visual impairment
- Confirmation of visual impairment by health professionals
- Blind or partial sight registration
A summary of the average number of months from birth to the each of these four time points is described in figure 11.2.
In children who were eventually registered blind it took on average just over 7 months from the time of birth for parents to suspect their child was visually impaired. It took on average a further 4 months to confirm that the child was visually impaired and then another 3 months to confirm the cause of the impairment. It then took on average 33 months for the child to be added to the blind register. The time course for partial sight registration was similar but with the initial 3 time points all being between 1 and 2 years later. The eventual average time gap between confirmation of visual impairment and partial sight registration was similar to blind registration at 36 months. There was a large range of time gaps between when parents first suspected their child was visually impaired and when the child eventually became registered blind (Figure 11.3) or partially sighted (Figure 11.4).
Half of the children (30/60) were registered blind within 2 years of becoming symptomatic. However for over 25% (16/60) of the children blind registration took over 4 years to be performed and for a small group of children (4) it took over 14 years.
For partial sight registration there was a similarly large range of time gaps between initial symptoms of visual impairment and being registered partially sighted. Half of the children (25/49) were registered by 4 years. There was however a small group of children (4) for whom it took over 10 years from initial symptoms of visual impairment to partial sight registration.
The function of the official register is to receive notification of new presentations of children with visual impairment with the aim of initiating and coordinating an early and effective cross-discipline habilitation team. It is clear that many children become registered several years after the onset of their visual impairment. The effect of this delay is unknown although from the evidence currently available delay in receiving appropriate co-ordinated services could lead to a sub-optimal developmental outcome.
There were children registered blind in all NORDSYN visual function groups.
*Children with visual field loss are reclassified into the next higher group but are not moved from Group C to D. A further VIS modification to this system is to move children with cognitive visual dysfunction with visual acuity better >6/18 into Group A.
There was a clear trend for a greater percentage of children to be registered blind in the visual function groups with poorer vision. This ranged from 6% in the ?low vision? Group A (6/18 to 6/60) to 88% in the ?blind? Group D (no perception of light). There are instances in which children with less severe visual impairment or apparently less severe visual impairment might be registered ?blind?. Examples include:
- Blind registration of a child early in life where visual function was very poor but as the child grows older, as is often the case, visual function improves but registration status may not be amended. The earlier registration occurs the more likely is this occurrence.
- Blind registration of a child with symptoms of cognitive visual dysfunction (eg: inability to see movement or more than one thing at the same time) in whom visual acuity and visual field assessment are essentially normal.
Children with visual impairment due to the brain were less likely to be registered blind or partially sighted (47%) than children where the eye or optic nerve (70%) is the primary anatomical site of impairment. This is despite children with brain as the primary impairing site suffering worse overall visual function.
Children with additional disabilities were less likely to be registered blind or partially sighted (55%) than children without additional disabilities (65%). Despite such children being likely to have worse visual function.
There were no children under the age of 2 years registered blind or partially sighted. Overall two fifths of pre-school children were registered. This contrasts with primary and secondary school children of whom approximately two thirds were registered.
Blind registrations show a declining trend in the older age groups.
This contrasts with partial sight registration which clearly increase in the older age groups.
The recommended criteria for registration as blind or partially sighted in Scotland, as described on the BP1 certification form23 includes a visual acuity of worse than 6/60 or ?marked contraction of the fields? regardless of visual acuity. 181 children were identified who fulfilled the criteria and 152 who did not fulfil the recommended visual acuity and visual field loss criteria.
Three quarters (75%) of the children who fulfilled the criteria were registered and half (50%) of the children who did not meet the recommended criteria were registered.
To register a child as blind or partially sighted an ophthalmologist must determine whether the child is likely to grow up to meet the generic definitions as described on the BP1 certification form. The definition of blind is ?to be so blind as to be unable to perform any work for which eyesight is essential?. The definition of partially sighted is ?to be substantially and permanently handicapped by congenitally defective vision?. In reality it is not possible to make either of these judgments for a young child, and the above statistics indicate that ophthalmologists have had to apply their discretion concerning the definitions of visual impairment and blindness but it has not been practicable to meet the recommendations, which were designed to meet the needs of adults.