Blind and Partially-sighted Children (1968)

This Survey of more than 2,000 children in 54 special schools and eight special classes in England and Wales was written for the DES by Dr Shirley R Fine.

The complete document is presented in this single web page. You can scroll through it or use the following links to go straight to the various sections:

Introduction (page 1)
Blind children (3)
Partially sighted children (45)

Note Many of the tables in this document were printed across two pages. For convenience, they are presented here as single images.

The text of Blind and Partially-sighted Children was prepared by Derek Gillard and uploaded on 6 December 2022.

Department of Education and Science
London: 1968
© Crown copyright material is reproduced with the permission of the Controller of HMSO and the Queen's Printer for Scotland.

[cover]

[title page]

Blind and
Partially-sighted
Children

Education Survey 4

by Dr. Shirley R. Fine

Department of Education and Science

London: Her Majesty's Stationery Office 1968

[page ii]

Acknowledgments

Dr. Anne Guy, while working as a medical officer in the Ministry of Education in 1962-63, initiated this survey, and I have included in my analysis 288 blind and 259 partially sighted children seen by her.

I am grateful to the headmasters and headmistresses and staffs of the schools visited for their help in this enquiry and to the school medical officers and ophthalmologists for making their records available to me. I am specially grateful to Dr. P. Henderson and Professor A. Sorsby for their advice and encouragement in the preparation of the report of this survey.

S. R. F.

[page iii]

Contents

[page 1]

Introduction

This survey of 817 children in 20 special schools for the blind and of 1,374 children in 34 special schools and eight special classes for partially sighted pupils in England and Wales was carried out between 1962 and 1965. Each school was visited at least once and all children born on or after January 1, 1951, who were on the roll at the time of the visit were included.

Information was obtained by perusal of the medical records, including Blind Registration Forms BD8, often completed in early infancy, the findings of recent ophthalmological examinations, school medical cards giving details of general health and other handicaps, and reports of psychological testing where available. Each child was then discussed with the teacher and observed in the classroom at work and sometimes at play. A few children were given the Williams adaptation of the Stanford-Binet test by the investigator where the intelligence quotient was not readily obtainable from other sources.

A general feature of special educational provision is that there are more boys than girls in the special schools for all the various types of handicap. In schools for the blind, however, there were as many girls as boys with retrolental fibroplasia, giving an exceptionally high proportion of girls born in the years from 1949 to 1953.

For the purpose of the survey the children were placed in two groups: Group A, comprising those born in 1951 to 1955, years of temporarily high prevalence of retrolental fibroplasia, and Group B, those born in 1956 to 1960.

[page 3]

Blind Children

Clinical diagnosis

The various clinical conditions causing blindness in the pupils surveyed are given in Table 1. Since the abnormal number of children blinded by retrolental fibroplasia distorts the relative percentages of the various other conditions causing blindness, Table 1 also gives the relative percentages of these conditions with the children blinded by retrolental fibroplasia excluded.

Retrolental fibroplasia was the cause of blindness of 38.4 per cent of the children in Group A and of 10.8 per cent of those in Group B. Excluding these children, optic atrophy was the major cause of blindness in both groups, closely followed by cataract, each contributing over 20 per cent to the totals. Diseases of the retina and choroid were a heterogeneous collection of conditions, some of which, e.g. retinal detachment and the so called abiotrophic disorders, may develop during childhood rather than become evident at or soon after birth; they accounted for 14 per cent in Group A and 9.1 per cent in Group B. Coloboma and other developmental defects of the eye were discoverable in early infancy and accounted for the blindness of about twice the proportion of children in Group B (15.2 per cent) as in Group A (8.1 per cent), suggesting an increased survival rate in recent years and possibly a greater incidence. There were rather more children proportionately with tumour of the eye in Group B (10.8 per cent) than in Group A (7.6 per cent). Buphthalmos constituted the seventh major cause and was equally prevalent in both groups. Uveitis was another disease occurring during childhood and so affected a higher percentage of children in Group A. The other conditions were comparatively rare in schools for the blind and no general conclusions could be drawn. 'Cerebral blindness' included diagnoses of 'cortical blindness' and 'amaurosis'.

Aetiology

From the information available an attempt was made to determine the aetiology of the condition found in each child. Sometimes this was stated by the certifying surgeon on Form BD8, but in other cases a family history of similar eye disease, low birth-weight or later recollection of maternal infection during the pregnancy pointed to the most likely precipitating factor. Post-natal infection, intracranial lesions and trauma were responsible for a small number of affected children in both age groups. Table 2 shows that if the 242 children

with retrolental fibroplasia were excluded, about half the remainder (282 out of 575) were blind from a clinical condition of unknown aetiology, whether congenital or developing during childhood. In a survey of this nature it was not possible to correlate actual birth-weights of all premature infants with subsequent findings, nor to give details of possible modes of inheritance.

All children with retrolental fibroplasia were premature. It is interesting to note that in pseudoglioma, a condition with which it was confused clinically until its pathology was understood, only one child, with a birth-weight of 5 lb. 4 oz. [2.38kg], was by definition premature, although it was unlikely that prematurity was the underlying reason for the affection in this case. Other pseudogliomatous lesions were doubtfully associated with intra-uterine infection and with a family history of eye defects such as coloboma, glaucoma and cataracts.

Optic atrophy was brought about by a large variety of recognised factors,

[page 5]

although even here the largest group was of unknown aetiology. A definite family history was obtained in only 11 and prematurity was associated with 15 of the 142 cases. Infection was by tuberculosis and other forms of meningitis. Intracranial causes included tumours, such as craniopharyngioma and astrocytoma, as well as hydrocephalus. Trauma was by birth injury, cerebrovascular accident or fractured skull. The child whose blindness was ascribed to maternal infection, by toxoplasmosis, also had lesions of the retina and choroid, but the major diagnosis was optic atrophy.

Cataract was the group in which a family history was most in evidence, more girls being affected by the hereditary type than boys in both age groups. Cataract was associated with maternal rubella in pregnancy in 18 children. Of the 11 who were premature, one had an unaffected twin.

Diseases of the retina and choroid showed a marked sex difference in the

[pages 6-7]

[page 8]

hereditary group with 16 boys but only three girls. Prematurity was an associated finding in one girl. Maternal infection, by toxoplasmosis, was responsible for choroidal disease in two boys and one girl in each age group. Post-natal infection, by severe gastro-enteritis, was said to have caused one older boy's lesion, and trauma, including retinal detachment in myopia, accounted for the visual defect of six older and three younger boys. The aetiology was unknown in 33 of the 69 children with these diseases.

Of developmental anomalies including coloboma, anophthalmos, microphthalmos and aniridia, 15 were associated with a family history, four with prematurity, four were ascribed to maternal infection by rubella, toxoplasmosis or influenza during pregnancy, and 39 of the 63 were of unknown aetiology.

Tumours of the eye in this series were all of unknown aetiology, with no family history of similar defect.

Of the children with buphthalmos and juvenile glaucoma, the condition was considered to be hereditary in one older boy and three younger girls. One girl had post-natal infection by severe ophthalmia neonatorum, resulting in unilateral enucleation and glaucoma in the remaining eye, and 36 of the 41 were of unknown aetiology in this disease.

Uveitis chiefly resulted from Still's disease (juvenile rheumatism), affecting 13 children, but one case of iridocyclitis was associated with a family history of glaucoma and two were of unknown aetiology.

Nystagmus, unaccompanied by other identifiable ocular abnormality, was familial in six, and of unknown aetiology in eight children.

Corneal lesions consisted of hereditary corneal dystrophy in one girl; keratitis said to be caused by maternal rubella in two girls and by congenital syphilis

Table 3 Distribution of visual acuity in relation to dominant handicap in the 817 children examined in schools for the blind

[page 9]

in one boy; one each of the remaining cases was ascribed to post-natal infection and trauma, five being of unknown aetiology.

Myopia was of the progressive and degenerative type, three out of a total of nine boys having a family history of eye disease.

Penetrating injury with sympathetic ophthalmia caused blindness in four boys and two girls.

Cerebral blindness was associated with a family history in two children, with infection by encephalitis affecting the visual cortex in one girl and with trauma causing sinus thrombosis affecting vision in one boy, while six cases were of unknown aetiology.

Albinism was found in seven boys and one girl, of whom four boys and the girl had a family history of similar defect.

Visual acuity and visual fields

Table 3 shows the visual acuity in relation to the dominant handicap as assessed by the investigator: 717 of the 817 children were considered to be correctly placed in schools for the blind; 80 were thought to be partially sighted rather than blind; four had other severe handicaps in addition to blindness, and there was serious doubt as to the suitability of 16 for any form of education.

Some of the 80 children considered to be partially sighted rather than blind were able to make good educational use of such limited vision as 2/60 or less; the two who had perception of light only were thought by their teachers to have better vision than that estimated by the ophthalmologists in formal

[page 10]

testing. A few were in process of transfer to schools or classes for partially sighted pupils and one to ordinary school; others had failed elsewhere, but were thought by their teachers to be capable of learning by sighted methods.

Of the four children placed in other educational categories, two were primarily educationally subnormal, one maladjusted and one physically handicapped; all four had very severe visual defects and appropriate educational provision would probably best be obtained for them in the schools for blind children with additional handicaps.

Nine children were too young for their visual acuity to be assessed with any certainty, but six were thought to be suitably placed in schools for the blind, two were probably partially sighted and it was likely that one would be found unsuitable for education at school.

Of those considered to be partially sighted, eight of the 14 with visual acuity 6/36 - 6/24, 19 of the 42 with 3/60 - 6/60, and seven of the 19 with visual acuity of hand movements - 2/60 also had some restriction of their visual fields.

Of those considered to be well placed in schools for the blind, 27 of the 61 with visual acuity 3/60 - 6/60, the girl with 63/6 - 6/24 and the boy with 6/18 or better had restricted visual fields.

Schools previously attended

Of the 817 children, 614 had received all their education in schools for the blind, 63 had previously attended special schools or classes for the partially

Table 4 Mobility related to visual acuity, years of birth and presence of a physical handicap in blind children

[page 11]

sighted and 140 had been at ordinary schools. No fewer than 142 of the 203 children who had not had all their education in schools for the blind had visual acuity less than 2/60.

The personality and intelligence of a child, as well as his estimated visual acuity and field of vision, have to be taken into account when a decision is being made about his educational placement.

Mobility

Mobility was assessed by the teachers and the investigator, bearing in mind the amount of useful vision of each child and comparing him with others of his own age and experience. Mobility other than 'good' was classed as 'poor' in Table 4, and the 24 older and 12 younger children with a physical handicap affecting mobility were excluded from the percentage calculations. Of the other children, 23 per cent of older boys, 28 per cent of older girls, 25 per cent of younger boys and 32 per cent of younger girls had poor mobility, worse in girls and improving slightly with age. As expected, the percentage of children with poor mobility increased as visual acuity decreased, except where small numbers gave freak results: two older boys out of six with visual acuity of 6/36 - 6/24 and two younger girls out of 12 with visual acuity of 3/60 - 6/60 had unduly poor mobility, the explanation of which may have been related to other factors such as intelligence.

Mobility was also related to intelligence in the group of children born in 1951, 1953 and 1955. Figure 1 gives the findings. The spread of intelligence

[page 12]

Figure 1

RELATIONSHIP OF INTELLIGENCE QUOTIENT TO MOBILITY OF CHILDREN BORN IN 1951,1953 AND 1955 (Blind children)

[page 13]

extended in the usual pattern, but with the peak displaced to the right for those with good mobility. When poor mobility due to physical handicap was combined with other causes, the general shift to the left for poor mobility was even further accentuated. Good mobility was directly related to good intelligence, as well as to good visual acuity and to increase in age and experience, and was also rather better in boys than in girls.

Intelligence

An Intelligence Quotient was obtained for 315 (91 per cent) of the 345 children born in 1951, 1953 and 1955, to provide a representative sample of the 817 children in the survey. Table 5 shows the range of intelligence in relation to the causes of blindness.

The IQ distribution of subnormal or dull (50-84), average (85-114) and superior or gifted (115+) in the child population as a whole can be taken as approximately in the ratio of 15:70:15, whereas in this survey the ratio for blind children in school was 23:59:18.

When individual causes of blindness were considered, striking differences in the ratios emerged: of the children with retrolental fibroplasia, all of whom were known to be premature, only nine per cent were gifted, 70 per cent average and 21 per cent dull; of those with optic atrophy, some of whom had associated brain damage from a variety of lesions, again only nine per cent were gifted, 45 per cent were average and 46 per cent were dull. On the other hand, there was a high percentage of gifted children with cataract and diseases of the retina and choroid (29 per cent) and with tumour of the eye (43 per cent). No child with tumour of the eye in the sample group was in the dull range of intelligence, and in the whole survey only one boy with this cause of blindness was found to have the additional handicap of low intelligence (see Table 6); this finding confirmed the widely held opinion that these children are often intellectually gifted.

The children with the other conditions listed in Table 5 were too few for comment.

Additional handicaps

Altogether, 50 per cent of the older boys, 49 per cent of the older girls, 59 per cent of the younger boys and 54 per cent of the younger girls had additional handicaps; of those affected, older boys and all girls each had an average of 1.6, and younger boys 1.7, additional handicaps.

Table 6 shows additional handicaps related to causes of blindness. Where an IQ result was available, it provided a guide to the intelligence of the child: when the IQ was below 70 the child's low intelligence was regarded, for the

[page 14]

purposes of this survey, as an additional handicap. Any child considered by its teacher as being of limited intellect, although no formal testing had been carried out, was also included. Physical disability, hearing loss, maladjustment, speech and language difficulty were noted even if a child was only mildly affected. Other defects included persistent bedwetting, obesity, eczema, bronchitis, asthma and general debility.

For Group A, physical disability provided 25.4 per cent of the total handicaps and low intelligence 19.8 per cent, whereas for Group B low intelligence accounted for 31.5 per cent and physical disability 23.0 per cent. Of the 817 children in the survey, 20.3 per cent had low intelligence, 20.7 physical disability, 9.2 hearing loss, 9.2 (not necessarily the same children) speech and language difficulty, 8.9 had evidence of maladjustment and 7.6 epilepsy as additional handicaps. When the children with retrolental fibroplasia were excluded from the calculations, the relative percentages were very little altered.

[page 15]

Mannerisms

Mannerisms were common in children in schools for the blind and seemed to be instinctive rather than copied from others; 45 per cent of the children were affected and many had more than one mannerism. The commonest were eye-poking, rocking, hand-flapping, head-nodding and twirling, but others included fidgeting and jerking, finger-sucking and nailbiting, jumping up and down, head drooping, grimacing and scratching. Table 7 shows the prevalence of mannerisms in relation to the major causes of blindness in older and younger boys. and girls. For each cause, the percentage of affected children was calculated and included in the tabulation. The largest number of mannerisms in both age groups was associated with retrolental fibroplasia, 71 per cent of older and 93 per cent of younger children being affected; although those with pseudoglioma were few in number, 87 per cent of older and 83 per cent of younger children had mannerisms. Buphthalmos and corneal lesions in younger children, cerebral blindness in older children and nystagmus in both

[pages 16-17]

Table 7 Mannerisms in relation to causes of blindness

[pages 18-19]

[page 20]

age groups showed high percentages of mannerisms among the small numbers of children with these conditions. Those with albinism, said by some observers to be irritable and over-active, had no mannerisms, and percentages with mannerisms were particularly low for children with tumour of the eye.

Figure 2 shows the relationship of mannerisms to intelligence among the 315 children born in 1951, 1953 and 1955 whose IQs were recorded. Mannerisms occurred throughout the whole range of intelligence, but were more prevalent among those below average.

Main teaching medium and use of visual aids

Braille was the main medium for 685 of the 817 children, but for some with poor intellect or poor sensitivity or control of the hands making the reading of Braille difficult, alternative methods were employed. Some children with a limited amount of vision made use of visual aids, whether teaching was by sighted methods, by Braille or by both. Others with little or no sight were taught by oral methods, except for the few with grossly impaired hearing and vision, who were taught individually by specialised means. Table 8 gives details.

Table 8 Main teaching medium and use of visual aids

Attitudes of children, parents and teachers

Home circumstances varied and were considered abnormal if the parents were dead, divorced, in prison or were well-recognised problem families, or if the child was adopted, fostered or in the care of the local authority. Abnormal parental attitudes ranged from over-indulgence and over-protection to complete rejection. The child's attitude was considered in relation to school and staff, to his fellows and to his handicap. Resentment of the visual handicap was rare in younger pupils, but when it developed it was usually at adolescence. While many resented an additional physical handicap, they accepted the visual defect as normal in the society in which they lived and worked.

Of the 817 children, 348 boys and 262 girls had a satisfactory attitude to school, staff, other children and to their handicap, but 120 boys and 87 girls

[page 21]

Figure 2

RELATIONSHIP OF INTELLlGENCE QUOTIENT TO PRESENCE OF MANNERISMS IN CHILDREN BORN IN 1951, 1953 AND 1955 (Blind children)

were judged unsatisfactory in one or more respects. Homes were abnormal for 67 boys and 50 girls, of whom 25 boys and 21 girls had unsatisfactory attitudes; parental attitudes were abnormal for 180 boys and 132 girls, of whom 65 boys and 53 girls also had unsatisfactory attitudes.

The teachers considered that 99 of the 120 boys with unsatisfactory attitudes were emotionally disturbed to an appreciable extent and 63 were not working to capacity, whereas of 348 boys with satisfactory attitudes, 78 were emotionally disturbed and 70 not working to capacity. Of the 87 girls with unsatisfactory attitudes, 58 were emotionally disturbed and 38 not working to capacity, whereas of 262 girls with satisfactory attitudes, 58 were emotionally disturbed and 43 not working to capacity. Altogether, 36 per cent of the children were thought by their teachers to be emotionally disturbed; despite adverse home conditions and parental attitudes some of the children were remarkably resilient to their difficult circumstances but, on the whole, problems in the home tended to be associated with disappointing progress at school.

[page 22]

Summary

1. A survey was made of a defined group of 817 children in all schools for the blind in England and Wales.

2. The causes of blindness in these children were analysed in two groups: A, those born in 1951 to 1955, and B, those born in 1956 to 1960. In the first group retrolental fibroplasia predominated, with optic atrophy in second place; in the second group optic atrophy was commonest with cataract in second place.

3. Omitting prematurity associated with retrolental fibroplasia, most conditions were of unknown aetiology; a genetic basis was the commonest known factor.

4. Visual acuity ranged from no perception of light to 6/18 with restriction of visual fields. Most of the children were thought to be suitably placed in schools for the blind, but for 100 there was still some doubt; 203 pupils had been transferred from sighted schools or schools and classes for the partially sighted.

5. Poor mobility was related to poor visual acuity and to the presence of a physical handicap as well as, in a sample group, to poor intelligence. Mobility improved with increase in age, particularly in girls, in whom, in both age groups, it was less good than in boys.

6. Intelligence Quotients were estimated for children born in 1951, 1953 and 1955 and comparisons made in the major clinical groups: those with tumours of the eye, diseases of the retina and choroid, cataract and a few other conditions tended to have higher than average, and those with optic atrophy and retrolental fibroplasia lower than average intellectual abilities.

7. Additional handicaps were collated for Groups A and B, and the pattern of handicaps compared: physical handicap was the commonest additional handicap in the older group (even when children with retrolental fibroplasia were excluded) and low intelligence in the younger group.

8. The mannerisms of blind children were enumerated and assessed in relation to causes of blindness, to age and to intelligence: retrolental fibroplasia and pseudoglioma were found to have the most significant precipitating effect.

9. The main teaching medium was Braille, but other methods were employed where this was unsuitable. Visual aids were used by some children taught by Braille as well as by some using sighted methods.

[page 23]

10. The relationship between home and parents' and children's attitudes was examined, and the effect of these on the assessment, by the teachers, of emotional stability and educational progress was noted. Although unsatisfactory attitudes and abnormal home circumstances adversely affected many children, some were undaunted by their unfavourable conditions.

11. The large number of children who were emotionally disturbed (36 per cent) and/or had mannerisms (45 per cent) indicated a need for psychological and psychiatric investigation.

[page 24]

Partially Sighted Children

Clinical diagnosis

Sight-saving classes, mainly for children with myopia, were first started in 1908. Since then, however, as shown in Table 9, cataract has become the chief cause for admission to the special schools and classes; myopia came second in the older and fifth in the younger group, with optic atrophy, nystagmus and albinism in the intervening places. For the reasons given in the discussion relating to blind children, the number and percentage affected by diseases of the retina and choroid were considerably larger in Group A than in Group B. Retrolental fibroplasia, the peak incidence of which was in the

Table 9 Distribution of causes of partial sight in survey pupils

[page 25]

years 1949 to 1953, was responsible for the visual defect of six per cent of children in Group A and 4.1 per cent in Group B. Coloboma and developmental defects comprised six per cent and 5.8 per cent respectively of the two groups. The children with tumour of the eye had had one eye enucleated and the remaining eye irradiated; unilateral blindness with good vision in the other eye would not usually be a justifiable reason for special educational treatment as a partially sighted pupil. The various other conditions affected very few children.

Since many young children with considerable visual defect first attend ordinary infant schools and are later transferred to special schools and classes, often some distance from their homes, the comparisons made here of prevalence of various conditions according to age must be viewed with caution. It is likely, however, that the most severely affected are admitted early for special educational treatment, especially where there is a family history of a

[pages 26-27]

Table 10 Aetiology of partial sight in the major clinical groups

[page 28]

similar condition or an obvious defect such as cataract. There is also some interchange between schools for the blind and those for the partially sighted.

Boys comprised 60 per cent of children in Group A and 62 per cent in Group B. The six commonest conditions found in the survey of partially sighted pupils showed a marked predominance in boys, but retrolental fibroplasia, developmental defects and buphthalmos affected an almost equal number of boys and girls.

Aetiology

Table 10 shows that the cause of the clinical condition in 627 (45.6 per cent) of the 1,374 children was unknown; heredity was the commonest known factor (34.4 per cent). Of the 149 children born premature, 75 had retrolental fibroplasia. Maternal infection (rubella, syphilis, influenza or presumed toxoplasmosis) affected 56 and post-natal infection 27 children. Intracranial causes in 18 children included brain tumours, hydrocephalus and cerebrovascular lesions. Trauma involved 24 children and included head injuries, poisoning or sensitivity reactions, local corneal lesions and detachments of the retina.

In cataract there was a strong hereditary factor, particularly in girls - a finding that was even more evident in the survey of blind pupils. Maternal infection by rubella or suspected rubella had affected 36 children. Prematurity was noted in 29 otherwise unexplained cases. Of the 163 with unknown aetiology, three were associated with galactosaemia.

Dislocation of the lens was familial in 25 out of 42 children and was part of Marten's syndrome or homocystinuria or an isolated lesion in both the unknown and the hereditary groups.

A family history of myopia, not necessarily of such severity as to require special education as a partially sighted pupil, was present in 87 of the 172 children with this condition. Prematurity with early onset of visual defect was noted in 16 cases; infection by meningitis was followed by myopia in two cases, and hydrocephalus was said to have been responsible for myopia in one younger girl.

Many factors were involved in the causation of optic atrophy, as was also found in blind children: an hereditary influence was more marked in boys than in girls; prematurity was noted in 16 otherwise unexplained cases; maternal infection in one older boy was thought to be by toxoplasmosis also producing choroiditis; post-natal infection was by tuberculous meningitis in all but one case, which was ascribed to measles; intracranial lesions in 17 children included hydrocephalus, suprasellar tumour, craniopharyngioma,

[page 29]

astrocytoma, neurofibroma and cerebellar glioma; trauma in 11 children included birth injury, fractured skull, subdural haemorrhage, chloromycetin sensitivity reaction and poisoning by mercury.

Nystagmus was taken as the cause only where no other ocular lesion was present, since it accompanied many of the other eye conditions. There was a strong familial element more marked in boys (52) than in girls (11). Prematurity was noted in six cases, trauma by birth injury in three and fractured skull in one.

Of the 141 children with albinism, 69 had a family history of the condition, but the aetiology was unknown in the others. More boys were affected than girls and all degrees of albinism were seen from complete absence of pigment (including some children of dark-skinned parentage) to apparently normally pigmented children whose fundi on retinoscopy had been found albinotic.

There was an hereditary factor in 34 of the 98 children with diseases of the retina and choroid; one particular family with its ramifications was responsible for at least eight boys and girls with macular degeneration. Prematurity was noted in four children, of whom one had retinal detachment and three had various kinds of retinal disorder. Maternal infection was by toxoplasmosis in all but two cases, one of which was ascribed to rubella and the other to syphilis. Post-natal infection was the presumed aetiology when macular lesions developed after a squint operation in one boy. Trauma caused retinal detachments in three children, and one boy with mottling of the macula said to have been caused by a solar burn has more recently been diagnosed as an example of Stargardt's disease.

Prematurity and the maladministration of oxygen were responsible for retrolental fibroplasia in 75 children, of whom 17 were born in 1956 to 1960, when the cause of this preventable condition had already been found.

Coloboma and developmental defects, including microphthalmia and aniridia, were associated with a family history of similar eye defect in 19 of the 82 children affected. Three were born premature (including one triplet) and one case was ascribed to maternal rubella.

Buphthalmos and glaucoma were among the most severe eye defects in partially sighted pupils; six children had a family history of the condition and two of the four girls were sisters.

Of the 20 children with hypermetropia and astigmatism, ten had a family history of visual defect.

Corneal lesions were familial in one girl and the other girl had keratitis from maternal infection by syphilis; post-natal infections in eight children were by

[page 30]

a variety of organisms and diseases; the case due to trauma was from a knife wound not penetrating further into the eye.

Uveitis and iridocyclitis occurred in six children with Still's disease.

Tumour of the eye was found in one boy whose father had been effectively treated in childhood.

Cerebral blindness was associated with encephalitis in one girl, fractured skull in two children and anoxia from trauma at birth in the fourth.

The one case of pseudoglioma was caused by a tapeworm from a dog; it was described in detail by Waldron Harris in 1961. (Brit. J. Oph., Vol. 45, No. 2, pp.144-146.)

One boy had a penetrating injury extending beyond the cornea.

Visual acuity and visual fields

According to the teachers, only 67 of the 1,374 children were making poor use of their available vision. Table 11 shows the visual acuity of each child in relation to the dominant handicap as assessed by the investigator.

Most of the boys and girls were considered to be correctly placed in schools and classes for partially sighted pupils, including 28 in whom the vision was recorded as less than 3/60 Snellen: in 17 of these there was no mention of visual fields, five had normal and six restricted fields of vision. Of the 487 with visual acuity of 3/60 - 6/60, fields were not mentioned in 253, were normal in 125 and restricted in 109; of the 471 with visual acuity of 6/36 - 6/24, fields were not mentioned in 247, were normal in 107 and restricted in 117; and of the 296 children with visual acuity of 6/18 or better, fields were known to be restricted in only 54.

Of the 49 children thought by the investigator to be more suitable for education as blind pupils, three had not had a conclusive visual assessment. The boy with perception of light only had retrolental fibroplasia, had one eye removed in infancy and was awaiting transfer to a school for the blind as his remaining eye had recently been injured. Of the other 45 pupils with visual acuity ranging from hand movements to 6/60, there was no mention of visual fields in the records of 25, five were normal and 15 restricted.

Thirty-six children with visual acuity of 6/18 or better were thought fit to attend ordinary schools.

Of the 27 children considered to be primarily educationally subnormal, three had visual acuity of 2/60 or less, nine were in the 3/60 - 6/60 range (four had restricted fields), six had visual acuity of 6/36 - 6/24 (three had restricted fields) and nine had visual acuity of 6/18 or better.

[page 31]

Table 11 Distribution of visual acuity in relation to dominant handicap

Of the 14 children thought to be primarily maladjusted, one had visual acuity of 3/60 - 6/60 and the other 13 were 6/18 or better.

Of the ten children thought to be primarily physically handicapped, only one of the four with visual acuity of 3/60 - 6/60 had restricted visual fields.

The visual acuity of the two delicate children was 6/18 or better; the epileptic boy with visual acuity of 2/60 or less had restricted fields.

One child was. considered to be unsuitable for education at school.

Children with multiple handicaps may be difficult to place and each has to be considered individually in relation to the most suitable school. Partial sight is usually considered the major handicap when visual acuity is 6/60 or less.

Schools previously attended

Table 12 shows the relationship of visual acuity to schools previously attended; there was a wide range of visual acuity whatever the previous educational history. Of the 392 children who had attended no other schools, 209 were in Group A and 183 in Group B.

Almost two-thirds of the children - 880, of whom 673 were in Group A and 207 in Group B - had previously attended sighted schools; 33 had visual acuity less than 3/60.

[page 32]

Relationship of visual acuity and previous schools

Of the 66 children who had previously attended other schools or classes for the partially sighted, 50 were in Group A and only 16 in Group B.

Of the 36 children transferred from schools for the blind, 29 were in Group A and seven in Group B; only three had visual acuity of less than 3/60, and some with comparatively good eyesight, including 17 with visual acuity of 6/36 or better, were thought to have been admitted to schools for the blind too precipitately.

Use of visual aids

Table 13 shows that 803 children (58 per cent) wore glasses for at least part of the time, but 476 used no visual aids of any kind, including 25 with myopia and two with hypermetropia and astigmatism, for whom it would be reasonable to think that glasses might have been helpful.

Low visual aids were used in a few schools and were well accepted by a small number of children whose visual defect was due to a variety of causes, especially cataract; five other children with this condition were helped by bifocal glasses. Contact lenses were supplied to 11 children. Hand lenses were occasionally used for close work by 36 children with no other visual aid, as well as by many of those using other aids.

In some children it was doubtful if the vision was improved much, if at all, by their use of glasses; sometimes, however, glasses had a protective function, as when tinted for albinism.

[page 33]

Table 13 Use of visual aids in relation to causes of partial sight

Mobility

Mobility other than good was classed as poor, whether it was due to visual defect or to an associated physical handicap. Table 14 gives details.

As visual acuity deteriorated so did mobility, ranging from one per cent of those with visual acuity of 6/18 or better to a maximum of 42 per cent of those with visual acuity of 2/60 or less. Mobility was, in aggregate, somewhat better in older than in younger children, and in boys than in girls; the overall percentages with poor mobility due to visual defect were 3.7 for older boys, 4.2 for older girls, 4.1 for younger boys and 10.8 for younger girls. It was surprising to find two older boys with visual acuity of 6/18 or better with poor mobility; this may have been associated with restricted visual fields.

Since so few children had poor mobility due to visual acuity of 2/60 or less, it would be misleading to draw any conclusions from the wide percentage difference between younger and older boys. Young children with obviously poor vision and poor mobility tend to be admitted in the first instance to schools for the blind, whereas a few older children with poor vision remain in schools and classes for the partially sighted despite poor mobility, either because of parental refusal to transfer or because they have been able, nevertheless, to benefit from the methods of education used for the partially sighted. Of the

[pages 34-35]

Table 14 Mobility related to visual acuity, years of birth and presence of a physical handicap in partially sighted children

Table 15 I.Q. test results in 567 children born in 1951, 1953 and 1955 related to causes of partial sight

[page 36]

69 children with visual acuity of 2/60 or less, 37 were considered to require placement in schools for the blind; they included most of the 18 children with poor mobility due to visual defect. Of those with visual acuity of 3/60 - 6/60, 28 had poor mobility, but only nine were thought to require education as blind pupils.

The visual acuity of those with poor mobility due to physical handicap showed a wide distribution, particularly in the older group; the younger physically handicapped children tend in the first instance to be admitted to special schools for the physically handicapped unless their visual acuity is obviously very poor. Of the 13 children with visual acuity 6/18 or better, five were thought to require placement in special schools for the physically handicapped.

An attempt was made to relate mobility to intelligence in the group of children born in 1951, 1953 and 1955 (Figure 3), but there were too few children for any conclusions to be drawn.

Intelligence

An Intelligence Quotient was obtained for 567 (over 95 per cent) of the 593 children born in 1951, 1953 and 1955, to provide a representative sample of the 1,374 children in the survey. Table 15 shows the range of intelligence in relation to the major clinical groups.

As mentioned earlier, the IQ distribution of subnormal or dull (50-84), average (85-114) and superior or gifted (115+) in the child population as a whole can be taken as approximately in the ratio of 15:70:15; in this sample of partially sighted children the ratio was 22:67:11. The greater proportion of dull, and the smaller proportion of gifted children in the special schools and classes for the partially sighted, reflect the ability of the more intelligent children with defective vision, particularly those with refractive errors, to manage well at ordinary schools.

When individual causes of visual defect were considered, interesting differences in the ratios were observed: over 15 per cent of the children with albinism, diseases of the retina and choroid, buphthalmos, uveitis and tumour of the eye were in the gifted range; the highest percentages of dull children were found among those with optic atrophy, myopia, nystagmus, cataract, retrolental fibroplasia, diseases of the retina and choroid and cerebral blindness.

Additional handicaps

Table 16 shows additional handicaps related to cause of visual defect. The standards adopted were explained in the discussion of Table 6 relating to additional handicaps in blind children. The total of 870 additional handicaps was spread among 560 partially sighted children: 39 per cent of older boys,

[page 37]

Figure 3

RELATIONSHIP OF INTELLIGENCE QUOTIENT TO MOBILITY OF CHILDREN BORN IN 1951, 1953 AND 1955 (Partially-sighted children)

40 per cent of older girls, 41 per cent of younger boys and 44 per cent of younger girls had additional handicaps or defects; of those affected, on average, older boys had 1.6, older girls 1.5, younger boys 1.4 and younger girls 1.6 additional handicaps per child.

Of the 1,374 children, 14.8 per cent were found to have significant physical disabilities, 12.9 per cent were of low intelligence, 11.9 per cent had speech or language difficulty, 7.3 per cent had evidence of maladjustment, 5.1 per cent were epileptic, 4.2 per cent had impaired hearing and eight per cent had other defects.

For children of both age groups, physical disability was the commonest additional handicap, comprising 23.4 per cent of handicaps in older and 22.4 per cent in younger children, closely followed by low intelligence with 19.6 per cent and 21.7 per cent respectively; speech and language difficulty came next with 18.5 per cent and 18.4 per cent respectively; hearing loss accounted for the relatively small percentages of 6.0 and 7.9 respectively of the defects.

[pages 38-39]

[page 40]

Low intelligence was particularly marked in children with cataract, optic atrophy and retrolental fibroplasia. Three of the four children with cerebral blindness had a total of eight additional handicaps, and a high relative proportion was found also in children with optic atrophy (161), retrolental fibroplasia (75) and developmental defects (82); a low proportion was found in children with albinism (141), while those with tumour of the eye, pseudoglioma and penetrating injury had none.

Mannerisms

Mannerisms are much less prevalent in the partially sighted than in the blind: in this survey 9.6 per cent of partially sighted, compared with 45 per cent of blind children, were affected. Mannerisms were present in 132 children, of whom 81 were in Group A and 51 in Group B, giving an incidence of 8.4 per cent in older and 12.3 per cent in younger children. Table 17 shows that they were found most often in those with cataract and optic atrophy. Of the total of 161 mannerisms, 23 were rocking, 19 head nodding, 18 hand-flapping, 15 eye poking, two twirling and 84 were other habits such as fidgeting and jerking, finger-sucking, nailbiting, grimacing and scratching.

Figure 4 relates mannerisms to intelligence for children born in 1951, 1953 and 1955; it shows a broadly similar distribution of Intelligence Quotients for those with and without mannerisms, but with proportionately more children in the 50-84 IQ range with one or more mannerisms.

Table 17 Mannerisms related to causes of partial sight and age group

[page 41]

Figure 4

RELATIONSHIP Of INTELLIGENCE QUOTIENT TO PRESENCE OF MANNERISMS IN CHILDREN BORN IN 1951,1953 AND 1955 (Partially-sighted children)

Attitudes of children, parents and teachers

These were examined and assessed in the same way as for the blind. Of the 1,374 partially sighted children, 644 boys and 451 girls had a satisfactory attitude in all respects, 70 boys and 22 girls had an unsatisfactory attitude to school, 41 boys and 28 girls to their handicap and 143 boys and 63 girls to other children, some having an unsatisfactory attitude in more than one respect.

Of the 139 boys and 72 girls with abnormal homes, 40 boys and 14 girls had unsatisfactory attitudes; and of the 328 boys and 176 girls whose parents had abnormal attitudes, 121 boys and 52 girls also had unsatisfactory attitudes.

Altogether, 192 boys were unsatisfactory in one or more respects; of these, 144 were considered by their teachers to be emotionally disturbed to an appreciable extent and 97 not working to capacity, whereas of 644 satisfactory boys, 152 were emotionally disturbed and 130 not working to capacity. Of 87 unsatisfactory girls, 61 were considered by their teachers to be emotionally

[page 42]

disturbed and 37 were not working to capacity, while of 451 satisfactory girls, 94 were emotionally disturbed and 74 not working to capacity.

In short, adverse home conditions and parental attitudes were inter-related with unsatisfactory attitudes in the children, and these were, in turn, reflected in their teachers' assessments of their emotional stability and educational progress. In all, 32 per cent were considered by their teachers to be emotionally disturbed. Even so, the development and educational progress of most of the 1,374 partially sighted children were satisfactory, as was also found in the survey of blind boys and girls.

Summary

1. A survey was made of 1,374 children in all schools and classes for partially sighted pupils in England and Wales.

2. The causes of visual defect were analysed in two groups: (A) those born in 1951 to 1955, and (B) those born in 1956 to 1960. Cataract was the chief cause in both groups, with myopia in second place for Group A.

3. Aetiology was studied: most conditions were of unknown aetiology; a genetic basis was the commonest known factor.

4. Visual acuity was recorded and the wide variation from perception of light to 6/18 Snellen or better was noted, with or without restriction of fields of vision. 1,233 of the children were thought to be suitably placed, but there were some doubts about 141:49 were considered blind, 36 suitable for ordinary sighted schools and the rest had other handicaps making appropriate placement difficult. An analysis of the previous schools attended showed that 880 children had come from sighted schools and 36 from schools for the blind.

5. The use of visual aids was investigated: 803 children were found to wear glasses, but 476 had no visual aid of any kind.

6. Mobility was related to visual acuity, to the presence of a physical handicap, to age, sex and, in a selected group, to intelligence. It was poorer with diminished visual acuity, in younger than in older children and in girls than in boys, but no definite relationship with intelligence was shown.

7. Intelligence Quotients were obtained for children born in 1951, 1953 and 1955 and compared in the major clinical groups: children with albinism, diseases of the retina and choroid, buphthalmos, uveitis and tumour of the eye tended to be in the more intelligent, and those with cataract, myopia, optic atrophy and nystagmus in the less intelligent groups.

8. Additional handicaps were collated and compared for Groups A and B: in both, physical disability was the commonest additional handicap, followed

[page 43]

by low intelligence and speech and language difficulties. Those with cerebral blindness, optic atrophy, retrolental fibroplasia and developmental defects were the most handicapped.

9. Mannerisms were noted in 9.6 per cent of the children, being more prevalent in those with cataract and optic atrophy, in the younger children and in those below average intelligence.

10. The relationship between home and parents' and children's attitudes was examined and the effect of these on the assessment by teachers noted. Adverse home conditions and parental attitudes were reflected in the children's attitudes, emotional stability and educational progress.

11. No fewer than 32 per cent of the children were considered by their teachers to be emotionally disturbed. As with blind children, there was need for psychological and psychiatric investigation.