Documenta Ophthalmologica 82: 15-23, 1992. 9 1992 Kluwer Academic Publishers. Printed in the Netherlands.
The Visual Advice Centre, Eindhoven, The Netherlands An intervenient evaluation J . J . N E V E , 1'2 W.E.M. KORTEN, 1'3 F.F. JORRITSMA, 1 G.F. KINDS 1'4'5'6 & Ch.P. LEGEIN 2'7 ~The Visual Advice Centre, Eindhoven; 2Institutefor Perception Research, Eindhoven; 3Department of Ophthahnology, St. Joseph Hospital, Veldhoven; 4Department of Ophthalmology, Academic Hospital, Utrecht; 5Bartimeus, Zeist; 6Bartimeushage, Doom; 7Department of Ophthalmology, Catharina Hospital, Eindhoven, The Netherlands Accepted 1 September 1992
Key words: Low vision aids, Success rate, Visual assessment, Visual impairment Abstract. On referral by ophthalmologists, the Visual Advice Centre provides the partially sighted with advice and prescriptions for illumination and visual aids. In this paper the multidisciplinary structure of the centre is presented and the results obtained in the first 18 months of its existence are discussed. Two hundred and ninety-eight patients were referred to the centre in this period. The majority of these patients (79.2%) were older than 60 years. The main cause of visual impairment was macular disease (45.3% of the patients). An interesting finding is that, although reading is an important need, reading problems only constituted 35.9% of the total number of demands for help. From an inquiry into the situation ol 125 patients 6 months after prescription, it appears that more than 90% of the aids prescribed are used regularly. The conclusion is drawn that patients referred to the Visual Advice Centre benefit from the multi-disciplinary approach to their problems.
Introduction The Visual Advice Centre Eindhoven (VAC-E), a non-profit low vision centre, was opened in September 1990. On referral by local opthalmologists the centre provides the partially sighted with advice and prescriptions for low vision aids and illumination, on the basis of an examination of their residual visual abilities and their individual needs. The centre was established in consultation with ophthalmologists from clinics in and around Eindhoven, and operates in close collaboration with local institutes specialised in psychosocial support and ADL-therapy. The VAC aims at improving the care of the partially sighted in Eindhoven and hopes to contribute to the development of directives for future implementation of VAC-like activities in the field of low vision elsewhere. In the context of low vision care for the elderly, the VAC model and methods can be regarded as experimental in the Netherlands. The centre is being financed for a period of 3 years by the Praeventiefonds, a Dutch organisation for preventive medicine. In these years the structure and
16 methods of the centre and its contribution to low vision care in Eindhoven will be evaluated. The results of this evaluation will be presented at the end of 1993. The purpose of this article is to briefly describe the structure and to give an account of the results obtained in the first 18 months of low vision care at the VAC.
The VAC model
The VAC has a multi-disciplinary (part-time) staff t h a t consists of two psychophysicists, a senior ophthalmic assistant/optometrist, two junior ophthalmic assistants, an ergotherapist, a social worker, a consultant ophthalmologist and a secretary. The centre is open for two days a week. The diagram in Fig. 1 illustrates the structure of the centre from the patient's point of view. Patients are referred to the low vision centre by their ophthalmologist, who provides the centre with the essential medical information on the patient. In a first visit to the VAC the history of the patient is noted, his or her visual needs are assessed and a clinical and psychophysical examination is carried out. This examination may include refraction, measurement of the far and near visual acuity at different levels of illumination, and examination of binocular vision, intra-ocular glare, contrast sensitivity, colour vision, visual fields (perimetry) and dark adaptation. On a second visit tests are performed with a number of low vision aids, depending on the patient's visual needs and the results of the examinations. As a rule general information and advice on illumination, ADL-activities and mobility are also given during this second visit. The first and second visits take about two and a half hours and one hour, respectively. If an aid is found to be suitable it is, as far as possible, lent to the patient for a trial period in the patient's own environment for at least two weeks. If indicated, the ergotherapist and/or the social worker may visit the patient in this period. Home visits enable the ergotherapist to give instructions and training in the use of the aids, to check the illumination in the patient's home and to answer other relevant questions raised by the patient. In a home visit the social worker provides information on, for instance, legal regulations and social insurance, discusses problems concerning the acceptance of the handicap or the use of a low vision aid, and assesses whether referral for more extensive psychosocial support is indicated. After this period the patient revisits the VAC for assessment of the trial with the loaned visual aids. This visit takes about one hour. If the trial with the loaned aids was not successful, supplementary measurements, tests and a second trial period are considered. A definitive
17 Patient
Referring ophthalmologist
Visual Advice Centre
I -
FIRST VISIT - history assessmentof needs measurements
~9[--
-
SECOND VISIT test with aids
-411--
-
trial period of aids home visit ergotherapist home visit social worker
'
THIRDVISIT appraisalof trial period
-q-
....
Definitive advice and prescription
Referring ophthalmologist
..............
Optician
Insurance company
Inquiry by telephone after 6 months
Fig. 1. The structure of the Visual Advice Centre from the patient's point of view.
prescription follows when the trial has been successful. This prescription is implemented by local opticians. Finally, a comprehensive report is sent to the referring ophthalmologist, the family doctor and the insurance company concerned. Patients are encouraged to contact the centre whenever they wish. In addition, six months after prescription they are contacted by telephone to inquire into possible changes in their eye condition, their actual use of the prescribed visual aids, and their satisfaction with the advice received. On the
18 grounds of this inquiry patients may be advised to visit the VAC or their ophthalmologist again.
Patients
In the period from September 1990 to February 1992 a total of 298 patients were referred to the VAC by their ophthalmologists. Before their first visit to the centre 16 patients (5.4%) died or stated that they did not want a low vision examination, thus 282 patients paid at least one visit to the centre. Four patients (1.3%) died or withdrew from further examination after the first visit, and 11 patients (3.7%) withdrew after the second visit. Thus a total of 267 patients visited the centre, were examined, provided with low vision aids on trial, and given a definitive advice or prescription. With 125 of these patients (46.8%) an inquiry by telephone was held six months after the definitive prescription or advice.
Results
In the total group of 298 referred patients 186 were female (62.4%) and 112 male (37.6%). The mean age at the time of the first visit was 74 years for the women and 65 years for the men. Two hundred and thirty-six patients (79.2%) were older than 60 years. The distribution by age is given in Table 1. The main causes of visual impairment, as indicated by the referring ophthalmologists, were macular disorders (45.3%), diabetic retinopathy (12.8%), glaucoma (9.4%), severe myopia (5.4%), TRD (4.7%), optic atrophy (3.7%), cataract (3.4%), vascular retinal diseases (3.2%) and corneal diseases (3.0%). Table 2 shows the distance visual acuity of the best eye at the first visit to the centre for the 267 patients who were given a definitive advice or prescription. Table 1. Age distribution of 298 patients referred to the centre Age (years)
Number of patients
Percentage
11- 20 21- 30 31- 40 41- 50 51- 60 61- 70 71- 80 81- 90 91-100
5 12 13 18 14 36 101 91 8
1.7% 4.0% 4.4% 6.0% 4.7% 12.1% 33.9% 30.5% 2.7%
Total
298
100%
19 In order to provide the appropriate care and low vision appliances to the patients it is important to know their needs and wishes. Table 3 gives a classification of the kinds of activities and tasks for which the patients asked assistance. The data refer to the 267 patients who received a definitive advice or prescription. A total of 642 demands for help were counted. It is clear from this table that for most of the patients (86%) reading (or improved reading) is an important need. It should be stressed, however, that reading is certainly not the only activity or task they want to be helped with. This is made clear in Fig. 2, that shows the proportional distribution of the specified demands for help. Table 4 lists the number of low vision aids given on trial and prescribed for the above 267 patients. We classify any device which enables a low vision patient to improve his visual functioning as a low vision aid. Therefore this includes such devices as task illumination, tints, sideshields, magnifying software, enlarged computerscreens, small reading-tables, concept-holders and bedprisms, as well as the more conventional aids like magnifiers, telescopes and CCTV's. As is usually found in low vision rehabilitation, many patients require more than one aid to assist them in various tasks. At least 396 aids were loaned and 411 aids were prescribed to the 267 patients. It should be noticed that, on account of the cost, the VAC collection of loaned aids does not include CCTV's. CCTV's are provided by most Table 2. Distance visual acuity of best eye at patient's first visit Visual acuity (v.a.) v.a. 0.05 0.10 0.20 0.30 0.40 v.a.
~< 0.05 < v.a. < v.a. < v.a. < v.a. < v.a. >0.50
~ 0.10 40.20 ~ 0.30 ~ 0.40 ~0.50
Total
Number 45 36 61 55 34 18 18 267
Percentage 16.9% 13.5% 22.9% 20.6% 12.7% 6.7% 6.7% 100%
Table 3. Number of patients asking assistance for the specified activities and tasks. The percentage is calculated over 267 patients Activities and tasks
Number
Percentage
Reading Writing Needlework etc. Intermediate distance TV-watching Mobility Other
230 39 59 63 72 37 142
86.1% 14.6% 22.1% 23.6% 27.0% 13.9% 53.2%
Total
642
20
(35.9%) F
E ,%)
Fig. 2. The proportional distribution of the demands for help. The characters correspond to
reading (A), writing (B), needlework etc. (C), tasks at intermediate distance (D), watching television (E), mobility (F), and other (G).
Table 4. Numbers of low vision aids given on trial and prescribed for 267 patients. The glasses given on trial were reading glasses, the prescribed glasses also include distance glasses. CCTV's were not loaned during the trial period
Low Vision Aids (LVA) Glasses Magnifiers Magnifying lamps Telescopes PL-task illumination Tints / sideshields CCTV's Other Total
On Trial
Prescribed
29 97 64 28 90 32 1 55
78 67 34 18 70 21 59 64
396
411
Rejected 30.1% 46.9% 35.7% 22.2% 34.5%
insurance companies on p e r m a n e n t loan. Fifty-nine C C T V ' s were prescribed. In 12 cases (20.3%), however, these C C T V ' s were prescribed to replace worn-out or ergonomically inadequate television magnifiers. The loaned spectacles are merely reading glasses with powers up to 12 diopters and built-in prisms up to 14 diopters. The n u m b e r of pairs of spectacles prescribed greatly exceeds the n u m b e r loaned. This is due to the fact that the f o r m e r n u m b e r also includes distance glasses. T h e column labelled 'rejected' gives the percentage of aids on trial that turned out to be inadequate to m e e t the patients needs and wishes. Six months after the definitive advice or prescription patients are contacted by telephone to inquire into their visual functioning and their use of the prescribed aids. The aim of this inquiry is to keep in contact with the patients for a longer period and to find out whether they need further assistance. O n e hundred and thirty-three (49.8%) of the 267 patients were
21 contacted in this way up to February 1992, of whom 6 (2.3%) died before the inquiry and 2 (0.08%) did not follow our advice or prescription. The remaining 125 patients were asked to indicate the frequency with which they used their aids, to scale their appreciation of the aid on a five point scale (very good, good, moderate, poor, useless) and to comment upon any problem concerning the use of the aid. Table 5 lists the frequencies of use for the separate classes of aids. As can be seen from this table 80.5% of the aids prescribed to this group of patients are used every day and 10.1% frequently. In Table 6 the patient's appreciation of the aids is listed. The figures give the percentages of the total number of the specific aids indicated. The appreciation of the aids (very good/good/ moderate for 81.8% of the aids) agrees quite well with the frequency of use of the aids (daily/frequently for 90.5% of the aids). From the inquiry by telephone with the 125 patients it appears that 55.4% of the aids are used without problems. Of the problems encountered, 13.5% is indicated by the patients as being related to growing mental, visual or physical problems, 14.9% is of a technical nature or inherent in the aid (weight, field of view etc.), 6.8% is related to the particular tasks the patients want to perform and 9.4% of the problems is unclear. Table 5. F r e q u e n c i e s of use of the p r e s c r i b e d aids b y 125 p a t i e n t s , six m o n t h s after p r e s c r i p t i o n (in % ) L o w V i s i o n A i d s (LVA)
Daily
Frequently
Seldom
Glasses Magnifiers Magnifying lamps Telescopes PL-task illumination Tints/sideshields CCTV's Other
90.6 76.0 82.6 63.6 75.0 16.7 96.8 75.0
3.1 16.0 4.4 27.3 6.3 83.3 -
3.1 13.0 -
Total
80.5
10.1
2.7
Never 6.2 8.0
Unknown
9.1 12.5 3.2 25.0
6.2 -
6.0
0.7
-
Table 6. S u b j e c t i v e a p p r e c i a t i o n of the aids b y 125 p a t i e n t s , six m o n t h s a f t e r p r e s c r i p t i o n (in % ) L o w V i s i o n A i d s (LVA)
Very g o o d
Good
Moderate
Poor
Useless
Unknown
Glasses Magnifiers Magnifying lamps Telescopes PL-task illumination Tints/sideshields CCTV's Other
24.2 44.0 26.1 54.6 12.5 33.3 33.3 25.0
45.5 28.0 43.5 36.4 62.5 66.7 46.7 50.0
18.2 16.0 8.7 . 13.3 -
9.1 4.0 13.0 6.3
12.5
3,0 8.0 8.7 9.1 6.3
3.3
25.0
3.3 -
Total
31.1
44.6
10.8
6.1
2.0
5.4
.
.
. -
22 Discussion
The distribution by age (and sex) of patients, as given in Table 1, was found to be quite similar to other retrospective studies concerning low vision care in developed countries [1-4]. A survey of the statistics on 6755 patients from the Lighthouse Low Vision Services, for instance, indicate that 77% of their patients are 65 years or older, while 60% were female [4]. In our group of patients 79.2% is older than 60 years and 62.4% is female. It is important to realize that the majority of the patients at low vision centres are elderly. This means that other factors than vision, such as mental and physical health and the ergonomical aspects of tasks and appliances, also have to be taken into consideration. The main cause of visual impairment in our patients, as indicated by the referring ophthalmologists, is macular disease (45.3%). Although the percentages for the other main causes are somewhat different from the figures given in similar studies [1, 4, 5], we may conclude that our results are in broad agreement. The most common combination of pathologies was cataract in association with an age-related maculopathy. This is plausible, given the reluctance of the referring ophthalmologists to extract cataracts in the presence of macular changes. According to the W H O standards, 16.9% of our patients were blind (visual acuity 0.30. These patients had a variety of problems, such as not being able to read the newspaper with ordinary glasses, severely restricted fields, unobserved binocular problems, severe sensitivity to glare, and mental deterioration or physical handicaps accompanied by visual problems. It is clear that a definition of partial sightedness based on the residual visual acuity, such as having an acuity less than 0.3, is too limited. In our view it is better to give a wider definition of a low vision patient. Such a definition is given, for instance, by Faye [4], according to whom the low vision patient is a person with an eye disorder whose visual performance is decreased as a consequence of reduced visual acuity, abnormal visual field, reduced contrast sensitivity, or other ocular dysfunctions that prevent performance to full capacity as compared to a normal person of the same age and sex. Although reading and watching television are important needs (86% and 27% of the patients, respectively), patients certainly have a variety of other tasks they also want to perform (again). Therefore it is of great importance to assess thoroughly, together with the patient, his general situation regarding family, work, reading needs, other visual needs, hobbies and so on. The entire situation of the patient is important. When people become visually handicapped they become vulnerable and meet various kinds of ergonomical, physical, psychological and social problems. This is also reflected in the number of cases for whom assistance from our er-
23 gotherapist (48.3% of all patients) and social worker (17.5% of all patients) was needed. The rather high percentages for rejection of magnifiers, magnifying lamps, telescopes and tints after a trial-period at home, give support to the opinion that successful use of an aid in a clinical setting does not guarantee the usefulness of that aid at home [6]. In our experience, clear ergonomical and users' instructions, additional training and loan of the aids for a trial period at home, are important aspects of the successful prescription of low vision aids. The inquiry six months after prescription shows that more than 90% of the aids are used regularly and over 80% of the aids are assessed as moderate to very good. Success in prescribing low vision aids is often expressed as regular and successful use of the aids [1, 7, 8] and, as in our inquiry, is often based mainly on the patient's own judgement. From that point of view our results are quite encouraging. In default of more objective measures it is difficult, however, to make a fair comparison with success rates from other studies [9] since many parameters are involved. The criteria for referral, the definition of success, the distribution of age and initial visual acuity, etc., may differ. In summary we may conclude that this survey of 18 months of low vision care at the Visual Advice Centre confirms our initial idea that, when prescribing low vision aids, patients will benefit from a multi-disciplinary approach to their problems. References 1. Van Rens GHMB, Chmielowski RJM, Lemmens WAJG. Results obtained with low vision aids. Doc Ophthalmol 1991; 78: 205-10. 2. Sanderson GF, Cumming AE, Polkinghorne PJ. A hospital renting system for low vision aids. Austral New Zeal J Ophthalmol 1986; 14: 359-63. 3. Dowie AT. Management and practice of low visual acuity. London: The Eastern Press, 1988. 4. Faye EE. Clinical low vision. Boston/Toronto: Little, Brown and Company, 1984. 5. Silver JH. Low vision aids in the management of visual handicap. Br J Physiol Optics 1976; 31: 47-87. 6. Neve JJ, Melotte HEM. Visual aids. In: Silver JH, ed. The management of low vision. Guildford: Butterworth and Heinemann, in press. 7. Freudenberger HJ, Robbins I. Characteristics of acceptance and rejection. Am J Ophthaltool 1959; 47: 582-84. 8. Boulton JM. Results of three years of low vision care at Palmerston North Hospital. Trans Ophthalmol Soc NZ 1979; 31: 27-31. 9. Nilsson UL. Results of low vision rehabilitation [PhD-thesis]. Link6ping: University Medical Dissertation, No. 313, 1990.
Address for correspondence: Dr Ir J.J. Neve, Visual Advice Centre, Paradijslaan 40, 5611 KP Eindhoven, The Netherlands. Phone: +31-40-455 253.
The Visual Advice Centre, Eindhoven, The Netherlands An intervenient evaluation J . J . N E V E , 1'2 W.E.M. KORTEN, 1'3 F.F. JORRITSMA, 1 G.F. KINDS 1'4'5'6 & Ch.P. LEGEIN 2'7 ~The Visual Advice Centre, Eindhoven; 2Institutefor Perception Research, Eindhoven; 3Department of Ophthahnology, St. Joseph Hospital, Veldhoven; 4Department of Ophthalmology, Academic Hospital, Utrecht; 5Bartimeus, Zeist; 6Bartimeushage, Doom; 7Department of Ophthalmology, Catharina Hospital, Eindhoven, The Netherlands Accepted 1 September 1992
Key words: Low vision aids, Success rate, Visual assessment, Visual impairment Abstract. On referral by ophthalmologists, the Visual Advice Centre provides the partially sighted with advice and prescriptions for illumination and visual aids. In this paper the multidisciplinary structure of the centre is presented and the results obtained in the first 18 months of its existence are discussed. Two hundred and ninety-eight patients were referred to the centre in this period. The majority of these patients (79.2%) were older than 60 years. The main cause of visual impairment was macular disease (45.3% of the patients). An interesting finding is that, although reading is an important need, reading problems only constituted 35.9% of the total number of demands for help. From an inquiry into the situation ol 125 patients 6 months after prescription, it appears that more than 90% of the aids prescribed are used regularly. The conclusion is drawn that patients referred to the Visual Advice Centre benefit from the multi-disciplinary approach to their problems.
Introduction The Visual Advice Centre Eindhoven (VAC-E), a non-profit low vision centre, was opened in September 1990. On referral by local opthalmologists the centre provides the partially sighted with advice and prescriptions for low vision aids and illumination, on the basis of an examination of their residual visual abilities and their individual needs. The centre was established in consultation with ophthalmologists from clinics in and around Eindhoven, and operates in close collaboration with local institutes specialised in psychosocial support and ADL-therapy. The VAC aims at improving the care of the partially sighted in Eindhoven and hopes to contribute to the development of directives for future implementation of VAC-like activities in the field of low vision elsewhere. In the context of low vision care for the elderly, the VAC model and methods can be regarded as experimental in the Netherlands. The centre is being financed for a period of 3 years by the Praeventiefonds, a Dutch organisation for preventive medicine. In these years the structure and
16 methods of the centre and its contribution to low vision care in Eindhoven will be evaluated. The results of this evaluation will be presented at the end of 1993. The purpose of this article is to briefly describe the structure and to give an account of the results obtained in the first 18 months of low vision care at the VAC.
The VAC model
The VAC has a multi-disciplinary (part-time) staff t h a t consists of two psychophysicists, a senior ophthalmic assistant/optometrist, two junior ophthalmic assistants, an ergotherapist, a social worker, a consultant ophthalmologist and a secretary. The centre is open for two days a week. The diagram in Fig. 1 illustrates the structure of the centre from the patient's point of view. Patients are referred to the low vision centre by their ophthalmologist, who provides the centre with the essential medical information on the patient. In a first visit to the VAC the history of the patient is noted, his or her visual needs are assessed and a clinical and psychophysical examination is carried out. This examination may include refraction, measurement of the far and near visual acuity at different levels of illumination, and examination of binocular vision, intra-ocular glare, contrast sensitivity, colour vision, visual fields (perimetry) and dark adaptation. On a second visit tests are performed with a number of low vision aids, depending on the patient's visual needs and the results of the examinations. As a rule general information and advice on illumination, ADL-activities and mobility are also given during this second visit. The first and second visits take about two and a half hours and one hour, respectively. If an aid is found to be suitable it is, as far as possible, lent to the patient for a trial period in the patient's own environment for at least two weeks. If indicated, the ergotherapist and/or the social worker may visit the patient in this period. Home visits enable the ergotherapist to give instructions and training in the use of the aids, to check the illumination in the patient's home and to answer other relevant questions raised by the patient. In a home visit the social worker provides information on, for instance, legal regulations and social insurance, discusses problems concerning the acceptance of the handicap or the use of a low vision aid, and assesses whether referral for more extensive psychosocial support is indicated. After this period the patient revisits the VAC for assessment of the trial with the loaned visual aids. This visit takes about one hour. If the trial with the loaned aids was not successful, supplementary measurements, tests and a second trial period are considered. A definitive
17 Patient
Referring ophthalmologist
Visual Advice Centre
I -
FIRST VISIT - history assessmentof needs measurements
~9[--
-
SECOND VISIT test with aids
-411--
-
trial period of aids home visit ergotherapist home visit social worker
'
THIRDVISIT appraisalof trial period
-q-
....
Definitive advice and prescription
Referring ophthalmologist
..............
Optician
Insurance company
Inquiry by telephone after 6 months
Fig. 1. The structure of the Visual Advice Centre from the patient's point of view.
prescription follows when the trial has been successful. This prescription is implemented by local opticians. Finally, a comprehensive report is sent to the referring ophthalmologist, the family doctor and the insurance company concerned. Patients are encouraged to contact the centre whenever they wish. In addition, six months after prescription they are contacted by telephone to inquire into possible changes in their eye condition, their actual use of the prescribed visual aids, and their satisfaction with the advice received. On the
18 grounds of this inquiry patients may be advised to visit the VAC or their ophthalmologist again.
Patients
In the period from September 1990 to February 1992 a total of 298 patients were referred to the VAC by their ophthalmologists. Before their first visit to the centre 16 patients (5.4%) died or stated that they did not want a low vision examination, thus 282 patients paid at least one visit to the centre. Four patients (1.3%) died or withdrew from further examination after the first visit, and 11 patients (3.7%) withdrew after the second visit. Thus a total of 267 patients visited the centre, were examined, provided with low vision aids on trial, and given a definitive advice or prescription. With 125 of these patients (46.8%) an inquiry by telephone was held six months after the definitive prescription or advice.
Results
In the total group of 298 referred patients 186 were female (62.4%) and 112 male (37.6%). The mean age at the time of the first visit was 74 years for the women and 65 years for the men. Two hundred and thirty-six patients (79.2%) were older than 60 years. The distribution by age is given in Table 1. The main causes of visual impairment, as indicated by the referring ophthalmologists, were macular disorders (45.3%), diabetic retinopathy (12.8%), glaucoma (9.4%), severe myopia (5.4%), TRD (4.7%), optic atrophy (3.7%), cataract (3.4%), vascular retinal diseases (3.2%) and corneal diseases (3.0%). Table 2 shows the distance visual acuity of the best eye at the first visit to the centre for the 267 patients who were given a definitive advice or prescription. Table 1. Age distribution of 298 patients referred to the centre Age (years)
Number of patients
Percentage
11- 20 21- 30 31- 40 41- 50 51- 60 61- 70 71- 80 81- 90 91-100
5 12 13 18 14 36 101 91 8
1.7% 4.0% 4.4% 6.0% 4.7% 12.1% 33.9% 30.5% 2.7%
Total
298
100%
19 In order to provide the appropriate care and low vision appliances to the patients it is important to know their needs and wishes. Table 3 gives a classification of the kinds of activities and tasks for which the patients asked assistance. The data refer to the 267 patients who received a definitive advice or prescription. A total of 642 demands for help were counted. It is clear from this table that for most of the patients (86%) reading (or improved reading) is an important need. It should be stressed, however, that reading is certainly not the only activity or task they want to be helped with. This is made clear in Fig. 2, that shows the proportional distribution of the specified demands for help. Table 4 lists the number of low vision aids given on trial and prescribed for the above 267 patients. We classify any device which enables a low vision patient to improve his visual functioning as a low vision aid. Therefore this includes such devices as task illumination, tints, sideshields, magnifying software, enlarged computerscreens, small reading-tables, concept-holders and bedprisms, as well as the more conventional aids like magnifiers, telescopes and CCTV's. As is usually found in low vision rehabilitation, many patients require more than one aid to assist them in various tasks. At least 396 aids were loaned and 411 aids were prescribed to the 267 patients. It should be noticed that, on account of the cost, the VAC collection of loaned aids does not include CCTV's. CCTV's are provided by most Table 2. Distance visual acuity of best eye at patient's first visit Visual acuity (v.a.) v.a. 0.05 0.10 0.20 0.30 0.40 v.a.
~< 0.05 < v.a. < v.a. < v.a. < v.a. < v.a. >0.50
~ 0.10 40.20 ~ 0.30 ~ 0.40 ~0.50
Total
Number 45 36 61 55 34 18 18 267
Percentage 16.9% 13.5% 22.9% 20.6% 12.7% 6.7% 6.7% 100%
Table 3. Number of patients asking assistance for the specified activities and tasks. The percentage is calculated over 267 patients Activities and tasks
Number
Percentage
Reading Writing Needlework etc. Intermediate distance TV-watching Mobility Other
230 39 59 63 72 37 142
86.1% 14.6% 22.1% 23.6% 27.0% 13.9% 53.2%
Total
642
20
(35.9%) F
E ,%)
Fig. 2. The proportional distribution of the demands for help. The characters correspond to
reading (A), writing (B), needlework etc. (C), tasks at intermediate distance (D), watching television (E), mobility (F), and other (G).
Table 4. Numbers of low vision aids given on trial and prescribed for 267 patients. The glasses given on trial were reading glasses, the prescribed glasses also include distance glasses. CCTV's were not loaned during the trial period
Low Vision Aids (LVA) Glasses Magnifiers Magnifying lamps Telescopes PL-task illumination Tints / sideshields CCTV's Other Total
On Trial
Prescribed
29 97 64 28 90 32 1 55
78 67 34 18 70 21 59 64
396
411
Rejected 30.1% 46.9% 35.7% 22.2% 34.5%
insurance companies on p e r m a n e n t loan. Fifty-nine C C T V ' s were prescribed. In 12 cases (20.3%), however, these C C T V ' s were prescribed to replace worn-out or ergonomically inadequate television magnifiers. The loaned spectacles are merely reading glasses with powers up to 12 diopters and built-in prisms up to 14 diopters. The n u m b e r of pairs of spectacles prescribed greatly exceeds the n u m b e r loaned. This is due to the fact that the f o r m e r n u m b e r also includes distance glasses. T h e column labelled 'rejected' gives the percentage of aids on trial that turned out to be inadequate to m e e t the patients needs and wishes. Six months after the definitive advice or prescription patients are contacted by telephone to inquire into their visual functioning and their use of the prescribed aids. The aim of this inquiry is to keep in contact with the patients for a longer period and to find out whether they need further assistance. O n e hundred and thirty-three (49.8%) of the 267 patients were
21 contacted in this way up to February 1992, of whom 6 (2.3%) died before the inquiry and 2 (0.08%) did not follow our advice or prescription. The remaining 125 patients were asked to indicate the frequency with which they used their aids, to scale their appreciation of the aid on a five point scale (very good, good, moderate, poor, useless) and to comment upon any problem concerning the use of the aid. Table 5 lists the frequencies of use for the separate classes of aids. As can be seen from this table 80.5% of the aids prescribed to this group of patients are used every day and 10.1% frequently. In Table 6 the patient's appreciation of the aids is listed. The figures give the percentages of the total number of the specific aids indicated. The appreciation of the aids (very good/good/ moderate for 81.8% of the aids) agrees quite well with the frequency of use of the aids (daily/frequently for 90.5% of the aids). From the inquiry by telephone with the 125 patients it appears that 55.4% of the aids are used without problems. Of the problems encountered, 13.5% is indicated by the patients as being related to growing mental, visual or physical problems, 14.9% is of a technical nature or inherent in the aid (weight, field of view etc.), 6.8% is related to the particular tasks the patients want to perform and 9.4% of the problems is unclear. Table 5. F r e q u e n c i e s of use of the p r e s c r i b e d aids b y 125 p a t i e n t s , six m o n t h s after p r e s c r i p t i o n (in % ) L o w V i s i o n A i d s (LVA)
Daily
Frequently
Seldom
Glasses Magnifiers Magnifying lamps Telescopes PL-task illumination Tints/sideshields CCTV's Other
90.6 76.0 82.6 63.6 75.0 16.7 96.8 75.0
3.1 16.0 4.4 27.3 6.3 83.3 -
3.1 13.0 -
Total
80.5
10.1
2.7
Never 6.2 8.0
Unknown
9.1 12.5 3.2 25.0
6.2 -
6.0
0.7
-
Table 6. S u b j e c t i v e a p p r e c i a t i o n of the aids b y 125 p a t i e n t s , six m o n t h s a f t e r p r e s c r i p t i o n (in % ) L o w V i s i o n A i d s (LVA)
Very g o o d
Good
Moderate
Poor
Useless
Unknown
Glasses Magnifiers Magnifying lamps Telescopes PL-task illumination Tints/sideshields CCTV's Other
24.2 44.0 26.1 54.6 12.5 33.3 33.3 25.0
45.5 28.0 43.5 36.4 62.5 66.7 46.7 50.0
18.2 16.0 8.7 . 13.3 -
9.1 4.0 13.0 6.3
12.5
3,0 8.0 8.7 9.1 6.3
3.3
25.0
3.3 -
Total
31.1
44.6
10.8
6.1
2.0
5.4
.
.
. -
22 Discussion
The distribution by age (and sex) of patients, as given in Table 1, was found to be quite similar to other retrospective studies concerning low vision care in developed countries [1-4]. A survey of the statistics on 6755 patients from the Lighthouse Low Vision Services, for instance, indicate that 77% of their patients are 65 years or older, while 60% were female [4]. In our group of patients 79.2% is older than 60 years and 62.4% is female. It is important to realize that the majority of the patients at low vision centres are elderly. This means that other factors than vision, such as mental and physical health and the ergonomical aspects of tasks and appliances, also have to be taken into consideration. The main cause of visual impairment in our patients, as indicated by the referring ophthalmologists, is macular disease (45.3%). Although the percentages for the other main causes are somewhat different from the figures given in similar studies [1, 4, 5], we may conclude that our results are in broad agreement. The most common combination of pathologies was cataract in association with an age-related maculopathy. This is plausible, given the reluctance of the referring ophthalmologists to extract cataracts in the presence of macular changes. According to the W H O standards, 16.9% of our patients were blind (visual acuity 0.30. These patients had a variety of problems, such as not being able to read the newspaper with ordinary glasses, severely restricted fields, unobserved binocular problems, severe sensitivity to glare, and mental deterioration or physical handicaps accompanied by visual problems. It is clear that a definition of partial sightedness based on the residual visual acuity, such as having an acuity less than 0.3, is too limited. In our view it is better to give a wider definition of a low vision patient. Such a definition is given, for instance, by Faye [4], according to whom the low vision patient is a person with an eye disorder whose visual performance is decreased as a consequence of reduced visual acuity, abnormal visual field, reduced contrast sensitivity, or other ocular dysfunctions that prevent performance to full capacity as compared to a normal person of the same age and sex. Although reading and watching television are important needs (86% and 27% of the patients, respectively), patients certainly have a variety of other tasks they also want to perform (again). Therefore it is of great importance to assess thoroughly, together with the patient, his general situation regarding family, work, reading needs, other visual needs, hobbies and so on. The entire situation of the patient is important. When people become visually handicapped they become vulnerable and meet various kinds of ergonomical, physical, psychological and social problems. This is also reflected in the number of cases for whom assistance from our er-
23 gotherapist (48.3% of all patients) and social worker (17.5% of all patients) was needed. The rather high percentages for rejection of magnifiers, magnifying lamps, telescopes and tints after a trial-period at home, give support to the opinion that successful use of an aid in a clinical setting does not guarantee the usefulness of that aid at home [6]. In our experience, clear ergonomical and users' instructions, additional training and loan of the aids for a trial period at home, are important aspects of the successful prescription of low vision aids. The inquiry six months after prescription shows that more than 90% of the aids are used regularly and over 80% of the aids are assessed as moderate to very good. Success in prescribing low vision aids is often expressed as regular and successful use of the aids [1, 7, 8] and, as in our inquiry, is often based mainly on the patient's own judgement. From that point of view our results are quite encouraging. In default of more objective measures it is difficult, however, to make a fair comparison with success rates from other studies [9] since many parameters are involved. The criteria for referral, the definition of success, the distribution of age and initial visual acuity, etc., may differ. In summary we may conclude that this survey of 18 months of low vision care at the Visual Advice Centre confirms our initial idea that, when prescribing low vision aids, patients will benefit from a multi-disciplinary approach to their problems. References 1. Van Rens GHMB, Chmielowski RJM, Lemmens WAJG. Results obtained with low vision aids. Doc Ophthalmol 1991; 78: 205-10. 2. Sanderson GF, Cumming AE, Polkinghorne PJ. A hospital renting system for low vision aids. Austral New Zeal J Ophthalmol 1986; 14: 359-63. 3. Dowie AT. Management and practice of low visual acuity. London: The Eastern Press, 1988. 4. Faye EE. Clinical low vision. Boston/Toronto: Little, Brown and Company, 1984. 5. Silver JH. Low vision aids in the management of visual handicap. Br J Physiol Optics 1976; 31: 47-87. 6. Neve JJ, Melotte HEM. Visual aids. In: Silver JH, ed. The management of low vision. Guildford: Butterworth and Heinemann, in press. 7. Freudenberger HJ, Robbins I. Characteristics of acceptance and rejection. Am J Ophthaltool 1959; 47: 582-84. 8. Boulton JM. Results of three years of low vision care at Palmerston North Hospital. Trans Ophthalmol Soc NZ 1979; 31: 27-31. 9. Nilsson UL. Results of low vision rehabilitation [PhD-thesis]. Link6ping: University Medical Dissertation, No. 313, 1990.
Address for correspondence: Dr Ir J.J. Neve, Visual Advice Centre, Paradijslaan 40, 5611 KP Eindhoven, The Netherlands. Phone: +31-40-455 253.
