The most common LVDs demonstrated to patients were handheld magnifiers (HM) (72%, 138/192). Using HMs, 34% of clients had 1 to 2 lines of vision improvement at near, 31% have 3 to 4 lines of improvement, and 27% with >5 lines of improvement. In total, 113 (59%) were able to achieve better than N8 print, but only 58/192 (30%) purchased an HM. Of these, 90% (52/58) were of moderate magnification, 7% were low, and 3% were high magnification (Fig. 1).
Fewer (32%, 61/192) had stand magnifiers (SMs) demonstrated to them. However, the SMs demonstrated were more likely to be of high magnification compared with the HMs (43 vs. 18%, p = 0.02; Fig. 1). Of those clients who had SMs demonstrated 22% had 1 to 2 lines of vision improvement, 28% had 3 to 4 lines of improvement, and >40% had at least 5 lines of vision improvement. Despite this, only nine of the 20 clients who achieved >5 lines of vision improvement and 19 of 47 clients (40%) who achieved better than N8 vision purchased an SM at the end of the consultation. Of the total 20 clients who purchased an SM, only one (5%) was of low magnification, 11 (55%) were moderate magnification, and eight (40%) were high magnification. Of the 11 who did not purchase an SM, eight were able to achieve N8 or better vision.
The use of telescopes to improve distance vision was occasionally recommended in the clinic. Only 12 of the 192 participants trialed a telescope. Of these, four achieved vision better than 6/12, another four were able to see <6/12 to 6/18, three improved vision to <6/18 to 6/60, and one achieved vision <6/60. Six of these (50%) had >5 lines of vision improvement, four (33%) achieved 3 to 4 lines of improvement, and two (17%) obtained 1 to 2 lines of improvement. However, only two telescopes were purchased and these were acquired by participants who could achieve vision better than 6/12 (logMAR <0.3) with the aid of the telescopes.
Around-the-neck embroidery magnifiers of 2× magnifications were recommended to 14 participants but were purchased by only five of them. Spectacle-mounted magnifiers (clip-on plus lenses) were demonstrated to five clients and none chose to purchase them. Similarly, CCTV was demonstrated to 11 participants, but none expressed interest in the acquisition of the device. The likelihood of an individual recommended or acquiring LVDs (including HM, SM, around-the-neck embroidery magnifiers, spectacle mounted magnifiers, telescopes, and CCTV) was not statistically significantly different by age, gender, distance or near vision, cause of vision loss, or goal of rehabilitation (p > 0.05).
Following assessments by low vision advisors and optometrists, 80 of the 192 (42%) clients were recommended for orthoptics review regarding training in the use of optical and non-optical aids, lighting advice, visual field testing, and eccentric viewing training. Those younger than 70 years were less likely to require an orthoptic review than clients of any other age groups (p = 0.04). Nonetheless, 70 of 80 (88%) accepted the recommended referral. There was no significant difference in age, gender, distance or near vision, cause of VI, and rehabilitation goals between those who accepted orthoptic services and those who did not.
In contrast, with increasing age, clients were less likely to be referred to see an O&M instructor (p = 0.002). Of the 31 clients who were recommended to see an O&M instructor, 68% accepted the offer. Those who declined this service were more likely to be male (p = 0.004). However, this difference disappeared when adjusted for age.
The low vision advisors suggested OT assessments to 46 (24%) participants. Of these, 39 (85%) accepted the offer. There were no significant differences in age, gender, main cause of vision loss, distance and near vision, and goal of rehabilitation for those who were referred and those who had declined OT involvement.
In total, 61 participants (32%) were considered by the low vision advisors as requiring tertiary services such as either O&M or OT. However, only 46 (24%) participants accepted any of these tertiary rehabilitation services (Table 2). Of the 146 participants (76%) who did not attend any tertiary auxiliary services, only 6 required prescription of either high magnification HM (1/6) or SM (5/6). In other words, the remaining 73% (140/192) could have their needs adequately met by a secondary level LVC as defined by WHO.
This retrospective study of the services provided in an Australian LVC gives important insights into the current pattern of practice, the needs and the equipment of choice for those with low vision. Around the world, many countries (including Australia) have set up tertiary level LVCs to provide low vision rehabilitation. However, in many cases, a secondary level LVC is all that is required. Through this study, we are able to provide supporting data to estimate the proportion of people with low vision that can be adequately managed by a secondary level LVC.
Secondary level LVCs have been proposed by Vision 202012 to be an integral part of existing eye care services. As set out by WHO, the establishment of such services will require basic ophthalmic equipment such as a retinoscope, direct ophthalmoscope, trial lenses and frame, distance and near logMAR and contrast sensitivity charts and a small range of spectacle, handheld, stand, dome or bar magnifiers, monocular telescopes, and ultraviolet protection with luminous/selective transmission filters. Equipment such as color vision tests, hand disc perimetry, amsler grid, tangent screen, high magnification LVDs, and electronic magnifiers are not necessarily required. The estimated cost to equip an LVC at secondary level is U.S. $4000.13 In this study, the mismatch between the range of low vision service options available at a tertiary rehabilitation centers and choices in uptake of low vision services demonstrates that the needs of many could be met at a secondary level clinic.
Spectacles magnifiers and HMs were the most common types of low vision aids prescribed in this tertiary LVC and were usually of low to moderate magnification (92%). This high percentage of patients adequately managed by LVDs of up to ×5 magnification is consistent with findings in other studies. Leat and Rumney18 showed that 71.6% of patients were supplied with magnification of ≤ ×4 and around 80% were of ×5 or less magnification. Similarly, Wolffsohn and Cochrane19 found that the median magnification of LVDs prescribed was ×3.5 and the need of majority of the visually impaired population can be adequately met by stocking LVDs of up to ×7.
Of the 192 clients examined, 50 (24%) had additional assessment and training by an O&M instructor or OT to enhance their rehabilitation process. Including the six other clients requiring high magnification LVDS, in total, only 56 of the 192 (27%) participants used services at a tertiary level. In another words, it suggests that fewer than 30% of people with low vision require referrals to tertiary centers if secondary level LVCs are available. This is the first evidence-based result that we are aware of, against the WHO estimation/hypothesis that 50% of low vision population can be adequately managed by secondary level LVC. Future studies in nations with different low vision practices will be useful to compare with our results and to determine whether the results can be extended to other countries or communities.
If our study findings are representative of the demand in the wider community, a secondary level LVC would have the capacity to provide the majority of magnifiers and training that are helpful to people with VI. These magnifiers could be prescribed through an integrated service in preexisting eye care facilities. On-site basic training in magnifier use and low vision strategies could then be provided to the clients without further appointments. This would greatly facilitate access to low vision services by eliminating barriers such as transportation, distance, and lack of information.6,20
Secondary level LVCs can play an important role in bridging the gap between primary low vision care by community-based optometrists and the specialist tertiary low vision rehabilitation centers. Other than secondary level LVCs, other models of care have also been proposed to meet the challenge of providing easily accessible low vision services to an ageing population, especially in countries or areas where limited resources are available. One such model includes the outreach clinics in Northern Ireland.21 This involved a team of optometrists and rehabilitation workers attending communities requiring low vision care. However, this model of care required setting up a team of highly trained personnel and came at a cost to the already stretched healthcare resources. Another proposed model of care was an “open” LVC, such as that in Wales,18 where anyone can attend the clinic including those who self-referred. However, under this model of care, in addition to the problem of “inappropriate” referrals, patients will still require a second appointment and the need to travel again. When LVCs are established in conjunction with, and integrated into, ophthalmology clinics, departments, or hospitals, it can provide immediate and accessible low vision services, overcome barriers to service provision and allow rational allocation of valuable resources. It will also improve the flow of patients to tertiary vision rehabilitation.
Interestingly, in this study, some magnifiers were rarely demonstrated or recommended to clients. These included spectacle-mounted magnifiers—which offer magnification while allowing users to be hands-free; CCTV—which provide high magnification while maintaining a good working distance; and telescopes—which improve distance vision. There may be a multitude of reasons for this. It may be a reflection of the culture of common low vision practice, limitations of time, the needs and requirements of clients, costs of LVDs (because of lack of government funding), and ergonomics of LVDs. The reasons are beyond the scope of this article and further studies will be needed to ascertain the underlying reasons why such useful tools are often omitted in initial low vision assessments in our study clinic. However, this possible bias against the use of CCTV, telescopes, or spectacle-mounted spectacles may lead to an over-estimation of the proportion of LV population that are suitable for secondary level care.
A similar pattern of LVD use was also found in a separate study of the same center before 2 years19 and also other LVCs in United Kingdom.21–23 Despite having a higher percentage of SMs prescribed in these studies (ranging from 30 to 65%), possibly because of their recruitment of all attending patients rather than new patients only, they also have low propensities toward the use of spectacle-mounted magnifiers, telescopes, or CCTV. In India, where there were sparse low vision service deliveries, these LVDs were never prescribed.24 As pointed out by Crossland and Silver,23 spectacle-mounted telescopes and CCTV were less frequently prescribed, possibly because of financial burden and availability.
In comparison, the university-based LVC in Wales18,25 and the American-based LVC26 tend to have a larger percentage of spectacle-mounted magnifiers, telescopes, or CCTV prescribed. Leat and Rumney18 found that around 20% of patients older than 55 years were prescribed with spectacle-mounted magnifiers and 25% younger than 55 years with telescopes, whereas Scott et al.26 showed that as high as 59% of patients were supplied with spectacle-mounted magnifiers, 8.3% with handheld telescope, and 3.8% with electronic devices. There is an enormous variation in the types of LVDs prescribed at different LVCs around the world.
Because of different LV rehabilitation practices, we acknowledge that the result of our study may not be applicable or extendable to all low vision services. There may be different staffing structures, various levels of training and capabilities of ophthalmic personnel, diverse cultures of practice, unique assessment protocols, and different patterns or triggers for auxiliary referrals. All these factors may alter the proportion of the LV population that can be adequately managed at a secondary level.
In addition, there are a number of other limitations in this study. There is the potential bias in the results extrapolated from data relating to clients presenting to a tertiary level LVC. In particular, these clients may have had poor vision for a long period of time and had finally accepted the need for assistance. Thus, they may have required a higher level of care, including more frequent use of higher magnification LVDs and were more likely to avail themselves of auxiliary services such as OT and O&M than the total low vision population. However, given there were no secondary level LVCs present in Melbourne at the time of data collection, the demographics of the study subjects are likely to represent the spectrum of people with low vision, thus minimizing the selection bias present here. As the study only includes first time users of the LVC, there may be a propensity toward clients with milder visual impairment, leading to use of low-powered LVDs, less intensive rehabilitation or needs, and perhaps refusal of services because of denial or lack of acceptance.
Low vision rehabilitation is an important process in improving quality of life. The use of secondary level integrated low vision services would mean that people could potentially receive interventions at an earlier stage.14,15 Early interventions and improvement in quality of life may also reduce the need for intense rehabilitation in the future, thereby further alleviating the burden on tertiary level low vision care. These predictions of the capabilities of secondary level LVCs will need to be confirmed by evaluation of such services, such as those currently being established at Royal Victorian Eye and Ear Hospital.
The establishment of secondary level LVCs as part of existing eye care facilities would improve access to low vision care and resources and could meet the needs of up to 70% of people with low vision. By doing so, these secondary level LVCs could do much to reduce the impact of VI and improve vision-related quality of life in both developing and developed countries.
We thank Jennifer Hassell and the staff of Vision Australia for their assistance in the collection of data.
Elaine Y. H. Wong
Centre for Eye Research Australia
University of Melbourne
32 Gisborne Street
East Melbourne, VIC 3002
1. Resnikoff S, Pascolini D, Etya'ale D, Kocur I, Pararajasegaram R, Pokharel GP, Mariotti SP. Global data on visual impairment in the year 2002. Bull World Health Organ 2004;82:844–51.
2. Frick KD, Foster A. The magnitude and cost of global blindness: an increasing problem that can be alleviated. Am J Ophthalmol 2003;135:471–6.
3. Taylor HR, Pezzullo ML, Keeffe JE. The economic impact and cost of visual impairment in Australia. Br J Ophthalmol 2006;90:272–5.
4. World Health Organization. Asia Pacific Regional Low Vision Workshop, Hong Kong 28–30 May 2001:WHO/PBL/02.87. Geneva: World Health Organization; 2002.
5. World Health Organization. Preventing Blindness in Children:WHO/PBL/00.77: Report of a WHO/IAPB meeting, Hyderabad, India, 13–17 April 1999. Geneva: World Health Organization; 2000.
6. O'Connor PM, Mu LC, Keeffe JE. Access and utilization of a new low-vision rehabilitation service. Clin Experiment Ophthalmol 2008;36:547–52.
7. Gold D, Zuvela B, Hodge WG. Perspectives on low vision service in Canada: a pilot study. Can J Ophthalmol 2006;41:348–54.
8. Pollard TL, Simpson JA, Lamoureux EL, Keeffe JE. Barriers to accessing low vision services. Ophthalmic Physiol Opt 2003;23:321–7.
9. Lovie-Kitchin JE, Keeffe JE, Taylor HR. Referral to low vision services by optometrists. Clin Exp Optom 1996;79:227–34.
10. Culham LE, Chabra A, Rubin GS. Clinical performance of electronic, head-mounted, low-vision devices. Ophthalmic Physiol Opt 2004;24:281–90.
11. Keeffe JE, Lovie-Kitchin JE, Taylor HR. Referral to low vision services by ophthalmologists. Aust N Z J Ophthalmol 1996;24:207–14.
12. Minto H, Awan H. Establishing low vision services at secondary level. Community Eye Health 2004;17:5.
13. Standard List for Low Vision Services: VISION 2020 Low Vision Group. Community Eye Health 2004;17:8.
15. Chang PP-C. The global mapping of low vision services. PhD Thesis. University of Melbourne; 2009.
16. Lamoureux EL, Pallant JF, Pesudovs K, Rees G, Hassell JB, Keeffe JE. The effectiveness of low-vision rehabilitation on participation in daily living and quality of life. Invest Ophthalmol Vis Sci 2007;48:1476–82.
17. Bailey IL, Lovie JE. The design and use of a new near-vision chart. Am J Optom Physiol Opt 1980;57:378–87.
18. Leat SJ, Rumney NJ. The experience of a university-based low vision clinic. Ophthalmic Physiol Opt 1990;10:8–15.
19. Wolffsohn JS, Cochrane AL. The changing face of the visually impaired: the Kooyong low vision clinic's past, present, and future. Optom Vis Sci 1999;76:747–54.
20. Owsley C, McGwin G, Scilley K, Girkin CA, Phillips JM, Searcey K. Perceived barriers to care and attitudes about vision and eye care: focus groups with older African Americans and eye care providers. Invest Ophthalmol Vis Sci 2006;47:2797–802.
21. Lindsay J, Bickerstaff D, McGlade A, Toner A, Jackson AJ. Low vision service delivery: an audit of newly developed outreach clinics in Northern Ireland. Ophthalmic Physiol Opt 2004;24:360–8.
22. Margrain TH. Helping blind and partially sighted people to read: the effectiveness of low vision aids. Br J Ophthalmol 2000;84:919–21.
23. Crossland MD, Silver JH. Thirty years in an urban low vision clinic: changes in prescribing habits of low vision practitioners. Optom Vis Sci 2005;82:617–22.
24. Khan SA, Das T, Kumar SM, Nutheti R. Low vision rehabilitation in patients with age-related macular degeneration at a tertiary eye care centre in southern India. Clin Experiment Ophthalmol 2002;30:404–10.
25. Leat SJ, Fryer A, Rumney NJ. Outcome of low vision aid provision: the effectiveness of a low vision clinic. Optom Vis Sci 1994;71:199–206.
26. Scott IU, Smiddy WE, Schiffman J, Feuer WJ, Pappas CJ. Quality of life of low-vision patients and the impact of low-vision services. Am J Ophthalmol 1999;128:54–62.
Keywords:© 2011 American Academy of Optometry
low vision clinic; vision rehabilitation; vision impairment; low vision