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Biographical and clinical characteristics of a low vision population
Abstracts Study into the efficacy of a refractive multifocal intraocular lens implant A. Kotecha Mayday University Hospital, Thornton Heath, Surrey CR9 8AB. UK In the !asi decade there has been a significant advance in the types and materI& of intraocular lens implants available. Recently, there has been a trenti towards developing a multifocal intraocular lens (IOL) implant and, u ith advances in aurgtcal techniques, there is the possibility of abolishing the need for postoperative spectacle correction completely. For the last seven years at the Croydon Eye Unit we have been involved in four multiccntre clinical trials into the efficacy of the bizonal refractive form of muliifocal IOL design. The results presented focus on the IOLAB 8191M mulnfocal Implant, with a near central zone of I .5 mm diameter. and a --4.00 D addition. When implanted, this is equivalent to a spectacle additio.1 of t2.80D. The +urglcal technique used was phacoemulsification with capsularrhexls. but inc:sion size had to be increased to 6.0mm in order to insert the IOL. However. postoperative cornea1 astigmatism was still well controlled, and this retLImed to preoperative values in 82 70 patients within 5 weeks. From previor\ studies we found that patients with a preoperative cornea1 astigmatism of < I .OOD performed significantly better postoperatively (study inclusion criteria specific <2.00D of cornea1 astigmatism for patient :.]ualificatlon) To data, 245 8191M multifocals have been implanted in Europe. 228 of which have had a mlnimum of 3 months followup. At our cenire. 47 eyes have been implanted with the 819lM, 85% of whom have h;ld at least a I2 month postoperative follow-up. Our results have shown 64% patients achieving unaided visions of 6112 or better- for distance, and 84% 53 or better for near. In 45 eyes. acuity measurements with the distance correction in place indicates that 100% of eyes achieved 6112 or better for distance. and 96% 53 or better for near. The effect\ of glare, tested with the Brightness Acuity Tester (BAT), showed no significant detrimental effect on visual acuity. and this was also shown ‘o be independent of pupil size. In sulnmary. the refractive design of multifocal IOL has been shown to give su:ceahful visual results. However. in order to achieve excellent results from multifocal designs of IOL. it is essential to have an astigmaticali? neutral form of surgery and accurate biometry.
Biographical and clinical characteristics of a low vision population Katie Doorduyn and Robert Harper Department of Ophthalmology, Manchester Royal Eye Hospital. Oxford Road, Manchester Ml3 9WH, UK A retrospective survey of the optometry clinics at Manchester Royal Eye Hospitai was undertaken in order to define the biographic and clinical characteristics of the population being provided with low vision rehabilitation. For the year quarter July-September 1994. 288 patients were Identified as having attended the low vision clinic. The hospital case notes were ax,ailable for examination in 273 cases (94.8%). The results presented here relate to this latter sample of patients. Analy\is of the records revealed that the major diagnostic categories were A?MD (55.7%). glaucoma (10.6%), diabetic retinopathy (8%). other macular disorders (5.9%) and myopic degeneration (5.5%). The median dge of patients was 78 years (range 7-104) and the male : female
361
ratio was 0.87 (I.e. 53.4% female). Distance visual acuities on entry to the clinic were 6160 or better in 72.5% of the sample. A total of 141 patients (5 1.6%) were known to be registered as blind or partially sighted. A new spectacle prescription was issued to 21.6% of patients. The most frequent low vision aids (LVAs) issued were stand magnifiers (147 Illuminated and 46 non-illuminated), hand-magnifiers (67 issued) and distance monocular/binoculars (51 issued). With appropriate low vision provision. 84.5% of the sample achieved a near acuity of N8 or better. A total of 371 LVAs were issued, representing an average number of 1.36 LVAs per patient. The total cost of all LVAs issued amounted to f7818.81, giving an average cost of s28.64 per patient. This survey has provided a useful insight into the characteristics of both the population our service provides and the LVAs prescribed. Studies to measure the outcomes of our low vision provision are presently being carried out.
An evaluation of vision screening and eye examinations performed on display screen equipment users A4. McClure’. S. Barnett’ and A. J. Jackson’.2 ‘Department of Ophthalmology, Royal Victoria Hospital, Belfast BT12 6BA; and ‘Department of Ophthalmology, Queen’s University, Belfast BT7 lNN, UK The introduction of regulations governing ‘work with display screen equipment’ has placed a number of important obligations on employers. One of the most widely debated issues concerns an employee’s entitlement to ‘an appropriate eye and eyesight test’. Opinions are divided on the relative merits of the new generation of vision screening tests and their relevance wIthin the context of the regulations. In this study the results of I12 full optometric eye examinations performed on ‘regular’ display screen users. 98% of whom had previously failed the City University Computerised Vision Screening Program, are analysed. Comparisons are made between the results of eye examinations and the results of individual vision screening tests which contributed to overall test failure. Results confirm that those identified by the City University’s illiterate E visual acuity screening test as having substandard acuities often required an update to their current spectacle correction. Sixty-eight percent of those failing vision screening were spectacle wearers and of these 40% were identified as requiring an updated prescription to optimise visual potential. Results also confirm that those failmg vision screening on the basis of substandard binocular vision had either a long-standing history of oculomotor problems or an imbalance of the oculomotor system which may contribute to the presence of visual symptoms. The proportion of those complaining of ocular or visual symptoms, when assessed using the on-screen questionnaire (69%), was similar to that revealed during the recording of history and symptoms by an optometrist (65%). Interestingly, only 3% of those examined by optometrists were identified as requiring spectacles solely for display screen use. Three percent of those tested were identified as requiring medical referral, using conventional general ophthalmic services referral criteria. The authors conclude that the City University screening system. when utilised in a coordinated manner within the context of a display screen equipment work-station risk assessment programme, fulfils both staff and managerial expectations. The utilisation of (on-site) vision screening identifies those most in need of a full examination and thus allows employers to concentrate financial resources on those most likely to obtain benefit from the provision of professional services.
Biographical and clinical characteristics of a low vision population Katie Doorduyn and Robert Harper Department of Ophthalmology, Manchester Royal Eye Hospital. Oxford Road, Manchester Ml3 9WH, UK A retrospective survey of the optometry clinics at Manchester Royal Eye Hospitai was undertaken in order to define the biographic and clinical characteristics of the population being provided with low vision rehabilitation. For the year quarter July-September 1994. 288 patients were Identified as having attended the low vision clinic. The hospital case notes were ax,ailable for examination in 273 cases (94.8%). The results presented here relate to this latter sample of patients. Analy\is of the records revealed that the major diagnostic categories were A?MD (55.7%). glaucoma (10.6%), diabetic retinopathy (8%). other macular disorders (5.9%) and myopic degeneration (5.5%). The median dge of patients was 78 years (range 7-104) and the male : female
361
ratio was 0.87 (I.e. 53.4% female). Distance visual acuities on entry to the clinic were 6160 or better in 72.5% of the sample. A total of 141 patients (5 1.6%) were known to be registered as blind or partially sighted. A new spectacle prescription was issued to 21.6% of patients. The most frequent low vision aids (LVAs) issued were stand magnifiers (147 Illuminated and 46 non-illuminated), hand-magnifiers (67 issued) and distance monocular/binoculars (51 issued). With appropriate low vision provision. 84.5% of the sample achieved a near acuity of N8 or better. A total of 371 LVAs were issued, representing an average number of 1.36 LVAs per patient. The total cost of all LVAs issued amounted to f7818.81, giving an average cost of s28.64 per patient. This survey has provided a useful insight into the characteristics of both the population our service provides and the LVAs prescribed. Studies to measure the outcomes of our low vision provision are presently being carried out.
An evaluation of vision screening and eye examinations performed on display screen equipment users A4. McClure’. S. Barnett’ and A. J. Jackson’.2 ‘Department of Ophthalmology, Royal Victoria Hospital, Belfast BT12 6BA; and ‘Department of Ophthalmology, Queen’s University, Belfast BT7 lNN, UK The introduction of regulations governing ‘work with display screen equipment’ has placed a number of important obligations on employers. One of the most widely debated issues concerns an employee’s entitlement to ‘an appropriate eye and eyesight test’. Opinions are divided on the relative merits of the new generation of vision screening tests and their relevance wIthin the context of the regulations. In this study the results of I12 full optometric eye examinations performed on ‘regular’ display screen users. 98% of whom had previously failed the City University Computerised Vision Screening Program, are analysed. Comparisons are made between the results of eye examinations and the results of individual vision screening tests which contributed to overall test failure. Results confirm that those identified by the City University’s illiterate E visual acuity screening test as having substandard acuities often required an update to their current spectacle correction. Sixty-eight percent of those failing vision screening were spectacle wearers and of these 40% were identified as requiring an updated prescription to optimise visual potential. Results also confirm that those failmg vision screening on the basis of substandard binocular vision had either a long-standing history of oculomotor problems or an imbalance of the oculomotor system which may contribute to the presence of visual symptoms. The proportion of those complaining of ocular or visual symptoms, when assessed using the on-screen questionnaire (69%), was similar to that revealed during the recording of history and symptoms by an optometrist (65%). Interestingly, only 3% of those examined by optometrists were identified as requiring spectacles solely for display screen use. Three percent of those tested were identified as requiring medical referral, using conventional general ophthalmic services referral criteria. The authors conclude that the City University screening system. when utilised in a coordinated manner within the context of a display screen equipment work-station risk assessment programme, fulfils both staff and managerial expectations. The utilisation of (on-site) vision screening identifies those most in need of a full examination and thus allows employers to concentrate financial resources on those most likely to obtain benefit from the provision of professional services.