Engaging families in health services research on childhood visual impairment: barriers to, and degree and nature of bias in, participation
AIM: To investigate the barriers to, and degree and nature of bias in, participation in health services research by parents of children with visual impairment.
METHODS: Parents of children newly diagnosed with ophthalmic disorders at Great Ormond Street Hospital, London, participated in a study to elicit their health service experiences and needs through a postal questionnaire survey followed by in-depth interviews. The participating and non-participating families were compared at different stages of recruitment, according to sociodemographic and clinical characteristics.
RESULTS: 20% (55) of all eligible families could not be invited to participate because of out of date contact details for either the family and/or family doctor in the hospital and/or community record systems. Completed questionnaires were received from 67% (147/221) of contacted families, although only 6% actively declined to take part. Compared to non-participating parents, those who took part were more likely to be white British, from higher socioeconomic groups, have English as their main language, and have no other visually impaired family members. There were no significant differences according to the clinical characteristics of their affected children.
CONCLUSIONS: Families from socioeconomically deprived and ethnic minority groups are likely to be less visible than others in health services research on childhood visual impairment. Geographical mobility in families of young children with visual disability poses a potentially important obstacle to engaging them in research on their experiences of health services. These findings indicate the importance of addressing potential biases in the design and interpretation of future studies, to ensure equity in recommendations for policy and practice, and in implementation of services.
Reprinted courtesy of: Br J Ophthalmol. 2004 Jun; 88(6): 782-787.
Evaluation of screening procedures for congenital cataracts
G Magnusson, G P Jakobsson, U Kugelberg, A Lundvall, E Maly, K Tornqvist, M Abrahamsson, B Andreasson, MP Borres, U Broberger, L Hellstrom-Westas, R Kornfalt, N Nelson, J Sjostrand, K Thiringer
AIM: To evaluate the efficacy of two different Swedish screening procedures for early detection of congenital cataracts in comparison with no screening.
METHODS: Children born between January 1992 and December 1998 in Swedish regions with an established eye-screening routine procedure, diagnosed with congenital cataract, and operated on before 1 year of age, were included in a retrospective study. Age at referral and age at time of the operation were compared between regions using different screening procedures: screening in the maternity wards (Region 1), at the well-baby clinics (Region 2) and one region without any screening (Region 3).
RESULTS: Seventy-two children were included in the study. Concerning early diagnosis and surgery, Region 1 differed significantly from Regions 2 and 3, which were more similar and were combined for further analysis. The difference in detected cases was greatest at 21 days of age (55% vs 18%; p < 0.001), but persisted even at 100 days of age (78% vs 64%; p < 0.2). Region 1 screening resulted in more and earlier cases detected than the other two regions (22 vs 15 per 100,000 births). In 72% of all cases, surgery was performed in response to referrals from either the maternity wards (36%), or the well-baby clinics (36%). However, half of the cases from the well-baby clinics were detected too late, i.e. at > 100 days.
CONCLUSION: Eye screening in the maternity ward is preferable to well-baby clinic screening and to no screening at all, since it leads to early detection. Screening should also be performed routinely at well-baby clinics within the period when successful treatment is possible.
Reprinted courtesy of: Acta Paediatr. 2003 Dec; 92(12): 1468-1473.
Outcome of lens aspiration and intraocular lens implantation in children aged 5 years and under
L Cassidy, J Rahi, K Nischal, I Russell-Eggitt, D Taylor
AIMS: To determine the visual outcome and complications of lens aspiration with intraocular lens implantation in children aged 5 years and under.
METHODS: The hospital notes of all children aged 5 years and under, who had undergone lens aspiration with intraocular lens implantation between January 1994 and September 1998, and for whom follow up data of at least 1 year were available, were reviewed.
RESULTS: Of 50 children who underwent surgery, 45 were eligible based on the follow up criteria. 34 children had bilateral cataracts and, of these, 30 had surgery on both eyes. Cataract was unilateral in 11 cases; thus, 75 eyes of 45 children had surgery. Cataracts were congenital in 28 cases, juvenile in 16, and traumatic in one case. The median age at surgery was 39 months (range 11-70 months). Follow up ranged from 12-64 months (median 36 months). Of 34 children with bilateral disease, 25 (73.5%) had a final best corrected visual acuity of 6/12 or better, while seven (20.5%) achieved 6/18 or less; in one child the vision improved from UCUSUM to CSM but another, who had only one eye operated on, was unable to fix or follow with this eye preoperatively or 2 years postoperatively. Of 11 children with unilateral cataract, five (45.5%) had a final best corrected visual of 6/12 or better, and six (54.5%) 6/18 or less. A mild fibrinous uveitis occurred in 20 (28.2%) eyes in the immediate postoperative period, but resolved with topical steroids. One child had a vitreous wick postoperatively requiring surgical division. Glaucoma, endophthalmitis, or retinal detachment have not been observed so far in any patient postoperatively.
CONCLUSION: From this series the authors suggest that, in children aged 5 years and under, lens aspiration with intraocular lens implantation is a safe procedure, with a good visual outcome in the short term. Further studies are needed to investigate these outcomes in the long term.
Reprinted courtesy of: Br J Ophthalmol. 2001 May; 85(5):540- 542.
Is early surgery for congenital cataract a risk factor for glaucoma?
M Vishwanath, R Cheong-Leen, D Taylor, I Russell-Eggitt, J Rahi
AIMS: To estimate the risk of aphakic glaucoma after lensectomy for congenital cataract and its association with surgery within the first month of life.
METHOD: A retrospective case notes review was conducted of all patients who had lensectomy for congenital cataract during their first year of life at Great Ormond Street Hospital between 1994 and 1997. Patients with pre-existing glaucoma, anterior segment dysgenesis, and Lowe syndrome were excluded. The risk of aphakic glaucoma after surgery was estimated using Kaplan-Meier survival analysis.
RESULTS: 80 patients, undergoing 128 lensectomies were eligible. Of these, six patients (nine eyes) were lost to follow up. Based on eye count, the risk of glaucoma by 5 years after lensectomy was 15.6% (95% CI 10.2 to 23.4). Based on patient count, the 5 year risk of glaucoma in at least one eye following bilateral surgery was 25.1% (95% CI 15.1 to 40.0). The incidence of glaucoma remained at a constant level for the first 5 years after surgery. After early bilateral lensectomy, within the first month of life, the 5 year risk of glaucoma in at least one eye was 50% (95% CI 27.8 to 77.1) compared to 14.9% (95% CI 6.5 to 32.1) with surgery performed later (log rank test, p = 0.012). There was no significant difference (Kolmogorov-Smirnov test: unilateral lensectomy p = 0.587, bilateral lensectomy p = 0.369) in 5 year visual outcomes between eyes operated before and after 1 month of age.
CONCLUSION: Bilateral lensectomy during the first month of life is associated with a higher risk of subsequent glaucoma than with surgery performed later. The reason for this is unclear but it may be prudent, in bilateral cases, to consider delaying surgery until the infant is 4 weeks old. As the incidence of glaucoma is similar for each year after surgery, long term glaucoma surveillance is mandatory.
Reprinted courtesy of:Br J Ophthalmol. 2004 Jul; 88(7):905-910.