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At least 1,423 records · Page 79Linked to original sources
PubMed2002

Effect of hyperopic laser in situ keratomileusis on ocular alignment and stereopsis in patients with accommodative esotropia.

OBJECTIVE: To evaluate the effect of laser in situ keratomileusis (LASIK) on ocular alignment and stereopsis in patients with accommodative esotropia. DESIGN: Retrospective, non-comparative, interventional case series. PARTICIPANTS: Since 1998, 27 patients (mean age, 33.3 years; range, 10-52 years) with comitant esophoria or esotropia and hyperopia meeting eligibility requirements underwent bilateral LASIK for correction of refractive error. INTERVENTION: Bilateral hyperopic LASIK was performed using the Technolas Keracor 217 excimer laser (Bausch & Lomb) in 22 patients and using the Nidek 5000 excimer laser in 5 patients. MAIN OUTCOME MEASURES: Visual acuity (best-corrected and uncorrected), refractive error, ocular alignment, and stereopsis were recorded before and after LASIK. Log transformation of each visual acuity was done before data analysis. RESULTS: Using paired t tests, the mean uncorrected esotropia was significantly reduced from 9.0 prism diopters (PD) (range, 0 [esophoria only] to 20 PD; standard deviation [SD], 7.39) before surgery to 3.3 PD (range, 0-15 PD; SD, 6.20) after surgery (P < 0.0001). Most patients (14 patients, 58%) had a reduction in esodeviation after LASIK, but 10 patients (42%) had no response to surgery, and these patients could not be predicted on the basis of preoperative sensorimotor testing. No patient had a worsening sensorimotor status after LASIK. Nine patients subsequently underwent conventional eye muscle surgery. CONCLUSIONS: Hyperopic LASIK was effective in reducing the mean uncorrected esotropia in this group of patients. However, accurately determining those patients most likely to benefit from the procedure was difficult.

Accommodation, Ocular↗
PubMed1985

Prevalence of myopia in school children in Vanuatu.

The onset of myopia typically occurs in childhood and increases during puberty. We studied the vision and refractive errors of 977 school children (ages 6 to 17 years) in 1983. Myopia in the group was extremely low; 97% had vision of 6/6, and 1.3% had myopia greater than 0.25D. Regression analysis revealed a change in mean refraction of -0.016D/year for males and -0.024D/year for females. There were no significant differences between males and females. These children engaged in about 8 hours of school work per day, and we conclude that genetic factors predominate over environmental factors in the determination of myopic refractive errors for this group.

Adolescent↗
PubMed2003

Five-year incidence of bilateral cause-specific visual impairment in the Melbourne Visual Impairment Project.

PURPOSE: To describe the age-, gender-, and cause-specific 5-year incidence of bilateral visual impairment in participants in the Melbourne Visual Impairment Project, Victoria, Australia. METHODS: Participants aged 40 years and older were recruited from Melbourne, Victoria, Australia, by random cluster sampling. The mean age of the 3271 (83% of the eligible) participants was 59 +/- 12 (SD) years. Of the participants, 54% were female. The initial baseline study (1992-1994) was followed by a 5-year incidence study (1997-1999). At both time points of the study, participants underwent a standardized testing procedure. Distance and near vision was tested using logarithm of the minimum angle of resolution (logMAR) charts, followed by refraction if needed. Visual fields were assessed by the 24-2 Humphrey field test (FastPac, Humphrey Field Analyzer; Carl Zeiss Meditec, Dublin, CA). Also, intraocular pressure, ocular motility, dilated ophthalmoscopy, and photography of the lens and the fundus were conducted. Furthermore, an interview included demographic characteristics, history of eye disease, medical history, and medication use. For classification of visual impairment, both visual acuity (VA) and visual fields (VF) examination results were used. Four levels of bilateral presenting visual impairment were defined: mild (VA, <20/40-20/60, and/or VF, homonymous hemianopia), moderate (VA, <20/60-20/200, and/or VF, constriction <20 degrees to 10 degrees from fixation), severe (VA, <20/200-10/200, and/or VF, constriction <10 degrees to 5 degrees from fixation), and profound (VA, <10/200, and/or VF, constriction <5 degrees from fixation). For all participants found to be visually impaired, the major cause was identified. RESULTS: Of the 3040 people eligible to attend follow-up 2594 (85%) participated. Data were available for 2530 (98%) participants. In 105 participants (4.22%; 95% confidence limit 2.58-5.85) some degree of visual impairment developed. The main causes were undercorrected refractive error (59%), age-related macular degeneration, cataract and neuro-ophthalmic disorders (7% each), glaucoma (3%), and diabetic retinopathy (1%). The main cause of severe and profound visual impairment was age-related macular degeneration (37%). CONCLUSIONS: Undercorrected refractive error was the primary cause of new cases of visual impairment in this population. Further research is needed to understand the origin of this and to develop appropriate prevention measures. Age-related macular degeneration is the primary cause of severe or profound vision loss in Australia. This disease requires further investigation for effective cure and preventive strategies.

Adult↗
PubMed2006

Accommodative lag before and after the onset of myopia.

PURPOSE: To evaluate accommodative lag before, during the year of, and after the onset of myopia in children who became myopic, compared with emmetropes. METHODS: The subjects were 568 children who became myopic (at least -0.75 D in each meridian) and 539 children who were emmetropic (between -0.25 D and +1.00 D in each meridian at all visits) participating between 1995 and 2003 in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study. Accommodative lag was measured annually with either a Canon R-1 (Canon USA., Lake Success, NY; no longer manufactured) or a Grand Seiko WR 5100-K (Grand Seiko Co., Hiroshima, Japan) autorefractor. Subjects wore their habitual refractive corrections while viewing a letter target accommodative stimulus of 4 D (either in a Badal system or at 25 cm from the subject, designated Badal and near, respectively) or of 2 D (Badal only). Refractive error was measured with the same autorefractor in subjects under cycloplegia. Accommodative lag in children who became myopic was compared to age-, gender-, and ethnicity-matched model estimates of emmetropic values for each annual visit from 5 years before, through 5 years after, the onset of myopia. RESULTS: In the sample as a whole, accommodative lag was not significantly different in children who became myopic compared with model estimates in emmetropes in any year before onset of myopia for either the 4-D or 2-D Badal stimulus. For the 4-D near target, there was only a greater amount of accommodative lag in children who became myopic compared with emmetropes 4 years before onset (difference, 0.22 D; P = 0.0002). Accommodative lag was not significantly elevated during the year of onset of myopia in any of the three measurement conditions (P < 0.82 for all three). A consistently higher lag was seen in children after the onset of their myopia (range, 0.13-0.56 D; P < 0.004 for all comparisons). These patterns were generally followed by each ethnic group, with Asian children typically showing the most, African-American and white children showing the least, and Hispanic children having intermediate accommodative lag. CONCLUSIONS: Substantive and consistent elevations in accommodative lag relative to model estimates of lag in emmetropes did not occur in children who became myopic before the onset of myopia or during the year of onset. Increased accommodative lag occurred in children after the onset of myopia. Elevated accommodative lag is unlikely to be a useful predictive factor for the onset of myopia. Increased hyperopic defocus from accommodative lag may be a consequence rather than a cause of myopia.

Accommodation, Ocular↗
PubMedDate not supplied

Unilateral refractive keratotomy for anisometropia.

BACKGROUND: In anisometropia, the asymmetry of refractive error produces disparity of image magnification (aniseikonia) that can create visual discomfort, especially when asymmetry is 3.00 diopters or more. METHODS: A prospective study of 20 eyes of 20 patients between 18 and 61 years of age who underwent unilateral radial and/or transverse keratotomy was conducted; results of at least 12 months follow-up are presented. The efficacy of keratotomy was evaluated by the following criteria: 1) change in spherical and cylindrical refraction, 2) decrease in refraction difference between two eyes of each patient, 3) change in spectacle-corrected visual acuity, and 4) change in binocular vision functions and asthenopic complaints. RESULTS: Mean decrease in spherical refractive error was 3.66 +/- 1.58 D (range, 1.25 to 7.50 D) and 2.08 +/- 0.81 D (range, 1.00 to 3.50 D) in astigmatic refraction. The mean refraction difference between two eyes was 4.90 +/- 2.20 D preoperatively, and this difference regressed to 1.79 +/- 1.42 D postoperatively. Spectacle-corrected visual acuity increased in seven eyes (35%), remained the same in 12 eyes (60%) and decreased in one eye (5%). All patients reported relief of asthenopic complaints. Fusion amplitudes increased in 12 (60%) patients. Stereoscopic vision improved in five (25%) patients. CONCLUSION: Monocular refractive keratotomy can significantly decrease anisometropia.

Adolescent↗
PubMedDate not supplied

Randomized comparison of diode laser photocoagulation versus cryotherapy for threshold retinopathy of prematurity: 3-year outcome.

PURPOSE: To report the structural and functional outcomes at a minimum of 3 years postmenstrual corrected age following laser- or cryoablation of threshold retinopathy of prematurity (ROP). METHODS: Nineteen patients were entered into a prospective, randomized treatment protocol, in which one eye received cryotherapy and the other received diode laser photocoagulation. Asymmetric eyes were randomly assigned. Two patients have died and five were not available for 3-year outcome exams. RESULTS: Seven males and five females with a mean birthweight of 638 g and a mean gestational age of 24.9 weeks were examined. Two patients had asymmetrical disease and received laser photocoagulation. Two discordant structural outcomes were present among the 10 symmetrical cases. The laser-treated eyes had the favorable outcome; the cryotherapy-treated eyes had the unfavorable outcome. The geometric mean visual acuity after laser photocoagulation was 20/52; after cryotherapy, it was 20/91 (P = 0.046). The mean refractive error was -6.60 diopters (D) after laser photocoagulation and -7.62 D after cryotherapy. Seven patients (58%) have developed strabismus. CONCLUSIONS: Laser photocoagulation appears to have an outcome at least comparable to cryotherapy when the patients are examined 3 years following therapy. These data, including visual acuity and refractive error, suggest that laser photocoagulation may have a minimal advantage over cryotherapy in the treatment of ROP.

Child, Preschool↗
PubMed2002

Distant visual acuity in chronic psychiatric patients. A pilot study.

BACKGROUND: There is a paucity of systematically collected data on visual impairment in patients with chronic psychiatric disorders. The aim of this pilot study was to estimate the magnitude of impairment of distant visual acuity (DVA) including refractive and non-refractive errors in institutionalized psychiatric patients awaiting resettlement in the community in Hong Kong. METHOD: DVA was tested using the Snellen method in a randomly selected cohort of 428 institutionalized psychiatric patients from the four long-stay rehabilitation units in Hong Kong. The pinhole method was employed to differentiate between refractive and non-refractive impairment of DVA. RESULTS: Seventy-five percent of the sample had impaired DVA; 39 % of the subjects had refractive error (myopia). Only a small percentage of patients wore spectacles and had adequately corrected vision. Patients with impaired DVA were significantly older than those with normal DVA. CONCLUSION: While the frequency of myopia corresponds to that found in the general population in Hong Kong, the nature of non-refractive impairment needs further investigation including systematic eye examination, and examination of medication and life-style factors. Periodical eye examinations should be part of comprehensive health assessment for chronic psychiatric patients.

Chronic Disease↗
PubMed1996

Optic disc morphology in "age-related atrophic glaucoma".

BACKGROUND: This study was performed in order to evaluate whether, in primary open-angle glaucoma (POAG), patients with a different degree of fundus tessellation vary in optic disc morphology and level of intraocular pressure. METHODS: Color stereo optic disc photographs of 562 patients with POAG and a myopic refractive error of less than -8 diopters were morphometrically examined. According to the degree of fundus tessellation, the total group was divided into a tessellated subgroup (n = 256) and a nontessellated subgroup (n = 306), both matched for neuroretinal rim area and refractive error. RESULTS: In the tessellated subgroup, as compared to the nontessellated subgroup, the mean maximal intraocular pressure values were significantly lower, the parapapillary atrophy was significantly larger, the optic cup was significantly more shallow, frequency of disc hemorrhages was lower, the mean visual field defect was significantly more marked, and patient age was significantly higher. Within the whole study group, the degree of fundus tessellation increased significantly (P < 0.005) with decreasing mean maximal intraocular pressure, decreasing optic cup depth, and increasing degree of parapapillary atrophy. In the subgroups with the highest degree of fundus tessellation, parapapillary atrophy was the greatest and the mean maximal intraocular pressure was the lowest compared to other subgroups. CONCLUSION: At the low-pressure end of POAG, marked fundus tessellation is associated with large parapapillary atrophy, shallow disc cupping, mostly concentric emaciation of the neuroretinal rim, and high patient age. The results suggest a distinct subtype of POAG in older patients with relatively low intraocular pressure leading to a mainly diffuse atrophy of the optic nerve.

Female↗
PubMed1996

Ophthalmic manifestations of Smith-Magenis syndrome.

PURPOSE: The Smith-Magenis syndrome (SMS) is a multiple-anomaly, mental retardation syndrome associated with deletions of a contiguous region of chromosome 17p11.2. Prior reports have described ophthalmic anomalies with SMS, including telecanthus, ptosis, strabismus, myopia, iris anomalies, cataracts, optic nerve hypoplasia, and retinal detachment. This report defines the ophthalmic spectrum in 28 individuals with SMS subjected to a multidisciplinary clinical and molecular survey. METHODS: Individuals with deletion of chromosome 17p11.2 detected by high-resolution cytogenetic analysis underwent complete ophthalmologic evaluation comprised of ophthalmic history, visual acuity, cycloplegic refraction, motility, and biomicroscopic and ophthalmoscopic examination. RESULTS: Among the 28 subjects, ranging in age from 0.8 to 29.3 years, the most frequent ocular findings were iris anomalies (68%), microcornea (50%), myopia (42%), and strabismus (32%). Bilateral microphthalmos with uveal and retinal coloboma was observed in one individual. No subject had cataract or retinal detachment. CONCLUSIONS: This is the largest single-center series of subjects with SMS that includes ophthalmic evaluation. As in prior reports, iris anomalies and strabismus were observed, but microcornea had not been noted previously. The absolute refractive error was hypermetropic in half of these subjects. Cataract, ptosis, and retinal pathology, including detachment, were not observed in any subject. All individuals with SMS should be evaluated by an ophthalmologist, with special attention to strabismus, microcornea, iris anomalies, and refractive errors.

Abnormalities, Multiple↗
PubMed2004

A susceptibility locus for myopia in the normal population is linked to the PAX6 gene region on chromosome 11: a genomewide scan of dizygotic twins.

Myopia is a common, complex trait with considerable economic and social impact and, in highly affected individuals, ocular morbidity. We performed a classic twin study of 506 unselected twin pairs and inferred the heritability of refractive error to be 0.89 (95% confidence interval 0.86-0.91). A genomewide scan of 221 dizygotic twin pairs, analyzed by use of optimal Haseman-Elston regression methods implemented by use of generalized linear modeling, showed significant linkage (LOD >3.2) to refractive error at four loci, with a maximum LOD score of 6.1 at 40 cM on chromome 11p13. Evidence of linkage at this locus, as well as at the other linkage peaks at chromosomes 3q26 (LOD 3.7), 8p23 (LOD 4.1), and 4q12 (LOD 3.3), remained the same or became stronger after model fit was checked and outliers were downweighted. Examination of potential candidate genes showed the PAX6 gene directly below the highest peak at the 11p13 locus. PAX6 is fundamental to identity and growth of the eye, but reported mutations usually result in catastrophic congenital phenotypes such as aniridia. Haplotype tagging of 17 single-nucleotide polymorphisms (SNPs), which covered the PAX6 gene and had common minor allele frequencies, identified 5 SNPs that explained 0.999 of the haplotype diversity. Linkage and association analysis of the tagging SNPs showed strong evidence of linkage for all markers with a minimum chi 21 of 7.5 (P=.006) but no association. This suggests that PAX6 may play a role in myopia development, possibly because of genetic variation in an upstream promoter or regulator, although no definite association between PAX6 common variants and myopia was demonstrated in this study.

Aged↗
PubMed2002

Height and its relationship to refraction and biometry parameters in Singapore Chinese children.

PURPOSE: To examine the association between the anthropometric measurements of height, weight, body mass index (BMI) and refraction and other ocular parameters in Singapore Chinese children. METHODS: In a cross-sectional study of 1449 Chinese schoolchildren, aged 7 to 9 years, from three Singapore schools, height and weight were measured according to standard protocol, and BMI was calculated. Refractive error and corneal curvature measures were determined by autorefraction in eyes under cycloplegia. Axial length, vitreous chamber depth, lens thickness, and anterior chamber depth were measured using A-scan biometry ultrasonography. RESULTS: In comparison with the children with height in the first quartile for a given age and gender, the eyeball length in children in the fourth quartile was 0.46 mm longer, the vitreous chamber depth 0.46 mm deeper, the corneal radius of curvature 0.10 mm greater (i.e., flatter), refraction more negative by 0.47 D (-0.76 D versus -0.29 D), and axial length-to-corneal curvature radius (AL-CR) ratio higher, after analyses controlling for age, gender, parental myopia, reading, school, and weight. The associations of height with refractive error and AL-CR ratio were significant in girls but not in boys. Heavier and more obese children had refractions that were more hyperopic (P = 0.01, P = 0.08), after analyses controlling for age, gender, parental myopia, reading, and school (height was also controlled for if weight was evaluated). This association was present in boys but not in girls. CONCLUSIONS: Controlling for age, gender, parental myopia, reading, school, and weight showed that taller Singapore Chinese children had eyes with longer axial lengths, deeper vitreous chambers, flatter corneas, and refractions that tended toward myopia. In multivariate analysis, eyes in children who were heavier or who had a higher BMI tended to have refractions that were more hyperopic, and eyes in heavier children had shorter vitreous chambers. Differences between the present results and a recent report in Singapore adults suggest either a cohort effect or a potential influence of systemic endocrine or metabolic factors during childhood on refractive development.

Biometry↗
PubMedDate not supplied

Excimer laser photorefractive keratectomy for hyperopia.

OBJECTIVE: Excimer laser photorefractive keratectomy (PRK) has been shown to be an effective method in the treatment of refractive errors, especially myopia. We evaluated prospectively the efficacy, predictability, stability, and safety of excimer laser PRK in the treatment of hyperopia. METHODS: Thirty-four hyperopic eyes were treated with an Aesculap-Meditec (MEL 60) excimer laser. The patients were divided into two groups. In the low-moderate hyperopia group, baseline spherical equivalent refraction was between +1.50 and +6.00 diopters (D) (mean, +4.20 +/- 1.30 D) and in the high hyperopia group between +6.25 and +9.75 D (mean, +7.70 +/- 1.30 D). Follow-up visits occurred 1, 3, 6, and 12 months after surgery. RESULTS: One-year results were available for a total 27 eyes (79%): 15 eyes with low to moderate hyperopia and 12 eyes with high hyperopia. One year after PRK in the low-moderate group, six eyes (40%) had a refractive error within +/- 1.00 D of emmetropia, but in the high hyperopia group only two eyes (17%) were within +/- 1.00 D of emmetropia; three eyes (20%) and one eye (8%) were within +/- 0.50 D, respectively. The stability of the refractive change was better in the low to moderate hyperopia group; in the high hyperopia group there was still some regression after 6 months. At 12 months, 10 eyes (67%) in the low-moderate and one eye (8%) in the high hyperopia group had postoperative uncorrected visual acuity of 20/40 or better. One eye in the low-moderate hyperopia group saw 20/20 without correction. Only one eye lost two lines of spectacle-corrected visual acuity. Haze was more intense in the high hyperopia group, but it did not reduce visual acuity. No vision-threatening complications were observed. CONCLUSIONS: When low to moderate hyperopia up to +6.00 D is treated, excimer laser PRK with the Aesculap Meditec MEL60 laser is safe and moderately effective, and refraction stabilizes after 3 months in most eyes. However, PRK is not sufficient to treat high hyperopia in an effective and predictable way.

Adolescent↗
PubMedDate not supplied

Initial human experience with Permalens myopic hydrogel intracorneal lens implants.

BACKGROUND: Previous nonhuman primate experimentation has demonstrated the successful use of Permalens hydrogel intracorneal lens implants for the correction of hyperopic and myopic refractive errors. This article documents the first human experience with myopic Permalens hydrogel intracorneal lens implants. METHODS: In this article, we report an 18-month follow up on five patients implanted with minus power hydrogel intracorneal lenses. All surgery and follow-up examinations were performed in Bogota, Columbia. The mean preoperative spherical refraction was -14.00 +/- 5.00 diopters (range, -9.5 to -19.00 D). RESULTS: Corrections of up to 13.00 D were achieved. Corrections deviated from the predicted correction by a mean of -5.00 +/- 2.10 D (range, -2.80 to -8.00 D). No significant surgical or postoperative complications were noted. Visual recovery was rapid, usually achieving maximum acuity within 1 month. CONCLUSIONS: Successful myopic refractive changes were accomplished in all five human subjects. The major problem with the study to date has been a significant undercorrection of the preoperative refraction. We anticipate that further empirically derived relationships between hydrogel lens power and refractive change will allow a more accurate prediction of refractive result. Also, the ability to surgically interchange myopic hydrogel inlays should allow correction of any residual refractive errors.

Corneal Stroma↗
PubMed2004

Changes in astigmatism after congenital cataract surgery and intraocular lens implantation: a comparative study.

OBJECTIVE: To evaluate the postoperative changes in astigmatism in the pseudophakic eyes of children who underwent 1 of 3 different types of surgical incisions for congenital cataract extraction with intraocular lens implantation, and in whom astigmatism of at least 3 diopters (D) was recorded 1 week after the operation. METHODS: We retrospectively reviewed the medical records of all the children in our department who had undergone surgery for nontraumatic cataract between 1992 and 2001. Cataract surgery with intraocular lens implantation was performed using 1 of 3 types of surgical incisions: a limbal incision, a scleral tunnel, or a clear corneal incision allowing the use of a foldable intraocular lens. In 28 children (32 eyes) aged 2 months to 11 years (mean +/- SD, 4.7 +/- 3.4 years), astigmatism of 3 D or more was found when assessed 1 week after surgery. The refraction was measured and recorded again 3 months and 5 months after surgery. The paired t test was used to compare the outcome variables. MAIN OUTCOME MEASURES: Refractive error 1 week, 3 months, and 5 months after surgery. RESULTS: Mean +/- SD astigmatism 1 week postoperatively was 5.8 +/- 2.2 D, 5.1 +/- 2.1 D, and 4.0 +/- 1.3 D in groups 1, 2, and 3, respectively. Thereafter, the astigmatic component of the refractive error underwent a spontaneous decline, reaching mean +/- SD values of 0.9 +/- 1.0 D, 1.6 +/- 1.6 D, and 1.0 +/- 0.8 D, respectively, in the 3 groups 5 months after the operation. The difference between the mean values at 1 week and at 5 months in each group was statistically significant (P <.001 in group 1; P =.01 in group 2; and P<.001 in group 3). CONCLUSION: Children who underwent extraction of congenital cataract and intraocular lens implantation by different surgical techniques showed a significant spontaneous reduction in astigmatism postoperatively.

Astigmatism↗
PubMed2006

Retinoschisis at macular area in highly myopic eye by optic coherence tomography.

PURPOSE: To improve our understanding of macular schisis in highly myopic eyes. METHODS: From 2002.6-2003.12, the highly myopic eyes (> 6D) which has macular schisis found by OCT at our hospital were included in the study. Each eye then received further examinations including visual acuity, refractive error and ultrasonography. Then the results were analyzed to find the characteristic of the entity. RESULTS: During that period, OCT found macular schisis in 38 highly myopic eyes from 36 patients. Their vision was low, and their average axial length and refractive error were 29.6mm and -10.5D respectively. The appearance and the area of the schisis are different among the eyes. But the schisis can be largely divided into two types: inner and outer schisis. They can exit independently or concurrently in the same eye. And the schisis was often accompanied by other macular findings, like retinal detachment, macular hole. CONCLUSION: Macular schisis in highly myopic eyes is not uncommon in the clinic. OCT is useful in its diagnosis.

Female↗
PubMed1997

Wavelength-dependent magnification and polychromatic image quality in eyes corrected for longitudinal chromatic aberration.

Theoretical calculations using a simple model eye in combination with achromatizing lenses or artificial pupils show that correcting wavelength-dependent refractive error or its effects can exaggerate wavelength-dependent magnification by up to a factor of 7. These calculations are confirmed experimentally, and their effects on retinal image quality are modeled. Because of the increased wavelength-dependent magnification, gains in polychromatic image quality produced by correcting wavelength-dependent refractive error (or minimizing its effects with small pupils) are generally restricted to a small region of the retina.

Color Perception↗
PubMed2005

Hyperopia and educational attainment in a primary school cohort.

BACKGROUND: Vision screening addresses the visual impairments that impact on child development. Tests of long-sightedness are not found in most school screening programmes. The evidence linking mild-moderate hyperopia and lack of progress in school is insufficient, although strengthened by recent findings of developmental problems in infants. AIMS: To report on the relation between hyperopia and education test results in a cohort of primary school children. METHODS: A total of 1298 children, aged 8 years, were screened for hyperopia on the basis of fogging test results. School test results (NFER and SATs) were compared between groups categorised by referral status and refractive error. RESULTS: A total of 166 (12.8%) fogging test failures were referred for ophthalmic assessment. Ophthalmic tests on 105 children provided an accurate diagnosis of vision defects, for reference to their education scores. Fifty per cent of the children examined by optometrists required an intervention (prescription change, glasses prescribed, or referral). Mean (95% CI) NFER scores of children with refractive errors (summed for both eyes) >+3D (98.4, 93.0-103.8, n = 32) or >+1.25D (best eye) (99.3, 93.0-105.6, n = 26) were lower than the respective scores of children with a less positive refractive state (104.8, 100.7-108.9, n = 43) (103.6, 99.7-107.4, n = 49), the non-referred group, and total sample. The SATs results followed a similar trend. A high proportion of the fogging test failures (16%) and confirmed hyperopes (29%) had been referred to an educational psychologist, and the latter group contributed substantially to the poor education scores. CONCLUSIONS: The results of this study provide further evidence for a link between hyperopia and impaired literacy standards in children.

Analysis of Variance↗
PubMed2004

Flap lift for LASIK retreatment in eyes with myopia.

PURPOSE: To analyze the results achieved with LASIK retreatment after lifting the original flap in a large series of patients. DESIGN: Retrospective, noncomparative, interventional consecutive case series. PARTICIPANTS: Two thousand four hundred twenty-two consecutive eyes undergoing LASIK surgery for myopia, including 334 eyes submitted to flap lift for LASIK retreatment. MAIN OUTCOME MEASURES: Uncorrected visual acuity, best-corrected visual acuity, refractive error, and complications. RESULTS: LASIK retreatment was performed in 334 eyes (14%), and the mean time between initial procedure and retreatment was 8.2+/-6.2 months. The mean spherical equivalent (SE) improved from -1.2+/-0.6 diopters (D) (range, -4.2 to +1.2 D) before retreatment to +0.2+/-0.4 D (range, -3.1 to +1.1 D) after the retreatment. The uncorrected visual acuity (UCVA) after retreatment was 20/20 or better in 58% and 20/40 or better in 92% of eyes. The mean SE was within +/-1.0 D in 96% of the patients and within +/-0.5 D in 80.5% after retreatment. Eighteen eyes (5%) lost 1 line of best-corrected visual acuity, and 4 eyes (1%) lost 2 lines. CONCLUSIONS: LASIK retreatment surgery performed by relifting the flap was a useful procedure for correcting residual refractive errors after the primary LASIK procedure. It provided good uncorrected visual acuity, predictable results, good refractive stability, and few complications.

Adolescent↗