Paediatric community vision screening--a new model

Visual Profile of Children who Passed or Failed the UK School Vision Screening Protocol

Background:

We applied the National Screening Committee vision screening protocol [pass criterion monocular acuity ≤ 0.2 LogMAR in both eyes(BE)] to children four to five years old to investigate the visual profile of children who passed/failed. Previous studies have only evaluated those failing. The aim was to derive false positive and negative values, specificity/sensitivity of the vision screening protocol for detecting significant visual defects (strabismus and/or significant refractive error) and the utility of a ‘plus blur test’ in identifying hyperopia.

Methods:

Participants included 294 children (5.2 ± 0.4 yrs). In addition to the vision screening protocol (monocular acuity–3 m crowded Keeler LogMAR letters), acuities were recorded through +2.50D and +4.00D lenses and ocular alignment and cycloplegic refractive error were assessed. Using acuity measures, participants were classed as passing/failing the screening protocol. Each participant was also classed as having a strabismus and/or significant refractive error (hyperopia ≥ +4.00DS; myopia ≤ –0.50DS; astigmatism ≤ –1.50DC; anisometropia ≥ +1.50DS) or no significant visual defects.

Results:

Of the 284 children who completed all tests, 27.8% failed to achieve 0.2 LogMAR in BE. The acuity pass/fail criterion had a sensitivity of 70.4% and specificity of 82.2% for detecting strabismus and/or significant refractive error. Of those who failed, 51.9% (n = 41/79) had no strabismus and/or significant refractive error (false positives). Of those who passed, 7.8% (n = 16/205) had visual defects (false negatives). The ‘plus blur tests’ improved sensitivity in detecting significant refractive error (+2.50D & +4.00D 90.7%) but significantly reduced specificity (+2.50D = 65.2%; +4.00D = 60.9%).

Conclusions:

School-entry vision screening is reasonably sensitive and specific for detecting strabismus and/or significant refractive error. Most children with visions poorer than 0.2 LogMAR need refractive intervention, and the majority of the remainder are likely false positives for significant visual defects. One in 13 children who pass have either strabismus and/or significant refractive error (7.8%). The inclusion of a ‘plus blur test’ was not a useful addition to the vision screening protocol.

Eye and vision defects in under-five-year-old children in Oman: A public health intervention study

Purpose:

To identify under-five-year-old children with vision or ocular defect in two provinces (Wilayats) of central Oman in 2006.

Study Design:

Public health intervention study.

Materials and Methods:

Ocular examination in Manah Wilayat was conducted by nursing staff of the primary health center (PHC) and in Mudhaiby Wilayat was conducted by a trainee Omani optometrist. Abnormal sized eyeball, strabismus, nystagmus and white pupil were recorded. Visual acuity was tested by LOGMAR chart with Lea's symbols in children >2 years of age and preferential viewing was assessed by Lea's grating paddle or 'Hiding Heidi' picture in children ≤2 years age. Data was analyzed using Statistical Package for Social Studies (SPSS 12).

Result:

Among 1,520 examined children, three children had absent eyeball bilaterally and three had unilaterally absent eyeball. Strabismus and nystagmus were detected in 44 (2.9%) and 18 (1.2%) children respectively. 'Hiding Heidi' test was normal in 530/537 (87%) of children. Distant vision reading was ≥0.32 in 386/448 (86.2%) eyes. Preferential looking test suggested that half of the children had defective vision (>2cpcm). Screening at '1-2 year' and '3-4 years' age group could significantly predict eye problems (P ≤ 0.001).

Conclusion:

Eye and vision screening of under-five kids helped in detection of eye problems in early stages. Instead of universal screening, high risk population or children of '3 to 4' years for vision and '1 to 2' years for ocular abnormalities is proposed The existing health services could not detect some children with eye problems and they were identified during such screening.

The assessment and management of strabismus and amblyopia: a national audit

AIMS

To determine what systems are in place within ophthalmic services for the assessment and management of children suspected of having amblyopia and strabismus. To find out what methods are used for the assessment of these children.

METHODS

A questionnaire-based study auditing 288 orthoptic departments in the UK.

RESULTS

Responses were received from 75% orthoptic departments. Most hospitals employ more than one system for the assessment of strabismus and amblyopia, which is generally dependent on route of referral. These include 'orthoptic assessment without refraction' (66%), 'combined orthoptist and ophthalmologist assessment' (66%), while 22% have an entirely orthoptist/optometric system. Ophthalmologists are involved in the initial assessment in 145 units (67%), whereas some units involve an ophthalmologist only if response to treatment is poor (15%), or if surgery is required (6%). Fourteen per cent of units reviewed all children, with discharge criteria being based on normal visual acuity (52%), accurate visual acuity (39%) and a normal orthoptic assessment (42%). Seventy-six per cent of units review some children, commonly as a result of family history (55%), parental concern (43%), poor co-operation (30%) and young age (72%). In the absence of squint or amblyopia children are discharged at the first visit, in only 8% of units. There is considerable variation in the tests used to assess visual acuity. LogMAR-based tests (eg EDTRS) are not routinely used in 75% of units.

CONCLUSION

Different systems exist for the assessment and management of squint and amblyopia across the country. While much of this variation is to be expected given their possible aetiologies, some could be reduced to produce a more cohesive service. There is also considerable scope for rationalising the tests used to screen infants and children for amblyopia and strabismus.

Paediatric community vision screening with combined optometric and orthoptic care: a 64-month review

We report a new model of community-based secondary vision screening and demonstrate that a high proportion of children can be effectively managed in such a clinic without referral to the hospital eye service (HES). We performed a 64-month retrospective study of a secondary vision screening clinic providing the combined skills of an optometrist and orthoptist in a community setting. Particular attention was given to the diagnosis and management of children not referred to the HES. During this period, 1755 children were sent appointments and 74% (1300) attended the clinic. The community orthoptist and school nurses referred 53% of the patients and health visitors, general practitioners and community medical officers made 32% of the clinic referrals. Spectacles were prescribed for 41% of the children and 8% were prescribed patching. Sixteen per cent of the children were referred on to the HES. This model of care using the combined expertise of the orthoptist and optometrist is able to diagnose and manage the majority of children who have failed primary vision screening and avoids unnecessary referrals to the HES.

Vision screening in central Iowa

This study assessed the vision-screening practices of all preschools and elementary schools during the spring of 2000 in the Heartland Area Education Agency (AEA) in central Iowa. Surveys were returned by 7% of the preschools and 56% of the elementary schools. Survey questions were drafted based on recommendations from the Iowa Vision Screening Program Guidelines, which were distributed to all Iowa school districts in 1997. Areas surveyed included vision-screening personnel, attainment of students' visual history, rescreening practices, referral and follow-up, and screening procedures. Survey results indicated that there is a need for improvement to standardize vision-screening procedures within Heartland AEA. Time and effort are invested in activities that are not recommended, and not enough effort is being put into recommended activities such as obtaining vision histories, rescreening to avoid overreferrals, and follow-up to make sure students receive required treatment.