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Aim: To evaluate in a pilot study the use of a touchscreen test in very low birth weight (VLBW) children to explore aspects of visuo-motor behaviour, measuring spatial localisation. Results in VLBW subjects will be compared with those in children born at term. It will be investigated whether any deficits found were related to parental reports of visual function difficulties. Methods: A range of visual functions were measured and IQ estimated using subtests from a standardised test. Using a touch-screen monitor to record pointing positions, in task 1 subjects pointed to sequences of visual targets as soon as they appeared and in task 2 they pointed after a memory delay. Results: Thirty-seven VLBW subjects and 32 control subjects were recruited. On task 1 there was no difference in the pointing error magnitude between the groups. Although the errors of the VLBW group were more variable, this was not statistically significant after exclusion of VLBW subjects with IQ

Aims: To validate the design of updated optotypes to be used in the Kay picture acuity tests to improve the resolution acuity, recognition, repeatability and comparisons with gold standard logMAR acuity assessments. Methods: The study was completed in four phases. Inball phases the pictures were presented on a monitor as a single crowded optotype, with five optotypes at each visual acuity (VA) level. Phase one assessed the resolution acuity for 25 pictures, eight Landolt Csband five ETDRS letters. The recognition phase (phasebtwo) assessed children (18 months to 5 years) to determine which pictures were most commonly identified. During phase three, the resolution acuity of a reduced number of pictures and the Landolt C were reassessed to ensure that fatigue had not influenced the initial results. Phase four compared the new Kay pictures with LEA symbols and the ETDRS (part a), and repeatability of the Kay pictures and the ETDRS chart (part b). Results: 'Phase one (resolution acuity)': 50 adult subjects were tested. The mean (±SD) acuity scores achieved using each of the 25 pictures ranged from -0.123 ±0.124 to -0.308 ±0.105. The mean (±SD)bacuity for the eight Landolt C orientations was -0.059 ±0.120, and -0.128 ±0.101 for the ETDRS letters. Following this analysis, three pictures were removed. Phase two (Recognition): 420 children were assessed (54% male) using the remaining 22 pictures. Analysis resulted in the removal of 10 pictures based on the recognition levels. Phase three (resolution acuity): 43 adult subjects were tested with the remaining 12 pictures. The picture selection was reduced to six based on a combination of similar mean bias levels, recognition levels in all children and recognition levels in the youngest children. Phase four (a) (comparability): 113 adult subjects were tested. The mean bias indicated similar results between the tests. The limits of agreement for ETDRS versus Lea symbols were slightly wider than for ETDRS versus Kay pictures. Phase four (b) (repeatability): 100 adult subjects were tested. Paired 't'-test analysis demonstrated no significant difference between tests in either ETDRS ( p = 0.1) or Kay pictures ( p = 0.1). Mean bias for both tests was 0.01 logMAR with similar limits of agreement. Conclusion: The newly designed Kay picture optotypes have been shown to be reliably recognised by a paediatric population. In a six-picture test format the newly designed optotypes with single picture presentation and crowding bars have been shown to be a reliable and repeatable VA test in an adult population with good agreement with current gold standard VA assessment methods. Normative data in a paediatric population are now required.

Aims: To determine what practising orthoptists consider to be a normal AC/A ratio and on what evidence this is based. To assess which method of measurement is most commonly used and whether the ratio itself contributes to the diagnosis and management of strabismus in current practice. Methods: A prospective cross-sectional survey was designed and distributed to all orthoptists registered with the British and Irish Orthoptic Society (BIOS). The survey was web-based and consisted of 17 questions relating to the measurement of the accommodative convergence/accommodation (AC/A) ratio and its application to clinical practice. Prior to the survey being distributed nationally, a pilot survey was sent to a small group of practising orthoptists for validation. Results: There was a significant difference ( p < 0.05) in orthoptists’ perception of the normal AC/A ratio (gradient and heterophoria) compared with published research. Ninety-three per cent stated that their definition of ‘normal’ was based on either clinical experience or what they were taught during training, with the gradient method at 33 cm being most commonly used (92.79%). The AC/A ratio is widely used (either ‘always’ or ‘sometimes’) in the diagnosis of convergence excess esotropia (CXS) (97.26%) and intermittent distance exotropia (IDEX) (93.75%) and (either ‘always’ or ‘sometimes’) in the management of CXS (88.89%) and IDEX (79.02%). Conclusion: The majority of orthoptists who participated are primarily measuring the stimulus AC/A ratio clinically. There is a discrepancy between participants’ perception of a normal AC/A ratio and published research, yet the ratio is still used in the diagnosis and management of certain types of strabismus.

Aim: To review the current literature on long-term ophthalmic deficits and behavioural and/or cognitive outcomes occurring in low birth weight (LBW) children and to determine whether there is any link between the ophthalmic deficits and functional out­come. Methods: A literature search was performed focusing mainly on publications from the past 10 years. Results: LBW children are at an increased risk of a large number of ophthalmic deficits, including reduced visual functions (acuity, visual field, colour vision, stereo-acuity and contrast sensitivity), increased prevalence of strabismus and all types of refractive error. These deficits are not restricted to the smallest children; they can occur with increased frequency in nil LBW children. As a group LBNV children have increased risk of cognitive and behavioural deficits, which can affect them through­out their education. There is evidence of an associa­tion between ophthalmic outcome and many aspects of functional ability (e.g. IQ, reading ability). Further research is required to discover whether there is a common aetiology. Conclusion: The evidence discussed supports the need for long-term ophthalmic monitoring, and treatment where necessary, due to the potential impact of LBW on education and development. Currently there is no standardised approach for this. Further discussion is required to optimise the long-term care of all LBW children.