Cerebral visual impairment in children born prematurely

Cerebral visual impairment (CVI) is the commonest cause of impaired vision in childhood. Prematurely born children are at significant risk of damage to the brain with outcomes including cerebral palsy and low IQ. This study presents the results of an investigation of multiple aspects of visual function in a cohort of 46 prematurely born children (<37 weeks) aged 5.5 years -12.3 years and attending mainstream education, compared with an age-matched cohort of 130 term-born children. Fifteen of the 46 (33%) prematurely born children revealed behaviours corresponding to CVI on cluster analysis of a CVI questionnaire, a screening tool used to aid structured clinical history taking. In these children, abnormalities of stereoacuity, contrast sensitivity and eye movements were more frequent and in addition they were born 1½ weeks earlier and around 300g lighter on average than their unaffected peers. These children also performed worse than controls on all visual attention and perception tests except visual closure, while the remaining 31 prematurely born children performed no differently to controls. This study highlights the incidence of prematurely born children with manifest CVI related difficulties. No visual perception test or routine ophthalmic test picked out those children identified with difficulties by the CVI questionnaire. The CVI questionnaire could be an effective means of identifying children at risk of CVI

Cerebral visual dysfunction in prematurely born children attending mainstream school

&lt;p&gt;Purpose: Although premature birth is recognised as a cause of cerebral visual impairment (CVI), which can include cerebral visual dysfunction (CVD), the incidence and nature of CVD in prematurely born children is not known.&lt;/p&gt; &lt;p&gt;Methods: A prospective, controlled investigation was undertaken of forty-six, mainstream primary school children, prematurely born with gestations of 24.0–34.6 weeks, and of 130 control (term-born) children. Assessments were made of IQ, ophthalmic functions, visual perception and visual attention. Structured history-taking seeking evidence of behavioural features of CVI used a question inventory. Obstetric, neonatal and paediatric medical histories were documented from case records.&lt;/p&gt; &lt;p&gt;Results: Fifteen out of forty-six (33 %) of the prematurely born children—“cluster A”—revealed behaviours corresponding with CVD on cluster analysis of the CVI inventory. The whole prematurely born group performed worse than controls on all visual perception tests and all four visual attention tests. Children in cluster A were responsible for this effect, performing worse than controls on all visual perception and visual attention tests except visual closure, while cluster B prematurely born children performed no differently to controls.&lt;/p&gt; &lt;p&gt;Conclusions: The prevalence of CVD in these prematurely born children is between 21–47 % (95 % CI), with a pattern similar to “dorsal stream dysfunction”. Currently available perceptual tests appear to be unable to identify the specific pattern of problems noted in this group. Many studies have provided evidence of cognitive and intellectual dysfunction in prematurely born children, and it is possible that CVD is a contributor. The CVI inventory is a potential means of identifying and characterising the condition, which can be ameliorated with simple strategies.&lt;/p&gt