Of the various autism science journals out there in peer-reviewed (La-La!) land, one journal in particular is really starting to grow on me: [The] Review Journal of Autism and Developmental Disorders.
I like this journal because it is basically systematic review and meta-analysis heaven when it comes to the quite voluminous autism research literature and seems to publish some real gems (see here for example).
Another paper from this journal caught my eye recently by Maggie Butchart and colleagues  (open-access) synthesising the collected research on "the prevalence of visual impairments in children and adults with Autism Spectrum Disorder (ASD), and the similar behavioural traits associated with both visual impairment and autism." Affiliated with the RNIB - Royal National Institute of Blind People - Scotland among other groups, the authors trawled the research literature looking at reported visual impairments in relation to the autism spectrum and provide quite a nice overview of 'where we're at' with regards to "papers published from 2000-2015."
The paper is open-access but a few comments are required bearing in mind my relative lack of knowledge on the complexities of visual impairments.
First: "Collating the evidence from six of the seven prevalence studies suggests a refractive error rate in the childhood ASD population studied at 22.9–32.7%, which is comparable with general childhood refractive error rates in 6–7 year olds at 29%, and 32.3% in 12–13 year olds." What this means is that a diagnosis of autism does not protect against the presence of refractive errors ('when the shape of the eye prevents light from focusing directly on the retina').
Second: "Estimates of childhood strabismus in the UK is 1.5 to 5.3%... but in the evidence collated in this review, the incidence of strabismus amongst autistic participants is higher at 8.3%." Strabismus, where the eyes don't align properly, seems to be a little bit more prevalent when it comes to autism compared with general population statistics. This is a topic that I've talked about before on this blog in relation to correcting such an issue with autism in mind (see here).
Finally: "There were no studies examining ophthalmic conditions and adult autistic populations who are more at risk of age-related visual impairments." Bearing in mind the search parameters included in the Butchart paper, I'm kinda dismayed that this is the current state of affairs. You'd have thought with all the money and resources being thrown into autism research that someone, somewhere might have thought more about eye health in adults with autism? Eye-tracking, reading the mind in the eyes test... the word 'eye' or 'eyes' is prominent in autism research but just not in relation to eye health it seems. And bear in mind that issues with eye health probably will affect the results of some of those autism 'eye' studies.
Eye or vision issues related to autism have often been a topic of discussion on this blog (see here and see here for examples) and so I'm glad that someone has finally brought a review of this area into the peer-reviewed arena. Screening is important; even if some of those on the autism spectrum may not always be by first sight (pardon the pun) particularly amenable to taking part in an eye exam - adjustments can and should be made.
And finally consider this: "Undiagnosed visual impairment is likely to severely impact quality of life. There is a need therefore for education and training that equip autism support practitioners with the awareness and skills to identify potential visual impairment, to refer individuals to optometry professionals if necessary, and to make necessary adjustments to service environments and support practices for individuals identified as having a visual impairment." Not much more to say really is there aside from 'make it so'.
 Butchart M. et al. Autism and Visual Impairment: a Review of the Literature. Review Journal of Autism and Developmental Disorders. 2017. Jan 5.
Butchart, M., Long, J., Brown, M., McMillan, A., Bain, J., & Karatzias, T. (2017). Autism and Visual Impairment: a Review of the Literature Review Journal of Autism and Developmental Disorders DOI: 10.1007/s40489-016-0101-1