Wednesday, 5 December 2012

The eyes have it for autism?

Twenty-twenty @ Wikipedia 
There were a few reasons why I wanted to talk about the paper from Ikeda and colleagues* on ophthalmologic (eye) disorders noted in cases of autism.

First and foremost is my continued, unwavering, interest in all things comorbidity with autism in mind. Probably the next reason was the quite astonishing rate of ophthalmologic disorder reported by Ikeda, in "40% of patients with autism or a related disorder".

A final reason? Well without wishing to plug anyone, a friend of mine is making some waves in this whole area of vision and perception and he's talked quite a bit about the value of appropriate eye examinations for people with autism and lots of related developmental conditions, partly so as not to reflect yet another health inequality.

Indeed having very recently seen him lecture again and talk about problems with vision, face perception and descriptions of eyes, nose and mouth seemingly not being where they were supposed to be alongside faces morphing into animals and vegetables, I'm more convinced than ever about the value of looking at vision processing for some cases of autism and other conditions too.

During a past post titled: Do you see what I see? I talked about the sensory and perceptual link to autism and how even the proposed revisions to the DSM V description of autism spectrum disorders have recognised just how important issues with visual, auditory and other sensory modalities might be to cases.

The Ikeda paper is slightly different insofar as they were looking for specific issues with the eyes following a retrospective review of their caseload.

The main points:

  • Based on a total cohort of 407 pediatric attendees diagnosed with an autism spectrum disorder at a medical centre, a chart review revealed that 154 had documentation pertaining to an ophthalmologic examination by a suitably qualified person.
  • Most children were male, white and diagnosed with mild/moderate autism. Over half of the children (57%) "presented with an eye-related concern" in the majority noted by parents.
  • Results: only 40% of the cohort were cooperative for recognition visual acuity testing (the well-know eye chart test) and of those other 60% not cooperative, upwards of a third were found to have an ophthalmologic disorder. 
  • That original 40% quote used in the beginning of this post included a variety of ophthalmic issues, many of which I can't even pronounce never mind give you detailed information about. The main issues were: strabismus (irregular aligning of the eyes) (21%) and "significant refractive errors" including hyperopia (long-sightedness) and myopia (short-sightedness) as being primary.
  • Other less commonly described conditions include: nystagmus (voluntary or involuntary eye movements) and ptosis (a drooping or falling of the eyelid), and something linked to the autoimmune neuromuscular condition myasthenia gravis.

There are a few quite important points of discussion to take from this work and some other related study. Aside from reiterating the percentage of children with autism with verifiable issues with their eyes and vision (40 PERCENT), the point made about those who were least cooperative during examination carrying quite a high burden of ophthalmologic disorder is a worrying trend. That coupled with other data from this study on the role of comorbid intellectual disability (ID) also potentially being a risk factor for eye problems, really does make you sit up and think. I'm not for one minute suggesting that those in the uncooperative category are somehow cajoled into undertaking an eye examination (indeed whether it would be possible) but certainly the onus might be on the clinician and other professionals to engage in a little creative thinking about how uncooperative participants can be more readily catered for.

There is also a question about the relationship between ophthalmologic disorders and some of the various perceptual issues reported in cases of autism. Again my lack of expertise in this areas shines through as I cannot readily say whether issues like strabismus might have the potential to impact on visual perception or indeed whether some kind of cognitive correction might be at work**. I assume like everything, there is probably going to be a degree of individuality to such eye issues and any adaption made or not where timing might also be an important factor.

Meandering (a lovely word!) through the other research on ophthalmologic disorders and autism, there seems to be snippets of information about for example, various genetic conditions manifesting eye disorders and autism (see this paper by Strömland and colleagues*** for example). Such papers pose some interesting questions about whether within the autisms spectrum (plural again), there may be cases whether eye anatomy and physiology might share underlying issues (genetics, epigenetic or environmental) with the appearance of autistic characteristics**** in the same way that some people get quite excited about facial phenotypes and autism.

"Just one last thing"... I also chanced upon an interesting case series described by Pineles and colleagues***** (open-access) on something called vitamin B12 optic neuropathy presenting in cases of autism. I've kinda touched upon vitamin B12 and methlymalonic acid (MMA) issues appearing in autism in a previous post. Pineles et al suggest that a deficiency in vitamin B12 might indeed be an important correlate for things like decreased visual acuity in some cases of autism. This in itself asks a few further questions about why such deficiency might be present and indeed whether there may be some good reasons to look more closely at vitamin supplementation (thinking back to Jim Adams' study) where certain eye problems might be present as a comorbidity.

Oh, and I assume you have seen this paper?

To close, always remember Apollo Creed and the Eye of the Tiger. Respect.

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* Ikeda J. et al. Brief report: Incidence of ophthalmologic disorders in children with autism. J Autism Dev Disord. February 2012.

** Economides JR. et al. Perception via the deviated eye in strabismus. J Neurosci. 2012; 32: 10286-10295.

*** Strömland K. et al. Oculo-auriculo-vertebral spectrum: associated anomalies, functional deficits and possible developmental risk factors. Am J Med Genet A. 2007; 143A: 1317-1325.

**** Miller MT. et al. The puzzle of autism: an ophthalmologic contribution. Trans Am Ophthalmol Soc. 1998; 96: 369-385.

***** Pineles SL. et al. Vitamin B12 optic neuropathy in autism. Pediatrics. 2010; 126: e967-e970.

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ResearchBlogging.org Ikeda J, Davitt BV, Ultmann M, Maxim R, & Cruz OA (2012). Brief Report: Incidence of Ophthalmologic Disorders in Children with Autism. Journal of autism and developmental disorders PMID: 22350452