ASD: Poor accommodative responses, refractive errors common

Children with autism spectrum disorder (ASD) are nearly 4 times more likely to exhibit clinically significant accommodative lag than their peers, notes a new study that illustrates the criticality of timely, comprehensive eye care in these individuals.

Published in the March edition of Optometry and Vision Science, the study found not only significantly poorer accommodative responses among children with ASD as compared to an age-matched control group of children without ASD, but also subtle reductions in presenting near-visual acuity and convergence in children with ASD. Such results bolster evidence that children with developmental or intellectual disabilities may go with unrecognized, untreated vision problems that could impact educational attainment and would therefore benefit from appropriate eye care intervention.

ASD, a neurodevelopmental disorder that encompasses a wide range of types and severity of symptoms, typically manifests as impairments in an individual's communication or social interactions, and repetitive behaviors or routines. Its estimated prevalence is 1.46% in the United States, generally appearing in the first two years of life.

This study, based in Northern Ireland, recruited 206 participants ranging in age from 6 to 16 years, with 128 children diagnosed with ASD (99 children with autism and 40 children with Asperger's syndrome). Each subject was assessed—while wearing their normal vision correction—using a modified Nott dynamic retinoscopy technique with an Ulster-Cardiff Accommodation Cube as a fixation target.

From this, researchers determined that one in five children with ASD exhibited clinically significant accommodative lag, as well as a flatter accommodative response profile compared to control participants. So, too, it was noted that children with ASD and a significant accommodative lag had reduced near-visual acuity compared with those of good accommodation, the study says.

"It is presently unclear why autism spectrum disorder impacts on accommodative performance, whether hypoaccommodation responds to treatment or whether information about accommodative function could inform our understanding of the neural basis for autistic traits," the study notes. "Further careful investigation of accommodative function, the near triad, and the value placed by the autism spectrum disorder visual system on the cues involved in producing an accurate accommodative response is needed."

Despite the questions raised, the findings demonstrate that patients with ASD necessitate special attention to the assessment and managing of refractive errors and other visual functions.

Examining patients with ASD, other special needs

As this research illustrates, children with developmental or intellectual disabilities have a higher rate of vision disorders and should receive a comprehensive pediatric eye and vision examination. Although clinically more challenging, visual assessment is possible in the majority of these children, and as AOA's evidence-based clinical practice guideline, Pediatric Eye and Vision Examination, states, "early identification of specific visual deficits could lead to interventions to improve the educational and occupational achievement and quality of life for these high-risk children."

Dominick Maino, O.D., professor of pediatrics/binocular vision at Illinois College of Optometry and author of the book, Visual Diagnosis and Care of the Patient with Special Needs, says doctors of optometry should always acknowledge that "autism" is not a homogenous diagnosis and more often than not, does not fully represent the patient sitting in the exam chair.

"Those with autism can be very high functioning and respond to your questions as well as anyone else. They also can be much more severely affected and require objective examination techniques," Dr. Maino says.

"I would suggest that the apparent, visible disability may not actually represent the level of cognitive involvement and that if you were to make any assumptions, that you assume every patient can do every test you want them to do. When you use this approach, you will gather much more data than if you assume your patient cannot do something."

April marks National Autism Awareness Month, a nationwide effort to promote awareness, inclusion and self-determination, and assure that everyone with ASD is afforded opportunities to achieve the highest possible quality of life—and clear, healthy vision is critical to helping reach that goal.

As such, Dr. Maino and Sue Lowe, O.D., AOA Health Promotions Committee chair, share several practice pearls for providing an eye examination to patients with special needs.

1. Do your due diligence. Develop an understanding of the patient's needs before they're in the exam chair. This includes a developmental questionnaire with patient history, concerns and type of services currently received and development history, Dr. Lowe says. Adds Dr. Maino: "The more you know, the better. I change my treatment to coincide with the patient's needs, backed up by that prior knowledge."
   
   
2. Consider patients' comfort. Make the exam experience easy and as stress-free as possible. Consider scheduling the exam at a time best for the patient, or consider allowing the patient and caregiver time to visit the practice before the examination to alleviate uncertainty.
   
   
3. Be flexible in the exam. As Dr. Maino noted earlier, let the patient prove what he or she can or cannot do when it comes to the examination. Accept that "fuzzy data" may be a reality and sometimes an examination might require you to use tools in different ways to get desired data. Be open to doing the examination in a place that's most comfortable for the patient, such as a parents' lap or the floor. Be prepared with handheld instruments, Dr. Lowe suggests.
   
   
4. Welcome collaboration. Encourage patients or parents to bring along their care team (therapists, teachers, etc.) for the pediatric eye examination to bolster a collaborative environment, Dr. Lowe says. Offer explanations not only to the patient, but also the caregiver/team, and consider a written summary of the appointment.

Read more about the ethical considerations of providing optometric care to patients with disabilities in the most recent AOA Ethics Forum case study.