Abnormal Head Posture While Watching TV: Could There Be A Visual Problem?


tv-head-posture

I won’t say it’s the most common symptom that prompts a visit to the eye doctor.  But I’ve heard parents express concern about their child adopting an abnormal head posture when watching TV often enough, that a new study about it in the International Journal of Ophthalmology caught my eye:

Binocular vision and abnormal head posture in children when watching television

From their conclusion: “Early detection of clinically significant nonstrabismic vergence anomalies is important. Without treatment, some of these may decompensate and become strabismic, resulting in the loss of stereopsis and the development of suppression. We therefore suggest that children with an AHP must be carefully evaluated. Besides well-known causes, such as strabismus and refractive errors, anomalous binocular function should be considered.”

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6 thoughts on “Abnormal Head Posture While Watching TV: Could There Be A Visual Problem?

  1. Good that Ophthalmology is aware of the symptom. But in my experience, most of these children do not have a gross hidden tendency for an eye to deviate (phoria). They typically have the reduced flexibility between focusing (accommodation) and eye-teaming found and treated in the convergence insufficiency study. Since surgeons are more likely to think gross convergence and phorias, and developmental optometrists are more likely to think about flexibility, a child who turns his head to avoid having to use his two eyes together would likely benefit from seeing a developmental optometrist.

    • Thanks for sharing your thoughts, David. As often as I agree with you, I’ll choose to disagree on this one. In my experience, many of these children have subtle anomalies in BV vectors of space. Particularly when yo test them with a Maddox Rod/Risley Prism combo in free space, you’ll find their alignment varies significantly and the head posture they adopt reflexively is the one that minimizes the free space phoria. I’m particularly interested in the parental report that the child naturally sits toward one side; or at a certain angle; or holds their head a certain way. Unlike screen interaction with personal devices that are within arm’s length, TV watching is unique in that there is no direct motor interaction with the body and the ensuing action on the screen. That is, in contrast with keyboard, swiping, or tablet drawing, there is not feedback, between motor action and the screen stimuli. It’s all on the visual system in isolation of traditional motor aspects of the body. I also watch carefully when the child is reading letters on the Snellen Chart OU, vs. when doing distance BV tasks. I look for them going into the AHP (using the article’s terms) when doing hectographic slide testing, Fixation Disparity, Stereopsis, and Worth 4 Dot. I tend to place more emphasis on these distance aspects of BV in these cases than I do in cases where everything’s honkey-dorey at distance and the parental concern revolves are reading, writing, etc. Is there a particular prism power/direction/vector/split between OD/OS that influences the AHP? And/or do we want to emphasize things like Brock String distance with head tilts/torques/turns? Relatively little of this relates to accommodative-vergence balance.

      • I agree with everything you wrote, Len. I so a nine field cover test on these cases, but a Maddox rod would be a better approach. Our basics skills program includes distance and near SILO, central and peripheral work, rotating targets on orthoptic and chiastopic fusion, and the head tilts typically vanish. I liked your protocol, especially oblique prism work and exploring cyclos. Sometimes we do infinity walk with distance VTS4 stereo targets. I will consider this more often on these types of cases. Thanks for the suggestions. It was a good time to disagree with my oversimplification.

      • Like your approach to using Maddox Rod in space and observing postural component. The organism moves along lines of stress to reduce stress. Voluntary reporting of signs comes only as the limits of the adaptation are reached. Signs appear first. Have you tested the body adaptations under artificially induced stress?

    • Sure, Cheryl. There are six basic principles here emphasizing distance cyclofusional vergence ranges:

      1) free space targets that permit torque and rotation – there are many variations of orthoptic and chiascopic fusion targets. Eccentric Circles and life savers are the most common. The key is to use them on an overhead transparency projector to project to a distance screen. If you don’t have one, the next best thing is to do these procedures, emphasizing divergence while torquing and/or rotating the targets. We also have a variety of flat and stereo fusion stimuli with the software loaded on our NVR projected onto a blank wall.
      2) dynamic vergence stimuli – Bernell sells 3D movies with variable vergence. We happen to play it our our SVI screen.
      3) VTS-3 or VTS-4.
      4) You can take any distance fusion projection and introduce loose prism jumps. Orient the prism axes flipping between 45/135 in addition to the usual horizontal and vertical. Cyclofusional vergence ranges are rarely trained, but can and should be – particularly for AHP.
      5) Motion stimuli on TV can tax visual-vestibular integration. The theory here is that by tiling one’s head, the vestibular system is being realigned (think of this as the fluid in the bubble of a level belong realigned to match the R & L hash marks). So when you do free space fusion activities, it’s crucial to have the patient maintain fusion by engaging visual-vestiblar interaction with slow head tilt R vs. L; face turn R vs. L; and chin up vs. chin down.
      6) When in different positions of gaze (including for Brock String), be sure to incorporate cover/uncover to build reflex fusion.

      I referenced some of these ideas here:
      https://visionhelp.wordpress.com/2013/10/07/postural-skews-and-stereo-views-part-1/
      https://visionhelp.wordpress.com/2013/10/08/postural-skews-and-stereo-views-part-2/
      https://visionhelp.wordpress.com/2013/10/09/postural-skews-and-stereo-views-part-3/

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