What is Accommodative dysfunction?
Accomodative dysfunction is when a patient has a problem sustaining prolonged near focus. This is not an eyesight or refractive error problem but rather an acquired fatigue problem which produces eye strain and stress with prolonged near work.
What is causing a focusing problem?
There are four reasons for developing an accommodative dysfunction;
- poor general health (chronic fatigue syndrome, glandular fever, bad flu etc.)
- a side effect of some medications. (Ritalin, antihistamines, etc.)
- a high degree of long-sightedness or eye turn (especially esotropia).
- near point stress due to prolonged near tasks; particularly if at an age where you have not yet developed good focusing stamina to cope with it.
Note: accommodative dysfunction can even happen in the adult eye, especially if you are doing a stressful near centred task (eg new job involving more close work, study, prolonged computer work, fine sewing etc).
The symptoms associated with focusing dysfunction are usually related to the task that produces the stress, that is, prolonged near centred tasks. The symptoms may include, but are not limited to the following:
- visual stress symptoms include: red eyes, sore eyes, transient blurry vision and/or headaches
- difficulty sustaining near vision attention (may actually avoid near tasks).
- glare symptoms while doing close work, this includes pages or computer screens
- abnormal posture adaptions such as head tilt or moving work closer
1. Training spectacle lenses for all close work
- the problem is not that things are constantly blurry, the problem is that the focusing system is working too hard to keep it clear, this causes fatigue.
- the training lenses help alleviate the visual point stress
- the more they are worn for near work, the sooner the patient will have better focusing stamina, this also means that the sooner the patient will no longer need to wear glasses
2. Eye exercises (visual therapy)
Visual Therapy on its own is slow to develop accommodative (focusing) stamina for the simple reason that for every half hour of therapy that might be done at night time, the child/adult has usually been doing 5 or 6 hours of “anti-therapy” during the day (i.e. demanding close work causing accommodative fatigue).
Duration of treatment
Generally the training lenses are needed to be worn for all close work including computer work, reading, classroom work etc. They are not for outdoors, TV or for constant wear.
Golden Rule: If you can touch it with your hands you should have your training spectacles on to see it.
- most need the training spectacles for 12-18 months we can reduce or eliminate the need to wear them anymore
- we will do a 6 week review to ensure the training lenses are developing better accommodative stamina
- if there is little or no change after this time, visual therapy will also be considered, however, this is only needed in about 33% of cases
- visual therapy requires 4-6 in practice visits along with home based activities being done in between visits
Note: These are generalised guidelines and each case may need to be evaluated on the individual basis. Treatment duration will depend on the particular patient’s condition.