Monofixation Syndrome Treatment & Management
- Author: Balaji K Gupta, MD; Chief Editor: Hampton Roy, Sr, MD more...
Monofixation syndrome is often the desired result of strabismus surgery.
If a manifest strabismus is present, it is small and cosmetically acceptable.
Monofixation syndrome allows for a higher likelihood of diplopia-free long-term alignment.
Monofixation syndrome with esotropia of less than 8 prism diopters is more stable than monofixation syndrome with exotropia of less than 8 prism diopters.
Treatment is given for any associated amblyopia in accordance with standard ophthalmic principles.
Amblyopia in children should be treated with appropriate spectacle correction. A careful cycloplegic refraction should be performed to check for anisometropia.
Occlusive patching or optical penalization should be considered as the clinical situation warrants. The amount of occlusive patching is dependent upon many factors, including age, density of amblyopia, and underlying etiology. In cases of mild amblyopia secondary to anisometropia, part-time occlusion may be all that is needed.
Optical penalization is a method of amblyopia treatment. Optical penalization relies on optically blurring the image of the preferred eye. The most common method relies on using atropine 1% ophthalmic solution in the preferred eye.
Decompensated monofixation syndrome
Older patients with monofixation syndrome may develop double vision if their fusional status decreases. This is termed decompensated monofixation syndrome.
This is less likely in patients treated earlier in childhood, those with no manifest strabismus, and patients with monofixation due to anisometropia.
Decompensated subjects have demonstrated worse horizontal fusional amplitudes, greater torsional fusional amplitudes, and a higher likelihood of having small vertical strabismus than patients with stable monofixation syndrome.
In symptomatic patients, treatment ranges from correcting refraction, orthoptic exercises, prisms, and strabismus surgery. The majority of patients can be successfully returned to a monofixation state.
Heterotropia is cosmetically acceptable, so patients rarely need surgery. Monofixation syndrome tends to stabilize the alignment, thereby decreasing the need for further surgery, with over 90% of patients having stability of alignment over the first 2 decades of follow up.
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