In a recent evaluation of subclinical markers of strabismus in children, researchers at the Mayo Clinic found that inferior oblique muscle dysfunction, anisometropia and subnormal stereopsis were most prevalent.

The team used a combination of ophthalmic exam and family history to determine the prevalence of subclinical markers for pediatric strabismus. Markers included oblique muscle dysfunction, stereopsis <60 arcsec, monofixation, nasal-temporal pursuit asymmetry, dissociated strabismus and anisometropia.

The community-based study included 1,000 children (49.8% male) aged five to 18 (mean age 10.6), of which 5.7% had strabismus and 13% had some form of phoria. Of those without strabismus, 10.9% had one or more subclinical markers. These included inferior oblique dysfunction (4.5%), anisometropia (3.9%), subnormal stereopsis (3.6%), nasal-temporal pursuit asymmetry (6, 0.6%) and monofixation (3, 0.3%).

A subclinical marker of strabismus occurred in 12.7% of the 157 nontropic children with family history of either strabismus, amblyopia or both and in 10.6% of the 786 nontropic children without a family history.

Ultimately, the researchers concluded that subclinical disorders of binocular vision occur in about 10% to 13% of children without strabismus. “Identifying these disorders among strabismic families may be useful in elucidating the genetic puzzle of childhood strabismus,” they wrote.

Mohney BG, Lepor L, Hodge DO, et al. Subclinical markers of strabismus in children 5-18 years of age. JAAPOS. May 31, 2021. [Epub ahead of print].