Kabuki syndrome

Ocular abnormalities are among the most specific and recognizable features in patients with Kabuki syndrome (KS). Most patients typically exhibit these three physical characteristics that strongly suggest this condition: 

1. Wide and long palpebral fissures 

2. Eversion of the outer part of the lower eyelid (similar to when the lower eyelid is everted for eyeliner application) 

3. Prominent, wide, arched eyebrows with sparse hair and a notch in the outer third (as if they have a scar) 

Other ocular findings occurring in more than one-third of individuals with KS include blue sclera, strabismus, ptosis, coloboma, and corneal abnormalities. Additionally, optic nerve hypoplasia, cataracts, Duane anomaly, retinitis pigmentosa, and Marcus Gunn phenomenon can also be observed. However, severe visual impairment is rare. 

In children with KS, various ocular abnormalities are described schematically. Here are some of the most frequently reported: 

• The optical part: Refractive errors, including both myopia and hyperopia, may appear. Rarely, lens opacification, known as cataract, may be observed. 

• The "electrical" part: Both optical and electrical components can present colobomas, which refer to the partial absence of normal tissue in the eye or surrounding areas. This can involve the eyelid, iris, lens, macula, optic nerve, uvea, or choroid-retina. Although infrequent, the retina may exhibit retinitis pigmentosa, leading to progressive vision loss. The optic nerves can also appear small, indicating optic nerve hypoplasia. 

• The motor part: This is one of the most common symptoms, with strabismus occurring due to hypotonia of the muscles responsible for coordinated eye movement. The partial or complete drooping of one of the upper eyelids is called ptosis and can occur in patients with KS.