bubble_chart Overview

The literature has different names for this disease, such as sex-linked hereditary juvenile retinoschisis, congenital vascular veils in the vitreous, juvenile retinoschisis, and so on. The splitting occurs in the nerve fiber layer, with the raised anterior wall consisting of the inner limiting membrane of the retina and part of the nerve fiber layer.

bubble_chart Etiology

Congenital retinoschisis is a sex-linked hereditary disease. The causes are speculated as follows: one is congenital abnormalities in the innermost layer of the retina, particularly a genetic defect at the inner end of Müller cells attached to the inner limiting membrane; the other is abnormalities in the vitreous cortex, leading to traction on the retina. The condition is congenital and typically discovered around the age of 10 due to poor vision in one or both eyes, strabismus, vitreous hemorrhage, or through family investigations prompted by an index case. It is almost exclusively seen in male children and is rare in females. It usually affects both eyes, with symmetrical schisis locations.

bubble_chart Clinical Manifestations

Retinal splitting is prone to occur in the lower fundus, especially in the inferotemporal region, presenting as a large cystic elevation from the equator to the far periphery, which is the separated inner layer of the retina. The posterior edge forms a clearly defined convex surface, while the anterior edge does not reach the ora serrata. The anterior split is thin and translucent, with retinal vessels running along it, often showing white lines or parallel white sheaths. The retina often exhibits degeneration and pigmentation. After the rupture of the anterior wall, multiple round or oval large holes appear. On the cystic posterior wall (i.e., the outer layer of the neuroepithelium), there are snowflake-like white spots, and sometimes retinal vessel projections can be seen.

When splitting occurs in the macula, it is called macular retinoschisis. Visual impairment is present from the beginning. Initially, pigmented streaks in the macula can be seen, with star-shaped pigment loss, developing into radial cystic folds centered on the fovea. These gradually merge to form a doughnut-shaped inner layer retinal split.

Congenital retinal splitting, whether occurring in the periphery or the macula, results in significant visual impairment, with more than half of cases having vision less than 0.3, and macular cases having even worse vision. The visual field shows absolute defects corresponding to the split. The ERG a-wave is normal, while the b-wave is reduced.

bubble_chart Treatment Measures

The lesions of this disease are almost static, so no treatment is necessary. Surgery is not only ineffective but also harmful. When complicated by retinal detachment, scleral buckling can be performed. When the anterior wall of the split ruptures into a circular shape, vitreous hemorrhage may sometimes occur due to the rupture of retinal vessels. To prevent this, some advocate using laser photocoagulation on the vessels, but the effectiveness is also unreliable.

bubble_chart Prognosis

The disease generally does not progress or progresses very slowly. Progression mainly occurs between the ages of 5 and 10, and development ceases after the age of 20.