Why carry out this study?

Joubert syndrome (JS) is an autosomal recessive disorder characterized by congenital malformation of the mid-hindbrain and a large spectrum of clinical features including congenital retinal dystrophy.

The function of different retinal elements (rod, cone, bipolar cells) can be objectively evaluated by using different types (dark-adapted, light-adapted, and 30-Hz flicker) of electroretinogram (ERG) recordings.

This observational and prospective study was carried out to evaluate the retinal function (by ERG recordings) in patients with JS with (JS-RD group) or without (JS-NRD group) congenital retinal dystrophy. Our results should provide information about the possible usefulness of ERG recordings in the assessment of the efficacy of treatments targeted to improve the retinal condition.

What was learned from the study?

When compared to controls, patients in the JS-RD and JS-NRD groups showed significant abnormalities of the values of dark-adapted, light-adapted, and 30-Hz flicker ERG parameters. The ERG and visual acuity changes were not significantly correlated.

In patients with JS with or without retinal dystrophy, a dysfunction of photoreceptors and bipolar cells occurs and this can be detected by ERG recordings. ERG methods should be proposed to evaluate the effectiveness of adequate treatment aimed to improve the retinal impairment of patients with JS.