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Alteration of rod and cone function in children with Usher syndrome

Eva Malm1, Vesna Ponjavic, Claes Möller

  • 1Department of Ophthalmology, Lund University Hospital, Lund, Sweden. eva.malm@med.lu.se

European Journal of Ophthalmology
|June 15, 2010
PubMed

Insights

Usher syndrome in children shows varied retinal function and progression rates based on genetic type. Full-field electroretinography (ERG) reveals early rod-cone dystrophy with differing severity in Usher 1, 2, and 3 types.

Area of Science:

  • Ophthalmology
  • Genetics
  • Pediatrics

Background:

  • Usher syndrome is a genetic disorder causing retinitis pigmentosa and hearing impairment.
  • Understanding retinal function and progression in affected children is crucial for management.

Purpose of the Study:

  • To evaluate retinal function, phenotype, and progression rate in children with different Usher syndrome genotypes.
  • To establish the utility of full-field electroretinography (ERG) in pediatric Usher syndrome assessment.

Main Methods:

  • Full-field ERG under general and local anesthesia was performed on 14 children (2-10 years) with Usher syndrome.
  • Genetic analysis identified genotypes (Usher 1B, 2A, 3A).
  • Follow-up ERG, multifocal ERG, and optical coherence tomography (OCT) were utilized.

Main Results:

  • All Usher syndrome patients exhibited early rod-cone dystrophy on ERG.
  • Rod function declined after age 4, with severe progression in Usher 1 and 2, moderate in Usher 3.
  • Cone function was moderately reduced; multifocal ERG showed preserved central cone function, and OCT revealed discrete structural changes.

Conclusions:

  • Full-field ERG in children with Usher syndrome reveals diverse phenotypes and progression rates.
  • Retinal function varies significantly with Usher syndrome genotype during childhood.
Abstract

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