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Visual capacity and Prader-Willi syndrome

R Fox1, R B Sinatra, M A Mooney

  • 1Department of Psychology, Vanderbilt University, Nashville, Tennessee, USA.

Journal of Pediatric Ophthalmology and Strabismus
|January 2, 2001
PubMed

Insights

Ocular anomalies in Prader-Willi syndrome (PWS) are not unique. Most vision issues in PWS patients are similar to the general population, not specific to the genetic disorder.

Area of Science:

  • Ophthalmology
  • Genetics
  • Pediatrics

Background:

  • Prader-Willi syndrome (PWS) is a genetic disorder caused by chromosome 15 anomalies, affecting 1 in 10,000–20,000 individuals.
  • PWS is characterized by hypotonia, childhood obesity, hypogonadism, and intellectual disability.
  • Previous studies suggested unique ocular anomalies associated with PWS.

Purpose of the Study:

  • To investigate the hypothesis that ocular anomalies in PWS are unique to the syndrome.
  • To compare ophthalmic findings in individuals with PWS to a control group.

Main Methods:

  • Comprehensive ophthalmic examinations were conducted on individuals with PWS and a control group.
  • Genetic analysis confirmed PWS diagnosis and identified subgroups (deletion and maternal disomy).
  • Controls were matched for age, body composition, and intelligence.

Main Results:

  • No significant differences in clinical ophthalmic measures were found between PWS subgroups (deletion and maternal disomy).
  • Ocular anomaly incidence in PWS was comparable to previous reports.
  • Myopia and stereopsis differed between PWS and control groups, with maternal disomy subgroup showing greater stereopsis impairment.

Conclusions:

  • The similarity in ocular findings between PWS and control groups, except for myopia and stereopsis, suggests anomalies are not unique to PWS.
  • Many previously reported PWS ocular anomalies may stem from general population factors rather than a specific PWS ocular signature.
Abstract

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