In vivo quasi-elastic light scattering detects molecular changes in the lenses of adolescents with Down syndrome.

Down syndrome (DS) is the most common chromosomal disorder in humans. DS is associated with increased prevalence of several ocular sequelae, including characteristic blue-dot cerulean cataract. DS is accompanied by age-dependent accumulation of Alzheimer's disease (AD) amyloid-ß (Aß) peptides and amyloid pathology in the brain and comorbid early-onset Aß amyloidopathy and colocalizing cataracts in the lens. Quasi-elastic light scattering (QLS) is an established optical technique that noninvasively measures changes in protein size distributions in the human lens in vivo. In this cross-sectional study, lenticular QLS correlation time was decreased in adolescent subjects with DS compared to age-matched control subjects. Clinical QLS was consistent with alterations in relative particle hydrodynamic radius in lenses of adolescents with DS. These correlative results suggest that noninvasive QLS can be used to evaluate molecular changes in the lenses of individuals with DS.

Visual and ocular motor outcomes in children with posterior fossa tumors.

PURPOSE: To describe the clinical characteristics and visual and ocular motor outcomes of a large cohort of pediatric patients treated for tumors of the posterior cranial fossa. METHODS: The medical records of all patients with posterior fossa tumors evaluated by the ophthalmology services at two large tertiary care academic hospitals between 2005 and 2011 were reviewed retrospectively. Data abstracted for each study patient included demographic information, presenting signs and symptoms, pathologic diagnosis, and results of the most recent ophthalmology examination. RESULTS: A total of 139 patients were included. Visual outcomes were categorized as "good" (bilateral acuity of 20/20-20/40) in 101 patients (72.7%), "fair" (<20/40-20/200 in one or both eyes) in 12 patients (8.6%), or "poor" (<20/200 in one or both eyes) in 9 patients (6.5%). Patients with medulloblastoma and ependymoma had a significantly greater risk of a poor or fair visual outcome than those with juvenile pilocytic astrocytoma (both P < 0.05), independent of age and sex. Thirty-two patients (23.0%) developed nystagmus, and 59 patients (42.4%) developed strabismus. Twenty-four patients (17.3%) underwent eye muscle surgery for persistent strabismus. CONCLUSIONS: The majority of patients had good visual outcomes, although ocular motor abnormalities were common. Tumor type was a significant risk factor for permanent vision loss.