Infrared Choroidal Reflectance Camera for the Detection of Childhood Cataract
Condition: Childhood Cataract
MeSH terms: Cataract
Study type: Observational

Summary: 
      Sensitivity and specificity of current screening methods for childhood cataracts is poor.
      This results in delayed diagnosis and management which can decrease the visual prognosis
      following cataract surgery. It also results in many false positives with resultant
      unnecessary healthcare costs in specialist paediatric ophthalmology services. This study
      compares the accuracy of cataract screening using infrared light compared to white light in a
      population of children attending eye clinic.
    

Detailed description: 
      All babies born in the United Kingdom (UK) undergo eye screening to enable the early
      diagnosis and management of childhood cataract, a treatable but potentially blinding
      condition affecting 1 in 2000 newborns. The current technique involves the assessment of the
      "red-reflex" - the orange/red glow in the pupil seen during ophthalmoscopy (or flash
      photography) due to reflectance of light from the back of the eye. In reality, testing can be
      technically difficult because the pupil constricts to light during the examination and,
      particularly in babies of Asian and Afro-Caribbean ancestry, the red-reflex can be dim due to
      the effect of ocular pigmentation. As a result less than 50% of congenital cataracts are
      currently identified up by screening. Early visual experience is required for good visual
      development and a delay in the surgical management of cataracts results in sub-optimal visual
      development and visual impairment.

      There are theoretical advantages to using Infrared (IR) light rather than white light to
      assess choroidal reflectance, including avoidance of pupil constriction. The study aims to
      determine if the assessment of the IR-reflex, using a prototype device, rather than the
      red-reflex, using a direct ophthalmoscope, improves screening accuracy in the detection of
      ocular media opacities in a pathology enriched childhood cohort.

      Eligible children attending an eye clinic will be screened for cataract by a medical student
      (masked to the pathology) using the existing standard direct ophthalmoscope technique for
      red-reflex assessment and IR-reflex assessment using the prototype imaging device. A gold
      standard examination by an ophthalmologist will follow the screening examinations.
      Sensitivity and specificity of each screening technique will be calculated and compared.
    

Intervention name(s): Red-reflex assessment; Infrared-reflex assessment
Intervention type(s): Diagnostic Test; Diagnostic Test
Intervention description(s): The red reflex was examined in the standard manner using direct ophthalmoscope by medical student examiner; The infrared reflex was examined using a modified smart phone camera by a medical student examiner
Observational model: Case-Crossover
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Infants and children from 1 month to 5 years of age attending a specialist paediatric
        ophthalmology clinic with or without known cataracts.