Infrared Choroidal Reflectance Camera for the Detection of Childhood Cataract

NCT ID: NCT03035292

Last Updated: 2023-11-07

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 110 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2017-02-01
• Study Completion Date: 2017-09-01

Brief 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.

Conditions

Childhood Cataract

Study Design

• Observational Model Type: CASE_CROSSOVER
• Study Time Perspective: PROSPECTIVE

Study Groups

Children attending eye clinic

Children 1 month to 5 years of age attending paediatric ophthalmology clinic with and without cataracts. Children who had previously had intra-ocular surgery were excluded.

One eye of each child was assessed by an inexperienced screener (medical student) by red-reflex assessment using direct ophthalmoscope and infrared-reflex using a new device (CatCam). CatCam is a modified smart phone camera which images the reflection of co-axial infrared light from the ocular fundus. A cataract appears as a black silhouette on the white infrared-reflex imaged by the camera.

Sensitivity and specificity for red-reflex and infrared-reflex assessment compared to gold standard dilated ophthalmic examination by a specialised were compared.

Red-reflex assessment

Intervention Type: DIAGNOSTIC_TEST

The red reflex was examined in the standard manner using direct ophthalmoscope by medical student examiner

Infrared-reflex assessment

Intervention Type: DIAGNOSTIC_TEST

The infrared reflex was examined using a modified smart phone camera by a medical student examiner

Interventions

Red-reflex assessment

The red reflex was examined in the standard manner using direct ophthalmoscope by medical student examiner

Intervention Type: DIAGNOSTIC_TEST

Infrared-reflex assessment

The infrared reflex was examined using a modified smart phone camera by a medical student examiner

Intervention Type: DIAGNOSTIC_TEST

Eligibility Criteria

Inclusion Criteria

• All children between 1 month and 5 years of age attending paediatric ophthalmology clinic

Exclusion Criteria

• Parents / carers with poor conversant English

• Minimum Eligible Age: 1 Month
• Maximum Eligible Age: 5 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Cambridge University Hospitals NHS Foundation Trust

OTHER

Sponsor Role: lead

Responsible Party

Dr Louise Allen

Consultant Paediatric Ophthalmologist

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Louise E Allen, MD

Role: PRINCIPAL_INVESTIGATOR

Cambridge University Hospitals NHS Trust

Locations

Addenbrooke's Hospital

Cambridge, Cambridgeshire, United Kingdom

Countries

United Kingdom

References

Rahi JS, Dezateux C. National cross sectional study of detection of congenital and infantile cataract in the United Kingdom: role of childhood screening and surveillance. The British Congenital Cataract Interest Group. BMJ. 1999 Feb 6;318(7180):362-5. doi: 10.1136/bmj.318.7180.362.

Reference Type: BACKGROUND

PMID: 9933197 (View on PubMed)

Mndeme FG, Mmbaga BT, Kim MJ, Sinke L, Allen L, Mgaya E, Bastawrous A, MacLeod D, Burton MJ, Gilbert C, Bowman R. Red reflex examination in reproductive and child health clinics for early detection of paediatric cataract and ocular media disorders: cross-sectional diagnostic accuracy and feasibility studies from Kilimanjaro, Tanzania. Eye (Lond). 2021 May;35(5):1347-1353. doi: 10.1038/s41433-020-1019-5. Epub 2020 Jun 16.

Reference Type: BACKGROUND

PMID: 32546747 (View on PubMed)

Duret A, Humphries R, Ramanujam S, Te Water Naude A, Reid C, Allen LE. The infrared reflex: a potential new method for congenital cataract screening. Eye (Lond). 2019 Dec;33(12):1865-1870. doi: 10.1038/s41433-019-0509-9. Epub 2019 Jul 2.

Reference Type: RESULT

PMID: 31267092 (View on PubMed)

Provided Documents

Document Type: Study Protocol and Statistical Analysis Plan

View Document

Other Identifiers

REC17/EE/0010

Identifier Type: OTHER

Identifier Source: secondary_id

159569

Identifier Type: -

Identifier Source: org_study_id