Patching for Lazy Eye: Trial to Evaluate Daily Patching Amounts

Amblyopia Clinical Trial

Official title:

Randomised Occlusion Treatment of Amblyopia Study (ROTAS): Trial of Maximal Vs Substantial Doses of Occlusion to Evaluate Visual Outcome for Children With Amblyopia

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00274664
• Other study ID #: ROTAS-091206
• Secondary ID: Fight for Sight:
• Status: Completed
• Phase: Phase 1
• First received: January 9, 2006
• Last updated: January 9, 2006
• Start date: February 2002
• Est. completion date: May 2005

Study information

• Verified date: December 2005
• Source: City University, London
• Contact: n/a
• Is FDA regulated: No
• Health authority: United Kingdom: National Health Service
• Study type: Interventional

Clinical Trial Summary

Amblyopia (‘lazy eye’) is the commonest visual disorder of childhood and is caused by an interruption to visual development. Occlusion of the better eye by patching is the mainstay of treatment, so forcing use, of the affected eye. We have little understanding of how much treatment is required for improvement, so occlusion may continue for many months. This is both demanding for the child and family as a whole. Treatment outcome is frequently unsatisfactory. Compliance is often poor, thus we do not know precisely how much treatment the child actually receives or how much is required.

To overcome this, we have designed an instrument that permits us to measure occlusion: an occlusion dose monitor (ODM) which provides an objective record of how much occlusion a child actually receives. Recently we have observed that 75% of improvement induced by occlusion occurs in the first four weeks of treatment. In this study we explore the possibility that by intensive treatment the period of amblyopia therapy can be shortened – i.e. treatment will be more efficient, more effective, and more ‘family-friendly’. The study hypothesis is that 12 hours/day of patching is more effective than 6 hours/day.

Description:

The identification and subsequent management of amblyopia are major consumers of health service resource, and within the hospital sector account for around 80-90% of visits to the children’s eye service. Occlusion of the better eye is the mainstay of treatment and because we have little understanding of the dose-response relationship this may continue for many months and sometimes for many hundreds of hours. This is demanding for the child and family as a whole and yet the outcome is frequently unsatisfactory. Currently, there is no reliable data on the kinetics of visual improvement, so occlusion tends to be prescribed on an ad hoc basis. Recent pilot research has shown that 75% of the treatment-generated improvement occurs within the first 4 weeks when 6 hours/day occlusion is prescribed.

In this study we explore the possibility that by intensive treatment the period of amblyopia therapy can be shortened – i.e. made both more efficient and hopefully more effective. The purpose of the present study, the Randomized Occlusion Treatment of Amblyopia Study (ROTAS), is to compare two frequently employed patching regimens: ‘substantial’ (6 hrs/day) against ‘maximal’ (12 hrs/day) patching. Our experimental design incorporates objective occlusion monitoring and is able to discriminate the beneficial effect of refractive correction from that of occlusion. The study comprises three phases: ‘baseline’, ‘refractive adaptation’ and ‘occlusion.’ Our aim is to provide guidelines for patient management based, for the first time, on experimentally determined and statistically verifiable relationships between treatment and outcome.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 100
• Est. completion date: May 2005
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 3 Years to 8 Years

Eligibility

Inclusion Criteria:

• 3 to 8 years of age;

• Presence of anisometropia and/or strabismus;

• inter-ocular acuity difference of at least 0.1 logMAR

• parental consent

Exclusion Criteria:

• history of previous occlusion therapy

• ocular pathology

• learning difficulties

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment

Related Conditions & MeSH terms

• Amblyopia

Intervention

Device:
• 6 hours occlusion by patching

• 12 hours occlusion by patching

Locations

Country	Name	City	State
United Kingdom	Hillingdon Hospital	London	Middlesex
United Kingdom	St Marys Hospitals	London	Greater London

Sponsors (2)

Lead Sponsor	Collaborator
City University, London	Imperial College London

Country where clinical trial is conducted

United Kingdom, 

References & Publications (6)

Moseley MJ, Stewart CE, Fielder AR, Stephens DA; MOTAS cooperative. Intermediate spatial frequency letter contrast sensitivity: its relation to visual resolution before and during amblyopia treatment. Ophthalmic Physiol Opt. 2006 Jan;26(1):1-4. — View Citation

Stewart CE, Fielder AR, Stephens DA, Moseley MJ. Design of the Monitored Occlusion Treatment of Amblyopia Study (MOTAS). Br J Ophthalmol. 2002 Aug;86(8):915-9. — View Citation

Stewart CE, Fielder AR, Stephens DA, Moseley MJ. Treatment of unilateral amblyopia: factors influencing visual outcome. Invest Ophthalmol Vis Sci. 2005 Sep;46(9):3152-60. — View Citation

Stewart CE, Moseley MJ, Fielder AR, Stephens DA; MOTAS Cooperative. Refractive adaptation in amblyopia: quantification of effect and implications for practice. Br J Ophthalmol. 2004 Dec;88(12):1552-6. — View Citation

Stewart CE, Moseley MJ, Fielder AR. Defining and measuring treatment outcome in unilateral amblyopia. Br J Ophthalmol. 2003 Oct;87(10):1229-31. — View Citation

Stewart CE, Moseley MJ, Stephens DA, Fielder AR. Treatment dose-response in amblyopia therapy: the Monitored Occlusion Treatment of Amblyopia Study (MOTAS). Invest Ophthalmol Vis Sci. 2004 Sep;45(9):3048-54. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	The primary outcome measure was logMAR visual acuity, measured 6-weekly for 18 weeks in refractive adaptation phase. In occlusion phase measured 2-weekly until no further gains