Clinical Trial: Bilateral Lateral Rectus Recession Versus Unilateral Recess-Resect for Intermittent Exotropia

Study Status: Active, not recruiting
Recruit Status: Active, not recruiting
Study Type: Interventional

Official Title: A Randomized Trial of Bilateral Lateral Rectus Recession Versus Unilateral Lateral Rectus Recession With Medial Rectus Resection for Intermittent Exotropia

Brief Summary: The purpose of this study is to evaluate the effectiveness of bilateral lateral rectus muscle recession versus unilateral lateral rectus recession with medial rectus resection procedures for the treatment of basic type and pseudo divergence excess type intermittent exotropia.

Detailed Summary:

Intermittent exotropia (IXT) is the most common form of childhood onset exotropia with an incidence of 32.1 per 100,000 in children under 19 years of age. Intermittent exotropia is characterized by an exotropia that is not constant and is mainly present when viewing at distance, but may also be present at near. Normal binocular single vision (BSV) is typically present at near when the exotropia is controlled, with evidence of normal (occasionally sub-normal) stereoacuity. Although the natural history of the condition is largely unknown, many children with IXT are treated using either surgical or non-surgical interventions. The rationale for intervention in childhood IXT is that extended periods of misalignment may lead to entrenched suppression, resulting in loss of BSV. Intervention may also aim to address the social effects caused by the appearance of misaligned eyes. Many children treated for IXT are currently treated surgically.

There is poor agreement as to which type of surgery is most effective for the correction of IXT and the debate has long been related to differentiation between IXT sub-types. Based on distance-near angle disparity, IXT sub-types are classified as: 1) basic (similar magnitude of misalignment at distance and near); 2) true divergence excess (larger at distance); 3) pseudo divergence excess (initially larger at distance, but near angle increases following occlusion or with addition of plus lenses at near); 4) convergence insufficiency (larger at near). Basic and pseudo divergence excess appear to be the most common of the sub-types, and are also the types for which there is most disagreement regarding the optimum surgical approach. The two most common procedures are bilateral lateral rectus recession (BLRrec) and unilateral lateral rectus recession combined with a medial rectus resection in the same eye (R&R). Traditionally, BLRrec has been a
Sponsor: Jaeb Center for Health Research

Current Primary Outcome:

  • surgical failure as assessed by motor alignment and stereoacuity at near [ Time Frame: 3 years ]
  • Proportion of Patients with Exotropia at 8 Years [ Time Frame: 8 years after enrollment ]
  • Distance Control at 8 Years [ Time Frame: 8 years after enrollment ]


Original Primary Outcome: surgical failure as assessed by motor alignment and stereoacuity at near [ Time Frame: 3 years ]

Current Secondary Outcome:

  • distance stereoacuity [ Time Frame: every 6 months for 3 years of follow-up ]
  • monofixation status [ Time Frame: every 6 months for 3 years of follow-up ]
  • development of amblyopia [ Time Frame: every 6 months for 3 years of follow-up ]
  • health related quality of life [ Time Frame: every 6 months for 3 years of follow-up ]
  • Distance PACT at 8 years [ Time Frame: 8 years after enrollment ]
  • Proportion of Patients with Consecutive Esotropia at 8 Years [ Time Frame: 8 years after enrollment ]
  • Near stereoacuity at 8 Years [ Time Frame: 8 years after enrollment ]
  • Cumulative Proportion of Patients with Reoperation by 8 Years [ Time Frame: 8 years after enrollment ]
  • Comparison of Number of Surgeries by 8 Years [ Time Frame: 8 years after enrollment ]


Original Secondary Outcome:

  • distance stereoacuity [ Time Frame: every 6 months for 3 years of follow-up ]
  • monofixation status [ Time Frame: every 6 months for 3 years of follow-up ]
  • development of amblyopia [ Time Frame: every 6 months for 3 years of follow-up ]
  • health related quality of life [ Time Frame: every 6 months for 3 years of follow-up ]


Information By: Jaeb Center for Health Research

Dates:
Date Received: December 11, 2009
Date Started: June 2010
Date Completion: February 2022
Last Updated: April 11, 2017
Last Verified: April 2017