Trial of Overminus Spectacle Therapy for Intermittent Exotropia (IXT5)
Intermittent Exotropia
About this trial
This is an interventional treatment trial for Intermittent Exotropia focused on measuring Intermittent Exotropia, IXT, overminus
Eligibility Criteria
Inclusion Criteria:
- Age 3 years to < 11 years
- Intermittent exotropia (manifest deviation) meeting all of the following criteria:
At distance: intermittent exotropia or constant exotropia
o Mean distance control score of 2 points or more (mean of 3 assessments over the exam)
At near: intermittent exotropia, exophoria, or orthophoria
o Subject cannot have a score of 5 points on all 3 near assessments of control
- Exodeviation at least 15∆ at distance measured by PACT
- Near deviation does not exceed distance deviation by more than 10∆ by PACT (convergence insufficiency type IXT excluded)
- Distance visual acuity (any optotype method) in each eye of 0.4 logMAR (20/50) or better if age 3 years and 0.3 logMAR (20/40) or better if 4 years or older.
- Interocular difference of distance visual acuity ≤0.2 logMAR (2 lines on a logMAR chart)
- Refractive error between -6.00 diopters (D) standard error (SE) and +1.00D SE (inclusive) in the most myopic / least hyperopic eye based on a cycloplegic refraction performed within the past 2 months or at the end of the enrollment exam.
- If refractive error (based on cycloplegic refraction performed within past 2 months or at the end of the enrollment exam) meets any of the following criteria, then pre-study spectacles are required and must have been worn for at least 1 week prior to enrollment:
- SE anisometropia ≥1.00D
- Astigmatism ≥1.50D in either eye
- SE myopia ≥-1.00D in either eye
Pre-study refractive correction, if worn, must meet the following criteria relative to the cycloplegic refraction performed within past 2 months or at the end of the enrollment exam:
- SE anisometropia must be corrected within <1.00D of the SE anisometropic difference
- Astigmatism must be corrected within <1.00D of full magnitude; axis must be within 10 degrees.
- The SE of the spectacles must not meet the definition of substantial overminus (see exclusion criteria below)
- Gestational age ≥ 32 weeks
- Birth weight > 1500 grams
- Parent understands the protocol and is willing to accept randomization to overminus spectacles or non-overminus spectacles
- Parent has home phone (or access to phone) and is willing to be contacted by Jaeb Center staff and Investigator's site staff
- Relocation outside of area of an active PEDIG site within next 18 months is not anticipated
Exclusion Criteria:
- Treatment for IXT or amblyopia (other than refractive correction) within the past 4 weeks, including vision therapy, patching, atropine, or other penalization.
- Current contact lens wear
- Substantial deliberate overminus treatment within the past 6 months, defined as spectacles overminused by more than 1.00D SE than the cycloplegic refractive error (within 2 months or at the end of the enrollment exam)
- Prior strabismus, intraocular, or refractive surgery (including BOTOX injection)
- Abnormality of the cornea, lens, or central retina
- Down syndrome or cerebral palsy
- Severe developmental delay which would interfere with treatment or evaluation (in the opinion of the investigator). Subjects with mild speech delays or reading and/or learning disabilities are not excluded.
- Any disease known to affect accommodation, vergence, and ocular motility such as multiple sclerosis, Graves orbitopathy, dysautonomia, myasthenia gravis, or current use of atropine for amblyopia
- Anti-seizure medications [e.g., carbamazepine (Tegretol, Carbatrol, Epitol, or Equetro), diazepam (Valium or Diastat), clobazam (Frisium or Onfri), clonazepam (Klonopin), lorazepam (Ativan), ethosuximide (Zarontin), felbamate (Felbatol), lacosamide (VIMPAT), gabapentin (Neurontin), oxcarbazepine (Oxtellar XR or Trileptal), phenobarbital, phenytoin (Dilantin or Phenytek), pregabalin (Lyrica), tiagabine (Gabitril), topiramate (Topamax), valproate (Depakote), or zonisamide (Zonegran), vigabatrin (Sabril)]
Sites / Locations
- University of Alabama at Birmingham
- Midwestern University Eye Institute
- Arkansas Childrens
- University Eye Center at Ketchum Health
- Marshall B. Ketchum University
- Loma Linda University Health Care, Dept. of Ophthalmology
- Saddleback Eye Medical Associates
- Stanford University
- Western University College of Optometry
- University of California San Francisco Department of Ophthalmology
- Nova Southeastern University College of Optometry, The Eye Institute
- University of Florida Shands Hospital
- Nemours Children's Clinic
- The Emory Eye Center
- St Luke's Hospital
- The Eye Specialists Center, LLC
- Ann & Robert H. Lurie Children's Hospital of Chicago
- Illinois College of Optometry
- Midwestern U Chicago College of Optometry
- Pediatric Eye Associates
- Indiana University School Of Optometry
- Riley Hospital for Children
- The Eye Specialist Center, LLC
- Wolfe Eye Clinic
- University of Kentucky Department of Neurology
- Greater Baltimore Medical Center
- Wilmer Eye Institute
- Tufts Medical Center
- Boston Medical Center
- Helen DeVos Children's Hospital Pediatric Ophthalmology
- Pediatric Ophthalmology, P.C.
- Children's Eye Care PC
- University of Minnesota
- Mayo Clinic Department of Ophthalmology
- Children's Mercy Hospitals and Clinics
- U of MO St. Louis College of Optometry
- University of Nebraska Medical Center
- Concord Ophthalmologic Associates
- State University of New York, College of Optometry
- Duke University Eye Center
- Akron Children's Hospital
- Cincinnati Children's Hospital
- The Ohio State University College of Optometry
- Eye Care Associates, Inc.
- Dean A. McGee Eye Institute, University of Oklahoma
- Pacific University College of Optometry
- Casey Eye Institute
- Conestoga Eye
- Salus University/Pennsylvania College of Optometry
- UPMC Children's Eye Center of Children's Hospital of Pittsburgh
- Medical University of South Carolina, Storm Eye Institute
- Pediatric Eye Specialists
- Southern College of Optometry
- Texas Children's Hospital - Dept. Of Ophthalmology
- University of Houston College of Optometry
- Texas Tech University Health Science Center
- Houston Eye Associates
- Virginia Pediatric Eye Center
- Gundersen Health System
- Alberta Children's Hospital
- CHU - Sainte-Justine
Arms of the Study
Arm 1
Arm 2
Experimental
Active Comparator
Overminus Treatment
Non-overminus Treatment
spectacles with full cycloplegic refraction plus 2.50 D overminus added to the sphere
spectacles with full cycloplegic refraction without overminus