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Interventions for Convergence Insufficiency in Concussed Children

Interventions for Convergence Insufficiency in Concussed Children (ICONICC)

Status
UNKNOWN
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03908112
Acronym
ICONICC
Enrollment
264
Registered
2019-04-09
Start date
2021-04-01
Completion date
2025-03-31
Last updated
2020-10-23

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Concussion, Convergence Insufficiency

Keywords

convergence insufficiency, concussion, vision therapy, vision rehabilitation

Brief summary

The ICONICC Study is a randomized controlled clinical trial designed to compare the proportion of successful treatment outcomes between children assigned to standard concussion care only, standard concussion care plus simple convergence procedures, or standard concussion care plus office-based vergence/accommodative therapy in children aged 11 to 17 years with symptomatic post-concussion syndrome. Children with post-concussion syndrome (4-12 weeks post-concussion injury) and symptomatic CI will be randomized to a 12-week treatment program of either standard concussion care (SC), SC plus simple convergence procedures (SC+), or SC plus office-based vergence/accommodative therapy SC+OBVAT (1:1:1 ratio). The study will also compare the effect of treatment on clinical measures of both accommodation and vergence, symptom level/burden, health-related quality of life, clinical measures of saccadic eye movement, and objective eye movement measurements of disparity vergence, saccadic function, and accommodative function. The attainment of objective eye movement measures provides an opportunity to understand the underlying neurophysiology of the vergence and accommodative systems. Objective eye movement recordings are powerful because of the rich foundation from primate single-cell recordings that show a direct correlation with vergence and accommodative parameters in the supraoculomotor area of midbrain2, 3 and the oculomotor vermis of the cerebellum.4, 5 Thus, a combined approach of acquiring both clinical vision function measures and objective eye movement recordings in children with PCS-CI may lead to better characterization of the oculomotor phenotype with subsequent improved and personalized therapeutic interventions.

Detailed description

Objectives: A group of 264 diverse children, ages 11 to 17 years, with post-concussion syndrome (4-12 weeks post-concussion injury) and symptomatic CI will be enrolled from 6 sites from across the United States, will be randomized to 12 weeks of: 1) standard care (SC), 2) SC plus simple convergence exercises (SC+), and 3) SC plus office-based vergence/ accommodative therapy (SC+OBVAT). Primary Objective: To compare the effectiveness of SC, SC+, SC plus office-based vergence/accommodative therapy for improving a composite outcome measure of clinical findings (near point of convergence and positive fusional vergence at near) in children 11-17 years of age with concussion-related CI after 12 weeks of treatment. * Secondary outcome measures * Objective measures of disparity vergence, accommodation, saccades, and smooth pursuit * Quality of life measures * Convergence Insufficiency Symptom Survey Concussion Version (CISS-CON) * PedsQL Version 4 For participants in any treatment group who not successful based on the composite score described above, additional/different treatment will be offered as an option after the primary outcome examination

Interventions

BEHAVIORALStandard Community Concussion Care (SC)

temporary rest, gradual increase in activity, and return to school and sports. In some cases vestibular an balance therapy are necessary, aerobic exercises, medication, counseling.

BEHAVIORALSC plus Simple Convergence Exercises (SC+)

In addition to standard community care in this intervention the participants must perform convergence therapy every day at home

BEHAVIORALSC plus Office-based Vergence/Accommodative Therapy (SC+OBVAT)

In addition to standard community care in this intervention the participants must come to the office once a week for a 1-hour therapy session with a therapist. Office-based vergence/accommodative therapy is performed for 12 weeks with home reinforcement.

Sponsors

Ohio State University
CollaboratorOTHER
University of Alabama at Birmingham
CollaboratorOTHER
Marshall B. Ketchum University
CollaboratorUNKNOWN
Stanford University
CollaboratorOTHER
Children's Hospital Medical Center, Cincinnati
CollaboratorOTHER
Children's Hospital of Philadelphia
CollaboratorOTHER
Boston Children's Hospital
CollaboratorOTHER
New Jersey Institute of Technology
CollaboratorOTHER
Mitchell Scheiman
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)

Masking description

Participants will be masked to the treatment assignment and at follow-up examinations the examiners will be masked to the treatment group assignment. Investigators providing the therapy will be unmasked.

Intervention model description

To compare the effectiveness of SC, SC+, SC plus office-based vergence/accommodative therapy for improving a composite outcome measure of clinical findings (near point of convergence and positive fusional vergence at near) in children 11-17 years of age with concussion-related CI after 12 weeks of treatment.

Eligibility

Sex/Gender
ALL
Age
11 Years to 17 Years
Healthy volunteers
Yes

Inclusion criteria

ICONICC will enroll children of all races and will adhere to a policy of equitability. To be eligible to participate in ICONICC, the child must meet all of the following criteria: 1. Medical diagnosis of concussion of at least 4 weeks and no longer than 12 weeks since known date of injury 2. Age 11 to 17 years 3. Gender - any 4. CI Symptom Survey (CISS) score ≥ 16 5. Exophoria at near at least 4∆ greater than at far 6. Receded near point of convergence (NPC) of greater than 6 cm break 7. Insufficient positive fusional vergence (PFV) at near (i.e., failing Sheard's criterion1 or PFV ≤15∆ base-out break) 8. Best-corrected distance visual acuity of 20/25 or better in each eye 9. Random dot stereopsis appreciation of 500 seconds of arc or better using the Randot Stereotest 10. Willing to wear refractive correction for any of the following uncorrected refractive errors based on a cycloplegic refraction performed at the eligibility examination. (Correction must be worn for at least 2 weeks): * Myopia \> -0.75 D spherical equivalent in either eye * Hyperopia \> 2.00 D spherical equivalent in either eye * Anisometropia \> 0.75D spherical equivalent or ≥ 1.50 D in any meridian * Astigmatism \> 1.00 D in either eye 11. Willing to discontinue BI prism or a plus add at near for duration of study (must discontinue at least 2 weeks before eligibility examination) 12. Parent and child understand protocol and are willing to accept randomization 13. Normal pupillary responses

Exclusion criteria

1. Any strabismus at distance 2. Constant strabismus at near 3. Limitation on versions/ductions due to restrictive or paretic strabismus 4. Esophoria of ≥ 2∆ at distance 5. Vertical heterophoria ≥ 2∆ at distance or near 6. ≥ 2 line interocular difference in best-corrected visual acuity 7. Manifest or latent nystagmus 8. History of surgery or botulinum toxin for strabismus or any type of refractive surgery 9. Previous diagnosis of CI by an eye care professional before concussion 10. Diseases known to affect accommodation, vergence, or ocular motility such as multiple sclerosis, Graves orbitopathy, myasthenia gravis, diabetes mellitus, Parkinson's disease 11. Inability to comprehend and/or perform any study-related, clinical vision function test 12. Household member enrolled in present ICONICC study or treated within the past 6 months with any form of office-based vergence/accommodative therapy or home-based vergence therapy (e.g., computerized vergence therapy) 13. Household member is an eye care professional, ophthalmic technician, ophthalmology or optometry resident or fellow, or optometry student

Design outcomes

Primary

MeasureTime frameDescription
Composite of Measure of the Near Point of Convergence (NPC) and Positive Fusional Vergence at Near (PFV)12 weeksTo evaluate successful treatment of CI, we will use a composite outcome classification of the 2 clinical outcome measures of NPC and PFV from baseline to the primary outcome examination. A participant will be defined as successfully treated if both criteria are met: 1) normal NPC (i.e., less than 6 cm) and 2) normal PFV (i.e., greater than 15 prism diopters base-out and passing Sheard's criterion

Secondary

MeasureTime frameDescription
Time to peak velocity for 4° symmetrical convergence steps12 WeeksThe ISCAN RK-826PCI binocular tracking system (Burlington, MA) will be used to objectively record horizontal vergence eye movements. Five parameters will be measured with this instrument and a secondary outcome measures will be the change in time to peak velocity for 4° symmetrical convergence steps
Latency for 4° symmetrical convergence steps12 weeksThe ISCAN RK-826PCI binocular tracking system (Burlington, MA) will be used used to objectively record horizontal vergence eye movements. Five parameters will be measured with this instrument and a secondary outcome measures will be the change in latency for 4° symmetrical convergence steps
Response Amplitude for 4° symmetrical convergence steps12 weeksThe ISCAN RK-826PCI binocular tracking system (Burlington, MA) will be used to objectively record horizontal vergence eye movements. Five parameters will be measured with this instrument and a secondary outcome measures will be the change in response amplitude for 4° symmetrical convergence steps
Peak velocity for 4° symmetrical convergence steps12 weeksThe ISCAN RK-826PCI binocular tracking system (Burlington, MA) will be used used to objectively record horizontal vergence eye movements. Peak velocity will be measured with this instrument and a secondary outcome measures will be the change in peak velocity for 4° symmetrical convergence steps
Post-concussion Symptom Inventory (PCSI)12 weeksPCSI is a 26-item validated symptom inventory for children with concussion that identifies physical, cognitive, emotional and sleep factors following injury and is useful in capturing and tracking post-injury symptoms through recovery. The change in this score will be used as a secondary outcome measure.
PedsQL (Pediatric Quality of Life Inventory)12 WeeksPedsQL (Pediatric Quality of Life Inventory) measures health-related quality of life (HRQOL) in children and adolescents. The change in this score will be used as a secondary outcome measure.
Convergence Insufficiency Symptom Survey - Concussion Version (CISS-CON)12 weeksThe change in the score on this survey will be a secondary outcome assessing symptoms

Countries

United States

Contacts

Primary ContactMitchell Scheiman, OD, PhD
mscheiman@salus.edu215-780-1427
Backup ContactWendy Woodward
wwoodward@salus.edu215-780-1429

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026