A Prospective Observational Study of Adult Strabismus

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT02510040

Acronym

SAS1

Enrollment

217

Registered

2015-07-28

Start date

2015-08-17

Completion date

2019-01-31

Last updated

2023-07-06

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

Conditions

Convergence Insufficiency, Divergence Insufficiency, Hypertropia

Keywords

Convergence Insufficiency, Divergence Insufficiency, Small-angle Hypertropia, Strabismus

Brief summary

The purpose of this study is to describe clinical characteristics, treatments, and one-year outcomes of adults with convergence insufficiency, divergence insufficiency, or small angle hypertropia.

Detailed description

The purpose of this study is to describe clinical characteristics, treatments, and one-year outcomes of adults with convergence insufficiency, divergence insufficiency, or small angle hypertropia. Treatment comparisons within the studied conditions will also be done to help develop future studies.

Interventions

DEVICEPrism

Ground-in or Fresnel prism

OTHEROrthoptic Exercises

Orthoptic exercises- fusion, convergence, divergence, and others, including computer-based therapy

PROCEDUREEye Muscle Surgery

* Bilateral medial rectus muscle resection surgery * Single medial rectus muscle resection surgery * Recess lateral rectus muscle resection medial rectus muscle surgery * Bilateral lateral rectus muscle recession surgery * Single lateral rectus muscle recession surgery * Bilateral lateral rectus muscle resection surgery * Single lateral rectus muscle resection surgery * Recess medial rectus muscle resection lateral rectus muscle surgery * Bilateral medial rectus muscle recession surgery * Single medial rectus muscle recession surgery * Vertical rectus muscle recession surgery * Vertical rectus muscle mini-tenotomy (snip) surgery

PROCEDUREBotox Injection

Botulinum toxin injection

Study design

Observational model

COHORT

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

Eligibility Criteria for Convergence Insufficiency (CI) Group: The following inclusion criteria must be met for the subject to be enrolled into the study: * Adults ≥18 years of age (adult onset of CI not required) * No strabismus surgery within the past 10 years * CI Symptom Survey score ≥21 points * Near exodeviation of ≥4∆ and at least 4∆ larger than at distance by PACT * Distance exodeviation ≤15∆ by PACT * Vertical deviation ≤2∆ at distance and near by PACT * No constant exotropia at distance or near * Reduced positive fusional vergence (PFV) at near (\<20∆ or fails Sheard's criterion that the PFV measures less than twice the magnitude of the near phoria) * Near point of convergence (NPC) of ≥6 cm break * Visual acuity 20/50 or better in both eyes by ETDRS or Snellen * No paralytic strabismus (e.g., 3rd, 4th, or 6th cranial nerve palsies, skew deviation, Duane syndrome) * No restrictive strabismus (e.g., blowout fracture, thyroid eye disease, post scleral buckle, Brown syndrome) * No monocular diplopia * No paretic strabismus, thyroid eye disease, myasthenia gravis, chronic progressive external ophthalmoplegia, or eye movement abnormalities associated with known neurological disease. Patients with Parkinson's disease can be enrolled if non-paretic deviation. * No inferior or superior oblique overaction defined as 2+ or greater * Ability to fuse with prism in space (see section 2.4.1) * Ability to understand and complete a survey * Investigator is initiating treatment with prism, orthoptic exercises, botulinum toxin injection or surgery * If initiating treatment with botulinum toxin or surgery, planned injection or surgery to be within 60 days of enrollment * Single treatment modality is planned (e.g., no combined prism and orthoptic exercises) * Treatment to be initiated has not been used within the past one year Eligibility Criteria for Divergence Insufficiency (DI) Group: The following inclusion criteria must be met for the subject to be enrolled into the study: * Adults ≥18 years of age * Adult-onset DI (at ≥18 years of age) * No prior strabismus surgery * Symptoms of diplopia at distance with a frequency of sometimes or worse in primary position (in current glasses if wearing glasses) * Distance esodeviation of 2∆ to 30∆ and at least 50% larger than at near by PACT * No more than 5∆ difference between right and left gaze by PACT * No more than 10∆ difference between the primary position at distance and either upgaze or downgaze ≤10∆ by PACT * Any coexisting vertical deviation must be less than distance esodeviation and ≤10∆ by PACT * Visual acuity 20/50 or better in both eyes by ETDRS or Snellen * No paralytic strabismus (e.g., 3rd, 4th, or 6th cranial nerve palsies, skew deviation, Duane syndrome) * No restrictive strabismus (e.g., blowout fracture, thyroid eye disease, post scleral buckle, Brown syndrome) * No monocular diplopia * No paretic strabismus, thyroid eye disease, myasthenia gravis, chronic progressive external ophthalmoplegia, or eye movement abnormalities associated with known neurological disease. Patients with Parkinson's disease can be enrolled if non-paretic deviation * No inferior or superior oblique overaction defined as 2+ or greater * Ability to fuse with prism in space (see section 2.4.2) * Ability to understand and complete a survey * Investigator is initiating treatment with prism, orthoptic exercises, botulinum toxin injection or surgery * If initiating treatment with botulinum toxin or surgery, planned injection or surgery to be within 60 days of enrollment * Single treatment modality planned (e.g., no combined prism and orthoptic exercises) * Treatment to be initiated has not been used within the past one year Eligibility Criteria for Small-angle Hypertropia (HT) Group: The following inclusion criteria must be met for the subject to be enrolled into the study: * Adults ≥18 years of age * Adult-onset HT (at ≥18 years of age) * No prior strabismus surgery * Symptoms of diplopia at distance or near with a frequency of sometimes or worse in primary or reading position (in current glasses if wearing glasses) * Vertical deviation ≥1∆ to ≤10∆ at distance and near by PACT * No more than 4∆ difference from the primary in any gaze position by PACT * Any coexisting esodeviation must be less than the vertical deviation * Any coexisting exodeviation ≤10∆ by PACT * No convergence insufficiency as defined in section 2.2.1 * Visual acuity 20/50 or better in both eyes by ETDRS or Snellen * No paralytic strabismus (e.g., 3rd, 4th, or 6th cranial nerve palsies, skew deviation, Duane syndrome) * No restrictive strabismus (e.g., blowout fracture, thyroid eye disease, post scleral buckle, Brown syndrome) * No monocular diplopia * No paretic strabismus, thyroid eye disease, myasthenia gravis, chronic progressive external ophthalmoplegia, or eye movement abnormalities associated with known neurological disease. Patients with Parkinson's disease can be enrolled if non-paretic deviation. * No inferior or superior oblique overaction defined as 2+ or greater * Ability to fuse with prism in space (see section 2.4.3) * Ability to understand and complete a survey * Investigator is initiating treatment with prism, orthoptic exercises, botulinum toxin injection or surgery * If initiating treatment with botulinum toxin or surgery, planned injection or surgery to be within 60 days of enrollment * Single treatment modality planned (e.g., no combined prism and orthoptic exercises) * Treatment to be initiated has not been used within the past one year

Exclusion criteria

for Convergence Insufficiency (CI) Group: The following criteria exclude a subject from enrollment into the study: * Strabismus surgery within the past 10 years * CI Symptom Survey score ≥21 points * Near exodeviation of ≤4∆ and at least 4∆ larger than at distance by PACT * Distance exodeviation ≥15∆ by PACT * Vertical deviation ≥2∆ at distance and near by PACT * Constant exotropia at distance or near * Near point of convergence (NPC) of ≤6 cm break * Visual acuity worse than 20/50 either eye by ETDRS or Snellen * Paralytic strabismus (e.g., 3rd, 4th, or 6th cranial nerve palsies, skew deviation, Duane syndrome) * Restrictive strabismus (e.g., blowout fracture, thyroid eye disease, post scleral buckle, Brown syndrome) * Monocular diplopia * Paretic strabismus, thyroid eye disease, myasthenia gravis, chronic progressive external ophthalmoplegia, or eye movement abnormalities associated with known neurological disease. Patients with Parkinson's disease can be enrolled if non-paretic deviation. * Inferior or superior oblique overaction defined as 2+ or greater * Inability to fuse with prism in space (see section 2.4.1) * Inability to understand and complete a survey * Treatment to be initiated has already been used within the past one year

Design outcomes

Primary

Measure	Time frame	Description
Number of Participants With Symptom Success at 10 Weeks	10 weeks after enrollment	In the convergence insufficiency group, the primary outcome will be symptom success at the 10-week and 12-month visit, defined as improvement of CI Symptom Survey (CISS) score of at least 9 points and an outcome score of \<21 points. In the divergence insufficiency group, the primary outcome will be symptom success at the 10-week and 12-month visit, defined as diplopia rarely or never in primary position at distance on the diplopia questionnaire. In the small-angle hypertropia group, the primary outcome will be symptom success at the 10-week and 12-month visit, defined as diplopia rarely or never both in primary position at distance and in reading position on the diplopia questionnaire.
Number of Participants With Symptom Success at 12 Months	12 months after enrollment	In the convergence insufficiency group, the primary outcome will be symptom success at the 10-week and 12-month visit, defined as improvement of CI Symptom Survey (CISS) score of at least 9 points and an outcome score of \<21 points. In the divergence insufficiency group, the primary outcome will be symptom success at the 10-week and 12-month visit, defined as diplopia rarely or never in primary position at distance on the diplopia questionnaire. In the small-angle hypertropia group, the primary outcome will be symptom success at the 10-week and 12-month visit, defined as diplopia rarely or never both in primary position at distance and in reading position on the diplopia questionnaire.

Secondary

Measure	Time frame	Description
Adult Strabismus 20 Questionnaire Score (DI)	12 months after enrollment	Adult Strabismus Quality of Life Questionnaire (AS-20) For AS-20, scores are reported for the following subscales. A total score will not be reported. 1. Self-perception score 2. Interaction score 3. Reading function score 4. General function score Values for each subscale range from 0 to 100. 0 indicates poor quality of life (the patient reported always for all questions) and 100 represents good quality or life (patient reported never for all questions)
Mean of Near Point of Convergence in Convergence Insufficiency Group	12 months after enrollment	Near point of convergence (convergence insufficiency group only).
Adult Strabismus 20 Questionnaire Score (CI)	12 months after enrollment	Adult Strabismus Quality of Life Questionnaire (AS-20) For AS-20, scores are reported for the following subscales. A total score will not be reported. Self-perception score Interaction score Reading function score General function score Values for each subscale range from 0 to 100. 0 indicates poor quality of life (the patient reported always for all questions) and 100 represents good quality or life (patient reported never for all questions)
Mean Convergence Insufficiency Symptom Survey Score	12 months after enrollment	Mean Convergence Insufficiency Symptom Survey Score (convergence insufficiency group only) For CISS, the range is from 0 (having no symptoms of CI) to 60 (always showing all symptoms of CI).
Mean Positive Fusional Vergence in Convergence Insufficiency Group	12 months after enrollment	Positive fusional vergence (convergence insufficiency group only).

Countries

United States

Participant flow

Participants by arm

Arm	Count
Convergence Insufficiency Eligible adults with convergence insufficiency can be treated with prism, orthoptic exercises, eye muscle surgery, or botox injection, per the investigator's usual clinical practice. Prism: Ground-in or Fresnel prism Orthoptic Exercises: Orthoptic exercises- fusion, convergence, divergence, and others, including computer-based therapy Eye Muscle Surgery: • Bilateral medial rectus muscle resection surgery * Single medial rectus muscle resection surgery * Recess lateral rectus muscle resection medial rectus muscle surgery * Bilateral lateral rectus muscle recession surgery * Single lateral rectus muscle recession surgery * Bilateral lateral rectus muscle resection surgery * Single lateral rectus muscle resection surgery * Recess medial rectus muscle resection lateral rectus muscle surgery * Bilateral medial rectus muscle recession surgery * Single medial rectus muscle recession surgery * Vertical rectus muscle recession surgery * Vertical rectus muscle mini-tenotomy (snip) surgery Botox Injection: Botulinum toxin injection	63
Divergence Insufficiency Eligible adults with divergence insufficiency can be treated with prism, orthoptic exercises, eye muscle surgery, or botox injection, per the investigator's usual clinical practice. Prism: Ground-in or Fresnel prism Orthoptic Exercises: Orthoptic exercises- fusion, convergence, divergence, and others, including computer-based therapy Eye Muscle Surgery: • Bilateral medial rectus muscle resection surgery * Single medial rectus muscle resection surgery * Recess lateral rectus muscle resection medial rectus muscle surgery * Bilateral lateral rectus muscle recession surgery * Single lateral rectus muscle recession surgery * Bilateral lateral rectus muscle resection surgery * Single lateral rectus muscle resection surgery * Recess medial rectus muscle resection lateral rectus muscle surgery * Bilateral medial rectus muscle recession surgery * Single medial rectus muscle recession surgery * Vertical rectus muscle recession surgery * Vertical rectus muscle mini-tenotomy (snip) surgery Botox Injection: Botulinum toxin injection	111
Small-angle Hypertropia Eligible adults with small-angle hypertropia can be treated with prism, orthoptic exercises, eye muscle surgery, or botox injection, per the investigator's usual clinical practice. Prism: Ground-in or Fresnel prism Orthoptic Exercises: Orthoptic exercises- fusion, convergence, divergence, and others, including computer-based therapy Eye Muscle Surgery: • Bilateral medial rectus muscle resection surgery * Single medial rectus muscle resection surgery * Recess lateral rectus muscle resection medial rectus muscle surgery * Bilateral lateral rectus muscle recession surgery * Single lateral rectus muscle recession surgery * Bilateral lateral rectus muscle resection surgery * Single lateral rectus muscle resection surgery * Recess medial rectus muscle resection lateral rectus muscle surgery * Bilateral medial rectus muscle recession surgery * Single medial rectus muscle recession surgery * Vertical rectus muscle recession surgery * Vertical rectus muscle mini-tenotomy (snip) surgery Botox Injection: Botulinum toxin injection	21
Total	195

Withdrawals & dropouts

Period	Reason	FG000	FG001	FG002
Overall Study	Deemed no longer eligible	18	3	1

Baseline characteristics

Characteristic	Convergence Insufficiency	Divergence Insufficiency	Small-angle Hypertropia	Total
Age, Continuous	38.2 years	71.2 years	71.5 years	65.3 years
Race/Ethnicity, Customized Non-white	31 Participants	4 Participants	2 Participants	37 Participants
Race/Ethnicity, Customized White	32 Participants	107 Participants	19 Participants	158 Participants
Sex: Female, Male Female	48 Participants	74 Participants	10 Participants	132 Participants
Sex: Female, Male Male	15 Participants	37 Participants	11 Participants	63 Participants

Adverse events

Event type	EG000 affected / at risk	EG001 affected / at risk	EG002 affected / at risk
deaths Total, all-cause mortality	0 / 0	0 / 0	0 / 0
other Total, other adverse events	0 / 0	0 / 0	0 / 0
serious Total, serious adverse events	0 / 0	0 / 0	0 / 0

Outcome results

Primary

Number of Participants With Symptom Success at 10 Weeks

In the convergence insufficiency group, the primary outcome will be symptom success at the 10-week and 12-month visit, defined as improvement of CI Symptom Survey (CISS) score of at least 9 points and an outcome score of \<21 points. In the divergence insufficiency group, the primary outcome will be symptom success at the 10-week and 12-month visit, defined as diplopia rarely or never in primary position at distance on the diplopia questionnaire. In the small-angle hypertropia group, the primary outcome will be symptom success at the 10-week and 12-month visit, defined as diplopia rarely or never both in primary position at distance and in reading position on the diplopia questionnaire.

Time frame: 10 weeks after enrollment

Arm	Measure	Value (COUNT_OF_PARTICIPANTS)
Convergence Insufficiency	Number of Participants With Symptom Success at 10 Weeks	25 Participants
Divergence Insufficiency	Number of Participants With Symptom Success at 10 Weeks	91 Participants
Small-angle Hypertropia	Number of Participants With Symptom Success at 10 Weeks	12 Participants

Primary