Home Vision Therapy and Prism Prescription in Presbyopic Persons With Convergence Insufficiency

NCT05311917 | Unknown

• 1 other identifier: 1400.610
• Study Type: interventional
• Target: 250
• Locations: 1 country
• Sites: 1

Brief Summary

convergence insufficiency is one of the most common binocular vision problems in which the eyes tend to have more exophoria in near than distance activities. Its prevalence is typically reported from 2.25% to 29.6% depending on the study population and its definition. Most of its symptoms include difficulty seeing at close works, headache, eye pain during study, blurred vision, diplopia, movement of words in reading, a feeling of pressure in the eye, and lack of concentration. Its signs include increasing near point of convergence, more exophoria at near than distance, decreased AC / A ratio, decreased positive fusional vergence. In patients with convergent insufficiency, the first valid and standard questionnaire to assess the frequency and type of symptoms used before and after convergence insufficiency treatment is the convergence insufficiency symptom survey (CISS) questionnaire. Generally, vision therapy is the first choice for convergence insufficiency management and the other choice is base in prism prescription. On the other hand, due to the changes in the interaction of the accommodation and convergence systems with increasing age, It is necessary to study how these systems interact and compare their responses to the active treatment of vision therapy and inactive prescription of base in prism. In this controlled study, investigators will evaluate and compare the effect of vision therapy and base in prism prescription in patients over 40 years of age. this investigation will help to clarify which treatment is more effective. This study will have two phases. In the first phase, investigators will seek to check the reliability and validity of the Persian version of CISS questionnaire for the elderly patients. For this purpose, investigators will use the Persian version questionnaire in previous study that assessed for young adults, and the investigators will modify it and check the reliability and validity of the final Persian version for subjects with presbyopia. This modified CISS questionnaire will be investigated in the elderly participants and the appropriate cut off point to differentiate between the normal group and the group with convergence insufficiency will be determined. in the second phase one optometrist (Z.K.R) will do the preliminary examination and another optometrist (S.A) will do the interventions. After the initial examination and having the inclusion criteria, patients will be invited to participate in the study, the nature of the research will be explained to subjects and informed consent will be obtained from them. Before randomization, patients are asked to complete the CISS questionnaire and submit this questionnaire to Optometrist No. 1 (Z.K.R).According to the randomization all patients will be assigned to one of the treatment or control groups by optometrist No. 1. Vision therapy exercises, necessary trainings and prescriptions are given to all patients by Optometrist No. 2 (S.A).For the participants in the control group only near glasses will be prescribed as a conventional treatment, for the second group near glasses with base in prism according to sheard's criterion will be prescribed and in the third group, the prescription of near glasses will be given along with the complete training of the home exercises.

Conditions

Convergence Insufficiency

Keywords

vision therapy; prism prescription; convergence insufficiency

Outcome Measures

Primary Outcomes (1)

• treatment success criteria

  achieving near point of convergence below 6 cm or 4 cm reduction in its distance, positive fusional vergence according to sheard criterion or grater than 15 prism or 10 prism improvement. achieving normal limit in CISS or 10 score improvement in total score.

  2 month after intervention

Study Arms (3)

home vision therapy

EXPERIMENTAL

near glasses will be prescribed along with a complete training of the exercises and with a eye exercise form of information about how and how long to do the exercise, by optometrist No 2 (Saeid Abdi).training includes: Voluntary convergence, Bug on string, Eccentric Circles, Jumping vergence , Barrel card, chiastopic fusion, Brock string, push-up These exercises will be done 3 days a week for 20 minutes ( 10 minutes at noon and 10 minutes at night ) for 2 month. Home exercises include eight vision therapy exercises and patients will do two exercises each day at noon and two exercises at night.

Other: home vision therapy

base in prism prescription

EXPERIMENTAL

base in prism prescription using sheards criterion near prismatic glasses will be prescribed and the amount of prism will be divided between two eyes; and random and aimless eye movements, without convergence and accommodation effects will be prescribed by optometrist No. 2 (Saeid Abdi). patients should complete their checking form for eye exercises.

Other: base in prism prescription

conventional

PLACEBO COMPARATOR

new near glasses as a conventional treatment with the practice of random and aimless eye movements, without convergence and accommodation effects will be prescribed by optometrist No. 2 (Saeid Abdi). patients should complete the form of their eye training.

Other: conventional placebo

Interventions

home vision therapy OTHER

a group of vision therapy procedures in home to improve convergence insufficiency

Also known as: home eye training

home vision therapy

base in prism prescription OTHER

base in prism prescription according to sheards criterion

Also known as: prism prescription

base in prism prescription

conventional placebo OTHER

using near glasses with aimless eye training

Also known as: placebo

conventional

Eligibility Criteria

• Age: 40 Years - 60 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• CISS score more than the estimated cut off point
• Best corrected visual acuity=20/20 for near and far
• Having Convergence Insufficiency
• Near exophoria should be at least 4 prisms more than distant exophoria
• NPC more than 6 cm
• Inadequate near-positive positive fusion according to the Convergence Insufficiency Treatment Trial (CITT) study (8)
• Normal monocular accomodation amplitude according to Hofster formula

You may not qualify if:

• Any type of strabismus
• Amblyopia
• Refractive error more than 6 diopters
• Patients with history of prism prescription
• History of vision therapy from 5 years ago
• History of strabismus surgery or refractive error surgery
• History of eye trauma
• Use of any ophthalmic or general ophthalmic drugs affect ocular accommodation such as phenylephrine, anticholinergic drugs (mydriatics), carbonic anhydrase inhibitors, antihistamines, morphine and its derivatives, antidepressants amphetamine and imipramine
• More than one prism of vertical phoria
• Any mechanical limitations in the eye muscles
• Ocular muscle paralysis
• Nystagmus
• Any systemic and neurological diseases affecting binocular vision such as diabetes, myasthenia gravis, Graves', multiple sclerosis

Sponsors & Collaborators

• Shahid Beheshti University of Medical Sciences: lead

Study Sites (1)

Shahid Beheshti University of Medical Sciences

Tehran, Iran

RECRUITING

Related Publications (1)

• Abdi S, Kangari H, Rahmani S, Baghban AA, Rad ZK. Home vision therapy and prism prescription in presbyopic persons with convergence insufficiency: study protocol for a randomized controlled trial. BMC Ophthalmol. 2024 Apr 15;24(1):169. doi: 10.1186/s12886-024-03411-y.

  PMID: 38622543 DERIVED

MeSH Terms

Conditions

Ocular Motility Disorders

Interventions

Alkalies

Condition Hierarchy (Ancestors)

Central Nervous System Diseases; Nervous System Diseases; Cranial Nerve Diseases; Eye Diseases

Intervention Hierarchy (Ancestors)

Inorganic Chemicals

Central Study Contacts

Saeid Abdi, PhD student

CONTACT

0989181071851; opto.abdi@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: March 27, 2022
• First Posted: April 5, 2022
• Study Start: April 3, 2022
• Primary Completion: July 1, 2023
• Study Completion: August 1, 2023
• Last Updated: April 25, 2023

Record last verified: 2023-04

Locations

IR (1)