The Effects of Fresnel Prism Glasses on Visual Perception, Balance, Gait and Functional Independence in Post-Stroke Patients

NCT07308054 | Not Yet Recruiting DMC

• 1 other identifier: UBAS/ERB/FpRS/25/035
• Study Type: interventional
• Target: 50
• Locations: 0 countries
• Sites: N/A

Brief Summary

This randomized controlled trial aims to evaluate the effects of Fresnel prism glasses on visual perception, balance, gait, and functional independence in post-stroke patients. Stroke survivors, particularly those with right hemisphere involvement, often experience visuospatial deficits such as unilateral spatial neglect, leading to impaired balance, abnormal gait, and reduced functional independence. Fresnel prism glasses offer a low-cost, non-invasive intervention that may improve visuospatial alignment and postural control by modifying visual input. Adult post-stroke patients will be randomly allocated into an intervention group receiving Fresnel prism glasses alongside conventional physical therapy, and a control group receiving conventional therapy alone. Outcome measures will include the Motor-Free Visual Perception Test, Berg Balance Scale, Functional Independence Measure, and JAKC Observational Gait Analysis. Assessments will be conducted at baseline, post-intervention, and follow-up. The study is expected to provide evidence on whether Fresnel prism glasses can serve as an effective adjunct to conventional rehabilitation for improving mobility, balance, and functional outcomes in stroke survivors.

Conditions

Stroke

Keywords

Visual Perception; Functional Independence; Fresnel Prism Glasses; Gait; Balance

Outcome Measures

Primary Outcomes (4)

• Motor-Free Visual Perception Test

  The Motor-Free Visual Perception Test (MVPT) is a standardized assessment tool consisting of 36 items that evaluate multiple domains of visual perception, including figure-ground discrimination, visual discrimination, visual memory, visual closure, and spatial relationships. It is designed to assess visual field deficits and overall visual perceptual function in patients who have experienced brain injuries or strokes. In this study, we measured participants' response behaviors to identify the extent of unilateral neglect by recording their responses to both the left and right sides of the body, regardless of accuracy. Correct responses are scored as raw points, while the total time taken to complete the assessment is recorded as the visual perceptual processing time. The maximum score achievable is 36 points. The MVPT demonstrates high reliability, with a test-retest intraclass correlation coefficient (ICC) of 0.92 (95% CI: 0.84-0.96). In this trial, the MVPT will be utilized.

  Baseline, before intervention, 8 weeks post intervention

• Berg Balance Scale

  The Functional Independence Measure (FIM) is a key tool used to assess the level of disability in patients undergoing rehabilitation. It evaluates 18 different activities of daily living on a scale from 1 to 7, where 1 means the person is fully dependent and 7 means they can do everything independently without any assistance. The highest possible score is 126, which signifies complete functional independence, while the lowest score of 18 indicates total dependence. The activities are divided into two main categories: 13 motor skills (like personal care, sphincter control, mobility, and locomotion) and five cognitive skills (which include communication and social cognition)

  baseline, before interventio, 8 weeks post intervention

• Functional Independence Measure

  Independence Measure (FIM) is a key tool used to assess the level of disability in patients undergoing rehabilitation. It evaluates 18 different activities of daily living on a scale from 1 to 7, where 1 means the person is fully dependent and 7 means they can do everything independently without any assistance(23). The highest possible score is 126, which signifies complete functional independence, while the lowest score of 18 indicates total dependence. The activities are divided into two main categories: 13 motor skills (like personal care, sphincter control, mobility, and locomotion) and five cognitive skills (which include communication and social cognition)

  baseline, before intervention, 8 weeks post intervention

• JAKC's Observational Gait Analysis

  The JAKC Observational Gait Analysis (Joint Angle Kinematic Coordination) is a wellstructured clinical tool designed to evaluate gait patterns, especially in individuals dealing with neurological or musculoskeletal issues like stroke. It zeroes in on the coordination and quality of movement in key joints-namely the hip, knee, ankle, and trunk-throughout various stages of the gait cycle. By closely observing joint angles, timing, and how limbs work together, therapists can spot unusual movement patterns and compensatory behaviors. The JAKC scale aids in clinical decision-making by pinpointing specific gait deviations, which helps in crafting targeted interventions and tracking progress over time. It's a practical, non-invasive approach that's widely embraced in rehabilitation environments

  Baseline, before intervention, 8 week post intervention

Study Arms (2)

Arm/group

EXPERIMENTAL

Participants allocated to the experimental group will receive Fresnel prism glasses (15 prism diopters) in addition to conventional physiotherapy. The Fresnel prism lenses will be affixed to the participant's spectacles to induce visuospatial realignment during therapeutic activities. Participants will wear the prism glasses during supervised rehabilitation sessions focused on balance training, gait training, and functional mobility tasks. Conventional physiotherapy will include postural control exercises, weight-shifting activities, gait re-education, and task-oriented functional training. The intervention will be administered for 4 weeks, with sessions conducted 5 days per week, under the supervision of a qualified physiotherapist.

Device: Fresnel Prism Glasse; Behavioral: Convetional physical therapy

Arm/Group

ACTIVE COMPARATOR

Participants allocated to the control group will receive conventional physiotherapy alone, without the use of Fresnel prism glasses. The rehabilitation program will follow standard neurorehabilitation protocols and will include balance exercises, gait training, strengthening, postural alignment exercises, and functional mobility tasks. Therapy will be provided with the same frequency and duration as the experimental group (5 sessions per week for 4 weeks) to ensure comparability between groups.

Behavioral: Convetional physical therapy

Interventions

Fresnel Prism Glasse DEVICE

Fresnel prism glasses consist of lightweight, flexible, press-on plastic prism lenses with a power of 15 prism diopters, affixed to the inner surface of standard spectacle lenses. The prisms are designed to shift the visual field horizontally to promote visuospatial realignment and improve sensory integration during functional activities. Participants assigned to the experimental group will wear Fresnel prism glasses during supervised physiotherapy sessions. The intervention will be administered alongside conventional physiotherapy, including balance training, gait training, postural control exercises, and functional mobility tasks. The prism glasses will be worn throughout the therapy session to facilitate visual feedback and encourage symmetrical weight-bearing and improved postural alignment. The intervention will be delivered for a duration of 4 weeks, with sessions conducted 5 days per week. Each session will last approximately 30-45 minutes and will be supervised by a qualified

Arm/group

Convetional physical therapy BEHAVIORAL

Conventional physiotherapy will be provided to all participants in both groups according to standard neurorehabilitation protocols. The program will include balance exercises, gait training, strengthening exercises, postural alignment activities, weight-shifting exercises, and task-oriented functional training. Participants in the control group will receive conventional physiotherapy alone, without Fresnel prism glasses, for the same duration and frequency as the experimental group.

Arm/Group; Arm/group

Eligibility Criteria

• Age: 55 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

Sponsors & Collaborators

• Lahore University of Biological and Applied Sciences: lead

Related Publications (1)

• Ha SY, Sung YH. Effects of Fresnel prism glasses on balance and gait in stroke patients with hemiplegia: A randomized controlled trial pilot study. Technol Health Care. 2020;28(6):625-633. doi: 10.3233/THC-191973.

  PMID: 32280072 RESULT

MeSH Terms

Conditions

Stroke

Condition Hierarchy (Ancestors)

Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases

Central Study Contacts

Muhammad Asad Azam, Master of physical therapy

CONTACT

+923217267679; asadazam10000@gmail.com

Salwa Atta, Supervisor

CONTACT

+923084579229; salwa.atta@ubas.edu.pk

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: After recruitment of participants into the study, they will be allocated to their respective group utilizing the online randomization tool.

Study Record Dates

• First Submitted: December 15, 2025
• First Posted: December 29, 2025
• Study Start: December 13, 2025
• Primary Completion (Estimated): May 26, 2026
• Study Completion (Estimated): May 26, 2026
• Last Updated: December 29, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share