NCT07531667

Fresnel Prism in Low Vision Patients With Homonymous Hemianopia Defect in Cipto Mangunkusumo Hospital

Use of Fresnel Prism in Low Vision Patients With Homonymous Hemianopia Defect in Cipto Mangunkusumo Hospital

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 25 (actual)
• Sponsor: Indonesia University · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

Background: Homonymous hemianopia is a visual field defect that causes functional disabilities, such as decreased self-confidence, limited mobility, and increased risk of falls. Studies related to the effectiveness and comfort of Fresnel prisms, especially in the Indonesian population are limited. Objective: To evaluate the effectiveness and comfort level of Fresnel prisms in expanding visual field in an Indonesian patient population with homonymous hemianopia.

Detailed description

: Fresnel prisms with a power of 40∆ were fitted to the patient's spectacles for two weeks. Visual field parameters were analysed using the Humphrey Field Analyzer with the SITA 24-2 algorithm, while the Pelli-Robson and ETDRS charts were used to assess contrast sensitivity and visual acuity, respectively. After visual assessment, comfort was quantitatively assessed using a comfort scale.

Conditions

• Fresnel Prism

Interventions

Type	Name	Description
DEVICE	Fresnel prism	The Fresnel prism chosen was of 40∆ power (the largest size available) with the aim of the largest visual field expansion, which was 20 degrees that the patient felt during environmental orientation and mobilisation. Fresnel prism fitting was performed using the patient's spectacles (if wearing spectacles) or plano glasses provided by the researcher. The patient was given object movement stimulation to identify the visual field boundary and the Fresnel prism was placed 2 mm away from the healthy visual field area. The Fresnel prism was placed on the inner side of the lens. Vertical correction was performed in homonymous hemianopia depending on the visual field defect. The patient was then asked to practice scanning before being asked to wear the Fresnel prism for 5.5 hours daily for two weeks. Patients were given a wear sheet to evaluate the duration of wear in a day.

Timeline

• Start date: 2022-05-01
• Primary completion: 2022-07-01
• Completion: 2022-08-01
• First posted: 2026-04-15
• Last updated: 2026-04-15

Locations

1 site across 1 country: Indonesia