Normal isopter position in the peripheral visual field in goldmann kinetic perimetry

Area of Science:

• Ophthalmology
• Visual Science

Background:

• Peripheral visual field assessment is crucial for detecting early signs of disease in young patients.
• Kinetic perimetry offers higher sensitivity for peripheral visual field abnormalities compared to static perimetry due to the steeper 'hill of vision' in the periphery.

Purpose of the Study:

• To determine the normal position of four frequently used isopters (V4e, III4e, I4e, I3e) in the peripheral visual field.
• To provide a tool for easily identifying mild peripheral visual field constrictions using kinetic perimetry.

Main Methods:

• Intraindividual sensitivity variations of isopters were assessed in 3 normal subjects.
• The positions of isopters V4e, III4e, I4e, and I3e were determined in 22 subjects (19-42 years old) using a Goldmann kinetic perimeter.
• Average isopter positions and +/- 2 standard deviations were plotted for visualization.

Main Results:

• Intraindividual sensitivity variations were 0.98 degrees for V4e and 1.13 degrees for I4e.
• Normal isopter positions were visualized by plotting average positions +/- 2 standard deviations.
• Plots were created at a 1:4 scale for practical application.

Conclusions:

• Established normal positions for four key isopters used in kinetic perimetry.
• Developed a method for comparing individual kinetic visual fields to normal ranges using scaled transparencies.
• Facilitates the detection of peripheral visual field constrictions in clinical practice.