Standard automated perimetry (SAP) is a static computerized threshold visual field test that uses a white stimulus (Goldmann size III) on a white background 3). It is the recommended test for glaucoma management 3)4).
Visual field testing is important not only for diagnosing glaucoma but also for follow-up 1). Visual field testing methods include kinetic and static perimetry.
| Item | Static perimetry (SAP) | Kinetic perimetry |
|---|---|---|
| Stimulus presentation | Luminance changes at fixed location | Moves from invisible area |
| Early detection | Excellent | Slightly inferior |
Static perimetry is more sensitive than kinetic perimetry for detecting visual field abnormalities in early glaucoma 1). Static perimetry is recommended for glaucoma management 1). Kinetic perimetry is useful for patients who cannot undergo automated perimetry and for evaluating residual peripheral visual field in advanced stages 1)3).
The main perimeters in widespread use are the Humphrey Field Analyzer (HFA) and the Octopus perimeter 1). The HFA uses a background illumination of 31.5 asb and performs testing under photopic conditions, primarily testing cone cells. Stimuli are presented for 0.2 seconds, and a sensitivity range of 50 dB is measured.
SAP is excellent for detecting visual field abnormalities in early glaucoma and provides quantitative, highly reproducible results, making it the standard test for glaucoma management and follow-up 1)3). On the other hand, kinetic perimetry (Goldmann perimeter) is useful for evaluating residual peripheral visual field in end-stage glaucoma, for patients who cannot undergo SAP, and for assessing peripheral visual field beyond 24–30 degrees. However, kinetic perimetry results depend on the examiner’s skill, which can make progression assessment difficult 1).
Representative measurement programs of the HFA include the following 1)4).
Since about 90% of glaucoma develops within the central 30°, 24-2 or 30-2 is standard for follow-up 1). When macular damage is suspected on OCT, additional 10-2 testing is recommended. The EGS does not recommend reducing the frequency of 24/30° testing with 10-2 testing 3).
SITA Algorithm
SITA Standard: Approximately 7 minutes per eye. Reduces test time by about half while maintaining accuracy equivalent to full threshold 3).
SITA Fast: Approximately 4 minutes per eye. Useful for screening and reducing patient burden, but variability is slightly larger.
SITA Faster: Approximately 2 minutes per eye. Reduces SITA Standard test time by 50%.
Full Threshold: Most accurate but longest test time. Required when using size I or II stimuli6).
Octopus Perimeter Algorithms
Dynamic Strategy: Recommended for glaucoma diagnosis and follow-up3).
TOP Strategy: Allows short test time but has different characteristics from SITA and Dynamic Strategy3).
G1 Program: Test point arrangement considering the dense central distribution of retinal ganglion cells.
Eye Suite™: Enables progression assessment mainly using trend analysis.
SAP results consist of the following components1)4).
Measured Threshold / Grayscale: Grayscale is useful for grasping the rough pattern of visual field defects, but it displays interpolated data between test points, so it should be used as a reference only, and actual measured values should be confirmed.
Total Deviation (TD): Shows the deviation of each test point from age-matched normal values1). Includes the effect of overall sensitivity reduction due to cataract or miosis.
Pattern Deviation (PD): An index that subtracts overall sensitivity reduction to highlight localized abnormalities1). Particularly useful when cataract or corneal opacity is present.
GHT (Glaucoma Hemifield Test): Divides the upper and lower hemifields into five symmetrical zones considering the course of the retinal nerve fiber layer, and compares the differences between them for judgment1)4). It is judged in five categories: “Outside normal limits,” “Borderline,” “Generalized reduction of sensitivity,” “Abnormally high sensitivity,” and “Within normal limits.” As a standalone evaluation method, it has the highest detection power for glaucoma.
| Index | Meaning | Characteristics |
|---|---|---|
| Mean Deviation (MD) | Average sensitivity difference from normal | Decreases with progression |
| Visual Field Index (VFI) | Percentage of normal visual field | Weighted toward central visual field |
| Pattern Standard Deviation (PSD) | Degree of localized sensitivity loss | Increases in early to moderate stages |
Mean Deviation (MD): Indicates the degree of overall visual field loss compared to normal. It is the most widely used measure for evaluating glaucomatous visual field damage1)2)3).
Visual Field Index (VFI): Expresses the visual field as a percentage of a normal age-corrected visual field, with greater weight given to the central area. Similar to MD but less affected by cataracts2)3).
Pattern Standard Deviation (PSD): Indicates the degree of localized sensitivity loss within the visual field. It increases in early to moderate stages but decreases in advanced stages due to overall sensitivity loss2)3). PSD and LV should not be used for trend analysis2)3).
The following Anderson-Patella classification is used to determine glaucomatous visual field damage1). A diagnosis of glaucomatous visual field damage is made if any of the following criteria are met.
The reliability of test results is evaluated using the following indices1)4).
Since the first test often has low reliability due to insufficient patient familiarity, it is advisable to perform a second test early. Evaluate data considering learning effects and reliability1).
The 10-2 test is a program that precisely measures the central 10° at 2° intervals. It is useful when visual field defects involve the fixation point or are near the fixation point4)5). Additionally, even if the 24-2 or 30-2 test is normal, if OCT suggests thinning of the inner retinal layers in the macula, it is recommended to add the 10-2 test to detect early central visual field defects5). Central defects may also occur in preperimetric glaucoma.
GHT divides the upper and lower hemifields into five symmetrical zones considering the course of the retinal nerve fiber layer, and compares the differences between corresponding zones. Since glaucomatous visual field defects are characterized by asymmetry between the upper and lower hemifields, GHT directly reflects this feature1). It is considered to have the highest detection power for glaucoma among single evaluation methods. However, even if GHT is “outside normal limits,” it does not necessarily mean glaucoma; correlation with other clinical findings is necessary.
Detection of visual stimuli depends on the neural pathway: photoreceptors → bipolar cells → retinal ganglion cells (RGCs) → lateral geniculate nucleus → occipital cortex. Visual field defects in glaucoma result from damage to RGCs1).
The three main types of RGCs are as follows:
SAP uses non-selective white stimuli, stimulating multiple RGC types simultaneously. Due to this redundancy, a considerable number of RGCs may be lost before visual field defects become apparent on SAP.
The axons of RGCs form the retinal nerve fiber layer (RNFL), which is divided into three regions: nasal fibers, papillomacular bundle, and arcuate fibers.
Glaucomatous visual field damage shows characteristic patterns associated with structural changes1). Early damage tends to occur in the Bjerrum area, 5° to 25° from fixation. Damage to arcuate fibers produces arcuate scotomas (Bjerrum scotomas), which become step-like defects on the nasal side. Glaucomatous visual field defects do not cross the horizontal midline.
Nasal fibers and the papillomacular bundle are preserved until late stages of the disease, so even in advanced glaucoma, a “visual island” remains in the central or temporal area.
In myopic eyes, localized RNFL defects due to peripapillary pits and corresponding visual field defects have been reported7). Scotomas from pits resemble glaucomatous scotomas, so careful differentiation is needed7).
Staging of visual field damage according to EGS is as follows2)3):
Higher mean deviation indicates greater risk of blindness.
There are two approaches for assessing glaucoma progression: event analysis and trend analysis1)2)3).
Event analysis: Determines whether the change from baseline exceeds a preset threshold. Used in large RCTs (EMGT, AGIS, CIGTS, UKGTS)2)3). It requires confirmatory testing and has the disadvantage of making longitudinal assessment difficult in areas with reduced sensitivity.
Trend analysis: Calculates the rate of progression (dB/year or %/year) through longitudinal regression analysis of mean deviation or visual field index2)3). It allows continuous assessment from early to advanced stages.
Recommended Testing Frequency
First 2 years after diagnosis: Three SAP tests per year are recommended2)3)
Determining progression rate: Typically requires at least 2 years and sufficient number of tests2)3)
Ocular hypertension: Frequent testing is not necessary2)
After progression rate is established: Adjust testing frequency based on observed progression rate and disease stage2)3)
Assessment in Advanced Stages
Complementarity with OCT: Structural assessment by OCT is useful in early stages, but has limitations in advanced stages due to floor effect1)
Visual field testing is the mainstay: In advanced glaucoma eyes, SAP is the primary method for progression assessment1)
Potential of OCT-A: May be less affected by floor effect than RNFL measurement1)
Impact on QoL: Since there are differences by visual field region, local progression assessment is also necessary1)
All major glaucoma clinical trials have used SAP4)5). Alternative methods include SWAP (short-wavelength automated perimetry) and FDT (frequency doubling technology).
SWAP: Uses the K-cell pathway, measuring with a blue stimulus on a yellow background. It may detect visual field defects up to 5 years earlier than SAP. SITA SWAP has improved test time and variability. However, inter-test variability is greater than SAP, and it is affected by cataracts.
FDT: Preferentially targets the M-cell pathway. It has smaller inter-test variability than SAP and may be advantageous for progression monitoring. The Matrix version has improved spatial resolution.
Standard Goldmann size III is larger than Ricco’s area (critical area for complete spatial summation) for most test points in the central visual field, limiting detection sensitivity for shallow defects6). Small stimuli of size I and II have significantly higher signal/noise ratios and can reveal shallow defects not detectable with standard size III6). In patients with chiasmal compression, visual fields that were normal with size III were detected as bitemporal superior defects with size I and II6).
At least five visual field measurements are required to determine progression, and more measurement points are desirable 1). For newly diagnosed patients, three tests per year are recommended during the first two years 2)3). Higher testing frequency makes progression assessment easier 1). Trend analysis typically requires at least two years of follow-up and a sufficient number of tests 2)3). Confirmatory tests are essential for event analysis.
- 日本緑内障学会. 緑内障診療ガイドライン（第5版）. 日眼会誌. 2022;126:85-177.
- European Glaucoma Society. Terminology and Guidelines for Glaucoma, 5th Edition. 2020.
- European Glaucoma Society. Terminology and Guidelines for Glaucoma, 6th Edition. Br J Ophthalmol. 2025.
- American Academy of Ophthalmology. Primary Open-Angle Glaucoma Preferred Practice Pattern®. 2020.
- American Academy of Ophthalmology. Primary Open-Angle Glaucoma Suspect Preferred Practice Pattern®. 2020.
- Tsai NY, Horton JC. Smaller spot sizes show bitemporal visual field defects missed by standard Humphrey perimetry. Am J Ophthalmol Case Rep. 2025;40:102448.
- Kita Y, Hollό G, Narita F, Kita R, Hirakata A. Myopic peripapillary pits with spatially corresponding localized visual field defects: a progressive Japanese and a cross-sectional European case. Case Rep Ophthalmol. 2021;12:350-355.
