Automated perimetry: a report by the American Academy of Ophthalmology

The purpose of this document is to summarize and evaluate the effectiveness of new automated perimetry tests and algorithms in diagnosing glaucoma and detecting disease progression.

A literature search on automated perimetry retrieved over 300 citations from 1994 to 2001, of which 71 were selected as relevant to this assessment. The quality of the evidence obtained from these studies was assessed by the methodologist.

The four automated perimetry techniques described in this assessment are short wavelength automated perimetry (SWAP), frequency doubling technology perimetry (FDT), high-pass resolution perimetry (HPRP), and motion automated perimetry (MAP). The algorithms described are Swedish interactive threshold algorithm (SITA) and SITA fast. With the exception of SWAP, these techniques and algorithms reduce testing time and inconsistent patient performance when compared with conventional full threshold testing.

Short wavelength automated perimetry detected visual field loss earlier than standard threshold automated perimetry, with a sensitivity and specificity of about 88% and 92% respectively. However, it is a lengthy, demanding test, is sensitive to media opacities, and has a greater magnitude of long-term fluctuation compared with standard threshold automated perimetry, which make it difficult to assess disease progression accurately. When compared to standard threshold automated perimetry, FDT perimetry showed sensitivity and specificity greater than 97% for detecting moderate and advanced glaucoma, and sensitivity of 85% and specificity of 90% for early glaucoma. As FDT perimetry has a short testing time and is resistant to blur and pupil size, it may be a useful screening tool. In a longitudinal study, high-pass resolution perimetry was more effective than standard threshold automated perimetry in monitoring progressive glaucomatous loss, detecting progression at a median of 12 months earlier in 54% of patients studied. Motion automated perimetry demonstrated usefulness in detecting early glaucomatous visual loss in a longitudinal study. Studies on SITA demonstrated greater sensitivity and reproducibility and less intertest variability when compared to standard full threshold testing and a 50% reduction in testing times. A study comparing standard full threshold, SITA, and SITA fast found a sensitivity of 95% for the first two techniques and 93% for SITA fast. Long-term follow-up studies are needed to assess the ability of these techniques to detect progression of glaucoma over time.