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A Comparison between the Compass Fundus Perimeter and the Humphrey Field Analyzer
Giovanni Montesano1, Susan R Bryan2, David P Crabb2
1University of Milan - ASST Santi Paolo e Carlo, Milan, Italy; City, University of London, Optometry and Visual Sciences, London, United Kingdom; NIHR Biomedical Research Centre, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom.
Ophthalmology
|August 17, 2018
Summary
The Compass perimeter and Humphrey Field Analyzer show equivalent diagnostic precision for glaucoma detection. The Compass demonstrated superior test-retest variability in mean sensitivity measurements.
Area of Science:
- Ophthalmology
- Medical Devices
- Diagnostic Imaging
Background:
- Glaucomatous optic neuropathy (GON) diagnosis relies on visual field testing.
- Comparing diagnostic devices is crucial for clinical practice.
- The Compass (CMP) and Humphrey Field Analyzer (HFA) are key fundus perimeters.
Purpose of the Study:
- To evaluate the relative diagnostic precision of CMP versus HFA.
- To assess the test-retest variability of these two devices in detecting GON.
Main Methods:
- A multicenter, cross-sectional study enrolled 499 glaucoma patients and 444 normal subjects.
- Visual fields were tested using CMP (ZEST strategy) and HFA (SITA standard strategy).
- Diagnostic precision was compared using partial ROC curves; test-retest variability was assessed via mean absolute deviation and Bland-Altman plots for mean sensitivity (MS).
Main Results:
- Both devices demonstrated similar diagnostic precision for GON detection.
- Retinal sensitivity measurements were generally lower with CMP compared to HFA.
- CMP showed significantly better test-retest variability for mean sensitivity (MS) than HFA, especially in normal participants.
Conclusions:
- The diagnostic precision of CMP and HFA for glaucomatous optic neuropathy is comparable.
- CMP offers improved test-retest variability for mean sensitivity compared to HFA.
- These findings support the clinical utility of both devices, with CMP showing an advantage in repeatability.
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