Abstract
Purpose:
To study Damato Multifixation Campimetry Online (DMCO), a free of charge Internet-based visual field test. The focus was on: (i) the sensitivity and the specificity of DMCO in the detection of glaucomatous visual field loss and (ii) algorithms for the interpretation of DMCO results.
Methods:
A standard laptop, a wireless mouse and a 22" computer monitor was placed on a height-adjustable table. Participants were asked to wear their usual spectacles. DMCO is an automated supra-threshold test of the central 24° visual field using dark stimuli examining 42 fixation targets located sequentially on different parts of the computer screen. Three versions of DMCO exist; the different versions differ in visual stimuli: DMCO Standard uses black stimuli, DMCO Basic requires the patient to identify a numbered fixation target and DMCO Advanced incorporates light-grey, dark-grey and black stimuli. The three DMCO versions were tested in a blinded fashion. Fifteen algorithms were devised to define abnormality and these were evaluated using the Humphrey Visual Field Analyzer (HFA) 30-2 and the Glaucoma Staging System as gold standard. Receiver operating characteristic (ROC) curves were used to determine the algorithm demonstrating the greatest agreement between the DMCO version and the gold standard.
Results:
Fifty-two glaucomatous, 36 normal and 9 borderline glaucomatous patients participated. The algorithm demonstrating greatest agreement with the gold standard combined results from two successive DMCO Standard tests attaining sensitivity of 11.8%, 71.4%, 100% and 100% in eyes with mild, moderate, advanced and severe loss, respectively. A specificity of 98.1% was achieved in eyes without abnormal HFA results. Fifteen algorithms were created and the area under the ROC curves (AUC) ranged from 0.79 to 0.90. Median duration per eye to complete the DMCO Standard test was 86 seconds for participants in the control group and 125 seconds for participants with glaucoma.
Conclusions:
This study demonstrated that DMCO was able to find glaucomatous visual field defects in this preselected population. Future studies should evaluate DMCO in a non-selected population.