Changes of glaucomatous field defects

Abstract

The analytical programme Delta was used to determine longterm fluctuation and accuracy of measurement of the programme 31 of Octopus when used on glaucoma patients. Programme 31 examines the 30 degrees field. The test locations are arranged in a square grid with 6 degrees resolution. The programme Delta determines and compares 1) the disturbed area in %; 2) the total loss, the total sensitivity being around 2000 dB; 3) the loss in dB per mean number of disturbed points. Thirty-two eyes of 22 patients with established glaucomatous field defects were examined twice within two to six days and two months later again twice. The size of the disturbed area served for classification of our sample into three groups: 1st group: disturbed area 1-33%; 2nd group: disturbed area 34-66%; 3rd group: disturbed area 67-100%. Long-term fluctuations and accuracy of measurement could be determined as respectively follows: 1) Disturbed area between 0.7 +/- 8% in group 3 and 1.7 +/- 13% in group 2. 2) The total loss increases proportionately to the disturbed area and was 4.9 +/- 29.2 dB in group 1 and 31.8 +/- 82.4 dB in group 3. 3) The total loss per mean number of disturbed points was 0.5 +/- 2 dB in group 1 and 0.3 +/- 1.2 dB in group 2. This signifies that if the learning effect is over, changes of more than 2 dB, especially if several adjacent points are affected, are a significant loss. The learning effect, as determined in an earlier study, may go up as high as 2 dB per point.

Reliability of Visual Field Testing in a Telehealth Setting Using a Head-Mounted Device: A Pilot Study

“…29,50 In general, comparing perimetry results between different instruments and manufacturers may be difficult and should be interpreted with caution. 51 Test-retest reproducibility 37 was clearly superior in the cohort with stable defects compared with the cohort without ocular disease, only when comparing the agreement of VRVF V 2 and V 3 based on the statistically significant P value (Fig. 3A).…”

“…Test-retest reproducibility 37 was clearly superior in the cohort with stable defects compared with the cohort without ocular disease, only when comparing the agreement of VRVF V 2 and V 3 based on the statistically significant P value (Fig. 3A).…”

“…The first 2 VRVF examinations (V 0 and V 1 ) were not included in the data analysis to correct for the learning curve of automated perimetry testing seen in both normal participants 33,34 and glaucoma or suspected glaucoma participants. [35][36][37] Remote, unassisted VRVF examinations (V 2, V 3, and V 4 ) were compared (1) with one another to assess test-retest reliability and (2) against the baseline SAP examination to evaluate accuracy. At this stage in the VRVF device's development, the normative database was not rigorous enough to determine accurate mean deviations (MD) or pattern SDs (PSD).…”

Detecting the Progression of Normal Tension Glaucoma: A Comparison of Perimetry, Optic Coherence Tomography, and Heidelberg Retinal Tomography

“…Structural measurements usually are more stable than functional measurements [ 10 ]. Another advantage of structural measurements is that, in contrast to perimetry, they are unaffected by any learning effects [ 11 ]. The discussion of whether structural measurements can detect glaucoma progression earlier than functional measurements, or vice versa, is still ongoing.…”