Abstract
Purpose: :
To assess the concordance of advanced VFDs, assessed with a newly designed portable and hand–held VF testing device, the Tuebingen Mobile Campimeter (TMC), and with conventional slightly supraliminal SAP.
Methods: :
Thirty–one eyes of 31 patients suffering from advanced retinal nerve fibre layer (RNFL) loss (n=13), hemianopia (n=12) or tapetoretinal degeneration (TD; n=6) and 6 healthy subjects were examined with the Octopus 101 perimeter (Haag–Streit AG, Koeniz, Switzerland) as a reference standard, using a 191 stimulus grid (reduced to 84 stimuli for analysis, only absolute scotomas considered) within the central 30° VF. Subjects subsequently were examined with the TMC using the same 84 stimulus points for threshold–related, slightly supraliminal (stimulus luminance 320–370 cd/m²) static perimetry. Proportion and location of both, discordantly perceived stimuli among all presented stimuli and positive discordant stimuli (perceived at the TMC but not at the Octopus 101) among the discordant points were assessed for the entire sample and each diagnosis group separately, and the following characteristics were considered: Accuracy (acc; proportion of concordant responses), sensitivity (sens; stimuli concordantly not perceived) and specificity (spec; stimuli concordantly perceived at both devices). Furthermore the examination duration at the TMC was evaluated.
Results: :
If analysed by patient per diagnosis group, the average acc was highest in healthy (97.9%; 95%CI: 97–98,5%), lowest in RNFL loss (80.6%; 95%CI: 77.3–83.5%); average sens was highest in TD (94.5%; 95%CI: 82.9–98.4% ), lowest in healthy (59.1%; 95%CI: 26.3–85.3%); average spec was highest in healthy (98.1%; 95%CI: 96.6–98.9%), lowest in TD (77.4%; 95%CI: 62.1–87.7%). For the entire sample the average acc was 89.4% (95%CI: 85.8–92.2%), sens was 84.8 (95%CI: 76.5–90.6%), and spec was 87.4% (95%CI: 82.7–90.9%). The percentage of positive discordant stimulus points among all discordant points for the entire sample was 35% (143/411; 95%CI: 30–40%). The median examination duration with the TMC was 4:50min (min. 2:10min, max. 5:40min).
Conclusions: :
The results indicate that the TMC is a feasible device for documented detecting of VF loss. Comparable results to those of the Octopus 101 were achieved.
Keywords: perimetry • visual fields