Abstract
Purpose: :
Pulsar perimetry employs a 5° diameter circular waveform stimulus, the contrast of which decreases towards its periphery, which is isoluminant to the backround of 100asb. The purpose was to determine the learning effect for Pulsar Perimetry in normal individuals naive to Standard Automated Perimetry (SAP), in patients with ocular hypertension (OHT) who were experienced in SAP and in patients with open angle glaucoma (OAG) also experienced in SAP.
Methods: :
79 age-matched individuals (25 normal, 27 with OHT and 27 with OAG) attended for perimetry on five occcasions, each separated by one week. At each visit, both eyes were examined with Program T30W of the Pulsar Perimeter and with Program 24-2 and the SITA Standard algorithm of the Humphrey Field Analyzer. The right eye was always examined before the left eye. The order of the algorithm was randomized within individuals and varied over each of the five visits. Separate Analysis of Covariance (ANCOVA) was undertaken for Central Mean Sensitivity, Peripheral Mean Sensitivity, Mean Deviation, Mean Defect, Pattern Standard Deviation, Loss Variance and examination duration. Age, gender, diagnostic group and order of algorithm were considered as between-subjects factors and eye and visit as within-subjects factors. The Main Outcome Measures were (1) Change over the five visits, in each eye, of each of the visual field indices as a function of diagnostic group and (2) Change over the five visits at each location, in each eye, in the number and magnitude of the Total Deviation probability values and in the Comparison probability values, respectively, as a function of diagnostic group.
Results: :
The primary outcome variable Mean Defect (md) remained clinically stable over the five visits. For the normal individuals, the group mean md in the right and left eye at Visit One was -0.17dB (SD 1.82) and -0.50dB (SD 1.44), respectively, and at Visit Five 0.08dB (SD 1.88) and -0.51dB (SD 1.39). For the individuals with OHT, the group mean md in the right and left eye at Visit One was 0.05dB (SD 1.54) and 0.01dB (SD 1.94), respectively, and at Visit Five -0.17dB (SD 1.80) and -0.09dB (SD 1.41). For the individuals with OAG, the group mean md in the right and left eye at Visit One was 1.08dB (SD 2.58) and 1.18dB (SD 2.66), respectively, and at Visit Five 1.52dB (SD 3.38) and 1.23dB (SD 2.93).
Conclusions: :
In general, there is no residual learning effect for Pulsar Perimetry in those individuals experienced in SAP.
Keywords: perimetry • learning