Abstract
Purpose::
Fundus- or microperimetry allows fundus controlled examination of the central visual field. Besides static perimetry an automated kinetic perimetry is available for a short time. Especially the detection of small scotomas is facilitated within shorter examination times. Aim of this study was to evaluate the reliability and accuracy of kinetic fundus perimetry in healthy volunteers as well as in patients with macular pathologies.
Methods::
Kinetic perimetry was performed twice with identical strategy using the MP1 (Nidec Technologies Inc.) in 10 eyes of 10 healthy volunteers (23-40 years of age) as well as in 10 eyes of 10 patients with different forms of retinal pathology (35-79 years of age). In the first group the physiologic scotome of the blind spot was measured while the latter presented as well demarcated absolute scotoma. We used 6 isopters in 8 radial directions with a maximal radius of 20 degrees and Goldmann III stimuli in all eyes included. The area of the visual field defect was evaluated as well as concordance with morphologic borders of the optic disc or retinal pathology.
Results::
Standard deviation between both measurements increased with increasing field defect, i.e. lower luminance from 4 to 8 deg2 and from 3 to 14 deg2, respectively. Prominence of the border of the disc led to smaller scotomas as well as higher reflectivity as in geographic atrophy caused by AMD. Retesting after false stimulus recognition inside the scotoma resulted in increase of reliability by a factor of 2.
Conclusions::
Kinetic fundus perimetry with the MP1 permits a reliable and fast detection of scotomas especially when they are concordant with retinal pathology. In comparison to static perimetry the delineation of scotomas hereby is possible very exactly within short examination times. Light scattering may influence results especially with bright stimuli. Variation between different examinations can be minimized by retesting of questionable answers. The increase of variance for hardly detectable stimulus intensities is already known from other visual field defects. Light scattering might influence accuracy, therefore lower stimulus intensities should be used.
Keywords: perimetry • visual fields • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)