Capabilities of the portable perimeter in the examination of visual field of bedridden patients (preliminary results)

Abstract

PURPOSE. To study the capabilities of perimetry in patients who are physically unable to take and maintain the correct position at the stationary perimeter during the time required for examination.METHODS. The study examined 40 eyes (34 patients) with stage II–III glaucoma using the portable perimeter (PP) with patients in the sitting and lying positions. Screening perimetry with Humphrey Visual Field (HFA-II) performed in patients in the sitting position was used as control. In all cases, perimeter strategy of 30-2 was used involving presentation of 76 light stimuli in the zone of 30° from the gaze fixation point. To be able to compare the results obtained on HFA-II in the sitting position and on PP in the lying position, the results obtained with the help of PP in the sitting position were used as the "gateway group" (logical link).RESULTS. Comparison of the results obtained using the above-mentioned approaches revealed good visual comparability of perimeter maps with small individual deviations that require more detailed analysis on more clinical data using statistical and mathematical methods, which is a subject of further research. In that case, it will be necessary to take into account the presence of an orthostatic factor affecting intraocular blood flow at different positions of the patient.CONCLUSION. Portable perimetry is an effective method for examining the visual field of low-mobility and bedridden patients who are physically unable to undergo a perimetry examination on stationary devices.