Single and Multiple Stimulus Static Perimetry in Glaucoma; The Two Phases of Perimetry

I. Introduction.- II. Some Basic Facts from Visual Physiology.- Visual Field Examination is a threshold measurement.- Methods of measurement.- Factors which determine the difference threshold.- Physical characteristics of the stimulation.- Determination of the position of the stimulus.- Level of luminance before examination.- Background luminance.- Luminance of stimulus.- Size of stimulus.- Sharpness of stimulus.- Presentation time.- Movement.- Chromaticity of the stimulus.- Fixation target.- Receptor and neural mechanisms.- Anatomical considerations.- Adaptation.- Definition and mechanisms.- Temporal adaptation; adaptometry.- Adaptation and the two receptor systems.- Steady state adaptation.- Adaptation and difference threshold.- Adaptation and topography of the light sensitivity; adapto-perimetry.- photopic level.- scotopic level.- mesopic level.- Equivalent background; the relationship between adaptometry and adaptoperimetry.- Conclusion.- Spatial interaction.- Psychophysical findings.- Laws of summation.- Summation and inhibition.- Electrophysiological findings.- Receptive field.- Summation area and receptive field.- Temporal interaction.- Psychophysical findings.- Data from the literature.- Broca-Sulzer effect.- Critical fusion frequency.- Local adaptation.- Movement.- Detection of movement.- Detection of direction.- Fixation.- Physiological fixation nystagmus.- Fixation and visual field examination.- III. The Fundamental Principles of Static and Kinetic Perimetry.- Static Perimetry.- Kinetic Perimetry.- The fundamental difference between static and kinetic perimetry.- Fundamental limits of the accuracy of kinetic perimetry.- movement; successive lateral spatial summation.- gradient of sensitivity.- sensitivity curves for static and kinetic stimuli.- influence of reaction time.- detection and reproducibility.- influence of direction of movement.- Conclusion.- IV. Choice of the Conditions of Examination.- Choice of adaptation level.- Selective detection of disturbances in the photopic or the scotopic system.- Visual field examination at mesopic adaptation levels.- Threshold examination at mesopic and photopic levels.- Intra-individual variation at various adaptation levels.- Influence of preretinal factors.- Scotopic perimetry.- High-photopic adaptation levels.- Conclusion.- Choice of stimulus size; spatial interaction and visual field examination.- Spatial interaction in the normal visual field.- Constant size of stimulus.- Dubois-Poulsen’s work: spatial interaction and visual field defects.- Problems of kinetic perimetry.- Inter-individual variation of the summation exponent.- Results obtained by other authors.- Inhibition in perimetric examinations.- Conclusion: Choice of stimulus size.- The significance of the examination of spatial summation in visual field defects.- Choice of presentation time; temporal interaction and visual field examination.- Temporal interaction in the normal visual field.- Position.- Adaptation.- Stimulus size.- Arguments for the use of a short presentation time.- intra- and inter-individual variation.- total duration of the examination.- latent period for eye movements.- normal fixation movements and temporal summation.- subjective experience.- abnormal temporal summation in visual field defects.- technical possibilities.- kinetic perimetry.- Conclusion.- Local adaptation and visual field examination.- Local adaptation in the normal visual field.- Local adaptation and visual field defects.- Conclusion.- Some remarks about critical fusion frequency (C.F.F.) and colour in visual field examination.- V. The Place of Static and Kinetic Perimetry in the two Phases of Visual Field Examination.- Detection phase.- present-day kinetic perimetry.- number and position.- size of stimulus.- size of defect.- conclusions about number and position.- static and kinetic perimetry in the detection phase.- subdivision of detection phase.- two separate halves of the visual field.- repeat examination.- static and kinetic perimetry in visual field defects.- Assessment phase.- VI. Three Instruments for Single Stimulus Visual Field Examination.- The Goldmann perimeter.- The Tübinger perimeter.- The Double Projection Campimeter.- VII. Normal Values and Normal Variation of Thresholdmeasurements.- Normal values and inter-individual variation.- Kinetic perimetry with the Goldmann perimeter.- Static perimetry with the Goldmann perimeter.- Kinetic perimetry with the Tübinger perimeter.- Static perimetry with the Tübinger perimeter.- Kinetic campimetry with the Double Projection Campimeter.- Static campimetry with the Double Projection Campimeter.- Intra-individual variation.- Causes of intra-individual variation.- Size of intra-individual variation.- Size of luminance steps and intra-individual variation.- Significance of defects.- Variations between successive examinations.- Influence of age.- Reaction time.- Position of the eye in the orbit.- Senile miosis.- Senile lens opacities.- Senile degeneration of the visual system.- Oxygen shortage.- Blind spot.- Optic disc and blind spot.- Pericecal visual field.- Size and position of the blind spot.- Angioscotomata.- Normal angioscotomata.- Variation in the size of angioscotomata.- Conclusion.- Cartography and visual field.- VIII. Multiple Static Stimuli in the Detection Phase.- Specific problems of multiple stimuli.- Simultaneous approach to the threshold.- Supraliminal stimuli.- Neural interaction.- ‘Gestalt’ psychological phenomena.- Counting and indicating.- Localized attention.- Maximum number of stimuli.- Threshold level and variation.- Pseudo-variation.- Multiple stimuli and visual field defects.- Instruments for multiple stimulus visual field examination.- Method of Harrington and Flocks.- Instrument of Fincham and Sutcliffe.- Friedmann Visual Field Analyser.- description and critical discussion.- examination with the Visual Field Analyser.- normal visual field with the Visual Field Analyser.- The Visual Field Analyser in the detection phase.- Literature and introduction.- False-negative results.- False-positive results.- Screening.- Optimum visual field examination using multiple stimuli.- Two other detection methods.- Armaly’s method.- Gloster’s method.- IX. Preretinal Factors.- Pupil.- Senile miosis.- Lens.- Ametropia.- Image formation in the emmetropic eye.- Image formation in the ametropic eye.- Central ametropia scotoma.- Correcting lenses.- Peripheral ametropia; refraction scotoma.- Accommodation.- Presbyopia and fatigue of accommodation.- Accommodation spasm due to miotics.- X. Description of Visual Field Defects.- Topography.- Definitions.- Numerical topographic classification.- Intensity.- Absolute and relative defects.- Quantitative determination of relative defects in static perimetry.- Intensity of defects in kinetic perimetry.- Distribution of intensity in defects.- XI. The Examination Procedure in Practice; Experiences with the Multiple Stimulus Method for the Detection of Glaucomatous Defects.- Examination procedure.- Research procedure.- Duration of the examination.- Organization.- Glaucomatous defects.- Early defects in the opposite hemifield.- Demonstration of 18 visual fields with glaucomatous defects.- Results of the comparative study.- Number and position of stimuli in the Visual Field Analyser.- Comparative study of threshold measurements.- Conclusion.- XII. Summary and conclusion.- References.