Aus der Klinik und Poliklinik für Augenheilkunde (Direktor Univ.- Prof. Dr. Stefan Clemens) der Medizinischen Fakultät der Ernst-Moritz-Arndt-Universität Greifswald Thema: Peripheral Dynamic Stereovision – A Novel Stereoscopic Test Inaugural - Dissertation zur Erlangung des akademischen Grades Doktor der Naturwissenschaften in der Medizin (Dr. rer. med.) der Medizinischen Fakultät der Ernst-Moritz-Arndt-Universität Greifswald 2009 vorgelegt von: Michael Broschart geb. am: 28.01.1976 in: Landstuhl Dekan: Prof. Dr.rer.net. H.K. Kroemer 1. Gutachter: Prof. Dr.med. S. Clemens 2. Gutachter: Prof. Dipl.-Ing. Dr.med. H. Witte (3. Gutachter:) Ort, Raum: Greifswald, Konferenzraum der Kliniken für Neurologie und Neurochirurgie Tag der Disputation: 15.02.2010 Table of Contents I. Table of Contents I. TABLE OF CONTENTS ............................................................................................................................................. 1 II. LIST OF FIGURES ................................................................................................................................................... 2 III. LIST OF TABLES ..................................................................................................................................................... 3 IV. ABSTRACT ........................................................................................................................................................... 4 PART I – INTRODUCTION .................................................................................................................................... 5 1. INTRODUCTION .......................................................................................................................................... 5 1.1 MOTIVATION ................................................................................................................................................... 5 1.2 ORGANISATION OF THE THESIS ............................................................................................................................ 7 2. THEORETICAL BACKGROUND ...................................................................................................................... 9 2.1 THE HUMAN VISION ......................................................................................................................................... 9 2.2 VISUAL FIELDS AND RETINAL ORGANIZATION ......................................................................................................... 9 2.3 PERIPHERAL VISION AND PERCEPTION OF MOTION ................................................................................................ 12 2.4 OCULAR MOTILITY .......................................................................................................................................... 14 2.5 THE OPTOKINETIC NYSTAGMUS ......................................................................................................................... 16 2.6 STEREOSCOPIC VISION ..................................................................................................................................... 20 2.6.1 Physiology of Stereopsis ........................................................................................................................ 21 2.6.2 Criteria of Stereopsis ............................................................................................................................. 23 2.6.3 Testing of stereopsis .............................................................................................................................. 26 2.6.4 Frisby Stereotest .................................................................................................................................... 32 PART II – MATERIALS AND METHODS ................................................................................................................ 35 3. MATERIALS AND METHODS ...................................................................................................................... 35 3.1 OVERVIEW OF THE EXPERIMENTAL SETUP ............................................................................................................ 35 3.2 STRUCTURAL AND ELECTROMECHANICAL HARDWARE ............................................................................................ 36 3.3 ROTATING DRUM AND STIMULUS PATTERN ......................................................................................................... 38 3.4 OPTICAL COMPONENTS ................................................................................................................................... 42 3.5 ERGONOMICS AND SETTINGS ............................................................................................................................ 44 3.6 DATA ACQUISITION AND PROCESSING ................................................................................................................. 45 3.7 PERFORMANCE AND LIMITS OF THE PROTOTYPE .................................................................................................... 48 4. EXPERIMENTAL PROCEDURE .................................................................................................................... 50 4.1 SELECTION OF SUBJECTS AND EXPERIMENTAL CONDITIONS ..................................................................................... 50 4.2 EXPERIMENTAL PROTOCOL ............................................................................................................................... 51 4.3 CONSIDERATION OF SYSTEMATIC ERRORS ............................................................................................................ 52 PART III ‐ RESULTS AND EVALUATION ............................................................................................................... 55 5. RESULTS AND EVALUATION ...................................................................................................................... 55 5.1 PRESENTATION OF THE RESULTS ........................................................................................................................ 55 5.1.1 Voluntary Feedback ............................................................................................................................... 56 5.1.2 Involuntary Feedback ............................................................................................................................ 59 5.1.3 Position of Peripheral Object Perception ............................................................................................... 64 5.2 STATISTIC CONSIDERATION ............................................................................................................................... 67 5.3 CONCLUSIONS ................................................................................................................................................ 70 5.4 IMPROVEMENT AND OPTIMIZATION OF THE TEST PROCEDURE ................................................................................. 72 1 | 97 Table of Contents PART IV – DISCUSSION ...................................................................................................................................... 76 6. DISCUSSION ............................................................................................................................................. 76 6.1 SIGNIFICANCE OF PERIPHERAL DYNAMIC STEREOVISION ......................................................................................... 76 6.2 THE NEED OF OBJECTIVE TESTS AND CRITERIA OF ASSESSMENT ............................................................................... 79 6.3 COMPARISON OF THE RESULTS/SOLUTIONS WITH LITERATURE ................................................................................. 82 6.4 COMMERCIAL APPLICABILITY ............................................................................................................................. 85 PART V ............................................................................................................................................................. 88 7. SUMMARY ............................................................................................................................................... 88 8. REFERENCES ............................................................................................................................................. 92 ANNEX ............................................................................................................................................................. 97 MATERIAL SAFETY AND DATA SHEET OF POLYSTYRENE ........................................................................................................ 97 II. List of Figures Figure 2.1: Human visual field. .................................................................................................................................... 10 Figure 2.2: Distribution of cones and rods over the retinal surface ........................................................................... 11 Figure 2.3: Dependence of visual acuity on the position in the visual field and the lightning conditions. ................. 13 Figure 2.4: Arrangement of extraocular muscles. ....................................................................................................... 15 Figure 2.5: Synoptic overview of the basic eye movements for gaze shifting and stabilization. ...............................