著者

松本 長太

出版者

近畿大学

雑誌

近畿大学医学雑誌 (ISSN:03858367)

巻号頁・発行日

vol.14, no.1, pp.1-17, 1989-03-25

被引用文献数

6

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The physiological character of the pericentral visual field near the fixation point is not so well understood as in the central 30° visual field. In this paper a report is made on the influences of stimulus size and background illumination on the sensitivity of this area studied in normal subjects and patients with several eye diseases. According to the SARGON program of the automated perimeter Octopus 201,49 test points on a 2° grid in the pericentral area were tested in normal subjects. These test points were examined under the conditions of stimulus sizes 1,3 and 5 (the visual angles of 0.108°, 0.431° and 1.724°) and under the background luminances of 0.4,4 and 31.5 asb. In the normal subjects the sensitivity curve of this pericentral area was rather flat when large stimulus sizes were used. But within the range from 0.4 to 31.5 asb the background illumination did not affect the sensitivity curve of this area so remarkably as the stimulus size. Differential light sensitivity decreased with age and its decrease was more evident under the condition of smaller stimulus sizes. The influence of stimulus size of this area was then studied in patients with several eye diseases. In many of the patients with optic neuritis, chiasmal syndrome and optic tract diseases, the stimulus size 1 was more sensitive in detecting pericentral scotoma and hemianoptic changes than the standard stimulus size 3. Thus the present results suggested that a small static target such as the stimulus size 1 should be used to examine the pericentral visual field abnormalities in neuro-ophthalmological cases.