The first case of zonular opacity of the cornea, reported by Dixon1 in 1848, was an instance of the primary type. Since that time there have been reported numerous cases of the secondary type, which develops after some degenerative change in the eye. Comparatively few cases of the primary type have been reported.
REPORT OF A CASE
C. S., a hatter aged 58, complained that his vision was failing and that he suffered from severe headaches. The results of a careful physical examination were negative.
With the exception of the affected portion of the corneas, the anterior segment of each eye was normal. The vision in the right eye was 20/30, and in the left eye 20/40. With glasses, it improved to 20/20 in the right eye and to 20/30 in the left eye. The field of vision and the ocular tension were normal.
With the slit lamp