ARACHNOIDITIS is a comparatively new entity in the field of neuro-ophthalmology. It is an inflammation ofhe leptomeninges, which may be localized or diffuse, even to the extent of involving the entire central nervous system.
HISTORICAL REVIEW
The pathology of the serous form of meningitis was first described by Quincke in 1893, and in 1898 Schlesinger1 described the localized cystic form. It was Horrax,2 working at Cushing's clinic, who gave this condition a new clinical interpretation when he presented 33 cases of pseudocerebellar tumors which on operation proved to be cases of arachnoiditis.In 1929 Cushing and Eisenhardt3 were the first to recognize the chiasmic form when, in one of the classic monographs on chiasmal tumors emanating from Cushing's clinic, they mentioned chronic cisternal arachnoiditis as a condition to be differentiated from tumors of the chiasm. However, the importance of this contribution was overlooked in the larger and