Having occasion some twenty years ago to study
the literature of acute infection of the leptomeninges
from inflammatory foci in the nose, nasal accessory
sinuses, and pharynx, the writer was much impressed
by the fact that in almost every case published in
which the author had mentioned the pathway by which
the infection had passed from the peripheral focus to
within the cranium, the lymphatic system either was
stated to be the route or it was suggested that this
was the path involved.
Equally remarkable was it that in the numerous
cases which had been studied up to that time, no attempt
had been made to demonstrate microscopically
the pathway of infection.
Moreover, a direct continuity between the
lymphatic vessels of the peripheral parts and the
intradural structures was unknown to anatomists. A
lymphatic system begins in the dura mater and drains
through various of the foramina, in the base of the
skull into the deep cervical lymph nodes; this system
is closed, however, on the inner side having no
communication with the pia-arachnoid spaces.