No one can have experience of intracranial surgery without perceiving how difficult it may be to localize an intracranial tumor, and how frequently operation is performed without the tumor being found. The object of this paper is to show that surgical intervention which falls short of removal of the tumor may so alter the signs and symptoms of the tumor as to enable a more accurate localization of its position to be made. Changes of a similar nature sometimes occur in cases of tumor of the spinal cord after lumbar puncture has been performed. These are easy to interpret and may therefore be conveniently considered before the more complicated changes that attend surgical intervention in cases of intracranial tumor.
THE EFFECT OF LUMBAR PUNCTURE IN TUMORS OF THE SPINAL CORD
It is well known that withdrawal of cerebrospinal fluid by lumbar puncture may aggravate the signs and symptoms of a