S INCE the 1956 report ofNorman’3 it has
been customary to refer to biconvex
subdural hematomas as “chronic” and
crescen t-sh aped su bdural hem a tom as as “acute.” The present investigation was undertaken to determine whether a valid
estimation of the age of a subdunal hematoma
can be made from its shape on carotid
angiograms. MATERIAL AND METHOD