Anatomic variations of the sinuses of the dura mater, however infrequent, may present puzzling diagnostic and operative problems in the presence of thrombophlebitis. Some of the variations are extremely rare. In this paper a hitherto unknown anomaly of the sigmoid sinus will be reported and a short description of most of the published observations which are important for the otologist will be given. In view of the existing differences in the nomenclature, in this paper the horizontal portion of the transverse sinus will be called the lateral sinus and the vertical portion will be called the sigmoid sinus.
REPORT OF A CASE
A 65 year old patient was operated on for septic thrombophlebitis of the right transverse sinus, but the sigmoid sinus could not be located; the patient died of purulent meningitis due to pneumococci of type III which originated from a deep epidural abscess of the right posterior fossa.