Extra-dural hematoma of the posterior fossa (author's transl).

10 cases of posterior fossa extra-dural hematoma are reported and 100 other published cases reviewed. It appears that the sole clinical evaluation frequently leads to wrong or delayed diagnosis. In only one out of five cases the cerebellar signs and the palsy of one or several cranial nerves (VII, IX, X, XI, XII) are prominent. In contrast, all other cases do not present specific signs. Furthermore, the presence of a concomitant supratentorial traumatic lesion may contribute to prevent the finding of evidences for cerebellar extra-dural hematoma. The possibility for such hematoma must always been kept in mind when an occipital fracture is shown by radiography. Venous phases in carotid arteriography permit to ascertain the extradural hematoma if there is a displacement of the torcular Herophili or of the transverse sinus. Data from carotid arteriography may be normal and the lesion may be ascertained by vertebral arteriography which will demonstrate: anterior displacement of the basilar artery against the clivus--anterior displacement of posterior inferior cerebellar and posterior meningeal arteries--crescentic displacement of brain substance from the inner table--displacement of the venous sinuses.