INFLAMMATION OF THE CEREBRAL SINUSES. 235 



with these changes we generally find those of otitis interna, and ex- 

 tensive caries of the petrous bone ; viz., destruction of the drum, 

 absence of the ossicula, polypoid proliferations of the mucous mem- 

 brane, the tympanum full of pus, which also infiltrates the labyrinth, 

 cochlea, and mastoid cells. 



SYMPTOMS AND COURSE. Chronic pachymeningitis, which causes 

 thickening of the dura mater, and its firm adhesion to the cranium 

 and ossification of the thickened layer, may be accompanied by 

 headache and other symptoms ; but these are not at all characteristic 

 and do not show us what the disease is. The symptoms and course 

 of acute pachymeningitis externa also are almost always so modified 

 by the symptoms of the original disease, by complications with ex- 

 tensive inflammation of the pia mater, and by extension of the in- 

 flammation to the cerebral sinus with its results, that it is impossible 

 to give a pure description of the disease. If an injury of the skull, 

 or, still more, if a caries of the temporal bone, due to otorrhoea, be 

 accompanied by unusually severe and extensive pain in the vicinity 

 of the diseased bone, by fever, vomiting, dizziness, noises in the ear, 

 twitching, delirium, and other symptoms of irritation of the brain, 

 which are subsequently followed by those of depression, and finally 

 by general paralysis, we may conclude that the disease of the bone 

 has at first caused inflammation of the dura mater, and later, diffuse 

 inflammation of the pia mater. The first stage is often short and 

 indistinct, and, on the first visit or at their reception into the hospi- 

 tal, we find the patients in deep sopor. But even in such cases the 

 above diagnosis may be made with tolerable certainty, if we find an 

 injury of the skull, or particularly a chronic otorrhcea, and can dis- 

 cover no other causes for the brain-disease. 



The symptoms induced by inflammation and thrombosis of the 

 cerebral sinuses are always accompanied by those of meningitis as 

 given above; hence it will be enough to limit ourselves to pointing out 

 under what circumstances we are to suspect inflammation or thrombo- 

 sis of a cerebral sinus, when we have a meningitis or encephalitis ac- 

 companying caries of the petrous bone. From the great frequency 

 of this complication, I think it is well to keep in view its possibility 

 and even its great probability, although the very doubtful signs of the 

 disease should be absent. The suspicion will acquire more probabil- 

 ity, should we observe a symptom of thrombosis of the transverse 

 sinus that was given by Gerhardt with great acuteness, namely, less 

 fulness of the jugular vein drawing its blood from the obstructed sinus. 

 The same would be true if we found a symptom given by Griesinger, 

 which was only observed in one case, a circumscribed painful oedema 

 behind the ear ; although, in caries of the mastoid process, this redema 



