INFLAMMATION OF THE DURA MATER. 233 



hemiplegia, or else it is very incomplete ; but we must bear in mind 

 that haematoma occurs just at the place where the increased pressure 

 on one hemisphere is most readily transferred to the other, through 

 the free communication between the two sides in the anterior portion 

 of the skull, particularly when the haemorrhage comes on slowly. 

 Among the symptoms of haematoma, Griesinger also lays stress on 

 the almost constant contraction of the pupil, and is inclined to regard 

 this as a " symptom of irritation of the surface." In the previous 

 chapter I attempted to give another explanation of the contraction of 

 the pupil (which was also hypothetical) in diseases encroaching on the 

 space above the tentorium. 



TREATMENT. In the treatment of meningeal haemorrhages, the 

 same rules hold good as were given for that of cerebral haemorrhages, 

 and we may the rather refer to the former chapter, as it is impossible 

 to make an exact diagnosis between the two. 



If we consider the diagnosis of a haematoma as certain, we may, in 

 recent cases, apply leeches behind the ears, ice-compresses to the head, 

 and give a purge occasionally. In the latter stages, blisters or pustu- 

 lating ointments to the nape of the neck suffice. With this treatment 

 I have had very good results in two cases that I have observed ; still, 

 in spite of the very characteristic symptoms in these cases, there may, 

 possibly, have been an error of diagnosis. 



INFLAMMATIONS OF THE BRAIN AND ITS MEMBRANES. 



IN the following chapters we shall speak 1. Of inflammation of 

 the dura mater and its sinus. 2. Of inflammation of the pia mater, 

 with puro-fibrinous exudation. 3. Of tuberculous inflammation of the 

 pia mater, including acute hydrocephalus. 4. Of epidemic cerebro-spi- 

 nal meningitis ; and 5. Of inflammation of the brain-substance. Since 

 inflammation of the arachnoid cannot be distinguished from that of the 

 pia mater, we shall not treat separately of arachnitis. 



CHAPTER VII. 



INFLAMMATION OF THE DURA MATER, INFLAMMATION AND THROM 

 BOSIS OF THE CEREBRAL SINUS. 



IN the previous chapter we spoke of one form of pachymeningitis, 

 because, on account of the haemorrhage it causes, and its clinical 

 oourse, it is most suitably classed among meningeal haemorrhages. 

 Now we have only to speak of that form which, since Virchow's studies 

 <m haematoma of the dura mater, is called pachymeningitis externa. 



