CEREBRAL APOPLEXY. 217 



tends to show that the hyperaemia of the brain induced by temporary 

 plethora is one of the most dangerous forms. Hypertrophy of the 

 left ventricle, particularly that form resulting from any extensive en- 

 darteritis deformans, plays an important part in the ruptures of cere- 

 bral vessels. In the latter case two dangerous factors unite the mor- 

 bid fragility of the vessels and the increased pressure of the blood on 

 them. Moreover, small arteries, in which there is otherwise a regular 

 pressure of the blood, and whose walls also maintain a nearly equal 

 tension during the systole and diastole of the heart, pulsate when 

 there is extensive atheromatous degeneration, and at every systole of 

 the heart the normal medium tension of their walls is decidedly in- 

 creased. It will be readily understood that this circumstance also in- 

 creases the liability of the vessels to rupture. Cerebral haemorrhages 

 so often depend on the complication in question, that, in doubtful 

 cases, the discovery of hypertrophy of the left ventricle and of a.n 

 atheromatous degeneration of the arteries may decide the diagnosis. 



Apoplexies occur at all times of the year ; occasionally, without 

 any known cause, cases accumulate remarkably. They have also 

 been observed at all times of the day, and statistical tables have been 

 made of their comparative frequency at morning, mid-day, and even- 

 ing. Although advanced age furnishes the largest number of cases, 

 apoplexy does occur even among children. Men are somewhat oftener 

 attacked than women. There is no such thing as an apoplectic con- 

 stitution, indicated by a short neck and broad shoulders. 



ANATOMICAL APPEARANCES. The distinction is made into capil- 

 lary haemorrhage and haemorrhagic clots, according as the bleeding 

 consists of numerous small, closely-packed effusions, or of a larger 

 quantity of blood. 



In capillary haemorrhages the cerebral substance appears dotted 

 with dark-red punctate extravasations at some point of variable size. 

 The cerebral substance between the small extravasations either re- 

 tains its normal color and consistence, or is colored yellow or reddish 

 to a variable extent by imbibition ; it is relaxed and moist, or, lastly, 

 it is broken down to a red pulp by the extravasation (red softening). 



Small haemorrhagic spots sometimes press the brain-filaments 

 apart ; but larger ones break up and become mixed with the brain- 

 substance. In the former case the effusion is sometimes elongated in 

 the direction of the filaments ; in the latter it is more roundish or irreg- 

 ular. In the former case the walls of the effusion are to some extent 

 smooth ; in the latter they oftener appear ragged, and are frequently 

 surrounded, for a space some lines thick, by a broken-down pulpy 

 brain-substance discolored with blood. The size of the clot varies 

 from that of a hemp-seed to that of the fist. If it be in the vicinity 



