ENCEPHALITIS. 133 



there is nausea and vomiting, and obstinate constipation of the 

 bowels. This last symptom is common in congestion, or inflamma- 

 tory affections of the brain. 



As the disease advances, all these symptoms are reversed ; the 

 morbid acuteness of the sensations changes into blindness and deaf- 

 ness ; the delirium passes into stupor, and gradually into coma. 

 Convulsions and difierent forms of paralysis ensue ; the countenance 

 is vacant or idiotic: the eye loses its lustre; the pupils become 

 dilated ; and occasionally there is strabismus. The respiration is 

 now irregular, occasionally stertorous, the articulation imperfect, 

 the pulse frequent and small, the limbs spasmodically convulsed or 

 paralytic ; there is retention of urine, and involuntary discharge of 

 the faeces. In - the still more advanced stage the countenance be- 

 comes pale and sunken, the pulse weak and irregular, the urine 

 passes off involuntarily, the skin becomes cold and clammy, the 

 coma more profound, and death soon closes the scene. 



Morbid appearances. — The inflamed part of the brain presents 

 different appearances, according to the time the disease has lasted. 

 When it is only of some days' duration, the white substance, and 

 still more perceptibly, the gray, exhibits a rosy, or slight red 

 colour; and in it we perceive several vascular filaments. The firm- 

 ness of the affected part is considerably diminished, and when cut 

 into, the surface of the incision presents a number of small red 

 points, which cannot be removed by ablution.* In a more advanced 

 stage of encephalitis, the brain is red, the vascular injection more 

 strongly marked, and the softening very considerable. Finally, in 

 some cases, the blood becomes so intimately mixed with the cerebral 

 substance, that its colour approaches that of the lees of wine, being 

 of a deep dusky red; there is no actual effusion of blood, except we 

 consider as such some small dots, about the size of a pin's head, 

 which we occasionally find in some particular points ; in such cases, 

 the brain is in a state of extreme ramoUissement. 



Should it happen that the inflammation passes into these stages 

 without causing death, then the part affected begins gradually to lose 

 its softness, and ultimately becomes more dense than in the natural 

 state ; it retains for some time its red colour, but finally changes to 

 a dusky yellow. 



The third stage of encephalitis is that of suppuration ; the red 

 colour gradually disappears, and the blood is replaced by a sero- 

 purulent fluid, which is infiltrated into the substance of the brain, 

 combines with it, and gives to it, according to the extent of the 

 admixture, a grayish, dull white, or yellowish-green colour. Some- 

 times the pus is found in small isolated spots ; at other times small 



* These small red spots differ from those of congestion, in which small drop^ 

 of blood reappear, as aoon as the first are wiped away. 



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