706 



SOFTENING AND INDURATION. 



the state of the fluids of the tissue, and the 

 presence of effused or infiltrated matters, it 

 may be bright or dark red, grey, yellow, and 

 sometimes almost black. 



Induration presents several degrees of re- 

 sistance to pressure or to the knife ; much 

 depends on the ordinary cohesion of the af- 

 fected organ. Generally speaking, the first 

 degree is characterised by a slight increase in 

 the resistance to pressure ; the second finds 

 the tissue denser, cutting with a cracking 

 noise ; and the third comprehends increased 

 cohesion, amounting to a cartilaginous or bony 

 hardness. 



Softening of the brain may be ascribed to 

 inflammatory action, or to a defective state of 

 the circulating apparatus of the organ ; it may 

 be an effect of a defective or perverted state 

 of the body generally, and it is frequently 

 caused by post mortem agencies. Now these 

 four varieties of softening, although, as re- 

 gards their external appearances they have 

 much in common, differ considerably from 

 each other, each having peculiar attributes. 

 The first and second varieties are generally 

 found in the most, and the third in the least, 

 vascular parts of the brain. Post mortem 

 softening occurs, for the most part, in the 

 immediate neighbourhood of the ventricles, is 

 usually very diffused, is found on both sides 

 at once, and is, of course, never preceded by 

 symptoms. 



Softening of the brain may be partial or 

 general, and may present various degrees: 

 the least change of consistence is only to be 

 recognised by the microscope ; in a more ad- 

 vanced degree the softening is obvious to the 

 unassisted senses, at first to the touch and 

 then to the eye, the diseased part being pul- 

 taceous, and readily removed by a stream of 

 water, a cavity surrounded by healthy struc- 

 ture being made evident. 



In a more advanced degree still, the cere- 

 bral substance instead of being pultaceous is 

 quite diffluent, and occasionally a perfect so- 

 lution of continuity is found. The softened 

 portion of brain presents various alterations 

 of colour. In inflammatory softening, the 

 colour mainly depends upon the previous 

 quantity of blood in the part; it may be of a 

 deep red colour, with or without effused clots 

 of blood, and frequently merges at the edges 

 into at first a deep, and then a pale, yellow 

 colour. Sometimes the yellow colour is 

 central and the reddened portion external, 

 resembling a collection of pus, so much so 

 that Lallemand described it as such. 



A dull red ochre colour with more or less 

 hardening in the neighbouring structure, is 

 indicative of chronic disease of long standing; 

 as is also a chalky milk appearance, and a 

 bright vermilion, of a recent effusion of blood 

 into a previously softened part. In com- 

 mencing softening, a diffused blush, with or 

 without spots of blood, is generally found. 

 A deep grey colour and fawn and dirty white 

 tints accompany inflammatory softening, but 

 much more frequently that which is produced 

 by a deficient supply of blood. 



No alteration of colour takes place in post- 

 mortem softening. 



These distinctions of colour indicate no 

 essential differences, as far as structure is 

 concerned, for all coloured softenings may 

 present the same histological characters. As a 

 general rule, the red varieties are indicative 

 of acute inflammation, yellow of subacute, and 

 white or grey of deficient nutrition of the 

 affected part ; but this rule is by no means 

 invariable. 



Universal softening of the brain, accom- 

 panied by a smell of sulphuretted hydrogen, is 

 jfound in children suffering from general de- 

 bility, and occasionally in infants stricken with 

 induration of the subcutaneous cellular tissue. 



Softening from a defective state of the cir- 

 culatory apparatus is found, for the most 

 part, in persons advanced in life, and consti- 

 tutes what is termed white softening. It de- 

 pends on the presence of osseous, cartila- 

 ginous, or atherornatous matter in the walls 

 of the arteries, nearly or quite blocking up 

 their entire caliber, and affecting vessels of 

 all sizes. It may supervene upon occlusion 

 of the common carotid from ligature, and, 

 indeed, upon any circumstance retarding or 

 diminishing the quantity of blood to the brain ; 

 intense inflammation may disorganise the ves- 

 sels, carrying blood to a remote portion of 

 the brain, and thus cause softening ; or a 

 severe blow, or the presence of a tumor of 

 greater or less density and magnitude, may 

 act in the same manner. 



The very fact of adventitious products 

 being found within the arteries, hints at a 

 perverted state of the brain and system gene- 

 rally ; absorption does not progress in the 

 diseased portions of the brain, which, having 

 lost their supply of blood, are in a state ana- 

 logous to that of an extremity attacked with 

 gangrena senilis. 



The softening of the brain which is pro- 

 duced by post mortem agencies is of very 

 frequent occurrence. It may exist alone, or 

 may complicate the other varieties, and is 

 caused by the decomposition natural to or- 

 ganised bodies after death, or by the infil- 

 trating action of fluids, which, either during 

 life or in the agony of death, were effused into 

 the ventricular cavities, and sub-arachnoid 

 spaces. 



Softening of the spinal cord is of not un- 

 common occurrence. It presents the same cha- 

 racters as those pertaining to the like affec- 

 tion of the brain, is produced by the same 

 causes, and offers the same pathological cha- 

 racters. Softening of the whole cord may 

 occur, but most frequently parts of it only 

 are affected ; it is found softened most fre- 

 quently in the lumbar region, and not unfre- 

 quently in the cervical. 



Induration of the brain may be general or 

 partial, and presents three degrees of consist- 

 ence. In its first degree, the affected part is 

 nearly of the consistence of a brain which 

 has been left some time in dilute nitric acid ; 

 in the second degree, the indurated part is of 

 a cheesy, and in the third of a waxy, fibro- 



