69 N. Y. Med. Record, vol. xvii. p. 617.
Considering the fact that cases with such marked and decisive symptoms as those last recorded have recovered, it is certainly the duty of the physician to prolong the life of his patient to the utmost, that absorption and condensation may go on as long as possible and collateral circulation be developed. Probably most physicians can recall cases of obscure cerebral disease going on to recovery contrary to all expectation, in which thrombosis furnishes an explanation quite as plausible as any other.
Softening of the Brain
is a name which it is yet too early to omit altogether from a systematic work, although in treating of it we have more to do with nomenclature and classification than with pathological anatomy. The phrase may be said to have both an anatomical and a clinical signification, which do not coincide at all points. Clinically and among the laity it is used to express various symptoms and groups of symptoms more or less referable to the brain, some of them connected with one and some with another lesion, and many purely functional—if the word may be used—or at any rate unconnected with any known or definite lesion.
Vertigo, dull headache, sleeplessness, or, on the other hand, drowsiness, failure of memory, failure of power of concentration, of steady application, mental depression, fatigue, and even slight aphasia or actual slight hemiplegia, may any of them be considered symptoms or forerunners of softening of the brain. As nearly as anything, the popular notion of this affection corresponds to general paralysis of the insane or senile dementia, or even mere exhaustion. Many of these symptoms may, of course, be connected with the real softening described as the result of embolism or thrombosis, but it is hardly necessary to say that a symptomatology based on these elements alone is either too vague or else too much like that of diseases already described to be considered useful as a separate clinical grouping.
On the anatomical side softening of the brain has had a definite meaning, and for many years a part of its pathology has been well known. A general softening of the whole brain, such as seems to be the condition supposed when the phrase is used, does not and cannot exist, since a vascular lesion sufficient to cause anæmic necrosis of the whole brain must cause death long before softening would have time to take place. Nearly all the works and reports on softening have been based upon cases such as are now referred to definite lesions of the blood-vessels; and a good idea of the change in nomenclature and pathological views may be obtained by noticing the dates given in the extensive literature of the subject in the Index Catalogue of the Surgeon-General's library, which are nearly all previous to 1860 or 1865.
Localized softening has already been described under the heads of hemorrhage, embolism, and thrombosis, venous and arterial. Whether it may occur from diseases of the cerebral vessels without actual occlusion is not certain, but, remembering the difficulty of detecting thrombi in minute vessels, and also the fact that it is not a great many years that occlusions have been systematically sought for at autopsies, it is better for the present to assume, in cases where softening is found in the usual form and the usual situations for the results of thrombosis and embolism, that one of these accidents is the cause, even if the actual point of occlusion is not found.
Softening may take place secondarily from tumors in the brain, and the name is also sometimes applied to a local encephalitis, which is an early stage of abscess. When, however, these various forms of disease are removed from the general heading of softening and referred to their proper pathological classes, there is a residuum in which the softening seems to be the primary affection, so far as the brain is concerned, though depending on other constitutional conditions.
In new-born infants softening of the brain, besides the rare cases in which it may be dependent on the same conditions which may cause it in the adult, is observed in two forms, as described by Parrot:70 A. White softening in multiple foci, dependent upon fatty degeneration, of which it constitutes the last stage, is found almost exclusively in the centres of the hemispheres. B. Red softening, which affects the same region, but more extensively, and is accompanied by hemorrhage into the lymphatic sheaths with rupture.
70 Arch. de Phys., 1873, p. 302.