PARTIAL ANAEMIA OF THE BRAIN. 209 



spheres, and the above-mentioned large ganglia lying in them, with 

 blood, are the ones that are most frequently closed by thromboses ; 

 and, even if the anaemia directly resulting from the obstruction, and 

 the consequent softening, do not extend to the corpus striatum and 

 optic thalamus, these parts will readily lose their functional power 

 from the collateral oedema about the point of softening, or from the 

 capillaries of the entire hemisphere being compressed by it. If a large 

 vessel be closed by a thrombosis originating from the walls, and grow- 

 ing slowly, or if numerous smaller arteries be closed one after the 

 other, the paralysis comes on slowly, and increases gradually. Cases 

 running this course are the most readily recognized; for, although 

 gradually-forming and slowly-progressing paralysis also occurs in many 

 other cerebral diseases, if this symptom arise in an old marasmic pa- 

 tient, who has had the previously-described symptoms, we must first 

 think of thrombosis of the cerebral vessels, and of the form of soften- 

 ing of the brain at present under consideration. While the symptoms 

 of paralysis, which are very often and unaccountably accompanied by 

 contractions of the paralyzed part, gradually increase and extend, the 

 patients become more apathetic, grow imbecile, pass their excrements 

 involuntarily, have bed-sores, and finally die of marasmus and coma. 

 The course is different when a large vessel or numerous small ones are 

 rapidly closed by thrombosis. In such cases hemiplegia occurs sud- 

 denly, and the symptoms may be very similar to or identical with those 

 of cerebral haemorrhage. This correspondence is easily explained. 

 In cerebral haemorrhages, also, most frequently, the corpus striatum 

 and thalamus are either broken up, or their functional activity is ar- 

 rested by the compression that capillaries of the whole hemisphere 

 suffer from large effusions. In cerebral haemorrhages also, hemiplegia 

 usually occurs suddenly. Moreover, ruptures of the cerebral arteries 

 usually occur in old persons, and are most frequently due to the same 

 disease of the vascular walls that generally induces thrombosis. We 

 shall not enumerate the symptoms given for a differential diagnosis, 

 and shall only refer to an assertion of JBamberger's, for which science 

 is indebted to such an undisputed authority on diagnosis. Bamberger 

 says that, in his notes, he finds seven cases where there was an error 

 of diagnosis, and the real state of affairs was only discovered at the 

 autopsy ; he considers it impossible to avoid this error, and says he 

 seldom ventures to make an absolute diagnosis of cerebral haemorrhage 

 from an apoplectic attack. 



Partial anaemia and necrosis of the brain due to embolism are 

 also almost always preceded by characteristic premonitory symp- 

 toms. But these are not brain-symptoms, as they were in the pre- 

 vious form of anaemia of the brain ; they are those of the diseases which 



