The human brain : histological and coarse methods of research : a manual for students and asylum medical officers / by W. Bevan Lewis.

  • Lewis, William Bevan, 1847-1929.
Date:
1882
Catalogue details

Licence: Public Domain Mark

Credit: The human brain : histological and coarse methods of research : a manual for students and asylum medical officers / by W. Bevan Lewis. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

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    noid, but also to the fact that the former membrane is attached to the surface by the prolongations of connective cells recog- nized as Deiter's corpuscles. These are by no means nume- rous in health, yet sufficiently so as to keep the pia mater in firm contact with the cortex. These cells are chiefly found in the neighbourhood of the vessels, where they enter the cortex from the pia mater, and both together they form an impediment to easy stripping. In cases of serous subarach- noid effusion, such as the one under consideration, the mem- branes have been floated up from the receding surface of the atrophic cortex, and the connections with Deiter's corpuscles have therefore been forced asunder. After noting fully the consistence of the brain according to the plan already given, a section was made exposing the centrum semi-ovale, and the following facts presented themselves :— 1st. The blanched aspect of the cortex and the absence of any reddish striation of the u.pper layers, such as is seen when the cortical vessels are full of blood. The hue of the cortex was ashy grey throughout, except in its most vascular zone, where perhaps the slightest warmth of tint was recognizable, but beyond this, nowhere did any blush suggest the presence of its extremely elaborate vascular apparatus. 2nd. The layers were individually very poorly differen- tiated. 3rd. The medulla was brilliant white, glistening, slightly reduced in consistence, and showed few or no puncta vas- culosa. We must bear in mind that the vessels of the meninges may be tortuous and turgid with blood whilst the minute vascular supply of the cortex is absolutely diminished, and the layers appear blanched and anaemic. To a certain extent this was the case in the brain we have under consideration. How this occurs (passive or active hyperaemia of the mem- branes associated with anaemia of the cortex) will be explained in our next section when speaking of hyperaemia of the brain. For the present let us mark well the fact that the vascular condition of the membranes is no index, as a rule, to the state of the cerebral substance. E