1 1 



THE METHOD OF MAKING POST-MORTEM EXAMINATIONS. 



the blood-vessels, miimte aneurisms, areas of degeneration, and rup- 

 tures. For this purpose it may be necessary to allow a stream of water 

 to run over the affected portion, so as to wash out the brain substance 

 and expose the vessels. In some cases the blood-vessels are best exposed 

 by macerating the brain tissue at the seat of the lesion for some hours in 

 water, and then washing out the brain substance under the faucet. 



While the above mode of dissecting the brain gives a very complete 

 view of the seat and extent of lesions in general, when a more exact 

 localization of lesions with a microscopic examination- is to be made, the 

 following -called Meyuert's method is a better method of opening the 

 brain: 



After completing the external examination, as detailed above, the 

 brain is laid on its vertex, the cerebellar end toward the operator. The 



cerebellum is raised by the 

 fingers of the left hand, and 

 the pia cut through along 

 the sides of the corpora 

 quadrigemina, around the 

 crura and along the inner 

 margins of the temporal 

 lobes, to the middle cerebral 

 artery on both sides (Fig. 4). 

 Then, raising the temporal 

 lobes, in turn, by their 

 apices, the pia is cut through 

 along the course of the mid- 

 dle cerebral artery into the 

 Sylvian fissure, and along 

 the course of its posterior 

 branch to its end. Now, 

 drawing the temporal lobes 

 one after the other upward 

 and outward, their junction 

 with the base is cut, the 



knife being held horizontally so as not to injure the basal ganglia, until 

 the descending horn is opened. The point of the knife being in the 

 descending horn, the incision through the brain substance then passes 

 outward and backward well into the posterior horn, thus partially sever- 

 ing, at the lateral surface of the brain, the junction of the occipital and 

 temporal lobes. The temporal lobes are then turned outward and back- 

 ward (Fig. 4). 



The operculum is now pulled well outward, completely exposing the 

 island of Eeil, and a slightly curved transverse incision is made, deep 

 enough to pass into the anterior horns of the ventricles, connecting the 

 anterior sulci of the island of Eeil (Fig. 4, A, B). 



Now raising the cerebellum and inserting 'the point of the knife into 

 the ventricle, with short incisions from within outward, cut through the 



FIG. 4,-ScHEMATic PICTURE OF BRAIN, SHOWING THE METH- 

 OD OF DISSECTION FROM THE BASE (Meynert's method). 

 E and F, Temporal lobes turned backward and outward; A 

 B, A C, B D, line of incision to remove basal piece. 



