The repetition of the operation of trephining is now never adopted, as was proposed by Lassus, and performed on the Count of Nassau in King Wil liam's wars no less than twenty-seven times; but it may be done on any part of the cranium within reach; the superior longitudinal sinus and other objects forming no interdicted points, as in the days of the ancients, but only points of caution. On some rare occasions, blood and even pus have been found effused in the diploe. See J. Bell's Principles of Surgery, vol. ii. p. 431. After' the operation of trepaning the patient should be bled and treated antiphlogistically, and for months af terwards he ought to avoid all exciting causes. The flaps of the integuments are to be put down and managed lightly with simple dressings. Sup puration of the dura mater occurs in caries of the frontal and parietal bones in corona veneris, and even sometimes spontaneously, as exemplified in the case detailed in Abernethy's Surgical Works, vol. ii. p. 108. Blows or contusions of the cranium produce sometimes only an exfoliation of the bone, which, though slow in its progress, never is free from danger. It has been proposed to replace the circular disc, but this is perfectly inadmissible in disease.
After the operation of trepaning, phrenitis is a common occurrence, and hence the reason of di recting bloodletting after this operation on all oc casions; for the nature and treatment of this affec tion, the reader is referred to the article Mentc!NE, p. 720; and we have only to observe that we prefer arteriotomy to phlebotomy, apply cold cloths to the head and warmth to the feet, blisters to the nape of the neck, but never to the crown of the head, and that it is very difficult to produce syn cope in affections of the brain. Acute inflamma tion of the brain, if neglected, generally soon ter minates fatally, either by general effusion between the arachnoicl membrane, and pia mater, and into the ventricles; or by effusion of coagulable lymph, or suppuration of the tuniea arachnoides and pia mater. But eases arc detailed or its terminating in blood and even gangrene.
After this operation, also, if the dura mater be injured, a fungous growth of the brain sometimes shoots forth, termed hernia, or fungus cerebri, which excrescence depends both upon a healthy and diseased condition of the brain; springing up with surprising rapidity in the latter state of this organ. This fungous growth is also consequent on fracture of the cranium with depression, wound ing the Jura matey, or on ulceration of the dura matey, or on concussion of the brain. For an ex ample of hernia cerebri arising in a healthy con dition of the brain, the reader is referred to Hey's Pract. Observ. in Surgery, case of Boy "Popham; and for cases depending on a diseased condition of the organ, to Hill's Cases in Surgery, J. Bell's Principles of Surgery; Abernethy's Surgical TVorks, Hennen's Military Surgery, and Thomson's Report on Belgium. In the healthy condition, the pia ma tey is wounded, and the tumour has the natural appearance of the brain, merely more vascular, and is evidently analogous to fungous or exuberant granulations of other parts of the body; while in the diseased, it is generally of a grayish colour with coagulated blood, and a turbid serous fluid around, and strangulated at its root, and resembles fungus hmmatodes of other textures. In the latter,
it is preceded and accompanied by more or less stupor, slowness of pulse, dilatation of the pupils, slight strabismus, and paralytic affection of the mouth, the symptoms in many cases precisely re sembling those of compressed brain; and in some instances, by symptoms of inflamed membranes of the brain, and particularly delirium. The treat ment of this tumour by the authors referred to is very variable, but what we have found most bene ficial is the free use of the lancet to remove the cause, and whenever the fungus appears above the level of the surface of the brain, to pare it off with the scalpel, and apply the most light and gentle dressings possible; to evacuate any matter lodged beneath the tumour; to remove all cause of strangu lation at its root; to put the patient on low diet, in a darkened chamber, and to keep his bowels very open. If hemorrhage occur, exposure of the sur face to the air generally checks it, otherwise the actual cautery should be applied: the bleeding is generally more beneficial than injurious. In the fungus originating from a healthy state of the brain, low diet, open bowels, perfect rest and cutting off the luxuriant growth, almost always succeed; but if it continues to sprout forth, bloodletting should be adopted.
Compression of the brain may be produced by the effusion of matter, blood and water, or scrum; by the congestion of blood in the vessels, and by de pression of the hone. This state of the brain is in dicated by loss of sense and voluntary motion, the individual being unable to move a limb, being blind, deal, dumb, and without the faculty of smelling or tasting; a slow heavy pulse, stertorous breathing, and dilated pupils, because the fountain or centre of nervous energy is suspended in its function. The depression of the bone is always the result of ex ternal injury, and is of a greater or less extent, ac cording to the severity of the blow. Simple frac tures of the cr5.tium are in themselves productive of no evil, and occasionally take place on the oppo site side of the head to that where the blow was in flicted, and sometimes produce a circular fracture of the entire cranium, and are often the cause of hemorrhage and inflammation. When a fracture occurs in the base of the cranium, some of the blood vessels are generally wounded, producing extrava sation, that leads to fatal events, and not unfre quently blood issues from both the nostrils and ears. When the frontal sinuses arc simply fractured, and the nose blown, the air escapes into the cellular substance of the forehead, rendering it emphysem atous.