Velpeau's Anatomy of regions / translated from the French by Henry Hancock.

  • Velpeau, A. (Alfred), 1795-1867.
Date:
1838
Catalogue details

Licence: Public Domain Mark

Credit: Velpeau's Anatomy of regions / translated from the French by Henry Hancock. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    is a vein situated in its substance; consequently perforation of the cranium at this point may cause considerable hemorrhage. Internally, corresponding to the median line, is the nasal promi- nence, more developed in adults and old men than in women and children; thus, in the latter the forehead is more uniform, and the root of the nose less sunken. An oblique fissure from below, upwards and outwards, separates it from the supra-orbital arch. The superciliary prominence forms the anterior wall of the frontal sinuses. As these sinuses are invested by a mem- brane which communicates with the nares, muco-puriform or other matter may by chance pass from the nose through an accidental opening in the forehead, and lead to the belief that it flows from the cranium. Another mistake may also occur, from discharge of pus, possessing the character of brainy mat- ter, from the sinus into the nose. From its communication with the nasal fossae, and the character of its secretions, wounds and othqr diseases perforating the anterior wall commonly give rise to fistulae, which are with difficulty cured. In consequence of the unequal separation of the two lamellae of the frontal sinuses, we should, as far as possible, avoid tre- phining over them, as the crown of the instrument may wound the meninges, or the brain itself, before the perforation of the bone is completed; nevertheless, in cases of necessity, the cra- nium may be perforated in this situation, without injury to its membranes, by taking the precaution of sawing the first bony layer with an instrument having a larger crown, and the second with a smaller, as was the practice of M. Larrey. We should also note, with regard to the trephine, that, in some instances, the frontal sinuses extend as far as the external orbital pro- cesses, or, posteriorly and superiorly, as far as the parietal bone, whilst in others they are wanting. These dispositions prevent a correct judgment being formed of the size of the anterior portions of the brain by the exterior of the cranium. When fluids collect or tumours are developed in these sinuses, their posterior lamella, being the thinnest, yields first, quickly causing pressure on the brain. Above the preceding prominences the frontal bone presents a groove, corresponding to the cutaneous depression mentioned at the commencement; more superiorly is remarked the frontal eminence, more or less prominent, and depending upon the degree of convexity or thickness of the bone itself. It may become depressed in old age by the absorption of the diploe, from disease or otherwise. Relative position.—In consequence of this arrangement we find, from before backwards. 1. The skin. 2. A dense cellular adipose layer, enclosing the principal vessels. 3. The orbicularis palpebrarum, corrugator supercilii, and