MODULE 1
THE SKULL
- - We show you five views of the skull.
----- Figure 1-1. This lateral view simply shows the 6 bones that contribute to the surface of the cranial cavity. Of course, what we really care about is the relationship of these bones to the brain. If a penetrating wound passed through a given part of the temporal bone, for example, what region of the brain would it damage? To get some idea of the answer, look at the next view.
----- Figure 1-2. Now, we look right through the skull to get a lateral view of the brain, within the cranial cavity.
----- Figure 1-3. Here, the skull has been cut in the mid-sagittal plane, and we are within the cranial cavity, looking laterally. Line drawings of this sort do a poor job of conveying the 3-dimensional aspects of this complex space, so be sure to compare this view with an actual skull. Note the close relationship of the frontal and sphenoid sinuses to the interior of the cranial cavity.
----- Figure 1-4. In this view we look down at the floor of the cranial cavity. On the right, some of the obvious landmarks are labeled. On the left, we have tried to introduce you to the concept of the three cranial fossae. These terms are frequently used, clinically, to describe different regions within the cranial cavity. See Blumenfeld Figure 5.4 for a good 3-D view of the fossae that also shows how the brain fits into these spaces.
----- Figure 1-5. This view simply shows the major openings in the skull. When we take up the cranial nerves, later on, you will want to be able to say which nerves or structures pass through each of these openings. We propose to skip this detail for now, but if you want to look ahead, see Blumenfeld pages 464-6, Figure 12.3 and Table 12.2.