ANATOMICAL RELATIONSHIPS BETWEEN POSITION OF THE SIGMOID SINUS AND REGIONAL MASTOID PNEUMATIZATION

In order to examine the relationship between the location of the sigmo id sinus (SS) and mastoid pneumatization, 25 adult temporal bones were dissected. Pneumatization was evaluated according to findings during dissections of three separate regions of the mastoid: i.e., the sinodu ral angle (SDA) area, inter-sinofacial area and mastoid apex. In addit ion, the SDA and distances between the SS and vertical portion of the facial nerve were measured at the second genu (G) of the facial nerve, the junction (J) of the nerve and digastric ridge and the midpoint be tween G and J. A good correlation was observed between pneumatization of the cells surrounding the SDA and the distance between the SS and f acial nerve at the mid-point of its vertical segment. However, pneumat ization of the inter-sinofacial air cell tract could not be correlated with this distance. A significant decrease in the values of the SDA w as found when the air cells surrounding the SDA were poorly pneumatize d. This study indicated a correlation between the position of the SS a nd pneumatization of the mastoid in the area of the SDA.