A handbook of diseases of the nose and nasopharynx / by James B. Ball.

  • Ball, James B. (James Barry), 1849-1926.
Date:
1890
Catalogue details

Licence: Public Domain Mark

Credit: A handbook of diseases of the nose and nasopharynx / by James B. Ball. Source: Wellcome Collection.

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    ■whicli frequently deviates to one side or the other. The cavity varies in size, and in some persons is altogether absent, and the sinuses on the two sides are usually un- symmetrical. The frontal sinus communicates with the nose by a canal which leads from the floor of the sinus, into the upper end of the infundibulum. The situation of this canal, and the fact that the mucous membrane around the orifice into the nose is closely aj)plied to the bone, favours the escape of fluid from the sinus. The Sphenoidal Sinus is situated at the posterior part of the roof of the nasal fossa in the body of the sphenoid. Its size varies much. It is separated from its fellow by a thin septum, which is often incomplete, and deviates to one side or the other. Sometimes it is subdivided into upper and lower compartments by prominent ridges of bone. It communi- cates with the nose by a fair-sized opening near the roof of the sinus, and behind the superior turbinate body. The Ethmoidal Sinuses, or Cells, are disposed roand the lateral circumference of the ethmoid, the spaces being com- pleted by the surrounding bones, viz., the frontal, sphenoid, lachrymal, inferior maxillary and palate bones. These cells vary in size and number. They communicate with one another, and are divided into anterior, middle, and posterior ethmoidal cells. The anterior cells open into the middle meatus behind the opening of the frontal canal, and the middle and posterior cells open into the superior meatus. The mucous membrane, Hning the various air spaces, is continuous with that of the nose, but is thinner and less vascular. Its deeper layer is everywhere closely united to the bone, of which it forms the periosteum, and its surface is covered throughout with columnar cihated epithehum. The mucous membrane of the maxiUary sinus is thicker than that of the others, and contains a moderate number of tubular and acinous glands. The frontal and sphenoidal smus, and the anterior ethmoidal cells, contain a few sparsely distributed glands. ^