The periosteum is carefully peeled off the nasal process of the superior maxilla, and turned down from the inner third of the supra-orbital arch, exposing a triangular area of bone. The periosteum must be carefully preserved over the inner part, to avoid the risk of necrosis of the arch, which is converted into a bridge, the ‘Killian bridge’, by the opening in bone below and above it.
Fig. 338. Periosteal Elevators.
Fig. 339. Killian’s Triangular Curved Chisel.
The upper flap of soft parts, with the periosteum, is well retracted up on to the forehead. The radiograph will have given an idea of the extent to which the front wall of the sinus must be laid bare. With a chisel and hammer the sinus is opened at its inner extremity. A good plan is to employ Killian’s triangular curved chisel (Fig. 339) and to cut a trench in the bone along the upper margin of the bridge. This trench is gradually deepened at the inner end until the sinus is entered. The entry is generally announced by the bulging upwards of the blue, polypoid, pyogenic membrane into which the thin white delicate mucosa of the cavity has been converted. The anterior wall is now completely removed with hammer, chisel, and forceps. Those of Lombard, Horsley, Hajek (Fig. 341), Jansen, Citelli (Fig. 340), or similar models enable us to bevel down the margins of the cavity carefully as it slopes up on to the forehead.
| Fig. 340. Citelli’s Bone-forceps. |
Fig. 341. Hajek’s Bone-forceps. |
The pyogenic membrane is now carefully plucked away with a pair of Grünwald’s forceps. I never find it necessary to curette the cavity, which must always be a risky proceeding. Small pledgets of ribbon gauze, if gently rubbed along the surface and into the corners, will detach every scrap of diseased mucosa.
The septum separating the two frontal sinuses may be found to be defective. The opening through the eyebrow on one side may open into a cavity which communicates only with the nasal cavity of the opposite side—one sinus being very large and extending far beyond the middle line, while the other is quite small. Or only one frontal cavity may be present. An extensive acquaintance with the surgical anatomy of the region is required to prepare the surgeon for encountering these and other irregularities, and the systematic use of radiography will prevent him from being taken by surprise.
