TREPHINING OF THE FRONTAL SINUSES. 



31 



By studying Plates IV-X it will be seen that any collec- 

 tion of pus or other pathologic contents in the frontal sinus 

 at F would result in poor drainage so far as may be obtained 

 by trephining through the external wall only. The 

 drainage, whether the contents have formed within the 

 frontal sinus itself, or have entered it through the fenestrum, 

 FE, Plates V and VI, from the superior maxillary sinuses 

 should be completed by making an artificial communication 

 through the turbinated bone between the frontal sinus and 

 the nasal fossa at ST, Plates IV, V and XI. This is to be 

 accomplished by breaking through the thin walls of the 

 turbinated bone by means of a probe or other suitable instru- 

 ment and enlarging the opening sufficiently with the probe- 

 pointed bistoury or with the finger. In locating the exact 

 point for making this opening in the turbinated bone it is 

 advisable to pass a slightly curved heavy probe, a pair of 

 long curved uterine dressing forceps or some other slightly 

 curved and somewhat rigid instrument up the nostril to 

 the operative region and having an index finger in the 

 sinus against the median wall, the movements of the sound 

 can easily be felt and the wall be broken down either by 

 pushing the sound up into the sinus or thrusting the finger 

 downwards into the nasal passage. 



In order to prevent aspiration of pus, blood or other fluids 

 after the perforation of the highly vascular turbinated bone, 

 the animal must be allowed to get up immediately or if 

 under general anaesthesia a trachea tube should be inserted 

 sufficiently early to avoid danger. 



Thread a long probe with a heavy suture about 75 cm. 

 long and inserting it through the trephine opening into the 

 nasal passage draw it out through the nostril and removing 

 the probe, attach a strip of gauze 75 cm. long to one end of 

 the suture, draw it out through the nostril and tie the ends 

 together on the side of the face to prevent dislodgement. 

 Retain the gauze in position for about forty-eight hours to 



