手術的な視角, 視野からみた副鼻腔形態のレ線学的研究

晒頭蓋のレ線像より検討せる篩骨洞および最後部副鼻腔への手術ルートについて

抄録

Two serious complications associated with radical operation of chronic disorders of the paranasal sinuses are intracranial damage and injury to the optic nerve.
The use of antibiotics has lessened the dangers of intracranial complications but injury of the optic nerve is still a matter of grave consequence.
In view of the seriousness of such complications, any means by which damage to these areas during operation could be avoided or lessened would be highly desirable.
It was therefore considered worthwhile to evaluated the various routes for operation of the ethmoid cells as the angle of vision and the field of exposure provided by the different routes would influence the execution of the surgical procedure and help in avoiding damage to the above structures.
Skulls of Japanese with intact bony structures of the face, consisting of 100 males and females each, were procured for this study.
Using the wire ligatures employed by dentists to fasten artificial crowns, wire coils conforming in shape, length and diameter to the optic foramen in each of the skulls were made and inserted into the canals.
Care was taken so that the ends of the metal coils did not project the orbital fossa or the cranial cavity.
In a similar manner, wire coils were inserted from the anterior and posterior ethmoidal foramen in the inner wall of the orbit, and landmarks were placed at the anterior nasal spine, foramen of the infra-orbital canal and rhinion.
Projections were made in the lateral, posterior-anterior and axial directions.
For the posterior-anterior porjection, Gonda's method of nasion-inion projection in which the central bean of X-rays passes in the direction of the inion through the nasion was employed. The axial projection in this study was in the direction parallel to the cribriform plate and perpendicular to the line connecting the inion and nasaion, the center of the beam passing through the hypophysis. Each picture was taken under identical conditions.
In some instances, projections of the optic foramen were also taken.
Operative Routes Evaluated on the Basis of Roentgenologic Study.
Many methods have been described for operation of paranasal sinusitis but they can be roughly divided into 3 maintypes according to the route of approach to the ethmoid cells.
The visual angle and field of exposure afforded by these 3 main routes, that is, the intranasal, extranasal and intraoral routes, were studied on the basis of measurements taken on the X-ray film of the skull specimens.
The purpose of the measurements taken on the X-ray films of the skulls was to provide numerical values for comparison of the extent of exposure afforded by the different routes of approach to the ethmoid cells.
Using X-ray films taken of skull of Japanese in 3 directions, measurements of the visual angle and field obtained with various operative sinus were taken to determine the suitbility of the different approaches.
Numerical values were obtained demonstrating the adventages of the intranasal route. It was also shown that the generally employed approach through the maxillary sinus for operation of the ethmoid cells was unsuitable when pneumatization of the ethmoid cells was poor as the visual field and angle needed for operation were unattainable and blind angles existed with this route.
Because of the danger of side injuries to the orbital plate of the ethmoid bone or potic nerve canal when this route is employed, it should be combined with one of the other approaches.
In other words, it is emphasized that in operation of the ethmoid sinus the route through the maxillary sinus should be employed only as an auxiliary route to other methods of approach.