抄録
Endonasal sinusectomy is one of the most useful operations for treatment of chronic sinusitis. However, severe complications may be associated with this procedure during operation.
That is, injury to the roof of the ethmoid sinus, which is the base of the skull itself.
The possible complications due to the injury will be CSF rhinorrhea or intracranial infections. A previous study by the author about the incidence of such complications revealed that injury to the base of the skull occurred in 0.15% and acute meningitis in 0.01% in a total of 450, 000 operations.
In the present study a close observation of 17 (34 sides) skull spea'mens by the operating microscope revealed five major dangerous areas in the roof of the ethmoid sinus where anatomical structures present unusal vulnerability to injury during operation because of bony dehiscence or defects.
The five dangerous areas are 1) the medial cranial wall of the ethmoid sinus, 2) the area about the anterior ethomoid nerve foramen, 3) the site of origin of the middle turbinate bone 4) the antero-lateral aspect of the ethmoid roof and 5) the area about the posterior ethmoid nerve foramen.
The author found frequent bony dehiscences in the above sites where the submucous connective tissue is in direct contact with the dura mater and also unusual structure of intimate adhesions between the bony roof and connective tissue of the dura mater. Any injury to the bony roof of the ethmoid sinus in such areas would inevitably cause injury to the dura mater and would be followed by CSF rhinorrhea or intracranial infections. The author stressed that utmost care should be used in operation of the above 5 sites.
