[The relation between the morphological change of supratubal recess and otitis media].

OBJECTIVE: To observe the anatomic characteristics of supratubal recess and the morphological change of it in the sick ear. To investigate the relation between the morphological changes of supratubal recess and otitis media. METHOD: Using high resolution CT to observe and measure the supratubal recess of the normal ears and the ailing ones. RESULT: For the normal adults, the anteroposterior diameter of the supratubal recess is (3.83 +/- 1.28) mm, the vertical diameter (3.67 +/- 1.14) mm, the height (3.76 +/- 0.36) mm; and the length of the cog is (2.84 +/- 0.38) mm. The size of the supratubal recess showed no significant difference between left and right (P>0.05). There was no relationship between the size of the supratubal recess and pneumatization of mastoid cells (P>0.05). There was significant differences in size of the supratubal recess between normal ears and the ears with cholesteatoma (P<0.05), but there was no relationship between the size of the supratubal recess and pneumatization of mastoid cells (P>0.05) in the ears with cholesteatoma. There was no significant differences in size of the supratubal recess between normal ears and the ears with chronic otitis media (P>0.05). In the ears with cholesteatoma, 40% had osseous destruction in supratubal recess. CONCLUSION: For the normal adults, the size of the supratubal recess showed no significant difference between left and right, and there was no relationship between the size of the supratubal recess and pneumatization of mastoid cells. Anterior tympanic isthmus , posterior tympanic isthmus and supratubal recess which is the supplement of the formers constitute the air way between attic and mesotympanum. The supratubal recess of the cholesteatoma is smaller than the normal, when the eustachian tube dysfunction occurs, the air way in the middle ear would herein be affected, and cholesteatoma forms eventually. There was no significant differences in size of the supratubal recess between normal ears and ears with chronic otitis media, as in the clinic. The effect of the supratubal recess should be taken into account when we consider the pathogeny and treatment of the middle ear cholesteatoma.