[Measurements of the tympanic cavity]

The angle between the annulus fibrocartilaginous and the superior crest of the petrous bone was measured with 14 (10 to 19) degrees. The height of the annulus was in our material 10.04 mm, the width 9.45 mm. Measured were also the length of the plicae malleares and the height of the recessus membrane tympani anterior, posterior et superior with (2.5, 3.0 and 1.5 mm). In about 74%, the chorda tympani was imbedded in different zones of the plicae malleares. Its entrance and exit areas, the length of its intratympanal course and its width were measured. Included are also values of the ligaments of the otic ossicles, measurements of the ostium tympanicum tubae auditivae, of the epitympanic recess, the aditus ad antrum, and the antrum mastoideum. The eminentia pyramidalis, the sinus posterior and the sinus tympani, ponticuli and subicula, the fossula fenestrae cochleae and the fenestra cochleae, the fenestra vestibuli and prominences of the facial canal in the lateral semicircular canal have been researched and measured. Also the tympanic nerve and its course on the promontorium have been estimated.