[Anatomy of the endolymphatic sac and its clinical significance]

Using 28 formalin fixed temporal bones and materials of 26 cases of endolymphatic surgery for menieres' disease, the location, vascular distribution and size of the endolyphatic sac (ELS) were investigated. ELS were measured with surgical microscope in all the cadaver specimen with a mean length of 6.9393 +/- 2.0429 mm and mean width of 5.8821 +/-1.6522 mm. All the specimens showed no clear capillary distribution. Only in 24 of the 26 ELS surgeries for Menieres' disease the ELS were found. The mean length was 6.8125 +/- 2.2449 mm, the mean width 5.6666 +/- 1.5084 mm and the vascular distribution was unclear in 29% of the cases. It was found that the ELS usually located at the Donaldson line, and moved downward in the under-developed mastoid with smaller size.