Objective To investigate the structure and function of cross-links on stereocilia of guinea pig outer hair cell (OHC). Method The ultrastructures of cross-links on stereocilia of guinea pig OHC were observed by scanning electron microscopy and tannic acid procedures. Results The side-links ran horizontally between OHC stereocilia. The stereocilia of the same and different row on each hair cell were joined by horizontally-running links. The side-links were observed in the first turn as well as the fourth turn. There were more side-links on the intact stereocilia than that on the disrupted arrangement. The side-links in the first turn and the fourth turn were more abundant than that in the second turn and the third turn. The side-links between stereocilia were spare if the stereocilia were separated. The number of side-links on stereocilia was proportional to the number of bulb-like structures on stereocilia. Conclusion The side-link is a kind of morphological structure on hair cells stereocilia of cochlea. The results suggest that cross-links play an important role in maintaining the structure and function of the hair cell stereocilia.

This paper presented the hereditary pattern of otosclerosis in families. Among 1500 cases there were 13 patients, belonging to 6 families, and 20 ears were surgically treated. There was often a marked similarity in clinical features of affected siblings within the same family.The clinical characteristics are as following: (1) The age at inset of hearing loss seems similar. There is a difference of 1 or 2 years in two families znc 3 to 10 years in the other four. (2) The side of first hearing loss is the same in affected individuals of 6 families. (3) The propositi are females in 5 families (83.3%). (4) Auditory curve of hearing loss is similar in 4 familiers, and different in the other two. (5) The footplate lesions are similar in macroscopic features, thin footplate in two fimalies and thick footplate in the other four.