Robert Froriep (1804-1861) and his seven otologic copperplate engravings: survey of otology at the beginning of the 19th century.

Robert Froriep published 487 Chirurgischen Kupfertafeln (surgical copperplate engravings). Seven of them, entitled Morbi aurium, are related to otology. They concern catheterization and injection of eustachian tube, surgery of the external auditory canal, anatomic relations of the different parts of the ear and perforation of the tympanic membrane, examination and cleaning of the external auditory canal, examination and perforation of the tympanic membrane, catheterization and injection of the eustachian tube, and again, injection through the eustachian tube. The aim of this study is to present these engravings and their correlations with the original related otologic publications. They provide a very good insight into the different instruments used in otology and their modifications in the first part of the 19th century.