
Ebook: Cholesteatoma and Anterior Tympanotomy
Author: Tamotsu Morimitsu M.D. (auth.)
- Tags: Otorhinolaryngology
- Year: 1997
- Publisher: Springer Tokyo
- Edition: 1
- Language: English
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Acquired aural cholesteatoma poses a unique procedural dilemma with regard to pathogenetic research and theory building. Because cholesteatoma spontane ously occurs only in the poorly pneumatized human ear, its pathogenesis is specific to humans. Nonetheless, because of the ethical questions surrounding human experimentation, pathogenetic study has almost exclusively involved nonhuman subjects. Indeed, attempts have failed in almost all animal expe riments except with the gerbil, and even here experimental designs have been improbable compared with human cholesteatoma. Cholesteatoma in the gerbil is useful, therefore, only for the study of pathology and not for human pathogenesis. I hold that the pathogenesis of cholesteatoma will be understood by studying the cholesteatomatous ear, that is, the malpneumatized ear of the human. The anatomical difference between the normal and malpneumatized ear is a probable cause of cholesteatoma. This difference may be found clinically in facial nerve decompression and cholesteatoma surgery, as, for example, facial nerve palsy occurs usually in the normal, well-pneumatized ear. Of course, conventional animal experimentation will not confirm this clinical difference since there is no ideal animal model for the poorly pneumatized human ear. Present surgical techniques for cholesteatoma vary greatly according to indi vidual otosurgeon's opinion. The most extreme difference of opinion is focused on whether to remove the external ear canal wall. Normally, the best option would be not to remove the canal wall if cholesteatoma recurrence can be prevented. Simply put, recurrence of cholesteatoma comes about when its cause has not been removed during primary surgery.
The pathogenesis of acquired aural cholesteatoma has presented a unique procedural dilemma for the researcher. Although the condition occurs only in humans, virtually all pathogenetic research has been conducted on nonhuman subjects. The results thus obtained have been of limited usefulness. The groundbreaking procedures presented in this volume now reveal that the pathogenesis of cholesteatoma is to be found by studying the malpneumatized ear in humans. The anatomical difference between the normal and malpneumatized ear is shown to be the probable cause of cholesteatoma. Conventional treatment focuses on removal of the lesion rather than improving intratympanic ventilation. As a result, recurrence of the condition is not unusual. With anterior tympanotomy, a new surgical technique developed by the author, recurrence rates have been significantly reduced, and the pathogenesis of cholesteatoma has been greatly clarified. Clearly stated procedures, with illustrations, elucidate techniques for successful cholesteatoma operation leaving the ear canal intact and reducing recurrence. The book is a valuable source to all those in the fields of otorhinolaryngology and audiology, and to surgeons and researchers concerned with cholesteatoma.