Six difficult petrous bone cholesteatoma patients will be demonstrated which are divided into two groups according to the surgical methods. Three of them were performed transmastoid endoscopic approach and another three cases infratemporal fossa approach Type B. All the six cases achieve satisfied outcomes with follow-up. All these six cases related with the apical area where we think would be better be eliminated through the infratemporal fossa approach Type B or transmastoid together with the endoscopy. The former one can acquire the best exposure by inferiorly disjoint the temporomandibular joint which do not cause subsequent mastication problems and have little influence on patients’ appearance. The latter one, with the advancement of the surgical instruments such as the endoscopic, can also realize the surgical purpose which means to radical eliminate the lesion especially that medially to the otic capsule. At the same time, endoscopic have obvious advantages of function preservation for specially cases.

In conclusion, we'd better focus more on the lesion and the way to reach to and radical removal of them and should not be limited by any approach. Exposure, radical exenteration, adequate exteriorization, we recommend, are the basic principles for the temporal bone and lateral skull base surgeries include the PBC surgery. Even with the help of endoscopy, a radical exteriorizated mastoid cavity is always required for a best exposure. With the development of the instruments and equipment, so manipulationmay be changed, the principle will be go on.