Retrospective Analysis Of 47 Cases Of Petrous Bone Cholesteatoma

ObjectiveTo explore the clinical manifestations,classifications,diagnosis,treatment strategies and prognostic factors of petrous bone cholesteatoma,and to summarize the treatment experience of this disease.MethodsThe complete clinical information of 47 patients with petrous bone cholesteatoma in department of ENT of our Hospital from June,2005 to September,2016 was analyzed retrospectively,including clinical manifestation,Sanna classification,management,facial nerve and hearing function,complication and recurrence.All the patients were pathologically diagnosed.Fisher exact test was adopted to explore the correlation between the Sanna classification and hearing loss.To find the effects of different classifications on facial nerve function before and after surgery,Kruskal-Wallis test(also called H test)was used in this study.Furthermore,univariate and multivariate logistic regression analysis were used to determine the correlation between the post-operative facial nerve function and other prognostic factors,such as gender,age,severity of facial nerve injury,duration of facial paralysis and so on.ResultsOut of the 47 patients,13(27.7%)were diagnosed as congenital petrous bone cholesteatoma and the others(34 cases,72.3%)were acquired.The most common initial symptoms were otorrhea,hearing loss and facial nerve paralysis.Using Sanna classification system,66.0%(31 cases)were supralabyrinthine,4.3%(2 cases)infralabyrinthine,4.3%(2 cases)infralabyrinthine-apical,12.8%(6 cases)massive,and 12.8%(6 cases)apical.There were different surgical approaches involving the management of petrous bone cholesteatoma,such as translabyrinthine/transcochlear approach(34 cases),enlarged mastoidectomy(7 cases),middle fossa approach(4 cases),middle fossa+transmostoid(1 case)and infratemporal fossa approach B+transcochlear approach(1 case).The statistic analysis revealed that hearing preservation after surgery was unrelated to the Sanna classification.After the surgery,6 patients presented with House-Brackmann grade ?,4 with grade ?,4 with grade ?,8 with grade ?,10 with grade ?,and 15 with grade ?.Moreover,there were no statistically significant differences in postoperative House-Brackmann score among Sanna classes.The severity of facial nerve injury had a significant influence on the postoperative facial nerve function preservation.According to the results of follow-up,recurrence rate was 8.5%(4 cases).Conclusion1.For the deep position of the lesions and atypical clinical feature,it is difficult to diagnosis the petrous bone cholesteatoma.However,early diagnosis and treatment is vital for this type of patients.2.The Sanna classification system is scientific and efficient for petrous bone cholesteatoma and it can provide clinical guidance for choosing surgical approach.However,whether this system can predict the function preservation before and after surgery is still uncertain.3.The preoperative hearing function has a close correlation with the erosion of cochlea,while the postoperative hearing function is hard to preserve generally.The severity of facial nerve lesion is the independent influencing factor of the postoperative facial function.4.To choose the best surgical approach,Sanna classification and hearing function should be taken into consideration.The primary object is to clear cholesteatoma completely and the function preservation should be secondary.We recommend the cavity obliteration after the choleateatoma removal for the low complication occurrence.