伴有骨导下降的中耳疾病手术效果分析

Postoperative hearing results of chronic middle ear diseases with bone conduction loss

目的探讨慢性中耳炎(胆脂瘤)伴有骨导下降患者经手术治疗后骨导听力的改善及其生理基础,并与耳硬化症术后“卡哈氏”切迹的变化进行对比分析。方法病例分二组,一是本院耳硬化症手术有一年以上完整听力随访资料的42例(57耳),平均年龄46.74岁(15～71岁),男8例(12耳),女34例(45耳)。二是同期中耳炎(含鼓室硬化、胆脂瘤、粘连性中耳炎)行听力重建并有一年以上随访资料者182例(200耳),平均年龄43.92岁(15～72岁),男79例(83耳),女103例(117耳)。统计二组术后骨导听力改善(至少一个频率减少10dB以上)的耳数和百分比,进行卡方统计分析。结果镫骨手术组57耳术后有13耳(22%)、中耳炎组200耳中有51耳(25.5%)符合条件。卡方检验,!2=0.172<!20.05=3.8416,故P>0.05,2组差异没有显示显著性意义。2个典型病例术后骨导明显改善。结论耳病变由于改变了振动频率,或增加了质量负荷,都可以影响骨导;中耳炎毒素也可以使内耳水肿,细胞变性甚至坏死。前者随着中耳病变解除,骨导可以恢复;后者需要尽早治疗,部分可能挽救。

Objective The aim of this study was to compare the postoperative hearing results of patients with chronic otitis media complicated by bone conduction deterioration versus those with otosclerosis, with emphasis on the bone conduction threshold improvement （i.e., improvement of Carhart notch in otosclerotic ears）. Methods Two groups of patients were enrolled in the study. One group consisted of 42 patients with otosclerosis （12 ears of 8 male patients and 45 ears of 34 female patients, a total of 57 ears） with a mean age of 46.74 （15 - 71） years. Another group consisted of 182 patients （83 ears of 79 male patients and 117 ears of 103 female patients, a total of 200 ears） with chronic middle ear diseases （including chronic otitis media, tympanosclerosis, cholesteatoma and adhesive otitis media） with a mean age of 43.92 （15-72） years. All the patients underwent stapedotomy or tympanoplasty, correspondingly, and were followed up for more than one year and adequate postoperative hearing data were obtained, Bone conduction threshold improvement, in at least one frequence, of 10 dB or more was recorded and the chi-square test was used for statistical analysis, Results Of 57 ears undergoing stapedotomy and 200 ears undergoing tympanoplasty the bone-conduction improvement was achieved in 13 ears （22.8%） and 51 ears （25,5%）, respectively, The chi-square test obtained X^2 value of 0,172 〈 x^2 = 3.8416, P 〉 0.05, The results showed no significant difference between the groups. Two typical otitis media cases who underwent significant postoperative bone conduction improvement were described, Conclusion Middle ear diseases can affect bone conduction as they alter the resonant frequency of the ossicles or increase their mass loading, The effects, however, are reversible in case the lesions be relieved. On the other hand, toxic substances or inflammatory mediaters during otitis media may induce inner ear toxicity and cause a actual sensorineural hearing loss, Therefore, the middle ear inflammation must be diminished as early as possible so that the bone conduction hearing may be protected to some degress from toxicity.