Lloyd Simon, Meerton Leah, Di Cuffa Riccardo, Lavy Jeremy, Graham John
Cochlear Implant Programme, Royal National Throat Nose and Ear Hospital, London, UK.
Cochlear Implants Int. 2007 Dec;8(4):203-10. doi: 10.1179/cim.2007.8.4.203.
Taste change is a well documented but under emphasised complication of middle ear surgery and is usually related to damage to the chorda tympani nerve (CTN). However, the taste outcomes following cochlear implantation have not been previously recorded. One hundred and forty one patients who had received cochlear implants between January 1997 and April 2006 were questioned using a postal survey regarding changes in the sense of taste following cochlear implantation. Sixty seven per cent of questionnaires were returned. Forty three patients (45%) experienced changes in taste following their surgery. Eighteen patients (19%) said that their symptoms had not resolved by the end of the follow up period (mean 51 months). CTN division produced taste change in 86%. Fifty per cent of patients who had CTN preservation developed taste change, presumably related to occult trauma to the nerve. The difference in the number of patients describing taste change in the two groups was statistically significant (p < 0.05). Resolution of symptoms took a mean of 20 weeks. For those patients in whom taste change was noted, resolution of symptoms was more likely if the CTN was divided rather than preserved although the difference was not statistically significant (p < 0.5). This may reflect neuronal injury during surgery which then fails to heal normally. These results are comparable to taste outcomes in patients undertaking middle ear surgery for non-inflammatory disease such as stapedectomy. The symptoms can be extremely troublesome and may not resolve with time. Careful consideration of the CTN intra-operatively is recommended and in the event of injury, the taste outcome may be better if the nerve is divided rather than left in situ but damaged. These findings have significant implications for patients as bilateral implantation becomes more commonplace.
味觉改变是中耳手术中一个有充分文献记载但未得到充分重视的并发症，通常与鼓索神经（CTN）损伤有关。然而，此前尚未记录过人工耳蜗植入后的味觉结果。对1997年1月至2006年4月期间接受人工耳蜗植入的141例患者进行了邮寄问卷调查，询问人工耳蜗植入后味觉的变化。67%的问卷被收回。43例患者（45%）术后出现味觉改变。18例患者（19%）表示在随访期结束时（平均51个月）症状仍未缓解。CTN切断导致86%的患者出现味觉改变。50%保留CTN的患者出现味觉改变，可能与神经隐匿性损伤有关。两组中描述味觉改变的患者数量差异具有统计学意义（p<0.05）。症状缓解平均需要20周。对于那些出现味觉改变的患者，如果切断CTN而非保留CTN，症状更有可能缓解，尽管差异无统计学意义（p<0.5）。这可能反映了手术过程中的神经元损伤，随后无法正常愈合。这些结果与接受中耳手术治疗非炎性疾病（如镫骨切除术）的患者的味觉结果相当。这些症状可能极其困扰患者，且不会随时间缓解。建议术中仔细考虑CTN，如果发生损伤，切断神经而非原位保留但已受损时，味觉结果可能更好。随着双侧植入变得越来越普遍，这些发现对患者具有重要意义。
