Medical Faculty, Department of Otorhinolaryngology, Head and Neck Surgery, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.
Otol Neurotol. 2020 Oct;41(9):e1098-e1104. doi: 10.1097/MAO.0000000000002752.
To investigate whether ultrasound is a reliable diagnostic tool to identify magnet dislocation in patients with cochlear implant.
Retrospective analysis.
A tertiary referral medical center.
Patients with cochlear implant who presented with the suspicion of magnet dislocation between January 1, 2009 and July 31, 2019.
Preinterventional ultrasound with subsequent surgical magnet repositioning.
Accuracy of ultrasound in detecting magnet dislocation; intraoperative extent of magnet dislocation.
Out of the 28 included patients (n = 28 magnets, 36% ♀; 51.6 years [±19.0 yr]) the diagnosis by the preoperative ultrasound was confirmed intraoperatively in 25 patients (89%). In two cases (7%), tissue swelling impeded the determination of the magnet by the preoperative ultrasound. In one case, ultrasound misdiagnosed the magnet as not dislocated. During revision surgery, all 28 magnets were repositioned successfully revealing a predominant partial dislocation (86%) compared with complete magnet dislocation (14%).
In CI-patients undergoing 1.5 Tesla MRI, partial magnet dislocation occurs much more frequently than complete magnet dislocation. The clinical suspicion of a dislocated cochlear implant magnet can be accurately confirmed by preoperative ultrasound. Thus, preoperative diagnostic ultrasound can be advocated as the diagnostic tool of first choice.
探讨超声检查是否能可靠地诊断人工耳蜗植入患者磁铁脱位。
回顾性分析。
三级转诊医疗中心。
2009 年 1 月 1 日至 2019 年 7 月 31 日期间，疑似人工耳蜗植入磁铁脱位的患者。
术前超声检查，随后进行磁铁复位手术。
超声诊断磁铁脱位的准确性；术中磁铁脱位的程度。
28 例患者（28 个磁铁，36%为女性；51.6 岁[±19.0 岁]）中，25 例（89%）患者的术前超声诊断在术中得到了证实。在 2 例（7%）中，组织肿胀妨碍了术前超声对磁铁的判断。在 1 例中，超声误诊磁铁未脱位。在翻修手术中，所有 28 个磁铁均成功复位，显示出以部分脱位（86%）为主，完全磁铁脱位（14%）少见。
在接受 1.5T MRI 检查的人工耳蜗植入患者中，部分磁铁脱位比完全磁铁脱位更为常见。术前超声检查可准确诊断人工耳蜗植入磁铁脱位，因此术前诊断性超声检查可作为首选诊断工具。
