Warren Frank M, Kaylie David M, Aulino Joseph M, Jackson C Gary, Weissman Jane L
The Otology Group at Vanderbilt, Department of Otolaryngology, Vanderbilt University Medical Center, Nashville, Tennessee 37203, USA.
Otol Neurotol. 2006 Apr;27(3):393-7. doi: 10.1097/00129492-200604000-00016.
To determine whether the appearance of the inner ear on T2-weighted follow-up magnetic resonance imaging correlates with hearing status after hearing-preservation surgery for vestibular schwannoma.
Retrospective chart review.
Tertiary referral medical center.
The study includes patients undergoing hearing-preservation surgery for vestibular schwannoma from 1998 to 2003.
Diagnostic evaluation with magnetic resonance imaging and audiometric evaluation.
Hearing results as reported in charts was correlated with appearance of membranous labyrinth on T2-weighted magnetic resonance images obtained at least 1 year after surgery.
Twenty-nine patients were identified, 16 of whom satisfied the inclusion criteria. All 16 of the patients underwent middle fossa removal of vestibular schwannoma. Serviceable hearing according to American Academy of Otolaryngology-Head and Neck Surgery criteria was preserved in eight patients (50%). Of the eight patients without serviceable hearing, six had the cochlear nerve sacrificed at the time of surgery. All patients with serviceable hearing had normal appearing cochleovestibular signal on T2-weighted images, whereas six of eight patients (75%) with no hearing or poor hearing had abnormal low signal in the inner ear, suggesting inner ear ossification. The positive predictive value of a normal labyrinth for preserved hearing was 90%, whereas the negative predictive value of an abnormal labyrinth for no hearing was 100%. All but one patient who had the cochlear nerve sacrificed showed abnormal morphology of the labyrinth on T2-weighted magnetic resonance imaging.
We describe the T2-weighted magnetic resonance findings after hearing-preservation surgery for acoustic tumor removal. Loss of inner ear signal on T2-weighted images correlates with loss of hearing postoperatively, whereas preserved inner ear signal correlates with hearing preservation after middle fossa surgery for vestibular schwannoma removal.
确定在听神经瘤保留听力手术后，T2加权序列随访磁共振成像上内耳的表现与听力状态是否相关。
回顾性病历审查。
三级转诊医疗中心。
本研究纳入了1998年至2003年间接受听神经瘤保留听力手术的患者。
磁共振成像诊断评估和听力测定评估。
病历中报告的听力结果与术后至少1年获得的T2加权磁共振图像上膜迷路的表现相关。
共确定29例患者，其中16例符合纳入标准。所有16例患者均接受了中颅窝听神经瘤切除术。根据美国耳鼻咽喉头颈外科学会标准，8例患者（50%）保留了有效听力。在8例无有效听力的患者中，6例在手术时牺牲了蜗神经。所有保留有效听力的患者在T2加权图像上蜗神经前庭信号均正常，而8例无听力或听力差的患者中有6例（75%）内耳出现异常低信号，提示内耳骨化。正常迷路对保留听力的阳性预测值为90%，而异常迷路对无听力的阴性预测值为100%。除1例牺牲蜗神经的患者外，所有患者在T2加权磁共振成像上均显示迷路形态异常。
我们描述了切除听神经瘤保留听力手术后的T2加权磁共振成像表现。T2加权图像上内耳信号消失与术后听力丧失相关，而保留内耳信号与中颅窝切除听神经瘤术后听力保留相关。
