Supplementary Material for: Effect of Vestibular Dysfunction on the Development of Gross Motor Function in Children with Profound Hearing Loss

<b><i>Objective:</i></b> To evaluate the function of the superior and inferior vestibular nerve systems in children with profound sensorineural hearing loss, and to assess the influence of dysfunction of each vestibular nerve system on the development of gross motor function. <b><i>Study Design:</i></b> Retrospective study. <b><i>Setting:</i></b> A tertiary referral center. <b><i>Methods:</i></b> Eighty-nine children (age range: 20–97 months) with profound sensorineural hearing loss who were due to undergo cochlear implant surgery were recruited. Function of the superior vestibular nerve system was evaluated by the damped rotation test and the caloric test, whereas functions of the inferior vestibular nerve systems were evaluated by the vestibular evoked myogenic potential (VEMP) test. Gross motor development was assessed using the age of acquisition of head control and independent walking. <b><i>Results:</i></b> Among the children able to complete the vestibular function tests, abnormalities were found in 20% (16 of 84 children) in the damped rotation test, 41% (31 of 75 children) in the caloric test and 42% (26 of 62 children) in the VEMP test. Children who showed abnormal responses in the vestibular function tests showed significantly delayed acquisition of head control (p &lt; 0.05) and independent walking (p &lt; 0.05) in comparison with children with normal responses. The children who showed abnormal responses in all 3 vestibular tests showed the greatest delay in acquisition of gross motor function in comparison with the other groups. <b><i>Conclusions:</i></b> Children with profound hearing loss tend to have dysfunction in the superior as well as the inferior vestibular nerve systems. Both the superior and inferior vestibular nerve systems are important for the development of gross motor function in children.

**_研究目的：_** 评估重度感音神经性听力损失（profound sensorineural hearing loss）患儿的前庭上神经系统（superior vestibular nerve system）与前庭下神经系统（inferior vestibular nerve system）功能，并分析各前庭神经系统功能障碍对其粗大运动功能（gross motor function）发育的影响。
**_研究设计：_** 回顾性研究。
**_研究场景：_** 三级转诊中心。
**_研究方法：_** 招募89名拟接受人工耳蜗植入手术（cochlear implant surgery）的重度感音神经性听力损失患儿，年龄范围为20~97月龄。采用阻尼旋转试验（damped rotation test）与冷热试验（caloric test）评估前庭上神经系统功能，采用前庭诱发肌源性电位（vestibular evoked myogenic potential, VEMP）试验评估前庭下神经系统功能。通过头部控制获得年龄与独立行走年龄评估患儿粗大运动发育水平。
**_研究结果：_** 在完成前庭功能测试的患儿中，阻尼旋转试验异常率为20%（84名患儿中16名），冷热试验异常率为41%（75名患儿中31名），前庭诱发肌源性电位试验异常率为42%（62名患儿中26名）。与前庭功能测试结果正常的患儿相比，测试结果异常的患儿头部控制与独立行走获得时间均显著延迟（p < 0.05）。在全部3项前庭测试中均出现异常的患儿，其粗大运动功能发育延迟程度较其他组别更为显著。
**_研究结论：_** 重度听力损失患儿往往存在前庭上、下神经系统功能障碍。前庭上、下神经系统均对患儿粗大运动功能发育具有重要作用。