Abstract：
OBJECTIVE: Incomplete partition type II (IP-II) is characterized by specific histological features and radiological appearance. It may occur in isolation or in association with an enlarged vestibular aqueduct (EVA). Among those with IP-II and EVA, a subset has a diagnosis of Pendred syndrome. This study aimed to explore the prevalence of isolated IP-II, IP-II with EVA, and cases with a genetic or syndromic basis in our cohort.
METHODS: From a large, multicentre database of dysplastic cochleae (446 patients, 892 temporal bones), those with imaging features of IP-II were examined in detail, including whether there was a genetic or syndromic association.
RESULTS: A total of 78 patients with IP-II were identified. Among these, 55 patients had bilateral IP-II and EVA (only 12 with typical Mondini triad), 8 with bilateral IP-II and normal VA, 2 with bilateral IP-II and unilateral EVA, and 13 with unilateral IP-II (9 with unilateral EVA). Among the group with bilateral IP-II and bilateral EVA in whom genetic analysis was available, 14 out of 29 (48%) had SLC26A4 mutations and a diagnosis of Pendred syndrome, 1 had a FOXI1 mutation, and a few other genetic abnormalities; none had KCNJ10 pathogenic variants.
CONCLUSIONS: Bilateral IP-II-bilateral EVA may be seen in the context of Pendred syndrome (SLC26A4 or FOXI1 mutations) but, in the majority of our cohort, no genetic abnormalities were found, suggesting the possibility of unknown genetic associations. IP-II in isolation (without EVA) is favored to be genetic when bilateral, although the cause is often unknown.
METHODS: From a large, multicentre database of dysplastic cochleae (446 patients, 892 temporal bones), those with imaging features of IP-II were examined in detail, including whether there was a genetic or syndromic association.
RESULTS: A total of 78 patients with IP-II were identified. Among these, 55 patients had bilateral IP-II and EVA (only 12 with typical Mondini triad), 8 with bilateral IP-II and normal VA, 2 with bilateral IP-II and unilateral EVA, and 13 with unilateral IP-II (9 with unilateral EVA). Among the group with bilateral IP-II and bilateral EVA in whom genetic analysis was available, 14 out of 29 (48%) had SLC26A4 mutations and a diagnosis of Pendred syndrome, 1 had a FOXI1 mutation, and a few other genetic abnormalities; none had KCNJ10 pathogenic variants.
CONCLUSIONS: Bilateral IP-II-bilateral EVA may be seen in the context of Pendred syndrome (SLC26A4 or FOXI1 mutations) but, in the majority of our cohort, no genetic abnormalities were found, suggesting the possibility of unknown genetic associations. IP-II in isolation (without EVA) is favored to be genetic when bilateral, although the cause is often unknown.
摘要：
目的：II型不完全分区（IP-II）的特征是特定的组织学特征和放射学外观。它可能单独发生或与扩大的前庭水管（EVA）相关。在IP-II和EVA中，一个子集被诊断为Pendred综合征。本研究旨在探讨分离IP-II的患病率，IP-II与EVA，以及我们队列中具有遗传或综合征基础的病例。
方法：从一个大的，多中心耳蜗发育不良数据库(446名患者，892颞骨），对具有IP-II成像特征的患者进行了详细检查，包括是否存在遗传或综合征关联。
结果：共确定了78例IP-II患者。其中,55例患者有双侧IP-II和EVA（只有12例具有典型的Mondini三联征），8双侧IP-II和正常VA，2与双边IP-II和单边EVA，13与单边IP-II（9与单边EVA）。在可进行遗传分析的双侧IP-II和双侧EVA的组中，29人中有14人（48%）有SLC26A4突变，诊断为Pendred综合征，1有FOXI1突变，和其他一些遗传异常；没有KCNJ10致病变异。
结论：双侧IP-II-双侧EVA可以在Pendred综合征（SLC26A4或FOXI1突变）的背景下看到，但是，在我们的大多数队列中，没有发现基因异常，暗示未知遗传关联的可能性。孤立的IP-II(没有EVA)在双边时更倾向于遗传，虽然原因往往是未知的。
方法：从一个大的，多中心耳蜗发育不良数据库(446名患者，892颞骨），对具有IP-II成像特征的患者进行了详细检查，包括是否存在遗传或综合征关联。
结果：共确定了78例IP-II患者。其中,55例患者有双侧IP-II和EVA（只有12例具有典型的Mondini三联征），8双侧IP-II和正常VA，2与双边IP-II和单边EVA，13与单边IP-II（9与单边EVA）。在可进行遗传分析的双侧IP-II和双侧EVA的组中，29人中有14人（48%）有SLC26A4突变，诊断为Pendred综合征，1有FOXI1突变，和其他一些遗传异常；没有KCNJ10致病变异。
结论：双侧IP-II-双侧EVA可以在Pendred综合征（SLC26A4或FOXI1突变）的背景下看到，但是，在我们的大多数队列中，没有发现基因异常，暗示未知遗传关联的可能性。孤立的IP-II(没有EVA)在双边时更倾向于遗传，虽然原因往往是未知的。
