Department of Diagnostic and Interventional Neuroradiology, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany.
Radiology. 2011 Jun;259(3):825-33. doi: 10.1148/radiol.11101466. Epub 2011 Mar 8.
To determine the frequency and to describe the morphologic characteristics and associated skull base anomalies of the petrosquamosal sinus (PSS) in cochlear implant candidates with complete aplasia of the semicircular canals (SCCs).
Ethics committee approval was obtained. Index cases were retrospectively selected from an electronic database in which all inner ear malformations observed in patients presenting to a tertiary referral center between 1995 and 2010 were collected. Computed tomography (CT) data were reviewed by neuroradiologists. Clinical consequences of the neuroradiologic findings were analyzed. The Pearson χ(2) test and the Mann-Whitney U test were used to determine significant differences between the number of PSSs observed in cases of complete aplasia of the SCCs and the number observed in cases of other types of inner ear malformations.
Inner ear malformations were analyzed in 241 patients. Thirty-one patients (13%) with bilateral SCC aplasia were identified. Among 31 patients, a uni- or bilateral PSS was observed in 25 (81%). In the ears with SCC aplasia, a PSS was observed in 40 (65%) of 62. The three cases in which these PSS occupy the largest area correlate with bilateral absence of the jugular foramen. In seven of eight ears with a PSS, the PSS inhibited surgical exposure or resulted in accidental opening of the PSS during surgery. In all other patients with inner ear malformations, a PSS was observed in 39 (9%) of 412 ears only.
The PSS presents a risk for cochlear implant surgery that can be detected by the neuroradiologist in advance. Venous CT angiography is advisable in certain cases. The previous assumption that a persistent PSS is encountered more frequently in cases of skull base deformity can be affirmed in the special situation of complete aplasia of the SCCs.
确定在半规管（SCC）完全发育不全的耳蜗植入候选者中，岩鳞窦（PSS）的出现频率，并描述其形态特征和相关颅底异常。
获得伦理委员会批准。从电子数据库中回顾性选择索引病例，该数据库收集了 1995 年至 2010 年期间在三级转诊中心就诊的所有内耳畸形患者的内耳畸形。神经放射科医生对 CT 数据进行了复查。分析了神经影像学发现的临床后果。采用 Pearson χ(2)检验和 Mann-Whitney U 检验来确定在 SCC 完全发育不全的病例中观察到的 PSS 数量与其他类型内耳畸形病例中观察到的 PSS 数量之间的差异是否有统计学意义。
共分析了 241 例内耳畸形患者。发现 31 例（13%）双侧 SCC 发育不全的患者。在 31 例患者中，25 例（81%）观察到单侧或双侧 PSS。在 SCC 发育不全的耳朵中，40 例（65%）观察到 PSS。这 3 个 PSS 占据最大面积的病例与双侧颈静脉孔缺失相关。在 8 例存在 PSS 的耳朵中，PSS 妨碍了手术暴露，或者在手术中意外打开了 PSS。在所有其他内耳畸形患者中，仅在 39 例（9%）的 412 例耳朵中观察到 PSS。
神经放射科医生可以预先发现 PSS 会给耳蜗植入手术带来风险。在某些情况下，建议进行静脉 CT 血管造影。在 SCC 完全发育不全的特殊情况下，可以证实先前假设的颅底畸形中更常遇到持续 PSS 的假设。
