The influence of the subarcuate artery in the superior semicircular canal dehiscence and its frequency on stillbirths: illustrative cases and systematic review

Abstract

Literature describes that on the 25th gestational week the labyrinth is fully formed and with adult size. However, recent studies have shown that the cranial and labyrinth development continues until 3 years of age.

Objectives: To demonstrate through tomographic study the frequency of semicircular canal dehiscence on nine specimens of stillbirths between 32 and 40 weeks and, through literature review, present another possible etiology for its cause.

Methods: Tomographic study of the temporal bone of 9 specimens of stillbirths between 32 and 40 weeks.

Results: A frequency of 88.89% of alterations were found in our study, with 44% presenting bilateral alterations and 44% unilateral alteration; 11.11% had no dehiscence.

Conclusion: The tomographic study showed superior semicircular canal dehiscence (SSCD) in 88% of the specimens studied, protrusion of the superior semicircular canal (SSC) in all fetuses, and an enlarged SSC that may be caused by the expansion process provoked by the subarcuate artery entering the subarcuate canaliculus, leading to SSCD.

Chinese abstract

根据文献, 在第25孕周, 内耳迷路已经完全形成并且具有成人大小。然而, 最近的研究表明, 颅和迷路的发展一直持续到3岁。

目的：通过层析成像研究来展示在32至40周的死胎中半规管开裂的频率, 并且通过文献回顾, 为其原因提供了另一种可能的病因学研究。

方法：对9例32〜40周死胎的颞骨进行层析成像研究。

结果：我们的研究发现变化频率为88.89%, 其中44%呈双侧改变, 44%单侧改变;, 11.11%没有裂开。

结论：层析成像研究显示, 88%的标本研究显示上半规管开裂（SSCD）, 所有胎儿均出现上半规管（SSC）突起, SSC增大可能是由于亚弓形动脉进入亚弓形小管引起的扩张过程, 最终导致SSCD。

Keywords:

• Semicircular canal
• superior semicircular canal dehiscence
• subarcuate artery
• vertigo
• tinnitus

Acknowledgements

The authors thank the Department of Radiology of University of São Paulo; Vanderbilt University.

Disclosure statement

There are no disclosures for this study.

Funding

Self-funding.