Johns Hopkins University School of Medicine, 733 N. Broadway Street, Baltimore, MD, 21205, USA.
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institution, 600 N. Wolfe St., Baltimore, MD, 21287, USA.
Neuroradiology. 2020 May;62(5):587-592. doi: 10.1007/s00234-020-02370-7. Epub 2020 Jan 24.
Vertebral artery fenestration (VAF) is a rare congenital vascular anomaly which has been associated with intracranial aneurysm. VAF can share some similar imaging features with vertebral artery dissection (VAD), which may confound diagnosis of the latter on CT and MR angiography. The purpose of this investigation is to assess the prevalence of VAF, evaluate its association with other vascular anomalies, and identify imaging features to help in distinguishing VAF and VAD.
Using keyword search on CTA and MRA head and neck imaging reports from 2010 to 2017, cases of VAF and VAD were retrospectively identified and imaging was reviewed. Imaging features including laterality; vertebral segment; length of affected segment; presence, number, and caliber of lumen(s); and presence of other vascular abnormalities were recorded for all cases and subsequently compared using Pearson's chi-squared test to assess for significant differences between the groups. Patient age, gender, and clinical presentations were also recorded.
Of 64,888 CT and MR angiographic examinations performed, VAF was identified in 67 (0.1%) and VAD in 54 (0.1%) patients. Compared with VADs, VAFs were shorter in length (p < 0.001), wider in luminal diameter (p < 0.001), more likely to occur at the V4 segment (p < 0.01), more likely to have two distinct lumens rather than one (p < 0.01), and less likely to present post-trauma (p < 0.01). Coexisting intracranial aneurysms were identified in 9% of patients with VAF.
VAFs, although rare, can be readily distinguished from VADs on angiographic imaging. Diagnosis of VAF should prompt review for intracranial aneurysm.
椎动脉窗（VAF）是一种罕见的先天性血管异常，与颅内动脉瘤有关。VAF 在 CT 和 MR 血管造影上可能与椎动脉夹层（VAD）具有一些相似的影像学特征，这可能会混淆后者的诊断。本研究旨在评估 VAF 的患病率，评估其与其他血管异常的关系，并确定有助于区分 VAF 和 VAD 的影像学特征。
使用 2010 年至 2017 年 CTA 和 MRA 头颈部成像报告中的关键字搜索，回顾性确定 VAF 和 VAD 的病例，并对影像学进行了审查。记录了所有病例的侧位、椎体节段、受累节段长度、存在、数量和管腔直径以及存在其他血管异常等影像学特征，随后使用 Pearson 卡方检验对两组之间的显著差异进行比较。还记录了患者年龄、性别和临床表现。
在 64888 次 CT 和 MR 血管造影检查中，发现 67 例（0.1%）存在 VAF，54 例（0.1%）存在 VAD。与 VAD 相比，VAF 的长度更短（p<0.001），管腔直径更宽（p<0.001），更可能发生在 V4 节段（p<0.01），更可能有两个不同的管腔而不是一个（p<0.01），且不太可能发生于创伤后（p<0.01）。9%的 VAF 患者并发颅内动脉瘤。
尽管 VAF 罕见，但在血管造影成像上可轻易与 VAD 区分开来。VAF 的诊断应提示颅内动脉瘤的检查。
