Department of Radiology, University of Utah Health Sciences Center, 30 North 1900 East, #1A71, Salt Lake City, UT 84132-2140, USA.
AJR Am J Roentgenol. 2013 Aug;201(2):406-11. doi: 10.2214/AJR.12.9442.
In the setting of posterior fossa dural venous sinus thrombosis, mastoid findings can potentially be mistaken as the cause rather than a secondary effect. Obstruction of the mastoid venous drainage can lead to transudation of fluid into the mastoid air cells. We hypothesize that a continuum of the mastoid manifestations secondary to dural venous sinus thrombosis can be seen on MRI and that the difference in venous drainage between the mastoid and middle ears can assist with this important imaging differential.
A retrospective review of acute dural venous sinus thrombosis cases and their follow-up imaging were graded as follows: no involvement; grade 1 mucosal congestion; grade 2, film of fluid; or grade 3, complete opacification. Presence of middle ear fluid was also documented.
Of 22 posterior fossa dural venous sinus thrombosis cases without clinical infectious mastoiditis, 19 had mastoid findings: eight with grade 1, eight with grade 2, and three with grade 3. Middle ear fluid was seen in only one case. There was a statistically significant association between posterior fossa dural venous sinus thrombosis and mastoid findings (chisquare test (n = 22), p < 0.04). Fifteen of 18 cases with follow-up MRI examinations showed lessening of the mastoid findings with resolving dural venous sinus thrombosis.
Acute posterior fossa dural venous sinus thrombosis may present with a spectrum of mastoid findings that should not be misdiagnosed as the cause of the thrombosis. This study illustrates that in the absence of clinical findings of mastoiditis, mastoid fluid with a clear middle ear argues that the mastoid changes are the effect of the dural venous sinus thrombosis rather than the cause.
在颅后窝硬脑膜静脉窦血栓形成的情况下，乳突的表现可能会被误认为是病因，而不是继发效应。乳突静脉引流受阻可导致液体渗出到乳突气房。我们假设，在 MRI 上可以看到继发于硬脑膜静脉窦血栓形成的乳突表现的连续体，而乳突和中耳之间的静脉引流差异可以帮助进行这种重要的影像学鉴别。
回顾性分析急性硬脑膜静脉窦血栓形成病例及其随访影像学表现，分为以下几类：无受累；1 级黏膜充血；2 级，液膜；或 3 级，完全闭塞。还记录了中耳积液的存在。
在 22 例无临床感染性乳突炎的颅后窝硬脑膜静脉窦血栓形成病例中，有 19 例存在乳突表现：8 例为 1 级，8 例为 2 级，3 例为 3 级。仅在 1 例中观察到中耳积液。硬脑膜静脉窦血栓形成与乳突表现之间存在显著的统计学关联（卡方检验（n = 22），p < 0.04）。18 例有随访 MRI 检查的病例中，15 例随着硬脑膜静脉窦血栓形成的缓解，乳突表现减轻。
急性颅后窝硬脑膜静脉窦血栓形成可能表现为一系列乳突表现，不应误诊为血栓形成的原因。本研究表明，在没有乳突炎临床发现的情况下，伴有清晰中耳的乳突积液表明乳突变化是硬脑膜静脉窦血栓形成的结果，而不是原因。
