面神经管脑脊液漏的影像学表现

The imaging presentations of the fallopian canal cerebrospinal fluid leaking

目的总结面神经管脑脊液漏(fallopian canal cerebrospinal fluid leaking,FCCFL)的影像学表现特征。方法回顾性分析2016年8月至2023年11月山东省耳鼻喉医院4例经手术证实为FCCFL患者的高分辨率CT(HRCT)和MRI影像资料,其中男2例、女2例,年龄6~69岁。结果4例FCCFL均为单侧,左、右侧各2例。临床上表现为鼻腔流清亮液体、耳闷、听力下降等症状。患耳在HRCT上均表现为近端面神经管管腔明显扩张,迷路段及膝状神经窝均受累,1例同时累及鼓室段。患侧膝状神经窝明显扩大,均向上鼓室内突出,其中1例同时累及耳蜗。在MRI上扩大的面神经管内呈T 1WI低信号,T 2WI和/或水成像序列上呈脑脊液(cerebrospinal fluid,CSF)样高信号,经扩大迷路段与内听道内CSF信号相连续;均无扩散受限,增强扫描无强化。患侧鼓室内均可见CSF样信号积液影,1例沿着岩浅大神经走行区、右侧翼腭窝及咽旁间隙可见CSF样信号。3例患侧邻近颅内脑膜增厚。结论FCCFL影像学表现具有特征性:HRCT上表现为患侧面神经管近端扩张,特别是膝状神经窝扩大;MRI上呈CSF样信号,并经迷路段与内听道内CSF相连续,弥散加权无扩散受限,增强扫描无强化,患侧鼓室内常有CSF样信号。

Objective To summarize the imaging presentations of the fallopian canal cerebrospinal fluid leaking(FCCFL).Methods The high resolution CT(HRCT)and MRI materials of 4 patients(4 ears)with FCCFL confirmed by surgery between August 2016 to November 2023 were retrospectively analyzed.Among these,there were 2 males and 2 females,their ages ranged from 6 to 69 years.Results All of the FCCFL were unilateral,including 2 on the left and 2 on the right.Clinically,the patients with FCCFL suffered from clear nasal fluid flow,ear tightness,and hearing loss.On CT,all of the affected ears were depicted markedly dilatation of the proximal portion of fallopian canal(FC),the labyrinthine segment and geniculate fossa were involved in 4 cases,and involvement of tympanic segment in 1 case at the same time.The geniculate fossa in the affected side were significantly enlarged,protruding upwards into the tympanic cavity,with one case simultaneously involving the cochlea.On MRI,the hyposignal on T 1WI and hypersignal on T 2WI or water sequence like cerebrospinal fluid(CSF)were shown in the enlargement FC,without diffusion restriction,and non-enhancing with administration Gadolinium contrast.CSF-like signal effusion was shown in all of the affected tympanum,of which,the CSF-like signal effusion was demonstrated in the area along the superficial petrosal nerve,the right pterygopalatine fossa and the parapharyngeal space.The adjacent intracranial meninges were presented thickening in 3 cases.Conclusion The imaging appearances of FCCFL present some characteristics:on HRCT,the proximal portions of the affected FC depicts markedly enlargement,especially the geniculate fossa.While they present CSF-like signal,no diffusion restriction,and no enhancement administration,Gadolinium contrast on MRI,accompanying the CSF-like signal effusion in the affected tympanum.