Edelmuth Diogo G L, Amrhein Timothy J, Kranz Peter G
From the Department of Radiology and Oncology (D.G.L.E.), Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
Departamento de Radiologia e Centro de Medicina Intervencionista (D.G.L.E.), Hospital Israelita Albert Einstein, São Paulo, Brazil.
AJNR Am J Neuroradiol. 2025 Apr 2;46(4):832-839. doi: 10.3174/ajnr.A8516.
The conspicuity of CSF-venous fistulas (CVFs) on specialized myelographic imaging protocols varies, and the factors that determine their visibility have not yet been extensively studied. The purpose of this study was to determine the relative effect of 2 variables on CVF visibility: timing of imaging and intrathecal contrast attenuation.
A retrospective cohort of 24 patients with spontaneous intracranial hypotension due to a CVF who underwent a total of 34 CT myelographies was studied. All CTM acquisitions that included the level of the known definite CVF were evaluated for 1) time passed after injection of contrast, 2) attenuation of the adjacent subarachnoid space, 3) subjective visibility of the CVF on that series, 4) attenuation of the corresponding draining vein, and 5) contrast dose used.
A total of 131 acquisitions included the level of the known CVFs. Attenuation values of the thecal sac were significantly higher in acquisitions where the CVFs were definitely visible (average 2283 HU) than in acquisitions where the CVFs were equivocal or not visible (764 HU and 583 HU, respectively). No significant difference was shown in the timing of the acquisitions between the 3 groups (12.8 minutes, 20.4 minutes, and 17.5 minutes, respectively). Multivariate linear regression showed thecal sac attenuation to be the only independent predictor of the attenuation of the CVF draining vein. Time passed after contrast injection was not independently correlated.
Intrathecal contrast attenuation has a strong positive relationship with the visibility of CVF. Timing of the acquisition was not an independent predictor of CVF visibility under our acquisition protocol.
脑脊液 - 静脉瘘（CVF）在专门的脊髓造影成像方案中的显见度各不相同，而决定其可见性的因素尚未得到广泛研究。本研究的目的是确定两个变量对CVF可见性的相对影响：成像时间和鞘内造影剂衰减。
对24例因CVF导致自发性颅内低压的患者进行回顾性队列研究，这些患者共接受了34次CT脊髓造影。对所有包括已知明确CVF水平的CTM采集图像进行评估，评估内容包括：1）注射造影剂后经过的时间；2）相邻蛛网膜下腔的衰减；3）该系列图像上CVF的主观可见性；4）相应引流静脉的衰减；5）使用的造影剂剂量。
共有131次采集包括已知CVF的水平。CVF明确可见的采集中，硬膜囊的衰减值（平均2283 HU）显著高于CVF不明确或不可见的采集（分别为764 HU和583 HU）。三组采集时间之间无显著差异（分别为12.8分钟、20.4分钟和17.5分钟）。多变量线性回归显示，硬膜囊衰减是CVF引流静脉衰减的唯一独立预测因素。造影剂注射后经过的时间无独立相关性。
鞘内造影剂衰减与CVF的可见性呈强正相关。在我们的采集方案下，采集时间不是CVF可见性的独立预测因素。
