Abstract：
OBJECTIVE: The aim of this study was to investigate whether the relative narrowing of the dural venous sinuses by arachnoid granulations (AGs) is more pronounced in patients with idiopathic intracranial hypertension (IIH) compared to healthy controls.
BACKGROUND: IIH is characterized by increased intracranial pressure, which is associated with symptoms such as headache and visual disturbances. The role of cerebral venous drainage obstruction in IIH is the subject of ongoing research.
METHODS: In this retrospective case-control study, 3D contrast-enhanced magnetic resonance images of a cohort of 43 patients with IIH were evaluated for (1) the number of AGs per venous sinus and (2) the diameters of the dural venous sinuses at the site of an AG and at standardized measurement points. In addition, the minimum width of the transverse/sigmoid sinus was measured. All data were compared to the same data from a cohort of 43 control participants.
RESULTS: Patients with IIH showed less relative sinus narrowing by AG compared to controls (median: 7%, interquartile range [IQR] 10% vs. 11%, IQR 9% in controls; p = 0.009). In patients with IIH, sinus diameter was larger at the site of an AG (70 ± 25 mm2) compared to its diameter at the standardized measurement point (48 ± 23 mm2; p = 0.010). In the superior sagittal sinus (SSS), patients with IIH had smaller AGs (median: 3 mm2, IQR 2 mm2 vs. 5 mm2, IQR 3 mm2 in controls; p = 0.023) while the respective sinus segment was larger (median: 69 mm2; IQR 21 mm2 vs. 52 mm2, IQR 26 mm2 in controls; p = 0.002). The right transverse sinus was narrower in patients with IIH (41 ± 21 mm vs. 57 ± 20 mm in controls; p < 0.001).
CONCLUSIONS: In contrast to our hypothesis, patients with IIH showed less pronounced relative sinus narrowing by AG compared to controls, especially within the SSS, where AGs were smaller and the corresponding sinus segment wider. Smaller AGs could result in lower cerebrospinal fluid resorption, favoring the development of IIH. Conversely, the smaller AGs could also be a consequence of IIH due to backpressure in the SSS because of the narrower transverse/sigmoid sinus, which widens the SSS and compresses the AG.
BACKGROUND: IIH is characterized by increased intracranial pressure, which is associated with symptoms such as headache and visual disturbances. The role of cerebral venous drainage obstruction in IIH is the subject of ongoing research.
METHODS: In this retrospective case-control study, 3D contrast-enhanced magnetic resonance images of a cohort of 43 patients with IIH were evaluated for (1) the number of AGs per venous sinus and (2) the diameters of the dural venous sinuses at the site of an AG and at standardized measurement points. In addition, the minimum width of the transverse/sigmoid sinus was measured. All data were compared to the same data from a cohort of 43 control participants.
RESULTS: Patients with IIH showed less relative sinus narrowing by AG compared to controls (median: 7%, interquartile range [IQR] 10% vs. 11%, IQR 9% in controls; p = 0.009). In patients with IIH, sinus diameter was larger at the site of an AG (70 ± 25 mm2) compared to its diameter at the standardized measurement point (48 ± 23 mm2; p = 0.010). In the superior sagittal sinus (SSS), patients with IIH had smaller AGs (median: 3 mm2, IQR 2 mm2 vs. 5 mm2, IQR 3 mm2 in controls; p = 0.023) while the respective sinus segment was larger (median: 69 mm2; IQR 21 mm2 vs. 52 mm2, IQR 26 mm2 in controls; p = 0.002). The right transverse sinus was narrower in patients with IIH (41 ± 21 mm vs. 57 ± 20 mm in controls; p < 0.001).
CONCLUSIONS: In contrast to our hypothesis, patients with IIH showed less pronounced relative sinus narrowing by AG compared to controls, especially within the SSS, where AGs were smaller and the corresponding sinus segment wider. Smaller AGs could result in lower cerebrospinal fluid resorption, favoring the development of IIH. Conversely, the smaller AGs could also be a consequence of IIH due to backpressure in the SSS because of the narrower transverse/sigmoid sinus, which widens the SSS and compresses the AG.
摘要：
目的：本研究的目的是研究特发性颅内高压（IIH）患者与健康对照组相比，蛛网膜颗粒（AG）引起的硬脑膜静脉窦相对狭窄是否更明显。
背景：IIH的特征是颅内压升高，这与头痛和视力障碍等症状有关。脑静脉引流阻塞在IIH中的作用是正在进行的研究的主题。
方法：在这项回顾性病例对照研究中，对43例IIH患者的3D对比增强磁共振图像进行了评估，评估了（1）每个静脉窦的AG数量和（2）AG部位和标准化测量点的硬脑膜静脉窦直径。此外,测量横窦/乙状窦的最小宽度。将所有数据与来自43名对照参与者的队列的相同数据进行比较。
结果：IIH患者与对照组相比，AG表现出较少的相对窦狭窄（中位数：7％，四分位数间距[IQR]10%vs.11%,对照中IQR为9%；p=0.009）。在IIH患者中，与标准测量点的直径（48±23mm2；p=0.010）相比，AG部位的窦直径（70±25mm2）更大。在上矢状窦（SSS），IIH患者的AG较小（中位数：3mm2，IQR2mm2与5mm2，对照中IQR3mm2；p=0.023），而相应的窦段较大（中位数：69mm2；IQR21mm2vs.52mm2，对照IQR26mm2；p=0.002）。IIH患者的右横窦较窄（41±21mmvs.对照组为57±20mm；p<0.001）。
结论：与我们的假设相反，与对照组相比，IIH患者通过AG表现出不明显的相对窦狭窄，尤其是在SSS中，其中AG较小，相应的窦段较宽。较小的AG可能导致较低的脑脊液吸收，有利于IIH的发展。相反，较小的AG也可能是IIH的结果，由于SSS中的背压，因为横向/乙状窦较窄，这扩大了SSS并压缩了AG。
背景：IIH的特征是颅内压升高，这与头痛和视力障碍等症状有关。脑静脉引流阻塞在IIH中的作用是正在进行的研究的主题。
方法：在这项回顾性病例对照研究中，对43例IIH患者的3D对比增强磁共振图像进行了评估，评估了（1）每个静脉窦的AG数量和（2）AG部位和标准化测量点的硬脑膜静脉窦直径。此外,测量横窦/乙状窦的最小宽度。将所有数据与来自43名对照参与者的队列的相同数据进行比较。
结果：IIH患者与对照组相比，AG表现出较少的相对窦狭窄（中位数：7％，四分位数间距[IQR]10%vs.11%,对照中IQR为9%；p=0.009）。在IIH患者中，与标准测量点的直径（48±23mm2；p=0.010）相比，AG部位的窦直径（70±25mm2）更大。在上矢状窦（SSS），IIH患者的AG较小（中位数：3mm2，IQR2mm2与5mm2，对照中IQR3mm2；p=0.023），而相应的窦段较大（中位数：69mm2；IQR21mm2vs.52mm2，对照IQR26mm2；p=0.002）。IIH患者的右横窦较窄（41±21mmvs.对照组为57±20mm；p<0.001）。
结论：与我们的假设相反，与对照组相比，IIH患者通过AG表现出不明显的相对窦狭窄，尤其是在SSS中，其中AG较小，相应的窦段较宽。较小的AG可能导致较低的脑脊液吸收，有利于IIH的发展。相反，较小的AG也可能是IIH的结果，由于SSS中的背压，因为横向/乙状窦较窄，这扩大了SSS并压缩了AG。
