Objective:To evaluate the relationship between transverse sinus stenosis (TSS) and cerebral blood flow in normal adults based on four-dimensional flow (4D Flow) MRI.Methods:The study was a cross-sectional study. Totally 81 normal volunteers who underwent magnetic resonance venography (MRV) and 4D Flow MRI were prospectively enrolled at Beijing Friendship Hospital, Capital Medical University from January 2020 to December 2022. Based on MRV evaluation of transverse sinus dysplasia, the volunteers were divided into a dysplasia group (26 cases) and a non-dysplasia group (55 cases); The area of the stenosis and the normal transverse sinus at the distal end were measured. The degree of TSS and the bilateral average transverse sinus stenosis (BA-TSS) were calculated. TSS was determined using TSS levels of 1/3, 1/2, and 2/3 as thresholds, and was divided into three groups: no TSS group, unilateral TSS group, and bilateral TSS group, with 28, 39, and 14 cases, 37, 37, and 7 cases, and 43, 36, and 2 cases, respectively. Based on 4D Flow MRI, the blood flow of the internal carotid artery, vertebral artery, superior sagittal sinus, straight sinus, and transverse sinus distal and proximal ends were measured. The cerebral blood flow (bilateral internal carotid artery blood flow+bilateral vertebral artery blood flow), venous sinus return blood flow 1 (superior sagittal sinus blood flow+straight sinus blood flow), return blood flow 2 (sum of bilateral transverse sinus distal end blood flow), return blood flow 3 (sum of bilateral transverse sinus proximal end blood flow), and the ratio of return blood flow to cerebral blood flow were calculated. Independent sample t-test was used to compare the differences between the group with and without transverse sinus dysplasia; Single factor analysis of variance was used to compare the differences between the TSS free group, unilateral TSS group, and bilateral TSS group. Based on single factor linear regression, the relationships between BA-TSS and blood flow parameters were analyzed.Results:There was no statistically significant difference in various blood flow parameters between the group with and without transverse sinus dysplasia (all P>0.05). When using 1/3, 1/2, and 2/3 as thresholds, there was no statistically significant difference in various blood flow parameters between the non TSS group, unilateral TSS group, and bilateral TSS group (all P>0.05). BA-TSS was linearly positively correlated with cerebral blood flow (β=0.986, 95% CI 0.108-1.865, P=0.028), but not linearly correlated with return blood flow 1, 2, and 3 (all P>0.05). The degree of BA-TSS was linearly negatively correlated with return blood flow 1/cerebral blood flow (β=-0.001, 95% CI -0.002-0, P=0.009) and return blood flow 2/cerebral blood flow (β=-0.001, 95% CI -0.002-0, P=0.018), but not with return blood flow 3/cerebral blood flow ( P=0.076). Conclusion:The BA-TSS degree in normal adults is positively correlated with cerebral blood inflow and negatively correlated with the proportion of venous sinus outflow.

Objective:To evaluate the relationship between transverse sinus stenosis (TSS) and cerebral blood flow in normal adults based on four-dimensional flow (4D Flow) MRI.Methods:The study was a cross-sectional study. Totally 81 normal volunteers who underwent magnetic resonance venography (MRV) and 4D Flow MRI were prospectively enrolled at Beijing Friendship Hospital, Capital Medical University from January 2020 to December 2022. Based on MRV evaluation of transverse sinus dysplasia, the volunteers were divided into a dysplasia group (26 cases) and a non-dysplasia group (55 cases); The area of the stenosis and the normal transverse sinus at the distal end were measured. The degree of TSS and the bilateral average transverse sinus stenosis (BA-TSS) were calculated. TSS was determined using TSS levels of 1/3, 1/2, and 2/3 as thresholds, and was divided into three groups: no TSS group, unilateral TSS group, and bilateral TSS group, with 28, 39, and 14 cases, 37, 37, and 7 cases, and 43, 36, and 2 cases, respectively. Based on 4D Flow MRI, the blood flow of the internal carotid artery, vertebral artery, superior sagittal sinus, straight sinus, and transverse sinus distal and proximal ends were measured. The cerebral blood flow (bilateral internal carotid artery blood flow+bilateral vertebral artery blood flow), venous sinus return blood flow 1 (superior sagittal sinus blood flow+straight sinus blood flow), return blood flow 2 (sum of bilateral transverse sinus distal end blood flow), return blood flow 3 (sum of bilateral transverse sinus proximal end blood flow), and the ratio of return blood flow to cerebral blood flow were calculated. Independent sample t-test was used to compare the differences between the group with and without transverse sinus dysplasia; Single factor analysis of variance was used to compare the differences between the TSS free group, unilateral TSS group, and bilateral TSS group. Based on single factor linear regression, the relationships between BA-TSS and blood flow parameters were analyzed.Results:There was no statistically significant difference in various blood flow parameters between the group with and without transverse sinus dysplasia (all P>0.05). When using 1/3, 1/2, and 2/3 as thresholds, there was no statistically significant difference in various blood flow parameters between the non TSS group, unilateral TSS group, and bilateral TSS group (all P>0.05). BA-TSS was linearly positively correlated with cerebral blood flow (β=0.986, 95% CI 0.108-1.865, P=0.028), but not linearly correlated with return blood flow 1, 2, and 3 (all P>0.05). The degree of BA-TSS was linearly negatively correlated with return blood flow 1/cerebral blood flow (β=-0.001, 95% CI -0.002-0, P=0.009) and return blood flow 2/cerebral blood flow (β=-0.001, 95% CI -0.002-0, P=0.018), but not with return blood flow 3/cerebral blood flow ( P=0.076). Conclusion:The BA-TSS degree in normal adults is positively correlated with cerebral blood inflow and negatively correlated with the proportion of venous sinus outflow.

Objective:To investigate the hemodynamic characteristics of transverse sinus with sigmoid sinus wall dehiscence (SSWD) of pulsatile tinnitus (PT) based on 4D flow MRI.Methods:Retrospective analysis was performed on all patients admitted to Beijing Friendship Hospital, Capital Medical University from January 2019 to January 2021 for dehiscent sigmoid plate pulsatile tinnitus. A total of 26 patients (sides) who met the criteria and underwent 4D flow MRI were included. A total of 26 subjects (46 sides), matched 1∶1 according to gender and age, were included in the normal healthy control group. Nonparametric rank sum test, Student′s t test, and ANOVA were performed by SPSS 19.0 software. Binary Logistic regression was applied to the data with statistical significance. Results:There were more patients with dominant drainage on the affected side in PT group than in control group (73.1% vs. 42.3%). The incidence of transverse with a focal intraluminal filling defect and tapered stenosis was higher than that in control group (21.7% vs. 69.2%; 17.4% vs. 42.3%). Average through-plane velocity and maximum through-plane velocity in PT group were higher than those in control group [(33.75±13.88) cm/s vs. (15.84±7.21) cm/s; (93.19±33.55) cm/s vs. (40.40±14.40) cm/s]. The middle part and proximal end of Flow avg (ml/s) in PT group were larger than those in control group [4.69 (2.87; 5.62) ml/s vs. 2.76 (1.67; 4.99) ml/s; 3.41 (2.16; 5.47) ml/s vs. 2.67 (1.68; 4.41) ml/s]. In control group, the velocity of transverse sinus changed relatively gently, while in PT group, the velocity of proximal sinus increased significantly. Binary Logistic regression showed that SSWD PT was independently correlated with proximal maximum flow velocity [ OR=1.086(1.029-1.146), P=0.003]. Conclusion:4D flow MRI showed that the dominant drainage and higher velocity at the proximal end of the transverse sinus might be an important hemodynamic characteristics of dehiscent sigmoid plate pulsatile tinnitus.

Transverse sinus is an important pathway of intracranial venous reflux,which is also crucial for maintaining cerebral circulation and stabilizing intracranial pressure.Transverse sinus stenosis(TSS)is the most common variation of transverse sinus,which might lead to changes in sinus hemodynamics and pressure and closely related to idiopathic intracranial hypertension,pulsatile tinnitus and chronic headache.The progresses in imaging researches of transverse sinus stenosis were reviewed in this article.