Cerebral Sinus Hemodynamics in Adults Revealed by 4D Flow MRI.

BACKGROUND: The hemodynamics of the cerebral sinuses play a vital role in understanding blood flow-related diseases, yet the hemodynamics of the cerebral sinuses in normal adults remains an unresolved issue. PURPOSE: To evaluate hemodynamics in the cerebral sinus of adults using 4-dimensional flow MRI (4D Flow MRI). STUDY TYPE: Cross-sectional. POPULATION: Ninety-nine healthy volunteers (mean age, 42.88 ± 13.16 years old; females/males, 55/44). FIELD STRENGTH/SEQUENCE: 3 T/4D Flow MRI. ASSESSMENT: The blood flow velocity, average blood flow rate (Q), and vortexes at the superior sagittal sinus (SSS), straight sinus (STS), transverse sinus, sigmoid sinus, and jugular bulb of each volunteer were evaluated by two independent neuroradiologists. The relationship between the total cerebral Q and sex and age was also assessed. Twelve volunteers underwent two scans within a month. STATISTICAL TESTS: The intraclass correlation coefficient (ICC) evaluated the inter-observer agreement. Blood flow parameters among volunteers were compared by the independent-sample t-test or Mann-Whitney U test. The multiple linear regression equation was used to evaluate the relationship between total cerebral Q and age and sex. P < 0.05 indicated statistical significance. RESULTS: The test-retest and interobserver reliability of average velocity and Q were moderate to high (ICC: 0.54-0.99). Cerebral sinus velocity varied by segment and cardiac cycle. The SSS's velocity and Q increased downstream and Q near torcular herophili was 3.5 times that through the STS. The total cerebral Q decreased by 0.06 mL/s per year (ß = -0.06 ± 0.013) and was sex-independent within the group. Vortexes were found in 12.12%, 8.9%, and 59.8% of torcular herophili, transverse-sigmoid junction, and jugular bulb, respectively, and were related to higher upstream flow. DATA CONCLUSION: Cerebral sinuses could be measured visually and quantitatively in vivo by 4D Flow MRI, providing a basis for future research on pulsating tinnitus, multiple sclerosis, and other related diseases. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.

CT evaluation of unilateral pulsatile tinnitus with jugular bulb wall dehiscence.

OBJECTIVES: To investigate the imaging features of unilateral pulsatile tinnitus (PT) with jugular bulb wall dehiscence (JBWD). METHODS: Computerized tomography angiography images of unilateral PT patients were reviewed between 2019 and 2021. Thirty-one symptomatic JBWD patients without sigmoid sinus wall dehiscence (SSWD) were included. Thirty-eight patients with SSWD were used as the control group. The prevalence of JBWD was calculated. The area and height of the jugular bulb, the extent of dehiscence, the presence of jugular bulb diverticulum, posterior condylar emissary vein (PCEV), oblique occipital sinus (OOS), venous outflow laterality (VOL), the degree of transverse sinus stenosis (TSS), and the pituitary height to sella turcica ratio were compared between the two groups. RESULTS: The prevalence of JBWD was 12.1%, and JBWD was established as a causative diagnosis in 5.0% of unilateral PT patients. There were no statistical differences in the gender, symptomatic side, or VOL between the two groups. The area of the jugular bulb was larger and the height was higher (parea < 0.001, pheight = 0.005). The prevalence of jugular bulb diverticulum was higher in the JBWD group (p = 0.002). The degree of symptomatic TSS was less severe (p < 0.001), and the prevalence of bilateral TSS was lower in the JBWD group (p < 0.001). The pituitary height to sella turcica ratio was greater (p = 0.004), the prevalence of PCEV (p = 0.014) was lower, and OOS (p = 0.015) was greater in the JBWD group. CONCLUSIONS: The correlating factors of PT with JBWD and PT with SSWD are significantly different. These findings can further facilitate early and efficient PT treatment. KEY POINTS: • The incidence of jugular bulb dehiscence (JBWD) accounted for approximately 12.1% in pulsatile tinnitus (PT) patients, and JBWD was established as a causative diagnosis in 5.0% of PT patients. • PT required large blood flows and abnormal flow patterns, whether in JBWD or sigmoid sinus wall dehiscence groups. • JBWD causing PT has some unique characteristic findings on CT.

Potential of ultra-high-resolution CT in detecting osseous changes of temporomandibular joint: experiences in temporomandibular disorders.

BACKGROUND: Osseous changes of the temporomandibular joint (TMJ) are related to the progression of temporomandibular disorders (TMD), and computed tomography (CT) plays a vital role in disease evaluation. OBJECTIVE: The aims of this study were to evaluate the image quality and diagnostic value of ultra-high-resolution CT (U-HRCT) in TMD compared to cone-beam CT (CBCT). METHODS: TMD patients who underwent both CBCT and U-HRCT between November 2021 and September 2022 were retrospectively included. Image quality scores were assigned for four osseous structures (the cortical and trabecular bones of the condyle, articular eminence, and glenoid fossa) by two independent observers from Score 1 (unacceptable) to Score 5 (excellent). Diagnostic classification of TMD was categorized as follows: Class A (no evident lesion), Class B (indeterminate condition) and Class C (definitive lesion). Image quality scores and diagnostic classifications were compared between CBCT and U-HRCT. The Cohen's Kappa test, Wilcoxon signed-rank test, Chi-square test and Fisher's exact test were conducted for statistical analysis. RESULTS: Thirty TMD patients (median age, 30 years; interquartile range, 26-43 years; 25 females) with 60 TMJs were enrolled. Image quality scores were higher for U-HRCT than for CBCT by both observers (all Ps < 0.001). Definitive diagnoses (Class A and C) were achieved in more cases with U-HRCT than with CBCT (93.3% vs. 65.0%, Fisher's exact value = 7.959, P = 0.012). Among the 21 cases which were ambiguously diagnosed (Class B) by CBCT, definitive diagnosis was achieved for 17 cases (81.0%) using U-HRCT. CONCLUSIONS: U-HRCT can identify osseous changes in TMD, providing improved image quality and a more definitive diagnosis, which makes it a feasible diagnostic imaging method for TMD.

Effects of different morphologic abnormalities on hemodynamics in patients with venous pulsatile tinnitus: A four-dimensional flow magnetic resonance imaging study.

The effects of morphologic abnormalities, including sigmoid sinus wall dehiscence (SSWD), transverse sinus stenosis (TSS), and sigmoid sinus diverticulum (SSD), on hemodynamics in venous pulsatile tinnitus (PT) patients have not been established. The aim of this study was to evaluate the effects of SSWD, TSS, and SSD on the hemodynamics of transverse-sigmoid sinus in venous PT patients. This was a prospective study with 44 venous PT patients and 12 healthy controls. A 3 T/four-dimensional (4D) flow magnetic resonance imaging with fast field echo was used. Computed tomography arteriography/venography was used to assess ipsilateral SSWD, TSS, and SSD. Maximum velocity (Vmax ), average velocity (Vavg ), and average flow (Flowavg ) were measured. Blood flow patterns were independently assessed by three neuroradiologists. One-way analysis of variance or Kruskal-Wallis test was also used. On the symptomatic side, all patients had SSWD, 33 patients had TSS, and 22 patients had SSD. Compared with healthy controls, patients with TSS, without TSS, with SSD, and without SSD all showed higher Vmax (all p < 0.050), Vavg (all p < 0.050), and Flowavg (all p < 0.050). Patients with TSS showed higher Vmax (p < 0.050) and Vavg (p < 0.050) than those without TSS, and no significant difference in Flowavg was found between the two groups (p = 0.408). No significant differences in Vmax , Vavg , and Flowavg were found between patients with and without SSD (all p = 1.000). Jet-like flow in the stenosis and downstream of the stenosis was observed in all patients with TSS. Vortex in SSD was observed in 15 patients with SSD (68%). High blood velocity and flow may be characteristic markers of venous PT. SSWD may be a necessary condition for venous PT. TSS may further increase the blood velocity and form a jet-like flow. SSD may be related to vortex formation but had no significant effect on blood velocity and flow. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 3.

CT venography correlate of transverse sinus stenosis and venous transstenotic pressure gradient in unilateral pulsatile tinnitus patients with sigmoid sinus wall anomalies.

OBJECTIVES: To investigate the correlation between transverse sinus stenosis (TSS) and transstenotic pressure gradient (TPG) in unilateral pulsatile tinnitus (PT) patients with sigmoid sinus wall anomalies (SSWA). METHODS: Fifty-seven patients with unilateral venous PT were retrospectively included. All of them underwent CT venography and catheter manometry, accompanied with SSWA. The degree, length, shape (intrinsic/extrinsic/dysplasia), location (proximal/middle/distal, referring to the relative position of TSS and the Labbé vein junction) of TSS, the types of SSWA (dehiscence/diverticulum), and the degree of transverse sinus outflow laterality were assessed, and the correlations with ipsilesional TPG were analyzed. RESULTS: The mean value of ipsilesional TPG was 7.61 ± 0.52 mmHg. The degree and length of ipsilesional TSS were positively correlated with TPG (p < 0.001, p' < 0.001), respectively. TPG was significantly larger in patients with contralateral transverse sinus dysplasia than those without (p = 0.023) and significantly smaller in patients with ipsilesional sigmoid sinus diverticulum than those with isolated dehiscence (p = 0.001). No statistical difference in TPG was shown between ipsilesional TSSs of different shapes or locations (p > 0.05). No correlation was noted between the degree of ipsilesional transverse sinus outflow laterality and TPG (p = 0.051). Stepwise linear regression indicated that the degree (ß = 9.207, 95% CI = 3.558-14.856), length (ß = 0.122, 95% CI = 0.025-0.220) of ipsilesional TSS, and contralateral transverse sinus dysplasia (ß = 1.875, 95% CI = 0.220-3.530) were significantly correlated with TPG (R2 = 0.471). CONCLUSIONS: The degree, length of ipsilesional TSS, and contralateral transverse sinus dysplasia may be used to predict TPG in unilateral PT patients with SSWA. KEY POINTS: • CT venography may act as a screening tool to help low-probability unilateral pulsatile tinnitus (PT) patients with sigmoid sinus wall anomalies (SSWA) avoid invasive catheter manometry. • The degree and length of ipsilesional transverse sinus stenosis (TSS) are positively correlated with transtenotic pressure gradient (TPG) in unilateral PT patients with SSWA. • Ipsilesional TPG is larger in unilateral PT patients with contralateral transverse sinus dysplasia than those without and is smaller in unilateral PT patients with sigmoid sinus diverticulum than those with isolated dehiscence.

Hierarchical integrated processing of reward-related regions in obese males: A graph-theoretical-based study.

Abnormal activities in reward-related regions are associated with overeating or obesity. Preliminary studies have shown that changes in neural activity in obesity include not only regional reward regions abnormalities but also impairments in the communication between reward-related regions and multiple functional areas. A recent study has shown that the transitions between different neural networks are nonrandom and hierarchical, and that activation of particular brain networks is more likely to occur after other brain networks. The aims of this study were to investigate the key nodes of reward-related regions in obese males and explore the hierarchical integrated processing of key nodes. Twenty-four obese males and 24 normal-weight male controls of similar ages were recruited. The fMRI data were acquired using 3.0 T MRI. The fMRI data preprocessing was performed in DPABI and SPM 12. Degree centrality analyses were conducted using GRETNA toolkit, and Granger causality analyses were calculated using DynamicBC toolbox. Decreased degree centrality was observed in left ventral medial prefrontal cortex (vmPFC) and right parahippocampal/hippocampal gyrus in group with obesity. The group with obesity demonstrated increased effective connectivity between left vmPFC and several regions (left inferior temporal gyrus, left supplementary motor area, right insular cortex, right postcentral gyrus, right paracentral lobule and bilateral fusiform gyrus). Increased effective connectivity was observed between right parahippocampal/hippocampal gyrus and left precentral/postcentral gyrus. Decreased effective connectivity was found between right parahippocampal/hippocampal gyrus and left inferior parietal lobule. This study identified the features of hierarchical interactions between the key reward nodes and multiple function networks. These findings may provide more evidence for the existing view of hierarchical organization in reward processing.

Patterns of Gray Matter Volume Alterations in Hemodialysis Patients With and Without Restless Legs Syndrome: Evidence From a Voxel-Based Morphometry Study.

PURPOSE: The purpose of this study was to investigate the differences of gray matter volume (GMV) alteration patterns between hemodialysis with restless legs syndrome (HD-RLS) and hemodialysis without restless legs syndrome (HD-nRLS) patients using voxel-based morphometry. METHODS: Twenty-three HD-RLS patients, 27 HD-nRLS patients, and 27 age-, sex-, and education-matched healthy controls were included in this study. One-way analysis of covariance and post hoc analyses were used to assess differences in GMV, demographics, and clinical data among the 3 groups. Pearson correlation analysis was conducted between altered GMV in the HD-RLS group and clinical data. RESULTS: Compared with HD-nRLS patients, HD-RLS patients showed decreased GMV in the left primary motor cortex (false discovery rate corrected, P < 0.05). Compared with the healthy controls, both HD subgroups (ie, those with and without RLS) exhibited consistent GMV changes, including decreased GMV in the bilateral anterior cingulate and paracingulate gyrus and left middle temporal gyrus (false discovery rate corrected, P < 0.05). The GMV values in the left precentral gyrus were negatively correlated with the RLS rating scores (r = 0.2138, P = 0.0263). CONCLUSIONS: This abnormal decreased GMV in the sensorimotor cortex provides evidence for a sensory processing disorder in RLS that may be involved in the pathogenesis of RLS in HD patients.

Integration of Neural Reward Processing and Appetite-Related Signaling in Obese Females: Evidence From Resting-State fMRI.

BACKGROUND: The reward-related regions have been considered a crucial component in the regulation of eating behavior. Furthermore, appetite-related regions associated with reward can influence eating behaviors through altered functional activity related to food in brain areas associated with emotion, memory, sensory processing, motor function, and cognitive control. PURPOSE: To investigate the key nodes in obese females of reward-related regions and, based on key nodes, to evaluate the directionality of functional connectivity between key nodes and appetite-related regions. STUDY TYPE: Prospective. POPULATION: Twenty-eight obese and 28 normal-weight female controls of similar age. FIELD STRENGTH/SEQUENCE: 3.0 T MRI and echo planar imaging (EPI) sequence, 3D BRAVO sequence. ASSESSMENT: The fMRI data preprocessing was based on the Data Processing & Analysis of Brain Imaging and Statistical Parametric Mapping 12. Degree centrality calculation was based on the GRETNA toolkit and granger causality analysis were based on the DynamicBC toolbox. Statistical Tests: Independent two-sample t-tests were used to assess the differences in demographic and clinical data between two groups. Two-sample t-tests were conducted to test the difference in degree centrality and effective connectivity of key nodes between two groups. RESULTS: Compared with normal-weight controls, obese females showed an increased degree centrality in the left ventral striatum/caudate (t = 2.96808, P < 0.05) and decreased degree centrality in right orbitofrontal cortex (OFC) (t = -3.3558, P < 0.05). The obese females showed directional effective connectivity between left ventral striatum/caudate and several regions (left inferior temporal gyrus, fusiform gyrus, postcentral gyrus, and right precentral gyrus) (P < 0.05). Directional effective connectivity was also observed between the right OFC and several regions (left middle temporal gyrus, cuneus, OFC, superior temporal gyrus, middle frontal gyrus, and right inferior parietal lobule) (P < 0.05). DATA CONCLUSION: The left ventral striatum/caudate and right OFC are key nodes in reward-related regions. The key nodes with reward processing mainly enhance visual processing of information and further participate in cognitive, attention, and sensorimotor processing. LEVEL OF EVIDENCE: 1. Technical Efficacy: Stage 4. J. Magn. Reson. Imaging 2019;50:541-551.

Temporal bone contrast-enhanced high-resolution CT evaluation of pulsatile tinnitus after sigmoid sinus wall reconstruction.

BACKGROUND: Sigmoid sinus wall reconstruction (SSWR) is a proven effective treatment for pulsatile tinnitus (PT) caused by sigmoid sinus wall dehiscence (SSWD) with or without sigmoid sinus diverticulum (SSD); however, comprehensive analysis of the postoperative imaging manifestations has not yet been reported. PURPOSE: To analyze temporal bone computed tomography (CT) imaging features following SSWR in patients with PT. MATERIAL AND METHODS: Following SSWR, temporal bone contrast-enhanced high-resolution CT (HRCT) images from 33 PT cases were retrospectively analyzed. Patients were divided into two groups based on follow-up interval: a short-interval group (≤18 months, 12 cases) and a long-interval group (>18 months, 21 cases). The mending material density and morphology was analyzed. Postoperative changes of the venous sinus were evaluated. Imaging manifestations of the normal temporal bone and mastoid air cells adjacent to the operative field were observed. RESULTS: The order of CT values of mending materials was significantly lower in the short-interval group than in the long-interval group (Z = -4.716, P < 0.001); the incidence of complete newly remodeled cortical bone on the rim of the mending materials was significantly higher in the long-interval group than in the short-interval group ( P < 0.001). Eleven patients (33.3%) showed varying degrees of remnant SSWD. The mending materials and normal mastoid bone structure showed complete fusion (n = 12, 36.4%), partial fusion (n = 16, 48.5%), or complete separation (n = 5, 15.2%). CONCLUSION: Temporal bone contrast-enhanced HRCT can be used to observe imaging features of the mending materials, venous sinus, adjacent normal temporal bone and mastoid air cells following SSWR.

Morphological Neuroimaging Biomarkers for Tinnitus: Evidence Obtained by Applying Machine Learning.

According to previous studies, many neuroanatomical alterations have been detected in patients with tinnitus. However, the results of these studies have been inconsistent. The objective of this study was to explore the cortical/subcortical morphological neuroimaging biomarkers that may characterize idiopathic tinnitus using machine learning methods. Forty-six patients with idiopathic tinnitus and fifty-six healthy subjects were included in this study. For each subject, the gray matter volume of 61 brain regions was extracted as an original feature pool. From this feature pool, a hybrid feature selection algorithm combining the F-score and sequential forward floating selection (SFFS) methods was performed to select features. Then, the selected features were used to train a support vector machine (SVM) model. The area under the curve (AUC) and accuracy were used to assess the performance of the classification model. As a result, a combination of 13 cortical/subcortical brain regions was found to have the highest classification accuracy for effectively differentiating patients with tinnitus from healthy subjects. These brain regions include the bilateral hypothalamus, right insula, bilateral superior temporal gyrus, left rostral middle frontal gyrus, bilateral inferior temporal gyrus, right inferior parietal lobule, right transverse temporal gyrus, right middle temporal gyrus, right cingulate gyrus, and left superior frontal gyrus. The accuracy in the training and test datasets was 80.49% and 80.00%, respectively, and the AUC was 0.8586. To the best of our knowledge, this is the first study to elucidate brain morphological changes in patients with tinnitus by applying an SVM classifier. This study provides validated cortical/subcortical morphological neuroimaging biomarkers to differentiate patients with tinnitus from healthy subjects and contributes to the understanding of neuroanatomical alterations in patients with tinnitus.

Growth pattern of temporal bone pneumatization: a computed tomography study with consecutive age groups.

PURPOSE: To investigate the growth pattern of temporal bone pneumatization (TBP) in consecutive age groups from birth to 18 years old using 3D air-density reconstruction of high-resolution CT (HRCT). METHODS: A total of 570 patients under 18 years old who performed temporal bone HRCT and with no structural abnormalities on both sides were included. Nineteen groups were created to represent consecutive ages, with 15 males and 15 females in each group. Volume rendering of air density was performed using a segmentation threshold of - 200 HU to obtain TBP volume of each side. The differences in TBP between the sides, sexes, and ages were statistically analyzed. RESULTS: The mean volume of TBP was measured as 1.17 ± 0.44 ml in patients less than 1 year old and 6.81 ± 1.93 ml as adult size. High consistencies of TBP volume between different sides or sexes were found in most of age groups. Significant differences were shown between sides only in 9- and 11-year-old female groups (p9 = 0.031, p11 = 0.016) while between sexes only in 6- and 16-year-old groups (p6 = 0.001, p16 = 0.043), although the volume was larger in all the male groups older than 6 years. The curve drawn by the mean volume in consecutive age groups showed that TBP continued to grow linearly in both males and females until they reached 14 years old. The corresponding linear regression equations were as follows: ym = 1.553 + 0.370x, (x ≤ 14 years, R2 = 0.596); yf = 1.561 + 0.304x, (x ≤ 14 years, R2 = 0.565). CONCLUSION: The TBP volume shows a linear growth pattern from birth until reaching adult size after 14 years old.

Utility of machine learning for identifying stapes fixation on ultra-high-resolution CT.

PURPOSE: Imaging diagnosis of stapes fixation (SF) is challenging owing to a lack of definite evidence. We developed a comprehensive machine learning (ML) model to identify SF on ultra-high-resolution CT. MATERIALS AND METHODS: We retrospectively enrolled 109 participants (143 ears) and divided them into the training set (115 ears) and test set (28 ears). Stapes mobility (SF or non-SF) was determined by surgical inspection. In the ML analysis, rectangular regions of interest were placed on consecutive axial slices in the training set. Radiomic features were extracted and fed into the training session. The test set was analyzed using 7 ML models (support vector machine, k nearest neighbor, decision tree, random forest, extra trees, eXtreme Gradient Boosting, and Light Gradient Boosting Machine) and by 2 dedicated neuroradiologists. Diagnostic performance (sensitivity, specificity and accuracy, with surgical findings as the reference) was compared between the radiologists and the optimal ML model by using the McNemar test. RESULTS: The mean age of the participants was 42.3 ± 17.5 years. The Light Gradient Boosting Machine (LightGBM) model showed the highest sensitivity (0.83), specificity (0.81), accuracy (0.82) and area under the curve (0.88) for detecting SF among the 7 ML models. The neuroradiologists achieved good sensitivities (0.75 and 0.67), moderate-to-good specificities (0.63 and 0.56) and good accuracies (0.68 and 0.61). This model showed no statistical differences with the neuroradiologists (P values 0.289-1.000). CONCLUSIONS: Compared to the neuroradiologists, the LightGBM model achieved competitive diagnostic performance in identifying SF, and has the potential to be a supportive tool in clinical practice.

Association Between Vestibular Aqueduct Morphology and Meniere's Disease.

OBJECTIVE: To investigate the relationship between vestibular aqueduct (VA) morphology and Meniere's disease (MD) using ultrahigh-resolution computed tomography (U-HRCT). METHODS: Retrospective data were collected from 34 patients (40 ears) diagnosed with MD in our hospital who underwent temporal bone U-HRCT with isotropic 0.05-mm resolution, magnetic resonance with gadolinium-enhanced, and pure-tone audiometry; 34 age- and sex-matched controls (68 ears) who underwent U-HRCT were also included. VA patency was qualitatively classified as locally not shown (grade 1), locally faintly shown (grade 2), or clearly shown throughout (grade 3). The width of the outer orifice and VA length and angle were quantitatively measured. Differences in VA morphology between the MD and control groups were analyzed. The correlations between VA morphology and the degrees of hearing loss and endolymphatic hydrops (EH) were also analyzed. RESULTS: VA was classified as grades 1-3 in 11, 17, and 12 ears in the MD group and 5, 26, and 37 ears in the control group, respectively. The patency differed significantly between the groups (p < 0.01). The width of the outer orifice and length of VA were significantly smaller in the MD group than those in the control group (p < 0.05). Both VA patency and length were correlated with the degree of EH in the cochlea and the vestibule (p < 0.05). No difference was found between VA morphology and the degree of hearing loss (p > 0.05). CONCLUSION: The morphological characteristics of VA were found to be associated with the occurrence of MD and the degree of EH. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:3349-3354, 2024.

The Effect of Transverse Sinus Stenosis Caused by Arachnoid Granulation on Patients with Venous Pulsatile Tinnitus: A Multiphysics Interaction Simulation Investigation.

This study aimed to investigate the effect of the transverse sinus (TS) stenosis (TSS) position caused by arachnoid granulation on patients with venous pulsatile tinnitus (VPT) and to further identify the types of TSS that are of therapeutic significance for patients. Multiphysics interaction models of six patients with moderate TSS caused by arachnoid granulation and virtual stent placement in TSS were reconstructed, including three patients with TSS located in the middle segment of the TS (group 1) and three patients with TTS in the middle and proximal involvement segment of the TS (group 2). The transient multiphysics interaction simulation method was applied to elucidate the differences in biomechanical and acoustic parameters between the two groups. The results revealed that the blood flow pattern at the TS and sigmoid sinus junction was significantly changed depending on the stenosis position. Preoperative patients had increased blood flow in the TSS region and TSS downstream where the blood flow impacted the vessel wall. In group 1, the postoperative blood flow pattern, average wall pressure, vessel wall vibration, and sound pressure level of the three patients were comparable to the preoperative state. However, the postoperative blood flow velocity decreased in group 2. The postoperative average wall pressure, vessel wall vibration, and sound pressure level of the three patients were significantly improved compared with the preoperative state. Intravascular intervention therapy should be considered for patients with moderate TSS caused by arachnoid granulations in the middle and proximal involvement segment of the TS. TSS might not be considered the cause of VPT symptoms in patients with moderate TSS caused by arachnoid granulation in the middle segment of the TS.

Hemodynamic assessments of unilateral pulsatile tinnitus with jugular bulb wall dehiscence using 4D flow magnetic resonance imaging.

Background: Pulsatile tinnitus (PT) is a type of tinnitus characterized by a rhythmic sound that is synchronous with the heartbeat. One of the possible causes of PT is the jugular bulb wall dehiscence (JBWD). However, the hemodynamics of this condition are not well understood. To elucidate this issue, the present study aimed to compare the blood flow of PT patients with JBWD, PT patients with sigmoid sinus wall dehiscence (SSWD), and volunteers. Methods: A retrospective case-control study was conducted, which enrolled patients with unilateral PT who had undergone both computed tomography angiography (CTA) and four-dimensional (4D) flow magnetic resonance imaging (MRI) examinations at the Department of Otolaryngology-Head and Neck Surgery of Beijing Friendship Hospital affiliated to Capital Medical University between January 2019 and July 2023. After excluding the possible causes of PT, the patients were divided into the JBWD group and SSWD group according to the presence or absence of JBWD and/or SSWD. Finally, 11 female unilateral PT patients with JBWD (JBWD group, 11sides), 22 age- and side-matched female patients with SSWD (SSWD group, 22 sides), and 22 age-matched female volunteers (volunteer group, 36 sides) were enrolled. The area, maximum voxel velocity (Vv-max), maximum velocity (Vmax), average velocity (Vavg), and average blood flow rate (Q) were measured in the transverse sinuses (TSs), sigmoid sinuses (SSs), and jugular bulb (JB). The vortex flow pattern was also assessed. Fisher's exact test and Bonferroni correction were used for count data, with P<0.017 was considered statistically significant. Shapiro-Wilk test, one-way analysis of variance (ANOVA), Kruskal-Wallis H test, paired-samples t-test, and Wilcoxon matched-pairs signed-rank test were used for continuous variables depending on the distribution and variance of the data. The P<0.05 and corrected P<0.05 was considered statistically significant. Results: The area and Q of TSs and JB on the symptomatic side were higher than those on the contralateral side in the JBWD group (TSs: Parea=0.004, Pflow=0.002; JB: Parea=0.034, Pflow=0.018). The area was larger and velocities were lower in the JBWD group at the TSs than the SSWD group (Parea=0.004, PVv-max=0.009, PVmax=0.021, PVavg=0.026), and velocities were higher at the distal TSs and SSs than the volunteer group (TSs: PVv-max=0.042, PVmax=0.046, PVavg=0.040; SSs: PVv-max=0.007, PVmax=0.001, PVavg=0.001). At the JB, the JBWD group also had higher Vv-max than the volunteer group (P=0.012). The occurrence rate of vortex at JB in the JBWD group was higher than both the JBWD and the volunteer groups (P=0.002<0.017 and P=0.009<0.017, respectively). Conclusions: The blood flow of the intracranial venous sinus was different between the JBWD group and the SSWD group. The indicators that can differentiate include Vv-max, Vmax, Vavg, vortex, and TSs cross-sectional area.

Computed Tomography Evaluation of Unilateral Chronic Maxillary Sinusitis With Osteitis.

BACKGROUND: Computed tomography (CT) is the preferred noninvasive method for the evaluation of osteitis in chronic sinusitis. Some scholars believe that the bone changes associated with chronic sinusitis always show high attenuation (high density) and are positively correlated with the severity of the disease. However, sinus bone remodeling is a complex process that may cause high or low attenuation. There have been few reports on the spread of osteitis. Therefore, additional research on sinus CT is necessary. OBJECTIVE: To observe bony changes in chronic maxillary sinusitis (CMS) by CT and reveal the mechanism. METHODS: A retrospective study was conducted in 45 patients with unilateral CMS with bony changes in the sinus walls. The patients' clinical data and CT results were analyzed and compared between the affected and normal sides. We propose the location, involvement, attenuation, and thickness method to evaluate CMS with osteitis. RESULTS: Of the 45 patients, 40 (88.9%), 2, 12, and 7 had posterior external, medial, anterior, and superior lesions, respectively. The nasal region, sphenoid bone, palatine bone, and zygomatic arch were involved in 3, 12, 8, and 18 (40%) patients, respectively. Computed tomography indicated high attenuation in 30 (75.0%) and low attenuation in 10 (25.0%) patients; 6 (15.0%) showed new bone marrow cavities. The bone thickness was significantly different between the affected and normal sides in 40 patients (P < .001), including members of both the high- and low-attenuation groups (high-attenuation group: P < .001; low-attenuation group: P < .01). However, there was no significant difference in the thickness of the affected side between the high- and low-attenuation groups (P > .05). CONCLUSIONS: Chronic rhinosinusitis with bony changes may occur in the maxillary sinus walls and spread to adjacent bones. Both increased and decreased attenuation may occur in these circumstances. Analyzing the CT features of bone changes in unilateral CMS can improve the accuracy of disease diagnosis.

A new method for assessing transverse sinus stenosis with CT venography based on the venous trans-stenotic pressure gradient.

BACKGROUND: Evaluation of the transverse sinus stenosis (TSS) is essential for TSS-related diseases. OBJECTIVE: To investigate a new method for the quantitative assessment of TSS based on the correlation between TSS and trans-stenotic pressure gradient (TPG). METHODS: Patients with unilateral pulsatile tinnitus with or without idiopathic intracranial hypertension were retrospectively included. All patients underwent CT venography and venous manometry and were confirmed to have TSS. The cross-sectional diameter/area of TSS, the poststenotic and prestenotic segments, and the superior sagittal sinus (SSS) were measured. The degree of TSS was calculated by dividing the diameter/area of TSS by the diameter/area of the poststenotic segment (M1/M2), prestenotic segment (M3/M4), and SSS (M5/M6). Partial correlation analysis (controlling for the effect of age, sex, outflow laterality, and contralateral stenosis) was performed to evaluate the correlation between M1-M6 and the TPG. Receiver operating characteristic curve analysis of M1-M6 for diagnosing a significant TPG (≥8 mm Hg) was performed. RESULTS: Ninety-nine patients met the inclusion criteria. The partial correlation coefficients between M1-M6 and the TPG were 0.60, 0.61, 0.43, 0.48, 0.39, and 0.54, respectively. The areas under the curve (AUCs) of M1-M6 for diagnosing a significant TPG were 0.81, 0.86, 0.68, 0.69, 0.64, and 0.72, respectively. The AUC of M2 was significantly larger than that of M3 (P=0.002), M4 (P<0.001), M5 (P=0.001), and M6 (P<0.001). CONCLUSIONS: Quantitatively assessing TSS by taking the ratio of the cross-sectional area of TSS to that of the poststenotic segment might be a more efficient method for predicting the TPG.

Correlation between grading methods of the cochlear endolymphatic hydrops and hearing loss in meniere's disease using three-dimensional real inversion recovery sequences.

BACKGROUND: The grading of intracochlear endolymphatic hydrops (EH) in Meniere's disease (MD) varies and lacks uniformity. AIMS: To compare the grading consistency and correlation between different grade methods of intracochlear EH and hearing loss. MATERIALS AND METHODS: Thirty-one patients diagnosed with MD underwent gadolinium-enhanced magnetic resonance imaging. Two radiologists graded the cochlea EH according to M1, M2, M3, or M4. We analysed the grading consistency and correlation between the EH degrees and hearing loss. RESULTS: The weighted kappa coefficients for inter-observer and intra-observer agreements for grading using M1 were good, whereas those for M2, M3, and M4 are excellent (all p < 0.001). The cochlear EH degree based on M2 was correlated with the low-to-mid frequencies, high frequencies, full frequencies, and MD clinical stage (all p < 0.05). The degrees based on M1, M3, M4 were only relevant to some of the 4 items. CONCLUSIONS: The grading consistency of M2, M3, M4 is relatively higher than that of M1, and M2 shows the strongest correlation with hearing loss. SIGNIFICANCE: Our results provide a more accurate method for assessing the clinical severity of MD.

Comparative study of the sensitivity of ultra-high-resolution CT and high-resolution CT in the diagnosis of isolated fenestral otosclerosis.

PURPOSE: To compare the diagnostic sensitivity of ultra-high-resolution computed tomography (U-HRCT) and HRCT in isolated fenestral otosclerosis (IFO). METHODS: A retrospective analysis was conducted on 85 patients (85 ears) diagnosed with IFO between October 2020 and November 2022. U-HRCT (0.1 mm thickness) was performed for 20 ears, HRCT (0.67 mm thickness) for 45 ears, and both for 20 ears. The images were evaluated by general radiologists and neuroradiologists who were blinded to the diagnosis and surgical information. The diagnostic sensitivity of U-HRCT and HRCT for detecting IFO was compared between the two groups. RESULTS: Excellent inter-observer agreement existed between the two neuroradiologists (Cohen's κ coefficient 0.806, 95% CI 0.692-0.920), with good agreement between the general radiologists (Cohen's κ coefficient 0.680, 95% CI 0.417-0.943). U-HRCT had a sensitivity of 100% (40/40 ears) for neuroradiologists and 87.5% (35/40 ears) for general radiologists, significantly higher than HRCT (89.2% [58/65 ears] for neuroradiologists; 41.5% [27/65 ears] for general radiologists) (p = 0.042, p' < 0.000). General radiologists' sensitivity with HRCT was significantly lower compared to neuroradiologists (p < 0.000), but no significant difference was observed when general radiologists switched to U-HRCT (p = 0.152). Among the 20 ears that underwent both examinations, U-HRCT detected lesions smaller than 1 mm in 5 ears, whereas HRCT's sensitivity for neuroradiologists was 40% (2/5 ears), significantly lower than for lesions larger than 1 mm (93.3%, 14/15 ears, p = 0.032). CONCLUSION: U-HRCT exhibits higher sensitivity than HRCT in diagnosing IFO, suggesting its potential as a screening tool for suspected otosclerosis patients. CRITICAL RELEVANCE STATEMENT: Ultra-high-resolution computed tomography has the potential to become a screening tool in patients with suspected otosclerosis and to bridge the diagnostic accuracy gap between general radiologists and neuroradiologists. KEY POINTS: • U-HRCT exhibits higher sensitivity than HRCT in the diagnosis of IFO. • U-HRCT has a significant advantage in the detection of less than 1 mm IFO. • U-HRCT has the potential to be used for screening of patients with suspected otosclerosis.

Flow patterns in the venous sinus of pulsatile tinnitus patients with transverse sinus stenosis and underlying vortical flow as a causative factor.

BACKGROUND: Transverse sinus stenosis (TSS) is commonly found in Pulsatile Tinnitus (PT) patients. Vortex flow is prominent in venous sinus with stenosis, and so it is important to determine the distribution and strength of the vortical flow to understand its influence on the occurrence of PT. METHODS: In this study, by using computational fluid dynamics for hemodynamic analysis in patient-specific geometries based on Magnetic Resonance Imaging (MRI), we have investigated the blood flow within the venous sinus of 16 subjects with PT. We have employed both laminar and turbulent flow models for simulations, to obtain (i) streamlines of velocity distribution in the venous sinus, and (ii) pressure distributions of flow patterns in the venous sinus. Then, hemodynamic analysis in the venous sinus recirculation zone was carried out, to determine the flow patterns at the junction of transverse sinuses and sigmoid sinuses. Finally, we have proposed a new model for turbulence evaluation based on the regression analysis of anatomic and hemodynamics parameters. RESULTS: Correlation analysis between the anatomical parameters and the hemodynamic parameters has shown that stenosis at the transverse sinus was the main factor in the local hemodynamics variation in the venous sinus of patients; in this context, it is shown that vorticity can be used as a prime indicator of the severity of the stenosis function. Our results have shown a significant correlation between the vorticity and the stenotic maximum velocity (SMV) (r = 0.282, p = 0.004). Then, a parameterized prediction model is proposed to determine the vorticity in terms of flow and anatomic variables, termed as the turbulence eddy prediction model (TEP model). Our result have shown that the TEP model is sensitive to the dominant flow distribution, with a high correlation to the flow-based vorticity (r = 0.809, p = 0.009). CONCLUSIONS: The quantification of the vorticity (as both vorticity and MVV) in the downstream of TSS could be a marker for indication of turbulent energy at the transverse-sigmoid sinus, which could potentially serve as a hemodynamic marker for the functional assessment of the PT-related TSS.