Hydroacoustic analysis and extraluminal compression surgical insights of venous pulsatile tinnitus

Spontaneous otoacoustic emission as a novel method to screen pulsatile tinnitus caused by sigmoid sinus wall abnormalities: a prospective study

OBJECTIVE

To evaluate the diagnostic potential of spontaneous otoacoustic emissions (SOAE), distortion product otoacoustic emissions (DPOAE), and pure-tone audiometry (PTA) in patients with pulsatile tinnitus (PT) caused by sigmoid sinus wall anomalies (SSWA).

METHODS

This study included 20 PT patients and 20 matched healthy controls. SOAE, DPOAE, and PTA were assessed before and after compression of the internal jugular vein. Statistical analysis included paired t-tests to compare differences in SOAE amplitude, DPOAE signal-to-noise ratios, and PTA thresholds, while independent t-tests assessed age differences, and one-way ANOVA evaluated mean PTA thresholds.

RESULTS

SOAE amplitudes were significantly higher in ipsilesional ears compared to contralesional and control ears. DPOAE showed a significant difference in 0.5 kHz S/N-ratio between ipsilesional and contralesional ears. PTA revealed higher thresholds in ipsilesional ears at low frequencies, with differences decreasing after compression.

CONCLUSION

Besides radiological modalities, SOAE is a sensitive tool for diagnosing and assessing the severity of PT in patients with SSWA, with DPOAE and PTA providing supplementary information. These findings suggest a multimodal approach for the diagnosis of PT related to SSWA.

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.

Resurfacing Dehiscence(s) Without Reducing Diverticulum Effectively Silences Pulsatile Tinnitus: Novel Surgical Techniques for Diverticulum and Intraoperative Microphone Monitoring

OBJECTIVE

To emphasize the surgical importance of addressing dehiscence over diverticulum in resolving pulsatile tinnitus (PT) in patients with sigmoid sinus wall anomalies (SSWAs) and investigate anatomical differences.

STUDY DESIGN

Retrospective data analysis.

SETTING

Multi-institutional tertiary university medical centers.

PATIENTS

Fifty participants (dehiscence/diverticulum, 29:21 cases) with SSWA-associated PT were included in the study. All 21 diverticulum participants underwent surgical intervention.

INTERVENTIONS

1) Surgical intervention with novel techniques monitored by intraoperative microphone. 2) Radiologic and ophthalmologic imaging methods.

MAIN OUTCOME MEASURES

Quantitative and qualitative preoperative and postoperative alterations of PT and anatomical differences between dehiscence and diverticulum.

RESULTS

Addressing dehiscence overlying diverticulum and sigmoid sinus wall dehiscences significantly reduced visual analog score and Tinnitus Handicap Inventory ( p < 0.01). Sinus wall reconstruction led to substantial PT sound intensity reduction in the frequency range of 20 to 1000 Hz and 20 to 500 Hz (paired-sample t test, p < 0.01). Diploic vein analysis showed a significant positive correlation in 85.7% of the diverticulum cohort compared with the dehiscence cohort ( p < 0.01). Eight percent of the participants exhibited papilledema, which was limited to the dehiscence cohort.

CONCLUSION

1) Effective reduction of PT can be achieved by addressing all dehiscences, including those overlying the diverticulum, without the need to exclude the diverticulum. 2) Diploic vein may involve in the formation of diverticulum, and loss of dura mater and vascular wall thickness are observed at the SSWA locations.

Multiphysics Interaction Analysis of the Therapeutic Effects of the Sigmoid Sinus Wall Reconstruction in Patients with Venous Pulsatile Tinnitus

Sigmoid sinus wall dehiscence (SSWD) is an important etiology of venous pulsatile tinnitus (VPT) and is treated by sigmoid sinus wall reconstruction (SSWR). This study aimed to investigate the therapeutic effects of the different degrees of SSWR and the prognostic effect in patients with VPT. Personalized models of three patients with SSWD (control), 3/4SSWD, 1/2SSWD, 1/4SSWD, and 0SSWD were reconstructed. A multiphysics interaction approach was applied to elucidate the biomechanical and acoustic changes. Results revealed that after SSWR, the average pressure of venous vessel on the SSWD region reduced by 33.70 ± 12.53%, 35.86 ± 12.39%, and 39.70 ± 12.45% (mean ± SD) in three patients with 3/4SSWD, 1/2SSWD, and 1/4SSWD. The maximum displacement of the SSWR region reduced by 25.91 ± 30.20%, 37.20 ± 31.47%, 52.60 ± 34.66%, and 79.35 ± 18.13% (mean ± SD) in three patients with 3/4SSWD, 1/2SSWD, 1/4SSWD, and 0SSWD, with a magnitude approximately 10^-3 times that of the venous vessel in the SSWD region. The sound pressure level at the tympanum reduced by 23.72 ± 1.91%, 31.03 ± 14.40%, 45.62 ± 19.11%, and 128.46 ± 15.46% (mean ± SD). The SSWR region was still loaded with high stress in comparison to the surrounding region. The SSWR region of the temporal bone effectively shielded the high wall pressure and blocked the transmission of venous vessel vibration to the inner ear. Patients with inadequate SSWR still had residual VPT symptoms despite the remission of VPT symptoms. Complete SSWR could completely solve VPT issues. High-stress distribution of the SSWR region may be the cause of the recurrence of VPT symptoms.

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.

Evidence of air-conduction transmission pathway and strategized transtemporal operative techniques for venous pulsatile tinnitus: Combining water occlusion test and operative sensing applications

OBJECTIVES

(1) To establish evidence of the transmission pathway of venous pulsatile tinnitus (PT) associated with sigmoid sinus wall anomalies (SSWAs) and (2) quantify the efficacy of transtemporal surgery.

METHODS

This retrospective study included 33 surgical cases of PT associated with SSWAs and 15 controls with venous PT without SSWAs. Quantitative water occlusion test (q-WOT) and imaging data were acquired for preoperative evaluation prior to strategized transtemporal osteovascular reconstruction surgery. A condenser microphone and hydrophone were intraoperatively deployed to assess and monitor in vivo amplitude variations of the PT in eight participants.

RESULTS

A total of 23 (69.6%) participants with SSWA responded to the q-WOT with a median solution volume of 1.3 (1.1/1.6), which significantly differed from that observed in controls (p < 0.01). The change in the operative peak amplitude of the acoustic data was statistically significant (p < 0.01), from a median of 57.6 (55.5/57.9) dB SPL to 34.3 (33.4/38.8) dB SPL.

CONCLUSION

Intraoperative application of acoustic sensors revealed that PT associated with SSWAs is predominantly transmitted via the air-conduction pathway. If objective findings such as q-WOT and sensing applications suggest that the transmission of venous PT is involved in middle ear air conduction, the reconstruction technique should be prioritized; if less involvement of middle ear air-conduction is indicated, addressing flow pathologies may be imperative for resolving venous PT.

LEVEL OF EVIDENCE

4.