Transmastoid reshaping of the sigmoid sinus: preliminary study of a novel surgical method to quiet pulsatile tinnitus of an unrecognized vascular origin

Tailored re-roofing technique for pulsatile tinnitus caused by sigmoid sinus dehiscence or diverticulum

Background

Sigmoid sinus diverticulum/dehiscence (SSD) is one of the treatable causes of venous pulsatile tinnitus. It can be diagnosed using temporal bone computed tomography (CT) or magnetic resonance angiography/venography (MRA). In cases where patients find their symptoms intolerable, surgical treatment is typically preferred. Here, we have presented a novel surgical technique involving sigmoid sinus re-roofing and have analyzed its feasibility.

Methods

Between January 2020 and July 2023, approximately 150 patients with pulsatile tinnitus were evaluated at two different tertiary hospitals. Of these, 12 patients were diagnosed with SSD, and seven underwent surgical treatment. Five patients were treated with tailored reroofing (TRR) of the sigmoid sinus and two with transmastoid resurfacing (MRS) of the sigmoid sinus. We compared the Korean tinnitus handicap inventory (K-THI) score, pure tone audiogram (PTA) threshold, and CT findings before and a month after surgeries for these two techniques. The operation time was also analyzed.

Results

In TRR cases, the K-THI score reduced from 55.0 ± 31.4 preoperatively to 4.0 ± 3.0 postoperatively, and the SSD was well-repositioned and covered by a bone chip postoperatively. In MRS cases, the K-THI score reduced from 41.0 ± 9.9 preoperatively to 15.0 ± 21.2 postoperatively, and the SSD was well-covered with bone cement postoperatively. The average surgical time of five TRR and two MRS cases were 77.5 ± 32.5 and 174.0 ± 75.0 min, respectively. No complications were noted.

Conclusions

Despite the insufficient number of cases, we noted that TRR requires a reasonable amount of time, involves a smaller incision, and may provide favorable outcomes compared to conventional MRS in cases of pulsatile tinnitus associated with SSD.

Level of evidence

IV.

An anatomical study of the sigmoid sinus artery: Application to the transmastoid approach

INTRODUCTION

We aimed to investigate the morphological features of the artery that traverse the sigmoid sinus's lateral surface and to discuss this structure's clinical relevance.

METHODS

Ten sides from five cadaveric Caucasian heads were used for gross anatomical dissection to investigate the morphological features of the sigmoid sinus artery (SSA), and additional five sides were used for histological observation.

RESULTS

The SSA was found on eight out of ten sides (80%). The mean diameter of the SSA was 0.3 mm. The mean distance from the tip of the mastoid process to the artery was 20.3 mm. Histological observation identified extradural and intradural courses of SSA. The intradural course was further categorized into protruding and non-protruding types. In the protruding type, the SSA traveled within the dura but indented into the bone, making it more or less an intraosseous artery. In the non-protruding type, the SSA traveled within the dura but did not protrude into the bone but rather indented into the lumen of the SS. In all sections, both intradural and extradural courses were identified simultaneously.

CONCLUSIONS

When the mastoid foramen is observed, it does not always only carry an emissary vein but also an artery. The SSA could be considered a "warning landmark" during bone drilling for the transmastoid approach.

Surgical Outcomes of Sigmoid Sinus Resurfacing for Pulsatile Tinnitus: The Predictive Value of the Water Occlusion Test and Imaging Studies

OBJECTIVES

Sigmoid sinus resurfacing (SS-R) is one of the most effective surgical treatments for patients with pulsatile tinnitus (PT) originating from anatomical variants of the vascular walls in the temporal bone. This study aimed to provide updated information on the clinical outcomes of SS-R and evaluate the efficacy of the water occlusion test (WOT) as an additional diagnostic modality.

METHODS

We retrospectively reviewed medical records including tinnitus questionnaires, temporal bone computed tomography (TBCT) scans, audiologic tests, and preoperative WOT.

RESULTS

from patients who underwent SS-R.

RESULTS

In total, 26 patients were included in the study. The mean age was 44 years, and the mean symptom duration was 3 months. Fourteen patients (53.8%) were completely cured, seven (26.9%) significantly improved, and five (19.2%) remained stable. The mean visual analog scale loudness score decreased from 5.26 to 1.34 (P<0.001) and the mean Tinnitus Handicap Inventory score also improved from 50.23 to 5.5 (P<0.001) after SS-R surgery. In 10 patients with discrepancies between the preoperative TBCT and intraoperative findings, WOT showed a significant additive effect in predicting surgical outcomes. No patients experienced severe intraoperative or postoperative complications during the entire follow-up period.

CONCLUSION

SS-R provides significant symptom improvement in patients with sigmoid sinus dehiscence who had a positive WOT without other sigmoid sinus variants. A combined diagnostic approach with TBCT, WOT, and intraoperative findings is crucial for achieving better surgical outcomes in patients with PT caused by sigmoid sinus variants.

Causes and outcomes of revision surgery in subjects with pulsatile tinnitus

INTRODUCTION

Once the underlying pathology has been identified, pulsatile tinnitus (PT) can be treated successfully with surgical or interventional management. However, some patients experience residual or recurrent symptoms following initially successful surgical treatment, and require revision surgery or additional procedures. Here, we report a case series of patients who had undergone revision surgery or interventional treatment, and suggest possible ways of minimizing the need for revision.

METHODS

Between January 2014 and March 2023, a total of seven subjects underwent revision surgery or interventional treatment for persistent or recurrent PT after initial surgical treatment. Demographic data, reasons for revision, and changes in symptoms before and after revision were analyzed retrospectively. Temporal bone computed tomographic angiography images were reviewed to identify the causes and reasons for revision.

RESULTS

Of the seven subjects, six underwent sigmoid sinus (SS) resurfacing/reshaping due to ipsilateral diverticulum (Div) or dehiscence (Deh), and one underwent jugular bulb (JB) resurfacing due to a high-riding JB with bony Deh. Of the five subjects who underwent revision SS surgery due to recurrent SS-Div or SS-Deh, three showed marked resolution of PT, while the other two showed partial improvement of the symptoms. One subject who underwent revision JB resurfacing, and another who underwent additional transarterial embolization for a concurrent ipsilateral dural arteriovenous fistula, reported marked improvement of PT.

DISCUSSION

The possibility of recurrence should be taken into account when performing surgical intervention in patients with PT. The likelihood of recurrence can be minimized through a comprehensive evaluation to identify possible multiple etiologies, and through the use of durable materials and appropriate surgical methods.

Radiographic Sigmoid Sinus Wall Abnormalities and Pulsatile Tinnitus: A Case-Control Study

OBJECTIVE

Compare incidence of sigmoid sinus wall abnormalities (SSWAs) and other radiographic abnormalities in patients with pulsatile tinnitus (PT) versus controls.

STUDY DESIGN

Retrospective case-control.

SETTING

Tertiary referral center.

PATIENTS

Adults with PT and high-resolution computed tomography imaging were compared with adults undergoing cochlear implant workup including high-resolution computed tomography imaging.

MAIN OUTCOME MEASURES

Incidence of SSWA in PT cohort (n = 141) compared with control (n = 149, n = 298 ears). Secondary outcome measures included differences in demographics and in other radiographic abnormalities between cohorts.

RESULTS

Patients with PT had a higher incidence of SSWA (34% versus 9%, p < 0.001) and superior canal dehiscence (23% versus 12%, p = 0.017) than controls. Spearman product component correlations demonstrated that ipsilateral PT was weakly associated with SSWA ( r = 0.354, p < 0.001). When SSWA was present in the PT cohort (n = 48 patients, n = 59 ears), in 31 cases (64.6%), the SSWA correlated with PT laterality (e.g., left SSWA, left PT); in 12 (25.0%), SSWA partially correlated with PT laterality (e.g., bilateral SSWA, right PT); and in 5 (10.4%), the SSWA did not correlate with PT laterality (e.g., right SSWA, left PT).

CONCLUSIONS

For our patients with both PT and SSWA, the SSWA is likely a contributing factor in approximately 65% of cases. For a third of patients with PT and concomitant SSWA, the association between the two is either not causative or not solely causative. Surgeons counseling patients with PT and SSWA may be optimistic overall regarding sigmoid resurfacing procedures but must appreciate the possibility of treatment failure, likely because of untreated comorbid conditions.

Outcomes in Managing Vascular Tinnitus: Institutional Experience and Review of 6-Year Literature

To evaluate the outcomes in patients of vascular tinnitus managed at our institute. The clinical data of all patients diagnosed with pulsatile tinnitus from January 2014 to April 2022 and managed at AIIMS, Bhubaneswar, was retrospectively reviewed. The diagnosis, treatment and outcomes were analyzed. A 6-year literature review was performed from March 2015 to April 2021. Our series discusses managing eleven cases of vascular tinnitus with varied aetiology and their outcomes. Out of the eleven cases, eight patients underwent surgical or radiological intervention, and seven had complete resolution of symptoms. Of the eleven patients, three had partial resolution. The 6-year literature review revealed sigmoid and transverse sinus as the most common causative anatomical sites for pulsatile tinnitus. Amongst those who received an intervention, 83.56% of the patients had complete resolution of symptoms. Vascular tinnitus can be cured if the exact vessel causing it is localized. Clinical suspicion is based on the character of tinnitus and patient history. A careful evaluation of the head and neck sites for any vascular anomaly that can cause pulsatile tinnitus must be done. Radiology demonstrates treatable causes of it. It delineates the aberrant anatomical variations that can lead to this disturbing aetiology. Treatable causes are best addressed, and pathology should be taken care of. A multidisciplinary team comprising ENT surgeons, audiologists and interventional radiologists must identify and treat the pathology.

Retroauricular/Transcranial Color-Coded Doppler Ultrasound Approach in Junction With Ipsilateral Neck Compression on Real-Time Hydroacoustic Variation of Venous Pulsatile Tinnitus

Alterations in dural venous sinus hemodynamics have recently been suggested as the major contributing factors in venous pulsatile tinnitus (PT). Nevertheless, little is known about the association between real-time alterations in hemodynamics and the subjective perception of venous PT. This study aimed to investigate the hydroacoustic correlations among diverticular vortices, mainstream sinus flow, and PT using various Doppler ultrasound techniques. Nineteen venous PT patients with protrusive diverticulum were recruited. The mainstream sinus and diverticular hemodynamics before and after ipsilateral internal jugular vein (IJV) compression were investigated using an innovative retroauricular color-coded Doppler (RCCD) method to examine the correlation between the disappearance of PT and hemodynamic alterations. To reveal the hydroacoustic characteristics of disparate segments of venous return, a computational fluid dynamics (CFD) technique combined with the transcranial color-coded Doppler method was performed. When the ipsilateral IJV was compressed, PT disappeared, as the mean velocity of mainstream sinus flow and diverticular vortex decreased by 51.2 and 50.6%, respectively. The vortex inside the diverticulum persisted in 18 of 19 subjects. The CFD simulation showed that the flow amplitude generated inside the transverse–sigmoid sinus was segmental, and the largest flow amplitude difference was 20.5 dB. The difference in flow amplitude between the mainstream sinus flow and the diverticular flow was less than 1 dB. In conclusion, the sensation of PT is closely associated with the flow of kinetic energy rather than the formation of a vortex, whereby the amplitude of PT is correlated to the magnitude of the flow velocity and pressure gradient. Additionally, the range of velocity reduction revealed by the RCCD method may serve as a presurgical individual baseline curative marker that may potentially optimize the surgical outcomes.

Effects of Different Degrees of Extraluminal Compression on Hemodynamics in a Prominent Transverse-Sigmoid Sinus Junction

Objectives

To simulate hemodynamic changes after extraluminal compression in pulsatile tinnitus (PT) patients with a prominent transverse-sigmoid sinus junction (PTSJ).

Methods

One patient-specific case was reconstructed based on computed tomography venography (CTV) images of a PT patient. The compression degree served as a new index in this study. Cases with 10, 20, 30, 40, 50, 60, 70, 80, and 90% of the compression degree of the control subject were constructed. Steady-state computational fluid dynamics (CFD) were assessed. The wall pressure distribution, wall maximum pressure (P_max) and flow pattern (velocity streamlines and velocity vector) of the PTSJ were calculated to evaluate hemodynamic differences among all cases.

Results

With increasing compression, the wall pressure at the compression point and downstream of the PTSJ decreased but increased upstream. When the compression degree exceeded 70%, the upstream pressure increased significantly. Above 50% compression, the blood flow pattern downstream of the sigmoid sinus tended to spiral, especially after 80% compression. Beyond 60% compression, the blood flow pattern under the compression axis became more medial.

Conclusion

Mechanical compression of PTSJ changes wall pressure and blood flow patterns. The degree of compression should be carefully observed to avoid possible complications or reoccurrence.

Transtemporal Sigmoid Sinus Decompression: A Novel Surgical Procedure for the Treatment of Idiopathic Pulsatile Tinnitus

OBJECTIVE

Idiopathic pulsatile tinnitus (IPT) is associated with high patient morbidity although treatment methods remain unsatisfactory. In the present study, the transtemporal sigmoid sinus decompression is used in the treatment of idiopathic pulsatile tinnitus.

STUDY DESIGN

Retrospective case study.

SETTING

Tertiary referral center.

PATIENTS

From 2005 to 2020, 287 patients presented with a complaint of pulsatile tinnitus. After exclusion criteria, 25 patients were diagnosed with IPT. Those patients underwent treatment and were included in a retrospective study.

INTERVENTIONS

Following failed conservative therapies, the primary author performed a transtemporal sigmoid sinus decompression surgery on the patients under general anesthesia.

MAIN OUTCOME MEASURES

Long-term resolution of IPT was measured using the Tinnitus Handicap Inventory (THI). Outcome measurements were taken preoperatively, immediately postoperatively, three months postoperatively, and the status of all 25 patients is known at the time of this study.

RESULTS

Transtemporal sigmoid sinus decompression was performed on 25 patients (mean age: 51.7 years, 80.0% female). Out of the 25 patients, 23 (92.0%) patients experienced complete resolution of their IPT. Statistically significant differences based on preoperative THI (mean THI: 4.19) were evident immediately after surgery (mean THI: 1.31; p < 0.001), at 3 months postoperatively (mean THI: 1.19; p < 0.001), and over a mean follow-up time of 68.7 months (range, 3-168 months) (mean THI: 1.38; p < 0.001). Out of the two patients considered unsuccessful, Case 21 experienced a partial resolution. No major postoperative complications occurred.

CONCLUSIONS

Transtemporal sigmoid sinus decompression is a safe and effective surgical procedure demonstrated to give near total resolution in properly selected patients and provides long-term relief for patients with IPT.

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.

Posterior Skull Base Anatomy and Pathology

A posterior skull base lesion is an uncommon radiological finding that may be noted incidentally or during targeted imaging of patients with clinical symptoms attributable to the lesion. It may be inflammatory or neoplastic in etiology, or may simply be an anatomic variant or a "don't-touch" lesion that should not be misinterpreted as something more ominous. A systematic approach to the evaluation of the posterior skull base is therefore required in order to differentiate lesions requiring immediate attention from those requiring a less urgent course of action or none at all. This review will focus on the imaging features of pathologic conditions that are more commonly encountered in posterior skull base CT and MR examinations.

Prevalence, Surgical Management, and Audiologic Impact of Sigmoid Sinus Dehiscence Causing Pulsatile Tinnitus

OBJECTIVE

To evaluate the prevalence, surgical management, and audiologic impact of pulsatile tinnitus caused by sigmoid sinus dehiscence.

STUDY DESIGN AND SETTING

Retrospective chart review at a tertiary care hospital.

PATIENTS

Adults with unilateral pulsatile tinnitus attributable to sigmoid sinus dehiscence who underwent resurfacing between January 2010 and January 2020.

INTERVENTIONS

Transmastoid sigmoid resurfacing.

MAIN OUTCOME MEASURES

Resolution of pulsatile tinnitus; audiologic outcomes; complications; tinnitus etiologies.

RESULTS

Nineteen patients (89.4% women) had surgery for suspected sigmoid sinus dehiscence. The mean dehiscence size was 6.1 mm (range, 1-10.7 mm). Eight patients had concurrent sigmoid sinus diverticulum and one patient also had jugular bulb dehiscence. Only two patients (10.5%) had the defect identified by radiology. Low-frequency pure-tone average, measured at frequencies of 250 and 500 Hz, showed a significant median improvement of 8.8 dB following resurfacing (18.8 dB versus 10.0 dB, p = 0.02). The majority of patients had complete resolution of pulsatile tinnitus (16/19, 84.2%). Of those without complete resolution, two patients had partial response and one patient had no improvement. There were no significant complications. Of 41 consecutively tracked patients with a pulsatile tinnitus chief complaint, sigmoid pathology represented 32% of cases.

CONCLUSIONS

Sigmoid sinus dehiscence represents a common vascular cause of pulsatile tinnitus that, if properly assessed, may be amenable to surgical intervention. Sigmoid sinus resurfacing is safe, does not require decompression, and may improve low-frequency hearing. Radiographic findings of dehiscence are often overlooked without a high index of clinical suspicion. Its relationship with transverse sinus pathology and idiopathic intracranial hypertension remain unclear.

Hemodynamic Changes in the Sigmoid Sinus of Patients With Pulsatile Tinnitus Induced by Sigmoid Sinus Wall Anomalies

OBJECTIVE

This study is to investigate the hemodynamic changes of pulsatile tinnitus (PT) patients induced by sigmoid sinus wall anomalies (SSWA).

STUDY DESIGN

Prospective study.

SETTING

Tertiary referral university hospital.

PATIENTS

Fifteen unilateral PT patients with SSWA identified on computed tomography images and surgery and 15 age-, sex-, and body mass index-matched healthy volunteers underwent velocity-encoded, cine magnetic resonance imaging.

INTERVENTION

Hemodynamic data in sigmoid sinus were obtained from velocity-encoded, cine magnetic resonance imaging, and compared between PT patients and controls.

MAIN OUTCOME MEASURES

Heart rate was recorded. Cross-sectional area (CSA), peak positive velocity (PPV), average positive flow volume per beat (APFV/beat), average flow volume per beat (AFV/beat), peak negative velocity (PNV), and average negative flow volume per beat (ANFV/beat) were measured. Average flow volume per minute (AFV/min), average positive flow volume per minute (APFV/min), average negative flow volume per minute (ANFV/min), average positive velocity (APV), average negative velocity (ANV), and regurgitation fraction (RF) were calculated.

RESULTS

APV at PT side of patients was 13.4 ± 3.3 cm/s, which was significantly slower than that at corresponding side of controls (15.8 ± 2.6 cm/s). PNV and RF at PT side of patients were 21.0 ± 15.4 cm/s and 2.4% respectively, which were significantly higher than those values at corresponding side of controls (both of them were 0). HR, CSA, PPV, APFV/beat, APFV/min, AFV/beat, AFV/min, ANV, ANFV/beat, and ANFV/min were 69.8 ± 9.4 beat/min, 48.4 ± 17 mm, 31.4 ± 5.9 cm/s, 5.4 ± 1.8 ml/beat, 373.9 ± 117.7 ml/min, 5.1 ± 2.0 ml/beat, 352.0 ± 134.6 ml/min, 2 (0-4.9) cm/s, 1 (0-2.7) ml/beat, and 4.1 (0-141.3) ml/min at PT side of patients, and 67.4 ± 7.8 beat/min, 38.2 ± 18 mm, 29.9 ± 3.9 cm/s, 5.3 ± 2.0 ml/beat, 350.3 ± 125.3 ml/min, 5.1 ± 1.9 ml/beat, 340.5 ± 117.9 ml/min, 0 (0-2.1) cm/s, 0 (0-0.8) ml/beat, and 0 (0-55.4) ml/min at corresponding side of controls. These hemodynamics were not significantly different between groups.

CONCLUSION

APV, PNV, and RF changes take place in SSWA patients, which may be associated with the occurrence of PT and have the potential value to improve accurate etiological diagnosis and predict treatment success.

Hydroacoustic analysis and extraluminal compression surgical insights of venous pulsatile tinnitus

OBJECTIVE

This study aimed to quantitatively and qualitatively evaluate the hydroacoustic changes from "presence" to "disappearance" of pulsatile tinnitus (PT) with the extraluminal compression surgical technique. The recent issues of concern pertaining to the hydroacoustic characteristics of sigmoid sinus wall anomalies and distal transverse sinus stenosis (dTSS) were discussed.

METHODS

This study was based on a retrospective case series. Seventy-seven patients with PT and transverse-sigmoid sinus enlargement with or without transverse-sigmoid sinus junction anomalies and transverse sinus stenosis (TSS) who had undergone extraluminal compression surgery under local anesthesia were included. Management of intractable intraoperative challenges and techniques for reversal extraluminal compression were introduced. Anatomical measurements, intraoperative color-coded Doppler ultrasonography, spectro-temporal analysis, and computational fluid dynamics were employed to analyze the hydroacoustic characteristics of PT.

RESULTS

The efficacy of the extraluminal compression technique was evident with the significant reduction in peak turbulent kinetic energy, vorticity, and mean pressure gradient at the transverse-sigmoid junction, resulting in over 20% reduction in PT amplitude. dTSS is a common finding in patients with PT exhibiting transverse-sigmoid sinus enlargement. Patients with dTSS presented with significant differences in hemodynamic characteristics as compared to those without. Linear regression analysis showed that the flow disturbance (turbulent kinetic energy and vorticity) was closely associated with the degree of dTSS, whereas the flow amplitude was not related to the degree or location of TSS. Low-pulsatory vortex flow at the transverse-sigmoid junction was visualized during an intraoperative color-coded Doppler examination, and the displayed low-frequency PT sound corresponded to the patients' subjective perception of PT.

CONCLUSION

(1) A reduction of over 20% of the flow-induced noise is the therapeutic goal of extraluminal compression technique. Since reductions in the magnitude of hemodynamic parameters, including turbulent kinetic energy, vorticity, and mean pressure gradient, render the flow-induced noise inaudible, besides sigmoid sinus wall anomalies, it is likely that PT develops from the aggregation of flow-based pathologies. (2) Although dTSS and diverticulum may greatly affect the hemodynamics at the transverse-sigmoid junction, in contrast to dehiscence, dTSS and diverticulum may not be the limiting factors for PT development.

Transtemporal Venous Decompression for Idiopathic Venous Pulsatile Tinnitus

Objective To evaluate the clinical characteristics and present surgical outcomes of transtemporal venous decompression technique in the treatment of pulsatile tinnitus (PT).

Study Design This is a prospective cohort study.

Setting This study was done at the tertiary private neurotologic skull base clinic.

Participants The primary author, between March 2012 and February 2013, evaluated 55 patients with the complaint of PT. Seven out of the 55 patients were diagnosed with severe, unrelenting idiopathic pulsatile tinnitus (IPT), and were placed into the study. These seven patients had temporal bone computed tomography, magnetic resonance imaging, arteriogram, videonystagmography, electrocochleography, and lumbar puncture based on the symptoms. All the seven patients underwent transtemporal venous decompression surgery.

Main Outcome Measure Resolution of PT was determined as the primary outcome measure.

Results Six out of seven patients had complete resolution of their PT immediately after surgery and at 3 to 4 years follow-up. One patient developed intracranial hypertension after 3 months requiring ventriculoperitoneal shunt, which resolved PT as well. No complications occurred.

Conclusion A significant subset of the PT patient population has known reversible causes. The more common includes conductive hearing loss, superior canal dehiscence, benign intracranial hypertension, jugulosigmoid venous anomalies, stapedial myoclonus, etc. There exists a subset of patients who have IPT. Transtemporal venous decompression is a surgical technique that can be employed to give patients with IPT long-term relief.

Hemodynamic study of the therapeutic effects of the different degrees of sigmoid sinus diverticulum reconstruction on patients

Sigmoid sinus diverticulum (SSD) is a common pathophysiology of pulsatile tinnitus (PT) and mainly treated by SSD reconstruction surgery. The degree of reconstruction is an important indicator of SSD reconstruction surgery, but its impact on the effect of SSD reconstruction is unclear. This study aimed to clarify the effect of the degree of SSD reconstruction on diverticulum reconstruction surgical treatment. One patient-specific case (control subject) was reconstructed based on the computed tomography angiography (CTA) images of patients with PT. The SSD reconstruction degree was used as a new index in this study. And the case of 30% (case 1), 60% (case 2), and 100% (case 3) of the diverticulum reconstruction degree of control subject were constructed. Transient-state computational fluid dynamics was performed. Wall pressure distribution, wall average pressure (P_avg) of SSD, flow pattern (velocity streamlines and velocity vector), wall shear stress (WSS) and averaged WSS (WSS_avg) were calculated and used in evaluating the hemodynamic differences among the DRD cases. Results demonstrated that change in SSD pressure was not linear with increase in DRD. The DRD that reached 60% of the original diverticulum was effective. At the peak point of the inlet boundary condition (T1 = 0.22s), the P_avg of SSD had a nonlinear change (control subject, 126.967 Pa vs. case 1, 126.274 Pa vs. case 2, 106.897 Pa vs. case 3, 94.116 Pa). Flow vorticity decreased gradually, and the smoothness of the streamlines increased with DRD. WSS_avg slightly changed with increasing DRD. The high-speed flow blood hit the diverticulum entrance and then swirled to hit the area of the sigmoid sinus wall abnormal. It was concluded that flow patterns related to PT differ with DRD. In diverticulum reconstruction surgery, there is a threshold value, and only when the DRD exceeds this value (60% or 70% or 80%), it will have a noticeable effect. In this study, DRD should at least reach 60% of the original diverticulum. When DRD is insufficient, hemodynamic change in the diverticulum is small, and the PT may have remained. SSD may be caused by high-speed blood flow.

Patterns of audiometric threshold shifts from pulsatile tinnitus due to sigmoid sinus wall anomalies

PURPOSE

To determine the severity and nature of audiometric threshold shifts for patients with pulsatile tinnitus (PT) due to sigmoid sinus wall anomalies (SSWA).

MATERIALS AND METHODS

38 patients with SSWAs and available pre-operative audiograms were examined. Low- and high-frequency pure tone averages (LF-PTA, HF-PTA) were calculated. Audiometric data were compared between affected and unaffected ears, with the interaural difference (affected-unaffected PTA) representing the change in hearing due to PT. Additionally, post-operative change was examined in 14 patients with available data.

RESULTS

The average pre-operative air conduction (AC) LF-PTA was 17.04 dB on the affected side and 11.38 dB on the unaffected side (p < 0.001). The mean AC HF-PTA was significantly higher on the affected side as well (16.45 dB vs. 14.08 dB, p = 0.008). All shifts were sensorineural, with no significant air-bone gaps, and most subjects still had low-frequency thresholds in the normal range. Though the post-op change was not significant due to attrition, 5/14 patients (35.7%) had complete resolution of their pre-op interaural difference. A similar number developed a HF-PTA post-op threshold elevation in the surgical ear.

CONCLUSIONS

PT due to SSWAs causes a mean 6 dB low-frequency bone-conduction threshold elevation, and smaller high-frequency threshold shifts, due to masking. Patients with larger threshold shifts should have other potential causes of hearing loss explored.

LEVEL OF EVIDENCE

Level IV.

Longitudinal analysis of surgical outcome in subjects with pulsatile tinnitus originating from the sigmoid sinus

A dominant sigmoid sinus with either diverticulum or dehiscence (SS-Div/SS-Deh) is a common cause of pulsatile tinnitus (PT). For PT originating from SS-Div/SS-Deh, an etiology-specific and secure reconstruction using firm materials is vital for optimal outcomes. As a follow-up to our previous reports on transmastoid SS resurfacing or reshaping for SS-Div/SS-Deh, this study aimed to evaluate the long-term results of transmastoid resurfacing/reshaping. We retrospectively reviewed 20 PT patients who were diagnosed with SS-Div/SS-Deh, underwent transmastoid resurfacing/reshaping, and were followed up for more than 1 year postoperatively. For PT, immediate and long-term changes (> 1 year) in loudness and annoyance were analyzed using the visual analog scale (VAS). Additionally, pre and postoperative objective measurements of PT using transcanal sound recording and spectro-temporal analysis (TSR-STA), imaging results, and audiological findings were comprehensively analyzed. Significant improvements in PT were sustained or enhanced for > 1 year (median follow-up period: 37 months, range: 12–54 months). On TSR-STA, both peak and root mean square amplitudes decreased after surgery. Also, the average pure-tone threshold at 250 Hz improved after surgery. Thus, our long-term follow-up data confirmed that the surgical management of PT originating from SS-Div/SS-Deh is successful with regard to both objective and subjective measures.

Extraluminal Sigmoid Sinus Angioplasty: A Pertinent Reconstructive Surgical Method Targeting Dural Sinus Hemodynamics to Resolve Pulsatile Tinnitus

OBJECTIVES

1) To provide information on the treatment of pulsatile tinnitus (PT) with transtemporal extraluminal sigmoid sinus angioplasty (ESSA); and 2) to discuss the current clinical management of PT.

STUDY DESIGN

This was a retrospective study.

SETTINGS

Multi-institutional tertiary university medical centers.

PATIENTS

Fifty-four PT patients with transverse-sigmoid sinus enlargement and prominent transverse-sigmoid junction with or without sigmoid sinus wall anomalies or transverse sinus anomalies.

INTERVENTION

All patients underwent ESSA under local anesthesia.

MAIN OUTCOME MEASURES

Intraoperative discoveries and surgical resolution of PT, morphology, and computational fluid dynamics.

RESULTS

Fifty-three of the 54 (98%) patients experienced a significant reduction in, or complete resolution of, PT after ESSA. No major surgical complications occurred, except for one case where we observed a full collapse of the sinus wall. On average, this surgery reduced the cross-sectional area at the transverse-sigmoid junction by 61.5%. Our intraoperative discoveries suggest that sigmoid sinus wall anomalies may not be a definitive cause of PT. The transverse-sigmoid sinus system was significantly larger (in term of both cross-sectional area and volume) on the ipsilesional side compared with the contralesional side. Following ESSA, the vascular wall pressure and vortex flow at the transverse-sigmoid junction decreased considerably, and the flow velocity and wall shear stress increased significantly.

CONCLUSION

ESSA is a highly effective surgical technique for PT patients with transverse-sigmoid sinus enlargement and prominent transverse-sigmoid junction, regardless of whether they also have sigmoid sinus wall or transverse sinus anomalies. A large transverse-sigmoid system with prominent transverse-sigmoid junction is a predisposing factor for PT, and only by improving patients' intrasinus hemodynamics could PT be resolved efficiently. In cases without complete obstruction of venous return, ESSA is safe. No postoperative complications related to neurological disorders were observed.

Hemodynamic study on the different therapeutic effects of SSWD resurfacing surgery on patients with pulsatile tinnitus

Sigmoid sinus wall anomalies (SSWA) are a common pathophysiology of pulsatile tinnitus (PT) and usually treated by sigmoid sinus wall dehiscence (SSWD) resurfacing surgery. However, symptoms of tinnitus remain unrelieved after surgery in some patients with PT, and even new tinnitus appears. The cause of the difference in therapeutic effects is unclear. In this study, eight patient-specific SSWA geometric models were reconstructed on the basis of computed tomography angiography, including four cases of postoperative rehabilitation (group 1, 1-4 cases) and four cases of non-rehabilitation (group 2, 5-8 cases). Transient-state computational fluid dynamics (CFD) was performed to clarify the SS blood flow pattern and hemodynamic states. The wall pressure distribution on SSWA area, pressure difference, and flow pattern in SS were calculated to evaluate the hemodynamic changes of rehabilitation and non-rehabilitation patients before and after surgery. The difference of hemodynamics between these patients was statistically analyzed. The accuracy of CFD simulation was evaluated by cross validating the numerical and particle image velocimetry experimental results. Results showed that the SSWA area in patients with PT was loaded with high pressure. No difference was found in the hemodynamic characteristics between the two groups pre- and postoperation. When the average pressure (P_avg) and time-average P_avg (TAP_avg) on the SSWA area were studied, the TAP_avg difference pre- and postoperation between the two groups was found significant (p = 0.0021). The TAP_avg difference had a negative change in postoperative rehabilitation patients (case 1, -44.49 Pa vs. case 2, -15.85 Pa vs. case 3, -25.88 Pa vs. case 4, -16.58 Pa). The postoperative TAP_avg of non-rehabilitation patients was higher than the preoperative one (case 5, 24.70 Pa vs. case 6, 28.56 Pa vs. case 7, 5.81 Pa vs. case 8, 13.04 Pa). The velocity streamlines in the SS with rehabilitation became smoother and more regular than that without rehabilitation. By contrast, the velocity streamlines in SS without rehabilitation showed increased twisting and curling. No difference was found in time-average volume-averaged vorticity (TAV_avgV) between the two groups. Therefore, the high pressure of the vessel wall on SSWA area was one of the causes of PT. The variation of SSWA wall pressure difference before and after PT was the cause of the difference in therapeutic effects after SSWD resurfacing surgery. In patients with SSWA, disordered blood flow in SS was another cause of PT. SSWD repair may relieve tinnitus to some extent, but blood flow disorders may still arise.

Vestibulocochlear Symptoms Caused by Vertebrobasilar Dolichoectasia

OBJECTIVES

Vertebrobasilar dolichoectasia (VBD), an elongation and distension of vertebrobasilar artery, may present with cranial nerve symptoms due to nerve root compression. The objectives of this study are to summarize vestibulocochlear manifestations in subjects with VBD through a case series and to discuss the needs of thorough oto-neurotologic evaluation in VBD subjects before selecting treatment modalities.

METHODS

Four VBD subjects with vestibulocochlear manifestations were reviewed retrospectively. VBD was confirmed by either brain or internal auditory canal magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA). Patient information, medical history, MRI/MRA findings, and audiometry or vestibular function tests were reviewed according to patient's specific symptom.

RESULTS

Of the four subjects, three presented with ipsilesional sensorineural hearing loss (SNHL), three with paroxysmal recurrent vertigo, and two with typewriter tinnitus. The MRI/MRA of the four subjects revealed unilateral VBD with neurovascular compression of cisternal segment or the brainstem causing displacement, angulation, or deformity of the cranial nerve VII or VIII that corresponded to the symptoms.

CONCLUSION

Vestibulocochlear symptoms such as SNHL, recurrent paroxysmal vertigo, or typewriter tinnitus can be precipitated from a neurovascular compression of the vestibulocochlear nerve by VBD. Because proper medical or surgical treatments may stop the disease progression or improve audio-vestibular symptoms in subjects with VBD, a high index of suspicion and meticulous radiologic evaluation are needed when vestibulocochlear symptoms are not otherwise explainable, and if VBD is confirmed to cause audiovestibular manifestation, a thorough oto-neurotologic evaluation should be performed before initial treatment.

Treatment of pulsatile tinnitus caused by anomalies of the sigmoid sinus wall via combined internal and external sigmoid sinus wall reconstruction with 3D temporal bone CT guidance

PURPOSE

The present analysis aims to describe a surgical approach wherein pulsatile tinnitus (PT) arising due to sigmoid sinus wall anomalies (SSWA) can be treated via combination internal and external sigmoid sinus wall reconstruction. We further evaluated the utility of temporal bone 3D-CT imaging during both the pre- and post-operative assessments of all treated patients.

METHODS

Data pertaining to 11 patients that had undergone sigmoid sinus wall reconstruction were retrospectively analyzed. All of these patients underwent preoperative 3D-CT imaging assessment. These patients were additionally subjected to sigmoid sinus wall reconstruction via a combined internal and external layer approach. Postoperatively, all patients underwent a radiological assessment of auricular cartilage and autologous bone powered displacement. Patients were additionally asked about any subjective changes in PT or associated symptoms at follow-up time points.

RESULTS

SSWA in the 3D-CT imaging from these patients were all distinct. In 10/11 patients, PT fully resolved following reconstruction of the sinus wall. The remaining patients exhibited significant improvements in symptoms postoperatively, with PT fully resolving within a 1-month follow-up period. No patients suffered any major complications.

CONCLUSIONS

Temporal bone 3D-CT imaging allow for effective visualization of SSWA, enabling effective pre- and post-operative assessments of treated patients. A combined internal and external layer approach to sigmoid sinus wall reconstruction can be implemented safely and effectively, yielding high rates of satisfactory outcomes and achieving rigid reconstruction of this surface. As such, there is clear value in the consideration of this approach when treating individuals suffering from PT as a result of SSWA.

Sandwich technique for sigmoid sinus wall reconstruction for treatment of pulsatile tinnitus caused by sigmoid sinus diverticulum/dehiscence

Background: If the pulsatile tinnitus caused by sigmoid sinus diverticulum/dehiscence cannot be diagnosed and treated, it can lead to significant morbidity and mortality.Aim: To assess the sandwich surgical technique for sigmoid sinus wall reconstruction for the treatment of pulsatile tinnitus caused by sigmoid sinus diverticulum/dehiscence.Methods: A chart review was conducted with 17 patients suffering from pulsatile tinnitus caused by sigmoid sinus diverticulum/dehiscence who underwent sinus wall reconstruction surgery between January 2014 and July 2019.Results: Of the total patients studied, 16 were female, and one was male. The procedure was performed on the right ear of 15 patients and on the left ear of 2 patients. The pulsatile tinnitus disappeared in all patients following the sinus wall reconstruction surgery using the sandwich technique. The mean follow-up time was 25 months (a range of 8-55 months). In the follow-up period, no recurrence of pulsatile tinnitus was found. None of the patients experienced major complications such as thrombosis.Conclusions: The sandwich surgical technique for sinus wall reconstruction as a treatment for pulsatile tinnitus caused by sigmoid sinus diverticulum is safe and effective.

A study on relationship between pulsatile tinnitus and temporal bone pneumatization grade

Pulsatile tinnitus (PT) is a common symptom in otology. In some cases, the venous flow in the sigmoid sinus (SS) is the source of PT. It is suggested that the venous sound is propagated into the tympanic cavity through the air pathway of temporal bone air cells (TBAC). The hyperpneumatization of TBAC was hypothesized as a direct pathology of PT through amplifying the venous sound, but there is no quantitative analysis. This study aims to quantify the relationship between the venous sound amplification and the pneumatization grade of TBAC. The acoustic numerical simulation and statistical analysis were performed based on the radiology data of 21 pulsatile tinnitus patients. The TBAC of these patients were classified into hypopneumatization, normal pneumatization and hyperpneumatization grades according to three standards. The in vitro acoustic experiment was done as the validation of simulation. It is indicated that the SS standard is effective for the clinical evaluation of venous sound amplification. The TBAC amplifies the venous sound due to the acoustic resonance at the first mode frequency, regardless of the pneumatization grades. The normal pneumatic TBAC exhibits the highest sound amplification effect on the venous sound amongst the three grades, contributing mostly to PT, but would not induce PT without any other causes.

Systematic Review of Temporal Bone-Resurfacing Techniques for Pulsatile Tinnitus Associated with Vascular Wall Anomalies

OBJECTIVE

To systematically review literature evidence on temporal bone-resurfacing techniques for pulsatile tinnitus (PT) associated with vascular wall anomalies.

DATA SOURCES

We searched PubMed, Embase, and the Cochrane Database. The period covered was from 1962 to 2018.

REVIEW METHODS

We included studies in all languages that reported resurfacing outcomes for patients with PT and radiographic evidence or direct visualization of sigmoid sinus wall anomaly, jugular bulb wall anomaly, or dehiscent or aberrant internal carotid artery.

RESULTS

Of 954 citations retrieved in database searches and 5 citations retrieved from reference lists, 20 studies with a total of 141 resurfacing cases involving 138 patients were included. Resurfacing outcomes for arterial sources of PT showed 3 of 5 cases (60%) with complete resolution and 2 (40%) with partial resolution. Jugular bulb sources of PT showed 11 of 14 cases (79%) with complete resolution and 1 (7%) with partial resolution. Sigmoid sinus sources of PT showed 91 of 121 cases (75%) with complete resolution and 12 (10%) with partial resolution. Symptoms occurred more in females and on the right side. Most cases (94%) used hard-density materials for resurfacing. Material density did not appear to be associated with resurfacing outcomes. Use of autologous materials was associated with improved outcomes for arterial sources resurfacing. Major complications involving sigmoid sinus thrombosis or compression were reported in 4% of cases without long-term morbidity or mortality.

CONCLUSIONS

Resurfacing surgery is likely effective and well tolerated for select patients with PT associated with various vascular wall anomalies.

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.

Arteriovenous malformation of the external ear: a clinical assessment with a scoping review of the literature

Introduction

Auricular Arteriovenous Malformation of the external ear is a rarely encountered disease; in particular, arteriovenous malformation arising from the auricle, with spontaneous bleeding, has seldom been reported.

Objective

In the current study, we report an unusual case of late-onset auricular arteriovenous malformation originating from the posterior auricular artery that was confirmed by computed tomographic angiography. The case was successfully managed by pre-surgical intravascular embolization followed by total lesion excision. Prompted by this case, we also present a scoping review of the literature.

Methods

A case of a 60 year-old man with right auricular arteriovenous malformation treated in our tertiary care center, and 52 patients with auricular arteriovenous malformation described in 10 case reports and a retrospective review are presented. Auricular arteriovenous malformation can manifest as swelling of the ear, pulsatile tinnitus, pain, and/or bleeding. On physical examination, a pulsatile swelling and/or a tender mass is evident. When arteriovenous malformation is suspected, the lesions should be visualized using imaging modalities that optimally detect vascular lesions, and managed via embolization, mass excision, or auricular resection. Effectiveness of the various diagnostic methods used and the treatment outcomes were analyzed.

Results

Various imaging modalities including Doppler sonography, computed tomographic angiography, magnetic resonance angiography, and/or transfemoral cerebral angiography were used to diagnose 38 cases reported in the literature. In another 15 cases, no imaging was performed; treatment was determined solely by physical examination and auscultation. Of the total of 53 cases, 12 were not treated (their symptoms were merely observed) whereas 20 underwent therapeutic embolization. In total, 32 patients, including 1 patient who was not treated and 10 with persistent or aggravated arteriovenous malformation after previous embolization, underwent mass excision or auricular resection depending on the extent of the lesion. No major postoperative complication was recorded. The postoperative follow-up duration varied from 1 month to 19 years, and only one case of unresectable, residual cervicofacial arteriovenous malformation was recorded.

Conclusion

Auricular arteriovenous malformation is a rarely encountered disease, but should be suspected if a patient presents with a swollen ear and pulsatile tinnitus. Appropriate imaging is essential for diagnosis and evaluation of the extent of disease. As embolization affords only relatively poor control, total surgical removal of the vascular mass is recommended.

Dural arteriovenous fistula masquerading as pulsatile tinnitus: radiologic assessment and clinical implications

Pulsatile tinnitus (PT) is often an initial presenting symptom of dural arteriovenous fistula (dAVF), but it may be overlooked or diagnosed late if not suspected on initial diagnostic work-up. Here, we assess anatomical features, treatment outcomes, and clinical implications of patients with PT due to dAVF. Of 220 patients who were diagnosed with dAVF between 2003 and 2014, 30 (13.6%) presented with only PT as their initial symptom. The transverse-sigmoid sinus (70.0%) was the most common site, followed by the hypoglossal canal (10.0%) and the middle cranial fossa (6.7%) on radiologic evaluation. Regarding venous drainage patterns, sinus or meningeal venous drainage pattern was the most common type (73.3%), followed by sinus drainage with a cortical venous reflux (26.7%). PT disappeared completely in 21 (80.8%) of 26 patients who underwent therapeutic intervention with transarterial embolization of the fistula, improved markedly in 3 (11.5%), and remained the same in 2 (7.7%). In conclusion, considering that PT may be the only initial symptom in more than 10% of dAVF, not only otolaryngologists but also neurologists and neurosurgeons should meticulously evaluate patients with PT. In most cases, PT originating from dAVF can be cured with transarterial embolization regardless of location and venous drainage pattern.

Sigmoid Sinus Wall Reconstruction for Pulsatile Tinnitus Caused by Sigmoid Sinus Wall Dehiscence: A Single-Center Experience

OBJECTIVE

To evaluate clinical characteristics and present surgical outcomes of PT caused by sigmoid sinus wall dehiscence (SSWD).

METHODS

This study retrospectively reviewed 34 patients with PT who were diagnosed with SSWD in our institution between December 2008 and July 2013. Among them, 27 patients underwent sigmoid sinus wall reconstruction (surgery group) and 7 patients refused surgery (non-surgery group). Preoperative data were obtained from the patients' medical records. All patients were followed up regularly for at least 25 months. Preoperative and postoperative computed tomography angiography (CTA) images were compared. Student's t-tests were used to compare age, body mass index (BMI) and preoperative Tinnitus Handicap Inventory (THI) scores between the surgery and the non-surgery groups and to compare pre- and follow-up THI scores.

RESULTS

There was no significant difference in age, body mass index, or preoperative THI scores between groups. Following surgery, 14 patients had complete resolution, 5 had partial resolution, 7 experienced no change and PT was aggravated in 1 patient. The difference between preoperative and postoperative THI scores was significant. No severe complications were found postoperatively. Comparison of the preoperative and postoperative CTA images revealed that remnant unrepaired dehiscences were the cause of unsatisfactory outcomes following surgery. In the non-surgery group, PT remained largely unchanged.

CONCLUSIONS

Sigmoid sinus wall reconstruction is an effective and safe treatment for PT caused by SSWD. It is imperative that all regions of the dehiscence are sufficiently exposed and resurfaced during surgery.

Pre-Treatment Objective Diagnosis and Post-Treatment Outcome Evaluation in Patients with Vascular Pulsatile Tinnitus Using Transcanal Recording and Spectro-Temporal Analysis

OBJECTIVE

Although vascular pulsatile tinnitus (VPT) has been classified as "objective", VPT is not easily recognizable or documentable in most cases. In response to this, we have developed transcanal sound recording (TSR) and spectro-temporal analysis (STA) for the objective diagnosis of VPT. By refining our initial method, we were able to apply TSR/STA to post-treatment outcome evaluation, as well as pre-treatment objective diagnosis.

METHODS

TSR was performed on seven VPT patients and five normal controls before and after surgical or interventional treatment. VPT was recorded using an inserted microphone with the subjects placed in both upright and supine positions with 1) a neutral head position, 2) head rotated to the tinnitus side, 3) head rotated to the non-tinnitus side, and 4) a neutral position with ipsi-lesional manual cervical compression. The recorded signals were analyzed in both time and time-frequency domains by performing a short-time Fourier transformation.

RESULTS

The pre-treatment ear canal signals of all VPT patients demonstrated pulse-synchronous periodic structures and acoustic characteristics that were representative of their presumptive vascular pathologies, whereas those the controls exhibited smaller peaks and weak periodicities. Compared with the pre-treatment signals, the post-treatment signals exhibited significantly reduced peak- and root mean square amplitudes upon time domain analysis. Additionally, further sub-band analysis confirmed that the pulse-synchronous signal of all subjects was not identifiable after treatment and, in particular, that the signal decrement was statistically significant at low frequencies. Moreover, the post-treatment signals of the VPT subjects revealed no significant differences when compared to those of the control group.

CONCLUSION

We reconfirmed that the TSR/STA method is an effective modality to objectify VPT. In addition, the potential role of the TSR/STA method in the objective evaluation of treatment outcomes in patients with VPT was proven. Further studies incorporating a larger sample size and more refined recording techniques are warranted.