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1.
Laryngoscope ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804647

RESUMO

OBJECTIVE: Sigmoid sinus wall anomalies (SSWA) are closely linked to venous pulsatile tinnitus (PT). This study aims to demonstrate that SSWA develops progressively rather than being congenital. METHODS: We retrospectively analyzed 42 PT patients with SSWA who had at least two non-operative CT scans at our clinic. CT images were longitudinally assessed to track SSWA progression, while MRI and Doppler ultrasound evaluated transverse sinus stenosis and venous hemodynamics. Changes in PT perception were tracked using the tinnitus handicap inventory (THI) questionnaire. RESULTS: Among the 42 SSWA patients, 12 (28.6%) exhibited progression. Anastomosis between diploic vein and diverticulum was significantly higher compared to the dehiscence cohort (p < 0.01). Within the diverticulum group, seven individuals (30.4%) experienced enlargement, with a mean diverticular wall expansion of 5.9% ± 11.4%. Progressive erosion was observed in two cases (12.5%) in the dehiscence cohort, with a mean sigmoid plate erosion of 3.8% ± 10.1%. In cases progressing from dehiscence to diverticulum, three subjects transitioned, with a mean sigmoid sinus wall length expansion of 43.8% ± 31.9%. SSWA progression showed a significant negative correlation with QBILATERAL (r = -0.857, p = 0.014), and there was a significant difference between initial and revisit THI scores (p < 0.01). CONCLUSION: SSWA can undergo morphological progression, indicating it is a progressive clinical condition rather than congenital. LEVEL OF EVIDENCE: 4 Laryngoscope, 2024.

2.
Otol Neurotol ; 45(2): 154-162, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38152047

RESUMO

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.


Assuntos
Divertículo , Procedimentos de Cirurgia Plástica , Zumbido , Humanos , Zumbido/cirurgia , Zumbido/complicações , Estudos Retrospectivos , Monitorização Intraoperatória , Cavidades Cranianas/cirurgia , Divertículo/complicações , Divertículo/diagnóstico por imagem , Divertículo/cirurgia
3.
Front Surg ; 10: 1268829, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37841818

RESUMO

Transverse sinus (TS) stenosis is common in individuals with venous pulsatile tinnitus (PT). While PT can be addressed by endoluminal or extraluminal methods, the former has shown promise in alleviating symptoms associated with increased intracranial pressure. This study explores the potential of extraluminal methods to alleviate TS stenosis and eliminate PT caused by sigmoid sinus diverticulum. A 31-year-old male patient presenting with left-sided PT, attributed to a large, pedunculated sigmoid sinus diverticulum along with severe ipsilateral TS stenosis and contralateral TS hypoplasia, underwent ipsilateral extraluminal TS decompression surgery following sigmoid sinus wall reconstruction under local anesthesia. Postoperative CT and MR angiography revealed a significant increase in the TS lumen from 0.269 to 0.42 cm2 (56.02%) 2 years after surgery. Cervical Doppler ultrasound demonstrated a 36.07% increase in ipsilateral outflow volume to 16.6 g/s and a 77.63% increase in contralateral outflow volume to 1.35 g/s. In conclusion, this pioneering study showcases the potential of transtemporal TS decompression surgery in creating space for adaptive expansion of the TS lumen. However, the procedure should be reserved for individuals with severely compromised venous return.

4.
J Int Med Res ; 51(8): 3000605231187949, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37548322

RESUMO

OBJECTIVE: This study was performed to investigate the dynamics of intracranial pressure (ICP) alterations and bilateral transverse-sigmoid sinus morphologies in patients with venous pulsatile tinnitus (PT). METHODS: This retrospective study involved 27 patients with venous PT associated with sigmoid sinus wall anomalies. ICP and ICP metrics were measured by cerebrospinal fluid manometry and internal jugular vein compression tests. Correlation analysis was performed to determine the statistical correlation between ICP and the morphological metrics. RESULTS: The mean ICP was 212.5 ± 47.3 mmH2O. The median ΔICPtotal was 130 (range, 55-150) mmH2O. The ΔICPtotal was linearly correlated with the open lumbar pressure, and a significant difference was found between patients with normal and elevated cerebrospinal fluid pressure. The ΔICPdifference was linearly correlated with the Lendifference and Voldifference. ΔICP was linearly correlated with Lendifference. CONCLUSIONS: Complete obstruction of flow patency should be avoided in patients with low ICP and large volumetric/patency differences in the bilateral transverse-sigmoid sinus systems.


Assuntos
Zumbido , Seios Transversos , Humanos , Estudos Retrospectivos , Seios Transversos/anormalidades , Cavidades Cranianas , Pressão do Líquido Cefalorraquidiano
5.
Front Neurol ; 14: 1293899, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38274869

RESUMO

This case report discusses a unique instance of pulsatile tinnitus (PT) caused by a rare type of intracranial dural arteriovenous fistula (DAVF) located in the sphenoid wing (SW) region, with PT being the sole presenting symptom. The patient initially received multiple misdiagnoses and sought medical attention at various hospitals before being correctly diagnosed. Imaging studies revealed the DAVF's presence in the SW region, which led to the patient's referral to interventional radiology/neurology, although she chose conservative observation without surgical intervention. Remarkably, the patient's PT spontaneously ceased after 30 months without any apparent cause, and follow-up imaging confirmed the absence of DAVF-related abnormalities. The case highlights the importance of considering DAVF as a potential cause of PT, even when there are no evident abnormalities in proximity to the auditory apparatus. It also emphasizes the need for otolaryngologists to extend their examination to include regions beyond the temporal bone, such as the sphenoid bone and orbital areas, when PT is the exclusive symptom. The case underscores the significance of early detection and intervention for DAVFs, as they can lead to debilitating complications, despite the rare occurrence of spontaneous symptom resolution in this case.

6.
Front Bioeng Biotechnol ; 10: 948230, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36420442

RESUMO

Investigations of pulsatile tinnitus (PT) caused by sigmoid sinus wall anomalies (SSWAs) using computational fluid dynamics (CFD) have recently increased in prevalence. However, accurate modeling of anatomical structures regarding sigmoid plate dehiscence and acoustic sources of PT remains lacking. This study incorporates coupled CFD techniques, micro-computed tomography, and scanning electron microscope to reveal the vibroacoustic and hydroacoustic sources and displacement characteristics of the transverse-sigmoid sinus system. Furthermore, the in vivo transcanal-recording technique combined with ipsilateral internal jugular vein compression was implemented to cross-reference the captured acoustic profile of PT with the calculated results. In this study, the transient state coupled CFD technique was used to calculate the vibroacoustic and hydroacoustic sources. The dehiscent sigmoid plate and periosteal dura mater were then reconstructed. The displacement characteristics and acoustic results were analyzed. The displacement of the vascular wall underneath the dehiscent area was 9.6 times larger than that of the sigmoid plate and 3,617 times smaller than that of the vascular wall without the overlying osseous structures. The peak amplitude of flow-induced vibroacoustic noise was 119.3 dB at 20.2 Hz measured at the transverse sinus. Within the observed 20-1,000 Hz frequency range, the largest peak amplitude of hydroacoustic noise was 80.0 dB at 20.2 Hz located at the jugular bulb region. The simulated results conformed with the in vivo acoustic profile which the major frequency of PT falls within 1,000 Hz. In conclusion, 1) the sigmoid plate and dura mater greatly impact vascular wall displacement, which should not be overlooked in CFD simulations. 2) By incorporating the transcanal recording technique with IJV compression test, the primary frequency of PT was found fluctuating below 1,000 Hz, which matches the frequency component simulated by the current CFD technique; amplitude-wise, however, the peak amplitude of in vivo pulse-synchronous somatosound measures approximately 10 dB, which is comparatively lesser than the CFD results and the subjectively perceived loudness of PT. Thus, the transmission pathway, intramastoid acoustic impedance/amplification effect, and the perceptive threshold of PT require further investigations to minimize the incidence of surgical failure.

7.
Front Neurol ; 13: 992416, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36188386

RESUMO

The clinical and hemodynamic characteristics of venous pulsatile tinnitus (PT) patients with normal or elevated cerebrospinal fluid pressure (CSFP) have not been clearly differentiated. This study aimed to explore CSFP among patients with PT as the solitary symptom, as well as quantitatively and qualitatively assess the role of the degree of transverse sinus (TS) stenosis and jugular hemodynamics in venous PT patients. A total of 50 subjects with venous PT with or without sigmoid sinus wall anomalies (SSWAs) were enrolled in this study. In addition to radiologic assessments for TS stenosis and invagination of arachnoid granulation (AG) in TS, CSFP and jugular hemodynamics were measured via cerebrospinal fluid (CSF) manometry and Doppler ultrasound. Apart from group comparisons and correlation analyses, multivariate linear regression, and receiver operating characteristic (ROC) models were used to identify the sensitivity and specificity of the index of transverse sinus stenosis (ITSS) and hemodynamic variables with inferential significance. The mean CSFP of all cases was 199.5 ± 52.7 mmH2O, with no statistical difference in CSFP between the diverticulum and dehiscence groups. Multivariate linear regression analysis demonstrated that CSFP was linearly correlated with ITSS and pulsatility index (PI). ROC analysis showed that the area under the ROC curve of PI was 0.693 at 200 mmH2O threshold, and the best PI cut-off value was 0.467, with a sensitivity of 65.7% and specificity of 81.8%. For 250 mmH2O threshold, the area under the ROC curve of PI was 0.718, and the best PI cut-off value was 0.467 with a sensitivity of 68.4% and specificity of 75.0%. Additionally, the area under the ROC curve of ITSS was 0.757, and the best ITSS cutoff value was 8.5 (p = 0.002, 95% CI = 0.616-0.898) with a sensitivity of 72.4% and specificity of 75.0% at 200 mmH2O threshold. In conclusion, patients with venous PT as the only presenting symptom should be suspected of having borderline or increased CSFP when they present with high ITSS, BMI and low PI. Further, AG in TS without encephalocele and empty sellae are not limiting findings for differentiating the level of CSFP in patients with venous PT.

8.
Front Hum Neurosci ; 16: 862420, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35782046

RESUMO

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.

9.
ORL J Otorhinolaryngol Relat Spec ; 84(3): 219-228, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34311465

RESUMO

OBJECTIVE: Venous pulsatile tinnitus (PT) has received increasing attention recently. As analyses of psychophysical and neuropsychological dimensions of venous PT are lacking, this study aimed to quantitatively and qualitatively investigate the correlation among audiometric, hydroacoustic, and subjective outcomes in patients with PT. METHODS: Fifty-five venous PT patients, with or without sigmoid sinus wall anomalies (SSWAs), were subdivided into SSWAs (n = 30) and non-SSWAs (n = 25) groups. Audiometric and hemodynamic evaluations were assessed. Questionnaires including the Tinnitus Handicap Inventory, Hospital Anxiety and Depression Scale (HADS), and Athens Insomnia Scale (AIS) were deployed to evaluate the psychological impacts of PT. RESULTS: Among 55 subjects, PT frequency-related pure-tone audiometry (PTA) was significantly different between ipsilesional non-PT frequency-related PTA (p < 0.01), ipsilateral jugular vein compression PTA (p < 0.01), and contralesional ear PTA (p < 0.01). In contrast with the pulsatility index and flow velocity, bilateral EOET and flow volume were significantly different (p < 0.01). Of the 3 questionnaire types, there was a strong correlation between HADS anxiety and AIS scores (r = 0.658, p < 0.01). The duration of PT was not correlated with subjective outcomes, and there was no statistical significance found among audiometric, hemodynamic, and subjective outcomes between SSWAs and non-SSWAs groups. CONCLUSIONS: (1) The duration of PT was irrelevant to the increase of PTA. (2) Venous PT is the perception of vascular flow sound, in which hydroacoustic characteristics can be highly independent. (3) Anxiety, depression, and sleep disorders commonly prevail among PT patients.


Assuntos
Seios Paranasais , Zumbido , Audiometria de Tons Puros , Cavidades Cranianas/anormalidades , Cavidades Cranianas/diagnóstico por imagem , Humanos , Zumbido/diagnóstico por imagem , Ultrassonografia Doppler
10.
Front Surg ; 9: 1014649, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36684374

RESUMO

Pulsatile tinnitus (PT) caused by enlarged oblique occipital sinus (OOS) and resultant diverticulum/dehiscence of the sigmoid-jugular wall has not been described in previous literature. This study recruits one case of PT induced by ipsilateral enlarged OOS and sigmoid-jugular wall diverticulum (case 1) alongside one case of PT induced by ipsilateral enlarged OOS and sigmoid-jugular wall dehiscence (case 2). Various radiologic and computational techniques including computed tomography (CT), magnetic resonance (MR) imaging, Doppler ultrasound, and computational fluid dynamics (CFD) simulation were implemented. Transmastoid sinus wall reconstruction was performed on case 1 with a large sigmoid-jugular diverticulum potentially traumatizing the facial nerve canal. Contrast-enhanced CT or MR venogram images coupling with three-dimensional reconstructed are advantageous in revealing the covert route of OOS that runs under the cerebellum and drains directly into jugular bulb (JB) region. PT in case 1 was successfully eliminated after transmastoid sinus wall reconstruction surgery. Tinnitus handicap inventory score in case 1 reduced from 70 to 0. The ipsilateral jugular outflow mean velocity (Vmn) and flow volume (FVOL) were 42.5 cm/s and 25.9 g/s (case 1 prior to surgery) and 56.6 cm/s and 41.2 g/s (case 2), respectively. Based on CFD simulation, the peak flow velocity in OOS was 1.85 m/s and 2.1 m/s, the wall pressure of the diverticular dome and dehiscence area of the SS-JB wall was 1724.7 Pa and 369.8 Pa in case 1 and 2, respectively. Enlarged OOS caries greater flow kinetic energy that possibly induces sigmoid-jugular wall diverticulum/dehiscence; transmastoid surgical method is safe and therapeutically effective against PT induced by enlarged OOS.

11.
Laryngoscope Investig Otolaryngol ; 6(6): 1436-1448, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34938885

RESUMO

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.

12.
Arch Biochem Biophys ; 701: 108752, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33675811

RESUMO

Hearing loss caused by ototoxic drugs is a kind of acquired hearing loss. Cisplatin is one of the most commonly used drugs and its main action sites are hair cells (HCs). Sorcin is a drug-resistant calcium-binding protein belonging to the small penta-EF-hand protein family. Sorcin is highly expressed in many tissues, including bone, heart, brain, lung, and skin tissues. Single-cell RNA sequencing showed that sorcin was expressed in the outer HCs of mice, but its role remained unknown. We also found that sorcin was highly expressed in the cytoplasm of cochlear HCs and HEI-OC1 cells. After cisplatin injury, the expression of sorcin in HCs and HEI-OC1 cells decreased significantly. SiRNA transfection technology was used to knock down the expression of sorcin. The results showed that the number of apoptotic cells, the expression of cleaved caspased-3, and the expression of Bax increased while the anti-apoptotic factor Bcl-2 decreased in the siRNA-Sorcin + CIS group. The observed increase in apoptosis was related to the increase of reactive oxygen species (ROS) and the destruction of the mitochondrial membrane potential (MMP). Finally, we found that the downregulated sorcin worked by activating the P-ERK1/2 signaling pathway. Overall, this study showed that sorcin can be used as a new target to prevent the ototoxicity of platinum drugs.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas de Ligação ao Cálcio/biossíntese , Cisplatino/efeitos adversos , Células Ciliadas Auditivas/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Ototoxicidade/metabolismo , Animais , Apoptose/genética , Proteínas de Ligação ao Cálcio/genética , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular , Cisplatino/farmacologia , Técnicas de Silenciamento de Genes , Células Ciliadas Auditivas/patologia , Sistema de Sinalização das MAP Quinases/genética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/genética , Camundongos , Ototoxicidade/genética , Ototoxicidade/patologia , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
13.
Auris Nasus Larynx ; 48(5): 852-863, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33468352

RESUMO

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.


Assuntos
Cavidades Cranianas/cirurgia , Zumbido/cirurgia , Acústica , Simulação por Computador , Cavidades Cranianas/anormalidades , Cavidades Cranianas/diagnóstico por imagem , Feminino , Humanos , Hidrodinâmica , Modelos Lineares , Masculino , Procedimentos Cirúrgicos Otológicos , Zumbido/fisiopatologia , Seios Transversos/anormalidades , Seios Transversos/diagnóstico por imagem , Seios Transversos/cirurgia , Ultrassonografia Doppler em Cores
14.
Front Bioeng Biotechnol ; 9: 777648, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35047487

RESUMO

The application of grafts and biomaterials is a cardinal therapeutic procedure to resolve venous pulsatile tinnitus (PT) caused by temporal bone dehiscence during transtemporal reconstructive surgery. However, the transmission mechanism of venous PT remains unclear, and the sound absorption and insulation properties of different repair materials have not been specified. This study quantifies the vibroacoustic characteristics of PT, sources the major transmission pathway of PT, and verifies the therapeutic effect of different material applications using joint multi-sensing platforms and coupled computational fluid dynamics (CFD) techniques. The in vivo intraoperative acoustic and vibroacoustic characteristics of intrasinus blood flow motion and dehiscent sigmoid plate of a typical venous PT patient were investigated using acoustic and displacement sensors. The acoustical, morphological, and mechanical properties of the dehiscent sigmoid plate, grafts harvested from a cadaveric head, and other biomaterials were acquired using acoustical impedance tubes, micro-CT, scanning electron microscopy, and mercury porosimetry, as appropriate. To analyze the therapeutic effect of our previous reconstructive techniques, coupled CFD simulations were performed using the acquired mechanical properties of biomaterials and patient-specific radiologic data. The peak in vivo intraoperatively gauged, peak simulated vibroacoustic and peak simulated hydroacoustic amplitude of PT prior to sigmoid plate reconstruction were 64.0, 70.4, and 72.8 dB, respectively. After the solidified gelatin sponge-bone wax repair technique, the intraoperative gauged peak amplitude of PT was reduced from 64.0 to 47.3 dB. Among three different reconstructive techniques based on CFD results, the vibroacoustic and hydroacoustic sounds were reduced to 65.9 and 68.6 dB (temporalis-cartilage technique), 63.5 and 63.1 dB (solidified gelatin sponge technique), and 42.4 and 39.2 dB (solidified gelatin sponge-bone wax technique). In conclusion, the current novel biosensing applications and coupled CFD techniques indicate that the sensation of PT correlates with the motion and impact from venous flow, causing vibroacoustic and hydroacoustic sources that transmit via the air-conduction transmission pathway. The transtemporal reconstructive surgical efficacy depends on the established areal density of applied grafts and/or biomaterials, in which the total transmission loss of PT should surpass the amplitude of the measured loudness of PT.

15.
Auris Nasus Larynx ; 48(6): 1181-1188, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32682595

RESUMO

OBJECTIVE: Pulsatile tinnitus (PT) caused by an aberrant artery is rare. We report an unprecedented cause of PT resulting from an aberrant artery coursing the mastoid surface, and qualitatively discuss the pathophysiology of PT. METHODS: This case study reports a 41-year-old woman who presented with persistent PT at her right retromastoid region. Contrast-enhanced computed tomography revealed an aberrant branch of the artery that coursed over the cortex of the mastoid bone. Surgical ligation of this aberrant artery was performed under local anesthesia. RESULTS: Intraoperative findings suggested that PT transmitted via bone-conduction route due to the direct contact of the vascular and mastoid surface. PT was completely resolved upon surgical removal of this causative segment. Ultrasonographic and hemodynamic analysis showed that the turbulent kinetic energy and high regional wall pressure were the major contributory factors causing PT. Spectro-temporal analysis showed that PT fluctuates at frequency 500~2000 Hz, which differs from those of venous PT. CONCLUSION: Judicious preoperative and intraoperative assessments of PT ensure the surgical efficacy of PT. Objective ultrasonographic and computational studies can provide detailed hydroacoustic characteristics of PT.


Assuntos
Artérias/anormalidades , Processo Mastoide , Zumbido/etiologia , Malformações Vasculares/complicações , Acústica , Adulto , Artérias/diagnóstico por imagem , Artérias/cirurgia , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Processo Mastoide/diagnóstico por imagem , Espectrografia do Som , Ultrassonografia Doppler em Cores , Malformações Vasculares/diagnóstico por imagem , Malformações Vasculares/fisiopatologia
16.
Otol Neurotol ; 41(1): e132-e145, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31568136

RESUMO

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.


Assuntos
Angioplastia/métodos , Cavidades Cranianas/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Zumbido/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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