Endovascular coiling of large mastoid emissary vein causing pulsatile tinnitus

Imaging of Pulsatile Tinnitus

Tinnitus is a common complaint that approximately three-fourths of adults will experience at some point in their life. While for many it is a mild nuisance, for some it can be debilitating, affecting cognition and quality of life, increasing stress, and leading to anxiety, depression, and in severe circumstances even suicide. Pulsatile tinnitus refers to the perception of a heartbeat-like sound without external stimulus. Although less common than nonpulsatile tinnitus, pulsatile tinnitus raises concern for underlying disease that can have a high risk of causing the patient harm if undiagnosed, and most of these patients will have positive findings at imaging. While these findings are often subtle, identifying them can have a meaningful impact on the patient's quality of life. The literature on pulsatile tinnitus is changing rapidly with improved imaging techniques and novel minimally invasive treatment options. A careful history and physical examination together with appropriate imaging are therefore critical in identifying the underlying cause. With emerging surgical, endovascular, and supportive technologies, the vast majority of patients with bothersome pulsatile tinnitus can be cured or have their symptoms ameliorated. The objective of this narrative review is to present a comprehensive analysis of the currently available literature on pulsatile tinnitus, with a focus on understanding its pathophysiologic mechanisms, diagnostic pathways, imaging findings, and the spectrum of available management strategies and ultimately to propose a structured framework that aids radiologists as well as clinicians in identifying an underlying diagnosis and guiding management of these patients. ©RSNA, 2024 Supplemental material is available for this article.

Causes of Pulsatile Tinnitus and Treatment Options

Pulsatile tinnitus (PT) requires detailed workup to evaluate for an underlying structural cause. With advances in neuroimaging, structural venous abnormalities that can cause PT have becoming increasingly recognized. A number of anomalies, including dural arteriovenous fistulas, idiopathic intracranial hypertension, transverse sinus stenosis, sigmoid sinus wall abnormalities, jugular venous anomalies, and hypertrophied emissary veins, have been implicated in flow disruption and turbulence in the vicinity of auditory structures, resulting in PT. Endovascular treatment options, including stenting, coiling, and embolization with liquid agents, have demonstrated high efficacy and safety. These treatments can lead to symptomatic relief in carefully selected cases.

Endovascular vs surgical treatment of sigmoid sinus diverticulum causing pulsatile tinnitus: A systematic review

INTRODUCTION

Sigmoid sinus diverticulum (SSD) has been increasingly reported as a cause of pulsatile tinnitus (PT). While both endovascular and surgical treatments have been used, there is a lack of consensus on the treatment modality to treat SSD. We conducted a systematic review of the available literature to compare the clinical outcomes and safety of endovascular versus surgical approaches for treating SSD.

METHODS

A systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses to identify studies encompassing the management of SSD. Studies reporting the clinical outcomes and safety of endovascular or surgical treatments for SSD between January 2000 and January 2023 were included. Results were characterized using descriptive statistics.

RESULTS

Endovascular treatment (EVT) was reported by 17 articles, yielding 26 patients with 27 diverticula. Surgical treatment was reported by 20 articles, yielding 105 patients with 107 diverticula. EVT led to complete or near-complete resolution in all patients with SSD and PT. Complications occurred in 3.7% (1/27) with a return to baseline after 2 months. There were no permanent complications from EVT. Surgical treatment resulted in complete resolution in 77.6% (83/107) of cases, incomplete resolution in 11.2% (12/107), and no resolution in 11.2% (12/107). Significant complications occurred in 9.3% (10/107) of the surgical-treated patients.

CONCLUSION

EVT in patients with PT and venous diverticulum appears more effective and safer than surgical treatment, but large studies are lacking. Studies directly comparing endovascular and surgical treatment are needed.

Cerebral venous disorders: Diagnosis and endovascular management

The role of the venous circulation in neurological diseases has been underestimated. In this review, we present an overview of the intracranial venous anatomy, venous disorders of the central nervous system, and options for endovascular management. We discuss the role the venous circulation plays in various neurological diseases including cerebrospinal fluid (CSF) disorders (intracranial hypertension and intracranial hypotension), arteriovenous diseases, and pulsatile tinnitus. We also shed light on emergent cerebral venous interventions including transvenous brain-computer interface implantation, transvenous treatment of communicating hydrocephalus, and the endovascular treatment of CSF-venous disorders.

Intracranial Dural Arteriovenous Fistulas

Dural arteriovenous fistulas (DAVFs) are abnormal communications between meningeal arteries and dural venous sinuses and/or cortical veins. Although many fistulas are benign and do not require treatment, some may carry a significant risk of bleeding or cause symptoms and warrant treatment. This review provides a review of various aspects of intracranial DAVFs including epidemiology, pathophysiology, clinical presentation, imaging characteristics, classification, natural history, and management options. By exploring these topics, we aim to enhance understanding of this condition and facilitate patient care.

Characteristics and Management of Dilated Mastoid Emissary Veins: A Case Report and Literature Review

INTRODUCTION

The mastoid emissary vein (MEV) describes a transosseous connection between the sigmoid dural venous sinus and the suboccipital venous plexus. In cases of outflow stenosis or malformation, the MEV may become dilated and a source of pulsatile tinnitus (PT) amenable to treatment. We describe a case of PT secondary to MEV treated successfully via endovascular coil embolization and conduct a systematic review of the literature.

METHODS

We performed a systematic review without meta-analysis of studies involving management of dilated MEV on January 14, 2022, and describe a case of PT secondary to an enlarged MEV treated via coil embolization.

RESULTS

A total of 13 studies were selected for full review. Reports identified MEV presenting as PT in 60% (12 of 20) of cases, intraoperative hemorrhage in mastoid surgery in 15% (3 of 20), a compressive scalp mass in 10% (2 of 20), and thrombophlebitis, facial swelling, or an incidental finding in 5% (1 of 20) each. Forty-five percent (9 of 20) underwent treatment, with all experiencing symptom resolution or improvement. Surgery included transvenous coil embolization in 33.3% (3 of 9), flap reconstruction in 22.2% (2 of 9), and surgical packing, ligation, and thrombectomy in 11.1% (1 of 9) each. Dilated MEV was reported concurrently with impeded drainage pathways in 35% (7 of 20) of reports.

CONCLUSIONS

Dilated MEV has been reported as an etiology of pulsatile tinnitus and appears amenable to treatment via open and endovascular means. Endovascular coil embolization appears to offer effective symptom resolution, however, available literature exists only in case reports and small series. Further investigation is highly warranted.

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.

Bilateral Pulsatile Tinnitus Caused by Bilateral Dilated Mastoid Emissary Vein

Pulsatile tinnitus is a rhythmic type of tinnitus. Most cases are caused by vascular disorders and present as synchronous with the patient's heartbeat. A dilated mastoid emissary vein may cause pulsatile tinnitus. Here, we report the first case of bilateral pulsatile tinnitus caused by dilated bilateral mastoid emissary vein. The patient suffered from bilateral pulsatile tinnitus for 2 years. His bilateral tinnitus disappeared temporarily when the bilateral mastoid processes were compressed. Temporal bone computed tomographic (CT) showed the bilateral dilated mastoid emissary canals. Cranial Magnetic resonance venograms (MRV) showed the bilateral dilated mastoid emissary veins. We explained the risk of surgery to the patient. Because the patient could tolerate his tinnitus and did not have a hemangioma or tumor, he did not choose to undergo surgery.

Management of vascular causes of pulsatile tinnitus

Pulsatile tinnitus is a debilitating symptom affecting millions of Americans and can be a harbinger of hemorrhagic or ischemic stroke. Careful diagnostic evaluation of pulsatile tinnitus is critical in providing optimal care and guiding the appropriate treatment strategy. When a vascular cause of pulsatile tinnitus has been established, attention must be focused on the patient's risk of hemorrhagic stroke, ischemic stroke, or blindness, as well as the risks of the available treatment options, in order to guide decision-making. Herein we review our approach to management of the vascular causes of pulsatile tinnitus and provide a literature review while highlighting gaps in our current knowledge and evidence basis.

Neurosurgical Causes of Pulsatile Tinnitus: Contemporary Update

Traditionally in the domain of the otolaryngologist, pulsatile tinnitus (PT) has become increasingly relevant to neurosurgeons. PT may prove to be a harbinger of life-threatening pathology; however, often, it is a marker of a more benign process. Irrespectively, the neurosurgeon should be familiar with the many potential etiologies of this unique and challenging patient population. In this review, we discuss the myriad causes of PT, categorized by pulse-phase rhythmicity.

Venous Causes of Pulsatile Tinnitus: Clinical Presentation, Clinical and Radiographic Evaluation, Pathogenesis, and Endovascular Treatments: A Literature Review

Tinnitus is an abnormal perception of a sound without external stimulation. Venous pulsatile tinnitus (VPT) is a specific form of tinnitus characterized by an objective and often subjective bruit that occurs as a result of localized venous abnormalities. Clinical evaluation relies on sound quality, duration, and precipitating factors. Idiopathic intracranial hypertension (IIH) and transverse sinus stenosis (TSS) are among the most common causes of VPT. Other causes include sigmoid sinus wall abnormalities (SSWAs), jugular vein anomalies (JVAs), and emissary veins anomalies. These anomalies can be detected on magnetic resonance imaging, magnetic resonance angiography/magnetic resonance venography, and high-resolution temporal bone computed tomography. The pathogenesis behind the VPT includes turbulent blood flow as a result of luminal stenosis or abnormal dilation, amplification of internal sound due to temporal bone defects, and abnormal position of the venous sinus system structures adjacent to the bony structures of the auditive apparatus. Based on these theories, different interventional treatment modalities can be applied to treat the underlying causes. Endovascular treatments have shown high efficacy and safety among those treatments which include stenting of the lateral sinus stenosis in IIH and TSS, coiling of the SSWA and JVA, and embolization of emissary veins anomalies. Further studies are needed to understand the natural history of these anomalies and the efficacy of treatments of VPT, which-unlike other types of tinnitus-can be cured with proper treatment.

State of the Art: Venous Causes of Pulsatile Tinnitus and Diagnostic Considerations Guiding Endovascular Therapy

Venous variants and pathologic abnormalities are the most common causes of pulsatile tinnitus. These conditions include causes of turbulence within normally located veins and sinuses, and abnormally enlarged or abnormally located veins in close transmissive proximity to the conductive auditory pathway. Such disorders include pathologic abnormalities of the lateral sinus (transverse sinus stenosis and sigmoid sinus wall anomalies), abnormalities and variants of the emissary veins, and anomalies of the jugular bulb and jugular vein. Despite being the most common causes for pulsatile tinnitus, venous variants and pathologic abnormalities are often overlooked in the workup of pulsatile tinnitus. Such oversights can result in delayed patient care and prolonged patient discomfort. Advances in both cerebrovascular imaging and endovascular techniques allow for improved diagnostic accuracy and an increasing range of endovascular therapeutic options to address pulsatile tinnitus. This review illustrates the venous causes of pulsatile tinnitus and demonstrates the associated endovascular treatment. © RSNA, 2021.