What is Pulsatile Tinnitus?

Introduction

Have you, at some point in your life, perceived a distinct sound in your ear and realised it does not derive from external sources? This auditory symptom is commonly referred to as tinnitus, manifesting as ringing, buzzing, or a steady pulsatile sound and varies in intensity and duration.

There are two broad types of tinnitus; subjective tinnitus, which involves acoustic symptoms despite a lack of external stimuli and is undetectable by others; and objective tinnitus, characterised by an internal generation of sound that can be detected through audiometric tests. 

Subjective tinnitus is a common phenomenon and can be experienced after prolonged exposure to loud environments, like construction sites or concerts. In contrast, objective tinnitus is less common and usually originates from dysregulations in the muscular, skeletal, vascular, or respiratory systems.^1,2

Tinnitus is further categorised into non-pulsatile and pulsatile types. The former involves the perception of continuous noises in the ear, while pulsatile tinnitus (PT) refers to a whooshing sound or rhythmic beat, frequently in synchronisation with the individual’s heartbeat.³ Despite tinnitus affecting over 50 million people in Europe, the exact underlying causes of it remain incompletely understood.⁴

PT, which makes up less than 5% of all cases, arises mainly from vascular disorders that provoke the auditory system similarly to an external auditory stimulus.⁵ This phenomenon is described as a fatiguing symptom that can significantly interfere with daily life, influencing routine tasks and even disrupting sleep quality. While hypertension might be the leading cause of PT, identifying the precise origin of this phenomenon is crucial for effectively managing this condition and alleviating symptoms.

Factors contributing to pulsatile tinnitus and underlying conditions

With the goal of effective treatment and symptom alleviation in patients, experts have investigated possible causes of pulsatile tinnitus by examining patient physiology. There is a strong emphasis on examining vascular structures such as the arterial and venous systems as they often play key roles in PT development. Additionally, abnormalities in muscular mechanisms as well as neoplastic conditions in or near the auditory system have also been investigated and linked to PT.⁵

Vascular causes

PT has been linked to a wide spectrum of vascular conditions that can be categorised as follows:

Venous causes

A range of different venous pathological conditions have been implicated in the development of PT.  Some examples include:⁶

• Idiopathic intracranial hypertension: This condition has a relatively high incidence in overweight premenopausal women, with one of its prominent symptoms being PT, accompanied by headaches and progressive visual loss.
• Venous sinus stenosis: Individuals with this condition have impaired and turbulent blood flow through the head and neck, resonating in or near the ears. Notably, transverse or sigmoid stenosis and aberrations in sinus wall anatomy are associated with PT.
• Jugular vein abnormalities: These anomalies are characterised by an altered turbulent blood flow in specific locations that can produce PT.

Arterial causes

Numerous vascular comorbidities affecting the arterial system can lead to PT, including:

• Dural arteriovenous fistula: This condition refers to an irregular network between a vein and an artery within a dural sinus, a blood channel responsible for draining deoxygenated blood from the head. Occlusion in the dural sinus, along with the generation of alternative vascular networks as a compensatory mechanism, results in high blood flow in the area that may cause PT.⁷
• Internal carotid artery abnormalities: Alterations in the anatomical structure of the internal carotid artery, carotid artery stenosis or dissection, and atherosclerotic carotid artery disease are all high-risk conditions associated with PT.^8,9
• Fibromuscular dysplasia: This idiopathic condition is characterised by a narrowing in the carotid arteries, resulting in turbulent blood flow echoing in the temporal bone and is perceived as PT.⁷

Neoplastic causes

The most common neoplastic cause of PT includes the presence of glomus tumours in the temporal lobe, also known as paragangliomas. These tumour masses affect the middle ear cavity (glomus tympanicum), the jugular bulb (glomus jugulare), or both (glomus jugulotympanicum). These masses typically exhibit a strong contrast in MRI images and have the potential to invade adjacent nerves, vascular structures, and cavities, consequently leading to PT.³

Further, benign tumours within the haemangioma group, situated in the internal auditory canal, the geniculate ganglion, or the middle ear cavity, can also contribute to PT.³

Muscular causes

Although uncommon, muscular causes can be attributed to PT, arising from myoclonic contractions originating within the ear or its proximity. These contractions are not correlated with a pulse-synchronised PT and can be due to myoclonic activity in the middle ear, the palate, or the Eustachian tube.⁵

Miscellaneous causes

Additional factors contributing to PT encompass multiple conditions, including specific diseases such as Paget’s disease of the bone, which predominantly affects older individuals. Moreover, other systemic dysregulations like hypertension, anaemia, and hyperthyroidism can also result in PT by augmenting cardiac output.⁵ Furthermore, head trauma or specific medications may also be related to PT.¹⁰

Symptoms and diagnosis

Recognising pulsatile tinnitus by reported symptoms

Symptom intensity and length vary significantly among individuals with PT. Several case reports available online detail distinct patient profiles who have described symptoms as hearing whooshing tones synchronised with their heartbeat. Additional mentionable neurological symptoms are crucial considerations for an accurate diagnosis. The following symptoms have been reported by patients with PT:^5,10

• Unilateral or bilateral PT
• Low, medium, or high-intensity sound
• Constant PT or intermittent sound
• Symptom variations from one week up to five years from the onset of PT
• Associated pain and tenderness in the cervical (neck) area, and headaches
• Exacerbation and alleviation with exercise or the use of headphones
• Neurological symptoms, including visual and hearing changes, and vertigo

Medical evaluation and diagnostic procedures

Audiological tests

Otorhinolaryngologists (doctors who specialise in the head and neck) initiate the evaluation of PT by obtaining a thorough medical history and chronic medication list from patients to assess any potential association of a patient's known conditions with this symptom. A detailed description of the perceived sound is crucial for practitioners to differentiate and diagnose the correct type of tinnitus. An investigation of further neurological symptoms is also part of the initial assessment.⁷

A physical exam is decisive for distinguishing between subjective and objective PT. A head and neck examination, by conducting otoscopic procedures, cranial nerve examination, and tone fork tests, is essential for identifying the underlying causes of PT. 

Otoscopy is selected to assess the presence of tumour masses or other anomalies in the middle ear. An auscultation of a vascular bruit could signify a vascular cause, while palpation by compressing arterial or venous structures aids in differentiating arterial or venous origins. Head rotations and specific manoeuvres, such as the Valsalva manoeuvre, may be conducted to check symptom modulation.^7,10

Further investigations include audiometric tests, where a frequency loss could indicate idiopathic intracranial hypertension as a potential cause of PT.¹⁰

Cardiac and blood tests

Following physical tests, a comprehensive heart examination and blood tests will guide clinicians in inspecting possible causes of PT. Cardiac and cervical auscultations are performed, especially using Doppler scans, when carotid stenosis or other cervical artery aberrations are suspected.^5,10

Blood pressure testing, measurement of vital signs, and BMI calculations are also performed. Blood tests to check for anaemia, hyperthyroidism, and cholesterol levels are also calculated to evaluate the risk of atherosclerosis.⁵

Imaging studies

If practitioners find it necessary, imaging testing is conducted, using magnetic resonance angiography or venography and computed tomography angiography scans. These practices help identify vascular abnormalities that may result in PT.¹⁰

Treatment options

Treatment options for PT depend on accurately recognising the underlying causes. Whether the PT originates from vascular, tumoural, or other metabolic disorders, clinicians will target these conditions to alleviate PT symptoms. Additionally, therapeutic practices with a behavioural focus have also been established as adjuvant therapies for PT, including:

• Tinnitus retraining therapy: The goal of this therapy is to reduce PT-induced stress in patients. Experts themselves, or through the use of smart devices, educate individuals with chronic and persistent PT to alleviate stress symptoms that can negatively impact their quality of life. Sound therapy is also integrated into this guideline to assist patients in relaxation and managing PT symptoms by redirecting focus.¹¹
• Cognitive behavioural therapy: Specialists use this approach to guide patients in gaining control over their thoughts and feelings, attempting to reduce misconceptions about PT and adapting new behaviours that could alleviate impairment due to this symptom.⁶
• Acceptance and awareness: Counselling options are available for supporting patients coping with PT.
• Stress reduction techniques: Personal adjustments and adaptation of relaxation techniques can help reduce stress levels associated with PT.

Summary

In summary, PT primarily involves hearing a steady beat in coordination with the heartbeat. While it may occur post-exercise, the sound typically subsides when the heartbeat returns to normal. However, a persistent and bothersome PT can significantly impair individuals and substantially reduce their quality of life. 

PT may also signal life-threatening comorbidities that need to be carefully evaluated. Multiple underlying disorders in the vascular and muscle systems of the head and neck can result in PT. Specific neoplastic masses have also been linked to it. 

Therapeutic approaches involving medications, specialised therapies, or even surgery are the primary strategies of experts. Adjuvant therapies with a psychological aspect are also available, underscoring the importance of adopting a personalised therapeutic approach that suits the personal needs and feelings of each individual.

Although not all underlying causes of PT can be prevented, certain strategies such as regular health check-ups, hearing protection and awareness are important. If you have experienced PT or are unsure about it, scheduling an appointment with your doctor could set your mind at ease. Clear communication about your symptoms with your doctor is vital for them to assess your condition and effectively distinguish your symptoms to address the underlying problem.