The perception of sound within the ear when no external source is present is broadly known as tinnitus. While most people associate this condition with a constant ringing, buzzing, or hissing, a less common variant is pulsatile tinnitus (PT). PT is often described as a whooshing or thumping noise that follows a rhythm, frequently mirroring the individual’s heartbeat. Given the proximity of ear structures to major blood vessels, it is important to understand if temporary conditions, such as an ear infection, can trigger this rhythmic sound. This article details the mechanical pathways connecting PT to ear infections, provides context on other common causes, and outlines necessary steps for medical evaluation.
Defining Rhythmic Tinnitus
Pulsatile tinnitus (PT) is characterized by the perception of a rhythmic sound synchronized with the cardiac pulse. Individuals typically describe this sound as a throbbing, whooshing, or steady beat, which can be confirmed by checking their pulse. This synchronization differentiates PT from the more common form of tinnitus, which usually presents as a steady, high-pitched ringing or static noise.
PT is often classified as objective tinnitus, meaning a physician may also be able to hear the sound using a stethoscope placed near the ear or neck. This indicates a physical sound is being generated within the body. In contrast, the typical ringing tinnitus is considered subjective, meaning only the patient can perceive the sound. The rhythmic nature of PT suggests it is more likely to have an identifiable physical or mechanical source that can be diagnosed and potentially treated.
The Mechanical Link to Ear Infections
An ear infection, particularly otitis media, can cause pulsatile tinnitus through a mechanical process. The middle ear is an air-filled chamber located behind the eardrum that contains the tiny bones responsible for transmitting sound. When an infection occurs, the eustachian tube, which connects the middle ear to the back of the nose, often becomes blocked.
This blockage prevents proper ventilation and drainage, leading to the accumulation of fluid, known as middle ear effusion. The presence of this fluid changes the acoustic properties of the middle ear, creating temporary conductive hearing loss. This muffles external sounds, reducing the masking effect that normal ambient noise provides.
The dampening of outside sounds makes the body’s normal internal sounds significantly more noticeable. The prominent internal sound amplified is the turbulent flow of blood through nearby vessels, such as the carotid artery and the jugular vein. The fluid-filled middle ear acts as an acoustic amplifier for these normal, rhythmic vascular sounds, which the patient perceives as pulsatile tinnitus.
Once the infection resolves and the middle ear fluid dissipates, the normal acoustic insulation returns, and the pulsatile sound typically fades. This temporary nature helps distinguish PT caused by middle ear fluid from more chronic causes.
Other Causes of Pulsatile Tinnitus
The majority of pulsatile tinnitus cases are related to changes in blood flow or vascular structures near the ear. These causes can be categorized into vascular issues, systemic conditions, and structural abnormalities.
- Atherosclerosis: Plaque buildup inside arteries narrows the vessels, causing blood flow to become turbulent and louder as it rushes past the restriction.
- Systemic Conditions: Conditions that increase the speed or volume of blood flow, such as severe anemia or hyperthyroidism, accelerate the heart rate and lead to faster, audible blood flow.
- Benign Intracranial Hypertension (BIH): Increased pressure inside the skull can compress the large veins that drain blood from the brain. This compression disrupts smooth venous flow, causing a loud, rhythmic sound.
- Vascular Tumors: Rare tumors near the ear, such as glomus tumors, are highly vascular and can generate their own audible flow noise or press against other vascular structures.
When to Seek Medical Evaluation
Any new onset of pulsatile tinnitus warrants a medical evaluation to determine the underlying cause and rule out potentially serious conditions. The first step involves consulting an otolaryngologist (ENT specialist). During the examination, the physician will take a thorough history and may attempt to listen to the sound using a stethoscope, which helps confirm the objective nature of the tinnitus.
Diagnostic testing typically begins with a comprehensive hearing test (audiogram) to identify any accompanying hearing loss. If the physical exam does not reveal a clear, benign cause like an infection, imaging studies are often necessary. These may include magnetic resonance imaging (MRI), computerized tomography (CT) scans, or specialized vascular imaging (MRA or MRV) to visualize the arteries and veins in the head and neck.
Treatment depends entirely on the underlying issue identified. If the cause is a middle ear infection, antibiotics or observation may resolve the fluid buildup and eliminate the sound. If a systemic issue like anemia or high blood pressure is found, treatment focuses on medical management of that condition. For structural or vascular abnormalities, a specialist may recommend procedures such as stenting or, in rare cases, surgical intervention.