The perception of a rhythmic “whooshing” or pulsing sound in the ear, often synchronized precisely with one’s heartbeat, is known as pulsatile tinnitus. This noise is frequently amplified or only becomes apparent when a person lies down, which can be alarming and disruptive to sleep. Pulsatile tinnitus represents a physical sound occurring within the body that is being heard, rather than a phantom auditory perception. While the symptom itself can cause anxiety, it always warrants a medical evaluation to identify the source of the sound.
Understanding the Positional Nature of the Sound
The characteristic worsening of the whooshing sound when lying down is directly related to changes in hemodynamics, the movement of blood within the circulatory system. When the body shifts from an upright to a horizontal position, gravity’s effect on blood flow changes significantly. Lying down increases the volume of blood returning to the heart and elevates the overall blood pressure within the vessels of the head and neck. This change in posture temporarily increases the speed and turbulence of blood flow through veins and arteries near the ear structures.
The inner ear is situated in close proximity to large blood vessels like the jugular veins and carotid arteries. As blood flow increases in these vessels upon lying down, the sound produced by this rushing blood is mechanically conducted through the surrounding bone and tissue. This allows the sound, which may be inaudible when standing, to become loud enough to be perceived in the quiet environment of a bedroom.
Common Non-Vascular Explanations
Not all causes of pulsatile tinnitus are related to changes in blood vessel flow; sometimes, the issue lies in the ear’s ability to transmit or amplify normal body sounds. A common non-vascular cause is conductive hearing loss, such as excessive earwax (cerumen impaction) or fluid buildup behind the eardrum from a middle ear infection. These blockages prevent external sounds from entering the ear canal, effectively lowering the ambient noise level and allowing internal body sounds, like the pulse, to become more noticeable.
Another non-vascular source originates from muscle spasms, known as myoclonus, in the tiny muscles attached to the middle ear bones or the palate. Spasms of the tensor tympani or stapedius muscles can create a repetitive clicking or thumping sound that may be mistaken for a pulse. Dysfunction of the temporomandibular joint (TMJ), located immediately in front of the ear, can also cause muscle tension that transmits mechanical noise to the auditory system. Patulous Eustachian tube dysfunction, where the tube remains abnormally open, allows the sound of breathing and internal circulation to travel directly into the middle ear.
Vascular Sources of Pulsatile Tinnitus
The causes of pulsatile tinnitus often involve the vascular system, creating audible turbulence in blood flow.
Venous Causes
One common venous cause is the venous hum, which occurs when blood flows rapidly through the large jugular veins in the neck. This sound is often exacerbated when lying down because the change in posture increases the pressure and volume of blood in these large veins. The sound may disappear when the jugular vein is lightly compressed.
Arterial Causes
Arterial causes involve conditions that disrupt the smooth flow of blood, forcing it into a noisy, turbulent pattern. Narrowing of the carotid arteries in the neck, often due to the buildup of fatty plaques (atherosclerosis), creates a constriction that forces blood through a smaller opening. This generates a distinctive whooshing noise that is easily transmitted to the nearby hearing structures. High blood pressure (hypertension) can also increase the force with which blood is pumped, amplifying the sound of flow throughout the head and neck vessels.
Anatomical and High-Flow Conditions
Certain anatomical variations or conditions involving high-flow areas can also be responsible for the sound. Idiopathic Intracranial Hypertension (IIH) involves elevated pressure of the cerebrospinal fluid surrounding the brain, and is a significant cause of pulsatile tinnitus, particularly in younger, overweight women. This increased pressure often causes a narrowing of the large veins in the brain (transverse sinuses), which restricts blood outflow and creates a turbulent hum that is frequently bilateral and worse when supine. Rarely, highly vascular tumors, such as paragangliomas located near the middle ear or skull base, can create a loud, pulsating noise due to the massive flow of blood through the tumor’s network of vessels.
Medical Evaluation and Diagnosis
Any new onset of pulsatile tinnitus requires a professional medical assessment, especially if accompanied by symptoms like dizziness, severe headache, or changes in vision. The diagnostic process begins with a detailed history and a physical examination by a physician or an otolaryngologist. During the examination, the clinician may perform auscultation, using a stethoscope to listen over the neck, ear, and skull to determine if the sound is “objective,” meaning the doctor can hear it too.
If a vascular cause is suspected, specialized imaging tests are necessary to visualize the blood vessels and surrounding structures.
- Magnetic Resonance Angiography (MRA) and Computed Tomography Angiography (CTA) use advanced imaging to create detailed pictures of the arteries and veins in the head and neck. These studies identify narrowing (stenosis) of the carotid arteries, anatomical anomalies of the jugular veins, or the presence of a vascular tumor.
- A specialized hearing test (audiogram) checks for conductive hearing loss.
- Blood work rules out systemic conditions like anemia or thyroid dysfunction, which can increase blood flow noise.
- If Idiopathic Intracranial Hypertension (IIH) is suspected, an ophthalmologist checks the eyes for optic nerve swelling, and a spinal tap measures cerebrospinal fluid pressure.
Identifying the precise underlying cause determines the correct treatment, which may range from lifestyle changes to medical management or surgical intervention.