Patulous Eustachian tubes can be associated with tinnitus. The Eustachian tube is a small canal that connects the middle ear to the back of the nose and upper throat. The Eustachian tube normally remains closed. In individuals with a patulous Eustachian tube, the tube is abnormally open. Consequently, talking, chewing, swallowing and other similar actions can cause vibrations directly onto the ear drum. For example, affected individuals may hear blowing sounds that are synchronized with breathing.
The most common noise is the sound of rapid or turbulent blood flow in major vessels of the neck. This abnormal blood flow may occur because of a reduced red blood cell count (anemia) or a blockage of the arteries (atherosclerosis) and may be worsened in people with poorly controlled high blood pressure (hypertension). Some small tumors of the middle ear called glomus tumors are rich in blood vessels. Although the tumors are small, they are very near the sound-receiving structures of the ear, and blood flow through them can sometimes be heard (only in one ear). Sometimes, blood vessel malformations that involve abnormal connections between arteries and veins (arteriovenous malformations) develop in the membrane covering the brain (the dura). If these malformations are near the ear, the person sometimes can hear blood flowing through them.
Research shows a frequent correlation between tinnitus and hearing loss. Because tinnitus is perceived differently by each sufferer, an exact diagnosis is essential. A doctor may conduct ENT, dental, orthodontic, and orthopedic examinations in order to establish whether a case can be medically treated or not. The pitch and volume of tinnitus can be determined by special diagnostic test, and a hearing test can reveal whether hearing loss is also involved. Treatment with hearing aids is often the first step to relief from tinnitus. Hearing aids compensate for hearing loss, which enables concentration on external sounds instead of internal noises.
Generally, following the initial evaluation, individuals suspected of rhythmic tinnitus will undergo some form of specialized medical imaging. Individuals may undergo high resolution computed tomography (HRCT) or magnetic resonance angiography (MRA) to evaluate blood vessel abnormalities such as a vascular malformation that may be the cause of tinnitus. An HRCT scan can also be used to evaluate the temporal bone for sinus wall abnormalities and superior semicircular canal dehiscence. HRCT uses a narrow x-ray beam and advanced computer analysis to create highly detailed images of structures within the body such as blood vessels. An MRA is done with the same equipment use for magnetic resonance imaging (MRI). An MRI uses a magnetic field and radio waves to produce cross-sectional images of particular structures or tissues within the body. An MRA provides detailed information about blood vessels. In some cases, before the scan, an intravenous line is inserted into a vein to release a special dye (contrast). This contrast highlights the blood vessels, thereby enhancing the results of the scan.
Atherosclerosis. With age and buildup of cholesterol and other deposits, major blood vessels close to your middle and inner ear lose some of their elasticity — the ability to flex or expand slightly with each heartbeat. That causes blood flow to become more forceful, making it easier for your ear to detect the beats. You can generally hear this type of tinnitus in both ears.