Pulsatile Tinnitus and the Intrameatal Vascular Loop: Why Do We Not Hear Our Carotids?

Abstract

Vascular loops in the internal auditory canal may generate pulsatile tinnitus. It may be treated by placing Teflon between the cochlea and the intrameatal vascular loop. One then does not hear the pulsation of the carotids due to a dampening effect of a pericarotid venous plexus.

Vascular Loops at the Cerebellopontine Angle: Is There a Correlation with Tinnitus?

“…The anatomic course and complex vascular relationships of cisternal and canalicular parts of the eighth CN have been visualized successfully by using the 3D-FIESTA sequence. 6,9,11,14 The neurovascular compression of the eighth CN can produce vertigo, tinnitus, or hearing disturbances or various combinations of them, unlike vascular compression of the trigeminal or facial nerve. This complicated symptomatology makes vascular compression syndromes of the eighth CN difficult to understand.…”

“…[6][7][8][9]16 In their 2 articles involving a retrospective analysis of patients who had undergone surgical decompression, Ryu et al 7,8 proposed the concept of neurovascular compression syndrome of the eighth CN and recommended early decompression before irreversible impairment of the nerve function occurred. Similarly, Nowé et al 6 stated that nonpulsatile tinnitus may result from a microvascular compression at the cisternal segment of the eighth CN and showed a correlation between the clinical presentation of nonpulsatile tinnitus (high and low pitch) and perceptive hearing loss.…”

“…4,5 Compression of the eighth cranial nerve (eighth CN) by vascular structures has been proposed as a cause of tinnitus. [6][7][8][9][10] However, controversial results have been reported in the medical literature about the relationship between neurovascular compression of the eighth CN and neuro-otologic symptoms. [11][12][13][14] The purpose of our study was to assess the correlation between the presence of a vascular loop and its contact with the eighth CN in the cerebellopontine angle (CPA) and ipsilateral symptoms of unexplained tinnitus by using a 3D fast imaging employing steady-state acquisition (3D-FIESTA) sequence, which is an MR imaging technique that provides good contrast between CSF, nerves, and vessels.…”

Microvascular Compression of the Vestibulocochlear Nerve

“…Vascular loops inside the internal acoustic meatus along the morphologically more resistant peripheral nervous system (PNS) segment, however, were described to produce either typewriter tinnitus [43] or pulsatile tinnitus [41,44]. Typewriter tinnitus consists of paroxysms of tinnitus perceived as Morse code, machine gun-like staccato, or typewriter sound and has been shown to be responsive to treatment with carbamazepine [43], thus analogous to trigeminal neuralgia.…”

Pulsatile Tinnitus

“…Hyperdynamic flow in the internal carotid artery can generate pulsatile tinnitus, as seen in basilar artery atresia with predominant flow in both carotids [42]. The hyperdynamic flow can also be due to anemia [43], thyrotoxicosis, or pregnancy.…”