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PICTORIAL REVIEW
Imaging in pulsatile tinnitus
G. Madani
a
,
*
, S.E.J. Connor
b
a
Radiology Department, St Mary’s Hospital, London, UK, and
b
Neuroradiology Department,
King’s College Hospital, London, UK
Received 11 January 2008; received in revised form 17 July 2008; accepted 1 August 2008
Tinnitus may be continuous or pulsatile. Vascular lesions are the most frequent radiologically demonstrable cause of
pulsatile tinnitus. These include congenital vascular anomalies (which may be arterial or venous), vascular tumours,
and a variety of acquired vasculopathies. The choice of imaging depends on the clinical findings. If a mass is present at
otoscopy, thin-section computed tomography (CT) is indicated. In the otoscopically normal patient, there is a range of
possible imaging approaches. However, combined CT angiography and venography is particularly useful.
ª
2008 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
Introduction
Tinnitus is the perception of an auditory sensation,
most frequently a ringing sound, in the absence of an
external stimulus. Tinnitus may be classified as
pulsatile (PT) or continuous. PT is usually related to
vascular causes and is pulse-synchronous (coinciding
with the patient’s heartbeat). It may be subjective
(heard only by the patient) or objective (also audible
to the examiner).
The prevalence of persistent tinnitus (lasting
more than 5 min) in the UK adult population is
around 10%; half of these patients find the symp-
tom moderately or severely annoying.
1
PT is much
less common than non-PT, affecting approximately
4% of patients with tinnitus.
2
PT may not require
radiological investigation; cases may be transient,
related to drugs, systemic processes (e.g. hyper-
tension, anaemia, pregnancy), or other conditions,
such as migraine.
Radiological investigation aims to find treatable
causes of tinnitus. In the setting of non-PT, the
main entity to exclude is a cerebellopontine cis-
tern mass lesion. In the absence of additional
audiological findings, the diagnostic yield of
radiological investigation of non-PT is low and
thin-section, T2-weighted magnetic resonance im-
aging (MRI) sequences are generally used for
screening.
3
Thus knowledge of the nature of the
tinnitus (PT versus non-PT) is essential.
There is a wide variation in the reported in-
cidence of structural abnormalities in patients
with PT ranging from 44
e
91% (
Table 1
).
4
e
9
This is
likely to reflect variations in the study populations,
expertise, and methods of investigation. Paragan-
gliomas, dural arteriovenous fistulae (dAVFs), idio-
pathic intracranial hypertension (IIH), venous
anatomical variations, and atheromatous arterial
disease represent the most frequent causes.
4
e
9
An underlying cause is usually identified in patients
with objective tinnitus (
Table 1
).
4
e
9
This review focuses on the radiological imaging of
PT. The choice and focus of imaging for PT is guided
by the clinical findings. The presence of a visible
intratympanic or retrotympanic mass and the sus-
picion of arterial [reduced by pressure on the
ipsilateral internal carotid artery (ICA)] or venous
(reduced by pressure on the ipsilateral jugular vein)
aetiologies are particularly important.
Radiological investigation
If a mass is seen at otoscopy, then a thin-section
computed tomography (CT) of the petrous tempo-
ral bones is needed to assess the middle ear.
* Guarantor and correspondent: G. Madani, Radiology Depart-
ment, St Mary’s Hospital, Imperial College NHS trust, Praed
Street, London W2 1NY, UK. Tel.:
þ
44-2078861116; fax:
þ
44-
2078872281.
E-mail address:
gittamadani@yahoo.com(G. Madani).
0009-9260/$ - see front matter
ª
2008 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
doi:10.1016/j.crad.2008.08.014
Clinical Radiology (2009)
64
, 319
e
328
Reprinted by permission of Clin Radiol. 2009; 64(3):319-328.
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