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Various imaging strategies have been proposed for
the investigation of PT in the otoscopically normal
patient and they continue to evolve. MRI (with
gadolinium), MR angiography (MRA), MR venogra-
phy (MRV), carotid ultrasound, CT with and without
contrast medium, and conventional angiography
have all been used rather inconsistently in
previous patient series. Combined CT angiography
and venography (CTA/V) may be performed with
100 ml contrast medium injected at 3
e
4 ml/s and
a fixed delay of 25 s using contemporary multisec-
tion CT. This approach shows considerable promise
and has the advantage of demonstrating arterial,
venous, skull-base, and middle-ear disease entities
Table 1
Reported incidence of structural abnormalities in patients investigated for all causes of pulsatile tinnitus
Author
Waldvogel
4
Sonmez
5
Remley
6
Krishnan
7
Dietz
8
Sismanis
9
Total no. of patients (Percentage
with objective tinnitus)
84 (42%)
74 (15%)
100 (25%)
16 (6%)
49 (33%)
145 (8%)
Investigations
a
Ultrasound
68
12
Not stated
Computed tomography
26
72
69
10
Magnetic resonance imaging
33
7
24
49
Magnetic resonance angiography
7
7
49
Selective angiography
46
5
68
17
CTA/V
16
Cause found
57 (68%)
50 (68%)
80 (80%)
7 (44%)
28 (57%)
132 (91%)
Vascular anomaly
Aberrant ICA
1 (1%)
8 (8%)
Dehiscent jugular bulb
3 (4%)
5 (5%)
1 (2%)
High-riding jugular bulb
21 (28%)
7 (7%)
1 (6%)
JB/transverse sinus diverticulum
1 (1%)
1 (1%)
1 (6%)
2 (4%)
Enlarged cortical draining vein
1 (1%)
1 (2%)
Vascular loop
1 (1%)
1 (1%)
Vascular tortuosity
6 (4%)
Dominant venous system
b
6 (38%)
Acquired vasculopathy
Dural AVF
17 (20%)
2 (3%)
15 (15%)
3(%)
Pial AVF
9 (18%)
Carotico-cavernous fistula
6 (7%)
1 (2%)
Atheromatous ICA disease
7 (8%)
16 (22%)
5 (5%)
Fibromuscular dysplasia
5 (6%)
4 (4%)
2 (4%)
ICA aneurysm
1 (1%)
3 (4%)
2 (2%)
2 (1%)
ICA dissection
1 (1%)
Extracranial AVF/M
1 (2%)
1 (1%)
1 (2%)
Venous sinus thrombosis
1 (1%)
Tumour
Paraganglioma
5 (6%)
2 (3%)
25(25%
17 (12%)
Meningioma
1 (1%)
2 (2%)
5 (10%)
Other
1 (1%)
1 (1%)
2 (2%)
1 (1%)
Idiopathic intracranial hypertension
4 (5%)
2 (4%)
56
c
(39%)
Venous sinus stenosis
1 (1%)
1 (6%)
Other
Otospongiosis
4 (3%)
Myoclonus
1 (1%)
Systemic causes
1 (1%)
10 (8%)
No aetiology found in patients
with objective tinnitus (%)
7 (8%)
0
0
Not stated 0
Not stated
CTA/V, computed tomography angiography/venography; ICA, internal carotid artery; AVF, arteriovenous fistulae.
a
Some patients underwent multiple investigations.
b
Association with the venous sinus dominance is speculative.
c
Four other patients had radiographic features of idiopathic intracranial hypertension but declined lumbar puncture.
G. Madani, S.E.J. Connor
70