PhiliPPine Journal of otolaryngology-head and neck Surgery Vol. 33 no. 2 July – december 2018
PhiliPPine Journal of otolaryngology-head and neck Surgery 6160 PhiliPPine Journal of otolaryngology-head and neck Surgery PhiliPPine Journal of otolaryngology-head and neck Surgery 6160 PhiliPPine Journal of otolaryngology-head and neck Surgery
FROM THE VIEWBOX
Pulsatile Tinnitus Due to a Sigmoid Sinus
Diverticulum and/or Dehiscence
In 2009, a 52-year-old man presented with a two-year history of intermittent right-sided
pulse-synchronous tinnitus. He noted that the tinnitus worsened when his blood pressure
was elevated. Otologic exam was unremarkable with no obvious middle ear fluid or mass.
There was no neck bruit and the tinnitus diminished on manual compression of the ipsilateral
internal jugular vein. In keeping with the recommendations for clinical imaging at that time, a
non-contrast CT of the temporal bone was performed. This was to evaluate for conditions such
as: a middle ear glomus, an aberrant internal carotid artery, a jugular bulb variant (e.g. a high-
riding jugular bulb), otosclerosis, superior semicircular canal dehiscence syndrome, a persistent
stapedial artery, or a hemangioma of the temporal bone.1 No evidence of these conditions was
found. An MRI of the brain, with MR angiography and venography of the intracranial vasculature
also performed to evaluate for conditions such as: idiopathic intracranial hypertension, a dural
arteriovenous fistula, an arteriovenous malformation, vascular loop syndrome and dural sinus
stenosis or thrombosis.2 All of these conditions were excluded. As no definite pathology was
identified, no firm treatment recommendations were initiallly made.
In 2011, Eisenman reported on a series of 13 patients with pulsatile tinnitus due to a
sigmoid sinus diverticulum and/or dehiscence who were successfully treated surgically via
an extraluminal transmastoid approach.3 This was the first relatively large series published in
the otologic literature. This publication likewise reported on the subtle radiologic signs that
signify the presence of a sigmoid sinus diverticulum and/or dehiscence such as an irregularity
of the normal semicircular contour of the bony sinus wall, focal thinning of the calvarial cortex
overlying the adjacent sinus wall, absence of the normal thin layer of cortical bone overlying the
sinus and the “air-on-sinus” sign where mastoid air cells directly contact the sinus wall without
overlying bone.3
In light of this new information, the patient’s imaging studies were re-evaluated and evidence
of a right-sided sigmoid sinus diverticulum and/or dehiscence was identified. The images below
show the findings on an axial slice of the patient’s temporal bone CT study.
Correspondence: Dr. Nathaniel W. Yang
Department of Otorhinolaryngology
Ward 10, Philippine General Hospital
University of the Philippines Manila
Taft Avenue, Ermita, Manila 1000
Philippines
Phone: (632) 526 4360
Fax: (632) 525 5444
Email: nathaniel.w.yang@gmail.com
The author declared that this represents original material, that
the manuscript has been read and approved by the author, that
the requirements for authorship have been met by the author,
and that the author believes that the manuscript represents
honest work.
Disclosures: The author signed a disclosure that there are no
financial or other (including personal) relationships, intellectual
passion, political or religious beliefs, and institutional affiliations
that might lead to a conflict of interest.
Philipp J Otolaryngol Head Neck Surg 2018; 33 (2): 60-61 c Philippine Society of Otolaryngology – Head and Neck Surgery, Inc.
Nathaniel W. Yang, MD
Department of Otorhinolaryngology
College of Medicine – Philippine General Hospital
University of the Philippines Manila
Department of Otolaryngology Head and Neck Surgery
FEU-NRMF Institute of Medicine
Creative Commons (CC BY-NC-ND 4.0)
Attribution - NonCommercial - NoDerivatives 4.0 International
PhiliPPine Journal of otolaryngology-head and neck Surgery 6160 PhiliPPine Journal of otolaryngology-head and neck Surgery
PhiliPPine Journal of otolaryngology-head and neck Surgery Vol. 33 no. 2 July – december 2018
PhiliPPine Journal of otolaryngology-head and neck Surgery 6160 PhiliPPine Journal of otolaryngology-head and neck Surgery
FROM THE VIEWBOX
REFERENCES
1. Mattox DE, Hudgins P. Algorithm for evaluation of pulsatile tinnitus. Acta Oto-Laryngologica
2008; 128: 427-431.
2. Shin EJ, Lalwani AK, Dowd CF. Role of angiography in the evaluation of patients with pulsatile
tinnitus. Laryngoscope 2000; 110:1916-1920.
3. Eisenman DJ. Sinus wall reconstruction for sigmoid sinus diverticulum and dehiscence: a
standardized surgical procedure for a range of radiographic findings. Otol Neurotol 2011; 32:
1116-9.
4. Schoeff S, Nicholas B, Mukherjee S, et al. Imaging prevalence of sigmoid sinus dehiscence
among patients with and without pulsatile tinnitus. Otolaryngol Head Neck Surg 2014; 150: 841-
46.
Figure 1. Axial CT image of the temporal bone at the level of the horizontal semicircular canals : absence of the normal thin layer of
cortical bone overlying the right sigmoid sinus (white arrow) compared to the left sigmoid sinus
Figure 3. Magnified view of Figure 1 showing the “air-on-sinus” sign, where the mastoid
air cell directly contacts the sinus wall, without any overlying bone (white arrow)
Figure 2. Axial CT of the temporal bones: the location of the sigmoid sinus outlined with the red dotted line, illustrating the irregularity
in the normal semicircular contour of the bony sinus wall. A portion of the sigmoid sinus can be seen extending beyond the seeming
border of the sigmoid sinus.
How significant is this condition ? Sigmoid sinus diverticulum and/
or dehiscence is being increasingly recognized as a common cause
of pulsatile tinnitus. In fact, a recent study by Schoeff et al. found its
prevalence to be 23% in patients with pulsatile tinnitus.4 As such, the
identification of this condition is highly relevant particularly because
effective surgical management is available for its alleviation.