Sigmoid sinus diverticulum
Results
The patients ranged in age from 14- 70 years. There were 11 females and 2
males, with 15 affected ears, 14 of which underwent surgery. The symptoms had
been present from 3 months to greater than 10 years; symptom duration is
unknown for 3 patients. There were 12 right ears and 2 left ears. One patient who
had surgery on the right for unilateral PST, noticed a less intense left PST
immediately upon resolution of the right ear symptoms. In retrospect, a smaller
diverticulum was evident on the left that was overlooked pre-operatively. She has
not chosen to undergo repair on the left. One of the patients who had left ear
surgery had previously undergone a successful repair on the right 2 years prior. All
of the patients had complete resolution of their PST post-operatively. The majority
had resolution noted immediately upon awakening in the Post-Anesthesia Care Unit,
though 3 patients had a delayed recovery over the ensuing 2-3 weeks. Of these, 2
had reconstruction with bone pate alone, and 2 had dehiscence alone without
diverticulum formation. Median follow-up is 11.5 months (range 3-41.5 months),
and there have been no recurrences over this time period.
There have been two major complications. Patient #4 presented to an
outside hospital 24 hours post-operatively with acute visual loss. Her pre-operative
finding was of dehiscence of the sinus wall, without diverticulum formation, and the
procedure went uneventfully (Figs. 4a, b). Her tinnitus had been present for 10
weeks, and was objectively audible pre-operatively with a Toynbee tube placed in
the external auditory canal. She had a mild, rising right sensorineural hearing loss
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Sigmoid sinus diverticulum
with 100% word recognition and absent probe-left acoustic reflexes. There was no
history of aural fullness, tinnitus or vertigo. The procedure went uneventfully. The
PST was gone immediately post-operatively, and remained absent 26 months later
at her most recent follow-up. The weight was 63.5 kilograms, and no pre-operative
history of symptoms consistent with pseudotumor was obtained. The vision on
presentation to the outside hospital post-operatively was recorded at 20/200,
bilaterally and fundoscopic examination demonstrated severe bilateral papilledema.
There was no complaint of headache, nausea or vomiting post-operatively to
suggest an acute increase in intracranial pressure. Lumbar puncture demonstrated
a markedly elevated opening pressure of approximately 200 mmHg. Magnetic
resonance angiography, and subsequent computed tomographic venography
demonstrated no evidence of dural venous sinus outflow obstruction (Fig. 4c), and
an MRI demonstrated no optic nerve or cerebral edema and no venous infarction.
The patient was treated in the outside hospital with anticoagulation, bilateral optic
nerve sheath decompression and placement of a ventriculo-peritoneal shunt. Her
vision ultimately returned to normal, and she has had no long-term consequences
from the complication. With no other evidence of an acute rise in intracranial
pressure, and with no venous sinus obstruction, the etiology of her complication is
unclear. We have not excluded the possibility that she had a pre-operative elevation
in her intracranial pressure.
Patient #14 had progressive headache starting immediately post-operatively.
There was no complaint of altered visual acuity, nausea or vomiting. She was seen
on post-operative day #10 for routine care, and the wound looked healthy, though
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Sigmoid sinus diverticulum
her headache persisted and she now complained of contralateral PST. The next day
she presented to the Emergency Department with persistent headache. Magnetic
resonance angiography (MRA) was performed, and demonstrated no flow in the
ipsilateral transverse and sigmoid sinuses. (Fig. 5a) The torcula and contralateral
sinuses were patent, as were both internal jugular veins. Computed tomography
demonstrated no evidence of extraluminal compression of the sinus by the
reconstruction. (Fig. 5b) Fundoscopic exam demonstrated mild left papilledema,
with no alteration in her visual acuity or visual fields. She was admitted to the
hospital and anticoagulation was begun. Her headaches and contralateral PST
improved by the following day. Magnetic resonance brain imaging was performed
and MRA repeated, and these demonstrated no evidence of optic nerve or cerebral
edema, no venous infarction and early recanalization of the right dural sinus
outflow. She was discharged on hospital day #3 on an oral anticoagulant, with a
plan for continued anticoagulation for 4-6 months.
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