Dural venous sinus thrombosis after cerebellopontine angle surgery: Should it be treated?

INTRODUCTION: Dural venous sinus thrombosis is an uncommon, but significant sequela that may occur after resection of a cerebellopontine angle lesion. The natural history and management of this pathology has not been sufficiently studied.
METHODS: All operative cases for cerebellopontine angle lesions performed in our local institution dating from 1 January 2005 to 30 June 2018 were retrospectively reviewed to identify patients who developed new post-operative dural venous sinus thrombosis. Patients who developed a significantly narrowed sinus without intrinsic thrombus were also identified. Progression of sinus thrombosis through time was followed, with comparisons made between complications amongst patients with and without a compromised sinus.
RESULTS: Of the 126 patients, 20 were found to have new sinus thrombosis, with another 16 developing a critically narrowed sinus without intrinsic thrombus. These cases are significantly associated with translabyrinthine resection of acoustic schwannoma. 4 patients amongst the thrombosed group were commenced on additional therapeutic anticoagulation or antiplatelets, whilst the rest were observed. Based on available follow up imaging, 10/17 patients had significantly improved sinus thrombosis on serial imaging, including 8/14 amongst those not given additional anticoagulation. Patients with a compromised sinus demonstrated a higher rate of cerebrospinal fluid leak requiring blindsac procedures. When involving a dominant sinus, there is also an association of an increased requirement for permanent CSF diversion.
CONCLUSION: Therapeutic anticoagulation should be considered for symptomatic post-operative dural venous sinus thrombosis or if it involves a dominant sinus. Further prospective studies are warranted to better elucidate the risk-benefit justification of treatment for postoperative sinus thrombosis.