Cerebral Venous Sinus Thrombosis After Translabyrinthine Vestibular Schwannoma—A Prospective Study and Suggested Management Paradigm

Abstract

Objective: To prospectively evaluate the incidence, risk factors and natural history of postoperative cerebral venous sinus thrombosis (pCVST) in translabyrinthine vestibular schwannoma microsurgical resection and propose a potential management paradigm. Study Design: Prospective, single cohort, multicenter study. Setting: State-wide academic tertiary referral centers. Patients: Fifty-four consecutive patients who underwent translabyrinthine vestibular schwannoma resection. Main Outcome Measures: Incidence of pCVST on postoperative imaging on Day 7, Day 28, and 12 months postoperatively. Patients and tumor characteristics, risk factors, length of stay, intraoperative parameters, complications, and follow-up were analyzed. Results: pCVST was demonstrated in 21 patients (38.9%) on postoperative imaging. All patients with pCVST were treated conservatively and remained asymptomatic in the immediate postoperative period and long-term follow-up. There were no instances of venous infarction, intracranial hemorrhage, or neurological deficits. A majority (61.1%) of pCVST recannalised on long-term follow up with conservative management. There was a statistical association with pCVST and surgery on the side of the non-dominant cerebral venous drainage (n = 17, 80.1%, p = 0.034). Patients with pCVST were significantly more likely to have a postoperative cerebrospinal fluid (CSF) leak (n = 5, 23.8%, p = 0.017). Conclusion: The incidence of pCVST following translabyrinthine vestibular schwannoma resection is much higher than previously recognized. pCVST is more likely to occur when surgery is performed on tumors situated on the side of non-dominant cerebral venous drainage. Despite the high prevalence of this iatrogenic phenomenon, all patients were asymptomatic and a majority resolved, thereby suggesting that conservative management is safe. Correlation between pCVST and increased incidence of CSF leak requires further investigation.

Dural sinus thrombosis after resection of vestibular schwannoma using suboccipital retrosigmoid approach—thrombosis classification and management proposal

“…Some cases of fatal course of sinus thrombosis have even been presented [9]. However, most studies emphasize mild or even asymptomatic course of lateral sinus thrombosis [1,2,3,5,8]. In our study, most of the patients, except one, were completely asymptomatic.…”

“…The main concern in dural sinus thrombosis is prevention of the thrombus propagation, obstruction of the blood drainage and increased intracranial pressure due to hyperemia or intracerebral hemorrhage. Such a situation could be fatal, as reported [5]. The role of anticoagulation is to prevent such thrombus progression.…”

“…It provides wide exposure of the cerebellopontine angle and gives an opportunity to resect large tumors and preserve hearing in some cases. Lateral sinus thrombosis is a known complication after the posterior fossa surgery and has been noted in 4.7-11.6% of cases [2][3][4][5][6][7][8]. However, there is limited data about that complication exclusively in the vestibular schwannoma surgery.…”

“…There is a series of studies [1,4,10], however, they have some limitations. In most of them non-contrast CT was used as a postoperative control [1], the analyzed cohort included various surgical approaches [1,3,10] or translabyrinthine approach [5]. There are no large cohort studies with well-documented postoperative radiological investigation on the retrosigmoid approach in the vestibular schwannoma surgery.…”

“…Dural sinus thrombosis (DST) it is a complication after posterior fossa surgery, especially in the cases of vestibular schwannoma surgery and is reported in 4.7-38.9% [1][2][3]5]. Various intraoperative risk factors, which could cause such complication have been described: injury of the dural sinus, long duration of the surgery, surgical mobilization of the sinus, bone skeletonization around the sinus, thermal injury caused by coagulation, or even heat generated by a microscope lamp [1].…”