Vascular Management during Recurrent Skull Base Tumor Resection

Objective: Recurrent skull base tumor often involves important cerebral arteries and veins. It is a crucial aspect to evaluate cerebral artery collateral circulation and vein features before operation. Several means were adopted during recurrent skull base tumor resection, including ipsilateral bypass, bilateral bypass, direct suture and emergency artery interposition bypass, and vein repair. Appropriate vascular management is the key point for total resection and decrease vascular complications.

Means: A total of 46 cases recurrent skull base tumor resection, which need vascular management before or during operation, were retrospectively analyzed from January 2013 to December 2017. According to the operation results, all cases divided into four groups: (1) Ipsilateral ICA replacement (intraoperative bypass); (2) bilateral ICA replacement (before operation bilateral bypass); (3) vein repair during operation; (4) direct main artery suture or emergency artery interposition bypass. Vascular complications and total resection rate in postoperative MRI were adopted as evaluation indexes;

Results: Group 1: ipsilateral ICA replacement: ECA-RA-M2 bypass or STA-MCA bypass during operation: 13 cases; total resection rate 84.6% (11/13); vascular complications 2 cases (postoperative infarction). Group 2: bilateral ICA replacement (ECA-RA-M2/contralateral: STA-MCA double bypass with 3-month interval) before operation: 6 cases. All six cases are recurrent nasopharyngeal carcinoma after radiation therapy. Total resection (in MRI) rate: 83.3% (5/6); no vascular-related complications. Group 3: vein repair during operation: 9 cases, including vein interposition bypass: 2 cases; sigmoid sinus reanastomosis: 4 cases; vein direct suture: 3 cases. Total resection rate = 100%; no vascular complications. Group 4: Direct main artery suture or interposition bypass:18 cases; including ICA direct suture 5 cases; emergency artery interposition bypass 4 cases; M1 or M2 direct suture 6 cases; PICA direct suture 3 cases; all 14 cases of direct suture cases have no vascular complications; artery interposition bypass: 2/4 have postoperative MRI infarction; all 18 cases achieved total resection.

Conclusion: It is very important to evaluate vascular involvement before recurrent skull base tumor operation. Bypass before or during operation takes more risk than direct suture for postoperative infarction. Tumor removal should be very careful to decrease the rate of bypass, especially emergency artery interposition bypass. Vein management seems be safer than artery. Vascular complication rate is higher in emergency bypass group than in patients with chronic tumor involved artery stenosis (nasopharyngeal carcinoma after radiation therapy). Total resection rate will be greatly increased than that of no vascular management operation.