The Analysis Of Correlation Factors For The Microsurgical Treatment Effect Of The Foramen Magnum Tumors

Objective: To analyze the radiologic and clinical features with the foramen magnumtumors, retrospectively; exploring the correlation factors about the diagnosis,treatment and prognosis of it.Materials and Methods: We collected53cases of foramen magnum tumorsdiagnosed and operated between January2006and May2012in the neurosurgerydepartment in Tongji Hospital, affilicating to Huazhong University of Science andTechnology, which Included clinical features, radiologic materials, operation methods,pathological outcomes, complications and management, Follow-up and prognosis.Analyzing and discussing the correlation factors about diagnosis, treatment andprognosis of the foramen magnum tumors.Results: For53cases, total resection was achieved in45patients and subtotalresection was achieved in8patients, and gross total resection rates reaches84.9%（45/53）; The clinical conditions improved significantly for47patients, worsened for4patients, and did not change for2patients; follow-up was obtained in50cases,44cases had a normal life (KPS of80~100),6patients had a disability life (KPS, below80), including4cases of death.(一)Far-lateral approach was performed in15anteriorand lateral foramen magnum tumors, standard posterior midline approach in38posterior cases, the rates of complete removal between the two approaches were66.7%(10/15) and92.1%（35/38）respectively, P>0.05, no statistic difference betweenthem.(二) The gross total resection rates was93.1%（41/44）for the intradural tumors,but only37.5%（3/8）for intraextradural. P<0.05and significant differences in place.(三) The rates of complete removal were respectively44.4%（4/9）and93.1%(41/44)between the tumors encasing VA and no encasing. P<0.05and significant differencesin place. There was no iatrogenic injury with vascular and nerve in16cases by electrophysiological monitoring.Conclution:1. The effect of microsurgical operation for foramen magnum tumors is good;anappropriate surgical approach and technique is very important for the removingcompletely and safely with the tumor;2. Electrophysiological monitoring during the operation and the management forpostoperative complications in time is very important for the prognosis;3It is very difficult and risky to resect completely the intraextradural tumor/thetumors encasing VA/recurrence tumors,In preoperatively,we should analyze the radiologicmaterials carefully.