Analysis Of A Series Of Cases Of Neuroendoscope-assisted Resection Of Posterior Fossa Tumors

Objective: To explore the application value of neuroendoscopic-assisted resection of posterior fossa tumors,and to evaluate the feasibility and safety of this technique again.Methods: A total of 14 patients with posterior cranial fossa tumors who were hospitalized in the Department of Neurosurgery of Guizhou people’s Hospital from July2019 to June 2021 were selected,including 7 males and 7 females,aged from 2 to 69 years(37.3 ± 21.5)years.The course of disease was 27 days(7-160)days;the main clinical symptoms were limb fatigue,dysphagia,headache,dizziness,blurred vision,ataxia and sudden disturbance of consciousness.The tumor volume was 7-49cm3(21 ± 13)cm3.Individualized design of surgical approach,strict grasp of endoscopic keyhole approach surgical indications,selective or emergency surgical treatment.The tumors were mainly located in brain stem,fourth ventricle,cerebellar hemisphere,tentorium,pineal region,petrosal apex,flat skull base in 1 case,ossification and flexion difficulty of posterior longitudinal ligament in 1 case,solid tumor in 12 cases,cystic tumor in 2 cases,compression of fourth ventricle in 5 cases,compression or occlusion of brainstem and peri-midbrain cistern in 1 case,and obvious supratentorial water in 3 cases.If the main body of the tumor is located in the midline,the prone position is taken.According to the specific location and size of the tumor,the retrosigmoid sinus,para-median approach,median approach and transtentorial cerebellar approach are used during the operation.The same operation was performed by the German STORZ neuroendoscope system,and the tumor was removed strictly according to the principle of microscope operation under neuroendoscope.According to the need for axial rotation,so as to achieve the purpose of multi-angle observation,to determine whether there is tumor residue and whether to damage normal nerves and vessels.The amount of intraoperative blood loss,operation time,postoperative hospital stay and postoperative complications were analyzed to evaluate the surgical effect.Glasgow outcome scale(GOS)was performed to evaluate the prognosis at discharge.And the patients were followed up for 6 months,including tumor recurrence,quality of life assessment and Activities of daily living(ADL)score.Results: 1.Postoperative pathological findings suggested cavernous angioma in 3patients,medulloblastoma in 1 patient,ependymoma in 1 patient,dysplastic gangliocytoma of cerebellum in 2 patients,mixed germ cell tumor meningioma in 1 patient,cerebellar metastases in 3 patients,meningioma in 2 patients,and astrocytoma in 1 patient.2.GOS score 4(3-4)points at discharge,operative time: 75-280(163±59)minutes,hospital stay:7-40(20±9)days,13 with total resection and 1 with subtotal resection;The incidence of postoperative complications was 29%.3.Among 12 cases of elective operation,1 case was discharged from hospital because of aggravation of progressive consciousness of cerebral infarction,and 1 patient with brain metastasis of small cell lung cancer died after follow-up for 6 months.2 cases of emergency operation: 1 case of brainstem cavernous hemangioma gave up treatment 24 days after operation and died after follow-up.Three patients died in June of follow-up,the remaining patients were matched with respect to ADL scores at discharge,which were 75(60-100)points at discharge and 70(70-100)points at 6 months after surgery(P > 0.05),while no significant differences were observed between ADL scores at discharge and those at 6 months after surgery.Conclusion: Subtentorial neuroendoscopic treatment of posterior fossa tumors is safe and effective,and can be used as an effective way to remove posterior fossa tumors,especially in children or patients with posterior skull base depression,cyclo-occipital fusion,atlantoaxial dislocation and ossification of posterior longitudinal ligament in the elderly.The feasibility of transcranial neuroendoscopic surgery should be evaluated individually before operation.During neuroendoscopic craniotomy,we should give full play to the advantage of neuroendoscopic close magnification,make use of physiological space and fistulostomy to achieve tumor exposure and resection by the shortest path,so as to avoid the disadvantage of exposing more brain tissue under microscope.The intraoperative use of neuroendoscope to give full play to the advantages of endoscopic multi-angle,improve visualization,improve tumor resection rate,keyhole craniotomy to reduce surgical trauma and postoperative discomfort.