Microsurgical Excision of Intramedullary Spinal Cord Tumors: Surgical Strategy and Clinical Outcome

Background: Intramedullary spinal cord tumors (IMSCT) represent only 2-4% of allcentral nervous system tumors, and due to the fragile nature of the spinal cord, totalexcision with minimal tissue injury remained a great challenge for neurosurgeons.Objectives: To evaluate the feasibility of neurophysiologically monitored microsurgicalstrategy for gross total excision of IMSCT and its impact on clinical outcome, diseaseprognosis and the need for adjuvant therapy. Patients and Methods: The currentprospective study was conducted on fourteen patients with median age of 9.5 yearshaving IMSCT treated in Cairo University hospitals and Children s Cancer HospitalEgypt (CCHE) from August 2010 to April 2013. According to Modified McCormickclassification; three patients (21.4%) clinically presented with G I, seven patients (50%)with G II, three patients (21.4%) were G III while one patient (7.1%) was G IV. Allpatients were operated upon under guidance of intraoperative neurophysiologicalmonitoring (IONM) aiming at gross total excision except one case of cervicodorsal GIIastrocytoma was unresectable and just biopsied. Clinical and radiological follow upwere performed throughout follow up period ranging from 12-24 months. Results:Gross total excision was achieved in ten cases (71.4%), subtotal resection in three cases(21.4%) and tissue biopsy in one case (7.1%). Tumors were ten ependymomas (71.4%)and four astrocytomas (28.6%). Clinical improvement was achieved in four patients(30.8%) within the 1st postoperative week and in seven patients (53.8%) at 12 monthsfollow up, postoperative neurological deterioration was noted in two patients (15.4%)without significant improvement throughout follow up. None of the ten patients havinggross total tumor resection needed adjuvant therapy, while the remaining four caseswere candidates for radiotherapy and/or chemotherapy (one of these four patients hadtumor recurrence 6 months following subtotal resection). Postoperative CSF leak wasencountered in three cases (21.4%) and conservatively ended except one of them neededsurgical dural repair. Two patients (14.3%) had postoperative wound infection whichresolved in 7-9 days of antibiotic therapy. Conclusion: The primary goal of managementof intramedullary spinal cord tumors should be aiming microsurgical gross totalresection with wide myelotomy, minimal use of coagulation in addition to intraoperativemonitoring (motor evoked potential (MEP) mainly) -which seems to be a crucial factoraffecting the clinical outcome- achieving reasonable degree of neurologicalimprovement (70%), better prognosis and decreasing the need for adjuvant therapy