gms | German Medical Science

Objective: Large series of homogeneously managed intramedullary lesions are rare and frequently span many decades with different technological standards. As a centre for intramedullary tumour surgery we report on a series of 285 cases with intramedullary lesions and emerging concepts as well as open questions.

Methods: In the last 20 years 243 patients underwent 285 operations for intramedullary tumours. A retrospective neurological assessment according to the classification of Cooper and Epstein was performed to allow standardized comparison. Follow-up included examination of all patients pre- and postoperatively, after six months and one year and regular follow-up MRI.

Results: For analysis, the lesions were grouped by location: group 1 (N=65): craniocervical and cervical, group 2 (N=189): cervicothoracic, group 3 (N=31) thoracolumbar, including conus. Histological classification of tumours followed the WHO criteria and combining all groups we found 200 patients with tumours. 83 lesions were considered vascular: cavernous hemangiomas (N=32) or hemangioblastomas (N=51), two lesions were non-tumorous intramedullary cysts. 42 tumours were referred after biopsy elsewhere. Of the tumorous lesions, 142 were completely resected and 58 underwent partial resection or only extended biopsy. The immediate and long-term neurological outcome was found to be associated with the preoperative status. Patients, who were diagnosed early and had only minor symptoms, usually complained of postoperative sensory deficits which resolved over two years on the average. Patients with Cooper and Epstein ≥3 were most prone to an aggravation of their symptoms. Persistent neurological deterioration occurred in 83 patients. The recurrency rate for tumours was nearly 8%. Adjuvant therapy was used in only 10 patients.

Conclusions: The prediction of histology from the neuroradiological appearance is difficult and therefore the resective option can only be assessed by exploration of the tumour. Standardized intraoperative management includes complete exposure by laminotomy, intraoperative ultrasound to verify the correct level before opening the dura, high-dose methylprednisolone, midline approach, CO₂ laser dissection in selected cases and electrophysiological monitoring. Early diagnosis is favourable for a better outcome. Because of poor vascularization and thus increased vulnerability, lesions in the middle thoracic region bear the highest risk for postoperative deterioration and permanent neurological impairment.