Surgery of intramedullary spinal cord tumors

The diagnosis and management of intramedullary spinal cord tumors have been significantly influenced by new diagnostic and surgical tools such as MRI, ultrasonic aspiration, intraoperative ultrasound, and evoked potential monitoring. In this study we compared the surgical results of our earlier cases using conventional methods with more recent cases using these new methods. We report our experience based on 44 adult cases. Histologic diagnosis revealed ependymoma (20 cases), astrocytoma (15 cases), glioblastoma multiforme (1 case), and other histologic diagnoses (8 cases). We performed 20 gross total resections, 19 partial resections, and 5 biopsies. The mean follow-up period was 25.8 months (3 months-10 years). Surgical results were improvement in 11 patients (25%), stabilization in 24 (54%), and deterioration in 9 (20%). The first 28 cases (group A) were diagnosed using conventional ventional myelography and CT myelography. The more recent 16 cases (group B) were diagnosed with MRI and operated on using techniques such as ultrasonic aspiration, intraoperative monitoring and ultrasound imaging. Radical surgery (total excison) was performed in 36% (n=10) of group A, while it was possible in 62% (n=10) of group B. Deterioration after operation was noted in 28% (n=8) of group A, but only 6.2% (n=1) of group B. These results stress the importance of a preoperative MRI scan and the positive effects of intraoperative ultrasound imaging, ultrasonic aspiration, and evoked potential monitoring on surgical results. With the help of these tools, most intramedullary spinal cord tumors may be diagnosed and treated surgically with significantly decreased risk. Radical surgery was possible in as many as 62% of our more recent patients. Partial resection with radiotherapy should be confined to patients with high-grade astrocytomas.     

脊髓髓内肿瘤的显微外科手术治疗

目的：探讨脊髓髓内肿瘤显微外科手术治疗的临床疗效。方法：回顾性研究经显微手术治疗的31全 髓髓内肿瘤,对肿瘤病理类型,临床症状、手术时机、手术切除技巧及常见肿瘤的手术方法进行系统分析。结果：全切除肿瘤29例、2例星形细胞瘤次全切,我手术死亡及手术致残者,术后神经系统功能多数得以恢复或改善。结论：显微手术是脊髓髓内肿瘤最有效的治疗方法,用微创性手术技术早期切除肿瘤可获得满意疗效。     

Functional outcome after surgical treatment of intramedullary spinal cord tumors: experience with 78 patients

OBJECTIVE: To analyze factors with impact on the functional outcome for patients with surgically treated intramedullary spinal cord tumors (IMSCT) and to point out characteristics of the different histological entities. SETTING: Neurosurgical Department, University of Essen, Germany. METHODS: Between 1990 and 2000, a consecutive series of 78 patients were referred to our institution and underwent surgical treatment. There were 46 (59%) male and 32 (41%) female patients. Mean age was 43.3 years. Functional outcome was analyzed depending on histological features, age, tumor localization and the extension of involved spinal segments. The mean follow-up period was 34.4 months. Operative removal of the IMSCT was performed under standard microsurgical conditions with intraoperative monitoring of somatosensory-evoked potentials (SSEP). RESULTS: The most frequently involved localization was the cervical and cervicothoracic region (55%) followed by the thoracic region (32%) and the medullar conus (13%). The most frequent IMSCTs were neuroepithelial tumors in 44 patients (56.5%) including 32 patients with ependymomas, 15 astrocytomas, and two lesions without further histological classification. Non-neuroepithelial tumors included 10 metastases, nine cavernomas, eight hemangioblastomas, one dermoidal cyst and one enterogenetic cyst. Complete tumor removal was achieved in 65 cases (83.3%) and subtotal resection in nine cases. In four cases a biopsy was performed only. The overall postoperative neurological state was improved or unchanged in 51 patients (65.4%) and worsened in 27 patients (34.6%). A favorable functional outcome was observed in 94.1% of patients with vascular tumors, in 61.3% of patients with low-grade neuroepithelial tumors and in 53.3% of patients with malignant tumors. CONCLUSIONS: The strongest predicting factor of functional outcome was the preoperative neurological condition beyond the histological differentiation of the IMSCT. Although there was no outcome difference with respect to the age and tumor extension, thoracically located IMSCTs proved to harbor an increased risk of postoperative surgical morbidity.     

脊髓髓内肿瘤的显微外科治疗(附31例临床报告)

目的:报告31例脊髓髓内肿瘤的显微外科治疗结果,总结髓内肿瘤的显微外科治疗经验。方法:回顾性分析31例脊髓髓内肿瘤的临床表现、影像学特征、手术方法、手术技巧、手术结果,讨论手术时机的选择、术中注意事项及围手术期处理。结果:31例病人中星形细胞瘤12例,室管膜瘤10例,海绵状血管瘤6例,脂肪瘤1例,神经纤维瘤1例,室管膜囊肿1例。显微手术下肿瘤全部切除26例（84％）,次全切除3例（10％）,部分切除2例（6％）。术后死亡1例。随访19例,症状改善13例,不变3例,加重3例。结论:显微手术切除是髓内肿瘤唯一有效的治疗手段。强调室管膜瘤应全切除,星形细胞瘤追求全切除并尽量保持脊髓功能,脂肪瘤也可做到全切。     

Surgical treatment of intramedullary spinal cord tumors: prognosis and complications

STUDY DESIGN: Retrospective case series. OBJECTIVE: To evaluate our recent treatment strategy for intramedullary spinal cord tumors. SETTING: Department of Orthopaedic Surgery, Keio University, Japan. METHODS: We reviewed 68 cases of intramedullary tumors (ependymoma, 33; astrocytoma, 23; hemangioblastoma, 12), treated surgically between 1994 and 2003. There were 42 males and 26 females whose mean age at the time of surgery was 43 years. The mean follow-up period was 6.2 years. The tumor malignancy grade according to the WHO classification was astrocytoma grade I, 3; grade II, 8 (low-grade: 11 cases); grade III, 10; grade IV, 2 (high-grade: 12 cases). All ependymomas were grade II. Three of the 12 hemangioblastomas were associated with von Hippel-Lindau disease. RESULTS: Total excision was achieved in 90% of the ependymomas and functional improvement was obtained when the preoperative neurological deficit was mild. Approximately 50% of low-grade astrocytomas could be totally excised with favorable survival outcomes, suggesting that total excision should be attempted for low-grade astrocytomas. However, total excision of high-grade tumors was difficult and the functional outcomes were poor. Cordotomy should be considered in patients with a thoracic high-grade astrocytoma. Total resection was possible in 92% of hemangioblastoma, and the functional outcomes were good, however, more attention should be paid for tumors with feeding arteries on the ventral side and for those associated with von Hippel-Lindau disease. CONCLUSIONS: Predictors of good surgical outcome for intramedullary spinal cord tumors were histological grades of the tumors, surgical margins, and neurological status of the patient before surgery.     

CO2 laser surgery of intramedullary spinal cord tumors

Of a total of 580 patients suffering from expanding spinal disease, 15 cases of intramedullary lesions were dealt with by the use of the CO2 laser. Sharp cutting and precisely controlled depth effect are the advantages that make the CO2 laser very useful for surgery within the spinal cord. In tumors of tough consistency the neoplastic tissue is usually sharply demarcated, in which case the CO2 laser is used for dissection along this borderline, at an output energy of 15-20 W, infocus, continuous wave (CW). In tumors of soft consistency, characterized by a more-or-less diffuse zone of invasion--eg, glioblastomas-vaporization [20 W, out-of-focus, CW] and removal by ultrasound-microsuction is recommended. This procedure should advance layer by layer until normal looking tissue is reached. In this way intramedullary tumors may be removed with minimal side effects. The postoperative course involves less pain and less edematous reaction, and the rehabilitation time is shortened compared with conventional surgical treatment. In benign neoplasms long-term results are good; malignant cases require additional x-ray treatment and chemotherapy.     

脊髓髓内肿瘤的显微外科治疗及临床观察

目的　总结脊髓髓内肿瘤的显微手术经验 ,并对其并发症的处理及疗效进行评价。方法　对 48例髓内肿瘤采用显微外科手术。术中取侧卧位或半坐位 ,正中切口 ,尽量做到全切 ,并观察其术后的并发症及处理。结果　本组室管膜瘤、星形细胞瘤、脂肪瘤和血管网状细胞瘤分别占髓内肿瘤的 3 7.5 %、2 9.2 %、2 0 .8%、10 .4% ,其全切率分别为 88.9%、2 8.6%、10 .0 %、60 .0 % ;1例转移瘤全切。术后早期有感觉缺失 ,主要并发症有感染。 48例全部随访 ,平均 3 0 .4个月 ,大部分病人术后 1～ 3个月功能好转或无继续恶化 ,47例存活 ,1例死亡。结论　脊髓髓内肿瘤以良性及低恶性度肿瘤多见 ,手术效果较好 ,应尽早手术     

延颈髓肿瘤12例显微外科治疗

目的：探讨不同病理类型的延颈髓肿瘤临床特征和影像学诊断，及手术时机和技巧。方法：回顾性分析12例延颈髓肿瘤的病理类型、临床表现、辅助检查、手术切除程度及临床疗效。结果：12例延颈髓肿瘤中全切除11例，占91．67％，1例纤维坏死组织近全切除，无手术死亡率，全组病例临床表现均得到改善。结论：延颈髓肿瘤可通过MRI检查作出正确诊断，对绝大多数肿瘤可通过显微外科手术切除，对恶性肿瘤应辅以放射治疗。     

Radical resection of intramedullary spinal cord tumors in adults. Recent experience in 29 patients

The management of patients with intramedullary spinal cord tumors is controversial. In the past, these tumors have often been treated with biopsy or subtotal removal followed by irradiation--a therapy that is usually associated with early tumor recurrence and progressive neurological impairment. In an attempt to improve on the outcome of patients with intramedullary tumors, the authors performed radical resection in most of the 29 adult patients who had surgery for these tumors within the past 30 months. The mean duration of symptoms was 9 1/2 years, and all patients presented because of progressive neurological deficit. Patients were evaluated with metrizamide myelography-computerized tomography scanning and intraoperative ultrasound imaging to define the site of the tumor and cystic components. There were 14 ependymomas, 11 astrocytomas, two lipomas, and one case each of intramedullary fibrosis and astrogliosis. Solid tumor spanned a mean of five spinal cord segments and 16 tumors were associated with cysts. Twenty tumors were in the cervical and/or cervicothoracic regions. Total removal was achieved in 14 patients and "99% removal" in seven others. In 21 of 29 patients (72%), the neurological condition was stabilized or improved as a result of the operation. Postoperative deterioration occurred for the most part in patients who could not walk or who had minimal motor function at the time of operation, and these patients are no longer considered as operative candidates. Radical resection of intramedullary tumors can be achieved, with stabilization or improvement of neurological deficit in the majority of patients.