Surgical results of intramedullary spinal cord tumor with spinal cord monitoring to guide extent of resection.
OBJECTIVE
The authors investigated the outcome of intramedullary spinal cord tumor surgery, focusing on the effect of preoperative neurological status on postoperative mobility and the extent of tumor excision guided by intraoperative spinal cord monitoring prospectively.


METHODS
Intramedullary spinal cord tumor surgery was performed in 131 patients between 1997 and 2007. The authors compared the pre- and postoperative neurological status and examined the type of surgery in 106 of these patients. A modified McCormick Scale (Grades I-V) was used to assess ambulatory ability (I = normal ambulation; II = mild motor sensory deficit, independent without external aid; III = independent with external aid; IV = care required; and V = wheelchair required). The type of surgery was classified into 4 levels: total resection, subtotal resection, partial resection, and biopsy.


RESULTS
The 106 patients consisted of 47 females and 59 males, whose average age was 42.5 years (range 6-75 years). The mean follow-up period was 7.3 years (range 2.5 months-21 years). The tumor types included astrocytoma (12 cases), ependymoma (46 cases), hemangioblastoma (16 cases), cavernous hemangioma (17 cases), and others (15 cases overall: gangliocytoma, 1; germ cell tumor, 1; lymphoma, 3; neurinoma, 1; meningioma, 1; oligodendroglioma, 1; sarcoidosis, 2; glioma, 1; and unknown, 4). Initial total excision, subtotal resection, partial resection, biopsy, and duraplasty were performed in 59, 12, 22, 12, and 1 patients, respectively. According to the preoperative McCormick Scale, ambulatory status was classified as Grades I, II, III, IV, and V in 41(38%), 30 (28%), 14 (13%), 19 (19%), and 2 (2%) patients, respectively. Thirty-three (31%) of 106 patients suffered postoperative neurological deterioration. The number of patients who did not lose ambulatory ability or who achieved an ambulatory status of Grade I or II postoperatively was 33 (80%), 21 (70%), 10 (71%), 8 (42%), and 1 (50%) in patients with preoperative Grades I, II, III, IV, and V, respectively. Total excision was performed in 31 (79%) of 39 patients with preoperative Grade I, 12 (40%) of 30 patients with Grade II, 7 (50%) of 14 patients with Grade III, and 9 of 21 patients (38%) with Grade IV or V, indicating that the rate of total excision was significantly higher in patients with Grade I status.


CONCLUSIONS
The postoperative ambulatory ability was excellent in patients with a good preoperative neurological status. Total excision in patients with Grade I or II ambulation was associated with a good prognosis for postoperative mobility. However, the rate of postoperative deterioration was 31.5%, which is relatively high, and patients should be fully informed of this concern prior to intramedullary spinal cord tumor surgery.
Department of Orthopaedic Surgery, Nagoya University School of Medicine, Nagoya, Aichi, Japan. spine-yu@med.nagoya-u.ac.jp
Yukihiro
Y
Matsuyama
Yoshihito
Y
Sakai
Yoshito
Y
Katayama
Shiro
S
Imagama
Zenya
Z
Ito
Norimitsu
N
Wakao
Koji
K
Sato
Mitsuhiro
M
Kamiya
Yasutsugu
Y
Yukawa
Tokumi
T
Kanemura
Makoto
M
Yanase
Naoki
N
Ishiguro
D000293:Adolescent; D000328:Adult; D000368:Aged; D001254:Astrocytoma / Q000601:surgery; D002648:Child; D004806:Ependymoma / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D018325:Hemangioblastoma / Q000601:surgery; D006392:Hemangioma, Cavernous / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D019635:Neurosurgical Procedures / Q000379:methods*; D011183:Postoperative Complications; D011379:Prognosis; D011446:Prospective Studies; D013120:Spinal Cord Neoplasms / Q000601:surgery*; D016138:Walking