Surgical management of ventrally located spinal meningiomas via posterior approach

Resection vs. coagulation of dural attachment in patients with spinal meningioma: an updated systematic review and meta-analysis

BACKGROUND

The Simpson grading scale assumes dural resection (grade I) is more effective against recurrence than coagulation (grade II). However, the results of recent studies have raised doubts about this effectiveness in spinal meningiomas. Therefore, we aimed to perform a meta-analysis comparing outcomes between Simpson grades I and II in spinal meningiomas.

METHODS

According to the PRISMA statement, we systematically searched PubMed, EMBASE, and Web of Science for studies involving patients with spinal meningiomas who underwent Simpson grades I, II, III, or IV. Outcomes were radiological tumor recurrence, postoperative neurological deficits, and procedure-related complications.

RESULTS

We included 54 studies with a total of 3334 patients. Simpson grades I, II, III, and IV were performed in 674 (20%), 2205 (66%), 254 (8%), and 201 (6%) patients, respectively. The follow-up ranged from 9 to 192 months, and 95.4% of all tumors were WHO grade 1. There was no difference in radiological tumor recurrence (OR 0.80, 95% CI: 0.46-1.36, P = 0.41; I2 = 0%), postoperative neurological deficits (OR 0.74, 95% CI: 0.32-1.75, P = 0.50; I2 = 0%) or procedure-related complications (OR 2.22, 95% CI: 0.80-6.13, P = 0.12; I2 = 3%) between Simpson grades I and II. Furthermore, no significant difference in postoperative neurological deficits or procedure-related complications was detected when comparing all Simpson's to each other. However, radiological tumor recurrences in Simpson I and II were significantly lower than in III and IV, with Simpson III outperforming IV (OR 0.19, 95% CI: 0.09-0.40, P < 0.01; I2 = 0%).

CONCLUSION

Simpson grade I is not more effective than grade II in any outcome, although both are superior to III and IV in tumor recurrence. Our results might suggest that dural coagulation is preferable over resection when the latter carries a higher risk of complications.

Indications for Fusion With Intradural Spine Tumor Resection in Adults: A Systematic Review and Meta-analysis

BACKGROUND

The evidence for instrumented fusion in the setting of degenerative, traumatic, or congenital deformity is well established. Data on fusion indications in intradural spinal tumors (IDST) are scarce and reduced to retrospective studies. The objective of this work is to systematically review the published literature since 2015 and analyze the change of practice patterns for stabilization and fusion after intradural tumor resection in adults.

METHODS

A systematic literature review was performed via PubMed with the terms: "intradural spinal tumors", "intramedullary spinal tumors", and "intraspinal tumors". The analysis was limited to adult patients with IDST and studies with more than 10 patients. Data on the proportion of patients who underwent instrumentation and had postoperative deformity was pooled in a meta-analysis.

RESULTS

A total of 1073 articles were identified and 47 papers were selected. All the studies were retrospective series and a total of 2473 patients were included. The follow-up ranged from 1 to 96 months, the pooled spinal fixation rate was 6% (95% CI 4.5%-7.6%), the pooled laminoplasty rate was 14.4% (95% CI 5.9%-23%), the pooled rate of postoperative deformity or malalignment in patients with a follow up of at least 6 months was 2.1% (95% CI 1.2%-3%) and just 7 patients were reoperated due to progressive deformity.

CONCLUSIONS

Based on existing evidence, the rate of fusion during resection of intradural spinal tumors is low. Prophylactic fixation is often unnecessary and only indicated in unique cases that require extensive bony resection.

Current Knowledge on Spinal Meningiomas-Surgical Treatment, Complications, and Outcomes: A Systematic Review and Meta-Analysis (Part 2)

Background: Most of the knowledge on spinal meningiomas is extrapolated from their intracranial counterparts, even though they are considered separate entities. This review aimed to systematically summarize studies covering different aspects of spinal meningiomas and their management. Methods: Databases were searched for all studies concerning spinal meningiomas dating from 2000 and onwards. When possible, a meta-analysis was performed. Results: Neurological outcomes of surgery were consistently favorable across studies, with a complication rate of 7.9% and 78.9% of the patients demonstrating good postoperative neurological function (McCormick score 1−2). The most relevant predictors of unfavorable outcomes were poor preoperative status, longer time from diagnosis to surgery, and surgery of recurrent tumors. The recurrence rate after surgery was estimated at 6%. Meta-analysis and/or survival analysis revealed that higher WHO grade (p < 0.001), higher Simpson grade (p < 0.001), ventral tumor location (p = 0.02), and male sex (p = 0.014) were all associated with higher odds of recurrence. However, the meta-analysis did not show any difference between Simpson grade 1 and grade 2 with respect to the odds of recurrence (p = 0.94). Surgery provided immediate and durable health-related quality-of-life improvement, as well as a high frequency of return to work. Conclusion: Spinal meningioma surgery is a relatively safe procedure with a low risk of tumor recurrence and high likelihood of favorable postoperative outcomes.

Long-term outcomes of spinal meningioma resection with outer layer of dura preservation technique

Spinal meningioma is a common benign intradural spinal tumor. It has been reported that the local recurrence rate after surgical resection increases with longer follow-up duration. Simpson grade 1 resection could reduce the risk of recurrence, but this procedure needs dural reconstruction, which would cause cerebrospinal fluid (CSF) leakage or iatrogenic spinal cord injury. Saito et al. reported dura preservation technique to reduce the risk of CSF leakage, in which the meningioma together with the inner layer of the dura is removed and the outer layer is preserved for simple dural closure. The long-term outcomes with this technique have never been investigated. In this study, we retrospectively analyzed the data of 38 surgically treated patients (dura preservation technique, 12 patients; Simpson grade 2 resection, 26 patients) to assess the long-term recurrence rate (mean, 121.5 months; range, 60-228 months). The local recurrence rate in the dura preservation group was 8.3% (1 of 12 cases), which was similar to that in Simpson grade 2 resection group (2 of 26 cases [7.7%]). Although this case series did not indicate the significant difference in the recurrence rates between the dura preservation group and Simpson grade 2 group, we consider that this technique still has advantages for surgically less invasiveness in terms of dural reconstruction which is necessary for Simpson grade 1 and higher possibility of complete resection of tumors compared with Simpson grade 2 resection.

Low recurrence after Simpson grade II resection of spinal benign meningiomas in a single-institute 10-year retrospective study

The objective of this study was to more fully understand the optimal neurosurgical strategy for spinal benign meningiomas from a medium to long-term perspective. This retrospective study included a cohort of 35 patients with a diagnosis of spinal meningioma who were first operated at our institute over the past 10 years and followed-up for at least 2 years after surgery. The inclusion criterion for the study was the pathological diagnosis finally verified as benign meningioma of World Health Organization (WHO) grade 1. The average follow-up duration after surgery was 61.0 months. The location of the spinal meningioma was classified into ventral or dorsal type based on the operative video record and the preoperative MR images. The extent of resection of the spinal meningioma was carefully determined based on the Simpson grade. The average neurological condition was significantly improved at the final follow-up. Simpson grade I or II resection was achieved in 31 of 35 cases (88.6%). No Simpson grade I or II cases showed local recurrence during follow-up. Tumor recurrence was noted in 2 of 4 cases of Simpson grade IV resection. One case has been followed-up without any re-operation because of no neurological deterioration, and the other case underwent stereotactic radiosurgery. This study suggested that meticulous Simpson grade II resection of spinal benign meningiomas of WHO grade 1 may be good enough from a medium to long-term follow-up perspective, though longer follow-up is absolutely necessary.

Oncologic benefits of dural resection in spinal meningiomas: a meta-analysis of Simpson grades and recurrence rates

OBJECTIVE

While resection of the dural attachment has been shown by Simpson and others to reduce recurrence rates for intracranial meningiomas, the oncological benefit of dural resection for spinal meningiomas is less clear. The authors performed a systematic analysis of the literature, comparing recurrence rates for patients undergoing various Simpson grade resections of spinal meningiomas to better understand the role of dural resection on outcomes after resection of spinal meningiomas.

METHODS

The PubMed/Medline database was systematically searched to identify studies describing oncological and clinical outcomes after Simpson grade I, II, III, or IV resections of spinal meningiomas.

RESULTS

Thirty-two studies describing the outcomes of 896 patients were included in the analysis. Simpson grade I, grade II, and grade III/IV resections were performed in 27.5%, 64.6%, and 7.9% of cases, respectively. The risk of procedure-related complications (OR 4.75, 95% CI 1.27-17.8, p = 0.021) and new, unexpected postoperative neurological deficits (OR ∞, 95% CI NaN-∞, p = 0.009) were both significantly greater for patients undergoing Simpson grade I resections when compared with those undergoing Simpson grade II resections. Tumor recurrence was seen in 2.8%, 4.1%, and 39.4% of patients undergoing Simpson grade I, grade II, and grade III/IV resections over a mean radiographic follow-up period of 99.3 ± 46.4 months, 95.4 ± 57.1 months, and 82.4 ± 49.3 months, respectively. No significant difference was detected between the recurrence rates for Simpson grade I versus Simpson grade II resections (OR 1.43, 95% CI 0.61-3.39, p = 0.43). A meta-analysis of 7 studies directly comparing recurrence rates for Simpson grade I and II resections demonstrated a trend toward a decreased likelihood of recurrence after Simpson grade I resection when compared with Simpson grade II resection, although this trend did not reach statistical significance (OR 0.56, 95% CI 0.23-1.36, p = 0.20).

CONCLUSIONS

The results of this analysis suggest with a low level of confidence that the rates of complications and new, unexpected neurological deficits after Simpson grade I resection of spinal meningiomas are greater than those seen with Simpson grade II resections, and that the recurrence rates for Simpson grade I and grade II resections are equivalent, although additional, long-term studies are needed before reliable conclusions may be drawn.

Microsurgical Management of Ventral Intradural-Extramedullary Cervical Meningiomas: Technical Considerations and Outcomes

OBJECTIVE

Cervical meningiomas are uncommon intradural-extramedullary tumors that have a tendency to be situated anterior to the spinal cord. The optimal surgical corridor to reach purely ventral cervical meningiomas has not been established. This article presents a series of patients with ventral cervical meningiomas treated via 1 of 2 microneurosurgical approaches: the anterior approach with corpectomy and fusion or the posterolateral approach.

METHODS

Eight patients who underwent surgical resection of solitary, histopathologically confirmed, intradural-extramedullary cervical meningiomas of purely ventral location were retrospectively examined. Preoperative and postoperative Nurick scores quantified the degree of ambulatory function. Patients were followed for an average of 2.1 years after surgery. Postoperative imaging was performed to determine the extent of resection and to assess for tumor recurrence.

RESULTS

Two patients with lower cervical meningiomas underwent resection via an anterior approach with single-level corpectomy and fusion. Six patients were treated via a posterolateral approach including ipsilateral hemilaminectomy and partial facetectomy without fusion. No intraoperative or postoperative complications were observed. Gross total resection was achieved in 8 of 8 patients, although 1 patient exhibited tumor recurrence. Improvement in ambulatory function was observed in all patients.

CONCLUSIONS

Purely ventral cervical meningiomas are uncommon and pose unique technical challenges for neurosurgeons. We document favorable outcomes from 2 cases of lower cervical meningioma treated via an anterior approach and 6 cases of upper cervical tumors treated via a posterolateral approach. This series demonstrates operative considerations for effectively managing ventral cervical meningiomas.

[Application of posterior approach for atlantoaxial subdural extramedullary nerve sheath tumors]

OBJECTIVE

To investigate the procedure and effectiveness of posterior approach for operation of atlantoaxial subdural extramedullary nerve sheath tumors.

METHODS

Between January 2012 and March 2017, 9 patients with atlantoaxial subdural extramedullary nerve sheath tumors were treated, including 7 males and 2 females, aged 25-62 years (mean, 45.4 years). There were 8 cases of neurinoma and 1 case of neurofibroma. The tumors were located at C1 in 1 case and C1, 2 in 8 cases. The disease duration ranged from 5 to 120 months, with an average of 45.9 months. The neural function was rated as grade D in 8 cases and grade E in 1 case according to the American Spinal Injury Association (ASIA) grading system. The Japanese Orthopaedic Association (JOA) score was 12.8±2.5. All patients underwent posterior cervical surgery. The laminae were replanted and fixed in 2 cases. The atlantoaxial or occipitocervical axis was not fixed in all patients.

RESULTS

The operation time was 90-343 minutes, with an average of 179.2 minutes. The intraoperative blood loss was 50-1 000 mL, with an average of 335.6 mL. No relevant complication occurred after operation. All patients were followed up 6-21 months (mean, 11.1 months). The postoperative X-ray films showed the good stability of the cervical spine. All patients had complete tumor resection and no recurrence. The replanted laminae achieved fusion and the internal fixation was firm. According to ASIA grading system, 3 patients of preoperative ASIA grade D had upgraded to grade E at 3 months after operation, while the remaining patients had no change in grading. The JOA score was 15.1±1.4 at 6 months after operation, which was significantly improved when compared with that before operation (t=4.221, P=0.003).

CONCLUSION

The atlantoaxial subdural extramedullary nerve sheath tumor (including the ventral tumor) can be removed completely via posterior approach. The axis lamina can be replanted and fixed with the small titanium plate or lamina screw when necessary, and the atlantoaxial or occipitocervical fixation was not needed.

Surgical management of spinal meningiomas: focus on unilateral posterior approach and anterior localization

OBJECTIVESpinal meningiomas (sMNGs) are relatively rare in comparison to intracranial MNGs. sMNGs localized anterior to the denticulate ligament (aMNGs) represent a surgically challenging subgroup. A high perioperative complication rate due to the need for complex surgical approaches has been described. In the present study, the authors report on their surgical experience that involves two institutions in which 207 patients underwent surgery for sMNGs. Special focus was placed on patients with aMNGs that were treated via a unilateral posterior approach (ULPA).METHODSBetween 2005 and 2017, 207 patients underwent resection of sMNGs at one of two institutions. The following characteristics were assessed: tumor size and localization, surgical approach, duration of surgery, grade of resection, peri- and postoperative complication rates, and neurological outcome. Data were compared between the subgroups of patients according to the lesion's relationship to the denticulate ligament and to surgical approach.RESULTSThe authors identified 48 patients with aMNGs, 86 patients with lateral MNGs, and 76 patients with posterior MNGs (pMNGs). Overall, 66.6% of aMNGs and 64% of pMNGs were reached via a ULPA. aMNGs that were approached via a ULPA showed reduced duration of surgery (131 vs 224 minutes, p < 0.0001) and had surgical complication rates and neurological outcomes comparable to those of lesions that were approached via a bilateral approach. No significant differences in complication rate, outcomes, and extent of resection were seen between aMNGs and pMNGs.CONCLUSIONSThe duration of surgery, extent of resection, and outcomes are comparable between aMNGs and pMNGs when removed via a ULPA. Thus, ULPA represents a safe route to achieve a gross-total resection, even in cases of aMNG.