Microsurgical treatment for parasagittal meningioma in the central gyrus region

Resection of meningiomas located in motor eloquent areas - comparative analysis of navigated transcranial magnetic stimulation and conventional neuronavigation

BACKGROUND

Navigated transcranial magnetic stimulation (nTMS) has been established as a preoperative diagnostic procedure in glioma surgery, increasing the extent of resection and preserving functional outcome. nTMS motor mapping for the resection of motor eloquent meningiomas has not been evaluated in a comparative analysis, yet.

METHODS

We conducted a retrospective matched-pair analysis for tumor location and size in meningioma patients with tumors located over or close to the primary motor cortex. Half of the study population received nTMS motor mapping preoperatively (nTMS-group). The primary endpoint were permanent surgery-related motor deficits. Additional factors associated with new motor deficits were evaluated apart from nTMS.

RESULTS

62 patients (mean age 62 ± 15.8 years) were evaluated. 31 patients received preoperative nTMS motor mapping. In this group, motor thresholds (rMT) corresponded with tumor location and preoperative motor status, but could not predict motor outcome. No patient with preoperative intact motor function had a surgery-related permanent deficit in the nTMS group whereas four patients in the non-TMS group with preoperative intact motor status harbored from permanent deficits. 13 patients (21.3%) had a permanent motor deficit postoperatively with no difference between the nTMS and the non-TMS-group. Worsening in motor function was associated with higher patient age (p = 0.01) and contact to the superior sagittal sinus (p = 0.027).

CONCLUSION

nTMSmotor mapping did not lead to postoperative preservation in motorfunction. nTMS data corresponded well with the preoperative motorstatus and were associated with postoperative permanent deficits if tumors were located over the motor hotspot according to nTMS.

Meningiomas of the rolandic region: risk factors for motor deficit and role of intra-operative monitoring

OBJECTIVE

Meningiomas of the rolandic region are associated to high risk of postoperative motor deficits. This study discusses the factors affecting motor outcome and recurrences from the analysis of a monoinstitutional case series and eight studies from a literature review.

METHODS

Data of 75 patients who underwent surgery for meningioma of the rolandic region were retrospectively reviewed. The analyzed factors included tumor location and size, clinical presentation, magnetic resonance imaging (MRI) and surgical findings, brain-tumor interface, extent of resection, postoperative outcome and recurrence. Eight studies from literature on rolandic meningiomas treated with or without intraoperative monitoring (IOM) were reviewed with the aim to define the impact of IOM on the extent of resection and motor outcome.

RESULTS

Among the 75 patients of the personal series, the meningioma was on the brain convexity in 34 (46%), at the parasagittal region in 28 (37%) and at the falx in 13 (17%). The brain-tumor interface was preserved in 53 cases (71%) at MRI and in 56 (75%) at surgical exploration. Simpson grade I resection was obtained in 43% of patients, grade II in 33%, grade III in 15% and grade IV in 9%. The motor function worsened postoperatively in 9 among 32 cases with preoperative deficit (28%) and in 5 among 43 with no preoperative deficit (11.5%); definitive motor deficit was evidenced in overall series at follow-up in 7 (9.3%). Patients with meningioma with lost arachnoid interface had significant higher rates of worsened postoperative motor deficit (p = 0.01) and seizures (p = 0.033). Recurrence occurred in 8 patients (11%). The analysis of the 8 reviewed studies (4 with and 4 without IOM) shows in the group without IOM higher rates of Simpson grades I and II resection (p = 0.02) and lower rates of grades IV resection (p = 0.002); no significant differences in postoperative immediate and long-term motor deficits were evidenced between the two groups.

CONCLUSIONS

Data from literature review show that the use of IOM does not affect the postoperative motor deficit Therefore, its role in rolandic meningiomas resection remains to be determined and will be defined in further studies.

Classification of Peritumoral Veins in Convexity and Parasagittal Meningiomas and Its Significance in Preventing Cerebral Venous Infarction

OBJECTIVE

The medium (2-4 cm) convexity located closer to the sinus and parasagittal meningiomas (Sindou type I-Ⅲ) without obvious invasion of the superior sagittal sinus are considered simple to operate on. However, the tumors are often accompanied by the cortical bridging vein. Because of lack of collateral vein circulation in cortical areas, the damage of peritumoral veins will subsequently lead to venous infarction. To avoid the serious complications caused by intraoperative injury of peritumoral veins, it is necessary to define the classification of the progression of peritumoral veins and tumors to guide surgical safety.

METHODS

The clinical information of 57 patients with convexity and parasagittal meningiomas was collected and retrospectively analyzed. All patients underwent preoperative magnetic resonance imaging and magnetic resonance venography scanning to observe the imaging characteristics of peritumoral veins and preoperative evaluation. The actual relationship between the tumor and peritumoral vein was observed intraoperatively. Postoperative computed tomography and magnetic resonance imaging were used to determine tumor resection and the presence of venous infarction.

RESULTS

According to preoperative magnetic resonance venography and intraoperative findings, we divided the peritumoral veins into 3 types: type A (n = 33, 57.9%), the vein surrounds the tumor; type B (n = 15, 26.3%), the vein is located on the ventral side of the tumor; and type C (n = 9, 15.8%), the vein is located on the dorsal side of the tumor. Peritumoral vein injury occurred in 6 cases followed by serious complications. Treatments were as follows: 4 cases underwent decompression and 2 cases were treated conservatively. The prognosis Glasgow Outcome Scale (GOS) scores were as follows: 3 cases were score 5 for injury of posterior frontal vein or middle frontal vein, 2 cases were score 3 for injury of the central vein, 1 case was score 1 for death due to injury of the central vein. All cases were followed up for 6 months.

CONCLUSIONS

Attention should be paid to the peritumoral vein of special meningiomas. Injured vein in the medial third of superior sagittal sinus carries a high rate of postoperative morbidity. Understanding the type of peritumoral veins preoperatively can be used as a guide in determining the corresponding protective strategy during surgery, which can significantly decrease postoperative disability and improve quality of life.

Surgical treatment of meningiomas located in the rolandic area: the role of navigated transcranial magnetic stimulation for preoperative planning, surgical strategy, and prediction of arachnoidal cleavage and motor outcome

OBJECTIVE

Surgical treatment of convexity meningiomas is usually considered a low-risk procedure. Nevertheless, the risk of postoperative motor deficits is higher (7.1%-24.7% of all cases) for lesions located in the rolandic region, especially when an arachnoidal cleavage plane with the motor pathway is not identifiable. The authors analyzed the possible role of navigated transcranial magnetic stimulation (nTMS) for planning resection of rolandic meningiomas and predicting the presence or lack of an intraoperative arachnoidal cleavage plane as well as the postoperative motor outcome.

METHODS

Clinical data were retrospectively collected from surgical cases involving patients affected by convexity, parasagittal, or falx meningiomas involving the rolandic region, who received preoperative nTMS mapping of the motor cortex (M1) and nTMS-based diffusion tensor imaging (DTI) fiber tracking of the corticospinal tract before surgery at 2 different neurosurgical centers. Surgeons' self-reported evaluation of the impact of nTMS-based mapping on surgical strategy was analyzed. Moreover, the nTMS mapping accuracy was evaluated in comparison with intraoperative neurophysiological mapping (IONM). Lastly, we assessed the role of nTMS as well as other pre- and intraoperative parameters for predicting the patients' motor outcome and the presence or absence of an intraoperative arachnoidal cleavage plane.

RESULTS

Forty-seven patients were included in this study. The nTMS-based planning was considered useful in 89.3% of cases, and a change of the surgical strategy was observed in 42.5% of cases. The agreement of nTMS-based planning and IONM-based strategy in 35 patients was 94.2%. A new permanent motor deficit occurred in 8.5% of cases (4 of 47). A higher resting motor threshold (RMT) and the lack of an intraoperative arachnoidal cleavage plane were the only independent predictors of a poor motor outcome (p = 0.04 and p = 0.02, respectively). Moreover, a higher RMT and perilesional edema also predicted the lack of an arachnoidal cleavage plane (p = 0.01 and p = 0.03, respectively). Preoperative motor status, T2 cleft sign, contrast-enhancement pattern, and tumor volume had no predictive value.

CONCLUSIONS

nTMS-based motor mapping is a useful tool for presurgical assessment of rolandic meningiomas, especially when a clear cleavage plane with M1 is not present. Moreover, the RMT can indicate the presence or absence of an intraoperative cleavage plane and predict the motor outcome, thereby helping to identify high-risk patients before surgery.

Predictors of postoperative motor function in rolandic meningiomas

OBJECTIVE

Resection of supratentorial meningiomas is generally considered a low-risk procedure, but tumors involving the rolandic cortex present a unique challenge. The rate of motor function deterioration associated with resecting such tumors is not well described in the literature. Thus, the authors sought to report the rates and predictors of postoperative motor deficit following the resection of rolandic meningiomas to assist with patient counseling and surgical decision-making.

METHODS

An institution's pathology database was screened for meningiomas removed between 2000 and 2017, and patients with neuroradiological evidence of rolandic involvement were identified. Parameters screened as potential predictors included patient age, sex, preoperative motor severity, tumor location, tumor origin (falx vs convexity), histological grade, FLAIR signal (T2-weighted MRI), venous involvement (T1-weighted MRI with contrast), intratumoral hemorrhage, embolization, and degree of resection (Simpson grade). Variables of interest included preoperative weakness and postoperative motor decline (novel or worsened permanent deficit). The SPSS univariate and bivariate analysis functions were used, and statistical significance was determined with alpha < 0.05.

RESULTS

In 89 patients who had undergone resection of convexity (80.9%) or parasagittal (19.1%) rolandic meningiomas, a postoperative motor decline occurred in 24.7%. Of 53 patients (59.6%) with preoperative motor deficits, 60.3% improved, 13.2% were unchanged, and 26.4% worsened following surgery. Among the 36 patients without preoperative deficits, 22.2% developed new weakness. Predictors of preoperative motor deficit included tumor size (41.6 vs 33.2 cm3, p = 0.040) and presence of FLAIR signal (69.8% vs 50.0%, p = 0.046). Predictors of postoperative motor decline were preoperative motor deficit (47.2% vs 22.2%, p = 0.017), minor (compared with severe) preoperative weakness (25.6% vs 21.4%, p < 0.001), and preoperative embolization (54.5% vs 20.5%, p = 0.014). Factors that trended toward significance included parafalcine tumor origin (41.2% vs 20.8% convexity, p = 0.08), significant venous involvement (44.4% vs 23.5% none, p = 0.09), and Simpson grade II+ (34.2% vs 17.6% grade I, p = 0.07).

CONCLUSIONS

Resection of rolandic area meningiomas carries a high rate of postoperative morbidity and deserves special preoperative planning. Large tumor size, peritumoral edema, preoperative embolization, parafalcine origin, and venous involvement may further increase the risk. Alternative surgical strategies, such as aggressive internal debulking, may prevent motor decline in a subset of high-risk patients.

Optimal surgical strategy for meningiomas involving the superior sagittal sinus: a systematic review

Involvement of the superior sagittal sinus (SSS) by meningiomas poses specific challenges, without an agreement about the degree of surgical aggressiveness when dealing with these lesions. In this systematic review and meta-analysis, we compare outcomes and complication rates, after different surgical strategies. Studies focused on meningiomas involving the SSS were collected from numerous online databases. Surgical outcome and complication data were abstracted. Comparisons were made considering complication and recurrence rates between an "aggressive" and a "non-aggressive" surgical attitude. A total of 26 studies, encompassing 1614 patients, were identified. Most of the tumors (53%) arose from the middle third of SSS and 75% of patients had a patent sinus at the time of surgery. A favorable outcome was achieved in 73% of patients treated with an "aggressive" surgical attitude compared to 78% of patients treated with a "non-aggressive" surgical attitude. Complication rates were similar between "aggressive" and "non-aggressive" attitudes, except for a higher rate of venous infarct (4% versus 2%, respectively) and worsening of preexisting motor deficits (34% versus 13%, respectively) in aggressively treated patients. Recurrence rates were not substantially different in the two groups after accounting for length of follow-up. Patients with incomplete resection (Simpson grades II-V) or with high histological grade (WHO grade III) had significantly higher recurrence rates. A complete resection achieves higher rates of tumor control, however, without nullifying the risk of recurrence. Moreover, "aggressive" tumor removal is associated with higher rates of venous complications and worsening of preexisting motor deficits.

Long-term follow-up of motor function deterioration following microsurgical resection of middle third parasagittal and falx meningioma

Background

Incidence of parasagittal meningioma varies in literature; it ranges from 16.8% to 25.6% of intracranial meningioma. Parafalcine meningioma accounts for about 8.5% of intracranial meningioma. Based on their relation to the superior Sagittal sinus and falx, these tumors had been classified into 3 groups; anterior third located between crista galli and coronal suture, middle third located between coronal and lambdoid sutures, and posterior third located posterior to lambdoid suture.

Methods

Seventeen cases of middle third parasagittal and falx meningioma operated between 2010 and 2014 were retrospectively reviewed; extent of resection was expressed according to Simpson’s classification. Medical Research Council Grading System was used for assessment and evaluation of motor power during preoperative, postoperative, and long-term follow-up, and patients were divided into two groups: group A, no preoperative motor deficit, and group B, patients with preoperative motor deficit. Based on this grading system, we classified motor function into three categories as follows: no disability, partial disability but independent, and complete disability. Follow-up period ranged between 14 and 48 months with mean period 32 months.

Results

Total number of patients was 17, 10 females and 7 males. Age ranged between 38 and 63 with the mean age 47. Twelve cases were parasagittal meningioma and 5 cases were falx meningioma. All located at the middle one third. Family history was negative in all cases. Duration of presenting symptoms varied between 3 and 28 months; presenting symptoms were as follows: seizures 64.7% (11 patients), headache 52.9% (9 patients), motor weakness 47% (8 cases), and disturbed conscious level 5.9% (1 case). According to Simpson’s classification, grade I resection was obtained in 4 patients and grade II in 13 patients. Intraoperative sinus invasion was present in 3 patients. In early postoperative outcome regarding motor function, 9 cases (53%) showed deterioration of motor function in group A: 4 patients out of 9, and group B: 4 patients out of 8. On long-term follow-up of patients with deteriorated motor function, 6 patients out of 9 improved (66%).

Conclusions

Parasagittal and falx meningioma involving the middle third is associated with a higher incidence of motor function deterioration either as a presenting symptom or during postoperative period. Adobting the microsurgical techniques during surgical resection and preservation of integrity of the venous system and cerebral cortex, deterioration of motor function is transient in most of cases with a favorable outcome on long-term follow-up.

Microsurgical treatment for central gyrus region meningioma with epilepsy as primary symptom

Background

The objective of this article was to investigate the operation outcome, complications, and the patient’s quality of life after surgical therapy for central gyrus region meningioma with epilepsy as the primary symptom.

Methods

All patients get at least 6 months of follow-up (range, 6–34 mo) after surgery. They underwent preoperative magnetic resonance imaging and video electroencephalography, and their clinical manifestations, imaging characteristics, microsurgical methods, and prognosis were retrospectively analyzed.

Results

The meningioma was located in the front and back of the central sulcus vein in 3 and 2 patients, respectively; in the compressed precentral gyrus and central sulcus vein in 3 patients; and in the precentral gyrus and postcentral gyrus each in 1 patient; beside the right sagittal sinus and invaded a thick draining vein on the brain surface in 1 patient and beside the right sagittal sinus and close to the precentral gyrus in 2 patients; invaded the superior sagittal sinus in 8 patients; crossed the cerebral falx and compressed cortex gyrus veins in 1 patient; invaded duramater and irritated skull hyperplasia in 3 patients; invaded duramater and its midline infiltrated into the superior sagittal sinus, was located behind the precentral gyrus, and enveloped the central sulcus vein. They were resected and classified by Simpson standards: 17 of the 26 patients had grade I, 6 patients had in grade II, and 3 patients had in grade III.

Conclusions

Resection of central gyrus region meningioma by microsurgical technique avoids injury to the cerebral cortex, central sulcus vein, and other draining veins. Microsurgery improves the total resection rate, reduces recurrence rate, and lowers disability or death rate.