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.