Internal and external spheno-orbital meningioma varieties: different outcomes and prognoses

Acta Neurochir (2016) 158:1587–1596

Internal variation among spheno-orbital meningiomas  (SOM) is surgically challenging. Optic canal invasion  management is discussed.

Method This retrospective study includes 70 patients with  SOM who underwent surgery between 1995 and 2012.  Preoperative ophthalmological, neurological and aesthetic  clinical signs were collected. All patients benefitted from repeated  tomography and magnetic resonance imaging (MRI).  The surgical team consisted of a neurosurgeon and a plastic  surgeon. In the majority of cases, resection was followed by  bone reconstruction using an autologous iliac crest graft. The  extent of resection was evaluated on the dural and osseous  sides. Early clinical outcomes, long-term follow-up, recurrence  and adjuvant therapies were reported.

Results The mean age was 52 years old, and 91 % of the  patients were women. Initial symptoms primarily included  proptosis (65 %), decreased visual acuity (39 %) and soft  tissue tumefaction (16 %).We classified 40 cases as the internal  variety when considering the inner third of the greater  wing of the sphenoid, optic canal, anterior clinoid process or  cavernous sinus. The remaining cases were described as the  external variety. The complete resection rates for the internal  and external varieties were 12 % and 61 %, respectively  (P< 0.001). In total, 90% of cases were grade I meningiomas.  For grade I, we reported 30 % recurrence, and 50 % of these  cases recurred in the first 2 years. Grade II cases without early  adjuvant radiotherapy increased at 2 years.We did not observe  any difference in recurrence rate among grade I tumours with  or without tumour remnants. At the end of follow-up, visual  acuity was stabilised or increased in 88 % of patients. In addition,  14 % of patients experienced persistent pain at the  location of the iliac harvesting site.

Conclusions The internal SOM variety exhibited a reduced  total resection rate and a shorter progression-free survival  (PFS). Unroofing of the optic canal extended PFS. Among  grade I cases, the persistence of a negligible tumour remnant  did not alter the probability of recurrence. For superior grades,  radiotherapy must be administered in addition to surgery as  soon as possible. SOMs require prolonged follow-up.  Autologous iliac reconstruction is related to substantial morbidity  and could be replaced by prosthetic bone threedimensional  reconstruction.