Olfactory groove meningioma with paranasal sinus and nasal cavity extension: removal by combined subfrontal and nasal approach

Nasofrontal meningiomas: retrospective series and review of literature

INTRODUCTION

Lesions affecting the anterior skull base and involving the paranasal sinuses (PNS), nasal cavity (NC), and orbit are infrequent and include predominantly a wide variety of sinonasal malignancies. Less than 3% of intracranial meningiomas extend extracranially and involve PNS and NC. Given their relatively low incidence, little is known about the treatment outcome of this subset of meningiomas.

METHODS

Systematic literature and retrospective review of own institutional series of midline anterior skull base meningiomas with significant PNS and NC involvement were performed.

RESULTS

Overall, 21 patients-16 in the literature review group and 5 of our institutional series-were included. Eleven (52.4%) patients had had a prior surgery for midline anterior skull base meningioma. Of patients having reported WHO grade, two were WHO II. Gross total resection was achieved in 16 (76.2%) of patients, utilizing solely transcranial approach in 15 patients, combined endoscopic and transcranial in five patients and purely endoscopic in one patient. Postoperative radiotherapy was administered in three (14.3%) patients, all after total resection via transcranial route, without a history of prior treatment. A postoperative cerebrospinal fluid leak was reported in four (10%) patients, requiring surgical repair in two. There were no reports of postoperative meningitis. No neurological complications were observed except of a reported worsening of vision in one patient.

CONCLUSION

Midline anterior skull base meningiomas infrequently extend significantly into the PNS and NC. Despite their significant involvement, along with concomitant involvement of orbit, gross total resection is possible in the majority of cases with low morbidity using either purely transcranial or combined endoscopic/transcranial approach.

The Extended Subfrontal and Fronto-Orbito-Zygomatic Approach in Skull Base Meningioma Surgery: Clinical, Radiologic, and Cosmetic Outcome

OBJECTIVE

To review the outcome and cosmetic results of patients undergoing extended subfrontal and fronto-orbito-zygomatic craniotomy for resection of skull base meningiomas.

METHODS

All surgeries were performed in cooperation with an oral and maxillofacial surgeon between 2006 and 2012. Clinical presentation, surgical techniques and complications, cosmetic, clinical, and radiologic outcomes are presented.

RESULTS

This study included 25 consecutive patients with 26 operations. Total and subtotal tumor removal was obtained in 19 (73.1%) and 7 (26.9%) patients, respectively. Permanent postoperative complications were seen in 5 (19.2%) patients. Eight of 10 patients with preoperative visual impairment showed recovery at 6 months follow-up. Anosmia was improved in 50% and no worsening was seen in any case of hyposmia. All patients showed improved or complete correction of exophthalmos, cognitive deficits, and epilepsy. One patient (3.8%) developed a postoperative ptosis. No mortality was documented. All patients reported a favorable cosmetic satisfactory score over 6 (8.67 ± 1.6). Tumor recurrence rate was 7.7% (n = 2).

CONCLUSIONS

The extended subfrontal and fronto-orbito-zygomatic approach, used for resection of meningiomas located in the orbita and the skull base can provide better visibility of the tumor. In addition, these approaches lead to highly satisfying cosmetic and clinical results.

Endoscopic Endonasal Approach for Olfactory Groove Meningiomas: Operative Technique and Nuances

Olfactory groove meningiomas represent approximately 10% of all intracranial meningiomas. Because these tumors originate at the ventral skull base, the endonasal route provides direct access to the tumor blood supply for early devascularization and removal of the underlying hyperostotic bone at the cranial base. In carefully selected patients, these tumors can be totally removed without additional brain retraction or manipulation. In this report, we describe the surgical technique and operative nuances for removal of olfactory groove meningiomas using the endoscopic endonasal approach, and also discuss the indications, limitations, complication avoidance and management, and postoperative care.

Comparison of endoscopic endonasal and bifrontal craniotomy approaches for olfactory groove meningiomas: A matched pair analysis of outcomes and frontal lobe changes on MRI

We compare the outcomes and postoperative MRI changes of endoscopic endonasal (EEA) and bifrontal craniotomy (BFC) approaches for olfactory groove meningiomas (OGM). All patients who underwent either BFC or EEA for OGM were eligible. Matched pairs were created by matching tumor volumes of an EEA patient with a BFC patient, and matching the timing of the postoperative scans. The tumor dimensions, peritumoral edema, resectability issues, and frontal lobe changes were recorded based on preoperative and postoperative MRI. Postoperative fluid-attenuated inversion recovery (FLAIR) hyperintensity and residual cystic cavity (porencephalic cave) volume were compared using univariable and multivariable analyses. From a total of 70 patients (46 EEA, 24 BFC), 10 matched pairs (20 patients) were created. Three patients (30%) in the EEA group and two (20%) in the BFC had postoperative cerebrospinal fluid leaks (p=0.61). Gross total resections were achieved in seven (70%) of the EEA group and nine (90%) of the BFC group (p=0.26), and one patient from each group developed a recurrence. On postoperative MRI, there was no significant difference in FLAIR signal volumes between EEA and BFC approaches (6.9 versus 13.3 cm(3); p=0.17) or in porencephalic cave volumes (1.7 versus 5.0 cm(3); p=0.11) in univariable analysis. However, in a multivariable analysis, EEA was associated with less postoperative FLAIR change (p=0.02) after adjusting for the volume of preoperative edema. This study provides preliminary evidence that EEA is associated with quantifiable improvements in postoperative frontal lobe imaging.

The Role of the Pterional Approach in the Surgical Treatment of Olfactory Groove Meningiomas: A 20-year Experience

Background Olfactory groove meningiomas remain surgically challenging. The common microsurgical approaches suffer from late exposure of the neurovascular structures. Conversely, the pterional approach has the advantage of early dissection of the posterior neurovascular complex. Methods We reviewed the records of patients treated for olfactory groove meningioma in our department between 1991 and 2010. A total of 61 patients underwent removal of olfactory groove meningiomas via the pterional approach. These included 58 primary and 3 recurrent tumors. Mean overall follow-up time was 122 months. Results Early exposure and dissection of the internal carotid artery, middle cerebral artery, anterior cerebral artery, and optic nerve was feasible in all cases. Complete tumor removal was achieved in 60 patients. Morbidity and mortality rates were 26% and 1.6% respectively. Postoperative complications included epileptic seizures (five patients) and cerebrospinal fluid (CSF) leak (two patients). During follow-up, we recorded three tumor recurrences. Conclusions The pterional approach appears to be an excellent solution for the treatment of olfactory groove meningiomas. Its foremost advantage is early visualization of the posterior neurovascular complex. Moreover, it allows frontal sinus preservation and timely tumor devascularization and avoids excessive brain retraction. The pterional view is familiar to most neurosurgeons and therefore the transition to this technique is fairly straightforward.

Giant olfactory groove meningiomas: extent of frontal lobes damage and long-term outcome after the pterional approach

OBJECTIVE

The treatment of giant olfactory groove meningiomas (OGMs; maximum diameter ≥ 6 cm) poses special problems and represents a surgical challenge. We discuss the long-term results in a series of 18 patients with giant OGMs and report our experience on a global strategy encompassing the pterional approach to manage the lesion and an extended transbasal approach to treat recurrences.

METHODS

Between February 1991 and December 2007, 18 patients with giant OGMs were surgically managed via a pterional craniotomy. Postoperative follow-up imaging was obtained at one, six, and 12 months and then yearly. In preoperative images, data from tumor volume were assessed. The volume of the residual right frontal porencephalic cave (ipsilateral to the operative side) was compared with the volume of the porencephalic cave measured in the left frontal lobe (internal control) in each case. Comparison between porencephalic cave and the original tumor volume for each side was also performed.

RESULTS

At the first operation in 17 of 18 patients (94.4%), the tumor resection was accomplished by a complete macroscopic lesion removal and coagulation of its dural attachment (Simpson grade II). In one patient, a Simpson grade V resection was obtained. The mean follow-up was 93.5 months, ranging from 12 to 214 months. Recurrences were observed in three patients (16.7%) at 103, 102, and 128 months, respectively, from the time of the first operation. These patients were operated on via an extended subfrontal transbasal approach accomplishing a complete (Simpson grade I) resection. No death occurred. The visual deficit improved in seven of 13 patients (53.8%), remained stable in five (38.5%), and worsened in one patient (7.7%). Overall, 17 of 18 patients (94.4%) had a good outcome and returned to their previous occupations. All the tumors presented with a symmetrical growth pattern. The mean meningioma volume was 23.51 ± 1.62 cm(3) for the right portion of the tumor and 23.04 ± 1.35 cm(3) for the left portion. The mean residual porencephalic volume was significantly smaller in the left frontal lobe (mean value 5.7 mL) than in the right frontal lobe (mean value 16.6 mL; P < 0.05). The mean residual porencephalic volume was significantly smaller than the tumor volume both in the left (P < 0.01) and in the right side (P < 0.05).

CONCLUSION

The pterional-transsylvian approach provides two major advantages: first, it minimizes morbidity and mortality through an early neurovascular control and by limiting parenchymal damage as demonstrated by a quantitative analysis; second it is associated with low recurrence rate at a long-term follow-up.

Surgical nuances for removal of olfactory groove meningiomas using the endoscopic endonasal transcribriform approach

Olfactory groove meningiomas represent 10% of intracranial meningiomas and arise in the midline of the anterior cranial fossa along the dura of the cribriform plate and planum sphenoidale. Hyperostosis of the adjacent underlying bone is common, and further extension into ethmoid sinuses and nasal cavity can occur in 15%-25% of cases. Radical tumor resection including the involved dural attachment and underlying hyperostotic bone offers the best chance of a Simpson Grade I resection to minimize recurrence. Incomplete removal of involved hyperostotic bone can result in tumor recurrence at the cribriform plate with extension into the paranasal sinuses. Resection has traditionally been performed using a bifrontal or pterional approach, both of which require some degree of brain retraction or manipulation to expose the tumor. The endoscopic endonasal transcribriform approach offers the most direct and immediate exposure to the tumor without brain retraction and manipulation of neurovascular structures. An endonasal "keyhole craniectomy" is performed in the ventral skull base directly over the basal dural attachment, extending from the posterior wall of the frontal sinus to the planum sphenoidale and tuberculum sellae in the anteroposterior plane, and from one medial orbit to the other in the coronal plane. Excellent panoramic visualization of the keyhole skull base defect can be obtained with a 30° endoscope after performing a modified Lothrop procedure. Because the dural attachment is adjacent to the paranasal sinuses, early devascularization and total Simpson Grade I removal of the tumor including the dural attachment and underlying hyperostotic bone can be achieved in properly selected patients. This approach is also very suitable for meningiomas that have recurred or extended into the paranasal sinuses. Extracapsular, extraarachnoid dissection of the tumor from the frontal lobes and neurovascular structures can be performed using conventional bimanual microsurgical techniques. In this report, we review the surgical technique and describe our operative nuances for removal of olfactory groove meningiomas, including recurrent tumors with extension into the nasal cavity, using a purely endoscopic endonasal transcribriform approach. In addition, we discuss the advantages, limitations, patient selection, and complications of this approach. We specifically highlight our technique for multilayer reconstruction of large anterior skull base dural defects using fascia lata and acellular dermal allograft supplemented by bilateral vascularized pedicled nasoseptal flaps. Three new cases of endoscopically resected olfactory groove meningiomas are also presented.

Atypical meningioma presenting as a nasal mass-multidisciplinary management

OBJECTIVE

To report a case of recurrent extracranial atypical meningioma successfully managed by a multidisciplinary team.

METHODS

Case report and literature review concerning successful management of recurrent extracranial meningioma based on pathology and extent of resection.

RESULTS

A 48-year-old woman who presented with a nasal mass, anosmia and headaches. Physical exam and imaging showed recurrent meningioma involving the entire anterior frontal meninges extending into the frontal bone and down into the nasal cavity via the anterior ethmoid. Combined modality surgical intervention was successful and the patient recovered suffering no neurological sequelae.

CONCLUSION

This is a very rare presentation of meningioma that the craniomaxillofacial surgeon should consider when formulating a differential diagnosis for a nasal mass. Long-term surveillance is crucial as recurrence can have devastating consequences. Aggressive multidisciplinary care is needed to prevent future recurrences and to improve survival.

Juvenile psammomatoid ossifying fibroma: a review

In WHO classification of odontogenic tumors (2005), juvenile ossifying fibroma (JOF) is divided into juvenile psammomatoid ossifying fibroma (JPOF) and juvenile trabecular ossifying fibroma (JTOF). JPOF has been distinguished because of its location, clinical behavior, and age of occurrence. It is generally seen in younger age group and the most common site is paranasal sinuses, orbits, and fronto-ethmoidal complex. Radiologically, the internal structure can be radiolucent, mixed, or radiopaque, depending on the degree of calcification and extent of the cystic changes. Histologically, it is characterized by a densely cellular fibrous stroma interspersed with numerous psammoma bodies. The treatment is "en bloc" surgical excision while in case of intracranial extension, tumor removal may need a combination of neurosurgical and transfacial approach. Malignant transformation and metastasis has not been reported but recurrence is common. The purpose of this narrative review article is to discuss the various aspects of JPOF reported in the English medical literature.

Transcranial resection of a large sinonasal juvenile psammomatoid ossifying fibroma

INTRODUCTION

Juvenile psammomatoid ossifying fibroma (JPOF) is a benign but potentially locally aggressive fibroosseous lesion predominantly arising in the paranasal sinuses in children and young adults. Intracranial extension is rare but occurs sometimes. In such cases, tumor resection may often require the combination of neurosurgical and facial approaches. Histological diagnosis remains a challenge because the lesion can be easily mistaken for another fibroosseous lesion or for a meningioma.

CASE REPORT

We report the case of a 12-year-old boy with a JPOF arising from the right paranasal sinuses and extension towards the anterior skull base and the orbit. Despite the tumor had eroded through nasal septum, medial orbit wall, and right maxilla, it could be entirely removed performing an extended frontobasal approach via a bifrontoorbital craniotomy, obviating the need for a transfacial approach.

CONCLUSION

Radiologically and histologically, the lesion could be mistaken either for a meningioma or another type of ossifying fibroma. Histological aspects and alternative surgical approaches to these rare entities are discussed.

LATERAL SUPRAORBITAL APPROACH APPLIED TO OLFACTORY GROOVE MENINGIOMAS

OBJECTIVE

The lateral supraorbital approach for safely and completely removing olfactory groove meningiomas was assessed.

METHODS

Between September 1997 and June 2008, a total of 656 meningiomas were operated on by the senior author (JH) at the Department of Neurosurgery, Helsinki University Central Hospital; 66 were olfactory meningiomas. We retrospectively analyze the clinical data, radiological findings, surgical treatment, histology, and outcome of all the olfactory groove meningioma patients and discuss the operative techniques used.

RESULTS

Sixty-six patients were operated on by the lateral supraorbital approach. The median preoperative Karnofsky Performance Scale score was 80 (range, 40–100). Three patients were redo cases in which the primary operation had been performed elsewhere. Seemingly complete tumor removal was achieved in 60 patients (91%); there was no surgical mortality. Postoperatively, 6 patients (9%) had cerebrospinal fluid leakage, 5 (8%) had new visual deficits, 4 (6%) had wound infections, 4 (6%) had cotton granulomas, and 1 (2%) had a postoperative hematoma. The median Karnofsky score at discharge was 80 (range, 40–100). Six patients had recurrent tumors; 3 underwent reoperations after an average of 21 months (range, 1–41 months); 1 was treated with radiosurgery, and 2 were only followed. During the median follow-up time of 45 months (range, 2–128 months), there were 4 recurrences (6%) diagnosed on average 32 months (range, 17–59 months) after surgery.

CONCLUSION

The lateral supraorbital approach can be used safely for olfactory groove meningiomas of all sizes with no mortality and relatively low morbidity. Surgical results and tumor recurrence with this fast and simple approach are similar to those obtained with more extensive, complex, and time-consuming approaches.

Giant olfactory groove meningioma: ophthalmological and cognitive outcome after bifrontal microsurgical approach

OBJECT

Olfactory groove meningiomas arise in the midline along the dura of the cribriform plate and may reach a large size before producing symptoms. We conducted a retrospective study of patients with these lesions focused on pre- and post-operative investigations for ophthalmological, personality and cognitive disturbances.

METHODS

The authors reviewed 36 patients with giant olfactory groove meningiomas surgically treated via a bifrontal approach. Ophthalmological evaluation included visual acuity, fundoscopy and visual fields while psychological evaluation included a Mini-Mental State Examination. Data was collected before, 1 and 12 months after surgery. Formal pre- and post-operative ophthalmological examinations discovered visual deficits in 55.5% of the patients. Within the first month after surgery, improvement of visual acuity and of visual field deficits was observed. In post-operative neuropsychological testing, higher mental functions showed improvement. The most frequent post-operative complication was persistent rhinorrhoea in two patients.

CONCLUSIONS

Results at longest follow up indicate that cognitive changes and visual deficits will improve in patients with giant olfactory groove meningiomas after a bifrontal approach, without additional neurological deficits.

Olfactory groove meningiomas: functional outcome in a series treated microsurgically

BACKGROUND

A systematic investigation of long-term follow-up results after microsurgical treatment of patients harbouring an olfactory groove meningioma, particularly with regard to postoperative olfactory and mental function, has rarely been performed. We reassessed a series of patients treated microsurgically for an olfactory groove meningioma in regard to clinical presentation, surgical approaches and long-term functional outcome.

METHOD

Clinical, radiological and surgical data in a consecutive series of 56 patients suffering from olfactory groove meningioma were retrospectively reviewed.

FINDINGS

Presenting symptoms of the 41 women and 15 men (mean age 51 years) were mental changes in 39.3%, visual impairment in 16.1% and anosmia in 14.3% of the patients. Preoperative neurological examination revealed deficits in olfaction in 71.7%, mental disturbances in 55.4% and reduced vision in 21.4% of the cases. The tumour was resected via a bifrontal craniotomy in 36, a pterional route in 13, a unilateral frontal approach in 4 and via a supraorbital approach in 3 patients. Extent of tumour resection according to Simpson's classification system was grade I in 42.9% and grade II in 57.1% of the cases. After a mean follow-up period of 5.6 years (range 1-13 years) by clinical examination and magnetic resonance imaging (MRI), 86.8% of the patients resumed normal life activity. Olfaction was preserved in 24.4% of patients in whom pre- and postoperative data were available. Mental and visual disturbances improved in 88 and 83.3% of cases, respectively. Five recurrences (8.9%) were observed and had to be reoperated.

CONCLUSIONS

Frontal approaches allowed better resection of tumours with gross infiltration of the anterior cranial base, tumours extending into the ethmoids or nasal cavity and in cases with deep olfactory grooves. Preservation of olfaction should be attempted in patients with normal or reduced smelling preoperatively.

Olfactory groove meningiomas from neurosurgical and ear, nose, and throat perspectives: approaches, techniques, and outcomes

OBJECTIVE

To review the surgical approaches, techniques, outcomes, and recurrence rates in a series of 80 olfactory groove meningioma (OGM) patients operated on between 1990 and 2003.

METHODS

Eighty patients underwent 81 OGM surgeries. Tumor diameter varied from 2 to 9 cm (average, 4.6 cm). In 35 surgeries (43.2%), the tumor was removed through bifrontal craniotomy; nine operations (11.1%) were performed through a unilateral subfrontal approach; 18 surgeries (22.2%) were performed through a pterional approach; seven surgeries (8.6%) were carried out using a fronto-orbital craniotomy; and 12 procedures (14.8%) were accomplished via a subcranial approach. Nine patients (11.3%) had undergone surgery previously and had recurrent tumor.

RESULTS

Total removal was obtained in 72 patients (90.0%); subtotal removal was achieved in 8 patients (10.0%). Two patients, one with total and one with subtotal removal, had atypical (World Health Organization Grade II) meningiomas, whereas 78 patients had World Health Organization Grade I tumors. There was no operative mortality and no new permanent focal neurological deficit besides anosmia. Twenty-five patients (31.3%) experienced surgery-related complications. There were no recurrences in 75 patients (93.8%) 6 to 164 months (mean, 70.8 mo) after surgery. Three patients (3.8%) were lost to follow-up. In two patients (2.5%) with subtotal removal, the residual evidenced growth on computed tomography and/or magnetic resonance imaging 1 year after surgery. One of them had an atypical meningioma. The second, a multiple meningiomata patient, was operated on twice in this series.

CONCLUSION

A variety of surgical approaches are used for OGM resection. An approach tailored to the tumor's size, location, and extension, combined with modern microsurgical cranial base techniques, allows full OGM removal with minimal permanent morbidity, excellent neurological outcome, and very low recurrence rates.

Meningeoma de goteira olfatória: relação entre achados clínico-radiológicos e índice proliferativo (Mib-1)

OBJETIVO: O objetivo deste estudo é correlacionar achados clínicos, radiológicos e índice proliferativo em meningeomas da goteira olfatória e analisar possíveis fatores preditivos de recidiva tumoral. MÉTODO: Foram estudados 15 pacientes portadores de meningeoma de goteira olfatória. O exame imuno-histoquímico foi realizado através do índice proliferativo calculado a partir da expressão do MIB-1. RESULTADOS: Houve relação estatisticamente significativa entre volume tumoral e edema. Não houve relação significativa entre índice proliferativo, volume tumoral, edema, idade do paciente e alterações da base do crânio. Dois pacientes que apresentaram recidiva tumoral possuíam índice proliferativo maior que a média. CONCLUSÃO: Tumores maiores são mais susceptíveis ao desenvolvimento de edema cerebral. O índice proliferativo provavelmente está associado a recidiva tumoral, principalmente em pacientes com hiperostose e ressecções cirúrgicas parciais.

Meningeoma da goteira olfatória

Meningeomas da goteira olfatória representam 8-18% dos meningeomas intracranianos e geralmente são diagnosticados quando alcançam grande tamanho. Relatamos uma série de 13 casos consecutivos de meningeomas de goteira olfativa operados nos Hospitais São Paulo (UNIFESP) e Professor Edmundo Vasconcelos no período de 1995 a 2003, estudados retrospectivamente quanto ao quadro clínico, resultados cirúrgicos e complicações. Os pacientes foram submetidos a ressecção cirúrgica destes tumores pela via subfrontal, em 9 casos a ressecção foi completa incluindo dura-máter e osso infiltrado por tumor e em 4 a dura-máter foi somente coagulada. Um paciente morreu devido a infarto cerebral e três pacientes evoluíram com fístulas liquóricas. Não houve recorrência sintomática no período que variou de 11 meses a 8 anos. Com as técnicas microcirúrgicas atuais, estes tumores podem ser removidos com baixa morbidade.

Imaging of chemosensory loss

Clinical assessment of olfactory dysfunction can be challenging. Because olfactory disturbances comprise most chemosensory abnormalities with imaging findings, this article focuses on the imaging of smell disorders. This article reviews the normal imaging appearance of the olfactory apparatus, discusses the respective roles of CT and MRI, provides illustrative imaging of typical pathologic lesions, and discusses a clinically based imaging strategy.

Recurrence of olfactory groove meningiomas

OBJECTIVE

Despite apparent gross total resection, olfactory groove meningiomas have a high rate of late recurrence (average, 23%). In this retrospective study, we confirmed that the sites of these recurrences are the cranial base and paranasal sinuses. We postulated that these recurrences stem from conservative handling of the underlying invaded bone. Therefore, we analyzed patient outcomes according to the radicality of surgical resection.

METHODS

Fifteen consecutive patients with a diagnosis of olfactory groove meningioma were treated surgically between 1992 and 2001 (nine new cases, six recurrent). Only patients with benign meningiomas were included; atypical and malignant meningiomas were excluded. Surgical resection included the dura and drilling of the underlying bone and resection of involved mucosa. We reviewed each patient's clinical records, radiological studies, sites of recurrence, grade of previous resection, and complications.

RESULTS

Olfactory groove meningiomas invaded the underlying bone in 13 cases. All patients with recurrence had previously undergone a surgical resection corresponding only to Simpson Grade 2, which does not include the removal of underlying invaded bone. The sites of recurrence were in the cranial base or adjacent paranasal sinuses. The time to recurrence varied from 1 to 12 years (average, 7 yr; mean, 8 yr). Three patients had undergone one previous resection, two had undergone two previous resections, and one had undergone four previous operations. The ethmoid sinus was involved in all cases of recurrence, either with the sphenoid sinus or with an intracranial recurrence. Thirteen patients underwent complete resection of underlying bone and the invaded paranasal sinuses, then reconstruction of the anterior fossa. No patient died. There were three instances of cerebrospinal fluid leakage (one requiring operative repair), one case of delayed worsening vision after initial improvement, and two cases of transient cranial nerve palsy (Cranial Nerves III and IV). There was no recurrence at follow-up (average, 3.7 yr; range, 1-7.3 yr).

CONCLUSION

The cranial base and paranasal sinuses are sites of predilection for recurrence of olfactory groove meningiomas. Recurrence is the result of a direct extension attributable to incomplete resection of involved bone and regrowth at the edge of a previous surgical field. Extensive resection of all suspicious underlying bone is a complement to radical removal of these lesions. Reconstruction with a vascularized pericranial flap to prevent cerebrospinal fluid leakage is crucial.