OVERVIEW

 Planum sphenoidale meningioma is a tumor that originates in the front part of the skull base or the anterior fossa skull base. The tumor arises from the meninges in the bone plateau (planum sphenoidale) just in front of the optic nerves in the skull base. These tumors are hidden deep under the middle part of the frontal lobes of the brain and have the potential to grow to formidable size before coming to medical attention. Planum sphenoidale meningiomas often have a close relation to the olfactory nerves, optic nerves , and to important cerebral arteries (carotid arteries, anterior cerebral arteries). They can cause significant pressure and swelling or edema of the frontal lobes of the brain, leading to disabling cognitive dysfunction.

PRESENTATION

Planum sphenoidale meningioma can present acutely with seizures or more insidiously with headache, progressive cognitive and behavioral changes. Patients can develop emotional flatness or aggressive, incoherent behavior. Another common complaint is loss of smell and taste related to olfactory nerve compression. In addition, as the tumor progresses, it can compress the optic nerves, causing visual difficulties.

MANAGEMENT

Given the large size of Planum sphenoidale meningiomas, often associated with visual difficulties, the management of these tumors generally requires surgical intervention. Other forms of treatment, such as radiation or observation, are commonly not possible or advisable for large tumors as primary treatment. 

SURGICAL DIFFICULTIES

Tumor size

Swelled frontal lobes covering the tumor.

Proximity to important brain arteries(Carotid arteries and anterior cerebral arteries)

Proximity to optic nerves

Deep location under the brain

SURGICAL MANAGEMENT AT THE CENTER FOR MENINGIOMA SURGERY

Option # 1

At the CENTER FOR MENINGIOMA SURGERY, we conceptualized the focal orbital approach, which can be used for the removal of planum sphenoidale meningiomas. This approach, associated with microsurgical technique and the extradural navigation concept, allows access to these deep and large tumors without hazardous exposure, direct manipulation, or retraction of the brain, which permits maximal functional recovery. In selected cases, the focal orbital approach can be done through a small eyebrow incision. The approach allows for early identification and full decompression of the optic nerves, which maximizes the chances of visual recovery. Early identification of the carotid arteries decreases the chance of unwanted arterial lesions with possible devastating consequences. Moreover, this minimal surgical approach enhances the potential for complete resection of the tumor, including its meningeal root at the planum sphenoidale.

Option # 2

At the CENTER FOR MENINGIOMA SURGERY, the endoscopic transnasal approach is an option for selected cases of small planum sphenoidale meningiomas. This approach allows access to the root of the tumor through the nostrils with an endoscope without any manipulation of the brain. This approach uses a multidisciplinary team with the participation of our ENT endoscopic nasal surgery specialist and neurosurgeon.

PROGNOSIS

Full or partial recovery of visual difficulties and cognitive and behavioral dysfunction is possible with adequate surgical management of planum sphenoidale meningioma using the focal orbital approach or the endoscopic nasal approach. The patients have the potential for returning to their pre-morbid lifestyle and job occupation. Maximal removal of the tumor and its meningeal root maximizes the chances of cure without tumor recurrence.