Sphenoid wing meningiomas, or ridge meningiomas, are the most common of the basal meningiomas.
This anterior skull base meningioma has a relative incidence of 17%.
This tumor usually arises from the lesser wing of the sphenoid bone.
Cushing and Eisenhardt were the first to describe sphenoid wing meningiomas in detail, categorizing globoid tumors into 3 groups: 1) medial; 2) middle; and 3) lateral.
Tumors found in the external third of the sphenoid are of two types: en-plaque and globoid meningiomas.
Patients with globoid meningiomas often present only with signs of increased intracranial pressure. This leads to various other symptoms including headache and a swollen optic disc.
Following the physical exam, the diagnosis is confirmed with neuro-imaging. Either a head CT or MRI with contrast such as gadolinium is useful, as meningiomas often show homogenous enhancement. Angiography looking for signs like stretched arteries may be used to supplement evaluation of vascular involvement and to determine whether embolization would be helpful if surgery is being considered.
On MRI imaging, T1- and T2-weighted sequences have variable signal intensity, but they enhance intensely and homogeneously after injection of gadolinium. They also tend to exhibit hyperostosis and calcifications which can be seen on either CT or MRI imaging. Additionally, the presence of a dural extension (also known as a dural tail) is helpful in distinguishing a meningioma from fibrous dysplasia
The differential diagnosis for sphenoid wing meningioma includes other types of tumors such as optic nerve sheath meningioma, cranial osteosarcoma, metastases, and also sarcoidosis.
Endo et al. report the utility of a pulsed water jet device in meningioma surgery. The presented case is that of a 61-year-old woman with left visual disturbance. MRI demonstrated heterogeneously enhanced mass with intratumoral hemorrhage, indicating sphenoid ridge meningioma on her left side. The tumor invaded the cavernous sinus and left optic canal, engulfing the internal carotid artery in the carotid cistern and encased middle cerebral arteries. During the operation, the pulsed water jet device was useful for dissecting the tumor away from the arteries since it was safe in light of preserving parent arteries. The jet did not cause any vascular injury and did not induce vasospasm as shown by postoperative symptomatology and MRIs. With the aid of pulsed water jet, we could achieve total resection of the tumor except for the piece within the cavernous sinus. The patient had no new neurological deficits after the operation 1).