They often cause focal epilepsy and later paralysis, especially of the lower extremities. Falcine Meningiomas Tumors arising from the falx are located in the midline and often extend to both sides of the brain. These tumors are difficult to remove totally and often recur after surgery. Olfactory Groove Olfactory groove meningiomas arise from the cribriform plate. They grow bilaterally and become large without causing significant neurologic deficits or evidence of increased intracranial pressure.
Loss of smell can often be the only symptom.
Changes in mental status are seldom striking until the tumor has reached a large size. Once the tumor becomes large it impinges on the optic nerves and chiasm resulting in visual loss. These meningiomas arise from the planum sphenoidale, tuberculum sellae or the diaphragm sellae. They cause early and characteristic visual failure. Typically, loss of visual acuity and field is progressive and asymmetric, although it can be sudden.