Due to the subtle symptoms prior to clinical presentation, olfactory groove meningiomas can grow insidiously large and present as one of the largest intracranial tumors.
Olfactory groove meningiomas most commonly present with symptoms of headaches, anosmia, or even possibly personality changes. The anatomic location of the olfactory groove meningioma may cause prolonged psychiatric symptoms before the onset of more overt neurologic deficits.
Subfrontal meningiomas grow insidiously in areas with high cerebral compliance and a relative scarcity of eloquent function. Symptoms develop progressively, are nonspecific, and include anosmia, changes in personality and cognition, depressive symptoms, headaches, visual disturbances, and seizures. Patients with subfrontal meningiomas carry the highest risk of developing psychological symptoms, which makes patient-reported outcomes in terms of long-term health-related quality of life (HRQOL), anxiety, and depression of particular importance 1).
They may produce progressive compression of the frontal lobes and project backward towards the sella, and if large enough, they can affect vision by compressing the optic nerve and chiasm 2).
Visual symptoms occur usually after an olfactory groove meningioma has reached a considerable size but can depend on their exact origin. Because olfactory groove meningiomas extend posteriorly, this extension can cause compression on one or both of the optic nerves or the chiasm, and may occur earlier in smaller tumors arising from the posterior half of the cribiform plate 3).