Purpose: We describe a patient with complex partial seizure with unidirectional olfactory aura associated with ipsilateral unruptured aneurysm.
Methods and results: The patient felt a sweet pleasant smell coming from behind her right side every time before the attack. Cranial magnetic resonance imaging (MRI) and three-dimensional computed tomography (CT) angiography revealed a large aneurysm at the bifurcation of the right middle cerebral artery and compression of the right orbitofrontal cortex. Small spikes were recorded from the right orbitofrontal and superior temporal gyri and from the uncus by the cortical electrodes during clipping of the aneurysm.
Conclusions: The orbitofrontal cortex may have a function related to the ipsilateral directional olfactory sensation.