Atypical language localization in right temporal lobe epilepsy: An fMRI case report

Area of Science:

• Neuroscience
• Neurosurgery
• Epileptology

Background:

• Drug-resistant epilepsy necessitates precise presurgical planning.
• Left-handed individuals have a higher likelihood of atypical language lateralization.
• Presurgical functional magnetic resonance imaging (fMRI) aids in localizing critical brain functions.

Observation:

• A 41-year-old left-handed patient with drug-resistant right temporal lobe epilepsy (TLE) underwent presurgical fMRI.
• fMRI revealed bilateral language activation (Broca's and Wernicke's areas) and eloquent cortex near the planned resection site.
• Intraoperative direct cortical stimulation (DCS) during awake surgery confirmed language deficits in the targeted right temporal lobe region.

Findings:

• The patient exhibited language abnormalities, including paraphasic errors and speech arrest, during DCS.
• The planned anterior temporal lobectomy was aborted due to identified language function in the right hemisphere.
• A selective amygdalohippocampectomy was successfully performed, resulting in seizure freedom without neurological deficits.

Implications:

• Supports the necessity of detailed presurgical language mapping in left-handed patients with epilepsy.
• Demonstrates the critical role of fMRI and DCS in preventing intraoperative complications.
• Informs neurosurgical decision-making for patients with atypical language lateralization, improving surgical outcomes.