Seizure-associated aphasia has good lateralizing but poor localizing significance

Epilepsia. 2017 Sep;58(9):1551-1555. doi: 10.1111/epi.13835. Epub 2017 Jul 4.

Abstract

Objective: To investigate the occurrence of ictal and postictal aphasia in different focal epilepsy syndromes.

Methods: We retrospectively analyzed the video-electroencephalographic monitoring data of 1,118 patients with focal epilepsy for seizure-associated aphasia (SAA). Statistical analysis included chi-square analysis and Fisher's exact test.

Results: We identified 102 of 1,118 patients (9.1%) in whom ictal or postictal aphasia (SAA) was part of their recorded seizures (n = 59 of 102; 57.8%) or who reported aphasia by history (n = 43; 42.2% only reported aphasia by history). Postictal aphasia was present in 18 patients (30.5%). Six of the 59 patients had both ictal and postictal aphasia (10.2%). SAA occurred either with left hemisphere seizure onset or with seizures spreading from the right to the left hemisphere. SAA was most common in patients with parieto-occipital epilepsy (10.9%; five of 46 patients), followed by patients with temporal (6.7%; 28 of 420 patients), focal (not further localized; 4.8%; 22 of 462 patients), and frontal epilepsy (2.1%; four of 190 patients; p = 0.04). SAA was more common in parieto-occipital epilepsy than in frontal epilepsy (p = 0.02). In contrast, there was no significant difference in SAA between temporal and parieto-occipital epilepsy (p = 0.36).

Significance: SAA has a high lateralizing but limited localizing value, as it often reflects spread of epileptic activity into speech-harboring brain regions.

Keywords: Anomia; Aphasia; Epilepsy surgery; Lateralizing seizure phenomenon; Semiology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aphasia / etiology*
  • Aphasia / physiopathology
  • Brain / physiopathology
  • Electroencephalography
  • Epilepsies, Partial / complications
  • Epilepsies, Partial / physiopathology
  • Humans
  • Neuroimaging
  • Positron-Emission Tomography
  • Retrospective Studies
  • Seizures / complications*
  • Seizures / physiopathology
  • Tomography, Emission-Computed, Single-Photon