Article type: Literature Review
Article title: Somatosensory Auras in Epilepsy: A Narrative Review of the Literature
Journal: Medicines
Year: 2023
Authors: Ana Leticia Fornari Caprara, Hossam Tharwat Ali, Ahmed Elrefaey, Sewar A. Elejla, and Jamir Pitton Rissardo
E-mail: jamirrissardo@gmail.com
ABSTRACT
An aura is a subjective experience felt in the initial phase of a seizure. Studying auras is relevant as they can be warning signs for people with epilepsy. The incidence of aura tends to be underestimated due to misdiagnosis or underrecognition by patients unless it progresses to motor features. Also, auras are associated with seizure remission after epilepsy surgery and are an important prognostic factor, guiding the resection site and improving surgical outcomes. Somatosensory auras (SSAs) are characterized by abnormal sensations on one or more body parts that may spread to other parts following a somatotopic pattern. The occurrence of SSAs among individuals with epilepsy can range from 1.42% to 80%. The upper extremities are more commonly affected in SSAs, followed by the lower extremities and the face. The most common type of somatosensory aura is paresthetic, followed by painful and thermal auras. In the primary somatosensory auras, sensations occur more commonly contralaterally, while the secondary somatosensory auras can be ipsilateral or bilateral. Despite the high localizing features of somatosensory areas, cortical stimulation studies have shown overlapping sensations originating in the insula and the supplementary sensorimotor area.
Keywords: aura; seizure; epilepsy; focal epilepsy; seizure semiology; EEG; MRI; somatosensory; paresthesia; painful
Full text available at:
DOI
10.3390/medicines10080049
Citation
Caprara ALF, Tharwat Ali H, Elrefaey A, Elejla SA, Rissardo JP. Somatosensory Auras in Epilepsy: A Narrative Review of the Literature. Medicines 2023;10:49.
Figure 1. Primary somatosensory area (SI) and secondary sensory area (SII).
Figure 2. Localization of clinical responses with electrocortical stimulation of the insula. Long gyrus of the insula (1, posterior long gyrus of the insula; 2, postcentral insular sulcus; 3, anterior long gyrus of the insula), central insular sulcus (4), short gyri of the insula (5, posterior short gyrus of the insula; 6, precentral insular sulcus; 7, middle short gyrus of the insula; 8, short insular sulcus; 9, anterior short gyrus of the insula), and accessory gyrus of the insula (11) and sulcus (10).
Figure 3. Types of painful auras and corresponding theories.
Table 2. Localization and lateralization of somatosensory auras by Rona et al. [89] and Perven et al. [90], adapted by Caprara et al.
Table 3. Epilepsy Mimics in a total of 906 patients in 18 studies, according to Xu et al. 2016 [104].