Objective:

To systematically investigate the incidence of somatosensory aura (SSAs) in epilepsy.

Background:

SSAs are characterized by abnormal sensations on one or more body parts that may spread following a somatotopic pattern.

Design/Methods:

Six databases were used to find the studies in electronic form about somatosensory auras in epilepsy, published until June 2024. Science Direct, Embase, Lilacs, Google Scholar, PubMed, and Scielo were searched. The terms used for the search were “somatosensory, aura, epilepsy.” There was no language restriction. Studies including the incidence of SSAs during one year were included, and the data was adjusted according to sample size.

Results:

20 studies containing 12927 patients with epilepsy were found. 695 patients developed at least one episode of SSAs in a period of one year. The incidence of SSAs was 5.38% (538 had SSAs for every 10000 individuals with epilepsy) during a period of one year. The occurrence of SSAs among individuals with epilepsy ranged 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 SSAs is paresthetic, followed by painful and thermal auras. In the primary SSAs, sensations occur more commonly contralaterally, while the secondary SSAs can be ipsilateral or bilateral. Despite the high localizing features of SSAs, cortical stimulation studies have shown overlapping sensations originating in the insula and the supplementary sensorimotor area.

Conclusions:

There was a wide variability in the incidence of SSAs in the studies from the literature. Some of the epilepsy mimics that should be considered in patients with SSAs are Alice-in-Wonderland syndrome, psychogenic non-epileptic paroxysmal events, syncope, migraine, and cerebrovascular non-epileptic paroxysmal events.