Introduction: Epilepsy affects close to 2.5 to 3 million people. The majority of those patients suffer from temporal lobe epilepsy associated with mesial temporal sclerosis (MTS). These patients often report a variety of sensations called auras prior to ictal events. In this study, we investigated how preoperative MRI and pathological findings relate to the different types of auras, and examine those auras for their predictive value of postsurgical outcome
Methods: Patients who underwent anterior temporal lobectomies (n = 275) from 1993 to 2016 at Massachusetts General Hospital were retrospectively reviewed with an average length of follow up of 8.24 years.
Results: 57.96% of the patients for whom data was available are currently seizure free, while 42.04% relapsed. 195 (86%) of patients reported experiencing auras whereas 32 (14.1%) patients denied auras of any type. Notably, 60 patients reported epigastric auras (26.43%), 34 patients reported somatosensory auras (14.97%), and 22 patients (9.69%) reported gustatory auras. A preoperative MRI finding of mesial temporal sclerosis (n = 135), comprised 49.09% of all cases and was significantly associated with epigastric auras (p < 0.01). Additionally, epigastric auras (p < 0.05) and a younger surgical age (p <0.05) were predictors of better Engel scores whereas gustatory auras (p < 0.05), a history of brain surgery (p < 0.05), and prior febrile seizures (p < 0.01) indicated worse outcomes. An MTS pathological finding was significantly associated with epigastric (p < 0.05), somatosensory auras (p < 0.05) and no auras (p < 0.05), whereas MTS negatively correlated with auditory auras (p < 0.01).
Conclusions: Our results indicate that auras contain valuable predictive information regarding not only the pathological foci specific to patients’ epilepsy, but also expected outcomes following surgical intervention. Physicians should consistently inquire about auras in order to optimize and individualize care to their patients.
Patient Care: As work elucidates the pathological mechanisms responsible for the presence of particular auras, physicians will be able to tailor their care to patients’ individual disease state. Our work establishes important relationships and defining features related to the pathological extent and predictive value of certain auras. The information uncovered in the study could guide physicians’ and patients’ decision making as it pertains to pursuing surgical intervention.
Learning Objectives: At the end of the session, participants should be able to: 1) Identify diagnostic factors that predict better outcomes following an anterior temporal lobectomy, 2) Discuss the pathological relevance related to particular auras, and 3) Utilize the information provided to the improve management of patients with medication refractory epilepsy.
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