Functional neurological seizures and migraine: A systematic review and case series.

BACKGROUND: The seizure subtype of functional neurological disorder (FND-seizures) is a common neuropsychiatric condition manifesting with episodic epilepsy-like events. Despite the common belief that FND-seizures are precipitated by psychological stressors, neurological disorders may also be triggers. In 1890, Babinski described four cases of FND symptoms associated with migraine attacks. Despite the passing of more than 130 years since this first clinical observation, the relationship between FND-seizures and migraine is not fully elucidated. OBJECTIVES: (1) To complete a systematic review of the literature that investigated potential associations between FND-seizures and migraine and the response of FND seizures to treatment with migraine prophylactic medications (2). To undertake a retrospective study of patients with FND-seizures and migraine, including response to migraine prophylaxis. METHODS: (1) Using PRISMA methods, we completed a systematic review of EMBASE and Scopus databases from inception to March 31, 2021, for literature on FND-seizures and migraine. (2) Our multi-disciplinary team, including subspecialists in psychosomatic medicine, epilepsy, and headache disorders, reviewed consecutive patients diagnosed with FND-seizures and migraine to assess potential causal associations and responses to standard migraine prophylactic medications. RESULTS: (1) The search yielded seven studies from 126 screened manuscripts (N = 1,186 patients with FND-seizures; mean age 38.7 years; 72.6% female). They varied substantially in design, population, diagnostic measures, and outcomes. Nevertheless, all studies found associations between FND-seizures and migraine, which were stronger than those between epileptic seizures and migraine in comparative investigations, but provided limited information on treatment response. (2) In our case series, investigators reached unanimous consensus that migraine attacks triggered FND-seizures in 28/43 (65.1%) patients reviewed (mean age, 38.8 years; 74% female). In 19/26 (73%) patients with adequate follow-up data, treatment with migraine prophylactic medications alone (no behavioral interventions) concomitantly reduced FND-seizure and headache frequency by >50%. CONCLUSION: Our systematic review and case series indicate that migraine attacks may trigger FND-seizures, perhaps more often that currently understood, and suggest that migraine prophylaxis may reduce FND-seizure frequency in such cases. To validate these observations, fully powered prospective investigations are required.

When drugs and surgery don't work.

Epilepsy is a chronic disorder characterized by recurrent and unprovoked seizures (Dreifuss, 1987; Hauser & Hesdorffer, 1990). It is one of the most common neurologic disorders in the adult. The lifetime risk of developing epilepsy is 3.2% (Mattson, 1992). Approximately 90% of the incident cases in adults have symptomatic partial or localization-related epilepsy (Camfield & Camfield, 1996; Hauser & Hesdorffer, 1990; Hauser, 1992). The medial temporal lobe is the most epileptogenic region of the brain (Luby et al., 1995; Jeong et al., 1999; Wiebe et al., 2001). Pathologic lesions underlying the epileptogenic zone include mesial temporal sclerosis (MTS), tumor, vascular anomaly, malformations of cortical development (MCDs), and head trauma (Cascino et al., 1993; Radhakrishnan et al., 1998). The initial response to medication is of prognostic importance (Hauser, 1992). Patients with a remote symptomatic neurologic disease, foreign-tissue lesion, developmental delay, or abnormal neurologic examination are less likely to be rendered seizure-free. The goals of treatment are to render the individual seizure-free without producing antiepileptic drug (AED) toxicity, allowing the individual to become a participating and productive member of society (Engel & Ojemann, 1993). Despite the introduction of "newer" AEDs, nearly one-half of patients with partial epilepsy will not attain a seizure remission with pharmacotherapy (Kwan & Brodie, 2003). This discussion focuses on management of the adult patient with intractable partial seizure disorders that are medically refractory and may not be surgically remediable. It is estimated that 400,000 of the 2 million individuals with partial epilepsy in the United States have a medically refractory partial seizure disorder (Hauser & Hesdorffer, 1990; Hauser, 1992). An estimated 1,500 patients in the United States undergo epilepsy surgery each year. A UK study indicated that 30,000 patients develop epilepsy each year and approximately 6,000 have medically refractory seizures (Lhatoo et al., 2003). However, there are only about 400 epilepsy surgeries performed annually in the UK. Therefore, the number of patients with intractable partial epilepsy that is both medically refractory and possibly not a surgically remediable epileptic syndrome is significant.

Influence of subtraction ictal SPECT on surgical management in focal epilepsy of indeterminate localization: a prospective study.

The impact of functional imaging tests on the decision-making and planning process for epilepsy surgery has never been prospectively assessed. We prospectively evaluated 50 consecutively eligible patients whose noninvasive evaluations showed nonlocalized findings and determined how their SISCOM (subtraction ictal SPECT [single photon emission computed tomography] co-registered to MRI [magnetic resonance imaging]) data altered consensus decisions for epilepsy surgery. At an epilepsy surgery conference where each patient was discussed, consensus decisions were documented after a standardized presentation of data from the noninvasive evaluation (SISCOM findings initially were excluded). Consensus decisions were again documented after presentation of SISCOM data. Consensus decisions changed for 10 of 32 patients (31%) with localizing SISCOM results, whereas the decision changed in only 1 of 18 patients (6%) with nonlocalizing SISCOM results (P<.05). Changes in consensus decisions were as follows: (1) intracranial electrode implantation (IEI) was obviated and resective surgery was recommended (n=2); (2) resective surgery or further evaluation for patients initially not considered surgical candidates (n=2); (3) IEI in patients for whom it was not recommended initially (n=3); (4) increased IEI coverage (n=3); and (5) antiepileptic drug trial or vagal nerve stimulation was recommended instead of IEI (n=1). For some patients whose noninvasive evaluations did not clearly localize a surgical focus, SISCOM data can have a major impact on decisions to recommend resective epilepsy surgery or IEI.