Sexual orgasm as a trigger for reflex epilepsy.

Reflex epilepsy is a syndrome in which seizures can be elicited by a specific afferent sensory stimulus or an activity undertaken by the patient. Among all reported stimuli, orgasm has rarely been mentioned. We describe a woman presenting with seizures following orgasm. On interictal EEG, no epileptiform activity was found, even during hyperventilation. Brain MRI showed a small cyst next to the right choroid fissure, modulating the superior surface of the right hippocampus. We reviewed all published case reports of reflex epilepsy induced by orgasm in order to compare clinical, electroencephalographic and neuroimaging findings.

Musicogenic epilepsy in paraneoplastic limbic encephalitis: a video-EEG case report.

Musicogenic epilepsy (ME), a peculiar form of reflex epilepsy, represents a neurological rarity and yet another demonstration of the extraordinary power of music on the human brain. Despite the heterogeneity of the reported musical triggers, patients' emotional response to music is thought to play a crucial role in provoking seizures. Accordingly, the mesial temporal structures (especially of the non-dominant hemisphere) appear most involved in seizure generation, although a more complex fronto-temporal epileptogenic network was documented in some cases. Autoimmune encephalitis has been recently included among the many possible aetiologies of ME based on a few reports of music-induced seizures in patients with anti-glutamic acid decarboxylase 65 antibodies. Here, we describe the case of a 25-year-old man, educated in music over a long period of time, who had suffered from drug-resistant temporal lobe epilepsy following seronegative limbic encephalitis related to non-Hodgkin lymphoma. Along with spontaneous events, the patient also developed musicogenic seizures later in the disease course. After detecting five music-induced episodes via 24-hour ambulatory EEG, we performed prolonged video-EEG monitoring during which the patient presented a right temporal seizure (characterized by déjà-vu, piloerection and gustatory hallucinations) while listening to a hard rock song through headphones (which he had not previously heard). This observation allowed us to confirm the provoking effect of the music on our patient's seizures, despite the lack of any emotional drive, which suggests that a "cognitive" trigger was more likely in this case. Our report further highlights that autoimmune encephalitis should be investigated as a novel potential cause of musicogenic epilepsy, regardless of autoantibody status.

Symptomatic eating epilepsy: two novel pediatric patients and review of literature.

Eating epilepsy (EE) is a form of reflex epilepsy in which seizures are triggered by eating. It is a rare condition but a high prevalence has been reported in Sri Lanka. In EE, the ictal semiology includes focal seizures with or without secondary generalization or generalized seizures. Some cases are idiopathic while focal structural changes on imaging, if present, are often confined to the temporal lobe or perisylvian region. On the other hand, some cases support the hypothesis of a genetic aetiology. The prognosis of EE is extremely variable due to the different nature of the underlying disorder. We describe two patients with symptomatic eating epilepsy, a 13-year-old boy with a bilateral perisylvian polymicrogyria and a 2-year-old boy with a genetic cause. The presence of structural lesions or the dysfunction of specific cortical regions in the context of a germline genetic alteration might lead to a hyperexcitation fostering the epileptogenesis. We review the available literature to clarify the aetiopathogenesis and the mechanisms underlying EE to improve the diagnosis and the management of these rare conditions.

Epileptic seizures triggered by eating in dogs.

BACKGROUND: Seizures triggered by eating (STE) behavior are very rare in humans and have not been documented previously in dogs. OBJECTIVES: To document the occurrence of STE in dogs and describe their clinical features. ANIMALS: Ten client-owned dogs with STE diagnosed at 5 European referral centers. METHODS: A call for suspected cases of STE was made online. This call was followed by a retrospective review of medical records, combined with a questionnaire to be completed by both the owner and the board-certified neurologist who made the diagnosis. Cases were included if >50% of the seizures that occurred were related to eating and if a minimum diagnostic evaluation for seizures had been performed. RESULTS: Four cases only had STE and 6 cases had both STE and spontaneous seizures. Four of the dogs were retrievers. The most common seizure type was focal epileptic seizures evolving to become generalized. Nine dogs were diagnosed with idiopathic epilepsy. One dog had a presumptive diagnosis of glioma involving the margins of the parietal, temporal, and frontal cortex (the perisylvian region), an area known to have a key role in eating-associated epilepsy in people. Treatment strategies included a combination of pharmacological management and eating habit changes. CONCLUSIONS AND CLINICAL IMPORTANCE: We have identified a form of reflex epilepsy in dogs, with STE behavior. Further studies are warranted to improve the characterization and management of STE.

New-onset musicogenic epilepsy after temporal lobe epilepsy surgery.

Musicogenic epilepsy is a reflex epilepsy provoked by listening to or playing music. The epileptogenic network involves temporal regions, usually mesiotemporal structures. We present a 31-year-old female patient who experienced musicogenic seizures after a right temporal lobectomy with amygdalohippocampectomy that was performed in order to treat preexisting right mesio-temporal epilepsy.

[Rare cases of reflex epilepsy in patients with gliomas of the left hemisphere].

We present the cases of symptomatic reflex epilepsy in patients with left hemisphere tumors. The first case: a 23-year-old man has had tonic-clonic seizures of the tongue with rare secondary localization over the past several months. The seizures were caused by intense tongue movements, in particular rightward and leftward (when having chewing gum or a candy in his mouth), but not during speech production or eating. MRI scanning detected a small tumor in the lower segments of the central gyrus. It was found during the surgery under electrophysiological control that the tumor (Gr II astrocytoma) resided in the zone corresponding to the right half of the tongue and included this zone. The tumor was partially resected. The second patient, a 52-year-old man, has been suffering from generalized seizures since 1998. The seizures were caused by intense verbal load, in the beginning of spontaneous speech and subsequently when the patient was listening to others' speech or was writing. Spontaneous seizures emerged when the patient stopped taking his anti-seizure medications unilaterally. MRI showed glioma in the posterior segments of the left temporal lobe. The patient underwent radiation and chemotherapy. In 2013, the patient's condition worsened (right-sided hemiparesis and severe speech impairment emerged); the tumor was partially resected and an extensive cyst was opened. The third patient, a 38-year-old man with Gr III astrocytoma in the left insula with past medical history of spontaneous vegetative seizures, had only a seizure anticipation caused by strong smells. All the patients were prescribed chemo-, radiation, and anti-seizure therapy.

Reduced phenotypic severity following adeno-associated virus-mediated Fmr1 gene delivery in fragile X mice.

Fragile X syndrome (FXS) is a neurodevelopmental disorder caused by a trinucleotide repeat expansion in the FMR1 gene that codes for fragile X mental retardation protein (FMRP). To determine if FMRP expression in the central nervous system could reverse phenotypic deficits in the Fmr1 knockout (KO) mouse model of FXS, we used a single-stranded adeno-associated viral (AAV) vector with viral capsids from serotype 9 that contained a major isoform of FMRP. FMRP transgene expression was driven by the neuron-selective synapsin-1 promoter. The vector was delivered to the brain via a single bilateral intracerebroventricular injection into neonatal Fmr1 KO mice and transgene expression and behavioral assessments were conducted 22-26 or 50-56 days post injection. Western blotting and immunocytochemical analyses of AAV-FMRP-injected mice revealed FMRP expression in the striatum, hippocampus, retrosplenial cortex, and cingulate cortex. Cellular expression was selective for neurons and reached ∼ 50% of wild-type levels in the hippocampus and cortex at 56 days post injection. The pathologically elevated repetitive behavior and the deficit in social dominance behavior seen in phosphate-buffered saline-injected Fmr1 KO mice were reversed in AAV-FMRP-injected mice. These results provide the first proof of principle that gene therapy can correct specific behavioral abnormalities in the mouse model of FXS.

Reflex gelastic-dacrystic seizures following hypoxic-ischaemic encephalopathy.

Reflex or stimulus-sensitive epilepsies are uncommon epileptic syndromes triggered by exogenous-specific sensory stimulus or endogenous various mental activities. Gelastic-dacrystic seizures are rare epileptic manifestations characterised by ictal laughter and crying. Gelastic-dacrystic seizures are commonly caused by hypothalamic hamartoma but rarely described due to cortical dysplasia, lesions of frontal and temporal lobes, tumours and vascular malformations. We report a young woman who presented with somatosensory-evoked gelastic-dacrystic seizures. This patient had a positive history of perinatal insult substantiated by MRI findings. Hypoxic-ischaemic encephalopathy as the cause of gelastic-dacrystic seizures has not been reported so far in the literature.

Music and epilepsy: a critical review.

The effect of music on patients with epileptic seizures is complex and at present poorly understood. Clinical studies suggest that the processing of music within the human brain involves numerous cortical areas, extending beyond Heschl's gyrus and working within connected networks. These networks could be recruited during a seizure manifesting as musical phenomena. Similarly, if certain areas within the network are hyperexcitable, then there is a potential that particular sounds or certain music could act as epileptogenic triggers. This occurs in the case of musicogenic epilepsy, whereby seizures are triggered by music. Although it appears that this condition is rare, the exact prevalence is unknown, as often patients do not implicate music as an epileptogenic trigger and routine electroencephalography does not use sound in seizure provocation. Music therapy for refractory epilepsy remains controversial, and further research is needed to explore the potential anticonvulsant role of music. Dopaminergic system modulation and the ambivalent action of cognitive and sensory input in ictogenesis may provide possible theories for the dichotomous proconvulsant and anticonvulsant role of music in epilepsy. The effect of antiepileptic drugs and surgery on musicality should not be underestimated. Altered pitch perception in relation to carbamazepine is rare, but health care professionals should discuss this risk or consider alternative medication particularly if the patient is a professional musician or native-born Japanese. Studies observing the effect of epilepsy surgery on musicality suggest a risk with right temporal lobectomy, although the extent of this risk and correlation to size and area of resection need further delineation. This potential risk may bring into question whether tests on musical perception and memory should form part of the preoperative neuropsychological workup for patients embarking on surgery, particularly that of the right temporal lobe.

Early age conductive hearing loss causes audiogenic seizure and hyperacusis behavior.

Recent clinical reports found a high incidence of recurrent otitis media in children suffering hyperacusis, a marked intolerance to an otherwise ordinary environmental sound. However, it is unclear whether the conductive hearing loss caused by otitis media in early age will affect sound tolerance later in life. Thus, we have tested the effects of tympanic membrane (TM) damage at an early age on sound perception development in rats. Two weeks after the TM perforation, more than 80% of the rats showed audiogenic seizure (AGS) when exposed to loud sound (120 dB SPL white noise, < 1 min). The susceptibility of AGS lasted at least sixteen weeks after the TM damage, even the hearing loss recovered. The TM damaged rats also showed significantly enhanced acoustic startle responses compared to the rats without TM damage. These results suggest that early age conductive hearing loss may cause an impaired sound tolerance during development. In addition, the AGS can be suppressed by the treatment of vigabatrin, acute injections (250 mg/kg) or oral intakes (60 mg/kg/day for 7 days), an antiepileptic drug that inhibits the catabolism of GABA. c-Fos staining showed a strong staining in the inferior colliculus (IC) in the TM damaged rats, not in the control rats, after exposed to loud sound, indicating a hyper-excitability in the IC during AGS. These results indicate that early age conductive hearing loss can impair sound tolerance by reducing GABA inhibition in the IC, which may be related to hyperacusis seen in children with otitis media.

Unilateral opercular lesion and eating-induced seizures.

Eating-induced seizures are an uncommon presentation of reflex epilepsy, a condition characterized by seizures provoked by specific stimuli. Most reports have identified aetiology associated with malformations of cortical developmental, hypoxic brain injury, previous meningoencephalitis or static encephalopathy. We present a patient with eating-induced reflex seizures, which began several years after treatment for an opercular primitive neuroectodermal tumour (PNET), and who subsequently underwent in-depth clinical and video-EEG analysis for her seizures. This patient noted rapid improvement with decreased frequency of seizure activity after treatment with valproic acid. We discuss the aetiology of reflex epilepsy, the anatomical basis of eating-induced epilepsy, and review the current literature.

Electroclinical characterization of epileptic seizures in leucine-rich, glioma-inactivated 1-deficient mice.

Mutations of the LGI1 (leucine-rich, glioma-inactivated 1) gene underlie autosomal dominant lateral temporal lobe epilepsy, a focal idiopathic inherited epilepsy syndrome. The LGI1 gene encodes a protein secreted by neurons, one of the only non-ion channel genes implicated in idiopathic familial epilepsy. While mutations probably result in a loss of function, the role of LGI1 in the pathophysiology of epilepsy remains unclear. Here we generated a germline knockout mouse for LGI1 and examined spontaneous seizure characteristics, changes in threshold for induced seizures and hippocampal pathology. Frequent spontaneous seizures emerged in homozygous LGI1(-/-) mice during the second postnatal week. Properties of these spontaneous events were examined in a simultaneous video and intracranial electroencephalographic recording. Their mean duration was 120 +/- 12 s, and behavioural correlates consisted of an initial immobility, automatisms, sometimes followed by wild running and tonic and/or clonic movements. Electroencephalographic monitoring indicated that seizures originated earlier in the hippocampus than in the cortex. LGI1(-/-) mice did not survive beyond postnatal day 20, probably due to seizures and failure to feed. While no major developmental abnormalities were observed, after recurrent seizures we detected neuronal loss, mossy fibre sprouting, astrocyte reactivity and granule cell dispersion in the hippocampus of LGI1(-/-) mice. In contrast, heterozygous LGI1(+/-) littermates displayed no spontaneous behavioural epileptic seizures, but auditory stimuli induced seizures at a lower threshold, reflecting the human pathology of sound-triggered seizures in some patients. We conclude that LGI1(+/-) and LGI1(-/-) mice may provide useful models for lateral temporal lobe epilepsy, and more generally idiopathic focal epilepsy.

Potential of wind turbines to elicit seizures under various meteorological conditions.

PURPOSE: To determine the potential risk of epileptic seizures from wind turbine shadow flicker under various meteorologic conditions. METHODS: We extend a previous model to include attenuation of sunlight by the atmosphere using the libradtran radiative transfer code. RESULTS: Under conditions in which observers look toward the horizon with their eyes open we find that there is risk when the observer is closer than 1.2 times the total turbine height when on land, and 2.8 times the total turbine height in marine environments, the risk limited by the size of the image of the sun's disc on the retina. When looking at the ground, where the shadow of the blade is cast, observers are at risk only when at a distance <36 times the blade width, the risk limited by image contrast. If the observer views the horizon and closes their eyes, however, the stimulus size and contrast ratio are epileptogenic for solar elevation angles down to approximately 5 degrees. DISCUSSION: Large turbines rotate at a rate below that at which the flicker is likely to present a risk, although there is a risk from smaller turbines that interrupt sunlight more than three times per second. For the scenarios considered, we find the risk is negligible at a distance more than about nine times the maximum height reached by the turbine blade, a distance similar to that in guidance from the United Kingdom planning authorities.

Kinesigenic reflex epilepsy associated with a glioma in the lateral peri-rolandic region.

A patient with kinesigenic focal motor seizures induced by tongue-jaw movement had a grade III astrocytoma clearly co-localizing with the epileptic network in the appropriate peri-rolandic, motor-sensory, lingual-jaw cortical area. The clinical seizure phenomena were time-locked with the EEG epileptic activity. [Published with video sequences].

The expression of glutamate transporters in chest compression-induced audiogenic epilepsy: a comparative study.

BACKGROUND: This study was conducted to compare the expression of three glutamate transporter subtypes (GLAST, GLT-1 and EAAC1) in rats undergoing chest compression-induced global cerebral ischemia in the presence and absence of cerebral ischemia-related epilepsy. MATERIAL AND METHODS: A reliable rat model of global cerebral ischemia-related epilepsy was established. The rats were divided into the following groups: sham surgery group (Group S), global cerebral ischemia without epilepsy (Group I) and global cerebral ischemia with epilepsy (Group E). The latter two groups were further divided into four subgroups based on time (24 hours, 72 hours, 5 days and 7 days) after 8 minutes of chest compression. Electroencephalographic recordings were obtained in all rats. Hippocampal tissue samples were prepared, and the expression of GLAST, GLT-1 and EAAC1 in the hippocampal CA1 region and the motor cortex area was studied using immunohistochemical methods. RESULTS: Seizure developed in 32 (64%) of 50 rats. Compared with that in group I, the expression of GLT-1 in the hippocampal CA1 region and the motor cortex area in group E was down-regulated, and EAAC1 was up-regulated in those regions. CONCLUSION: Altering the expression of GLT-1 and EAAC1 through some means might lead them to be potential targets for therapy in cerebral ischemia-related epilepsy.

Transcranial imaging of audiogenic epileptic foci in the cortex of DBA/2J mice.

Exposure to intense sound stimuli induces audiogenic seizures in DBA/2J mice. We investigated cortical activities during sound stimulation using flavoprotein fluorescence imaging. Most DBA/2J mice had seizures during intense sound stimulation, with more than half surviving after seizures. Surviving mice were anesthetized with urethane (1.6 g/kg, intraperitoneal), and the skull was exposed and then covered with clear resin. More than 3 days after surgery, the mice were lightly anesthetized with urethane (0.8 g/kg) and cortical activities during intense sound stimulation were visualized. Focal responses appeared near the somatosensory cortex together with spike activities localized in the response area. These findings indicate that epileptic foci of audiogenic seizure are formed in the cortex of DBA/2J mice.