Differences in visual information processing style between Idiopathic Generalized Epilepsy with and without photosensitivity.

PURPOSE: Recently, altered visual cortical processes i.e., lack of habituation to visual evoked potentials (VEP), has been highlighted in both photosensitive epilepsy and in a specific i.e., analytic mode of processing visual inputs. In this study we aimed at evaluating the relationship between photosensitivity (PS) and analytic style of processing visual information, in a sample of 30 patients with Idiopathic Generalized Epilepsy (IGE) and matched healthy controls. METHODS: At our Epilepsy unit of the Sapienza University of Rome, we consecutively enrolled 15 patients with IGE with PSand matched them with 15 patients with IGE without PS and 15 Healthy Volunteers. All patients underwent EEG recording in basal conditions during hyperventilation (3 Min), and intermittent light stimulation. The most effective frequencies comprised from 12 to 16 Hz. The instruments used to gather psychological cognitive behavioral data, consisted of participation in two tests: the Sternberg-Wagner Self-Assessment Inventory and the Mariani Learning Style Questionnaire. RESULTS: Compared to controls, both IGE groups show significantly higher scores for the analytic style (One-way ANOVA, F(2,44) = 110.3, p < 0.0001). Epilepsy groups thereby showed very distinctive cognitive styles as measured with the Sternberg test. In the visual style, scores of the photosensitive Individuals with IGE were significantly higher than the non-photosensitive individuals with IGE (p < 0.0001, Tukey's post hoc test). CONCLUSIONS: An association between analytic style of processing visual information and PS in IGE has been shown. The common neurophysiological features between these two factors, suggest the possibility to evaluate this cognitive behavior as a potential target for nonpharmacological therapeutic strategies in photosensitive epilepsy.

Doing without valproate in women of childbearing potential with idiopathic generalized epilepsy: Implications on seizure outcome.

OBJECTIVE: Valproate (VPA) use in women with idiopathic generalized epilepsy (IGE) who are of reproductive age has been a matter of concern and debate, which eventually led to the recent restrictions by regulatory agencies. The aim of our study was to investigate the relationship between VPA avoidance/switch and seizure outcome in women of childbearing potential. METHODS: We retrospectively reviewed data from female patients with IGE, 13-50 years of age, followed since 1980. We evaluated the prescription habits, and the rate of VPA switch for other antiepileptic drugs (AEDs) and its prognostic implications. Seizure remission (SR) was defined as the absence of any seizure type more than 18 months before the last medical observation. The main aim of the study was to assess (a) possible changes in seizure outcome related to VPA switch for other AEDs, especially in patients planning a pregnancy; and (b) possible differences in SR based on the presence/absence of VPA at last observation. RESULTS: One hundred ninety-eight patients were included in the study. Overall SR at last medical observation was 62.7%. SR significantly differed between subjects taking and those not taking VPA (P < .001) at last visit. Multiple regression models showed that taking VPA at last medical observation was strongly associated with SR in both the general population (P < .001) and the juvenile myoclonic epilepsy (JME) group (P < .001). Thirty-six (70.6%) of 51 patients who switched from VPA during follow-up experienced a clinical worsening. Switching back to VPA was more frequently associated with SR at last observation (P < .001). In those patients who substituted VPA in view of a pregnancy, SR and drug burden (monotherapy vs polytherapy) differed significantly before and after the switch. SIGNIFICANCE: Our study suggests that VPA avoidance/switch might be associated with unsatisfactory seizure control in women with IGE who are of childbearing potential. Our findings further highlight the complexity of the therapeutic management of female patients of reproductive age.

Anxiety as the only manifestation of focal non-convulsive status epilepticus: case report and review of the literature.

Psychiatric disorders represent common comorbidities in epileptic patients. Sometimes anxiety is part of the ictal semiology, especially during seizures arising from/involving frontal or temporal lobes. We describe a patient with focal epilepsy and recurrent hyperkinetic seizures who also presented prolonged episodes characterized by massive anxiety, alarm and fear. A Video-Electroencephalographic monitoring performed during one of these attacks revealed a continuous epileptiform activity over the right frontal regions, consistent with a focal non-convulsive status epilepticus accounting for the patient's psychiatric symptoms. Our case confirms the complex relationship between epilepsy and anxiety. A review of the literature is also included.

Analytic information processing style in epilepsy patients.

Relevant to the study of epileptogenesis is learning processing, given the pivotal role that neuroplasticity assumes in both mechanisms. Recently, evoked potential analyses showed a link between analytic cognitive style and altered neural excitability in both migraine and healthy subjects, regardless of cognitive impairment or psychological disorders. In this study we evaluated analytic/global and visual/auditory perceptual dimensions of cognitive style in patients with epilepsy. Twenty-five cryptogenic temporal lobe epilepsy (TLE) patients matched with 25 idiopathic generalized epilepsy (IGE) sufferers and 25 healthy volunteers were recruited and participated in three cognitive style tests: "Sternberg-Wagner Self-Assessment Inventory", the C. Cornoldi test series called AMOS, and the Mariani Learning style Questionnaire. Our results demonstrate a significant association between analytic cognitive style and both IGE and TLE and respectively a predominant auditory and visual analytic style (ANOVA: p values <0,0001). These findings should encourage further research to investigate information processing style and its neurophysiological correlates in epilepsy.

Ictal EEG/fMRI study of vertiginous seizures.

Vertigo and dizziness are extremely common complaints, related to either peripheral or central nervous system disorders. Among the latter, epilepsy has to be taken into consideration: indeed, vertigo may be part of the initial aura of a focal epileptic seizure in association with other signs/symptoms, or represent the only ictal manifestation, a rare phenomenon known as "vertiginous" or "vestibular" seizure. These ictal symptoms are usually related to a discharge arising from/involving temporal or parietal areas, which are supposed to be a crucial component of the so-called "vestibular cortex". In this paper, we describe three patients suffering from drug-resistant focal epilepsy, symptomatic of malformations of cortical development or perinatal hypoxic/ischemic lesions located in the posterior regions, who presented clusters of vertiginous seizures. The high recurrence rate of such events, recorded during video-EEG monitoring sessions, offered the opportunity to perform an ictal EEG/fMRI study to identify seizure-related hemodynamic changes. The ictal EEG/fMRI revealed the main activation clusters in the temporo-parieto-occipital regions, which are widely recognized to be involved in the processing of vestibular information. Interestingly, ictal deactivation was also detected in the ipsilateral cerebellar hemisphere, suggesting the ictal involvement of cortical-subcortical structures known to be part of the vestibular integration network.

Ictal pain in focal non-convulsive status epilepticus.

We report an adult with acute unilateral pain as isolated manifestation of acute symptomatic focal non-convulsive status epilepticus. Pain is rarely a manifestation of epileptic seizures. Traditionally, painful seizures have been thought to originate in either the parietal or temporal lobes, but their localising value is debatable. Recent functional neuroimaging studies and electrophysiological findings obtained by using intracerebral recordings have shown the involvement of the insular cortex along with several other brain structures in the processing of painful inputs, comprising a more widespread anatomo-functional network. Despite their rarity as a distinct clinical entity, especially in adults, painful somatosensory seizures can be disabling and misdiagnosis or delayed diagnosis is common; it is therefore essential to consider epilepsy as a possible cause of paroxysmal pain to ensure proper assessment and appropriate treatment.

Ictal epileptic headache in adult life: Electroclinical patterns and spectrum of related syndromes.

OBJECTIVES: Both headache and epilepsy are frequent paroxysmal disorders that often co-occur or are related in numerous ways. Although ictal epileptic headache has become the focus of several studies, this remains a very rare and not well-known phenomenon. Electroclinical features, pathophysiology, and syndromic context are heterogeneous. We investigated the electroclinical and neuroimaging findings in a population of adult patients with ictal epileptic headache. METHODS: We retrospectively examined 8800 EEG recordings of almost 4800 patients admitted to our video-EEG laboratory from 2010 to 2013 with a history of well-documented epilepsy. We selected patients who reported headache closely related to a seizure documented by video-EEG or 24-hour ambulatory EEG. We analyzed ictal electroclinical features of headache, and we defined the related epileptic syndromes. RESULTS: We identified five patients with ictal epileptic headache. Two patients described tension headache during an epileptic seizure. In three patients, the headache was accompanied by other "minor" neurological symptoms mimicking a migrainous aura. In all cases, the headache stopped with the end of the epileptic activity. Three patients had a history of partial symptomatic epilepsy with cerebral lesions (low grade glioma, astrocytoma, porencephalic cyst) in the left posterior regions, whereas two patients were affected by idiopathic generalized epilepsy. CONCLUSION: This study confirms the rarity of ictal epileptic headache. To date, well-documented video-EEG cases remain as exceptional reports, especially in cases of idiopathic generalized epilepsies. Moreover, we confirm the main involvement of posterior regions in patients with ictal epileptic headache affected by partial symptomatic epilepsies.

Cryptogenic focal epilepsy and "hidden" celiac disease in adulthood: a causal or accidental link?

PURPOSE: Celiac disease (CD) is an immuno-mediated small bowel disease characterized by chronic inflammation due to a permanent intolerance to gliadin. Several neurological complications have been described, including epilepsy, whose evolution might often improve by adopting gluten-free diet (GFD). We studied a population of adult patients affected by posterior drug-resistant epilepsy of unknown cause by performing an accurate screening for CD. In the selected patients presenting the association of epilepsy and CD, we characterized the related electro-clinical features. MATERIALS AND METHODS: We consecutively identified 211 adult subjects affected by drug-resistant cryptogenic focal epilepsy with posterior seizures. All these patients underwent serological screening for CD. In 10 subjects positive serological tests allowed to perform a CD diagnosis (confirmed by duodenal biopsy). For each patient clinical and EEG data, neuroimaging studies, serological and histological findings were revised, as well as response to GFD, defined as an improvement in seizure outcome. RESULTS: A significant delay between diagnosis of epilepsy and CD was documented. Visual ictal manifestations were reported in half of subjects. In all cases, interictal EEG showed slow and epileptiform abnormalities over parietal-occipital and temporal regions; in three cases, FOS phenomenon was observed. Four patients had familiar history of CD and six cases showed clinical signs/symptoms of malabsorption. GFD led to a reduction of seizure frequency in half of patients. CONCLUSIONS: "Posterior" ictal semiology, peculiar EEG patterns and drug-resistance emerge as the most interesting characteristics. CD screening should be performed in epilepsy patients presenting such features.

Ictal epileptic headache revealing non convulsive status epilepticus in a case of eyelid myoclonia with absences.

Epileptic seizures and headache attacks are two common neurologic phenomena characterized by paroxysmal alteration of brain functions followed by complete restauration of the baseline condition. Headache and epilepsy are related in numerous ways, and they often co-occur. Although the link between these two diseases is not completely clear, several clinical, physiopathological and therapeutic features overlap. Headache is reported in association with epileptic seizures as a pre-ictal, ictal or post-ictal phenomenon. We present the case of a 40 year-old woman affected by eyelid myoclonia with absences (EMA) with a history of prolonged headache attacks. A video-EEG recording performed during one of these episodes showed subcontinuous epileptic activity consisting of generalized spike-and-wave discharges (GSWDs), clinically associated with tensive headache. Our work represents one of the few well EEG-documented cases of ictal epileptic headache in idiopathic generalized epilepsy (IGE).

Functional Gastrointestinal Disorders in Patients With Epilepsy: Reciprocal Influence and Impact on Seizure Occurrence.

Introduction: The complex relationship between the microbiota-gut-brain axis (MGBA) and epilepsy has been increasingly investigated in preclinical studies. Conversely, evidence from clinical studies is still scarce. In recent years, the pivotal role of MGBA dysregulation in the pathophysiology of functional gastrointestinal disorders (FGID) has been recognized. With this background, we aimed to investigate the prevalence of FGID in patients with epilepsy (PWE) and the possible impact of bowel movement abnormalities on seizure recurrence. Methods: A total of 120 PWE and 113 age-, sex-, and BMI-matched healthy subjects (HS) were consecutively enrolled. A questionnaire to evaluate the presence of FGID (according to Rome III diagnostic criteria) was administrated to all participants. In a subgroup of drug-resistant patients, we administered an ad-hoc questionnaire combining Bristol stool charts and seizure diaries to evaluate seizure trends and bowel movement changes. Results: A higher prevalence of FGID in PWE (62.5%) than in HS (39.8%) was found (p < 0.001). The most frequently observed disorder was constipation, which was significantly higher in PWE than in HS (43.3 vs. 21.2%, p < 0.001), and was not associated with anti-seizure medication intake according to multivariable analysis. In drug-resistant patients, most seizures occurred during periods of altered bowel movements, especially constipation. A significant weak negative correlation between the number of days with seizures and the number of days with normal bowel movements was observed (p = 0.04). According to multivariable logistic regression analysis, FGID was significantly associated with temporal lobe epilepsy as compared with other lobar localization (p = 0.03). Conclusions: Our clinical findings shed new light on the complex relationship between epilepsy and the MGBA, suggesting a bidirectional link between bowel movement abnormalities and seizure occurrence. However, larger studies are required to better address this important topic.

Cannabinoids in the Treatment of Epilepsy: Current Status and Future Prospects.

Cannabidiol (CBD) is one of the prominent phytocannabinoids found in Cannabis sativa, differentiating from Δ9-tetrahydrocannabinol (THC) for its non-intoxicating profile and its antianxiety/antipsychotic effects. CBD is a multi-target drug whose anti-convulsant properties are supposed to be independent of endocannabinoid receptor CB1 and might be related to several underlying mechanisms, such as antagonism on the orphan GPR55 receptor, regulation of adenosine tone, activation of 5HT1A receptors and modulation of calcium intracellular levels. CBD is a lipophilic compound with low oral bioavailability (6%) due to poor intestinal absorption and high first-pass metabolism. Its exposure parameters are greatly influenced by feeding status (ie, high fat-containing meals). It is mainly metabolized by cytochrome P 450 (CYP) 3A4 and 2C19, which it strongly inhibits. A proprietary formulation of highly purified, plant-derived CBD has been recently licensed as an adjunctive treatment for Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS), while it is being currently investigated in tuberous sclerosis complex. The regulatory agencies' approval was granted based on four pivotal double-blind, placebo-controlled, randomized clinical trials (RCTs) on overall 154 DS patients and 396 LGS ones, receiving CBD 10 or 20 mg/kg/day BID as active treatment. The primary endpoint (reduction in monthly seizure frequency) was met by both CBD doses. Most patients reported adverse events (AEs), generally from mild to moderate and transient, which mainly consisted of somnolence, sedation, decreased appetite, diarrhea and elevation in aminotransferase levels, the last being documented only in subjects on concomitant valproate therapy. The interaction between CBD and clobazam, likely due to CYP2C19 inhibition, might contribute to some AEs, especially somnolence, but also to CBD clinical effectiveness. Cannabidivarin (CBDV), the propyl analogue of CBD, showed anti-convulsant properties in pre-clinical studies, but a plant-derived, purified proprietary formulation of CBDV recently failed the Phase II RCT in patients with uncontrolled focal seizures.

Seizures in autoimmune encephalitis: Findings from an EEG pooled analysis.

PURPOSE: Seizures are common in autoimmune encephalitis (AE), and an extensive work-up is required to exclude alternative etiologies. The aim of our study was to identify possible clinical/EEG peculiarities suggesting the immune-mediated origin of late-onset seizures. METHODS: Thirty patients diagnosed with AE (19 men, median age 68 years, 18 seronegative) were included. Overall 212 video-electroencephalographic (EEG) and 31 24-h ambulatory EEG (AEEG) recordings were retrospectively reviewed. Posterior dominant rhythm, interictal epileptiform discharges (IEDs), clinical (CSs) and subclinical seizures (SCSs) were analyzed. RESULTS: Six-hundred-nineteen ictal events were recorded in 19/30 subjects, mostly (568/619) during AE acute stage. Among ten patients with CSs other than faciobrachial dystonic seizures, 7 showed prominent autonomic and emotional manifestations. SCSs were detected in 11 subjects, mainly via AEEG (260/287 SCSs vs 150/332 CSs, p < 0.001). Eight patients presented seizures during hyperventilation. IEDs, documented in 21 cases, were bilateral in 14 and focal temporal in 13. Multiple ictal EEG patterns were detected in 9/19 patients, 6 of whom had both CSs and SCSs, bilateral asynchronous seizures and ictal activities arising from temporal and extra-temporal regions. No correlation was found between the lateralization of MRI alterations and that of EEG findings. CONCLUSION: Our study confirms that adult-onset, high frequency focal seizures with prominent autonomic and emotional manifestations should be investigated for AE. Multiple ictal EEG patterns could represent a 'red flag', reflecting a widespread neuronal excitability related to the underlying immune-mediated process. Finally, our work enhances the crucial role of long-lasting EEG monitoring in revealing subclinical and relapsing seizures.

Valproate impact and sex-dependent seizure remission in patients with idiopathic generalized epilepsy.

BACKGROUND: Idiopathic Generalized Epilepsy (IGE) management has become increasingly challenging due to the restricted use of Valproate (VPA) in females. The aim of the study was to assess possible differences in terms of seizure outcome between men and women suffering from IGE. METHODS: A cohort of IGE patients (age range: 13-50 years) followed from 1980 to 2018 were included. Their medical history was retrospectively reviewed to investigate possible factors influencing seizure outcome. Seizure Remission (SR) was defined as the absence of any seizure type over 18 months prior to the last medical observation. The primary outcome was to evaluate sex differences in terms of SR at last observation. A multivariable logistic regression model was elaborated using SR as dependent variable. RESULTS: Three-hundred and sixty patients were included, 204 (56.7%) of whom were women. The median age at the end of follow-up was 30. At last medical observation, fewer women were receiving VPA compared with men (females 39.7% vs males 79.5%, p < .001). Overall SR was 70.6%. SR was significantly different according to sex (females 62.3% vs males 81.4%, p < .001). Multivariable logistic regression model showed that female sex (Odds Ratios [OR] = 0.52, 95% Confidence Interval [CI] = 0.29-0.94; p = .03), VPA treatment at last observation (OR = 0.44, 95% CI = 0.25-0.76; p = .003) and epilepsy syndrome (p < .001) were the factors independently associated with SR. CONCLUSIONS: Recent modifications in VPA prescribing patterns may have determined a worse seizure control among IGE female patients. Comparative clinical trials assessing the best therapeutic options for women with childbearing potential are urgently needed.

Ictal atrial fibrillation during focal seizures: a case report and literature review.

Cardiac arrhythmias are a common but often overlooked symptom that occur during or after epileptic seizures. The characterization of seizure-related heart rhythm disorders could shed light on the functional organization of the so-called "central autonomic network" and possibly on the pathophysiology of sudden death of epilepsy patients (SUDEP). Indeed, epileptic discharges may affect the heart through the involvement of cortical regions selectively driving autonomic functions. Ictal atrial fibrillation is an exceedingly rare phenomenon, usually associated with generalized tonic-clonic seizures. Here, we report a case of paroxysmal atrial fibrillation as a core presenting feature of a focal non-motor seizure in a 68-year-old man, at first misdiagnosed and treated for a typical cardiogenic arrhythmia. A brief literature review is included.

Factors underlying the development of chronic temporal lobe epilepsy in autoimmune encephalitis.

PURPOSE: Limbic encephalitis (LE) is an autoimmune condition characterized by amnestic syndrome, psychiatric features and seizures. Early diagnosis and prompt treatment are crucial to avoid long-term sequelae, including psycho-cognitive deficits and persisting seizures. The aim of our study was to analyze the characteristics of 33 LE patients in order to identify possible prognostic factors associated with the development of chronic epilepsy. METHODS: This is a retrospective cohort study including adult patients diagnosed with LE in the period 2010-2017 and followed up for ≥12 months. Demographics, seizure semiology, EEG pattern, MRI features, CSF/serum findings were reviewed. RESULTS: All 33 LE patients (19 M/14F, mean age 61.2 years) presented seizures. Thirty subjects had memory deficits; 22 presented behavioural/mood disorders. Serum and/or CSF auto-antibodies were detected in 12 patients. In 31 subjects brain MRI at onset showed typical alterations involving temporal lobes. All patients received immunotherapy. At follow-up, 13/33 had developed chronic epilepsy; predisposing factors included delay in diagnosis (p = .009), low seizure frequency at onset (p = .02), absence of amnestic syndrome (p = .02) and absence/rarity of inter-ictal epileptic discharges on EEG (p = .06). CONCLUSIONS: LE with paucisymptomatic electro-clinical presentation seemed to be associated to chronic epilepsy more than LE presenting with definite and severe "limbic syndrome".

Perampanel as adjunctive therapy in highly refractory epilepsies: Real-world data from an Italian tertiary care epilepsy centre.

Perampanel (PER) is a selective non-competitive α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor antagonist, licensed as adjunctive therapy in focal epilepsy and primary generalized tonic-clonic seizures (pGTCSs). We performed a retrospective study on highly refractory adult patients taking PER, with 1-year follow-up. Retention rate represented the primary outcome of our work; seizure frequency reduction (≥50%), "switch rate" and proportion of adverse events (AEs) were evaluated as secondary endpoints. Eighty-nine subjects (47 females, age range: 19-78 years) were included. Seventy-three had focal epilepsy (FE), 9 generalized epilepsy and 7 epileptic encephalopathy. All patients were highly drug-resistant (medication failures: 5-17). Retention rate was 87.6%, 63% and 51.7% at 3, 6 and 12 months. Responders were 27/89 (30.3%), with 8/27 seizure-free. The number of previous treatment failures and the concomitant use of enzyme inducers negatively influenced clinical response, whereas no correlation was documented between PER dose and outcome. Responder proportion was more satisfying in structural FE than in FE of unknown etiology (33% versus 20%), and in secondarily GTCSs than focal seizures (54% vs 28%), whereas pGTCSs showed a lower reponse rate (25%). Mild-to-moderate AEs (mainly dizziness, gait disturbances and psychiatric effects) were reported by 40% of patients; serious psychiatric AEs usually occurred in subjects with psychiatric comorbidities. Our study confirms the tolerability and effectiveness of PER in highly drug-resistant patients with different epilepsy syndromes and aetiologies.

Switch From Originator to Equivalent Drug in the Era of Generic Antiepileptic Drugs: Study of Keppra Versus Epitiram Clinical Equivalence.

OBJECTIVES: Generic antiepileptic drugs represent a measure to maximize cost saving. Levetiracetam (LEV) is one of most commonly used and effective antiepileptic drugs. The objective of our work was to demonstrate the effectiveness and safety of overnight switch from monotherapy with Keppra (original drug) to epitiram (generic drug) at the same dose. METHODS: In our observational study, we consecutively enrolled 37 seizure-free patients with epilepsy who expressed the wish to switch to a generic drug for economic reasons. During the 6-month evaluation period, we assessed treatment efficacy, tolerability, compliance, and intersubject variability of LEV serum concentration. At each visit, clinical and neurological examination, scales, video-electroencephalogram, and blood sample analysis to evaluate LEV plasma level were performed. RESULTS: A total of 36 of 37 enrolled patients switched from Keppra to epitiram, which was administered at the same dose in monotherapy. Three of 36 patients dropped out during follow-up for adverse events. The other 33 subjects had neither seizures nor adverse events. No significant differences in electroencephalogram features and scale scores were revealed; the intersubject variability of LEV serum concentration did not differ significantly at follow-up evaluation (P = 0.53). All the patients expressed good clinical personal impression and continued to take epitiram. The switchback rate was 8 %. CONCLUSIONS: The switch from Keppra to epitiram was easy and safe in our population, and epitiram can be considered as effective and tolerable as Keppra. Only a slight, non-statistically significant variability in LEV serum concentration was documented after the switch from Keppra to epitiram. Larger epileptic populations should be studied to confirm these results.

Epileptic seizures heralding a relapse in high grade gliomas.

PURPOSE: Seizures are a common clinical symptom in high-grade gliomas (HGG). The aim of the study was to investigate the relationship between seizures and HGG relapse (HGG-R). METHODS: We retrospectively evaluated 145 patients who were surgically treated for HGG-R. By analyzing clinical characteristics in these patients (all operated and treated by the same protocol), we identified 37 patients with seizures during follow-up. This cohort was divided into four subgroups according to a) presence or absence of seizures at the time of diagnosis and b) temporal relationship between seizure occurrence and HGG-R during follow-up: subgroup A (25pts) had seizures at follow-up but not at onset, subgroup B (12pts) had seizures both at follow-up and onset, subgroup C (30pts) had seizures before MRI-documented HGG-R, and subgroup D (7pts) had seizures after MRI-documented HGG-R. RESULTS: Although the datum was not statistically significant, survival was longer in patients with seizures during follow-up than in those without seizures (59.3% vs 51.4% alive at 2 years). In 30 patients (subgroup C) seizures heralded HGG-R. In a correlation analysis for this last subgroup, the time interval between seizure and the HGG-R was significantly associated with the number of chemotherapy cycles (r=0.470; p=0.009) and follow-up duration (r=0.566; p=0.001). A linear regression model demonstrated a reciprocal association between the above factors and that it may be possible to estimate the timing of HGG-R by combining these data. CONCLUSIONS: Seizures may herald HGG-R before MRI detection of relapse, thus suggesting that seizures should always be considered a red flag during follow-up.