Usefulness of ocular compression during electroencephalography in distinguishing breath-holding spells and syncope from epileptic seizures

Episodes of syncope or breath-holding spells are often misdiagnosed as epileptic events. The purpose of this study was to assess the usefulness of an electroencephalogram (EEG) with ocular compression to distinguish breath-holding spells and syncope from epileptic seizures. A retrospective analysis was performed on the EEG records of all children on whom ocular compression was performed from 2000 to 2003. Data from 116 patients with a clinical diagnosis consistent with either syncope or breath-holding spells were compared with a group of 46 patients with epilepsy. The RR interval during ocular compression was significantly higher in syncope patients compared with patients with epilepsy (P < .005). Using 2 seconds of asystole as the cutoff, the sensitivity of ocular compression was 26%, with 100% specificity. The change in RR interval from baseline to ocular compression also distinguished patients with breath-holding spells and syncope from patients with epilepsy. Even a small increase of 0.5 seconds in the RR interval demonstrated a sensitivity of 46%, with a specificity of 98%. Ocular compression performed during an EEG is useful in distinguishing patients with breath-holding spells and syncope from those with epileptic seizures. A requirement of a 2-second period of asystole with ocular compression excludes many patients. Our data indicate that an RR interval increase of 0.5 seconds over baseline identifies additional patients with increased vagal tone. Prompt and accurate diagnosis of the etiology of loss of consciousness might preclude the need for further extensive and expensive evaluation and reduce patient and parental distress.     

PLED pattern and its clinical significance in stroke patients

The pathophysiological connection between periodic lateralized epileptiform discharges (PLED) and epileptic seizures is still not clear. In the study clinical data and EEG findings were analysed in 22 patients aged 43-90 years with a history of stroke in whom EEG disclosed PLED. Eleven patients were studied in the acute phase of stroke and 11 were studied years after stroke when the diagnosis was established of poststroke epilepsy. In 2 patients in acute stroke group single epileptic seizures occurred and 5 had partial status epilepticus. In the group with poststroke epilepsy 4 had single seizures and 4 had epileptic status with partial epilepsy seizures. Thus, in 15 out of 22 patients PLEDs were noted after epileptic seizures. In all cases PLED appearance was connected with consciousness disturbances, lasting 1 to 17 days. In 6 cases PLED pattern was interrupted by seizure activity over one hemisphere, in 3 of them partial epileptic seizures were associated with it. In acute phase of stroke neuroimaging demonstrated the presence of fresh ischaemic foci, but in cases of poststroke epilepsy no such fresh foci were observed. These results suggest that PLED frequently can be associated with epilepsy, and in some patients it can be a bioelectrical manifestation of partial status epileptic.     

The EEG in nonepileptic seizures.

Nonepileptic seizures are episodes that resemble seizures but are not epileptic. The importance of EEG in the diagnosis of NES is that misread (overread) EEGs are an important contributor to the misdiagnosis of epilepsy. About 20% to 30% of patients with refractory "seizures" seen at epilepsy centers have been misdiagnosed, and the vast majority have psychogenic nonepileptic seizures (PNES). Many such patients have had previous EEGs interpreted as epileptiform. These misdiagnoses based on EEG are easily perpetuated, complicate management, and adversely affect outcome. The reasons for the overinterpretation of EEGs include the common misconception that phase reversals indicate abnormalities and not applying strict criteria to make sharp transients epileptiform. The diagnosis of PNES typically begins with a clinical suspicion and then is confirmed with EEG-video monitoring. However, ictal EEG may be negative in some partial seizures and may be uninterpretable because of artifacts. Movements can generate rhythmic artifacts that mimic an electrographic seizure. Analysis of the ictal semiology (i.e., video) is at least as important as the ictal EEG. Provocative techniques, activation procedures, or "inductions" can also be useful for the diagnosis of PNES.     

Differenzialdiagnostische Kl?rung durch implantierten ?Loop“-Rekorder

It is not yet sufficiently clarified which patients who suffer from repetitive sudden losses of consciousness (SLOC) and for whom the differential diagnosis between epileptic seizure and syncope is open would benefit from the use of an implantable loop recorder (ILR). This article describes the case of a patient who suffered from infrequent SLOC and who had been referred in order to improve the treatment of the suspected drug-resistant epilepsy. The patient had shown normal results during extensive cardiological work-up and presented with normal neurological, magnetic resonance imaging (MRI) and routine electrocardiogram (EEG) findings. Long-term video EEG also did not reveal any abnormalities. Typical examples of syncope, epileptic and psychogenic non-epileptic seizures had been shown to the husband as an eyewitness but he was still not able to help with the diagnosis. An ILR was implanted and the typical attacks could be recorded and were diagnosed as asystole. The patient was treated with a pacemaker and has remained free from attacks with a follow-up of 4 years. It can be concluded that in adult patients with infrequent SLOC in spite of normal neurological, neuroimaging and long-term EEG results and in spite of normal cardiological findings cardiac syncope is more probable than epileptic seizures. Implantation of an ILR offers a chance to find the correct diagnosis and is therefore recommended if such clinical circumstances exist.     

以癫痫 精神异常为首发表现的糖尿病17例临床误诊分析

目的：探索以癫痫和精神异常为首发的糖尿病临床特点、误诊原因及诊断体会。方法我院2002-02-2012-02收治的各种类型癫痫76例临床资料，其中17例以癫痫样发作和精神异常为首发，完善相关医技检查后，确诊为糖尿病性癫痫、糖尿病性精神病。结果首诊误诊率为22.4％，分别被误诊为癫痫15例，精神病2例。结论临床医生应提高对以癫痫样、精神病样发作为首发的糖尿病认识，当遇到类似症状患者除想到癫痫精神病外，还应想到糖尿病的可能，及时选做尿糖、血糖监测，并给予胰岛素等降糖药治疗，可明确诊断。     

Clinical features, EEG findings and diagnostic pitfalls in juvenile myoclonic epilepsy: a series of 63 patients

Juvenile myoclonic epilepsy (JME) is a common idiopathic generalized epileptic syndrome distinctively characterized by myoclonic jerks often associated to generalized tonic-clonic seizures (GTCS) and typical absence seizures. In spite of typical clinical and EEG profiles, JME is widely underdiagnosed. In the present study we retrospectively revised clinical and EEG data of JME patients referring to our Epilepsy Service. A diagnosis of JME could be made in 63 patients, that is 5.7% of all the epileptic patients referring to our Service and 25.9% of those suffering from an idiopathic generalized epilepsy. General features as well as modality of onset and course of the syndrome of our JME subjects were in accordance with literature. Regarding EEG findings, asymmetries were detected in 38.1% of cases. At referral to our Service only 31.7% of JME patients were correctly diagnosed. Main factors responsible for misdiagnosis were failure in eliciting a history of myoclonic jerks and misinterpretation of myoclonic jerks as simple partial seizures. EEG asymmetries were misleading in 13 patients. In conclusion, a correct JME diagnosis is strictly dependent on the knowledge of the syndrome leading the interviewer to look for and correctly interpret myoclonic jerks whereas EEG is just an ancillary diagnostic tool.     

Usefulness of the Head-Upright Tilt Test for Distinguishing Syncope and Epilepsy in Children

PURPOSE: Episodic loss of consciousness in children, whether or not associated with hypertonia or short-duration clonic movements, presents a diagnostic challenge to the pediatrician and child neurologist. We provide some evidence of the usefulness of the head-upright tilt test for investigating the causes of transient loss of consciousness in children, and for distinguishing between syncope, convulsive syncope, and epilepsy. METHODS: We studied nine children previously diagnosed as epileptic on the basis of compatible clinical events and epileptiform findings in routine EEGs who were treated over the long term with antiepileptic drugs, but whose clinical records suggested syncope or convulsive syncope rather than epilepsy on reevaluation. All subjects underwent head-upright tilt testing. RESULTS: The tilt-test result was positive in all nine cases, with the patients reporting the same symptoms as in the previously considered epileptic attacks. CONCLUSIONS: Inadequate histories and misuse/overinterpretation of EEG results often lead to misdiagnosis of epilepsy in children. The head-upright tilt test is a useful and reliable diagnostic technique, allowing syncopal events to be induced and evaluated under controlled conditions. In a subset of patients, it may help to distinguish epilepsy from simple or convulsive syncope.     

Ictal yawning in a patient with drug-resistant focal epilepsy: video/EEG documentation and review of literature reports

Yawning is an involuntary sequence of mouth opening, deep inspiration, brief apnea, and slow expiration. Few cases of yawning as a clinical sign of epileptic seizures, ictally or postictally, have been reported. We report the video/EEG documentation of yawning as an ictal sign in a 31-year-old patient affected by drug-resistant focal epilepsy symptomatic of bilateral perisylvian polymicrogyria. Since the age of 10 she has had seizures characterized by yawning, staring, and eye blinking. Bilateral rhythmic frontotemporal spikes and waves characterized her EEG. We reviewed all reported cases and compared clinical and EEG features. We believe that yawning as part of an epileptic seizure might be considered a rare automatic behavior, like other automatisms frequently reported in epileptic seizures. Automatisms are more frequently described in patients with temporal lobe epilepsy, and involvement of the temporal lobe in most of the published cases may have led to this explanation. It is possible that yawning within epileptic seizures could be considered activation of distinct symptomatogenic cortex rather than a release phenomenon. This rare ictal manifestation should be recognized as epileptic to avoid misdiagnosis and treatment failure.     

额叶癫痫发作录像脑电图特点分析

目的通过录像脑电图观察额叶癫痫的临床特征、发作期及发作间歇期的脑电图特点。方法使用录像脑电图（ｖｉｄｅｏＥＥＧ,ＶＥＥＧ）对５０例确诊为额叶癫痫的患者进行常规及长时间记录,对其中１７例（２０次）癫痫发作的临床表现及脑电图所见进行分析。结果额叶癫痫常见的发作形式有：姿势性发作,具有额叶癫痫特点的自动症;复杂部分性发作时伴发声、偏转或表情的变化,有时出现发作性情绪改变或强迫思维等少见症状。其发作特点为：持续时间短,发作相对较频繁,无明显发作后意识障碍。发作间歇期脑电图有时可无阳性所见,典型的临床发作及发作时ＶＥＥＧ记录到的额部爆发性节律有助于诊断。本组９例儿童期起病的额叶癫痫患者,以夜间频繁的躯体自动症发作为主,检查均未发现相应的脑器质性病变。脑电图睡眠描记可见频繁的额部导联癫痫样放电。临床治疗观察预后良好,提示可能为一组儿童原发性部分发作型癫痫综合征。结论额叶癫痫是一组较为特征性的癫痫综合征,临床并不少见,及时而正确的诊断有助于治疗。     

Adult‐onset photosensitivity: clinical significance and epilepsy syndromes including idiopathic (possibly genetic) photosensitive occipital epilepsy

To evaluate the clinical associations of adult‐onset photosensitivity, we studied the clinical and EEG data of patients who were referred due to a possible first seizure and who had a photoparoxysmal response on their EEG. Patients with clinical evidence of photosensitivity before the age of 20 were excluded. Of a total of 30 patients, four had acute symptomatic seizures, two had vasovagal syncope, and 24 were diagnosed with epilepsy. Nine of the 24 patients had idiopathic (genetic) generalized epilepsies and predominantly generalized photoparoxysmal response, but also rare photically‐induced seizures, while 15 had exclusively, or almost exclusively, reflex photically‐induced occipital seizures with frequent secondary generalization and posterior photoparoxysmal response. Other important differences included a significantly older age at seizure onset and paucity of spontaneous interictal epileptic discharges in patients with photically‐induced occipital seizures; only a quarter of these had occasional occipital spikes, in contrast to the idiopathic (genetic) generalized epilepsy patients with typically generalized epileptic discharges. On the other hand, both groups shared a positive family history of epilepsy, common seizure threshold modulators (such as tiredness and sleep deprivation), normal neurological examination and MRI, a generally benign course, and good response to valproic acid. We demonstrated that photosensitivity can first occur in adult life and manifest, either as idiopathic (possibly genetic) photosensitive occipital epilepsy with secondary generalization or as an EEG, and less often, a clinical/EEG feature of idiopathic (genetic) generalized epilepsies. Identification of idiopathic photosensitive occipital epilepsy fills a diagnostic gap in adult first‐seizure epileptology and is clinically important because of its good response to antiepileptic drug treatment and fair prognosis.     

Clinical and EEG Asymmetries in Juvenile Myoclonic Epilepsy

Summary: We reviewed records of 85 patients with juvenile myoclonic epilepsy (JME) for significant asymmetries in clinical seizures or the EEG. We noted asymmetries in 26 of 85 patients (30.6%). Only 2 patients had both clinical and EEG asymmetries; 12 had clinical asymmetries and 12 had EEG asymmetries exclusively. Analysis of patients with and without asymmetries showed no statistically significant differences in comparisons of sex, age at seizure onset, family history of epilepsy, seizure type, or response to treatment. The delay in diagnosis was greater in JME patients with asymmetries (9.5 years) than in JME patients with no asymmetries (7.5 years), but this difference was not statistically significant. Fourteen of the 26 patients with asymmetries (53.8%) were initially misdiagnosed as having partial seizures. Asymmetries in JME patients are not only common, but are also a frequent cause of misdiagnosis.     

Symptoms of narcolepsy in children misinterpreted as epilepsy.

Differentiating an epileptic seizure from some other paroxysmal event is a common challenge in clinical practice. Many paroxysmal events mimic epileptic seizures and misdiagnosis can have disastrous consequences. Incorrectly identifying an event as an epileptic seizure can lead to unnecessary investigations and instigation of inappropriate treatment regimes. We report five patients referred to regional Paediatric Neuroscience Centres for investigation of events initially suspected of being epileptic seizures. All five patients were subsequently diagnosed as having narcolepsy. Suspected diagnoses were absence epilepsy (four patients), generalized epilepsy with astatic seizures (two patients) and focal epileptic seizures (two patients). Diagnostic confusion arose because lack of responsiveness due to excessive sleepiness was mistaken for epileptic absences, and cataplexy was confused with a variety of seizure types. In each case, videotape recording of clinical events aided in making the diagnosis of cataplexy. At presentation, all five children had excessive daytime sleepiness with cataplexy. Following correct diagnosis and appropriate management, an improvement in symptoms was reported in all cases. Narcolepsy/cataplexy should be included in the differential diagnoses of paroxysmal disorders, particularly if there are associated sleep symptoms or behavioural difficulties. It is important to take a sleep history when evaluating any disorder of the central nervous system.     

Neurocardiogenic syncope: frequency and consequences of its misdiagnosis as epilepsy

BACKGROUND: Neurocardiogenic syncope (NCS) can be mistaken as a seizure. We reviewed the frequency and diagnostic consequences of this misdiagnosis. METHODS: A retrospective review of outpatient adult epilepsy clinic charts (QEII Health Sciences Centre, Halifax, NS) was conducted to identify NCS patients referred with a provisional diagnosis of seizures. Charts were reviewed in detail with an emphasis on the consequences of misdiagnosis. RESULTS: Of 1506 consecutive referrals to the epilepsy clinic, 194 (12.9%) ultimately had a clinical diagnosis of NCS. Mean age was 38 +/- 16 years (mean age of syncopal onset was 28 +/- 16 years). Two-thirds of referrals were from primary care physicians (including emergency departments) and 18% from neurologists. Thirty-five percent were prescribed antiepileptic drugs (AEDs) prior to referral with eight patients (4.1%) experiencing hypersensitivity reactions. Three of five women had adverse pregnancy outcomes while taking AEDs. One-third of patients had restrictions placed on their driving privileges while 11 patients (5.7%) had their employment interrupted. Diagnostic modalities used in the work-up included EEG (90%), CT head (51%), and MRI head (15%). CONCLUSIONS: NCS is commonly misdiagnosed as epilepsy. Some patients had an incorrect diagnosis for > 10 years. Patients with this misdiagnosis are often excessively investigated, inappropriately treated, and have unnecessary restrictions placed on driving and employment.     

Contribution of ambulatory EEG recording (Medilog 9000) in a population of epileptics

Thirty-four epileptic patients, aged 9 to 36, were submitted to A/EEG between May 1987 and July 1988. All patients had a thorough clinical and EEG work-up including long-term conventional EEG, afternoon polygraphic sleep recording and, in some cases, full-night EEG and video monitoring. Patients were divided into 2 groups: group I included 19 patients (18 with symptomatic partial epilepsy (SPE) and 1 with idiopathic generalized epilepsy (IGE) in whom no seizure had ever been recorded in spite of EEG recordings averaging a total of 16 hrs 10 min, awake and asleep); group II included 15 subjects (6 with SPE, 5 with IGE, 3 with symptomatic GE and 1 with undetermined epilepsy) in whom one or several seizures had been recorded. A/EEG was performed in order to: 1) obtain better clinical and EEG characterization of seizures, 2) study the circadian distribution of seizures, 3) verify the efficacy of drug treatment and, 4) establish the epileptic or non-epileptic nature of some ictal events. The results of A/EEG were considered positive in 52.63% of group I patients and in 93.33% of group II patients. The authors discuss the specific advantages of A/EEG vs conventional EEG: recording of seizures with random occurrence, of seizures accompanied by falls, checking the remission of seizures.     

Merosin-negative congenital muscular dystrophy,occipital epilepsy with periodic spasms and focal cortical dysplasia. Report of three Italian cases in two families

We report clinical, EEG and neuroimaging findings of three patients in two Italian families with merosin-negative congenital muscular dystrophy (CMD), drug-resistant occipital epilepsy, diffuse persistent cerebral white matter changes and focal cortical dysplasia. Clinical and epilepsy histories, EEG and neuroimaging findings were very similar in all patients. Seizures started in childhood and mainly consisted of periodic spasms, a particular type of partial seizure characterized by clusters of epileptic spasms. The motor expression of the spasms was very mild so that they had been frequently missed or misinterpreted as non-convulsive generalized absence seizures. Interictal EEG showed occipital spike-waves and bilateral synchronous slow spike-wave discharges. Ictal EEG showed prolonged periodic sequences of slow waves with associated fast rhythm complexes, characteristic of periodic spasms. Two patients had normal intelligence, one patient presented moderate mental retardation. Focal cortical dysplasia in the posterior areas of the brain, in addition to marked diffuse white matter alterations, was detected in the magnetic resonance images of all patients. Findings in these patients indicate that in merosin-negative CMD brain involvement can include cortical dysplasia, in addition to white matter changes. In such cases the brain damage can lead to a childhood-onset localization-related symptomatic occipital epilepsy. Epileptic seizures and cortical dysplasia can be, however, difficult to detect in CMD. The clinical semiology of epileptic seizures may in fact be modified because of muscular weakness. This implies that epilepsy may be misdiagnosed or even missed and EEG-polymyographic recordings may be necessary to identify it. Similarly, cortical dysplasia may be very localized and visible by neuroimaging only if it is carefully investigated on the basis of epileptological and EEG-polymyographic findings.     

Understanding Lennox–Gastaut syndrome: insights from focal epilepsy patients with Lennox–Gastaut features

To delineate the clinical and EEG features of adults with focal epilepsy associated with a generalized paroxysmal fast activity (GPFA) pattern on EEG who developed refractory seizures, notably drop attacks, but do not fulfill the classical triad for the diagnosis of Lennox–Gastaut syndrome (LGS) and provide further insight into LGS mechanisms. Among 957 patients admitted to video-EEG monitoring between 2002 and 2015, we retrospectively research adult patients with refractory focal epilepsy, drop attacks and GPFA on EEG. We collected demographic, anamnestic, and clinical data from medical records. We reviewed for all patients the interictal and ictal video-EEG recordings. We identified ten patients with focal epilepsy and electro-clinical features of LGS. As compared to classical LGS patients, our patients: (1) began epilepsy later (15.4 ± 8 years); (2) exhibited exclusively focal onset seizures, including drop attacks seizures linked to focal asymmetrical tonic posturing seizures; (3) had a stable cognition over time and (4) evolved favourably with a good secondary response to treatments in 80% of cases. Interestingly, all patients exhibited apparent diffuse interictal and ictal EEG abnormalities but a detailed analysis revealed that 50% had asymmetrical GPFA and 70% secondary bilateral synchrony processes. We may hypothesize here that a process of “secondary LGS” occurred which produced a worsening of seizures with the apparition of drop attacks and GPFA on EEG. This study brings arguments to consider that some cases of LGS could be linked to the development of a “secondary epileptic network” driven by a primary focal epileptic zone.     

Cardiogenic syncope diagnosed as epileptic seizures: the importance of ECG during video‐EEG recording

We describe four patients with a previous diagnosis of epilepsy. After reviewing the ECG during the video‐EEG recording, cardiogenic syncope, resulting from a cardiac arrhythmia, was identified as the cause of the seizures. Epileptic disorders and cardiogenic syncope may both manifest with convulsions, loss of consciousness, and loss of postural tone, leading to a high level of misdiagnosis. The one‐lead ECG during video‐EEG monitoring is a key component, which may allow correct diagnosis and treatment.     

Video-EEG in syncopal attack due to ocular compression in an adolescent mistreated for epilepsy.

Vasovagal syncope can be confused with epileptic seizure. In this situation, eye compression may be performed during EEG. We present a video-EEG of a patient in whom eye compression produced a typical syncope. Before this recording, the patient had been treated for five years with sodium valproate because of a misdiagnosis of epilepsy. The diagnosis of neurally-mediated syncope was not difficult on the basis of the clinical history, but the reproduction of syncope reinforced the correct diagnosis. Ocular compression is now only indicated in exceptional circumstances and should be performed with precautions. The video of this episode in an adolescent should be of considerable educational value to those who are confronted to diagnostic work-up of transient loss of consciousness.     

Electroencephalograms (EEG) in 250 patients with epilepsy in a cysticercosis endemic area in Burundi]

OBJECTIVES: This work aimed at describing EEG abnormalities in epileptic patients living in areas endemic for cysticercosis, underlining the electroclinical correlations and discussing the interest of EEG examination in this context. METHODS: During a case-control study, 250 EEGs from patients with epilepsy were recorded with a portable system. Types of seizures were assessed clinically and from information obtained through a standardised questionnaire, and along with EEG were related to the results of cysticercosis serological tests. RESULTS: Among the 249 EEGs, 48% were normal, 5.2% had epileptic abnormalities, 6.8% showed an association between epileptic abnormalities and slow alterations. Slow theta and delta abnormalities were found in 21.8% of cases, and isolated deterioration of basic rhythms was observed in 17.3% of cases. Most seizures were generalized, and 61% of the patients had positive serology. One EEG was uninterpretable and another showed isolated spikes. Electroclinical agreement was considered to be satisfactory in 33 patients, and was better with the epileptic than with slow abnormalities. The existence of epileptiform EEG abnormalities confirmed clinically diagnosed epilepsy, but did not allow etiological diagnosis. Electroserological agreement was good in 24 patients. A significant association (Chi2, p = 0.03) existed between slow focal abnormalities and positive cysticercosis serology. Conversely, no significant association was detected between epileptic patterns and serology results. CONCLUSION: While the EEG alone clearly does not allow aetiological diagnosis, its joint use with clinical and biological results was a key element of the etiological and therapeutic discussion. When it shows focal abnormalities in a patient with epilepsy living in a high prevalence cysticercosis area, it confirms the clinical suspicion of neurocysticercosis. Morphological imagery alone can provide etiological information on the seizures by showing the nature and localization of the parenchymal lesions.     

Long-term EEG monitoring in epilepsy diagnosis

EEG long-term monitorings were carried out in 149 patients using a portable 4-channel miniature recorder system. In most cases EEG was recorded for 48 hours. In addition to preceding routine EEG controls, long-term EEG monitoring disclosed epileptic phenomena in 32.7% of patients suspected for epileptic seizures from their history. This gain of information was based mainly on the detection of abnormal potentials or epileptic seizures appearing during sleep. Using EEG long-term recording numerous EEG routine controls could be replaced which otherwise are often necessary for ensuring the diagnosis of epilepsy. If the patient's history, however, gives only poor reason to believe epileptic seizures, positive findings in EEG long-term monitorings are unlikely. Consequently, careful evaluation of the patient's history is crucial for the indication of this laborious examination. As the limited number of recorder channels may cause false negative results, normal findings should be utilized with caution. Only the sum of all clinical and neurophysiological data should be used for exclusion of suspected epilepsy. The second, even more important application of EEG long-term recordings is the special examination of patients with known epilepsy, such as studies of the circadian profiles of epileptic excitability, documentation of seizure frequency, and electrographic analysis of the course of seizure. Therapy control of epileptic patients can be improved by such informations. In view of the large amount of data which results from long-term recordings, computer assisted methods supporting the visual analysis are necessary. In this regard the continuous spectral analysis of the EEG long-term recordings proved to be highly useful.