Video-polygraphic Recordings Research Articles

Epileptic belly dancing: a video-polygraphic recording.

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Circadian and state-dependent core body temperature in people with spinal cord injury

Prospective cohort study. To analyze the circadian rhythm and state-dependent modulation of core body temperature (Tcore) in individuals with spinal cord injury (SCI) under controlled environmental conditions. Institute of the Neurological Sciences of Bologna, Italy. We assessed 48-h rectal Tcore and sleep-wake cycle by means of video-polygraphic recording in five cervical SCI (cSCI), seven thoracic SCI (tSCI), and seven healthy controls under controlled environmental conditions. cSCI showed higher night-time Tcore values with reduced nocturnal decrease, higher MESOR and earlier acrophase compared with tSCI and controls (p < 0.05 in all comparisons). The mean Tcore values during wake and non-rapid eye movement (NREM) and rapid eye movement (REM) sleep stages were higher in cSCI compared with tSCI and controls (p < 0.05). Tcore variability throughout the 24 h differed significantly between cSCI, tSCI, and controls. cSCI had higher Tcore values without physiological night-time fall compared with controls and tSCI, and a disrupted Tcore circadian rhythm. Furthermore, SCI individuals did not display the physiological state-dependent Tcore modulation. The disconnection of the sympathetic nervous system from its central control caused by the SCI could affect thermoregulation including Tcore modulation during sleep. It is also possible that the reduced representation of deep sleep in people with SCI impairs such ability. Further studies are necessary to evaluate whether improvement of sleep could ameliorate thermoregulation and vice versa.

Comorbilidades y gravedad de la apnea del sueño. Estudio en una cohorte de pacientes portugueses

Obstructive sleep apnoea syndrome (OSAS) is frequently associated to other morbid conditions that act as risk factors influencing OSAS morbidity and mortality. To analyse the presence of co-morbidities in OSAS patients, recruited from a sleep outpatient clinic in Northern Portugal, stratified as a function of OSAS severity. A cohort of 319 sleep-disordered patients was assessed by clinical and sleep video-polygraphic recording. Patients (n = 209) with sleep respiratory distress had OSAS (n = 145) and severity defined according to Apnoea/Hypopnea Index (AHI); 64 had primary snoring or respiratory distress with AHI < 5; and 110 had other sleep disorders. A full individual background study was possible in 128 OSAS patients. The association to unique or multiple co-morbidities was assessed by clinical and analytical studies in general group or as a function of OSAS severity. The presence of co-morbidities was of 75% in all OSAS patients and of 79.5% in the severe group of OSAS. Forty seven of patients had only one co-morbidity. The most common was obesity (56.3%) followed by high blood pressure, diabetes and other cardiovascular disorders. Obesity was present in 84% among the most severe OSAS cases and always present in those with multiple co-morbidities. When compared with the group of patients without sleep respiratory distress the co-morbidity condition was more frequently related to OSAS (p = 0.0196). Comorbidities are commonly associated to OSAS independently of disease severity. Among the comorbidities present obesity was the most common in the most severe OSAS cases.

Spinal muscular atrophy associated with progressive myoclonic epilepsy: A rare condition caused by mutations in ASAH1

To present the clinical features and the results of laboratory investigations in three patients with spinal muscular atrophy associated with progressive myoclonic epilepsy (SMA-PME), a rare condition caused by mutations in the N-acylsphingosine amidohydrosilase 1 (ASAH1) gene. The patients were submitted to clinical evaluation, neurophysiologic investigations (that included wakefulness and sleep electroencephalography [EEG], video-polygraphic recording with jerk-locked back-averaging, multimodal evoked potentials, and electromyography), brain magnetic resonance imaging (MRI), biochemical screening, muscle and skin biopsies, and molecular genetic analysis. The main clinical features were onset in childhood with proximal muscular weakness, generalized epilepsy with absences and myoclonic seizures, cognitive impairment of variable degree; the course was progressive with muscle wasting and uncontrolled epileptic seizures. In one patient, earlier onset before the age of 2years was associated with a more complex clinical picture, with abnormal eye movements, progressive cognitive impairment, and a more rapid and severe course. EEG/polygraphic data were consistent with PME, demonstrating generalized spike-and-wave discharges, evidence of positive and negative myoclonia, and prominent photosensitivity. In one patient, transcranial magnetic stimulation showed a hyperexcitable motor cortex, whereas somatosensory evoked potentials were unaffected. Possible involvement of the central acoustic and visual pathways was suggested by abnormal auditory and visual evoked potentials. Muscle biopsies showed typical signs of neurogenic damage. Molecular genetic analysis showed mutations of the ASAH1 gene. Our data indicate that SMA-PME associated with ASAH1 mutations is a genetically distinct condition with specific clinical and neurophysiologic features. Further studies are warranted to explore the role of the ASAH1 gene in muscle and brain function.

Study of epileptic drop attacks in symptomatic epilepsy of early childhood - differences from those in myoclonic-astatic epilepsy.

We studied epileptic drop attacks (EDA) in symptomatic epilepsy of early childhood by means of video-polygraphic recordings and compared clinico-electrical differences in EDA among patients with idiopathic myoclonic-astatic epilepsy (MAE). Subjects consisted of 21 children with symptomatic epilepsy and 20 with idiopathic MAE whose EDA were documented at an age between 7 months and 6 years. The seizure types causing EDA as well as other demographic data were compared between the two epilepsy types. A video-polygraphic study captured a total of 188 EDA (median: 8) in patients with symptomatic epilepsy and 182 EDA (median: 7) in those with idiopathic MAE. In the former, EDA were caused by epileptic spasms (ES) corresponding to generalized biphasic slow discharges, sharp-and-slow wave complexes, or the flattening of ongoing background activity in 15 patients, atonic seizures associated with runs of generalized spike-and-wave complexes in four patients, and myoclonic-atonic seizures in the remaining two patients. The mode of occurrence of EDA in ES was periodic clustering in eight of 15 patients. Interictal EEG revealed generalized irregular multiple spikes-and-waves with focal or multifocal accentuations. Sixteen idiopathic MAE patients had myoclonic-atonic seizures while the remaining four had myoclonic-flexor seizures, all corresponding to generalized high amplitude spikes or polyspike-and-wave complexes and occurring singly. EDA often seen in young children with symptomatic epilepsy were most frequently caused by flexor type ES and rarely by myoclonic-atonic seizures, a hallmark seizure type of MAE. In a clinical setting, the occurrence of periodic clusters and independent focal or multifocal accentuations of generalized spike-and-wave complexes in interictal EEG may indicate EDA caused by ES.

Corpus callosotomy in a patient with startle epilepsy

Startle epilepsy is a syndrome of reflex epilepsy in which the seizures are precipitated by a sudden and surprising, usually auditory, stimulus. We describe herein a girl who had been suffering with startle-induced seizures since 2 years of age. She had focal, tonic and tonic-clonic seizures, refractory to antiepileptic treatment. Daily tonic seizures led to very frequent falls and morbidity. Neurologically, she had no deficit. Interictal EEG showed slow waves and epileptiform discharges in central and fronto-central regions. Video-polygraphic recordings of seizures, triggered by stimuli, showed generalised symmetric tonic posturing with ictal EEG, characterised by an abrupt and diffuse electrodecremental pattern of fast activity, followed by alpha-theta rhythm superimposed by epileptic discharges predominantly over the vertex and anterior regions. Magnetic resonance imaging showed no abnormalities. Corpus callosotomy was performed when the patient was 17. Since surgery, the patient (one year follow-up) has remained seizure-free. Corpus callosotomy may be considered in patients with startle epilepsy and tonic seizures, in the absence of focal lesions amenable to surgery. [Published with video sequences].

Ictal video-polygraphic features of perioral myoclonia with absences

There have been few case reports of perioral myoclonia with absences (POMA) because of the lack of video-polygraphic recordings clarifying the electroencephalogram (EEG)–electromyogram (EMG) correlations. We describe one of the first video-polygraphic studies of POMA in a patient who underwent repeated and prolonged split-screen video-polygraphic recordings. The ictal EEG showed generalized and irregular discharges of spikes or multiple spikes and slow waves, while two concomitant EMG patterns appeared: (1) a rhythmic enhancement of the orbicularis oris and masseter muscles on both sides with minimal asymmetry corresponding to perioral movements, and (2) a progressive increment in muscular tone in the mylohyoideus muscle corresponding to oroalimentary automatisms. Myoclonic jerks were inconstantly time-locked to the spike component of the spike–wave complex. The evidence of a complex pattern of activation of the facial muscles suggests that the involvement of subcortical central pattern generators, related to masticatory activity, through the disinhibitory effect of the spike–wave discharge is a possible pathophysiological mechanism underlying POMA.

Decreased Nocturnal Movements in Patients with Facioscapulohumeral Muscular Dystrophy

Reduced mobility during sleep characterizes a variety of movement disorders and neuromuscular diseases. Facioscapulohumeral muscular dystrophy (FSHD) is the third most common form of muscular dystrophy in the general population, and people with FSHD have poor sleep quality. The aims of the present study were to evaluate nocturnal motor activity in patients with FSHD by means of videopolysomnography and to verify whether activity was associated with modifications in sleep structure. We enrolled 32 adult patients affected by genetically confirmed FSHD (18 women and 14 men, mean age 45.1 +/- 13.4 years) and 32 matched control subjects, (18 women and 14 men, mean age 45.5 +/- 11.4 years). Major body movements (MBM) were scored in videopolygraphic recordings in accordance with established criteria. An MBM index was calculated (number of MBM per hour of sleep). The FSHD group showed a decrease in the MBM index (FSHD: 1.2 +/- 1.1; control subjects: 2.3 +/- 1.2, analysis of variance F = 13.672; p = 0.008). The sleep pattern of patients with FSHD, as compared with that of controls, was characterized by longer sleep latencies, shorter sleep durations, an increased percentage of wake during sleep, and a decreased percentage of rapid eye movement sleep. In the patient group, the MBM index was inversely correlated with severity of disease (Spearman test: r30 = -0.387; p < 0.05). The present findings suggest that patients with FSHD have a reduced number of nocturnal movements, which is related to disease severity. Reduced movement in bed may contribute to the sleep modifications observed in these patients.

Neuroethological approach to frontolimbic epileptic seizures and parasomnias: The same central pattern generators for the same behaviours

The aim of this report is not to make a differential diagnosis between epileptic nocturnal seizures and non-epileptic sleep-related movement disorders, or parasomnias. On the contrary, our goal is to emphasize the commonly shared semiological features of some epileptic seizures and parasomnias. Such similar features might be explained by the activation of the same neuronal networks (so-called ‘central pattern generators’ or CPG). These produce the stereotypical rhythmic motor sequences – in other words, behaviours – that are adaptive and species-specific (such as eating/alimentary, attractive/aversive, locomotor and nesting habits). CPG are located at the subcortical level (mainly in the brain stem and spinal cord) and, in humans, are under the control of the phylogenetically more recent neomammalian neocortical structures, according to a simplified Jacksonian model. Based on video-polygraphic recordings of sleep-related epileptic seizures and non-epileptic events (parasomnias), we have documented how a transient “neomammalian brain” dysfunction – whether epileptic or not – can ‘release’ (disinhibition?) the CPG responsible for involuntary motor behaviours. Thus, in both epileptic seizures and parasomnias, we can observe: (a) oroalimentary automatisms, bruxism and biting; (b) ambulatory behaviours, ranging from the classical bimanual–bipedal activity of ‘frontal’ hypermotor seizures, epileptic and non-epileptic wanderings, and somnambulism to periodic leg movements (PLM), alternating leg muscle activation (ALMA) and restless legs syndrome (RLS); and (c) various sleep-related events such as ictal fear, sleep terrors, nightmares and violent behaviour.

Myoclonic status misdiagnosed as movement disorders in Rett syndrome: A video-polygraphic study

Myoclonic jerks and myoclonic status (MS) are sometimes difficult to distinguish clinically from movement disorders such as hand stereotypies, tremor, and dystonia in Rett syndrome. We describe a rare and complete video-polygraphic study of a girl with Rett syndrome (MECP2 mutation) and MS misdiagnosed as movement disorders and disclosed after video-polygraphic recordings. Corresponding to closely recurring activity of diffuse spike and polyspikes–wave-type paroxysms, rhythmic and, especially, arrhythmic myoclonias, usually asymmetrical and asynchronous, involving mainly right muscle deltoid and rarely followed by an inhibitory phenomenon, appeared. The MS improved and, most importantly, disappeared after the use of levetiracetam, with an evident antimyoclonic efficacy and a marked improvement of daily life for the patient and her caregivers. The difficulty in differentiating some typical nonepileptic behavioral features and movement disorders of patients with Rett syndrome from seizures was overcome using prolonged video-polygraphic recordings in our case.

Videopolygraphic and functional MRI study of musicogenic epilepsy. A case report and literature review

A 36-year-old right-handed man, who had experienced partial seizures since the age of 24 every time he played or listened to music with a strong emotional charge, underwent videopolygraphic recording, including autonomic variables, and brain fMRI study during which he listened to both "neutral" and "emotionally charged" music. Three right temporal seizures recorded during videopolygraphic monitoring were elicited by listening to the triggering song. The fMRI study disclosed activation in right acoustic areas during "neutral music," whereas an "emotionally charged melody" provoked widespread activation over the right fronto-temporo-occipital area before seizure onset. The literature review disclosed 110 published cases of musicogenic epilepsy that seemed to suggest a right-sided predominance of the epileptogenic zone. Our results support the role of the right temporal lobe in musicogenic epilepsy and demonstrate that the cerebral areas activated during the period of strong emotion leading to the seizures encompass the auditory cortex activated by neutral music.

Startle epilepsy complicating aspartylglucosaminuria

A 21-year-old right-handed man with definite diagnosis of aspartylglucosaminuria (AGU) presented with a 5-year history of progressive severe gait disturbance with frequent falls and generalized epileptic seizures triggered by unexpected stimuli. At one time, he was confined to a wheelchair because of the frequent falls. Electromyogram recording showed a large, excessive and not habituating motor startle response, with the classical and stereotyped order of muscle recruitment. During video-polygraphic recording, we recorded a reflex generalized tonic seizure triggered by a loud, unexpected acoustic stimulus. Brain magnetic resonance (MR) revealed no structural abnormality. A diagnosis of abnormal startle and startle epilepsy (SE) was made. The addition of clonazepam to valproate and phenobarbital led to a dramatic improvement in his abnormal startle and SE, and the patient was able to walk alone unaided. This report illustrates, for the first time, that abnormal startle and SE may occur in AGU and complicate its clinical picture. Recognition of this entity in AGU is important, as progressive gait disorder with frequent falls could be easily misinterpreted as an additional irreversible manifestation of the ongoing neurological deterioration characteristic of AGU.

Ictal pattern of EEG and muscular activation in symptomatic infantile spasms: a videopolygraphic and computer analysis.

To investigate ictal muscular phenomena characterizing symptomatic infantile spasms (ISs) and their relation to ictal EEG. Four children with severe encephalopathy, neurologic impairment, and refractory ISs related to different dysplastic lesions, underwent videopolygraphic recordings collecting surface electromyogram (EMG) activity from several cranial and limb muscles to evaluate the pattern of muscular recruitment, duration, and side-to-side asymmetry of ISs. Acquired data were stored for off-line analysis by a computerized polygraphic system. Spasms were characterized by a complex pattern of muscular activation. A constant or rostrocaudal propagation pattern was lacking in all patients. Intervals between the onset of EMG activity in different muscles in each spasm were very long: </=100-200 ms. Two patients, with hemispheric cortical dysplasia and agenesis of the corpus callosum, had asymmetric and asynchronous spasms in which the EMG onset of the muscles contralateral to the affected hemisphere constantly anticipated that of the ipsilateral ones. Backaveraging of EEG activity disclosed a high-amplitude EEG complex on the same side as the dysplastic lesion, preceding or succeeding the contralateral muscle activity onset. In the other two patients with diffuse cortical dysplasia, no EEG transient was related to EMG activity onset. Despite clinical similarity between spasms in the same patient, our data demonstrate the complexity and heterogeneity of these motor phenomena. Our findings cannot be explained simply in terms of cortical or reticular generators like other motor phenomena such as cortical myoclonus or startle reflex.

NREM parasomnias: arousal disorders and differentiation from nocturnal frontal lobe epilepsy

Parasomnias emerging from NREM sleep such as sleep walking, sleep terrors and confusional arousals are considered arousal disorders. Nocturnal video-polysomnography is the gold standard to diagnosing and differentiating parasomnias from other arousals with atypical motor behaviors such as nocturnal frontal lobe epilepsy (NFLE). This form of nocturnal seizures with prominent dystonic-dyskinetic components, in some cases genetic, has been recently identified by means of detailed video-analysis of movements during sleep. The clinical picture of parasomnias (with onset in early childhood, rare episodes of long duration, absence of stereotypy, general disappearance after puberty) is different from that of NFLE (which first occurs between the age of 10 and 20, manifests frequent complex and repetitive behaviors of short duration excluding rare prolonged seizures, nocturnal agitation, some daytime complaints such as fatigue or sleepiness, persistence into adulthood). Patients show no difference from classical sleep parameters whilst microstructure analysis shows sleep instability and arousal fluctuations in parasomnias and NFLE. In children as well, at least in our experience, the differential diagnosis between the two disorders is difficult and requires one or more complete nocturnal video-polygraphic recording. In any case the diagnosis of NFLE should be considered in children with nocturnal motor episodes or nocturnal motor agitation, when the attacks persist; this diagnosis is probably more frequent than expected.

Bilateral centrotemporal spikes triggered by blinking: an unusual form of sensory input with related cortical EEG activity

Objective: To investigate the morphology, scalp topography and temporal relationship with orbicularis oculi muscle contraction of bilateral blink related spikes (BRS) in a 7-year-old boy with chromosomopathy, mild mental retardation and left spontaneous centrotemporal spikes (SS).Methods: The patient underwent video-polygraphic recordings with off-line analysis of SS and BRS by means of spike-averaging and orbicularis oculi contraction-locked averaging techniques respectively. EEG activity related to reflex blinking (evoked by glabellar tapping) was also studied.Results: SS and BRS presented the same morphology, characterised by four peaks (P1, N1, P2, N2). SS were located over the left centroparietal regions, while BRS were placed over both left and right centrotemporoparietal regions and constantly followed the contraction of orbicularis oculi with overlapping peak latencies over C3 and C4 electrodes (P1 72 ms; N1 115 ms; P2 164 ms; N2 236 ms). Reflex blinking evoked a small waveform with the same features as BRS.Conclusions: Our findings suggest that both involuntary and reflex blinking can act as a form of sensory stimulation probably engaging similar nervous pathways and cortical sources in generating EEG abnormalities: the trigeminal system.

Photic reflex myoclonus: a neurophysiological study in progressive myoclonus epilepsies.

To investigate the neurophysiological features of photic reflex myoclonus (PRM) in patients with progressive myoclonus epilepsies (PMEs) of different types (Unverricht-Lundborg disease, Lafora's disease, cryptogenic). All patients underwent computerized video-polygraphic recordings, collecting electromyographic (EMG) activity from several cranial and limb muscles. PRM was elicited by intermittent photic stimulation (IPS). IPS could evoke PRM with a 1:1 relation at frequencies up to 12 Hz. Back-average of the EEG, triggered from the onset of PRM at the upper limbs, showed a contralateral positive-negative transient in central region, preceded by approximately 10 ms by a similar, ipsilateral occipital wave. When IPS induced bilateral jerking, a time lag of approximately 10 ms between the homologous muscles of the two sides was observed, paralleled by a similar delay between the associated contralateral EEG transients in the two central regions, suggesting spread of cortical myoclonic activity from one hemisphere to the other via transcallosal fibers. PRM propagated in different cranial and limb muscles according to a rostrocaudal pattern, with latencies compatible with a transmission along fast-conducting corticospinal motor pathways. In our PME patients, PRM presented uniform neurophysiological features, indicating the participation of both occipital and motor cortices, with bilateral spread presumably mediated by transcallosal connections and propagation down the spinal cord via fast-conducting corticospinal pathways.

Negative myoclonus during valproate-related stupor. Neurophysiological evidence of a cortical non-epileptic origin

We retrospectively reviewed clinical and neurophysiological data of 6 epileptic patients who developed negative myoclonus and stupor a few days after introduction of valproate (VPA). Prompt remission of clinical signs and symptoms followed valproate withdrawal. We attempted to elucidate the pathophysiological mechanism of VPA-induced stupor and provide further polygraphic and backaveraging EEG documentation of negative myoclonus. During VPA-induced stupor electroencephalograms revealed posterior background slowing in all patients. Interictal epileptiform discharges were present in 3 patients. In all 6 patients close examination using simultaneous video-polygraphic recording showed negative myoclonus which was not time-related to lateralized spike discharges. In 2 of 3 patients with no spikes on conventional EEG who underwent backaveraged EEG recordings we detected a large (5 μV) cortical positive-negative wave time-locked (30–40 msec) with the postural modification of the contralateral wrist. This cortical potential was similar to that observed in patients with asterixis secondary to metabolic or toxic encephalopathies. In one patient i.v. administration of 10 mg diazepam did not modify this cortical potential and did not reverse the clinical manifestations. In all patients the only abnormal laboratory finding was an increased level of venous ammonemia. Our findings are against an epileptic origin of VPA encephalopathy and provide further argument in favour of a cortical non-epileptic mechanism mediating negative myoclonus. Benzodiazepines should be avoided in the management of this condition.

Video-polygraphic analysis of myoclonic seizures in juvenile myoclonic epilepsy.

We studied myoclonic seizures (MS) in 5 patients with juvenile myoclonic epilepsy (JME) using video polygraphic recordings to investigate the clinical characteristics of MS in this epileptic syndrome. The total number of MS analyzed was 302 (range 27-125, mean 60) seizures per patient. MS occurred either singly or repetitively (37 vs. 63%) and corresponded to generalized bilaterally synchronous single or multispike-and-wave complexes at 3-5 Hz. Video analysis of the myoclonic jerks demonstrated that either distal or proximal muscle involvement predominated. In the former, there was mild bilateral flexion and some external rotation of the forearms. In the latter, flexion of both arms at the elbow, flexion and abduction of the thighs, and extension of the back was observed. Asymmetry of MS was noted in 4 of 5 patients. Facial involvement of MS occurred infrequently in 2 patients. When the patients kept both arms outstretched, the arms dropped or there was sudden interruption of ongoing electromyographic (EMG) potentials immediately after myoclonic jerks (postmyoclonic inhibition) in all patients. One should inquire about these clinical characteristics of MS in JME when taking a thorough history in patients with primary generalized tonic-clonic seizures (GTC).

Electroencephalographic features of epileptic drop attacks and absence seizures: a case study

A study of epileptic drop attacks (EDA) by simultaneous video-polygraphic recordings was carried out in one epileptic patient with myoclonic astatic seizures (Doose syndrome). EDA was shown to correspond to a burst of generalized bilaterally synchronous spike and wave complexes (GBSSW) at 3 Hz. Absence seizures were also observed with a burst of GBSSW with similar characteristics. The amplitudes of the corresponding slow wave component of GBSSW among the three intensities of atonia, i.e. complete atonia, minor atonia and no discernible atonia (control), was compared. A high amplitude was demonstrated to correspond with more pronounced atonia and a lower amplitude with reduced or absent atonia. These findings suggest that EDA corresponding to GBSSW have a neurophysiological mechanism in common with absence seizures, and that if the GBSSW is intense, it may be sufficient to cause immediate loss of global muscle tone.

Paroxysmal periodic motor attacks during sleep: clinical and polygraphic features

Three patients complained of paroxysmal motor attacks during sleep. Videopolygraphic recordings showed that motor activity could be divided into events of increasing behavioural complexity. Simpler motor events often represented the initial fragment of more complex attacks. Clinical features suggested the attacks represented frontal lobe epileptic seizures. The attacks recurred during NREM sleep with a periodic repetition every 20–60 sec. This periodicity could be related to the analogous physiological oscillation during light sleep and the periodicity of K complexes, exerting a facilitating influence upon epileptic mechanisms.