Interictal EEG Potentials and Epileptogenesis
Although a distinctly appearing EEG-recorded clinical seizure is a most useful event for the clinician, in practice interictal epileptiform potentials are far more commonly encountered. These, therefore, have demonstrated principal usefulness in the diagnosis and classification of an epileptic condition. The usefulness of such interictal spikes has several requisites i they must occur, ii the recording apparatus must be able to detect them, iii visual or automated means must recognize them, iv...
Benign Paroxysmal Vertigo of Childhood
This is the most common of the migraine equivalents 116 . Although affected preschool children are often referred to as having epilepsy, the characteristic history of anxious arrest of movement without loss of awareness and subjective vertigo or drunking makes the diagnosis easy. A related migraine equivalent, benign paroxysmal torticollis of infancy, has been discussed under Paroxysmal Disorders of Movement. Case study 7. A 2-year-old girl had a 6-month history of episodes in which she had...
Tonic Reflex Seizures in Early Infancy
A recent publication 146 has highlighted the occurrence of a new form of nonepileptic seizure in the first 3 months of life. Episodes of sudden stiffening occurred in wakefulness in otherwise normal children and were almost exclusively precipitated by holding the infant upright in a vertical posture. The stiffening lasted for a few seconds and was accompanied by apnea and cyanosis, often followed by crying. Whether this is completely different from the awake apnea of gastroesophageal reflux 61...
Induction Of Episodes
It is useful to attempt the induction of an episode. This process begins by asking the patient or observers what conditions were present at the onset of the attack. These conditions should then be replicated if possible. If an attack occurred upon assuming the upright position or tilting the head back and to the left, the patient should be asked to do so in clinic. A diagnosis of orthostasis or vertigo, respectively, may emerge. Anxiety attacks related to phobias occasionally can be...
Infantile Seizures
A number of investigators have attempted to classify infantile seizures. While no universally accepted infantile seizure classification system yet exists, the unique seizure symptomotology of infants is now recognized TABLE 6.4 Infantile Seizure Semiology Tonic posturing Symmetric asymmetric Clonic jerking Unilateral bilateral Astatic seizures Hypomotor seizures Myoclonic jerks Versive seizures Infantile spasms Table 6.4 . Infantile seizure semiology includes the following 1. Tonic posturing....
Electrodiagnostic Monitoring
The routine EEG is useful for diagnosing spells, but the interpretation of the EEG must be cautious. Many normal variants, such as asymmetrical vertex waves, wicket spikes, small sharp spikes, 14- and 6-per second positive spikes, and rhythmical temporal theta bursts of drowsiness formerly called psychomotor variant , can be mistaken for interictal spikes and sharp waves 109 and see Chapter 1 . Additionally, a few percent of the normal American population exhibit interictal epileptiform...
Benign Neonatal Sleep Myoclonus
Repetitive myoclonic jerks occurring during non-REM sleep constitutes a well-described clinical phenomenon. The myoclonic jerks usually begin in the first few weeks of life and resolve by 2 to 3 months. The jerks are typically bilateral and symmetric, involving the arms and legs. However, focality and migration of the myoclonus among different muscle groups has been noted. The EEG and neurologic outcome is normal. The jerking can be significantly repetitive so as to mimic clonic seizures....
Paroxysmal Movement Disorders
A complex relationship exists between epilepsy and movement disorders, the boundaries of which are difficult to define 101 . They share many symptoms and are frequently confused with each other. Paroxysmal movement disorders are characterized by a variable duration of motor symptoms, usually with few if any interictal abnormalities on examination. Some children with intermediate exertion-related dystonia have subtle dystonia or signs of developmental dyspraxia, even on good days. The major...
Affective Seizures
Any emotion can be expressed during the course of an epileptic seizure 2.2.2.1 . Irritability, anxiety, and anger can occur from amygdalar seizures or stimulation 46,48 . Fear is commonly a component of hippocam-pal seizures 90 . It is often without content and thus takes on the perception of unreality 91 . An affectless expression of fear can occur with cingulate seizures, as can a feeling of happiness 64,71 . Auras may involve the sudden onset of overwhelming fear without dependence on the...
Warren T Blume MD FRCPC
his chapter reviews data pertaining to the place of scalp electroencephalography EEG in the diagnosis and differential diagnosis of paroxysmal conditions epileptic and nonepileptic affecting central nervous system CNS function. The prominence of this role hinges on the relative advantages and disadvantages of EEG and the appropriateness of its employment. EEG discloses function and dysfunction directly, as opposed to neuroimaging, in which dysfunction is only implied from structural...
Linda Laux MD Douglas R Nordli Jr MD
eonates and infants may exhibit a wide variety of paroxysmal episodes that markedly differ from those encountered in older children and adults. These differences relate to the immaturity of the nervous system, which impacts upon the nature of the paroxysmal attacks in several ways. Neonates and infants are more susceptible to imbalances in autonomic control and may, for example, have apnea and syncope spontaneously, or in response to minor provocation. The repertoire of possible movements is...
Painful Seizures
Ictal pain has been recognized as a manifestation of seizure onset within the parietal lobes 88-92 . If ictal pain occurs unilateral in a dermatomal distribution, it localizes to the contralateral postcentral area 88,92 . Ictal pain not uncommonly also occurs in the abdominal region 92 . Pain can be the only manifestation of seizure activity 90 , but it is usually a distinct, brief, and localized sensation. Pain was frequently noted in nonepileptic seizures in the Cleveland Clinic series, but...
Pallid Syncope
Pallid syncopal events are similar to breath holding spells. Again, events are typically precipitated by minor injury, frustration, or fright. Instead of significant crying and cyanosis, the child becomes pale and then loses consciousness. If the events are prolonged, tonic stiffening may be seen. The pathophysiology is secondary to a brief bradycardia or asystole resulting in decreased blood flow and the subsequent facial pallor. Atropine has reportedly been of benefit in decreasing the...
Pitfalls In Diagnosis Of Epilepsy
When epilepsy presents in a classical fashion, with recurrent complex partial or tonic-clonic seizures, accompanied by interictal epileptiform EEG patterns, TABLE I-4 Pitfalls in Diagnosis of Epilepsy Obtaining an inadequate history Overemphasizing the rare and obscure Leading the patient to an inaccurate history Mixed seizures and psychogenic seizures Over-reading the EEG Overinterpretation of a therapeutic trial Incorrect attribution of causation the diagnosis is easy. Unfortunately, the...
Catatonia
The diagnostic criteria for catatonia are waxy flexibility, mutism, negativism, and cataplexy DMSV 119 . These symptoms may be mimicked by the ictal state. Case Study 15. The patient in Figure 3.6 is a 17-year-old male admitted for video-EEG monitoring for paroxysmal episodes of darkening of vision, red or bright flashes, and amnesia. Video-EEG showed concomitant eye fluttering, lip smacking, and catatonic posturing with the left arm flexed and raised in the air as if being held up with the...
Dystonic Drug Reaction
Dystonia is a sustained abnormal posture that occurs from the contraction of both the agonist and antagonist muscle groups of an extremity. Dystonic postures may be generalized or focal. Spells of paroxysmal dystonias are difficult to differentiate from tonic seizures. In infants, a common etiology of sudden dystonia is an acute drug reaction. These reactions may manifest themselves as opisthotonic posturing, torticollis, and an ocu-logyric crisis. Metoclopramide, a parasympathomimetic drug...
Robert T Wechsler MD PhD and Robert S Fisher MD PhD
he patient with a spell of altered sensorimotor function, consciousness, or behavior presents a major diagnostic challenge, because the differential diagnosis is broad, the history is frequently sketchy, and the physical examination often is noncon-tributory 1,2 . Under these conditions, the clinician must be able to recognize certain patterns from fragmentary clues. These patterns will point to a likely etiology for the episode and give a sensible structure to further evaluation. Terminology...
Ictal Behavior Originating in the Frontal Lobes
Frontal lobe seizures are frequently mistaken for psy-chogenic seizures as they do not necessarily impair consciousness and often have very emotional or sexual Lateral anatomy of the brain with correlation to certain seizure types. content 12-14 . Early descriptions of frontal lobe epilepsy often included patients who were psychiatri-cally treated for years 13,15 . Functionally and anatomically, the frontal lobes are often divided into the following regions Figures 2.2 and 2.3 primary motor...
References
1. Cascino GD. Complex partial seizures. Clinical features and differential diagnosis. Psychiatr Clin North Am 1992 15 373-82. 2. Morrell MJ. Differential diagnosis of seizures. Neurol Clin 1993 11 737-54. 3. Oxman TE, Rosenberg SD, Schnurr PP, Tucker GJ, Gala G. The language of altered states. J Nerv Ment Dis 1988 176 401-08. 4. Kapoor WN. Current evaluation and management of syncope. Circulation 2002 106 1606-09. 5. Antzelevitch C, et al. Brugada syndrome 1992-2002, a historical perspective....
References Fqn
1. Martin JB, Reichlin S, Brown GM. Clinical Neuroendocrinology. Philadelphia FA Davis, 1977 129-45. 2. Parker D, Rossman L, Vanderlaan E. Sleep-related, nyctohemeral and briefly episodic variation in human plasma prolactin concentrations. J Clin Encrinol Metab 1973 36 1119-24. 3. Sassin J, Frantz A, Weitzman E, Kapen S. Human prolactin 24hour pattern with increased release during sleep. Science 1972 177 1205-07. 4. Kim KS, Pae CU, Chae JH, Bahk WM, Jun TY, Kim DJ, Dickson RA. Effects of...
Negative Epileptic Seizures
Negative seizures Negative my oclonic-1.1.2.1 atonic-1.1.4 astatic-1.1.5 are clinically defined as a lapse in activity including attention, tone, speech, and sensation 10 . Negative seizures characterized by a fall or a head drop, in the absence of a motor phenomenon such as a convulsion, are broadly classified as falling seizures, drop attacks, or by the terminology proposed by the ILAE 1 . These can be of partial or generalized onset and have been given many terms in the literature including...
Familial Rectal Pain Syndrome
Although the curiously named familial rectal pain syndrome is without doubt very rare, we have had clinical contact with three families and made or seen ictal video-recordings of three children and one adult, supporting the suggestion that this unpleasant disorder is also underdiagnosed 75 . Familial rectal pain syndrome is dominantly inherited, but apparently sporadic cases occur. The presenting feature is dramatic neonatal seizures. Schubert and Cracco 76 thought these might be epileptic...
Raised Intracranial Pressure Attacks
Pyogenic meningitis must be mentioned here because the tonic or vibratory nonepileptic seizures that accompany brain swelling as in Hemophilus influenzae meningitis were often misdiagnosed as epilepsy and treated with repeated injections of diazepam with disastrous results e.g., 1 , case 15.46 . Although immunization should now prevent serious hemophilus infections, the situation of brain swelling and herniation is by no means confined to this disorder and can be seen with any acute rise in...
Urinary Incontinence
Urinary incontinence can be seen in frontal lobe seizures if the frontal cortical representation of the bladder is involved in seizure activity. This can occur without secondary generalization, but does not have a definite localizing value, because this may also be seen in temporal lobe seizures. Urinary incontinence is not a definite proof of an epileptic event, because 44 of patients with nonepileptic psychogenic seizure reported urinary incontinence with their events 43 . Ictal urinary urge...
Shuddering Attacks
Shuddering attacks may begin in infancy, as early as 4 months, or in childhood. The events consist of a rapid tremor of the head, shoulder, and trunk suggestive of the shuddering episodes from a chill. The duration of the events is brief, lasting only seconds, but the events may occur multiple times a day. The spells are often associated with eating and may represent a pattern of stimulation overflow in a young child. The electro-graphic pattern during these spells is normal. No other...
Monisha Goyal MD Paul Zarkowski MD Barbara E Swartz MD PhD
he word seizure typically invokes a mental picture of a confusional or tonic-clonic event. However, a myriad of epileptic seizure phenotypes are not easily identified and often misdiagnosed as nonepileptic events. These epileptic seizure manifestations involve the motor system having bizarre postures or stereotypies , the autonomic system, the somatic and special senses, and the cognitive and psychiatric domains. The stereotyped nature of these events and a high index of suspicion can help lead...
Ictal Behavior Originating In The Temporal Lobes
Epileptologists often divide the temporal lobe into the mesial temporal structures, the lateral neocortex, and the insula. The mesial temporal structures include the hippocampus proper, the amygdala anterior to the hippocampus, the uncus, and the parahippocampal gyrus Figures 2.3 and 2.6 . The lateral temporal cortex includes Heschl's gyrus as the primary auditory area and Wernicke's language area, responsible for receptive language Figure 2.3 . The insula is usually not accessible to epilepsy...
Rem Behavior Disorder
The second sleep disorder that may mimic convulsive epileptic seizures is REM behavior disorder RBD 58,59 . RBD is characterized by recurrent episodes of vigorous motor activity occurring during REM sleep, movements that often awaken the patient or spouse. The primary presenting complaints are interrupted sleep or injuries during sleep. RBD is more common in older adults, usually beginning after the age of 50. It is two to five times more common in men than in women. It is possible that rare...
SleepWake Transition Disorders
Rhythmic movement disorders such as nocturnal head banging jactatio capitis nocturna , body rocking, and head rolling typically occur in infants and toddlers as they are trying to fall asleep. They can be present in deep sleep and in wakefulness. They are more common in children with learning disabilities. They typically remit by 5 years of age, but may persist into adult life. Management relies on good sleep hygiene and padding the headboard so the rest of the house is not wakened. Rhythmic...
Sandifer Syndrome
Infants with gastroesophageal reflux may have intermittent paroxysmal spells of generalized stiffening and opisthotonic posturing. These spells may also be associated with apnea, staring, and minimal jerking of the extremities. A careful history will reveal that these spells are associated with feedings, often occurring within 30 minutes of a feed. Sandifer syndrome can be seen in neurologically normal children as well as children with hypotonia and tracheomalacia, which may predispose the...
Somatosensory Seizures
Parietal lobe seizure can be preceded by an aura of somatosensory sensations. These consist usually of tingling or numbness, or at times as a sensation of movement 6 . More complex sensory sensations are rare. The somatosensory sensation is generated in the postcentral gyrus Brodman areas 1,2,3 and follows a somatopic representation comparable to the somato-topic representation in the precentral cortex. The somatosensory disturbance occurs contralateral to the side of seizure origin 47,84 but...
Visual Seizures
Because most of the occipital lobe is involved in visual function, occipital lobe seizures are frequently preceded by a visual aura. Visual auras include ictal amaurosis or hemianopsia, elementary or complex visual hallucinations, and visual illusions 85,94 . Ictal amaurosis describes ictal blindness and is uncommon. It may be preceded by ictal hemianopsia. If hemianopsia occurs, it has lateralizing significance to the contralateral occipital lobe. Ictal amaurosis lasts seconds to minutes and...
NonREM Partial Arousal Disorders Arousal Parasomnias Night Terrors
Brief nocturnal arousals are normal in children. They occur typically in stage 4 non-REM sleep, 1 to 2 hours after sleep onset. They vary from normal events such as mumbling, chewing, sitting up, and staring to arousals that can be thought of as abnormal because of the disruption they cause the family. These include calm and agitated sleepwalking, and a spectrum from confusional arousals to night terrors or pavor nocturnus. The child may exhibit automatic behavior, but the events are not truly...
Conversion Disorder
Whether the term hysteria should be used is debated but self-induced nonepileptic, nonsyncopal seizures are not rare 7 . Such episodes are called by various names, such as pseudoseizures, pseudoepileptic seizures, psy-chogenic nonepileptic seizures, nonepileptic attack disorder, or emotional attacks none of these terms is satisfactory for every case. The sort of episodes described may crudely mimic epileptic seizures and have some resemblance to certain frontal lobe epileptic seizures but often...
Neonatal Seizures
Recognition of neonatal epileptic seizures is problematic. Initially, the diagnosis and delineation of neona Nonepileptic Spells in Neonates and Infants tal epileptic seizures was based on a clinical description of a paroxysmal event. However, subsequent studies of neonatal seizure evaluation with long-term electroencephalography EEG disclosed that some of these clinical seizures do not have a consistent elec-trographic ictal scalp correlate. This is particularly the case for subtle seizures...
Sensory Seizures
Sensory seizures 2.2 Non-Motor - 2.0 are difficult to define in children because of lack of overt ictal behavior and a child's often limited ability to communicate the experience. Patients may complain of tingling, numbness, pain, heat, cold, or electric shock sensations. The case illustrates a simple partial seizure initially thought to be a migraine variant and subsequently attention-seeking behavior. Case Study 5. A 6-year-old boy complained of pulsations in his head up to several times a...
Slow Delta Wave Activity Hepatic Encephalopathy
___ he diagnosis of paroxysmal events in I the elderly presents particular difficulties, especially when contrasted with the problem presented by younger patients. In the first instance, the history is often difficult to obtain, vague, or not available at all. A second problem, common in the elderly, is the coexistence of multiple medical and or neurological problems that complicate the analysis of intercurrent paroxysmal symptoms. A third factor involves the confounding results of diagnostic...
Discussion 1
Syncope is usually defined as a transient loss of consciousness accompanied by a loss of postural tone 9-11 . This definition, emphasizing two common clinical features of syncope, allows one to develop a differential diagnosis and to pursue a work-up based on the observed phenomena. On the other hand, Lempert defines syncope as a transient loss of consciousness and upright posture due to global cerebral ischemia 12 . There are two major advantages to Lempert's definition i it limits syncope to...
References Xgv
1. Blume WT, Luders HO, Mizrahi E, et al. ILAE Commission report. Glossary of descriptive terminology for ictal semeiology Report of the ILAE task force on classification and terminology. 2001 Epilepsia 42 9 1212-18. 2. Rufo-Campos M, Gonzalez M-L A, Rangel-Pineda C. Cerebral seizures in neonatal period semeiology, evolution and factors of influence. Rev Neurol 2000 31 4 301-6. 3. Liporace J, Sperling M. Simple autonomic seizures. In Engel J, Pedley TA eds. Epilepsy a Comprehensive Textbook....
Hyperventilation Syncope
Hyperventilation in any human induces various organic symptoms that may in certain individuals stimulate further hyperventilation and exacerbation of the original symptoms. A degree of panic may be so engendered. Asking the child to hyperventilate whether by getting the child to repeatedly blow out a candle, blow soap bubbles, blow a tissue, or to directly hyperventilate may induce symptoms similar to those of which the child complains. Continuation of hyperventilation once the directed...
Hyperkinetic Seizures
Video-EEG has familiarized most neurologists with the fencing or M2e postures of supplementary motor The figure demonstrates a young girl who loses motor control of her right hand during seizures reproduced from video . The EEG of the event indicated at vertical line did not show a clear ictal build-up but demonstrated epileptiform potentials at Cz-Pz arrow during the event. On this and subsequent EEG figures, the calibration bar indicates 50 V, the green vertical line corresponds to the time...
Hyperekplexia 1
Hyperekplexia is a rare disorder or group of disorders that may include dramatic neonatal onset 68 with nonepileptic convulsive syncopes that may prove fatal. Insofar as effective treatment is possible by repeatedly flexing the baby 69 , diagnostic awareness should be high. An early major paper on this topic 70 described a dominantly inherited disorder in which there were stiff hypertonic neonates with later pathologic startles. Some confusion has been engendered by the title of this first...
Paroxysmal Torticollis
Torticollis is an abnormal sustained posture of the head and neck in which the head tilts to one side and the face rotates to the opposite side. In paroxysmal torticollis, the events begin and end suddenly. The attacks can be brief or prolonged. The child is alert and responsive during an attack although the patient may appear uncomfortable and irritable. The EEG is normal during the event. The etiology of the attacks is unknown, although both a focal dystonia and labyrinth dysfunction have...
Mesial Temporal Lobe Seizures
Mesial temporal lobe seizures are by far the most common seizures originating within the temporal structures and are the single most common seizure type seen in the adult population. They represent the typical complex partial seizure. Mesial temporal lobe seizure are often preceded by an aura, which not uncommonly also occurs in isolation 54,55 . The most common aura are epigastric sensations or abdominal auras, which the patient often describes as a rising sensation, nausea, butterflies in the...
Nonepileptic Seizures And Paroxysmal Nonepileptic Events In The Population
The diversity of nonepileptic events in childhood and adolescence is very considerable. Some of these nonepileptic events fully justify the term nonepileptic seizure 1,2 . It is our impression that the most common type of nonepileptic seizure leading to diagnostic confusion in clinical practice is the anoxic seizure, or synco- pal convulsion 3 . This view is supported by recent observational studies 4,5 . It is also our clinical impression that misdiagnoses of epilepsy are more likely to arise...
AnoxicEpileptic Seizures
In the past 40 years, those who have paid close attention to the mechanisms of seizures have recognized that the common motor seizure that is a manifestation of severe convulsive syncope is a nonepileptic seizure, the so-called anoxic seizure see Syncopes and Anoxic Seizures . Many comments in the literature suggest that it is common knowledge that severe anoxia produces epileptic convulsions, or even specifically tonic-clonic epileptic seizures, but, in fact, such remarks have until recently...
Reflex Epilepsies
Reflex epilepsies are usually discussed in association with unusual epileptic seizure types. However, the seizures themselves are less unique than the fact that specific stimuli trigger them. If seizures do not exist in the absence of the triggers, some argue that these are not real epilepsies 82 , but rather, that the term reflex should be considered a seizure modifier. An example of a reflex epilepsy is musicogenic epilepsy 83-85 , in which music may trigger a seizure with musical...
Conclusion Hzu
Numerous and varied paroxysmal spells in neonates and infants may be nonepileptic in nature. The knowledge of typical epileptic and nonepileptic events in neonates and infants will aid the clinician in the correct diagnosis. The most important tool in determining epileptic from nonepileptic events is a careful clinical history. However, if the history does not disclose the diagnosis, a videotape of the event or a concomitant video-EEG recording may be helpful 28-30 . Neonatal and infant...
DecorticateDecerebrate Posturing
Decorticate and decerebrate posturing can mimic tonic seizures. Decorticate posturing refers to flexor posturing of the upper extremities and extensor posturing of the lower extremities. In decerebrate posturing, both the upper and lower extremities show extensor stiffening. Both events can occur suddenly from a severe brain injury affecting the brainstem level. This posturing can be seen bilaterally or unilaterally in different herniation syndromes. Possible impending herniation should be...
Focal Clonic Seizures
Focal clonic seizures consist of the rhythmic jerking of unilateral muscle groups without impairment of consciousness. Clonic motor seizures originate in the primary Mesial anatomy of the brain with correlation to certain seizure types. motor cortex Brodmann area 4 contralateral to the motor activity. The muscle groups that are involved strictly follow the cortical motor representation homunculus, Figure 2.4 . As face and hand have the biggest cortical representation, they are the most commonly...