Childhood epilepsy with occipital paroxysms and benign nocturnal childhood occipital epilepsy

Two types of childhood epilepsy have recently been reported: childhood epilepsy with occipital paroxysms, and benign nocturnal childhood occipital epilepsy. This article reports the clinical evolution, electroencephalographic (EEG) changes, and response to therapy of eight children with childhood epilepsy with occipital paroxysms (five boys and three girls, aged from 1 1/12 to 8 years) and eight children with benign nocturnal childhood occipital epilepsy (six boys and two girls, aged from 1 4/12 to 8 3/12 years). A careful clinical and EEG follow-up of at least 7 years was carried out for all patients. At the end of follow-up, all but one of the patients with childhood epilepsy with occipital paroxysms were seizure-free, and only two were still receiving anticonvulsant drugs. All but three children had a normal EEG, and normal mental development was observed in all but two cases. Patients with benign nocturnal childhood occipital epilepsy had a good long-term prognosis; all but two children with benign nocturnal childhood occipital epilepsy had a normal EEG. These two patients showed learning disabilities and poor school performances, and required remedial education. Therefore, although childhood epilepsy with occipital paroxysms and benign nocturnal childhood occipital epilepsy are two different types of epilepsy, the long-term prognosis seems to be similar.     

Pure alexia for kana. Characterization of alexia with lesions of the inferior occipital cortex

OBJECTIVE: To characterize reading impairments caused by lesions in the posterior occipital cortices. METHODS: We gave six patients with these lesions reading and writing tests and located a critical site for alexia using MRI and SPECT. RESULTS: The patients read three-character kana (Japanese syllabograms) nonwords, and five-character kana nonwords significantly or at a near significant level more poorly and slowly than normal subjects, whereas they read kanji (Japanese morphograms) almost correctly but more slowly. Letter-by-letter reading with a single-kana character identification impairment (in five patients), a word-length effect, kinesthetic facilitation, a lexicality effect, and minor to mild agraphia for kanji (in three patients) were observed. These deficits were characteristic of pure alexia. Alexia disappeared within a few months except in one patient who had extensive hypoperfusion in the left occipital lobe. A shared lesion was located in the left posterior fusiform/inferior occipital gyri (Area 18/19) on MRI, and there was blood flow reduction around this area on SPECT. This area coincided with the activation site for kana word covert reading in our previous study. CONCLUSIONS: These results suggest that pure alexia particularly for kana, or more generally pure alexia for letters, is caused by a lesion in the posterior inferior occipital cortex, characterized primarily by impaired kana character or letter identification, with relatively preserved kanji or word recognition.     

Ictal perfusion changes during occipital lobe seizures in infancy: report of two serial ictal observations

Serial-ictal single-photon-emission computed tomography (SPECT) examinations are presented in two infants (ages 1 and 2 years), with early ictal and ictal in one, and ictal and late ictal images in the other. Both had pharmacoresistant occipital epilepsy, due to focal cortical dysplasia. In the first case, size of ictal hyperperfusion increased in the course of the seizure from early ictal to ictal state. A concomitant ictal hypoperfusion was observed around the hyperperfused area. In the second patient, there was a dramatic difference between ictal and late ictal images. In the late ictal state, the previous occipital ictal hyperperfusion and extraoccipital ictal hypoperfusion disappeared, together with homolateral posterotemporal and contralateral occipital hyperperfusion, corresponding to seizure propagation. Ictal extratemporal blood-flow changes are therefore highly dynamic, particularly in very young children.     

Ictal SPECT and interictal PET in the localization of occipital lobe epilepsy

PURPOSE: To compare the localizing value of ictal single photon emission computed tomography (SPECT) and interictal fluorodeoxyglucose-positron emission tomography (FDG-PET) in refractory occipital lobe epilepsy. METHODS: Six patients who underwent surgery for refractory epilepsy associated with pathology in the occipital lobe were retrospectively selected from records of the Austin & Repatriation Centre Comprehensive Epilepsy Programme. Interictal SPECT and PET and ictal SPECT were obtained by standard methods. All studies were read by a nuclear medicine expert blinded to clinical data except the diagnosis of epilepsy. RESULTS: Ictal SPECT showed unilateral occipital hyperperfusion in five of six cases often accompanied by temporal lobe hyperperfusion. These patterns were seen in cases with or without magnetic resonance imaging (MRI) abnormality. Interictal SPECT was not localizing in any case, in contrast to PET, which showed occipital hypometabolism in three of five studies. CONCLUSIONS: Ictal SPECT can provide novel localizing data in MRI-negative occipital lobe epilepsy. Interictal PET can provide useful localizing information, but its role in providing novel information was not demonstrated. Interictal SPECT is useful only as a baseline to aid in interpretation of ictal studies.     

Siblings with refractory occipital epilepsy showing localized network activity on EEG‐fMRI

The benign occipital epilepsies of childhood include Panayiotopoulos and Gastaut syndromes; a third syndrome, idiopathic photosensitive occipital epilepsy may also begin in childhood or adolescence. We describe siblings with occipital epilepsy characterized by refractory, frequent, brief visual seizures and normal magnetic resonance imaging (MRI). Electroencephalography (EEG) with functional MRI (fMRI) supports localization of interictal epileptiform activity to the occipital lobes. Our hypothesis is that the siblings share a genetic focal epilepsy arising from a localized occipital network. Although they share many features of Gastaut syndrome, their refractory ongoing seizures in adolescence is unusual and likely due to underlying genetic determinants.     

Benign childhood epileptic syndromes with occipital spikes: new classification proposed by the International League Against Epilepsy

In a recent proposal, the Commission on Classification and Terminology of the International League Against Epilepsy recognized early-onset childhood epilepsy with occipital spikes (Panayiotopoulos type), differentiating it from the only other type of childhood epilepsy with occipital spikes previously accepted: late-onset childhood epilepsy with occipital spikes (Gastaut type). The importance of this newly recognized syndrome of benign childhood partial seizures is that it is very common-only 2.4 times less frequent than benign rolandic epilepsy, and of equally excellent prognosis. It is characterized by a unique seizure type comprising a combination of autonomic and behavioral disturbances, vomiting, deviation of the eyes, and often with impairment of consciousness that can progress to convulsions. These commonly last for more than 3 minutes and in one quarter of cases for hours. One or more of these symptoms can predominate or be absent. Eyes can remain open without deviation, ictal vomiting might not occur, and autonomic and behavioral disturbances can predominate, particularly in the early stages of the ictus, and be missed in nocturnal seizures. Age at onset is 5 years, with a singular or a median of three seizures, which are predominantly nocturnal. Interictal electroencephalography (EEG) frequently shows occipital paroxysms or occipital spikes but one-fifth of the cases have only extraoccipital spikes on normal EEG. Treatment might not be needed. Panayiotopoulos syndrome, like rolandic epilepsy, needs recognition by the general pediatrician because of the invariably excellent prognosis and also because it can be misdiagnosed as an acute cerebral insult.     

Usefulness of a blood flow analyzing program 3DSRT to detect occipital hypoperfusion in dementia with Lewy bodies

In the latest criteria for the clinical diagnosis of dementia with Lewy bodies (DLB), supportive features include generalized low uptake on SPECT/PET perfusion scan with reduced occipital activity. In this study, we investigated the usefulness of a cerebral blood flow (CBF) quantification program '3DSRT' in detecting occipital hypoperfusion in DLB. Twenty two patients with probable DLB, 38 patients with probable Alzheimer's disease (AD) and 16 normal controls underwent brain perfusion SPECT. Compared with AD, DLB patients had a bilateral lower CBF in the posterior cerebral segments. The correlation of clinical symptoms and brain blood perfusion was examined by dividing the subjects into subgroups. DLB patients with Parkinsonism, when compared to non-Parkinsonism subgroup, had a lower CBF throughout the cerebrum with statistical significance in the posterior cerebral segments. The quantitative analysis of brain perfusion SPECT by 3DSRT could be a useful supportive measurement in the diagnosis of DLB.     

Panayiotopoulos-type benign childhood occipital epilepsy: a prospective study

OBJECTIVE: To characterize the clinical and EEG features of the syndrome of benign childhood partial seizures with ictal vomiting and EEG occipital spikes (Panayiotopoulos syndrome [PS]). METHODS: Prospective study of children with normal general and neurologic examinations who had seizures with ictal vomiting and EEG with occipital spikes. RESULTS: From February 1990 to 1997, the authors found 66 patients with PS and 145 children with benign childhood epilepsy with centrotemporal spikes. Peak age at onset of PS was 5 years. Ictal deviation of the eyes and progression to generalized seizures were common. One-third had partial status epilepticus. During sleep, all had seizures. While awake, one-third also had seizures. Five children with PS had concurrent symptoms of rolandic epilepsy and another five developed rolandic seizures after remission of PS. Prognosis was excellent: one-third had a single seizure, one-half had two to five seizures, and only 4.5% had frequent seizures. CONCLUSIONS: Panayiotopoulos-type benign childhood occipital epilepsy is less common than benign childhood epilepsy with centrotemporal spikes but is well defined and recognizable by clinical and EEG features.     

Autism and autistic epileptiform regression with occipital spikes

The electroencephalographs abnormalities seen in Landau-Kleffner syndrome (LKS) (language deterioration) are non-specific, and consist of a variety of epileptiform discharge patterns including continuous slow spike-wave discharges during sleep, focal sharp waves with spikes, and centrotemporal (rolandic) spikes. Similarly, the EEG abnormalities seen in autistic epileptiform regression (language and social/behavioral deterioration) are nonspecific and overlap with those seen in LKS. By contrast, distinct epilepsy syndromes in otherwise normal children occur in the EEG-deflned benign focal epilepsies of childhood. Occipital spikes or spike-wave present either in the older child with visual symptoms and headache or in the younger child with autonomic symptoms followed by brief or prolonged partial motor seizures. Seven young children (five from a consecutive series of 42) presenting clinically with autism or autistic regression and possible or definite seizures, whose EEGs revealed occipital spikes or spike-wave characteristic of the benign epilepsies, are reported. Although occipital spikes are commonly seen in young children as an age-dependent EEG-defined benign focal epilepsy, their high frequency in this population with cognitive difficulties suggests a possible causal relation. The effects of the epileptiform discharge on cognitive functioning presumably reflect extension into temporal and parietal lobes, rather than occipital disturbances per se.     

Deep gray matter hyperperfusion with occipital hypoperfusion in dementia with Lewy bodies

Although decreased occipital perfusion is a characteristic feature of dementia with Lewy bodies (DLB), not all patients with DLB show a significant decreased perfusion in the occipital lobe. We explored characteristics of perfusion changes to improve the identification of DLB, in addition to occipital hypoperfusion. Statistical image analysis of single photon emission computed tomography data was performed on 22 patients with DLB and 25 patients with Alzheimer's disease (AD). A significant decreased perfusion in the occipital lobe was found in 16 patients with DLB (72%) and three patients with AD (12%), while a significant increased perfusion in the deep gray matter (striatum and/or thalamus) was found in 18 patients with DLB (81%) and eight patients with AD (31%), respectively. Either occipital hypoperfusion or deep gray matter hyperperfusion was found in 21 patients with DLB (95%), while in nine patients with AD (35%), indicating a sensitivity of 95% and a specificity of 65% in discriminating DLB from AD. Our results suggest that the addition of deep gray matter hyperperfusion to occipital hypoperfusion may be useful in the clinical differentiation of DLB and AD.     

Possible involvement of the tip of temporal lobe in Landau-Kleffner syndrome

Landau-Kleffner syndrome (LKS) is a childhood disorder of unknown etiology characterized by an acquired aphasia and epilepsy. We have performed comprehensive neurofunctional studies on an 8-year-old girl with typical LKS, with the aim of identifying lesions that may be responsible for her condition. 18F-fluoro-D-glucose (FDG) positron emission computed tomography (PET), 11C-Flumazenil (FMZ) PET, 99mTc-hexamethylpropyleneamine oxime single photon emission computed tomography (SPECT) and magnetoencephalography were performed before and after changes to the patient's medication led to a clinical improvement. Interictal SPECT showed hypoperfusion in the left frontal, left temporal, and left occipital lobes. 18F-FDG PET demonstrated a decrease in glucose metabolism medially in both temporal lobes and superiorly in the left temporal lobe. 11C-FMZ PET revealed a deficit in benzodiazepine receptor binding at the tip of the left temporal lobe. Magnetoencephalography demonstrated equivalent current dipoles located superiorly in the left temporal lobe. Our results suggest that the tip of the left temporal lobe plays an important role in the pathogenesis of LKS in our patient.     

Abstracts of the 38th Congress of the Japan Epilepsy Society, Shizuoka, Japan, September 30-October 1, 2004

Diagnosis and Treatment of Idiopathic Focal Epilepsies (Benign Partial Epilepsies) in Infancy and Childhood. ¹ Tamiko Negoro ( ¹ Department of Laboratory Medicine, Nagoya University Hospital, Nagoya, Japan ). Introduction: According to the revised classification of epilepsies and epileptic syndromes proposed by the Commission on Classification and Terminology of the International League Against Epilepsy (1989), benign childhood epilepsy with centrotemporal spikes (BCECT), childhood epilepsy with occipital paroxysms (Gastaut‐type late‐onset CEOP), and primary reading epilepsy were included in the idiopathic localization‐related epilepsies (ILRE). Since then, new epileptic syndromes such as Panayiotopoulos‐type early‐onset benign childhood occipital epilepsy (also known as benign childhood epilepsy with occipital paroxysms or BCEOP) and benign partial epilepsies in infancy (BPEI) have been additionally included as ILRE. The diagnostic criteria for benign partial epilepsies include (1) normal neurological examination; (2) normal intelligence; (3) normal neuroimaging; (4) a family history of benign‐type seizures; (5) brief stereotyped seizures; (6) frequent nocturnal occurrence; (7) easy control with antiepileptic drugs (AEDs), except ethosuximide; and (8) remission before adolescence. The EEG features include (1) normal background activity; (2) spikes with a characteristic morphology and location; (3) sleep activation; and (4) occasional generalized paroxysms. In our 114 cases of childhood onset localization‐related epilepsies (LRE) diagnosed between 1997 and 2000, 48 cases (42%) were diagnosed as ILRE and 66 were cryptogenic or symptomatic LRE. Among the 48 ILRE cases, 28 (58%) were classified as BCECT, six (13%) as BPEI, five (10%) as BCEOP, two (4%) as atypical benign partial epilepsy, and seven (15%) as unclassified. Carbamazepine (CBZ), valproate (VPA) and clonazepam (CZP) were equally effective in controlling the seizures in our ILRE patients. This review describes briefly the diagnosis and treatment of BCECT, BCEOP, and BPEI. Benign Childhood Epilepsy with Centrotemporal Spikes: BCECT is the most common ILRE (also known as idiopathic focal epilepsies) in infancy and childhood. Sylvian seizures (simple partial seizures or focal motor or sensory seizures beginning unilaterally at the lower part of the face) and EEG findings (central‐midtemporal high‐amplitude, repetitive sharp waves) are quite stereotyped, and diagnosis of typical cases is relatively easy. Frontal lobe seizures with bilateral perioral twitches or unilateral eyelid twitches may sometimes be misdiagnosed as Sylvian seizures. Since status epilepticus is very rare and many patients only have occasional seizures, many physicians choose not to treat the disorder. If treatment is necessary, the seizures are usually easily controlled with carbamazepine, valproic acid, or clonazepam. Continuation of AEDs is not necessary after the EEG has normalized around puberty. The prognosis is excellent. However, a small percentage of patients may show atypical evolutions such as atypical benign partial epilepsy, epilepsy with continuous spike‐and‐waves in slow wave sleep, or epilepsy with centrotemporal spikes and oromotor deficit. Seizure and EEG exacerbations by AEDs, especially carbamazepine, have to be considered. Early recognition and proper treatment are necessary for these conditions. Benign Childhood Epilepsy with Occipital Paroxysms: BCEOP is also known as Panayiotopoulos‐type early‐onset benign childhood occipital epilepsy. The mean age at first seizure is around 5 years. Seizures comprise an unusual constellation of autonomic, mainly emetic, syndromes with unilateral deviation of the eyes and impairment of consciousness. Visual symptoms, which are the main symptoms in Gastaut‐type, late‐onset CEOP, are exceptions in BCEOP. According to our 41 cases examined between 1984 and 1993, two‐thirds of the patients show hemi‐ or generalized convulsions and one‐fourth experience prolonged seizures for longer than 30 minutes. EEG findings (bilateral occipital paroxysms) consist of some extraoccipital abnormalities especially in the frontal area (48% of our cases) or generalized paroxysmal discharges (32% of ours cases), together with various migrations of spike foci. EEG findings seem to normalize around the age of 10 years. Many patients only have occasional seizures and these seizures are usually easy to control with carbamazepine or valproic acid. The prognosis is excellent. Prevention of status epilepticus is the major problem in this disorder. Recently, new concepts including early‐onset benign occipital seizure susceptibility syndrome (EBOSS) and Panayiotopoulos syndrome (idiopathic susceptibility to early‐onset benign childhood seizures with mainly autonomic symptoms), have been introduced for BCEOP. Benign Partial Epilepsies in Infancy: BPEI comprise two forms. One is partial epilepsy with complex partial seizures (CPS) and the other is partial epilepsy with secondarily generalized seizures (SGS). Onset is mostly during the first year of life. Seizures often occur in clusters and are characterized by motion arrest, decreased responsiveness, staring or blank eyes often with automatisms, and mild convulsive movements in the CPS form; and motion arrest or opening of eyes with staring or blank eyes followed by generalized tonic–clonic seizures in the SGS form. Interictal EEGs mostly show no abnormal findings. According to the ictal EEGs, the most frequent site of seizure origin is in the frontal or temporal area in the CPS form; and central, parietal, or occipital area in the SGS form. Treatment with carbamazepine, phenobarbital, zonisamide or valproic acid immediately stops the cluster of seizures. The prognosis is excellent. Recently, sleep‐related and low‐voltage Rolandic and vertex spikes have been reported as an EEG marker of benignity in this disorder. Most of benign infantile convulsions may belong to partial epilepsy with SGS, although confirmation with ictal EEG recording is necessary for accurate diagnosis.     

Benign childhood epilepsy with occipital paroxysms: neuropsychological findings

Benign childhood epilepsy with occipital paroxysms is classified among childhood benign partial epilepsies. The absence of neurological and neuropsychological deficits has long been considered as a prerequisite for a diagnosis of benign childhood partial epilepsy. Much evidence has been reported in literature in the latest years suggesting a neuropsychological impairment in this type of epilepsy, particularly in the type with Rolandic paroxysms. The present work examines the neuropsychological profiles of a sample of subjects affected by the early-onset benign childhood occipital seizures (EBOS) described by Panayotopulos. The patient group included 22 children (14 males and 8 females; mean age 10.1+/-3.3 years) diagnosed as having EBOS. The patients were examined with a set of tests investigating neuropsychological functions: memory, attention, perceptive, motor, linguistic and academic (reading, writing, arithmetic) abilities. The same instruments have been given to a homogeneous control group as regards sex, age, level of education and socio-economic background. None of the subjects affected by EBOS showed intellectual deficit (mean IQ in Wechsler Full Scale 91.7; S.D. 8.9). Results show a widespread cognitive dysfunction in the context of a focal epileptogenic process in EBOS. In particular, children with EBOS show a significant occurrence of specific learning disabilities (SLD) and other subtle neuropsychological deficits. We found selective dysfunctions relating to perceptive-visual attentional ability (p<0.05), verbal and visual-spatial memory abilities (p<0.01), visual perception and visual-motor integration global abilities (p<0.01), manual dexterity tasks (p<0.05), some language tasks (p<0.05), reading and writing abilities (p<0.01) and arithmetic ability (p<0.01). The presence of cognitive dysfunctions in subjects with EBOS supports the hypothesis that epilepsy itself plays a role in the development of neuropsychological impairment. Supported by other studies that have documented subtle neuropsychological deficits in benign partial epilepsy, we stress the importance of reconsidering its supposed "cognitive benignity", particularly in occipital types.     

Benign osteoblastoma of the occipital bone: Case report and literature review

We present a case of benign osteoblastoma of the occipital bone. Benign osteoblastoma is an uncommon primary bone tumor, which usually involves the vertebrae and the long bones. This tumor rarely develops in the calvaria, showing a preference for the temporal and frontal bones when it does. To the best of our knowledge, this case is only the eighth reported case of benign osteoblastoma confined to the occipital bone. A 20‐year‐old male presented with a mild tender mass lesion of the occipital area, just below the lambda. Plain X‐ray films and CT scans demonstrated an osteolytic mass surrounded by the sclerotic rim within the diploic space. MRI proved to be effective for the evaluation of the intracranial and intraosseous extensions of the tumor. However, it was very difficult to formulate a differential diagnosis against other osteoblastic tumors, or osteoid osteoma, in view of its radiological appearance. The final diagnosis was obtained by careful consideration of the histopathological characteristics of the tumor combined with its clinical and radiological features. Although generally regarded as benign, a complete resection is preferred over conventional curettage as this can guard against possible recurrence and malignant transformation.     

Early-Onset Benign Occipital Seizure Susceptibility Syndrome

Summary: Purpose: Childhood epilepsy with occipital paroxysms (CEOP) is characterised by ictal visual hallucinations and occipital epileptiform activity on interictal EEG. A variant has been described with nonvisual symptoms including tonic head and eye deviation, vomiting, and episodes of partial status epilepticus. We fully documented the electroclinical features of such patients to determine whether classification separate from CEOP is justified.
Methods: This was a multicentre study with participating investigators submitting details of patients with idiopathic occipital seizures characterised by ictal head or eye deviation and vomiting.
Results: One hundred thirteen patients were recruited. Seizures began in early childhood (mean, 4.6 years) and occurred infrequently (mean total seizures, 3); 30% of patients had only a single seizure. Two thirds of seizures were nocturnal. Ictal eye deviation occurred in 79%, vomiting in 70%, and head deviation in 35%. Seizures were predominantly complex partial in type. Partial status epilepticus occurred in 44% of patients. Seventy-four percent of patients had occipital interictal EEG epileptiform activity, predominantly right sided, with fixation-off sensitivity. Extraoccipital EEG abnormalities occurred in 35% of patients. Prognosis was excellent: the mean duration of active seizures was 1 year.
Conclusions: Although the two groups shared identical EEG features, the distinct clinical symptoms probably justify separate classification. Early-onset benign occipital seizure syndrome (EBOSS) is suggested as an appropriate name for the variant group.     

Occipital hypoperfusion on SPECT in dementia with Lewy bodies but not AD

OBJECTIVE: To compare regional cerebral blood flow (rCBF) changes using 99mTc-hexamethylpropyleneamine oxime (99mTc-HMPAO) SPECT in subjects with dementia with Lewy bodies (DLB) and AD and in normal age-matched control subjects; to examine the utility of SPECT changes in the differential diagnosis of AD and DLB. METHOD: Whole-brain SPECT scans were acquired using a single-headed rotating gamma camera (IGE CamStar XR/T) in elderly subjects with consensus criteria DLB (n = 23; mean age = 79.4 years), National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association AD (n = 50; 81.9 years), and normal control subjects (n = 20; 78.1 years) after injection with 500 MBq of 99mTc-HMPAO. Region-of-interest analysis was performed using a SPECT template registered in Talairach space, with rCBF normalized to cerebellum. RESULTS: Both DLB and AD subjects had significantly reduced rCBF in parietal and temporal regions compared with the control subjects. The AD group also showed a significant reduction in rCBF in the frontal and medial temporal regions and the DLB in the occipital areas compared with control subjects. AD and DLB groups differed only in occipital perfusion (p < 0.01). SPECT measures (occipital and medial temporal) correctly classified 69% of all subjects, with a 65% sensitivity and 87% specificity for DLB against AD and control subjects. CONCLUSION: Temporoparietal hypoperfusion on SPECT is common to both AD and DLB. Occipital hypoperfusion is more frequently seen in DLB. Although not diagnostically specific in individual cases, occipital hypoperfusion on SPECT should raise suspicion that DLB may be the cause of dementia, prompting careful search for other features of the disorder.     

Visual evoked potentials in children with occipital epilepsies

The objectives of this study are to see if any visual evoked potential (VEP) differences are present in two forms of occipital epilepsy, childhood epilepsy with occipital paroxysms (CEOP) and symptomatic occipital epilepsy (SOE) with respect to etiology, as CEOP is a benign age- and localization-related idiopathic epilepsy while SOE is a symptomatic form. Nineteen patients with CEOP and 13 patients with SOE were included in the study and P100 potential latency and amplitude values obtained from these patients were compared with the values recorded from normal controls. The amplitude values recorded from the patients with CEOP were significantly high (P=0.033). P100 potential latency values recorded in patients with SOE were significantly long (P=0.028). High amplitude VEP responses were mostly attributed to hyperexcitability of the occipital cortical structures whereas prolonged latency P100 responses were attributed to occipital structural changes.     

Paroxysmal visual disturbances of epileptic origin and occipital epilepsy in children

A special form of partial occipital epilepsy clinically resembling migraine and possibly related to the benign focal epilepsies of childhood has recently attracted attention (Gastaut 1982) but its existence is still debated. To approach this problem, in a group of 195 children with idiopathic partial or generalized epilepsy we have studied those who had visual complaints as part of their seizures (twelve children) and those who also had migraine (four children). The clinical and electroencephalographic features of these children were analyzed together with those of another group of thirty children diagnosed as migraine accompagnée in which an EEG had been obtained (3/30, i.e. 10% had paroxysmal spike-waves: one centrotemporal focus, two generalized spike-waves). One child with the type of epilepsy described by Gastaut (1982) as partial benign occipital epilepsy (phosphenes, moving lights, headaches and occipital high voltage biphasic spike-waves blocked by eye opening on the EEG) was found in the epileptic group whereas the other children of this group, including those with associated migraine, had other types of epilepsy. This "new" type of epileptic syndrome can be distinguished from symptomatically resembling entities but its place needs to be further defined.     

Fixation-off sensitivity in an adult with symptomatic occipital epilepsy

An adult patient had EEG occipital spike fixation-off sensitivity and spontaneous occipital seizures due to perinatal asphyxia with bioccipital hemorrhage. EEG abnormalities consisted of repetitive posterior spikes that occurred when the eyes were closed and other conditions of fixation-off. Magnetic resonance imaging (MRI) documented severe posterior lesions with wallerian degeneration of the optic radiation. Electron capture detector single-photon emission computed tomography (ECD-SPECT) during the state of fixation-off showed regional hyperperfusion in the right posterior regions. We suggest that partial denervation of the primary visual cortex in this patient resulted in an increased cortical excitability and that the inhibitory effect of central vision and fixation leads to a suppression of spontaneous epileptic activity. This unusual symptomatic case may serve as a model for the pathophysiology in the more often reported cases of idiopathic benign epilepsy syndrome of childhood.