Symptomatic Occipital Epilepsy Research Articles

Presentation, Etiology, Outcome, and Differentiation of Visual Semiology of Adult Occipital Epilepsy From Visual Aura of Migraine Headache: A Prospective Study in a Tertiary Care Center in Bangladesh.

Background: Occipital epilepsy is an uncommon and likely underdiagnosed type of epilepsy that is often misdiagnosed as a migraine with aura. High clinical suspicion and subsequent electroencephalogram (EEG) and brain imaging lead to early diagnosis. Methods: We recruited patients with occipital epilepsy based on visual semiology, structural abnormalities in the occipital region, or EEG changes who visited the Department of Neurology of Dhaka Medical College from June 2019 to January 2020. We documented the presentations, etiology, and outcomes at the 12-month follow-up. Additionally, we compared the clinical features of patients with occipital epilepsy (n = 10) and those with migraine with aura (n = 18).Results: We identified three and seven cases of idiopathic and symptomatic occipital epilepsy, respectively, all presenting with visual semiology. Symptomatic occipital epilepsy occurred due to space-occupying lesions, post-hypoxic damage, post-stroke encephalomalacia, gyral calcification from Sturge-Weber syndrome, and Wilson’s disease. Age, sex, illness duration, headache severity, and associated features were similar between the migraine with aura and epilepsy groups. In occipital epilepsy, the median (IQR) age was 22 (15-47) years, and the patients were predominantly female (8, 80%). The visual auras lasted 35 (3-375) seconds and included colored dots or light flashes that persisted for seconds (50%) before (60%), during (30%), and after (10%) the headache. Compared to migraines, the headaches were global (90%), compressive (90%), and of shorter duration (210 minutes, IQR: 150-630). Except for nausea or osmophobia, vomiting (80%), photophobia (80%), and phonophobia (70%) occurred. Most cases had associated focal or bilateral tonic-clonic seizures (60%; p-value < 0.001). In contrast, the visual auras in migraine were scotomas, white or golden dots, or light flashes lasting for minutes (83.3%; p-value = 0.02) before the headache. The headaches lasted longer (720 minutes, IQR: 345-1,440, p-value < 0.03), were unilateral (44%) or bilateral (50%), and throbbing (72%; p-value = 0.003). Headache was associated with photophobia (94.4%; p-value = 0.28), phonophobia (88.9%; p-value 0.31), and osmophobia (38.9%; p-value 0.03); no associated convulsions occurred. At the 12-month follow-up, most occipital epilepsy patients (9, 90%) responded well to carbamazepine.Conclusions: Patients with transient and distinct elementary visual hallucinations headache characteristics different from migraines with associated convulsions warrant evaluation for occipital epilepsy.

Fixation-off sensitivity in a girl with symptomatic occipital epilepsy admitted in non-convulsive status epilepticus

Fixation-off sensitivity in a girl with symptomatic occipital epilepsy admitted in non-convulsive status epilepticus

Amaurosis Fugax Caused by Neurocysticercosis

To The Editors: Neurocysticercosis (NCC) is the most common parasitic disease of the central nervous system caused by the larval stage of the pork tapeworm Taenia solium. We present here an unusual, interesting manifestation of NCC in a young boy as episodic, transient vision loss mimicking a transient ischemic attack. A previously healthy, 11-year-old boy presented with 2 episodes of acute-onset, bilateral, painless, loss of vision lasting for around 10 minutes each in the past 2 days. The episodes were followed by vomiting and gradual recovery of vision over the next few minutes. There was no associated headache, loss of postural tone, impairment of consciousness, tonic-clonic activity or focal deficits. There was no history of fever, head trauma, recurrent headaches, vertigo, dizziness or similar episodes in the past. There was a family history of epilepsy and intellectual disability in the paternal cousin. Detailed neurological and other system examination was unremarkable. Fundus examination showed normal disc and macula. A clinical diagnosis of amaurosis fugax was considered and the underlying etiologies suspected were transient ischemic attack and occipital epilepsy. Electroencephalogram showed persistent, arrhythmic, focal delta slowing over the right occipital area suggestive of an underlying structural pathology (Figure, Supplemental Digital Content, https://links.lww.com/INF/B780). Magnetic resonance imaging of the brain revealed right occipital ring-enhancing lesion with peri-lesional edema consistent with NCC (Fig. 1). Based on the clinico-radiological scenario, a presumptive diagnosis of NCC with symptomatic occipital epilepsy was considered and the child was started on antiepileptics (phenytoin 5 mg/kg/d) and oral prednisolone (2 mg/kg/d) followed by albendazole 15 mg/kg/d for 1 week. There was no recurrence of symptoms and the lesion disappeared after 6 months in repeat neuroimaging.FIGURE 1: Magnetic resonance imaging of the brain T2-weighted axial section showing right occipital neurocysticercosis with scolex (arrow) and peri-lesional edema (arrowhead).Vision loss in NCC can be multifactorial such as secondary optic atrophy due to hydrocephalus and papilloedema, optic nerve or chiasmal damage by inflammation and compression from adjacent cysts and retrochiasmal lesions including cortical blindness due to vasculitic cerebral infarction.1 The episode of transient blindness, however, reflects a transient dysfunction of visual cortex due to the cysticercal granuloma that triggered an occipital seizure with spread of seizure activity to both hemispheres, resulting in transient, bilateral blindness. This is termed ictal amaurosis and is a known manifestation of occipital lobe seizures. The cause of the occipital seizure may be a mass lesion (tumor, abscess, chronic granulomatous lesion, intracranial parasites, arteriovenous malformation) or idiopathic. Close clinical mimics are transient ischemic attacks due to thrombo-embolic phenomenon and idiopathic occipital epilepsy in children. Sometimes, the association of visual auras misleads the clinician to the possibility of migraine with aura till a neuroimaging reveals the cysticercal occipital granuloma.2 Transient cortical blindness in a 4-year-old boy with underlying NCC has been described.3 Being a treatable and preventable entity, it seems prudent to consider NCC in children from endemic regions who present with sudden onset neurological or cognitive disorders including unusual clinical manifestations such as amaurosis fugax. Additionally, neuroimaging is recommended in suspected cases of occipital epilepsies to rule out structural lesions such as NCC. Pratibha Singhi, MD, Arushi Gahlot Saini, MD Naveen Sankhyan, MD, DM Pediatric Neurology and Neurodevelopment Department of Pediatrics Postgraduate Institute of Medical Education and Research Chandigarh, India.

Neurocognitive evaluation in children with occipital lobe epilepsy

PurposeThis study aimed to explore cognitive functions in patients with childhood epilepsy with occipital paroxysms (CEOP) and to compare the performance of these patients with that of patients with symptomatic occipital epilepsy (SOE) and healthy control subjects. MethodTwenty-eight patients with epilepsy (17 CEOP, 11 SOE) were enrolled. The control group had similar demographical characteristics. Cognitive functions evaluated with Wechsler Intelligence Scale for Children-revised edition (WISC-R), The Visual Aural Digit Span (VADS) and Bender Visual Motor Gestalt Test (BVMG). ResultsThe WISC-R showed lower performance IQ with WISC-R in patients with occipital epilepsy than in healthy controls. The VADS test only showed lower scores in children with symptomatic occipital epilepsy. Mean BVMG test scores were significantly abnormal in both subgroups of childhood epilepsy with occipital paroxysms (early-onset CEOP/late-onset CEOP) and the group with SOE. ConclusionPatients with CEOP, especially the late-onset form, have significant problems in the domains of visuomotor coordination, memory and attention. The academic performance of these patients should be monitored carefully in follow-up and appropriate educational support should be given as necessary.

Structural correlates of fixation-off sensitivity: Evidences from a case of symptomatic occipital epilepsy with bilateral occipital gliosis

The fixation-off sensitivity (FOS), an epileptic phenomenon induced by elimination of central vision and fixation, is rarely seen in symptomatic occipital lobe epilepsy. The cerebral mechanisms and the structural correlate underlying FOS remain unclear. We describe a 19-year-old male with persistent left sided FOS following perinatal insult. MRI revealed asymmetric changes with more gliosis and ulegyria over the left posterior occipital cortex corresponding to the topographic representation of the macula. We suggest that the extensive denervation of the area representing macula along with the presence of hyperexitable ulegyric cortex is responsible for the phenomenon of FOS.

Episodic vomiting and headache in children: consider occipital epilepsy

Children with occipital seizures often have ictal autonomic symptoms such as pallor and vomiting and lack motor manifestations. This has lead to misdiagnosis of occipital seizures in children. The following case report highlights the clinical features of a child with occipital epilepsy misdiagnosed as having migraine. The aetiology of symptomatic occipital epilepsy will be discussed.

Idiopathic Childhood Occipital Epilepsy of Gastaut: A Review and Differentiation From Migraine and Other Epilepsies

The purpose of this review is to provide guidance for appropriate diagnosis and management of idiopathic childhood occipital epilepsy of Gastaut. The typical clinical features are visual seizures that typically consist of brief elementary visual hallucinations, which are mainly multicolored and circular. Ictal blindness and deviation of the eyes are also common symptoms. The seizures are usually frequent and diurnal. The electroencephalography is the only investigation with abnormal results, showing occipital spikes and often occipital paroxysms demonstrating fixation-off sensitivity. Brain magnetic resonance imaging is used to exclude symptomatic occipital epilepsy. Patients usually respond well to antiepileptic medication and about two-thirds remit by the age of 16 years. Idiopathic childhood occipital epilepsy of Gastaut is frequently misdiagnosed as migraine with visual aura, acephalgic, or basilar migraine. Differentiation from symptomatic occipital epilepsy, particularly when children are otherwise normal, can be difficult. Most children need prophylactic antiepileptic medication.

Symptomatic Occipital Epilepsy Misdiagnosed as Migraine

Two young patients with symptomatic occipital lobe epilepsy due to discrete lesions of cysticercosis were misdiagnosed and treated for 2 years as migraine with visual aura. The patients suffered from frequent visual seizures often followed by migraine-like headache. Seizures manifested with colored and mainly circular elementary visual hallucinations of up to 1 minute duration. Headache, often severe and of long duration, was frequently associated with nausea, photophobia, and phonophobia. Both patients became seizure-free with appropriate treatment of the underlying disease and epileptic seizures.

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.

Occipital epilepsies in children

Occipital lobe seizures, as defined by subjective symptoms and objective signs, can be recognized by clinical seizure characteristics in most cases. Visual symptoms such as hallucinations and amaurosis are the most common occipital lobe seizure symptoms. The patients must be classified in order to be able to define the prognosis. In this study, we classified patients with occipital epilepsy as childhood epilepsy with occipital paroxysms (19 patients), idiopathic photosensitive occipital epilepsy (10 patients) and symptomatic occipital epilepsy (25 patients). They were evaluated according to clinical, electrographic and neuroimaging characteristics.

Clinical correlations of electroencephalographic occipital epileptiform paroxysms in children

A longitudinal prospective approach was used to investigate clinical correlations of interictal occipital paroxysms with or without fixation-off sensitivity (FOS). Occipital paroxysms were recorded in the electroencephalograms (EEGs) of 76 children with heterogeneous clinical conditions including seizures in 39 patients . Occipital paroxysms with FOS (42 patients ) were only fractionally more frequent than non-FOS (34 patients ) and were not specific of any clinical condition. Although present and FOS-related in all 11 children with benign childhood epilepsies with occipital paroxysms (CEOP), they were also frequently encountered in symptomatic occipital epilepsy . The differentiation of CEOP from other syndromes established on clinical grounds could also be aided by the analysis of background EEG activity that was frequently significantly more abnormal in symptomatic than CEOP. Clinical characteristics and ictal seizure semiology as well as follow-up clearly distinguish two type of idiopathic CEOP syndromes: (1) early onset type or Panayiotopoulos syndrome characterized by excellent prognosis and rare, prolonged nocturnal seizures with tonic deviations of the eyes and vomiting, and (2) late onset or Gastaut type showing a common ictal visual symptomatology, co-occurrence of migraine, diurnal complex partial seizures and less favourable EEG-clinical prognosis.

Visual phenomena and headache in occipital epilepsy: a review, a systematic study and differentiation from migraine

ABSTRACT This is a systematic‐prospective study of occipital seizures with elementary visual hallucinations in 18 patients with symptomatic occipital epilepsy. Qualitative and chronological analysis showed that visual seizures usually lasted for seconds to 1‐3 minutes. Three patients also had longer visual seizures of 20‐150 minutes. Elementary visual hallucinations mainly consisted of coloured and small circular patterns flashing or multiplying in a temporal hemifield. Flashing lights or non‐circular patterns were rare. Three patients experienced achromatic flickering lights. None of the patients had the over 4 minute, linear, zigzag, and achromatic or black and white patterns characteristic of migraine visual aura. Blurring of vision could precede visual hallucinations. Visual seizures were usually frequent, often occurring in multiple clusters daily or weekly. They usually occurred alone but they often advanced to other occipital and extra‐occipital ictal symptoms. In 7 patients they progressed to temporal lobe seizure manifestations, and in 6 to motor partial seizures or ipsilateral hemiconvulsions. All but 2 had secondary generalised tonic clonic convulsions. Ictal blindness ab initio occurred in 2 and ictal, mainly orbital headache in another 2 patients. One patient had ictal vomiting as an occasional symptom. Postictal headache, often severe and indistinguishable from migraine, occurred in two thirds of the patients, even after brief visual seizures without convulsions. Despite relevant structural lesions in brain imaging, 10 patients had a normal mental and neurological state. In 8 patients, EEG was also normal or nonspecific. Misdiagnosis of visual seizures as visual aura of migraine was common and 3 patients were misdiagnosed as suffering from migraine.

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.