Occipital encephalocele

The brain from an infant with a cystic occipital mass present at birth is examined in serial section. The occipital mass proved to be a rhombic roof ventriculocele. Within the posterior fossa, it was bound to an occipital lobe encephalocele which issued as a diverticulum of the left lateral ventricle through a microgyric cortical defect in the territory of the left posterior cerebral artery. The posterior medial aspects of both cerebral hemispheres were herniated downward into the widened tentorial gap. Craniolacunae were prominent on the inner aspect of the skull. The aqueduct and central canal of the spinal cord were widely dilated, although the lateral ventricles were collapsed. It is suggested that hydrocephalus secondary to obstruction to flow of CSF through the rhombic roof entrained a sequence of events giving rise to the rhombic roof ventriculocele and causing occlusion of the posterior cerebral artery and subsequent diverticulation of the lateral ventricle through an infarcted region of the posterior-medial hemisphere.     

Occipital encephalocele associated with a dermoid cyst.

The case of a neonate with a dermoid cyst originating within an occipital encephalocele is reported. The finding of the tumor was made during the routine repair of the meningoencephalocele. To our knowledge this is the first time that this association has been described.     

Occipital lobe epilepsy secondary to ulegyria

Objective To analyse clinical and therapeutic aspects of epilepsy secondary to ulegyria in adults. Patients Out of 1,020 consecutive patients studied at a tertiary care epilepsy centre, eight cases of ulegyria were identified. All patients had comprehensive clinical evaluation, neuropsychological testing, interictal EEG, and brain magnetic resonance imaging (MRI). In addition, five patients had video–EEG monitoring. Ulegyria was confirmed by histological analysis in two patients who had successful epilepsy surgery. Results All patients had a history of perinatal asphyxia. In four of them there was psychomotor developmental delay. Mean age at onset of seizures was 5.8 years (range first week to 21 years). Brain MRI demonstrated predominant involvement of occipito–parietal cortical and subcortical areas. This posterior distribution of lesions was also supported by the presence of auras with occipital and parietal semiology in six patients, and signs of visuospatial dysfunction in five. Four patients had medically refractory epilepsy and two of them had significant improvement with surgical treatment. Conclusions In this group of adult epileptic patients with ulegyria brain MRI, ictal semiology, and neurological examination are consistent with occipital lobe epilepsy. Most patients have severe epilepsy, but in some of them epilepsy can be controlled with antiepileptic drugs, while in others surgical treatment can be effective. Brain MRI criteria of ulegyria are well established, and in two cases it was possible to confirm their diagnosis with histological analysis.     

儿童期枕叶癫痫与随访

儿童期枕叶癫痫，一般概念是指儿童期良性特发性（原发性）癫痫，此类为罕见疾病。本组６例，不仅有上述类型，还有儿童期症状性（继发性）癫痫，６例均于发病后每年至少随访检查一次，症状性者其预后也较好。并对特发性枕叶癫痫与症状性枕叶癫痫及其随访结果与预后作了讨论     

Occipital ulegyria causing epilepsy and visual impairment: an easily overlooked epilepsy syndrome

Ulegyria refers to scarring of the cerebral cortex usually arising from perinatal ischaemia. The scarring has a specific configuration in which small atrophic circumvolutions at the bottom of a sulcus underlie an intact spared gyral apex. This disconnection of overlying cortex may allow an “epileptogenic” island of cortex to generate seizures. Ulegyria is often associated with epilepsy and developmental delay, however, the syndromic association of visual impairment with epilepsy due to occipital ulegyria may not be recognised as a specific entity. Here, we report a series of five patients with occipital ulegyria who presented with widely variable seizure semiology and an array of visual deficits. In some patients, the link between the epilepsy and the visual impairment was not appreciated until they attended an epilepsy clinic.     

被误诊为精神运动性癫痫发作的枕叶癫痫

目的枕叶癫痫是一种主要表现为视觉症状的癫痫发作。它的发作症状形式多样,头皮脑电图变化不明显,容易与精神运动性癫痫发作(PNES)以及枕叶外其他部位的癫痫发作相混淆。该文报道1例表现为反复出现视觉白光被误诊为PNES的枕叶癫痫。文章表明头皮脑电图对枕叶癫痫的诊断意义不大,特别是脑电图呈阴性时要注意与PNES相鉴别。而颅内脑电图、发作期SPECT、MRI等方法在枕叶癫痫的定位诊断中更有意义。     

Occipital lobe epilepsy with fear as leading ictal symptom

Ictal fear is a semiological feature which is commonly associated with mesial temporal lobe epilepsy. Here, we describe fear as a leading symptom in cryptogenic occipital lobe epilepsy. In a patient with negative MRI findings, intracranial EEG recordings documented a strict correlation between habitual ictal anxiety attacks and both spontaneous and stimulation-induced epileptic activity in a right occipital epileptogenic area with subsequent spreading to the symptomatogenic zone in the amygdala. Circumscribed occipital topectomy led to seizure freedom. Episodes of non-epileptic fear ceased shortly afterwards. This report provides insight into pathways of propagation of epileptic activity, illustrates different etiologies of pathologic fear and underlines the importance of ictal EEG recordings.     

Occipital encephalocele,lipomeningomyelocele, and Chiari I malformation: case report and review of the literature

CASE REPORT. We report a pediatric patient with encephalocele, lipomeningomyelocele, and Chiari I malformation. DISCUSSION. We also review the extant medical literature regarding associations between these three entities. We propose that the combination of these three pathologies, which is reported here for the first time, is not serendipitous but rather a low-frequency association. CONCLUSIONS. After a literature review, we speculate that encephalocele and lipomeningomyelocele most probably occur by mechanisms similar to those that produce encephalocele and meningomyelocele and that the tonsillar ectopia in our patient is due to an abnormally small posterior cranial fossa resulting from the lack of neural tissue within the cranium at critical times during development or has its genesis, as some encephaloceles may, in inappropriate paraxial mesoderm formation.     

枕叶癫痫外科治疗的特点与疗效(附13例报道)

目的 探讨枕叶癫痫外科治疗的特点与手术疗效.方法 回顾分析13例枕叶癫痫患者完整的临床资料,总结其发作症状学、影像学、EEG、神经病理学及手术治疗等方面的特征与手术疗效.结果 局灶性皮质发育不良为最常见病理表现(6例).术后2周时6例患者原有视觉障碍加重或新出现视觉障碍.术后随访2～5年,Engel's I级7例(53.8%),II级1例,III级2例,IV级3例.结论 定位明确的枕叶癫痫可以通过适当的手术治疗获得较满意疗效,但常常加重视觉功能障碍.     

Photic epilepsy]

Fourteen cases of patients with photoconvulsive response during intermitent luminous stimulation (eleven women and three men) are reviewed. The frequency of the photoconvulsive response was higher between 10 and 20 years of age (eleven cases). Most of the patients (twelve) presented some form of epilepsy and only two had psychomotor retardation without epilepsy. Comment is made on differences published by other authors and possible explanations of such differences are proposed.     

Occipital lobe epilepsy: clinical characteristics, surgical outcome, and role of diagnostic modalities

PURPOSE: To assess the role of various diagnostic modalities, to identify surgical prognostic factors and concordances with presurgical evaluations, and to characterize the clinical features of occipital lobe epilepsy (OLE), we studied 26 patients who were diagnosed as having OLE and underwent epilepsy surgery. METHODS: Diagnoses were established by standard presurgical evaluations, which included magnetic resonance imaging (MRI), fluorodeoxyglucose-positron emission tomography (FDG-PET), ictal single-photon emission computed tomography (SPECT), scalp video-EEG monitoring, and intracranial EEG monitoring. After epilepsy surgery, patients were followed up for >2 years. RESULTS: Sixteen (61.5%) of the 26 became seizure free after surgery, and another eight patients had a favorable outcome. Sixteen of the 26 patients experienced a type of visual aura (i.e., visual hallucination, visual illusion, blindness, or a field defect). Nine patients had both automotor seizures and secondary generalized tonic-clonic seizures at different times. Interictal EEG showed correctly localizing spikes in 10 of the 16 patients who became seizure free, and in three of the 10 non-seizure-free patients. MRI correctly localized the lesion in seven of these 16 seizure-free patients, and in three of the 10 non-seizure-free patients. FDG-PET correctly localized the lesion in eight of the 16 seizure-free patients, and in three of nine non-seizure-free patients. Ictal SPECT was performed in 19 patients and correctly localized the lesion in only three of 12 seizure-free patients, and in four of seven non-seizure-free patients. Ictal EEG correctly localized the lesion in 13 of the 16 seizure-free patients, and in five of the 10 non-seizure-free patients. No significant relation was found between the diagnostic accuracy of any modality and surgical outcome. The localizations of epileptogenic zones by these different diagnostic methods were complementary. The concordance of three or more modalities was significantly observed in seizure-free patients (p = 0.042). However, no definite relation was observed between the presence of lateralizing clinical seizure manifestation and surgical outcome (p = 0.108). CONCLUSIONS: Some specific auras indicated an occipital epilepsy onset. Various diagnostic methods can be useful to diagnose OLE, and a greater concordance between presurgical evaluation modalities indicates a better surgical outcome.     

Occipital hypometabolism demonstrated by positron emission tomography after temporal lobectomy for refractory epilepsy.

BACKGROUND: Epilepsy surgery involves well-planned discrete injury to the brain and may create visual deficits. This study seeks to evaluate the indirect effects of temporal lobectomy on brain metabolism by correlating visual field defects and glucose metabolism in the visual cortex of patients before and after undergoing epilepsy surgery. METHODS: A retrospective survey of 11 patients who had undergone temporal lobectomy for refractory epilepsy in a single institution from 1986 to 1989, and who had pre-lobectomy and post-lobectomy visual field examinations and F-18 2-fluorodeoxyglucose positron emission tomography (FDG-PET) as part of a standard comprehensive epilepsy surgery evaluation. The PET images were analyzed to provide a correlation with the visual field defects that developed after the temporal lobectomy. RESULTS: Occipital hypometabolism in the absence of structural lesions of the occipital lobe was noted in seven patients with contralateral visual field defects and in one of four patients without a visual field defect. FDG-PET studies in three patients repeated for as long as 20 months after lobectomy showed no significant change in the occipital hypometabolism pattern. CONCLUSIONS: Although the occipital cortex was not directly injured during temporal lobectomy, the resulting hypometabolism correlates with the clinical findings of visual field defects. The hypometabolism may be due to deafferentation after interruption of the optic pathways and appears to be persistent.