Localization diagnosis and surgical treatment of intractable occipital epilepsy / 局解手术学杂志

Objective To explore the preoperative localization diagnosis and surgical techniques of intractable occipital lobe epilepsy.Methods Retrospectively studied 37 patients diagnosed as occipital lobe epilepsy and underwent focal occipital resections for epilepsy.The semiology,scalp electroencephalography,MRI,fluorodeoxyglucose-positron emission tomography(FDG-PET),and intracranial EEG monitoring were used to localize the epileptogenic zones.The long-term seizure outcomes were assessed according to the Engel classification scheme.Results Visual symptoms were present in 25 patients preoperatively in this series.MRI displayed occipital lobe lesions in 15 patients,and FDG-PET revealed hypometabolism in or adjacent to epileptogenic zones.And 30 patients' epileptogenic zones and functional areas were defined by intracranial EEG monitoring.Visual field deficits were present in 35.3% of patients preoperatively,and 61% had new or aggravated visual field deficits after surgery.After a mean follow-up of 41 months,81.1% of the patients were seizure free or rarely had seizures.Conclusion The curative effect of the surgery on the medically intractable occipital lobe epilepsy is good.Intracranial EEG monitoring with electrodes extensively covering the occipital lobe and adjacent areas can be useful to demarcate the epileptogenic zones and the visural cortex,and it may prevent aggravation of the visual field deficits as much as possible.

A Case Report of Occipital Lobe Epilepsy and Related Optical Coherence Tomography Findings

PURPOSE: In the present case report, visual pathway damage confirmed by retinal ganglion cell layer (GCL) damage on optical coherence tomography (OCT) in occipital lobe epilepsy was described. CASE SUMMARY: A 25-year-old female with idiopathic generalized epilepsy developed visual blurring followed by a generalized seizure. On brain magnetic resonance imaging (MRI), very subtle changes of the cortex in the left parietooccipital lobe were observed. Two days after the attack, even after the disappearance of epileptiform wave on electroencephalogram (EEG), visual acuity in both eyes was 0.5 and a perimetry revealed nearly complete visual defect in both eyes. OCT showed severe thinning of GCL and mild thinning of retinal nerve fiber layer (RNFL). No additional seizure attack occurred thereafter. One month after the attack, her visual acuity was recovered to 1.0 in both eyes and her left visual hemifield defect was recovered. However, even 6 months after the attack, her right visual hemifield defect and GCL damage persisted in both eyes. CONCLUSIONS: We reported a case in which the visual pathway damage caused by occipital lobe epilepsy was identified using OCT, despite very subtle changes in brain imaging. This case indicated GCL thinning is an objective and prognostic index for the irreversible visual field defect in occipital lobe epilepsy.

Occipital Lobe Epilepsy with Hemicrania Epileptica

No abstract available.

Occipital Lobe Simple Partial Epilepsy Presenting as Visual Episodes Associated with Non-Ketotic Hyperglycemia / 대한간질학회지

Non-ketotic hyperglycemia (NKH) is recognized both as a direct cause of a precipitating factor of many types of epileptic seizure, including simple partial motor, complex partial as well as reflex motor seizure, choreoathetosis and ballismus. Its association with isolated visual alteration is less known. A 74-year-old diabetic woman with visual complaints manifested as flashing colorful lights (red, yellow and blue) in both visual field with progressive increase in frequency. Among the laboratory tests, NKH of 508mg/dL stood out. Slow waves from the right occipital region maximum at O2 associated with visual symptom were recorded in EEG. Brain MRI showed subcortical T2WI and FLAIR hypointensities in the right occipital lobe with scanty enhancement. Patient was treated with hydration and insulin and her symptoms disappeared after hyperglycemia was corrected. We stress that isolated visual episodes may be initial manifestation of occipital lobe simple partial seizure associated with NKH.

Concomitant Absence and Occipital Lobe Epilepsy in an Adolescent

The incidence of absence and occipital lobe epilepsy appearing in the same young individual is quite rare. A fourteen year-old girl has had two types of recurrent seizures: 1)simple partial seizure with secondary generalization probably originating in the left occipital lobe, and 2)absence seizure. Electroencephalogram demonstrated frequent spikes on the left occipital region with or without bilateral synchronization and generalized 3 Hz spike and wave complexes during hyperventilation procedure and photic stimulation.

Clinical Characteristics of Occipital Lobe Epilepsy in Children / 대한간질학회지

PURPOSE: To evaluate the differential clinical & electroencephalographic characteristics between benign childhood epilepsy with occipital paroxysm (BCEOP) and symptomatic occipital lobe epilepsy (SOLE). METHODS: Nine patients of BCEOP and seven patients of SOLE diagnosed at the department of pediatrics and epilepsy center in Inje University Sang-gye Paik Hospital from March 1992 to June 1998, were studied for the determination of differential characteristics between the two groups. Clinical features, EEG characteristics, MRI findings, associated conditions, and prognosis were investigated and compared between these groups. RESULT: 1) Male : female ratio was 1 : 2 in BCEOP and 1 : 2.5 in SOLE. 2) Seizure onset age was older in SOLE as compared with BCEOP. 3) There was no significant difference in seizure types between two groups. 4) Visual aura could be elicited in 5 patients (55.6%) in BCEOP, and 3 patients (42.9%) in SOLE. 5) Ictus emeticus was only noted in 4 patients (44.4%) of BCEOP. 6) Migraine was associated only in 3 patients of BCEOP. 7) Background EEG abnormality was more frequently associated in SOLE than BCEOP. 8) Seizure control was inefficient only in 3 patients (42.9%) of SOLE, and all patients with BCEOP were successfully treated with antiepileptic drugs. CONCLUSION: SOLE showed higher seizure onset age, less frequent association of ictus emeticus and migraine, more frequent background EEG abnormalities and more medical intractability to antiepileptic drugs than BCEOP.

A Case of Status Epilepticus Amauroticus / 대한간질학회지

Ictal blindness is a deficient symptomatology of partial seizure arising from visual cortex and usually short lived. When the blindness is the initial semiology of seizures, epileptic discharge arising from the primary visual cortex is associated. Ictal blindness has been reported in many patients with occipital lobe epilepsy, but prolonged ictal blindness called status epilepticus amauroticus has been reported only in few patients. We report a 45-year-old woman who had suffered prolonged epileptic blindness. The epileptic blindness was accompanied with rapid eyelid blinking and upward turning of head and eyeballs. Motor seizure and mental changes were not occurred. Ictal EEG showed 11-13 Hz repetitive spikes on the right occipital area followed by propagation to ipsilateral temporal area and contralateral occipital area. On T2-weighted MRI, abnormal lesions with high signal intensity were noted within bilateral occipital areas. She had been improved dramatically by loading dose of intravenous phenytoin.

Clinical Manifestations and Prognostic Factors of Occipital Lobe Epilepsy in Children

PURPOSE: The objective of this study is to review the clinical manifestations and acknowledge the prognostic factors in occipital lobe seizure and benign childhood epilepsy with occipital paroxysm (BEOP). METHODS: We reviewed retrospectively 253 cases who showed occipital epileptiform activity on EEG at the Pediatric Neurology Clinic, Yonsei University Medical Center from January 1997 to June 1999, and selected 72 cases who had been followed-up for over 2 years. According to the occurrence of seizure for recent 2 years, they were classified into 2 groups : favorable and unfavorable groups. Clinical manifestations were reviewed and analyzed in each group with chi-square and student t-test. RESULTS: 1) Symptomatic group was 16 out of 72 cases (22%), and cryptogenic group was 56 cases (78%). Seventeen out of 72 cases (24%) had the clinical manifestation of BEOP. 2) Early-onset variant is 9 out of 17 cases (52%), late-onset was 8 cases (48%) in BEOP patients. 3) Prognostic factors influencing unfavorable prognosis were prematurity, LBW, perinatal asphyxia and postictal headache in occipital lobe seizure. 4) Prognostic factors in BEOP were determined by age of onset, existence of visual symptom, oculomotor symptom, automatism, autonomic symptom, postictal headache, and diurnal or nocturnal seizure. CONCLUSION: Occipital lobe seizure manifests various clinical symptoms with various prognosis. Seventeen out of 72 cases were determined as BEOP: 9 cases of early variant and 8 cases of late onset. We acknowledge the prognostic factors in epilepsy with occipital lobe seizure as well as BEOP.

Comparison of Diagnostic Performance between Interictal F-18-FDG PET and Ictal Tc-99m-HMPAO SPECT in Occipital Lobe Epilepsy / 대한핵의학회잡지

PURPOSE: Interictal F-18-fluorodeoxyglucose (FDG) PET and ictal Tc-99m-HMPAO SPECT are found to be useful in localizing epileptogenic zones in neocortical lateral temporal or frontal lobe epilepsy. We investigated whether interictal F-18-FDG PET or ictal Tc-99m-HMPAO SPECT was useful to find epileptogenic zones in occipital lobe epilepsy (OLE). MATERIALS AND METHODS: We reviewed patterns of hypometabolism in interictal F-18-FDG PET and of hyperperfusion in ictal Tc-99m-HMPAO SPECT in 17 OLE patients (mean age=27+/-6.8 year, M:F=10:7, injection time=30+/-17 sec). OLE was diagnosed based on invasive electroencephalography (EEG) study, surgery and post-surgical outcome (Engel class I in all for average 14 months). RESULTS: Epileptogenic zones were correctly localized in 9 (60%) out of 15 patients by interictal F-18-FDG PET. Epiletogenic hemispheres were correctly lateralized in 14 patients (93%). By ictal Tc-99m-HMPAO SPECT, epileptogenic hemispheres were correctly lateralized in 13 patients (76%), but localization was possible only in 3 patients (18%). Among patients who showed no abnormality with MR imaging and no correct localization with ictal Tc-99m-HMPAO SPECT, interictal F-18-FDG PET was helpful in 2 patients. CONCLUSION:: Ictal Tc-99m-HMPAO SPECT was helpful in lateralization but not in localization in OLE. Interictal F-18-FDG PET was helpful for localization of epileptogenic zones even in patients with ambiguous MR or ictal SPECT findings. Key KW: Occipital lobe epilepsy, Tc-99m-HMPAO, Ictal perfusion SPECT, F-18-FDG, PET, SPECT

Surgical Treatment of the Occipital Lobe Epilepsy

PURPOSE: Although occipital lobe epilepsy may be operable, localization of the epileptogenic zone can be difficult and there is a high risk of postoperative visual loss. METHODS: Thirteen patients with intractable occipital lobe epilepsy underwent resective surgery. Preoperatively, all underwent video-EEG monitoring using extracranial electrodes and MRI; Nine had PET scans; In ten, who were cortically stimulated with subdural grid electrodes, invasive recordings were made. Foramen ovale electrodes had been previously used in two, and bitemporal depth electrodes in one; Nitemporal and occipital electrodes had been used in one, and a unilateral temporal depth electrode in one. Nine underwent partial occipital resection, which had spared the nonepileptogenic primary visual cortex, and two underwent a total unilateral occipital lobectomy: A temporal lobectomy was performed in two. RESULTS: Twelve patients experienced visual aura prior to complex partial seizure, and five had quadrantanopsia. In no patient was noninvasive monitoring reliable in localizing the epileptogenic zone, and in eleven patients, this was localized by invasive recordings. Electrocortical stimulation with subdural grid electrodes evoked simple and complex visual phenomena in nine patients, reproduced the same auras in four, induced a typical seizure in two, and provided language mapping in five. Histopathologic findings revealed cortical dysplasia in five; Tuberous sclerosis was combined in one, hamartoma and ganglioglioma, each in two, and infarction and nonspecific change in the occipital lobe each in one, neuronal loss in the hippocampus and neuronal heterotopia in mesial temporal structures were reported in two patients who underwent temporal lobectomy. Ten were seizure-free during follow-up between six and 46(mean 22.3) months. Seizures recurred in two and were unchanged in one. Only two patients with preoperative quadrantanopsia developed homonymous hemianopsia. CONCLUSION: This study suggests that in the surgical treatment of the occipital lobe epilepsy, the use of intracranial EEG and functional mapping with subdural grid electrodes, can achieve a good outcome, including the preservation of vision.