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In addition to visual field defects, occipital lobe injury can also cause fundus changes, such as retinal nerve fiber layer atrophy, ganglion cell complex atrophy and even optic nerve atrophy, and these fundus changes have a good correlation with the visual field defect site. It is considered to be caused by transneuronal retrograde degeneration (TRD) of retinal ganglion cells secondary to occipital lobe injury. These changes can be detected by means of optical coherence tomography, fundus examination, magnetic resonance imaging, etc. Among them, optical coherence tomography is more sensitive than other examinations. Here, the anatomical basis of TRD, case reports, pathogenesis, auxiliary examination, treatment and prognosis of TRD secondary to occipital lobe injury are reviewd.
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Objective:To investigate the clinical and electroencephalographic characteristics of photosensitive occipital lobe epilepsy (POLE) in children.Methods:The clinical data, electroencephalogram (EEG), treatment and prognosis of 22 children with POLE in the Department of Pediatrics, Peking University First Hospital from January 2006 to December 2019 were retrospectively analyzed.Results:Among the 22 patients, 12 cases were female and 10 cases were male.There were 3 cases combined with mild mental retardation.Classified by seizure symptoms, only 3 patients complained of subjective symptoms of visual aura, and the common symptoms were eye movement in 11 patients, headache in 3 patients, vomiting in 6 patients and dizziness in 3 patients.All patients had focal seizures during the course of disease.Twenty patients had secondary bilateral tonic-clonic seizures, and 5 patients also had generalized myoclonic seizures.Interictal epileptiform discharges were monitored in EEG of all children, including pure focal discharges in 6 patients, pure generalized discharges in 10 patients, and coexistence of generalized and focal discharges in 6 patients.Photoparoxysmal responses were induced in 19 patients, including pure focal discharges in 4 patients, pure generalized discharges in 6 patients, and coexisting focal and generalized discharges in 9 patients.Photoconvulsive responses were induced in 16 patients, including focal seizures with occipital lobe onset or focal secondary to bilateral tonic-clonic seizures in 15 patients, and myoclonic seizures in 1 patient.Eighteen patients were treated with anti-seizure medications (ASMs) and followed up.The top 3 commonly used drugs were Valproic acid (12 patients), Levetiracetam (8 patients), and Lamotrigine (4 patients), and 13 cases had controlled seizures.Conclusions:The visual aura of POLE is not obvious, and the relationship between epilepticseizures and light stimuli in daily life should be actively inquired to avoid misdiagnosis or underdiagnosis of the syndrome.The EEG of POLE often visualizes the coexistence of focal and generalized discharges, which may be accompanied by generalized seizures.The coexistence phenomenon should be considered when ASMs are medicated during treatment, and odium channel blockers should be selected carefully.
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Major depressive disorder (MDD) is a highly heterogeneous mental disorder, and its complex etiology and unclear mechanism are great obstacles to the diagnosis and treatment of the disease. Studies have shown that abnormal functions of the visual cortex have been reported in MDD patients, and the actions of several antidepressants coincide with improvements in the structure and synaptic functions of the visual cortex. In this review, we critically evaluate current evidence showing the involvement of the malfunctioning visual cortex in the pathophysiology and therapeutic process of depression. In addition, we discuss the molecular mechanisms of visual cortex dysfunction that may underlie the pathogenesis of MDD. Although the precise roles of visual cortex abnormalities in MDD remain uncertain, this undervalued brain region may become a novel area for the treatment of depressed patients.
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Humans , Depressive Disorder, Major/pathology , Brain/pathology , Antidepressive Agents/therapeutic use , Visual Cortex/pathologyABSTRACT
Major depressive disorder (MDD) is a highly heterogeneous mental disorder, and its complex etiology and unclear mechanism are great obstacles to the diagnosis and treatment of the disease. Studies have shown that abnormal functions of the visual cortex have been reported in MDD patients, and the actions of several antidepressants coincide with improvements in the structure and synaptic functions of the visual cortex. In this review, we critically evaluate current evidence showing the involvement of the malfunctioning visual cortex in the pathophysiology and therapeutic process of depression. In addition, we discuss the molecular mechanisms of visual cortex dysfunction that may underlie the pathogenesis of MDD. Although the precise roles of visual cortex abnormalities in MDD remain uncertain, this undervalued brain region may become a novel area for the treatment of depressed patients.
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Objective:To study the case of mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) which mimic migraine attacks with visual aura, to analyze the clinical features, and to recognize the nature of headache.Methods:The clinical features, image data and video electroencephalogram (EEG) of a suspected patient with MELAS were analyzed. Genomic DNA of mitochondria was extracted from blood and the next generation sequencing was performed to explore the mutation of genes about MELAS.Results:The patient was adolescent-onset, and presented with migraine-like attacks with visual aura, epileptic seizures, stroke-like episodes and hyperlactemia. Brain images suggested basal ganglia calcification, reversible left occipital cortex infarction and abnormal lactic acid peaks in both occipital cortex. Video EEG suggested abnormal adolescent EEG. Mitochondrial DNA sequencing showed that MT-TL1 gene had m. 3243A>G pathogenic mutation.Conclusions:There are a variety of clinical manifestations in MELAS, and migraine-like attacks with visual aura as initial symptoms may be manifestations of occipital lobe epilepsy. Clinicians should avoid confusing the diagnosis of migraine with visual aura, occipital epilepsy and MELAS, in order to make rational clinical decisions.
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Objective: To measure the occipital lobe volume in different genders of healthy Han Chinese adults with MRI. Methods: A total of 200 volunteers were selected from the healthy adult brain database of Han nationality in China. Whole-brain images were obtained using 3D magnetization prepared rapid acquisition gradient echo T1W sequence. The volume of left and right occipital lobes and whole brain volume were measured with manually sketching ROIs. Then the measured data were standardized, and the volume of left and right lateral occipital lobe were compared between different genders, the relation of the occipital lobe volume and age was analyzed, and the influence of gender and age to occipital lobe volume was analyzed. Results: The occipital lobe volume of normal adult was (105.37±10.41) cm3, which was (105.44±9.20) cm3 after standardization. Before standardization, the volume of occipital lobe in male adults ([111.34±9.15] cm3) was statistically different from that in females ([99.38±7.85]cm3), while after standardization, the volume of occipital lobe in male adults ([111.39±7.31]cm3) was also statistically different from that in females ([99.48±6.72]cm3,t=9.91, 12.01, both P0.05). Before and after standardization, no obvious correlation of occipital lobe volume with age in males or in females was observed (r=-0.01, 0.18, P=0.90, 0.08; r=0.05, 0.01,P=0.64, 0.92). There was no interaction between genders nor age on occipital lobe volume. Conclusion: The occipital lobe volume of healthy male adults is larger than that of females, and the volume of bilateral occipital lobe is basically the same in different genders. The occipital lobe volume is less likely to atrophy with age.
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Objective@#To investigate the clinical features of childhood epilepsy with occipital paroxysms.@*Methods@#The clinical data of 33 children admitted to our hospital from 2015 to 2019 were retrospectively analyzed.@*Results@#The children were divided into three groups: idiopathic group (n=20), structural group (n=10) and genetic group (n=3). Among the structural etiology group, there were 1 case of megagyrus malformation, 1 case of focal cortical dysplasia type Ⅱ (FCDⅡ), 1 case of gestational age infant with enlarged ventricle, and 7 cases of perinatal ischemic-hypoxic encephalopathy (HIE). In the genetic group, there were 1 case of PCDH19 gene mutation, 1 case of cyclin-dependent kinase like 5 (CDKL5) deficiency disorder and 1 case of Wolf-Hirschhorn syndrome. All three groups had ocular motor symptoms and secondary motor symptoms. Compared with the structural group, patients of the idiopathic group had more autonomic symptoms, less visual symptoms, longer ictal duration, less episodes, less abnormal background rhythm, and more epileptic discharges in the frontal lobe or Rolandic area. The genetic group had frequent seizures and the CDKL5 deficiency disorder patient had slowed background and spasms. Compared with the other two groups, patients of the idiopathic group had fewer MRI abnormalities, better seizure control effect, and better prognosis.@*Conclusions@#There are many causes of childhood epilepsy with occipital paroxysms. The idiopathic group accounts for a large proportion. The visual symptoms and autonomic symptoms are different between groups. Background abnormalities are detected more often in the structural group and the genetic group, which is also helpful for differential diagnosis. The treatment options and prognosis of different groups vary greatly. The overall therapeutic effect and prognosis of the idiopathic group are better than those of the structural group and the genetic group.
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Objective To investigate the clinical features of childhood epilepsy with occipital paroxysms.Methods The clinical data of 33 children admitted to our hospital from 2015 to 2019 were retrospectively analyzed.Results The children were divided into three groups:idiopathic group (n =20),structural group (n =10) and genetic group (n =3).Among the structural etiology group,there were 1 case of megagyrus malformation,1 case of focal cortical dysplasia type Ⅱ (FCD Ⅱ),1 case of gestational age infant with enlarged ventricle,and 7 cases of perinatal ischemic-hypoxic encephalopathy (HIE).In the genetic group,there were 1 case of PCDH19 gene mutation,1 case of cyclin-dependent kinase like 5 (CDKL5) deficiency disorder and 1 case of Wolf-Hirschhorn syndrome.All three groups had ocular motor symptoms and secondary motor symptoms.Compared with the structural group,patients of the idiopathic group had more autonomic symptoms,less visual symptoms,longer ictal duration,less episodes,less abnormal background rhythm,and more epileptic discharges in the frontallobe or Rolandic area.The genetic group had frequent seizures and the CDKL5 deficiency disorder patient had slowed background and spasms.Compared with the other two groups,patients of the idiopathic group had fewer MRI abnormalities,better seizure control effect,and better prognosis.Conclusions There are many causes of childhood epilepsy with occipital paroxysms.The idiopathic group accounts for a large proportion.The visual symptoms and autonomic symptoms are different between groups.Background abnormalities are detected more often in the structural group and the genetic group,which is also helpful for differential diagnosis.The treatment options and prognosis of different groups vary greatly.The overall therapeutic effect and prognosis of the idiopathic group are better than those of the structural group and the genetic group.
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Objective To investigate the clinical pathologic features of a distinct variant of focal cortical dysplasia (FCD) characterized by neuronal loss of layer four.Methods Between 2005 and 2017,approximately 3 000 surgeries were performed for the treatment of intractable epilepsy at Xuanwu Hospital,Capital Medical University and Yuquan Hospital,Tsinghua University.Retrospective analysis of clinic-pathological data of patients with epilepsy surgery was made and histological manifestations of neuronal loss of cortical layer four were included in this study.Results In this cohort,25 patients (22 males and three females) were identified with early onset pharmaco-resistant epilepsy and regionally circumscribed neuronal loss of cortical layer four in surgical specimens from the occipital lobe.Histologically,except for neuronal loss in cortical layer four in all cases,glial scar lesions were found in some patients.Thus the histology of those cases can be subdivided into two groups:group A (13 cases):neuronal loss of cortical layer four without glial scar lesions;and group B (12 cases):neuronal loss of cortical layer four with glial scar lesions.Due to the prominent horizontal disorganization of cortical layering and lack of any other microscopically visible principle lesion,group A should be classified hitherto as FCD International League Against Epilepsy (ILAE) type Ⅰ b,however,group B with scar lesions and cortical dysplasia around the main leision,should be classified as FCD ILAE type Ⅲd.This retrospective analysis of clinical histories revealed a perinatal distress in 20 patients (80％),suggesting an acquired pathomechanism.Magnetic resonance imaging revealed abnormal signals in the occipital lobe in all patients,and signal changes suggestive of encephalomalacia were found in 18 patients.Surgical treatment achieved favorable seizure control (Engel class Ⅰ and Ⅱ) in 18 patients (75％ among 24 available follow up).Comparion of the two groups with age at epilepsy onset (group A:5.00±2.76,group B:5.01±3.78),the proportion of perinatal distress (group A:11/13,group B:9/12) and the follow-up results (favorable seizure control of the two groups was 9/13,9/11 respectively) showed that there was no statistically significant difference between the two groups.Conculsion Neuronal loss of cortical layer four in the occipital lobe should be classified as a distinct variant of FCD ILAE type Ⅲd.
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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.
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Objectives To investigate the occipital cortex metabolite alterations in repetitive and severe neonatal hypoglycemia rats treated with sodium pyruvate and to reveal the protective role of sodium pyruvate using high resolution 1H nuclear magnetic resonance spectroscopy.Methods Thirty-six 2-dayold Sprague-Dawley rats were randomly divided into hypoglycemia group and pyruvate group with 18 rats in each group.Rats in both groups received intraperitoneal injections of insulin (40 U/kg body weight) at 2,4 and 6 days of age to induce severe hypoglycemia (blood glucose value ≤ 1.4 mmol/L).In the hypoglycemia group,2.5 hours after insulin injection,intraperitoneal injection of 50％ glucose (2 ml/kg) was administered to terminate hypoglycemia,while in the pyruvate group,50％ glucose (2 ml/kg) and sodium pyruvate solution 2.5 ml/kg (500 mg/kg) were injected.Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay was used to observe the status of injured neurons in six neonatal rats,and metabolite changes in occipital cortex of the other 12 rats were detected by 1H nuclear magnetic resonance spectroscopy.The difference between the two groups was compared by independent-samples t test.Results Neonatal rats of both groups reached severe hypoglycemia level 2.5 hours after insulin injection.Compared with hypoglycemia group,pyruvate group had fewer injured neurons (45±5 vs 113 ± 12,t=0.782,P=0.013) and lower injured index in the occipital cortex (0.15 ± 0.03 vs 0.36 ± 0.06,t=l.143,P=0.020).Pyruvate group showed significant decreases in the concentration of taurine [(13.31 ± 2.06) vs (18.44 ± 3.86) mol/kg,t=8.231],glutamine[(1.50 ± 0.24) vs (2.02 ± 0.40) mol/kg,t=3.137],glutamate[(7.04 ± 0.95) vs (9.40 ± 1.73) mol/kg,t=6.449],aspartate[(1.51 ± 0.28) vs (2.15 ± 0.58) mol/kg,t=2.561] and creatine [(6.37±0.99) vs (8.46± 1.77) mol/kg,t =4.226] in the occipital cortex (all P'＜0.017).Conclusions Simultaneous use of glucose and sodium pyruvate to terminate hypoglycemia in repetitive and severe neonatal hypoglycemia rats can effectively alleviate severe hypoglycemia-induced occipital lobe damage via regulating excitatory amino acid neurotransmitters,energy metabolism and other metabolic pathways.
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PURPOSE: To report brain metastasis of hepatocellular carcinoma presenting as homonymous hemianopia. CASE SUMMARY: A 51-year-old female with a history of hepatectomy and diagnosis of hepatocellular carcinoma (HCC) 19 months earlier was referred to our neuro-ophthalmology clinic for evaluation due to headache and decreased visual acuity over the past several months. Best visual acuity was 20/20, and the results of all other aspects of our examination were normal except Humphrey automatic perimetry, which showed complete left homonymous hemianopia. Brain magnetic resonance imaging showed a large mass in the right occipital lobe. Craniotomy and removal of tumor were performed. HCC was confirmed by histopathologic examination. CONCLUSIONS: Metastasis of hepatocellular carcinoma to the occipital lobe is extremely rare but can present as homonymous hemianopia. Therefore, clinicians should be aware of this when examining a patient with a history of HCC.
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Female , Humans , Middle Aged , Brain , Brain Neoplasms , Carcinoma, Hepatocellular , Craniotomy , Diagnosis , Headache , Hemianopsia , Hepatectomy , Magnetic Resonance Imaging , Neoplasm Metastasis , Occipital Lobe , Visual Acuity , Visual Field TestsABSTRACT
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.
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Adult , Female , Humans , Brain , Electroencephalography , Epilepsies, Partial , Epilepsy, Generalized , Magnetic Resonance Imaging , Nerve Fibers , Neuroimaging , Occipital Lobe , Retinal Ganglion Cells , Retinaldehyde , Seizures , Tomography, Optical Coherence , Visual Acuity , Visual Field Tests , Visual Fields , Visual PathwaysABSTRACT
No abstract available.
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Epilepsies, Partial , Headache , Hemianopsia , Migraine Disorders , Occipital LobeABSTRACT
Purpose Two kinds of forward conditional reasoning including modus ponens (MP) and denial of the antecedent (DA) are the most common deductive reasoning in daily life. The present study aimed to explore the difference between the two neural machanisms. Materials and Methods Three kinds of tasks including MP, DA, and baseline were administrated to 14 undergraduates [7 males and 7 females, mean age (23.4±1.3) years] by using functional magnetic resonance imaging (fMRI) technique. fMRI data was analyzed. Results The reaction times were significantly slower for MP and DA than that of BS (P<0.001), while the effect was not significant for accuracy. In contrast to baseline, both MP and DA tasks activated the left inferior frontal cortex (BA 9), inferior parietal lobule (BA 40), and postcentral gyrus. Bilateral caudate significant activation was found in MP task when compared with DA, whereas the frontal, parietal, occipital lobe and anterior cingulate cortex were acivated more in the DA than in MP task. Conclusion Both forward conditional reasoning of MP and DA commonly activate the left frontoparietal cortex, while significant dissociations can be seen in the regions of caudate and bilateral frontal, parietal and occipital. These results firstly demonstrates the different neural mechanism underlying the two forward conditional reasoning, which might help to further uncover the brain mechanism of conditional reasoning.
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Introdução: A anatomia da face súpero-lateral do lobo occipital é tão complexa e variável que a sua descrição precisa não é encontrada nos livros clássicos de anatomia. Os sulcos e giros occipitais da convexidade cerebral encontram-se descritos com nomenclaturas diferentes de acordo com os diversos autores. O objetivo deste estudo foi investigar e descrever a anatomia da face súpero-lateral lobo occipital e esclarecer a sua nomenclatura. Métodos: As configurações anatômicas dos sulcos e giros na face súpero-lateral do lobo occipital de 20 hemisférios cerebrais foram examinados a fim de identificar os padrões mais característicos e consistentes. Resultados: Os sulcos occipitais mais característicos e consistentes identificados neste estudo foram o sulco intraoccipital, o sulco occipital transverso e o sulco occipital lateral. A morfologia da junção do sulco occipital transverso com o sulco intraoccipital foi identificada como sendo o aspecto mais importante para definir o padrão de giros cerebrais da face súperolateral do lobo occipital. Conclusões: O conhecimento das principais características dos sulcos e giros occipitais permite o reconhecimento de uma configuração básica do lobo occipital e a identificação de suas principais variações anatômicas.
Background: The anatomy of the occipital lobe convexity is so intricate and variable that its precise description is not found in the classic anatomy textbooks, and the occipital sulci and gyri are described with different nomenclatures according to different authors. The aim of this study was to investigate and describe the anatomy of the occipital lobe convexity and clarify its nomenclature. Methods: The configurations of sulci and gyri on the lateral surface of the occipital lobe of 20 cerebral hemispheres were examined in order to identify the most characteristic and consistent patterns. Results: The most characteristic and consistent occipital sulci identified in this study were the intraoccipital, transverse occipital, and lateral occipital sulci. The morphology of the transverse occipital sulcus and the intraoccipital sulcus connection was identified as the most important aspect to define the gyral pattern of the occipital lobe convexity. Conclusions: Knowledge of the main features of the occipital sulci and gyri permits the recognition of a basic configuration of the occipital lobe and the identification of its sulcal and gyral variations.
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Humans , Male , Female , Anatomy , Cadaver , Neuroanatomy , Occipital Lobe , Terminology as TopicABSTRACT
OBJECTIVES: This study investigated the clinical characteristics and functional magnetic resonance imaging (fMRI) findings of firefighters suffering from partial posttraumatic stress disorder (partial PTSD). They were treated by eye movement desensitization and reprocessing (EMDR) and the treatment effect was evaluated. METHODS: A total of 116 firefighters were screened and 15 of them were diagnosed as partial PTSD. 1) We compared sociodemographic and psychological characteristics between the firefighter partial PTSD group and the firefighter control group. 2) Subjects in the firefighter partial PTSD group (n=10), firefighter control group (n=8), and general control group (n=12) underwent fMRI with traumatic, negative, positive, and neutral picture stimuli. We compared clinical characteristics and fMRI findings among these three groups. 3) Seven firefighters in the partial PTSD group were treated by EMDR and the treatment effect was evaluated according to psychological scales. RESULTS: In fMRI analysis, there was a left middle temporal/occipital activation in the order of the general control group, firefighter control group, than the firefighter partial PTSD group for the Traumatic-Baseline contrast. For the Negative-Baseline contrast, there was an increased left middle temporal/occipital activation in the general control group versus decreased activation in the firefighter control group and the firefighter partial PTSD group. All firefighters in the partial PTSD group treated by EMDR showed significant improvement of Clinician-Administered PTSD Scale scores. CONCLUSION: These results show high incidence rate of partial PTSD in firefighters. In addition, partial PTSD firefighters exhibited distinct clinical characteristics and fMRI findings and showed significant improvement by EMDR treatment.
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Humans , Eye Movement Desensitization Reprocessing , Eye Movements , Firefighters , Incidence , Magnetic Resonance Imaging , Occipital Lobe , Stress Disorders, Post-Traumatic , Temporal Lobe , Weights and MeasuresABSTRACT
Introduction: Anton’s syndrome is a condition where the patient is unaware of being blind and denies the problem even when it is pointed out to him. On the contrary, in cortical blindness patient is aware of his blindness and does not deny it. In both, bilateral lesions of the occipital lobes are seen. Case presentation: We present two cases of cortical blindness, Case 1 being consistent with diagnosis of Anton’s syndrome where patient denied of her blindness. Both cases revealed bilateral occipital lobe infarcts. Conclusions: Cerebrovascular disease is the most common cause of cortical blindness. These occur as a result of successive infarctions as seen in Case 1 or from a single embolic or thrombotic occlusion as seen in Case 2. First case is Anton’s syndrome with patient denying blindness, whereas second case is cortical blindness. It is due to involvement of other cortical centers in Anton’s syndrome that patient denies blindness.
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Objective To explore the activation on occipital lobe in children with and without abacus mental calculation training when they engaged in different calculation tasks with functional magnetic resonance imaging (fMRI).Then approach the laterality of occipital lobe in abacus mental calculation.Methods fMRI was performed in children trained with( trained group)and without( untrained group) abacus mental calculation( seventeen in each group) when they engaged in addition,subtraction,multiplication,division,and number-object control judging tasks.The data processing and statistical analysis of original image were performed on SPM 2.0 ( statistical parametric mapping 2.0) and the related-brain functional areas were obtained.The laterality index (LI) was used to assess the laterality of occipital lobe.Results The performance of the trained group with better correctness and shorter reaction time was much better than that of the untrained group (P＜0.01).The laterality degree of occipital lobe in the trained group (-0.15,0.22,0.24,-0.06 ) was lower than that of the untrained group (0.35,0.75,0.75,0.29).Conclusion Abacus mental calculation can obviously enhance the capacity of mental calculation.The laterality degree of occipital lobe in the trained group is lower than that of untrained group.It is conducive to the balanced development of bilateral cerebral hemisphere.
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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.