Alterations In Cerebral Function Research Articles

Hyperactivity of the medial thalamus in patients with photophobia-associated migraine.

To examine cerebral functional alterations associated with sensory processing in patients with migraine and constant photophobia. Migraine is a common headache disorder that presents with photophobia in many patients during attacks. Furthermore, some patients with migraine experience constant photophobia, even during headache-free intervals, leading to a compromised quality of life. This prospective, case-control study included 40 patients with migraine (18 male and 22 female) who were recruited at an eye hospital and eye clinic. The patients were divided into two groups: migraine with photophobia group, consisting of 22 patients (10 male and 12 female) with constant photophobia, and migraine without photophobia group, consisting of 18 patients (eight male and 10 female) without constant photophobia. We used 18F-fluorodeoxyglucose and positron emission tomography to compare cerebral glucose metabolism between the two patient groups and 42 healthy participants (16 men and 26 women). Compared with the healthy group, both the migraine with photophobia and migraine without photophobia groups showed cerebral glucose hypermetabolism in the bilateral thalamus (p < 0.05, family-wise error-corrected). Moreover, the contrast of migraine with photophobia minus migraine without photophobia patients showed glucose hypermetabolism in the bilateral medial thalamus (p < 0.05, family-wise error-corrected). The medial thalamus may be associated with the development of continuous photophobia in patients with migraine.

The association between glymphatic system dysfunction and alterations in cerebral function and structure in patients with white matter hyperintensities.

The objective of this study is to explore the relationship between the glymphatic system and alterations in the structure and function of the brain in white matter hyperintensity (WMH) patients. MRI data were collected from 27 WMH patients and 23 healthy controls. We calculated the along perivascular space (ALPS) indices, the anterior corner distance of the lateral ventricle, and the width of the third ventricle for each subject. The DPABISurf tool was used to calculate the cortical thickness and cortical area. In addition, data processing assistant for resting-state fMRI was used to calculate regional homogeneity, degree centrality, amplitude low-frequency fluctuation (ALFF), fractional amplitude of low-frequency fluctuation (fALFF), and voxel-mirrored homotopic connectivity (VMHC). In addition, each WMH patient was evaluated on the Fazekas scale. Finally, the correlation analysis of structural indicators and functional indicators with bilateral ALPS indices was investigated using Spearman correlation analysis. The ALPS indices of WMH patients were lower than those of healthy controls (left: t = -4.949, P < 0.001; right: t = -3.840, P < 0.001). This study found that ALFF, fALFF, regional homogeneity, degree centrality, and VMHC values in some brain regions of WMH patients were alternated (AlphaSim corrected, P < 0.005, cluster size > 26 voxel, rmm value = 5), and the cortical thickness and cortical area of WMH patients showed trend changes (P < 0.01, cluster size > 20 mm2, uncorrected). Interestingly, we found significantly positive correlations between the left ALPS indices and degree centrality values in the superior temporal gyrus (r = 0.494, P = 0.009, P × 5 < 0.05, Bonferroni correction). Our results suggest that glymphatic system impairment is related to the functional centrality of local connections in patients with WMH. This provides a new perspective for understanding the pathological mechanisms of cognitive impairment in the WMH population.

Neuroimaging profiles of the negative affective network predict anxiety severity in patients with chronic insomnia disorder: A machine learning study

BackgroundSleep is instrumental in safeguarding emotional well-being. While the susceptibility to both insomnia and anxiety has been demonstrated to involve intricate brain systems, the neuroimaging profile of chronic insomnia disorder with comorbid anxiety symptoms (CID-A) remains unexplored. Employing machine learning methodologies, this study aims to elucidate the distinct neural substrates underlying CID-A and to investigate whether these cerebral markers can prognosticate anxiety symptoms in patients with insomnia. MethodsFunctional magnetic resonance imaging (fMRI) data were procured from a relatively large cohort (dataset 1) comprised of 47 CID-A patients, 49 CID patients without anxiety (CID-NA), and 48 good sleeper controls (GSC). Aberrant cerebral functional alterations were assessed through functional connectivity strength (FCS) and resting-state functional connectivity (rsFC). Subsequently, Support Vector Regression (SVR) models were constructed to predict anxiety symptoms in CID patients based on neuroimaging features, which were validated utilizing an external cohort (dataset 2). ResultsIn comparison to CID-NA and GSC subjects, CID-A patients exhibited heightened FCS in the right dorsomedial prefrontal cortex (DMPFC), a central hub within the negative affective network. Moreover, the SVR models revealed that DMPFC-related rsFC/FCS features could be employed to predict anxiety symptoms in two independent cohorts of CID patients. LimitationModifications in brain functionality might vary across insomnia subtypes. ConclusionThe present findings suggest a potential negative affective network model for the neuropathophysiology of CID accompanied by anxiety. Importantly, the negative affective network pattern may serve as a predictor for anxiety symptoms in CID patients.

Blunted cerebral oxygenation during exercise in systemic lupus erythematosus patients.

Subclinical brain lesions have been reported in systemic lupus erythematosus (SLE) patients. Advanced neuroimaging techniques have revealed microstructural and microvascular alterations. Most studies examining structural or functional brain abnormalities were performed either at rest or during a mental task. Our study aimed to examine possible differences in cerebral oxygenation during exercise between SLE patients without known neuropsychiatric manifestations and age-matched controls, using near-infrared-spectroscopy (NIRS) and examine possible underlying mechanisms through evaluation of brain derived neurotrophic factor (BDNF) levels. The protocol involved a seated rest, a 3-min submaximal (30%) handgrip exercise, and a 3-min recovery. Continuous-NIRS was used to monitor changes in cerebral-oxygenated (O2Hb), de-oxygenated (HHb) and total-haemoglobin (tHb). BDNF levels were measured in serum samples. Twenty-six SLE patients and 27 matched controls were enrolled. No differences were observed in baseline characteristics. During exercise, cerebral-O2Hb increased in both groups. However, SLE patients exhibited a significantly lower average- (1.20 ± 0.89 vs. 2.69 ± 2.46, p=0.001) and peak-O2Hb response (2.89 ± 1.56 vs. 5.83 ± 4.59, p=0.004) compared to controls. Serum BDNF levels were significantly lower in SLE patients compared to controls (p<0.01). To our knowledge, this is the first study to evaluate cerebral oxygenation during exercise using NIRS in SLE patients compared to age-matched controls. Our data show that SLE patients even without overt neuropsychiatric manifestations exhibit a blunted increase in cerebral-O2Hb during a submaximal exercise stimulus. Examining brain oxygenation during a simple exercise task may assist in identifying patients with early alterations in cerebral function.

The Relationship between Side of Onset and Cerebral Regional Homogeneity in Parkinson's Disease: A Resting-State fMRI Study.

Objective Motor symptoms are usually asymmetric in Parkinson's disease (PD), and asymmetry in PD may involve widespread brain areas. We sought to evaluate the effect of asymmetry on the whole brain spontaneous activity using the measure regional homogeneity (ReHo) through resting-state functional MRI. Methods We recruited 30 PD patients with left onset (LPD), 27 with right side (RPD), and 32 controls with satisfactory data. Their demographic, clinical, and neuropsychological information were obtained. Resting-state functional MRI was performed, and ReHo was used to determine the brain activity. ANCOVA was utilized to analyze between-group differences in ReHo and the associations between abnormal ReHo, and various clinical and neuropsychological variables were explored by Spearman's correlation. Results LPD patients had higher ReHo in the right temporal pole than the controls. RPD patients had increased ReHo in the right temporal pole and decreased ReHo in the primary motor cortex and premotor area, compared with the controls. Directly comparing LPD and RPD patients did not show a significant difference in ReHo. ReHo of the right temporal pole was significantly correlated with depression and anxiety in RPD patients. Conclusions Both LPD and RPD have increased brain activity synchronization in the right temporal pole, and only RPD has decreased brain activity synchronization in the right frontal motor areas. The changed brain activity in the right temporal pole may play a compensatory role for depression and anxiety in PD, and the altered cerebral function in the right frontal motor area in RPD may represent the reorganization of the motor system in RPD.

Neck disability in patients with cervical spondylosis is associated with altered brain functional connectivity

Cervical degenerative disease is a major cause of neck disability, but it has been understudied in patients with cervical spondylotic (CS), largely due to the fact that the neurological impairment associated with this condition tends to be the primary treatment focus. This observational study examined the cerebral functional alterations occurring in advanced cervical spondylosis and myelopathy using resting state functional MRI. Associations between functional connectivity (FC) and neck disability using the Neck Disability Index (NDI) were assessed. Results of the study demonstrated an increase in FC with increasing in neck disability in regions associated with sensorimotor system (both postcentral gyri and precentral gyri, bilaterally, with the SMA; bilateral precentral gyri and the left postcentral gyrus, with the left superior frontal gyrus; bilateral SMA and the left putamen, with the superior frontal gyri). Accounting for the difference in neurological function (mJOA score), strong connectivity between the precentral gyri and the SMA associated with the neck disability. Consistent with studies in chronic pain conditions, these findings suggest neck disability is associated with altered cerebral FC in cervical spondylosis patients.

Cerebral functional abnormalities in patients with nasopharyngeal carcinoma after radiotherapy: an observational magnetic resonance resting-state study.

Background:Nasopharyngeal carcinoma (NPC) is sensitive to radiotherapy (RT). However, neurocognitive complications such as memory loss and learning and attention deficits emerge in the survivors of NPC who received RT. It remains unclear how radiation affects patient brain function. This pilot study aimed at finding cerebral functional alterations in NPC patients who have received RT.Methods:From September 2014 to December 2016, 42 individuals, including 22 NPC patients and 20 normal volunteer controls in National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences, and Peking Union Medical College, were recruited in this study. All patients received resting-state functional magnetic resonance imaging scans and neurocognitive tests 1 day before the initiation of RT (baseline) and 1 day after the completion of RT; the 20 normal controls were also subjected to the same scans and tests. The amplitude of the low-frequency fluctuations (ALFF) in blood oxygen level-dependent signals and functional connectivity (FC) were used to characterize cerebral functional changes. Independent t test, paired t test, and analysis of variances were used to obtain statistical significance across groups.Results:After RT, NPC patients showed significantly decreased ALFF values in the calcarine sulcus, lingual gyrus, cuneus, and superior occipital gyrus and showed significantly reduced FC mainly in the default mode network (P < 0.05, corrected by AlphaSim). Relative to the controls, ALFF was decreased in the lingual gyrus, calcarine sulcus, cingulate cortex, medial prefrontal gyrus (P < 0.05, corrected by AlphaSim), and FC reduction was found in multiple cerebellar–cerebral regions, including the cerebellum, parahippocampus, hippocampus, fusiform gyrus, inferior frontal gyrus, inferior occipital gyrus, precuneus, and cingulate cortex (P < 0.001, corrected by AlphaSim).Conclusions:Cerebral functional alterations occur immediately after RT. This study may provide an explanation for the cognitive deficits in the morphologically normal-appearing brains of NPC patients after RT and may contribute to the understanding of the complex mechanism of RT.

Effects of Chronic Consumption of Sugar-Enriched Diets on Brain Metabolism and Insulin Sensitivity in Adult Yucatan Minipigs

Excessive sugar intake might increase the risk to develop eating disorders via an altered reward circuitry, but it remains unknown whether different sugar sources induce different neural effects and whether these effects are dependent from body weight. Therefore, we compared the effects of three high-fat and isocaloric diets varying only in their carbohydrate sources on brain activity of reward-related regions, and assessed whether brain activity is dependent on insulin sensitivity. Twenty-four minipigs underwent 18FDG PET brain imaging following 7-month intake of high-fat diets of which 20% in dry matter weight (36.3% of metabolisable energy) was provided by starch, glucose or fructose (n = 8 per diet). Animals were then subjected to a euglycemic hyperinsulinemic clamp to determine peripheral insulin sensitivity. After a 7-month diet treatment, all groups had substantial increases in body weight (from 36.02±0.85 to 63.33±0.81 kg; P<0.0001), regardless of the diet. All groups presented similar insulin sensitivity index (ISI = 1.39±0.10 mL·min-1·μUI·kg). Compared to starch, chronic exposure to fructose and glucose induced bilateral brain activations, i.e. increased basal cerebral glucose metabolism, in several reward-related brain regions including the anterior and dorsolateral prefrontal cortex, the orbitofrontal cortex, the anterior cingulate cortex, the caudate and putamen. The lack of differences in insulin sensitivity index and body weight suggests that the observed differences in basal brain glucose metabolism are not related to differences in peripheral insulin sensitivity and weight gain. The differences in basal brain metabolism in reward-related brain areas suggest the onset of cerebral functional alterations induced by chronic consumption of dietary sugars. Further studies should explore the underlying mechanisms, such as the availability of intestinal and brain sugar transporter, or the appearance of addictive-like behavioral correlates of these brain functional characteristics.

Functional alterations of pain processing pathway in migraine patients with cutaneous allodynia.

Cutaneous allodynia (CA) is a characteristic of central sensitization, predicting migraine progression, and poor response to therapy. The present study aimed to find out the cerebral functional alterations related to the establishment of central sensitization in migraineurs using functional magnetic resonance imaging (fMRI). The experiment was performed in 15 migraineurs with Cutaneous allodynia (MWCA) and 19 patients without Cutaneous allodynia (MWoCA) in the interictal phase, and 20 matched healthy controls. Blood oxygen level dependent-fMRI was applied in all subjects when they were given transcutaneous electrical nerve stimulation at the left medial forearm, achieving to a predetermined level of pain sensation (i.e., visual analogue scale [VAS] = 40). Contrast images were then produced to determine whether this disorders present functional changes in the brain during pain processing. Demographic and headache characteristics were balanced between groups. The contrast images of both migraine groups comparing to healthy controls exhibited weaker activation of various brain regions (e.g., cerebellum and insulae), which might be relevant to the pathophysiological procedure of migraine. The direct comparison between the two migraine groups revealed that activation in the dorsal pons and contralateral (right) inferior parietal lobule of MWCA subjects were significantly lower than it in MWoCA ones. The interictal dysfunction of pain processing pathway may be responsible for (at least relevant to) central sensitization in migraine patients, via abnormal modulations of nociceptive transmission.

Impact of early stages of (mild) hepatitis C viral infection on neurocognitive functions in otherwise healthy patients: an Egyptian magnetic resonance spectroscopy study

Background The alterations in cerebral function in patients with chronic hepatitis C virus (HCV) infection may be due to a direct effect of HCV on the brain, or due to neurotoxic-related systemic inflammation. Objective This study aimed to assess central nervous system involvement through brain magnetic resonance spectroscopy (MRS) as well as cognitive functions in HCV-infected patients with mild liver disease. Patients and methods Twenty-eight HCV-infected patients with slightly elevated liver enzymes were recruited from the outpatient Hepatology Clinic, Beni Sweif University Hospitals and Ain Shams University Hospitals. They underwent cognitive examination by means of the Wechsler attention, concentration, and memory subscales, as well as cerebral MRS. The results of all investigations were compared with corresponding results of 15 matched normal controls. Results The results showed mild but significant elevation of liver enzymes in the patient group compared with the control group with impaired levels of attention, concentration, and memory determined by the subscales. MRS findings showed elevated choline and myoinositol in the basal ganglia, decreased N -acetyl aspartate, and abnormal N -acetyl aspartate/creatine ratio. Conclusion Treatment plans for HCV should consider neuropsychological complications.

Assessment of Executive Functions in Chronic Hepatitis C Virus Infected Patients

Background: Chronic infection with HCV is one of the most important causes of chronic liver disease, which can progress to cirrhosis and hepatocellular carcinoma (HCC). It is well established that advanced forms of the disease are accompanied by overt and global cognitive deficits (hepatic encephalopathy) but now there is a growing evidence that the alterations in cerebral function in patients with chronic HCV infection may appear long before the development of severe liver cirrhosis, it has been hypothesized that it is related to a direct effect of HCV on the brain; or the neurotoxic effect of HCV-related systemic inflammation. Aim: The purpose of the study was to assess the possible existence of executive dysfunction in chronic HCV infected patients without cirrhosis. Study design: case control study. Participants: 100 elderly patients aged 60 years and above, 50 patients are HCV positive (cases) and 50 patients are HCV negative (controls) both groups have no liver cirrhosis. Methods: All participants were subjected to the following: Diagnosis of HCV by detection of HCV ab using ELISA technique, non invasive assessment of liver cirrhosis using abdominal ultrasound, and evaluation of executive functions using 5 neuropsychological tests (block design, digit span backwards, animal verbal fluency, clock drawing, and EXIT 25). Results: The study showed that there is a significant difference between cases and controls regarding Exit 25 and Digit span backwards tests scores indicating affection of the phonological loop component of working memory among HCV positive patients. Conclusion: Executive functions are affected in patients with chronic HCV infection without liver cirrhosis.

Dysexecutive Performance of Elderly Patients with Chronic Hepatitis C Virus Infection

Chronic infection with hepatitis C virus (HCV) is one of the most important causes of chronic liver disease, which can progress to cirrhosis and hepatocellular carcinoma (HCC). It is well established that advanced forms of the disease are accompanied by overt and global cognitive deficits (hepatic encephalopathy) but now there is a growing evidence that the alterations in cerebral function in patients with chronic HCV infection may appear long before the development of severe liver cirrhosis, it has been hypothesized that it is related to a direct effect of HCV on the brain; or the neurotoxic effect of HCV-related systemic inflammation. The purpose of the study was to assess the possible existence of executive dysfunction in chronic HCV infected patients. One hundred elderly patients aged 60 years and above agreed to participate in this study; 50 patients were HCV positive (cases) and 50 patients were HCV negative (controls). All participants were subjected to the following: diagnosis of HCV by detection of HCV antibodies using ELISA technique, non-invasive assessment of liver condition, and evaluation of executive functions using 5 neuropsychological tests. The study showed that there was a significant difference between cases and controls regarding 2 executive function tests related to the phonological loop component of working memory among HCV positive patients. The study concluded that chronic HCV infection is accompanied by dysexecutive performance.

β2 Integrin–Mediated Crawling on Endothelial ICAM-1 and ICAM-2 Is a Prerequisite for Transcellular Neutrophil Diapedesis across the Inflamed Blood–Brain Barrier

In acute neuroinflammatory states such as meningitis, neutrophils cross the blood-brain barrier (BBB) and contribute to pathological alterations of cerebral function. The mechanisms that govern neutrophil migration across the BBB are ill defined. Using live-cell imaging, we show that LPS-stimulated BBB endothelium supports neutrophil arrest, crawling, and diapedesis under physiological flow in vitro. Investigating the interactions of neutrophils from wild-type, CD11a(-/-), CD11b(-/-), and CD18(null) mice with wild-type, junctional adhesion molecule-A(-/-), ICAM-1(null), ICAM-2(-/-), or ICAM-1(null)/ICAM-2(-/-) primary mouse brain microvascular endothelial cells, we demonstrate that neutrophil arrest, polarization, and crawling required G-protein-coupled receptor-dependent activation of β2 integrins and binding to endothelial ICAM-1. LFA-1 was the prevailing ligand for endothelial ICAM-1 in mediating neutrophil shear resistant arrest, whereas Mac-1 was dominant over LFA-1 in mediating neutrophil polarization on the BBB in vitro. Neutrophil crawling was mediated by endothelial ICAM-1 and ICAM-2 and neutrophil LFA-1 and Mac-1. In the absence of crawling, few neutrophils maintained adhesive interactions with the BBB endothelium by remaining either stationary on endothelial junctions or displaying transient adhesive interactions characterized by a fast displacement on the endothelium along the direction of flow. Diapedesis of stationary neutrophils was unchanged by the lack of endothelial ICAM-1 and ICAM-2 and occurred exclusively via the paracellular pathway. Crawling neutrophils, although preferentially crossing the BBB through the endothelial junctions, could additionally breach the BBB via the transcellular route. Thus, β2 integrin-mediated neutrophil crawling on endothelial ICAM-1 and ICAM-2 is a prerequisite for transcellular neutrophil diapedesis across the inflamed BBB.

Effect of vagus nerve stimulation on focal transient cerebral ischemia and reperfusion in adult male white new zealand rabbits

Background: Oxidative stress has been implicated in the pathophysiology of cerebral ischemia. Pentraxin-3 plays an important role in innate immune responses and in inflammatory diseases. Our aim was to evaluate pentraxin-3 serum level on focal transient cerebral ischemia and reperfusion model in rabbits and to assess the anti-inflammatory and anti-oxidant effects of vagus nerve stimulation. Materials and methods: Focal transient cerebral ischemia and reperfusion was induced by occlusion of the right common carotid artery for 2 hours followed by reperfusion for one hour. Stimulating electrodes were implanted on the cervical part of the right vagus nerve. Vagus nerve stimulation was started 30 min following right common carotid artery ligation for a period of one hour. The stimulation signals were delivered every five minutes for 30 seconds. All the procedures were duplicated but no stimulus was delivered in the control group. Serum level of pentraxin-3, lipid peroxide and total thiols were determined at baseline, at end of ischemia and at end of reperfusion and the animal decapitated and neuronal damage was evaluated. Results: We found that vagus nerve stimulation caused reduction of the ischemic features with revival of the cell shape and size. It also resulted in decreased serum levels of pentraxin-3 and lipid peroxide whereas the level of total thiols was increased. Conclusion: We concluded that the observed diversity in pentraxin-3, lipid peroxide and total thiols serum levels in cerebral ischemia and reperfusion may reflect relative roles in the biology. Anti-inflammatory and anti-oxidant role of vagus nerve stimulation in cerebral ischemia and reperfusion may represent a marker of altered cerebral function, and may provide potential therapeutic applications.

Gender differential effects of developmental exposure to methyl-mercury, polychlorinated biphenyls 126 or 153, or its combinations on motor activity and coordination

Polychlorinated biphenyls (PCBs) and methylmercury (MeHg) are persistent organic pollutants accumulating in the food chain. Pre- and neonatal exposure to these neurotoxicants may affect brain development and lead to long-lasting alterations in cerebral function, which can result in motor alterations in youth and/or adulthood. Some neurotoxicants induce gender specific effects.The aims of the present work were to: (1) assess the effects of developmental exposure to MeHg, PCB 153 or PCB 126 on spontaneous locomotor and vertical activity and motor coordination when the rats are 2-month old; (2) assess whether perinatal exposure to combinations of MeHg with PCB153 or PCB126 alter the effects of the individual neurotoxicants; (3) follow the progression of motor alterations when the rats are 3-, 5- and 7-month old; (4) assess if the effects are similar or different in males and females.Pregnant rats were treated with MeHg (0.5mg/kgday); PCB126 (100ng/kgday) or PCB153 (1mg/kgday) or with combinations of MeHg with each PCB, administered in food from gestational day 7 until weaning at post-natal day 21.PCB 126 impaired motor coordination at 2 months in males but not in females. PCB 153 impaired coordination both in males and females. Combinations of MeHg with PCB153 or PCB126 did not affect motor coordination, indicating that MeHg counteracts the effects of the PBCs.The combination of MeHg and PCB153 induces hypolocomotion at 2 months but hyperactivity at 7 months while the individual compounds did not induce any effect. PCB126 induced gender selective effects, reducing locomotor activity at 2 months in females but not in males. The combination of MeHg and PCB126 behaves as PCB126 alone.All compounds and combinations tested induce gender-selective alterations in vertical activity. The effects on locomotor and vertical activity change with age in the same rats. At 2 months all compounds and combinations reduce vertical activity in females but not in males. At 7 months all treatments induced hyperactivity both in males and females, except MeHg+PCB126.In conclusion, the results show that: (a) many motor alterations induced by most compounds are different in males and females; (b) mixtures of MeHg with PCBs 153 or 126 induce different effects that the individual compounds; (c) different types of motor activity (spontaneous locomotion, vertical activity and motor coordination) are affected differently by the same neurotoxicant or mixture; and (d) the effects on locomotor and specially on vertical activity change with the age of the rat. Most compounds reduce activity at youth (2 months) and induce hyperactivity at adulthood (5–7 months). The change from hypo- to hyperactivity occurs earlier in males.

Cerebral blood flow velocity in sleep

Sleep is the most conspicuous alteration of cerebral function during the circadian rhythm. It is composed of a cyclic sequence of stages defined on the basis of electrophysiological parameters. The underlying functional activity of the human brain is reflected by sleep correlated changes of cerebral blood flow (CBF), CBF velocity and cerebral metabolism (CM). Transcranial Doppler sonography (TCD) allows to analyze the rapid adaptation processes of cerebral hemodynamics due to TCD capabilities for high temporal resolution and continuous recording during sleep using modern ultrasonic probes with special fixation devices. After the onset of sleep there is a significant progressive reduction of CBF velocity from the waking state to slow wave sleep. The beginning of REM sleep is accompanied by a marked increase in CBF velocity. Furthermore, TCD enables the assessment of perfusion changes in pathological sleep conditions. In sleep apnea syndrome an apnea-associated increase in CBF velocity occurs, which is attributed to apnea-related hypercapnia, whereas a rapid normalization of flow velocity occurs at the end of each apneic episode. TCD is a useful method for long-term and on-line monitoring of dynamic changes in cerebral perfusion during normal sleep and in sleep disorders.

Caracterización psicométrica, motora y funcional en niños con parálisis cerebral

ABSTRACTPsychometric, motor and functional description in children with cerebral palsyIntroduction: Cerebral Palsy (CP), the most frequent cause of chronic motor disability among children, is often associated to other alterations of cerebral function, among them cognitive function. International pu-blications show up to 70% of children with CP have normal intelligence (IQ). Objective: Determine IQ and motor function in a group of children with CP. Methodology: Prospective descriptive study of 34 children with CP, classifi ed according to type. Psychometric and motor tests were applied. Results: Of these children, 44% presented tetraparetic CP, 21% diparetic, 35% hemiparetic. Among tetraparetic children, 33% showed normal IQ, 14% mild Mental Retardation (MR), 53% severe MR. Among diparetic children, normal IQ, mild MR, severe MR showed in a frequency of 57%, 14% y 29% respectively. Children with hemiparesis showed normal IQ in 92% and mild MR in 8%. Motor function was usually proportional to IQ.

Iopromide-induced encephalopathy following coronary angioplasty

Non-ionic agents have pharmacological side effects, such as seizure, alteration of cerebral function, confusion, short-term memory loss, mental aberrations and ophthalmoplegia. In this report, we present two cases that developed contrast-induced encephalopathy following coronary angioplasty by the non-ionic contrast agent, iopromide (Ultravist(®)). As a result, we concluded that iopromide-induced encephalopathy may occur during angioplasty in patients with no particular predispositions. In addition to that, contrast-induced encephalopathy should be considered as a new-onset neurological disorder.

Comparative study on carotid revascularization (endarterectomy vs stenting) using markers of cellular brain injury, neuropsychometric tests, and diffusion-weighted magnetic resonance imaging

Subclinical alterations of cerebral function can occur during or after carotid revascularization and can be detected by a variety of standard tests. This comparative study assessed the relationship among serum levels for two biochemical markers of cerebral injury, postoperative diffusion-weighted magnetic resonance imaging (DW-MRI), and neuropsychometric testing in patients undergoing carotid endarterectomy (CEA) or carotid artery stenting (CAS) for high-grade asymptomatic carotid stenosis. Forty-three consecutive asymptomatic patients underwent carotid revascularization by endarterectomy (CEA, 20) or stenting (CAS, 23). They were evaluated with DW-MRI and the Mini-Mental State Examination (MMSE) test preoperatively and <or=24 hours after carotid revascularization. Venous blood samples to assess serum levels of neuron-specific enolase (NSE) and S100beta protein were collected for each patient preoperatively and five times in a 24-hour period postoperatively and assayed using automated commercial equipment. The MMSE test was repeated at 6 months. The relationship between serum marker levels and neuropsychometric and imaging tests and differences between the two groups of patients were analyzed by chi(2) test, with significance at P < .05. No transient ischemic attacks or strokes were clinically observed. CAS caused more new subcortical lesions at postoperative DW-MRI and a significant decline in the MMSE postoperative score compared with CEA (P = .03). In CAS patients, new lesions at DW-MRI were significantly associated with a postoperative MMSE score decline >5 points (P = .001). Analysis of S100beta and NSE levels showed a significant increase at 24 hours in CAS patients compared with CEA patients (P = .02). The MMSE score at 6 months showed a nonsignificant increase vs the postoperative score in both groups. Biochemical markers measurements of brain damage combined with neuropsychometric tests and DW-MRI can be used to evaluate silent injuries after CAS. The mechanisms of rise in S100beta and NSE levels at 24 hours after CAS may be due to increased perioperative microembolization rather than to hypoperfusion. Further studies are required to assess the clinical significance of those tests in carotid revascularization.

SS35. Comparative Study on Carotid Revascularization (CEA Versus CAS) Using Markers of Cellular Brain Injury, Neuropsychometric Tests and DW-MRI

Subclinical alterations of cerebral function can occur during or after carotid revascularization and can be predict by simple tests administration. The aim of this comparative study is to assess the relationship between serum level of two biochemical markers of cerebral injury and post-operative DW-MRI and neuropsychometric testing (MMSE test) in two groups of patients submitted to carotid revascularization for high-grade stenosis.