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Competing Interests: None

Background: Electromagnetic fields (EMFs) emitted by cellular telephones may cause neurological ill effects like cognitive dysfunction, emotional instability, and even brain tumors. Slowing of brain activity on electroencephalography (EEG) has been shown. However, these findings need further validation., Aims: EEG changes and adverse effects experienced following cell-phone use were studied., Settings and Design: The study was conducted in the Department of Neurology of a tertiary care university hospital in India on North Indian students of the University, from August 2017 to October 2017., Materials and Methods: Twenty-one students underwent video-EEG recording before and after application of Samsung GT-56312 dual SIM smart phone in switched off, switched on, and switched on mode with conversation., Statistical Analysis Used: Average EEG frequencies and amplitudes were calculated for different brain regions. Chi-square tests and t-tests were used for comparison between variables., Results: The mean age of 7 (33.3%) male and 14 (66.7%) female subjects was 20.76 ± 1.48 years. The average EEG frequencies following mobile phone application with conversation were higher and the amplitudes lower than the baseline values. Frequencies were greater on the right side. Slow waves were detected in the frontal region in 38.1%, in the parietal region in 33.3%, in the occipital and temporal region in 19.1%; and, generalized slow waves were seen in 9.5% students. During the experiment, 23.8% experienced headache, 19% experienced irritation, and 9.5% felt drowsy. Headache and loss of concentration (33.3%), sleep disturbances (28.6%), and fatigue (19%) were frequent in daily life., Conclusions: Experimental application of mobile phones may lead to some EEG changes and certain ill effects on the well-being. Hence, prolonged use of these gadgets warrants caution., Competing Interests: None

Dengue encephalitis and dengue encephalopathy are frequent neurological complications of systemic dengue virus infection. Neuroimaging is normal in approximately 50% of patients. Common imaging abnormalities involve periventricular structures, including the basal ganglion, thalamus, and periventricular white matter. We describe an unusual case of dengue encephalopathy with unilateral imaging abnormalities involving the right cerebral hemisphere and mimicking the involvement of the right middle cerebral artery.

Posterior reversible encephalopathy syndrome is characterized by acute headache, visual impairment, seizures, and altered mental status; neuroimaging may show cerebral edema affecting the parietal and occipital lobes of the brain. The objective of this article is to review the current understanding of posterior reversible encephalopathy syndrome in eclampsia. Literature was searched from PubMed, Scopus, and Google Scholar databases. The search terms included "eclampsia", "eclampsia and posterior reversible encephalopathy syndrome", and "pregnancy and posterior reversible encephalopathy syndrome". We reviewed all published original articles with the search term "posterior reversible encephalopathy syndrome". Up to 100% of eclamptic patients may have reversible posterior leukoencephalopathy syndrome. Two putative mechanisms - "vasogenic" and "vasospasm" - are considered to be responsible. Cerebral edema and petechial cortical hemorrhages are common autopsy findings. Clinical and neuroimaging manifestations are reversible in the majority of patients. Prompt correction of increased blood pressure and treatment of seizures are the cornerstones of treatment. Magnesium sulfate is the drug of choice for seizures. Some survivors may have permanent vision loss and other disabling sequelae. In conclusion, posterior reversible encephalopathy is a devastating complication of eclampsia. Early recognition helps in preventing some of its devastating sequelae., Competing Interests: There are no conflicts of interest

Delayed brain development in perinatally HIV-infected children may affect the functional brain activity and subsequently cognitive function. The current study evaluated the functional brain activity in HIV-infected children by quantifying the amplitude of low frequency fluctuations (ALFF) and functional connectivity (FC). Additionally, correlation of ALFF and FC with cognitive measures was performed. Twenty-six HIV-infected children and 20 control children underwent neuropsychological (NP) assessment and resting-state functional magnetic resonance imaging (rs-fMRI). ALFF and FC maps were generated and group differences were analyzed using two-sample t-test. Furthermore, ALFF and FC showing significant group differences were correlated with NP scores using Pearson's correlation. Significantly lower ALFF in the left middle temporal gyrus, precentral and post central gyrus was observed in HIV-infected children compared to controls. FC was significantly reduced in the right inferior parietal, vermis, middle temporal and left postcentral regions, and significantly increased in the right precuneus, superior parietal and left middle frontal regions in HIV-infected children as compared to control. HIV-infected children showed significantly lower NP scores in various domains including closure, exclusion, memory, verbal meaning, quantity and hidden figure than controls. These waning cognitive functions were significantly associated with changes in ALFF and FC in HIV-infected children. The findings suggest that abnormal ALFF and FC may responsible for cognitive deficits in HIV-infected children. ALFF and FC in association with cognitive evaluation may provide a clinical biomarker to evaluate functional brain activity and to plan neurocognitive intervention in HIV-infected children undergoing standard treatment., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Solitary calcified neurocysticercosis is a common cause of seizures in the developing countries. Factors responsible for seizure recurrence in patients with solitary calcified neurocysticercosis are not known. We evaluated the clinical, neuroimaging and biochemical predictors of seizure recurrence., Methods: This was a prospective observational study. Patients with new-onset seizures and a solitary calcified neurocysticercosis were included. Patients were evaluated clinically; baseline electroencephalography and magnetic resonance imaging of brain were done for all patients.. The patients were followed for 1year. Seizure recurrence was defined as the recurrence of an episode of seizure at least 1 week after the initiation of the anti-epileptic drugs., Results: Fifty-four patients with a mean age of 20.43±7.34years were included. Thirteen patients developed seizure recurrence during the follow-up period. On univariate analysis, status epilepticus at presentation (p=0.025), size of the lesion >10mm (p=0.015), presence of perilesional edema (p<0.001) and scolex (p=0.033) were significantly associated with seizure recurrence. On multivariate analysis, only presence of perilesional edema (p=0.018, odds ratio=12.122, 95% confidence interval 1.521-96.639) was an independent predictor of seizure recurrence., Conclusion: Status epilepticus at presentation is associated with an increased risk of seizure recurrence. Neuroimaging features like presence of perilesional edema and scolex can similarly predict seizure recurrence. These neuroimaging features can serve as potential surrogate markers to define therapy in these patients. The findings of our study might be helpful in stratifying patients with a higher risk of seizure recurrence, especially those who may require a more aggressive management., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Pediatric HIV patients often suffer with neurodevelopmental delay and subsequently cognitive impairment. While tissue injury in cortical and subcortical regions in the brain of adult HIV patients has been well reported there is sparse knowledge about these changes in perinatally HIV infected pediatric patients. We analyzed cortical thickness, subcortical volume, structural connectivity, and neurocognitive functions in pediatric HIV patients and compared with those of pediatric healthy controls. With informed consent, 34 perinatally infected pediatric HIV patients and 32 age and gender matched pediatric healthy controls underwent neurocognitive assessment and brain magnetic resonance imaging (MRI) on a 3 T clinical scanner. Altered cortical thickness, subcortical volumes, and abnormal neuropsychological test scores were observed in pediatric HIV patients. The structural network connectivity analysis depicted lower connection strengths, lower clustering coefficients, and higher path length in pediatric HIV patients than healthy controls. The network betweenness and network hubs in cortico-limbic regions were distorted in pediatric HIV patients. The findings suggest that altered cortical and subcortical structures and regional brain connectivity in pediatric HIV patients may contribute to deficits in their neurocognitive functions. Further, longitudinal studies are required for better understanding of the effect of HIV pathogenesis on brain structural changes throughout the brain development process under standard ART treatment.

Introduction: The resting state functional MRI (rsfMRI) approach is useful to explore the brain's functional organization in health and disease conditions. In this study, using rsfMRI the alteration in brain due to vitamin B12 deficiency and reversibility of these alterations following therapy was studied., Methods: Thirteen patients with clinical and biochemical evidence of vitamin B12 deficiency were recruited in this study. Fifteen age and sex matched healthy controls were also included. Patients and controls were clinically evaluated using neuropsychological test (NPT). The analysis was carried out using regional homogeneity (ReHo) and low frequency oscillations (LFO) of BOLD signals in resting state. Six patients were also evaluated with rsfMRI and NPT after 6 weeks replacement therapy., Results: ReHo values in patients with vitamin B12 deficiency were significantly lower than controls in the entire cerebrum and the brain networks associated with cognition control, i.e., default mode, cingulo-opercular and fronto-parietal network. There was no significant difference using LFO and it did not show significant correlations with NPT scores. ReHo showed significant correlation with NPT scores. All the 6 patients showed increase in ReHo after replacement therapy., Conclusion: We conclude that brain networks associated with cognition control are altered in patients with vitamin B12 deficiency, which partially recover following six weeks of replacement therapy. This is the first study to evaluate the rsfMRI in the light of clinical neuropsychological evaluation in patients. rsfMRI may be used as functional biomarker to assess therapeutic response in vitamin B12 deficiency patients., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Introduction: Vitamin B12 deficiency may cause neural tissue damage. Even in advanced stages, conventional imaging of brain usually appears normal in vitamin B12 deficient patients. The aim of this study was to assess the structural and functional changes in brain of patients with vitamin B12 deficiency before and after six weeks of vitamin B12 supplementation using diffusion tensor imaging and pseudo-continuous arterial spin labelling (PCASL)., Methods: MR imaging including DTI and PCASL and neuropsychological tests (NPT) were performed in 16 patients with vitamin B12 deficiency and 16 controls before and after 6weeks of therapy. Cerebral blood flow (CBF) derived from PCASL and DTI indices was calculated in brain of patients with vitamin B12 deficiency and controls., Results: Patient with vitamin B12 deficiency showed altered neuropsychological scores and altered CBF as well as fractional anisotropy (FA) values in various brain regions as compared with controls. Both CBF values and neuropsychological scores showed complete reversibility at 6weeks post therapy. Though FA values showed significant recovery, it failed to show complete recovery., Conclusion: Our results suggest that micro-structural recovery lags behind functional recovery in patients with vitamin B12 deficiency following therapy and CBF change may be used as an early predictor of complete recovery in patients with B12 deficiency., (Copyright © 2015. Published by Elsevier Inc.)

Background and Purpose: Posterior reversible encephalopathy syndrome is associated with eclampsia. We assessed the distribution and nature of typical and atypical cranial MR imaging findings in these patients and their correlation with clinical and laboratory data and predictors of outcome., Materials and Methods: Forty-five clinically confirmed cases of eclampsia were included in this prospective observational study. Subjects with hemolysis, elevated liver enzymes, and low platelets syndrome (n = 9) and pre-existing neurologic conditions (1 with cerebral solitary cysticercus granuloma) were excluded. Patients underwent blood investigations and cranial MR imaging., Results: Twenty-seven patients had abnormal while 8 had normal MR imaging findings. Involvement of brain regions was as follows: frontal, 88.89%; temporal, 44.44%; parietal, 100%; occipital, 100%; deep gray matter, 29.63%; cerebellum, 22.22%; brain stem, 14.81%. Cytotoxic edema was present in 33.33% of cases; 66.67% of patients had mild posterior reversible encephalopathy syndrome; 25.92% had moderate posterior reversible encephalopathy syndrome; and 7.41% had severe posterior reversible encephalopathy syndrome. Abnormal neuroimaging findings were significantly associated with altered sensorium; visual disturbances; status epilepticus; and elevated serum creatinine, uric acid, and lactate dehydrogenase (P=.006, P=.018, P=.015, P=.019, P=.003, and P=.001, respectively). Serum creatinine, uric acid, and lactate dehydrogenase values and the presence of moderate or severe posterior reversible encephalopathy syndrome were significantly associated with mortality (P<.001, P<.001, P=.009, and P=.027, respectively)., Conclusions: Neuroimaging in eclampsia demonstrates a higher incidence of atypical distributions and cytotoxic edema than previously thought. Altered sensorium; visual disturbances; status epilepticus; and elevated serum uric acid, lactate dehydrogenase, and creatinine are associated with abnormal neuroimaging findings. Higher serum creatinine, uric acid, and lactate dehydrogenase levels and moderate and severe forms of posterior reversible encephalopathy syndrome are possible predictors of poor outcome., (© 2014 by American Journal of Neuroradiology.)

Introduction: Diffusion tensor tractography (DTT) is a newer magnetic resonance imaging (MRI) technique that helps in evaluation of white matter. Presurgical planning with tractography may be valuable for evaluation of white matter tracts and their relationship with epileptogenic focus and for evaluation of cortical fibres around the epileptogenic zone., Methods: This study was carried out on 33 patients diagnosed with medically refractory epilepsy (males, 27; females, 6) with a mean age of 31.93 (range: 19-50) years. Twenty age and sex matched controls were also included. DTT evaluation was done using a 3.0 TexlaMRI scanner. Single-shot spin-echo echo-planar imaging (with 32-different diffusion gradient directions) was acquired for reconstruction of the white matter tracts. Diffusion metrics within fibre bundles that were reconstructed by a continuous fibre-track algorithm were compared between groups., Results: Patients had either partial seizures (21 patients; simple partial, complex partial or secondarily generalized seizure) or generalized seizures (12 patients; tonic clonic, tonic or myoclonic). Out of the 33 patients, 23 patients were classified into the lesional group and the rest into the non-lesional group. The lesions observed on conventional MRI included focal gliosis, hippocampal sclerosis, post-hypoxic encephalopathy, calcification and post-traumatic cavitation, in various parts of the brain. Significant differences were observed in terms of fractional anisotropy and mean diffusivity values amongst controls and patients, as well as on the lesional and non-lesional side of the brain; patients with a normal conventional imaging showed fractional anisotropy and mean diffusivity changes as well., Conclusion: We conclude that widespread diffusion abnormalities occur in the white matter tracts on the side of lesion as well as distant from the epileptic focus., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Foot-drop is a rare but important manifestation of intracranial pathologies ranging from space-occupying lesions to cerebrovascular accidents. Being most commonly associated with peripheral nerve lesions or radicular compressions, it remains an underappreciated feature of central-structural abnormalities. We describe an interesting case of a 14-year-old boy who had presented with acute onset right-sided foot-drop due to a left-sided parasagittal neurocysticercus lesion, without seizures and discuss the location of the lesion in the precentral area in reference to Penfield's motor homunculus.

Subacute sclerosing panencephalitis (SSPE) is a progressive, devastating neurologic disorder caused by mutant measles virus. In this study we evaluated the prognostic value of neuroimaging abnormalities in SSPE. Thirty consecutive patients with SSPE were included. Diagnosis of SSPE was based on the criteria described by Dyken. Patients were followed for 6 months. Neuroimaging studies were performed at inclusion and after 6 months. Regression or progression of the disease was defined as a change of one, or more than one, stage in Jabbour's staging system. Degree of disability was assessed using the modified Rankin scale (mRS) score. Neuroimaging abnormalities were seen in 27 patients. Dominant imaging abnormalities were cerebral atrophy, white matter signal changes, cortical grey matter abnormalities and signal change in the basal ganglia. After 6 months of follow-up, 18 (60%) patients had a poor outcome (mRS score: 3-6); one patient died. The remaining 12 patients (40%) had a stabilized clinical condition (mRS score: 0-2). On univariate analysis, predictors of death or disability were: poor mRS score at baseline (p = 0.003) and Jabbour's clinical stage III (p = 0.019). None of the neuroimaging abnormalities were associated with a poor prognosis or clinical deterioration (p > 0.05). We conclude that we did not observe any association between cerebral neuroimaging at baseline and neurological outcome after 6 months in patients with SSPE., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Introduction: The symptomatic central nervous system involvement is often seen in patients with miliary tuberculosis., Materials and Methods: In this study, we evaluated 60 consecutive miliary tuberculosis patients, who presented with some neurological manifestations. Evaluation included neurological examination, a battery of blood tests, HIV serology, sputum examination, cerebrospinal fluid (CSF) examination along with imaging of the brain and spinal cord. The patients were followed up after completion of 6 months of antituberculous treatment., Results: Patients ranged between 14 and 53 years in age. Three patients tested HIV positive. Forty-eight (80%) patients had tuberculous meningitis. In 12 (20%) patients, the CSF examination was normal. In 27 patients with tuberculous meningitis, neuroimaging revealed intracerebral tuberculoma. Fourteen patients showed multiple tuberculomas, while 7 had a solitary tuberculoma. In six patients, the tuberculomas were small and numerous. In two patients, neuroimaging revealed a spinal tuberculoma. For three patients with tuberculous brain masses, the CSF was normal. Nine (15%) patients presented with myelopathy. Three patients exhibited Pott's paraplegia. Three patients had transverse myelitis (with normal neuroimaging). In three patients, the spinal MRI revealed an intramedullary tuberculoma. On follow-up, 15 (25%) patients expired. Thirty-one (52%) patients showed significant improvement. Eight patients (13%) showed nil or partial recovery. Six of the patients with no improvement developed vision loss. Six (10%) patients were lost to follow up., Conclusion: A variety of neurological complications were noted in military tuberculosis patients, tuberculous meningitis and cerebral tuberculomas being the most frequent complications. However, a majority of patients improved following antituberculous treatment.

This study was planned to observe the clinical and radiological course of single small enhancing CT lesions in Indian patients presenting with new-onset-seizures. In this study, 75 patients with new-onset seizures and a single enhancing CT lesion were prospectively followed up for 1 year. All patients fulfilled the criteria of cysticercus granuloma. The repeat CT scans were performed 2 months after the first CT scan. Antiepileptic drug therapy was the only form of treatment given. The majority of patients were below 20 years of age. Simple partial seizure, with or without secondary generalization, was the commonest type of seizure encountered in these patients. In follow-up CT scans 84% of patients showed either disappearance or regression in the size of lesion. The proportion of patients showing complete disappearance of CT lesions was 0.73 (95% CI, 0.61-0.80). In 11 (15%) patients the lesions were calcified. In nine patients, in whom the lesion had persisted or regressed, another follow-up CT scan (6 months after the second scan) revealed either complete disappearance or calcification of the lesions. The majority (86.6%) of patients remained seizure free for 1 year after starting antiepileptic drugs. Ten patients experienced seizure recurrences within the first month of therapy. The proportion of patients who remained seizure free was 0.86 (95% CI, 0.76-0.92). Four patients experienced seizure recurrence even after complete disappearance of CT lesions. In the majority of patients the lesions disappeared spontaneously and in a few the lesions calcified; hence these patients did not require anticysticercal therapy. Antiepileptic therapy was helpful in controlling further recurrences of seizures in most of the patients. A few patients experienced seizures even after disappearance of CT lesions., (Copyright 2001 BEA Trading Ltd.)