Displaying publications 41 - 60 of 218 in total

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  1. Arumugam A, A Rahman NA, Theophilus SC, Shariffudin A, Abdullah JM
    Malays J Med Sci, 2015 Dec;22(Spec Issue):62-71.
    PMID: 27006639 MyJurnal
    Mortality and morbidity associated with intracerebral hemorrhage is still high. Up to now, there are no evidence-based effective treatments for acute ICH. This study is to assess the effect of tranexamic acid (TXA) on hematoma growth of patients with spontaneous ICH compared to a placebo.
  2. Arumugam A, Tan SE, Tan SL, Tan JE, Hussin FH, Zenian MS, et al.
    Malays J Med Sci, 2023 Jun;30(3):93-102.
    PMID: 37425386 DOI: 10.21315/mjms2023.30.3.8
    BACKGROUND: Intracerebral haemorrhage (ICH) can be devastating, particularly if haematoma expansion occurs. The efficacy of tranexamic acid (TXA), an anti-fibrinolytic agent, in reducing haematoma expansion is now being studied worldwide. However, the optimal dosage of TXA has yet to be determined. This study was designed to further establish the potential of different doses of TXA.

    METHODS: A double-blinded, randomised, placebo-controlled study was carried out among adults with non-traumatic ICH. Eligible study subjects were randomly assigned to receive placebo, 2-g TXA treatment or 3-g TXA treatment. Haematoma volumes before and after intervention were measured using the planimetric method.

    RESULTS: A total of 60 subjects with 20 subjects in each treatment group were recruited for this study. Among the 60 subjects, the majority were male (n = 36, 60%), had known cases of hypertension (n = 43, 71.7%) and presented with full Glasgow coma scale (GCS) (n = 41, 68.3%). The results showed that there was no statistically significant difference (P = 0.315) in the mean changes of haematoma volume when compared with three study groups using ANCOVA, although the 3-g TXA group was the only group that showed haematoma volume reduction (mean reduction of 0.2 cm3) instead of expansion as in placebo (mean expansion 1.8 cm3) and 2-g TXA (mean expansion 0.3 cm3) groups. Good recovery was observed in all study groups, with only three subjects being moderately disabled. No adverse effects were reported in any of the study groups.

    CONCLUSION: To the best of our knowledge, this is the first clinical study using 3 g of TXA in the management of non-traumatic ICH. From our study, 3 g of TXA may potentially be helpful in reducing haematoma volume. Nonetheless, a larger-scale randomised controlled trial should be carried out to further establish the role of 3 g of TXA in non-traumatic ICH.

  3. Awang MS, Abdullah JM, Abdullah MR, Tahir A, Tharakan J, Prasad A, et al.
    Med Sci Monit, 2007 Jul;13(7):CR330-2.
    PMID: 17599028
    Nerve conduction study is essential in the diagnosis of focal neuropathies and diffuse polyneuropathies. There are many factors that can affect nerve conduction velocity, and age is one of them. Most of the many studies of this effect, and the values from them, were on Caucasian subjects. Therefore, this study was designed to investigate the effect of age on conduction velocity among healthy Asian Malay subjects by analyzing its influence on the median, ulnar, and sural nerves.
  4. Baharuddin WNA, Yusoff AAM, Abdullah JM, Osman ZF, Ahmad F
    Malays J Med Sci, 2018 Nov;25(6):22-27.
    PMID: 30914876 DOI: 10.21315/mjms2018.25.6.3
    Glioblastoma multiforme (GBM) is one of the most common primary brain tumours in adults, accounting for almost 65% of all cases. Among solid tumours, GBM is characterised by strong angiogenesis, including the highest degree of vascular proliferation and endothelial cell hyperplasia. Despite numerous improvements in existing treatment approaches, the prognosis of GBM patients remains poor, with a mean survival of only 14.6 months. Growing evidence has shown significant overexpression of the ephrin type-A receptor 2 (EphA2) receptor in various malignancies, including GBM, as well as a correlation to poor prognoses. It is believed that EphA2 receptors play important roles in mediating GBM tumourigenesis, including invasion, metastasis, and angiogenesis. Despite the clinical and pathological importance of tumour-associated vasculature, the underlying mechanism involving EphA2 is poorly known. Here, we have summarised the current knowledge in the field regarding EphA2 receptors' roles in the angiogenesis of GBM.
  5. Begum T, Reza F, Ahmed I, Abdullah JM
    J Integr Neurosci, 2014 Mar;13(1):71-88.
    PMID: 24738540 DOI: 10.1142/S0219635214500058
    Simple geometric and organic shapes and their arrangement are being used in different neuropsychology tests for the assessment of cognitive function, special memory and also for the therapy purpose in different patient groups. Until now there is no electrophysiological evidence of cognitive function determination for simple geometric, organic shapes and their arrangement. Then the main objective of this study is to know the cortical processing and amplitude, latency of visual induced N170 and P300 event related potential components on different geometric, organic shapes and their arrangement and different educational influence on it, which is worthwhile to know for the early and better treatment for those patient groups. While education influenced on cognitive function by using auditory oddball task, little is known about the influence of education on cognitive function induced by visual attention task in case of the choice of geometric, organic shapes and their arrangements. Using a 128-electrode sensor net, we studied the responses of the choice of the different geometric and organic shapes randomly in experiment 1 and their arrangements in experiment 2 in the high, medium and low education groups. In both experiments, subjects push the button "1" or "2" if like or dislike, respectively. Total 45 healthy subjects (15 in each group) were recruited. ERPs were measured from 11 electrode sites and analyzed to see the evoked N170/N240 and P300 ERP components. There were no differences between like and dislike in amplitudes even in latencies in every stimulus in both experiments. We fixed geometric shapes and organic shapes stimuli only, not like and dislike. Upon the stimulus types, N170 ERP component was found instead of N240, in occipito-temporal (T5, T6, O1 and O2) locations where the amplitude is the highest at O2 location and P300 was distributed in the central (Cz and Pz) locations in both experiments in all groups. In experiment 1, significant low amplitude and non-significant larger latency of the N170 component are found out at O1 location for both stimuli in low education group comparing medium education groups, but in experiment 2, there is no significant difference between stimuli among groups in amplitude and latency. In both experiments, P300 component was found in Cz and Pz locations though the amplitudes are higher at Cz than Pz areas. In experiment 1, medium education group evoked significantly (geometric shape stimuli, P = 0.05; organic shape stimuli, P = 0.02) higher amplitude of P300 component comparing low education group at Cz location. Whereas, there is no significant difference of amplitudes among groups across stimuli in Cz and Pz locations in experiment 2. Latencies have no significant differences in both experiments among groups also, but longer latency are found in low education group at Cz location comparing medium education group, though not significant. We conclude that simple geometric shapes, organic shapes and their arrangements evoked visual N170 component at temporo-occipital areas with right lateralization and P300 ERP component at centro-parietal areas. Significant low amplitude of N170 and P300 ERP components and longer latencies during different shape stimuli in low education group prove that, low education significantly influence on visual cognitive functions in low education group.
  6. Bhaskar S, Abdullah JM, Ghazali MM
    Neurosciences (Riyadh), 2008 Oct;13(4):356-8.
    PMID: 21063360
    OBJECTIVE: To look for any possible coexistence of CACNA1A, ATP1A2, and KCNN3 gene mutations in migraine patients who had human platelet HPA-1a/1b polymorphism, which is also known as PlA1/A2 polymorphism.
    METHODS: The study was carried out at the Neurology Clinic, Hospital University Sains Malaysia, Kelantan, Malaysia between April 2004 and March 2005. The DNA from 4 patients who had migraine with the HPA1a/1b polymorphism were analyzed by polymerase chain reaction using the allele specific oligonucleotide technique to detect the presence of CACNA1A, ATP1A2, and KCNN3 genotypes.
    RESULTS: We found that the CACNA1A gene mutation alone was present in only one patient who presented with classical migraine with aura. The gene mutations on ATP1A2 and KCNN3 were seen in none of our 4 cases with migraine.
    CONCLUSION: There is no coexistence between the platelet HPA-1a/1b polymorphism and the ATP1A2 and KCNN3 gene mutations, though one classical migraine patient with HPA-1a/1b polymorphism had the CACNA1A gene mutation. Larger studies are warranted to confirm these findings.
    Study site: Neurology Clinic, Hospital Universiti Sains Malaysia (HUSM), Kelantan, Malaysia
  7. Bhaskar S, Abdullah JM, Yusoff NM, Prasad A
    Singapore Med J, 2007 Jun;48(6):598-9.
    PMID: 17538770
  8. Binti Mohd Yusuf Yeo NA, Muthuraju S, Wong JH, Mohammed FR, Senik MH, Zhang J, et al.
    Brain Behav, 2018 09;8(9):e01093.
    PMID: 30105867 DOI: 10.1002/brb3.1093
    INTRODUCTION: Centella asiatica is an herbal plant that contains phytochemicals that are widely believed to have positive effects on cognitive function. The adolescent stage is a critical development period for the maturation of brain processes that encompass changes in physical and psychological systems. However, the effect of C. asiatica has not been extensively studied in adolescents. The aim of this study was therefore to investigate the effects of a C. asiatica extract on the enhancement of learning and memory in adolescent rats.

    METHODS: The locomotor activity, learning, and memory were assessed by using open field test and water T-maze test. This study also examined changes in neuronal cell morphology using cresyl violet and apoptosis staining. We also performed immunohistochemical study to analyse the expression of the glutamate AMPA receptor (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) GluA1 subunit and the GABA receptor (γ-Aminobutyric Acid) subtype GABAA α1 subunit in the hippocampus of the same animals.

    RESULTS: We found no significant changes in locomotor activity (p > 0.05). The water T-maze data showed that 30 mg/kg dose significantly (p  0.05). Histological data revealed no neuronal morphological changes. Immunohistochemical analysis revealed increased expression of the AMPA GluA1 receptor subunit but there was no effect on GABAA receptor α1 subunit expression in the CA1 and CA2 subregions of the hippocampus.

    CONCLUSIONS: The C. asiatica extract therefore improved hippocampus-dependent spatial learning and memory in a dose-dependent manner in rats through the GluA1-containing AMPA receptor in the CA1 and CA2 sub regions of the hippocampus.

  9. Chai WJ, Abd Hamid AI, Abdullah JM
    Front Psychol, 2018;9:401.
    PMID: 29636715 DOI: 10.3389/fpsyg.2018.00401
    Since the concept of working memory was introduced over 50 years ago, different schools of thought have offered different definitions for working memory based on the various cognitive domains that it encompasses. The general consensus regarding working memory supports the idea that working memory is extensively involved in goal-directed behaviors in which information must be retained and manipulated to ensure successful task execution. Before the emergence of other competing models, the concept of working memory was described by the multicomponent working memory model proposed by Baddeley and Hitch. In the present article, the authors provide an overview of several working memory-relevant studies in order to harmonize the findings of working memory from the neurosciences and psychological standpoints, especially after citing evidence from past studies of healthy, aging, diseased, and/or lesioned brains. In particular, the theoretical framework behind working memory, in which the related domains that are considered to play a part in different frameworks (such as memory's capacity limit and temporary storage) are presented and discussed. From the neuroscience perspective, it has been established that working memory activates the fronto-parietal brain regions, including the prefrontal, cingulate, and parietal cortices. Recent studies have subsequently implicated the roles of subcortical regions (such as the midbrain and cerebellum) in working memory. Aging also appears to have modulatory effects on working memory; age interactions with emotion, caffeine and hormones appear to affect working memory performances at the neurobiological level. Moreover, working memory deficits are apparent in older individuals, who are susceptible to cognitive deterioration. Another younger population with working memory impairment consists of those with mental, developmental, and/or neurological disorders such as major depressive disorder and others. A less coherent and organized neural pattern has been consistently reported in these disadvantaged groups. Working memory of patients with traumatic brain injury was similarly affected and shown to have unusual neural activity (hyper- or hypoactivation) as a general observation. Decoding the underlying neural mechanisms of working memory helps support the current theoretical understandings concerning working memory, and at the same time provides insights into rehabilitation programs that target working memory impairments from neurophysiological or psychological aspects.
  10. Chan HC, Aasim WA, Abdullah NM, Naing NN, Abdullah JM, Saffari MH, et al.
    Singapore Med J, 2005 May;46(5):219-23.
    PMID: 15858690
    Paediatric minor head injuries (MHI) are just as common in both bigger and smaller towns in Malaysia. Urban-based MHI are due more to motor vehicular injuries compared to rural-based MHI which are mainly due to non-motor vehicular injuries. The main objectives of this study were to compare incidence of admitted patients to accident and emergency departments of hospitals in two different settings in Malaysia, namely: Ipoh (urban-based) and Kota Bharu (rural-based); and to correlate to demographical characteristics, types of accident, clinical signs and symptoms, radiological and computed tomography (CT) findings, management; and finally, to determine clinical predictors of intracranial injury in MHI.
  11. Chen XW, Shafei MN, Abdullah JM, Musa KI
    Neuroepidemiology, 2019;52(3-4):214-219.
    PMID: 30799411 DOI: 10.1159/000497238
    BACKGROUND: A comprehensive evaluation of interrater reliability is crucial when it comes to multiple coders assessing the stroke outcomes using telephone interview. The reliability between telephone raters is important, as it could affect the accuracy of the findings published.

    OBJECTIVE: This study aimed to establish the interrater reliability between multiple telephone interviewers when assessing long-term stroke outcomes.

    METHODS: Patients alive at discharge selected in a retrospective cohort stroke project were recruited in this study. Their contact numbers were obtained from the medical record unit. The patients and/or proxies were interviewed based on a standardized script in Malay or English. Stroke outcomes assessed were modified Rankin Scale (mRS) and Barthel Index (BI) at 1-year post discharge. Fully crossed design was applied and 3 assessors collected the data simultaneously. Data was analysed using the software R version 3.4.4.

    RESULTS: Out of 207 subjects recruited, 132 stroke survivors at the time of interview were analysed. We found a significant excellent interrater reliability between telephone interviewers assessing BI, with intraclass correlation coefficient at 0.996 (95% CI 0.995-0.997). Whereas substantial agreement between the telephone interviewers was revealed in assessing mRS, with Fleiss', Conger's and Light's Kappa statistics reporting 0.719 and the Nelson's model-based κm kappa statistic reporting 0.689 (95% CI 0.667-0.711).

    CONCLUSION: It is reliable to get multiple raters in assessing mRS and BI using the telephone system. It is worthwhile to make use of a telephone interview to update clinicians on their acute clinical management towards long-term stroke prognosis.

  12. Chih AN, Hieng AW, Rahman NA, Abdullah JM
    Malays J Med Sci, 2017 Mar;24(1):21-30.
    PMID: 28381926 DOI: 10.21315/mjms2017.24.1.3
    INTRODUCTION: Symptomatic chronic subdural hematomas (CSDH) remain one of the most frequent diagnoses in current neurosurgical practice. Burr-hole craniostomy with irrigation and placement of close-system drainage is the current recommended surgery for symptomatic CSDH. The aim of this study is to perform a direct comparison between two surgical techniques in the treatment of symptomatic CSDH, which have been proven in previous studies to be efficient. Our main objective was to compare the efficacy of placement of a subperiosteal drain (SPD) and a subdural drain (SDD) following single burr-hole craniostomy and irrigation, and to demonstrate any significant differences in terms of overall surgical complications, functional outcome at three months and mortality rate.

    MATERIALS AND METHODS: The study was carried out in two local neurosurgical centres. The SPD group was performed in Hospital Umum Sarawak (HUS) and the SDD group was performed in Hospital Sultanah Aminah Johor Bahru (HSAJB), from 1 January 2012 till 30 January 2014 with a total of 30 patients in both treatment groups.

    RESULTS: Overall, there were no statistically significant difference in terms of patient general characteristics, pre-operative and post-operative symptoms, Markwalder grades, post-operative hematoma volume and recurrence, mortality and functional outcome at discharge and at three month follow-up between both groups. Albeit not achieving statistical significance, we observed a lower rate of surgical complication especially for post-operative intracranial hematoma with placement of the SPD system.

    CONCLUSIONS: Our study concludes that both treatment methods proved to be highly effective in the treatment of CSDH. However, with a lower overall surgical complication rate, treatment with single burr-hole craniostomy, irrigation and placement of the SPD system can be considered a treatment of choice for the management of symptomatic CSDH.

  13. Chin TY, Kiat SS, Faizul HG, Wu W, Abdullah JM
    Malays J Med Sci, 2017 Mar;24(1):31-39.
    PMID: 28381927 MyJurnal DOI: 10.21315/mjms2017.24.1.4
    BACKGROUND: The neuroprotective role of minocycline in the treatment of brachial plexus injury is controversial.

    OBJECTIVE: To study the neuroprotective effect of minocycline via different routes in adult Sprague Dawley rats with brachial plexus injury.

    METHODS: The C7 nerve roots of the animals were avulsed via an anterior extravertebral approach. Traction force was used to transect the ventral motor nerve roots at the preganglionic level. Intraperitoneal and intrathecal minocycline (50 mg/kg for the first week and 25 mg/kg for the second week) were administered to promote motor healing. The spinal cord was harvested six weeks after the injury, and structural changes following the avulsion injury and pharmacological intervention were analysed.

    RESULTS: Motor neuron death and microglial proliferation were observed after the administration of minocycline via two different routes (intraperitoneal and intrathecal) following traumatic avulsion injury of the ventral nerve root. The administration of intraperitoneal minocycline reduced the microglia count but increased the motor neuron count. Intrathecal minocycline also reduced the microglial count, with a greater reduction than in the intraperitoneal group, but it decreased the motor neuron count.

    CONCLUSIONS: Intraperitoneal minocycline increased motor neuron survival by inhibiting microglial proliferation following traumatic avulsion injury of the nerve root. The inhibitory effect was augmented by the use of intrathecal minocycline, in which the targeted drug delivery method increased the bioavailability of the therapeutic agent. However, motor neuron survival was impaired at a higher concentration of minocycline via the intrathecal route due to the more efficient method of drug delivery. Microglial suppression via minocycline can have both beneficial and damaging effects, with a moderate dose being beneficial as regards motor neuron survival but a higher dose proving neurotoxic due to impairment of the glial response and Wallerian degeneration, which is a pre-requisite for regeneration.

  14. Chockalingam K, A Rahman NA, Idris Z, Theophilus SC, Abdullah JM, Ghani ARI, et al.
    Malays J Med Sci, 2023 Aug;30(4):71-84.
    PMID: 37655152 DOI: 10.21315/mjms2023.30.4.7
    BACKGROUND: Traumatic brain injury (TBI) is the third leading cause of death and disability worldwide in 2020. For patients with TBI with significant intracranial bleeds, urgent surgical intervention remains the mainstay treatment. This study aims to evaluate the time to definite surgical intervention since admission and its association with patient outcomes in a neurosurgery referral centre in Malaysia.

    METHODS: This retrospective study was conducted at Hospital Sultanah Aminah Johor Bahru from 1 January 2019 to 31 December 2019. All patients with TBI requiring urgent craniotomy were identified from the operating theatre registry, and the required data were extracted from their clinical notes, including the Glasgow Outcome Score (GCS) at discharge and 6 months later. Logistic regression was performed to identify the factors associated with poor outcomes.

    RESULTS: A total of 154 patients were included in this study. The median door-to-skin time was 605 (interquartile range = 494-766) min. At discharge, 105 patients (68.2%) had poor outcomes. At the 6-month follow-up, only 58 patients (37.7%) remained to have poor outcomes. Simple logistic regression showed that polytrauma, hypotensive episode, ventilation, severe TBI, and the door-to-skin time were significantly associated with poor outcomes. After adjustments for the clinical characteristics in the analysis, the likelihood of having poor outcomes for every minute delay in the door-to-skin time increased at discharge (adjusted odds ratio [AOR] = 1.005; 95% confidence interval [CI] = 1.002-1.008) and the 6-month follow-up (AOR = 1.008; 95% CI = 1.005-1.011).

    CONCLUSION: The door-to-skin time is directly proportional to poor outcomes in patients with TBI. Concerted efforts from all parties involved in trauma care are essential in eliminating delays in surgical interventions and improving outcomes.

  15. Chong PN, Sangu M, Huat TJ, Reza F, Begum T, Yusoff AAM, et al.
    Malays J Med Sci, 2018 Nov;25(6):28-45.
    PMID: 30914877 MyJurnal DOI: 10.21315/mjms2018.25.6.4
    Background: Following brain injury, development of hippocampal sclerosis often led to the temporal lobe epilepsy which is sometimes resistant to common anti-epileptic drugs. Cellular and molecular changes underlying epileptogenesis in animal models were studied, however, the underlying mechanisms of kainic acid (KA) mediated neuronal damage in rat hippocampal neuron cell culture alone has not been elucidated yet.

    Methods: Embryonic day 18 (E-18) rat hippocampus neurons were cultured with poly-L-lysine coated glass coverslips. Following optimisation, KA (0.5 μM), a chemoconvulsant agent, was administered at three different time-points (30, 60 and 90 min) to induce seizure in rat hippocampal neuronal cell culture. We examined cell viability, neurite outgrowth density and immunoreactivity of the hippocampus neuron culture by measuring brain derived neurotrophic factor (BDNF), γ-amino butyric acid A (GABAA) subunit α-1 (GABRA1), tyrosine receptor kinase B (TrkB), and inositol trisphosphate receptor (IP3R/IP3) levels.

    Results: The results revealed significantly decreased and increased immunoreactivity changes in TrkB (a BDNF receptor) and IP3R, respectively, at 60 min time point.

    Conclusion: The current findings suggest that TrkB and IP3 could have a neuroprotective role which could be a potential pharmacological target for anti-epilepsy drugs.

  16. Chuang HG, Aziz NHA, Wong JH, Mustapha M, Abdullah JM, Idris Z, et al.
    Eur Neuropsychopharmacol, 2021 04;45:59-72.
    PMID: 32014377 DOI: 10.1016/j.euroneuro.2019.12.121
    The present study focused on investigating the effect of toll-like receptor 4 (TLR4) antagonist Lipopolysaccharide-Rhodobacter sphaeroides(LPS-RS) on acute, stress-induced voluntary ethanol preference and drinking behaviour, neuronal components activation, and gene expression associated with stress and addictive behaviour. This study involved the exposure of restraint stress and social isolation using Swiss Albino mice. Two-bottle choice ethanol preference analysis was used in the evaluation of voluntary ethanol seeking and drinking behaviour. Several behavioural assessments were carried out to assess fear and anxiety-like behaviour, neuromuscular ability, motor coordination and locomotion. Morphological and immunoreactivity analysis and gene expression analysis were done after the completion of behavioural assessments. TLR4 antagonist LPS-RS treated stressed-mice showed a significant decrease in ethanol drinking compared with stressed mice. Behavioural results showed that stress exposure induced fear and anxiety-like behaviour; however; no significant deficit was found on motor coordination, neuromuscular ability, locomotion and exploratory behaviour among groups. Morphological analysis showed no significant change in the prefrontal cortex and hippocampus among all groups, while immunoreactivity analysis showed higher expression of c-Fos in prefrontal cortex and hippocampus, higher TLR4 expression in the prefrontal cortex and glial fibrillary acidic protein (GFAP) in hippocampus among stressed-animals. Stressed-mice also showed significant increase in TLR4, Nuclear Factor-Kappa B (NF-kB), inducible nitric oxide synthase (iNOS), dopamine receptor D2 (DRD2), cyclic adenosine monophosphate (cAMP) response element binding protein-1 (CREB-1) and opioid receptor MU-1 (OPRM-1) genes expression compared with control and LPS-RS treated stressed-mice. As a conclusion, the antagonism of TLR4 could provide therapeutic value in the treatment of stress-induced addiction.
  17. Das S, Palaniandy K, Abu Bakar A, Idris Z, Abdullah JM
    Cureus, 2020 Feb 03;12(2):e6850.
    PMID: 32181085 DOI: 10.7759/cureus.6850
    Cervical spine injuries are rare occurrences in children, especially the congenital anomalies of the atlas vertebra. Any injury involving the craniovertebral junction such as Jefferson fracture, is a valid cause for alarm due to the complex nature of the craniovertebral junction and the morbidity associated with it. We report the case of a 10-year-old male, who had failure of fusion of anterior arch of atlas due to the failure of formation of the anterior midline synchondrosis, and this mimicked a Jefferson fracture. If it was not for the peculiar absence of any corresponding evidence to suggest spinal injury, we might have mistaken this extremely rare but benign anomaly for a Jefferson fracture and subjected the patient to needless surgical treatment. Hence, it is concluded that keen clinical acumen and clear understanding of the developmental anatomy of these patients may be necessary to adequately manage them.
  18. Elaina NS, Malik AS, Shams WK, Badruddin N, Abdullah JM, Reza MF
    Clin Neuroradiol, 2018 Jun;28(2):267-281.
    PMID: 28116447 DOI: 10.1007/s00062-017-0557-0
    PURPOSE: To localize sensorimotor cortical activation in 10 patients with frontoparietal tumors using quantitative magnetoencephalography (MEG) with noise-normalized approaches.

    MATERIAL AND METHODS: Somatosensory evoked magnetic fields (SEFs) were elicited in 10 patients with somatosensory tumors and in 10 control participants using electrical stimulation of the median nerve via the right and left wrists. We localized the N20m component of the SEFs using dynamic statistical parametric mapping (dSPM) and standardized low-resolution brain electromagnetic tomography (sLORETA) combined with 3D magnetic resonance imaging (MRI). The obtained coordinates were compared between groups. Finally, we statistically evaluated the N20m parameters across hemispheres using non-parametric statistical tests.

    RESULTS: The N20m sources were accurately localized to Brodmann area 3b in all members of the control group and in seven of the patients; however, the sources were shifted in three patients relative to locations outside the primary somatosensory cortex (SI). Compared with the affected (tumor) hemispheres in the patient group, N20m amplitudes and the strengths of the current sources were significantly lower in the unaffected hemispheres and in both hemispheres of the control group. These results were consistent for both dSPM and sLORETA approaches.

    CONCLUSION: Tumors in the sensorimotor cortex lead to cortical functional reorganization and an increase in N20m amplitude and current-source strengths. Noise-normalized approaches for MEG analysis that are integrated with MRI show accurate and reliable localization of sensorimotor function.

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