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Addition of zygomatic arch resection in decompressive craniectomy

Martin AG, Abdullah JY, Jaafar A, Ghani AR, Rajion ZA, Abdullah JM

J Clin Neurosci, 2015 Apr;22(4):735-9.
PMID: 25564264 DOI: 10.1016/j.jocn.2014.09.021

Decompressive craniectomy (DC) is a surgical option in managing uncontrolled raised intracranial pressure refractory to medical therapy. The authors evaluate the addition of zygomatic arch (ZA) resection with standard DC and analyze the resulting increase in brain volume using three-dimensional volumetric CT scans. Measurements of brain expansion dimension morphometrics from CT images were also analyzed. Eighteen patients were selected and underwent DC with ZA resection. The pre- and post-operative CT images were analyzed for volume and dimensional changes. CT images of 29 patients previously operated on at the same center were retrieved from the picture archiving and communication system (PACS) and were similarly studied. The findings obtained from the two groups were compared and analyzed. Analysis from three-dimensional CT volumetric techniques revealed an significant increase of 27.97ml (95% confidence interval [CI]: 39.98-180.36; p=0.048) when compared with standard DC. Brain expansion analysis of maximum hemicraniectomy diameter revealed a mean difference of 0.82cm (95% CI: 0.25-1.38; p=0.006). Analysis of the ratio of maximum hemicraniectomy diameter to maximum anteroposterior diameter gave a mean difference of 0.04 (95% CI: 0.05-0.07; p=0.026). The addition of ZA resection to standard DC may prove valuable in terms of absolute brain volume gain. This technique is comparable to other maneuvers used to provide maximum brain expansion in the immediate post-operative period.
Intracerebral haematomas after deep brain stimulation surgery in a patient with Tourette syndrome and low factor XIIIA activity

Idris Z, Ghani AR, Mar W, Bhaskar S, Wan Hassan WN, Tharakan J, et al.

J Clin Neurosci, 2010 Oct;17(10):1343-4.
PMID: 20620064 DOI: 10.1016/j.jocn.2010.01.054

A 24-year-old male patient with refractory Tourette syndrome was treated with deep brain stimulation (DBS) and developed subsequent bilateral subcortical haematomas. Additional blood tests revealed abnormalities of plasma factor XIIIA and tryptophan levels, which may be associated with Tourette syndrome. Neurosurgeons who perform DBS surgery on patients with Tourette syndrome must be aware of possible disastrous complications resulting from factor XIIIA disorders of blood haemostasis. Routine screening for this condition is not typically performed prior to surgery in these patients.
Two surgical methods used in 90 patients with intracranial subdural empyema

Mat Nayan SA, Mohd Haspani MS, Abd Latiff AZ, Abdullah JM, Abdullah S

J Clin Neurosci, 2009 Dec;16(12):1567-71.
PMID: 19793660 DOI: 10.1016/j.jocn.2009.01.036

We studied the efficacy of two surgical methods used for the treatment of intracranial subdural empyema (ISDE) at our centre. A cross-sectional study (1999-2005) of 90 patients with non-traumatic supratentorial ISDE revealed that the two surgical methods used for empyema removal were burr hole/s and drainage (50 patients, 55.6%) and a cranial bone opening procedure (CBOP) (40 patients, 44.4%). Patients in the CBOP group had a better result in terms of clinical improvement (chi-squared analysis, p=0.006) and clearance of empyema on brain CT scan (chi-squared analysis, p<0.001). Reoperation was more frequent among patients who had undergone burr hole surgery (multiple logistic regression, p<0.001). The outcome and morbidity of ISDE survivors were not related to the surgical method used (p>0.05). The only factor that significantly affected the morbidity of ISDE was level of consciousness at the time of surgery (multiple logistic regression, p<0.001). We conclude that CBOP and evacuation of the empyema is a better surgical method for ISDE than burr hole/s and drainage. Wide cranial opening and empyema evacuation improves neurological status, gives better clearance of the empyema and reduces the need for reoperation. Level of consciousness at the time of presentation is a predictor of the morbidity of ISDE. Thus, aggressive surgical treatment should occur as early as possible, before the patient deteriorates.
History of neurosciences at the School of Medical Sciences, Universiti Sains Malaysia

Idris B, Sayuti S, Abdullah JM

J Clin Neurosci, 2007 Feb;14(2):148-52.
PMID: 17161289

Universiti Sains Malaysia is the only institution in Malaysia which incorporates all fields of the neurosciences under one roof. The integration of basic and clinical neurosciences has made it possible for this institution to become an excellent academic and research centre. This article describes the history, academic contributions and scientific progress of neurosciences at Universiti Sains Malaysia.
Influence of education level on design-induced N170 and P300 components of event related potentials in the human brain

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.
Decoding of visual information from human brain activity: A review of fMRI and EEG studies

Zafar R, Malik AS, Kamel N, Dass SC, Abdullah JM, Reza F, et al.

J Integr Neurosci, 2015 Jun;14(2):155-68.
PMID: 25939499 DOI: 10.1142/S0219635215500089

Brain is the command center for the body and contains a lot of information which can be extracted by using different non-invasive techniques. Electroencephalography (EEG), Magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) are the most common neuroimaging techniques to elicit brain behavior. By using these techniques different activity patterns can be measured within the brain to decode the content of mental processes especially the visual and auditory content. This paper discusses the models and imaging techniques used in visual decoding to investigate the different conditions of brain along with recent advancements in brain decoding. This paper concludes that it's not possible to extract all the information from the brain, however careful experimentation, interpretation and powerful statistical tools can be used with the neuroimaging techniques for better results.
Fulltext Acute application of Centella asiatica extract enhanced AMPAR-mediated postsynaptic currents in rat entorhinal cortex

Wong JH, Reza F, Muthuraju S, Chuang HG, Zhang J, Senik MH, et al.

J Integr Neurosci, 2020 Jun 30;19(2):217-227.
PMID: 32706186 DOI: 10.31083/j.jin.2020.02.50

Centella asiatica is notable for its wide range of biological activities beneficial to human health, particularly its cognitive enhancement and neuroprotective effects. The α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors are ionotropic glutamate receptors mediating fast excitatory neurotransmission essential in long-term potentiation widely thought to be the cellular mechanism of learning and memory. The method of whole-cell patch-clamp was used to study the effect of the acute application of Centella asiatica extract on the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor-mediated spontaneous excitatory postsynaptic currents in the entorhinal cortex of rat brain slices. The respective low dose of test compounds significantly increased the amplitude of spontaneous excitatory postsynaptic currents while having no significant effects on the frequency. The findings suggested that Centella asiatica extract increased the response of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors at the postsynaptic level, revealing the potential role of Centella asiatica in modulating the glutamatergic responses in the entorhinal cortex of rat brain slices to produce cognitive enhancement effects.
Decoding of visual activity patterns from fMRI responses using multivariate pattern analyses and convolutional neural network

Zafar R, Kamel N, Naufal M, Malik AS, Dass SC, Ahmad RF, et al.

J Integr Neurosci, 2017;16(3):275-289.
PMID: 28891512 DOI: 10.3233/JIN-170016

Decoding of human brain activity has always been a primary goal in neuroscience especially with functional magnetic resonance imaging (fMRI) data. In recent years, Convolutional neural network (CNN) has become a popular method for the extraction of features due to its higher accuracy, however it needs a lot of computation and training data. In this study, an algorithm is developed using Multivariate pattern analysis (MVPA) and modified CNN to decode the behavior of brain for different images with limited data set. Selection of significant features is an important part of fMRI data analysis, since it reduces the computational burden and improves the prediction performance; significant features are selected using t-test. MVPA uses machine learning algorithms to classify different brain states and helps in prediction during the task. General linear model (GLM) is used to find the unknown parameters of every individual voxel and the classification is done using multi-class support vector machine (SVM). MVPA-CNN based proposed algorithm is compared with region of interest (ROI) based method and MVPA based estimated values. The proposed method showed better overall accuracy (68.6%) compared to ROI (61.88%) and estimation values (64.17%).
Fulltext Combined use of maxillomandibular swing approach and neurosurgical ultrasonic aspirator in the management of extensive clival chordoma: a case report

Hassan S, Abdullah JM, Wan Din SJ, Idris Z

J Med Case Rep, 2008;2:49.
PMID: 18279530 DOI: 10.1186/1752-1947-2-49

Chordoma is a rare malignant tumour with an incidence of metastasis of less than 10 percent. Usually arising from clivus its posterior extension may involve the brainstem before presenting as nasal mass and obstruction. Surgery is the main mode of treatment with adjuvant radiotherapy. However surgery is rarely possible for a large intracranial lesion.
A preliminary study of using active vision guided robotic arm for bone drilling in a developing country

Abdullah MZ, Awang MS, Tan YC, Abdullah JM

J Neurol Surg A Cent Eur Neurosurg, 2014 Mar;75(2):155-7.
PMID: 23636911 DOI: 10.1055/s-0032-1330954

The study assesses the capability and accuracy of a robotic arm to perform burr holes.
Transfrontal Transaqueductal, Transtrigonal, and Suboccipital Infratentorial Supracerebellar Endoscopic Fenestration of Posterior Fossa Arachnoid Cysts: Three Surgical Cases

Idris Z, Tan YC, Kandasamy R, Ghani RI, Abdullah JM

J Neurol Surg A Cent Eur Neurosurg, 2017 Mar;78(2):210-215.
PMID: 26968147 DOI: 10.1055/s-0035-1571161

Symptomatic intracranial arachnoid cysts are commonly treated using neuroendoscopy. Cysts located within the posterior fossa may present a greater surgical challenge to the neurosurgeon due to the numerous vital neurovascular structures located within this confined space. Adding neuronavigation during endoscopy helps a neurosurgeon to visualize and utilize both anterior and posterior corridors safely to access and manage these lesions. We present three symptomatic posterior fossa arachnoid cysts that were treated successfully using minimally invasive neuronavigation-guided endoscopic neurosurgery utilizing the anterior transfrontal transaqueductal, anterior transfrontal transtrigonal, and posterior suboccipital infratentorial supracerebellar approaches.
Removal of BCG artefact from concurrent fMRI-EEG recordings based on EMD and PCA

Javed E, Faye I, Malik AS, Abdullah JM

J Neurosci Methods, 2017 11 01;291:150-165.
PMID: 28842191 DOI: 10.1016/j.jneumeth.2017.08.020

BACKGROUND: Simultaneous electroencephalography (EEG) and functional magnetic resonance image (fMRI) acquisitions provide better insight into brain dynamics. Some artefacts due to simultaneous acquisition pose a threat to the quality of the data. One such problematic artefact is the ballistocardiogram (BCG) artefact.
METHODS: We developed a hybrid algorithm that combines features of empirical mode decomposition (EMD) with principal component analysis (PCA) to reduce the BCG artefact. The algorithm does not require extra electrocardiogram (ECG) or electrooculogram (EOG) recordings to extract the BCG artefact.
RESULTS: The method was tested with both simulated and real EEG data of 11 participants. From the simulated data, the similarity index between the extracted BCG and the simulated BCG showed the effectiveness of the proposed method in BCG removal. On the other hand, real data were recorded with two conditions, i.e. resting state (eyes closed dataset) and task influenced (event-related potentials (ERPs) dataset). Using qualitative (visual inspection) and quantitative (similarity index, improved normalized power spectrum (INPS) ratio, power spectrum, sample entropy (SE)) evaluation parameters, the assessment results showed that the proposed method can efficiently reduce the BCG artefact while preserving the neuronal signals.
COMPARISON WITH EXISTING METHODS: Compared with conventional methods, namely, average artefact subtraction (AAS), optimal basis set (OBS) and combined independent component analysis and principal component analysis (ICA-PCA), the statistical analyses of the results showed that the proposed method has better performance, and the differences were significant for all quantitative parameters except for the power and sample entropy.
CONCLUSIONS: The proposed method does not require any reference signal, prior information or assumption to extract the BCG artefact. It will be very useful in circumstances where the reference signal is not available.
Fulltext Pleomorphic xanthoastrocytoma in a case of tuberous sclerosis

Martin AG, Singh MS, Idris B, Abdullah JM

J Neurosci Rural Pract, 2014 Jul;5(3):258-60.
PMID: 25002765 DOI: 10.4103/0976-3147.133580

Tuberous sclerosis is a known phakomatosis and the associated finding of a subependymal giant cell astrocytoma is common with this disorder. A case of tuberous sclerosis with a finding not previously reported, i.e. that of a pleomorphic xanthoastrocytoma, is presented here.
Endoscopic fenestration at the splenial-habenular junctional area for symptomatic cavum and tumor at the foramen of Monro: case reports and anatomical review

Idris Z, Johnson JR, Abdullah JM

J. Neurosurg., 2015 Mar;122(3):504-10.
PMID: 25343181 DOI: 10.3171/2014.9.JNS132683

The splenial-habenular junctional area is an alternative site for neuroendoscopic fenestration to divert CSF flow into the quadrigeminal cistern in cases in which endoscopic third ventriculostomy is not amenable. In some patients with obstructive hydrocephalus, the splenium of the corpus callosum can be elevated from the habenular complex. This exposes the membranous connection between the splenium and habenula, which can be fenestrated to divert the CSF flow into the quadrigeminal cistern. This technique can be performed in patients in whom the foramen of Monro or the third ventricle is blocked by a lesion. Here, the authors present 3 complex cases that were managed by neuronavigation-guided transventricular transcavum endoscopic fenestration of the splenial-habenular junctional area. These cases may increase the knowledge and understanding of the anatomy of this region.
Prediction of outcomes in traumatic brain injury: The IMPACT and CRASH prognostic models in a single neurosurgical center, Malaysia

Abdullah JM, Idris Z, Ghani AR, Lim MS

J Neurosurg Sci, 2023 Jun;67(3):367-373.
PMID: 33709663 DOI: 10.23736/S0390-5616.21.05249-8

BACKGROUND: Traumatic brain injury (TBI) has recently become a major concern for public health care and a socioeconomic burden internationally. Prognostic models are mathematical models developed from specific populations which are used to predict the mortality and unfavorable outcomes especially in trauma centers. Hence, we formulate a study to perform an external validation of the IMPACT and CRASH prognostic models; the CRASH model to predict 14-day mortality and 6-month unfavorable outcome and the IMPACT model to estimate 6-month mortality and unfavorable outcome in a single center cohort of TBI patients in Malaysia.
METHODS: All patients with traumatic brain injury (mild, moderate, and severe) who were admitted to Queen Elizabeth Hospital from November 1, 2017, to January 31, 2019, were prospectively analyzed through a data collection sheet. The discriminatory power of the models was assessed as area under the receiver operating characteristic curve and calibration was assessed using the Hosmer-Lemeshow (H-L) goodness-of-fit test and Cox calibration regression analysis.
RESULTS: We analyzed 281 patients with significant TBI treated in a single neurosurgical center in Malaysia over a 2-year period. The overall observed 14-day mortality was 9.6%, a 6-month unfavorable outcome of 23.5%, and a 6-month mortality of 13.2%. Overall, both the CRASH and IMPACT models showed good discrimination with AUCs ranging from 0.88 to 0.94 and both models calibrating satisfactorily H-L GoF P>0.05 and calibration slopes >1.0 although IMPACT seemed to be slightly more superior compared to the CRASH model.
CONCLUSIONS: The CRASH and IMPACT prognostic models displayed satisfactory overall performance in our cohort of TBI patients, but further investigations on factors contributing to TBI outcomes and continuous updating on both models remain crucial.
A Study of 309 Patients and at One Year Follow-Up for Depression after Traumatic Brain Injury

Looi MC, Idris Z, Kumaran T, Thyagarajan D, Abdullah JM, Ghani ARI, et al.

J Neurotrauma, 2023 Jan;40(1-2):94-101.
PMID: 36017631 DOI: 10.1089/neu.2022.0031

Traumatic brain injury (TBI) is one the major causes of death and morbidity in developing countries, where depression is a common psychiatric condition among individuals with TBI. The objectives were to investigate the occurrence and severity of depression one-year post-TBI; the association between radiological findings and depression; and the risk factors. We report a cross-sectional study among adult patients who were hospitalized because of TBI in the past one year. A structured data collection form was used to collect patients' demographic data during TBI, while the Patient Health Questionnaire (PHQ)-9 questionnaire was administered to assess the level of depression at one-year post-TBI. Of the 309 patients in this study; 46.6%, 26.2%, and 27.2% had mild, moderate, and severe TBI, respectively. The overall rate of depression was 33.7%, where 22.3%, 8.7%, and 2.6% had mild, moderate, and moderately severe depression, respectively. There was a significant, positive correlation between severity of TBI and level of depression; rs (0.427), p
Fulltext Generalized epilepsy with febrile seizure plus (GEFS+) spectrum: Novel de novo mutation of SCN1A detected in a Malaysian patient

Tan EH, Yusoff AA, Abdullah JM, Razak SA

J Pediatr Neurosci, 2012 May;7(2):123-5.
PMID: 23248692 DOI: 10.4103/1817-1745.102575

In this report, we describe a 15-year-old Malaysian male patient with a de novo SCN1A mutation who experienced prolonged febrile seizures after his first seizure at 6 months of age. This boy had generalized tonic clonic seizure (GTCS) which occurred with and without fever. Sequencing analysis of voltage-gated sodium channel a1-subunit gene, SCN1A, confirmed a homozygous A to G change at nucleotide 5197 (c.5197A > G) in exon 26 resulting in amino acid substitution of asparagines to aspartate at codon 1733 of sodium channel. The mutation identified in this patient is located in the pore-forming loop of SCN1A and this case report suggests missense mutation in pore-forming loop causes generalized epilepsy with febrile seizure plus (GEFS+) with clinically more severe neurologic phenotype including intellectual disabilities (mental retardation and autism features) and neuropsychiatric disease (anxiety disorder).
Blood-Brain Barrier Permeability of Asiaticoside, Madecassoside and Asiatic Acid in Porcine Brain Endothelial Cell Model

Hanapi NA, Mohamad Arshad AS, Abdullah JM, Tengku Muhammad TS, Yusof SR

J Pharm Sci, 2021 02;110(2):698-706.
PMID: 32949562 DOI: 10.1016/j.xphs.2020.09.015

Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10-6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases.
Fulltext Characterization and Cellular Internalization of Spherical Cellulose Nanocrystals (CNC) into Normal and Cancerous Fibroblasts

Shazali NAH, Zaidi NE, Ariffin H, Abdullah LC, Ghaemi F, Abdullah JM, et al.

Materials (Basel), 2019 Oct 04;12(19).
PMID: 31590332 DOI: 10.3390/ma12193251

The aim was to isolate cellulose nanocrystals (CNC) from commercialized oil palm empty fruit bunch cellulose nanofibre (CNF) through sulphuric acid hydrolysis and explore its safeness as a potential nanocarrier. Successful extraction of CNC was confirmed through a field emission scanning electron microscope (FESEM) and attenuated total reflection Fourier transmission infrared (ATR-FTIR) spectrometry analysis. For subsequent cellular uptake study, the spherical CNC was covalently tagged with fluorescein isothiocyanate (FITC), resulting in negative charged FITC-CNC nanospheres with a dispersity (Ð) of 0.371. MTT assay revealed low degree cytotoxicity for both CNC and FITC-CNC against C6 rat glioma and NIH3T3 normal fibroblasts up to 50 µg/mL. FITC conjugation had no contribution to the particle's toxicity. Through confocal laser scanning microscope (CLSM), synthesized FITC-CNC manifested negligible cellular accumulation, indicating a poor non-selective adsorptive endocytosis into studied cells. Overall, an untargeted CNC-based nanosphere with less cytotoxicity that posed poor selectivity against normal and cancerous cells was successfully synthesized. It can be considered safe and suitable to be developed into targeted nanocarrier.
Nerve conduction study of healthy Asian Malays: the influence of age on median, ulnar, and sural nerves

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.

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