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1.
Med J Malaysia ; 79(1): 102-110, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38287765

ABSTRACT

INTRODUCTION: Magnetic resonance spectroscopy (MRS) has an emerging role as a neuroimaging tool for the detection of biomarkers of Alzheimer's disease (AD). To date, MRS has been established as one of the diagnostic tools for various diseases such as breast cancer and fatty liver, as well as brain tumours. However, its utility in neurodegenerative diseases is still in the experimental stages. The potential role of the modality has not been fully explored, as there is diverse information regarding the aberrations in the brain metabolites caused by normal ageing versus neurodegenerative disorders. MATERIALS AND METHODS: A literature search was carried out to gather eligible studies from the following widely sourced electronic databases such as Scopus, PubMed and Google Scholar using the combination of the following keywords: AD, MRS, brain metabolites, deep learning (DL), machine learning (ML) and artificial intelligence (AI); having the aim of taking the readers through the advancements in the usage of MRS analysis and related AI applications for the detection of AD. RESULTS: We elaborate on the MRS data acquisition, processing, analysis, and interpretation techniques. Recommendation is made for MRS parameters that can obtain the best quality spectrum for fingerprinting the brain metabolomics composition in AD. Furthermore, we summarise ML and DL techniques that have been utilised to estimate the uncertainty in the machine-predicted metabolite content, as well as streamline the process of displaying results of metabolites derangement that occurs as part of ageing. CONCLUSION: MRS has a role as a non-invasive tool for the detection of brain metabolite biomarkers that indicate brain metabolic health, which can be integral in the management of AD.


Subject(s)
Alzheimer Disease , Humans , Alzheimer Disease/diagnostic imaging , Artificial Intelligence , Biomarkers , Brain/diagnostic imaging , Brain/pathology , Inflammation/metabolism , Inflammation/pathology , Magnetic Resonance Imaging/methods , Magnetic Resonance Spectroscopy/methods
2.
Med J Malaysia ; 76(5): 762-767, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34508392

ABSTRACT

Cardiac amyloidosis (CA) is a rare form of protein deposition disease, leading to restrictive cardiomyopathy that often presents with signs and symptoms of unexplained heart failure with preserved ejection fraction (HFpEF). There are two main subtypes of CA, namely light chain amyloidosis (AL) and transthyretin amyloidosis (ATTR), which are conventionally confirmed by endomyocardial biopsy (EMB). The prognosis and treatment of the subtypes differ extensively, making it crucial to distinguish between the two. Although echocardiography (ECHO) and cardiac magnetic resonance imaging (CMR) are useful to aid in the diagnosis, they are unable to differentiate between the subtypes. Advantageously, the transthyretin cardiac amyloidosis (ATTR-CA) subtype can be diagnosed based on nuclear medicine bone scintigraphy imaging using Technetiumlabelled bone-seeking radiotracers. We report a case of a previously well, elderly gentleman who presented with acute heart failure symptoms, whereby ECHO findings were suspicious for CA. Technetium-99m pyrophosphate (99mTc- PYP) bone scintigraphy performed with complementary single photon emission computed tomography/computed tomography (SPECT/CT) at three hours post-injection revealed radiotracer uptake in the myocardium that was higher than the skeletal bone uptake. This corresponded to Perugini score of 3 along with an increased heart to contralateral lung ratio (H:CL) of 1.69. The bone scintigraphy findings together with his symptoms, ECHO, CMR, and laboratory results enabled the diagnosis of ATTR-CA to be made. In summary, bone scintigraphy offers a reliable and non-invasive method for the diagnosis of ATTR-CA. We also highlight the diagnostic pitfalls and recommendations in reporting bone scintigraphy for the indication of typing cardiac amyloidosis.


Subject(s)
Amyloid Neuropathies, Familial , Cardiology , Heart Failure , Aged , Amyloid Neuropathies, Familial/diagnostic imaging , Diphosphates , Heart Failure/diagnostic imaging , Humans , Prealbumin , Radionuclide Imaging , Stroke Volume , Technetium
3.
Med J Malaysia ; 76(4): 451-453, 2021 07.
Article in English | MEDLINE | ID: mdl-34305103

ABSTRACT

Nuclear medicine (NM) has been established in Malaysia for almost 60 years. It is a specialty that utilizes radiopharmaceuticals for theranostics, by the assessment of bodily functions to diagnose certain diseases and conditions particularly in oncology, cardiology, and neurology as well as to provide therapeutic solutions in certain instances. The strengths of NM include the establishment of various nuclear medicine centres throughout the country, including in Sabah and Sarawak, particularly for general nuclear medicine, and the mushrooming of positron emission tomography computed tomography (PET/CT) centres along the states in the west coast of Malaysia, the institution of a formal national nuclear medicine physician training programme, and collaboration with international bodies to develop theranostic services. The challenges for NM ahead are namely regulatory and financial constraints for utilizing newer radiopharmaceuticals available in the international market, expansion of accredited training programmes to produce skilled healthcare workforce, optimization of resources at hand and multidisciplinary collaborations to reduce premature mortality of patients caused by noncommunicable diseases, particularly cancer.


Subject(s)
Nuclear Medicine , Physicians , Humans , Malaysia , Positron Emission Tomography Computed Tomography , Radionuclide Imaging
4.
Med J Malaysia ; 76(4): 510-517, 2021 07.
Article in English | MEDLINE | ID: mdl-34305112

ABSTRACT

BACKGROUND: Radioactive iodine 131I (RAI) therapy is one of the definitive treatments for paediatric differentiated thyroid cancer (DTC) initiated at nuclear medicine departments. In Malaysia, there is a need to identify the standardisation of treatment regimes to align with international standards. We aimed to evaluate the clinicopathological features and the patient response to RAI therapy among paediatric DTC cases at Hospital Kuala Lumpur (HKL), Malaysia. METHODS: A retrospective, longitudinal study was conducted among paediatric DTC patients treated with RAI in HKL and followed up between 2000-2016. Sixty-five patients were studied (mean period: 58.8±36 months). The clinicopathological data of the patients was recorded, and descriptive analysis was made. The association between categorical and continuous data with disease status was assessed using chi-square and Kruskal-Wallis tests, p-value <0.05 taken as statistically significant. RESULTS: Most patients were female (78.5%), and adolescents comprised 89.2%. Pre-pubertal age, those presenting with cervical nodal involvement, extra-thyroidal extension and lymphovascular invasion were significantly associated with distant metastases at presentation. There was no mortality reported during the follow-up period. Sixty per cent of patients achieved remission, while 40% had persistent disease. The persistent disease was significantly correlated with distant metastasis at presentation (p=0.025). CONCLUSIONS: Paediatric DTC manifests with a more extensive disease burden at presentation and requires multiple RAI doses. Despite this, it carries an excellent overall prognosis.


Subject(s)
Iodine Radioisotopes , Thyroid Neoplasms , Adolescent , Child , Female , Hospitals , Humans , Iodine Radioisotopes/therapeutic use , Longitudinal Studies , Malaysia , Male , Retrospective Studies , Thyroid Neoplasms/radiotherapy , Thyroid Neoplasms/surgery , Thyroidectomy , Treatment Outcome
5.
Med J Malaysia ; 76(3): 291-297, 2021 05.
Article in English | MEDLINE | ID: mdl-34031325

ABSTRACT

INTRODUCTION: Risk factors for cardiovascular disease (CVD) have been increasingly implicated in the development of dementia but little is known about the effects in a Malaysian population. We aimed to determine the interaction between sociodemographic and CVD risk factors among the dementia and mild cognitive impairment (MCI) patients in Malaysia. MATERIALS AND METHODS: A cross-sectional study was conducted in the memory clinic at Hospital Kuala Lumpur (HKL). Medical records data from 2014 to 2019 were extracted. Mini Mental State Examination (MMSE) test was used to assess the neurocognitive function of patients. RESULTS: A total of 298 patients (30 MCI, and 268 dementia) were evaluated, with dementia patients consisting of 78 Alzheimer's disease (AD), 93 Vascular dementia (VaD), 94 Mixed dementia, 2 early-onset Alzheimer's disease (EOAD) and 1 Logopenic Progressive Aphasia type of AD (LPA). MCI and dementia were significantly associated with a history of CVD, particularly stroke (p=0.023). CONCLUSION: Given that stroke significantly predicted the risk of developing vascular dementia among the patients in a central Malaysian population, lifestyle modifications are recommended to alleviate these risk factors of CVD.


Subject(s)
Alzheimer Disease , Cardiovascular Diseases , Alzheimer Disease/epidemiology , Alzheimer Disease/etiology , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/etiology , Cross-Sectional Studies , Heart Disease Risk Factors , Humans , Malaysia/epidemiology , Risk Factors
6.
Med J Malaysia ; 76(3): 401-413, 2021 05.
Article in English | MEDLINE | ID: mdl-34031341

ABSTRACT

INTRODUCTION: Internet Addiction Disorder (IAD) is an umbrella term for various types of Internet-based behavioural addiction, whereas Internet Gaming Disorder (IGD) addresses a specific type of IAD that is postulated to be due to a lack of control in impulse inhibition. IGD is an area of concern in the Diagnostic and Statistics Manual of Mental Disorders (DSM-5), which can be objectively assessed by dysfunctional behaviour and the increasing time of being online, particularly during the COVID-19 pandemic. Electroencephalography (EEG) identifies amplitude changes in the evoked response potential (ERP) among IGDs, correlated with underlying comorbidities. MATERIALS AND METHODS: A scoping review was performed to elaborate on the research regarding resting-state EEG and task-based EEG, particularly for Go/No-go paradigms pertaining to subjects with IAD or specifically IGD. The role of EEG was identified in its diagnostic capability to identify the salient changes that occurred in the response to reward network and the executive control network, using restingstate and task-based EEG. The implication of using EEG in monitoring the therapy for IAD and IGD was also reviewed. RESULTS: EEG generally revealed reduced beta waves and increased theta waves in addicts. IGD with depression demonstrated increased theta and decreased alpha waves. Whereas increased P300, a late cognitive ERP component, was frequently associated with impaired excessive allocation of attentional resources of the IAD towards addiction-specific cues. IGD had increased whole brain delta waves at baseline, which showed significant reduction post therapy. CONCLUSION: EEG can identify distinct neurophysiological changes among Internet Addiction Disorder and Internet Gaming Disorder that are akin to substance abuse disorders.


Subject(s)
Attention/physiology , Brain/physiopathology , Electroencephalography , Executive Function/physiology , Internet Addiction Disorder/physiopathology , Reward , Video Games , Adolescent , Humans , Screen Time
7.
Malays J Pathol ; 42(3): 423-431, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33361724

ABSTRACT

INTRODUCTION: Post-mortem computed tomography (PMCT) provides information that helps in the determination of the cause of death and corpse identification of disaster victims. One of the methods for corpse identification includes assessment of the body stature. There is a lack of post-mortem imaging studies that focus on the anthropometric assessment of corpses. Our aim was to identify the relationship between cadaveric spine length and autopsy length (AL) among and autopsy length (AL) among a Malaysian population and derive a regression formula for the estimation of corpse body height using PMCT. MATERIALS AND METHODS: We retrospectively assessed 107 cadavers that had undergone conventional autopsy and PMCT. We made 5 measurements from the PMCT that included cervical length (CL), thoracic length (TL), lumbosacral length (LS), total column length of the spine, excluding the sacrum and coccyx (TCL), and ellipse line measurement of the whole spine, excluding the sacrum and coccyx (EL). We compared these anthropometric PMCT measurements with AL and correlated them using linear regression analysis. RESULTS: The results showed a significant linear relationship existed between TL and LS with AL, which was higher in comparison with the other parameters than the rest of the spine parameters. The linear regression formula derived was: 48.163 + 2.458 (TL) + 2.246 (LS). CONCLUSIONS: The linear regression formula derived from PMCT spine length parameters particularly thoracic and lumbar spine gave a finer correlation with autopsy body length and can be used for accurate estimation of cadaveric height. To the best of our knowledge, this is the first ever linear regression formula for cadaveric height assessment using only post mortem CT spine length measurements.


Subject(s)
Body Height , Cadaver , Forensic Anthropology/methods , Spine/diagnostic imaging , Adult , Aged , Autopsy , Female , Humans , Linear Models , Male , Middle Aged , Tomography, X-Ray Computed
8.
Med J Malaysia ; 75(5): 561-567, 2020 09.
Article in English | MEDLINE | ID: mdl-32918427

ABSTRACT

INTRODUCTION: This study aimed to validate the Malay version of the short form Smartphone Addiction Scale (SAS-M-SF) and to examine its psychometric properties in a cohort of pre-university adolescents. METHODS: We obtained the validity and reliability evidence for the SAS-M-SF using a group of 307 pre-university students in Universiti Putra Malaysia (UPM), Serdang, Selangor, Malaysia with a mean age of 18.4±0.2 years (70.4% female and 29.6% male). A questionnaire containing the Malay version of Smartphone Addiction Scale (SAS-M), the Malay version of the short form Smartphone Addiction Scale (SAS-M-SF), and the Malay version of the Internet Addiction Test (IAT-M) was administered on the adolescents. RESULTS: The SAS-M-SF displayed good internal consistency (Cronbach's α=0.80). Using principle component analysis, we identified a 4-factor SAS-M-SF model. A significant correlation between the SAS-M-SF and the IAT-M was found, lending support for concurrent validity. The prevalence of smartphone addiction was 54.5% based on cut-off score of ≥36 with a sensitivity of 70.2% and a specificity of 72.5%. CONCLUSIONS: The 10-item SAS-M-SF is a valid and reliable screening tool for smartphone addiction among adolescents. The scale can help clinicians or educators design appropriate intervention and prevention programs targeting smartphone addiction in adolescents at clinical or school settings.


Subject(s)
Internet Addiction Disorder , Smartphone , Surveys and Questionnaires/standards , Adolescent , Cross-Sectional Studies , Female , Humans , Internet Addiction Disorder/epidemiology , Malaysia/epidemiology , Male , Psychometrics
9.
Med J Malaysia ; 75(4): 356-362, 2020 07.
Article in English | MEDLINE | ID: mdl-32723994

ABSTRACT

OBJECTIVE: Problematic smartphone use (PSU) is the development of pathological dependence at the expense of performing activities of daily living, thus having negative health and psychological impact on the users. Previous PSU studies focused on medical students and little is known regarding its effect on students undergoing other courses. The objective of this study is to identify the pattern of smartphone usage and determine the psychological factors affecting PSU among undergraduate students in Malaysia and compare the pattern among students from different fields of study. METHOD: A prospective cross-sectional study was conducted using the validated Smartphone Addiction Scale-Malay version (SAS-M) questionnaire. One-way ANOVA was used to determine the correlation between the PSU among the students categorised by their ethnicity, hand dominance and by their field of study. MLR analysis was applied to predict PSU based on socio-demographic data, usage patterns, psychological factors and fields of study. RESULTS: A total of 1060 students completed the questionnaire. Most students had some degree of problematic usage of the smartphone. Students used smartphones predominantly to access SNAs, namely Instagram. Longer duration on the smartphone per day, younger age at first using a smartphone and underlying depression carried higher risk of developing PSU, whereas the field of study (science vs. humanities based) did not contribute to an increased risk of developing PSU. CONCLUSION: Findings from this study can help better inform university administrators about at- risk groups of undergraduate students who may benefit from targeted intervention designed to reduce their addictive behaviour patterns.


Subject(s)
Smartphone , Students , Universities , Cross-Sectional Studies , Female , Humans , Malaysia , Male , Mental Health , Prospective Studies , Surveys and Questionnaires
10.
Med J Malaysia ; 75(4): 411-418, 2020 07.
Article in English | MEDLINE | ID: mdl-32724006

ABSTRACT

INTRODUCTION: Autopsy is one of the most important approaches to identify clearly the exact cause of death, whether it was due to natural causes, sudden death, or traumatic. Various studies have been done in different countries regarding ways to improve the diagnosis during autopsy. The imaging approach is one of the methods that has been used to complement autopsy findings and to enhance the diagnosis for achieving the most accurate post-mortem diagnosis. The aim of this study is to identify the role of imaging modalities that complement routine autopsy and correlate the findings of diagnostic imaging that can help improve the accuracy of diagnosing the cause of death. METHODS: We sourced articles from Scopus, Ovid and PubMed databases for journal publications related to post-mortem diagnostic imaging. We highlight the most relevant full articles in English that explain the type of modality that was utilised and the added value it provided for diagnosing the cause of death. RESULTS: Minimally invasive autopsies assisted by imaging modalities added a great benefit to forensic medicine, and supported conventional autopsy. In particular the role of post mortem computed tomography (PMCT), post mortem computed tomography angiography (PMMR) and positron emission tomography computed tomography (PMCTA) that have incremental benefits in diagnosing traumatic death, fractures, tissue injuries, as well as the assessment of body height or weight for corpse identification. CONCLUSION: PMCT and PMMR, with particular emphasis on PMCTA, can provide higher accuracy than the other modalities. They can be regarded as indispensable methods that should be applied to the routine autopsy protocol, thus improving the findings and accuracy of diagnosing the cause of death.


Subject(s)
Autopsy/methods , Cause of Death , Tomography, X-Ray Computed/methods , Forensic Medicine , Humans , Malaysia
11.
Med J Malaysia ; 73(3): 141-146, 2018 06.
Article in English | MEDLINE | ID: mdl-29962497

ABSTRACT

BACKGROUND: Imaging such as Tc99m-HMPAO single photon emission computed tomography (SPECT), and positron emission tomography/ computed tomography (PET/CT) amyloid scans are used to aid the diagnosis of Alzheimer's disease (AD). OBJECTIVE: We aimed to correlate the ability of these modalities to differentiate Probable AD and Possible AD using the clinical diagnosis as a gold standard. We also investigated the correlation of severity of amyloid deposit in the brain with the diagnosis of AD. METHODS: A retrospective study of 47 subjects (17 Probable AD and 30 Possible AD) who were referred for PET/CT amyloid scans to our centre was conducted. Hypoperfusion in the temporo-parietal lobes on Tc99m-HMPAO SPECT and loss of grey-white matter contrast in cortical regions on PET/CT Amyloid scans indicating the presence of amyloid ß deposit were qualitatively interpreted as positive for AD. SPECT and PET/CT were also read in combination (Combo reading). The severity of amyloid ß deposit was semiquantitatively assessed in a visual binary method using a scale of Grade 0-4. The severity of amyloid ß deposit was assessed in a visual binary method and a semi-quantitative method using a scale of Grade 0-4. RESULTS: There was significant correlation of Tc99m-HMPAO SPECT, PET/CT amyloid findings and Combo reading with AD. The sensitivity, specificity, PPV and NPV were 87.5%, 73.7%, 58.3% and 93.3% (SPECT); 62.5%, 77.4%, 58.8% and 80.0% (PET/CT) and 87.5%, 84.2%, 70.0% and 30.0% (Combo reading) respectively. The grade of amyloid deposition was not significantly correlated with AD (Spearman's correlation, p=0.687). CONCLUSION: There is an incremental benefit in utilizing PET/CT amyloid imaging in cases with atypical presentation and indeterminate findings on conventional imaging of Alzheimer's disease.


Subject(s)
Alzheimer Disease/diagnostic imaging , Brain/diagnostic imaging , Adult , Aged , Aged, 80 and over , Alzheimer Disease/diagnosis , Amyloid beta-Peptides/metabolism , Female , Humans , Male , Middle Aged , Neuroimaging , Positron-Emission Tomography , Retrospective Studies , Technetium Tc 99m Exametazime , Tomography, Emission-Computed, Single-Photon
13.
Prog Biophys Mol Biol ; 113(2): 289-94, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24080185

ABSTRACT

The potential of organic semiconductor based devices for light generation is demonstrated by the commercialisation of display technologies using organic light emitting diode (OLED). In OLED, organic materials plays an important role of emitting light once the current is passed through. However OLED have drawbacks whereby it suffers from photon loss and exciton quenching. Organic light emitting transistor (OLET) emerged as a new technology to compensate the efficiency and brightness loss encountered in OLED. The structure has combinational capability to switch the electronic signal such as the field effect transistor (FET) as well as to generate light. Different colours of light could be generated by using different types of organic material. The light emission could also be tuned and scanned in OLET. The studies carried out in this paper focuses on investigation of fabricated MEH-PPV based OLED and also OLET via current voltage characteristics. These studies will continue with a view to develop an optimised MEH-PPV based OLET.


Subject(s)
Lighting/instrumentation , Organic Chemicals/chemistry , Semiconductors , Transistors, Electronic , Electric Conductivity , Electron Transport , Equipment Design , Equipment Failure Analysis
14.
Clin Radiol ; 68(9): e502-10, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23706826

ABSTRACT

AIM: To investigate the diagnostic accuracy of single-voxel proton magnetic resonance spectroscopy (SV (1)H MRS) by quantifying total choline-containing compounds (tCho) in differentiating malignant from benign lesions, and subsequently, to analyse the relationship of tCho levels in malignant breast lesions with their histopathological subtypes. MATERIALS AND METHODS: A prospective study of SV 1H MRS was performed following dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in 61 women using a 3 T MR system. All lesions (n = 57) were analysed for characteristics of morphology, contrast-enhancement kinetics, and tCho peak heights at SV (1)H MRS that were two-times above baseline. Subsequently, the tCho in selected lesions (n = 32) was quantified by calculating the area under the curve, and a tCho concentration equal to or greater than the cut-off value was considered to represent malignancy. The relationship between tCho in invasive ductal carcinomas (IDCs) and their Bloom & Richardson grading of malignancy was assessed. RESULTS: Fifty-two patients (57 lesions; 42 malignant and 15 benign) were analysed. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), of predicting malignancy were 100, 73.3, 91.3, and 100%, respectively, using DCE-MRI and 95.2, 93.3, 97.6, and 87.5%, respectively, using SV (1)H MRS. The tCho cut-off for receiver operating characteristic (ROC) curve was 0.33 mmol/l. The relationship between tCho levels in malignant breast lesions with their histopathological subtypes was not statistically significant (p = 0.3). CONCLUSION: Good correlation between tCho peaks and malignancy, enables SV (1)H MRS to be used as a clinically applicable, simple, yet non-invasive tool for improved specificity and diagnostic accuracy in detecting breast cancer.


Subject(s)
Breast Neoplasms/diagnosis , Carcinoma, Ductal, Breast/diagnosis , Protons , Adult , Aged , Aged, 80 and over , Breast/chemistry , Choline/analysis , Early Detection of Cancer/methods , Female , Humans , Magnetic Resonance Imaging/methods , Magnetic Resonance Spectroscopy/methods , Middle Aged , Prospective Studies , Sensitivity and Specificity , Young Adult
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