Displaying publications 81 - 100 of 116 in total

Abstract:
Sort:
  1. Shatriah I, Norazizah MA, Wan-Hitam WH, Wong AR, Yunus R, Leo SW
    Pediatr Dermatol, 2013 Jan-Feb;30(1):151-4.
    PMID: 22329437 DOI: 10.1111/j.1525-1470.2011.01618.x
    High intraocular pressure is a rare ophthalmic condition associated with infantile hemangiomas that involves the orbit, eyelid, or both. Here, we describe a patient with extensive facial and orbital infantile hemangiomas associated with high intraocular pressure in the affected eye. The prompt management of this challenging condition is essential.
    Matched MeSH terms: Magnetic Resonance Imaging/methods
  2. Mohd Zaki F, Moineddin R, Grant R, Chavhan GB
    Pediatr Radiol, 2016 Nov;46(12):1684-1693.
    PMID: 27406610
    BACKGROUND: Safety concerns are increasingly raised regarding the use of gadolinium-based contrast media for MR imaging.

    OBJECTIVE: To determine the accuracy of pre-contrast abdominal MR imaging for lesion detection and characterization in pediatric oncology patients.

    MATERIALS AND METHODS: We included 120 children (37 boys and 83 girls; mean age 8.94 years) referred by oncology services. Twenty-five had MRI for the first time and 95 were follow-up scans. Two authors independently reviewed pre-contrast MR images to note the following information about the lesions: location, number, solid vs. cystic and likely nature. Pre- and post-contrast imaging reviewed together served as the reference standard.

    RESULTS: The overall sensitivity was 88% for the first reader and 90% for the second; specificity was 94% and 91%; positive predictive value was 96% and 94%; negative predictive value was 82% and 84%; accuracy of pre-contrast imaging for lesion detection as compared to the reference standard was 90% for both readers. The difference between mean number of lesions detected on pre-contrast imaging and reference standard was not significant for either reader (reader 1, P = 0.072; reader 2, P = 0.071). There was substantial agreement (kappa values of 0.76 and 0.72 for readers 1 and 2) between pre-contrast imaging and reference standard for determining solid vs. cystic lesion and likely nature of the lesion. The addition of post-contrast imaging increased confidence of both readers significantly (P 

    Matched MeSH terms: Magnetic Resonance Imaging/methods*
  3. Thambidorai CR, Raghu R, Zulfiqar A
    Pediatr Surg Int, 2008 Feb;24(2):161-5.
    PMID: 17985137
    Different criteria have been used in literature to describe the anterior ectopic anus (AEA) anomaly, resulting in uncertainty over its prevalence, association with constipation and definition of the indications for surgery. It has been recently proposed that the term AEA should be restricted to anomalies in which a normal appearing anal orifice is located in the perineum in a more anterior location than normal, with an anal canal of normal calibre that is shown by electrical stimulation to be surrounded by the voluntary external anal sphincter (EAS). We report about four infants, three females and one male, who presented with constipation and had an anteriorly located anal orifice of normal calibre. The anal position index measured clinically was less than 0.34 in all the female patients and 0.44 in the male patient. In preoperative magnetic resonance imaging (MRI), the EAS was distributed all around the circumference of the anal canal, including the ventral aspect of the anal canal, in all the patients. Preoperative MRI documentation of sphincter distribution is recommended for the diagnosis of AEA, as it would help in better definition of its association with constipation and the results of surgical management.
    Matched MeSH terms: Magnetic Resonance Imaging/methods*
  4. Jahanzad Z, Liew YM, Bilgen M, McLaughlin RA, Leong CO, Chee KH, et al.
    Phys Med Biol, 2015 May 21;60(10):4015-31.
    PMID: 25919317 DOI: 10.1088/0031-9155/60/10/4015
    A segmental two-parameter empirical deformable model is proposed for evaluating regional motion abnormality of the left ventricle. Short-axis tagged MRI scans were acquired from 10 healthy subjects and 10 postinfarct patients. Two motion parameters, contraction and rotation, were quantified for each cardiac segment by fitting the proposed model using a non-rigid registration algorithm. The accuracy in motion estimation was compared to a global model approach. Motion parameters extracted from patients were correlated to infarct transmurality assessed with delayed-contrast-enhanced MRI. The proposed segmental model allows markedly improved accuracy in regional motion analysis as compared to the global model for both subject groups (1.22-1.40 mm versus 2.31-2.55 mm error). By end-systole, all healthy segments experienced radial displacement by ~25-35% of the epicardial radius, whereas the 3 short-axis planes rotated differently (basal: 3.3°; mid:  -1° and apical:  -4.6°) to create a twisting motion. While systolic contraction showed clear correspondence to infarct transmurality, rotation was nonspecific to either infarct location or transmurality but could indicate the presence of functional abnormality. Regional contraction and rotation derived using this model could potentially aid in the assessment of severity of regional dysfunction of infarcted myocardium.
    Matched MeSH terms: Magnetic Resonance Imaging/methods*
  5. Yazdani S, Yusof R, Karimian A, Mitsukira Y, Hematian A
    PLoS One, 2016;11(4):e0151326.
    PMID: 27096925 DOI: 10.1371/journal.pone.0151326
    Image segmentation of medical images is a challenging problem with several still not totally solved issues, such as noise interference and image artifacts. Region-based and histogram-based segmentation methods have been widely used in image segmentation. Problems arise when we use these methods, such as the selection of a suitable threshold value for the histogram-based method and the over-segmentation followed by the time-consuming merge processing in the region-based algorithm. To provide an efficient approach that not only produce better results, but also maintain low computational complexity, a new region dividing based technique is developed for image segmentation, which combines the advantages of both regions-based and histogram-based methods. The proposed method is applied to the challenging applications: Gray matter (GM), White matter (WM) and cerebro-spinal fluid (CSF) segmentation in brain MR Images. The method is evaluated on both simulated and real data, and compared with other segmentation techniques. The obtained results have demonstrated its improved performance and robustness.
    Matched MeSH terms: Magnetic Resonance Imaging/methods*
  6. Siddiqui MF, Reza AW, Kanesan J
    PLoS One, 2015;10(8):e0135875.
    PMID: 26280918 DOI: 10.1371/journal.pone.0135875
    A wide interest has been observed in the medical health care applications that interpret neuroimaging scans by machine learning systems. This research proposes an intelligent, automatic, accurate, and robust classification technique to classify the human brain magnetic resonance image (MRI) as normal or abnormal, to cater down the human error during identifying the diseases in brain MRIs. In this study, fast discrete wavelet transform (DWT), principal component analysis (PCA), and least squares support vector machine (LS-SVM) are used as basic components. Firstly, fast DWT is employed to extract the salient features of brain MRI, followed by PCA, which reduces the dimensions of the features. These reduced feature vectors also shrink the memory storage consumption by 99.5%. At last, an advanced classification technique based on LS-SVM is applied to brain MR image classification using reduced features. For improving the efficiency, LS-SVM is used with non-linear radial basis function (RBF) kernel. The proposed algorithm intelligently determines the optimized values of the hyper-parameters of the RBF kernel and also applied k-fold stratified cross validation to enhance the generalization of the system. The method was tested by 340 patients' benchmark datasets of T1-weighted and T2-weighted scans. From the analysis of experimental results and performance comparisons, it is observed that the proposed medical decision support system outperformed all other modern classifiers and achieves 100% accuracy rate (specificity/sensitivity 100%/100%). Furthermore, in terms of computation time, the proposed technique is significantly faster than the recent well-known methods, and it improves the efficiency by 71%, 3%, and 4% on feature extraction stage, feature reduction stage, and classification stage, respectively. These results indicate that the proposed well-trained machine learning system has the potential to make accurate predictions about brain abnormalities from the individual subjects, therefore, it can be used as a significant tool in clinical practice.
    Matched MeSH terms: Magnetic Resonance Imaging/methods
  7. Usman OL, Muniyandi RC, Omar K, Mohamad M
    PLoS One, 2021;16(2):e0245579.
    PMID: 33630876 DOI: 10.1371/journal.pone.0245579
    Achieving biologically interpretable neural-biomarkers and features from neuroimaging datasets is a challenging task in an MRI-based dyslexia study. This challenge becomes more pronounced when the needed MRI datasets are collected from multiple heterogeneous sources with inconsistent scanner settings. This study presents a method of improving the biological interpretation of dyslexia's neural-biomarkers from MRI datasets sourced from publicly available open databases. The proposed system utilized a modified histogram normalization (MHN) method to improve dyslexia neural-biomarker interpretations by mapping the pixels' intensities of low-quality input neuroimages to range between the low-intensity region of interest (ROIlow) and high-intensity region of interest (ROIhigh) of the high-quality image. This was achieved after initial image smoothing using the Gaussian filter method with an isotropic kernel of size 4mm. The performance of the proposed smoothing and normalization methods was evaluated based on three image post-processing experiments: ROI segmentation, gray matter (GM) tissues volume estimations, and deep learning (DL) classifications using Computational Anatomy Toolbox (CAT12) and pre-trained models in a MATLAB working environment. The three experiments were preceded by some pre-processing tasks such as image resizing, labelling, patching, and non-rigid registration. Our results showed that the best smoothing was achieved at a scale value, σ = 1.25 with a 0.9% increment in the peak-signal-to-noise ratio (PSNR). Results from the three image post-processing experiments confirmed the efficacy of the proposed methods. Evidence emanating from our analysis showed that using the proposed MHN and Gaussian smoothing methods can improve comparability of image features and neural-biomarkers of dyslexia with a statistically significantly high disc similarity coefficient (DSC) index, low mean square error (MSE), and improved tissue volume estimations. After 10 repeated 10-fold cross-validation, the highest accuracy achieved by DL models is 94.7% at a 95% confidence interval (CI) level. Finally, our finding confirmed that the proposed MHN method significantly outperformed the normalization method of the state-of-the-art histogram matching.
    Matched MeSH terms: Magnetic Resonance Imaging/methods*
  8. Balasingam S, Azman RR, Nazri M
    QJM, 2016 Feb;109(2):121-2.
    PMID: 26101228 DOI: 10.1093/qjmed/hcv121
    Matched MeSH terms: Magnetic Resonance Imaging/methods
  9. Hani AF, Kumar D, Malik AS, Ahmad RM, Razak R, Kiflie A
    Rheumatol Int, 2015 Jan;35(1):1-16.
    PMID: 24879325 DOI: 10.1007/s00296-014-3052-9
    Early detection of knee osteoarthritis (OA) is of great interest to orthopaedic surgeons, rheumatologists, radiologists, and researchers because it would allow physicians to provide patients with treatments and advice to slow the onset or progression of the disease. Early detection can be achieved by identifying early changes in selected features of degenerative articular cartilage (AC) using non-invasive imaging modalities. Magnetic resonance imaging (MRI) is becoming the standard for assessment of OA. The aim of this paper was to review the influence of MRI on the selection, detection, and measurement of AC features associated with early OA. Our review of the literature indicates that the changes associated with early OA are in cartilage thickness, cartilage volume, cartilage water content, and proteoglycan content that can be accurately, consistently, and non-invasively measured using MRI. Choosing an MR pulse sequence that provides the capability to assess cartilage physiology and morphology in a single acquisition and advanced multi-nuclei MRI is desirable. The results of the review indicate that using an ultra-high magnetic strength, MR imager does not affect early OA detection. In conclusion, MRI is currently the most suitable modality for early detection of knee OA, and future research should focus on the quantitative evaluation of early OA features using advances in MR hardware, software, and data processing with sophisticated image/pattern recognition techniques.
    Matched MeSH terms: Magnetic Resonance Imaging/methods*
  10. Tan HK, Bakri MM, Peh WC
    Semin Musculoskelet Radiol, 2014 Feb;18(1):45-53.
    PMID: 24515881 DOI: 10.1055/s-0034-1365834
    MR imaging is an established tool for the detection and diagnosis of various injuries and internal derangements of the knee, enabling excellent anatomical visualization and producing good soft tissue contrast and characterization. However, numerous normal variants and potential pitfalls may lead to diagnostic errors. Understanding the basic MR imaging principles, applying the correct technique, knowing the normal anatomy and variants, recognizing artifacts, and assuring good clinical and radiographic correlation helps avoid these potential pitfalls.
    Matched MeSH terms: Magnetic Resonance Imaging/methods*
  11. Wong KA, Singh VA, Pailoor J
    Singapore Med J, 2013 Nov;54(11):e228-9.
    PMID: 24276110
    Intra-articular haemangioma is a rare and uncommon condition that sometimes presents in infants. The lesion can be a diagnostic challenge, with misdiagnosis often leading to delayed diagnosis and treatment. It is essential to establish and treat the condition early, as intra-articular haemangioma can lead to destruction of the joint and secondary arthrosis. Herein, we report the case of a five-year-old boy who presented with intra-articular haemangioma and discuss the management of his condition.
    Matched MeSH terms: Magnetic Resonance Imaging/methods*
  12. Chew YK, Noorizan Y, Khir A, Brito-Mutunayagam S, Prepageran N
    Singapore Med J, 2009 Nov;50(11):e374-5.
    PMID: 19960147
    The incidence of mucocoeles associated with a non-surgically treated nasal polyposis is rare. We report a rare case of nasal polyposis with asymptomatic frontal mucocoeles in a 28-year-old Malay man who presented with bilateral nasal obstruction with anosmia. Physical examination revealed bilateral grade III nasal polyps causing obstruction. Computed tomography revealed paranasal polyposis with a large polyp extending and expanding the posterior table of the frontal sinus causing erosion and thinning of its wall. Marsupialisation of the mucocoele and nasal polypectomy were done. Endoscopic sinus surgery and marsupialisation should be the treatment of choice for asymptomatic frontal mucocoele.
    Matched MeSH terms: Magnetic Resonance Imaging/methods
  13. Wong CY, Azizi AB, Shareena I, Rohana J, Boo NY, Isa MR
    Singapore Med J, 2010 Oct;51(10):e166-8.
    PMID: 21103805
    Brain herniation is generally thought to be unlikely to occur in newborns due to the presence of the patent fontanelles and cranial sutures. A review of the literature published from 1993 to 2008 via MEDLINE search revealed no reports on neonatal brain herniation from intracranial tumour. We report a preterm Malay male infant born via elective Caesarean section for antenatally diagnosed intracerebral tumour, which subsequently developed herniation. Cerebral magnetic resonance imaging showed features that were compatible with a large complex intracranial tumour causing mass effect and gross hydrocephalus. Tumour excision was scheduled when the infant was two weeks old. Unfortunately, on the morning of the surgery, he developed signs of brain herniation and had profuse tumour haemorrhage during the attempted excision. Histopathological examination revealed an embryonal tumour, possibly an atypical rhabdoid/teratoid tumour. This case illustrates that intracranial tumours in newborns can herniate and should therefore be closely monitored.
    Matched MeSH terms: Magnetic Resonance Imaging/methods
  14. Megat Shiraz MA, Jong YH, Primuharsa Putra SH
    Singapore Med J, 2008 Nov;49(11):e310-1.
    PMID: 19037537
    Extramedullary plasmacytoma is a rare malignant plasma cell tumour. We report an extremely aggressive case of extramedullary plasmacytoma of the right maxillary sinus, which had metastasised to the brain and rib. A 56-year-old man presented with recurrent epistaxis and acute anaemia. Nasendoscopy revealed a medialised medial wall of the right maxilla and a mass occupying the whole nasopharynx. Magnetic resonance imaging revealed a right maxillary tumour with extension to the ipsilateral nasal cavity, nasopharynx, right sphenoid and ethmoidal sinuses. There was an extra-axial brain metastasis. There were metastases to the right parietal region and left eighth rib. Histopathology examination of the maxillary mass revealed abundant plasma cells with kappa-chain restriction. He was planned for four cycles of chemotherapy. Unfortunately, in view of the advanced stage of disease, he succumbed to his disease during the first cycle of chemotherapy.
    Matched MeSH terms: Magnetic Resonance Imaging/methods
  15. Voon NS, Manan HA, Yahya N
    Strahlenther Onkol, 2023 Aug;199(8):706-717.
    PMID: 37280382 DOI: 10.1007/s00066-023-02089-3
    PURPOSE: Increasing evidence implicates changes in brain function following radiotherapy for head and neck cancer as precursors for brain dysfunction. These changes may thus be used as biomarkers for early detection. This review aimed to determine the role of resting-state functional magnetic resonance imaging (rs-fMRI) in detecting brain functional changes.

    METHODS: A systematic search was performed in the PubMed, Scopus, and Web of Science (WoS) databases in June 2022. Patients with head and neck cancer treated with radiotherapy and periodic rs-fMRI assessments were included. A meta-analysis was performed to determine the potential of rs-fMRI for detecting brain changes.

    RESULTS: Ten studies with a total of 513 subjects (head and neck cancer patients, n = 437; healthy controls, n = 76) were included. A significance of rs-fMRI for detecting brain changes in the temporal and frontal lobes, cingulate cortex, and cuneus was demonstrated in most studies. These changes were reported to be associated with dose (6/10 studies) and latency (4/10 studies). A strong effect size (r = 0.71, p 

    Matched MeSH terms: Magnetic Resonance Imaging/methods
  16. Hoe HG, Zaki FM, Rashid AHA
    Sultan Qaboos Univ Med J, 2018 Feb;18(1):e93-e96.
    PMID: 29666688 DOI: 10.18295/squmj.2018.18.01.015
    Synovial haemangiomas are rare benign vascular proliferations arising in synovium-lined surfaces. While the knee is by far the joint most commonly involved, this condition can also occur in the elbow. We report an eight-year-old boy who presented to the National University of Malaysia Medical Centre, Kuala Lumpur, Malaysia, in 2016 with a left elbow swelling of one year's duration. Magnetic resonance imaging showed a lobulated intra-articular mass with intermediate signal intensity on T1-weighted imaging and low signal punctate and linear structures within the hyperintense mass on T2-weighted imaging. In addition, there was heterogeneous yet avid contrast enhancement on post-gadolinium contrast images. The mass had juxta-articular extension and bony erosion to the coronoid process and the head of the radius. Synovial haemangiomas present a diagnostic dilemma. This report highlights certain imaging characteristics to distinguish this entity from other differential diagnoses.
    Matched MeSH terms: Magnetic Resonance Imaging/methods*
  17. Tan HH, Tan SK, Shunmugan R, Zakaria R, Zahari Z
    Sultan Qaboos Univ Med J, 2017 Nov;17(4):e455-e459.
    PMID: 29372089 DOI: 10.18295/squmj.2017.17.04.013
    Persistent urogenital sinus (PUGS) is a rare anomaly whereby the urinary and genital tracts fail to separate during embryonic development. We report a three-year-old female child who was referred to the Sabah Women & Children Hospital, Sabah, Malaysia, in 2016 with a pelvic mass. She had been born prematurely at 36 gestational weeks via spontaneous vaginal delivery in 2013 and initially misdiagnosed with neurogenic bladder dysfunction. The external genitalia appeared normal and an initial sonogram and repeat micturating cystourethrograms did not indicate any urogenital anomalies. She therefore underwent clean intermittent catheterisation. Three years later, the diagnosis was corrected following the investigation of a persistent cystic mass posterior to the bladder. At this time, a clinical examination of the perineum showed a single opening into the introitus. Magnetic resonance imaging of the pelvis revealed gross hydrocolpos and a genitogram confirmed a diagnosis of PUGS, for which the patient underwent surgical separation of the urinary and genital tracts.
    Matched MeSH terms: Magnetic Resonance Imaging/methods
  18. Yusof MI, Hassan E, Abdullah S
    Surg Radiol Anat, 2011 Mar;33(2):109-15.
    PMID: 20658232 DOI: 10.1007/s00276-010-0704-7
    Posterior translation of the spinal cord occurs passively following laminoplasty with the presence lordotic spine and availability of a space for the spinal cord to shift. This study is to predict the distance of posterior spinal cord migration after expansive laminoplasty at different cervical levels based on measurement of posterior translation of the spinal cord in normal cervical morphometry.
    Matched MeSH terms: Magnetic Resonance Imaging/methods*
  19. Ahmad RF, Malik AS, Kamel N, Reza F, Amin HU, Hussain M
    Technol Health Care, 2017;25(3):471-485.
    PMID: 27935575 DOI: 10.3233/THC-161286
    BACKGROUND: Classification of the visual information from the brain activity data is a challenging task. Many studies reported in the literature are based on the brain activity patterns using either fMRI or EEG/MEG only. EEG and fMRI considered as two complementary neuroimaging modalities in terms of their temporal and spatial resolution to map the brain activity. For getting a high spatial and temporal resolution of the brain at the same time, simultaneous EEG-fMRI seems to be fruitful.

    METHODS: In this article, we propose a new method based on simultaneous EEG-fMRI data and machine learning approach to classify the visual brain activity patterns. We acquired EEG-fMRI data simultaneously on the ten healthy human participants by showing them visual stimuli. Data fusion approach is used to merge EEG and fMRI data. Machine learning classifier is used for the classification purposes.

    RESULTS: Results showed that superior classification performance has been achieved with simultaneous EEG-fMRI data as compared to the EEG and fMRI data standalone. This shows that multimodal approach improved the classification accuracy results as compared with other approaches reported in the literature.

    CONCLUSIONS: The proposed simultaneous EEG-fMRI approach for classifying the brain activity patterns can be helpful to predict or fully decode the brain activity patterns.

    Matched MeSH terms: Magnetic Resonance Imaging/methods*
  20. Choo WS, Steeds RP
    Br J Radiol, 2011 Dec;84 Spec No 3:S245-57.
    PMID: 22723532 DOI: 10.1259/bjr/54030257
    The aim of this article is to provide a perspective on the relative importance and contribution of different imaging modalities in patients with valvular heart disease. Valvular heart disease is increasing in prevalence across Europe, at a time when the clinical ability of physicians to diagnose and assess severity is declining. Increasing reliance is placed on echocardiography, which is the mainstay of cardiac imaging in valvular heart disease. This article outlines the techniques used in this context and their limitations, identifying areas in which dynamic imaging with cardiovascular magnetic resonance and multislice CT are expanding.
    Matched MeSH terms: Magnetic Resonance Imaging/methods
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links