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Autoimmune haemolytic anaemia in pregnancy: a case report

Ng SC, Wong KK, Raman S, Bosco J

Eur J Obstet Gynecol Reprod Biol, 1990 Oct;37(1):83-5.
PMID: 2376282

A young primigravida had idiopathic warm antibody (IgG) autoimmune haemolytic anaemia (AIHA) occurring in the third trimester of pregnancy. Her haemolytic process was responsive to steroid therapy and no transfusion was needed. She delivered a healthy baby with no evidence to haemolysis, though his red cells were coated with IgG which was probably of maternal origin.
Acute organic brain syndrome due to drug-induced eosinophilia

Ng SC, Lee MK, Teh A

Postgrad Med J, 1989 Nov;65(769):843-4.
PMID: 2616421

A 72 year old man developed acute organic brain syndrome associated with marked eosinophilia following self medication with a variety of drugs. Investigations revealed no other known causes of eosinophilia. Withdrawal of drugs resulted in dramatic drop in eosinophil count paralleled by clinical resolution of neurological problems. To our knowledge drug-induced eosinophilia has not previously been associated with acute organic brain syndrome.
Hybrid acute leukaemia--a report of 3 cases

Ng SC, Wong TK, Lin HP

Ann Acad Med Singap, 1989 Nov;18(6):721-3.
PMID: 2624424

The simultaneous expression of both lymphoid and myeloid phenotypic features in acute leukaemia is rare. We report 3 cases of biphenotypic hybrid acute leukaemia seen in our institution. All 3 patients achieved remission with treatment for acute lymphoblastic leukaemia but two subsequently relapsed while on treatment. The hybrid acute leukaemias are important areas for further research both for delineation of basic biology and choice of optimal treatment.
Comparison between FEV1/FEV6 and FEV1/FVC as screening of chronic obstructive pulmonary disease

Ng SC, Abu Samah F, Helmy K, Sia KK

Med J Malaysia, 2017 10;72(5):286-290.
PMID: 29197884 MyJurnal

OBJECTIVE: To compare FEV1/FEV6 to the standard spirometry (FEV1/FVC) as a screening tool for COPD.
METHODS: This cross-sectional study was conducted at Hospital Tuanku Fauziah, Perlis, Malaysia from August 2015 to April 2016. FEV1/FEV6 and FEV1/FVC results of 117 subjects were analysed. Demographic data and spirometric variables were tabulated. A scatter plot graph with Spearman's correlation was constructed for the correlation between FEV1/FEV6 and FEV1/FVC. The sensitivity, specificity, positive and negative predictive values of FEV1/FEV6 were determined with reference to the gold standard of FEV1/FVC ratio <0.70. Receiver-operator characteristic (ROC) curve analysis and Kappa statistics were used to determine the FEV1/FEV6 ratio in predicting an FEV1/FVC ratio <0.70.
RESULTS: Spearman's correlation with r = 0.636 (P<0.001) was demonstrated. The area under the ROC curve was 0.862 (95% confidence interval [CI]: 0.779 - 0.944, P<0.001). The FEV1/FEV6 cut-off with the greatest sum of sensitivity and specificity was 0.75. FEV1/FEV6 sensitivity, specificity, positive and negative predictive values were 93.02%, 67.74%, 88.89% and 77.78% respectively. There was substantial agreement between the two diagnostic cut-offs (κ = 0.634; 95% CI: 0.471 - 0.797, P<0.001) CONCLUSIONS: The FEV1/FEV6 ratio can be considered to be a good alternative to the FEV1/FVC ratio for screening of COPD. Larger multicentre study and better education on spirometric techniques can validate similar study outcome and establish reference values appropriate to the population being studied.
Fulltext Myelodysplastic syndrome: a review from University Hospital, Kuala Lumpur

Ng SC, Kuperan P, Bosco J, Menaka N

Singapore Med J, 1990 Apr;31(2):153-8.
PMID: 2196685

Twenty patients with Myelodysplastic Syndrome (MDS) were diagnosed in University Hospital, Kuala Lumpur over a 5 year period. They were subclassified using the French American British (FAB) criteria. 90% of the patients were above 40 years old and the sex ratio was about equal. The predominant presenting symptom was anaemia and there was paucity of physical signs at presentation. Patients with 'aggressive' subtypes of MDS i.e. refractory anaemia with excess blasts (RAEB), refractory anaemia with excess blasts in transformation (RAEB(-)+) and chronic myelomonocytic leukaemia (CMML) had more frequent thrombocytopenia and neutropenia and their marrow pictures frequently had dysmegakaryopoiesis and dysgranulopoiesis as compared to more the "benign" subtypes i.e. refractory anaemia (RA) and refractory leukaemic anaemia with ringed sideroblasts (RARS). Four patients had leukaemic transformation and all of them came from the 'aggressive' subtypes. The current views on treatment of MDS are discussed.
Fulltext Splenic lymphoma with hypersplenism--a case report

Ng SC, Kuperan P, Jayalakshmi P, Chua CT

Singapore Med J, 1990 Feb;31(1):80-2.
PMID: 2185555

A 47-year old man had hypersplenism from massive splenomegaly, the cause of which was undetermined for 2 years. He was initially asymptomatic though there was mild pancytopenia. However, 18 months after presentation he manifested both clinical and haematological deterioration, almost succumbing to sepsis. Splenectomy finally provided a definite diagnosis of follicular lymphoma and also restored his blood counts to within normal range.
Fulltext The Use of the Self-Standing Turning Transfer Device to Perform Bed-To-Chair Transfers Reduces Physical Stress among Caregivers of Older Patients in a Middle-Income Developing Country

Goh CH, Muslimah Y, Ng SC, Subramanian P, Tan MP

Front Med (Lausanne), 2014;1:32.
PMID: 25593906 DOI: 10.3389/fmed.2014.00032

Manual transfer of elderly patients remains commonplace in many developing countries because the use of lifting equipment, such as hoists, is often considered unaffordable luxuries. The aim of this study was, therefore, to evaluate the usage and potential benefits of a low-cost, mechanical turning transfer device among elderly patients and their caregivers on a geriatric ward in a developing country in South East Asia. Fifty-six inpatients, aged 66-92 years, on a geriatric ward, and their caregivers were recruited. Participants were asked to transfer from bed-to-chair transfer with manual assistance, and the task was repeated using the Self-standing Turning Transfer Device (STurDi). The time taken to perform manual transfers and STurDi-assisted transfers was recorded. Physical strain was assessed using the perceived physical stress-rating tool for caregivers with and without the use of the device. User satisfaction was evaluated using the usefulness, satisfaction, and ease of use questionnaire. There was a significant reduction in transfer-time with manual transfers compared to STurDi-assisted transfers [mean (SD) = 48.39 (13.98) vs. 36.23 (10.96); p ≤ 0.001]. The physical stress rating was significantly lower in STurDi-aided transfers compared to manual transfers, shoulder [median (interquartile range) = 0 (1) vs. 4 (3); p = 0.001], upper back [0 (0) vs. 5 (4); p = 0.001], lower back [0 (1) vs. 5 (3), p = 0.001], whole body [1 (2) vs. 4 (3), p = 0.001], and knee [0 (1) vs. 1 (4), p = 0.001]. In addition, majority of patients and caregivers definitely or strongly agreed that the device was useful, saved time, and was easy to use. We have therefore demonstrated in a setting where manual handling was commonly performed that a low-cost mechanical transfer device reduced caregiver strain and was well received by older patients and caregivers.
Fulltext New oral anticoagulants for venous thromboembolism (VTE) prophylaxis

Liew NC, Sim KH, Ng SC, Suhail A, Premchandran N

Med J Malaysia, 2011 Aug;66(3):278-80; quiz 281.
PMID: 22111463 MyJurnal

Venous thromboembolism is a rising concern in Asia especially among patients after surgery where this complication is readily preventable. Despite the availability of several treatment options, the acceptance of prophylaxis and usage of these methods remain low. A possible explanation to this behavior is the limitations attached to the available treatment options: narrow therapeutic window of warfarin and parenteral administration of low molecular weight as well as unfractionated heparins. Newer agents have been researched and introduced to overcome these limitations in the hope of improving the adaptation towards post surgical thromboprophylaxis. Dabigatran and rivaroxaban are two such new agents that are promising in view of efficacy and ease of administration.
Fulltext Familial hemophagocytic lymphohistiocytosis in two brothers

Gan GG, Eow GI, Teh A, Ng SC, Sangkar JV

Med J Malaysia, 2004 Mar;59(1):100-2.
PMID: 15535343

Familial hemophagocytic lymphohistiocytosis is a disorder which presents with fever, pancytopenia, liver dysfunction and also an increase in non-malignant histiocytes with prominent hemophagocytosis in various organs. It is usually difficult to distinguish from other hemophagocytic syndrome in the absence of family history. It rarely manifests in adults. Chemotherapy is usually indicated. Here, we report the occurrence of this disorder in two brothers in their twenties.
Fulltext Balloon endometrial thermoablation--an alternative management of adenomyosis with menorrhagia and dysmenorrhoea

Chan CLK, Annapoorna V, Roy AC, Ng SC

Med J Malaysia, 2001 Sep;56(3):370-3.
PMID: 11732085

A 45 years old Chinese housewife presented with menorrhagia and dysmenorrhoea due to adenomyosis failed to respond to various medical treatments. She was treated with balloon thermoablation. The total menstrual blood loss (MBL) decreased from 96.94 ml before to 37.57 ml, six months after thermoablation. The pictorial blood loss chart (PBLC) showed similar decrease in blood loss. Dysmenorrhoea was also cured. At three year follow up, there was no recurrence. This is the first report which shows thermoablation decreases MBL objectively and can be tried to treat adenomyosis.
Fulltext Multiple myeloma in the University Hospital: a retrospective study of biodata, clinical, laboratory and radiological profiles, 1980-1987

Wong KT, Ng SC, Kuperan P, Yap SF, Menaka N, Bosco J

Med J Malaysia, 1990 Jun;45(2):136-43.
PMID: 2152018

A retrospective study of 37 cases of multiple myeloma admitted from 1980 to 1987 to the University Hospital Kuala Lumpur, Malaysia, was carried out to analyse the biodata, clinical presentation, laboratory and radiological profiles. The cases were selected after they had satisfied preset diagnostic criteria. The mean age was 60 years. There was no sex or ethnic preponderance. The most common symptom was bone pain. Pallor was detected in 73% of the patients. Haemoglobin was less than 120 g/L in 95%, and ESR was greater than 100 mm/hr in 70% of cases. Bone marrow and trephine biopsies were diagnostically important. Hypercalcaemia occurred in seven cases out of which three were IgA myelomas. Either serum creatinine or blood urea was raised in nearly 50% of cases. The most common heavy chain paraprotein was IgG while Kappa light chain was the commoner light chain type. 86% of cases had osteolytic lesions. These findings are, in general, similar to those of larger studies on multiple myeloma.

Study site: University Malaya Medical Centre (UMMC)
Fulltext In vitro fertilization outcome in severe ovarian hyperstimulation syndrome: An age-matched contemporaneous control study

Ng SP, Rashid Mr Z, Kumar J, Ng SC

Reprod. Med. Biol., 2005 Sep;4(3):207-211.
PMID: 29699224 DOI: 10.1111/j.1447-0578.2005.00107.x

Aim: Ovarian hyperstimulation syndrome (OHSS) is a potentially life-threatening, iatrogenic complication of assisted reproduction and has been associated with poor in vitro fertilization outcome. The aim of the present study was to evaluate the pregnancy rate and outcome following severe OHSS, at a single center over a three-year period. Methods: The incidence of severe OHSS at the IVF Center, National University of Singapore, in Singapore, was 4% (48 cases over 1200 cycles) during the period of 1997-2000. The present retrospective study compared 48 cases of severe OHSS to 144 age-matched, contemporaneous controls without OHSS. Results: The total gonadotropin required for severe OHSS group was found to be lower than for that of controls (2664.06 ± 768.29 IU vs 3349.58 ± 2003.73 IU), although duration of stimulation was similar. The OHSS group was associated with a fivefold increase (OR 5.293, 95% CI: 2.116-13.238) in pregnancy rate compared to controls (87.5% vs 56.9%; P 0.05) and miscarriage rates (14% vs 7.3%; P > 0.05) between the groups. Conclusion: Severe OHSS at our center were mostly late onset. The pregnancy rate was significantly higher, but multiple pregnancy and miscarriage rates were not significantly increased when compared to the age-matched contemporaneous controls. (Reprod Med Biol 2005; 4: 207-211).
Fulltext Temporal and Spatial Dynamics of EEG Features in Female College Students with Subclinical Depression

Zhao S, Ng SC, Khoo S, Chi A

Int J Environ Res Public Health, 2022 Feb 04;19(3).
PMID: 35162800 DOI: 10.3390/ijerph19031778

Synchronization of the dynamic processes in structural networks connect the brain across a wide range of temporal and spatial scales, creating a dynamic and complex functional network. Microstate and omega complexity are two reference-free electroencephalography (EEG) measures that can represent the temporal and spatial complexities of EEG data. Few studies have focused on potential brain spatiotemporal dynamics in the early stages of depression to use as an early screening feature for depression. Thus, this study aimed to explore large-scale brain network dynamics of individuals both with and without subclinical depression, from the perspective of temporal and spatial dimensions and to input them as features into a machine learning framework for the automatic diagnosis of early-stage depression. To achieve this, spatio-temporal dynamics of rest-state EEG signals in female college students (n = 40) with and without (n = 38) subclinical depression were analyzed using EEG microstate and omega complexity analysis. Then, based on differential features of EEGs between the two groups, a support vector machine was utilized to compare performances of spatio-temporal features and single features in the classification of early depression. Microstate results showed that the occurrence rate of microstate class B was significantly higher in the group with subclinical depression when compared with the group without. Moreover, the duration and contribution of microstate class C in the subclinical group were both significantly lower than in the group without subclinical depression. Omega complexity results showed that the global omega complexity of β-2 and γ band was significantly lower for the subclinical depression group compared with the other group (p < 0.05). In addition, the anterior and posterior regional omega complexities were lower for the subclinical depression group compared to the comparison group in α-1, β-2 and γ bands. It was found that AUC of 81% for the differential indicators of EEG microstates and omega complexity was deemed better than a single index for predicting subclinical depression. Thus, since temporal and spatial complexity of EEG signals were manifestly altered in female college students with subclinical depression, it is possible that this characteristic could be adopted as an early auxiliary diagnostic indicator of depression.
Fulltext Multimodality registration of two-dimensional echocardiography and cardiac CT for mitral valve diagnosis and surgical planning

Khalil A, Faisal A, Ng SC, Liew YM, Lai KW

J Med Imaging (Bellingham), 2017 Jul;4(3):037001.
PMID: 28840172 DOI: 10.1117/1.JMI.4.3.037001

A registration method to fuse two-dimensional (2-D) echocardiography images with cardiac computed tomography (CT) volume is presented. The method consists of two major procedures: temporal and spatial registrations. In temporal registration, the echocardiography frames at similar cardiac phases as the CT volume were interpolated based on electrocardiogram signal information, and the noise of the echocardiography image was reduced using the speckle reducing anisotropic diffusion technique. For spatial registration, an intensity-based normalized mutual information method was applied with a pattern search optimization algorithm to produce an interpolated cardiac CT image. The proposed registration framework does not require optical tracking information. Dice coefficient and Hausdorff distance for the left atrium assessments were [Formula: see text] and [Formula: see text], respectively; for left ventricle, they were [Formula: see text] and [Formula: see text], respectively. There was no significant difference in the mitral valve annulus diameter measurement between the manually and automatically registered CT images. The transformation parameters showed small deviations ([Formula: see text] deviation in translation and [Formula: see text] for rotation) between manual and automatic registrations. The proposed method aids the physician in diagnosing mitral valve disease as well as provides surgical guidance during the treatment procedure.
2D to 3D fusion of echocardiography and cardiac CT for TAVR and TAVI image guidance

Khalil A, Faisal A, Lai KW, Ng SC, Liew YM

Med Biol Eng Comput, 2017 Aug;55(8):1317-1326.
PMID: 27830464 DOI: 10.1007/s11517-016-1594-6

This study proposed a registration framework to fuse 2D echocardiography images of the aortic valve with preoperative cardiac CT volume. The registration facilitates the fusion of CT and echocardiography to aid the diagnosis of aortic valve diseases and provide surgical guidance during transcatheter aortic valve replacement and implantation. The image registration framework consists of two major steps: temporal synchronization and spatial registration. Temporal synchronization allows time stamping of echocardiography time series data to identify frames that are at similar cardiac phase as the CT volume. Spatial registration is an intensity-based normalized mutual information method applied with pattern search optimization algorithm to produce an interpolated cardiac CT image that matches the echocardiography image. Our proposed registration method has been applied on the short-axis "Mercedes Benz" sign view of the aortic valve and long-axis parasternal view of echocardiography images from ten patients. The accuracy of our fully automated registration method was 0.81 ± 0.08 and 1.30 ± 0.13 mm in terms of Dice coefficient and Hausdorff distance for short-axis aortic valve view registration, whereas for long-axis parasternal view registration it was 0.79 ± 0.02 and 1.19 ± 0.11 mm, respectively. This accuracy is comparable to gold standard manual registration by expert. There was no significant difference in aortic annulus diameter measurement between the automatically and manually registered CT images. Without the use of optical tracking, we have shown the applicability of this technique for effective fusion of echocardiography with preoperative CT volume to potentially facilitate catheter-based surgery.
Knee cartilage segmentation and thickness computation from ultrasound images

Faisal A, Ng SC, Goh SL, Lai KW

Med Biol Eng Comput, 2018 Apr;56(4):657-669.
PMID: 28849317 DOI: 10.1007/s11517-017-1710-2

Quantitative thickness computation of knee cartilage in ultrasound images requires segmentation of a monotonous hypoechoic band between the soft tissue-cartilage interface and the cartilage-bone interface. Speckle noise and intensity bias captured in the ultrasound images often complicates the segmentation task. This paper presents knee cartilage segmentation using locally statistical level set method (LSLSM) and thickness computation using normal distance. Comparison on several level set methods in the attempt of segmenting the knee cartilage shows that LSLSM yields a more satisfactory result. When LSLSM was applied to 80 datasets, the qualitative segmentation assessment indicates a substantial agreement with Cohen's κ coefficient of 0.73. The quantitative validation metrics of Dice similarity coefficient and Hausdorff distance have average values of 0.91 ± 0.01 and 6.21 ± 0.59 pixels, respectively. These satisfactory segmentation results are making the true thickness between two interfaces of the cartilage possible to be computed based on the segmented images. The measured cartilage thickness ranged from 1.35 to 2.42 mm with an average value of 1.97 ± 0.11 mm, reflecting the robustness of the segmentation algorithm to various cartilage thickness. These results indicate a potential application of the methods described for assessment of cartilage degeneration where changes in the cartilage thickness can be quantified over time by comparing the true thickness at a certain time interval.
Fulltext An Overview on Image Registration Techniques for Cardiac Diagnosis and Treatment

Khalil A, Ng SC, Liew YM, Lai KW

Cardiol Res Pract, 2018;2018:1437125.
PMID: 30159169 DOI: 10.1155/2018/1437125

Image registration has been used for a wide variety of tasks within cardiovascular imaging. This study aims to provide an overview of the existing image registration methods to assist researchers and impart valuable resource for studying the existing methods or developing new methods and evaluation strategies for cardiac image registration. For the cardiac diagnosis and treatment strategy, image registration and fusion can provide complementary information to the physician by using the integrated image from these two modalities. This review also contains a description of various imaging techniques to provide an appreciation of the problems associated with implementing image registration, particularly for cardiac pathology intervention and treatments.
Robust aortic valve non-opening detection for different cardiac conditions

Ooi HL, Ng SC, Lim E, Salamonsen RF, Avolio AP, Lovell NH

Artif Organs, 2014 Mar;38(3):E57-67.
PMID: 24422872 DOI: 10.1111/aor.12220

In recent years, extensive studies have been conducted in the area of pumping state detection for implantable rotary blood pumps. However, limited studies have focused on automatically identifying the aortic valve non-opening (ANO) state despite its importance in the development of control algorithms aiming for myocardial recovery. In the present study, we investigated the performance of 14 ANO indices derived from the pump speed waveform using four different types of classifiers, including linear discriminant analysis, logistic regression, back propagation neural network, and k-nearest neighbors (KNN). Experimental measurements from four greyhounds, which take into consideration the variations in cardiac contractility, systemic vascular resistance, and total blood volume were used. By having only two indices, (i) the root mean square value, and (ii) the standard deviation, we were able to achieve an accuracy of 92.8% with the KNN classifier. Further increase of the number of indices to five for the KNN classifier increases the overall accuracy to 94.6%.
Evaluation of suction detection during different pumping states in an implantable rotary blood pump

Ng SC, Lim E, Mason DG, Avolio AP, Lovell NH

Artif Organs, 2013 Aug;37(8):E145-54.
PMID: 23635073 DOI: 10.1111/aor.12079

In recent times, the problem of noninvasive suction detection for implantable rotary blood pumps has attracted substantial research interest. Here, we compare the performance of various suction indices for different types of suction and non-suction events based on pump speed irregularity. A total of 171 different indices that consist of previously proposed as well as newly introduced suction indices are tested using regularized logistic regression. These indices can be classified as amplitude based (derived from the mean, maximum, and minimum values of a cycle), duration based (derived from the duration of a cycle), gradient based (derived from the first order as well as higher order differences) and frequency based (derived from the power spectral density). The non-suction event data consists of ventricular ejection with or without arrhythmia and intermittent and continuous non-opening of the aortic valve. The suction event data consists of partial ventricular collapse that occurs intermittently as well as continuously with or without arrhythmia. In addition, we also attempted to minimize the usage of multiple indices by applying the sequential forward floating selection method to find which combination of indices gives the best performance. In general, the amplitude-based and gradient-based indices performed quite well while the duration-based and frequency-based indices performed poorly. By having only two indices ([i] the maximum gradient change in positive slope; and [ii] the standard deviation of the maximum value in a cycle), we were able to achieve a sensitivity of 98.9% and a specificity of 99.7%.
Fulltext Coronary stents in the management of coronary artery disease review of first 100 stents

Ng SC, Sawatt C, Foo LK, Hitam O, Khor PG, Lee YK

Med J Malaysia, 1996 Mar;51(1):75-9.
PMID: 10967983

This is a review of the first 100 coronary stents implanted for the indications of PTCA restenosis, acute or threatened closure and De Novo lesions. The success rates were high and complications rates were low. Subacute stent thrombosis rates were low and stenting for De Novo lesions in > 3.0 mm arteries provide the best short and long term results. Six months restenosis rate was low. Stent assisted high pressure balloon angioplasty is an important advance.

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