X-ray based radiological procedure statistics and trend in Malaysia for 1990-1994 is reported; this information allows comparisons to be made with the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) Report. Additionally it is essential information for health care planners and providers. Malaysia is categorised as a health care level II country based on the UNSCEAR definition. In 1994, the number of physicians, radiologists, x-ray units and x-ray examinations per 1000 population was 0.45, 0.005, 0.065 and 183 respectively. 3.6 million x-ray examinations were performed in 1994, with chest radiography being the commonest study (63%). Information on x-ray examinations, number of hospitals and x-ray units is reported for the Ministry of Health, private practice and teaching hospitals. Examination frequency increased in computed tomography (161%), cardiac procedures (190%), and mammography (240%); while a decrease in barium studies (-23%), cholecystography (-36%), and intravenous urography (-51%) was noted. There is a potential and need to expand and upgrade radiological services.
The purpose of the results section is to present the main data collected and the observations made during the research. It provides interpretation of the analysed data and does not contain details on the methods, materials or discussion. The first step in writing the results section is to review the analysed data and determine which results to present. This can be done by deciding which results are relevant to the question(s) presented in the introduction, and may be supplemented by illustrative tables and figures. The results section guides the reader through the questions investigated in the study and sets the stage for the discussion in the next section.
When writing scientific papers to share their research findings with their peers, it is not enough for researchers to just communicate the results of their study; it is equally important to explain the process by which they arrived at their results, so that the study can be replicated to validate the observations. The materials and methods section is used to describe the experimental design and provide sufficient details so that a competent colleague can repeat the experiment. A good materials and methods section will enable readers to evaluate the research performed and replicate the study, if necessary.
The discussion section comprises the last component in the IMRAD system. The purpose of this section is to provide the interpretation of the results obtained, explain the implications of the findings, state study limitations and make suggestions for future research. This is a critical part of the scientific paper, as it places the particular study within the broader context of how the research contributes to improving diagnosis, treatment or patient care.
A technical note is a short article giving a brief description of a specific development, technique or procedure, or it may describe a modification of an existing technique, procedure or device applicable to medicine. The technique, procedure or device described should have practical value and should contribute to clinical diagnosis or management. It could also present a software tool, or an experimental or computational method. Technical notes are variously referred to as technical innovations or technical developments. The main criteria for publication will be the novelty of concepts involved, the validity of the technique and its potential for clinical applications.
Evidence-based medicine (EBM) aims to combine the best available scientific evidence with clinical experience and individual judgment of patient needs. In the hierarchy of scientific evidence, systematic reviews (along with meta-analyses) occupy the highest levels in terms of the quality of evidence. A systematic review is the process of searching, selecting, appraising, synthesising and reporting clinical evidence on a particular question or topic. It is currently considered the best, least biased and most rational way to organise, gather, evaluate and integrate scientific evidence from the rapidly-changing medical and healthcare literature. Systematic reviews could be used to present current concepts or serve as review articles and replace the traditional expert opinion or narrative review. This article explains the structure and content of a systematic review.
A case report is a description of a single case with unique features. This includes a previously-unreported clinical condition, previously-unreported observation of a recognised disease, unique use of imaging or diagnostic test to reveal a disease, previously-unreported treatment in a recognised disease, or previously-unreported complication of a procedure. Case reports should be short and focused, with a limited number of figures and references. The structure of a case report usually comprises a short unstructured (or no) abstract, brief (or no) introduction, succinct but comprehensive report of the case, and to-the-point discussion.
Wavelet-based image coding algorithms (lossy and lossless) use a fixed perfect reconstruction filter-bank built into the algorithm for coding and decoding of images. However, no systematic study has been performed to evaluate the coding performance of wavelet filters on medical images. We evaluated the best types of filters suitable for medical images in providing low bit rate and low computational complexity. In this study a variety of wavelet filters are used to compress and decompress computed tomography (CT) brain and abdomen images. We applied two-dimensional wavelet decomposition, quantization and reconstruction using several families of filter banks to a set of CT images. Discreet Wavelet Transform (DWT), which provides efficient framework of multi-resolution frequency was used. Compression was accomplished by applying threshold values to the wavelet coefficients. The statistical indices such as mean square error (MSE), maximum absolute error (MAE) and peak signal-to-noise ratio (PSNR) were used to quantify the effect of wavelet compression of selected images. The code was written using the wavelet and image processing toolbox of the MATLAB (version 6.1). This results show that no specific wavelet filter performs uniformly better than others except for the case of Daubechies and bi-orthogonal filters which are the best among all. MAE values achieved by these filters were 5 x 10(-14) to 12 x 10(-14) for both CT brain and abdomen images at different decomposition levels. This indicated that using these filters a very small error (approximately 7 x 10(-14)) can be achieved between original and the filtered image. The PSNR values obtained were higher for the brain than the abdomen images. For both the lossy and lossless compression, the 'most appropriate' wavelet filter should be chosen adaptively depending on the statistical properties of the image being coded to achieve higher compression ratio.
Dengue, an important mosquito-borne flavivirus infection, is endemic in Southeast Asia. We describe two mothers who had acute dengue 4 and 8 days before the births of their infants. One mother had worsening of her proteinuric pregnancy-induced hypertension, liver dysfunction, and coagulopathy and required multiple transfusions of whole blood, platelets, and fresh frozen plasma. Her male infant was ill at birth, developed respiratory distress and a large uncontrollable left intracerebral hemorrhage, and died of multiorgan failure on day 6 of life. Dengue virus type 2 was isolated from the infant's blood, and IgM antibody specific to dengue virus was detected in the mother's blood. The second mother had a milder clinical course; she gave birth to a female infant who was thrombocytopenic at birth and had an uneventful hospitalization. Dengue virus type 2 was recovered from the mother's blood, and IgM antibody specific to dengue virus was detected in the infant's blood. This report highlights not only the apparently rare occurrence of vertical transmission of dengue virus in humans but also the potential risk of death for infected neonates.
Peripheral blood-derived inflammation-based scores such as the neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) have recently been proposed as prognostic markers in solid tumours. Although evidence to support these markers as unfavourable prognostic factors is more compelling in gastrointestinal cancers, very little is known of their impact on breast cancer. We investigated the association between the NLR and PLR, and overall survival after breast cancer.
The utility of a phantom material, based on SMR(L) [Standard Malaysian Rubber] grade natural rubber and a formulation used for the proprietary rubber phantom-material, Temex, has been examined for the 1-MeV photon-Measurement has also been performed with 60-keV photons using the radionuclide 241Am. At photon-therapy energy levels the measured response, when compared with tabulated central-axis percentage depth doses for the defined measuring conditions, produces everywhere (in the range 1-19 cm depth) better than 2% deviation. The favourable measured response characteristics combined with the ease of processing and casting the phantom material provide the basis for useful radiotherapy machine calibration and anthropomorphic dosimetry measurements. The measured mass-attenuation coefficient, at 60keV, of 0.204 cm2 g-1 (+/- 3%) is in close agreement with tabulated values for water (0.2055 cm2 g-1).
A prospective study was carried out at the University Hospital, Kuala Lumpur to determine the cervical carriage rate of Ureaplasma urealyticum and Mycoplasma hominis among healthy pregnant women at delivery and the incidence of nasopharyngeal colonisation among their infants.
Granular cell ameloblastoma (GCA) is a well recognized variant of follicular ameloblastoma with extensive granular cell change. In contrast, plexiform granular cell odontogenic tumor (PGCOT) is a rare and recently described lesion characterized histologically by a monophasic plexiform pattern of granular cells. In this paper, two cases of an unusual granular cell odontogenic tumor exhibiting combined features of these two entities are described along with their immunohistochemical characteristics. The granular cells of both the GCA and PGCOT areas showed similar patterns of expression for keratin and S-100, which differed from those of typical ameloblastoma. No reactivity for desmin or vimentin was noted. The histomorphologic and immunohistochemical features of these hybrid tumors suggest that the granular cells present have a common origin, most probably the odontogenic epithelium.
This paper sets out guidelines for managing radiation exposure incidents involving patients in diagnostic and interventional radiology. The work is based on collation of experiences from representatives of international and national organizations for radiologists, medical physicists, radiographers, regulators, and equipment manufacturers, derived from an International Atomic Energy Agency Technical Meeting. More serious overexposures can result in skin doses high enough to produce tissue reactions, in interventional procedures and computed tomography, most notably from perfusion studies. A major factor involved has been deficiencies in training of staff in operation of equipment and optimization techniques. The use of checklists and time outs before procedures commence, and dose alerts when critical levels are reached during procedures can provide safeguards to reduce risks of these effects occurring. However, unintended and accidental overexposures resulting in relatively small additional doses can take place in any diagnostic or interventional X-ray procedure and it is important to learn from errors that occur, as these may lead to increased risks of stochastic effects. Such events may involve the wrong examinations, procedural errors, or equipment faults. Guidance is given on prevention, investigation and dose calculation for radiology exposure incidents within healthcare facilities. Responsibilities should be clearly set out in formal policies, and procedures should be in place to ensure that root causes are identified and deficiencies addressed. When an overexposure of a patient or an unintended exposure of a foetus occurs, the foetal, organ, skin and/or effective dose may be estimated from exposure data. When doses are very low, generic values for the examination may be sufficient, but a full assessment of doses to all exposed organs and tissues may sometimes be required. The use of general terminology to describe risks from stochastic effects is recommended rather than calculation of numerical values, as these are misleading when applied to individuals.
Renal cell carcinoma (RCC) generally has a poor prognosis because of late diagnosis and metastasis. We have previously described decreased tumour necrosis factor receptor-associated factor-1 (TRAF-1) in RCC compared with paired normal kidney in a patient cohort in Australia. In the present study, TRAF-1 expression in clear cell RCC (ccRCC) and normal kidney was again compared, but in a cohort from University Malaya Medical Centre. Serum TRAF-1 was also evaluated in RCC and normal samples.Immunohistochemistry with automated batch staining and Aperio ImageScope morphometry was used to compare TRAF-1 in 61 ccRCC with paired normal kidney tissue. Serum from 15 newly diagnosed and untreated ccRCC and 15 healthy people was tested for TRAF-1 using ELISA.In this cohort, TRAF-1 was highly expressed in proximal tubular epithelium of normal kidney, and significantly decreased in ccRCC tissue (p
Tsukamurella spp. are a rare but important cause of intravascular catheter-related bacteremia in immunocompromised patients. The organism is an aerobic, Gram-positive, weakly acid-fast bacillus that is difficult to differentiate using standard laboratory methods from other aerobic actinomycetales such as Nocardia spp., Rhododoccus spp., Gordonia spp., and the rapid growing Mycobacterium spp. We report a case of Tsukamurella tyrosinosolvens catheter-related bacteremia in a 51-year-old haematology patient who responded to treatment with imipenem and subsequent line removal. 16srRNA sequencing allowed for the prompt identification of this organism.
Available data for obstetric care in the University Malaya Medical Centre, Kuala Lumpur from 1987 to 1999 were reviewed. Despite incomplete data, we were able to determine fairly well the practice of obstetric anaesthesia and analgesia in the unit, and the changes over the years. There was a decline in the use of general anaesthesia for both elective and emergency caesarean sections from 41.3% and 69.4% respectively in 1995 to 21.6% and 26.9% respectively in 1999. By 1999, regional anaesthesia had become the most common method of anaesthesia administered in both elective (14.3% epidural and 63.5% spinal) and emergency (30.2% epidural and 42.6% spinal) caesarean sections. The percentage of patients delivering vaginally who received epidural analgesia appeared to have stabilised at about 8 to 9% in the last few years, with a gradual decline in the total instrumental delivery rate from a high of about 12% to the pre-epidural rate of 7%.
Radiochromic and radiographic films are widely used for radiation dosimetry due to the advantage of high spatial resolution and two-dimensional dose measurement. Different types of scanners, including various models of flatbed scanners, have been used as part of the dosimetry readout procedure. This paper focuses on the characterization of the EBT2 film response in combination with a Microtek ScanMaker 9800XL scanner and the subsequent use in the dosimetric verification of a 3D conformal radiotherapy treatment. The film reproducibility and scanner uniformity of the Microtek ScanMaker 9800XL was studied. A three-field 3D conformal radiotherapy treatment was planned on an anthropomorphic phantom and EBT2 film measurements were carried out to verify the treatment. The interfilm reproducibility was found to be 0.25%. Over a period of three months, the films darkened by 1%. The scanner reproducibility was ± 2% and a nonuniformity was ±1.9% along the direction perpendicular to the scan direction. EBT2 measurements showed an underdose of 6.2% at high-dose region compared to TPS predicted dose. This may be due to the inability of the treatment planning system to predict the correct dose distribution in the presence of tissue inhomogeneities and the uncertainty of the scanner reproducibility and uniformity. The use of EBT2 film in conjunction with the axial CT image of the anthropomorphic phantom allows the evaluation of the anatomical location of dose discrepancies between the EBT2 measured dose distribution and TPS predicted dose distribution.
This document is the first of a series of policy statements being issued by the Asia-Oceania Federation of Organizations for Medical Physics (AFOMP). The document was developed by the AFOMP Professional Development Committee (PDC) and was endorsed for official release by AFOMP Council in 2006. The main purpose of the document was to give guidance to AFOMP member organizations on the role and responsibilities of clinical medical physicists. A definition of clinical medical physicist has also been provided. This document discusses the following topics: professional aspects of education and training; responsibilities of the clinical medical physicist; status and organization of the clinical medical physics service and the need for clinical medical physics service.