Displaying publications 41 - 60 of 1046 in total

Abstract:
Sort:
  1. Abu Hassan H, Suppiah S
    Ann Acad Med Singap, 2016 Dec;45(12):567-568.
    PMID: 28062887
    Matched MeSH terms: Tomography, X-Ray Computed
  2. Abubakar A, Shaukat SI, Karim NKA, Kassim MZ, Lim SY, Appalanaido GK, et al.
    Phys Eng Sci Med, 2023 Mar;46(1):339-352.
    PMID: 36847965 DOI: 10.1007/s13246-023-01227-6
    Deep inspiration breath-hold radiotherapy (DIBH-RT) reduces cardiac dose by over 50%. However, poor breath-hold reproducibility could result in target miss which compromises the treatment success. This study aimed to benchmark the accuracy of a Time-of-Flight (ToF) imaging system for monitoring breath-hold during DIBH-RT. The accuracy of an Argos P330 3D ToF camera (Bluetechnix, Austria) was evaluated for patient setup verification and intra-fraction monitoring among 13 DIBH-RT left breast cancer patients. The ToF imaging was performed simultaneously with in-room cone beam computed tomography (CBCT) and electronic portal imaging device (EPID) imaging systems during patient setup and treatment delivery, respectively. Patient surface depths (PSD) during setup were extracted from the ToF and the CBCT images during free breathing and DIBH using MATLAB (MathWorks, Natick, MA) and the chest surface displacement were compared. The mean difference ± standard deviation, correlation coefficient, and limit of agreement between the CBCT and ToF were 2.88 ± 5.89 mm, 0.92, and - 7.36, 1.60 mm, respectively. The breath-hold stability and reproducibility were estimated using the central lung depth extracted from the EPID images during treatment and compared with the PSD from the ToF. The average correlation between ToF and EPID was - 0.84. The average intra-field reproducibility for all the fields was within 2.70 mm. The average intra-fraction reproducibility and stability were 3.74 mm, and 0.80 mm, respectively. The study demonstrated the feasibility of using ToF camera for monitoring breath-hold during DIBH-RT and shows good breath-hold reproducibility and stability during the treatment delivery.
    Matched MeSH terms: Tomography, X-Ray Computed
  3. Acharya UR, Hagiwara Y, Sudarshan VK, Chan WY, Ng KH
    J Zhejiang Univ Sci B, 2018 1 9;19(1):6-24.
    PMID: 29308604 DOI: 10.1631/jzus.B1700260
    Radiology (imaging) and imaging-guided interventions, which provide multi-parametric morphologic and functional information, are playing an increasingly significant role in precision medicine. Radiologists are trained to understand the imaging phenotypes, transcribe those observations (phenotypes) to correlate with underlying diseases and to characterize the images. However, in order to understand and characterize the molecular phenotype (to obtain genomic information) of solid heterogeneous tumours, the advanced sequencing of those tissues using biopsy is required. Thus, radiologists image the tissues from various views and angles in order to have the complete image phenotypes, thereby acquiring a huge amount of data. Deriving meaningful details from all these radiological data becomes challenging and raises the big data issues. Therefore, interest in the application of radiomics has been growing in recent years as it has the potential to provide significant interpretive and predictive information for decision support. Radiomics is a combination of conventional computer-aided diagnosis, deep learning methods, and human skills, and thus can be used for quantitative characterization of tumour phenotypes. This paper discusses the overview of radiomics workflow, the results of various radiomics-based studies conducted using various radiological images such as computed tomography (CT), magnetic resonance imaging (MRI), and positron-emission tomography (PET), the challenges we are facing, and the potential contribution of radiomics towards precision medicine.
    Matched MeSH terms: Tomography, X-Ray Computed
  4. Achuthan A, Rajeswari M, Ramachandram D, Aziz ME, Shuaib IL
    Comput Biol Med, 2010 Jul;40(7):608-20.
    PMID: 20541182 DOI: 10.1016/j.compbiomed.2010.04.005
    This paper introduces an approach to perform segmentation of regions in computed tomography (CT) images that exhibit intra-region intensity variations and at the same time have similar intensity distributions with surrounding/adjacent regions. In this work, we adapt a feature computed from wavelet transform called wavelet energy to represent the region information. The wavelet energy is embedded into a level set model to formulate the segmentation model called wavelet energy-guided level set-based active contour (WELSAC). The WELSAC model is evaluated using several synthetic and CT images focusing on tumour cases, which contain regions demonstrating the characteristics of intra-region intensity variations and having high similarity in intensity distributions with the adjacent regions. The obtained results show that the proposed WELSAC model is able to segment regions of interest in close correspondence with the manual delineation provided by the medical experts and to provide a solution for tumour detection.
    Matched MeSH terms: Tomography, X-Ray Computed/methods*
  5. Adeshina AM, Hashim R, Khalid NE
    Interdiscip Sci, 2014 Sep;6(3):222-34.
    PMID: 25205500 DOI: 10.1007/s12539-013-0204-7
    Hepatocellular Carcinoma is the most common type of liver cancer having a strong relation with cirrhosis. Undoubtedly, cirrhosis may be caused by the virus infection of hepatitis B (HBV) and hepatitis C (HBC) or through alchoholism. However, even when cirrhosis has not been developed, patients with hepatitis viral infections are still at the risk of liver cancer. Apparently, among the numerous medical imaging techniques, Computed Tomography (CT) is the best in defining liver tumor borders. Unfortunately, these imaging techniques, including the CT procedures, usually rely on an appended application to reconstruct the generated 2-D slices to 3-D model. This may involve high performance computation, may be time-consuming or costly. Moreover, even with the outstanding performances of CT in defining the liver tumor boundaries, contrast between tumor tissues and the surrounding liver parenchyma is too low in CT slices. With such a close proxity in the tumor and the surrounding liver tissues, accurate characterization of liver tumor is a challenge. Previously, algorithms were developed to reveal abnormalities in brain's MRI datasets and CT abdominal pelvic, however, introducing a framework that could accurately characterize liver tumor and its surrounding tissues in CT datasets would go a long way in contributing to medical diagnosis and therapy planning of Hepatocellular Carcinoma. This paper proposes an Hepatocellular Carcinoma framework by extending the functionalities of SurLens Visualization System with an automatic liver tumor localization technique using Compute Unified Device Architecture (CUDA). The study was evaluated with liver CT datasets from the Imaging Science and Information Systems (ISIS) Center, the Georgetown University Medical Center. Significantly, visualization of liver CT datasets and the localization of the entangled tumor was achieved without prior datasets segmentation. Interestingly, the framework achieved remarkably good processing speed at a reasonably cheaper cost with an immediate reconstruction of the datasets and mapping of the tumor tissues within the surrounding liver parenchyma.
    Matched MeSH terms: Tomography, X-Ray Computed
  6. Adeshina AM, Hashim R, Khalid NE, Abidin SZ
    Interdiscip Sci, 2013 Mar;5(1):23-36.
    PMID: 23605637 DOI: 10.1007/s12539-013-0155-z
    In the medical diagnosis and treatment planning, radiologists and surgeons rely heavily on the slices produced by medical imaging devices. Unfortunately, these image scanners could only present the 3-D human anatomical structure in 2-D. Traditionally, this requires medical professional concerned to study and analyze the 2-D images based on their expert experience. This is tedious, time consuming and prone to error; expecially when certain features are occluding the desired region of interest. Reconstruction procedures was earlier proposed to handle such situation. However, 3-D reconstruction system requires high performance computation and longer processing time. Integrating efficient reconstruction system into clinical procedures involves high resulting cost. Previously, brain's blood vessels reconstruction with MRA was achieved using SurLens Visualization System. However, adapting such system to other image modalities, applicable to the entire human anatomical structures, would be a meaningful contribution towards achieving a resourceful system for medical diagnosis and disease therapy. This paper attempts to adapt SurLens to possible visualisation of abnormalities in human anatomical structures using CT and MR images. The study was evaluated with brain MR images from the department of Surgery, University of North Carolina, United States and CT abdominal pelvic, from the Swedish National Infrastructure for Computing. The MR images contain around 109 datasets each of T1-FLASH, T2-Weighted, DTI and T1-MPRAGE. Significantly, visualization of human anatomical structure was achieved without prior segmentation. SurLens was adapted to visualize and display abnormalities, such as an indication of walderstrom's macroglobulinemia, stroke and penetrating brain injury in the human brain using Magentic Resonance (MR) images. Moreover, possible abnormalities in abdominal pelvic was also visualized using Computed Tomography (CT) slices. The study shows SurLens' functionality as a 3-D Multimodal Visualization System.
    Matched MeSH terms: Tomography, X-Ray Computed/methods*
  7. Adi O, Sum KM, Ahmad AH, Wahab MA, Neri L, Panebianco N
    Ultrasound J, 2020 Aug 12;12(1):37.
    PMID: 32783133 DOI: 10.1186/s13089-020-00186-3
    BACKGROUND: Upper airway injury secondary to blunt neck trauma can lead to upper airway obstruction and potentially cause a life-threatening condition. The most important aspect in the care of laryngeal trauma is to establish a secure airway. Focused airway ultrasound enables recognition of important upper airway structures, offers early opportunity to identify life-threatening upper airway injury, and allows assessment of the extent of injury. This information that can be obtained rapidly at the bedside has the potential to facilitate rapid intervention.

    CASE PRESENTATION: We report a case series that illustrate the diagnostic value of focused airway ultrasound in the diagnosis of laryngeal trauma in patients presenting with blunt neck injury.

    CONCLUSION: Early recognition, appropriate triaging, accurate airway evaluation, and prompt management of such injuries are essential. In this case series, we introduce the potential role of focused airway ultrasound in suspected laryngeal trauma, and the correlation of these exam findings with that of computed tomography (CT) scanning, based on the Schaefer classification of laryngeal injury.

    Matched MeSH terms: Tomography, X-Ray Computed
  8. Affirul CA, Azim IM, Hanafiah H, Nor Azmi K, Rozman Z
    Clin Ter, 2013;164(6):e479-83.
    PMID: 24424226 DOI: 10.7417/CT.2013.1640
    INTRODUCTION: Matrix Metalloproteinase 9 (MMP-9) has been shown to express significantly on organ tissue culture in Abdominal Aortic Aneurysm (AAA) patients. Prior studies have shown the correlation between MMP-9 concentration levels with AAA raising the probability of its usage as a biomarker in AAA disease. However, results of previous studies have been conflicting. The purpose of this study is to identify the correlation between MMP-9 concentration levels with AAA disease and further define the utility as a biomarker for our center population.

    MATERIALS AND METHODS: This is prospective controlled trial. Peripheral venous blood sample is obtained from 20 patients with AAA and 36 normal control subjects. MMP-9 concentration levels were determined by an enzyme-linked immunosorbent assay and compared with subjects abdominal ultrasonography or computed tomography of abdomen.

    RESULTS: Mean (± SE) MMP-9 was 23.94 ± 0.60 ng/mL in normal control subjects and 21.39 ± 1.03 ng/mL in patients with AAAs (p ← 0.05 versus normal control subjects). MMP-9 correlate significantly with AAA (p=0.004). There was no correlation of MMP-9 levels with age, gender, or other risk factors. The cutoff point is 12.54 for aorta size <3.0 cm. The sensitivity and specificity of MMP-9 were 60% and 64% respectively.

    CONCLUSIONS: MMP-9 levels correlate significantly with AAA with a cutoff point of 12.54. However, the utility of MMP-9 as a diagnostic test is limited due to low sensitivity and specificity. An elevated MMP-9 has limited use to predict the presence of AAA (positive predictive value: 60%) and a normal MMP-9 level was insufficient to determine the absence of AAA (negative predictive value: 36.1%).

    Matched MeSH terms: Tomography, X-Ray Computed
  9. Ahmad MS, Suardi N, Shukri A, Nik Ab Razak NNA, Oglat AA, Makhamrah O, et al.
    Eur J Radiol Open, 2020;7:100257.
    PMID: 32944594 DOI: 10.1016/j.ejro.2020.100257
    Introduction: Hepatocellular carcinoma (HCC) is one of the most common cancer in the world, and the effectiveness of its treatment lies in its detection in its early stages. The aim of this study is to mimic HCC dynamically through a liver phantom and apply it in multimodality medical imaging techniques including magnetic resonance imaging (MRI), computed tomography (CT), and ultrasound.

    Methods and materials: The phantom is fabricated with two main parts, liver parenchyma and HCC inserts. The liver parenchyma was fabricated by adding 2.5 wt% of agarose powder combined with 2.6 wt% of wax powder while the basic material for the HCC samples was made from polyurethane solution combined with 5 wt% glycerol. Three HCC samples were inserted into the parenchyma by using three cylinders implanted inside the liver parenchyma. An automatic injector is attached to the input side of the cylinders and a suction device connected to the output side of the cylinders. After the phantom was prepared, the contrast materials were injected into the phantom and imaged using MRI, CT, and ultrasound.

    Results: Both HCC samples and liver parenchyma were clearly distinguished using the three imaging modalities: MRI, CT, and ultrasound. Doppler ultrasound was also applied through the HCC samples and the flow pattern was observed through the samples.

    Conclusion: A multimodal dynamic liver phantom, with HCC tumor models have been fabricated. This phantom helps to improve and develop different methods for detecting HCC in its early stages.

    Matched MeSH terms: Tomography, X-Ray Computed
  10. Ahmed O, Yushou Song
    Sains Malaysiana, 2018;47:1883-1890.
    X-ray computed tomography (XCT) became an important instrument for quality assurance in industry products as a
    non-destructive testing tool for inspection, evaluation, analysis and dimensional metrology. Thus, a high-quality image
    is required. Due to the polychromatic nature of X-ray energy in XCT, this leads to errors in attenuation coefficient
    which is generally known as beam hardening artifact. This leads to a distortion or blurring-like cupping and streak in
    the reconstruction images, where a significant decrease in imaging quality is observed. In this paper, recent research
    publications regarding common practical correction methods that were adopted to improve an imaging quality have been
    discussed. It was observed from the discussion and evaluation, that a problem behind beam hardening reduction for the
    multi-materials object, especially in the absence of prior information about X-ray spectrum and material characterizations
    would be a significant research contribution, if the correction could be achieved without the need to perform forward
    projections and multiple reconstructions.
    Matched MeSH terms: Tomography, X-Ray Computed
  11. Aida Abdul Razak, Maniam, T., Hatta Sidi, Shalisah Sharip, Suriati Mohamed Saini
    ASEAN Journal of Psychiatry, 2014;15(1):93-96.
    MyJurnal
    Objective: This case report highlights the challenges in managing Frontal Lobe Syndrome (FLS) in a patient with end-stage renal disease. Methods: This is a case description of a 58 year-old gentleman who presented with behavioural changes: irritability, mood lability, aggression, psychosis, and overfamiliarity. His presenting symptoms were in keeping with (FLS) with positive findings on Computed Tomography (CT) scan of the brain and also neuropsychological assessments. Difficulties arose in attempts to control his aggression without further compromising his renal function. Results: The usage of the commonly used antipsychotics in controlling aggression was restricted in view of the patient’s renal impairment. Augmentation with low dose memantine proved to be beneficial in this case, without causing further deterioration in renal function. Conclusion: The use of memantine to augment the effect of risperidone was observed to be safe and successful in managing the behavioural changes associated with FLS in adults with end-stage renal disease. ASEAN Journal of Psychiatry, Vol. 15 (1): January - June 2014: 93-96.
    Matched MeSH terms: Tomography, X-Ray Computed
  12. Aidayanti MD, Salina H, Gendeh BS, Farah DZ, Faezah MZ
    Med J Malaysia, 2018 08;73(4):249-252.
    PMID: 30121689 MyJurnal
    Endoscopic sinus surgery (ESS) is a standard treatment for rhinosinusitis, which failed optimum medical therapy. Iatrogenic cerebrospinal fluid (CSF) rhinorrhoea can occur during ESS warrants early repair of the leakage. The common sites for CSF leakage are cribriform plate, fovea ethmoidalis, and anterior ethmoid sinuses. We present five cases of iatrogenic CSF rhinorrhoea due to ESS and its management.
    Matched MeSH terms: Tomography, X-Ray Computed
  13. Aizat Sabri I, Yusof MR, Jagwani AV, Fahmy O, Lee CK, Mg-Khairul Asri MA, et al.
    Urologiia, 2022 Dec.
    PMID: 36625624
    We present a rare case of leiomyoma of the urinary bladder that was diagnosed during pregnancy. The case of a 29-year-old woman primigravida at 13 weeks of pregnancy who presented with 6 months history of abdominal swelling which was gradually increasing in size. Computed tomography done revealed a large heterogenous mass(enhancing) with an area of non-enhancing (necrosis) suggestive of malignant ovarian tumor. The histological findings of the surgical specimen confirmed a leiomyoma of the urinary bladder. The clinical presentation, imaging findings, and management of this relatively rare benign tumor are discussed in this case report.
    Matched MeSH terms: Tomography, X-Ray Computed
  14. Ajit Singh V, Earnest Kunasingh D, Haseeb A, Yasin NF
    J Orthop Surg (Hong Kong), 2019 5 30;27(2):2309499019850313.
    PMID: 31138060 DOI: 10.1177/2309499019850313
    PURPOSE: Expandable endoprosthesis allows limb salvage in children with an option to leading a better life. However, the revision rate and implant-related complications impose as a limitation in the skeletal immature. This study investigates the functional outcomes and complications related to expandable endoprosthesis in our centre.

    MATERIALS AND METHODS: Twenty surviving patients with expandable endoprosthesis from 2006 till 2015 were scored using Musculoskeletal Tumour Society (MSTS) outcomes instrument and reviewed retrospectively for range of motion of respected joints, limb length discrepancy, number of surgeries performed, complications and oncological outcomes. Patients with less than 2 years of follow-up were excluded from this study.

    RESULTS: Forty-five percentage patients reached skeletal maturity with initial growing endoprosthesis and 25% of patients were revised to adult modular prosthesis. One hundred fifty-seven surgeries were performed over the 9-year period. The average MSTS score was 90.83%. The mortality rate was 10% within 5 years due to advanced disease. Infection and implant failure rate was 15% each. The event-free survival was 50% and overall survival rate was 90%.

    CONCLUSION: There is no single best option for reconstruction in skeletally immature. This study demonstrates a favourable functional and survival outcome of paediatric patients with expandable endoprosthesis. The excellent MSTS functional scores reflect that patients were satisfied and adjusted well to activities of daily living following surgery despite the complications.

    Matched MeSH terms: Tomography, X-Ray Computed
  15. Al-Adsani A, Dahniya MH, Al-Adsani N
    Postgrad Med J, 2001 Feb;77(904):127, 137-8.
    PMID: 11161092
    Matched MeSH terms: Tomography, X-Ray Computed/methods
  16. Al-Ameen Z, Sulong G
    Interdiscip Sci, 2015 Sep;7(3):319-25.
    PMID: 26199211 DOI: 10.1007/s12539-015-0022-1
    In computed tomography (CT), blurring occurs due to different hardware or software errors and hides certain medical details that are present in an image. Image blur is difficult to avoid in many circumstances and can frequently ruin an image. For this, many methods have been developed to reduce the blurring artifact from CT images. The problems with these methods are the high implementation time, noise amplification and boundary artifacts. Hence, this article presents an amended version of the iterative Landweber algorithm to attain artifact-free boundaries and less noise amplification in a faster application time. In this study, both synthetic and real blurred CT images are used to validate the proposed method properly. Similarly, the quality of the processed synthetic images is measured using the feature similarity index, structural similarity and visual information fidelity in pixel domain metrics. Finally, the results obtained from intensive experiments and performance evaluations show the efficiency of the proposed algorithm, which has potential as a new approach in medical image processing.
    Matched MeSH terms: Tomography, X-Ray Computed/methods*
  17. Al-Ameen Z, Sulong G
    Scanning, 2015 Mar-Apr;37(2):116-25.
    PMID: 25663630 DOI: 10.1002/sca.21187
    Contrast is a distinctive visual attribute that indicates the quality of an image. Computed Tomography (CT) images are often characterized as poor quality due to their low-contrast nature. Although many innovative ideas have been proposed to overcome this problem, the outcomes, especially in terms of accuracy, visual quality and speed, are falling short and there remains considerable room for improvement. Therefore, an improved version of the single-scale Retinex algorithm is proposed to enhance the contrast while preserving the standard brightness and natural appearance, with low implementation time and without accentuating the noise for CT images. The novelties of the proposed algorithm consist of tuning the standard single-scale Retinex, adding a normalized-ameliorated Sigmoid function and adapting some parameters to improve its enhancement ability. The proposed algorithm is tested with synthetically and naturally degraded low-contrast CT images, and its performance is also verified with contemporary enhancement techniques using two prevalent quality evaluation metrics-SSIM and UIQI. The results obtained from intensive experiments exhibited significant improvement not only in enhancing the contrast but also in increasing the visual quality of the processed images. Finally, the proposed low-complexity algorithm provided satisfactory results with no apparent errors and outperformed all the comparative methods.
    Matched MeSH terms: Tomography, X-Ray Computed
  18. Al-Shabi M, Lan BL, Chan WY, Ng KH, Tan M
    Int J Comput Assist Radiol Surg, 2019 Oct;14(10):1815-1819.
    PMID: 31020576 DOI: 10.1007/s11548-019-01981-7
    PURPOSE: Lung nodules have very diverse shapes and sizes, which makes classifying them as benign/malignant a challenging problem. In this paper, we propose a novel method to predict the malignancy of nodules that have the capability to analyze the shape and size of a nodule using a global feature extractor, as well as the density and structure of the nodule using a local feature extractor.

    METHODS: We propose to use Residual Blocks with a 3 × 3 kernel size for local feature extraction and Non-Local Blocks to extract the global features. The Non-Local Block has the ability to extract global features without using a huge number of parameters. The key idea behind the Non-Local Block is to apply matrix multiplications between features on the same feature maps.

    RESULTS: We trained and validated the proposed method on the LIDC-IDRI dataset which contains 1018 computed tomography scans. We followed a rigorous procedure for experimental setup, namely tenfold cross-validation, and ignored the nodules that had been annotated by

    Matched MeSH terms: Tomography, X-Ray Computed/methods*
  19. Al-Shaham AA, Samher AA
    J Plast Surg Hand Surg, 2010 Dec;44(6):318-21.
    PMID: 21446812 DOI: 10.3109/02844311003683713
    Despite the fact that cemento-ossifying fibromas of the maxilla may be quite large and locally aggressive, en-bloc excision is achieved by gentle blunt dissection, with the whole tumour mass peeled out from the adjacent structures. Until recently different fibro-osseous tumours that contained cementum were classified together as "cementomas". In 1992 The World Health Organization adopted a new classification that included these fibromas as benign osseous tumours. While such tumours of the mandible are common, those of the maxilla are rare. They are growth products of periodontal membrane remnant. The triggering mechanism in the formation of cementum outside the periodontal membrane remains unclear. We present a 35-year-old woman who had a giant expanding lobular mass in the right maxilla of 5 years duration. She had visual disturbances and nasal obstruction, and was treated successfully by surgical en-bloc resection of the tumour through an infraorbital transverse incision. The differential diagnosis included fibrous dysplasia, osteoid osteoma, osteoblastoma, chronic sclerosing osteomyelitis, ameloblastoma, squamous cell carcinoma of the maxillary sinus, calcifying epithelial odontogenic tumour (Pindborg tumour) and calcifying odontogenic cyst (Gorlin cyst). Histopathological examination confirmed a cemento-ossifying fibroma.
    Matched MeSH terms: Tomography, X-Ray Computed/methods
  20. Alaga A, Yew YX, Razul MK
    J R Coll Physicians Edinb, 2017 Dec;47(4):353-355.
    PMID: 29537407 DOI: 10.4997/JRCPE.2017.410
    A 47-year-old female, with multiple comorbidities, presented with a cough of two months, loss of weight and appetite. She was treated for pneumonia. A chest X-ray showed bilateral reticulonodular opacities. She was noted to have a vague central abdominal mass and a systolic murmur over the mitral region. Ultrasonography and computed tomography of the abdomen showed an omental mass and loculated ascites. Oesophagoduedenoscopy showed antral gastritis and during colonoscopy the surgical team was unable to advance the scope beyond 40 cm due to external compression. An echocardiogram showed a right atrial mass and a pericardial effusion over the posterior wall. A possible diagnosis of atrial myxoma was made. Sputum acid-fast bacillus was negative. The patient was treated empirically for disseminated tuberculosis and scheduled for bronchoscopy by the pulmonology team. The patient showed remarkable improvement after day 7 of anti-tuberculosis medication. GeneXpert study came back as positive. CT abdomen and echocardiogram repeated after 2 weeks of treatment showed reduction in the mass.
    Matched MeSH terms: Tomography, X-Ray Computed
Filters
Contact Us

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

External Links