Displaying all 3 publications

Abstract:
Sort:
  1. 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.
  2. Hasan MI, Noordin SS, Hami R, Ishak N, Achuthan A
    Blood Transfus, 2022 Nov;20(6):446-453.
    PMID: 35848625 DOI: 10.2450/2022.0018-22
    BACKGROUND: Low hemoglobin level is a common cause of donor deferral and results in a huge loss of the donor pool. This study aimed to evaluate the effectiveness of a mobile application as an educational tool to enhance donor return and improve hemoglobin levels after deferral.

    MATERIALS AND METHODS: This was an interventional study involving 382 blood donors who were deferred for low hemoglobin. The donors were divided equally into two groups: a control group and the intervention group. The control group received standard management for low hemoglobin deferral, which includes a short counseling session and a 1-month course of oral iron therapy. The intervention group used a mobile application in addition to standard management. The primary endpoint was the number of blood donors who returned during the 7 months of follow-up. The secondary endpoints were the hemoglobin increment at the first visit after the donors' deferral.

    RESULTS: The return rate was higher in the intervention group, with 81.2% of the donors returning in the 7 months of follow-up compared to 66% of the control group (p<0.001). Male and female donors had mean hemoglobin increments of 1.0 g/dL and 0.7 g/dL, respectively, in the intervention group, compared to decrements of 0.2 g/dL and 0.4 g/dL, respectively, in the control group (p<0.001). Multivariable analysis showed a significant association between intervention method, education level and donation status on donor return (p=0.015, p<0.001, and p<0.001, respectively).

    DISCUSSION: Higher return rate and greater hemoglobin increase in the interventional group could be attributed to features in the mobile application. Repeat donors had the highest odds of returning to donate, followed by those with a tertiary level of education, and those given the mobile application. This study showed that a mobile application was effective in enhancing donor return and increasing hemoglobin level among deferred blood donors on their first return.

  3. Abdulkadir MK, Osman ND, Achuthan A, Nasirudin RA, Ahmad MZ, Zain NHM, et al.
    J Med Phys, 2024;49(3):456-463.
    PMID: 39526162 DOI: 10.4103/jmp.jmp_26_24
    BACKGROUND AND PURPOSE: Size-specific dose estimates (SSDE) have been introduced into computed tomography (CT) dosimetry to tailor patients' unique sizes to facilitate accurate CT radiation dose quantification and optimization. The purpose of this study was to develop and validate an automated algorithm for the determination of patient size (effective diameter) and SSDE.

    MATERIALS AND METHODS: A MATLAB platform was used to develop software of algorithms based on image segmentation techniques to automate the calculation of patient size and SSDE. The algorithm was used to automatically estimate the individual size and SSDE of four CT dose index phantoms and 80 CT images of pediatric patients comprising head, thorax, and abdomen scans. For validation, the American Association of Physicists in Medicine (AAPM) manual methods were used to determine the patient's size and SSDE for the same subjects. The accuracy of the proposed algorithm in size and SSDE calculation was evaluated for agreement with the AAPM's estimations (manual) using Bland-Altman's agreement and Pearson's correlation coefficient. The normalized error, system bias, and limits of agreement (LOA) between methods were derived.

    RESULTS: The results demonstrated good agreement and accuracy between the automated and AAPM's patient size estimations with an error rate of 1.9% and 0.27% on the patient and phantoms study, respectively. A 1% percentage difference was found between the automated and manual (AAPM) SSDE estimates. A strong degree of correlation was seen with a narrow LOA between methods for clinical study (r > 0.9771) and phantom study (r > 0.9999).

    CONCLUSION: The proposed automated algorithm provides an accurate estimation of patient size and SSDE with negligible error after validation.

Related Terms
Filters
Contact Us

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

External Links