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Displaying publications 161 - 169 of 169 in total

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Assessing changes in microstructural integrity of white matter tracts in children with leukaemia following exposure to chemotherapy

Ramli N, Lim CH, Rajagopal R, Tan LK, Seow P, Ariffin H

Pediatr Radiol, 2020 08;50(9):1277-1283.
PMID: 32591982 DOI: 10.1007/s00247-020-04717-x

BACKGROUND: Intrathecal and intravenous chemotherapy, specifically methotrexate, might contribute to neural microstructural damage.
OBJECTIVE: To assess, by diffusion tensor imaging, microstructural integrity of white matter in paediatric patients with acute lymphoblastic leukaemia (ALL) following intrathecal and intravenous chemotherapy.
MATERIALS AND METHODS: Eleven children diagnosed with de novo ALL underwent MRI scans of the brain with diffusion tensor imaging (DTI) prior to commencement of chemotherapy and at 12 months after diagnosis, using a 3-tesla (T) MRI scanner. We investigated the changes in DTI parameters in white matter tracts before and after chemotherapy using tract-based spatial statistics overlaid on the International Consortium of Brain Mapping DTI-81 atlas. All of the children underwent formal neurodevelopmental assessment at the two study time points.
RESULTS: Whole-brain DTI analysis showed significant changes between the two time points, affecting several white matter tracts. The tracts demonstrated longitudinal changes of decreasing mean and radial diffusivity. The neurodevelopment of the children was near compatible for age at the end of ALL treatment.
CONCLUSION: The quantification of white matter tracts changes in children undergoing chemotherapy showed improving longitudinal values in DTI metrics (stable fractional anisotropy, decreasing mean and radial diffusivity), which are incompatible with deterioration of microstructural integrity in these children.

Matched MeSH terms: Image Interpretation, Computer-Assisted
Fulltext Retinal vascular geometry in Asian persons with diabetes and retinopathy

Cheung CY, Lamoureux E, Ikram MK, Sasongko MB, Ding J, Zheng Y, et al.

J Diabetes Sci Technol, 2012 May 01;6(3):595-605.
PMID: 22768891 DOI: 10.1177/193229681200600315

Purpose: Our purpose was to examine the relationship of retinal vascular parameters with diabetes and retinopathy in an older Asian population.

Methods: Retinal photographs from participants of a population-based survey of Asian Malay persons aged 40-80 years were analyzed. Specific retinal vascular parameters (tortuosity, branching angle, fractal dimension, and caliber) were measured using a semiautomated computer-based program. Diabetes was defined as random plasma glucose ≥ 11.1 mmol/liter, the use of diabetes medication, or physician-diagnosed diabetes. Retinopathy signs were graded from photographs using the modified Airlie House classification system.

Results: A total of 2735 persons were included in the study. Persons with diabetes (n = 594) were more likely to have straighter (less tortuous) arterioles and wider arteriolar and venular caliber than those without diabetes (n = 2141). Among subjects with diabetes, those with retinopathy had wider venular caliber than those without retinopathy (211.3 versus 204.9 mm, p = .001). Among nondiabetic subjects, however, those with retinopathy had more tortuous venules than those without retinopathy [5.19(×10(4)) versus 4.27(×10(4)), p < .001].

Conclusions: Retinal vascular parameters varied by diabetes and retinopathy status in this older Asian cohort. Our findings suggest that subtle alterations in retinal vascular architecture are influenced by diabetes.

Matched MeSH terms: Image Interpretation, Computer-Assisted
Fulltext A multi-resolution textural approach to diagnostic neuropathology reporting

Fauzi MF, Gokozan HN, Elder B, Puduvalli VK, Pierson CR, Otero JJ, et al.

J Neurooncol, 2015 Sep;124(3):393-402.
PMID: 26255070 DOI: 10.1007/s11060-015-1872-4

We present a computer aided diagnostic workflow focusing on two diagnostic branch points in neuropathology (intraoperative consultation and p53 status in tumor biopsy specimens) by means of texture analysis via discrete wavelet frames decomposition. For intraoperative consultation, our methodology is capable of classifying glioblastoma versus metastatic cancer by extracting textural features from the non-nuclei region of cytologic preparations based on the imaging characteristics of glial processes, which appear as anisotropic thin linear structures. For metastasis, these are homogeneous in appearance, thus suitable and extractable texture features distinguish the two tissue types. Experiments on 53 images (29 glioblastomas and 24 metastases) resulted in average accuracy as high as 89.7 % for glioblastoma, 87.5 % for metastasis and 88.7 % overall. For p53 interpretation, we detect and classify p53 status by classifying staining intensity into strong, moderate, weak and negative sub-classes. We achieved this by developing a novel adaptive thresholding for detection, a two-step rule based on weighted color and intensity for the classification of positively and negatively stained nuclei, followed by texture classification to classify the positively stained nuclei into the strong, moderate and weak intensity sub-classes. Our detection method is able to correctly locate and distinguish the four types of cells, at 85 % average precision and 88 % average sensitivity rate. These classification methods on the other hand recorded 81 % accuracy in classifying the positive and negative cells, and 60 % accuracy in further classifying the positive cells into the three intensity groups, which is comparable with neuropathologists' markings.

Matched MeSH terms: Image Interpretation, Computer-Assisted
Fulltext Design process of cementless femoral stem using a nonlinear three dimensional finite element analysis

Baharuddin MY, Salleh ShH, Zulkifly AH, Lee MH, Noor AM, A Harris AR, et al.

BMC Musculoskelet Disord, 2014;15:30.
PMID: 24484753 DOI: 10.1186/1471-2474-15-30

Minimal available information concerning hip morphology is the motivation for several researchers to study the difference between Asian and Western populations. Current use of a universal hip stem of variable size is not the best option for all femur types. This present study proposed a new design process of the cementless femoral stem using a three dimensional model which provided more information and accurate analysis compared to conventional methods.

Matched MeSH terms: Radiographic Image Interpretation, Computer-Assisted
Fulltext Standardization of Malaysian adult female nasal cavity

Lee CF, Abdullah MZ, Ahmad KA, Lutfi Shuaib I

Comput Math Methods Med, 2013;2013:519071.
PMID: 23840279 DOI: 10.1155/2013/519071

This research focuses on creating a standardized nasal cavity model of adult Malaysian females. The methodology implemented in this research is a new approach compared to other methods used by previous researchers. This study involves 26 females who represent the test subjects for this preliminary study. Computational fluid dynamic (CFD) analysis was carried out to better understand the characteristics of the standardized model and to compare it to the available standardized Caucasian model. This comparison includes cross-sectional areas for both half-models as well as velocity contours along the nasal cavities. The Malaysian female standardized model is larger in cross-sectional area compared to the standardized Caucasian model thus leading to lower average velocity magnitudes. The standardized model was further evaluated with four more Malaysian female test subjects based on its cross-sectional areas and average velocity magnitudes along the nasal cavities. This evaluation shows that the generated model represents an averaged and standardized model of adult Malaysian females.

Matched MeSH terms: Radiographic Image Interpretation, Computer-Assisted
Linked color imaging improves the visibility of various featured colorectal polyps in an endoscopist's visibility and color difference value

Yoshida N, Naito Y, Yasuda R, Murakami T, Hirose R, Ogiso K, et al.

Int J Colorectal Dis, 2017 Sep;32(9):1253-1260.
PMID: 28725959 DOI: 10.1007/s00384-017-2855-z

PURPOSE: Linked color imaging (LCI) by laser endoscopy is a novel narrow band light observation. In this study, we analyzed the efficacy of LCI for improving the various featured colorectal polyp's visibility utilizing a subjective endoscopist's visibility scoring and objective color difference (CD) value.
METHODS: We retrospectively reviewed two pictures both with white light (WL) and LCI for 54 consecutive neoplastic polyps 2-20 mm in size. All pictures were evaluated by four endoscopists according to a published polyp visibility score from four (excellent visibility) to one (poor visibility). Additionally, we calculated CD value between each polyp and surrounding mucosa in LCI and WL using an original software.
RESULTS: The mean polyp visibility scores of LCI (3.11 ± 1.05) were significantly higher than those of WL (2.50 ± 1.09, P

Matched MeSH terms: Image Interpretation, Computer-Assisted
Fulltext Negative correlation of cortical thickness with the severity and duration of abdominal pain in Asian women with irritable bowel syndrome

Chua CS, Bai CH, Shiao CY, Hsu CY, Cheng CW, Yang KC, et al.

PLoS One, 2017;12(8):e0183960.
PMID: 28859146 DOI: 10.1371/journal.pone.0183960

BACKGROUND & AIMS: Irritable bowel syndrome (IBS) manifests as chronic abdominal pain. One pathophysiological theory states that the brain-gut axis is responsible for pain control in the intestine. Although several studies have discussed the structural changes in the brain of IBS patients, most of these studies have been conducted in Western populations. Different cultures and sexes experience different pain sensations and have different pain responses. Accordingly, we aimed to identify the specific changes in the cortical thickness of Asian women with IBS and to compare these data to those of non-Asian women with IBS.
METHODS: Thirty Asian female IBS patients (IBS group) and 39 healthy individuals (control group) were included in this study. Brain structural magnetic resonance imaging was performed. We used FreeSurfer to analyze the differences in the cortical thickness and their correlations with patient characteristics.
RESULTS: The left cuneus, left rostral middle frontal cortex, left supramarginal cortex, right caudal anterior cingulate cortex, and bilateral insula exhibited cortical thinning in the IBS group compared with those in the controls. Furthermore, the brain cortical thickness correlated negatively the severity as well as duration of abdominal pain.
CONCLUSIONS: Some of our findings differ from those of Western studies. In our study, all of the significant brain regions in the IBS group exhibited cortical thinning compared with those in the controls. The differences in cortical thickness between the IBS patients and controls may provide useful information to facilitate regulating abdominal pain in IBS patients. These findings offer insights into the association of different cultures and sexes with differences in cortical thinning in patients with IBS.

Matched MeSH terms: Image Interpretation, Computer-Assisted
Localization and prediction of malignant potential in recurrent pheochromocytoma/paraganglioma (PCC/PGL) using 18F-FDG PET/CT

Fikri AS, Kroiss A, Ahmad AZ, Zanariah H, Lau WF, Uprimny C, et al.

Acta Radiol, 2014 Jun;55(5):631-40.
PMID: 24037430 DOI: 10.1177/0284185113504330

To our knowledge, data are lacking on the role of 18F-FDG PET/CT in the localization and prediction of neuroendocrine tumors, in particular the pheochromocytoma/paraganglioma (PCC/PGL) group.

Matched MeSH terms: Radiographic Image Interpretation, Computer-Assisted
Patterns of intracranial hemorrhage in petrous temporal bone fracture

Asha'ari ZA, Ahmad R, Rahman J, Yusof RA, Kamarudin N

Auris Nasus Larynx, 2012 Apr;39(2):151-5.
PMID: 21592698 DOI: 10.1016/j.anl.2011.02.010

To study the relationship pattern of intracranial hemorrhage in cases of traumatic petrous temporal bone fracture.

Matched MeSH terms: Image Interpretation, Computer-Assisted