Displaying publications 61 - 80 of 1490 in total

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  1. Majid AA, Rathakrishnan V, Alhady SF
    J R Soc Med, 1991 Nov;84(11):686-7.
    PMID: 1744882
    Matched MeSH terms: Tomography, X-Ray Computed*
  2. Harun HH, Abdul Karim MK, Abbas Z, Abdul Rahman MA, Sabarudin A, Ng KH
    Diagnostics (Basel), 2020 Sep 09;10(9).
    PMID: 32917029 DOI: 10.3390/diagnostics10090681
    In this study, we aimed to estimate the probability of cancer risk induced by CT pulmonary angiography (CTPA) examinations concerning effective body diameter. One hundred patients who underwent CTPA examinations were recruited as subjects from a single institution in Kuala Lumpur. Subjects were categorized based on their effective diameter size, where 19-25, 25-28, and >28 cm categorized as Groups 1, 2, and 3, respectively. The mean value of the body diameter of the subjects was 26.82 ± 3.12 cm, with no significant differences found between male and female subjects. The risk of cancer in breast, lung, and liver organs was 0.009%, 0.007%, and 0.005% respectively. The volume-weighted CT dose index (CTDIvol) was underestimated, whereas the size-specific dose estimates (SSDEs) provided a more accurate description of the radiation dose and the risk of cancer. CTPA examinations are considered safe but it is essential to implement a protocol optimized following the As Low as Reasonably Achievable (ALARA) principle.
    Matched MeSH terms: Cone-Beam Computed Tomography; Computed Tomography Angiography
  3. Rais NNM, Bradley DA, Hashim A, Osman ND, Noor NM
    Appl Radiat Isot, 2019 Nov;153:108810.
    PMID: 31351374 DOI: 10.1016/j.apradiso.2019.108810
    For a range of doses familiarly incurred in computed tomography (CT), study is made of the performance of Germanium (Ge)-doped fibre dosimeters formed into cylindrical and flat shapes. Indigenously fabricated 2.3 mol% and 6 mol% Ge-dopant concentration preforms have been used to produce flat- and cylindrical-fibres (FF and CF) of various size and diameters; an additional 4 mol% Ge-doped commercial fibre with a core diameter of 50 μm has also been used. The key characteristics examined include the linearity index f(d), dose sensitivity and minimum detectable dose (MDD), the performance of the fibres being compared against that of lithium-fluoride based TLD-100 thermoluminescence (TL) dosimeters. For doses in the range 2-40 milligray (mGy), delivered at constant potential of 120 kilovoltage (kV), both the fabricated and commercial fibres demonstrate supralinear behaviours at doses  4 mGy. In terms of dose sensitivity, all of the fibres show superior TL sensitivity when compared against TLD-100, the 2.3 mol% and 6 mol% Ge-doped FF demonstrating the greatest TL sensitivity at 84 and 87 times that of TLD-100. The TL yields for the novel Ge-doped silica glass render them appealing for use within the present medical imaging dose range, offering linearity at high sensitivity down to less than 2 mGy.
    Matched MeSH terms: Tomography, X-Ray Computed/methods*
  4. Ooi EH, Lee KW, Yap S, Khattab MA, Liao IY, Ooi ET, et al.
    Comput Biol Med, 2019 03;106:12-23.
    PMID: 30665137 DOI: 10.1016/j.compbiomed.2019.01.003
    Effects of different boundary conditions prescribed across the boundaries of radiofrequency ablation (RFA) models of liver cancer are investigated for the case where the tumour is at the liver boundary. Ground and Robin-type conditions (electrical field) and body temperature and thermal insulation (thermal field) conditions are examined. 3D models of the human liver based on publicly-available CT images of the liver are developed. An artificial tumour is placed inside the liver at the boundary. Simulations are carried out using the finite element method. The numerical results indicated that different electrical and thermal boundary conditions led to different predictions of the electrical potential, temperature and thermal coagulation distributions. Ground and body temperature conditions presented an unnatural physical conditions around the ablation site, which results in more intense Joule heating and excessive heat loss from the tissue. This led to thermal damage volumes that are smaller than the cases when the Robin type or the thermal insulation conditions are prescribed. The present study suggests that RFA simulations in the future must take into consideration the choice of the type of electrical and thermal boundary conditions to be prescribed in the case where the tumour is located near to the liver boundary.
    Matched MeSH terms: Tomography, X-Ray Computed*
  5. Hoe Khoo AC, Ang SF
    Indian J Nucl Med, 2020 10 21;35(4):364-366.
    PMID: 33642772 DOI: 10.4103/ijnm.IJNM_123_20
    Thymic carcinoma is a rare thymic epithelial cancer which is not only locally invasive but also highly aggressive disease. The prognosis for this cancer is poor and the surgery remains the mainstay of treatment. Thymic carcinomas have been shown to metastasize to the lymph nodes, lung, and liver. A 63-year old male who was successfully treated for thymic cancer in 2015, presented with metastatic disease recurrence to the spinal cord. We share interesting images of the spinal cord lesions as well as pituitary metastases that were incidentally detected on restaging 18F-fluorodeoxyglucose positron emission tomography-computed tomography.
    Matched MeSH terms: Positron Emission Tomography Computed Tomography
  6. Kaewput C, Suppiah S, Vinjamuri S
    World J Nucl Med, 2018 Jan-Mar;17(1):34-40.
    PMID: 29398963 DOI: 10.4103/wjnm.WJNM_16_17
    The aim of our study was to correlate tumor uptake of 68Ga-DOTA-NOC positron emission tomography/computed tomography (PET/CT) with the pathological grade of neuroendocrine tumors (NETs). 68Ga-DOTA-NOC PET/CT examinations in 41 patients with histopathologically proven NETs were included in the study. Maximum standardized uptake value (SUVmax) and averaged SUV SUVmean of "main tumor lesions" were calculated for quantitative analyses after background subtraction. Uptake on main tumor lesions was compared and correlated with the tumor histological grade based on Ki-67 index and pathological differentiation. Classification was performed into three grades according to Ki-67 levels; low grade: Ki-67 <2, intermediate grade: Ki-67 3-20, and high grade: Ki-67 >20. Pathological differentiation was graded into well- and poorly differentiated groups. The values were compared and evaluated for correlation and agreement between the two parameters was performed. Our study revealed negatively fair agreement between SUVmax of tumor and Ki-67 index (r = -0.241) and negatively poor agreement between SUVmean of tumor and Ki-67 index (r = -0.094). SUVmax of low-grade, intermediate-grade, and high-grade Ki-67 index is 26.18 ± 14.56, 30.71 ± 24.44, and 6.60 ± 4.59, respectively. Meanwhile, SUVmean of low-grade, intermediate-grade, and high-grade Ki-67 is 8.92 ± 7.15, 9.09 ± 5.18, and 3.00 ± 1.38, respectively. As expected, there was statistically significant decreased SUVmax and SUVmean in high-grade tumors (poorly differentiated NETs) as compared with low- and intermediate-grade tumors (well-differentiated NETs). SUV of 68Ga-DOTA-NOC PET/CT is not correlated with histological grade of NETs. However, there was statistically significant decreased tumor uptake of 68Ga-DOTA-NOC in poorly differentiated NETs as compared with the well-differentiated group. As a result of this pilot study, we confirm that the lower tumor uptake of 68Ga-DOTA-NOC may be associated with aggressive behavior and may, therefore, result in poor prognosis.
    Matched MeSH terms: Positron Emission Tomography Computed Tomography
  7. Lau I, Wong YH, Yeong CH, Abdul Aziz YF, Md Sari NA, Hashim SA, et al.
    Quant Imaging Med Surg, 2019 Jan;9(1):107-114.
    PMID: 30788252 DOI: 10.21037/qims.2019.01.02
    Current visualization techniques of complex congenital heart disease (CHD) are unable to provide comprehensive visualization of the anomalous cardiac anatomy as the medical datasets can essentially only be viewed from a flat, two-dimensional (2D) screen. Three-dimensional (3D) printing has therefore been used to replicate patient-specific hearts in 3D views based on medical imaging datasets. This technique has been shown to have a positive impact on the preoperative planning of corrective surgery, patient-doctor communication, and the learning experience of medical students. However, 3D printing is often costly, and this impedes the routine application of this technology in clinical practice. This technical note aims to investigate whether reducing 3D printing costs can have any impact on the clinical value of the 3D-printed heart models. Low-cost and a high-cost 3D-printed models based on a selected case of CHD were generated with materials of differing cost. Quantitative assessment of dimensional accuracy of the cardiac anatomy and pathology was compared between the 3D-printed models and the original cardiac computed tomography (CT) images with excellent correlation (r=0.99). Qualitative evaluation of model usefulness showed no difference between the two models in medical applications.
    Matched MeSH terms: Tomography; Tomography, X-Ray Computed
  8. Wan Ab Naim WN, Sun Z, Liew YM, Chan BT, Jansen S, Lei J, et al.
    Quant Imaging Med Surg, 2021 May;11(5):1723-1736.
    PMID: 33936960 DOI: 10.21037/qims-20-814
    Background: The study aims to analyze the correlation between the maximal diameter (both axial and orthogonal) and volume changes in the true (TL) and false lumens (FL) after stent-grafting for Stanford type B aortic dissection.

    Method: Computed tomography angiography was performed on 13 type B aortic dissection patients before and after procedure, and at 6 and 12 months follow-up. The lumens were divided into three regions: the stented area (Region 1), distal to the stent graft to the celiac artery (Region 2), and between the celiac artery and the iliac bifurcation (Region 3). Changes in aortic morphology were quantified by the increase or decrease of diametric and volumetric percentages from baseline measurements.

    Results: At Region 1, the TL diameter and volume increased (pre-treatment: volume =51.4±41.9 mL, maximal axial diameter =22.4±6.8 mm, maximal orthogonal diameter =21.6±7.2 mm; follow-up: volume =130.7±69.2 mL, maximal axial diameter =40.1±8.1 mm, maximal orthogonal diameter =31.9+2.6 mm, P<0.05 for all comparisons), while FL decreased (pre-treatment: volume =129.6±150.5 mL; maximal axial diameter =43.0±15.8 mm; maximal orthogonal diameter =28.3±12.6 mm; follow-up: volume =66.6±95.0 mL, maximal axial diameter =24.5±19.9 mm, maximal orthogonal diameter =16.9±13.7, P<0.05 for all comparisons). Due to the uniformity in size throughout the vessel, high concordance was observed between diametric and volumetric measurements in the stented region with 93% and 92% between maximal axial diameter and volume for the true/false lumens, and 90% and 92% between maximal orthogonal diameter and volume for the true/false lumens. Large discrepancies were observed between the different measurement methods at regions distal to the stent graft, with up to 46% differences between maximal orthogonal diameter and volume.

    Conclusions: Volume measurement was shown to be a much more sensitive indicator in identifying lumen expansion/shrinkage at the distal stented region.

    Matched MeSH terms: Tomography, X-Ray Computed; Computed Tomography Angiography
  9. Tan WY, Ng JZL, Ajit Bapat R, Vijaykumar Chaubal T, Kishor Kanneppedy S
    J Prosthet Dent, 2021 May;125(5):766.e1-766.e8.
    PMID: 33752904 DOI: 10.1016/j.prosdent.2021.02.018
    STATEMENT OF PROBLEM: Lingual plate perforation can be life-threatening when vital structures are damaged during implant placement. Knowledge of the anatomy of lingual concavities is imperative for safe implant surgery.

    PURPOSE: The purpose of this clinical study was to determine the prevalence of type of posterior mandibular ridge morphology in a Malaysian population and to evaluate the buccolingual width of the alveolar ridge (Wb and Wc); alveolar ridge height (Vcb); and concavity angle, length, and depth for both left and right first and second molars in different age groups and sexes by using cone beam computed tomography (CBCT).

    MATERIAL AND METHODS: Bilateral posterior mandibular lingual concavities at the first and second molars were retrospectively studied in cross-sectional views of 150 CBCT scans (n=600 sites evaluated). The sample size was calculated at a power of 80%, confidence interval of 95%, and margin of error of .05. The buccolingual width from the base and crest of the ridge and the ridge height were measured to determine the type of ridge. For the U-shaped ridge, the concavity angle, length, and depth were assessed. The independent t test was used to compare mean values of CBCT measurements between sexes and tooth type, while the ANOVA and Pearson chi-squared test were used to determine the correlations with age groups and types of ridge morphology, respectively. To compare the left and right readings for first and second molars in the same patient, the paired t test was performed (α=.05 for all tests).

    RESULTS: The Pearson correlation showed a strong agreement between the 2 examiners with an interobserver reliability of 87.3%. Significant difference was noted in all dimensional measurements when comparing right and left first and second molars (P

    Matched MeSH terms: Cone-Beam Computed Tomography*
  10. 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; Tomography, X-Ray Computed
  11. Yusof NAM, Noor E, Reduwan NH, Yusof MYPM
    Clin Oral Investig, 2021 Mar;25(3):923-932.
    PMID: 32535703 DOI: 10.1007/s00784-020-03380-8
    OBJECTIVES: The aim of this study was to evaluate the accuracy of cone beam computed tomography (CBCT), periapical radiograph, and intrasurgical linear measurements in the assessment of molars with furcation defects.

    MATERIALS AND METHODS: This parallel, single-blinded, randomised controlled trial (RCT) consisted of 22 periodontitis patients who had molar with advanced furcation involvement (FI). All patients followed the same inclusion criteria and were treated following the same protocol, except for radiographic evaluation (CBCT vs. periapical). This study proposed and evaluated five parameters that represent the extent and severity of furcation defects in molars teeth, including CEJ-BD (clinical attachment loss), BL-H (depth), BL-V (height), RT (root trunk), and FW (width).

    RESULTS: There were no statistically significant differences between CBCT and intrasurgical linear measurements for any clinical parameter (p > 0.05). However, there were statistically significant differences in BL-V measurements (p 

    Matched MeSH terms: Cone-Beam Computed Tomography; Spiral Cone-Beam Computed Tomography
  12. Aws Hashim Ali Al-Kadhim, Azlan Jaafar, Mohd Nazrin Isa
    MyJurnal
    Nonsurgical retreatment involves removing mechanical barriers such as gutta-percha to achieve proper cleaning and disinfection. The complexity of the anatomy of molar tooth gives challenge in retreatment procedure. Thus, this study evaluates the amount of residual gutta-percha after retreatment with rotary files (Reciproc Blue®) from each maxillary first molar canal using cone-beam computed tomography (CBCT) and the time required to accomplish it. Nine freshly extracted maxillary molars were instrumented and obturated. Preoperative CBCT was taken, and retreatment was done using Reciproc Blue®. CBCT was taken post retreatment, and the residual volume percentage of gutta-percha from each canal was calculated. The total retreatment time was recorded, and the data were statistically analyzed. The result shows no statistically significant difference in the amount of residual filling material in mesiobuccal, distobuccal, and palatal canal for maxillary first molar and total time used for retreatment with Reciproc Blue® system.

    Matched MeSH terms: Cone-Beam Computed Tomography; Spiral Cone-Beam Computed Tomography
  13. Ahmed HMA, Ibrahim N, Mohamad NS, Nambiar P, Muhammad RF, Yusoff M, et al.
    Int Endod J, 2021 Jul;54(7):1056-1082.
    PMID: 33527452 DOI: 10.1111/iej.13486
    Adequate knowledge and accurate characterization of root and canal anatomy is an essential prerequisite for successful root canal treatment and endodontic surgery. Over the years, an ever-increasing body of knowledge related to root and canal anatomy of the human dentition has accumulated. To correct deficiencies in existing systems, a new coding system for classifying root and canal morphology, accessory canals and anomalies has been introduced. In recent years, micro-computed tomography (micro-CT) and cone beam computed tomography (CBCT) have been used extensively to study the details of root and canal anatomy in extracted teeth and within clinical settings. This review aims to discuss the application of the new coding system in studies using micro-CT and CBCT, provide a detailed guide for appropriate characterization of root and canal anatomy and to discuss several controversial issues that may appear as potential limitations for proper characterization of roots and canals.
    Matched MeSH terms: Cone-Beam Computed Tomography; Spiral Cone-Beam Computed Tomography
  14. Kee AR, Yip VCH, Tay ELT, Lim CW, Cheng J, Teo HY, et al.
    BMC Ophthalmol, 2020 Nov 10;20(1):440.
    PMID: 33167902 DOI: 10.1186/s12886-020-01701-9
    BACKGROUND: To understand the differences between two different optical coherence tomography angiography (OCTA) devices in detecting glaucomatous from healthy eyes by comparing their vascular parameters, diagnostic accuracy and test-retest reliability.

    METHODS: A cross-sectional observational study was performed on healthy and glaucoma subjects, on whom two sets of OCTA images of optic disc and macula were acquired using both AngioVue (Optovue, USA) and Swept Source (Topcon, Japan) OCTA devices during one visit. A novel in-house software was used to calculate the vessel densities. Diagnostic accuracy of the machines in differentiating healthy versus glaucomatous eyes was determined using area under the receiver operating characteristic curve (AUROC) and test-retest repeatability of the machines was also evaluated.

    RESULTS: A total of 80 healthy and 38 glaucomatous eyes were evaluated. Glaucomatous eyes had reduced mean vessel density compared to healthy controls in all segmented layers of the optic disc and macula using AngioVue (p ≤ 0.001). However, glaucomatous eyes had higher mean vessel density on optic disc scans using Swept Source, with lack of statistically significant difference between healthy and glaucomatous eyes. The AUROC showed better diagnostic accuracy of AngioVue (0.761-1.000) compared to Swept Source (0.113-0.644). The test-retest reliability indices were generally better using AngioVue than Swept Source.

    CONCLUSIONS: AngioVue showed better diagnostic capability and test-retest reliability compared to Swept Source. Further studies need to be undertaken to evaluate if there is any significant difference between the various machines in diagnosing and monitoring glaucoma.

    Matched MeSH terms: Tomography, Optical Coherence*
  15. Razali MASM, Ahmad MZ, Shuaib IL, Osman ND
    Radiat Prot Dosimetry, 2020 Jun 13;188(2):213-221.
    PMID: 31885043 DOI: 10.1093/rpd/ncz278
    The aim of this study was to propose local diagnostic reference levels (LDRLs) for the most common computed tomography (CT) examinations (including contrast and non-contrast scan phase) performed at Advanced Medical and Dental Institute (AMDI), Universiti Sains Malaysia (USM), Malaysia. A retrospective CT dose survey of 1488 subjects from January 2015 until December 2018 was performed at AMDI USM, Malaysia. The proposed DRLs were established at 50th and 75th percentile of dose distribution for all dose metrics (CT dose index [CTDI]; CTDIvol, CTDIw and dose-length product). The proposed LDRLs were compared with national DRLs and other established DRLs. The 10 most common CT examinations at AMDI were thorax-abdomen-pelvis (TAP) CT (46%), followed by pelvis CT (17%), abdomen-pelvis CT (10%), brain/head CT (9%) and other CT protocols. The local DRLs were established using the third quartile values of dose distribution and were categorized based on CT region protocols. Most of the proposed DRLs were exceeded the national DRLs (63%) and other international DRLs (67%). From the dose auditing, almost half of the recent dose data (for year 2018) exceeded the proposed local DRLs and the unusual dose were observed in TAP, brain/head and pelvis CT examinations. The unusual higher dose could be due to higher mAs settings, higher number of scan phase for contrast study and higher pitch factor. The local DRLs should be established for dose optimization and reduction of the occurrence of excessive radiation exposure to the patients. The establishment of the Ads and LDRLs should also consider all the factors that affect the variation in DRLs such as CT technology, scanning protocols and population characteristics. The local dose distribution should always be revised for improvement of the current local practice.
    Matched MeSH terms: Tomography, X-Ray Computed*
  16. Lee SA, Chiu CK, Chan CYW, Yaakup NA, Wong JHD, Kadir KAA, et al.
    Spine J, 2020 07;20(7):1114-1124.
    PMID: 32272253 DOI: 10.1016/j.spinee.2020.03.015
    BACKGROUND CONTEXT: Biopsy is important to obtain microbiological and histopathological diagnosis in spine infections and tumors. To date, there have been no prospective randomized trials comparing fluoroscopic guided and computed tomography (CT) transpedicular biopsy techniques. The goal of this study was to evaluate the accuracy, safety, and diagnostic outcome of these two diagnostic techniques.

    PURPOSE: To evaluate the accuracy, safety, and diagnostic outcome of fluoroscopic guided and CT transpedicular biopsy techniques.

    STUDY DESIGN: Prospective randomized trial.

    PATIENT SAMPLE: Sixty consecutive patients with clinical symptoms and radiological features suggestive of spinal infection or malignancy were recruited and randomized into fluoroscopic or CT guided spinal biopsy groups. Both groups were similar in terms of patient demographics, distribution of spinal infections and malignancy cases, and the level of biopsies.

    OUTCOME MEASURES: The primary outcome measure was diagnostic accuracy of both methods, determined based on true positive, true negative, false positive, and false negative biopsy findings. Secondary outcome measures included radiation exposure to patients and doctors, complications, and postbiopsy pain score.

    METHODS: A transpedicular approach was performed with an 8G core biopsy needle. Specimens were sent for histopathological and microbiological examinations. Diagnosis was made based on biopsy results, clinical criteria and monitoring of disease progression during a 6-month follow up duration. Clinical criteria included presence of risk factors, level of inflammatory markers and magnetic resonance imaging findings. Radiation exposure to patients and doctors was measured with dosimeters.

    RESULTS: There was no significant difference between the diagnostic accuracy of fluoroscopic and CT guided spinal biopsy (p=0.67) or between the diagnostic accuracy of spinal infection and spinal tumor in both groups (p=0.402 for fluoroscopy group and p=0.223 for CT group). Radiation exposure to patients was approximately 26 times higher in the CT group. Radiation exposure to doctors in the CT group was approximately 2 times higher compared to the fluoroscopic group if a lead shield was not used. Lead shields significantly reduced radiation exposure to doctors anywhere from 2 to 8 times. No complications were observed for either group and the differences in postbiopsy pain scores were not significant.

    CONCLUSIONS: The accuracy, procedure time, complication rate and pain score for both groups were similar. However, radiation exposure to patients and doctors were significantly higher in the CT group without lead protection. With lead protection, radiation to doctors reduced significantly.

    Matched MeSH terms: Tomography, X-Ray Computed*
  17. Salama A, Malekmohammadi A, Mohanna S, Rajkumar R
    Int J Biomed Imaging, 2017;2017:3589324.
    PMID: 29225613 DOI: 10.1155/2017/3589324
    This paper presents a multitasking electrical impedance tomography (EIT) system designed to improve the flexibility and durability of an existing EIT system. The ability of the present EIT system to detect, locate, and reshape objects was evaluated by four different experiments. The results of the study show that the system can detect and locate an object with a diameter as small as 1.5 mm in a testing tank with a diameter of 134 mm. Moreover, the results demonstrate the ability of the current system to reconstruct an image of several dielectric object shapes. Based on the results of the experiments, the programmable EIT system can adapt the EIT system for different applications without the need to implement a new EIT system, which may help to save time and cost. The setup for all the experiments consisted of a testing tank with an attached 16-electrode array made of titanium alloy grade 2. The titanium alloy electrode was used to enhance EIT system's durability and lifespan.
    Matched MeSH terms: Tomography; Tomography, X-Ray Computed
  18. Hishar, H., Salasiah, M., Fathinul Fikri, A. S., Nordin, A. J.
    MyJurnal
    A shift to administration of optimal dose of 18F-FDG between 4 and 5 MBq/kg from the current practice of higher doses potentially yields a reasonable-to-excellent PET image. For this purpose, whole-body MIP images of 32 patients (23 men, 9 women, age 51.9 ± 13.7 years), administered with 18F-FDG (activity 5.3 ± 0.5 MBq/kg, 45 minutes uptake time) for whole-body PET/CT examinations, were evaluated. Image quality was assessed visually by two radiologists using a three-point scoring scale: poor, reasonable and excellent. The interobserver agreement revealed a kappa value higher than 0.7. Therefore, the utilisation of 18F-FDG dose between 4 and 5MBq/kg is considered an optimum dose for whole-body PET/CT examination.
    Matched MeSH terms: Tomography, X-Ray Computed; Positron-Emission Tomography
  19. Fathinul Fikri,A.S, Nordin, A.J, Cheah, Y.K., Ahmad Saad, F.N.
    MyJurnal
    The escalating costs of conventional diagnostic technology in oncology have yet to obviate futile surgery intervention and the spiralling treatment cost. The evolution in engineering technology which looks at the correlation of the anatomy and the function of tumours i.e. Positron Emission Tomography-Computed Tomography (PET-CT) have impacted on the improved diagnostic accuracy and treatment in oncology. Clinical data have demonstrated that the information provided by PET/CT often changes patient management. This review addresses the value of PET-CT as a surrogate molecular marker in tumours and to discuss some issues in adopting PET/CT in routine daily practice as supported by the numbers of literature reviews of its application in oncology since it was first commercialised in 2001. The description of the technology used in multimodality imaging has gained encouraging interest among physicians, policy makers and insurance companies on the importance of the PET-CT, for which roles are not limited to the staging, disease prognostication and treatment monitoring with potential impact on treatment cost and justification of radiation safety for the patient. PET/CT is a useful tool in cancer investigation as evidenced by its role as a surrogate marker in underpinning the cellular reprogramming of different pathological entities.
    Matched MeSH terms: Tomography, X-Ray Computed; Positron-Emission Tomography
  20. Rafidah, Z., Jaafar, M.S., Shukri, A., Khader, M.A.A., Abdel Munem, E.
    MyJurnal
    The objective of this study was to compare the acquired image of teflon, human bone equivalent material on a Positron Emission Tomography/Computed Tomography (PET/CT) scanner with Monte Carlo simulation (MCNP). The cylindrical shape teflon phantom with dimensions of 19.5 cm length and 5.0 cm diameter was used for imaging with different settings of kilovolts (kV) and milliamperes (mA) of PET/CT. In this simulation, the photon flux in each pixel was accumulated by the Flux Image Radiograph (FIR) tally as flux image detectors and the image was plotted using Microsoft Office Excel. Results show that MCNP image was comparable with that of CT image and the obtained MCNP image depends on pixels size of the FIR tally.
    Matched MeSH terms: Tomography, X-Ray Computed; Positron-Emission Tomography
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