scholarly journals Preferred characterization of orbital infection (cellulitis) with exposure dose and relative medication

2019 ◽  
Vol 7 (2) ◽  
pp. 605
Author(s):  
Mohammed Ahmed Ali Omer
Keyword(s):  
Optic Nerve ◽  
Image Interpretation ◽  
Exposure Dose ◽  
Dose Length Product ◽  
Cross Sectional ◽  
Ct Dose ◽  
Cross Section Spectrum ◽  
Ct Dose Index ◽  
Patient Radiation Exposure

Background: A retrospective study presenting the endemic orbital infection (cellulitis) that breakout during dusty storm season; aiming to ascertain and showing the precedence of MRI for diagnosis of orbital infection rather than CT and revealing the diagnostic abilities of cross-sectional matrices spectrum.Methods: Based on retrospective collection of diagnostics (CT and MRI) information for randomly selected patients with cellulitis and the targeting the relevant data (image interpretation, exposure dose (DLP and CTDIvol), age, BMI and matrix cross-section spectrum findings).Results: The exposure dose of orbital CT exam was 59.4 (mGy) as CT dose index (CTDIvol) and 917.3 (mGy/cm) as dose length product (DLP) that increase by increment of age and BMI. The obese patients only exposed to dose exceeding the National Diagnostic Reference by 2.8%. MRI confirmed the inflammation around the optic nerve and extension to posterio-inferior portion of the globe and affecting the optic nerve with left sided proptosis (0.5cm) better than CT. The cross-sectional matrix successfully revealed that: the Lt optic nerve’s gray value (density) increases by a factor of 17.7 (a u) and enlarged by 5 pixels greater than the Rt optic nerve. Thickening, rough surface increased gray value by 30.5 (a u), muco-thickening and choncheal enlargement at the medial boarder of Lt orbit as 10.0 pixel and Lt eye ball enlarged by a factor of 10.9 pixels.Conclusions: MRI wisely diagnose orbital infection with more details and overcoming patient radiation exposure and usage of image spectrum gives detailed characterization of lesion morphology.

scholarly journals Whole Body Low Dose Computed Tomography Using Third-Generation Dual-Source Multidetector With Spectral Shaping: Protocol Optimization and Literature Review

Dose-Response ◽  
2020 ◽  
Vol 18 (4) ◽  
pp. 155932582097313
Author(s):  
Dario Baldi ◽  
Liberatore Tramontano ◽  
Vincenzo Alfano ◽  
Bruna Punzo ◽  
Carlo Cavaliere ◽  
...  
Keyword(s):  
Effective Dose ◽  
Low Dose ◽  
Whole Body ◽  
Dose Length Product ◽  
Osteolytic Lesions ◽  
Subjective Image Quality ◽  
Ct Dose ◽  
Dual Source ◽  
Ct Dose Index ◽  
Low Dose Computed Tomography

For decades, the main imaging tool for multiple myeloma (MM) patient’s management has been the conventional skeleton survey. In 2014 international myeloma working group defined the advantages of the whole-body low dose computed tomography (WBLDCT) as a gold standard, among imaging modalities, for bone disease assessment and subsequently implemented this technique in the MM diagnostic workflow. The aim of this study is to investigate, in a group of 30 patients with a new diagnosis of MM, the radiation dose (CT dose index, dose-length product, effective dose), the subjective image quality score and osseous/extra-osseous findings rate with a modified WBLDCT protocol. Spectral shaping and third-generation dual-source multidetector CT scanner was used for the assessment of osteolytic lesions due to MM, and the dose exposure was compared with the literature findings reported until 2020. Mean radiation dose parameters were reported as follows: CT dose index 0.3 ± 0.1 mGy, Dose-Length Product 52.0 ± 22.5 mGy*cm, effective dose 0.44 ± 0.19 mSv. Subjective image quality was good/excellent in all subjects. 11/30 patients showed osteolytic lesions, with a percentage of extra-osseous findings detected in 9/30 patients. Our data confirmed the advantages of WBLDCT in the diagnosis of patients with MM, reporting an effective dose for our protocol as the lowest among previous literature findings.

scholarly journals Establishment of diagnostic reference levels arising from common CT examinations in Semnan County, Iran

2019 ◽  
Vol 25 (1) ◽  
pp. 51-55 ◽  
Author(s):  
Daryoush Khoramian ◽  
Soroush Sistani ◽  
Peyman Hejazi
Keyword(s):  
Cervical Spine ◽  
The Other ◽  
Reference Level ◽  
Ct Scanner ◽  
Dose Length Product ◽  
Ct Dose ◽  
Patient Doses ◽  
Ct Dose Index ◽  
Ct Scanners ◽  
Dose Levels

Abstract Objective: The literature has approved that the use of the concept of diagnostic reference level (DRL) as a part of an optimization process could help to reduce patient doses in diagnostic radiology comprising the Computed Tomography (CT) examinations. There are four public/governmental CT centers in the province (Semnan, Iran) and, to our knowledge, after about 12 years since the launch of the first CT scanner in the province there is no dosimetry information on those CT scanners. The aim of this study was to evaluate CT dose indices with the aim of the establishment of the DRL for head, chest, cervical spine, and abdomen-pelvis examinations. Methods: Scan parameters of 381 patients were collected during two months from 4 CT scanners. The CT dose index (CTDI) was measured using a calibrated ionization chamber on two cylindrical poly methyl methacrylate (PMMA) phantoms. For each sequences, weighted CTDI (CTDIw), volumetric CTDI (CTDIv) and dose length product (DLP) were calculated. The 75th percentile was proposed as the criterion for DRL values. Results: Proposed DRL (CTDIw, CTDIv, DLP) for the head, chest, cervical spine, and abdomen-pelvis were (46.1 mGy, 46.1 mGy, 723 mGy × cm), (13.8 mGy, 12.0 mGy, 377 mGy × cm), (40.0 mGy, 40.0 mGy, 572 mGy × cm) and (14.9 mGy, 12.1 mGy, 524 mGy × cm), respectively. Conclusion: Comparison with the others results from the other countries indicates that the head, chest and abdomen-pelvis scans in our region are lower or in the range of the other studies investigated in terms of dose. In the case of cervical spine scanning it’s necessary to review and regulate scan protocols to reach acceptable dose levels.

scholarly journals Chest CT Usage in Covid-19 Pneumonia: Multicenter Study on Radiation Doses and Diagnostic Quality in Brazil

2021 ◽  
Author(s):  
Monica Bernardo ◽  
Fatemeh Homayounieh ◽  
Maria Cristina Rodel Cuter ◽  
Luiz Mário Bellegard ◽  
Homero Medeiros Oliveira Junior ◽  
...  
Keyword(s):  
Respiratory Motion ◽  
Chest Ct ◽  
Radiation Doses ◽  
Dose Length Product ◽  
Diagnostic Quality ◽  
Ct Dose ◽  
Entire Lung ◽  
Information Number ◽  
Ct Dose Index ◽  
Volume Ct

Abstract We assessed variations in chest CT usage, radiation dose and image quality in COVID-19 pneumonia. Our study included all chest CT exams performed in 533 patients from 6 healthcare sites from Brazil. We recorded patients’ age, gender and body weight and the information number of CT exams per patient, scan parameters and radiation doses (volume CT dose index—CTDIvol and dose length product—DLP). Six radiologists assessed all chest CT exams for the type of pulmonary findings and classified CT appearance of COVID-19 pneumonia as typical, indeterminate, atypical or negative. In addition, each CT was assessed for diagnostic quality (optimal or suboptimal) and presence of artefacts. Artefacts were frequent (367/841), often related to respiratory motion (344/367 chest CT exams with artefacts) and resulted in suboptimal evaluation in mid-to-lower lungs (176/344) or the entire lung (31/344). There were substantial differences in CT usage, patient weight, CTDIvol and DLP across the participating sites.

Establishment of national diagnostic reference levels (NDRL) for computed tomographic (CT) procedures in Sri Lanka: first nation-wide dose survey

2021 ◽  
Author(s):  
T Amalaraj ◽  
Duminda Satharasinghe ◽  
Aruna Pallewatte ◽  
Jeyasingam Jeyasugiththan
Keyword(s):  
Sri Lanka ◽  
Diagnostic Reference Levels ◽  
Reference Levels ◽  
Standard Size ◽  
Dose Length Product ◽  
Computed Tomographic ◽  
Ct Dose ◽  
Contrast Enhanced ◽  
Ct Dose Index ◽  
First Time

Abstract The main purpose of this study was to establish the national diagnostic reference levels (NDRLs) for common CT procedures for the first time in Sri Lanka. Patient morphometric, exposure parameters, and dose data such as volume CT dose index (CTDIvol) and dose length product (DLP) were collected from 5666 patients who underwent 22 procedure types. The extreme dose values were filteblue before analysis to ensure that the data comes from standard size patients. The median of the dose distribution was calculated for each institution, and the third quartile value of the median distribution was consideblue as the NDRL. Based on the inclusion and exclusion criteria, 4592 patients data from 17 procedure types were consideblue for NDRL establishment covering 41\% of the country's total CT machines. The proposed NDRLs based on CTDIvol and DLP for non-contrast (NC) head:82.2 mGy/1556 mGy.cm, contrast-enhanced (CE) head: 82.2 mGy/1546 mGy.cm, chest-NC:7.4 mGy/350 mGy.cm, chest-CE:8.3 mGy/464 mGy.cm, abdomen NC:10.5 mGy/721 mGy.cm, abdomen arterial (A) phase:13.4 mGy/398 mGy.cm, abdomen venous (V) phase:10.8 mGy/460 mGy.cm, abdomen delay (D) phase:12.6 mGy/487 mGy.cm, sinus NC:30.2 mGy/452 mGy.cm, lumbar spine--NC:24.1 mGy/1123 mGy.cm, neck-NC:27.5 mGy/670 mGy.cm, high resolutions CT (HRCT) of chest:10.3 mGy/341 mGy.cm, kidney, ureter and bladder (KUB) NC:19.4 mGy/929 mGy.cm, chest to pelvis (CAP) NC:10.8 mGy/801 mGy.cm, CAP-A:10.4 mGy/384 mGy.cm, CAP-V:10.5 mGy/534 mGy.cm and CAP-D:16.8 mGy/652 mGy.cm. Although the proposed NDRLs are comparable with other countries, the observed broad dose distributions between the CT machines within the country indicate that dose optimisation strategies for Sri Lanka should be implemented for most of the CT facilities.

Use of Multiphase CT Protocols in 18 Countries: Appropriateness and Radiation Doses

2020 ◽  
pp. 084653711988839 ◽  
Author(s):  
Shivam Rastogi ◽  
Ramandeep Singh ◽  
Riddhi Borse ◽  
Petra Valkovic Zujic ◽  
Doris Segota ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Chest Ct ◽  
Radiation Doses ◽  
Energy Agency ◽  
Dose Length Product ◽  
Ct Dose ◽  
Clinical Indications ◽  
Ct Dose Index ◽  
Multiphase Ct ◽  
Routine Chest

Purpose: To assess the frequency, appropriateness, and radiation doses associated with multiphase computed tomography (CT) protocols for routine chest and abdomen–pelvis examinations in 18 countries. Materials and Methods: In collaboration with the International Atomic Energy Agency, multi-institutional data on clinical indications, number of scan phases, scan parameters, and radiation dose descriptors (CT dose–index volume; dose–length product [DLP]) were collected for routine chest (n = 1706 patients) and abdomen–pelvis (n = 426 patients) CT from 18 institutions in Asia, Africa, and Europe. Two radiologists scored the need for each phase based on clinical indications (1 = not indicated, 2 = probably indicated, 3 = indicated). We surveyed 11 institutions for their practice regarding single-phase and multiphase CT examinations. Data were analyzed with the Student t test. Results: Most institutions use multiphase protocols for routine chest (10/18 institutions) and routine abdomen–pelvis (10/11 institutions that supplied data for abdomen–pelvis) CT examinations. Most institutions (10/11) do not modify scan parameters between different scan phases. Respective total DLP for 1-, 2-, and 3-phase routine chest CT was 272, 518, and 820 mGy·cm, respectively. Corresponding values for 1- to 5-phase routine abdomen–pelvis CT were 400, 726, 1218, 1214, and 1458 mGy cm, respectively. For multiphase CT protocols, there were no differences in scan parameters and radiation doses between different phases for either chest or abdomen–pelvis CT ( P = 0.40-0.99). Multiphase CT examinations were unnecessary in 100% of routine chest CT and in 63% of routine abdomen–pelvis CT examinations. Conclusions: Multiphase scan protocols for the routine chest and abdomen–pelvis CT examinations are unnecessary, and their use increases radiation dose.

OPTIMIZATION OF RADIATION DOSE IN CT IMAGING: ESTABLISHING THE INSTITUTIONAL DIAGNOSTIC REFERENCE LEVELS AND PATIENT DOSE AUDITING

2019 ◽  
Vol 188 (2) ◽  
pp. 213-221 ◽  
Author(s):  
Mohd Amir Syahmi Mat Razali ◽  
Muhamad Zabidi Ahmad ◽  
Ibrahim Lutfi Shuaib ◽  
Noor Diyana Osman
Keyword(s):  
Dose Distribution ◽  
Population Characteristics ◽  
Contrast Study ◽  
Diagnostic Reference Levels ◽  
Reference Levels ◽  
Dose Length Product ◽  
Ct Dose ◽  
Dose Metrics ◽  
Ct Technology ◽  
Ct Dose Index

Abstract 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.

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