EVALUATION OF IRRADIATION DOSES DELIVERED TO PATIENTS IN COMPUTED TOMOGRAPHY EXAMINATIONS IN 10 RADIOLOGY DEPARTMENTS IN DOUALA-CAMEROON

2020 ◽  
Vol 191 (3) ◽  
pp. 288-295
Author(s):  
Celestin Mpeke Mokubangele ◽  
Alexandre Ngwa Ebongue ◽  
Francisse Ouogue ◽  
Daniel Bongue ◽  
Boniface Moifo
Keyword(s):  
Computed Tomography ◽  
Ct Scan ◽  
Pediatric Population ◽  
Adult Population ◽  
Daily Practice ◽  
Ct Scans ◽  
Radiological Protection ◽  
Dose Length Product ◽  
Need To Evaluate ◽  
Adults And Children

Abstract Computed tomography (CT) scan is currently the most irradiating radio diagnostic procedure for the patients. The effective dose delivered by a CT-scan exploration corresponds to 1–20 years of natural irradiation of an individual. Hence, there is need to evaluate this medical exposure, in order to provide indicators and propose guidelines for its daily practice. The purpose of this work was to assess patient exposure levels due to CT-scan exams and propose a local diagnostic reference levels for the most common CT examinations performed in the radiology units of Douala/Cameroon. Data from 1775 CT scans, amongst which 10 different types of common CT examinations on adults and children, were collected, of which 1378 were adult CT scans and 397 were pediatric CT scans. The dose-length product (DLP) values in the adult population for head, abdomen–pelvic and lumber spine CT scans were high as compared to the Institute for Radiological Protection and Nuclear Safety recommendations and previous local DRL with an increase of 36, 15 and 23%, respectively. A general decrease of the DLP for CT-scans examinations in the pediatric population was observed.

Requesting physicians’ knowledge of X-radiation exposure from computed tomography scan examinations: A case study of two Nigerian tertiary hospitals

2020 ◽  
Vol 3 ◽  
pp. 36-39
Author(s):  
Samson O. Paulinus ◽  
Benjamin E. Udoh ◽  
Bassey E. Archibong ◽  
Akpama E. Egong ◽  
Akwa E. Erim ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Ionizing Radiation ◽  
Ct Scan ◽  
Radiation Exposure ◽  
Work Experience ◽  
Radiation Risk ◽  
Radiological Protection ◽  
X Ray ◽  
Tertiary Hospitals ◽  
Medical Exposure

Objective: Physicians who often request for computed tomography (CT) scan examinations are expected to have sound knowledge of radiation exposure (risks) to patients in line with the basic radiation protection principles according to the International Commission on Radiological Protection (ICRP), the Protection of Persons Undergoing Medical Exposure or Treatment (POPUMET), and the Ionizing Radiation (Medical Exposure) Regulations (IR(ME)R). The aim is to assess the level of requesting physicians’ knowledge of ionizing radiation from CT scan examinations in two Nigerian tertiary hospitals. Materials and Methods: An 18-item-based questionnaire was distributed to 141 practicing medical doctors, excluding radiologists with work experience from 0 to >16 years in two major teaching hospitals in Nigeria with a return rate of 69%, using a voluntary sampling technique. Results: The results showed that 25% of the respondents identified CT thorax, abdomen, and pelvis examination as having the highest radiation risk, while 22% said that it was a conventional chest X-ray. Furthermore, 14% concluded that CT head had the highest risk while 9% gave their answer to be conventional abdominal X-ray. In addition, 17% inferred that magnetic resonance imaging had the highest radiation risk while 11% had no idea. Furthermore, 25.5% of the respondents have had training on ionizing radiation from CT scan examinations while 74.5% had no training. Majority (90%) of the respondents were not aware of the ICRP guidelines for requesting investigations with very little (<3%) or no knowledge (0%) on the POPUMET and the IR(ME)R respectively. Conclusion: There is low level of knowledge of ionizing radiation from CT scan examinations among requesting physicians in the study locations.

Diagnostic Accuracy of Magnetic Resonance Imaging and Computed Tomography Scan in Young Athletes With Spondylolysis

2019 ◽  
Vol 58 (6) ◽  
pp. 671-676
Author(s):  
Amy M. West ◽  
Pierre A. d’Hemecourt ◽  
Olivia J. Bono ◽  
Lyle J. Micheli ◽  
Dai Sugimoto
Keyword(s):  
Magnetic Resonance Imaging ◽  
Computed Tomography ◽  
Magnetic Resonance ◽  
Ct Scan ◽  
False Negative ◽  
False Negative Rate ◽  
Ct Scans ◽  
Resonance Imaging ◽  
Young Athletes ◽  
Negative Rate

The objective of this study was to determine diagnostic accuracy of magnetic resonance imaging (MRI) and computed tomography (CT) scans in young athletes diagnosed with spondylolysis. A cross-sectional study was used. Twenty-two young athletes (14.7 ± 1.5 years) were diagnosed as spondylolysis based on a single-photon emission CT. Following the diagnosis, participants underwent MRI and CT scan imaging tests on the same day. The sensitivity and false-negative rate of the MRI and CT scans were analyzed. MRI test confirmed 13 (+) and 9 (−) results while CT test showed 17 (+) and 5 (−) results. The sensitivity and false-negative rate of MRI were, respectively, 59.1% (95% confidence interval [CI] = 36.7% to 78.5%) and 40.9% (95% CI = 21.5% to 63.3%). Furthermore, the sensitivity and false-negative rate of CT scan were 77.3% (95% CI = 54.2% to 91.3%) and 22.7% (95% CI = 0.09% to 45.8%). Our results indicated that CT scan is a more accurate imaging modality to diagnose spondylolysis compared with MRI in young athletes.

scholarly journals The Effect of Contrast-enhanced Computed Tomography (CT) Scans on the Calculated Dose of Radiotherapy in a Thorax Phantom

2021 ◽  
Vol In Press (In Press) ◽  
Author(s):  
Athar Ehtiati ◽  
Payman Hejazi ◽  
Mohsen Bakhshandeh ◽  
Ali Jabbary Arfaee ◽  
Eftekhar Rajab Bolookat ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Contrast Media ◽  
Ct Scan ◽  
Treatment Planning ◽  
Tumor Volume ◽  
Ct Scans ◽  
Contrast Enhanced ◽  
Enhanced Ct ◽  
Enhanced Computed Tomography ◽  
Contrast Enhanced Computed Tomography

Background: Despite the benefits of contrast-enhanced computed tomography (CT) scans in better tumor volume delineation, it can affect the accuracy of dose calculation in radiation therapy. This study examined this effect on a thorax phantom. Objectives: The influence of different variables including the concentrations of the Visipaque contrast media, tumor sizes, and CT scan energies on the dose measurement was examined. Methods: Transparent cylinders containing the contrast media were inserted in the lung area of the phantom and the CT scans were made. Non-enhanced CT scans were also acquired. Treatment planning using 2 opposite fields was performed on the CT scans and the doses were calculated in the treatment planning system. The results of the 2 sets of enhanced and non-enhanced CT scans were compared. Results: The correlation between concentration and the percentage of mean dose of the tumor volume was significant in 2 of the tumor sizes. The differences in the mean doses of the 2 plans were examined and more than 3% increase was observed in higher concentrations of the contrast media. Conclusions: According to this study, the suitable concentration of the contrast media administered and the CT scan energy should be considered. This would help to decrease the discrepancies between the calculated and delivered dose in radiotherapy treatments to a clinically acceptable level. The importance of time delays for CT scans after administration of the contrast media is emphasized.

scholarly journals Enlargement of Post-Traumatic Intracerebral Haematoma: Incidence and Time Course

2005 ◽  
Vol 33 (1) ◽  
pp. 119-122 ◽  
Author(s):  
WG Liu ◽  
Y Yao ◽  
JY Zhou ◽  
XF Yang
Keyword(s):  
Computed Tomography ◽  
Ct Scan ◽  
Time Course ◽  
Ct Scans ◽  
Intracerebral Haematoma ◽  
Automated Method ◽  
Haematoma Volume ◽  
Traumatic Intracerebral Haematoma ◽  
Radiographic Criterion ◽  
Post Traumatic

We retrospectively assessed the incidence and time course of enlargement in posttraumatic intracerebral haematoma (PTICH). Computed tomography (CT) scans from 165 patients who underwent a scan within 72 h and a repeat scan within 120 h of the onset of trauma were examined. A semi-automated method using region deformation-based segmentation was used to calculate the haematoma volume. The presence of haematoma enlargement was also determined based on a consensus by five observers. Seventy cases (42%) showed enlargement of the haematoma. The frequency of haematoma enlargement decreased as the interval between the onset of trauma and the initial scan increased. The discriminant value of the ratio of the haematoma volume in the second scan to that in the initial scan was ascertained, and the cut-off value for haematoma enlargement was determined to be 1.45. The radiographic criterion for enlargement in PTICH on CT scan was, therefore, defined as a ≥ 1.45 times increase in haematoma volume.

Prospective Study of the Correlation Between Postoperative Computed Tomography Scan and Primary Surgeon Assessment in Patients With Advanced Ovarian, Tubal, and Peritoneal Carcinoma Reported to Have Undergone Primary Surgical Cytoreduction to Residual Disease 1 cm or Less

2007 ◽  
Vol 25 (31) ◽  
pp. 4946-4951 ◽  
Author(s):  
Dennis S. Chi ◽  
Pedro T. Ramirez ◽  
Jerrold B. Teitcher ◽  
Svetlana Mironov ◽  
Debra M. Sarasohn ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Ct Scan ◽  
Residual Disease ◽  
Advanced Ovarian Cancer ◽  
Ct Scans ◽  
Eligibility Criteria ◽  
Primary Surgery ◽  
The Right ◽  
Analysis Scale ◽  
Tomography Scan

Purpose To compare surgeons' operative assessments of residual disease (RD) to those identified on postoperative computed tomography (CT) scans in patients with advanced ovarian carcinoma reported to have undergone optimal primary cytoreduction. Patients and Methods All patients at one of two institutions, who were scheduled to have primary surgery for presumed advanced ovarian cancer, were asked to consent to a postoperative CT scan if cytoreduction to ≤ 1 cm RD was reported. CT scan findings were graded using a qualitative analysis scale from 1 (normal) to 5 (definitely malignant). Results From January 2001 to September 2006, 285 patients were enrolled. A total of 78 patients met eligibility criteria and had postoperative CT scans. In 41 cases (52%), postoperative scan findings correlated with the surgical report of no RD more than 1 cm, and in seven cases (9%), the CT findings were indeterminate. In 10 cases (13%), more than 1 cm RD was noted by the radiologist as probably malignant, and in 20 cases (26%), definitely malignant. In these 30 cases, the radiologically reported median largest residual mass was 1.9 cm (range, 1.1 to 5.1), with RD more than 1 cm reported most commonly in the right upper quadrant (15 patients [50%]) and central abdomen (nine patients [30%]). Conclusion There was only a 52% correlation between surgeons' assessments and postoperative CT scan evaluations of RD in patients reported to have undergone optimal cytoreduction. Further study is required to determine whether this lack of correlation is due to rapid interval tumor regrowth, RD underestimated by the surgeons, and/or overestimated by the radiologists; and to determine the clinical implications of these discrepancies.

Imperial Needs, Imperial Methods: Chimú Ceramic Manufacturing Process Through CT Scan Analysis of Stirrup-Spout Bottles

2016 ◽  
Vol 27 (2) ◽  
pp. 238-256
Author(s):  
Valentine Wauters
Keyword(s):  
Computed Tomography ◽  
Ct Scan ◽  
Manufacturing Process ◽  
Ceramic Production ◽  
Ct Scans ◽  
Manufacturing Processes ◽  
Ceramic Assemblage ◽  
Ceramic Manufacturing ◽  
Industrial Level ◽  
Ct Scan Analysis

The stirrup-spout bottle is one of the most representative forms in the Chimú (A.D. 900-1470) ceramic repertoire. I discuss the ceramic assemblage of this coastal culture and describes more precisely the various manufacturing processes of the stirrup-spout bottle. Although molds used to produce these complex vessels are known today, only little information has been published on the various stages involved in their manufacture. My purpose is to contribute to this research using medical imaging computed tomography (CT) scans of intact stirrup-spout vessels. Based on my findings, I propose that changes in the construction of these vessels correlated with a transition in ceramic production to a semi-industrial level during the time of the Chimú Empire.

scholarly journals Prediction of Extrathyroidal Extension Using Ultrasonography and Computed Tomography

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Doh Young Lee ◽  
Tack-Kyun Kwon ◽  
Myung-Whun Sung ◽  
Kwang Hyun Kim ◽  
J. Hun Hah
Keyword(s):  
Computed Tomography ◽  
Ct Scan ◽  
Extrathyroidal Extension ◽  
Ct Scans ◽  
Imaging Features ◽  
Predictive Values ◽  
Preoperative Prediction ◽  
Ct Findings ◽  
Sensitivity Specificity ◽  
Thyroid Capsule

Objectives. The aim of the present study was to evaluate the value of high-resolution ultrasound (US) and computed tomography (CT) scan for preoperative prediction of the extrathyroidal extension (ETE).Methods. We analyzed the medical records of 377 patients with papillary thyroid carcinoma (PTC) with preoperative US and CT scan to calculate the sensitivity, specificity, and positive and negative predictive values of characteristics imaging features (such as contact and disruption of thyroid capsule) for the presence of ETE in postoperative pathologic examination. We also evaluated the diagnostic power for several combinations of US and CT findings.Results. ETE was present in 174 (46.2%) based on pathologic reports. The frequency of ETE was greater in the patients with greater degrees of tumor contact and disruption of capsule, as revealed by both US and CT scans (positive predictive value of 72.2% and 81.8%, resp.). Considering positive predictive values and AUC of US and CT categories, separately or combined, a combination of US and CT findings was most accurate for predicting ETE (83.0%, 0.744).Conclusions. This study suggests that ETE can be predicted most accurately by a combination of categories based on the findings of US and CT scans.

Radiation Dose from Diagnostic Computed Tomography in Saskatchewan

2009 ◽  
Vol 60 (2) ◽  
pp. 71-78 ◽  
Author(s):  
David A. Leswick ◽  
Nida S. Syed ◽  
Chance S. Dumaine ◽  
Hyun J. Lim ◽  
Derek A. Fladeland
Keyword(s):  
Computed Tomography ◽  
Significant Variation ◽  
Ct Scans ◽  
Dose Length Product ◽  
Volume Computed Tomography ◽  
The United Kingdom ◽  
Canadian Data ◽  
Effective Doses ◽  
Computed Tomography Dose Index ◽  
Dose Levels

Objective To calculate the effective dose from diagnostic computed tomography (CT) scans in Saskatchewan, Canada, and compare with other reported dose levels. Methods Data from CT scans were collected from 12 scanners in 7 cities across Saskatchewan. The patient age, scan type, and selected technique parameters including the dose length product and the volume computed tomography dose index were collected for a 2-week period. This information then was used to calculate effective doses patients are exposed to during CT examinations. Data from 2,061 clinically indicated CT examinations were collected, and of them 1,690 were eligible for analysis. Every examination during a 2-week period was recorded without selection. Results The average provincial estimated patient dose was as follows: head, 2.7 mSv (638 scans; standard deviation [SD], ±1.6); chest, 11.3 mSv (376 scans; SD, ±8.9); abdomen-pelvis, 15.5 mSv (578 scans; SD, ±10.0); abdomen, 11.7 mSv (80 scans; SD, ±11.48), and pelvis, 8.6 mSv (18 scans; SD, ±6.04). Significant variation in dose between the CT scanners was observed ( P = .049 for head, P = .001 for chest, and P = .034 for abdomen-pelvis). Conclusions Overall, the estimated dose from diagnostic CT examinations was similar to other previously published Canadian data from British Columbia. This dose varied slightly from some other published standards, including being higher than those found in a review conducted in the United Kingdom in 2003.

Can a CT be Omitted in Pediatric Minor Head Trauma?

2017 ◽  
Vol 16 (01) ◽  
pp. 001-007
Author(s):  
Maria Sinzig ◽  
Eveline Achatz ◽  
Günter Fasching ◽  
Christoph Arneitz
Keyword(s):  
Computed Tomography ◽  
Ct Scan ◽  
Radiation Exposure ◽  
Head Trauma ◽  
Neurological Status ◽  
Ct Scans ◽  
Minor Head Trauma ◽  
Pediatric Ct ◽  
Ct Protocol ◽  
In Infants And Children

AbstractThis study aimed to evaluate the need for radiation exposure in pediatric minor head trauma. Symptomatic patients after minor head trauma were observed for at least 24 hours in a 13-month period. A computed tomography (CT) scan was performed on children with a depressed neurological status. Two hundred fourteen patients with a mean age of 9.3 years were included. An intracranial hemorrhage (ICH) was diagnosed in three (1.4%) patients. The overall CT rate was 10.7%. The study concluded that neuro-observation without initial CT scans is safe in infants and children following minor head trauma. Special pediatric CT protocol can limit radiation exposure.

scholarly journals Assessment of Masseter Muscle Thickness in OSMF Patients - A Computed Tomography Study

2020 ◽  
Vol 7 (52) ◽  
pp. 3176-3179
Author(s):  
Choubarga Naik ◽  
Bimal Krishna Panda ◽  
Anisha Avijeeta ◽  
Barnanshu Pattnaik ◽  
Subha Soumya Dany ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Ct Scan ◽  
Masseter Muscle ◽  
Oral Submucous Fibrosis ◽  
Precancerous Lesion ◽  
Muscle Thickness ◽  
Ct Scans ◽  
P Value ◽  
Ct Scanner ◽  
Medical College

BACKGROUND Oral submucous fibrosis (OSMF) is the most common precancerous lesion, prevalent mostly in South East Asia. The habit of betel nut or gutkha chewing is the main cause for this. There is a direct association between gutkha chewing habit and development of OSMF, the reason being exaggerated forces on the masseter muscle due to vigorous chewing for prolonged period of time. So, the present study was done to evaluate the thickness of masseter muscle in OSMF patients. METHODS A total of 25 subjects were included in the study from January 2015 to December 2017. 25 OSMF patients belonging to the age group of 25-50 years who attended the outpatient department of Veer Surendra Sai Medical College and Hospital, Burla, with masseteric hypertrophy and betelnut or gutkha chewing habit for more than 5 years, were included in the study. The computed tomography (CT) scans were obtained using Siemens Somatom Sensation 4-slice CT scanner. During the scanning period, the patients were asked to keep their mouth gently closed and relaxed. Axial sections of the CT scans were assessed for masseter muscles. The thickness of the muscle was calculated using image-analysing software and the measurements made were in millimeter (mm). Tabulation was done and statistical analysis was done using Mann-Whitney U test. RESULTS The thickness of masseter muscle of right side was found to be more than the left side in all patients except for one patient and the outcome was statistically significant with one tailed p value < 0.01. CONCLUSIONS The duration and frequency of the habit were found to be directly proportional to masseter muscle thickness and also with the clinical progression of the disease. Similarly, we also concluded from our study that there exists an association of masseter muscle hypertrophy with OSMF, and CT scan meas KEYWORDS OSMF, Masseter Muscle, CT Scan

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