Abstract P082: Estimating Equation for Computed Tomography Derived Visceral Fat: The Multi-Ethnic Study of Atherosclerosis

Background: The only way to determine visceral fat separately from subcutaneous fat is through magnetic resonance imaging (MRI) or computed tomography (CT) scans. The use of MRI or CT scans is unacceptable for screening in the general population. Given this, estimating equations for visceral fat that use commonly collected clinical variables have potential utility. Methods: Data are from 1842 participants, aged 45 to 84, from the Multi-Ethnic Study of Atherosclerosis with visceral fat assessed by CT scan at study visit 2 or 3, and anthropometry measured at matched visits. We excluded 19 participants with reported thiazolidinedione use, 11 with waist circumference greater than 140cm, and 5 with BMI greater than 45kg/m 2 . Visceral fat area, measured in cm 2 , was calculated as the average area from two CT scan slices at the L4/L5 vertebrae. Visceral fat was naturally log transformed to account for non-normality. Anthropometric indices included: height(cm), weight(kg), BMI(kg/m 2 ), waist circumference(cm), hip circumference(cm), waist to hip ratio, and waist to height ratio. Other variables included sex, Black, Asian, and Hispanic race/ethnicities, and age. Data were separated into training and testing datasets containing 2/3 and 1/3 of the data, respectively. Multivariable linear models were used to generate coefficients for the estimating equations and included non-linear and interaction terms. The PRESS statistic, R 2 , and RMSE were used to determine goodness of fit and likelihood ratio tests were used for variable and model selection. Results: Models including multiple measures of anthropometry performed better than models including only waist circumference or BMI. Models including non-linear terms for anthropometry and interaction by sex and race performed better than simple linear models. After analysis, the final estimating equation was: Ln Visceral Fat = -8.64 + 0.006*age - 8.42*sex - 8.53*black - 0.099*weight + 0.41*bmi + 0.022*waist + 0.029*hip + 8.58*waist/hip - 0.00396*bmi 2 +0.00015*waist 2 - 0.0003*hip 2 - 4.89*(waist/hip) 2 - 0.014*weight*sex - 0.066*waist*sex + 0.076*hip*sex + 8.57*(waist/hip)*sex - 0.097*waist*black + 0.088*hip*black + 10.31*(waist/hip)*black. The R 2 in the testing dataset for this model was 0.62. The estimates of visceral fat from the final equation provided estimates within 10% of measured values for nearly 90% of the observations. Conclusion: Our final model, that predicts visceral fat from CT scans, is highly parsimonious involving only seven variables that can be easily collected in the clinical setting. This practical equation might help improve the estimation of visceral fat in order to determine who is at greatest risk for CVD and who might benefit most from weight loss interventions.

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

Clinical Pediatrics ◽

10.1177/0009922819832643 ◽

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.

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

International Journal of Cancer Management ◽

10.5812/ijcm.84158 ◽

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.

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

Journal of International Medical Research ◽

10.1177/147323000503300113 ◽

2005 ◽

Vol 33 (1) ◽

pp. 119-122 ◽

Cited By ~ 1

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.

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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

Journal of Clinical Oncology ◽

10.1200/jco.2007.12.2317 ◽

2007 ◽

Vol 25 (31) ◽

pp. 4946-4951 ◽

Cited By ~ 44

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.

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

Latin American Antiquity ◽

10.7183/1045-6635.27.2.238 ◽

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.

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Prediction of Extrathyroidal Extension Using Ultrasonography and Computed Tomography

International Journal of Endocrinology ◽

10.1155/2014/351058 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 9

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.

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Can a CT be Omitted in Pediatric Minor Head Trauma?

Journal of Pediatric Neurology ◽

10.1055/s-0037-1604420 ◽

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.

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

Journal of Evidence Based Medicine and Healthcare ◽

10.18410/jebmh/2020/646 ◽

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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Diagnostic Accuracy of CT Scans in Blunt Abdomical Trauma

10.53350/pjmhs2115103503 ◽

2021 ◽

Vol 15 (10) ◽

pp. 3503-3505

Author(s):

Azmat Ali ◽

Nadia Khattak ◽

Adnan Ahmed ◽

Jawad Ali Memon ◽

Maimoona Afsar ◽

...

Keyword(s):

Computed Tomography ◽

Diagnostic Accuracy ◽

Ct Scan ◽

Abdominal Trauma ◽

Blunt Abdominal Trauma ◽

Clinical Manifestations ◽

Retroperitoneal Hematoma ◽

Ct Scans ◽

Internal Bleeding ◽

Wide Range

Background and Aim: Blunt abdominal trauma may lead to a serious situation that necessitates prompt diagnosis and treatment. The intra-abdominal injury effective diagnosis is difficult in patient’s management in such cases. The present study aims to evaluate the diagnostic accuracy of computed tomography scans in active internal bleeding following abdominal trauma. Materials and Methods: This cross-sectional study was carried out on 84 blunt abdominal trauma patients in the Department of Radiology Hayatabad Medical Complex, Peshawar for duration of six months from January 2021 to June 2021. All the patients with no clinical manifestations underwent diagnostic CT scans. Those who had a positive CT scan underwent laparotomy. The remaining patients were monitored for 24 hours and were discharged in case of no serious issues. Demographic details, patient information, trauma mechanism, CT scan indications, and findings, and laparotomy results were recorded. Regarding injured organs, specificity, sensitivity, and diagnostic accuracy of CT scans were determined. For individual cases, CT scans specificity, sensitivity, and accuracy were calculated. SPSS version 20 was used for data analysis. Results: This study included 84 patients, out of which 73 (86.9%) were male and 11(13.1%) were female. Patients aged 20-40 years were more prevalent 47 (56%), followed by those aged over 40 years were 20 (23.8%) and 10 to 19 years old were 17 (20.2%). Liver and spleen injuries had the highest CT scan sensitivity of 87.5% and 96.7% respectively. On the other hand, The CT scan's specificity was high in the injured kidneys (94%) and retroperitoneal hematoma 97.3% compared to other organ’s injuries. The diagnostic accuracy of CT scans in the identification of liver, kidney injuries, spleen, and retroperitoneal hematoma injuries was 93.7%, 92.3%, 96.2%, and 92.3% respectively. Conclusion: Our study found that CT scans are capable of detecting a wide range of injuries. CT scans are exceptionally valuable for assessing blunt abdominal injuries with active internal bleeding patients Furthermore, CT investigation is quick and extensively accessible. CT can produce high-resolution images with MPR and scanning protocol. Keywords: Diagnostic Accuracy; Abdominal Trauma Injuries, Computed Tomography (CT)

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Diagnostic Accuracy of Chest Computed Tomography Scans for Suspected Patients With COVID-19: Receiver Operating Characteristic Curve Analysis (Preprint)

10.2196/preprints.19424 ◽

2020 ◽

Author(s):

Lianpin Wu ◽

Qike Jin ◽

Jie Chen ◽

Jiawei He ◽

David M Brett-Major ◽

...

Keyword(s):

Computed Tomography ◽

Nucleic Acid ◽

Ct Scan ◽

Receiver Operating Characteristic Curve ◽

Operating Characteristic ◽

Characteristic Curve ◽

Curve Analysis ◽

Ct Scans ◽

Nucleic Acid Testing ◽

Operating Characteristic Curve

BACKGROUND Computed tomography (CT) scans are increasingly available in clinical care globally. They enable a rapid and detailed assessment of tissue and organ involvement in disease processes that are relevant to diagnosis and management, particularly in the context of the COVID-19 pandemic. OBJECTIVE The aim of this paper is to identify differences in the CT scan findings of patients who were COVID-19 positive (confirmed via nucleic acid testing) to patients who were confirmed COVID-19 negative. METHODS A retrospective cohort study was proposed to compare patient clinical characteristics and CT scan findings in suspected COVID-19 cases. A multivariable logistic model with LASSO (least absolute shrinkage and selection operator) selection for variables was used to identify the good predictors from all available predictors. The area under the curve (AUC) with 95% CI was calculated for each of the selected predictors and the combined selected key predictors based on receiver operating characteristic curve analysis. RESULTS A total of 94 (56%) patients were confirmed positive for COVID-19 from the suspected 167 patients. We found that elderly people were more likely to be infected with COVID-19. Among the 94 confirmed positive patients, 2 (2%) patients were admitted to an intensive care unit. No patients died during the study period. We found that the presence, distribution, and location of CT lesions were associated with the presence of COVID-19. White blood cell count, cough, and a travel history to Wuhan were also the top predictors for COVID-19. The overall AUC of these selected predictors is 0.97 (95% CI 0.93-1.00). CONCLUSIONS Taken together with nucleic acid testing, we found that CT scans can allow for the rapid diagnosis of COVID-19. This study suggests that chest CT scans should be more broadly adopted along with nucleic acid testing in the initial assessment of suspected COVID-19 cases, especially for patients with nonspecific symptoms.

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