Trends of CT Use in the Adult Emergency Department in a Tertiary Academic Hospital of Korea during 2001-2010

Objective

We wanted to assess the trends of CT examinations that were conducted in an adult emergency department (ED).

Materials and Methods

We searched the medical database to identify adult patients (≥ 18 years) who had visited the ED and the number of CT examinations of the patients during the period from January 2001 to December 2010. We also analyzed the types of CT scans performed in terms of body parts, they were as follows; head CTs, facial bone CTs, neckl CTs, chest CTs, abdominal CTs, and miscellaneous CTs. Further, miscellaneous CTs were subdivided as CT angiography and others.

Results

A total of 113656 CT scans were examined for 409439 adult ED patients during a 10-year period, and the number of CT scans increased by 255% (from 4743 CTs in 2001 to 16856 CTs in 2010), while the adult ED patient volume increased by 34% during the same period. Although the head CTs proportionally occupied the most, the facial bone CTs had the largest rate of increase (3118%), followed by cervical CTs (1173%), chest CTs (455%), miscellaneous CTs (388%; 862% and 84% for CT angiography and others, respectively), abdominal CTs (315%) and head CTs (95%) per 1000 patients during the decade.

Conclusion

CT use in adult ED has increased at a rate that far exceeds the growth of ED patient volume, with facial bone CTs and cervical CTs having the largest increasing rate, followed by chest CTs, miscellaneous CTs, abdominal CTs and head CTs.     

Pediatric CT scan usage in Japan: results of a hospital survey

Purpose The aim of this study was to examine the usage parameters of diagnostic computed tomography (CT) in children because of concerns of possible overuse in Japanese hospitals, including the “technical” CT exposure settings and the “clinical” grounds for CT requests. Materials and methods We examined the methodology at the radiology department to reduce radiation exposure to children and performed a retrospective study on pediatric CT requests during a 1-year period at Nagasaki University Hospital. The parameters of diagnostic CT usage for minor head trauma and acute appendicitis were studied in detail. Results CT radiation dose settings are adjusted for children based on guidelines issued by the Japan Radiological Society, with few limitations. CT requests were made for 62% of minor head trauma cases and 76% of cases clinically suspected to be acute appendicitis. These figures are considerably higher than those reported by studies in the United Kingdom, Canada, or the United States. No specific guidelines are advocated regarding CT usage for minor head trauma. The diagnosis of acute appendicitis in children is almost routinely referred for “confirmation” by CT. Conclusion CT radiation risks to children at Japanese hospitals need to be considered more seriously. Physicians should be encouraged to follow diagnostic algorithms that help avoid unnecessary CT usage in children.     

Temporal Trends in Imaging Utilization for Suspected Substance Use Disorder in an Academic Emergency Radiology Department

PurposeTo assess temporal trends and utilization patterns of diagnostic imaging performed for substance use disorder (SUD)-related indications in an academic radiology emergency department (ED).MethodsRetrospective analyses of ED imaging examinations acquired from 2005 to 2015 were performed. Imaging examinations performed for suspected SUD-related indications, based on the order history, were compared with those without a SUD-related indication. Unadjusted analyses comparing demographic and imaging characteristics between SUD-related versus non-SUD-related indications used Wilcoxon and Pearson’s χ² tests. Multivariable logistic regression models, within each imaging modality subgroup and combined, were employed to examine the odds of imaging examinations having an SUD-related indication as a function of demographic and imaging characteristics.ResultsAmong 938,245 examinations, 0.17% had an SUD-related indication. Patients with SUD-related indications were younger (mean 37.2 ± 11.1 versus 53.5 ± 22.4, P < .001) and more commonly male (65% versus 52%, P < .001). The proportions of MR (17%), spine (17%), and extremities (33%) studies performed for SUD-related indications were larger among SUD than non-SUD indications (6%, 8%, 26%, respectively, all P < .001). Regression analysis demonstrated the odds of acquiring an ED imaging examination with an SUD-related indication significantly increased over time (P < .001, adjusted odds ratio [aOR] = 1.06), which was most pronounced among MR (P < .001, aOR = 1.23). For all regression models, younger age, male gender, and body part being imaged were identified as independent predictors of an SUD-related indication for ED imaging.ConclusionImaging performed for an SUD-related indication represented a small but increasing subset of overall ED imaging. Utilization of MR for SUD-related indications significantly outpaced growth of MR without SUD-related indications.     

Diagnostic Performance of CT Angiography in Patients Visiting Emergency Department with Overt Gastrointestinal Bleeding

Objective

To investigate the diagnostic performance of computed tomography angiography (CTA) in identifying the cause of bleeding and to determine the clinical features associated with a positive test result of CTA in patients visiting emergency department with overt gastrointestinal (GI) bleeding.

Materials and Methods

We included 111 consecutive patients (61 men and 50 women; mean age: 63.4 years; range: 28-89 years) who visited emergency department with overt GI bleeding. They underwent CTA as a first-line diagnostic modality from July through December 2010. Two radiologists retrospectively reviewed the CTA images and determined the presence of any definite or potential bleeding focus by consensus. An independent assessor determined the cause of bleeding based on other diagnostic studies and/or clinical follow-up. The diagnostic performance of CTA and clinical characteristics associated with positive CTA results were analyzed.

Results

To identify a definite or potential bleeding focus, the diagnostic yield of CTA was 61.3% (68 of 111). The overall sensitivity, specificity, positive predictive value (PPV), and negative predictive value were 84.8% (67 of 79), 96.9% (31 of 32), 98.5% (67 of 68), and 72.1% (31 of 43), respectively. Positive CTA results were associated with the presence of massive bleeding (p = 0.001, odds ratio: 11.506).

Conclusion

Computed tomography angiography as a first-line diagnostic modality in patients presenting with overt GI bleeding showed a fairly high accuracy. It could identify definite or potential bleeding focus with a moderate diagnostic yield and a high PPV. CTA is particularly useful in patients with massive bleeding.     

Retrospective Analysis of Emergency Computed Tomography Imaging Utilization at an Academic Centre: An Analysis of Clinical Indications and Outcomes

PurposeTo explore resource utilization through evaluation of computed tomography (CT) imaging trends in the emergency department by examining common indications/outcomes for imaging in this setting.MethodsA retrospective analysis of clinical indications/outcomes for all CT imaging in 3 emergency departments over a 1-year period was conducted. Scans were divided by body part and the most common indications for each type of scan were determined. Clinical outcomes from each study were extracted from final interpretations by the reporting radiologist.ResultsA total of 4556 CT scans were performed in the emergency department over a 1-year period. A total of 3.6% of all-comers to our emergency departments underwent CT scan as part of their investigation. There were 2107 head CTs (46%), 1296 (28%) abdominal CTs, 468 (10%) CTs of the chest, 408 (9%) CTs of the neck/spine, and 101 (2%) extremity CTs performed. The most common clinical indication for performing a CT head was focal neurological defect comprising 1534 (73%) of all CT heads. Twenty-four percent of abdominal CTs were for investigation of right lower quadrant pain, followed by flank pain (19%). Chest pain and shortness of breath were the most common indications for CTs of the chest (315 [75%]) with 10% of these examinations for this indication positive for pulmonary embolism. Trauma was the most common indication for neck CTs (296 [73%]) and extremities (70 [69%]). Nil acute was the most common final interpretation in all categories (79% CT heads, 75% neck CTs, 38% abdominal CTs, 43% chest CTs).ConclusionsNil acute was the most common diagnosis; however, serious clinical outcomes were identified 40% of the time. Cross-sectional imaging remains an integral tool for triage and diagnosis in this environment as the cost of missing a diagnosis in this setting has a great impact on patient care.     

Advances in Multidetector CT Diagnosis of Pediatric Pulmonary Thromboembolism

Although pediatric pulmonary thromboembolism is historically believed to be rare with relatively little information available in the medical literature regarding its imaging evaluation, it is more common than previously thought. Thus, it is imperative for radiologists to be aware of the most recent advances in its imaging information, particularly multidetector computed tomography (MDCT), the imaging modality of choice in the pediatric population. The overarching goal of this article is to review the most recent updates on MDCT diagnosis of pediatric pulmonary thromboembolism.     

急诊科一期手术治疗多发伤探讨（附154例报告）

目的：探讨在急诊科开展多发伤一期手术治疗的优越性．方法：采用ｔ检验方法分析比较一期手术治疗多发伤１５４例与分期治疗５６例的死亡率、住院时间等．结果：一期手术治疗组死亡率为８．４％，住院时间为（１５．２±８．１）天，治愈１４１例．分期手术治疗组死亡率为１４．３％，住院时间为（２７．４±８．９）天，治愈４８例．两组比较有显著性差异．结论：急诊科开展多发伤一期手术治疗可减少并发症、降低死亡率、缩短住院时间，并能充分发挥急诊科的优势     

Response to Induction Therapy in Pediatric Hodgkin’s Lymphoma: Performance of First-Order Texture Parameters of CT Images

Objectives:The aim of this study was to examine whether texture analysis features on pretreatment contrast-enhanced CT images could predict adequate response (AR) or inadequate response (IR) after two cycles of chemotherapy in pediatric Hodgkin’s lymphoma (PHL).Materials and methods:This retrospective single-center study included 32 children and adolescents with HL. Texture analysis was independently performed by two radiologists using pretreatment CT scans. The mean gray level, standard deviation, entropy, kurtosis, and skewness were derived from pixel distribution histograms before and after spatial filtration ranging from two (fine texture) to six (coarse texture). Interobserver reliability was studied using interobserver correlation coefficients (ICCs) to select texture parameters. Relationships between early response assessment (ERA) to induction therapy and associated factors were studied using Student’s t-tests and a lasso penalized logistic regression analysis.Results:Of the 32 patients, IR was observed in 13 and AR in 19. Inter-reader agreement was good to excellent (ICC > 0.75) for all parameters except skewness and kurtosis without filtration and at spatial scale filtration (SSF) = 2. These parameters were excluded from the analysis. The t-test identified only entropy at SSF = 2 (p value = 0.039) as a potential predictor of ERA. No parameters were significantly associated with ERA, according to a lasso penalized logistic regression.Conclusion:No textural parameters were identified as predictors of ERA after two cycles of chemotherapy in PHL.     

CT for trauma to the base of the skull and spine in children

Summary Five patients have been selected to demonstrate the diagnostic accuracy of CT in cases of traumatic damage to the base of the skull and spine in infants and children. CT is superior to any other diagnostic radiological technique as bone and soft tissues are usually equally well demonstrated during one visit to the Radiology Department. Thus, CT is considered to be the primary investigative procedure of choice to evaluate trauma of the base of the skull and spine in infants and children.     

ECG-gated chest CT angiography with 64-MDCT and tri-phasic IV contrast administration regimen in patients with acute non-specific chest pain

The purpose of this study was to evaluate chest CTA protocol using retrospective ECG-gating and triphasic IV contrast regimen for comprehensive evaluation of patients with acute non-specific chest pain. ECG-triggered dose modulation was used with a 64-MDCT scanner in 56 non-critically ill patients with acute nonspecific chest pain using triphasic IV regimen: 50 ml contrast followed by 50 ml 60% contrast/saline and 30 ml normal saline. Lungs, aorta, pulmonary and coronary arteries were graded on a 5-point scale (5, best). Aorta and pulmonary artery attenuation was measured and three coronary artery groups were evaluated. Comparison with invasive coronary angiography was obtained in nine patients on a per segment (16 total) basis. Dosimetry values were obtained. Studies were satisfactory in all patients (score >3). Aorta and pulmonary artery attenuation was >200 HU in 90.5%. Lung or pleura, non-cardiac vascular and coronary arteries disease were detected in 20, 11 and 16 patients, respectively. Median coronary angiography (grade 5) was significantly higher than acceptable for diagnosis grade 4 (p < 0.001). Per segment, weighted kappa statistic was 0.79 indicating substantial agreement with catheter angiography (p<0.001). Average DLP was 1,490 ± 412 mGy-cm. Gated 64-MDCT angiography with triphasic IV contrast is a robust multipurpose technique for patients with acute non-specific chest pain. An erratum to this article can be found at     

Establishment of Local Diagnostic Reference Levels of Pediatric Abdominopelvic and Chest CT Examinations Based on the Body Weight and Size in Korea

ObjectiveThe purposes of this study were to analyze the radiation doses for pediatric abdominopelvic and chest CT examinations from university hospitals in Korea and to establish the local diagnostic reference levels (DRLs) based on the body weight and size.Materials and MethodsAt seven university hospitals in Korea, 2494 CT examinations of patients aged 15 years or younger (1625 abdominopelvic and 869 chest CT examinations) between January and December 2017 were analyzed in this study. CT scans were transferred to commercial automated dose management software for the analysis after being de-identified. DRLs were calculated after grouping the patients according to the body weight and effective diameter. DRLs were set at the 75th percentile of the distribution of each institution''s typical values.ResultsFor body weights of 5, 15, 30, 50, and 80 kg, DRLs (volume CT dose index [CTDI_vol]) were 1.4, 2.2, 2.7, 4.0, and 4.7 mGy, respectively, for abdominopelvic CT and 1.2, 1.5, 2.3, 3.7, and 5.8 mGy, respectively, for chest CT. For effective diameters of < 13 cm, 14–16 cm, 17–20 cm, 21–24 cm, and > 24 cm, DRLs (size-specific dose estimates [SSDE]) were 4.1, 5.0, 5.7, 7.1, and 7.2 mGy, respectively, for abdominopelvic CT and 2.8, 4.6, 4.3, 5.3, and 7.5 mGy, respectively, for chest CT. SSDE was greater than CTDI_vol in all age groups. Overall, the local DRL was lower than DRLs in previously conducted dose surveys and other countries.ConclusionOur study set local DRLs in pediatric abdominopelvic and chest CT examinations for the body weight and size. Further research involving more facilities and CT examinations is required to develop national DRLs and update the current DRLs.     

Epidemiology and Severity of Sports and Recreation Injuries Presenting to a Tertiary Adult Emergency Department

Objective: This study aims to evaluate all sports and recreation injuries that present to an emergency department, identify the activity and injury patterns associated with hospital admission, and determine injuries that could be better treated in alternative care settings.

Methods: This is a retrospective review of all sports injuries that presented to the emergency department of a high volume, urban, tertiary referral center from 1/1/2010 to 12/31/2011. These were identified by a sports term search algorithm applied to all emergency department records. The main outcome measured was hospital admission status after sports injury. Univariate and multivariate regression analysis was performed to identify risk factors for hospital admission in the sports injury population.

Results: 1,101 of the 191,259 encounters (0.6%) had 1,210 sports injuries. 84 were admitted (7.6%). Basketball injuries were most prevalent (31.6%). All-terrain vehicle (ATV) related injuries was most often admitted (46.4%). Logistic regression identified ATV riding (95% CI 6.15–23.37, p < 0.001) and age over 50 years-old (4.09–17.40, p < 0.001) as independent risk factors for admission while basketball (0.101–0.985, p = 0.047) and black race (0.17–0.77, p = 0.008) were independently protective. Isolated sprains/strains and soft tissue injuries (4/649, 0.6%) rarely required admission.

Conclusions: The 7.6% admission rate is higher than previously reported, likely because the study institution is a tertiary referral center. ATV riding is associated with higher severity injuries that are more likely to require hospital admission. Most sports injuries that present to an emergency department, specifically isolated soft tissue injuries of the extremities, may be more efficiently treated in a non-emergent setting.     

Efficacy of Barium-Based Fecal Tagging for CT Colonography: a Comparison between the Use of High and Low Density Barium Suspensions in a Korean Population - a Preliminary Study

Objective

This preliminarily study was designed to determine and to compare the efficacy of two commercially available barium-based fecal tagging agents for CT colonography (CTC) (high-density [40% w/v] and low-density [4.6% w/v] barium suspensions) in a population in Korea.

Materials and Methods

In a population with an identified with an average-risk for colorectal cancer, 15 adults were administered three doses of 20 ml 40% w/v barium for fecal tagging (group I) and 15 adults were administered three doses of 200 ml 4.6% w/v barium (group II) for fecal tagging. Excluding five patients in group I and one patient in group II that left the study, ten patients in group I and 14 patients in group II were finally included in the analysis. Two experienced readers evaluated the CTC images in consensus regarding the degree of tagging of stool pieces 6 mm or larger. Stool pieces were confirmed with the use of standardized CTC criteria or the absence of matched lesions as seen on colonoscopy. The rates of complete fecal tagging were analyzed on a per-lesion and a per-segment basis and were compared between the patients in the two groups.

Results

Per-lesion rates of complete fecal tagging were 52% (22 of 42; 95% CI, 37.7-66.6%) in group I and 78% (28 of 36; 95% CI, 61.7-88.5%) in group II. The difference between the two groups did not reach statistical significance (p = 0.285). The per-segment rates of complete tagging were 33% (6 of 18; 95% CI, 16.1%-56.4%) in group I and 60% (9 of 15; 95% CI, 35.7%-80.3%) in group II; again, the difference between the two groups did not reach statistical significance (p = 0.171).

Conclusion

Barium-based fecal tagging using both the 40% w/v and the 4.6% w/v barium suspensions showed moderate tagging efficacy. The preliminary comparison did not demonstrate a statistically significant difference in the tagging efficacy between the use of the two tagging agents, despite the tendency toward better tagging with the use of the 4.6% w/v barium suspension.     

CT appearance of the spleen following conservative management of traumatic injury

Objective: To describe the long-term changes in the traumatized spleen following conservative management in pediatric patients. Methods: Between 1991 and 1997, 92 children were imaged with splenic trauma. The study population includes the 25 boys and 11 girls with follow-up computed tomography (CT) imaging at our institution. The follow-up CT studies were evaluated to determine the evolution of splenic injury. Results: On initial CT there were 6 grade I, 12 grade II, 9 grade III, and 9 grade IV–V splenic injuries. In follow-up 11 spleens were normal (30 %), including at least one in each grade of severity of injury. Splenic abnormalities were identified on follow-up in 25 children. These findings comprised clefts in 8 children, small cysts in 4, and devascularized segments involving less than 1 cm³ in 6, 1–2 cm³ in 2, and 2–4 cm³ in 5 children. Conclusions: All grades of splenic injury can resolve completely on subsequent CT imaging. In this series 30 % of patients had a normal follow-up CT. The most common persistent abnormalities included clefts and devascularized areas less than 4 cm³.     

Coronary CT angiography for acute chest pain in the emergency department

Acute chest pain in the emergency department (ED) is a common and costly public health challenge. The traditional strategy of evaluating acute chest pain by hospital or ED observation over a period of several hours, serial electrocardiography and cardiac biomarkers, and subsequent diagnostic testing such as physiologic stress testing is safe and effective. Yet this approach has been criticized for being time intensive and costly. This review evaluates the current medical evidence which has demonstrated the potential for coronary CT angiography (CTA) assessment of acute chest pain to safely reduce ED cost, time to discharge, and rate of hospital admission. These benefits must be weighed against the risk of ionizing radiation exposure and the influence of ED testing on rates of downstream coronary angiography and revascularization. Efforts at radiation minimization have quickly evolved, implementing technology such as prospective electrocardiographic gating and high pitch acquisition to significantly reduce radiation exposure over just a few years. CTA in the ED has demonstrated accuracy, safety, and the ability to reduce ED cost and crowding although its big-picture effect on total hospital and health care system cost extends far beyond the ED. The net effect of CTA is dependent also on the prevalence of coronary artery disease (CAD) in the population where CTA is used, which significantly influences rates of post-CTA invasive procedures such as angiography and coronary revascularization. These potential costs and benefits will warrant careful consideration and prospective monitoring as additional hospitals continue to implement this important technology into their diagnostic regimen.     

CT Pulmonary Angiography: Using Decision Rules in the Emergency Department

PurposeThe aim of this study was to assess the appropriateness of utilization and diagnostic yields of CT pulmonary angiography (CTPA), comparing two commonly applied decision rules, the pulmonary embolism (PE) rule-out criteria (PERC) and the modified Wells criteria (mWells), in the emergency department (ED) setting.MethodsInstitutional review board approval was obtained for this HIPAA-compliant, prospective–cohort, academic single-center study. Six hundred two consecutive adult ED patients undergoing CTPA for suspected PE formed the study population. The outcome was positive or negative for PE by CTPA and at 6-month follow-up. PERC and mWells scores were calculated. A positive PERC score was defined as meeting one or more criteria and a positive mWells score as >4. The percentage of CT pulmonary angiographic examinations that could have been avoided and the diagnostic yield of CTPA using PERC, mWells, and PERC applied to a negative mWells score were calculated.ResultsThe diagnostic yield of CTPA was 10% (61 of 602). By applying PERC, mWells, and PERC to negative mWells score, 17.6% (106 of 602), 45% (273 of 602), and 17.1% (103 of 602) of CT pulmonary angiographic examinations, respectively, could have been avoided. The diagnostic yield in PERC-positive patients was higher than in mWells-positive patients (10% [59 of 602] vs 8% [49 of 602], P < .0001). Among PERC-negative and mWells-negative patients, the diagnostic yields for PE were 1.9% (2 of 106) and 4% (12 of 273), respectively (P = .004). The diagnostic yield of a negative PERC score applied to a negative mWells score was 1.9% (2 of 103).ConclusionsThe use of PERC in the ED has the potential to significantly reduce the utilization of CTPA and misses fewer cases of PE compared with mWells, and it is therefore a more efficient decision tool.     

Accuracy of CT during arterial portography in the segmental localisation of liver tumours

Preoperative computed tomography during arterial portography (CTAP) of the liver was performed in 7 patients with 20 malignant liver tumours. CTAP proved accurate for segmental localization of detected lesions (91% accuracy), but had low overall sensitivity (57%) with 10 lesions being less than less in diameter. Correspondence to: R. F. Mcloughlin