Spectrum of computed tomography manifestations of appendiceal neoplasms: acute appendicitis and beyond.
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ABSTRACT:
SUBMITTER: Karande GY
PROVIDER: S-EPMC6482419 | biostudies-literature | 2019 Apr
REPOSITORIES: biostudies-literature
Publications
Spectrum of computed tomography manifestations of appendiceal neoplasms: acute appendicitis and beyond.
Karande Gita Yashwantrao GY Chua Wei Ming WM Yiin Raphael Shih Zhu RSZ Wong Kang Min KM Hedgire Sandeep S Tan Tien Jin TJ
Singapore medical journal 20190401 4
Appendiceal neoplasms are rare and often only discovered incidentally during surgery performed for acute appendicitis. Computed tomography (CT) has been demonstrated to be a reliable technique for accurately establishing the preoperative diagnosis of appendiceal neoplasms that manifest as acute appendicitis through the presence of certain imaging findings. Other manifestations of appendiceal neoplasms include appendiceal mass, mucocoele, localised abscess formation, ileus, increasing abdominal g ...[more]
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Project description:ObjectiveTo identify the CT findings associated with treatment failure after antibiotic therapy for acute appendicitis.Materials and methodsAltogether, 198 patients who received antibiotic therapy for appendicitis were identified by searching the hospital's surgery database. Selection criteria for antibiotic therapy were uncomplicated appendicitis with an appendiceal diameter equal to or less than 11 mm. The 86 patients included in the study were divided into a treatment success group and a treatment failure group. Treatment failure was defined as a resistance to antibiotic therapy or recurrent appendicitis during a 1-year follow-up period. Two radiologists independently evaluated the following CT findings: appendix-location, involved extent, maximal diameter, thickness, wall enhancement, focal wall defect, periappendiceal fat infiltration, and so on. For the quantitative analysis, two readers independently measured the CT values at the least attenuated wall of the appendix by drawing a round region of interest on the enhanced CT (HUpost) and non-enhanced CT (HUpre). The degree of appendiceal wall enhancement (HUsub) was calculated as the subtracted value between HUpost and HUpre. A logistic regression analysis was used to identify the CT findings associated with treatment failure.ResultsSixty-four of 86 (74.4%) patients were successfully treated with antibiotic therapy, with treatment failure occurring in the remaining 22 (25.5%). The treatment failure group showed a higher frequency of hypoenhancement of the appendiceal wall than the success group (31.8% vs. 7.8%; p = 0.005). Upon quantitative analysis, both HUpost (46.7 ± 21.3 HU vs. 58.9 ± 22.0 HU; p = 0.027) and HUsub (26.9 ± 17.3 HU vs. 35.4 ± 16.6 HU; p = 0.042) values were significantly lower in the treatment failure group than in the success group.ConclusionHypoenhancement of the appendiceal wall was significantly associated with treatment failure after antibiotic therapy for acute appendicitis.
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Project description:BackgroundUncomplicated and complicated acute appendicitis seem to be two different forms of this common abdominal emergency. The contribution of appendiceal microbiota to appendicitis pathogenesis has been suggested, but differences between uncomplicated and complicated appendicitis are largely unknown. We compared the appendiceal microbiota in uncomplicated and complicated acute appendicitis.MethodsThis prospective single-center clinical cohort study was conducted as part of larger multicenter MAPPAC trial enrolling adult patients with computed tomography or clinically confirmed uncomplicated or complicated acute appendicitis. The microbial composition of the appendiceal lumen was determined using 16S rRNA gene amplicon sequencing.ResultsBetween April 11, 2017, and March 29, 2019, 118 samples (41 uncomplicated and 77 complicated appendicitis) were available. After adjusting for age, sex, and BMI, alpha diversity in complicated appendicitis was higher (Shannon p = 0.011, Chao1 p = 0.006) compared to uncomplicated appendicitis. Microbial compositions were different between uncomplicated and complicated appendicitis (Bray-Curtis distance, P = 0.002). Species poor appendiceal microbiota composition with specific predominant bacteria was present in some patients regardless of appendicitis severity.ConclusionUncomplicated and complicated acute appendicitis have different appendiceal microbiome profiles further supporting the disconnection between these two different forms of acute appendicitis.Study registrationClinicalTrials.gov NCT03257423.
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Project description:ObjectivesTo determine the prevalence of clinically relevant unrequested extra-cardiac imaging findings on cardiac Computed Tomography (CT) and explanatory factors thereof.MethodsA systematic review of studies drawn from online electronic databases followed by meta-analysis with meta-regression was performed. The prevalence of clinically relevant unrequested findings and potentially explanatory variables were extracted (proportion of smokers, mean age of patients, use of full FOV, proportion of men, years since publication).ResultsNineteen radiological studies comprising 12922 patients met the inclusion criteria. The pooled prevalence of clinically relevant unrequested findings was 13% (95% confidence interval 9-18, range: 3-39%). The large differences in prevalence observed were not explained by the predefined (potentially explanatory) variables.ConclusionsClinically relevant extra-cardiac findings are common in patients undergoing routine cardiac CT, and their prevalence differs substantially between studies. These differences may be due to unreported factors such as different definitions of clinical relevance and differences between populations. We present suggestions for basic reporting which may improve the interpretability and comparability of future research.
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