Study Type
Study Type
Study Objective(Purpose of Study)
Study Objective(Purpose of Study)
Study Results
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Study Quality
1. Glass CC, Rangel SJ. Overview and diagnosis of acute appendicitis in children. [Review]. Semin Pediatr Surg. 25(4):198-203, 2016 Aug. Review/Other-Dx N/A To review the predictive utility for presenting signs and symptoms, laboratory tests, and imaging studies in the diagnostic work-up of appendicitis. No results stated in abstract. 4
2. Tseng P, Berdahl C, Kearl YL, et al. Does Right Lower Quadrant Abdominal Ultrasound Accurately Identify Perforation in Pediatric Acute Appendicitis?. J Emerg Med. 50(4):638-42, 2016 Apr. Observational-Dx 144 patients To determine the sensitivity of right lower quadrant abdominal ultrasound (RLQUS) to identify perforation in pediatric patients with appendicitis. Of the 539 patients evaluated for appendicitis, 144 (26.7%) patients had appendicitis, and 40 of these (27.8%) were perforated. Thirty-nine had RLQUS performed as part of their evaluation. Of these, 28 had positive findings for appendicitis, and 9 were read as definite or possible perforated appendicitis. The sensitivity of RLQUS for the diagnosis of appendicitis in the group with perforation was 77.1% (95% confidence interval [CI], 59.4-89%) and the sensitivity for diagnosing a perforation was 23.1% (95% CI, 11.1-39.3%). 3
3. Larson DB, Trout AT, Fierke SR, Towbin AJ. Improvement in diagnostic accuracy of ultrasound of the pediatric appendix through the use of equivocal interpretive categories. AJR Am J Roentgenol. 204(4):849-56, 2015 Apr. Observational-Dx 1357 examinations To evaluate the diagnostic performance of ultrasound of the pediatric appendix using standardized structured reports that incorporate equivocal interpretive categories. One thousand three hundred fifty-seven examinations were included, with appendicitis present in 16.9% (230/1357) of cases. The appendix was visualized in 47.2% (641/1357) of cases, with interpretations as follows: positive, 27.5% (176/641); intermediate likelihood, 9.7% (62/641); and normal, 62.9% (403/641). The appendicitis rate in each group was 92.6% (163/176), 25.8% (16/62), and 0.5% (2/403), respectively. The appendix was not visualized in 52.8% (716/1357) of cases, with secondary findings identified in 8.5% (61/716) and no secondary findings in 91.5% (655/716) of cases. The appendicitis rate was 39.3% (24/61) and 3.8% (25/655) in these groups, respectively. Appendicitis was present in 32.5% of equivocal (intermediate likelihood and not visualized, secondary findings) cases and 2.6% of negative (normal and not visualized, no secondary findings) cases. Diagnostic accuracy of a five-category scheme was 96.8% versus 94.1% for a binary scheme. 3
4. Kharbanda AB, Stevenson MD, Macias CG, et al. Interrater reliability of clinical findings in children with possible appendicitis. Pediatrics. 129(4):695-700, 2012 Apr. Observational-Dx 811 patients To determine the interrater reliability of clinical history and physical examination findings in children undergoing evaluation for possible appendicitis in a large, multicenter cohort. A total of 811 patients had 2 assessments completed, and 599 (74%) had 2 assessments completed within 60 minutes. Seventy-five percent of paired assessments were completed by pediatric emergency physicians. Raw agreement ranged from 64.9% to 92.3% for history variables and 4 of 6 variables had moderate interrater reliability (kappa > .4). The highest kappa values were noted for duration of pain (kappa = .56 [95% confidence intervals .51-.61]) and history of emesis (.84 [.80-.89]). For physical examination variables, raw agreement ranged from 60.9% to 98.7%, with 4 of 8 variables exhibiting moderate reliability. Among physical examination variables, the highest kappa values were noted for abdominal pain with walking, jumping, or coughing (.54 [.45-.63]) and presence of any abdominal tenderness on examination (.49 [.19-.80]). 2
5. Nance ML, Adamson WT, Hedrick HL. Appendicitis in the young child: a continuing diagnostic challenge. Pediatr Emerg Care. 16(3):160-2, 2000 Jun. Review/Other-Dx 120 patients To examine the presenting signs and symptoms of children 5 years of age or less who underwent operation for appendicitis. For the 11-year period, 120 patients 5 years of age or less required an operation for appendicitis and had a complete medical database. The mean age was 3.6 +/- 1.3 years; 53% were male. Patients underwent a separate medical evaluation prior to arriving at a definitive diagnosis in 44.2 % cases. The most common presenting symptom was abdominal pain (94%); the most common sign was abdominal tenderness (95.8%). Tenderness was generally diffuse if perforation had occurred (62%) or focal in the nonperforated group (61%). The duration of symptoms in patients with perforation was more than double that of the nonperforated patients (4.7 vs 2.1 days, respectively). The mean white blood cell count (WBC) was 18.3 +/- 7.4 cells/mm3, and did not differ significantly between the perforated and nonperforated groups. A left shift detected in the WBC differential was present in 91%. An abdominal radiograph was obtained in 87%, and demonstrated a fecalith in 18%. A preoperative ultrasound was obtained in 38%, a computed tomographic scan in 7%. At the time of surgery, 74% were found to have evidence of perforation. An abscess was found at the initial surgery in 47% of patients with appendiceal perforation, but in no patient in whom perforation had not occurred. The rate of perforation increased as the age of the patient decreased (100% perforation for age 1 (n = 10) to 69% for age 5, (n = 35). Perforation was associated with a longer hospital length of stay as compared to the nonperforated appendix (median 9 days vs. 3 days, respectively, P < 0.001). There were no deaths in this series. 4
6. Bonadio W, Peloquin P, Brazg J, et al. Appendicitis in preschool aged children: Regression analysis of factors associated with perforation outcome. J Pediatr Surg. 50(9):1569-73, 2015 Sep. Observational-Dx 1922 children To determine the significance of clinical variables for perforation outcome of a large series of preschool aged children with appendicitis. This age group accounted for only 9% of all cases of pediatric appendicitis at our institution during the study period. Perforation rate was inversely proportional to patient age, occurring in 100% aged<1 year, 91% ages 1-2 years, 76% ages 2-3 years, 73% ages 3-4 years, and 57% ages 4-5 years. Risk for perforation increased proportionately with duration of symptoms, ranging from 48% when<1 day vs 84% when>1 day; and 93% when>2 days. One-quarter with perforation had a prior recent medical evaluation with an alternative diagnosis rendered preappendicitis diagnosis. The mean duration of hospitalization was four times longer in those with perforation [8 days] vs no perforation [2 days]. Univariate analysis showed each of the following factors was significantly associated with perforation outcome: younger patient age, female gender, prior medical visit<48 hours of appendicitis diagnosis, symptom duration, presence of fever, and presence of appendicolith. Multivariate logistic regression combining all significant univariate predictors showed only duration of symptoms and presence of appendicolith were significantly associated with perforation outcome; receiver-operating characteristic curves are generated to evaluate the predictive accuracy of these two factors, both individually and when combined. 3
7. Bachur RG, Hennelly K, Callahan MJ, Chen C, Monuteaux MC. Diagnostic imaging and negative appendectomy rates in children: effects of age and gender. Pediatrics. 129(5):877-84, 2012 May. Observational-Dx 8,959,155 visits at 40 pediatric emergency departments; 55,227 children To examine the use of CT and US for age and gender subgroups of children undergoing an appendectomy and to study the association between imaging and negative appendectomy rates (NARs) among these subgroups. The negative appendectomy rate was 3.6%. Negative appendectomy rates were highest for children <5 years (boys 16.8%, girls 14.6%) and girls >10 years (4.8%). At the institutional level, increased rates of diagnostic imaging (US and/or CT) were associated with lower negative appendectomy rates for all age and gender subgroups other than children <5 years. The negative appendectomy rates was 1.2% for boys >5 years without any diagnostic imaging. 3
8. Hendriks IG, Langen RM, Janssen L, Verrijth-Wilms IM, Wouda S, Janzing HM. Does the Use of Diagnostic Imaging Reduce the Rate of Negative Appendectomy?. Acta Chir Belg. 115(6):393-6, 2015 Nov-Dec. Review/Other-Dx N/A To provide guidelines for the diagnosis and treatment of acute appendicitis. A significant decline in the percentage of negative appendectomies was found from an average of 18.0% before implementation of the guideline towards an average of 9.2% after implementation of the guideline (p<0.001). The percentage of patients with appendicitis in which the appendix perforated remained about the same; 20.9% before implementation of the guideline compared to 19.2% after implementation of the guideline (p=0.527). 4
9. Mariadason JG, Wang WN, Wallack MK, Belmonte A, Matari H. Negative appendicectomy rate as a quality metric in the management of appendicitis: impact of computed tomography, Alvarado score and the definition of negative appendicectomy. Ann R Coll Surg Engl. 94(6):395-401, 2012 Sep. Observational-Dx 1,306 charts To examine the impact of Computed Tomography (CT), Alvarado score and definition on the negative appendicectomy rate (NAR). When the definition of negative appendicectomy was changed, the NAR rose from 9.2% to 15.8% (p=0.0097) for Cohort A, from 2.8% to 8.6% (p=0.0180) for Cohort B (CT rate: 80.6%) and from 3.0% to 6.7% (p=0.0255) for Cohort C (CT rate: 92.4%). The introduction of CT lowered NAR with stringent (NAR-STD) from 1996-2000 (9.2%) to 2001-2010 (2.9%) but increasing the CT rate from 2001-2010 had no impact on the NAR. The positive predictive value for Alvarado score (98.60%) and CT (99.03%) were similar. 3
10. Pastore V, Cocomazzi R, Basile A, Pastore M, Bartoli F. Limits and advantages of abdominal ultrasonography in children with acute appendicitis syndrome. Afr J Paediatr Surg. 11(4):293-6, 2014 Oct-Dec. Observational-Dx 480 children To evaluate its contribution to the diagnosis of acute appendicitis during the period 2010-2013. Acute appendicitis was confirmed in 188 operated patients while no one in the non-operated group returned to the hospital or was operated for appendicitis. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 79%, 78%, 95%, 39% and 79%, respectively. Negative appendectomy and perforation rates were 14% and 8%. Seventeen children in the operated group required a second diagnostic imaging: 7 CTs and 10 USs. All the seven CTs were consistent with appendicitis and 6 out of 10 USs showed ecographic signs of appendicitis. 3
11. Golden SK, Harringa JB, Pickhardt PJ, et al. Prospective evaluation of the ability of clinical scoring systems and physician-determined likelihood of appendicitis to obviate the need for CT. Emerg Med J. 33(7):458-64, 2016 Jul. Observational-Dx 287 subjects To determine whether clinical scoring systems or physician gestalt can obviate the need for computed tomography (CT) in patients with possible appendicitis. Of the 287 patients (mean age (range), 31 (12-88) years; 60% women), the prevalence of appendicitis was 33%. The Alvarado score had a positive likelihood ratio (LR(+)) (95% CI) of 2.2 (1.7 to 3) and a negative likelihood ratio (LR(-)) of 0.6 (0.4 to 0.7). The modified Alvarado score (MAS) had LR(+) 2.4 (1.6 to 3.4) and LR(-) 0.7 (0.6 to 0.8). The Raja Isteri Pengiran Anak Saleha Appendicitis (RIPASA) score had LR(+) 1.3 (1.1 to 1.5) and LR(-) 0.5 (0.4 to 0.8). Physician-determined likelihood of appendicitis had LR(+) 1.3 (1.2 to 1.5) and LR(-) 0.3 (0.2 to 0.6). When combined with physician likelihoods, LR(+) and LR(-) was 3.67 and 0.48 (Alvarado), 2.33 and 0.45 (RIPASA), and 3.87 and 0.47 (MAS). The area under the curve was highest for physician-determined likelihood (0.72), but was not statistically significantly different from the clinical scores (RIPASA 0.67, Alvarado 0.72, MAS 0.7). 3
12. Lietzen E, Ilves I, Salminen P, et al. Clinical and laboratory findings in the diagnosis of right lower quadrant abdominal pain: outcome analysis of the APPAC trial. Clin Chem Lab Med. 54(10):1691-7, 2016 Oct 01. Experimental-Dx 970 patients To improve the diagnostics and to clarify to whom antibiotic treatment might be the treatment of choice. Computed tomography (CT) confirmed the diagnosis of acute appendicitis in 73% (n=970) and in 27% (n=351) it revealed no or other diagnosis. Acute appendicitis patients had significantly higher white blood cell count (WBC) levels than patients without appendicitis (median 12.2 and 10.0, respectively, p<0.0001), whereas C-reactive protein (CRP) levels did not differ between the two groups. Ideal cut-off points were assessed with receiver operating characteristic (ROC) curves, but neither these markers or neither their combination nor any clinical characteristic could accurately differentiate between patients with acute appendicitis and those without. The proportion of patients with normal WBC count and C-reactive protein (CRP) was significantly (p=0.0007) lower in patients with acute appendicitis than in patients without appendicitis. 2
13. Saucier A, Huang EY, Emeremni CA, Pershad J. Prospective evaluation of a clinical pathway for suspected appendicitis. Pediatrics. 133(1):e88-95, 2014 Jan. Observational-Dx 196 patients To evaluate the diagnostic accuracy of a clinical pathway for suspected appendicitis combining the Samuel's pediatric appendicitis score (PAS) and selective use of ultrasonography (US) as the primary imaging modality. Of the 196 patients enrolled, 65 (33.2%) had appendicitis. An initial PAS of 1-3 was noted in 44 (22.4%), 4-7 in 119 (60.7%), and 8-10 in 33 (16.9%) patients. Ultrasonography was performed in 128 (65.3%) patients, and 48 (37.5%) were positive. An abdominal computed tomography scan was requested by the surgical consultants in 13 (6.6%) patients. The negative appendectomy rate was 3 of 68 (4.4%). Follow-up was established on 190 of 196 (96.9%) patients. Overall diagnostic accuracy of the pathway was 94% (95% confidence interval [CI] 91%-97%) with a sensitivity of 92.3% (95% CI 83.0%-97.5%), specificity of 94.7% (95% CI 89.3%-97.8%), likelihood ratio (+) 17.3 (95% CI 8.4-35.6) and likelihood ratio (-) 0.08 (95% CI 0.04-0.19). 3
14. Tan WJ, Acharyya S, Goh YC, et al. Prospective comparison of the Alvarado score and CT scan in the evaluation of suspected appendicitis: a proposed algorithm to guide CT use. J Am Coll Surg. 220(2):218-24, 2015 Feb. Observational-Dx 350 patients To compare the performance statistics of the Alvarado Score (AS) with those of computed tomography (CT) scan in the evaluation of suspected appendicitis, with the aim of identifying a subset of patients who will benefit from CT evaluation. The study included 134 males (38.3%) and 216 females (61.7%). The overall prevalence of appendicitis was 44.3% in the total study population; 37.5% in females and 55.2% in males. There were 168 patients (48%) who underwent surgery, with a negative appendectomy rate of 7.7%. Positive likelihood ratio of disease was significantly greater than 1 only in patients with an AS of 4 and above. An AS of 7 and above in males and 9 and above in females has a positive likelihood ratio comparable to that of CT scan. 2
15. Athans BS, Depinet HE, Towbin AJ, Zhang Y, Zhang B, Trout AT. Use of Clinical Data to Predict Appendicitis in Patients with Equivocal US Findings. Radiology. 280(2):557-67, 2016 Aug. Observational-Dx 776 patients To determine the incremental value of clinical data in patients with ultrasonographic (US) examinations that were interpreted as being equivocal for acute appendicitis. The study population was made up of 776 patients (mean age, 11.7 years +/- 3.7), with 429 (55.2%) girls. A total of 203 (26%) patients had appendicitis. US had a negative predictive value of 96.2% and a positive predictive value of 93.3% for depicting appendicitis, with 89 of 782 (11.4%) equivocal examinations. Categoric PAS and Alvarado scores were equivocal for 59.5% (53 of 89) and 50.6% (45 of 89) of equivocal US examinations, respectively. Categoric low- and high-likelihood PAS and Alvarado scores correctly predicted the presence of appendicitis in 61.1% (22 of 36) and 77.3% (34 of 44) of equivocal US examinations, respectively. As continuous variables, a PAS or Alvarado score of 5 or lower could be used to exclude appendicitis, with a 80.8% (21 of 26) and 90% (18 of 20) negative predictive value, respectively. 3
16. Fleischman RJ, Devine MK, Yagapen MA, et al. Evaluation of a novel pediatric appendicitis pathway using high- and low-risk scoring systems. Pediatr Emerg Care. 29(10):1060-5, 2013 Oct. Observational-Dx 178 patients To determine the test characteristics of a pathway for pediatric appendicitis and its effects on emergency department (ED) length of stay, imaging, and admissions. Appendicitis was diagnosed in 65 of 178 patients. Of those with appendicitis, 63 were not low-risk (sensitivity, 96.9%; specificity, 40.7%). The high-risk criteria had a sensitivity of 75.3% and specificity of 75.2%. We reviewed 292 visits before and 290 after the pathway implementation. Emergency department length of stay was similar (253 minutes before vs 257 minutes after, P = 0.77). Computed tomography was used in 12.7% of visits before and 6.9% of visits after (P = 0.02). Use of ultrasound was not significantly different (47.3% vs 53.7%). Admission rates were not significantly different (45.5% vs 42.7%) 2
17. Rezak A, Abbas HM, Ajemian MS, Dudrick SJ, Kwasnik EM. Decreased use of computed tomography with a modified clinical scoring system in diagnosis of pediatric acute appendicitis. Arch Surg. 146(1):64-7, 2011 Jan. Observational-Dx 59 patients To determine the Alvarado score for each patient and correlated it with the pathological findings and imaging studies to evaluate the efficacy of computed tomography (CT) and its attendant radiation exposure. The standard Alvarado score for acute appendicitis had a sensitivity of 92% and a specificity of 82%, with an accuracy of 92%. In the modified Alvarado scoring system, CT findings were substituted for Alvarado scores in the ranges of 5 or 6, 5 to 7, 5 to 8, and 5 to 9. The modification resulted in the greatest accuracy (98%) in diagnosing appendicitis in patients with scores in the range of 5 to 7. This modification theoretically would have decreased the use of CT by about 27% in this group of retrospectively studied patients. Furthermore, in patients with Alvarado scores of 1 to 4, another diagnosis should be considered; in patients with scores of 5 to 7, CT should be performed; and, in patients with scores of 8 to 10, an appendectomy should be performed promptly without further studies. 3
18. Santillanes G, Simms S, Gausche-Hill M, et al. Prospective evaluation of a clinical practice guideline for diagnosis of appendicitis in children. Acad Emerg Med. 19(8):886-93, 2012 Aug. Observational-Dx 475 patients To assess the performance of a clinical practice guideline for evaluation of possible appendicitis in children. A total of 475 patients were enrolled. Of those, 193 (41%) had appendicitis. No low-risk patient had appendicitis. Medium-risk patients had a 19% rate of appendicitis, and 83% of high-risk patients had appendicitis. Factors associated with an increased likelihood of appendicitis included decreased bowel sounds; rebound tenderness; and presence of psoas, obturator, or Rovsing's signs. Of the 475 patients, 276 (58%) were managed without a CT scan. Seventy-one of the 193 (37%) patients with appendicitis went to the operating room without any imaging. The rate of missed appendicitis was 2%, and the rate of negative appendectomy was 1%. 3
19. Trout AT, Sanchez R, Ladino-Torres MF, Pai DR, Strouse PJ. A critical evaluation of US for the diagnosis of pediatric acute appendicitis in a real-life setting: how can we improve the diagnostic value of sonography?. Pediatr Radiol. 42(7):813-23, 2012 Jul. Observational-Dx 246 cases To review the diagnostic performance of US in acute appendicitis with attention to factors that influence performance. The appendix was identified in 246/1,009 cases (24.4%), with identification increasing over time. The accuracy of US was 85-91% with 35 false-positives and 54 false-negatives. Pediatric sonographers were significantly better at identifying the appendix than non-pediatric sonographers (P < 0.0001). Increased weight was the only patient factor that influenced identification of the appendix (P = 0.006). CT use was stable over the 5 years but declined in cases where the appendix was identified by US. 3
20. Abo A, Shannon M, Taylor G, Bachur R. The influence of body mass index on the accuracy of ultrasound and computed tomography in diagnosing appendicitis in children. Pediatr Emerg Care. 27(8):731-6, 2011 Aug. Observational-Dx 176 patients To determine the relationship between BMI and accuracy of US and CT scan for suspected appendicitis. Over the study period, 176 patients with suspected appendicitis underwent US and/or CT. Mean age was 11.8 +/- 4.2 years; 42% were male. zBMI ranged from -2.78 to 2.75 (mean, 0.59); 70 children (40%) were overweight or obese; 73 (42%) had appendicitis. Ultrasound was performed on 147 (84%), and CT on 128 children (73%); 99 children (56%) had both studies. The overall sensitivity for US in diagnosing appendicitis was 38% (95% confidence interval [CI], 26%-52%) with a specificity of 97% (95% CI, 90%-99%). In the underweight/normal weight group, the sensitivity of US was 45% (95% CI, 27%-64%); in the overweight group, 35% (95% CI, 15%-61%), and in the obese group, 22% (95% CI, 4%-60%). The sensitivity and specificity of CT were 96% (95% CI, 86%-99%) and 97% (95% CI, 90%-100%) and did not vary by zBMI class. 3
21. Yigiter M, Kantarci M, Yalcin O, Yalcin A, Salman AB. Does obesity limit the sonographic diagnosis of appendicitis in children?. J Clin Ultrasound. 39(4):187-90, 2011 May. Observational-Dx 122 children To evaluate whether obesity has a negative impact on the ultrasound (US) visualization of the appendix in children clinically diagnosed with appendicitis. There was no statistical difference between the three groups with regard to the visualization of the appendix by US. Diagnostic accuracy of US was 90.4%, 80.5%, and 80% in group 1, group 2, and group 3, respectively. 3
22. Binkovitz LA, Unsdorfer KM, Thapa P, et al. Pediatric appendiceal ultrasound: accuracy, determinacy and clinical outcomes. Pediatr Radiol. 45(13):1934-44, 2015 Dec. Observational-Dx 452 girls; 338 boys To assess the impact of patient factors (gender, age, body mass index, and symptom duration) and system factors (call status or year of exam) on pediatric appendiceal ultrasound (US) accuracy and indeterminate study rate, to assess the impact of indeterminate study results on follow-up computed tomography (CT) and negative laparotomy rates and to present strategies to reduce the rate of indeterminate US studies and improve accuracy. A total of 790 US examinations were performed in 452 girls (57%) and 338 boys (43%). The prevalence of appendicitis was 18.5% (146/790). There were 109 true-positive, 440 true-negative, 17 false-positive, 6 false-negative, 218 equivocal and 41 technically inadequate US studies. A definitive interpretation was made in 72% of the studies, with an accuracy, sensitivity and specificity of 0.960, 0.948 and 0.963, respectively. No patient or system factors significantly affected US accuracy. Indeterminate studies (28%) had significantly higher CT utilization (46% vs. 11%) and normal appendectomy rates (6.9% vs. 3.5%). 3
23. Mittal MK, Dayan PS, Macias CG, et al. Performance of ultrasound in the diagnosis of appendicitis in children in a multicenter cohort. Acad Emerg Med. 20(7):697-702, 2013 Jul. Observational-Dx 2,625 patients To assess the test characteristics of ultrasound (US) in diagnosing appendicitis in children and to evaluate site-related variations based on the frequency of its use. Additionally, the authors assessed the test characteristics of US when the appendix was clearly visualized. Of 2,625 patients enrolled, 965 (36.8%) underwent abdominal US. US had an overall sensitivity of 72.5% (95% confidence interval [CI] = 58.8% to 86.3%) and specificity 97.0% (95% CI = 96.2% to 97.9%) in diagnosing appendicitis. US sensitivity was 77.7% at the three sites (combined) that used it in 90% of cases, 51.6% at a site that used it in 50% of cases, and 35% at the four remaining sites (combined) that used it in 9% of cases. US retained a high specificity of 96% to 99% at all sites. Of the 469 (48.6%) cases across sites where the appendix was clearly visualized on US, its sensitivity was 97.9% (95% CI = 95.2% to 99.9%), with a specificity of 91.7% (95% CI = 86.7% to 96.7%). 2
24. Peletti AB, Baldisserotto M. Optimizing US examination to detect the normal and abnormal appendix in children. Pediatr Radiol. 36(11):1171-6, 2006 Nov. Observational-Dx 107 children To optimize ultrasound (US) examination to detect the normal and the abnormal appendix according to the potential positions of the appendix. Of the 107 children examined, 56 had a histologic diagnosis of acute appendicitis. Sonography had a sensitivity of 100% and specificity of 98% for the diagnosis of appendicitis. A normal appendix was visualized in 44 (86.2%) of the 51 patients without acute appendicitis, and of these 44, 43 were true-negative and 1 was false-positive. Normal and abnormal appendices, respectively, were positioned as follows: 54.4% and 39.3% were mid-pelvic; 27.2% and 28.6% were retrocecal; 11.4% and 17.8% were deep pelvic; and 6.8% and 14.3% were abdominal. 3
25. Unlu C, de Castro SM, Tuynman JB, Wust AF, Steller EP, van Wagensveld BA. Evaluating routine diagnostic imaging in acute appendicitis. Int J Surg. 7(5):451-5, 2009 Oct. Observational-Dx 941 patients To evaluate the impact of selective imaging on clinical management of patients who present with symptoms suggesting acute appendicitis. In 650 (69%) patients with right lower quadrant pain, diagnosis was based on medical history, physical and laboratory examination only. The diagnostic accuracy was 84%. Another 291 patients (31%) underwent selective imaging reaching a diagnostic accuracy of 71%. Ultrasound was conducted in 277 patients (sensitivity: 59%; specificity: 91%). CT scan was conducted in 43 patients (sensitivity: 100%; specificity: 95%). 3
26. Cundy TP, Gent R, Frauenfelder C, Lukic L, Linke RJ, Goh DW. Benchmarking the value of ultrasound for acute appendicitis in children. J Pediatr Surg. 51(12):1939-1943, 2016 Dec. Observational-Dx 3799 ultrasound examinations To evaluate the diagnostic accuracy for a large series of consecutive unselected abdominal ultrasound examinations performed for clinical suspicion of acute appendicitis in children. A total of 3799 ultrasound examinations were evaluated. Mean age was 11.5+/-3.8years. The proportion of patients investigated with preoperative ultrasound was 59.9% (1103/1840). Appendix visualization rate was 91.7%. Overall diagnostic accuracy was 95.5%. Sensitivity and specificity values were 97.1% (95.9-98.1; 95% CI) and 94.8% (93.9-95.6; 95% CI), respectively. Separate analysis of only ultrasound positive and negative examinations (i.e., excluding nondiagnostic examinations) confirmed sensitivity and specificity values of 98.8% and 98.3%. 3
27. Elikashvili I, Tay ET, Tsung JW. The effect of point-of-care ultrasonography on emergency department length of stay and computed tomography utilization in children with suspected appendicitis. Acad Emerg Med. 21(2):163-70, 2014 Feb. Observational-Dx 150 patients To evaluate the effect of point-of-care (POC) ultrasonography (US) in children with suspected appendicitis and its effect on emergency department (ED) length of stay (LOS) and computed tomography (CT) utilization. Among 150 enrolled patients, 50 had appendicitis (33.3%). There were no missed cases of appendicitis in discharged patients at 3-week phone follow-up, nor negative laparotomies in those who went to the operating room. Those who had dispositions after POC US (n = 25) had a significantly decreased mean ED LOS (154 minutes, 95% confidence interval [CI] = 115 to 193 minutes) compared with those requiring radiology US (288 minutes, 95% CI = 257 to 319 minutes) or CT scan (487 minutes; 95% CI = 434 to 540 minutes). Baseline CT rate was 44.2% (95% CI = 30.7% to 57.7%) prior to study start and decreased to 27.3% (95% CI = 20.17% to 34.43%) during the study. CTs were avoided in four patients with conclusive POC US results and inconclusive radiology US results. The sensitivity, specificity, positive likelihood ratio (LR+), and negative likelihood ratio (LR-) for POC US were 60% (95% CI = 46% to 72%), 94% (95% CI = 88% to 97%), 10 (95% CI = 4 to 23), and 0.4 (95% CI = 0.3 to 0.6). For radiology US they were 63% (95% CI = 48% to 75%), 99% (95% CI = 94% to 99%), 94 (95% CI = 6 to 1,500), and 0.4 (95% CI = 0.3 to 0.6); and for CT they were 83% (95% CI = 58% to 95%), 98% (95% CI = 85% to 99%), 45 (95% CI = 3 to 707), and 0.2 (95% CI = 0.05 to 0.5). 2
28. Le J, Kurian J, Cohen HW, Weinberg G, Scheinfeld MH. Do clinical outcomes suffer during transition to an ultrasound-first paradigm for the evaluation of acute appendicitis in children?. AJR Am J Roentgenol. 201(6):1348-52, 2013 Dec. Observational-Dx 804 patients To examine whether the rate of complicated appendicitis and the hospital length of stay (LOS) increased during the transition to an ultrasound-first paradigm for the imaging evaluation of acute appendicitis. Eight hundred four patients met the inclusion criteria. The percentage of patients who underwent CT only showed a moderate downward association with year (rho = -0.32, p < 0.01), and the percentage of patients who underwent ultrasound first showed a moderate upward trend (rho = 0.44, p < 0.01). The percentage of patients with ultrasound as the only study performed before appendectomy increased moderately over the 7-year study period (rho = 0.33, p < 0.01). The percentage of patients with complicated appendicitis and the median hospital LOS did not increase significantly over the study duration (rho = -0.01, p = 0.74 and rho = -0.04, p = 0.25, respectively). 3
29. Doria AS, Moineddin R, Kellenberger CJ, et al. US or CT for Diagnosis of Appendicitis in Children and Adults? A Meta-Analysis. Radiology. 241(1):83-94, 2006 Oct. Meta-analysis Children: (26 studies, 9,356 patients); Adults (31 studies, 4,341 patients) To perform a meta-analysis to evaluate the diagnostic performance of US and CT for the diagnosis of appendicitis in pediatric and adult populations. Children: Sensitivity of 88% (95% CI: 86%, 90%) and specificity of 94% (95% CI: 92%, 95%), for US studies and sensitivity of 94% (95% CI: 92%, 97%) and specificity of 95% (95% CI: 94%, 97%) for CT studies. Adults: Pooled sensitivity and specificity for diagnosis were 83% (95% CI: 78%, 87%) and 93% (95% CI: 90%, 96%), respectively, for US studies and 94% (95% CI: 92%, 95%) and 94% (95% CI: 94%, 96%), respectively, for CT studies. CT had higher sensitivity and specificity than US. From a safety perspective, US should be considered initially in children. M
30. Kepner AM, Bacasnot JV, Stahlman BA. Intravenous contrast alone vs intravenous and oral contrast computed tomography for the diagnosis of appendicitis in adult ED patients. Am J Emerg Med. 30(9):1765-73, 2012 Nov. Experimental-Dx 114 IV patients and 113 IV and oral contrast patients To compare CT with IV contrast alone to CT with IV and oral contrast in adult patients with suspected appendicitis. Both IV (n=114) and IV and oral contrast (n=113) scans had 100% sensitivity (95% CI, 89.3-100 and 87.4-100, respectively) and NPV (95% CI, 93.7-100 and 93.9-100, respectively) for appendicitis. Specificity of IV and IV and oral contrast scans was 98.6% and 94.9% (95% CI, 91.6-99.9 and 86.9-98.4, respectively), respectively, with PPVs of 97.6% and 89.5% (95% CI, 85.9-99.9 and 74.2-96.6). Median times to emergency department disposition and operating room were 1 hour and 31 minutes (P<.0001) and 1 hour and 10 minutes (P=.089) faster for the IV group, respectively. Patients with negative IV scans were discharged nearly 2 hours faster (P=.001). 1
31. Laituri CA, Fraser JD, Aguayo P, et al. The lack of efficacy for oral contrast in the diagnosis of appendicitis by computed tomography. J Surg Res. 170(1):100-3, 2011 Sep. Observational-Dx 1561 patients To evaluate the impact of oral contrast on diagnostic efficiency and its impact on the patient. There were 1561 patients, of whom, 652 (41.8%) were diagnosed with appendicitis and 909 (58.2%) were not (non-appendicitis). Contrast was identified at least to the level of the terminal ileum in 72.4% of the entire population. The contrast was present in 76.2% of the non-appendicitis patients and 67.0% of the appendicitis patients (P = 0.01). Mean time from oral contrast administration to computed tomography (CT) imaging was 105.5 min, which was longer in patients with appendicitis (112.2 min) compared with non-appendicitis patients (100.9 min) (P = 0.01). Emesis of the contrast occurred in 19.3% of those with appendicitis and 12.9% of those without appendicitis (P = 0.001). Nasogastric tubes were placed in 5.8% of those with appendicitis and 5.1% of those without (P = 0.37). Appendicitis was confirmed at operation in 94.3% of those with contrast in the area and 94.4% of those without (P = 1.0). Pathology confirmed appendicitis in 90.6% of those with contrast in the area and 94.0% of those without (P = 0.17). 3
32. Latifi A, Labruto F, Kaiser S, Ullberg U, Sundin A, Torkzad MR. Does enteral contrast increase the accuracy of appendicitis diagnosis?. Radiol Technol. 82(4):294-9, 2011 Mar-Apr. Observational-Dx 246 CT examinations To evaluate retrospectively the accuracy of multidetector row computed tomography (MDCT) demonstration of appendicitis using enteral contrast agents. Of patients studied, 14.6% received no enteral contrast agent, 8.5% received both oral contrast and rectal contrast (enema), 46.7% received oral contrast and 30.1% received rectal contrast enemas. The accuracies for the computed tomography (CT) diagnosis of appendicitis with different combinations of agents ranged from 95% to 100%, with no significant difference among groups. 3
33. Kharbanda AB, Taylor GA, Bachur RG. Suspected appendicitis in children: rectal and intravenous contrast-enhanced versus intravenous contrast-enhanced CT. Radiology. 243(2):520-6, 2007 May. Observational-Dx 416 patients To retrospectively compare the diagnostic performance of IV contrast material-enhanced CT with that of IV and rectal contrast-enhanced CT in the evaluation of children suspected of having appendicitis. IV and rectal contrast-enhanced CT had a sensitivity of 92%, a specificity of 87% a NPV of 94%, and an accuracy of 89%. IV contrast-enhanced CT had a sensitivity of 93%, a specificity of 92%, a NPV of 95%, and an accuracy of 92%. There was no significant difference between the performance of IV contrast-enhanced CT and that of rectal and IV contrast-enhanced CT in children suspected of having appendicitis. 3
34. Callahan MJ, Anandalwar SP, MacDougall RD, et al. Pediatric CT dose reduction for suspected appendicitis: a practice quality improvement project using artificial gaussian noise--part 2, clinical outcomes. AJR Am J Roentgenol. 204(3):636-44, 2015 Mar. Observational-Dx 494 patients To determine the effect of a nominal 50% reduction in median absorbed radiation dose on sensitivity, specificity, and negative appendectomy rate of computed tomography (CT) for acute appendicitis in children. The nominal 50% dose reduction resulted in an actual 39% decrease in median absorbed radiation dose. Sensitivity of CT for diagnosis of acute appendicitis was 98% (95% confidence interval (CI), 91-100%) versus 97% (91-100%), and specificity was 93% (88-96%) versus 94% (90-97%) before and after dose reduction, respectively. The negative appendectomy rate was 4.5% (0.8-10.25%) before dose reduction and 4.0% (0.4-7.6%) after dose reduction. 3
35. Swanick CW, Gaca AM, Hollingsworth CL, et al. Comparison of conventional and simulated reduced-tube current MDCT for evaluation of suspected appendicitis in the pediatric population. AJR Am J Roentgenol. 201(3):651-8, 2013 Sep. Observational-Dx 21 boys; 39 girls To compare computed tomography (CT) with conventional and simulated reduced-tube current in the evaluation for acute appendicitis in children. For conventional examinations, the total number of reviews (60 casesx3 readers=180) in which the normal appendix was identified was 120 of 180 (66.7%), compared with 108 of 180 (60%) in the 50% (p=0.19) and 91 of 180 (50.6%) in the 75% (p=0.002) tube current-reduction groups. Appendicitis was identified in a total of 39 of 180 (21.7%), 38 of 180 (21.1%), and 37 of 180 (20.6%) examinations, respectively (p>0.05). This translates to sensitivities of 97% and 95% for the 50% and 75% tube current-reduction groups, respectively. Alternate diagnoses were detected in 14%, 16%, and 13% of scans, respectively. Compared with conventional-tube current examinations, reader confidence and assessment of image quality were significantly decreased for both tube current-reduction groups. 2
36. Akhtar W, Ali S, Arshad M, Ali FN, Nadeem N. Focused abdominal CT scan for acute appendicitis in children: can it help in need?. JPMA J Pak Med Assoc. 61(5):474-6, 2011 May. Observational-Dx 71 paediatric patients To evaluate the focused abdominal computed tomography (CT) scan [FACT] in clinically equivocal cases of acute appendicitis in paediatric population. The sensitivity of focused CT for acute appendicitis was 91%; specificity was 69% and accuracy of 76% while positive predictive value (PPV) and negative predictive value (NPV) were 58%, 94% respectively. 3
37. O&#39;Malley ME, Alharbi F, Chawla TP, Moshonov H. CT following US for possible appendicitis: anatomic coverage. Eur Radiol. 26(2):532-8, 2016 Feb. Observational-Dx 99 patients To determine superior-inferior anatomic borders for computed tomography (CT) following inconclusive/nondiagnostic ultrasound (US) for possible appendicitis. The study group included 83 women and 16 men; mean age 32 (median, 29; range 18-73) years. Final diagnoses were: nonspecific abdominal pain 50/99 (51%), appendicitis 26/99 (26%), gynaecological 12/99 (12%), gastrointestinal 9/99 (10%), and musculoskeletal 2/99 (2%). Median dose-length product for standard CT was 890.0 (range, 306.3 - 2493.9) To confidently diagnose/exclude appendicitis or identify alternative diagnoses, maximum superior-inferior anatomic CT coverage was the superior border of L2-superior border of pubic symphysis, for both reviewers. Targeted CT would reduce anatomic coverage by 30-55% (mean 39%, median 40%) compared to standard CT. 2
38. Hoecker CC, Billman GF. The utility of unenhanced computed tomography in appendicitis in children. Journal of Emergency Medicine. 28(4):415-21, 2005 May.J Emerg Med. 28(4):415-21, 2005 May. Observational-Dx 112 patients To evaluate the utility of unenhanced helical computed tomography (UHCT) in appendicitis in children The performance characteristics of UHCT were as follows: sensitivity 87.5% (95% CI: 75.8–94.8%), specificity 93.7% (95% CI: 85.4%–98.0%), positive predictive value 91.3% (95% CI: 83.2%–99.4%), negative predictive value 90.8% (95% CI: 83.7%–97.8%), overall diagnostic accuracy 90.9% (95% CI: 85.7–96.3%). Positive and negative likelihood ratios were 13.8 (95% CI: 5.3–35.8) and 0.13 (95% CI: 0.06–0.28), respectively. 2
39. Ozturkmen Akay H, Akpinar E, Akgul Ozmen C, Ergun O, Haliloglu M. Visualization of the normal appendix in children by non-contrast MDCT. Acta Chir Belg. 107(5):531-4, 2007 Sep-Oct. Observational-Dx 105 patients To investigate the identification of normal appendix by non-contrast multi-detector CT (MDCT) The appendix was clearly distinguished in 72 patients (68.5%). The difference in appendix visualization ratesbetween patients with low and medium amounts of abdominal fat was statistically significant (p < 0.001). Visualizationincreased with age. The greatest external diameter was between 2.8 and 10 mm, with a mean of 5 ± 1.34 mm. 3
40. Dillman JR, Gadepalli S, Sroufe NS, et al. Equivocal Pediatric Appendicitis: Unenhanced MR Imaging Protocol for Nonsedated Children-A Clinical Effectiveness Study. Radiology. 279(1):216-25, 2016 Apr. Observational-Dx 103 MR images; 58 CT images To determine retrospectively the clinical effectiveness of an unenhanced magnetic resonance (MR) imaging protocol for evaluation of equivocal appendicitis in children. Diagnostic performance with MR imaging was comparable to that with computed tomography (CT) for equivocal pediatric appendicitis. For MR imaging (n = 103), sensitivity was 94.4% (95% confidence interval (CI): 72.7%, 99.9%) and specificity was 100% (95% CI: 95.8%, 100%); for CT [n = 58], sensitivity was 100% (95% CI: 71.5%, 100%), specificity was 97.9% (95% CI: 88.7%, 100%). Diagnostic performance with MR imaging and CT also was comparable for detection of appendiceal perforation, with MR imaging (n = 103) sensitivity of 90.0% (95% CI: 55.5%, 99.8%) and specificity of 85.7% (95% CI: 42.1%, 99.6%) and CT (n = 58) sensitivity of 75.0% (95% CI: 19.4%, 99.4%) and specificity of 85.7% (95% CI: 42.1%, 99.6%). The proportion of examinations with identifiable alternative diagnoses was similar at MR imaging to that at CT (19 of 103 [18.4%] vs eight of 58 [13.8%], respectively; P = .52). The proportion of appendixes seen at MR imaging and at CT also was similar (77 of 103 [74.8%] vs 50 of 58 [86.2%], respectively; P = .11). 3
41. Duke E, Kalb B, Arif-Tiwari H, et al. A Systematic Review and Meta-Analysis of Diagnostic Performance of MRI for Evaluation of Acute Appendicitis. [Review]. AJR Am J Roentgenol. 206(3):508-17, 2016 Mar. Meta-analysis 30 studies To determine the accuracy of magnetic resonance imaging (MRI) in the diagnosis of acute appendicitis in the general population and in subsets of pregnant patients and children. A total of 30 studies that comprised 2665 patients were reviewed. The sensitivity and specificity of MRI for the diagnosis of acute appendicitis are 96% (95% CI, 95-97%) and 96% (95% CI, 95-97%), respectively. In a subgroup of studies that focused solely on pregnant patients, the sensitivity and specificity of MRI were 94% (95% CI, 87-98%) and 97% (95% CI, 96-98%), respectively, whereas in studies that focused on children, sensitivity and specificity were found to be 96% (95% CI, 95-97%) and 96% (95% CI, 94-98%), respectively. Good
42. Johnson AK, Filippi CG, Andrews T, et al. Ultrafast 3-T MRI in the evaluation of children with acute lower abdominal pain for the detection of appendicitis. AJR Am J Roentgenol. 198(6):1424-30, 2012 Jun. Observational-Dx 42 patients To evaluate the feasibility of ultrafast 3-T MRI in the evaluation of children with acute lower abdominal pain for the detection of appendicitis. 12/42 cases of acute appendicitis were detected with 100% sensitivity, 99% specificity, 100% NPV value, and 98% PPV, all of which were statistically significant (P<0.01). The pooled and individual receiver operating characteristic curves for radiologists' interpretation of the diagnosis of acute appendicitis were >0.95 in all cases (P<0.01). 1
43. Kulaylat AN, Moore MM, Engbrecht BW, et al. An implemented MRI program to eliminate radiation from the evaluation of pediatric appendicitis. J Pediatr Surg. 50(8):1359-63, 2015 Aug. Observational-Dx 510 patients To establish the diagnostic parameters of an implemented Magnetic resonance imaging (MRI) program in a large cohort of patients in the evaluation of suspected appendicitis over an extended study interval and to evaluate the clinical outcomes associated with the use of a single-stage MRI program in this setting. MRI diagnostic characteristics were: sensitivity 96.8% (95% CI: 92.1%-99.1%), specificity 97.4% (95% CI: 95.3-98.7), positive predictive value 92.4% (95% CI: 86.5-96.3), and negative predictive value 98.9% (95% CI: 97.3%-99.7%). Radiologic time parameters included: median time from request to scan, 71 minutes (IQR: 51-102), imaging duration, 11 minutes (interquantile range (IQR): 8-17), and request to interpretation, 2.0 hours (IQR: 1.6-2.6). Clinical time parameters included: median time from initial assessment to admit order, 4.1 hours (IQR: 3.1-5.1), assessment to antibiotic administration 4.7 hours (IQR: 3.9-6.7), and assessment to operating room 9.1 hours (IQR: 5.8-12.7). Median length of stay was 1.2 days (range: 0.2-19.5). 3
44. Moore MM, Gustas CN, Choudhary AK, et al. MRI for clinically suspected pediatric appendicitis: an implemented program. Pediatr Radiol. 42(9):1056-63, 2012 Sep. Observational-Dx 208 children To describe the institution's development and the results of a fully implemented clinical program using MRI as the primary imaging evaluation for children with suspected appendicitis. Diagnostic accuracy of MRI for pediatric appendicitis indicated a sensitivity of 97.6% (CI: 87.1%-99.9%), specificity 97.0% (CI: 93.2%-99.0%), PPV 88.9% (CI: 76.0%-96.3%), and NPV 99.4% (CI: 96.6%-99.9%). Time parameter analysis indicated clinical feasibility, with time requested to first sequence obtained mean of 78.7 +/- 52.5 min, median 65 min; first-to-last sequence time stamp mean 14.2 +/- 8.8 min, median 12 min; last sequence to report mean 57.4 +/- 35.2 min, median 46 min. Mean age was 11.2 +/- 3.6 years old. Girls represented 57% of patients. 3
45. Orth RC, Guillerman RP, Zhang W, Masand P, Bisset GS 3rd. Prospective comparison of MR imaging and US for the diagnosis of pediatric appendicitis.[Erratum appears in Radiology. 2015 Dec;277(3):927; PMID: 26599937]. Radiology. 272(1):233-40, 2014 Jul. Observational-Dx 453 patients To prospectively compare nonenhanced magnetic resonance (MR) imaging and ultrasonography (US) for the diagnosis of pediatric appendicitis. Thirty (37%) patients had pathologically proved acute appendicitis. When equivocal interpretations were designated positive, sensitivity was 93.3% for MR imaging (95% confidence interval [CI]: 77.9%, 99.2%) and 90.0% for US (95% CI: 73.5%, 97.9%), P > .99; specificity was 98% for MR imaging (95% CI: 89.6%, 100%) and 86.3% for US (95% CI:73.7%, 94.3%), P = .03; PPV was 96.5% for MR imaging (95% CI: 82.2%, 99.9%) and 79.4% for US (95% CI: 62.1%, 91.3%), P = .007; and NPV was 96.2% for MR imaging (95% CI: 86.8%, 99.5%) and 93.6% for US (95% CI: 82.4%, 98.7%), P = .45, with substantial intertechnique (kappa = 0.77; 95% CI: 0.63, 0.90) and interobserver (kappa = 0.76; 95% CI: 0.61, 0.91) agreement. When equivocal interpretations were designated negative, MR imaging sensitivity, specificity, PPV, and NPV were unchanged. For US, sensitivity was 86.7% (95% CI: 69.3%, 96.2%), P = .5; specificity was 100% (95% CI: 93.0%, 100%), P > .99; PPV was 100% (95% CI: 86.8%, 100%), P = .31; and NPV was 92.7% (95% CI: 82.4%, 98.0%), P = .16, with almost perfect intertechnique (kappa = 0.92; 95% CI: 0.83, 1.00) and substantial interobserver (kappa = 0.72; 95% CI: 0.58, 0.87) agreement. 2
46. Kinner S, Pickhardt PJ, Riedesel EL, et al. Diagnostic Accuracy of MRI Versus CT for the Evaluation of Acute Appendicitis in Children and Young Adults. AJR Am J Roentgenol. 209(4):911-919, 2017 Oct. Observational-Dx 48 patients To compare the diagnostic accuracy of contrast-enhanced MRI with that of contrast-enhanced CT for the diagnosis of appendicitis in adolescents when interpreted by abdominal radiologists and pediatric radiologists. Sensitivity and specificity were 85.9% (95% CI, 76.2-92.7%) and 93.8% (95% CI, 89.7-96.7%) for unenhanced MRI, 93.6% (95% CI, 85.6-97.9%) and 94.3% (95% CI, 90.2-97%) for contrast-enhanced MRI, and 93.6% (95% CI, 85.6-97.9%) and 94.3% (95% CI, 90.2-97%) for CT. No difference was found in the diagnostic accuracy or interpretation time when comparing abdominal radiologists to pediatric radiologists (CT, 3.0 min vs 2.8 min; contrast-enhanced MRI, 2.4 min vs 1.8 min; unenhanced MRI, 1.5 min vs 2.3 min). Substantial agreement between abdominal and pediatric radiologists was seen for all methods (kappa = 0.72-0.83). 1
47. Bayraktutan U, Oral A, Kantarci M, et al. Diagnostic performance of diffusion-weighted MR imaging in detecting acute appendicitis in children: comparison with conventional MRI and surgical findings. J Magn Reson Imaging. 39(6):1518-24, 2014 Jun. Observational-Dx 45 patients To determine the value of diffusion-weighted Magnetic Resonance Imaging (DWI-MRI) for the diagnosis of acute appendicitis in children. A combination of DWI and conventional MRI was the most sensitive and the most accurate, with corresponding sensitivity and accuracy of 0.92 and 0.92, respectively. Using DWI alone the sensitivity and accuracy was found to be 0.78 and 0.77, respectively. Using conventional MRI alone, sensitivity of 0.81 and accuracy of 0.82 was found for the consensus of the two observers. 2
48. Epifanio M, Antonio de Medeiros Lima M, Correa P, Baldisserotto M. An Imaging Diagnostic Protocol in Children with Clinically Suspected Acute Appendicitis. Am Surg. 82(5):390-6, 2016 May. Observational-Dx 166 children To evaluate a new diagnostic strategy using clinical findings followed by ultrasound (US) and, in selected cases, magnetic resonance imaging (MRI). Of the 166 patients, 78 (47%) had acute appendicitis and 88 (53%) had other diseases. The strategy under study had a sensitivity of 96 per cent, specificity of 100 per cent, positive predictive value of 100 per cent, negative predictive value of 97 per cent, and accuracy of 98 per cent. Eight patients remained undiagnosed and underwent MRI. After MRI two girls presented normal appendixes and were discharged. One girl had an enlarged appendix on MRI and appendicitis could have been confirmed by surgery. In the other five patients, no other sign of the disease was detected by MRI such as an inflammatory mass, free fluid or an abscess in the right iliac fossa. All of them were discharged after clinical observation. In the vast majority of cases the correct diagnosis was reached by clinical and US examinations. 2
49. Gregory S, Kuntz K, Sainfort F, Kharbanda A. Cost-Effectiveness of Integrating a Clinical Decision Rule and Staged Imaging Protocol for Diagnosis of Appendicitis. Value Health. 19(1):28-35, 2016 Jan. Review/Other-Dx N/A To evaluate the cost-effectiveness of a diagnostic protocol for appendicitis in children, the use of a validated clinical decision rule (CDR) and a staged imaging protocol, compared with usual care. The integrated strategy, the CDR followed by staged imaging, was found to be the most cost-effective approach. Cost savings accrued from the reduction in computed tomography (CT) utilization for low-risk patients compared with the other two strategies. The addition of ultrasound (US) to the CDR strategy reduced CT utilization by an additional 10.9%, its main cost advantage, with negligible change in  net health benefits from false-negative US results, and associated morbidity or mortality. 4
50. Kim DY, Shim DH, Cho KY. Use of the Pediatric Appendicitis Score in a Community Hospital. Indian Pediatr. 53(3):217-20, 2016 Mar. Observational-Dx 285 patients To suggest the use of the Pediatric appendicitis score (PAS) for diagnosing acute pediatric appendicitis in a community hospital. The appendicitis group had a significantly higher PAS and more frequently positive computed tomography (CT) findings for appendicitis than the non-appendicitis group (P<0.01). There were no significant differences in the diagnostic performance of the PAS and CT. Patients with a PAS of 1 to 3 could be discharged without further imaging study, those with a PAS of 4 to 6 might need to undergo further imaging study, and those with 7 to 10 PAS required surgical consultation with imaging study. 3
51. Ulukaya Durakbasa C, Tasbasi I, Tosyali AN, Mutus M, Sehiralti V, Zemheri E. An evaluation of individual plain abdominal radiography findings in pediatric appendicitis: results from a series of 424 children. Ulus Travma Acil Cerrahi Derg. 12(1):51-8, 2006 Jan. Observational-Dx 424 children To collect the results of the plain abdominal radiography (PAR) signs, to determine their individual diagnostic values, and to discuss them under a brief literature review. Appendicitis was confirmed in 378 (89%) patients. Among the remaining 46 (11%) patients with a normal appendix, 20 (5%) had other intraabdominal pathologies. Calcified fecalith, mass image in right-lower-quadrant (RLQ), psoas obscuration, and localized extraluminal air signs were all highly specific and therefore, unlikely to be present if the appendix is normal. On the other hand, the sensitivity values were low, in general, for all the PAR signs investigated. Yet, presence of dilated transverse colon and/or single air fluid level in the RLQ has the highest percentage occurrence with appendicitis. 3
52. Tayal VS, Bullard M, Swanson DR, et al. ED endovaginal pelvic ultrasound in nonpregnant women with right lower quadrant pain. Am J Emerg Med. 26(1):81-5, 2008 Jan. Observational-Dx 40 patients To show that sonographic skills with first-trimester pelvic ultrasound could be used to address the issue of contributory pelvic pathology. With a positive emergency department (ED) endovaginal ultrasound (EVUS), mean physician probability increased for gynecologic (24%) and decreased for both surgical (14%) and medical (20%) disease. With a negative ED EVUS, mean physician probability increased for surgical disease (5.3%) and decreased for gynecologic disease (18.6%). 3
53. McKay R, Shepherd J. The use of the clinical scoring system by Alvarado in the decision to perform computed tomography for acute appendicitis in the ED. Am J Emerg Med. 25(5):489-93, 2007 Jun. Observational-Dx 96 patients To develop guidelines for Computed tomography (CT) scanning based on Alvarado clinical scores for patients with suspected and confirmed cases of appendicitis. Computed tomography scans with Alvarado scores of 3 or lower were performed in 37% (55/150) of patients to rule out appendicitis. The sensitivity of Alvarado scores 3 or lower for not having appendicitis was 96.2% (53/55), and the specificity 67% (2/3). Patients with Alvarado scores 7 or higher had an incidence of acute appendicitis of 77.7% (28/36). The sensitivity of Alvarado scores 7 or higher for appendicitis was 77% (28/36), and the specificity 100% (8/8). The sensitivity of equivocal Alvarado scores, defined as scores of 4 to 6, for acute appendicitis was 35.6% (21/59), and the specificity 94% (36/38). The sensitivity and specificity of CT scans in patients with equivocal Alvarado scores remained high, at 90.4% and 95%, respectively. 3
54. Halverson M, Delgado J, Mahboubi S. Extra-appendiceal findings in pediatric abdominal CT for suspected appendicitis. Pediatr Radiol. 44(7):816-20, 2014 Jul. Observational-Dx 165 children To determine the prevalence and characteristics of extra-appendiceal and incidental findings in pediatric abdominal computed tomography (CT) performed for suspected appendicitis One hundred sixty-five children had abdominal CT for suspected appendicitis. Seventy-seven extra-appendiceal findings were found in 57 (34.5%) patients. Most findings (64 of 77) were discovered in children who did not have appendicitis. Forty-one of these findings (53%) could potentially help explain the patient's symptoms, while 30 of the findings (39%) were abnormalities that were unlikely to be related to the symptoms but required clinical correlation and sometimes further work-up. Six of the findings (8%) had doubtful or no clinical significance. 3
55. Koning JL, Naheedy JH, Kruk PG. Diagnostic performance of contrast-enhanced MR for acute appendicitis and alternative causes of abdominal pain in children. Pediatr Radiol. 44(8):948-55, 2014 Aug. Observational-Dx 364 pediatric patients To examine the diagnostic performance of contrast-enhanced magnetic resonance imaging (MRI) for acute appendicitis and alternative entities in the pediatric population presenting with acute abdominal pain. There were 132 cases of pathologically confirmed appendicitis out of 364 pediatric patients (36.3%) included in the study. Overall sensitivity and specificity were 96.2% (95% confidence interval (CI) [91.4-98.4%]) and 95.7% (95% CI [92.3-97.6%]), respectively. Positive predictive value and negative predictive value were 92.7% (95% CI [86.6-96.3%]) and 97.8% (95% CI [94.7-99.1%]), respectively. The appendix was visualized in 243 cases (66.8%). Imaging confirmed alternative diagnoses in 75 patients, including most commonly colitis, enteritis or terminal ileitis (n = 25, 6.9%), adnexal cysts (n = 25, 6.9%) and mesenteric adenitis (n = 7, 1.9%). 3
56. Pogorelic Z, Rak S, Mrklic I, Juric I. Prospective validation of Alvarado score and Pediatric Appendicitis Score for the diagnosis of acute appendicitis in children. Pediatr Emerg Care. 31(3):164-8, 2015 Mar. Observational-Dx 311 patients To compare the results of the Alvarado and Pediatric Appendicitis Score (PAS) scoring systems and to establish which one is more reliable in setting the diagnosis of acute appendicitis in children. A total of 311 patients were included in the study, and 265 (85.2%) of them had acute appendicitis. Mean Alvarado score for patients with appendicitis was 8.2 and 6.7 for those without (P < 0.001). Mean PAS for patients with appendicitis was of 7.8 and 6.6 for those without (P < 0.001). Based on the ROC curve analysis, a cutoff value for both scoring systems was 7. In patients with acute appendicitis and Alvarado score of 7 or higher, the correct diagnosis would have been set in 236 patients (sensitivity, 89%; specificity, 59%; positive predictive value, 93.1%), whereas in patients with acute appendicitis and a PAS of 7 or higher, the correct diagnosis would have been set in 228 patients (sensitivity, 86%; specificity, 50%; positive predictive value, 90.1%). No significant difference was found in sensitivity and specificity between the observed scoring systems. 3
57. Toprak H, Kilincaslan H, Ahmad IC, et al. Integration of ultrasound findings with Alvarado score in children with suspected appendicitis. Pediatr Int. 56(1):95-9, 2014 Feb. Observational-Dx 122 children To investigate the integration of ultrasound (US) findings with Alvarado score in diagnosing or excluding acute appendicitis. Alvarado score was a good predictor of appendicitis for scores >/=7. 3
58. Bachur RG, Callahan MJ, Monuteaux MC, Rangel SJ. Integration of ultrasound findings and a clinical score in the diagnostic evaluation of pediatric appendicitis. J Pediatr. 166(5):1134-9, 2015 May. Review/Other-Dx 52,290 patients To examine the use of computed tomography (CT) and ultrasound for age and gender subgroups of children undergoing an appendectomy; and to study the association between imaging and negative appendectomy rates (NARs) among these subgroups. A total of 8 959 155 visits at 40 pediatric emergency departments were investigated; 55 227 children had appendicitis. The NAR was 3.6%. NARs were highest for children younger than 5 years (boys 16.8%, girls 14.6%) and girls older than 10 years (4.8%). At the institutional level, increased rates of diagnostic imaging (ultrasound and/or CT) were associated with lower NARs for all age and gender subgroups other than children younger than 5 years, The NAR was 1.2% for boys older than 5 years without any diagnostic imaging. 4
59. Fallon SC, Orth RC, Guillerman RP, et al. Development and validation of an ultrasound scoring system for children with suspected acute appendicitis. Pediatr Radiol. 45(13):1945-52, 2015 Dec. Observational-Dx 1921 US exams To evaluate implementation of this scoring system and its ability to risk-stratify children with suspected appendicitis. We identified 1,235 patients in the pre-implementation and 686 patients in the post-implementation groups. Appy- Score use increased from 24% (37/155) in July to 89% (226/ 254) in September (P<0.001). Appendicitis frequency by Appy-Score stratum post-implementation was: 1=0.5%, 2= 0%, 3=9.5%, 4=44%, 5a=92.3%, and 5b=100%. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 96.3% (287/298), 93.9% (880/937), 83.4% (287/344), and 98.8% (880/891) pre-implementation and 93.0% (200/215), 92.6% (436/471), 85.1% (200/235), and 96.7% (436/451) post-implementation – only NPV was statistically different (P=0.012). Computed Tomography (CT) imaging after ultrasound (US) decreased by 31% between pre- and post-implementation, 8.6% (106/1235) vs. 6.0% (41/686); P=0.048). Negative appendectomy rates did not change (4.4% vs. 4.1%, P=0.8). 2
60. Nielsen JW, Boomer L, Kurtovic K, et al. Reducing computed tomography scans for appendicitis by introduction of a standardized and validated ultrasonography report template. J Pediatr Surg. 50(1):144-8, 2015 Jan. Observational-Dx 304 Pre-templates; 2033 Post-templates. To reduce the diagnostic use of computed tomography (CT) scans, we implemented a standardized ultrasound report template based on validated secondary signs of appendicitis. In Period 178 of 304 (25.7%) patients had appendicitis versus 385 of 2033 (18.9%) in Period 2 (p=0.006). Non-diagnostic exams decreased from 48% to 0.1% (p<0.001). Ultrasound sensitivity improved from 66.67% to 92.2% (p<0.001). Specificity did not significantly change (96.9% to 97.69%, p=0.46). CT utilization for appendicitis decreased from 44.3% in Period 1 to 14.5% at the end of Period 2 (p<0.001). 3
61. Ramarajan N, Krishnamoorthi R, Barth R, et al. An interdisciplinary initiative to reduce radiation exposure: evaluation of appendicitis in a pediatric emergency department with clinical assessment supported by a staged ultrasound and computed tomography pathway. Acad Emerg Med. 16(11):1258-65, 2009 Nov. Observational-Dx 680 patients To describe an interdisciplinary initiative to use a staged ultrasound (US) and computed tomography (CT) pathway to maximize diagnostic accuracy while minimizing radiation exposure. A total of 680 patients met the study criteria. A total of 407 patients (60%) followed the pathway. Two-hundred of these (49%) were managed definitively without CT. A total of 106 patients (26%) had a positive US for appendicitis; 94 (23%) had a negative US. A total of 207 patients had equivocal US with follow-up CT. A total of 144 patients went to the operating room (OR); 10 patients (7%) had negative appendectomies. One case of appendicitis was missed (<0.5%). The sensitivity, specificity, negative predictive value, and positive predictive values of our staged US-CT pathway were 99%, 91%, 99%, and 85%, respectively. A total of 228 of 680 patients (34%) had an equivocal US with no follow-up CT. Of these patients, 10 (4%) went to the OR with one negative appendectomy. A total of 218 patients (32%) were observed clinically without complications. 2
62. Garcia K, Hernanz-Schulman M, Bennett DL, Morrow SE, Yu C, Kan JH. Suspected appendicitis in children: diagnostic importance of normal abdominopelvic CT findings with nonvisualized appendix. Radiology. 250(2):531-7, 2009 Feb. Observational-Dx 1,139 children To determine whether lack of visualization of the appendix on otherwise normal abdominopelvic CT images can help exclude appendicitis in the pediatric population. NPV of a normal CT examination in patients with a nonvisualized appendix was 98.7% (95% CI: 95.5%, 99.8%); that with a visualized appendix, 99.8% (95% CI: 98.7%, 99.99%); that with a partially visualized appendix, 100% (95% CI: 97.8%, 100%); and that with a fully visualized appendix, 99.6% (95% CI: 97.8%, 99.99%). 3
63. Stewart JK, Olcott EW, Jeffrey RB. Sonography for appendicitis: nonvisualization of the appendix is an indication for active clinical observation rather than direct referral for computed tomography. J Clin Ultrasound. 40(8):455-61, 2012 Oct. Observational-Dx 260 patients To determine the prevalence of perforated and nonperforated appendicitis in patients with nonvisualization of the appendix on ultrasound (US) performed for suspected appendicitis, and to evaluate the value of computed tomography (CT) in these patients. Of the 400 patients, 140 (35%) had either a normal (80 patients, 25%) or an abnormal appendix (60 patients, 15%); 260 (65%) had nonvisualization of the appendix. Overall 75 patients had appendicitis (18.8%) and 17 (4.3%) had appendicitis with perforation. Of the 260 patients with nonvisualization of the appendix, 14 patients (5.4%) had appendicitis and 2 were perforated (0.8%). The prevalence of perforated and nonperforated appendicitis in this group was significantly lower than the overall group (p < 0.001 and p < 0.01, respectively). Of these 260 patients, 101 patients (38.8%) had CT within 48 hours and 79 (78.2%) had normal scans. 4
64. Wiersma F, Toorenvliet BR, Bloem JL, Allema JH, Holscher HC. US examination of the appendix in children with suspected appendicitis: the additional value of secondary signs. Eur Radiol. 19(2):455-61, 2009 Feb. Observational-Dx 212 patients To evaluate the additional value of secondary signs in the diagnosing of appendicitis in children with ultrasound. Prevalence of appendicitis was 71/212 (34%). Negative predictive values of groups 1 and 2 were 99% and 100%, respectively. Positive predictive values of groups 3 and 4 were 85% and 95%, respectively. In groups 3 and 4, hyperechoic mesenteric fat was seen in 73/75 (97.3%), fluid collections and dilated bowel loops were seen in 12/75 (16.0%) and 5/75 (6.6%), respectively. 3
65. Srinivasan A, Servaes S, Pena A, Darge K. Utility of CT after sonography for suspected appendicitis in children: integration of a clinical scoring system with a staged imaging protocol. EMERG. RADIOL.. 22(1):31-42, 2015 Feb. Observational-Dx 218 patients To improve diagnosis of pediatric appendicitis, many institutions have implemented a staged imaging protocol utilizing ultrasonography (US) first and then computed tomography (CT). Studies of 211 children (mean age 11.3 years) were included. The positive threshold for appendicitis score (AS) was determined to be 6 out of 10. When appendicitis score (AS) and US were concordant (N = 140), the sensitivity and specificity of US were similar to CT. When AS and US were discordant (N = 71) and also when AS >/= 6 (N = 84), subsequent CT showed superior sensitivity and specificity to US alone. In the subset where US showed neither the appendix nor inflammatory change in the right lower quadrant (126/211, 60 % of scans), when AS < 6 (N = 83), the negative predictive value (NPV) of US was 0.98. However, when AS >/= 6 (N = 43), NPV of US was 0.58, and the positive predictive value of subsequent CT was 1. There was a significant decrease in depiction of the appendix on US with patient weight-to-age ratio of >6 (kg/year, P < 0.001) and after-hours (1700 -0730 hours) performance of US (P < 0.001). Results suggest that the appendicitis score has utility in guiding an imaging protocol and support the contention that non-visualization of the appendix on US is not intrinsically non-diagnostic. There was little benefit to additional CT when AS < 6 and US did not show the appendix or evidence of inflammation; this would have avoided CT in 140/211 (66 %) patients. 3
66. Ramarajan N, Krishnamoorthi R, Gharahbaghian L, Pirrotta E, Barth RA, Wang NE. Clinical correlation needed: what do emergency physicians do after an equivocal ultrasound for pediatric acute appendicitis?. J Clin Ultrasound. 42(7):385-94, 2014 Sep. Observational-Dx 620 patients To assess prevalence of acute appendicitis and outcomes in patients with equivocal ultrasound (US) with and without follow-up computed tomography (CT) and to identify variables associated with ordering a follow-up CT. Fifty-five percent (340/620) of children with equivocal US did not receive CT, none of whom returned with a missed appendicitis. The prevalence of appendicitis in children with equivocal US was 12.5% (78/620). In children with follow-up CT, the prevalence was 22.1% (62/280); in those without follow-up CT, the prevalence was 4.7% (16/340). Recursive partitioning identified age >11 years, leukocytosis >15,000 cells/ml, and secondary signs predisposing toward acute appendicitis on US as significant predictors of CT. 3
67. Schuh S, Chan K, Langer JC, et al. Properties of serial ultrasound clinical diagnostic pathway in suspected appendicitis and related computed tomography use. Acad Emerg Med. 22(4):406-14, 2015 Apr. Observational-Dx 294 children To determine the diagnostic accuracy of a serial ultrasound (US) clinical diagnostic pathway to detect appendicitis in children presenting to the emergency department (ED). The secondary objective was to examine the diagnostic performance of the initial and interval US and to compare the accuracy of the pathway to that of the initial US. Of the 294 study children, 111 (38%) had appendicitis. Using the serial US clinical diagnostic pathway, 274 of 294 children (93%, 95% confidence interval [CI] = 90% to 96%) had diagnostically accurate results: 108 of the 111 (97%) appendicitis cases were successfully identified by the pathway without CT scans (two missed and one CT), and 166 of the 183 (91%) negative cases were ruled out without CT scans (14 negative operations and three CTs). The sensitivity of this pathway was 108 of 111 (97%, 95% CI = 94% to 100%), specificity 166 of 183 (91%, 95% CI = 87% to 95%), positive predictive value 108 of 125 (86%; 95% CI = 79% to 92%), and negative predictive value 166 of 169 (98%, 95% CI = 96% to 100%). The diagnostic accuracy of the pathway was higher than that of the initial US alone (274 of 294 vs. 160 of 294; p < 0.0001). Of 123 patients with equivocal initial US, concern about appendicitis subsided on clinical reassessment in 73 (no surgery and no missed appendicitis). Of 50 children with persistent symptoms, 40 underwent interval US and 10 had surgical consultation alone. The interval US confirmed or ruled out appendicitis in 22 of 40 children (55.0%) with equivocal initial US, with one false-positive interval US. 2
68. Atema JJ, Gans SL, Van Randen A, et al. Comparison of Imaging Strategies with Conditional versus Immediate Contrast-Enhanced Computed Tomography in Patients with Clinical Suspicion of Acute Appendicitis. Eur Radiol. 25(8):2445-52, 2015 Aug. Observational-Dx 422 patients To compare the diagnostic accuracy of conditional computed tomography (CT), i.e. CT when initial ultrasound findings are negative or inconclusive, and immediate CT for patients with suspected appendicitis. A total of 422 patients were included with final diagnosis appendicitis in 251 (60 %). For 199 patients (47 %), ultrasound findings were inconclusive or negative. Conditional CT imaging correctly identified 241 of 251 (96 %) appendicitis cases (95 %CI, 92 % to 98 %), versus 238 (95 %) with immediate CT (95 %CI, 91 % to 97 %). The specificity of conditional CT imaging was lower: 77 % (95 %CI, 70 % to 83 %) versus 87 % for immediate CT (95 %CI, 81 % to 91 %). 2
69. Thirumoorthi AS, Fefferman NR, Ginsburg HB, Kuenzler KA, Tomita SS. Managing radiation exposure in children--reexamining the role of ultrasound in the diagnosis of appendicitis. J Pediatr Surg. 47(12):2268-72, 2012 Dec. Observational-Dx 802 patients To assess the efficacy and accuracy of ultrasonography (US) and selective computed tomography (CT) in the diagnosis of acute appendicitis in children. Of the 601 pediatric appendectomies performed, a total of 275 (46%) were diagnosed by protocol. The selective protocol had a sensitivity of 94.2%, specificity of 97.5%, positive predictive value of 95.2%, and negative predictive value of 97.0%. The negative appendectomy rate was 1.82%, and the missed appendicitis rate was 0%. No patient discharged after only ultrasound evaluation without undergoing surgery reported missed appendicitis on the survey (41.7% response rate). Protocol use increased from 6.7% to 88.3%. US was the sole imaging modality in 630 of all 802 patients (78.6%). 3
70. Krishnamoorthi R, Ramarajan N, Wang NE, et al. Effectiveness of a staged US and CT protocol for the diagnosis of pediatric appendicitis: reducing radiation exposure in the age of ALARA. Radiology. 259(1):231-9, 2011 Apr. Observational-Dx 631 patients To evaluate the effectiveness of a staged US and CT imaging protocol for the accurate diagnosis of suspected appendicitis in children and the opportunity for reducing the number of CT examinations and associated radiation exposure. The sensitivity and specificity of the staged protocol were 98.6% and 90.6%, respectively. The negative appendectomy rate was 8.1% (19/235 patients), and the missed appendicitis rate was less than 0.5% (1/631 patients). CT was avoided in 333/631 patients (53%) in whom the protocol was followed and in whom the US findings were definitive. 3
71. Herliczek TW, Swenson DW, Mayo-Smith WW. Utility of MRI after inconclusive ultrasound in pediatric patients with suspected appendicitis: retrospective review of 60 consecutive patients. AJR Am J Roentgenol. 200(5):969-73, 2013 May. Observational-Dx 60 patients To examine the utility of appendix magnetic resonance imaging (MRI) in evaluation of pediatric patients with right lower quadrant pain and inconclusive appendix sonography findings. Ten of 60 patients (17%) had acute appendicitis. Both readers graded the same 12 examinations as positive and the same 48 examinations as negative for acute appendicitis, with a kappa value of 1.00 (expected agreement, 0.695). No MRI examination was interpreted as indeterminate. The sensitivity and specificity of MRI for acute appendicitis in children with inconclusive appendix ultrasound findings were 100% (95% confidence interval (CI), 0.72-1.00) and 96% (95% CI, 0.87-0.98), respectively. The positive predictive value for the examination was 83%, the negative predictive value was 100%, and overall test accuracy was 97%. 2
72. Aspelund G, Fingeret A, Gross E, et al. Ultrasonography/MRI versus CT for diagnosing appendicitis. Pediatrics. 133(4):586-93, 2014 Apr. Observational-Dx 662 patients To compare Ultrasonography/ magnetic resonance imaging (MRI) versus computed tomography (CT) for diagnosing appendicitis. Six hundred sixty-two patients had imaging for suspected appendicitis (group A = 265; group B = 397, of which 136 [51%] and 161 [41%], respectively, had positive imaging for appendicitis). Negative appendectomy rate was 2.5% for group A and 1.4% for group B. Perforation rate was similar for both groups. Time from triage to antibiotic administration and operation did not differ between groups A and B. There was higher proportion of positive imaging and appendectomies in group A and thus more negative imaging tests in group B (ultrasonography and MRI), but diagnostic accuracy of the 2 imaging pathways was similar. 3
73. Serres SK, Cameron DB, Glass CC, et al. Time to Appendectomy and Risk of Complicated Appendicitis and Adverse Outcomes in Children. Jama, Pediatr.. 171(8):740-746, 2017 Aug 01. Observational-Dx 6767 patients To examine the association between time to appendectomy (TTA) and risk of complicated appendicitis and postoperative complications. Of the 6767 patients who met the inclusion criteria, 2429 were included in the analysis (median age, 10 years; interquartile range, 8-13 years; 1467 [60.4%] male). Median hospital TTA was 7.4 hours (range, 5.0-19.2 hours), and 574 patients (23.6%) were diagnosed with complicated appendicitis (range, 5.2%-51.1% across hospitals). In multivariable analyses, increasing TTA was not associated with risk of complicated appendicitis (odds ratio per 1-hour increase in TTA, 0.99; 95% CI, 0.97-1.02). The odds ratios of complicated appendicitis for late vs early TTA across hospitals ranged from 0.39 to 9.63, and only 1 of the 23 hospitals had a statistically significant increase in their late TTA group (odds ratio, 9.63; 95% CI, 1.08-86.17; P = .03). Increasing TTA was associated with longer LOS (increase in mean LOS for each additional hour of TTA, 0.06 days; 95% CI, 0.03-0.08 days; P < .001) but was not associated with increased risk of any of the other secondary outcomes. 3
74. American College of Radiology. ACR Appropriateness Criteria® Radiation Dose Assessment Introduction. Available at: Review/Other-Dx N/A To provide evidence-based guidelines on exposure of patients to ionizing radiation. No abstract available. 4