Top

Emergency Radiology

Published in:

01-04-2018 | Original Article

Secondary imaging for suspected appendicitis after equivocal ultrasound: time to disposition of MRI compared to CT

Authors: James F. Martin, David J. Mathison, Paul C. Mullan, Hansel J. Otero

Published in: Emergency Radiology | Issue 2/2018

Abstract

Purpose

The purpose of this study was to compare MRI to CT as a secondary imaging modality for children age 5 years and older with suspected appendicitis after an equivocal abdominal ultrasound in terms of (1) the time to ED disposition decision, (2) surgery consultation rate, and (3) imaging test accuracy.

Methods

We retrospectively studied children with suspected appendicitis and equivocal ultrasound results who underwent MR or CT as secondary imaging in a pediatric emergency department over two-consecutive 9-month periods. No oral or intravenous contrast was utilized for MRI. No sedation was utilized for any modality. Time of disposition is the time to admission or discharge order.

Results

Twenty-five patients underwent CT and 30 underwent MRI, with no significant difference in the median time from ultrasound to disposition between the CT (5.9 h, IQR 4.5, 8.4) and the MRI (5.9 h, IQR 4.6, 6.9) groups (p = 0.65). Fifteen patients had appendicitis. Of the 40 negative or equivocal studies, surgery was consulted for 79% in the CT and 48% in the MRI group (odds ratio 4.12, 95% CI 1.02–16.67). Diagnostic accuracy was as follows: MRI: sensitivity of 90%, specificity of 97.1%, positive predictive value of 90%, and negative predictive value of 97.1%. Abdominal CT: sensitivity of 88%, specificity of 98.6%, positive predictive value of 95.7%, and negative predictive value of 95.8%.

Conclusion

MRI is a feasible alternative to CT for secondary imaging in acute appendicitis for showing comparable ED throughput metrics and diagnostic accuracy, with added benefits of reduced radiation and avoidance of intravenous contrast.

Buckius MT, McGrath B, Monk J, Grim R, Bell T, Ahuja V (2012) Changing epidemiology of acute appendicitis in the United States: study period 1993–2008. J Surg Res 175(2):185–190. https://doi.org/10.1016/j.jss.2011.07.017 CrossRefPubMed

Smith MP, Katz DS, Lalani T, Carucci LR, Cash BD, Kim DH, Piorkowski RJ, Small WC, Spottswood SE, Tulchinsky M, Yaghmai V, Yee J, Rosen MP (2015) ACR Appropriateness Criteria® right lower quadrant pain—suspected appendicitis. Ultrasound 31(2):85–91. https://doi.org/10.1097/RUQ.0000000000000118 CrossRef

Doria AS, Moineddin R, Kellenberger CJ, Epelman M, Beyene J, Schuh S, Babyn PS, Dick PT (2006) US or CT for Diagnosis of Appendicitis in Children and Adults? A Meta-Analysis. Radiology 241(1):83–94. https://doi.org/10.1148/radiol.2411050913 CrossRefPubMed

Poortman P, Oostvogel HJ, Bosma E, Lohle PN, Cuesta MA, de Lange-de Klerk ES et al (2009) Improving diagnosis of acute appendicitis: results of a diagnostic pathway with standard use of ultrasonography followed by selective use of CT. J Am Coll Surg 208(3):434–441. https://doi.org/10.1016/j.jamcollsurg.2008.12.003 CrossRefPubMed

Toorenvliet BR, Wiersma F, Bakker RF, Merkus JW, Breslau PJ, Hamming JF (2010) Routine ultrasound and limited computed tomography for the diagnosis of acute appendicitis. World J Surg 34(10):2278–2285. https://doi.org/10.1007/s00268-010-0694-y CrossRefPubMedPubMedCentral

Binkovitz LA, Unsdorfer KM, Thapa P, Kolbe AB, Hull NC, Zingula SN et al (2015) Pediatric appendiceal ultrasound: accuracy, determinacy and clinical outcomes. Ped Radiology 45(13):1934–1944. https://doi.org/10.1007/s00247-015-3432-7 CrossRef

Krishnamoorthi R, Ramarajan N, Wang NE, Newman B, Rubesova E, Mueller CM, Barth RA (2011) 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):231–239. https://doi.org/10.1148/radiol.10100984 CrossRefPubMed

Lourenco P, Brown J, Leipsic J, Hague C (2016) The current utility of ultrasound in the diagnosis of acute appendicitis. Clin Imag 40(5):944–948. https://doi.org/10.1016/j.clinimag.2016.03.012 CrossRef

Dillman JR, Gadepalli S, Sroufe NS, Davenport MS, Smith EA, Chong ST, Mazza MB, Strouse PJ (2015) Equivocal pediatric appendicitis: unenhanced MR imaging protocol for nonsedated children—a clinical effectiveness study. Radiology 279(1):216–225. https://doi.org/10.1148/radiol.2015150941 CrossRefPubMed

10.

Fullerton K, Depinet H, Iyer S, Hall M, Herr S, Morton I et al (2016) Association of hospital resources and imaging choice for appendicitis in pediatric emergency departments. Acad Emerg Med 24(4):400–409CrossRef

11.

Aspelund G, Fingeret A, Gross E, Kessler D, Keung C, Thirumoorthi A, Oh PS, Behr G, Chen S, Lampl B, Middlesworth W, Kandel J, Ruzal-Shapiro C (2014) Ultrasonography/MRI vs CT for diagnosing appendicitis. Pediatrics 133(4):586–593. https://doi.org/10.1542/peds.2013-2128 CrossRefPubMed

12.

Orth RC, Guillerman RP, Zhang W, Masand P, Bisset IIIGS (2014) Prospective comparison of MR imaging and US for the diagnosis of pediatric appendicitis. Radiology 272(1):233–240. https://doi.org/10.1148/radiol.14132206 CrossRefPubMed

13.

Moore MM, Brian JM, Methratta ST, Hulse MA, Choudhary AK, Eggli KD et al (2014) MRI for clinically suspected pediatric appendicitis: case interpretation. Ped. Radiology 44(5):605–612

14.

Kulaylat AN, Moore MM, Engbrecht BW, Brian JM, Khaku A, Hollenbeak CS, Rocourt DV, Hulse MA, Olympia RP, Santos MC, Methratta ST, Dillon PW, Cilley RE (2015) An implemented MRI program to eliminate radiation from the evaluation of pediatric appendicitis. J Ped Surg 50(8):1359–1363. https://doi.org/10.1016/j.jpedsurg.2014.12.012 CrossRef

15.

Thieme ME, Leeuwenburgh MM, Valdehueza ZD, Bouman DE, de Bruin IG, Schreurs WH et al (2014) Diagnostic accuracy and patient acceptance of MRI in children with suspected appendicitis. Eur Rad 24(3):630–637. https://doi.org/10.1007/s00330-013-3044-2 CrossRef

16.

Moore MM, Gustas CN, Choudhary AK, Methratta ST, Hulse MA, Geeting G, et al. MRI for clinically suspected pediatric appendicitis: an implemented program. Ped Radiology 2012;42(9):1056–1063

17.

Johnson AK, Filippi CG, Andrews T, Higgins T, Tam J, Keating D, Ashikaga T, Braff SP, Gallant J (2012) Ultrafast 3-T MRI in the evaluation of children with acute lower abdominal pain for the detection of appendicitis. Am J Roent 198(6):1424–1430. https://doi.org/10.2214/AJR.11.7436 CrossRef

18.

Herliczek TW, Swenson DW, Mayo-Smith WW (2013) Utility of MRI after inconclusive ultrasound in pediatric patients with suspected appendicitis: retrospective review of 60 consecutive patients. Am J Roent. 200(5):969–973. https://doi.org/10.2214/AJR.12.10078 CrossRef

19.

Koning JL, Naheedy JH, Kruk PG (2015) Does abdominal pain duration affect the accuracy of first-line MRI for pediatric appendicitis? Abd Imag 40(2):352–359. https://doi.org/10.1007/s00261-014-0223-9 CrossRef

20.

Petkovska I, Martin DR, Covington MF, Urbina S, Duke E, Daye ZJ, Stolz l, Keim SM, Costello JR, Chundru S, Arif-Tiwari H, Gilbertson-Dahdal D, Gries L, Kalb B (2016) Accuracy of unenhanced MR imaging in the detection of acute appendicitis: single-institution clinical performance review. Radiology 279(2):451–460. https://doi.org/10.1148/radiol.2015150468 CrossRefPubMed

21.

Duke E, Kalb B, Arif-Tiwari H, Daye ZJ, Gilbertson-Dahdal D, Keim SM, Martin DR (2016) A systematic review and meta-analysis of diagnostic performance of MRI for evaluation of acute appendicitis. Am J Roent. 206(3):508–517. https://doi.org/10.2214/AJR.15.14544 CrossRef

22.

Moore MM, Kulaylat AN, Hollenbeak CS, Engbrecht BW, Dillman JR, Methratta ST. Magnetic resonance imaging in pediatric appendicitis: a systematic review. Ped Radiology 2016;46(6):928–939

23.

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 2009; 19(2):455–456, DOI: https://doi.org/10.1007/s00330-008-1176-6

24.

Estey A, Poonai N, Lim R (2014) Appendix not seen: the predictive value of secondary inflammatory sonographic signs. Acad Emerg Med 21(5):538–542CrossRef

25.

Ross MJ, Liu H, Netherton SJ, Eccles R, Chen PW, Boag G et al (2013) Outcomes of children with suspected appendicitis and incompletely visualized appendix on ultrasound. Pediatr Emerg Care 29(4):435–439CrossRef

26.

Nah SA, Ong SS, Lim WX, Amuddhu SK, Tang PH, Low Y (2017) Clinical relevance of the nonvisualized appendix on ultrasonography of the abdomen in children. J Pediatr 182:164–169. https://doi.org/10.1016/j.jpeds.2016.11.062 CrossRefPubMed

27.

Leung RS (2015) Radiation protection of the child from diagnostic imaging. Curr Pediatr Rev 11(4):235–242. https://doi.org/10.2174/1573396311666150729121930 CrossRefPubMed

28.

Sodhi K, Krishna S, Saxena AK, Sinha A, Khandelwal N, Lee EY (2015) Clinical application of ‘Justification’ and ‘Optimization’ principle of ALARA in pediatric CT imaging: how many children can be protected from unnecessary radiation? Eur J Radiol 84(9):1752–1757. https://doi.org/10.1016/j.ejrad.2015.05.030 CrossRefPubMed

29.

Georgiou R, Eaton S, Stanton M, Pierro A, Hall N (2017) Efficacy and safety of nonoperative treatment for acute appendicitis: a meta-analysis. Pediatrics 193(3):e20163003CrossRef

30.

Trout A, Sanchez R, Ladino-Torres M, Pai D, Strouse PA (2012) 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):813–823. https://doi.org/10.1007/s00247-012-2358-6 CrossRefPubMed

31.

Leeuwenburgh M, Wiarda B, Bipat S, Nio C, Bollen T, Kardux J et al (2012) Acute appendicitis on abdominal MR images: training readers to improve diagnostic accuracy. Radiology 264(2):455–463. https://doi.org/10.1148/radiol.12111896 CrossRefPubMed

32.

Leeuwenburgh M, Wiarda B, Jensch S, Van EH, Stockmann H, Gratama J et al (2014) Accuracy and interobserver agreement between MR-non-expert radiologists and MR-experts in reading MRI for suspected appendicitis. Eur J Radiol 83(1):103–110. https://doi.org/10.1016/j.ejrad.2013.09.022 CrossRefPubMed

Title: Secondary imaging for suspected appendicitis after equivocal ultrasound: time to disposition of MRI compared to CT
Authors: James F. Martin
David J. Mathison
Paul C. Mullan
Hansel J. Otero
Publication date: 01-04-2018
Publisher: Springer Berlin Heidelberg
Published in: Emergency Radiology / Issue 2/2018
Print ISSN: 1070-3004
Electronic ISSN: 1438-1435
DOI: https://doi.org/10.1007/s10140-017-1570-y

At a glance: The STEP trials

Springer Medicine

Secondary imaging for suspected appendicitis after equivocal ultrasound: time to disposition of MRI compared to CT

Abstract

Purpose

Methods

Results

Conclusion

At a glance: The STEP trials

Springer Medicine

Abstract

Purpose

Methods

Results

Conclusion

Please log in to get access to this content

Other articles of this Issue 2/2018

Recognizing intraventricular silicone

Multi-energy spectral CT: adding value in emergency body imaging

Accuracy of outside radiologists’ reports of computed tomography exams of emergently transferred patients

Dose monitoring in pediatric and young adult head and cervical spine CT studies at two emergency duty departments

MDCT of ductus diverticulum: 3D cinematic rendering to enhance understanding of anatomic configuration and avoid misinterpretation as traumatic aortic injury

Clinical and radiological diagnosis of gallstone ileus: a mini review