MRI Evaluation of the Pregnant Patient with Suspected Appendicitis: Imaging Considerations and Alternative Explanations for Abdominal and Pelvic Pain

  • Daniel R. LudwigEmail author
  • Richard Tsai
  • Demetrios A. Raptis
  • Vincent M. Mellnick


Learning Objectives: To review the indications for magnetic resonance imaging (MRI) in the pregnant patient with suspected appendicitis, discuss imaging protocols, demonstrate MRI findings of acute appendicitis, and illustrate alternative explanations for abdominal and pelvic pain in the pregnant patient.

Summary: Appendicitis is the most common condition necessitating emergency surgery in the pregnant patient. The clinical presentation is non-specific, and the diagnosis difficult to make, in part due to displacement of the appendix by the gravid uterus, and the range of symptomatology encountered during normal pregnancy. MRI is our first-line diagnostic test due to its lack of ionizing radiation and the high non-visualization rate of the appendix using ultrasound. At our institution, MRI is performed at 1.5 T without oral or intravenous contrast using a comprehensive multi-planar multi-weighted imaging protocol, which includes single-shot T2-weighted images, T2-weighted images with fat saturation, balanced steady-state free-precession gradient-echo images, and T1-weighted gradient-echo images with fat saturation. Magnetic resonance (MR) findings of appendicitis include a thick-walled and enlarged (size ≥8 mm) appendix, periappendiceal inflammation, and the presence of an appendicolith or appendicoliths. Non-visualization of the appendix on MRI, in contradistinction to ultrasound, has very high negative predictive value for acute appendicitis. MRI can be used to simultaneously evaluate for alternative obstetric and non-obstetric explanations for abdominal and pelvic pain.

Conclusion: MRI has a high diagnostic accuracy for acute appendicitis, and can be used to simultaneously evaluate for an alternative explanation for abdominal pain in the pregnant patient. MRI should be considered the first-line diagnostic test in the pregnant patient with suspected appendicitis.


Pregnancy Abdominal pain Appendicitis Magnetic resonance imaging 



Disclosure of Conflicts of Interest: The authors have no relevant relationships to disclose.


  1. 1.
    Tracey M, Fletcher HS. Appendicitis in pregnancy. Am Surg. 2000;66(6):555–9.PubMedGoogle Scholar
  2. 2.
    Abbasi N, Patenaude V, Abenhaim HA. Management and outcomes of acute appendicitis in pregnancy-population-based study of over 7000 cases. BJOG. 2014;121(12):1509–14.PubMedCrossRefGoogle Scholar
  3. 3.
    Mourad J, Elliott JP, Erickson L, Lisboa L. Appendicitis in pregnancy: new information that contradicts long-held clinical beliefs. Am J Obstet Gynecol. 2000;182(5):1027–9.PubMedCrossRefGoogle Scholar
  4. 4.
    Cappell MS, Friedel D. Abdominal pain during pregnancy. Gastroenterol Clin North Am. 2003;32(1):1–58.PubMedCrossRefGoogle Scholar
  5. 5.
    Mayer IE, Hussain H. Abdominal pain during pregnancy. Gastroenterol Clin North Am. 1998;27(1):1–36.PubMedCrossRefGoogle Scholar
  6. 6.
    Theilen L, Mellnick V, Shanks A, Tuuli M, Odibo A, Macones G, et al. Acute appendicitis in pregnancy: predictive clinical factors and pregnancy outcomes. Am J Perinatol. 2016;34(6):523–8.PubMedCrossRefGoogle Scholar
  7. 7.
    Lee SL, Walsh AJ, Ho HS. Computed tomography and ultrasonography do not improve and may delay the diagnosis and treatment of acute appendicitis. Arch Surg. 2001;136(5):556–62.PubMedCrossRefGoogle Scholar
  8. 8.
    Kessler N, Cyteval C, Gallix B, Lesnik A, Blayac P-M, Pujol J, et al. Appendicitis: evaluation of sensitivity, specificity, and predictive values of US, Doppler US, and laboratory findings. Radiology. 2004;230(2):472–8.PubMedCrossRefGoogle Scholar
  9. 9.
    Oto A, Srinivasan PN, Ernst RD, Koroglu M, Cesani F, Nishino T, et al. Revisiting MRI for appendix location during pregnancy. AJR Am J Roentgenol. 2006;186(3):883–7.PubMedCrossRefGoogle Scholar
  10. 10.
    Wu V, Armson BA. Appendicitis in pregnancy: clinical presentation and perinatal outcome. J SOGC. 1999;21(14):1328–33.CrossRefGoogle Scholar
  11. 11.
    Babaknia A, Parsa H, Woodruff JD. Appendicitis during pregnancy. Obstet Gynecol. 1977;50(1):40–4.PubMedGoogle Scholar
  12. 12.
    Tamir IL, Bongard FS, Klein SR. Acute appendicitis in the pregnant patient. Am J Surg. 1990;160(6):571–6.PubMedCrossRefGoogle Scholar
  13. 13.
    Ueberrueck T, Koch A, Meyer L, Hinkel M, Gastinger I. Ninety-four appendectomies for suspected acute appendicitis during pregnancy. World J Surg. 2004;28(5):508–11.PubMedCrossRefGoogle Scholar
  14. 14.
    McGory ML, Zingmond DS, Tillou A, Hiatt JR, Ko CY, Cryer HM. Negative appendectomy in pregnant women is associated with a substantial risk of fetal loss. J Am Coll Surg. 2007;205(4):534–40.PubMedCrossRefGoogle Scholar
  15. 15.
    Bendeck SE, Nino-Murcia M, Berry GJ, Jeffrey RB. Imaging for suspected appendicitis: negative appendectomy and perforation rates. Radiology. 2002;225(1):131–6.PubMedCrossRefGoogle Scholar
  16. 16.
    Coursey CA, Nelson RC, Patel MB, Cochran C, Dodd LG, DeLong DM, et al. Making the diagnosis of acute appendicitis: do more preoperative CT scans mean fewer negative appendectomies? A 10-year study. Radiology. 2010;254(2):460–8.PubMedCrossRefGoogle Scholar
  17. 17.
    Patel SJ, Reede DL, Katz DS, Subramaniam R, Amorosa JK. Imaging the pregnant patient for nonobstetric conditions: algorithms and radiation dose considerations. Radiographics. 2007;27(6):1705–22.PubMedCrossRefGoogle Scholar
  18. 18.
    Lehnert BE, Gross JA, Linnau KF, Moshiri M. Utility of ultrasound for evaluating the appendix during the second and third trimester of pregnancy. Emerg Radiol. 2012;19(4):293–9.PubMedCrossRefGoogle Scholar
  19. 19.
    Garcia EM, Camacho MA, Karolyi DR, Kim DH, Cash BD, Chang KJ, et al. ACR appropriateness criteria® right lower quadrant pain-suspected appendicitis. J Am Coll Radiol. 2018;15(11):S373–87.PubMedCrossRefGoogle Scholar
  20. 20.
    Israel GM, Malguria N, McCarthy S, Copel J, Weinreb J. MRI vs. ultrasound for suspected appendicitis during pregnancy. J Magn Reson Imaging. 2008;28(2):428–33.PubMedCrossRefGoogle Scholar
  21. 21.
    Spalluto LB, Woodfield CA, DeBenedectis CM, Lazarus E. MR imaging evaluation of abdominal pain during pregnancy: appendicitis and other nonobstetric causes. Radiographics. 2012;32(2):317–34.PubMedCrossRefGoogle Scholar
  22. 22.
    Tocchio S, Kline-Fath B, Kanal E, Schmithorst VJ, Panigrahy A. MRI evaluation and safety in the developing brain. Semin Perinatol. 2015;39(2):73–104.PubMedPubMedCentralCrossRefGoogle Scholar
  23. 23.
    Patenaude Y, Pugash D, Lim K, Morin L, Lim K, Bly S, et al. The use of magnetic resonance imaging in the obstetric patient. J Obstet Gynaecol Can. 2014;36(4):349–55.PubMedCrossRefGoogle Scholar
  24. 24.
    ACR. ACR–SPR practice parameter for the safe and optimal performance of fetal magnetic resonance imaging (MRI). 2014. Accessed 25 Mar 2019.
  25. 25.
    Ray JG, Vermeulen MJ, Bharatha A, Montanera WJ, Park AL. Association between MRI exposure during pregnancy and fetal and childhood outcomes. JAMA. 2016;316(9):952–61.PubMedCrossRefGoogle Scholar
  26. 26.
    Fraum TJ, Ludwig DR, Bashir MR, Fowler KJ. Gadolinium-based contrast agents: a comprehensive risk assessment. J Magn Reson Imaging. 2017;46(2):338–53.PubMedCrossRefGoogle Scholar
  27. 27.
    Duke E, Kalb B, Arif-Tiwari H, Daye ZJ, Gilbertson-Dahdal D, Keim SM, et al. A systematic review and meta-analysis of diagnostic performance of MRI for evaluation of acute appendicitis. AJR Am J Roentgenol. 2016;206(3):508–17.PubMedCrossRefGoogle Scholar
  28. 28.
    Kaushal P, Somwaru AS, Charabaty A, Levy AD. MR enterography of inflammatory bowel disease with endoscopic correlation. Radiographics. 2017;37(1):116–31.PubMedCrossRefGoogle Scholar
  29. 29.
    Fidler JL, Guimaraes L, Einstein DM. MR imaging of the small bowel. Radiographics. 2009;29(6):1811–25.PubMedCrossRefGoogle Scholar
  30. 30.
    Rimola J, Rodriguez S, García-Bosch O, Ordás I, Ayala E, Aceituno M, et al. Magnetic resonance for assessment of disease activity and severity in ileocolonic Crohn’s disease. Gut. 2009;58(8):1113–20.PubMedCrossRefGoogle Scholar
  31. 31.
    Kinsella SM, Lee A, Spencer JA. Maternal and fetal effects of the supine and pelvic tilt positions in late pregnancy. Eur J Obstet Gynecol Reprod Biol. 1990;36(1–2):11–7.PubMedCrossRefGoogle Scholar
  32. 32.
    Yong FA, Alvarado AM, Wang H, Tsai J, Estes NC. Appendectomy: a risk factor for colectomy in patients with clostridium difficile. Am J Surg. 2015;209(3):532–5.PubMedCrossRefPubMedCentralGoogle Scholar
  33. 33.
    Bhangu A, Søreide K, Di Saverio S, Assarsson JH, Drake FT. Acute appendicitis: modern understanding of pathogenesis, diagnosis, and management. Lancet. 2015;386(10000):1278–87.PubMedCrossRefPubMedCentralGoogle Scholar
  34. 34.
    Baird DLH, Simillis C, Kontovounisios C, Rasheed S, Tekkis PP. Acute appendicitis. BMJ. 2017;357:j1703.PubMedCrossRefPubMedCentralGoogle Scholar
  35. 35.
    Swischuk LE, Chung DH, Hawkins HK, Jadhav SP, Radhakrishnan R. Non-fecalith-induced appendicitis: etiology, imaging, and pathology. Emerg Radiol. 2015;22(6):643–9.PubMedCrossRefPubMedCentralGoogle Scholar
  36. 36.
    Marudanayagam R, Williams GT, Rees BI. Review of the pathological results of 2660 appendicectomy specimens. J Gastroenterol. 2006;41(8):745–9.PubMedCrossRefPubMedCentralGoogle Scholar
  37. 37.
    Tsai R, Raptis C, Fowler KJ, Owen JW, Mellnick VM. MRI of suspected appendicitis during pregnancy: interradiologist agreement, indeterminate interpretation and the meaning of non-visualization of the appendix. Br J Radiol. 2017;90(1079):20170383.PubMedPubMedCentralCrossRefGoogle Scholar
  38. 38.
    Willekens I, Peeters E, Maeseneer MD, de Mey J. The normal appendix on CT: does size matter? PLoS One. 2014;9(5):e96476.PubMedPubMedCentralCrossRefGoogle Scholar
  39. 39.
    Jan Y-T, Yang F-S, Huang J-K. Visualization rate and pattern of normal appendix on multidetector computed tomography by using multiplanar reformation display. J Comput Assist Tomogr. 2005;29(4):446–51.PubMedCrossRefGoogle Scholar
  40. 40.
    Atema JJ, van Rossem CC, Leeuwenburgh MM, Stoker J, Boermeester MA. Scoring system to distinguish uncomplicated from complicated acute appendicitis. Br J Surg. 2015;102(8):979–90.PubMedCrossRefGoogle Scholar
  41. 41.
    Yoon HM, Kim JH, Lee JS, Ryu J-M, Kim DY, Lee J-Y. Pediatric appendicitis with appendicolith often presents with prolonged abdominal pain and a high risk of perforation. World J Pediatr. 2018;14(2):184–90.PubMedCrossRefGoogle Scholar
  42. 42.
    Abdeen N, Naz F, Linthorst R, Khan U, Dominguez PC, Koujok K, et al. Clinical impact and cost-effectiveness of noncontrast MRI in the evaluation of suspected appendiceal abscesses in children. J Magn Reson Imaging. 2019;49(7):e241–9.PubMedCrossRefGoogle Scholar
  43. 43.
    Kim HY, Park JH, Lee YJ, Lee SS, Jeon J-J, Lee KH. Systematic review and meta-analysis of CT features for differentiating complicated and uncomplicated appendicitis. Radiology. 2017;287(1):104–15.PubMedCrossRefGoogle Scholar
  44. 44.
    Pedrosa I, Levine D, Eyvazzadeh AD, Siewert B, Ngo L, Rofsky NM. MR imaging evaluation of acute appendicitis in pregnancy. Radiology. 2006;238(3):891–9.PubMedCrossRefGoogle Scholar
  45. 45.
    Rettenbacher T, Hollerweger A, Macheiner P, Rettenbacher L, Frass R, Schneider B, et al. Presence or absence of gas in the appendix: additional criteria to rule out or confirm acute appendicitis—evaluation with US. Radiology. 2000;214(1):183–7.PubMedCrossRefGoogle Scholar
  46. 46.
    Hong H-S, Cho HS, Woo JY, Lee Y, Yang I, Hwang J-Y, et al. Intra-appendiceal air at CT: is it a useful or a confusing sign for the diagnosis of acute appendicitis? Korean J Radiol. 2016;17(1):39–46.PubMedPubMedCentralCrossRefGoogle Scholar
  47. 47.
    Chin CM, Lim KL. Appendicitis: atypical and challenging CT appearances: resident and fellow education feature. Radiographics. 2015;35(1):123–4.PubMedCrossRefGoogle Scholar
  48. 48.
    Shin I, An C, Lim JS, Kim M-J, Chung YE. T1 bright appendix sign to exclude acute appendicitis in pregnant women. Eur Radiol. 2017;27(8):3310–6.PubMedCrossRefGoogle Scholar
  49. 49.
    Al-Katib S, Sokhandon F, Farah M. MRI for appendicitis in pregnancy: is seeing believing? Clinical outcomes in cases of appendix nonvisualization. Abdom Radiol (NY). 2016;41(12):2455–9.CrossRefGoogle Scholar
  50. 50.
    Kearl YL, Claudius I, Behar S, Cooper J, Dollbaum R, Hardasmalani M, et al. Accuracy of magnetic resonance imaging and ultrasound for appendicitis in diagnostic and nondiagnostic studies. Acad Emerg Med. 2016;23(2):179–85.PubMedCrossRefGoogle Scholar
  51. 51.
    Kim DW, Suh CH, Yoon HM, Kim JR, Jung AY, Lee JS, et al. Visibility of normal Appendix on CT, MRI, and sonography: a systematic review and meta-analysis. AJR Am J Roentgenol. 2018;211(3):W140–50.PubMedCrossRefGoogle Scholar
  52. 52.
    Vu L, Ambrose D, Vos P, Tiwari P, Rosengarten M, Wiseman S. Evaluation of MRI for the diagnosis of appendicitis during pregnancy when ultrasound is inconclusive. J Surg Res. 2009;156(1):145–9.PubMedCrossRefGoogle Scholar
  53. 53.
    Ramalingam V, LeBedis C, Kelly JR, Uyeda J, Soto JA, Anderson SW. Evaluation of a sequential multi-modality imaging algorithm for the diagnosis of acute appendicitis in the pregnant female. Emerg Radiol. 2015;22(2):125–32.PubMedCrossRefGoogle Scholar
  54. 54.
    Tirada N, Dreizin D, Khati NJ, Akin EA, Zeman RK. Imaging pregnant and lactating patients. Radiographics. 2015;35(6):1751–65.PubMedCrossRefGoogle Scholar
  55. 55.
    American College of Radiology, Committee on Drugs and Contrast Media. ACR manual on contrast media v10.3 [Internet]. 2018. Accessed May 8 2019.
  56. 56.
    Poletti P-A, Botsikas D, Becker M, Picarra M, Rutschmann OT, Buchs NC, et al. Suspicion of appendicitis in pregnant women: emergency evaluation by sonography and low-dose CT with oral contrast. Eur Radiol. 2019;29(1):345–52.PubMedCrossRefGoogle Scholar
  57. 57.
    Pinto Leite N, Pereira JM, Cunha R, Pinto P, Sirlin C. CT Evaluation of appendicitis and its complications: imaging techniques and key diagnostic findings. Am J Roentgenol. 2005;185(2):406–17.CrossRefGoogle Scholar
  58. 58.
    Yarmish GM, Smith MP, Rosen MP, Baker ME, Blake MA, Cash BD, et al. ACR appropriateness criteria right upper quadrant pain. J Am Coll Radiol. 2014;11(3):316–22.PubMedPubMedCentralCrossRefGoogle Scholar
  59. 59.
    Bennett GL. Evaluating patients with right upper quadrant pain. Radiol Clin North Am. 2015;53(6):1093–130.PubMedCrossRefGoogle Scholar
  60. 60.
    Valdivieso V, Covarrubias C, Siegel F, Cruz F. Pregnancy and cholelithiasis: pathogenesis and natural course of gallstones diagnosed in early puerperium. Hepatology. 1993;17(1):1–4.PubMedGoogle Scholar
  61. 61.
    Maringhini A. Biliary sludge and gallstones in pregnancy: incidence, risk factors, and natural history. Ann Intern Med. 1993;119(2):116.PubMedCrossRefGoogle Scholar
  62. 62.
    Augustin G. Acute biliary tract diseases. In: Acute abdomen during pregnancy. Cham: Springer; 2014.CrossRefGoogle Scholar
  63. 63.
    Mendez-Sanchez N, Chavez-Tapia NC, Uribe M. Pregnancy and gallbladder disease. Ann Hepatol. 2006;5(3):227–30.PubMedCrossRefGoogle Scholar
  64. 64.
    Ghumman E, Barry M, Grace PA. Management of gallstones in pregnancy. Br J Surg. 1997;84(12):1646–50.PubMedCrossRefGoogle Scholar
  65. 65.
    Kaura SH, Haghighi M, Matza BW, Hajdu CH, Rosenkrantz AB. Comparison of CT and MRI findings in the differentiation of acute from chronic cholecystitis. Clin Imaging. 2013;37(4):687–91.PubMedCrossRefGoogle Scholar
  66. 66.
    Watanabe Y, Nagayama M, Okumura A, Amoh Y, Katsube T, Suga T, et al. MR imaging of acute biliary disorders. Radiographics. 2007;27(2):477–95.PubMedCrossRefGoogle Scholar
  67. 67.
    Date RS, Kaushal M, Ramesh A. A review of the management of gallstone disease and its complications in pregnancy. Am J Surg. 2008;196(4):599–608.PubMedCrossRefGoogle Scholar
  68. 68.
    Singh A, Mann HS, Thukral CL, Singh NR. Diagnostic accuracy of MRCP as compared to ultrasound/CT in patients with obstructive jaundice. J Clin Diagn Res. 2014;8(3):103–7.PubMedPubMedCentralGoogle Scholar
  69. 69.
    Chen W, Mo J-J, Lin L, Li C-Q, Zhang J-F. Diagnostic value of magnetic resonance cholangiopancreatography in choledocholithiasis. World J Gastroenterol. 2015;21(11):3351–60.PubMedPubMedCentralCrossRefGoogle Scholar
  70. 70.
    Irie H, Honda H, Kuroiwa T, Yoshimitsu K, Aibe H, Shinozaki K, et al. Pitfalls in MR cholangiopancreatographic interpretation. Radiographics. 2001;21(1):23–37.PubMedCrossRefGoogle Scholar
  71. 71.
    Mali P. Pancreatitis in pregnancy: etiology, diagnosis, treatment, and outcomes. Hepatobiliary Pancreat Dis Int. 2016;15(4):434–8.PubMedCrossRefGoogle Scholar
  72. 72.
    Miller FH, Keppke AL, Dalal K, Ly JN, Kamler V-A, Sica GT. MRI of pancreatitis and its complications: part 1, acute pancreatitis. AJR Am J Roentgenol. 2004;183(6):1637–44.PubMedCrossRefGoogle Scholar
  73. 73.
    Papadakis EP, Sarigianni M, Mikhailidis DP, Mamopoulos A, Karagiannis V. Acute pancreatitis in pregnancy: an overview. Eur J Obstet Gynecol Reprod Biol. 2011;159(2):261–6.PubMedCrossRefGoogle Scholar
  74. 74.
    Haram K, Svendsen E, Abildgaard U. The HELLP syndrome: clinical issues and management. A review. BMC Pregnancy Childbirth. 2009;9(1):8.PubMedPubMedCentralCrossRefGoogle Scholar
  75. 75.
    Nunes JO, Turner MA, Fulcher AS. Abdominal imaging features of HELLP syndrome: a 10-Year retrospective review. AJR Am J Roentgenol. 2005;185(5):1205–10.PubMedCrossRefGoogle Scholar
  76. 76.
    Longo SA, Moore RC, Canzoneri BJ, Robichaux A. Gastrointestinal conditions during pregnancy. Clin Colon Rectal Surg. 2010;23(2):80–9.PubMedPubMedCentralCrossRefGoogle Scholar
  77. 77.
    Webster P, Bailey M, Wilson J, Burke D. Small bowel obstruction in pregnancy is a complex surgical problem with a high risk of fetal loss. Ann R Coll Surg Engl. 2015;97(5):339–44.PubMedPubMedCentralCrossRefGoogle Scholar
  78. 78.
    Sivanesaratnam V. The acute abdomen and the obstetrician. Baillieres Best Pract Res Clin Obstet Gynaecol. 2000;14(1):89–102.PubMedCrossRefGoogle Scholar
  79. 79.
    Kakarla N, Dailey C, Marino T, Shikora SA, Chelmow D. Pregnancy after gastric bypass surgery and internal hernia formation. Obstet Gynecol. 2005;105(5 Pt 2):1195–8.PubMedCrossRefGoogle Scholar
  80. 80.
    Munkholm P, Langholz E, Nielsen OH, Kreiner S, Binder V. Incidence and prevalence of Crohn’s disease in the county of Copenhagen, 1962-87: a sixfold increase in incidence. Scand J Gastroenterol. 1992;27(7):609–14.PubMedCrossRefGoogle Scholar
  81. 81.
    Hashash JG, Kane S. Pregnancy and inflammatory bowel disease. Gastroenterol Hepatol. 2015;11(2):96–102.Google Scholar
  82. 82.
    Hatch Q, Champagne BJ, Maykel JA, Davis BR, Johnson EK, Bleier JI, et al. The impact of pregnancy on surgical Crohn disease: an analysis of the nationwide inpatient sample. J Surg Res. 2014;190(1):41–6.PubMedCrossRefGoogle Scholar
  83. 83.
    Gauci J, Sammut L, Sciberras M, Piscopo N, Micallef K, Cortis K, et al. Small bowel imaging in Crohn’s disease patients. Ann Gastroenterol. 2018;31(4):395–405.PubMedPubMedCentralGoogle Scholar
  84. 84.
    Heverhagen JT, Ishaque N, Zielke A, Bohrer T, Sitter H, Berthold LD, et al. Feasibility of MRI in the diagnosis of acute diverticulitis: initial results. MAGMA. 2001;12(1):4–9.PubMedCrossRefGoogle Scholar
  85. 85.
    Rao PM, Rhea JT, Wittenberg J, Warshaw AL. Misdiagnosis of primary epiploic appendagitis. Am J Surg. 1998;176(1):81–5.PubMedCrossRefGoogle Scholar
  86. 86.
    Meher S, Gibbons N, DasGupta R. Renal stones in pregnancy. Obstet Med. 2014;7(3):103–10.PubMedPubMedCentralCrossRefGoogle Scholar
  87. 87.
    Semins MJ, Matlaga BR. Management of urolithiasis in pregnancy. Int J Womens Health. 2013;5:599–604.PubMedPubMedCentralGoogle Scholar
  88. 88.
    Coursey CA, Casalino DD, Remer EM, Arellano RS, Bishoff JT, Dighe M, et al. ACR appropriateness criteria® acute onset flank pain--suspicion of stone disease. Ultrasound Q. 2012;28(3):227–33.PubMedCrossRefGoogle Scholar
  89. 89.
    Butler EL, Cox SM, Eberts EG, Cunningham FG. Symptomatic nephrolithiasis complicating pregnancy. Obstet Gynecol. 2000;96(5 Pt 1):753–6.PubMedGoogle Scholar
  90. 90.
    Rasmussen PE, Nielsen FR. Hydronephrosis during pregnancy: a literature survey. Eur J Obstet Gynecol Reprod Biol. 1988;27(3):249–59.PubMedCrossRefGoogle Scholar
  91. 91.
    Spencer JA, Chahal R, Kelly A, Taylor K, Eardley I, Lloyd SN. Evaluation of painful hydronephrosis in pregnancy: magnetic resonance urographic patterns in physiological dilatation versus calculous obstruction. J Urol. 2004;171(1):256–60.PubMedCrossRefGoogle Scholar
  92. 92.
    Muthusami P, Bhuvaneswari V, Elangovan S, Dorairajan LN, Ramesh A. The role of static magnetic resonance urography in the evaluation of obstructive uropathy. Urology. 2013;81(3):623–7.PubMedCrossRefGoogle Scholar
  93. 93.
    Mullins JK, Semins MJ, Hyams ES, Bohlman ME, Matlaga BR. Half Fourier single-shot turbo spin-echo magnetic resonance urography for the evaluation of suspected renal colic in pregnancy. Urology. 2012;79(6):1252–5.PubMedCrossRefGoogle Scholar
  94. 94.
    Woodfield CA, Lazarus E, Chen KC, Mayo-Smith WW. Abdominal pain in pregnancy: diagnoses and imaging unique to pregnancy—review. AJR Am J Roentgenol. 2010;194(6 Suppl):WS14–30.PubMedCrossRefGoogle Scholar
  95. 95.
    Rodgers SK, Chang C, DeBardeleben JT, Horrow MM. Normal and abnormal US findings in early first-trimester pregnancy: review of the society of radiologists in ultrasound 2012 consensus panel recommendations. Radiographics. 2015;35(7):2135–48.PubMedCrossRefPubMedCentralGoogle Scholar
  96. 96.
    Sivalingam VN, Duncan WC, Kirk E, Shephard LA, Horne AW. Diagnosis and management of ectopic pregnancy. J Fam Plann Reprod Health Care. 2011;37(4):231–40.PubMedPubMedCentralCrossRefGoogle Scholar
  97. 97.
    Alkatout I, Honemeyer U, Strauss A, Tinelli A, Malvasi A, Jonat W, et al. Clinical diagnosis and treatment of ectopic pregnancy. Obstet Gynecol Surv. 2013;68(8):571–81.PubMedCrossRefGoogle Scholar
  98. 98.
    Parker RA, Yano M, Tai AW, Friedman M, Narra VR, Menias CO. MR imaging findings of ectopic pregnancy: a pictorial review. Radiographics. 2012;32(5):1445–60.PubMedCrossRefGoogle Scholar
  99. 99.
    Wu Z, Zhang X, Xu P, Huang X. Clinical analysis of 50 patients with heterotopic pregnancy after ovulation induction or embryo transfer. Eur J Med Res. 2018;23(1):17.PubMedPubMedCentralCrossRefGoogle Scholar
  100. 100.
    Barrenetxea G, Barinaga-Rementeria L, Lopez de Larruzea A, Agirregoikoa JA, Mandiola M, Carbonero K. Heterotopic pregnancy: two cases and a comparative review. Fertil Steril. 2007;87(2):417.e9–417.e15.CrossRefGoogle Scholar
  101. 101.
    Petresin J, Wolf J, Emir S, Müller A, Boosz AS. Endometriosis-associated maternal pregnancy complications – case report and literature review. Geburtshilfe Frauenheilkd. 2016;76(8):902–5.PubMedPubMedCentralCrossRefGoogle Scholar
  102. 102.
    Leone Roberti Maggiore U, Ferrero S, Mangili G, Bergamini A, Inversetti A, Giorgione V, et al. A systematic review on endometriosis during pregnancy: diagnosis, misdiagnosis, complications and outcomes. Hum Reprod Update. 2016;22(1):70–103.PubMedCrossRefGoogle Scholar
  103. 103.
    Siegelman ES, Oliver ER. MR imaging of endometriosis: ten imaging pearls. Radiographics. 2012;32(6):1675–91.PubMedCrossRefGoogle Scholar
  104. 104.
    Woodward PJ, Sohaey R, Mezzetti TP. Endometriosis: radiologic-pathologic correlation. Radiographics. 2001;21(1):193–216.PubMedCrossRefGoogle Scholar
  105. 105.
    Hasson J, Tsafrir Z, Azem F, Bar-On S, Almog B, Mashiach R, et al. Comparison of adnexal torsion between pregnant and nonpregnant women. Am J Obstet Gynecol. 2010;202(6):536.e1–6.CrossRefGoogle Scholar
  106. 106.
    Mashiach S, Bider D, Moran O, Goldenberg M, Ben-Rafael Z. Adnexal torsion of hyperstimulated ovaries in pregnancies after gonadotropin therapy. Fertil Steril. 1990;53(1):76–80.PubMedCrossRefGoogle Scholar
  107. 107.
    Houry D, Abbott JT. Ovarian torsion: a fifteen-year review. Ann Emerg Med. 2001;38(2):156–9.CrossRefGoogle Scholar
  108. 108.
    Bider D, Mashiach S, Dulitzky M, Kokia E, Lipitz S, Ben-Rafael Z. Clinical, surgical and pathologic findings of adnexal torsion in pregnant and nonpregnant women. Surg Gynecol Obstet. 1991;173(5):363–6.PubMedGoogle Scholar
  109. 109.
    Rha SE, Byun JY, Jung SE, Jung JI, Choi BG, Kim BS, et al. CT and MR imaging features of adnexal torsion. Radiographics. 2002;22(2):283–94.PubMedCrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Daniel R. Ludwig
    • 1
    Email author
  • Richard Tsai
    • 2
  • Demetrios A. Raptis
    • 1
  • Vincent M. Mellnick
    • 1
  1. 1.Mallinckrodt Institute of RadiologyWashington University School of MedicineSaint LouisUSA
  2. 2.Advanced Radiology ConsultantsLeawoodUSA

Personalised recommendations