MR imaging in the triage of pregnant patients with acute abdominal and pelvic pain

Is Appendectomy During Late Stages of Pregnancy Associated with an Increased Cesarean Delivery Rate? - a Retrospective Analysis of One Center During 10 Years

Introduction

About one in 500 pregnant women requires a surgical intervention that is not pregnancy-related. One of the most common surgical interventions during pregnancy is appendectomy. The primary aim of this study was to assess surgical access of appendectomy during pregnancy and pregnancy outcome. Secondary outcomes were clinical symptoms and diagnostics as well as histopathological analysis.

Methods and Material

This is a single-center retrospective data analysis conducted at a tertiary perinatal center. A digital search of the hospital record archive was conducted focusing on pregnant women beyond 24 0/7 weeks of pregnancy encoding appendectomy. Descriptive statistical analysis was performed.

Results

Between January 2013 and January 2023, a total of 20 appendectomies were performed during pregnancy with gestational age beyond 24 0/7 weeks of pregnancy. All of them were performed as lower midline laparotomy. The rate of appendix perforation was 3/20 (15.0%). 19/20 patients (95.0%) delivered via cesarean. In 7/20 patients (35.0%) appendectomy was performed during cesarean delivery due to incidental finding of irritated or abnormal vermiform appendix. In the pathological work-up, only 2/7 (28.6%) of these subjects had inflammation.

Conclusion

In this small monocentric cohort, only open appendectomies were performed. Our data indicate that it is safe to perform open appendectomy during pregnancy if necessary. In this small patient group, there was an increase in simultaneous cesarean deliveries.

Findings on emergent magnetic resonance imaging in pregnant patients with suspected appendicitis: A single center perspective

This study's aim is to describe the imaging findings in pregnant patients undergoing emergent MRI for suspected acute appendicitis, and the various alternative diagnoses seen on those MRI scans. This is a single center retrospective analysis in which we assessed the imaging, clinical and pathological data for all consecutive pregnant patients who underwent emergent MRI for suspected acute appendicitis between April 2013 and June 2021. Out of 167 patients, 35 patients (20.9%) were diagnosed with acute appendicitis on MRI. Thirty patients (18%) were diagnosed with an alternative diagnosis on MRI: 17/30 (56.7%) patients had a gynecological source of abdominal pain (e.g. ectopic pregnancy, red degeneration of a leiomyoma); 8 patients (26.7%) had urological findings such as pyelonephritis; and 6 patients (20%) had gastrointestinal diagnoses (e.g. abdominal wall hernia or inflammatory bowel disease). Our conclusions are that MRI is a good diagnostic tool in the pregnant patient, not only in diagnosing acute appendicitis, but also in providing information on alternative diagnoses to acute abdominal pain. Our findings show the various differential diagnoses on emergent MRI in pregnant patients with suspected acute appendicitis, which may assist clinicians and radiologists is patient assessment and imaging utilization.

Acute Abdomen in Pregnancy: A Comprehensive Review of Diagnosis and Management

An unusual diagnostic and treatment challenge is presented by an acute abdomen during pregnancy. Obstetric factors and other causes unrelated to pregnancy also contribute to acute abdominal discomfort in pregnancy. Due to the changing clinical presentations brought on by the anatomical and physiological changes of pregnancy as well as the hesitation to utilize certain radiological studies out of concern about damaging the fetus, the diagnosis of the acute abdomen during pregnancy can be challenging. Delays in identification and treatment may have negative effects on the mother as well as the fetus. This review sheds light on the importance of anatomical and physiological considerations, early diagnoses, and understanding the various modalities and etiologies of acute abdomen in pregnancy (AAP). We then move on to discuss the various diagnostic techniques that can help the physician determine the causes and plan well-informed treatment. We examine and contrast different radiographic tests, including X-rays, computed tomography, magnetic resonance imaging, and ultrasound. We also talk about the various roles that these investigational methods can play in the evaluation and treatment throughout the duration of the pregnancy. The paper additionally addresses how to handle patients who appear with AAP and the different techniques used to treat them, including pre-operative laparoscopy. Before going over some more broad points that might be useful, we eventually dive into some of the more intriguing etiologies relating to AAP, such as isolated tubal torsion and neoplastic complications.

Adnexal torsion in pregnancy: A systematic review of case reports and case series

OBJECTIVES

This study aimed to investigate clinical presentations, surgical procedures and findings, complications, and predisposing factors of adnexal torsion in pregnant women.

METHODS

We searched PubMed/Medline, Embase, and Web of Science from January 2000 to March 2022. All case reports and case series with full-text English language reporting adnexal torsion in pregnant women were included. Medical history, clinical presentations, surgical procedures and findings, complications related to adnexal torsion, and predisposing factors were independently extracted by two investigators.

RESULTS

A total of 182 articles reporting 662 pregnant women with adnexal torsion were included. Most of the adnexal torsions occurred during the first trimester (54.63%), while others occurred during the second (26.36%) and third (19.00%) trimesters. The most common symptom of adnexal torsion was sudden-onset pain (80.60%). Enlargement of the adnexa was the most prevalent ultrasound finding in a twisted adnexa (95.20%). Additionally, about half of the patients had decreased blood flow in Doppler ultrasound (53.80%). Laparoscopic surgery was the favorite option (56.88%), while cystectomy and detorsion were the most commonly performed procedure (29.06%). Expectant management was reported in only 2.99% of the patients. In addition, the most common complications were preterm labor (27.58%) and emergent cesarean sections (25.28%).

CONCLUSIONS

Clinicians should think of adnexal torsion when pregnant women complain of sudden-onset pain. Then, using ultrasound, adnexal enlargement or masses should be explored seriously. They should take invasive and urgent therapy to preserve ovaries and prevent complications.

MRI as First Line Imaging for Suspected Acute Appendicitis during Pregnancy: Diagnostic Accuracy and level of Inter-Radiologist Agreement

OBJECTIVE

Evaluation of acute appendicitis (AA) in pregnancy is supported with diagnostic imaging. Typically, ultrasound (US) is performed first, and then often followed by magnetic resonance imaging (MRI) due to continued diagnostic uncertainty. The purpose of our study was to evaluate the sensitivity, specificity, and accuracy of US as compared to MRI and to evaluate the inter-radiologist agreement amongst body Radiologists with varying levels of expertise.

MATERIALS AND METHODS

We performed a retrospective study of 364 consecutive pregnant patients with clinical suspicion of AA at a single center over a 6-year period. Sensitivity, Specificity, accuracy, positive and negative predictive values were calculated for US and MRI. Inter Radiologist agreement was determined using Cohen's Kappa analysis between original interpreting Radiologist and retrospective review by expert Radiologist.

RESULTS

Thirty-one of 364 patients (8.5%) underwent appendectomy based on preoperative diagnosis, with confirmation of acute appendicitis (AA) by pathology in 19. US was able to visualize the appendix in only 6 (1.65%), 5 of whom had appendicitis. 141 patients underwent MRI, and correctly diagnosed appendicitis in 9. No patient with a negative MRI diagnosis had AA. The sensitivity, and negative predictive value for diagnosing AA with MRI was 100%. The MRI inter-reader agreement for appendix visualization and overall accuracy were 87.9 and 98% with Cohen Kappa of 0.7 and 0.56 respectively.

CONCLUSIONS

Our data suggests that MRI should be considered the first line imaging modality in pregnant patients suspected of having AA. Body Radiologists with varied levels of experience in MRI readouts had substantial agreement.

Magnetic resonance imaging (MRI) for diagnosis of acute appendicitis

BACKGROUND

Appendicitis remains a difficult disease to diagnose, and imaging adjuncts are commonly employed. Magnetic resonance imaging (MRI) is an imaging test that can be used to diagnose appendicitis. It is not commonly regarded as a first-line imaging test for appendicitis, but the reported diagnostic accuracy in some studies is equivalent to computed tomography (CT) scans. As it does not expose patients to radiation, it is an attractive imaging modality, particularly in women and children.

OBJECTIVES

The primary objective was to determine the diagnostic accuracy of MRI for detecting appendicitis in all patients. Secondary objectives: To investigate the accuracy of MRI in subgroups of pregnant women, children, and adults. To investigate the potential influence of MRI scanning variables such as sequences, slice thickness, or field of view.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase until February 2021. We searched the references of included studies and other systematic reviews to identify further studies. We did not exclude studies that were unpublished, published in another language, or retrospective.

SELECTION CRITERIA

We included studies that compared the outcome of an MRI scan for suspected appendicitis with a reference standard of histology, intraoperative findings, or clinical follow-up. Three study team members independently filtered search results for eligible studies.

DATA COLLECTION AND ANALYSIS

We independently extracted study data and assessed study quality using the Quality Assessment of Studies of Diagnostic Accuracy - Revised (QUADAS-2) tool. We used the bivariate model to calculate pooled estimates of sensitivity and specificity.

MAIN RESULTS

We identified 58 studies with sufficient data for meta-analysis including a total of 7462 participants (1980 with and 5482 without acute appendicitis). Estimates of sensitivity ranged from 0.18 to 1.0; estimates of specificity ranged from 0.4 to 1.0. Summary sensitivity was 0.95 (95% confidence interval (CI) 0.94 to 0.97); summary specificity was 0.96 (95% CI 0.95 to 0.97). Sensitivity and specificity remained high on subgroup analysis for pregnant women (sensitivity 0.96 (95% CI 0.88 to 0.99); specificity 0.97 (95% CI 0.95 to 0.98); 21 studies, 2282 women); children (sensitivity 0.96 (95% CI 0.95 to 0.97); specificity 0.96 (95% CI 0.92 to 0.98); 17 studies, 2794 children); and adults (sensitivity 0.96 (95% CI 0.93 to 0.97); specificity 0.93 (95% CI 0.80 to 0.98); 9 studies, 1088 participants), as well as different scanning techniques. In a hypothetical cohort of 1000 patients, there would be 12 false-positive results and 30 false-negative results. Methodological quality of the included studies was poor, and the risk of bias was high or unclear in 53% to 83% of the QUADAS-2 domains.

AUTHORS' CONCLUSIONS

MRI appears to be highly accurate in confirming and excluding acute appendicitis in adults, children, and pregnant women regardless of protocol. The methodological quality of the included studies was generally low due to incomplete and low standards of follow-up, so summary estimates of sensitivity and specificity may be biased. We could not assess the impact and direction of potential bias given the very low number of high-quality studies. Studies comparing MRI protocols were few, and although we found no influence of MRI protocol variables on the summary estimates of accuracy, our results do not rule out that some MRI protocols are more accurate than others.

Pregnant Women After Bariatric Surgery: Diagnostic Accuracy of Magnetic Resonance Imaging for Small Bowel Obstruction

BACKGROUND

Small bowel obstruction (SBO) is a late complication of Roux-en-Y gastric bypass (RYGB). In non-pregnant patients, computed tomography (CT) is the first choice of imaging. During pregnancy, magnetic resonance imaging (MRI) is preferred to limit exposure to ionizing radiation. However, literature regarding the diagnostic accuracy of MRI for SBO is scarce.

OBJECTIVE

To describe the diagnostic accuracy of MRI for SBO during pregnancy.

METHODS

Pregnant women with RYGB suspected for SBO who presented at our center between September 2015 and April 2020 and who received an MRI scan (index) and underwent surgery (reference) were included. Original reports were retrospectively evaluated. Available MRI scans were structurally reinterpreted by two experienced radiologists. Statistical analysis included sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and Cohen's kappa.

RESULTS

Twenty-seven original MRI reports were included. Twenty-four (89%) MRIs were of good quality. Sensitivity was 67% (confidence interval (CI) 0.43-0.85), specificity 67% (CI 0.13-0.98), PPV 93% (CI 0.66-0.99), and NPV 22% (CI 0.04-0.60). MRI was unable to detect SBO in 1 out of 3 patients. The presence of swirl sign, SBO sign, or clustered loop sign increases the likelihood of SBO. The interobserver agreement was overall wide, with the highest score for swirl sign (κ 0.762).

DISCUSSION

MRI is a safe and feasible alternative for CT. The value is doubtful as diagnostic accuracy shows wide ranges with considerable variability in the interobserver agreement. We would cautiously advise to perform MRI in case of a mild clinical presentation, but in case of a severe clinic, the diagnostic laparoscopy should remain the gold standard.

Maternal hydronephrosis in pregnant women without ureteral stones and characteristics of symptomatic cases who need treatment: A single-center prospective study with 1026 pregnant women

PURPOSE

The aim of this study is to determine the proportion of maternal hydronephrosis and symptomatic cases requiring treatment in pregnant women without ureteral stones and the characteristics of these cases.

MATERIALS AND METHODS

Between February 2018 and April 2019, all pregnant women followed for pregnancy in obstetrics and outpatient policlinic were evaluated prospectively. Maternal hydronephrosis rate, degree of hydronephrosis and side, symptomatic hydronephrosis rate, maximum renal anteroposterior diameter of renal pelvis and visual analogue scale were detected. Symptomatic patients were treated conservatively or surgically. Findings in both treatment groups were analyzed by t-test or Chi-squared test. Pearson or Spermean's tests were used for correlation analyzes.

RESULTS

A total of 1026 pregnant women aged 18-45 (27.7 ± 5.2 years) were followed prospectively. The rate of maternal hydronephrosis was 28.7% and the rate of symptomatic hydronephrosis was 4.7%. Of the patients with symptomatic hydronephrosis, 73.4% (3.5% of total) were treated conservatively and 26.5% (1.3% of total) were treated surgically. There was a positive correlation between hydronephrosis and gestational week (p < 0.001), visual analogue scale (p < 0.001) and hematuria (p < 0.05). There was a negative correlation between hydronephrosis and maternal age (p < 0.05) and number of pregnancies (p < 0,001). The anteroposterior diameter of renal pelvis (p < 0.001), visual analogue scale (p < 0.05) and fetal body weight values (p < 0.05) on the right side were higher in the surgical treatment group than the conservative group.

CONCLUSIONS

The majority of cases with maternal hydronephrosis in pregnant women without ureteral stones are asymptomatic. Most symptomatic cases can also be treated conservatively. In cases requiring surgical treatment (1.3%), fetal body weight, visual analogue scale and anteroposterior renal pelvis diameter are higher.

Magnetic resonance imaging reduces the rate of unnecessary operations in pregnant patients with suspected acute appendicitis: a retrospective study

Purpose

This is a retrospective single-institution study performed to compare the rate of unnecessary operations in pregnant women with suspected acute appendicitis with and without the use of MRI.

Methods

The study subjects were all pregnant women with suspected acute appendicitis admitted to a tertiary institution from January 2012 to December 2019. If acute appendicitis was not excluded clinically and by ultrasound (US), laparoscopies were performed until May 2017 (US-only group). MRI was added as a diagnostic tool when US was inconclusive from May 2017 (US + MRI group). Surgery was considered unnecessary when no inflamed appendix was found. The rate of unnecessary surgery, postoperative complications, length of stay were analyzed.

Results

Seventy-six women were included in the study; 38 women in the US-only group and 38 women in the US + MRI group. There were no differences in admission characteristics between the groups. One of 38 women (2.6%) underwent unnecessary surgery in the US + MRI group vs. 10 of 38 (26.3%) in the US-only group (P = 0.007). The patients in the US + MRI group were significantly less likely to undergo a diagnostic operation than in the US-only group (5.26% vs. 55.3%, respectively; P < 0.001) and their hospital stay was significantly shorter (0.74 ± 1.64 days vs. 3.7 ± 3.0 days, respectively; P < 0.001). The obstetric outcomes were not different between the groups. MRI had a sensitivity of 83.3% and specificity of 100% in the series.

Conclusion

The rate of unnecessary surgery was significantly reduced in pregnant women, who underwent MRI after inconclusive transabdominal US.

Adnexal torsion in the third trimester of pregnancy: a case report and diagnostic value of MR imaging

BACKGROUND

The torsion of normal adnexa is rare during pregnancy, especially in the third trimester. Nonspecific symptoms and signs as well as the limitations of ultrasound (US) make the diagnosis difficult, resulting in the loss of adnexa and fetal compromise. The magnetic resonance imaging (MRI) features of the torsion of normal adnexa are not classically described during pregnancy and only reported in a few cases. We find some different MRI features of the torsion of normal adnexa in late pregnancy and its diagnosis and treatment values are discussed in our report.

CASE PRESENTATION

A 27-year-old woman at 31 + 5 weeks' gestation presented to the emergency department with a three-day history of the left lower abdominal pain. US discovered a mass of 87 × 61 mm in the left abdomen, but did not show whether the mass originated from the left ovary or the uterus. MRI showed the left ovary was increased in size to 82 × 42 × 85 mm with peripheral follicles. On fat-suppressed T2-weighted images, the signal intensity of the lesion was significantly decreased compared with the right ovary. The adjacent fallopian tube was found to be thickened. The radiologists diagnosed ovary infarction secondary to adnexal torsion. With the provisional diagnosis of adnexal torsion, the patient was taken to surgery. The left adnexal torsion was found during surgery. There was extensive hemorrhage and necrosis, so a left salpingo-oophorectomy was performed. The histopathology confirmed an extensively hemorrhagic fallopian tube and ovary with partial necrosis.

CONCLUSION

We believe MRI is helpful where US is indeterminate in diagnosis of the torsion of normal adnexa in advanced pregnancy. We found that aside from hyperintensity on fat-saturated T1-weighted images, the low signal intensity on T2-weighted images can also reflect adnexal hemorrhage in conjunction with the torsion of normal adnexa.

Emergent MRI for acute abdominal pain in pregnancy-review of common pathology and imaging appearance

Acute abdominal pain in pregnancy remains a clinically challenging presentation, often requiring imaging. The threat of morbidity and mortality to both mother and fetus necessitates quick and accurate imaging diagnosis, often via ultrasound. However, many of the common causes of acute abdominal pain are not readily diagnosed with sonography, and magnetic resonance imaging (MRI) is increasingly favored in this setting. The purpose of this review is to familiarize the reader with common pathologies which may be encountered in pregnant females presenting with acute abdominal pain requiring emergent MRI.

Pregnancy and appendicitis: a systematic review and meta-analysis on the clinical use of MRI in diagnosis of appendicitis in pregnant women

Background

The aim of this systematic review and meta-analysis was to evaluate the clinical use of MRI for the evaluation of acute appendicitis during pregnancy.

Methods

The searches were conducted by two independent researchers (MK, MS) to find the relevant studies published from 1/1/2009 until end of 30/12/2018. We searched for published literature in the English language in MEDLINE via PubMed, EMBASETM via Ovid, The Cochrane Library, and Trip database. For literature published in other languages, we searched national databases (Magiran and SID), KoreaMed, and LILACS. The keywords used in the search strategy are Pregnancy [MeSH], Pregnant [MeSH] OR-Magnetic resonance imaging [MeSH] OR-Appendicitis [MeSH] OR-Ultrasound, [MeSH] OR, imaging, MRI [MeSH] OR"،" and Right lower quadrant pain [MeSH]. The risk of bias of every article was evaluated by using QUADAS-2. On the basis of the results from the 2 × 2 tables, pooled measures for sensitivity, specificity, diagnostic odds ratio (DOR), and area under the curves (AUC) along with their 95% confidence intervals (CIs) were calculated using the DerSimonian Lair methodology.

Results

As many as 1164 studies were selected. After analyzing the correspondence of the studies with the required criteria, 19 studies were selected for the final review. For appendicitis in pregnancy, the MRI sensitivity was 91.8% at the 95% confidence interval of (95% CI 87.7-94.9%). At the confidence interval of 95%, the specificity was 97.9% (95% CI 0.97.2-100%). The risk of bias in the studies conducted was measured using the QUADAS-2 tool.

Conclusion

MRI has high sensitivity and specificity (91.8%, 97.9% respectively) for the diagnosis of acute appendicitis in pregnant patients with clinically suspected appendicitis. It is an excellent imaging technique in many instances, which does not expose a fetus, or the mother, to ionizing radiation, making it an excellent option for pregnant patients with suspected acute appendicitis.

Sonography of Acute Cholecystitis and Its Mimics

Right upper quadrant (RUQ) abdominal pain is a common complaint. Acute cholecystitis (AC) is the primary diagnostic consideration in most adults presenting with acute onset RUQ abdominal pain; however, a variety of other conditions can mimic AC. Abdominal ultrasound (US) receives the highest score for imaging appropriateness for these patients. This article reviews the sonographic findings of uncomplicated and complicated AC and provides practical technical tips. The radiologist should be familiar with conditions that can mimic AC, be able to suggest these alternative diagnoses when findings are present on US, and recommend additional tests or procedures, if needed.

Magnetic resonance imaging of common, uncommon, and rare implantation sites in ectopic pregnancy

OBJECTIVE

To review the MRI appearances of tubal and non-tubal implantation sites in ectopic pregnancy.

CONCLUSION

Transvaginal ultrasound is the primary imaging modality in ectopic pregnancy and MRI is used as a problem-solving tool in selected indications as detailed in the article. MRI features of tubal, interstitial, cervical, cesarean scar, cornual, ovarian, abdominal, and heterotopic pregnancies are provided to familiarize the radiologists with their appearances thereby assisting them in making early and accurate diagnosis.

Acute Nonhemorrhagic Adrenal Infarction in Pregnancy: 10-Year MRI Incidence and Patient Outcomes at a Single Institution

OBJECTIVE

The purpose of this study was to retrospectively investigate the MRI incidence of nonhemorrhagic adrenal infarction in pregnant women undergoing MRI evaluation of acute abdominal or flank pain, assess the MRI features quantitatively, and report patient outcomes.

MATERIALS AND METHODS

All abdominal MRI examinations of pregnant women with acute pain at one institution from May 2005 to April 2015 were reviewed. The adrenals were evaluated for abnormal morphologic and signal intensity characteristics described in the literature characterizing nonhemorrhagic adrenal infarction and were compared with the contralateral adrenal by paired t tests. The findings were correlated with clinical presentation. Patient demographics and outcomes were gathered from the medical record.

RESULTS

Findings of nonhemorrhagic adrenal infarction were present in 5 of 379 (1.3%) examinations of four pregnant patients (mean age, 28 years; range, 20.8-33.9 years; mean gestational age, 26 weeks; range, 16-35 weeks). MRI features included lengthening (mean, 39.8 versus 21.2 mm) (p = 0.005) and increased T2 signal intensity (p = 0.001) of the infarcted adrenal with surrounding edema and without T1 signal intensity suggesting hemorrhage. No alternative diagnosis was identified. All patients presented with severe acute abdominal or flank pain on the same side as the MRI findings, tenderness to palpation, and mild leukocytosis. All women delivered healthy infants.

CONCLUSION

Unilateral nonhemorrhagic adrenal infarction was identified in 1.3% of abdominal MRI examinations performed for pregnant women with acute abdominal or flank pain. Knowledge of the MRI characteristics of this entity is important for recognizing it and may prevent further potentially invasive tests, procedures, or missed diagnoses.

Differential diagnoses of magnetic resonance imaging for suspected acute appendicitis in pregnant patients

BACKGROUND

Accurate and timely diagnosis of acute surgical disease in pregnant patient is challenging. Although magnetic resonance imaging (MRI) is the most accurate modality to diagnose acute appendicitis in pregnant patients, it is often used as a last resort because of high cost and long scan time. We performed this study to analyze differential diagnoses of appendix MRI and to investigate if there are any blood tests that can predict surgical condition in pregnant patients.

METHODS

A retrospective, cross-sectional study was conducted on 46 pregnant patients who underwent non-enhanced appendix MRI in suspicion of acute appendicitis from 2010 to 2016. Differential diagnoses of appendix MRI were analyzed and blood tests were compared between those who had surgical and non-surgical disease.

RESULTS

Appendix MRI differentiated two surgical disease; acute appendicitis and ovarian torsion; and various non-surgical conditions such as uterine myoma, hydronephrosis, ureterolithiasis and diverticulitis among clinically suspected acute appendicitis in pregnancy. The diagnostic accuracy of MRI for acute appendicitis in this study was 93.5%. Patients who had surgical disease showed significantly higher WBC count (≥11,000/mm³), proportion of neutrophils in the WBC (≥79.9%), neutrophil-to-lymphocyte ratio (NLR≥6.4), levels of C-reactive protein (CRP≥1.82 mg/dL) and bilirubin (≥0.66 mg/dL) than those who had non-surgical disease.

CONCLUSION

MRI can reliably differentiate surgical conditions and several blood tests (WBC, proportion of neutrophils in the WBC, NLR, CRP, bilirubin) can help anticipate acute surgical condition among pregnant patients suspected to have acute appendicitis.

MRI of suspected appendicitis during pregnancy: interradiologist agreement, indeterminate interpretation and the meaning of non-visualization of the appendix

OBJECTIVE

To determine the degree of interradiologist agreement between the MRI features of appendicitis during pregnancy, the outcomes associated with an indeterminate interpretation and the negative predictive value of non-visualization of the appendix.

METHODS

Our study was approved by the institutional review board at the Washington University in St. Louis, Missouri (WUStL) and was HIPAA (Health Insurance Portability and Accountability Act of 1996)-compliant. The informed consent requirement was waived. Cases of suspected appendicitis during pregnancy evaluated using MRI were retrospectively identified using search queries. Scans were re-reviewed by two radiologists (7 and 9 years experience, respectively) to evaluate the interradiologist agreement of different MRI features of appendicitis during pregnancy (visualization of the appendix, appendiceal diameter, appendiceal wall thickening, periappendiceal fat stranding, fluid-filled appendix and periappendiceal fluid). The radiologists were blinded to patient outcome, patient intervention, laboratory data, demographic data and the original MRI reports. Clinical outcomes were documented by surgical pathology or clinical observation. Interradiologist agreement was analysed using Cohen's κ, while patient demographic and clinical data was analysed using Student's t-testing.

RESULTS

233 females with suspected appendicitis during pregnancy were evaluated using MRI over a 13-year period (mean age, 28.4 years; range, 17-38 years). There were 14 (6%) positive examinations for appendicitis during pregnancy, including 1 patient whose MRI was interpreted as negative, proven by surgical pathology. The presence of periappendiceal soft-tissue stranding and the final overall impression had the most interradiologist agreement (к = 0.81-1). There were no pregnant patients found to have acute appendicitis who had an indeterminate MR interpretation or when the appendix could not be visualized.

CONCLUSION

The final impression by the two retrospectively reviewing radiologists of MR examinations performed for suspected appendicitis during pregnancy had near-perfect agreement. In patients where the appendix could not be visualized or in patients that were interpreted as indeterminate, no patients had acute appendicitis. Advances in knowledge: MR impression for suspected appendicitis in the pregnant patient has high interradiologist agreement, and a non-visualized appendix or lack of inflammatory findings at the time of MR, reliably excludes surgical appendicitis.

Utility of Magnetic Resonance Imaging for the Diagnosis of Appendicitis During Pregnancy: A Canadian Experience

PURPOSE

The objective of the study was to evaluate the performance of magnetic resonance imaging (MRI) for the diagnosis of appendicitis during pregnancy.

METHODS

We conducted a retrospective review of all MRI scans performed at our institution, between 2006 and 2012, for the evaluation of suspected appendicitis in pregnant women. Details of the MRI scans performed were obtained from the radiology information system as well as details of any ultrasounds carried out for the same indication. Clinical and pathological data were obtained by retrospective chart review.

RESULTS

The study population comprised 63 patients, and 8 patients underwent a second MRI scan during the same pregnancy. A total of 71 MRI scans were reviewed. The appendix was identified on 40 scans (56.3%). Sensitivity of MRI was 75% and specificity was 100% for the diagnosis of appendicitis in pregnant women. When cases with right lower quadrant inflammatory fat stranding or focal fluid, without appendix visualization, were classified as positive for appendicitis, MRI sensitivity increased to 81.3% but specificity decreased to 96.4%.

CONCLUSIONS

MRI is sensitive and highly specific for the diagnosis of appendicitis during pregnancy and should be considered as a first line imaging study for this clinical presentation.

Clinical use of MRI for the evaluation of acute appendicitis during pregnancy

PURPOSE

The purpose of this study was to determine the diagnostic accuracy of MRI for detecting acute appendicitis in pregnancy in a multi-institution study involving general body MR readers with no specific expertise in MR imaging of the pregnant patient.

METHODS

Retrospective review of MRI examinations on PACS in 42 pregnant patients was evaluated for acute right lower quadrant pain. Three fellowship-trained general body radiologists analyzed the MRI examinations in consensus and attempted to localize the appendix, assess for features of appendicitis, and exclude alternative etiologies for the right lower quadrant pain.

RESULTS

Of the 42 MRI examinations, the readers noted 6 cases of acute appendicitis, 16 cases of a normal appendix, and 20 cases involving non-visualization of the appendix but where there were no secondary features of acute appendicitis. Based on the surgical data and clinical follow-up, there were 3 true-positive cases, 3 false-positive cases, 34 true-negative cases, and 2 false-negative cases of acute appendicitis on MRI. This yielded an accuracy of 88.1%, sensitivity of 60%, specificity of 91.9%, positive predictive value of 50%, and negative predictive value of 94.4% for the detection of acute appendicitis in the pregnant patient on MRI. Alternative etiologies for the right lower quadrant pain on MRI included torsion of an ovarian dermoid in 1 case and pyelonephritis in 1 case.

CONCLUSION

MRI is an excellent modality for excluding acute appendicitis in pregnant patients presenting with right lower quadrant pain.

A Systematic Review and Meta-Analysis of Diagnostic Performance of MRI for Evaluation of Acute Appendicitis

OBJECTIVE

A meta-analysis was performed to determine the accuracy of MRI in the diagnosis of acute appendicitis in the general population and in subsets of pregnant patients and children.

MATERIALS AND METHODS

A systematic search of the PubMed and EMBASE databases for articles published through the end of October 2014 was performed to identify studies that used MRI to evaluate patients suspected of having acute appendicitis. Pooled data for sensitivity, specificity, and positive and negative predictive values were calculated.

RESULTS

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.

CONCLUSION

MRI has a high accuracy for the diagnosis of acute appendicitis, for a wide range of patients, and may be acceptable for use as a first-line diagnostic test.

Our ultrasonographic experience in the management of symptomatic hydronephrosis during pregnancy

INTRODUCTION

The aim of the present study was to document the role of ultrasound in the diagnosis and management of symptomatic hydronephrosis during pregnancy.

METHODS

In this study, we reviewed 36 consecutive cases of pregnant women whose pregnancy was complicated by symptomatic hydronephrosis. In all patients, management was initially conservative (analgesics and fluids) after hospitalization. The following criteria were used to indicate double-J stent placement under US guidance rather than a conservative treatment: persistent pain with no improvement after conservative treatment, progressive hydronephrosis (>2 cm dilatation of the renal pelvis) or presence of uterine contractions.

RESULTS

The mean patient's age was 25 years (17-35) and gestational age at clinical presentation was 24 weeks (13-37). 81 % of cases had a renal pelvis dilatation >2 cm, while in only 19 % of cases there was a hydronephrosis between 1 and 2 cm in diameter; however, calculi were confirmed only in 25 patients. 28 patients required an invasive management with double-J stent insertion under US guidance. The sensitivity and specificity of US in the etiological diagnosis of hydronephrosis during pregnancy was 83 and 91 %, respectively.

CONCLUSION

Conservative management with medical therapy and observation should be the first-line treatment approach. In our opinion a rapid ureteral decompression with the insertion of a ureteral double-J stent, under US visualization, is the safest method in the treatment of pregnant women with obstructed renal systems.

Magnetic Resonance Imaging of Abdominal and Pelvic Pain in the Pregnant Patient

The utility of MR imaging in evaluating abdominal and pelvic pain in the pregnant patient is discussed. Details regarding the indications, technical aspects, and imaging findings of various common abdominal and pelvic abnormalities in pregnancy are reviewed.

ACR Appropriateness Criteria® Right Lower Quadrant Pain--Suspected Appendicitis

The most common cause of acute right lower quadrant (RLQ) pain requiring surgery is acute appendicitis (AA). This narrative's focus is on imaging procedures in the diagnosis of AA, with consideration of other diseases causing RLQ pain. In general, Computed Tomography (CT) is the most accurate imaging study for evaluating suspected AA and alternative etiologies of RLQ pain. Data favor intravenous contrast use for CT, but the need for enteric contrast when intravenous contrast is used is not strongly favored. Radiation exposure concerns from CT have led to increased investigation in minimizing CT radiation dose while maintaining diagnostic accuracy and in using algorithms with ultrasound as a first imaging examination followed by CT in inconclusive cases. In children, ultrasound is the preferred initial examination, as it is nearly as accurate as CT for the diagnosis of AA in this population and without ionizing radiation exposure. In pregnant women, ultrasound is preferred initially with MRI as a second imaging examination in inconclusive cases, which is the majority.The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Optimizing diagnostic imaging in the emergency department

While emergency diagnostic imaging use has increased significantly, there is a lack of evidence for corresponding improvements in patient outcomes. Optimizing emergency department (ED) diagnostic imaging has the potential to improve the quality, safety, and outcomes of ED patients, but to date, there have not been any coordinated efforts to further our evidence-based knowledge in this area. The objective of this article is to discuss six aspects of diagnostic imaging to provide background information on the underlying framework for the 2015 Academic Emergency Medicine consensus conference, "Diagnostic Imaging in the Emergency Department: A Research Agenda to Optimize Utilization." The consensus conference aims to generate a high priority research agenda for emergency diagnostic imaging that will inform the design of future investigations. The six components herein will serve as the group topics for the conference: 1) patient-centered outcomes research; 2) clinical decision rules; 3) training, education, and competency; 4) knowledge translation and barriers to image optimization; 5) use of administrative data; and 6) comparative effectiveness research: alternatives to traditional CT use.

Loss of renal India ink artifact-a useful radiological sign for obstructive hydronephrosis in pregnancy

Magnetic resonance imaging is a useful tool for investigating causes of abdominal pain in pregnancy. Differentiating between physiologic hydronephrosis of pregnancy and pathologic hydronephrosis can be challenging for clinicians and radiologists. This report describes loss of the India ink artifact around the obstructed kidney as a novel and potentially useful radiological sign, which may be of value in the evaluation of abdominal pain and hydronephrosis in pregnancy.

Appendectomy and Pregnancy: Gestational Age Does Not Affect the Position of the Incision

The position of the base of the appendix during advancing gestational age is based on inadequate data. Therefore, the proper location for an appendectomy incision during pregnancy is highly unclear. This study investigated the location of the appendix during pregnancy to determine the optimal location for an incision in pregnant patients with appendicitis relative to McBurney's point. Magnetic resonance images (MRIs) were reviewed independently by two fellowship-trained abdominal MRI radiologists blinded to the imaging report. The distance of the appendix from anatomic landmarks was measured in a total of 114 pregnant women with an abdominal or pelvic MRI who were admitted between 2001 and 2011 at a Level I trauma center. Patients with a history of appendectomy were excluded. The distance from the base of the appendix to McBurney's point changed over the course of the gestation by only 1.2 cm and which did not amount to a clinically or statistically significant change in position. Our data provide evidence that there is minimal upward or lateral displacement of the appendix during pregnancy, and therefore its distance from the McBurney's point remains essentially unchanged. These findings justify the use of the McBurney's incision for appendectomy during pregnancy regardless of the trimester.

Utility of magnetic resonance imaging for suspected appendicitis in pregnant women

OBJECTIVE

The purpose of this study was to estimate the rate and risk of appendix nonvisualization and alternative diagnoses made with magnetic resonance imaging (MRI) for suspected appendicitis in pregnant women.

STUDY DESIGN

We performed a retrospective cohort study of consecutive pregnant women who underwent MRI for suspected appendicitis at a single center from 2007-2012. Data on clinical presentation, imaging, and surgical pathologic evidence were extracted from electronic medical records. Odds ratios estimated risk factors for nondiagnosis. Radiologic diagnoses were identified, and rates of diagnoses were calculated. Subgroup analysis was performed among women who underwent initial imaging with ultrasound scanning.

RESULTS

Over the 5-year period, 171 pregnant women underwent MRI for suspected appendicitis. The rate of nonvisualization was 30.9% (n = 53). Of the remaining 118 women with a visualized appendix, 18 women had imaging findings that were consistent with appendicitis and underwent appendectomy. Twelve cases of appendicitis were confirmed on pathologic evaluation (66.7%). Women with nonvisualization of the appendix on MRI were more likely to be beyond the first trimester (odds ratio, 2.1; 95% confidence interval, 1.0-4.5). Seventy-four women had disease diagnosed on MRI (43.3%). In the group of 43 women who had a nondiagnostic ultrasound scanning before the MRI, the rate of subsequent diagnostic MRI was 65% (n = 28).

CONCLUSION

MRI yields a high diagnostic rate and accuracy in pregnant women with suspected appendicitis and provides alternative diagnoses to guide further management. Given the high rate of appendix nonvisualization on ultrasound scanning that has been reported in the literature, we recommend MRI as the imaging modality of choice for this population in settings in which MRI is readily available.

Magnetic resonance enterography in pregnant women with Crohn's disease: case series and literature review

BACKGROUND

Evaluation of pregnant women with known or suspected Crohn's disease (CD) remains a challenge. Magnetic Resonance Enterography (MRE) is a promising diagnostic tool in these patients; however, the clinical data on MRE utilization in pregnancy is scarce. The aim of the study was to describe the experience with MRE in pregnant CD patients in a tertiary referral center.

METHODS

We retrospectively reviewed MRE studies performed in pregnant women with known or suspected CD that were performed between January 2007 and November 2012. Imaging findings, clinical management and outcome were extracted from patient's file and electronic records. Image quality was evaluated.

RESULTS

Ten studies of 9 patients were included. MRE protocol was modified to maximize maternal and fetal safety, and intravenous gadolinium was not used. In 7 patients, CD diagnosis was previously established; six were admitted with clinical symptoms consistent with CD exacerbation, and an additional patient with a recurrent groin abscess without apparent luminal symptoms. In all seven patients, imaging features consistent with active CD were detected; new penetrating complications were detected in 4 patients. Two patients underwent MRE for suspected CD which was not comforted by study results. The clinical management was significantly impacted by MRE results in all positive cases. The image quality of the fast MRE sequences obtained without gadolinium was satisfactory and allowed meaningful interpretation.

CONCLUSION

MRE with an adapted protocol for pregnancy is a reliable imaging modality to manage in pregnant women with known or suspected CD.

Diagnosis of a sigmoid volvulus in pregnancy: ultrasonography and magnetic resonance imaging findings

Sigmoid volvulus complicating pregnancy is a rare, non-obstetric cause of abdominal pain that requires prompt surgical intervention (decompression) to avoid intestinal ischemia and perforation. We report the case of a 31-week pregnant woman with abdominal pain and subsequent development of constipation. Preoperative diagnosis was achieved using magnetic resonance imaging and ultrasonography: the large bowel distension and a typical whirl sign - near a sigmoid colon transition point - suggested the diagnosis of sigmoid volvulus. The decision to refer the patient for emergency laparotomy was adopted without any ionizing radiation exposure, and the pre-operative diagnosis was confirmed after surgery. Imaging features of sigmoid volvulus and differential diagnosis from other non-obstetric abdominal emergencies in pregnancy are discussed in our report, with special emphasis on the diagnostic capabilities of ultrasonography and magnetic resonance imaging.

ACR appropriateness criteria right upper quadrant pain

Acute right upper quadrant pain is a common presenting symptom in patients with acute cholecystitis. When acute cholecystitis is suspected in patients with right upper quadrant pain, in most clinical scenarios, the initial imaging modality of choice is ultrasound. Although cholescintigraphy has been shown to have slightly higher sensitivity and specificity for diagnosis, ultrasound is preferred as the initial study for a variety of reasons, including greater availability, shorter examination time, lack of ionizing radiation, morphologic evaluation, confirmation of the presence or absence of gallstones, evaluation of bile ducts, and identification or exclusion of alternative diagnoses. CT or MRI may be helpful in equivocal cases and may identify complications of acute cholecystitis. When ultrasound findings are inconclusive, MRI is the preferred imaging test in pregnant patients who present with right upper quadrant pain. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Nuclear medicine tests for acute gastrointestinal conditions

Acute cholecystitis (AC) and lower-gastrointestinal (GI) bleeding are 2 emergencies commonly encountered in nuclear medicine. Evidence of AC on hepatobiliary scintigraphy (HBS) allows for confident diagnosis and provides support for definitive surgical treatment. Proper patient preparation is essential for HBS including fasting and the use of pharmacologic adjuncts is sometimes required. Pharmacologic adjuncts may also be administered during HBS to shorten the length of the examination and increase its specificity. In the interpretation of HBS, there are several sources of false-positive results to be aware of, most commonly chronic cholecystitis. False-negative results on HBS are usually the result of mistaking another structure, such as a dilated cystic duct, for the gallbladder. Abdominal ultrasound is the appropriate initial test in patients with suspected AC, but HBS is an excellent second tier test for the diagnosis of AC in the work-up of indeterminate cases by sonography. GI bleeding scintigraphy plays an important role in the evaluation and management of patients with acute lower-GI bleeding. Scintigraphy serves to localize sites of active GI bleeding and stratify those patients who would benefit from aggressive treatment (surgery or arteriography) vs those who can be managed medically. Pretest involvement of respective services is critical for successful bleeding site confirmation and therapy by interventional radiology or surgery or both. Single photon emission computed tomography/computed tomography erythrocyte scintigraphy has demonstrated superior accuracy and precision over planar scintigraphy in the diagnosis of acute GI bleeding. Additionally, single photon emission computed tomography/computed tomography scintigraphy of GI bleeding provides useful supplemental anatomical information that benefits patient management.

Integrating MR imaging into the clinical workup of pregnant patients suspected of having appendicitis is associated with a lower negative laparotomy rate: single-institution study

PURPOSE

To determine if integrating magnetic resonance (MR) imaging into the workup of right lower quadrant pain in pregnant patients was associated with improved outcomes as measured by the negative laparotomy rate (NLR) and the perforation rate (PR).

MATERIALS AND METHODS

Institutional review board approval was obtained for this retrospective review of medical records. Two hundred sixty-seven pregnant patients who underwent either surgery (n = 82) or an MR imaging examination (n = 217) because of suspicion of appendicitis between January 1, 1996, and August 31, 2011, were identified. Relevant ultrasonographic and MR imaging reports were classified as showing true-positive, false-positive, true-negative, false-negative, or equivocal findings. MR imaging utilization was analyzed to define pre- and post-MR imaging cohorts. NLR and PR were calculated for both cohorts and were compared by using a Fisher exact probability test. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for MR imaging were calculated.

RESULTS

MR imaging was introduced into the clinical workup in 2004. From 1996 to 2003, the NLR for pregnant patients was 55% (17 of 31), and the PR was 21% (three of 14). From 2004 to 2011, the NLR was 29% (15 of 51), and the PR was 26% (nine of 35). The 47% decline in the NLR ([55%-29%]/55%) was statistically significant (P = .02). The change in PR was not significant (P > .99). The sensitivity, specificity, PPV, and NPV of MR imaging in the diagnosis of appendicitis were 89% (17 of 19), 97% (187 of 193), 74% (17 of 23), and 99% (187 of 189), respectively.

CONCLUSION

The routine incorporation of MR imaging into the clinical workup for suspicion of appendicitis in pregnant patients at this institution was associated with a decrease in the NLR of 47% without a significant change in the PR.

SUPPLEMENTAL MATERIAL

http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12121027/-/DC1.

[Unclear abdominal pain in central emergency admissions. An algorithm]

One of the chief complaints in the emergency department is abdominal pain which is associated with a large spectrum of possible underlying diagnoses. Life-threatening diseases have to be identified urgently to treat them rapidly either conservatively or by surgical intervention. The algorithm presented in this article starts with the triage in the emergency department. After triage the first step in the algorithm is an interdisciplinary communication to start the standardized diagnostic process which includes medical history, clinical examination, laboratory analyses, ultrasound and electrocardiogram. Further diagnostic escalation should be done in unspecific and urgent cases of abdominal pain after consulting a specialist. In approximately 30 % of patients with abdominal pain on admittance to an emergency department the cause remains unclear after undergoing the diagnostic process. In these cases it can be useful for risk stratification to transfer the patient to a ward related to the emergency department for observation und further diagnostics.

Nonobstetric abdominal pain and surgical emergencies in pregnancy

The focus of this article is the evaluation and management of pregnant patients with nonobstetric abdominal pain and surgical emergencies. The anatomic and physiologic changes that occur during pregnancy can cause difficulties in interpreting patients' signs and symptoms in emergency departments. This article reviews some of the common causes of nonobstetric abdominal pain and surgical emergencies that present to emergency departments and discusses some of the literature surrounding the use of imaging modalities during pregnancy. After a review of these changes and their causes, imaging modalities that can be used for the assessment are discussed.