Cost-effectiveness of preoperative imaging for appendicitis after indeterminate ultrasonography in the second or third trimester of pregnancy

A Systematic Review of Methods and Practice for Integrating Maternal, Fetal, and Child Health Outcomes, and Family Spillover Effects into Cost-Utility Analyses

BACKGROUND

Maternal-perinatal interventions delivered during pregnancy or childbirth have unique characteristics that impact the health-related quality of life (HRQoL) of the mother, fetus, and newborn child. However, maternal-perinatal cost-utility analyses (CUAs) often only consider either maternal or child health outcomes. Challenges include, but are not limited to, measuring fetal, newborn, and infant health outcomes, and assessing their impact on maternal HRQoL. It is also important to recognize the impact of maternal-perinatal health on family members' HRQoL (i.e., family spillover effects) and to incorporate these effects in maternal-perinatal CUAs.

OBJECTIVE

The aim was to systematically review the methods used to include health outcomes of pregnant women, fetuses, and children and to incorporate family spillover effects in maternal-perinatal CUAs.

METHODS

A literature search was conducted in Medline, Embase, EconLit, Cochrane Collection, Cumulative Index to Nursing and Allied Health Literature (CINAHL), International Network of Agencies for Health Technology Assessment (INAHTA), and the Pediatric Economic Database Evaluation (PEDE) databases from inception to 2020 to identify maternal-perinatal CUAs that included health outcomes for pregnant women, fetuses, and/or children. The search was updated to December 2022 using PEDE. Data describing how the health outcomes of mothers, fetuses, and children were measured, incorporated, and reported along with the data on family spillover effects were extracted.

RESULTS

Out of 174 maternal-perinatal CUAs identified, 62 considered the health outcomes of pregnant women, and children. Among the 54 quality-adjusted life year (QALY)-based CUAs, 12 included fetal health outcomes, the impact of fetal loss on mothers' HRQoL, and the impact of neonatal demise on mothers' HRQoL. Four studies considered fetal health outcomes and the effects of fetal loss on mothers' HRQoL. One study included fetal health outcomes and the impact of neonatal demise on maternal HRQoL. Furthermore, six studies considered the impact of neonatal demise on maternal HRQoL, while four included fetal health outcomes. One study included the impact of fetal loss on maternal HRQoL. The remaining 26 only included the health outcomes of pregnant women and children. Among the eight disability-adjusted life year (DALY)-based CUAs, two measured fetal health outcomes. Out of 174 studies, only one study included family spillover effects. The most common measurement approach was to measure the health outcomes of pregnant women and children separately. Various approaches were used to assess fetal losses in terms of QALYs or DALYs and their impact on HRQoL of mothers. The most common integration approach was to sum the QALYs or DALYs for pregnant women and children. Most studies reported combined QALYs and incremental QALYs, or DALYs and incremental DALYs, at the family level for pregnant women and children.

CONCLUSIONS

Approximately one-third of maternal-perinatal CUAs included the health outcomes of pregnant women, fetuses, and/or children. Future CUAs of maternal-perinatal interventions, conducted from a societal perspective, should aim to incorporate health outcomes for mothers, fetuses, and children when appropriate. The various approaches used within these CUAs highlight the need for standardized measurement and integration methods, potentially leading to rigorous and standardized inclusion practices, providing higher-quality evidence to better inform decision-makers about the costs and benefits of maternal-perinatal interventions. Health Technology Assessment agencies may consider providing guidance for interventions affecting future lives in future updates.

Adult appendicitis: Clinical practice guidelines from the French Society of Digestive Surgery and the Society of Abdominal and Digestive Imaging

INTRODUCTION

The French Society of Digestive Surgery (SFCD) and the Society of Abdominal and Digestive Imaging (SIAD) have collaborated to propose recommendations for clinical practice in the management of adult appendicitis.

METHODS

An analysis of the literature was carried out according to the methodology of the French National Authority for Health (HAS). A selection was performed from collected references and then a manual review of the references listed in the selected articles was made in search of additional relevant articles. The research was limited to articles whose language of publication was English or French. Articles focusing on the pediatric population were excluded. Based on the literature review, the working group proposed recommendations whenever possible. These recommendations were reviewed and approved by a committee of experts.

RESULTS

Recommendations about appendicitis in adult patients were proposed with regard to clinical, laboratory and radiological diagnostic modalities, treatment strategy for uncomplicated and complicated appendicitis, surgical technique, and specificities in the case of macroscopically healthy appendix, terminal ileitis and appendicitis in the elderly and in pregnant women.

CONCLUSION

These recommendations for clinical practice may be useful to the surgeon in optimizing the management of acute appendicitis in adults.

Efficiency of Diagnostic Testing for Helicobacter pylori Infections-A Systematic Review

Background: The most recommended treatment for a Helicobacter pylori infection is high doses of combined antibiotics. The objective of this article is to perform a systematic review of the economic evaluation studies applied to assess the efficiency of diagnostic testing for H. pylori infections, so that their main characteristics can be identified and to learn from the literature how the antimicrobial resistance (AMR) issue is incorporated into these economic evaluations. Methods: We conducted a systematic review to compare the costs and clinical effectiveness of diagnostic strategies for H. pylori infections. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and extracted the items from the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist. Results: We found thirteen articles that were of good quality according to CHEERS: six studies focused on diagnostics of Helicobacter pylori infections associated with dyspepsia and four on duodenal ulcers. Testing was found to be the most cost-effective strategy in eight articles. Four studies considered AMR. Conclusions: Testing was more cost-effective than empirical treatment, except in cases of high prevalence (as with developing countries) or when patients could be stratified according to their comorbidities. The introduction of AMR into the model may change the efficiency of the testing strategy.

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.

Cost Saving of Short Hospitalization Nonoperative Management for Acute Uncomplicated Appendicitis

BACKGROUND

Nonoperative management (NOM) of uncomplicated appendicitis has gained recognition as an alternative to surgery. In the largest published randomized trial (Appendicitis Acuta), patients received a 3-d hospital stay for intravenous antibiotics; however, cost implications for health care systems remain unknown. We hypothesized short stay protocols would be cost saving compared with a long stay protocol.

MATERIALS AND METHODS

We constructed a Markov model comparing the cost of three protocols for NOM of acute uncomplicated appendicitis: (1) long stay (3-d hospitalization), (2) short stay (1-d hospitalization), and (3) emergency department (ED) discharge. The long stay protocol was modeled on data from the APPAC trial. Model variables were abstracted from national database and literature review. One-way and two-way sensitivity analyses were performed to determine the impact of uncertainty on the model.

RESULTS

The long stay treatment protocol had a total 5-y projected cost of $10,735 per patient. The short stay treatment protocol costs $8026 per patient, and the ED discharge protocol costs $6,825, which was $2709 and $3910 less than the long stay protocol, respectively. One-way sensitivity analysis demonstrated that the relative risk of treatment failure with the short stay protocol needed to exceed 6.3 (absolute risk increase of 31%) and with the ED discharge protocol needed to exceed 8.75 (absolute risk increase of 45%) in order for the long stay protocol to become cost saving.

CONCLUSIONS

Short duration hospitalization protocols to treat appendicitis nonoperatively with antibiotics are cost saving under almost all model scenarios. Future consideration of patient preferences and health-related quality of life will need to be made to determine if short stay treatment protocols are cost-effective.

Nonfetal Imaging During Pregnancy: Acute Abdomen/Pelvis

Abdominal pain is a common occurrence in pregnant women and may have a variety of causes, including those that are specific to pregnancy (eg, round ligament pain in the first trimester) and the wide range of causes of abdominal pain that affect men and women who are not pregnant (eg, appendicitis, acute cholecystitis). Noncontrast magnetic resonance (MR) imaging is increasingly performed to evaluate pregnant women with abdominal pain, either as the first-line test or as a second test following ultrasonography. The imaging appearance of causes of abdominal pain in pregnant women are reviewed with an emphasis on noncontrast MR imaging.

Unilateral live twin tubal ectopic pregnancy presenting at 12 weeks of gestation: A case report

RATIONALE

Abdominal pain in pregnancy represents a demanding diagnostic challenge in the emergency department (ED) due to the extensive list of differential diagnoses to be considered, coupled with the possibility of each disease having nonclassical, atypical signs and symptoms, resultant from the patient's pregnant state. Additionally, emergency physicians (EPs) face limitations on investigative imaging modalities because of the need to minimize fetal radiation exposure. EPs have to tackle this diagnostic challenge while performing a balancing act to maximize both maternal and fetal outcomes in a time-sensitive manner, becauser any delays in decision-making at the ED may threaten the safety of mother and child. Two common causes of abdominal pain in pregnancy presenting to the ED are acute appendicitis and ectopic pregnancy. The latter is almost always diagnosed by 10 weeks of gestation. Here, we report an extremely rare case of unilateral live spontaneous twin tubal ectopic pregnancy presenting past 12 weeks of gestation, diagnosed after magnetic resonance imaging (MRI) of the abdomen.

PATIENT CONCERNS

A 37-year-old gravida 2 para 1 at 12 weeks and 6 days of gestation presented to our ED with a 2-day history of right iliac fossa pain, not associated with vaginal bleeding, fever, diarrhea, and vomiting. On examination, she was tachycardic (pulse rate 124 beats/min) and hypertensive (blood pressure 142/88 mm Hg). There was marked tenderness and guarding at the lower abdomen.

DIAGNOSES

Blood investigations were unremarkable, while abdominal ultrasonography found a live twin gestation with foetal heartbeats of 185 and 180 beats/min. MRI of the abdomen revealed an empty uterine cavity; 2 amniotic sacs and fetuses of diameter 10 cm, and a single placenta were noted in the right uterine adnexa. The patient was diagnosed with right live monochorionic diamniotic twin tubal pregnancy.

INTERVENTION

Our patient underwent emergency laparoscopic right salpingectomy.

OUTCOMES

The operation was successful and her postoperative care remained uneventful up to discharge.

LESSONS

Ectopic pregnancy cannot be ruled out based on prior normal antenatal examinations and gestational age of >10 weeks. EPs should not hesitate to order MRI scans for further evaluation if ultrasonography and laboratory findings are equivocal.

Ethical challenges in regionalization of pediatric surgical care

PURPOSE OF REVIEW

Rapid advancement in the field of pediatric surgery has resulted in unprecedented opportunities to advance the care of children. However, assuring that the highest quality, most appropriate care is available to all pediatric patients remains challenging. Regionalization of care has been proposed as a means of obtaining this critical goal. In this review, we discuss the ethical challenges associated with regionalization of pediatric surgical care.

RECENT FINDINGS

Regionalization of pediatric surgical care is associated with improved patient outcomes. Over half of pediatric surgeons favor regionalization of care. Despite these findings, regionalization of care may be associated with inequitable distribution of resources, financial and emotional burdens for patients and families, and surgeon dissatisfaction and technical decline.

SUMMARY

Regionalization of pediatric surgical care is fraught with complex ethical issues. Development of a system of pediatric surgery networks may offer a solution to these challenges.

Approaching zero: Implications of a computed tomography reduction program for pediatric appendicitis evaluation

PURPOSE

Because of awareness of iatrogenic radiation exposure, there is a national trend of diminishing computed tomography (CT) use for pediatric suspected appendicitis. The purpose of this study was to evaluate the effects of a CT reduction program for evaluation of appendicitis.

METHODS

A multidisciplinary group (emergency medicine, radiology, and surgery) at a children's hospital developed a reduction program which included: ultrasound (U/S) first (2012), magnetic resonance imaging (MRI) second (2014), and standardized U/S reports (2016). Imaging modality, negative appendectomy rate, time from first image to incision, and imaging costs were evaluated over time.

RESULTS

Of the 571 patients evaluated from 2012 to 2016, there was a significant decrease in CT use and increase U/S and MRI use over the study period (all p<0.01). CT use approached zero in 2016. Time from first image to incision (median 10.7h, IQR 5.6-15.5) and negative appendectomy rate (mean 3.7±0.2%) did not change. Median imaging costs ($88, IQR $52-$169) and radiology percent of total costs (range 0.8%-3.9%) increased over time (both p<0.01).

CONCLUSION

Approaching zero CT use for evaluation of pediatric appendicitis is possible through a multidisciplinary protocol without impacting clinical outcomes. However, increased MRI use led to higher costs. Cost-effectiveness of replacing CT with MRI warrants further study.

TYPE OF STUDY

Retrospective comparative study.

LEVEL OF EVIDENCE

Level III.

Laparoscopy in the second and third trimesters of pregnancy for abdominal surgical emergencies

OBJECTIVE

To assess complications and outcomes of pregnancies following laparoscopic abdominal surgery during the second and third trimesters of pregnancy.

MATERIAL AND METHODS

Retrospective single-center study of 23 cases of laparoscopic surgery in the second or third trimesters of pregnancy between January 2005 and May 2016.

RESULTS

The laparoscopies were performed between 15 and 33 weeks of gestation, a mean of 23 weeks+2 days, with 6 cases in the 3rd trimester. The operations were: 11 cholecystectomies, 6 appendectomies, 1 intestinal occlusion (volvulus on a gastric band), 3 adnexal torsions, 1 ovarian cyst and 1 paratubal cyst with torsion. No secondary laparotomy was required. The postoperative courses were favorable in most cases. However, 3 appendectomies were complicated, one by chorioamnionitis and miscarriage at 20½ weeks of gestation and 2 by right iliac fossa abscesses requiring percutaneous radiological drainage, one of these women delivered a healthy term baby and the other had chorioamnionitis and preterm delivery at 34 weeks, followed by neonatal death.

CONCLUSION

Laparoscopy can be safely performed for surgical indications in the second and third trimesters of pregnancy. In case of abdominal symptoms, a timely diagnosis is required to decide whether or not to operate and imaging should not be withheld particularly in case of suspected appendicitis which has a high risk of complications.

Clinical Relevance of the Nonvisualized Appendix on Ultrasonography of the Abdomen in Children

OBJECTIVES

To evaluate the clinical relevance of the nonvisualized appendix on ultrasound imaging in children with right lower quadrant pain.

STUDY DESIGN

We reviewed 1359 children admitted for abdominal pain between January and December 2013 who had abdominal ultrasound imaging for right lower quadrant pain. Patients who had scans for genitourinary symptoms or intussusception were excluded from the study. When the appendix was not visualized, secondary signs indicating right lower quadrant inflammatory pathology were noted.

RESULTS

Of all admissions for abdominal pain, 810 had ultrasound scans. Thirty-eight did not evaluate the appendix and 131 were excluded for suspected intussusception, leaving 641 reports for children with a median age of 10.8 years (range, 1.3-21.3); 297 were boys (46.3%). There were 17 of 160 patients with a nonvisualized appendix (10.6%) who underwent appendectomy. Of these, 14 had secondary signs on ultrasound imaging and 3 (1.9%) had normal ultrasound reports. The 3 patients with normal ultrasound imaging had computed tomography imaging confirming appendicitis. There were 51 patients with a partially visualized appendix. The segment of appendix that could be seen was normal in 34 patients, none of whom had appendectomy. The remaining 17 had appendectomy, in whom the appendix seemed to be inflamed in 13 and equivocal in 4, all with histologically confirmed appendicitis. Overall, 232 children underwent appendectomy; 58 had no ultrasound imaging done, and 5 had a histologically normal appendix (overall negative appendectomy rate, 2.2%). Only 35 of 1359 patients (0.03%) had computed tomography scans.

CONCLUSION

In patients with a nonvisualized appendix on ultrasound imaging and no evidence of secondary inflammatory changes, the likelihood of appendicitis is less than 2%. Generous use of ultrasonography as an adjunct to clinical examination can achieve low negative appendectomy rates without underdiagnosis of acute appendicitis.

Magnetic resonance imaging of acute appendicitis in pregnancy: a 5-year multiinstitutional study

OBJECTIVE

The purpose of this study was to determine the diagnostic performance of magnetic resonance imaging (MRI) in the diagnosis of acute appendicitis during pregnancy in a multiinstitutional study.

STUDY DESIGN

In this multicenter retrospective study, the cases of pregnant women who underwent MRI evaluation of abdominal or pelvic pain and who had clinical suspicion of acute appendicitis between June 1, 2009, and July 31, 2014, were reviewed. All MRI examinations with positive findings for acute appendicitis were confirmed with surgical pathologic information. Sensitivity, specificity, negative predictive values, and positive predictive values were calculated. Receiver operating characteristic curves were generated, and area under the curve analysis was performed for each participating institution.

RESULTS

Of the cases that were evaluated, 9.3% (66/709) had MRI findings of acute appendicitis. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive values were 96.8%, 99.2%, 99.0%, 92.4%, and 99.7%, respectively. There was no statistically significant difference between centers that were included in the study (pair-wise probability values ranged from 0.12-0.99).

CONCLUSION

MRI is useful and reproducible in the diagnosis of suspected acute appendicitis during pregnancy.

Cost effectiveness of nonoperative management versus laparoscopic appendectomy for acute uncomplicated appendicitis

BACKGROUND

Appendectomy remains the gold standard in the treatment of acute, uncomplicated appendicitis in the United States. Nonetheless, there is growing evidence that nonoperative management is safe and efficacious.

METHODS

We constructed a decision tree to compare nonoperative management of appendicitis with laparoscopic appendectomy in otherwise healthy adults. Model variables were abstracted from a literature review, data from the Healthcare Cost and Utilization Project data, the Medicare Physician Fee schedule, and the American College of Surgeons Surgical Risk Calculator. Uncertainty surrounding parameters of the model was assessed via 1-way and probabilistic sensitivity analyses.

RESULTS

Operative management cost $12,213 per patient. Nonoperative management without interval appendectomy (IA) was the dominant strategy, costing $1,865 less and producing 0.03 more quality-adjusted life-years (QALYs). Nonoperative management with IA cost $4,271 more than operative management, but yielded only 0.01 additional QALY. One-way sensitivity analysis suggested operative management would become the preferred strategy if the recurrence rate was >40.5% or the total cost of appendectomy was decreased to <$5,468. Probabilistic sensitivity analysis confirmed nonoperative management without IA was the preferred strategy in 95.6% of cases.

CONCLUSION

Nonoperative management without IA is the least costly, most effective treatment for acute, uncomplicated appendicitis and warrants further evaluation in a disease thought to be definitively surgical.

Laparoscopic appendectomy and cholecystectomy versus open: a study in 1999 pregnant patients

BACKGROUND

When pregnant patients require surgery, whether to perform an operation open or laparoscopic is often debated. We evaluated the impact of laparoscopy for common general surgical problems in pregnancy to determine safety and trends in operative approach over time.

METHODS

Pregnant patients undergoing appendectomy or cholecystectomy were identified using the National Surgical Quality Improvement Program (NSQIP) database. We analyzed demographics, operative characteristics, and outcomes. Univariate comparison and multivariate regression analysis (MVA) were performed adjusting for confounding factors: age, body mass index (BMI), diabetes, and smoking, and an additional MVA was performed for perforated cases.

RESULTS

A total of 1999 pregnant patients between 2005 and 2012 were evaluated. Of 1335 appendectomies, 894 were performed laparoscopically (LA) and 441 open (OA). For 664 cholecystectomies, 606 were laparoscopic (LC) and 58 open (OC). There were no deaths. For LA versus OA, patient characteristics were not different {age: 27.7 vs. 28.2 years, p = 0.19; diabetes: 1.8 vs. 0.9%, p = 0.24; smoking: 19 vs. 16.1%, p = 0.2} except for BMI (27.9 vs. 28.4 kg/m(2); p = 0.03). LA had shorter operative times (ORT), length of stay (LOS), and fewer postoperative complications compared to OA. In MVA, difference between approaches remained statistically significant for ORT (<0.0001), LOS (<0.01), and wound complications (<0.01). MVA was performed for perforated cases alone: LA had equal ORT (p = 0.19) yet shorter LOS (p = <0.001). The majority of LA were performed in the last 4 years versus the first 4 years (61 vs. 39%, p < 0.001). For LC versus OC, patient characteristics were not different: age (28.3 vs. 28.7 years; p = 0.33), BMI (31.4 vs. 33.2 kg/m(2), p = 0.25), diabetes (2.8 vs. 3.5%, p = 0.68), and smoking (21.1 vs. 25.9%, p = 0.4). LC had a shorter ORT, LOS, and fewer postoperative complications than OC. In MVA, the difference between approaches remained statistically significant for ORT (<0.0001), LOS (<0.0001), and minor complications (<0.01). In MVA for cholecystitis with perforation, no difference was seen for LOS, ORT, or postoperative complications (p > 0.05). The percentage of LC cases appeared to increase over time (89 vs. 93%, p = 0.06).

CONCLUSION

While fetal events are unknown, LA and LC in pregnant patients demonstrated shorter ORT, LOS, and reduced complications and were performed more frequently over time. Even in perforated cases, laparoscopy appears safe in pregnant patients.

Evaluating Cost-effectiveness of Interventions That Affect Fertility and Childbearing: How Health Effects Are Measured Matters

BACKGROUND

Current guidelines for economic evaluations of health interventions define relevant outcomes as those accruing to individuals receiving interventions. Little consensus exists on counting health impacts on current and future fertility and childbearing. Our objective was to characterize current practices for counting such health outcomes.

METHODS

We developed a framework characterizing health interventions with direct and/or indirect effects on fertility and childbearing and how such outcomes are reported. We identified interventions spanning the framework and performed a targeted literature review for economic evaluations of these interventions. For each article, we characterized how the potential health outcomes from each intervention were considered, focusing on quality-adjusted life-years (QALYs) associated with fertility and childbearing.

RESULTS

We reviewed 108 studies, identifying 7 themes: 1) Studies were heterogeneous in reporting outcomes. 2) Studies often selected outcomes for inclusion that tend to bias toward finding the intervention to be cost-effective. 3) Studies often avoided the challenges of assigning QALYs for pregnancy and fertility by instead considering cost per intermediate outcome. 4) Even for the same intervention, studies took heterogeneous approaches to outcome evaluation. 5) Studies used multiple, competing rationales for whether and how to include fertility-related QALYs and whose QALYs to include. 6) Studies examining interventions with indirect effects on fertility typically ignored such QALYs. 7) Even recent studies had these shortcomings. Limitations include that the review was targeted rather than systematic.

CONCLUSIONS

Economic evaluations inconsistently consider QALYs from current and future fertility and childbearing in ways that frequently appear biased toward the interventions considered. As the Panel on Cost-Effectiveness in Health and Medicine updates its guidelines, making the practice of cost-effectiveness analysis more consistent is a priority. Our study contributes to harmonizing methods in this respect.

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 imaging of the gut: a primer for the luminal gastroenterologist

Magnetic resonance imaging (MRI) is well established for imaging the solid organs of the abdomen and pelvis. In recent years it has been having an increasingly important role in the evaluation of the gastrointestinal (GI) tract. Fluoroscopy and abdominal computed tomography, the traditional mainstays of bowel imaging, remain valuable; however, the contemporary emphasis on decreasing patient radiation exposure is driving practice toward non-ionizing modalities such as MRI. The inherent dynamic properties of MRI, its superior tissue contrast, and cross-sectional capabilities offer additional advantages. Here we review, from esophagus to anus, techniques and indications for MRI of the GI lumen with an emphasis on the normal MRI appearance of the GI tract and commonly encountered pathology.