The use of helical computed tomography in pregnancy for the diagnosis of acute appendicitis

Evaluation of Abdominal Emergencies

Early primary assessment and abdominal examination can often be enough to triage the patient with abdominal pain into those with less severe underlying pathologic condition from those with more acute findings. A focused history of the patient can then allow the clinician to develop their differential diagnosis. Once the differential diagnoses are determined, diagnostic imaging and laboratory findings can help confirm the diagnosis and allow for expeditious treatment and intervention.

Body mass index as an indicator of the likelihood of ultrasound visualization of the appendix in pregnant women with suspicion of appendicitis

PURPOSE

To determine if clinical characteristics of pregnant women are associated with the likelihood of ultrasound (US) visualization of the appendix in cases where there is a clinical suspicion of appendicitis.

MATERIALS AND METHODS

A retrospective study of 471 pregnant patients with suspicion of appendicitis from 2009 to 2018 were studied. Patients underwent sonography of the appendix as their initial imaging study. The association of body mass index (BMI) and gestational age with sonographic visualization of the appendix was analyzed using logistic regression. Cut-off values were determined for BMI to predict visualization of the appendix.

RESULTS

The rate of visualization of the appendix on US was 16% (95% CI 12% to 19%). When stratified by trimester of pregnancy, rebound pain on compression US examination in the 1st trimester and BMI in the 2nd and 3rd trimesters were identified as predictors of US visualization. Applying BMI cut-off values rounded to the nearest whole number, 36, 30, and 26 in the 1st, 2nd, and 3rd trimesters, non-visualization rates would be reduced by 16% (95% CI 10% to 25%), 35% (95% CI 29% to 42%), and 67% (95% CI 58% to 74%). Using BMI index cut-off values would reduce the number of primary US examinations by 35% (95% CI 30% to 39%) and increase the rate of visualization by 6% (95% CI 0.02% to 12%, P = 0.04).

CONCLUSION

Using BMI cut-off values for determining the efficaciousness of US visualization of the appendix in pregnant women with suspicion of appendicitis could significantly reduce the non-visualization rate.

Computed tomography for diagnosis of acute appendicitis in adults

BACKGROUND

Diagnosing acute appendicitis (appendicitis) based on clinical evaluation, blood testing, and urinalysis can be difficult. Therefore, in persons with suspected appendicitis, abdominopelvic computed tomography (CT) is often used as an add-on test following the initial evaluation to reduce remaining diagnostic uncertainty. The aim of using CT is to assist the clinician in discriminating between persons who need surgery with appendicectomy and persons who do not.

OBJECTIVES

Primary objective Our primary objective was to evaluate the accuracy of CT for diagnosing appendicitis in adults with suspected appendicitis. Secondary objectives Our secondary objectives were to compare the accuracy of contrast-enhanced versus non-contrast-enhanced CT, to compare the accuracy of low-dose versus standard-dose CT, and to explore the influence of CT-scanner generation, radiologist experience, degree of clinical suspicion of appendicitis, and aspects of methodological quality on diagnostic accuracy.

SEARCH METHODS

We searched MEDLINE, Embase, and Science Citation Index until 16 June 2017. We also searched references lists. We did not exclude studies on the basis of language or publication status.

SELECTION CRITERIA

We included prospective studies that compared results of CT versus outcomes of a reference standard in adults (> 14 years of age) with suspected appendicitis. We excluded studies recruiting only pregnant women; studies in persons with abdominal pain at any location and with no particular suspicion of appendicitis; studies in which all participants had undergone ultrasonography (US) before CT and the decision to perform CT depended on the US outcome; studies using a case-control design; studies with fewer than 10 participants; and studies that did not report the numbers of true-positives, false-positives, false-negatives, and true-negatives. Two review authors independently screened and selected studies for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently collected the data from each study and evaluated methodological quality according to the Quality Assessment of Studies of Diagnostic Accuracy - Revised (QUADAS-2) tool. We used the bivariate random-effects model to obtain summary estimates of sensitivity and specificity.

MAIN RESULTS

We identified 64 studies including 71 separate study populations with a total of 10,280 participants (4583 with and 5697 without acute appendicitis). Estimates of sensitivity ranged from 0.72 to 1.0 and estimates of specificity ranged from 0.5 to 1.0 across the 71 study populations. Summary sensitivity was 0.95 (95% confidence interval (CI) 0.93 to 0.96), and summary specificity was 0.94 (95% CI 0.92 to 0.95). At the median prevalence of appendicitis (0.43), the probability of having appendicitis following a positive CT result was 0.92 (95% CI 0.90 to 0.94), and the probability of having appendicitis following a negative CT result was 0.04 (95% CI 0.03 to 0.05). In subgroup analyses according to contrast enhancement, summary sensitivity was higher for CT with intravenous contrast (0.96, 95% CI 0.92 to 0.98), CT with rectal contrast (0.97, 95% CI 0.93 to 0.99), and CT with intravenous and oral contrast enhancement (0.96, 95% CI 0.93 to 0.98) than for unenhanced CT (0.91, 95% CI 0.87 to 0.93). Summary sensitivity of CT with oral contrast enhancement (0.89, 95% CI 0.81 to 0.94) and unenhanced CT was similar. Results show practically no differences in summary specificity, which varied from 0.93 (95% CI 0.90 to 0.95) to 0.95 (95% CI 0.90 to 0.98) between subgroups. Summary sensitivity for low-dose CT (0.94, 95% 0.90 to 0.97) was similar to summary sensitivity for standard-dose or unspecified-dose CT (0.95, 95% 0.93 to 0.96); summary specificity did not differ between low-dose and standard-dose or unspecified-dose CT. No studies had high methodological quality as evaluated by the QUADAS-2 tool. Major methodological problems were poor reference standards and partial verification primarily due to inadequate and incomplete follow-up in persons who did not have surgery.

AUTHORS' CONCLUSIONS

The sensitivity and specificity of CT for diagnosing appendicitis in adults are high. Unenhanced standard-dose CT appears to have lower sensitivity than standard-dose CT with intravenous, rectal, or oral and intravenous contrast enhancement. Use of different types of contrast enhancement or no enhancement does not appear to affect specificity. Differences in sensitivity and specificity between low-dose and standard-dose CT appear to be negligible. The results of this review should be interpreted with caution for two reasons. First, these results are based on studies of low methodological quality. Second, the comparisons between types of contrast enhancement and radiation dose may be unreliable because they are based on indirect comparisons that may be confounded by other factors.

Accuracy of ultrasonography in diagnosing acute appendicitis during pregnancy based on surgical findings

Background: Acute appendicitis is the most common nonobstetric surgical problem in pregnancy. Common signs and symptoms of appendicitis are less reliable during pregnancy due to physiological changes; thus, the role of imaging becomes prominent. Thus, in the present study, we aimed at assessing the accuracy of sonography in diagnosing acute appendicitis during pregnancy. Methods: In this prospective analytic study, among 1000 patients diagnosed and treated as acute appendicitis, clinical and sonographic findings of 58 consecutive pregnant patients, who underwent appendectomy, were recorded and analyzed. All surgically resected samples were evaluated and confirmed through histological evaluation. Sonographic criteria were utilized to judge the results for appendicitis. Diagnostic test performance characteristics (sensitivity, specificity, predictive values, and likelihood ratios) were calculated. Results: The mean age of the patients was 27.1±4.9 years, and the most common clinical symptom was right lower quadrant pain. There was no significant difference in the mean leukocyte count between the appendicitis group and normal appendix group (p=0.768). Left shift was also unrelated with the appendix pathology (p= 0.549). The sensitivity, specificity, predictive values (positive and negative), and likelihood ratios (positive and negative) were 80%, 75%, 91.4%, 52.9%, 3.2, and 0.26, respectively during all trimesters of pregnancy. Conclusion: Ultrasonography is the initially preferred imaging modality in pregnant women suspected of having acute appendicitis with an acceptable sensitivity; however, application of other imaging modalities such as CT scan or MRI is recommended after inconclusive ultrasonography results.

Emergency general surgery in pregnancy

It is often that the acute care surgeon will be called on to evaluate the pregnant patient with abdominal pain. Most of the diagnostic and management decisions regarding pregnant patients will follow the usual tenets of surgery; however, there are important differences in the pregnant patient to be aware of to avoid pitfalls which can lead to complications for both mother and fetus. This review hopes to describe the most common emergencies facing the surgeon caring for the pregnant patient and the latest management options.

Computed tomography and patient risk: Facts, perceptions and uncertainties

Since its introduction in the 1970s, computed tomography (CT) has revolutionized diagnostic decision-making. One of the major concerns associated with the widespread use of CT is the associated increased radiation exposure incurred by patients. The link between ionizing radiation and the subsequent development of neoplasia has been largely based on extrapolating data from studies of survivors of the atomic bombs dropped in Japan in 1945 and on assessments of the increased relative risk of neoplasia in those occupationally exposed to radiation within the nuclear industry. However, the association between exposure to low-dose radiation from diagnostic imaging examinations and oncogenesis remains unclear. With improved technology, significant advances have already been achieved with regards to radiation dose reduction. There are several dose optimization strategies available that may be readily employed including omitting unnecessary images at the ends of acquired series, minimizing the number of phases acquired, and the use of automated exposure control as opposed to fixed tube current techniques. In addition, new image reconstruction techniques that reduce radiation dose have been developed in recent years with promising results. These techniques use iterative reconstruction algorithms to attain diagnostic quality images with reduced image noise at lower radiation doses.

Acute appendicitis in pregnancy: literature review

INTRODUCTION

suspected appendicitis is the most common indication for surgery in non-obstetric conditions during pregnancy and occurs in about one in 500 to one in 635 pregnancies per year. This occurs more often in the second trimester of pregnancy. Acute appendicitis is the most common general surgical problem encountered during pregnancy.

METHODS

a literature review on research of scientific articles, under the terms "acute appendicitis" and "pregnancy", in PubMed, Lilacs/SciELO, Scopus, Cochrane Library and Uptodate databases.

RESULTS

the clinical manifestations of appendicitis are similar to non-pregnant women, however, without a classic presentation, which often occurs, diagnosis is difficult and must be supported by imaging.

DISCUSSION

clinical diagnosis should be strongly suspected in pregnant women with classic findings such as abdominal pain that migrates to the right lower quadrant. The main purpose of imaging is to reduce delays in surgical intervention due to diagnostic uncertainty. A secondary objective is to reduce, but not eliminate, the negative appendectomy rate. Differential diagnosis of suspected acute appendicitis usually includes pathologies considered in non-pregnant people.

CONCLUSION

the imaging study of choice is ultrasound, MRI may be used when the former is not conclusive and, as a last resort, a CT scan can be performed. The treatment remains appendectomy by laparotomy, since the feasibility of video- assisted surgery in these cases remains controversial.

Challenges in magnetic resonance imaging for suspected acute appendicitis in pregnant patients

The assessment of a gravid patient with abdominal pain is a clinical challenge, as one must consider not only the common etiologies for abdominal pain but also etiologies resulting from the pregnancy. Further complicating the assessment is the altered anatomy and physiology that result from the enlarged uterus displacing and compressing normal anatomical structures. This alteration of anatomy makes the symptoms of appendicitis more variable and thus the diagnosis more difficult. Appropriate and timely imaging can result in better patient outcomes, and when appendicitis is suspected, imaging investigation should not be delayed. This article reviews some of the challenges of magnetic resonance imaging in gravid patients with suspected appendicitis and presents strategies for imaging this population.

Management of pregnant patients undergoing general surgical procedures

Pregnant patients have a 0.2% to 0.75% chance of developing a medical condition that requires a general surgical intervention during pregnancy. To safely and appropriately care for patients, surgeons must be cognizant of the maternal physiologic changes in pregnancy as well as of the unique risk to both mothers and fetuses of diagnostic modalities, anesthetic care, operative intervention, and postoperative management. Surgeons can be assured that, if these risks are understood and considered, operating during pregnancy, even in the abdomen, can be safely undertaken.

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

OBJECTIVE

To assess the cost-effectiveness of diagnostic laparoscopy, computed tomography (CT), and magnetic resonance imaging (MRI) after indeterminate ultrasonography in pregnant women with suspected appendicitis.

METHODS

A decision-analytic model was developed to simulate appendicitis during pregnancy taking into consideration the health outcomes for both the pregnant women and developing fetuses. Strategies included diagnostic laparoscopy, CT, and MRI. Outcomes included positive appendectomy, negative appendectomy, maternal perioperative complications, preterm delivery, fetal loss, childhood cancer, lifetime costs, discounted life expectancy, and incremental cost-effectiveness ratios.

RESULTS

Magnetic resonance imaging is the most cost-effective strategy, costing $6,767 per quality-adjusted life-year gained relative to CT, well below the generally accepted $50,000 per quality-adjusted life-year threshold. In a setting where MRI is unavailable, CT is cost-effective even when considering the increased risk of radiation-associated childhood cancer ($560 per quality-adjusted life-year gained relative to diagnostic laparoscopy). Unless the negative appendectomy rate is less than 1%, imaging of any type is more cost-effective than proceeding directly to diagnostic laparoscopy.

CONCLUSIONS

Depending on imaging costs and resource availability, both CT and MRI are potentially cost-effective. The risk of radiation-associated childhood cancer from CT has little effect on population-level outcomes or cost-effectiveness but is a concern for individual patients. For pregnant women with suspected appendicitis, an extremely high level of clinical diagnostic certainty must be reached before proceeding to operation without preoperative imaging.

APPENDICITIS IN PREGNANCY

Acute appendicitis is the most common non-obstetric indication for surgical intervention in pregnancy, complicating 1/500 to 1/2000 deliveries. Due to the anatomical and physiological changes associated with pregnancy, appendicitis may present a diagnostic dilemma, leading to management delays and thus increasing the risk of appendiceal perforation. Many of the common presenting symptoms of appendicitis are common features of normal pregnancy including lower abdominal pain, nausea, vomiting and leukocytosis. Furthermore, the enlarging gravid uterus may displace the appendix to varying degrees thus altering the classic symptom pattern of appendicitis. The often nonspecific presentation in pregnancy may necessitate the utilization of diagnostic imaging to aid in accurate diagnosis. However, the perforated appendix is the most common surgical cause of fetal loss and the time required for any diagnostic aid must be weighed against the increasing risk of perforation caused by delay in surgical intervention.

Appendicitis During Pregnancy

Acute appendicitis is the most common extra-uterine surgical emergency requiring immediate surgical intervention during pregnancy [1]. Six young female patients presented with appendicitis during May 1996 to May 2001 in different service hospitals. Five patients underwent emergency appendectomy successfully. Gestational age at presentation included first trimester in 4 patients, second trimester in 2 patients and none in third trimester. 84% had pathologically proven acute appendicitis. One patient presented with appendicular lump in first trimester, proved on ultra sonography examination, which was treated by Oshner Sherren regime and subsequently interval appendectomy was done in second trimester. No long term adverse maternal morbidity or mortality was reported. One patient had premature onset of labour and delivered. Natural history of acute appendicitis is not changed during pregnancy while gestational physiological changes obscure the accurate diagnosis of acute appendicitis.

Gastrointestinal Conditions during Pregnancy

Pregnancy causes anatomic and physiologic changes in the gastrointestinal tract. Pregnant women with intestinal disease such as Crohn disease or ulcerative colitis pose a management challenge in clinical diagnosis, radiologic evaluation, and treatment secondary to potential risk to the fetus. Heightened physician awareness on possible etiologies such as appendicitis, diverticulitis, and rarely colorectal cancer is required for rapid diagnosis and treatment to improve maternal/fetal outcome. A multidisciplinary approach to evaluation is a necessity because radiologic procedures and treatment medications commonly used in nonpregnant patients may have a potential harmful effect on the fetus. The authors review several gastrointestinal conditions encountered during pregnancy and address presentation, diagnosis, and treatment of each condition.

Diagnosis of appendicitis in pregnancy

BACKGROUND

The diagnosis of appendicitis in pregnant patients is challenging.

METHODS

The records of pregnant patients with suspected appendicitis were reviewed.

RESULTS

Forty-seven patients with suspected appendicitis were identified. Twenty-four patients did not undergo surgery. Twenty-three patients had ultrasound (US), none of which visualized the appendix. Seventeen patients were followed up clinically and improved. Six patients had a negative computed tomography (CT) and none required surgery. Twenty-three patients underwent surgery for presumed appendicitis. Three patients had no imaging. Twelve patients had US only; US was positive in 5 patients and all had appendicitis. Seven patients who underwent surgery had a nondiagnostic US. One patient had appendicitis. Seven patients had a positive CT and appendicitis at surgery. One patient had a positive US and magnetic resonance imaging, and had appendicitis. A total of 43 patients had US, of which 86% were nondiagnostic. Six US were read as positive and all patients had appendicitis. Thirteen patients had CT with no false-positive or false-negative results.

CONCLUSIONS

US, when read as positive, requires no further confirmatory test other than surgery. If US is nondiagnostic, further imaging may avoid a negative appendectomy.

The development, validation and application of a multi-detector CT (MDCT) scanner model for assessing organ doses to the pregnant patient and the fetus using Monte Carlo simulations

The latest multiple-detector technologies have further increased the popularity of x-ray CT as a diagnostic imaging modality. There is a continuing need to assess the potential radiation risk associated with such rapidly evolving multi-detector CT (MDCT) modalities and scanning protocols. This need can be met by the use of CT source models that are integrated with patient computational phantoms for organ dose calculations. Based on this purpose, this work developed and validated an MDCT scanner using the Monte Carlo method, and meanwhile the pregnant patient phantoms were integrated into the MDCT scanner model for assessment of the dose to the fetus as well as doses to the organs or tissues of the pregnant patient phantom. A Monte Carlo code, MCNPX, was used to simulate the x-ray source including the energy spectrum, filter and scan trajectory. Detailed CT scanner components were specified using an iterative trial-and-error procedure for a GE LightSpeed CT scanner. The scanner model was validated by comparing simulated results against measured CTDI values and dose profiles reported in the literature. The source movement along the helical trajectory was simulated using the pitch of 0.9375 and 1.375, respectively. The validated scanner model was then integrated with phantoms of a pregnant patient in three different gestational periods to calculate organ doses. It was found that the dose to the fetus of the 3 month pregnant patient phantom was 0.13 mGy/100 mAs and 0.57 mGy/100 mAs from the chest and kidney scan, respectively. For the chest scan of the 6 month patient phantom and the 9 month patient phantom, the fetal doses were 0.21 mGy/100 mAs and 0.26 mGy/100 mAs, respectively. The paper also discusses how these fetal dose values can be used to evaluate imaging procedures and to assess risk using recommendations of the report from AAPM Task Group 36. This work demonstrates the ability of modeling and validating an MDCT scanner by the Monte Carlo method, as well as assessing fetal and organ doses by combining the MDCT scanner model and the pregnant patient phantom.

CT evaluation of placental abruption in pregnant trauma patients

The purpose of the study was to assess the possibility of placental injury detection on computed tomography (CT) in pregnant trauma patients. The images and dictated reports of 44 CT scans of pregnant women who presented to the University of California Irvine Medical Center (UCIMC) from 2003 to 2008 for traumatic abdominal conditions were reviewed for placental abruption. Performances of original dictated reports, an untrained reviewer, and a trained reviewer (who was trained on 22 non-traumatic scans) were compared. Of the 66 pregnant women who received abdominal CT scans, 44 sustained abdominal trauma. Seven suffered placental abruptions, all of which were identified on CT. Sensitivity and specificity were 100% and 79.5%, respectively, for the untrained reviewer, 100% and 82.1% for the trained reviewer, and 42.9% and 89.7% for the original dictated reports. Placental abruptions are often overlooked on CT scan. Sensitivity may be improved by systematic evaluation of the placenta and specificity by training on normal placental morphology.

Strategies for reducing radiation dose in CT

In recent years, the media has focused on the potential danger of radiation exposure from CT, even though the potential benefit of a medically indicated CT far outweighs the potential risks. This attention has reminded the radiology community that doses must be as low as reasonably achievable (ALARA) while maintaining diagnostic image quality. To satisfy the ALARA principle, the dose reduction strategies described in this article must be well understood and properly used. The use of CT must also be justified for the specific diagnostic task.

Guidelines for computed tomography and magnetic resonance imaging use during pregnancy and lactation

There has been a substantial increase in the use of computed tomography (CT) and magnetic resonance imaging (MRI) in pregnancy and lactation. Among some physicians and patients, however, there are misperceptions regarding risks, safety, and appropriate use of these modalities in pregnancy. We have developed a set of evidence-based guidelines for the use of CT, MRI, and contrast media during pregnancy for selected indications including suspected acute appendicitis, pulmonary embolism, renal colic, trauma, and cephalopelvic disproportion. Ultrasonography is the initial modality of choice for suspected appendicitis, but if the ultrasound examination is negative, MRI or CT can be obtained. Computed tomography should be the initial diagnostic imaging modality for suspected pulmonary embolism. Ultrasonography should be the initial study of choice for suspected renal colic. Ultrasonography can be the initial imaging evaluation for trauma, but CT should be performed if serious injury is suspected. Pelvimetry now is used rarely for suspected cephalopelvic disproportion, but when required, low-dose CT pelvimetry can be performed with minimal risk. Although iodinated contrast seems safe to use in pregnancy, intravenous gadolinium is contraindicated and should be used only when absolutely essential. It seems to be safe to continue breast-feeding immediately after receiving iodinated contrast or gadolinium. Although teratogenesis is not a major concern after exposure to prenatal diagnostic radiation, carcinogenesis is a potential risk. When used appropriately, CT and MRI can be valuable tools in imaging pregnant and lactating women; risks and benefits always should be considered and discussed with patients.

Emergency department imaging: current practice

PURPOSE

To provide a snapshot of the demographics of radiologists providing coverage for emergency departments (EDs) and current imaging practices in EDs in the United States.

METHODS

An online survey was created with Views Flash 3 software (Cogix, Monterey, California). Random e-mail addresses from a variety of databases were chosen. A total of 678 surveys were sent over a 9-month period.

RESULTS

One hundred ninety-two radiology groups (28%) responded to the survey. Forty-one groups (21%) had designated emergency radiology divisions. Sixty-three groups (33%) were using computed tomographic (CT) coronary angiography in the ED workup of chest-pain. Thirty-five groups (18%) were using "triple-rule-out scans" (ie, a single CT scan to rule out coronary artery disease, pulmonary embolism, and aortic dissection). Multiplanar reconstructions of chest, abdominal, and pelvic CT images were routinely performed by 95 groups (49%). Forty-four percent used reformatted CT images instead of conventional radiographs in the workup of cervical spine trauma, and 68 groups (35%) used reformations in thoracic and lumbar spine trauma. Ninety groups (47%) did not use oral contrast for blunt abdominal trauma CT scanning. Sixty-seven respondents (35%) preferred computed tomography to evaluate for acute appendicitis in the setting of pregnancy. Forty percent of imaging equipment located within the EDs was CT scanners. The majority of the groups still communicated unexpected findings via telephone (49%).

CONCLUSION

New imaging practices for the evaluation of entities such as chest pain, spine trauma, and abdominal pain and trauma are emerging in EDs. As one plans ED development, these trends should be considered.

Appendectomy during pregnancy in sickle cell disease patients

BACKGROUND/AIM

Acute appendicitis during pregnancy is the most common problem encountered in general surgery. However, limited data are available regarding acute appendicitis in pregnant sickle cell disease (SCD) patients. We aimed to study was the clinical presentation, management, and outcome in SCD patients who underwent appendectomy for suspected acute appendicitis during pregnancy.

MATERIALS AND METHODS

Between January 1998 and December 2006, 65 pregnant patients with clinically suspected appendicitis underwent surgery at our hospital of whom 11 were SCD patients. Data collected retrospectively included age, gestational stage, clinical signs and symptoms, operative findings, and complications.

RESULTS

Eleven out of 65 (16.9%) were SCD patients. The mean age in the SCD group was 22.5 years while the mean gravida and parity values were 2.0 and 1.1, respectively. The mean HbS, HbF, and HbA2 values were 71.1, 26.2, and 2.6%, respectively. Abdominal pain and vomiting were the most common presenting symptoms regardless of the gestational age. Abdominal and rebound tenderness were the most common physical signs. The mean operative time was 49 min (range: 35-125 min) and the average length of postoperative hospital stay was 4.7 days (2-8 days). There was no maternal death but one patient had spontaneous abortion during the first trimester, two days after the operation. Two patients had premature, postoperative delivery at 30 and 31 weeks of gestation.

CONCLUSION

The clinical manifestations and diagnosis of appendicitis in sickler pregnant patients are similar to those in nonsickler pregnant patients.

Imaging the pregnant patient for nonobstetric conditions: algorithms and radiation dose considerations

Use of diagnostic imaging studies for evaluation of pregnant patients with medical conditions not related to pregnancy poses a persistent and recurring dilemma. Although a theoretical risk of carcinogenesis exists, there are no known risks for development of congenital malformations or mental retardation in a fetus exposed to ionizing radiation at the levels typically used for diagnostic imaging. An understanding of the effects of ionizing radiation on the fetus at different gestational stages and the estimated exposure dose received by the fetus from various imaging modalities facilitates appropriate choices for diagnostic imaging of pregnant patients with nonobstetric conditions. Other aspects of imaging besides radiation (ie, contrast agents) also carry potential for fetal injury and must be taken into consideration. Imaging algorithms based on a review of the current literature have been developed for specific nonobstetric conditions: pulmonary embolism, acute appendicitis, urolithiasis, biliary disease, and trauma. Imaging modalities that do not use ionizing radiation (ie, ultrasonography and magnetic resonance imaging) are preferred for pregnant patients. If ionizing radiation is used, one must adhere to the principle of using a dose that is as low as reasonably achievable after a discussion of risks versus benefits with the patient.

Imaging of gastrointestinal and hepatic diseases during pregnancy

Imaging of the abdomen for suspected gastrointestinal and hepatic disease during pregnancy is assuming greater importance. Like clinical evaluation, imaging of the abdomen and pelvis is challenging but is vitally important to prevent delayed diagnosis or unnecessary interventions. Also choice of imaging modality is influenced by factors which could impact on fetal safety such as the use of ionising radiation and magnetic resonance imaging. This article discusses important issues in imaging of gastrointestinal and hepatic disease in pregnancy and the puerperium.

Cecal volvulus in pregnancy: report of a case and review of the safety and utility of medical diagnostic imaging in the assessment of the acute abdomen during pregnancy

We report a case of a 38-year-old woman who presents at 31 weeks of gestation with acute abdominal pain. Computed tomography (CT) scan of the abdomen and pelvis showed a cecal volvulus. Emergency cesarean section was performed for fetal distress. Laparotomy confirmed the CT findings and a right hemicolectomy was performed. While not advocating overutilization, this case demonstrates that helical CT can be, in the correct clinical scenario, an acceptable, useful, and relatively noninvasive test in the accurate assessment of the acute abdomen in pregnancy. We review the safety and utility of medical diagnostic imaging in the assessment of the acute abdomen in pregnancy.

Twin pregnancy complicated with acute appendicitis and cholecystitis in the same gestational period

INTRODUCTION

Acute appendicitis and symptomatic biliary stones are the most common indications for non-obstetrical surgical procedures during pregnancy. However, combination of these two clinical presentations in the same gestational period is anecdotal.

CASE REPORT

A 30-year-old twin pregnant patient complicated with acute appendicitis followed by cholecystitis was reported with poor fetal outcomes.

CONCLUSION

Despite appropriate management when two conditions, appendicitis and cholecystitis, occur in the same gestational period one after another complications might become inevitable.

Diagnosis and management of diverticulitis and appendicitis

Diverticulitis and appendicitis are common infections of the gastrointestinal tract that require urgent medical and surgical attention. Successful management of these conditions requires a multidisciplinary approach among primary care providers, gastroenterologists, surgeons, and radiologists. The diagnosis of appendicitis, in particular, can be difficult. Advances in radiographic imaging have improved the diagnostic accuracy in these infections. Minimally invasive surgical techniques have improved the patient's postoperative recovery when surgery is necessary in the management of these conditions.

Radiation Dose to the Fetus from Body MDCT During Early Gestation

OBJECTIVE

The purpose of our study was to determine radiation dose to the fetus at early gestation when contemporary MDCT scanners are used for common clinical indications.

MATERIALS AND METHODS

Anthropomorphic phantoms were constructed to reflect a pregnant woman. Thermoluminescence dosimeters (TLDs) and metal oxide semiconductor field effect transistor (MOSFET) detectors were placed in appropriate locations to determine real-time radiation exposure to the fetus at 0 and 3 months' gestation. Imaging was performed on a 16-MDCT scanner using current institutional CT protocols: renal stone (140 kVp, 160 mA, rotation time of 0.5 sec, 16 x 0.625 mm), appendix (140 kVp, 340 mA, rotation time of 0.5 sec, 16 x 0.625 mm), and pulmonary embolus (140 kVp, 380 mA, rotation time of 0.8 sec, 16 x 1.25 mm).

RESULTS

The radiation dose to the fetus at 0 and 3 months, respectively, was as follows: renal stone protocol, 0.8-1.2 and 0.4-0.7 cGy; appendix protocol, 1.52-1.68 and 2-4 cGy; and pulmonary embolus protocol, 0.024-0.047 and 0.061-0.066 cGy.

CONCLUSION

Radiation doses to the fetus from institutional MDCT protocols that may be used during pregnancy (for pulmonary embolus, appendicitis, and renal colic) are below the level thought to induce neurologic detriment to the fetus. Imaging the mother for appendicitis theoretically may double the fetal risk for developing a childhood cancer. Radiation doses to the fetus from pulmonary embolus chest CT angiography are of the same magnitude as ventilation-perfusion (V/Q) scanning.

Exames radiológicos na gestação

Gestantes podem precisar ser submetidas a exames radiológicos para um diagnóstico preciso e conduta correta. Nestes casos a exposição à radiação ionizante e seus efeitos sobre o feto são motivo de preocupação para a paciente e o seu médico. Na verdade, a maioria destes exames é segura e não oferece risco significativo ao feto. No entanto, é importante que o radiologista conheça estes riscos potenciais para poder orientar adequadamente todos os envolvidos no atendimento.

The use of radiographic modalities to diagnose infection in pregnancy

The usefulness of sonography, plain film, CT, and MRI in diagnosing infections in pregnancy is discussed. Imaging modality choices for specific clinical indications in pregnancy are reviewed. The overall safety of most techniques in pregnancy is emphasized.

Right-Lower-Quadrant Pain and Suspected Appendicitis in Pregnant Women: Evaluation with MR Imaging—Initial Experience

PURPOSE

To determine if there is a role for magnetic resonance (MR) imaging in evaluation of pregnant women with acute right-lower-quadrant pain in whom acute appendicitis is suspected.

MATERIALS AND METHODS

Informed consent and institutional review board approval were obtained. Images obtained with a 1.5-T MR imager and medical records of 23 pregnant women (age range, 19-34 years; mean age, 24.7 years) who presented with acute right-lower-quadrant pain were retrospectively reviewed. MR protocol included use of transverse, coronal, and sagittal noncontiguous T2-weighted single-shot fast spin-echo (SE) sequences; transverse fat-suppressed T2-weighted fast SE sequences; transverse T1-weighted gradient-recalled-echo sequences; and transverse and coronal short inversion time inversion-recovery sequences performed through the lower abdomen and pelvis. MR findings were evaluated by two radiologists and compared with surgical and pathologic findings and clinical follow-up data.

RESULTS

Appendix was detected in 20 (86.9%) of 23 patients. Seven patients underwent surgery; four had acute appendicitis, and three had ovarian torsion. Two patients with pelvic abscesses not related to appendicitis underwent percutaneous drainage. Fourteen patients were treated medically. Dilated thick-walled appendix and periappendiceal inflammation were detected in three (75%) of four patients with acute appendicitis. In one patient with appendicitis, the appendix could not be visualized, but inflammation was present in the right lower quadrant. In three patients with ovarian torsion, MR imaging demonstrated right adnexal mass or inflammation. MR imaging was used to correctly identify pelvic abscesses and healthy appendix in two patients. A healthy appendix was depicted in 17 (89.5%) of 19 patients without acute appendicitis.

CONCLUSION

MR imaging shows promise for evaluation of pregnant women in whom acute appendicitis is suspected by enabling diagnosis of other possible causes of right-lower-quadrant pain, including ovarian torsion or pelvic abscesses, and demonstrating a healthy or unhealthy appendix.

MRI for clinically suspected appendicitis during pregnancy

OBJECTIVE

The purpose of this study was to evaluate whether MRI can be used to accurately diagnose or exclude appendicitis in pregnant patients with clinically suspected appendicitis.

CONCLUSION

Our results suggest that MRI is helpful in the examination and diagnosis of acute appendicitis in pregnant patients. MRI may therefore be a good alternative to CT in pregnant patients for whom sonographic findings are nondiagnostic.

Ninety-four appendectomies for suspected acute appendicitis during pregnancy

Acute appendicitis during pregnancy is a rare event, and large numbers of cases reported in the literature stem entirely from data stored in national registers. Between 1974 and 2000 relevant perioperative data on the treatment of appendicitis were collected consecutively and analyzed retrospectively. Surgical and obstetric data relating to the medical history, the clinical, intraoperative, and histologic findings, and the course of the pregnancy were recorded. Altogether, 9793 appendectomies were performed, 94 of which were in pregnant women (24.5% during the first trimester, 51% during the second trimester, and 24.5% during the third trimester). This represents 0.2% of the 46,960 deliveries during the period under observation. Fifty percent of the case histories during the second trimester were atypical. The overall perforation rate was 14.9%; it was 8.7%, 12.5%, and 26.1% during the three trimesters, respectively. Maternal mortality was 0%; the combined miscarriage/abortion rate was 8.5% (n = 8); and infant mortality was 3.2% (n = 3). The postoperative spontaneous abortion rate was 13.0% and the additional therapeutic/requested abortion rate 21.7% during the first trimester. In view of the elevated postoperative abortion rate and the facility of the clinical diagnosis during the first trimester, the indication for invasive diagnostic measures and surgery requires careful consideration. During the second and third trimesters the difficulty of establishing a clinical diagnosis makes it necessary to undertake exploratory surgery early.

Management of general surgical problems in the pregnant patient

BACKGROUND

General surgeons are frequently consulted for nonobstetrical surgical problems in pregnant women, as up to 2% of pregnancies are complicated by such problems. Concerns over the increased morbidity for both the pregnant patient and the fetus are unique to this population.

DATA SOURCES

A review of the English language literature surrounding nonobstetrical surgical issues was collected through a Medline search and review of relevant society and academy papers.

CONCLUSIONS

This manuscript offers a review of current information regarding aspects of surgical care in the pregnant patient. Areas discussed include anesthesiology, radiology, laparoscopy, and specific common and uncommon surgical diseases found in the pregnant patient.

Nontraumatic abdominal surgical emergencies in the pregnant patient

Although most EPs are aware of the diverse presentations of ectopic pregnancy, this diagnosis remains a formidable challenge in the ED. The diagnosis of abdominal surgical emergencies in pregnant patients continues to challenge EPs, surgeons, and obstetricians alike. Understanding how the gravid state can obscure common conditions such as appendicitis, cholecystitis. bowel obstruction, and adnexal torsion might help the EP identify suspicious cases early, preventing serious consequences to the mother and fetus.

Laparoscopy for appendicitis and cholelithiasis during pregnancy: a new standard of care

BACKGROUND

Subsequent to a report from the authors' institution, the laparoscopic management of symptomatic cholelithiasis and appendicitis during pregnancy has become the standard of care at LDS Hospital using institutional guidelines. For comparison with previous outcomes described by the authors, 59 additional laparoscopic cases are reported.

METHODS

Medical records of all pregnant patients at LDS Hospital who underwent open or laparoscopic cholecystectomy or appendectomy between 1998 and 2002 were reviewed. The outcomes were compared with the authors' previous data.

RESULTS

The laparoscopic management of symptomatic cholelithiasis and appendicitis during pregnancy increased from 54% to 97%. No significant differences in preterm delivery rates, birth weights, or 5-min Apgar scores were found between the two periods. No birth defects or uterine injuries occurred.

CONCLUSIONS

With the use of the authors' guidelines, laparoscopy has become the standard of care for managing symptomatic cholelithiasis and appendicitis during pregnancy at LDS Hospital without significant increase in morbidity or mortality.