Endovaginal sonographic evaluation of ectopic pregnancy: a prospective study

Correlation of sonographic with intraoperative findings in laparoscopic managed ectopic pregnancies, a 10-year synopsis: a restrospective observational study

BACKGROUND

Ectopic pregnancies (EP) are a common pregnancy complication that's associated with significant morbidity and rarely mortality if not managed properly. Ultrasound examination forms the cornerstone of diagnosis of EP with some sonographic features occasionally not correlating with intraoperative findings. We set out to conduct an audit of EP managed surgically at our hospital for a 10-year period and discern the correlation and prediction of sonographic findings to intraoperative findings.

METHODS

This study was designed as a Retrospective Observational Study based at the Aga Khan University Hospital (AKUH). Study population was all women admitted to AKUH with a diagnosis of ectopic pregnancy that was surgically managed between the period of January 1st 2011 to December 31st 2020. Analysis of data was done against a pre-set checklist. Descriptive statistics for continuous variables was calculated and tabulated in graphs and tables. SPSS version 22 was used for analysis of data.

RESULTS

A total of 337 patients in this study had ultrasound findings. 99.7% (n = 336) of these patients had an intraoperatively confirmed EP. The commonest ultrasound finding was an adnexal mass in 97.1% (n = 309) of patients. These were confirmed surgically in 290 patients at the following locations: 76.6% (n = 222) were ampullary in location; 10.7% (n = 31) were fimbrial in location; 8.6%(n = 25) were isthmic in location; 2.4%(n = 7) were interstitial in location; 1%(n = 3) were abdominal in location; while 0.3% were located in the ovary(n = 1) or round ligament(n = 1) each. Interstitial EP on ultrasound were all (100%) confirmed in the same location intraoperatively, with ampullary EP also correlating fairly well with intraoperative location (75%). The distribution of location in the minor hemoperitoneum (HP) versus major HP groups were similar except for interstitial EP that increased from 1.4% in the minor HP group to 9.5% in the major HP group.

CONCLUSION

In conclusion, ultrasonography still represents the best imaging modality for EP. The most common finding is usually an adnexal mass with no specific location. Most (99.7%) of the patients with this sonographic finding usually have a confirmed EP. Interstitial EP are the most well localized with ultrasound followed by ampullary EP. Furthermore, the presence of major (> 500mls) hemoperitoneum may act as an adjunct for diagnosis of an interstitial EP.

Ovarian Pregnancy

Ovarian pregnancy is a rare uncommon presentation of an ectopic pregnancy. Without any known risk factors, ovarian pregnancy seems to appear at random. A 29-year-old female patient with previous two cesarean deliveries visited the gynecology emergency department with the complaint of constant dull aching pain in the lower abdomen, aggravated by postural changes. Per vaginal examination, cervical motion tenderness was present. The patient was admitted, and her transvaginal sonography was done along with a urine pregnancy kit test for the suspicion of ectopic gestation. After the initial treatment and arrangement of two units of packed red blood cells after proper grouping and cross-matching for the patient, laparotomy was done. At the time of surgery, left-sided ruptured ovarian pregnancy was confirmed by the Spiegelberg criteria.

Use of Methotrexate in Gynecologic and Obstetric Practice: What the Radiologist Needs to Know

Methotrexate (MTX) is the primary pharmaceutical agent that is used for management of disorders arising from trophoblastic tissue. Its widespread international use is mostly attributable to its noninvasive, safe, and effective characteristics as a treatment option for ectopic pregnancy (EP) and gestational trophoblastic disease (GTD), with the large added benefit of fertility preservation. Although the effects of MTX usage are well documented in the gynecologic and obstetric literature, there is a scarcity of radiologic literature on the subject. Depending on the type of EP, the route of MTX administration and dosage may vary. US plays an essential role in the diagnosis and differentiation of various types of EPs, pregnancy-related complications, and complications related to MTX therapy, as well as the assessment of eligibility criteria for MTX usage. A knowledge of expected imaging findings following MTX treatment, including variability in echogenicity and shape of the EP, size fluctuations, changes in vascularity and gestational sac content, and the extent of hemoperitoneum, is essential for appropriate patient management and avoidance of unnecessary invasive procedures. A recognition of sonographic findings associated with pregnancy progression and complications such as tubal or uterine rupture, severe hemorrhage, septic abortion, and development of arteriovenous communications ensures prompt patient surgical management. The authors discuss the use of MTX in the treatment of disorders arising from trophoblastic tissue (namely EP and GTD), its mechanism of action, its route of administration, and various treatment regimens. The authors also provide a focused discussion of the role of US in the detection and diagnosis of EP and GTD, the assessment of the eligibility criteria for MTX use, and the identification of the sonographic findings seen following MTX treatment, with specific emphasis on imaging findings associated with MTX treatment success and failure. Online supplemental material is available for this article. ^©RSNA, 2021.

Accuracy of first-trimester ultrasound in diagnosis of tubal ectopic pregnancy in the absence of an obvious extrauterine embryo: systematic review and meta-analysis

OBJECTIVES

To determine the accuracy of ultrasound in the diagnosis of a tubal ectopic pregnancy in the absence of an obvious extrauterine embryo.

METHODS

This was a systematic review conducted in accordance with the PRISMA statement and registered with PROSPERO. We searched MEDLINE, EMBASE and The Cochrane Library for relevant citations from database inception to July 2014. Studies were selected in a two-stage process and their data extracted by two reviewers. Accuracy measures were calculated for each ultrasound sign, i.e. empty uterus, pseudosac, adnexal mass and free fluid in the pouch of Douglas, alone and in various combinations. Individual study estimates were plotted in summary receiver-operating characteristics curves and forest plots for examination of heterogeneity. The quality of included studies was assessed.

RESULTS

Thirty-one studies including 5858 women were selected from 19,959 citations. Following meta-analysis, an empty uterus on ultrasound was found to predict an ectopic pregnancy with a sensitivity of 81.1% (95% CI, 42.1-96.2%) and specificity of 79.5% (95% CI, 68.9-87.1%). The corresponding performance of the pseudosac, adnexal mass and free fluid were: 5.5% (95% CI, 3.3-9.0%) and 94.2% (95% CI, 75.9-98.8%); 63.5% (95% CI, 48.5-76.3%) and 91.4% (95% CI, 83.6-95.7%); and 47.2% (95% CI, 33.2-61.7%) and 92.3% (95% CI, 85.6-96.0%), respectively.

CONCLUSION

Visualization of an empty uterus, adnexal mass, free fluid or a pseudosac has poor sensitivity for the diagnosis of a tubal pregnancy when an obvious extrauterine embryo is absent, but it has good specificity. We can therefore infer that ultrasound is more useful for 'ruling in' a tubal pregnancy than 'ruling out' one. However, the findings were limited by the poor quality of some included studies and heterogeneity in the index test and reference standard.

Imaging for acute pelvic pain in pregnancy

Acute pelvic pain in pregnancy presents diagnostic and therapeutic challenges. Standard imaging techniques need to be adapted to reduce harm to the foetus from X-rays because of their teratogenic and carcinogenic potential. Ultrasound remains the primary imaging investigation of the pregnant abdomen. Magnetic resonance imaging (MRI) has been shown to be useful in the diagnosis of gynaecological and obstetric problems during pregnancy and in the setting of acute abdomen during pregnancy. MRI overcomes some of the limitations of ultrasound, mainly the size of the gravid uterus. MRI poses theoretical risks to the foetus and care must be taken to minimise these with the avoidance of contrast agents. Teaching Points • Ultrasound and MRI are the preferred investigations for acute pelvic pain during pregnancy. • Ultrasound remains the primary imaging investigation because of availability and portability. • MRI helps differentiate causes of acute pelvic pain when ultrasound is inconclusive.

Adnexal sonographic findings in ectopic pregnancy and their correlation with tubal rupture and human chorionic gonadotropin levels

OBJECTIVES

To determine whether the distribution of transvaginal sonographic findings of ectopic pregnancy has changed since the studies done 20 years ago and to explore the correlation of tubal rupture with transvaginal sonographic findings and human chorionic gonadotropin (hCG) levels.

METHODS

Patients with ectopic pregnancy who underwent transvaginal sonography before treatment were included. Sonograms and medical records were retrospectively reviewed. The presence of a tubal ring, the presence of a yolk sac, embryonic cardiac activity, the degree of vascularity on color Doppler imaging, hCG levels, and results of surgery were recorded.

RESULTS

Our study included 231 ectopic pregnancies. A positive sonographic adnexal finding was present in 219 cases (94.8%): adnexal mass in 218 (94.4%) and a moderate-to-large amount of free fluid in 84 (36.4%). The adnexal masses were graded as follows: 1, nonspecific mass (125 cases [54.1% of total]); 2, tubal ring without a yolk sac or embryo (57 [24.7%]); 3, yolk sac but no embryonic heartbeat (19 [8.3%]); and 4, embryo with cardiac activity (17 [7.4%]). The mean hCG level increased as the grade ascended from 1 to 4. Thirty-six patients had tubal rupture at surgery within 24 hours of the sonogram. A moderate-to-large amount of free fluid was significantly associated with tubal rupture (P < .05) but had low sensitivity, specificity, and positive predictive value for rupture. Other sonographic findings and hCG levels were not significantly related to tubal rupture.

CONCLUSIONS

Transvaginal sonography showed an adnexal abnormality in nearly 95% of our patients with ectopic pregnancy, most commonly a nonspecific adnexal mass. Embryonic cardiac activity was seen in fewer than 10%. Neither sonographic findings nor hCG levels were useful predictors of tubal rupture.

Transvaginal ultrasound in fertile patients with suspected appendicitis: an experience report of current practice

Background. Transvaginal ultrasound (TVU) in female patients with acute right lower quadrant (RLQ) abdominal pain is time and infrastructure intensive and not always available. This study aims to evaluate the role of TVU in these patients. Methods. Retrospective analysis identified 224 female patients with RLQ pain and TVU. Results. TVU revealed an underlying pathology in 34 (15%) patients, necessitating a diagnostic laparoscopy in 12 patients. Six patients (2%) had a true gynaecological emergency. The remaining 23 patients did not require surgery. The other 190 patients with RLQ pain had a bland TVU; 127 (67%) were discharged, while 63 patients (33%) received a diagnostic laparoscopy. Conclusion. The incidence of true gynaecological emergencies requiring urgent surgical intervention is very low in our patient cohort. TVU is a helpful tool if performed by a physician who is well trained in TVU.

Diagnosis and management of ectopic pregnancy using bedside transvaginal ultrasonography in the ED: a 2-year experience

OBJECTIVES

The objective of this study was to describe diagnosis and management of ectopic pregnancy using bedside transvaginal ultrasound (US) in an established emergency US program.

METHODS

This was a retrospective study on patients presenting over a 2-year period performed at a level I urban academic emergency department (ED). The ED sees 78,000 patients annually and has a residency and active US program. Patients were eligible for inclusion if they were pregnant, seen in the ED for a first-trimester complication, and underwent a bedside emergency US suggesting an ectopic pregnancy. Emergency department US logs were reviewed for findings suggestive of ectopic pregnancy. Medical records were reviewed for history, physical examination findings, laboratory results, additional diagnostic testing, management, hospital course, and a discharge diagnosis by the admitting obstetric service (OB). Patients with incomplete data were excluded from analysis. Statistical analysis consisted of descriptive statistics.

RESULTS

Seventy-four patients ranging in age from 16 to 39 years (mean, 25 years) were included in the study. Eight patients with incomplete data were excluded from analysis. Emergency-physician US diagnoses included definite ectopic pregnancy (6/74), probable ectopic pregnancy (28/74), and possible ectopic pregnancy (40/74). Forty-seven (64%) of these patients were eventually diagnosed with definite ectopic pregnancy by the OB. During initial consultation, the OB disagreed with the diagnosis of ectopic pregnancy in 15 (32%) of the 47 eventual patients with ectopic pregnancy, calling them miscarriages. Other eventual diagnoses included 9 (12%) patients with possible ectopic pregnancy, 11 (14%) patients with miscarriage, and 7 (9%) with intrauterine pregnancy. Emergency sonologists found tubal rings in 9 (19%) patients with eventual ectopic pregnancy, complex adnexal mass in 29 (61%) patients, and a large amount of echogenic fluid in the cul-de-sac in 10 (21%) patients. Six (13%) patients had live ectopic pregnancy. The OB ordered a radiology US in 10 cases but did not change the diagnosis or management. Beta-human chorionic gonadotropin (beta-hCG) levels ranged from 41 to 59846 mIU/mL (mean, 4602 mIU/mL), but for live ectopic pregnancy, the range was 2118 to 59,846 mIU/mL (mean, 36,341 mIU/mL). Seventeen (36%) patients had beta-hCG levels of lower than 1000 mIU/mL. Of 47 eventual ectopic pregnancies, 29 (62%) patients underwent operative intervention, 17 (36%) patients received methotrexate, and 1 patient left against medical advice. Five (11%) of these patients with definite ectopic pregnancy were initially managed by emergency physicians with follow-up ED visits and serial US examinations without OB consultation.

CONCLUSION

Our study demonstrates that with increased experience, emergency sonologists can accurately diagnose ectopic pregnancy. Furthermore, patients at risk for ectopic pregnancy should not be denied US examinations if their beta-hCG levels fall below an arbitrary discriminatory zone.

Imaging of pelvic pain in the first trimester of pregnancy

Pelvic pain during the first trimester of pregnancy can pose a challenge to the clinician. The noninvasive nature, safety, and reliability of ultrasonography make it the diagnostic method of choice for pregnant patients who have pelvic pain. Sonography provides information that allows for diagnosis of both pregnancy-related pain, such as a ruptured ectopic pregnancy, miscarriage, or threatened abortion; and may be useful in the diagnosis of pain unrelated to pregnancy, such as that seen in appendicitis and nephrolithiasis.

"Rule out ectopic": Asking the right questions, getting the right answers

Sonographic evaluation of the pregnant patient suspected of harboring an ectopic pregnancy (EP) helps determine patient management. Although clinicians typically ask sonologists to "rule out" EP in these patients, the sonologist actually must answer 3 questions: (1) Is there an intrauterine pregnancy (IUP)? (2) Is the possibility of normally developing IUP reliably excluded? (3) Are there sonographic findings that identify or increase the likelihood of an EP? Understanding the rationale behind these questions and the sonographic findings that help to answer these questions enables the sonologist to contribute meaningfully to the care of patients with possible EP. Beginning the sonographic examination with a limited transabdominal approach has value. An IUP can be confidently diagnosed by identification of an intradecidual sac exhibiting the double decidual sac sign, yolk sac, or embryo. When the serum beta human chorionic gonadothropin exceeds 2000 mIU/mL, a technically excellent sonographic examination should identify an intradecidual sac potentially representing an IUP. Even without directly visualizing a yolk sac or embryo in the adnexa, the presence of an extraovarian mass or hemoperitoneum strongly predicts the possibility of EP. An intraovarian mass with peripheral hypervascularity is more likely to represent the corpus luteum rather than an intraovarian EP. Cervical EP can be distinguished from the cervical phase of a spontaneous abortion in progress by either demonstrating fetal heart motion or persistence or enlargement of findings on short-interval follow-up. Absence of a myometrial mantle surrounding one edge of an IUP positioned at the fundus is suspicious for an interstitial EP.

Serum biochemistry correlates with the size of tubal ectopic pregnancy on sonography

OBJECTIVE

To investigate whether there is a correlation between serum biochemistry (human chorionic gonadotropin (hCG), CA 125, progesterone and estradiol) and the common sonographic findings (blob sign, bagel sign or extrauterine gestational sac with cardiac activity) or size of a tubal ectopic pregnancy, and whether there is a difference in serum biochemistry between women with a tubal ectopic pregnancy who are hemodynamically unstable (tachycardia, hypotension, falling hemoglobin levels and/or acute severe abdominal pain) and those who are hemodynamically stable.

METHODS

This was a prospective cohort study of 106 women with a tubal ectopic pregnancy. We noted transvaginal ultrasound examination findings including adnexal mass size, and the serum levels of hCG, CA 125, progesterone and estradiol. The data were analyzed retrospectively.

RESULTS

The mean maternal and gestational ages were 30.7+/-5.7 years and 44+/-4.2 days, respectively. There was no correlation between serum markers and common sonographic findings. However, in the presence of the bagel sign on ultrasound, hemodynamic stability was more common (P=0.03). The mean serum hCG concentrations in tubal ectopic pregnancies<20 mm, 20-40 mm and >40 mm in size were 2225.3+/-3166.9, 4124.8+/-6121.4, and 11 011.8+/-12 670.1 IU/mL, respectively (P<0.001). Serum hCG, CA 125 and estradiol values were well correlated with adnexal mass size; for CA 125 this correlation was linear. There was no difference in serum biochemistry between hemodynamically stable and hemodynamically unstable women.

CONCLUSION

Common sonographic findings of tubal ectopic pregnancy do not correlate with serum biochemistry. High levels of CA 125, hCG or estradiol may suggest a larger adnexal mass in women with uncomplicated tubal pregnancies. Hemodynamically stable and hemodynamically unstable women do not differ in their serum biochemistry.

Ectopic pregnancy: a review

Ectopic pregnancy is a major clinical problem, occurring in 75,000 cases per year in the United States. With in vitro fertilization, embryo transfer, microsurgical techniques, and better early diagnosis, the rates of ectopic pregnancies have increased. Transvaginal sonography along with beta-human chorionic gonadotrophin monitoring are the standards for evaluation of suspected ectopic pregnancy. When ectopic pregnancy is present, transvaginal sonography most often demonstrates an adnexal finding directly related to the extra-uterine gestation itself, a hematoma caused by it, or both. Although tubal location is most common, it is important to recognize unusual locations of ectopic pregnancy such as isthmic, cervical, ovarian, and abdominal. Ultrasound is the mainstay of diagnosis, but magnetic resonance imaging can be helpful in unusual or complicated cases. Current therapeutic options for an ectopic pregnancy are expectant management, systemic methotrexate injections, sonographically guided minimal invasive treatment, and surgery. This review encompasses diagnosis, treatment, and management of ectopic pregnancy.

Preconceptions versus experience of transvaginal ultrasonography in older women

OBJECTIVE

To determine whether women find that having a transvaginal ultrasound scan is better or worse than they had expected.

METHODS

Fifty-four consecutive women in an ovarian cancer screening trial filled in linked questionnaires before and after having a transvaginal ultrasound scan.

RESULTS

The women found that having a transvaginal scan was less painful (P = 0.003) and less embarrassing (P = 0.001) than they had expected. They found it less uncomfortable than expected in comparison to having mammography (P = 0.013) or a cervical smear (P = 0.004).

CONCLUSIONS

Women attending for a transvaginal scan can be reassured that it will not be as painful or embarrassing as they fear, and that it is not as uncomfortable as having mammography or a cervical smear.

Tolerability of transvaginal ultrasonography as an ovarian cancer screening test

OBJECTIVE

To evaluate the acceptability of transvaginal ultrasonography as a screening tool.

DESIGN

Prospective survey of women attending for screening within a randomised controlled trial.

SETTING

University Hospital in Teesside.

PARTICIPANTS AND METHODS

54 women completed a questionnaire immediately after their first transvaginal ultrasound scan.

RESULTS

52 of 54 (96%) questionnaires were suitable for full analysis. The women were unlikely to find the scan was painful, 47 vs three (p<0.001), or embarrassing 45 vs five (p<0.001). Women were more likely to find both a smear, 42 vs eight (p<0.001) and a mammogram, 47 vs two (p<0.001) was more uncomfortable than transvaginal ultrasonography.

CONCLUSIONS

Transvaginal ultrasonography is an acceptable tool for screening for ovarian cancer. It is better tolerated than other screening tools such as cervical smear and mammography.

Ectopic pregnancy versus corpus luteum cyst revisited: best Doppler predictors

OBJECTIVE

To determine the best Doppler values for differentiating ectopic pregnancy from a corpus luteum cyst of pregnancy.

METHODS

This was a prospective study of 80 consecutive patients with the diagnosis of ectopic pregnancy. All ectopic pregnancies were diagnosed on the basis of the presence of an extra-ovarian adnexal mass on sonography and were confirmed surgically. The last menstrual period ranged from 4 to 11 weeks (mean, 6.3 weeks), and the maximal ectopic pregnancy diameter ranged from 0.7 to 5.5 cm (mean, 2.5 cm). Seventy-six ectopic pregnancies showed color vascularity, and 40 showed corpus luteum cysts with vascular walls. The highest peak systolic velocity and the lowest resistive index of the vascular ectopic pregnancies were compared with the corresponding values in the vascular corpus luteum cysts.

RESULTS

The mean peak systolic velocity of the ectopic pregnancies was 35.4 cm/s compared with 28.4 cm/s in corpus luteum cysts, with no significant statistical difference (P = .1). The resistive index of the ectopic pregnancies ranged from 0.15 to 1.6 (mean +/- SD, 0.61 +/- 0.24) compared with 0.39 to 0.7 (mean, 0.52 +/- 0.10) in corpus luteum cysts, with a significant statistical difference (P = .003). In this cohort, a resistive index of less than 0.39 had a specificity of 100% and a positive predictive value of 100% for diagnosing ectopic pregnancy but was present in only 15% (confidence interval, 7%-23%) of ectopic pregnancies. A resistive index of greater than 0.7 had a specificity of 100% and a positive predictive value of 100% for diagnosing ectopic pregnancy and was present in 31% (confidence interval, 21%-41%) of ectopic pregnancies.

CONCLUSIONS

Both low and high resistive indices discriminate ectopic pregnancy from a corpus luteum cyst.

What's new in first trimester ultrasound

There are several advantages to ultrasound examination in early pregnancy. Ultrasound performed during the first trimester confirms an intrauterine pregnancy, establishes accurate dating, and is crucial in diagnosing early pregnancy failure and ectopic pregnancy. As sonographic spatial resolution continues to improve, first trimester sonography increasingly will offer early pregnancy screening for chromosomal abnormalities and fetal structural abnormalities.

Acute female pelvic pain: ultrasound evaluation

Ultrasound has become a valuable primary imaging tool in the assessment of acute pelvic pain in women, both for diagnosis and for assessment of complications. Although ultrasound is an established imaging tool for gynecologic diseases, it is also a useful modality for assessing nongynecologic disorders that cause acute pelvic pain, such as diverticulitis and urinary tract calculi. These are important differential diagnoses in women with acute pelvic pain, and sonologists are not always expert in their diagnosis. This article reviews the gamut of conditions that can cause acute pelvic pain in women. The usual gynecologic causes are included, such as ectopic pregnancy, but also considered are conditions such as diverticulitis, appendicitis, and incarcerated hernia, which are important differential considerations.

History and physical examination to estimate the risk of ectopic pregnancy: validation of a clinical prediction model

STUDY OBJECTIVE

To prospectively validate a clinical prediction model for ectopic pregnancy (EP).

METHODS

Prospective cohort with 14-month derivation and 12-month validation phases. All hemodynamically stable, first-trimester patients with abdominal pain or vaginal bleeding who presented to a military teaching hospital emergency department underwent follow-up until an outcome of intrauterine pregnancy (IUP) or EP was established. Patients were separated into the high-risk group, defined as having either peritoneal signs or definite cervical motion tenderness; intermediate-risk group, defined as the presence of pain or tenderness, other than midline cramping, plus absence of fetal heart tones, and absence of tissue visible at the cervical os; and low-risk group (neither high- nor intermediate-risk) using recursive partitioning.

RESULTS

Summarizing both phases, 915 patients had 845 (93%) IUPs and 70 (7.6%) EPs, with 18 (1.9%) lost to follow-up. The clinical prediction model classified 75 (8.2%) into the high-risk group (sensitivity 31%, 95% confidence interval [CI] 21% to 44%; specificity 94%, 95% CI 92% to 95%); and 644 (70%) in the intermediate-risk group (sensitivity 98%, 95% CI 89% to 100%; specificity 25%, 95% CI 22% to 29%). The remaining 196 (21%) patients who met neither high-risk nor intermediate-risk criteria were classified into the low-risk group. On the basis of EP prevalence of 7.7%, the risk of EP was less than 1% (95% CI 0% to 3%) for the low-risk group, 7% (95% CI 5% to 10%) for the intermediate-risk group, and 29% (95% CI 19% to 41%) for the high-risk group.

CONCLUSION

This clinical prediction model is useful for estimating the risk of EP in first-trimester patients, particularly when ancillary testing is equivocal or not readily available.

Derivation of a clinical prediction model for the emergency department diagnosis of ectopic pregnancy

OBJECTIVE

To derive a clinical prediction model for estimating the pretest probability of ectopic pregnancy in ED patients with first-trimester abdominal pain or vaginal bleeding.

METHODS

All hemodynamically stable first-trimester patients presenting to the ED of a tertiary care military teaching hospital over a 14-month period with a chief complaint of abdominal pain and/or vaginal bleeding had clinical data coded prior to determining outcome. They were then followed longitudinally until a criterion standard pregnancy outcome was established.

RESULTS

Of the 486 patients enrolled, 280 (58%) had viable intrauterine pregnancies, 167 (34%) had nonviable intrauterine pregnancies, and 39 (8%) had ectopic pregnancies. Using a recursive partitioning model, a high-risk group was derived (that was separated from intermediate and low-risk groups), consisting of patients with abdominal peritoneal signs or definite cervical motion tenderness, with a sensitivity of 31% (95% CI: 17-48%), a specificity of 93% (95% CI: 90-95%), a positive likelihood ratio of 4.3, and a negative likelihood ratio of 0.74. A low-risk group, consisting of patients with either fetal heart tones or tissue at the cervical os, or the absence of pain other than midline menstrual-like cramping and lacking any pelvic tenderness, was differentiated from an intermediate-risk group, with a sensitivity of 96% (95% CI: 81-100%), a specificity of 22% (95% CI: 18-26%), a positive likelihood ratio of 1.2, and a negative likelihood ratio of 0.17.

CONCLUSION

A clinical prediction model for estimating the probability of ectopic pregnancy in ED patients has been derived. It may prove to have practical clinical application for estimating pretest probability of ectopic pregnancy as well as assisting in medical decision making when laboratory and ultrasonographic findings are nondiagnostic. Clinical application should await prospective validation in an independent sample.

Endometrial color flow/image-directed Doppler imaging: negative predictive value for excluding ectopic pregnancy

PURPOSE

Visualization of an intrauterine pregnancy with transvaginal ultrasound virtually excludes an ectopic pregnancy. However, findings that might lower patients' risk for ectopic pregnancy have not been extensively investigated. We prospectively performed transvaginal color flow/image-directed Doppler imaging of the endometrium to determine the predictive value of endometrial blood flow for excluding ectopic pregnancy.

MATERIALS AND METHODS

From April 1994 to August 1995, 211 consecutive women underwent transvaginal ultrasound examination to exclude an ectopic pregnancy. Color flow/image-directed Doppler imaging of the endometrium was performed on each patient. Flow was considered to be present only if a Doppler signal could be obtained with the cursor located completely within the endometrium. All Doppler imaging parameters were optimized for each patient. Resistive indices were obtained if arterial signal was present, and receiver operator characteristic curves were constructed for RI and peak systolic velocity. Findings were correlated with surgical and pathology results.

RESULTS

Of 211 total patients, there were 55 ectopic pregnancies (52 diagnosed for a sensitivity of 95%), 89 incomplete spontaneous abortions, 40 completed spontaneous abortions, and 27 intrauterine pregnancies. Of 55 ectopic pregnancies diagnosed with real time imaging, 9 had areas of endometrial blood flow (6 venous, 3 arterial), and 46 did not. Of the 156 patients that did not have an ectopic pregnancy, 107 had arterial blood flow within the endometrium, and 49 had no flow. Using only cases with arterial signal, the negative predictive value of endometrial blood flow for excluding an ectopic pregnancy was 97% (107/107 + 3). The optimal cutoff values (5% false-positive rate) for peak systolic velocity and refractive index (RI) were 15 cm/s and 0.55.

CONCLUSIONS

Arterial blood flow within the endometrium lowers the risk for ectopic pregnancy even when other findings that might indicate a high risk are present. Venous flow within the endometrium does not exclude an ectopic pregnancy.

Ectopic pregnancy--Part II: Diagnostic procedures and imaging

Ectopic pregnancy is an increasingly common and potentially catastrophic condition in which the patient often presents to the ED with abdominal pain or vaginal bleeding. Recent developments in the laboratory (sensitive beta hCG assays, progesterone assays), in ultrasonography (transvaginal probes, Doppler ultrasonography), and in the combination of modalities (discriminatory zone of beta hCG for ultrasonographic evidence of IUP) have allowed the earlier diagnosis of ectopic pregnancy, with the potential for a reduction in maternal mortality and morbidity. Understanding the strengths and limitations of the variety of diagnostic modalities available will allow the clinician to formulate a rational strategy for the early diagnosis of ectopic pregnancy. Numerous algorithms have been developed. All begin with high clinical suspicion for women of reproductive age with abdominal/pelvic pain or vaginal bleeding. Pregnancy testing with a sensitive beta hCG qualitative test is next. For stable patients found to be pregnant, sonography generally follows (often first transabdominally then transvaginally). Unstable patients require immediate resuscitation and gynecology consultation; invasive diagnostic methods may supplant laboratory studies and sonography. Unclear cases may necessitate the use of quantitative beta hCG (discriminatory zone), other pregnancy hormones (progesterone), invasive procedures (laparoscopy, culdocentesis, D&C), or observation (serial beta hCGs). A suggested algorithm incorporating these elements is shown (Fig. 1).

Unruptured interstitial pregnancy: a pitfall of MR imaging

We report two cases with interstitial pregnancy, which showed completely different MR appearances. In case 1, a gestational sac was demonstrated and the diagnosis of ectopic pregnancy was straightforward. In case 2, a hypervascular mass was shown without demonstration of a gestational sac, the findings usually seen in gestational trophoblastic disease (GTD). MR imaging may play some role in the diagnosis of interstitial pregnancy when sonography is insufficient or equivocal. If GS is visualized, diagnosis is easy. However, if not, the appearance may have a spectrum and can be similar to GTD.

The discriminatory human chorionic gonadotropin zone for endovaginal sonography: a prospective, randomized study

OBJECTIVE

To determine the probability of detecting the gestational sac of a normal intrauterine pregnancy by vaginal ultrasound at different gestational ages and serum hCG concentrations.

DESIGN

Prospective, randomized study.

SETTING

Pregnant human volunteers in a university-based clinical research environment.

PATIENTS

Women with viable pregnancies who conceived spontaneously or after ovulation induction.

INTERVENTIONS

Vaginal ultrasound and serum hCG determinations were performed between 20 and 30 days after conception. The timing of the tests was determined randomly.

MAIN OUTCOME MEASURE

Detection of gestational sac.

RESULTS

The probability of detecting a gestational sac increased significantly with both gestational age and serum hCG concentration, but the regression on gestational age fitted the data much better than the regression on loge (hCG). The probability of detecting a sac was similar in multiple and singleton pregnancies of the same gestational age but, for a given hCG concentration, the probability of detecting a sac was lower for multiple than for singleton pregnancies because multiple gestations were associated with higher serum hCG concentrations than singleton pregnancies of the same gestational age.

CONCLUSION

If it is known, gestational age rather than the serum hCG concentration should be used to determine whether the gestational sac of an intrauterine pregnancy should be detectable by vaginal ultrasound. Failure to image a gestational sac > or = 24 days after conception is presumptive evidence of an ectopic pregnancy. Reliance on serum hCG rather than gestational age may lead to an erroneous diagnosis of ectopic pregnancy in women with multiple pregnancies.

Transvaginal ultrasonographic findings in surgically verified ectopic pregnancy

OBJECTIVE

Our purpose was to evaluate transvaginal ultrasonographic findings in ectopic pregnancies for positive ultrasonographic sign(s).

STUDY DESIGN

Eighty-nine patients admitted with an ectopic pregnancy from September 1987 through September 1989 were retrospectively reviewed. Sixty-nine had undergone transvaginal ultrasonography within 10 days before surgery. The ultrasonographic examinations were reviewed by four radiologists.

RESULTS

Ultrasonography revealed adnexal masses in 54 patients (78%). Thirty-six masses had an appearance consistent with an adnexal ring. Twenty-four adnexal rings demonstrated a thin sonolucent area surrounding the ring, a "halo sign" (67%). A control group of 116 intrauterine pregnancies were evaluated by ultrasonography. Forty-one women had adnexal cysts. Twenty-seven of these had an adnexal ring; only two of these had halos.

CONCLUSION

The halo sign is presumptive evidence of a living ectopic pregnancy and, when identified, may allow earlier diagnosis and intervention.

Hysteroscopic diagnosis of ectopic pregnancy

Although vaginal ultrasonography combined with plasma beta-hCG determination can provide a reliable diagnosis and location of ectopic pregnancy, the results can be difficult to interpret in the early stages when hCG levels are low. Hysteroscopy can be used in such cases to differentiate between ectopic pregnancy and non-viable uterine pregnancy when viable uterine pregnancy has been ruled out. General anaesthesia and laparoscopy are avoided. We performed 60 hysteroscopic procedures between January 1989 and December 1990 in patients with suspected ectopic pregnancies. The pregnancy had been located by means of vaginal ultrasonography in every case in which the hCG was above 1500 IU/ml and in 36% of cases in which the beta-hCG was below this level. Hysteroscopy was hindered by metrorrhagia in three cases and was inconclusive in one, necessitating laparoscopy. Diagnosis was possible in all the remaining cases, as follows: ectopic pregnancy in 41 cases, with an empty uterus and occasional bleeding from an ostium; non-viable uterine pregnancy in 18 cases, with the presence of material within the cavity. Hysteroscopy therefore confirmed the diagnosis in 55% of the cases and was itself diagnostic in a further 43% of cases. Its sensitivity for the diagnosis of ectopic pregnancy was 100% and its specificity 95%. We propose a diagnostic decision tree.

Preoperative Diagnosis of Third Trimester Abdominal Pregnancy by Transvaginal Ultrasound

Abdominal pregnancy is a potentially lethal condition that is often misdiagnosed. A clinically suspected abdominal pregnancy at 31 gestational weeks was demonstrated by transvaginal sonogram and confirmed at laparotomy.

Pictorial essay: transabdominal and endovaginal sonography of adnexal masses

Endovaginal sonography is rapidly becoming the diagnostic procedure of choice when evaluating patients with early pregnancy and assessing uterine abnormalities. However, there has been relatively little discussion of endovaginal sonography in the evaluation of adnexal masses. Using endovaginal sonography we studied 50 patients with clinically suspected adnexal masses, in whom transabdominal sonography was either suboptimal or failed to adequately characterize the mass. The purpose of this pictorial essay is to depict the normal anatomy of the ovaries and adnexa and highlight the unique contribution of endovaginal sonography in diagnosing a variety of adnexal masses, including tubal and ovarian lesions.

Transvaginal ultrasound in a children's hospital: is it worthwhile?

We report our experience with transvaginal sonography (TVS) in 35 nonpregnant adolescent and young teenage females referred for pelvic sonography. We assessed the efficacy of TVS as compared to transabdominal sonography (TAS) in 40 examinations. Of the 40 examinations, there were 5 discrepancies. In 4, abnormalities were detected on TVS not seen on TAS. In one there was a false-positive TAS with bowel recognized as such on TVS. Image quality (clarity, completeness, anatomic detail) was judged better by two reviewers on TVS in 85% of cases but additional useful information given in 58% of patients. TVS provided greater diagnostic confidence in 30% of patients with possible PID by better demonstration of fluid in the endometrial canal, pyosalpinx or tubo-ovarian abscess, or by better characterization of free pelvic fluid. The average scan time required for TVS was 8 minutes. TVS was better tolerated than TAS in the majority of patients. TVS is a relatively easy, rapid imaging technique that is well tolerated. It enhances anatomic detail and helps to elucidate unclear findings on TAS. TVS is also helpful in obese patients and those unable to maintain a full bladder. It should be considered a useful and worthwhile adjunct to TAS in the evaluation of adolescents and teenagers with pelvic diseases.

Transabdominal and transvaginal ultrasonography in the diagnosis of ectopic pregnancy: a comparative study

Thirty-four patients believed to have ectopic pregnancies were examined by transabdominal and transvaginal ultrasonography. Twenty-five patients had tubal pregnancy confirmed operatively within 24 hours after ultrasonographic examination. In these cases adnexal findings highly suspicious for ectopic pregnancy were found in 68% of cases by transabdominal ultrasonography and in 84% by transvaginal ultrasonography. A distinct adnexal gestational sac was apparent in 32% of cases by transabdominal ultrasonography and in 64% of cases by transvaginal ultrasonography. Transvaginal ultrasonography was significantly more accurate (p less than 0.01) in identifying an adnexal gestational sac and allows more detailed adnexal imaging.

Ultrasound evaluation of ectopic pregnancy including correlation with human chorionic gonadotrophin levels

A total of 267 patients referred for ultrasound examination because of clinical suspicion of ectopic pregnancy were studied prospectively. The outcome was correlated with the ultrasound findings and human chorionic gonadotrophin levels using a quantitative serum assay. The value of the following in the diagnosis of ectopic pregnancy are assessed: ultrasound criteria for early diagnosis of intrauterine pregnancy before visualization of a viable fetus, the discriminatory zone of hCG and extrauterine abnormalities.

Transvaginal ultrasonography in patients at risk for ectopic pregnancy

Transvaginal ultrasonography was performed in 139 patients at risk for ectopic pregnancy. Among these patients, 22 ectopic pregnancies and 117 intrauterine pregnancies were eventually confirmed. Transvaginal ultrasonography definitively identified 18 of 22 (82%) ectopic pregnancies at initial evaluation by either direct visualization of an ectopically placed gestational sac (N = 14) or failure to visualize an intrauterine gestational sac combined with a level of the beta-subunit of human chorionic gonadotropin greater than 1300 mIU/ml (First International Reference Preparation) (N = 4). Transvaginal ultrasonography definitively diagnosed 103 of 117 (88%) intrauterine pregnancies at initial evaluation. Eighteen patients could not be definitively diagnosed by transvaginal ultrasonography at initial evaluation because nonvisualization of a gestational sac and a beta-subunit of human chorionic gonadotropin value less than 1300 mIU/ml. Evaluation of this group with serial measurements of beta-subunit of human chorionic gonadotropin, repeat ultrasonography, or both, revealed ectopic gestation (N = 4), early intrauterine pregnancy (N = 4), and complete abortion (N = 10).