Temporal ultrasound findings in the first trimester of a dual fetal demise occurring in a monochorionic diamniotic twin gestation

Single fetal demise in monochorionic gestations in the 2nd and 3rd trimester is associated with adverse outcomes for the co-twin. We present a case of single demise in a monochorionic gestation in the 1st trimester with evidence of subsequent hemodynamic aberrations in the co-twin, supportive of feto-fetal hemorrhage occurring early in gestation.

Pregnancy-associated Breast Cancer: Why Breast Imaging During Pregnancy and Lactation Matters

Pregnancy-associated breast cancer is characterized as breast cancer diagnosed during pregnancy, within the first postpartum year, or during lactation. It usually presents as a palpable mass, although the large majority of palpable masses during pregnancy are benign. Breast cancer is the most common invasive malignancy diagnosed during pregnancy and lactation, and its incidence is increasing as more women delay childbearing. Understanding the appropriate methods for screening and diagnostic workup of breast findings in this population is imperative for radiologists to promptly diagnose pregnancy-associated breast cancer. Use of available imaging modalities should be tailored to patient-specific factors, with US typically the first-line modality due to patient age and decreased sensitivity of mammography in the setting of lactational changes. This article illustrates the spectrum of imaging appearances of pregnancy-associated breast cancer, the appropriate diagnostic imaging workup, and the unique challenges encountered in evaluation of this patient population.

Diagnosis and Management of 2 Cases of Spontaneous Septostomy: Monochorionic/Dichorionic Hybrid Twin Gestation and Dichorionic Triamniotic Triplet Gestation

INTRODUCTION

Spontaneous septostomy is a rare complication of multiple gestations. Related complications include cord entanglement and preterm delivery. Limited data exist to guide the management of these high-risk patients. The majority of spontaneous septostomy cases have been reported in monochorionic diamniotic twins. We present 2 cases of spontaneous septostomy occurring in a monochorionic/dichorionic hybrid twin gestation (chorionicity transitions from dichorionicity to monochorionicity within the placenta) and in a dichorionic triamniotic triplet gestation.

CASE PRESENTATION

Case 1 was a monochorionic/dichorionic hybrid twin gestation with a septostomy complicated by fetal parts of one twin protruding into the co-twin's sac as well as symptomatic polyhydramnios. Fetal magnetic resonance imaging confirmed the septostomy. Case 2 was a dichorionic triamniotic triplet gestation with septostomy and cord entanglement. Both patients were managed akin to a pseudo-monoamniotic gestation with serial ultrasound surveillance and eventual inpatient admission for heightened fetal monitoring. Case 1 underwent elective scheduled cesarean delivery at 33 weeks, and case 2 underwent emergent cesarean delivery for fetal heart rate decelerations at 28 weeks.

CONCLUSION

With a high degree of clinical suspicion, spontaneous septostomy can be diagnosed in uncommon settings such as hybrid twin gestations and higher order multiples. Management of such patients is individualized and may include a combination of heightened outpatient and inpatient surveillance.

Fetal Hepatomegaly: Causes and Associations

Fetal hepatomegaly is associated with significant fetal morbidity and mortality. However, hepatomegaly might be overlooked when numerous other fetal anomalies are present, or it might not be noticed when it is an isolated entity. As the largest solid organ in the abdomen, the liver can be seen well with US or MRI, and the normal imaging characteristics are well described. The length of the fetal liver, which can be used to identify hepatomegaly, can be determined by measuring the liver from the diaphragm to the tip of the right lobe in the sagittal plane. Fetal hepatomegaly is seen with infection, transient abnormal myelopoiesis, liver storage and deposition diseases, some syndromes, large liver tumors, biliary atresia, and anemia. Some of these diagnoses are treatable during the fetal period. Attention to the associated findings and specific hepatic and nonhepatic imaging characteristics can help facilitate more accurate diagnoses and appropriate patient counseling.^©RSNA, 2020.

Adenomyosis in Pregnancy: Diagnostic Pearls and Pitfalls

Adenomyosis is a common benign uterine disorder in which ectopic endometrial glands extend into the myometrium. Adenomyosis is increasingly diagnosed in young women, affecting 20%-35% of women of reproductive age. Features of adenomyosis can be seen with either US or MRI, especially with newer imaging technology. With advances in reproductive endocrinology as well as a trend toward later maternal age, adenomyosis is increasingly noted during pregnancy, often while performing imaging for other reasons. Hormonal changes during pregnancy alter the appearance of adenomyosis, which includes diffuse, focal, and cystic adenomyosis. Recognizing these imaging changes in pregnancy proves essential for accurately diagnosing adenomyosis as a benign condition, as it mimics serious placental and myometrial abnormalities. Using a lower-frequency US transducer or MRI can be helpful in distinguishing among these entities. Describing the location of adenomyosis in relationship to the site of placentation is also important. Diagnosing adenomyosis is crucial because it can be associated with poor pregnancy outcomes, including spontaneous abortion, preterm birth, and fetal growth restriction. Adenomyosis is also a risk factor for preeclampsia. Intramural ectopic pregnancy is a rare but serious condition that can mimic cystic adenomyosis, and comparison with prepregnancy images can help differentiate the two conditions. The authors review the unique imaging characteristics of adenomyosis in pregnancy, focusing on accurate diagnosis of an underrecognized benign condition that can mimic myometrial and placental pathologic conditions.^©RSNA, 2021.

Medical Student Ultrasound Education: The Radiology Chair Weighs In

ABSTRACT

To assess the radiology department chairs' opinions concerning current status and plans for teaching ultrasound to medical students, the American College Taskforce on Radiology Ultrasound Education, commissioned by the American College of Radiology, distributed a survey to 142 radiology chairs and a medical school dean subgroup.The response rate was 30% (42/142), and 76% indicated ultrasound was currently part of the medical student curriculum. In preclinical years, radiology involvement was only 6.4%. During clinical years, radiology led ultrasound education with 51.7% in general and 82.9% in elective rotations. Regarding actual content, top 4 results were evenly distributed between learning hands-on scanning (81.1%), diagnostic use of ultrasound (75.7%), anatomy/pathology (75.7%), and ultrasound guidance for procedures (54.0%). Educational leaders in preclinical courses were emergency medicine (72.7%) followed by radiology (45.4%) physicians. During clinical years, leaders were radiology (52.6%) and emergency medicine (47.4%) physicians. Most chairs stated that knowledge of diagnostic ultrasound should be mandatory (76.2%), stressing the importance of teaching the diagnostic capabilities and uses of ultrasound as the primary goal (78.8%). Perceived barriers to implementation were evenly distributed between lack of space in the curriculum (55.6%), lack of faculty (48.2%), lack of resources (44.4%), and lack of institutional support (40.7%). The American College Taskforce on Radiology Ultrasound Education survey shows that radiology's role in ultrasound undergraduate education occurs almost exclusively during clinical years, and the chairs voice a desire to improve upon this role. Barriers include both intradepartmental (faculty and resources) and institutional (curricular) factors.

Mapping the Ultrasound Landscape to Define Point-of-Care Ultrasound and Diagnostic Ultrasound: A Proposal From the Society of Radiologists in Ultrasound and ACR Commission on Ultrasound

Current descriptions of ultrasound evaluations, including use of the term "point-of-care ultrasound" (POCUS), are imprecise because they are predicated on distinctions based on the device used to obtain images, the location where the images were obtained, the provider who obtained the images, or the focus of the examination. This is confusing because it does not account for more meaningful distinctions based on the setting, comprehensiveness, and completeness of the evaluation. In this article, the Society of Radiologists in Ultrasound and the members of the American College of Radiology Ultrasound Commission articulate a map of the ultrasound landscape that divides sonographic evaluations into four distinct categories on the basis of setting, comprehensiveness, and completeness. Details of this classification scheme are elaborated, including important clarifications regarding what ensures comprehensiveness and completeness. Practical implications of this framework for future research and reimbursement paradigms are highlighted.

Clinical outcomes following prenatal diagnosis of asymmetric ventriculomegaly, interhemispheric cyst, and callosal dysgenesis (AVID)

OBJECTIVES

When identified prenatally, the imaging triad of asymmetric ventriculomegaly, interhemispheric cyst, and dysgenesis of the corpus callosum (AVID) can indicate a more serious congenital brain anomaly. In this follow-up series of 15 fetuses, we present the neurodevelopmental outcomes of a single institution cohort of children diagnosed prenatally with AVID.

METHODS

Our fetal ultrasound database was queried for cases of AVID between 2000 and 2016. All available fetal MR imaging studies were reviewed for the presence of (a) interhemispheric cysts or ventricular diverticula and (b) dysgenesis or agenesis of the corpus callosum. Clinical records were reviewed for perinatal management, postnatal surgical management, and neurodevelopmental outcomes.

RESULTS

Fifteen prenatal cases of AVID were identified. Twelve were live-born and three pregnancies were terminated. Of the 12 patients, 11 underwent neurosurgical intervention. Of the eight patients surviving past infancy, seven of eight have moderate to severe neurodevelopmental delays or disabilities, encompassing both motor and language skills, and all have variable visual abnormalities.

CONCLUSION

In our cohort of 15 prenatally diagnosed fetuses with AVID, eight survived past infancy and all have neurodevelopmental disabilities, including motor and language deficits, a wide range of visual defects, craniofacial abnormalities, and medical comorbidities.

Intrauterine Linear Echogenicities in the Gravid Uterus: What Radiologists Should Know

Intrauterine linear echogenicity (ILE) is a common ultrasonographic finding in the gravid uterus and has variable causes and variable maternal and fetal outcomes. Correctly categorizing ILE during pregnancy is crucial for guiding surveillance and advanced imaging strategies. Common causes of ILE include membranes in multiple gestations, uterine synechiae with amniotic sheets, and uterine duplication anomalies. Less common causes include circumvallate placenta, chorioamniotic separation, and hemorrhage between membranes. Amniotic band syndrome is a rare but important diagnosis to consider, as it causes severe fetal defects. Imaging findings enable body stalk anomaly, a lethal defect, to be distinguished from amniotic bands, which although destructive are not necessarily lethal. This review describes the key imaging findings used to differentiate the various types of ILE in pregnancy, thus enabling accurate diagnosis and appropriate patient counseling. Online supplemental material is available for this article. ^©RSNA, 2018.

Sonographic detection of an infected maternal urachal cyst during pregnancy

Infection of a maternal urachal cyst during pregnancy is rare; Sonography is an important diagnostic tool that can help minimize maternal and fetal complications. We describe the case of a 35-year-old multiparous woman presenting in the third trimester with 2 weeks of fever, abdominal pain, and urinary symptoms. Imaging showed a 5-cm complex anterior midline mass, found intraoperatively to be eroding into the uterus. Sonographic imaging aided in the diagnosis and management of the urachal cyst, and antepartum sonographic measurements of the lower uterine segment helped to counsel regarding a trial of labor. Following treatment, the patient stabilized and had an uncomplicated vaginal delivery.

Radiological appearances of corpus luteum cysts and their imaging mimics

PURPOSE

To review the radiological appearances of corpus luteum cysts and their imaging mimics.

CONCLUSION

Corpus luteum cysts are normal post-ovulatory structures seen in the ovaries through the second half of the menstrual cycle and the first trimester of pregnancy. The typical appearance, across all modalities, is of a 1- to 3-cm cyst with a thick crenulated vascularized wall. Occasionally, similar imaging findings may be seen with endometrioma, ectopic pregnancy, tuboovarian abscess, red degeneration of a fibroid, and ovarian neoplasia. In most cases, imaging findings are distinctive and allow for a confident and accurate diagnosis that provides reassurance for patients and referring physicians and avoids costly unnecessary follow-up.

Antenatal sonographic diagnosis of choledochal cyst: Case report and imaging review

In this report, we present the antenatal two- and three-dimensional sonographic findings from a fetus with choledochal cyst as well as confirmatory postnatal MRI. A delayed diagnosis of choledochal cyst is common, leading to significant morbidity and mortality. Visualizing bile ducts entering a right upper quadrant cyst is pathognomonic, and early diagnosis can facilitate definitive treatment with Roux-en-Y hepaticojejunostomy.

Imaging and differential diagnosis of suprarenal masses in the fetus

Prenatal sonography and magnetic resonance imaging of suprarenal fetal masses is presented, along with clinical information and follow-up. Imaging pearls and differential considerations for each diagnosis will be discussed. Fetal suprarenal mass diagnoses include neuroblastoma, extralobar pulmonary sequestration, congenital adrenal hyperplasia, partial multicystic dysplastic kidney, renal duplication, urinoma, gastric duplication cyst, and splenic cyst. Recognizing the range of malignant and benign suprarenal fetal masses that can present on prenatal imaging can help guide patient counseling and management.

Asymmetric ventriculomegaly, interhemispheric cyst, and dysgenesis of the corpus callosum (AVID): an imaging triad

A series of 20 cases from 2 academic institutions is presented with a characteristic imaging triad of asymmetric ventriculomegaly, a large interhemispheric cyst, and partial or complete agenesis of the corpus callosum. Most cases were initially referred as aqueduct stenosis and hydrocephalus or focal porencephaly. We describe the imaging findings that identify an abnormal or absent corpus callosum associated with a type 1 interhemispheric cyst in fetuses initially thought to have hydrocephalus attributable to aqueductal stenosis. We suggest that the acronym AVID (asymmetric ventriculomegaly, interhemispheric cyst, and dysgenesis of the corpus callosum) may be useful in recognition of these cases. All cases presented with markedly asymmetric ventriculomegaly on initial sonography, with progressive hydrocephalus throughout gestation. Fetal magnetic resonance imaging was performed in 15 of 20 cases. Thirteen of 20 cases were identified in male fetuses. Associated fetal and postnatal abnormalities are also reported. Technological improvements in sonography and fetal magnetic resonance imaging allow improved characterization of associated intracranial anomalies in the setting of hydrocephalus. Accurate diagnosis can aid parental counseling, especially because isolated aqueductal stenosis suggests a better prognosis than hydrocephalus with anomalies. Markedly asymmetric ventriculomegaly in this series was the key to excluding isolated aqueductal stenosis and was associated with callosal malformation with a type 1a interhemispheric cyst.

Terminal myelocystocele and sacrococcygeal teratoma: a comparison of fetal ultrasound presentation and perinatal risk

This case exemplifies the difficulty in differentiating cystic sacrococcygeal teratoma and terminal myelocystocele. Fetal sonography presentation and perinatal risks of sacrococcygeal teratoma and terminal myelocystocele are compared, and we emphasize the importance of obtaining fetal MR imaging to establish an accurate diagnosis.

Platelet count/spleen diameter ratio for the noninvasive diagnosis of esophageal varices: results of a multicenter, prospective, validation study

BACKGROUND AND AIMS

Noninvasive assessment of esophageal varices (EV) may improve the management of patients with cirrhosis and decrease both the medical and financial burden related to screening. In this multicenter, international study, our aim was to prospectively validate the use of the platelet count/spleen diameter ratio for the noninvasive diagnosis of EV.

METHODS

A total of 218 cirrhotic patients underwent screening endoscopy for EV. Platelet count/spleen diameter ratio ((N/mm3)/mm) was assessed in all patients and its diagnostic accuracy was calculated. On the basis of previous results, a platelet count/spleen diameter ratio cutoff of 909 was applied to this population. The diagnostic accuracy of the platelet count/spleen diameter ratio was further evaluated for both severity and etiology of disease subgroups.

RESULTS

Prevalence of EV was 54.1%. The platelet count/spleen diameter ratio had 86.0% (95% CI, 80.7-90.4%) diagnostic accuracy for EV, which was significantly greater as compared with either accuracy of platelet count alone (83.6%, 95% CI 78.0-88.3%, P= 0.038) or spleen diameter alone (80.2%, 95% CI 74.3-85.3%, P= 0.018). The 909 cutoff had 91.5% sensitivity (95% CI 85.0-95.9%), 67.0% specificity (95% CI 56.9-76.1%), 76.6% positive predictive value, 87.0% negative predictive value, 2.77 positive likelihood ratio, and 0.13 negative likelihood ratio for the diagnosis of EV. Accuracy of the platelet count/spleen diameter ratio was maintained for both severity and etiology of disease subgroups.

CONCLUSIONS

The platelet count/spleen diameter ratio may be proposed as a safe and reproducible means to improve the management of cirrhotic patients who should undergo screening endoscopy for EV.

From the Archives of the AFIP

Fetal tumors are a diverse group of neoplasms, which are unique in their histologic characteristics, anatomic distribution, and pathophysiology. The biologic behavior of tumors in the fetus may differ dramatically compared with that of the same tumor detected later in life. Teratomas are the dominant histologic type and constitute the majority of both extracranial and intracranial neoplasms. Although often histologically mature, they may prove lethal because of their location and metabolic demands on the fetus. Large solid tumors may lead to cardiovascular compromise and hydrops fetalis. Extracranial teratomas are most commonly located in the sacrococcygeal area, followed by the head and neck, chest, and retroperitoneum. Fetuses with intracranial tumors have a poor prognosis regardless of histologic type. There are, however, two notable exceptions: lipomas and choroid plexus papillomas, both of which have a more favorable outcome. Neuroblastoma is the most common fetal malignancy. It may be either solid or cystic and is more often located on the right side. It typically has favorable biologic markers and stage at presentation. The prognosis for prenatally diagnosed cases is excellent. Other fetal neoplasms include soft-tissue tumors (both benign and malignant), leukemia, mesenchymal hamartoma of the kidney, and liver tumors (hemangioendothelioma, mesenchymal hamartoma, and hepatoblastoma).

Fetal ventricular mass determination on three-dimensional echocardiography: studies in normal fetuses and validation experiments

BACKGROUND

Estimation of ventricular volume and mass is important for baseline and serial evaluation of fetuses with normal or abnormal hearts. Direct measurement of chamber wall volumes and mass can be made without geometric assumptions by 3D fetal echocardiography. Our goals were to determine the feasibility of using fast nongated 3D echocardiography for fetal volumetric and mass assessments, to validate the accuracy of the ultrasound system and the measurement technique, and if satisfactory, to develop normal values for fetal ventricular mass during the second and third trimesters.

METHODS AND RESULTS

This was a prospective outpatient study of 90 consecutive normal pregnancies during routine obstetric services at Oregon Health & Science University (Portland). Optimized 3D volumes of the fetal thorax and cardiac chambers were rapidly acquired and later analyzed for right and left ventricular mass by radial summation technique from manual epicardial and endocardial traces. Experiments to validate the ultrasound system and measurement technique were performed with modified small balloon models and in vivo and ex vivo small animal experiments. Our study established the feasibility of fetal ventricular mass measurements with 3D ultrasound technology and developed normal values for right and left ventricular mass from 15 weeks' gestation to term.

CONCLUSIONS

Nongated fast 3D fetal echocardiography is an acceptable modality for determination of cardiac chamber wall volume and mass with good accuracy and acceptable interobserver variability. The method should be especially valuable as an objective serial measurement in clinical fetal studies with structurally or functionally abnormal hearts.

From the archives of the AFIP: tumors and tumorlike lesions of the testis: radiologic-pathologic correlation

Testicular carcinoma represents only 1% of all neoplasms in men, but it is the most common malignancy in the 15-34-year-old age group. Germ cell tumors constitute 95% of all testicular tumors. Germ cell tumors are a varied group of neoplasms whose imaging features reflect their underlying histologic characteristics. Seminomas are generally well-defined homogeneous lesions, whereas the nonseminomatous tumors (embryonal carcinoma, yolk sac tumor, choriocarcinoma, teratoma, and mixed germ cell tumor) have a much more varied appearance. Germ cell tumors follow a predictable pattern of spread via the lymphatic drainage to the retroperitoneal nodes. Choriocarcinoma, which has a proclivity for early hematogenous spread, is a notable exception. Testicular tumors may also arise from the sex cords (Sertoli cells) and stroma (Leydig cells). Although 90% of these tumors are benign, there are no reliable imaging criteria to differentiate them from malignant masses. Some benign testicular masses can be recognized, obviating an unwarranted orchiectomy. A dilated rete testis is a normal variant and appears as a series of small tubules near the mediastinum testis. Other benign lesions that can be suspected on the basis of imaging findings and history include intratesticular cysts, epidermoid cysts, congenital adrenal hyperplasia, and sarcoidosis.

Endometriosis: radiologic-pathologic correlation

Endometriosis is an important gynecologic disorder primarily affecting women during their reproductive years. Pathologically, it is the result of functional endometrium located outside the uterus. It may vary from microscopic endometriotic implants to large cysts (endometriomas). The physical manifestations are protean, with some patients being asymptomatic and others having disabling pelvic pain, infertility, or adnexal masses. Symptoms do not necessarily correlate with the severity of the disease. Ultrasonographic (US) features are variable and can mimic those of other benign and malignant ovarian lesions. Low-level internal echoes and echogenic wall foci are more specific US features for endometriomas. Magnetic resonance imaging improves diagnostic accuracy, with endometriotic cysts typically appearing with high signal intensity on T1-weighted images and demonstrating "shading" on T2-weighted images. The ovaries are the most common sites affected, but endometriosis can also involve the gastrointestinal tract, urinary tract, chest, and soft tissues. Small implants and adhesions are not well evaluated radiologically; therefore, laparoscopy remains the standard of reference for diagnosis and staging. Both medical and surgical treatment options are available depending on the patient's specific case.

Sonohysterography: technique, endometrial findings, and clinical applications

Transvaginal ultrasound-guided saline infusion sonohysterography (SHG) is a relatively new technique for evaluation of the uterine cavity. As new studies declare the clinical usefulness of this technique, SHG may quickly become part of the routine ultrasound evaluation of the female pelvis. In this article, the SHG procedure is described and normal findings are discussed. Common endometrial pathological findings such as atrophy, polyps, fibroids, hyperplasia, and carcinoma are reviewed. The newly touted roles of SHG for screening patients on long-term tamoxifen therapy and for evaluating patients with infertility are introduced. Finally, we present a practical ultrasound-based flow chart for the workup of menopausal and perimenopausal patients with abnormal uterine bleeding.

Amniotic fluid and the umbilical cord: the fetal milieu and lifeline

Amniotic fluid volume should be routinely assessed in every second and third trimester case. A review of amniotic fluid physiology and techniques for ultrasound evaluation of fluid volume is presented. The causes and significance of oligohydramnios and polyhydramnios are stressed. Umbilical cord abnormalities are often incidently observed at the time of amniotic fluid evaluation. The clinical significance of some common umbilical cord abnormalities such as a two-vessel cord and nuchal cord are discussed. Other, more uncommon entities such as cord mass lesions are also reviewed. Finally, the role of cord Doppler interrogation in determining fetal well-being is discussed.

Polyhydramnios and fetal intrauterine growth restriction: ominous combination

The purpose of this study was to evaluate the significance of polyhydramnios combined with intrauterine growth restriction. During a 6 year period, 39 fetuses were identified by prenatal sonography as having both polyhydramnios and intrauterine growth restriction. Polyhydramnios was defined as a four-quadrant amniotic fluid index of 24 or greater (mean 30.5, range 24 to 40). Intrauterine growth restriction was defined as estimated fetal weight less than the tenth percentile (Hadlock standards). The mean birth weight was 2213 g. Major anomalies were present postnatally in 92% (36 of 39) of fetuses. Among nine fetuses without sonographically detectable anomalies prenatally, six (67%) proved to have one or more anomalies at birth. Chromosome abnormalities were present in 38% (15 cases) including 10 fetuses with trisomy 18 and one with trisomy 13. The overall mortality rate was 59%. The combination of polyhydramnios and intrauterine growth restriction is ominous. The majority of fetuses have major anomalies or chromosome abnormalities, or both, even when other sonographic abnormalities are absent. Chromosome analysis and detailed fetal evaluation should be offered when polyhydramnios and intrauterine growth restriction are identified prenatally.

Postmortem fetal MR imaging: comparison with findings at autopsy

OBJECTIVE

The purpose of this study was to prospectively compare findings from postmortem fetal MR imaging with findings at autopsy.

SUBJECTS AND METHODS

Twenty-six fetuses were imaged on a 1.5-T MR scanner using two-dimensional and high-resolution three-dimensional fast spin-echo techniques immediately before autopsy. The MR images were reviewed independently by three radiologists who evaluated then for major and minor malformations. These findings were then compared with those at autopsy.

RESULTS

The 26 subjects had 47 major and 11 minor malformations. All three radiologists correctly identified 37 of the major malformations on the MR images (detection rate, 79%), and at least one of the three reviewers correctly identified 43 of the abnormalities (detection rate, 91%). Only one of the 11 minor anomalies was identified by any reviewer. Reviewers made six false-positive diagnoses. In two cases, both with major CNS malformations, MR imaging was superior to autopsy in defining in situ relationships.

CONCLUSION

Although autopsy remains the study of choice for evaluating causes of fetal death, MR imaging is an excellent alternative when autopsy is refused. Additionally, MR imaging may be a valuable adjunct to autopsy for fetuses with CNS anomalies.

The spectrum of first-trimester ultrasound findings

A wide spectrum of sonographic findings can be seen in the first trimester of pregnancy. One must have an appreciation of embryology to recognize normal and abnormal early pregnancy development. In this article we emphasize discriminatory criteria for identification of normal structures, as well as ultrasound findings in threatened abortion, failing pregnancy, multiple gestations, ectopic pregnancy, and trophoblastic disease. Sonoembryology, the identification of embryonic anatomy, is discussed, as are examples of early identification of anomalies.

Fetal gastrointestinal anomalies

A review of fetal gastrointestinal anomalies is presented. Normal abdominal development and anatomy, including basic embryology and recommended ultrasound techniques, are first outlined. Next is a more detailed discussion of the abnormal examination, including abdominal wall defects and intra-abdominal abnormalities. The goal of this work is to present a practical approach to the abnormal fetal abdominal examination enabling the sonographer and sonologist to suggest precise differential diagnoses.

First-trimester ultrasound: the essentials

A review of first-trimester ultrasound findings is presented. The normal first trimester, including practical embryology and pregnancy dating, is first discussed. Abnormal first-trimester findings, including sonographic evaluation of the failing pregnancy, ectopic pregnancy, gestational trophoblastic disease, and first-trimester cystic hygroma, are then stressed. This report reviews the spectrum of findings encountered by sonographers while evaluating early pregnancy.

The fetal thorax: noncardiac chest anomalies

Fetal thoracic anomalies often lead to pulmonary hypoplasia with subsequent fetal or neonatal demise. Therefore, in utero sonographic identification of these anomalies is important. Unlike cardiac anomalies, most noncardiac thoracic abnormalities are easily detected with ultrasound. An unusually small thorax is usually obvious to the experienced sonographer, and thoracic masses are commonly observed on the routinely obtained four-chamber view of the heart. This article reviews the many causes of pulmonary hypoplasia with an emphasis placed on thoracic masses. Many examples of pathological fetal thoracic conditions are provided as well as a listing of differential considerations with regard to sonographic appearances of chest masses.

The fetal heart: a practical sonographic approach

Structural abnormalities of the heart are a fairly common problem, affecting more than 8 of 1,000 newborns annually in the United States. Therefore, sonographic detection of these anomalies in utero is important. It is possible to detect a high percentage of fetal cardiac anomalies through proper sonographic examination using three central views of the heart: (1) the four-chamber view; (2) the aortic outflow tract view; and (3) the pulmonary output tract view. Although average sonologists may not be able to provide a precise diagnosis for a cardiac abnormality, they are able to recognize such abnormalities in a high percentage of cases by using these three views and by answering the following questions: (1) Is the heart in a normal position? (2) Is the heart size normal? (3) Are the ventricles equal in size? (4) Is there a septal defect? (5) Are the atrioventricular valves in a normal position? and (6) Is there any abnormality of the endocardium, myocardium, or pericardium? This article presents a practical approach to the detection of fetal cardiac anomalies using the four-chamber and outflow tract views. Examples of normal anatomy and cardiac pathology are provided as well as a listing of differential diagnoses that should be reviewed when certain abnormalities are visualized.

Sonographic diagnosis of peritoneal inclusion cysts

Peritoneal inclusion cysts have not received the attention they merit in the imaging literature. We present a series of peritoneal inclusion cysts and describe their sonographic features. Our findings lead us to encourage more conservative therapies. All seven patients in our series had pelvic pain and had undergone surgery previously. An ovary surrounded by septations and fluid was the most common finding by transvaginal sonography. Doppler examination showed low resistive flow in the septations. Conservative therapy was used in five cases with excellent results. We found that a confident diagnosis of peritoneal inclusion cysts is possible with ultrasonography. This diagnosis should encourage the use of more conservative therapy.

Hepatic ultrasonic changes in workers exposed to perchloroethylene

OBJECTIVE

To determine if subclinical hepatotoxicity is associated with exposure to perchloroethylene at concentrations commonly experienced in the workplace, and whether surveillance with serum hepatic transaminase activity underestimates such effects.

METHODS

Hepatic parenchymal echogenicity on ultrasonography and serum hepatic transaminase activity were compared in 29 community based dry cleaning operators exposed to perchloroethylene, and a control group of 29 non-exposed laundry workers. Perchloroethylene exposure was assessed by work history and air monitoring.

RESULTS

Mean hepatic transaminase activities were minimally increased in dry cleaners compared with laundry workers. Increased alanine aminotransferase activities, between 1.0 and 1.5 times the normal limits, were found in five of 27 (19%) dry cleaners compared with one of 26 (4%) laundry workers. In contrast, diffuse parenchymal changes in echogenicity, as determined by hepatic ultrasonography, were increased nearly twofold in dry cleaners, occurring in 18 of 27 (67%) dry cleaners compared with 10 of 26 (39%) laundry workers (P < 0.05), and were most strongly associated with increased perchloroethylene exposure in older dry to dry or wet transfer operations (odds ratio 4.2, 95% confidence interval 1.1-15.3). Mean eight hour time weighted average perchloroethylene exposure for dry cleaners was 16 ppm, which is less than the permissible exposure limit of 100 ppm in the United States.

CONCLUSIONS

It was concluded that mild to moderate hepatic parenchymal changes occur more frequently in workers exposed to perchloroethylene than in populations not exposed to chemical solvents, and that these effects are underestimated by serum hepatic transaminase activity.

Congenital uterine malformations

With the advent of newer imaging techniques, the radiologist is now able to make very precise and accurate diagnoses of congenital uterine malformations and their complications. Because these anomalies are associated with reproductive dysfunction, they are often discovered during an infertility evaluation. By imaging parallel to the long axis of the uterus, the external contour can be evaluated, obviating laparoscopy for differentiating septate from bicornuate uteri. Obstructed uterovaginal anomalies (e.g., hematometros, hematometrocolpos), an important complication of abnormal müllerian duct development, can occur at any time from the newborn period to adulthood. Determining the site of obstruction is imperative for planning the proper surgical approach. To understand these malformations better, we review the relevant embryology. The most widely accepted classification scheme is discussed in detail, with an emphasis on diagnosis, prognosis, and therapeutic options.

Pelvic lymphangioleiomyomatosis. Atypical precursor to pulmonary disease

A 22-year-old woman presented with left pelvic pain and mass. Ultrasonography confirmed a multilocular left adnexal mass containing cysts of varying sizes. The patient had no pulmonary symptoms at the time of presentation. The mass was surgically excised and pathologic diagnosis of lymphangioleiomyomatosis (LAM) was made. Subsequently, she developed hemoptysis and pleural effusion. High-resolution computed tomography of the chest showed findings consistent with LAM. Early diagnosis and treatment for LAM was possible in this atypical case.

Idiopathic polyhydramnios: association with fetal macrosomia

PURPOSE

To determine the relationship between idiopathic polyhydramnios and fetal macrosomia in the absence of maternal diabetes.

MATERIALS AND METHODS

Idiopathic polyhydramnios was studied with ultrasound (US) in 99 consecutive normal fetuses of nondiabetic women. Birth weights and estimated fetal weights were compared with those of postnatal and prenatal control groups, respectively.

RESULTS

The mean birth weight for the study (polyhydramnios) group was 3,771 g +/- 572 (standard deviation) compared with 3,476 g +/- 444 for the postnatal control group (P < .001). Birth weights in the 90th percentile or greater occurred in 28.2% of the study group versus 9.3% of the postnatal control group (P < .001) with a relative risk of 3.0 and a 95% confidence interval of 1.9, 4.9. The mean percentile of estimated fetal weight obtained with US was also significantly greater for the study group (79.3 +/- 23.7) than for the prenatal control group (51.5 +/- 32.7) (P < .001).

CONCLUSION

Idiopathic polyhydramnios is associated with large-for-gestational-age fetuses and macrosomia independent of maternal diabetes.

Infected aortic aneurysms: CT appearance

Three patients with infected (mycotic) aortic aneurysms were diagnosed primarily by CT. In two patients findings included the presence of a saccular aneurysm with an irregular lumen, perianeurysmal fluid, gas and/or hematoma, osteomyelitis in adjacent vertebral bodies, and disruption of intimal calcification. In one patient with sepsis there was rapid development of an aortic aneurysm. Computed tomography is of substantial benefit in the identification and characterization of infected aortic aneurysms. Certain features may strongly suggest the diagnosis without use of aortography.