Interrater agreement for sonographic stomach position classification in fetal diaphragmatic hernia across the North American Fetal Therapy Network.

OBJECTIVE: To evaluate inter-rater agreement for sonographic classification of stomach position (as a surrogate for liver herniation) in fetal left congenital diaphragmatic hernia (LCDH) among: (i) fetal medicine specialists from the North American Fetal Therapy Network (NAFTNet) centers within and without the fetal endoscopic tracheal occlusion (FETO) consortium and in comparison to an expert external reviewer (ER1); and (iii) among two expert ERs (ER1 and ER2). METHODS: Forty-eight physicians from 26 NAFTNet centers and 2 ERs were asked to assess 13 sonographic clips of isolated LCDH and classify stomach position as "intra-abdominal," "anterior left chest," "mid to posterior left chest," or "retro-cardiac" based on the classification published by Basta et al.8 Interrater agreement was assessed by determining proportion of stomach position ratings concordant amongst NAFTNet participants and ER1. Agreement for stomach position between ERs was calculated using kappa statistics. RESULTS: Agreement for stomach position was 69% (39%-85%; n = 19) and 54% (23%-92%; n = 29) among FETO and non-FETO NAFTNet participants, respectively, when compared to ER1. Most disagreement in stomach position was related to a discrepancy of one position. ERs were in agreement for stomach position in 5 of 13 cases (38.5%) and inter-rater agreement was highest for "anterior" stomach position. CONCLUSION: Interrater agreement for stomach position assessment in CDH was poor across NAFTNet and indeed amongst expert reviewers.

Outcomes for Prenatally Diagnosed Right Congenital Diaphragmatic Hernia.

BACKGROUND: Right congenital diaphragmatic hernia (CDH) occurs less frequently than left CDH. Therefore, prognostic indicators for right CDH are not as well studied as for left CDH. METHODS: A retrospective review from a single, tertiary referral center (from 1994 until July 2013) of patients with unilateral right CDH was conducted. Prenatal characteristics were evaluated and correlated with survival to discharge and need for extracorporeal membranous oxygen (ECMO). RESULTS: In total, 34 patients were identified. There were 12 postnatal deaths and 2 fetal demises (6%), representing an overall mortality of 41%. Six patients required ECMO. Nine patients underwent fetal intervention and were analyzed separately. For patients not undergoing fetal intervention, the survival rate was 52% and a higher mean (±SD) lung-to-head ratio (LHR) was associated with survival (1.1 ± 0.4 vs. 0.8 ± 0.2, p = 0.03). There were no deaths or need for ECMO in any patient with an LHR ≥1.0. Of the 9 patients who underwent fetal intervention, survival was 78% and only 1 patient required ECMO. Fetal intervention was primarily tracheal occlusion (n = 8). CONCLUSIONS: An LHR <1.0 is associated with worse survival for right CDH and may also reflect the need for ECMO.

Fetal stomach and gallbladder in contact with the bladder wall is a common ultrasound sign of stomach-down left congenital diaphragmatic hernia.

PURPOSE: The aim of this study was to identify sonographic (US) findings that can assist in prenatal diagnosis of stomach-down left congenital diaphragmatic hernia (CDH), specifically related to positioning of the abdominal contents including the stomach, bladder, and gallbladder. METHODS: All US examinations with a postnatally confirmed diagnosis of stomach-down left CDH over a 13-year period were retrospectively reviewed for abnormal position of the abdominal contents, including whether the fetal stomach was in contact with the urinary bladder. Normal fetuses that underwent comprehensive US surveys were similarly evaluated for comparison in a 2:1 ratio. RESULTS: Twenty-two fetuses with stomach-down left CDH were identified in a cohort of 278 fetuses with left CDH. In 15/22 (68.2%) cases of stomach-down left CDH, the bladder and stomach walls were in contact. Contact of the fetal gallbladder with the fetal bladder wall was also observed and was present even more commonly (17/22 cases [77.3%]). There was no case of either the stomach or gallbladder in contact with the bladder wall in the normal fetal cohort (n = 44). CONCLUSIONS: Recognition of the fetal stomach and/or gallbladder in contact with the bladder wall can help in the detection of stomach-down left CDH. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:8-13, 2017.

Spleen Behind the Heart Complicates Lung-to-Head Ratio Measurement in Left-Sided Congenital Diaphragmatic Hernia.

In fetuses with left-sided congenital diaphragmatic hernia, intrathoracic herniation of the spleen is a common occurrence. The herniated spleen can reside posterior to the left atrium of the heart in the right hemithorax and is increasingly differentiated from the lung with the use of newer sonographic equipment. Estimation of the neonatal prognosis relies on accurate measurement of fetal lung size, particularly with commonly used measurements such as the lung-to-head ratio. Here we describe how herniation of the spleen behind the heart can complicate measurement of the lung-to-head ratio on sonography and lead to overestimation, with implications for perinatal prognostication and management.

Fetal Stomach Position Predicts Neonatal Outcomes in Isolated Left-Sided Congenital Diaphragmatic Hernia.

INTRODUCTION: We sought to determine the relationship between the degree of stomach herniation by antenatal sonography and neonatal outcomes in fetuses with isolated left-sided congenital diaphragmatic hernia (CDH). MATERIALS AND METHODS: We retrospectively reviewed neonatal medical records and antenatal sonography of fetuses with isolated left CDH cared for at a single institution (2000-2012). Fetal stomach position was classified on sonography as follows: intra-abdominal, anterior left chest, mid-to-posterior left chest, or retrocardiac (right chest). RESULTS: Ninety fetuses were included with 70% surviving to neonatal discharge. Stomach position was intra-abdominal in 14% (n = 13), anterior left chest in 19% (n = 17), mid-to-posterior left chest in 41% (n = 37), and retrocardiac in 26% (n = 23). Increasingly abnormal stomach position was linearly associated with an increased odds of death (OR 4.8, 95% CI 2.1-10.9), extracorporeal membrane oxygenation (ECMO; OR 5.6, 95% CI 1.9-16.7), nonprimary diaphragmatic repair (OR 2.7, 95% CI 1.4-5.5), prolonged mechanical ventilation (OR 5.9, 95% CI 2.3-15.6), and prolonged respiratory support (OR 4.0, 95% CI 1.6-9.9). All fetuses with intra-abdominal stomach position survived without substantial respiratory morbidity or need for ECMO. DISCUSSION: Fetal stomach position is strongly associated with neonatal outcomes in isolated left CDH. This objective tool may allow for accurate prognostication in a variety of clinical settings.

Fetal ultrasound markers of severity predict resolution of pulmonary hypertension in congenital diaphragmatic hernia.

OBJECTIVE: Congenital diaphragmatic hernia (CDH) results in morbidity and death from lung hypoplasia and persistent pulmonary hypertension (PH). We sought to define the relationship between fetal ultrasound markers of severity in CDH and the time to resolution of neonatal PH. STUDY DESIGN: We conducted a retrospective study of fetuses with an antenatal ultrasound scan and left-sided CDH cared for at the University of California San Francisco (2002-2012). Fetal liver position was classified on ultrasound scan as abdominal (entire liver within the abdomen) or thoracic (any portion of the liver within the thorax). Fetal stomach position was classified from least to most aberrant: abdominal, anterior left chest, mid-posterior left chest, or retrocardiac (right chest). Lung-to-head ratio (LHR) was determined from available scans at 20-29 weeks of gestational age (GA). Routine neonatal echocardiograms were performed weekly for up to 6 weeks or until PH resolved or until discharge. PH was assessed by echocardiogram with the use of a hierarchy of ductus arteriosus level shunt, interventricular septal position, and tricuspid regurgitant jet velocity. Days to PH-free survival was defined as the age at which pulmonary artery pressure was estimated to be <2/3 systemic blood pressure. Cox proportional hazards models adjusted for GA at birth, era of birth, fetal surgery, and GA at ultrasound scan (LHR model only), with censoring at 100 days. RESULTS: Of 118 patients, the following fetal markers were available: LHR (n = 53), liver position (n = 112), and stomach position (n = 80). Fewer infants experienced resolved PH if they had LHR <1 (P = .006), thoracic liver position (P = .001), or more aberrant stomach position (P < .001). There was also a decreased rate of resolution of PH in infants with LHR <1 (hazard ratio, 0.30; P = .007), thoracic liver position (hazard ratio, 0.38; P < .001), and more aberrant stomach position (hazard ratios, 0.28 [P = .002]; 0.1 [P < .001]; and 0.07 [P < .001]). CONCLUSION: Fetal ultrasound markers of CDH severity are predictive not only of death but also of significant morbidity. LHR <1, thoracic liver, and aberrant stomach position are associated with delayed time to resolution of PH in infants with CDH and may be used to identify fetuses at high risk of persistent PH.

Testicular malakoplakia: a rare sonographic mimic of malignancy.

Testicular malakoplakia is a rare, benign condition that most often occurs in an immunocompromised patient with chronic infection. Its occurrence is acute, with pain and testicular enlargement. Sonography is commonly performed to evaluate the patient for epididymitis or torsion. The appearance of testicular malakoplakia on sonography examination has only rarely been described, making its diagnosis challenging. Because its appearance overlaps with testicular neoplasm and infection, it should be considered when making a differential diagnosis of a diffuse testicular abnormality in the appropriate clinical setting.

The fetal urinoma revisited.

The fetal urinoma is a rare but important diagnosis, as it indicates substantial underlying obstruction with implications for the functionality of the affected kidney. This case series describes a single center's experience with the diagnosis and management of fetal urinomas. All 25 cases were diagnosed or referred to our medical center over an 11-year period. Most cases were secondary to either posterior urethral valves or ureteropelvic junction obstruction. Fetal interventions, including percutaneous drainage of the urinoma and cystoscopic alleviation of bladder outlet obstruction, were performed in 4 cases.

Impact of new society of radiologists in ultrasound early first-trimester diagnostic criteria for nonviable pregnancy.

OBJECTIVES: New early first-trimester diagnostic criteria for nonviable pregnancy recommended by the Society of Radiologists in Ultrasound via a multispecialty consensus panel extended the diagnostic size criteria of crown-rump length from 5 to 7 mm for embryos without a heartbeat and mean sac diameter from 16 to 25 mm for "empty" sacs. Our study assessed the potential impact of the new criteria on the number of additional follow-up sonograms these changes would engender. METHODS: A retrospective study of all first-trimester sonograms in women with first trimester bleeding from 1999 to 2008 was conducted. Everyone included in the study had a visible gestational sac in the uterus. There were no pregnancies of unknown location or ectopic pregnancies included in this study cohort. Pregnancy of unknown location was used to describe cases in which there were no signs of pregnancy inside or outside the uterus on transvaginal sonography despite a positive pregnancy test result. A total of 1013 patients met the inclusion criteria. RESULTS: Seven hundred fifty-two patients (74%) had identifiable embryos, and 261 (26%) did not. Of those with an identifiable embryo, 286 (38%) had no detectable embryonic cardiac activity. The breakdown of crown-rump lengths in this group was as follows: 100 measuring less than 5 mm, 36 measuring 5 to 7 mm, and 150 measuring 7 mm or greater. The breakdown of mean sac diameters in those without a visible embryo was as follows: 120 measuring less than 16 mm, 90 measuring 16 to 25 mm, and 51 measuring 25 mm or greater. CONCLUSIONS: When diagnosing a failed pregnancy, there can be no room for error. Only 126 of 1013 early pregnancies threatening to abort (12%) fell into the more conservative zones defined by the new compared to the former size criteria (crown-rump length, 5-7 mm; mean sac diameter, 16-25 mm). Therefore, the potential impact of the new guidelines on follow-up sonograms does not appear inordinate.

The grand unifying theory of bright echoes in the fetal and neonatal brain.

The purpose of this presentation is to illustrate that the high-amplitude reflecting structures in the fetal and neonatal brain can be explained by the echogenicity of their leptomeningeal coverings or leptomeningeal origins. The leptomeninges, especially the pia mater, constitute the "grand unifying theory of bright reflectors" in the fetal and neonatal brain. Images from fetal and neonatal sonograms were selected to illustrate the objectives above.

Value of "minimum menstrual age" in determining early pregnancy failure.

OBJECTIVES: The purposes of this study were to assess a discriminatory "minimum menstrual age" (28 days + number of days elapsed between the first positive pregnancy test result and sonogram) for the diagnosis of early pregnancy failure when no embryonic/fetal heartbeat is seen and to compare minimum menstrual age dating with last menstrual period and sonographic dating. METHODS: We conducted a retrospective study of 338 initial first-trimester sonographic examinations among women with suspected early pregnancy failure. A minimum menstrual age for each was calculated, and pregnancy outcomes were assessed. The predictive value of the minimum menstrual age for the pregnancy outcome was assessed at both 42 and 49 days and compared to that of dating by the last menstrual period and sonography. RESULTS: Among a study cohort of 338 patients, the average gestational age calculated by the last menstrual period was 53 days; by sonography, it was 50 days; and by the minimum menstrual age, it was 35 days (P < .01). All cases in which there was no sonographically detectable embryonic heartbeat above a minimum menstrual age of 42 days resulted in pregnancy failure. CONCLUSIONS: The minimum menstrual age is a conservative estimate of the gestational age, with an estimated positive predictive value of 100% for early pregnancy failure when no embryonic heartbeat is seen after 42 days. The minimum menstrual age can be combined with other existing diagnostic clues to predict early pregnancy failure with greater accuracy.

Sonographic anatomy of the gastrohepatic ligament.

OBJECTIVE: The purpose of this presentation is to illustrate anatomic and pathologic features of the gastrohepatic ligament (GHL) and to show its usefulness for precise localization of abnormalities, particularly in relation to the lesser peritoneal cavity and diseases occurring within the confines of the ligament itself. METHODS: Cases were selected that illustrate the objectives above. RESULTS: Illustrations show various anatomic and pathologic features meant to enhance interpretation of left upper quadrant sonograms. CONCLUSIONS: Illustrations seen in the sonographic literature vaguely interpret the relationships of the GHL. Misunderstanding has led not only to improper nomenclature but also to the use of inappropriate indicators of lesser omental diseases. With a clear understanding of the anatomy of the GHL and its use as a pivotal marker for structures around and within it, one can avoid these pitfalls and better evaluate adult and pediatric lesser omental anatomy.

The yolk stalk sign: evidence of death in small embryos without heartbeats.

OBJECTIVE: The purpose of this study was to assess the positive predictive value for confirming early embryonic death in the clinical sonographic scenario wherein an embryo is identified without a visible heartbeat; the embryonic crown-rump length (CRL) is 5 mm or less; and the embryo is not immediately adjacent to the yolk sac. METHODS: A retrospective study of 882 first-trimester sonograms was performed among women who had an intrauterine pregnancy of uncertain viability based on 1 or more sonographic findings (eg, no visible heartbeat in an embryo with a CRL of < or =5 mm). Eight hundred six cases met the inclusion criteria. RESULTS: Among the cohort of 806 cases, 520 (64.5%) had an identifiable embryo. One hundred fifty-nine of these embryos had no demonstrable heartbeat and a CRL of 5 mm or less. The CRLs of these embryos ranged from 1.7 to 5.4 mm. This cohort's sonograms were reviewed to determine whether there was a separation between the embryo and yolk sac. Twenty-one cases were discovered. Recall that as a retrospective study, no specific effort was made to show this finding. Thus, a computation of the sensitivity of this finding would result in an underestimate of indeterminate magnitude. All of these cases were subsequently proven to be failed pregnancies. CONCLUSIONS: The positive predictive value of the "yolk stalk sign" in determining early pregnancy failure for an embryo with a CRL of 5 mm or less and no visible heartbeat was 100% in this cohort.

Supratentorial abnormalities in the Chiari II malformation, IV: the too-far-back ventricle.

OBJECTIVE: The sonographic diagnosis of fetal myelomeningocele (MMC) has improved mainly because the diagnostic focus has shifted from observation of the spinal abnormality to observation of cranial abnormalities. We describe an abnormality in the position of the occipital horn in fetuses with MMC. The occipital horn appears to be too posterior in location when compared to healthy fetuses. METHODS: We searched for all cases in which fetal MMC was sonographically detected from 1999 to 2009. Random controls from normal pregnancies were identified. We then measured the shortest distance of the edge of the occipital horn to the occipital bone in fetuses with MMC compared to healthy fetuses. Only fetuses with MMC who had normal-size ventricles were included. RESULTS: A total of 91 fetuses with MMC were identified. Twenty-six fetuses had a normal ventricle size. The gestational age range in this cohort was 18 weeks 5 days to 30 weeks 0 days. The comparison group of 39 healthy fetuses all had normal ventricles and had a gestational age range of 18 weeks 3 days to 35 weeks 2 days. After adjusting for gestational age, the statistical analysis showed that fetuses with MMC had significantly shorter measured distances from the posterior edge of the occipital horn to the occipital bone than healthy fetuses (P = .003). CONCLUSIONS: The occipital horn both appears to be and measures closer to the occipital bone in fetuses with MMC compared to healthy fetuses.

Further observations on the empty "amnion sign".

OBJECTIVE: To assess the positive predictive value of the empty "amnion sign" (visualization of an amnion without concomitant visualization of an embryo) for the diagnosis of early pregnancy failure. METHODS: Retrospective study of 882 1st trimester sonographic examinations with abnormal findings among women who were threatening to abort. Eight hundred six met the inclusion criteria. RESULTS: In the study cohort 286 (35.5%) had no identifiable embryo and 71 of those without an identifiable embryo had a visible amnion (24.8%). The breakdown of the mean sac diameter of the study cohort was as follows: those measuring less than 16 mm (n = 16); those measuring 16-20 mm (n = 20); those measuring 21 mm or more (n = 35). Sixty-eight of the 71 patients had adequate follow-up. Pregnancy failure was confirmed in all 68 patients (positive predictive value = 100%). CONCLUSIONS: The data from this study indicate that visualization of an amnion without concomitant visualization of an embryo (the empty "amnion sign") confirms pregnancy failure regardless of the mean sac diameter and with a sufficiently high positive predictive value to make a definitive diagnosis.

The expanded amnion sign: evidence of early embryonic death.

OBJECTIVE: The purpose of this study was to assess the positive predictive value for confirming early embryonic death in the clinical scenario wherein an embryo is identified without a visible heartbeat, but the embryonic crown-rump length (CRL) is 5 mm or less. METHODS: We conducted a retrospective study of 882 first-trimester sonograms with abnormal findings among women who were threatening to abort. Eight hundred six met the inclusion criteria. RESULTS: Among the cohort of 806 cases, 520 (64.5%) had an identifiable embryo, and 255 of those with an identifiable embryo had a visible amnion (49.0%). One hundred sixteen of the 255 with a visible amnion and an identifiable embryo without a heartbeat had a CRL that measured 5 mm or less (45.5%). The CRL of these embryos ranged from 1.7 to 5.4 mm (ie, when rounded to the nearest millimeter, these embryos would be 5 mm) with the breakdown as follows: those measuring less than or equal to 3.4 mm (n = 28), those measuring 3.5 to 4.4 mm (n = 45), and those measuring 4.5 to 5.4 mm (n = 43). Eight of these 116 patients did not have any documented follow-up. In the remaining 108 patients, pregnancy failure was confirmed. CONCLUSIONS: We conclude that any embryo that is surrounded by an amnion and that also lacks a heartbeat has unfortunately but definitively died. This is equally true for embryos measuring less than 5 mm in CRL.

Supratentorial abnormalities in the Chiari II malformation, II: tectal morphologic changes.

OBJECTIVE: The sonographic diagnosis of fetal myelomeningocele has improved mainly because the diagnostic focus has shifted from observation of spinal manifestations to observation of cranial abnormalities. Intracranial diagnostic criteria rely on abnormalities in the posterior fossa. We describe abnormalities in tectal morphologic characteristics that, although well described on magnetic resonance imaging, have received little attention in the sonographic literature. This study analyzed the frequency of this observation and technical aspects that improve its visualization. METHODS: From a database of obstetric sonograms, we identified all cases of sonographically detected myelomeningocele. The search covered the years 1999 to 2007. We retrospectively reviewed the fetal intracranial findings with special attention to elongation or "beaking" of the tectum. RESULTS: A total of 89 fetuses were identified. The mean and median gestational ages were 22 weeks 4 days and 22 weeks 2 days, respectively. Of the 89 cases, 59 (66%) had an abnormal tectal shape. The abnormality was seen in 77% of cases judged to be suboptimally visualized and 62% of cases with good visualization. Tectal abnormalities were seen equally well in fetuses before and after 24 weeks. Finally, tectal abnormalities were seen more frequently as the severity of posterior fossa findings increased. CONCLUSIONS: Tectal morphologic alteration is a common supratentorial feature of the Chiari II malformation on prenatal sonography both before and after 24 weeks' gestation. Its frequency increases with the severity of posterior fossa abnormalities. Therefore, it may be useful as a supratentorial indicator of both the presence and, potentially, the severity of the Chiari II malformation.