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.

Reliability of the lung-to-head ratio as a predictor of outcome in fetuses with isolated left congenital diaphragmatic hernia at gestation outside 24-26 weeks.

OBJECTIVE: The purpose of this study was to investigate the relationship between lung-to-head ratio (LHR) and gestational age (GA) in fetuses with isolated left congenital diaphragmatic hernia and to determine the applicability and reliability of LHR to predict postnatal outcome beyond 24-26 weeks of gestation. STUDY DESIGN: The institutional review board approved this retrospective review of the University of California, San Francisco, Fetal Treatment Center database for cases with left congenital diaphragmatic hernia who were referred between March 1995 and June 2004. LHR was determined at the initial evaluation. One hundred seven live-born fetuses at 20-34 weeks of gestation (excluding cases that were lost to follow-up, with factors that potentially could influence the LHR measurement or postnatal outcome, or that were terminated electively). RESULTS: The median GA at LHR measurement was 25.6 weeks; the median LHR was 1.01; the median GA at birth was 37.7 weeks; and the overall survival rate was 59% (64/107). The median LHR of nonsurvivors was significantly lower than that of survivors, but neither GA at LHR measurement nor at delivery was significantly different between the groups. Multiple logistic regression analysis confirmed LHR to be an independent predictor of postnatal survival, and receiver-operator characteristic curve analysis demonstrated that an LHR of > or = 0.97 has the highest performance in predicting postnatal survival. When fetuses were grouped by GA at initial LHR measurement to determine reliability of LHR, specifically with respect to GA, in the 26-34 and 24-26 weeks of gestation groups, median LHR of survivors was significantly higher than that of nonsurvivors, and receiver-operator characteristic curve analysis confirmed LHR to be a reliable predictor of postnatal survival. However, for fetuses at 20-24 weeks of gestation, there was a trend toward a higher LHR in survivors, although this did not reach statistical significance. CONCLUSION: A significant positive linear relationship exists between LHR and GA at the time of measurement, such that LHR reliably predicts postnatal survival in fetuses with left congenital diaphragmatic hernia at 24-34 weeks of gestation and less reliable at 20-24 weeks. However, given the limitations of a retrospective, cross-sectional study, further prospective longitudinal studies that will investigate the change of LHR with GA and its association with fetal outcome are necessary.

Fetal cerebellar hemorrhage in parvovirus-associated non-immune hydrops fetalis.

We report two cases of fetal cerebellar hemorrhage in the setting of parvovirus-associated hydrops fetalis and fetal blood transfusion. In both cases, the cerebellar hemorrhage was diagnosed by fetal magnetic resonance imaging after intrauterine blood transfusion. To our knowledge, this is the first report of fetal cerebellar hemorrhage in the setting of parvovirus-associated hydrops fetalis, and may be the result of cerebrovascular changes both during and after the transfusion.

Detection of occult melanoma by preoperative positron emission tomography-computed tomography and intraoperative ultrasonography.

BACKGROUND: 18F-Fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) has become a common imaging modality for detecting metastatic melanoma. However, the identification of lesions intraoperatively can be difficult. OBJECTIVE/METHODS: We describe an innovative multimodality approach to tumor localization using preoperative PET-CT and intraoperative ultrasonography and describe cases in which this technique was used. RESULTS: The use of these two modalities together enabled resection of multiple occult metastatic lesions in the patients presented. CONCLUSION: The use of this multimodality approach will be important in ensuring that all known metastatic disease sites are resected and represents an important concept in the setting of metastatic melanoma resection.

Evaluation of diffuse liver steatosis by ultrasound, computed tomography, and magnetic resonance imaging: which modality is best?

PURPOSE: To compare ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) determination of diffuse liver steatosis. MATERIALS AND METHODS: Quantification of liver steatosis on ultrasound, CT, and MRI was correlated with histopathology in 67 patients. RESULTS: Opposed-phase MRI demonstrated the highest correlation with steatosis (0.68 and 0.69, P<.01; intraclass correlation coefficient, 0.93). Spearman's correlation (and intraclass correlation) coefficients were lowest for ultrasound [0.54, 0.33 (0.40)] and enhanced CT [0.33, 0.39 (0.97)]. CONCLUSION: Opposed-phase MRI demonstrated best overall performance for determining steatosis.

Columns of the fornix, not to be mistaken for the cavum septi pellucidi on prenatal sonography.

OBJECTIVE: Visualization of the cavum septi pellucidi (CSP) is considered an integral part of the prenatal second-and third-trimester sonographic evaluations of the fetal neural axis. We have noted that another anatomic structure, the columns of the fornix, can be mistaken for the CSP and result in the missed diagnosis of agenesis of the corpus callosum. METHODS: We describe a case in which the columns of the fornix were misinterpreted as representing the CSP during a sonographic evaluation at 18 weeks' gestation. After a follow-up sonogram at 35 weeks, agenesis of the corpus callosum was detected. A retrospective evaluation of the prevalence of forniceal columns was then performed in 100 consecutive sonograms of pregnancies between 18 and 24 weeks' gestation. A prospective study was then performed in 20 patients to determine the prevalence of visualization of the columns of the fornix. RESULTS: In 86 of 100 patients, the columns of the fornix were retrospectively identified as discrete and separate structures from the CSP. When additional views were obtained prospectively in the forebrain, the fornix could be identified in all 20 patients. CONCLUSIONS: The columns of the fornix may simulate the appearance of the CSP on second- and third-trimester sonograms. The distinction between these structures can be made because the columns of the fornix will show a linear reflection (3 lines) at their interface, whereas the CSP will appear as a fluid-filled triangular or rectangular fluid-filled space without a central line.

Sonographic detection of gallbladder duplication: two cases discovered in utero.

OBJECTIVE: To report the in utero diagnosis of a duplicated gallbladder. METHODS: Obstetric sonography was performed at 2 separate referral centers. A comprehensive level 11 examination was performed at each center. RESULTS: In both cases, a duplicated gallbladder was detected in utero without the presence of other anatomic abnormalities. CONCLUSIONS: Gallbladder duplication, although uncommon, should be considered when an additional cystic structure is seen in the right upper quadrant. Recognition of the presence of a duplicated gallbladder, a relatively benign condition, prevents invoking a more serious diagnosis, such as a choledochal or duodenal duplication cyst.

Sonographic evaluation of liver nodularity: Inspection of deep versus superficial surfaces of the liver.

PURPOSE: We determined the diagnostic performance of assessing the nodularity of deep versus superficial surfaces of the liver as a predictor of cirrhosis. METHODS: One sonologist retrospectively reviewed the sonograms of 100 patients at risk for cirrhosis based on clinical data and laboratory tests. A second sonologist reviewed the sonograms of a subset of 25 patients to assess for inter-reader variability, while the first sonologist re-reviewed the sonograms of a different subset of 25 patients for intrareader variability. Sonograms of all patients were obtained with standard sector- or curved-array transducers. Biopsy confirmation of cirrhosis was used as the standard for diagnostic accuracy. RESULTS: Fifty of the 100 patients had a pathologic diagnosis of cirrhosis. The sensitivity of inspection of the deep surface versus the superficial surface was 86% versus 53% (p = 0.0003), respectively. Sensitivity was not dependent on pathologic type. Intrareader agreement was better for deep than for superficial surface observations. The overall inter-reader agreement was fair and comparable for both deep and superficial surface methods. CONCLUSIONS: The sensitivity for detecting cirrhosis based on surface nodularity is greater for deep than for superficial surface observations. As the prevalence of disease increases, the accuracy of assessment of the deep surface in predicting cirrhosis increases.

Successful fetal intervention for congenital high airway obstruction syndrome.

INTRODUCTION: Complete congenital high airway obstruction syndrome (CHAOS) usually leads to stillbirth or death within minutes of delivery. We describe the management and long-term follow-up of a baby with a prenatally diagnosed airway obstruction. CASE: Because of progressive hydrops fetalis, massive ascites and everted diaphragms due to CHAOS in a fetus at 24 weeks of gestation, a fetal tracheostomy was performed. Persistent fetal bradycardia at the time of the fetal procedure led to delivery of the infant. Adequate oxygenation and ventilation were attained using relatively low oxygen concentrations and low ventilatory pressures. Plain radiographs demonstrated that the lungs were large and the ribs thin. The infant has a permanent tracheostomy, required continuous assisted ventilation for several months and assisted ventilation at night at home for 3 years. At 4 years of age, he has no speech, all feedings are by gastrostomy, and developmentally he is mildly to moderately delayed. CONCLUSION: Laryngeal atresia produced over-distended lungs and hydrops. Precise prenatal imaging and fetal surgical strategies may allow the survival of affected fetuses.

Intraventricular hemorrhage in term neonates caused by sinovenous thrombosis.

The cause of intraventricular hemorrhage in term neonates is poorly understood. Among 29 neonates of at least 36 weeks' gestation with intraventricular hemorrhage, 9 (31%) had cerebral sinovenous thrombosis. Of the 26 neonates who underwent computed tomography or magnetic resonance studies, those with thalamic hemorrhage were more likely to have sinovenous thrombosis than those without thalamic involvement (4/5 vs 5/21, p = 0.03). Term neonates with intraventricular hemorrhage should undergo neuroimaging to evaluate the presence of sinovenous thrombosis. Ann Neurol 2003