Successful Postnatal Tracheobronchoplasty for Unilateral Congenital High Airway Obstruction Syndrome due to Mainstem Bronchial Atresia.

Introduction: Unilateral congenital high airway obstruction syndrome (CHAOS) is caused by a complete obstruction of a mainstem bronchus with resulting hyperinflation and accelerated growth of one lung, severe mediastinal shift, and hydrops. Spontaneous perforation of the atresia has been observed in CHAOS which allows hydrops to resolve but hyperinflation, mediastinal shift and a critical airway obstruction persists as the perforation is usually pinhole-sized.

Case Presentation: We present a case of unilateral CHAOS presenting at 26 2/7 weeks with observed-to-expected total lung volume (O/E TLV) of 203% with spontaneous perforation occurring at 28 weeks with resolution of hydrops but persistence of hyperinflation and mediastinal shift with an O/E TLV of 60.

Second trimester placenta percreta presenting as acute abdomen.

Diagnosing placenta percreta can be difficult. We describe a 41-year-old woman presenting at 21 weeks' gestation with intraabdominal bleeding and no signs of placental abnormality on ultrasound. The disagreement between results of the ultrasound and magnetic resonance imaging made definitive diagnosis difficult.

Forests, fields, and the edge of sustainability at the ancient Maya city of Tikal.

Tikal has long been viewed as one of the leading polities of the ancient Maya realm, yet how the city was able to maintain its substantial population in the midst of a tropical forest environment has been a topic of unresolved debate among researchers for decades. We present ecological, paleoethnobotanical, hydraulic, remote sensing, edaphic, and isotopic evidence that reveals how the Late Classic Maya at Tikal practiced intensive forms of agriculture (including irrigation, terrace construction, arboriculture, household gardens, and short fallow swidden) coupled with carefully controlled agroforestry and a complex system of water retention and redistribution. Empirical evidence is presented to demonstrate that this assiduously managed anthropogenic ecosystem of the Classic period Maya was a landscape optimized in a way that provided sustenance to a relatively large population in a preindustrial, low-density urban community.

Model of magnetically guided fetal cardiac intervention: potential to avoid direct cardiac puncture.

Objective: Fetal cardiac interventions are performed via direct cardiac puncture and are associated with significant fetal morbidity. The feasibility of utilizing magnetic navigation to maneuver a guide wire and balloon across a fetal aortic valve without direct cardiac puncture is tested.

Methods: A fetal heart model was manufactured and placed in a catheterization laboratory equipped with magnetic navigation.

MRI calculation of lung volumes to predict outcome in fetuses with genitourinary abnormalities.

Objective: The purpose of our study was to evaluate MRI total lung volumes (TLV) for predicting outcome in fetuses with genitourinary abnormalities and to compare lung volumes with the presence or absence of oligohydramnios.

Materials And Methods: Fetuses with genitourinary abnormalities underwent blinded retrospective calculation of TLV. Distribution of the TLV-gestational age ratios for survivors and nonsurvivors were compared using the Wilcoxon's rank sum test.

MRI of fetal genitourinary anomalies.

Objective: The objective of our study was to show examples of fetal MRI evaluations of congenital genitourinary anomalies and to review the embryology in relation to the MRI findings.

Conclusion: MRI was performed on 35 pregnant women with sonographic findings that suggested that their fetuses had genitourinary anomalies. Oligohydramnios or anhydramnios was identified in 22 of 35 women and did not hinder visualization of anomalies.

Fetal central nervous system biometry on MR imaging.

Objective: We sought to compare the biometry of the fetal head on MR imaging with sonographic measurements in fetuses with and without suspected central nervous system abnormalities.

Materials And Methods: Blinded retrospective measurements of biparietal diameter, head circumference, and cerebellar width obtained on MR imaging were assigned a gestational age on the basis of median sonographic measurements and compared with sonographic and clinical assignment of gestational age in fetuses with no central nervous system abnormalities. In fetuses with central nervous system abnormalities, the same MR measurements were compared with sonographic measurements obtained within 1 week.

Second-opinion magnetic resonance imaging for suspected fetal central nervous system abnormalities.

Objective: The purpose of this study was to evaluate the relationship of magnetic resonance imaging and gestational age in the setting of fetuses with suspected abnormalities of the central nervous system that were detected by ultrasound scanning.

Study Design: Multiplanar magnetic resonance studies were performed in fetuses with suspected central nervous system abnormalities on ultrasound scanning. Magnetic resonance imaging was evaluated for its ability to provide additional information, change the diagnosis, or impact obstetric treatment.

Fetal central nervous system ventricle and cisterna magna measurements by magnetic resonance imaging.

Objective: Our purpose was to evaluate the ventricular atria and cisterna magna in fetuses with and without suspected central nervous system (CNS) anomalies by magnetic resonance (MR).

Study Design: Measurements of the right and left ventricular atria and cisterna magna were obtained by MR in two groups: those with and without CNS anomalies. Published mean ultrasound measurements of the far field atrium were compared with MR.