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Danzer E, Hubbard AM, Hedrick HL, Johnson MP, Wilson RD, Howell LJ, Flake AW, Adzick NS. Diagnosis and characterization of fetal sacrococcygeal teratoma with prenatal MRI. AJR Am J Roentgenol 2006; 187:W350-6. [PMID: 16985105 DOI: 10.2214/ajr.05.0152] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIVE The purpose of this study was to determine whether prenatal MRI provides additional information about fetal sacrococcygeal teratoma compared with prenatal sonography. MATERIALS AND METHODS Twenty-two pregnant women with fetal sacrococcygeal teratoma underwent prenatal MRI (mean gestational age, 23 weeks). The size, location, mass characteristics, and compressive effects of the tumors were determined and correlated with sonography and postnatal findings. RESULTS Based on the MRI findings, the following American Academy of Pediatrics, Surgical Section classifications were assigned: type I in six patients, type II in 12, and type III in four. No type IV tumors were found. The sacrococcygeal teratoma appeared entirely cystic in five fetuses, microcystic in one, mixed cystic and solid in 12, and solid in four. The diagnosis of sacrococcygeal teratoma was accurate in all cases assessed at our center using both MRI and sonography. Two additional patients initially referred with the diagnosis of sacrococcygeal teratoma had a different diagnosis at reevaluation at our institution (healthy, n = 1; myelomeningocele, n = 1). MRI was superior to sonography for detecting displacement of the colon (n = 11), urinary tract dilatation (n = 9), hip dislocation (n = 4), intraspinal extension (n = 2), and vaginal dilation (n = 1). In fetuses with sacrococcygeal teratoma types II and III, MRI better showed the cephalic extent of the tumor compared with sonography. MRI findings were confirmed at surgery or autopsy in all patients. Three fetuses with high output cardiac physiology underwent open fetal resection of the tumor at 21-, 24-, and 26-weeks' gestational age with two surviving. CONCLUSION Our results show that ultrafast fetal MRI is a useful adjunct to the prenatal evaluation of fetal sacrococcygeal teratoma. Compared with sonography, MRI more accurately characterized the intrapelvic and abdominal extent of the tumors and provided more information on compression of adjacent organs. The additional anatomic resolution provided by MRI resulted in more accurate prenatal counseling and improved preoperative planning for surgical resection.
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Danzer E, Johnson MP, Bebbington M, Simon EM, Wilson RD, Bilaniuk LT, Sutton LN, Adzick NS. Fetal Head Biometry Assessed by Fetal Magnetic Resonance Imaging following in utero Myelomeningocele Repair. Fetal Diagn Ther 2006; 22:1-6. [PMID: 17003546 DOI: 10.1159/000095833] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2005] [Accepted: 01/21/2006] [Indexed: 12/28/2022]
Abstract
OBJECTIVE To examine the impact of fetal myelomeningocele (MMC) repair on fetal head biometry and cerebrospinal fluid (CSF) spaces assessed by magnetic resonance imaging (MR) studies. STUDY DESIGN Axial measurements of intracranial structures were taken at defined anatomical landmarks. Pre- and postnatal head biometry data and CSF spaces obtained from in utero repaired MMC fetuses (n = 22) were compared to the pre- and postnatal measurements of MMC patients that underwent standard neurosurgical MMC repair after birth (n = 16) and a cohort of age-matched control patients (prenatal, n = 52; postnatal, n = 9). RESULTS In fetuses with MMC, initial MR scans showed an almost complete absence of supratentorial and posterior fossa CSF spaces. No differences in postnatal CSF spaces were found between controls and prenatally repaired MMC newborns. In fetuses with postnatal MMC repair, CSF spaces remained significantly reduced (p < 0.0001). The mean ventricular diameter (VD) increase in the postnatal repaired MMC group was significantly higher compared to the mean percentage of VD increase in the fetal repaired MMC group (6.4 vs. 4.2 mm; p = 0.02). Pre- and postnatal brain thickness measurements were significantly reduced in both MMC populations compared to age-matched normal values (p < 0.0001). In contrast to postnatally repaired patients, in utero repair fetuses showed significant reversal of hindbrain herniation and normalization of the posterior fossa CSF spaces. CONCLUSION Mid-gestational repair of MMC promotes normalization of extra-axial CSF spaces. Due to progressive ventriculomegaly, brain thickness remains decreased in both prenatal repaired and age-matched non-repaired MMC patients when compared to age-matched normal values. Restoration of CSF volume in the posterior fossa after in utero repair is indicative of reversal of hindbrain herniation.
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Moses EK, Fitzpatrick E, Freed KA, Dyer TD, Forrest S, Elliott K, Johnson MP, Blangero J, Brennecke SP. Objective prioritization of positional candidate genes at a quantitative trait locus for pre-eclampsia on 2q22. Mol Hum Reprod 2006; 12:505-12. [PMID: 16809377 DOI: 10.1093/molehr/gal056] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Pre-eclampsia/eclampsia (PE/E) is a common, serious medical disorder of human pregnancy. Familial association of PE/E has been recognized for decades, but the genetics are complex and poorly understood. In an attempt to identify PE/E susceptibility genes, we embarked on a positional cloning strategy using 34 Australian and New Zealand PE/E pedigrees. An initial 10-cM resolution genome scan revealed a putative susceptibility locus spanning a broad region on chromosome 2 that overlaps an independently determined linkage signal seen in Icelandic PE pedigrees. Subsequent fine mapping using 25 additional short tandem repeat (STR) markers in this region and non-parametric multipoint linkage analysis did not change the overall position. Under a strict diagnosis of PE, we obtained significant evidence of linkage on 2q with a peak log-of-odds ratio score (LOD) of 3.43 near marker D2S151 at 155 cM. To prioritize positional candidate genes at the 2q locus for detailed analysis, we applied an objective prioritization strategy that integrates quantitative bioinformatics, assessment of differential gene expression and association analysis of single-nucleotide polymorphisms (SNPs). Highest priority was assigned to the activin receptor gene ACVR2. This gene also showed >10-fold differential gene expression in human decidual tissue from normotensive and PE individuals. We genotyped five known SNPs in this gene in our pedigrees and performed tests for association and linkage disequilibrium. One SNP (rs1424954) showed strong preliminary evidence of association with PE (P = 0.007), whereas two others (rs1364658 and rs1895694) exhibited nominal evidence (P < 0.05). Haplotype analysis revealed no additional association information. There was evidence of weak linkage disequilibrium among these SNPs. The highest observed LD occurred between the two strongest associated SNPs, suggesting that the observed signals may be the signature of an observed functional variant.
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Bebbington M, Wilson RD, Johnson MP. Detection of congenital heart disease in the first trimester of pregnancy. PROGRESS IN PEDIATRIC CARDIOLOGY 2006. [DOI: 10.1016/j.ppedcard.2006.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Howell LJ, Johnson MP, Scott Adzick N. Creating a state-of-the-art center for fetal diagnosis and treatment: Importance of a multidisciplinary approach. PROGRESS IN PEDIATRIC CARDIOLOGY 2006. [DOI: 10.1016/j.ppedcard.2006.01.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Wilson RD, Hedrick HL, Liechty KW, Flake AW, Johnson MP, Bebbington M, Adzick NS. Cystic adenomatoid malformation of the lung: review of genetics, prenatal diagnosis, and in utero treatment. Am J Med Genet A 2006; 140:151-5. [PMID: 16353256 DOI: 10.1002/ajmg.a.31031] [Citation(s) in RCA: 138] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Prenatal identification of lung abnormalities has increased with prenatal surveillance. Treatment usually requires serial ultrasound observation but in rare situations in utero therapy may be required for fetal survival. We review the genetics, prenatal evaluation, and treatment of lung abnormalities with congenital cystic adenomatoid malformation (CCAM). Other lung lesions, bronchopulmonary sequestration (BPS), hybrid lesions involving both malformations, congenital lobar emphysema (CLE), are briefly included as differential diagnosis options. Outcome of fetuses identified to have CCAM lung abnormalities resulting in fetal hydrops and having in utero therapy (thoracoamniotic shunting, fetal thoracotomy, EXIT delivery) are discussed. In the appropriate situation, this maternal fetal surgery approach for CCAM is life-saving for the affected fetus with acceptable maternal morbidity risks in the present and future pregnancies.
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Chen SC, Simon EM, Haselgrove JC, Bilaniuk LT, Sutton LN, Johnson MP, Shera DM, Zimmerman RA. Fetal Posterior Fossa Volume: Assessment with MR Imaging. Radiology 2006; 238:997-1003. [PMID: 16505396 DOI: 10.1148/radiol.2383041283] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To retrospectively determine the relationship between posterior fossa volume (PFV) and estimated gestational age (EGA) and/or femur length (FL) during pregnancy for the purpose of developing a normal growth curve. MATERIALS AND METHODS Advance institutional review board approval was obtained for this HIPAA-compliant study, and the need for parent informed consent was waived. A cross-sectional retrospective study was performed to measure PFV on in vivo magnetic resonance (MR) images obtained in 76 fetuses of 18-36 weeks gestation who had a morphologically normal CNS. Because this was a retrospective series, MR imaging techniques varied slightly, but all fetuses underwent imaging at contiguous 3-5-mm intervals in at least two orthogonal planes, with repetition time msec/echo time msec, 5-12/62-95; number of signals acquired, one; flip angle, 150 degrees -180 degrees; and matrix, 128-192 x 256. Posterior fossa areas were manually traced on half-Fourier rapid acquisition with relaxation enhancement in utero fetal MR images by one observer. PFVs were then calculated by manually summing areas from the contiguous sections and multiplying the total area by the section thickness. An average PFV (APFV) across orthogonal planes was calculated for each fetus, and the relationship between APFV and EGA was mathematically modeled. Coronal, transverse, and sagittal views were compared with correlations and Bland-Altman plots. Two additional observers repeated the measurements for a small subset of fetuses (n = 5). Paired t test analyses were also performed to determine significant differences between sagittal, transverse, and coronal measurements, as well as to determine preliminary intraobserver and interobserver variability of measurements in a subset of cases. RESULTS The relationship between APFV (in cubic centimeters) and EGA (in weeks) was well described by a single exponential function [APFV = 0.689 exp(EGA/9.10)]. APFV doubling time was 6.31 weeks. Root-mean-square variation of values around the model line was 1.63 cm(3). There was no statistically significant intra- or interobserver variation (P > .16 for all fetuses) at preliminary analysis. No correlation between APFV and FL could be found. CONCLUSION The normal fetal PFV growth curve generated in this study may have potential as a model for clinical application.
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Wilson RD, Pawel B, Bebbington M, Johnson MP, Lim FY, Stamilio D, Silber A, Zakii E, Flake AW. Congenital pulmonary lymphangiectasis sequence: a rare, heterogeneous, and lethal etiology for prenatal pleural effusion. Prenat Diagn 2006; 26:1058-61. [PMID: 16941717 DOI: 10.1002/pd.1555] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Case report and literature review for congenital pulmonary lymphangiectasis (CPL) CASE REPORT: Male fetus with bilateral pleural effusion, thoracoamniotic shunt, preterm delivery, and prolonged neonatal course with neonatal death at 3 months. Autopsy-identified CPL. DISCUSSION Review of pathology, clinical course, and genetics of CPL. CONCLUSION This postnatal diagnosis of CPL/Hennekam syndrome must be considered with prenatal counseling regarding a fetus with bilateral pleural effusions. This pathological entity is autosomal recessive and has a significant risk of lethality.
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Liechty KW, Hedrick HL, Hubbard AM, Johnson MP, Wilson RD, Ruchelli ED, Howell LJ, Crombleholme TM, Flake AW, Adzick NS. Severe pulmonary hypoplasia associated with giant cervical teratomas. J Pediatr Surg 2006; 41:230-3. [PMID: 16410139 DOI: 10.1016/j.jpedsurg.2005.10.081] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND The use of the ex utero intrapartum treatment (EXIT) procedure has salvaged many fetuses with giant neck masses. Despite an adequate airway, a subset of these patients die from an inability to achieve adequate gas exchange. METHODS We reviewed our experience with the EXIT procedure from 1996 to 2004. The EXIT was used to deliver 23 fetuses with giant neck masses. RESULTS Three fetuses with giant cervical teratomas died of severe pulmonary hypoplasia. On postmortem, these patients had severe airway distortion by the mass. The carina was retracted superiorly to the first or second rib resulting in compression of the lungs in the apices of the chest and pulmonary hypoplasia. Hypoplasia was reflected in the lung weights of 24 vs 38 g and 17 vs 34 g for age-matched normal lung. CONCLUSIONS Unsuspected obstructive fetal neck masses can be fatal because of an inability to secure an airway. Prenatal ultrasonography can identify fetuses at risk, allowing the fetus to be salvaged using the EXIT procedure. Despite obtaining airway control, a subset of these patients will die because of pulmonary hypoplasia. When counseling patients with large cervical masses it is important to discuss potential pulmonary hypoplasia in these patients.
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Ilagan (F) JG, Wilson RD, Johnson MP, Hedrick HL, Flake AW, Bebbington M, Adzick NS. Pregnancy outcomes following bipolar umbilical cord cauterization (UCC) for selective termination in complicated monochorionic (MC) multiple gestations. Am J Obstet Gynecol 2005. [DOI: 10.1016/j.ajog.2005.10.494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Biard JM, Johnson MP, Carr MC, Wilson RD, Hedrick HL, Pavlock C, Adzick NS. Long-term outcomes in children treated by prenatal vesicoamniotic shunting for lower urinary tract obstruction. Obstet Gynecol 2005; 106:503-8. [PMID: 16135579 DOI: 10.1097/01.aog.0000171117.38929.eb] [Citation(s) in RCA: 166] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Limited information is available about long-term outcomes in children treated prenatally for lower urinary tract obstruction. Our aim was to evaluate outcomes in children treated in utero with vesicoamniotic shunts. METHODS Clinical outcomes in 20 pregnancies with a singleton male fetus, oligo/anhydramnios, and lower urinary tract obstruction were studied using chart review and phone and written clinical questionnaire for parents, pediatricians, and urologists. RESULTS Overall 1-year survival was 91%. Two neonatal deaths occurred from pulmonary hypoplasia. Mean gestational age at delivery was 34.6 weeks, mean days from shunting to delivery were 84.4, and mean birth weight was 2,574 g. Prenatal urinary prognosis was good in 13, borderline in 2, and poor in 3 of the survivors. Mean age at follow-up was 5.83 years. Posterior urethral valves were confirmed in 7 males, urethral atresia in 4, and prune belly syndrome in 7. Eight children had acceptable renal function, 4 had mild insufficiency, and 6 required dialysis and eventual renal transplant. Eleven children had normal bladder function with spontaneous voiding, 6 required catheterization, and 1 child still had a vesicostomy. Height and weight were below the 25th percentile in 9 children. Persistent respiratory problems were present in 8, musculoskeletal problems in 9, and frequent urinary tract infections were reported in 9. Health-related quality of life results in our group with lower urinary tract obstruction were similar to those in a healthy child population. CONCLUSION Male children who underwent prenatal bladder shunting were neurodevelopmentally normal. Although one third of the surviving babies required dialysis and transplantation, the majority have acceptable renal and bladder function and report satisfactory quality of life. LEVEL OF EVIDENCE III.
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Zimmer WMX, Madsen PT, Teloni V, Johnson MP, Tyack PL. Off-axis effects on the multipulse structure of sperm whale usual clicks with implications for sound production. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2005; 118:3337-45. [PMID: 16334703 DOI: 10.1121/1.2082707] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Sperm whales (Physeter macrocephalus) produce multipulsed clicks with their hypertrophied nasal complex. The currently accepted view of the sound generation process is based on the click structure measured directly in front of, or behind, the whale where regular interpulse intervals (IPIs) are found between successive pulses in the click. Most sperm whales, however, are recorded with the whale in an unknown orientation with respect to the hydrophone where the multipulse structure and the IPI do not conform to a regular pulse pattern. By combining far-field recordings of usual clicks with acoustic and orientation information measured by a tag on the clicking whale, we analyzed clicks from known aspects to the whale. We show that a geometric model based on the bent horn theory for sound production can explain the varying off-axis multipulse structure. Some of the sound energy that is reflected off the frontal sac radiates directly into the water creating an intermediate pulse p1/2 seen in off-axis recordings. The powerful p1 sonar pulse exits the front of the junk as predicted by the bent-horn model, showing that the junk of the sperm whale nasal complex is both anatomically and functionally homologous to the melon of smaller toothed whales.
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Johnson MP, Lea RA, Colson NJ, Macmillan JC, Griffiths LR. A population genomics overview of the neuronal nitric oxide synthase (nNOS) gene and its relationship to migraine susceptibility. Cell Mol Biol (Noisy-le-grand) 2005; 51:285-92. [PMID: 16191396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2004] [Accepted: 12/21/2004] [Indexed: 05/04/2023]
Abstract
The ubiquitous chemical messenger molecule nitric oxide (NO) has been implicated in a diverse range of biological activities including neurotransmission, smooth muscle motility and mediation of nociception. Endogenous synthesis of NO by the neuronal isoform of the nitric oxide synthase gene family has an essential role within the central and peripheral nervous systems in addition to the autonomic innervation of cerebral blood vessels. To investigate the potential role of NO and more specifically the neuronal nitric oxide synthase (nNOS) gene in migraine susceptibility, we investigated two microsatellite repeat variants residing within the 5' and 3' regions of the nNOS gene. Population genomic evaluation of the two nNOS repeat variants indicated significant linkage disequilibrium between the two loci. Z-DNA conformational sequence structures within the 5' region of the nNOS gene have the potential to enhance or repress gene promoter activity. We suggest that genetic analysis of this 5' repeat variant is the more functional variant expressing gene wide information that could affect endogenous NO synthesis and potentially result in diseased states. However, no association with migraine (with or without aura) was seen in our extensive case-control cohort (n = 579 affected with matched controls), when both the 5' and 3' genetic variants were investigated.
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Keswani SG, Crombleholme TM, Rychik J, Tian Z, Mackenzie TC, Johnson MP, Wilson RD, Flake AW, Hedrick HL, Howell LJ, Adzick NS. Impact of Continuous Intraoperative Monitoring on Outcomes in Open Fetal Surgery. Fetal Diagn Ther 2005; 20:316-20. [PMID: 15980648 DOI: 10.1159/000085093] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2004] [Accepted: 01/07/2005] [Indexed: 11/19/2022]
Abstract
OBJECTIVES There are shifts in fetal hemodynamics during open fetal surgery that were not appreciated until the use of intraoperative fetal echocardiography. We have developed an intraoperative monitoring strategy to continuously assess fetal hemodynamics. We hypothesized that this approach would enhance intraoperative management and survival. METHODS Medical records of open fetal surgery patients were reviewed since the implementation of this approach. Intraoperative fetal monitoring was accomplished by continuous echocardiography, pulse oximetry, establishment of intravenous access, and arterial blood gas and hemoglobin measurement. Overall survival was compared to fetal surgeries performed prior implementation of this monitoring strategy. RESULTS Resections of a congenital cystic adenomatoid malformation or a sacrococcygeal teratoma in nine hydropic fetuses were performed while using this monitoring strategy. Intraoperative echocardiography resulted in a change of management in 7 of 9 fetuses. The main observations on fetal echocardiography resulting in intraoperative intervention were decreased ventricular filling, bradycardia, and decreased ventricular contractility. Therapy included administration of volume expanders and/or inotropic agents. Overall fetal survival was 78% compared to a survival of 42% prior to the implementation of this approach. CONCLUSION Continuous intraoperative fetal monitoring provides real time assessment of fetal hemodynamics which results in changes in intraoperative management. The overall outcomes in these critically ill fetuses have been improved.
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Hedrick HL, Flake AW, Crombleholme TM, Howell LJ, Johnson MP, Wilson RD, Adzick NS. The ex utero intrapartum therapy procedure for high-risk fetal lung lesions. J Pediatr Surg 2005; 40:1038-43; discussion 1044. [PMID: 15991193 DOI: 10.1016/j.jpedsurg.2005.03.024] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Indications for the ex utero intrapartum therapy (EXIT) procedure have expanded to include any fetal anomaly in which resuscitation of the neonate may be compromised. METHODS We reviewed the medical records of 9 patients after resection of lung lesions during the EXIT procedure. RESULTS The mean gestational age at EXIT procedure was 35.4 weeks. All lung masses maintained large sizes late into gestation with mean mass volume/head circumference ratio of 2.5 at presentation and 2.2 at EXIT. Seven of 9 fetuses demonstrated hydropic changes (n = 6) and/or polyhydramnios (n = 5), and underwent prenatal intervention including thoracentesis, thoracoamniotic shunt placement, amnioreduction, and/or betamethasone administration. Overall survival after EXIT for lung mass resection was 89%. The average time on placental bypass was 65 minutes. Postnatal complications included reoperation for air leak (n = 1), reoperation for bleeding (n = 1), and death from sepsis and prematurity (n = 1). Venoarterial extracorporeal membrane oxygenation was used in 4 neonates for persistent pulmonary hypertension. Maternal prenatal complications included polyhydramnios (n = 5), preterm labor (n = 4), and chorioamnionitis (n = 1). One mother required perioperative blood transfusion. CONCLUSION The EXIT procedure allows for controlled resection of large fetal lung lesions at delivery, avoiding acute respiratory decompensation related to mediastinal shift, air trapping, and compression of normal lung.
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Zimmer WMX, Johnson MP, Madsen PT, Tyack PL. Echolocation clicks of free-ranging Cuvier's beaked whales (Ziphius cavirostris). THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2005; 117:3919-27. [PMID: 16018493 DOI: 10.1121/1.1910225] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Strandings of beaked whales of the genera Ziphius and Mesoplodon have been reported to occur in conjunction with naval sonar use. Detection of the sounds from these elusive whales could reduce the risk of exposure, but descriptions of their vocalizations are at best incomplete. This paper reports quantitative characteristics of clicks from deep-diving Cuvier's beaked whales (Ziphius cavirostris) using a unique data set. Two whales in the Ligurian Sea were simultaneously tagged with sound and orientation recording tags, and the dive tracks were reconstructed allowing for derivation of the range and relative aspect between the clicking whales. At depth, the whales produced trains of regular echolocation clicks with mean interclick intervals of 0.43 s (+/- 0.09) and 0.40 s (+/- 0.07). The clicks are frequency modulated pulses with durations of approximately 200 micros and center frequencies around 42 kHz, -10 dB bandwidths of 22 kHz, and Q(3 dB) of 4. The sound beam is narrow with an estimated directionality index of more than 25 dB, source levels up to 214 dB(pp) re: 1 microPa at 1 m, and energy flux density of 164 dB re: 1 microPa2 s. As the spectral and temporal properties are different from those of nonziphiid odontocetes the potential for passive detection is enhanced.
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Zimmer WMX, Tyack PL, Johnson MP, Madsen PT. Three-dimensional beam pattern of regular sperm whale clicks confirms bent-horn hypothesis. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2005; 117:1473-1485. [PMID: 15807035 DOI: 10.1121/1.1828501] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The three-dimensional beam pattern of a sperm whale (Physeter macrocephalus) tagged in the Ligurian Sea was derived using data on regular clicks from the tag and from hydrophones towed behind a ship circling the tagged whale. The tag defined the orientation of the whale, while sightings and beamformer data were used to locate the whale with respect to the ship. The existence of a narrow, forward-directed P1 beam with source levels exceeding 210 dBpeak re: 1 microPa at 1 m is confirmed. A modeled forward-beam pattern, that matches clicks >20 degrees off-axis, predicts a directivity index of 26.7 dB and source levels of up to 229 dBpeak re: 1 microPa at 1 m. A broader backward-directed beam is produced by the P0 pulse with source levels near 200 dBpeak re: 1 microPa at 1 m and a directivity index of 7.4 dB. A low-frequency component with source levels near 190 dBpeak re: 1 microPa at 1 m is generated at the onset of the P0 pulse by air resonance. The results support the bent-horn model of sound production in sperm whales. While the sperm whale nose appears primarily adapted to produce an intense forward-directed sonar signal, less-directional click components convey information to conspecifics, and give rise to echoes from the seafloor and the surface, which may be useful for orientation during dives.
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Hooker SK, Miller PJO, Johnson MP, Cox OP, Boyd IL. Ascent exhalations of Antarctic fur seals: a behavioural adaptation for breath-hold diving? Proc Biol Sci 2005; 272:355-63. [PMID: 15734689 PMCID: PMC1634983 DOI: 10.1098/rspb.2004.2964] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2004] [Accepted: 09/28/2004] [Indexed: 11/12/2022] Open
Abstract
Novel observations collected from video, acoustic and conductivity sensors showed that Antarctic fur seals consistently exhale during the last 50-85% of ascent from all dives (10-160 m, n > 8000 dives from 50 seals). The depth of initial bubble emission was best predicted by maximum dive depth, suggesting an underlying physical mechanism. Bubble sound intensity recorded from one seal followed predictions of a simple model based on venting expanding lung air with decreasing pressure. Comparison of air release between dives, together with lack of variation in intensity of thrusting movement during initial descent regardless of ultimate dive depth, suggested that inhaled diving lung volume was constant for all dives. The thrusting intensity in the final phase of ascent was greater for dives in which ascent exhalation began at a greater depth, suggesting an energetic cost to this behaviour, probably as a result of loss of buoyancy from reduced lung volume. These results suggest that fur seals descend with full lung air stores, and thus face the physiological consequences of pressure at depth. We suggest that these regular and predictable ascent exhalations could function to reduce the potential for a precipitous drop in blood oxygen that would result in shallow-water blackout.
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Miller PJO, Johnson MP, Tyack PL. Sperm whale behaviour indicates the use of echolocation click buzzes "creaks" in prey capture. Proc Biol Sci 2005; 271:2239-47. [PMID: 15539349 PMCID: PMC1691849 DOI: 10.1098/rspb.2004.2863] [Citation(s) in RCA: 198] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
During foraging dives, sperm whales (Physeter macrocephalus) produce long series of regular clicks at 0.5-2 s intervals interspersed with rapid-click buzzes called "creaks". Sound, depth and orientation recording Dtags were attached to 23 whales in the Ligurian Sea and Gulf of Mexico to test whether the behaviour of diving sperm whales supports the hypothesis that creaks are produced during prey capture. Sperm whales spent most of their bottom time within one or two depth bands, apparently feeding in vertically stratified prey layers. Creak rates were highest during the bottom phase: 99.8% of creaks were produced in the deepest 50% of dives, 57% in the deepest 15% of dives. Whales swam actively during the bottom phase, producing a mean of 12.5 depth inflections per dive. A mean of 32% of creaks produced during the bottom phase occurred within 10 s of an inflection (13x more than chance). Sperm whales actively altered their body orientation throughout the bottom phase with significantly increased rates of change during creaks, reflecting increased manoeuvring. Sperm whales increased their bottom foraging time when creak rates were higher. These results all strongly support the hypothesis that creaks are an echolocation signal adapted for foraging, analogous to terminal buzzes in taxonomically diverse echolocating species.
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Merchant AM, Hedrick HL, Johnson MP, Wilson RD, Crombleholme TM, Howell LJ, Adzick NS, Flake AW. Management of fetal mediastinal teratoma. J Pediatr Surg 2005; 40:228-31. [PMID: 15868589 DOI: 10.1016/j.jpedsurg.2004.09.023] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND/PURPOSE Mediastinal teratomas are rare congenital germ cell tumors that prenatally can compress mediastinal structures and cause hydrops. Two possible presentations of massive fetal mediastinal teratoma include hydrops leading to fetal demise, or fetal esophageal and airway compression causing late-gestation polyhydramnios and preterm labor. The authors present 2 cases of fetal mediastinal teratoma that illustrate successful strategies for either of these presentations. METHODS A 37-year-old woman carrying a fetus with a mediastinal mass and secondary hydrops at 23 weeks of gestation underwent in utero resection of the mass. Delivery was by cesarean delivery at 25 weeks because of preterm labor. A 24-year-old mother carrying a fetus with a mediastinal mass and severe polyhydramnios at 36 weeks of gestation underwent an ex utero intrapartum therapy procedure for establishment of an airway and tumor resection on uteroplacental support. RESULTS These strategies resulted in physiologic improvement in the first case and controlled resection and resuscitation in the second. The first patient had significant sequelae of prematurity including bronchopulmonary dysplasia but is currently well at 9 months of age. The second patient is well at 1 year of age. CONCLUSIONS Massive fetal mediastinal teratoma can result in fetal or neonatal mortality by a variety of mechanisms. Optimal prenatal and perinatal management is required to salvage fetuses compromised by this lesion.
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Keswani SG, Crombleholme TM, Pawel BR, Johnson MP, Flake AW, Hedrick HL, Howell LJ, Wilson RD, Davis GH, Adzick NS. Prenatal Diagnosis and Management of Mainstem Bronchial Atresia. Fetal Diagn Ther 2004; 20:74-8. [PMID: 15608465 DOI: 10.1159/000081374] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2003] [Accepted: 03/19/2004] [Indexed: 11/19/2022]
Abstract
The prenatal diagnosis, natural history and management of mainstem bronchial atresia have not been described previously. We report two cases of prenatally diagnosed proximal bronchial atresia. The first patient presented at 18 weeks with sonographic and MRI findings consistent with bronchial atresia with fetal hydrops. The mother developed the mirror syndrome and labor was induced. A non-viable fetus was delivered at 25 weeks. The second patient presented at 16 weeks gestation with evidence of an intrathoracic mass that was subsequently prenatally diagnosed as a right mainstem bronchial atresia. The right lung increased rapidly in size and was associated with the onset of fetal hydrops. At 24 weeks, fetal pneumonectomy was performed but the fetus expired intraoperatively due to cardiovascular collapse. Post-mortem findings in both cases confirmed the presence of an atretic mainstem bronchus with massive enlargement of the lung. Bronchial atresia involving the mainstem bronchus is associated with a poor prognosis.
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Danzer E, Johnson MP, Bebbington M, Wilson RD, Bilaniuk L, Simon E, Flake A, Sutton L, Adzick NS. Correction of cerebrospinal fluid levels and brain growth demonstrated by serial fetal magnetic resonance imaging following. Am J Obstet Gynecol 2004. [DOI: 10.1016/j.ajog.2004.10.508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Danzer E, Johnson MP, Wilson RD, Flake AW, Hedrick HL, Sutton LN, Adzick NS. Fetal head biometry following in-utero repair of myelomeningocele. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2004; 24:606-611. [PMID: 15517548 DOI: 10.1002/uog.1780] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
OBJECTIVE To evaluate the impact of prenatal myelomeningocele repair on fetal head biometry. METHODS Fifty fetuses underwent open fetal myelomeningocele repair at our institution between January 1998 and July 2002. All had serial head circumference (HC) and lateral ventricular diameter (VD) measurements taken preoperatively and weekly for 8 weeks after repair. Cortical index (CI) was defined as HC/VD. Measurements were compared with gestational age-matched values from nomograms. One-sample t-test, ANOVA and repeated measures analysis were used to assess HC, VD and CI after fetal repair. RESULTS Preoperatively, the HC in fetuses with myelomeningocele was smaller than control values (186.4 vs. 198.8 mm, P = 0.0004). Eight weeks' postoperatively this difference had resolved (293 vs. 301.6 mm, P = 0.76). The mean increase in CI after repair was 20% (P = 0.02) compared with the predicted 51% in normal cases. The average increase in VD was 3.9 mm (38.8%, P < 0.001). CONCLUSIONS Mid-gestational repair of myelomeningocele alters fetal head growth. Increased CI suggests HC changes are not due to ventriculomegaly alone.
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Johnson MP, Nisenbaum ES, Large TH, Emkey R, Baez M, Kingston AE. Allosteric modulators of metabotropic glutamate receptors: lessons learnt from mGlu1, mGlu2 and mGlu5 potentiators and antagonists. Biochem Soc Trans 2004; 32:881-7. [PMID: 15494040 DOI: 10.1042/bst0320881] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Although relatively few G-protein-coupled receptors are Class C, in recent years, this small family of receptors has become a focal point for the discovery of new and exciting allosteric modulators. The mGlu (metabotropic glutamate) receptors are illustrative in the discovery of both positive and/or negative allosteric modulators with unique pharmacological properties. For instance, allosteric modulators of the mGlu2 receptor act as potentiators of glutamate responses in clonal expression systems and in native tissue assays. These potentiators act to increase the affinity of orthosteric agonists for the mGlu2 receptor and shift potency curves for the agonist to the left. In electrophysiological experiments, the potentiators show a unique activation-state-dependent presynaptic inhibition of glutamate release and significantly enhance the receptor-mediated increase in G-protein binding, as seen with autoradiography. Similarly, potentiators of mGlu5 have been described, as well as allosteric antagonists or inverse agonists of mGlu1 and mGlu5. Binding and activity of the modulators have recently indicated that positive and negative allosteric sites can be, but are not necessarily, overlapping. Compared with orthosteric ligands, these modulators display a unique degree of subtype selectivity within the highly conserved mGlu family of receptors and can have very distinct pharmacological properties, such as neuronal frequency-dependent activity. This short review describes some of the unique features of these mGlu1, mGlu2 and mGlu5 allosteric modulators.
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Biard JM, Wilson RD, Johnson MP, Hedrick HL, Schwarz U, Flake AW, Crombleholme TM, Adzick NS. Prenatally diagnosed giant omphaloceles: short- and long-term outcomes. Prenat Diagn 2004; 24:434-9. [PMID: 15229842 DOI: 10.1002/pd.894] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVES To review prenatal findings, short- and long-term outcomes of giant omphaloceles (GO) managed at a single institution (1996-2001). METHODS Prenatal findings and early postnatal outcomes were retrospectively reviewed. Clinical short- and long-term outcomes were analyzed in eight and five children respectively. Parents and physicians of the children were surveyed by written questionnaires about the children's subsequent health issues. (IRB 2002-2-2683). RESULTS Seventeen pregnancies with GO were identified: Eight fetuses were live born, four ended in (terminations), two died in utero and three were lost to follow-up. Live-born fetuses had prenatal ascites, extreme levocardia and were delivered by cesarean section at a mean of 37 weeks' gestation with a mean birth weight of 2903 g. All neonates required intubation. Two infants (2/8) died within one year. Four of the six survivors had respiratory insufficiency with a mean ventilation time of 76 days. Respiratory and feeding problems complicated the early neonatal course. Long-term follow-up was available for five patients (mean age of 33.2 months). Asthma, recurrent pulmonary infections, feeding problems, gastroesophageal reflux and failure to thrive were the major problems. CONCLUSIONS Respiratory and feeding problems were the most common neonatal and long-term medical management issues. Parents need to be counseled prenatally about the probability of multiple surgeries and long hospitalization following birth.
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Wilson RD, Johnson MP, Flake AW, Crombleholme TM, Hedrick HL, Wilson J, Adzick NS. Reproductive outcomes after pregnancy complicated by maternal-fetal surgery. Am J Obstet Gynecol 2004; 191:1430-6. [PMID: 15507978 DOI: 10.1016/j.ajog.2004.05.054] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE The reproductive outcomes for women after the pregnancy complicated by maternal-fetal surgery were evaluated to obtain evidence-based information for prenatal risk counseling. STUDY DESIGN The retrospective review identified 83 women with maternal-fetal surgery from a single institution (1996-2002). These women were sent a consent form and a questionnaire to document postoperative problems, fertility, obstetric outcomes, and psychosocial concerns in pregnancy after the index fetal therapy. Institutional Review Board approval was obtained from Committee for Protection of Human Subjects. RESULTS The total return rate was 55 (66%). The pregnancy rate was 62% (18% spontaneous abortion, 24% preterm delivery, and 58% term delivery). Complications were reported in 12 of 34 pregnancies (35%), including uterine dehiscence/rupture (12%/6%), cesarean hysterectomy (3%), and antepartum hemorrhage requiring transfusion (9%). CONCLUSION The reproductive outcome of uterine dehiscence, rupture, and hysterectomy was 12%, 6%, and 3%, respectively, after a pregnancy complicated by maternal-fetal surgery. The uterine rupture rate is similar to the rupture rate after "classical" cesarean section (4%-9%).
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Rychik J, Tian Z, Cohen MS, Ewing SG, Cohen D, Howell LJ, Wilson RD, Johnson MP, Hedrick HL, Flake AW, Crombleholme TM, Adzick NS. Acute Cardiovascular Effects of Fetal Surgery in the Human. Circulation 2004; 110:1549-56. [PMID: 15353490 DOI: 10.1161/01.cir.0000142294.95388.c4] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Prenatal surgery for congenital anomalies can prevent fetal demise or alter the course of organ development, resulting in a more favorable condition at birth. The indications for fetal surgery continue to expand, yet little is known about the acute sequelae of fetal surgery on the human cardiovascular system.
Methods and Results—
Echocardiography was used to evaluate the heart before, during, and early after fetal surgery for congenital anomalies, including repair of myelomeningocele (MMC, n=51), resection of intrathoracic masses (ITM, n=15), tracheal occlusion for congenital diaphragmatic hernia (CDH, n=13), and resection of sacrococcygeal teratoma (SCT, n=4). Fetuses with MMC all had normal cardiovascular systems entering into fetal surgery, whereas those with ITM, CDH, and SCT all exhibited secondary cardiovascular sequelae of the anomaly present. At fetal surgery, heart rate increased acutely, and combined cardiac output diminished at the time of fetal incision for all groups including those with MMC, which suggests diminished stroke volume. Ventricular dysfunction and valvular dysfunction were identified in all groups, as was acute constriction of the ductus arteriosus. Fetuses with ITM and SCT had the most significant changes at surgery.
Conclusions—
Acute cardiovascular changes take place during fetal surgery that are likely a consequence of the physiology of the anomaly and the general effects of surgical stress, tocolytic agents, and anesthesia. Echocardiographic monitoring during fetal surgery is an important adjunct in the management of these patients.
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Wilson RD, Johnson MP. Congenital Abdominal Wall Defects: An Update. Fetal Diagn Ther 2004; 19:385-98. [PMID: 15305094 DOI: 10.1159/000078990] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2003] [Accepted: 03/12/2004] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To review published peer-reviewed literature regarding abdominal wall defects including gastroschisis and omphalocele. METHODS Review of published peer-reviewed literature using Med Line 1985-2003 and textbooks. RESULTS Gastroschisis and omphalocele literature is reviewed using pathology, incidence and epidemiology, prenatal evaluation, pregnancy and delivery management, postnatal outcome and fetal therapy. CONCLUSION Gastroschisis and omphalocele are common abdominal wall defects and have significant morbidity and mortality.
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Wilson RD, Baxter JK, Johnson MP, King M, Kasperski S, Crombleholme TM, Flake AW, Hedrick HL, Howell LJ, Adzick NS. Thoracoamniotic Shunts: Fetal Treatment of Pleural Effusions and Congenital Cystic Adenomatoid Malformations. Fetal Diagn Ther 2004; 19:413-20. [PMID: 15305098 DOI: 10.1159/000078994] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2003] [Accepted: 08/26/2003] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To determine whether fetuses that underwent thoracoamniotic shunt placement for treatment of pleural effusion (PE) or macrocystic congenital cystic adenomatoid malformation (CCAM) have an improved outcome as compared with an untreated population. METHODS A retrospective review from a single tertiary center was performed using thoracoamniotic shunt placement to treat PE or macrocystic CCAM between 1998 and 2001. Thoracoamniotic shunts were used on 26 occasions in 19 pregnancies. RESULTS The average gestational age at the diagnosis of PE and CCAM was 22 + 4 and 20 + 0 weeks, respectively. Shunts were offered in pregnancies complicated by hydrops or at significant risk for pulmonary hypoplasia. Shunts were placed at 26 + 2 weeks (average) and 23 + 1 weeks (average) in the PE and CCAM groups, respectively. In CCAM patients, the mean pre- and postshunting mass volumes were 50.5 and 25.7 cm(3), representing a 51% reduction in mass volume following shunt placement. In the PE group, the average delivery age was 33 + 5 weeks, with an average shunt placement to delivery time of 7 + 3 weeks. In the CCAM group, the average delivery was 33 + 3 weeks, with an average shunt placement to delivery time of 10 + 2 weeks. The postnatal survival rates were 67% (6/9) and 70% (7/10) in the PE and CCAM groups, respectively. CONCLUSIONS (1) Thoracoamniotic shunts should be considered as a treatment option for selected PE or macrocystic CCAM fetuses with hydrops or a significant risk for pulmonary hypoplasia; (2) the neonatal survival with shunting was similar for PE and CCAM groups and was improved as compared with literature reports, and (3) fetuses with CCAM presented earlier with hydrops than those with PE. Successful shunting resulted in a prolongation of pregnancy into the 3rd trimester in both groups.
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Miller PJO, Johnson MP, Tyack PL, Terray EA. Swimming gaits, passive drag and buoyancy of diving sperm whales Physeter macrocephalus. ACTA ACUST UNITED AC 2004; 207:1953-67. [PMID: 15107448 DOI: 10.1242/jeb.00993] [Citation(s) in RCA: 181] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Drag and buoyancy are two primary external forces acting on diving marine mammals. The strength of these forces modulates the energetic cost of movement and may influence swimming style (gait). Here we use a high-resolution digital tag to record depth, 3-D orientation, and sounds heard and produced by 23 deep-diving sperm whales in the Ligurian Sea and Gulf of Mexico. Periods of active thrusting versus gliding were identified through analysis of oscillations measured by a 3-axis accelerometer. Accelerations during 382 ascent glides of five whales (which made two or more steep ascents and for which we obtained a measurement of length) were strongly affected by depth and speed at Reynold's numbers of 1.4-2.8x10(7). The accelerations fit a model of drag, air buoyancy and tissue buoyancy forces with an r(2) of 99.1-99.8% for each whale. The model provided estimates (mean +/- S.D.) of the drag coefficient (0.00306+/-0.00015), air carried from the surface (26.4+/-3.9 l kg(-3) mass), and tissue density (1030+/-0.8 kg m(-3)) of these five animals. The model predicts strong positive buoyancy forces in the top 100 m of the water column, decreasing to near neutral buoyancy at 250-850 m. Mean descent speeds (1.45+/-0.19 m s(-1)) were slower than ascent speeds (1.63+/-0.22 m s(-1)), even though sperm whales stroked steadily (glides 5.3+/-6.3%) throughout descents and employed predominantly stroke-and-glide swimming (glides 37.7+/-16.4%) during ascents. Whales glided more during portions of dives when buoyancy aided their movement, and whales that glided more during ascent glided less during descent (and vice versa), supporting the hypothesis that buoyancy influences behavioural swimming decisions. One whale rested at approximately 10 m depth for more than 10 min without fluking, regulating its buoyancy by releasing air bubbles.
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Nowacek DP, Johnson MP, Tyack PL. North Atlantic right whales (Eubalaena glacialis) ignore ships but respond to alerting stimuli. Proc Biol Sci 2004; 271:227-31. [PMID: 15058431 PMCID: PMC1691586 DOI: 10.1098/rspb.2003.2570] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
North Atlantic right whales were extensively hunted during the whaling era and have not recovered. One of the primary factors inhibiting their recovery is anthropogenic mortality caused by ship strikes. To assess risk factors involved in ship strikes, we used a multi-sensor acoustic recording tag to measure the responses of whales to passing ships and experimentally tested their responses to controlled sound exposures, which included recordings of ship noise, the social sounds of conspecifics and a signal designed to alert the whales. The whales reacted strongly to the alert signal, they reacted mildly to the social sounds of conspecifics, but they showed no such responses to the sounds of approaching vessels as well as actual vessels. Whales responded to the alert by swimming strongly to the surface, a response likely to increase rather than decrease the risk of collision.
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Hedrick HL, Crombleholme TM, Flake AW, Nance ML, von Allmen D, Howell LJ, Johnson MP, Wilson RD, Adzick NS. Right congenital diaphragmatic hernia: Prenatal assessment and outcome. J Pediatr Surg 2004; 39:319-23; discussion 319-23. [PMID: 15017545 DOI: 10.1016/j.jpedsurg.2003.11.006] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE To understand the natural history of right congenital diaphragmatic hernia (CDH), the authors retrospectively reviewed 27 cases of right CDH that presented for prenatal evaluation or postnatal treatment. METHODS Between 1995 and September 2002, a total of 194 cases of fetal CDH were evaluated and included 22 right-sided defects. The authors reviewed prenatal diagnostic studies (ultrasound scan, magnetic resonance imaging [MRI] echocardiography) and pre- and postnatal outcomes in these 22 cases of right CDH. Five additional cases of right CDH without a prenatal diagnosis were reviewed. RESULTS The mean gestational age at evaluation was 26.1 weeks. The lung area to head circumference ratio (LHR) ranged from 0.32 to 2.5. In all cases, the fetal liver was herniated into the right chest. Associated anomalies were common. There were no karyotype abnormalities (17 of 22 tested). There were 4 terminations. Nine of the 18 (50%) continuing pregnancies had polyhydramnios, premature rupture of membranes, or preterm labor. The mean gestational age at birth was 36.8 weeks. One patient underwent tracheal occlusion at 27 weeks, and 2 patients died before postnatal repair. Overall survival rate (22 prenatal plus 5 postnatal diagnoses) was 19 of 27 (70%). Postnatal survival rate was 19 of 23 (83%). A Gore-tex (W. L. Gore and Associates, Flagstaff, AZ) patch was utilized in 14 of 21 neonates undergoing surgery. Twelve of 23 (52%) required extracorporeal membrane oxygenation (ECMO) with a 75% survival rate. Significant morbidity occurred in 10 of 19 survivors and included neurologic sequelae in 6 of 19 (32%). CONCLUSIONS MRI was helpful in the determination of liver position and confirmation of diagnosis. The high incidence of preterm complications, frequent need for ECMO, and high prevalence of comorbidities are indicative of the severity of this CDH population and warrant close prenatal surveillance and delivery at a tertiary care center with ECMO capability.
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Hedrick HL, Flake AW, Crombleholme TM, Howell LJ, Johnson MP, Wilson RD, Adzick NS. Sacrococcygeal teratoma: prenatal assessment, fetal intervention, and outcome. J Pediatr Surg 2004; 39:430-8; discussion 430-8. [PMID: 15017565 DOI: 10.1016/j.jpedsurg.2003.11.005] [Citation(s) in RCA: 203] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
PURPOSE To understand the natural history and define indications for fetal intervention in sacrococcygeal teratoma (SCT), the authors reviewed all cases of fetal SCT presenting for evaluation. METHODS Prenatal diagnostic studies including ultrasound scan, magnetic resonance imaging (MRI), echocardiography and pre- and postnatal outcomes were reviewed in 30 cases of SCT that presented between September 1995 and January 2003. RESULTS The mean gestational age (GA) at presentation was 23.9 weeks (range, 19 to 38.5) with 3 sets of twins (10%). Overall outcomes included 4 terminations, 5 fetal demises, 7 neonatal deaths, and 14 survivors. Significant obstetric complications occurred in 81% of the 26 continuing pregnancies: polyhydramnios (n = 7), oligohydramnios (n = 4), preterm labor (n = 13), preeclampsia (n = 4), gestational diabetes (n = 1), HELLP syndrome (n = 1), and hyperemesis (n = 1). Fetal intervention included cyst aspiration (n = 6), amnioreduction (n = 3), amnioinfusion (n = 1), and open fetal surgical resection (n = 4). Indications for cyst aspiration and amnioreduction were maternal discomfort, preterm labor, and prevention of tumor rupture at delivery. Although 15 SCTs were solid causing risk for cardiac failure, only 4 fetuses met criteria for fetal debulking based on ultrasonographic and echocardiographic evidence of impending high output failure and favorable anatomy at 21, 23.6, 25, and 26 weeks' gestation. Intraoperative events included maternal blood transfusion (n = 1), fetal blood transfusion (n = 2), chorioamniotic membrane separation (n = 2), and fetal arrest requiring successful cardiopulmonary resuscitation (CPR) (n = 1). In the fetal resection group, 3 of 4 survived with mean GA at delivery of 29 weeks (range, 27.6 to 31.7 weeks), mean birth weight of 1.3 kg, hospital stay ranging from 16 to 34 weeks, and follow-up ranging from 20 months to 6 years. Postnatal complications in the fetal surgery group included neonatal death (n = 1, secondary to premature closure of ductus arteriosus with cardiac failure), embolic event (n = 1, resulting in unilateral renal agenesis, jejunal atresia), chronic lung disease (n = 1), and tumor recurrence (n = 1). CONCLUSIONS For fetal SCT, the rapidity at which cardiac compromise can develop and the high incidence of obstetric complications warrant close prenatal surveillance. Amnioreduction, cyst aspiration, and surgical debulking are potentially life-saving interventions.
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Olutoye OO, Johnson MP, Coleman BG, Crombleholme TM, Adzick NS, Flake AW. Abnormal Umbilical Cord Doppler Sonograms May Predict Impending Demise in Fetuses with Sacrococcygeal Teratoma. Fetal Diagn Ther 2003; 19:35-9. [PMID: 14646415 DOI: 10.1159/000074257] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2001] [Accepted: 11/26/2002] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To identify factors predictive of fetal demise in fetuses with sacrococcygeal teratoma (SCT). METHOD The recent management of monochorionic twins discordant for a large SCT and a singleton with a large SCT was reviewed. RESULTS Serial fetal echocardiography and ultrasonography with Doppler flow measurements documented rapid growth of the SCT in both cases with a relatively modest increase in combined cardiac output. No placentomegaly or hydrops was observed at any time. In both fetuses with SCT, evolution of abnormal umbilical artery waveforms was observed with the ultimate development of reversed end-diastolic umbilical arterial flow that was followed by sudden fetal demise. CONCLUSION Death in these 2 fetuses with large SCTs in the absence of placentomegaly/hydrops or hemodynamic changes suggestive of evolving high-output failure suggests a previously unrecognized mechanism of death in fetuses with large rapidly growing SCTs. In these cases, fetal demise may only be heralded by abnormal umbilical artery waveforms that progress to the premorbid observation of reversed diastolic umbilical artery blood flow. Umbilical artery waveform analysis should be closely monitored with other hemodynamic parameters in fetuses with large SCTs. In such fetuses, depending on the gestational age, abnormalities in umbilical artery waveform should be considered indications for early delivery or in utero intervention to prevent fetal demise.
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Danzer E, Johnson MP, Wilson R, Hedrick H, Crombleholme T, Flake A, Schwarz U, Shabbout M, Sutton L, Adzick N. Fetal brain growth and head biometry following in utero repair of myelomeningocele (MMC). Am J Obstet Gynecol 2003. [DOI: 10.1016/j.ajog.2003.10.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Johnson MP, Sutton LN, Rintoul N, Crombleholme TM, Flake AW, Howell LJ, Hedrick HL, Wilson RD, Adzick NS. Fetal myelomeningocele repair: short-term clinical outcomes. Am J Obstet Gynecol 2003; 189:482-7. [PMID: 14520222 DOI: 10.1067/s0002-9378(03)00295-3] [Citation(s) in RCA: 175] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE The study was undertaken to evaluate short-term clinical outcomes with antenatal myelomeningocele (MMC) repair. STUDY DESIGN Retrospective review of 50 fetuses that underwent open fetal MMC closure was performed. Inclusion criteria included less than 26 weeks' gestation, thoracic to S1 level defect, absent clubfoot deformity, Arnold-Chiari malformation, ventriculomegaly less than 17 mm, normal karyotype, and no other anomalies. RESULTS Perinatal survival was 94% (47/50 fetuses). Mean age at delivery was 34 weeks 3 days. All fetuses demonstrated reversal of hindbrain herniation. Forty-three percent of the 50 fetuses have required ventriculoperitoneal shunting compared with 100% thoracic, 88% lumbar, and 68% sacral (85% overall) in 297 historic controls. Better-than-predicted leg function was seen in 57% of thoracic and lumbar level lesion patients. CONCLUSION Early experience with fetal MMC repair suggests a decreased need for ventriculoperitoneal shunting, arrest or slowing of progressive ventriculomegaly, and consistent resolution of hindbrain herniation. However, further long-term follow-up is needed to evaluate neurodevelopment and bladder and bowel function.
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Olutoye OO, Johnson MP, Coleman BG, Crombleholme TM, Adzick NS, Flake AW. Abnormal Umbilical Cord Dopplers May Predict Impending Demise in Fetuses with Sacrococcygeal Teratoma. Fetal Diagn Ther 2003; 18:428-31. [PMID: 14564114 DOI: 10.1159/000073137] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2002] [Accepted: 11/26/2002] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To identify factors predictive of fetal demise in fetuses with sacrococcygeal teratoma (SCT). METHOD The recent management of monochorionic twins discordant for a large SCT and a singleton with a large SCT were reviewed. RESULTS Serial fetal echocardiography and ultrasonography with Doppler flow measurements documented rapid growth of the SCT in both cases with a relatively modest increase in combined cardiac output. No placentomegaly or hydrops was observed at any time. In both fetuses with SCT, evolution of abnormal umbilical artery waveforms was observed with the ultimate development of reversed end-diastolic umbilical arterial flow that was followed by sudden fetal demise. CONCLUSION Death in these 2 fetuses with large SCTs in the absence of placentomegaly/hydrops or hemodynamic changes suggestive of evolving high-output failure suggests a previously unrecognized mechanism of death in fetuses with large rapidly growing SCTs. In these cases, fetal demise may only be heralded by abnormal umbilical artery waveforms that progress to the premorbid observation of reversed diastolic umbilical artery blood flow. Umbilical artery waveform analysis should be closely monitored with other hemodynamic parameters in fetuses with large SCTs. In such fetuses, depending on the gestational age, abnormalities in umbilical artery waveform should be considered indications for early delivery or in utero intervention to prevent fetal demise.
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Wilson RD, Johnson MP, Crombleholme TM, Flake AW, Hedrick HL, King M, Howell LJ, Adzick NS. Chorioamniotic membrane separation following open fetal surgery: pregnancy outcome. Fetal Diagn Ther 2003; 18:314-20. [PMID: 12913340 DOI: 10.1159/000071972] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To review the incidence of posthysterotomy chorioamniotic membrane separation and delivery outcome following open fetal surgery [myelomeningocele (MMC); cystic adenomatoid malformation (CCAM); congenital diaphragmatic hernia (CDH); sacrococcygeal teratoma (SCT)]. STUDY DESIGN Retrospective review of a maternal population undergoing open fetal surgery at a single tertiary level program (1998-2001) following the initiation of close postoperative ultrasound follow-up for membrane separation. Onset of membrane separation was coded as not present (NP), immediate (<2 weeks) or delayed (>2 weeks) from day of surgery. RESULTS Fifty-three charts were reviewed: MMC 43, CCAM 7, CDH 1, and SCT 2. In the MMC group there were 26 NP, 8 immediate, and 9 delayed. Preterm labor occurred in 4 patients with only 2 having had membrane separation. Risk of membrane separation is increased for surgery done at less than 23 weeks gestation (p < 0.005). Delay from MMC surgery to delivery was 11.0, 9.8, 12.0 weeks for NP, immediate, and delay, respectively. In the MMC group, there were 3 neonatal deaths (NND) at 9, 9, and 21 days post surgery (PROM/PTL; chorioamnionitis, PROM/PTL, respectively). No membrane separation was present in the CCAM, CDH, and SCT cases. CONCLUSIONS (1) Membrane separation was significantly more likely to occur if surgery was performed prior to 23 weeks. (2) Membrane separation post hysterotomy (17/50 = 34%) may be associated with an increased risk of PROM but not delivery before 30 weeks gestation. (3) Delivery prior to 33 weeks gestation for MMC groups was 12/43 (28%) with 3 NND (7%). (4) Elective delivery at 36-37 weeks gestation was possible for 43% of the fetal surgery population.
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Wilson RD, Johnson MP. Prenatal ultrasound guided percutaneous shunts for obstructive uropathy and thoracic disease. Semin Pediatr Surg 2003; 12:182-9. [PMID: 12961112 DOI: 10.1016/s1055-8586(03)00027-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The authors reviewed the status of closed ultrasound-guided fetal therapy using a pigtail shunt to create vesicoamniotic or thoracoamniotic decompression of the fluid-filled space. This review includes published and textbook reports of in utero therapy for bladder obstruction, pleural effusion, and macrocystic adenomatoid malformation from 1985 through 2002. For fetuses affected by lower urinary tract obstruction, the key component is identifying those fetuses that have retained renal function and are most likely to benefit from in utero shunting. This good prognosis group has been shown to have improved survival rate and a lower incidence of renal failure. Complications of fetal loss are estimated at 5% owing to the shunt procedure, and the risk of shunt displacement varies from 30% to 50%. Hydrops secondary to primary PE has been shown to be associated with low fetal and neonatal survival at 21% to 23%. Treatment by thoracoamniotic shunting increases survival rate to 75%. The fetus with a macrocystic CCAM and secondary hydrops should be considered a candidate for thoracoamniotic shunt to decrease CCAM volume, reverse hydrops, and improve survival rate. Thoracoamniotic shunt and thoracocentesis pregnancy loss risks for pleural effusion (PE) and macrocystic adenomatoid malformation of the lung (CCAM) are 5% and 0.5% to 1.0%, respectively.
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Abstract
INTRODUCTION Although in utero treatment of myelomeningocele shows promise in decreasing the morbidity of this disease, the risks to the fetus are significant, and the benefits are unproven. TRIAL The upcoming trial represents one of the few times that the pediatric neurosurgical community has come together to test a new procedure.
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Lim FY, Crombleholme TM, Hedrick HL, Flake AW, Johnson MP, Howell LJ, Adzick NS. Congenital high airway obstruction syndrome: natural history and management. J Pediatr Surg 2003; 38:940-5. [PMID: 12778398 DOI: 10.1016/s0022-3468(03)00128-3] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Congenital high airway obstruction syndrome (CHAOS) is a life-threatening condition with a poorly understood natural history. METHODS A retrospective review of five patients with CHAOS between 1997 and 2002 was performed. RESULTS All fetuses had large echogenic lungs, dilated airways, inverted diaphragms, and massive ascites. One fetus with a laryngeal cyst was terminated at 22 weeks. A twin fetus with findings suggestive of a tracheal web had progressive hydrops, which led to fetal demise. The remaining 3 patients delivered via the ex utero intrapartum treatment (EXIT) procedure survived. The first patient tolerated progressive hydrops for 12 weeks in utero. He had tracheal atresia but underwent laryngotracheoplasty successfully. He is the first long-term CHAOS survivor and is speaking at 5 years of age. The 2 patients with relatively stable lung volumes prenatally have laryngeal atresia with a pinpoint posterior laryngeal fistula. Their postnatal clinical courses were much more benign than the first survivor. CONCLUSIONS The prenatal natural history and postnatal course of CHAOS depends on whether the airway obstruction is complete. The EXIT procedure offers the potential for salvage of this otherwise lethal condition. Hydrops may be well tolerated prenatally for weeks with potential resolution if airway fistulization is present.
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Keswani SG, Johnson MP, Adzick NS, Hori S, Howell LJ, Wilson RD, Hedrick H, Flake AW, Crombleholme TM. In utero limb salvage: fetoscopic release of amniotic bands for threatened limb amputation. J Pediatr Surg 2003; 38:848-51. [PMID: 12778379 DOI: 10.1016/s0022-3468(03)00109-x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The natural history of extremity amniotic band syndrome (ABS) is a progression to deformity or amputation. Fetoscopic laser release of amniotic bands in extremity ABS offers the potential to prevent limb amputation. The authors report on 2 patients with isolated extremity ABS who underwent fetoscopic release. Both patients had isolated extremity ABS with compromised extremity perfusion and no other significant structural abnormality diagnosed sonographically. The first patient underwent fetoscopic release of bands of the left wrist, and the second patient underwent lysis of bands around the right wrist and an unsuspected band around the right lower extremity. Both patients had restoration of blood flow by color Doppler to the affected extremity. There were no perioperative complications. In select patients with isolated extremity ABS, early fetoscopic release may prevent amputation and allow improved limb development.
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Johnson MP. The influence of patch demographics on metapopulations, with particular reference to successional landscapes. OIKOS 2003. [DOI: 10.1034/j.1600-0706.2000.880108.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Katz AB, Keswani SG, Zoltick PW, Johnson MP, Crombleholme TM. Placental Adenoviral-Mediated Gene Transfer. Obstet Gynecol 2003. [DOI: 10.1097/00006250-200304001-00163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Hedrick HL, Flake AW, Crombleholme TM, Howell LJ, Johnson MP, Wilson RD, Adzick NS. History of fetal diagnosis and therapy: Children's Hospital of Philadelphia experience. Fetal Diagn Ther 2003; 18:65-82. [PMID: 12576740 DOI: 10.1159/000068075] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Since its inception in 1995, the mission of the Center for Fetal Diagnosis and Treatment at the Children's Hospital of Philadelphia (CHOP) has been to provide comprehensive, multidisciplinary expertise in all facets of prenatal diagnosis, reproductive genetics, and prenatal, perinatal, and postnatal treatment for abnormal fetuses. Most of the authors were trained and/or served on faculty at centers in San Francisco (N.S.A., A.W.F., T.M.C., L.J.H.) or Detroit (A.W.F, M.P.J.). Accurate prenatal detection by serial sonographic study and the development of ultrafast magnetic resonance imaging (MRI) scanners has permitted delineation of the natural history of anatomic malformations. Definition of the pathophysiological features that affect clinical outcome and formulation of management based on prognosis has allowed families to make informed decisions. Outcomes have been improved through carefully planned and coordinated perinatal management. In some cases of life-threatening or severely debilitating defects, prenatal surgery has been offered.
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Johnson MP, Frost NJ, Mosley MWJ, Roberts MF, Hawkins SJ. The area-independent effects of habitat complexity on biodiversity vary between regions. Ecol Lett 2003. [DOI: 10.1046/j.1461-0248.2003.00404.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Coleman BG, Adzick NS, Crombleholme TM, Johnson MP, Howell L, Horii SC, Langer JE, Nisenbaum HL, DeBari S, Iyoob C. Fetal therapy: state of the art. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2002; 21:1257-1288. [PMID: 12418767 DOI: 10.7863/jum.2002.21.11.1257] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
OBJECTIVE To review our experience with the use of sonography in evaluating potential candidates for in utero fetal therapy performed at The Center for Fetal Diagnosis and Treatment at The Children's Hospital of Philadelphia. METHODS This review article was designed to discuss open hysterotomy for the 4 fetal surgical procedures that have been performed at our institution. The procedures included surgical repair of myelomeningocele, resection of sacrococcygeal teratoma in fetuses with nonimmune hydrops, resection of an enlarging congenital cystic adenomatoid malformation that is not amenable to thoracoamniotic shunting, and tracheal clip occlusion for severe left congenital diaphragmatic hernia. RESULTS For each surgical procedure, the use of sonography in the prenatal diagnosis of the congenital anomaly was detailed, as were indications for surgery and surgical procedures, postoperative monitoring and finally delivery, postnatal treatment, and long-term follow-up. Three of the procedures have been reasonably successful with rather dramatic results in some cases such that these techniques are still being performed. The 1 exception was open hysterotomy for the tracheal clip procedure for congenital diaphragmatic hernia, which has been abandoned. CONCLUSIONS Fetal therapy is a rapidly evolving specialty, which is being practiced at several centers in this country. Sonography is an integral part of this specialty practice and has been used extensively in the diagnosis of some congenital anomalies that have debilitating or lethal consequences for the fetus. Technologic improvements in both sonography and magnetic resonance imaging have assisted tremendously in the many advances herein reported in the diagnosis and treatment of the above-described 4 congenital anomalies.
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Abstract
Over the past 40 years, a small but increasing number of fetal genetic and congenital anomalies has become amenable to in utero treatment. Successful fetal therapies have included open procedures for congenital diaphragmatic hernia, cystadenomatoid malformation of the lung and saccrococygeal teratoma, shunts for uropathies and thoracic fluids, pharmacological therapies for congenital adrenal hyperplasia and neural tube defect prevention, and the stem cell treatment of severe combined immunodeficiency disorder.
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Johnson MP, Chamberlain M. Modulation of stress-induced and stimulated hyperprolactinemia with the group II metabotropic glutamate receptor selective agonist, LY379268. Neuropharmacology 2002; 43:799-808. [PMID: 12384165 DOI: 10.1016/s0028-3908(02)00142-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
It is well recognized that glutamate is an integral excitatory neurotransmitter in the neuroendocrine control of several hormonal factors. While the ability of pharmacological agents acting at ionotropic glutamate receptors to modulate the levels of serum prolactin levels has been investigated, there have been few reports of the effects mediated by the G-protein coupled, metabotropic glutamate (mGlu) receptors. The present work was undertaken to investigate the role of the Group II mGlu receptors, mGlu2 and mGlu3 in the regulation of serum polactin levels. LY379268, a Group II selective agonist, did not alter basal levels of circulating prolactin in young (36-40 day old) male rats. However, when an immobilization stress-induced hyperprolactinemia was examined, 10 mg/kg s.c. of LY379268 significantly lowered serum prolactin levels. Similarly, pretreatment with LY379268 was able to reverse the hyperprolactinemia induced with the catecholamine synthesis inhibitor, alpha-methyl-p-tyrosine (aMPT). This inhibition of hyperprolactinemia could be prevented by pretreatment with LY341495, a Group II mGlu receptor antagonist. The Group II antagonist alone had no effect on either basal nor stimulated prolactin levels. The agonist LY379268 was able to prevent the transient hyperprolactinemia associated with stimulation of serotonin 5-HT2A receptors by 2,5-dimethoxy-4-iodoamphetamine (DOI), but did not alter the high levels of circulating prolactin induced with the D2 antagonist, haloperidol. When treatment with LY379268 was delayed until 1 h after aMPT, a time demonstrated to show a full effect of aMPT on serum prolactin levels, the Group II agonist was similarly able to reverse hyperprolactinemia, suggesting LY379268 did not act by preventing the partial catecholamine depletion by aMPT. Similarly, high doses of amphetamine, a dopamine (DA) releaser, were able to reverse the aMPT-induced hyperprolactinemia, consistent with sufficient levels of dopamine remaining after aMPT treatment to modulate prolactin levels. LY379268 did not alter the hyperprolactinemia seen in estrogen-primed, ovariectomized female rats. Taken together the results indicate that stimulation of mGlu2/3 has an indirect inhibitory action on pituitary prolactin release. It is speculated that disinhibition of tubero-infundibular DA release by presynaptic Group II mGlu receptors located on inhibitory inputs to the arcuate hypothalamic nucleus is a possible explanation for the findings.
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