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Dive into the research topics where John B. Lopoo is active.

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Featured researches published by John B. Lopoo.


Prenatal Diagnosis | 1998

Fetal liver position and perinatal outcome for congenital diaphragmatic hernia

Craig T. Albanese; John B. Lopoo; Ruth B. Goldstein; Roy A. Filly; Vickie A. Feldstein; Peter W. Calen; Russell W. Jennings; Jody A. Farrell; Michael R. Harrison

Despite advances in postnatal care, patients born with a congenital diaphragmatic hernia (CDH) suffer substantial morbidity and mortality. The present study was undertaken to determine the prognostic influence of prenatally‐diagnosed liver herniation in the hemithorax in fetuses with CDH.


Journal of Pediatric Surgery | 1999

One-stage correction of high imperforate anus in the male neonate

Craig T. Albanese; Russell W. Jennings; John B. Lopoo; Barbara Bratton; Michael R. Harrison

PURPOSE The aim of this study was to examine the feasibility, safety, and short-term outcome of complete one-stage repair of high imperforate anus in the newborn boy. METHODS A retrospective review was conducted of five full-term male infants who underwent posterior sagittal anorectoplasty without a colostomy within the first 48 hours of birth. Preoperative imaging was performed to assess associated anomalies. All infants underwent cystoscopy before the perineal operation to determine the level of the urinary tract fistula, if present. After completion of the anoplasty, all were turned supine and the colon irrigated free of meconium. Follow-up ranged from 10 to 24 months. RESULTS Laparotomy was not required for any patient. Three patients had a rectoprostatic urethral fistula, one a rectovesical fistula, and one no fistula (common wall at level of prostate). Tapering rectoplasty was required for only the one patient with a rectovesical fistula. There were no intraoperative complications. All patients passed stool within 12 hours after operation and took full feeding by 48 hours. The average hospital stay was 7 days. Postoperative and stenosis occurred in one patient secondary to parental noncompliance with the postoperative dilation regimen. There were no perineal wound complications. All patients have a strong urinary stream and defecate spontaneously without the aid of oral medication or rectal stimulation or enemas. CONCLUSIONS One-stage repair of high imperforate anus in the male neonate is feasible without short-term genitourinary or gastrointestinal morbidity. Whether it is preferable compared with a delayed (two or three stage) repair depends on ultimate long-term anorectal function, which cannot be assessed for several years.


Fetal Diagnosis and Therapy | 2000

Cord Ultrasonic Transection Procedure for Selective Termination of a Monochorionic Twin

John B. Lopoo; Bettina W. Paek; Geoffrey A. Maichin; Gerald S. Lipshutz; Russell W. Jennings; Diana L. Farmer; Per L. Sandberg; Vickie A. Feldstein; Roy A. Filly; Jody A. Farrell; Michael R. Harrison; Craig T. Albanese

Placental vascular communications can present a life-threatening problem in monochorionic twins when one fetus has a lethal anomaly. Although selective feticide is the best option for salvaging the normal twin, techniques normally employed (i.e. intracardiac potassium, air embolism) are not prudent given the common circulatory system. Furthermore, in monoamniotic, monochorionic twin gestations it is important to transect the umbilical cord completely to prevent entanglement of the dead fetus around the cord of the normal twin. We present two cases of monochorionic twins in which the cords were transected with a harmonic scalpel under ultrasonic guidance via one trocar. The harmonic scalpel is an instrument which can simultaneously coagulate and cut blood vessels or tissues. The cord ultrasonic transection procedure is a novel, minimally invasive technique which offers several advantages over the methods currently used for selective feticide in discordant monochorionic twin gestations.


Plastic and Reconstructive Surgery | 1999

A long-term, controlled-outcome analysis of in utero versus neonatal cleft lip repair using an ovine model

Eric J. Stelnicki; Steve K. Lee; William Y. Hoffman; John B. Lopoo; Robert D. Foster; Michael R. Harrison; Michael T. Longaker

Successful open repair of a cleft lip in utero has the advantage of scarless wound healing in the fetus. Unfortunately, no long-term outcome studies have been performed to evaluate the efficacy of these repairs. Moreover, no study to date has compared the long-term results of an in utero cleft lip repair to a similar, control-matched, newborn cleft repair. This study was performed to evaluate the 9-month outcome of in utero cleft lip surgery compared with an identical cleft lip repair performed on infant lambs. In utero epithelialized cleft lips were created through an open hysterotomy in sixteen 65-day-old fetal lambs (term = 140 days) using methods described by Longaker et al. Eight of 16 animals underwent subsequent in utero repair of these clefts at 90 days gestational age. The repair of the remaining eight animals was delayed until 1 week postpartum. At 9 months, the animals were analyzed for changes in lip contour and for the degree of scarring by hematoxylin and eosin and Massons trichrome collagen staining. Two animals in each group died from preterm labor. Of the animals that survived to term, all repaired lips had some degree of abnormality postoperatively. One of six lips repaired in utero dehisced before delivery. Three of six neonatal repairs dehisced in the first postoperative month. In the remaining animals with intact lip repairs, the vertical lip height on the repaired side was an average of 9 to 12 mm shorter than the normal lip in both the in utero and neonatally repaired animals. Phenotypically, the postnatally repaired animals had more lip distortion and visible notching. Histologically, the in utero repair was scarless and the neonatal repairs had scar throughout the entire vertical height of the lip with an associated loss of hair in this region. Maxillary growth was also evaluated. There was no inhibition of maxillary growth in the animals that underwent in utero cleft lip repair. However, in the neonatal repair group, significant maxillary retrusion was evident. Compared with the cleft side of the maxilla, horizontal growth was decreased by 11 percent (p = 0.01). Compared with the intrauterine repair group, there was a 17-percent decrease in horizontal maxillary width (p = 0.01). Straight-line in utero repair of a cleft lip produces a better long-term result in terms of maxillary growth than a similar repair performed postnatally in the ovine model. There was no diminution in maxillary growth in the animals treated in utero. Histologically, in utero repair of clefts was indeed scarless. However, both lip repairs produced lips that were significantly shorter than their contralateral noncleft sides. This degree of lip shortening would require a secondary lip revision, thereby defeating the purpose of performing an intrauterine repair. Comparisons now need to be made between in utero and neonatal repairs using a Millard-type rotation advancement technique before intrauterine treatment can be considered to be more beneficial than our current treatment modalities.


Journal of Pediatric Surgery | 2000

Slide tracheoplasty for congenital tracheal stenosis: A case report

Gerald S. Lipshutz; Russell W. Jennings; John B. Lopoo; Diana L. Farmer; Michael R. Harrison; Craig T. Albanese

BACKGROUND/PURPOSE A variety of techniques have been used to manage pediatric congenital tracheal stenosis. The authors report the technique of slide tracheoplasty for a child with long congenital tracheal stenosis. METHODS A 2-year-old male presented with a history of stridor with feeding. Bronchoscopy findings showed 50% stenosis from complete cartilaginous rings, extending from 2.5 cm below the vocal cords to 2 cm above the carina. Through a neck incision, the trachea was exposed from the cricoid to both bronchi and transected at the midpoint of the stenosis. The upper trachea was split anteriorly to the area of stenosis just below the cricoid. The lower trachea was split posteriorly in the midline. Posterior dissection allowed sliding and anastomosis of both tracheal segments while the lateral vascular supply was left intact. A brace was placed to maintain cervical flexion, and the patient underwent extubation in the operating room. RESULTS He recovered without complication and was dis charged on postoperative day 4. CONCLUSION Slide tracheoplasty offers several advantages for tracheal reconstruction because it is performed with the native tracheal tissues, can be accomplished through a transverse collar incision, and can repair long stenoses without significant tracheal shortening.


Plastic and Reconstructive Surgery | 1999

Natural history of fetuses with cleft lip

John B. Lopoo; Marc H. Hedrick; Stephen T. Chasen; Leslie Montgomery; Frank A. Chervenak; Ruth B. Goldstein; William Y. Hoffman; Michael R. Harrison; Michael T. Longaker

The prospect of fetal surgery for cleft lip is predicated on our ability to accurately identify fetuses with clefts and exclude those that have associated anomalies. Prenatal ultrasound is currently the most appropriate means with which to do this. We reviewed the ultrasonographic data from two large perinatal referral institutions to determine the natural history of fetuses with cleft lip who may be candidates for fetal surgery. Forty fetuses had a cleft lip diagnosed prenatally by ultrasound. In this group, severe associated anomalies were common (30 of the 40) and multiple (23 of the 40) in a majority of fetuses. Life-threatening anomalies, such as central nervous system and cardiac anomalies, were the most common defects. As a result, many fetuses were aborted therapeutically or died in the perinatal period. Out of 12 surviving fetuses, only six had isolated clefts, and two surviving fetuses, diagnosed with isolated cleft lip, had no defect identified postnatally. This information has important implications for the perinatal management of fetuses with cleft lip and the potential role of fetal intervention.


Developmental and Comparative Immunology | 2003

Ontogenic changes in CD95 expression on human leukocytes: prevalence of T-cells expressing activation markers and identification of CD95-CD45RO+ T-cells in the fetus.

Marcus O. Muench; Eva M. Pott Bärtsch; Jeng Chang Chen; John B. Lopoo; Alicia Bárcena

The ontogeny of the human immune system was studied by analyzing fetal and adult tissues for the presence of various lymphocyte populations and activation/maturation markers. CD95 (fas) was expressed in hematopoietic tissues during the final stages of development of monocytes, granulocytes, NK cells and T cells, but to a much lesser extent on B cells. In the periphery, CD95 expression declined on granulocytes and NK cells. CD95 was expressed at a higher level on CD45RA+ peripheral T-cells in the fetus than in the adult. Contrary to the belief that most fetal T-cells are naïve or resting, a notable number of CD45RO+ T-cells were observed as well as an unique CD95-CD45RO+ population. Activation markers CD25, CD122, CD69 and CD80 were also present on fetal T-cells. These findings indicate that in the initial weeks following thymic maturation, a high frequency of T-cells is activated in the periphery of the fetus.


Journal of Craniofacial Surgery | 1998

The in utero repair of Tessier number 7 lateral facial clefts created by amniotic band-like compression.

Eric J. Stelnicki; William Y. Hoffman; Robert D. Foster; John B. Lopoo; Michael T. Longaker

The purpose of this study was to determine the effectiveness of intrauterine reconstruction of lateral facial clefts caused by surgically simulated amniotic band compression. The authors hypothesized that intrauterine lysis of these bands could: 1) prevent the progression of cleft formation; 2) normalize facial development; and 3) allow for the scarless repair of these lateral atypical facial clefts. In a prospective randomized trial, eight 65-day gestational fetal lambs (term, 140 days) were exposed via a maternal hysterotomy. A Tessier 7 facial cleft was made by applying a 2.0 nylon suture as a constriction band to the growing face. The sutures were attached to the zygomatic arch and looped circumferentially into the oral commissure. Two weeks after surgery, four of eight animals were re-exposed. All four animals developed phenotypic changes consistent with Tessier 7 lateral facial clefts. These animals were treated in utero by 1) excising the synthetic constricting band, and 2) opening the epithelialized edges of the lateral facial clefts and performing a primary repair. At birth, the bands on the four untreated animals were cut. The lambs developed to 3 months of age, at which time they were evaluated anthropomorphically for changes in soft tissue measurements, and histologically using hematoxylin and eosin and Mason trichrome stain for the degree of scar at the repair site. Tessier 7 lateral facial clefts were produced in all the untreated animals. Each developed macrostomia with an average 2.3-cm lateral displacement of the oral commissure and partial maxillary clefting induced by the pressure of the restriction band. No evidence of tissue necrosis, maceration, or ulceration was noted. In contrast, animals treated in utero were phenotypically normal. There was no evidence of macrostomia and all anthropomorphic measurements were symmetrical. No bony clefts were seen on gross examination. Histologically, there was no evidence of scar formation at the site of the cleft repair. These findings suggest that like the standard cleft lip, atypical lateral facial clefts can be repaired successfully in utero without scarring. Furthermore, lysis of a restriction band in utero can prevent the progression of this facial deformity, leading to normal development of the face.


Fetal Diagnosis and Therapy | 2001

Safety of chronic fetal vascular access in the sheep model.

Bettina W. Paek; John B. Lopoo; Russell W. Jennings; Diana L. Farmer; Craig T. Albanese; Michael R. Harrison

Objective: Long-term access to the fetal circulation has the potential to open up new perspectives in the treatment of numerous fetal anomalies. The purpose of this study was to investigate the safety of long-term catheterization of fetal placental vessels. Methods: A midline laparotomy was performed in 4 time-mated pregnant ewes at 125 days’ gestation (term 145 days). Placental vessels were exposed by a small uterine incision. A specially designed catheter was inserted into a placental vessel over a length of 3 cm, the distal end of the catheter was tunneled underneath the maternal skin and attached to a subcutaneous port implanted in the maternal flank. All pregnancies were allowed to go to term. Results: Ewes and fetuses tolerated the placement of the catheter and port without complications. The catheter remained patent in all cases. All lambs were delivered vaginally at term and did not require resuscitation after birth. No fetal anomalies or growth restriction were noted. Conclusion: The ovine placental vessel can be accessed long term without complication.


Fetal Diagnosis and Therapy | 1999

Are Bilateral Fetal Lung Masses Double Trouble

Gerald S. Lipshutz; John B. Lopoo; Russel W. Jennings; Jody A. Farrell; Michael R. Harrison; Craig T. Albanese

Objectives: To examine the perinatal natural history of bilateral fetal cystic lung masses. Methods: The records of a tertiary medical center over a 3-year period were reviewed for cases of fetal bilateral pulmonary masses. Results: Three of 98 fetuses referred for evaluation over a 3-year period from September of 1995 to August of 1998 had bilateral lung lesions. Two of these cases resulted in live births, while one, associated with hydrops, resulted in death after preterm delivery. Conclusions: Similar to prenatally diagnosed unilateral lung lesions, hydropic fetuses with bilateral cystic lung lesions have a poor prognosis. Nonhydropic fetuses, however, may be asymptomatic despite persistent lesions on postnatal CT scan. These observation may prove helpful for prenatal counseling for these rare lesions.

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Roy A. Filly

University of California

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Christoph Brezinka

Innsbruck Medical University

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