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J A Deprest

Publications and source records attributed to J A Deprest.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Minimally invasive techniques make fetal surgery possible. Disabling abnormalities can be corrected].

Increases in our knowledge of the fetus and improved skill in early prenatal diagnosis inevitably result in attempts to treat some of the abnormalities detected. Although most fetal malformations diagnosed prenatally in continuing pregnancies are best managed by medical and surgical intervention after planned delivery, some structural defects may require in utero-treatment to forestall subsequent sequelae. The article consists in a review of the current status of ultrasound-guided invasive fetal therapy, including multifetal pregnancy reduction, manipulation of amniotic fluid, drainage and shunting procedures, fetal transfusion therapy, operative fetoscopy, and in utero stem cell transplantation. Future prospects and developments in this rapidly expanding field are also outlined.

Amniocentesis↗
PubMed1998

Fetal membrane closure techniques after hysteroamniotomy in the midgestational rabbit model.

OBJECTIVE: We studied closure techniques for amniotic access in midgestational rabbits. STUDY DESIGN: Twenty-eight rabbits with a total of 313 amniotic sacs were used for this study. In each animal a 1 cm hysteroamniotomy was made in two amniotic sacs at 22 days' gestation (term = 32). For 12 amniotic sacs (group 1) only the myometrium was closed by microsurgical suturing. In group 2 (n = 12), sutures included myometrium and membranes. In group 3 (n = 8), a collagen plug was placed, and in group 4 (n = 12) fibrin glue was used. Twelve sacs were left unclosed (positive controls) and the unmanipulated 257 sacs were negative controls. Eight days later (gestational age 30 days) amniotic sacs were evaluated for the presence of amniotic fluid, membrane integrity, and fetal weight and survival. Statistics were done with two-tailed Fisher's exact test and one-way analysis of variance. RESULTS: Membrane integrity (p = 0.0036) and amniotic fluid (p = 0.047) were best restored after myometrial closure. Fetal weight and survival rate were not affected by different closure techniques. CONCLUSION: In this model primary closure of the myometrium only yielded best results.

Amnion↗
PubMed1998

The plug-unplug sequence: an important step to achieve type II pneumocyte maturation in the fetal lamb model.

PURPOSE: The purpose of this study was to test the hypothesis that tracheal obstruction (plugging) in the fetal lamb model leads to a decrease in the absolute number of type II pneumocytes and that reversing the obstruction before birth (unplugging), allows the type II cells to recover while maintaining the beneficial effect on lung growth. METHODS: Nine time-dated pregnant ewes (term, 145 days), carrying 17 fetuses, were used in this surgical trial. The fetuses were divided into three experimental groups: group A underwent plugging at 93 days gestation, followed by unplugging at 110 days; group B animals had tracheal ligation at 93 days and group C consisted of unoperated controls. All fetuses were delivered by cesarean section at 136 days' gestation. The fetal trachea was obstructed with the tracheoscopically placed detachable balloon described by our group. Unplugging was performed by needle puncture of the balloon under tracheoscopic vision. Outcome measurements consisted of lung-to-body-weight ratio (LWBR), lung morphometry (mean terminal bronchial density [MTBD] and linear intercept [Lm]), and assessment of the number of type II pneumocytes. The latter was determined by in situ hybridization to the mRNA of surfactant protein-C, which is exclusively produced by type II cells. Statistics were calculated using a two-tailed unpaired t test and P less than .05 is considered significant. RESULTS: Seventeen animals are included in the results. All of them had lung samples analyzed for lung morphometry, whereas for type II cells analysis, three animals were studied in each group. Morphometric analyses were consistent with pulmonary hyperplasia for group B, whereas group A lungs showed more histological maturity than group C albeit not as marked as group B. In group A, there was a similar number of type II cells to that observed in group C (53.2 +/- 3.9 v 55.9 +/- 4.0, P = .66). However, for group B animals, the number of type II pneumocytes was markedly decreased compared with controls (4.7 +/- 0.1 v 55.9 +/- 4, P = .0003). CONCLUSIONS: The authors conclude that tracheal ligation until birth, although inducing pulmonary hyperplasia, significantly decreases the number of type II pneumocytes in the alveoli. After a temporary 15-day occlusion initiated at 95 days' gestation, there is complete normalization of the density of type II cells. These results bear importance on the duration of PLUG to treat the pulmonary hypoplasia seen in congenital diaphragmatic hernia. Temporary tracheal obstruction now needs to be tested in a hypoplastic lung model.

Animals↗
PubMed1998

Single-port tracheoscopic surgery in the fetal lamb.

BACKGROUND/PURPOSE: Endoscopic fetal surgery could help avoid many of the problems associated with open fetal surgery, but the use of multiple ports may be too traumatic to the membranes. The authors describe a single-port technique of tracheoscopic surgery in the fetus. METHODS: Time-dated pregnant ewes (95 to 105 days; term, 145 days) underwent midline laparotomy under general halothane anesthesia. A 5-mm-diameter balloon-tipped cannula was introduced in the uterus by Seldinger technique. A 1.2-mm semirigid mini-endoscope, fitted inside a 9F, 20 degrees curved sheath, was introduced under continuous, low-pressure irrigation, inside the fetus' mouth, and advanced into the trachea. RESULTS: Endotracheal procedures, including temporary (n = 11) and permanent balloon tracheal occlusion (n = 30) and placement of a barbed guide wire for endotracheal occlusion device insertion (n = 12), were performed by introducing a 1-mm diameter instrument alongside the telescope. These were successfully performed in 52 of the 53 fetuses. The rigidity of the telescope allowed controlled access to the pharynx; its curve allowed full tracheobronchial endoscopy with the fetus in utero. CONCLUSIONS: The present technique marries the control and optical quality of a rigid endoscope with the physiological curve only a flexible instrument could offer until now. The types of procedures performed with this technique illustrate its potential as a research tool; the size (1.2-mm diameter), shape, and optical qualities of the telescope should make clinical applications possible.

Animals↗
PubMed1998

Experience with fetoscopic cord ligation.

OBJECTIVE: In the case of a monochorionic multiple pregnancy with one non-viable fetus who compromises its co-twin, fetoscopic cord ligation may be performed. We describe our fetoscopic cord ligation technique and discuss the efficacy of cord ligation for salvaging the co-twin, based on available data. STUDY DESIGN: Descriptive case series of four cases and review of the cases published up to 1996. RESULTS: We performed four successful ligations. Of the 23 reported cases, which include the present series, two ligations failed. Four fetuses died in utero, and 17 were born alive at a mean of 8 weeks following the procedure. Two babies died in the perinatal period, a third after 60 days. Preterm uterine contractions do not seem to be a clinical problem. Preterm prelabour rupture of the membranes (PPROM) complicates about 40% of cases, the majority occurring prior to 32 weeks. CONCLUSION: Fetoscopic cord ligation is a feasible procedure with a 71% survival rate and a high risk for PPROM.

Adult↗
PubMed1998

Tracheoscopic endoluminal plugging using an inflatable device in the fetal lamb model.

OBJECTIVE: Intra-uterine tracheal occlusion has been proposed to reverse pulmonary hypoplasia, an important prognostic factor in congenital diaphragmatic hernia. We aimed to evaluate the feasibility and pulmonary effects of tracheoscopic tracheal obstruction with a detachable balloon. STUDY DESIGN: Fourteen mid-trimester fetuses out of 24 in 13 ewes underwent tracheoscopic balloon obstruction. Ten non-operated fetuses served as controls. Plugging was performed under fiber-tracheoscopy using a detachable balloon. Outcome measures consisted of: total operating time, tracheoscopy time, fetal survival, efficiency of plugging, and pulmonary effects. The Mann-Whitney test and linear regression were used for statistical analysis. RESULTS: Mean operating time and tracheoscopy time were 65+/-12 and 6.6+/-3.9 min, respectively. One intra-operative death occurred in each group. The post-operative mortality was 2/13 for cases and 2/9 for controls. In all 14 fetuses, the trachea was successfully obstructed. In the 11 treated animals born alive, the lung-to-body-weight ratio was 0.060+/-0.01, while in controls it was 0.031+/-0.01 (P = 0.0001). In a subset of six fetuses obstructed for 14-18 days, mean-terminal-bronchial density was 0.95+/-0.59, compared to 2.06+/-0.80 for controls (P = 0.046). CONCLUSIONS: Using fetal tracheoscopy, the trachea can successfully be obstructed with an inflatable balloon. Pulmonary hyperplasia is achieved when the obstruction lasts 2 weeks.

Animals↗
PubMed1998

Alternative technique for Nd: YAG laser coagulation in twin-to-twin transfusion syndrome with anterior placenta.

Nd: YAG laser coagulation is used to treat severe twin-to-twin transfusion syndrome (TTS). Success of the technique depends on visualization of the placenta, the fetal membranes and the targeted vessels, as well as obtaining an optimal inclination angle for laser coagulation. In the rare case of an extensive anterior placenta, it may be difficult to achieve these conditions using the percutaneous approach. Here, we propose an alternative to the percutaneous procedure. Modifications involve an open access and the use of a flexible cannula and bent scope. An extraplacental area, usually at the fundus, is identified by B-mode and color Doppler imaging. A mini-laparotomy is made under general anesthesia. The viscera are retracted and the cannula is inserted under direct view and ultrasound control by the Seldinger technique. The curved fiberscope is passed through the flexible cannula, allowing adequate inspection of the placenta, and target vessels can be coagulated at an angle close to 90 degrees. After the procedure, the uterus is closed primarily to prevent postoperative leakage of amniotic fluid or hemorrhage. This technique has been successfully used in six patients with TTS and a completely anterior placenta, with a gestational age between 18.5 and 22.0 weeks. In all patients, the amniotic cavity was accessed without hemorrhage. The outcomes are similar to those published previously for laser coagulation. The mean interval from intervention until delivery was 10.5 weeks. All 12 fetuses were live born but four died from complications of extreme prematurity. No maternal complications occurred.

Female↗
PubMed1997

Tracheoscopic endotracheal occlusion in the ovine model: technique and pulmonary effects.

BACKGROUND/PURPOSE: The purpose of this study was to assess the tracheoscopic placement of a detachable balloon to obstruct the trachea in the fetal lamb model and to study the pulmonary effects 2 weeks later. METHODS: Thirteen pregnant ewes carrying 27 fetuses were used in this trial. Thirteen fetuses underwent endotracheal plugging at a mean gestational age of 95 (90 to 100) days (term, 145). Fourteen nonoperated fetuses served as controls. The intended duration of obstruction was 15 days. Study parameters consisted of operating time, fetal survival, performance of the balloon, and pulmonary changes. RESULTS: Hysterotomy time was 41 +/- 25 minutes and tracheoscopy time was 7.2 +/- 3.4 minutes. There were no intraoperative deaths in this series. Postoperative fatalities occurred in 2 of 13 plugged fetuses and 1 of 14 controls. At completion of the experiment, the balloon was recovered intact in the trachea of 12 of 13 (92.3%) fetuses. The lung weight/body weight ratio was 76 +/- 16 mg/kg for plugged animals, while in controls it was 34 +/- 8 mg/kg (P = .0001). The lung volume/body weight ratio was 101 +/- 17 mL/kg in plugged fetuses, compared with 47 +/- 4 mL/kg for controls (P = .0002). Mean-terminal-bronchial-density was 0.937 +/- 0.303 for plugged animals, compared with 1.911 +/- 0.441 for controls (P = .0002). Mean linear intercept was 60.9 +/- 5.2 microm in treated fetuses, and 46.3 +/- 5.8 microm for controls (P = .0004). CONCLUSIONS: Fetal endotracheal occlusion, using a tracheoscopically placed detachable balloon, is reliable, and results in pulmonary hyperplasia after 2 weeks of obstruction. This technique may be beneficial in treating the pulmonary hypoplasia seen in congenital diaphragmatic hernia. Further studies using this balloon device are now required to corroborate these findings.

Abnormalities, Multiple↗
PubMed1997

Access techniques in endoscopic fetal surgery.

Endoscopic surgery may in the future become an attractive alternative to open fetal surgery. Herein, we present our evolving experience with minimal access techniques in sheep and nonhuman primate models. Fifty-two pregnant sheep (term = 145 d) were used. All underwent laparotomy. Cannulas were 5 mm diameter with balloon fixation device. In group I (95-105 d, n = 22, and 70-74 d, n = 19), a total of 119 cannulas were placed by open hysterotomy and pursestring suture through myometrium and membranes. In group II (n = 11), access was obtained by Seldinger guidewire technique. Eight cannulas were introduced over a dilator and 7 were radially expanding endoscopic cannulas. Fifteen cannulas were also placed in 5 pregnant Rhesus monkeys using Seldinger and radially expanding techniques. Cannula removal was followed by insertion of a collagen sponge plug and oversewing of the myometrium. Mini-hysterotomies with purse-stringing provided excellent access to the amniotic cavity, without dissection of the membranes. Classic Seldinger technique with forward dilatation was equally effective, but caused stretching of membranes. In sheep and in primates, Seldinger technique with radial dilatation allowed safe access without membrane separation. Leak-proof removal of the cannulas was achieved in all primates. Open hysterotomy with purse-string and balloon-tipped cannula provides efficient and safe access to the gravid sheep uterus. Seldinger technique allows equally secure access, and alleviates the need for hysterotomies. Radial dilatation of the porthole eliminates forward dissection of the membranes, both in sheep and primate models. This method, and collagen plug insertion upon completion of the endoscopic procedure, may provide a truly minimally invasive approach to in-utero surgery.

Animals↗
PubMed1997

Intrauterine tracheal obstruction, a new treatment for congenital diaphragmatic hernia, decreases amniotic fluid sodium and chloride concentrations in the fetal lamb.

OBJECTIVE: To evaluate the effect of fetal tracheal occlusion on sodium and chloride concentrations in amniotic and tracheal fluid. SUMMARY BACKGROUND DATA: Intrauterine tracheal occlusion has been proposed to reverse pulmonary hypoplasia, an important prognostic factor in congenital diaphragmatic hernia. In early human trials, technical failure of the obstructive device has been reported. METHODS: Eight fetal lambs (gestational age = 95 days) were subjected to fetal tracheoscopy, and amniotic and tracheal fluid samples were taken. In multiple pregnancies (n = 6), amniotic fluid was also sampled from the contralateral amniotic sac and used as a control. Subsequently, endotracheal obstruction, using a detachable balloon, was performed. After 14 days, all fetuses were delivered, and sodium and chloride concentrations in amniotic and tracheal fluid were measured again. Statistical analysis was done using a two-tailed Student's t test, paired or unpaired as appropriate. RESULTS: In controls, between 95 and 109 days gestational age, no significant changes occurred in sodium or chloride concentrations in amniotic or tracheal fluid. After 2 weeks of tracheal obstruction, however, chloride and sodium concentrations in amniotic fluid decreased (chloride = 76.7 mEq/L vs. 107.6 mEq/L, p = 0.0003; sodium = 109.6 mEq/L vs. 125.9 +/- 5.2 mEq/L, p = 0.019). A concomitant increase in chloride and sodium concentration was observed in tracheal fluid (chloride = 145.4 mEq/L vs. 130.0 mEq/L, p = 0.047; sodium = 153.1 mEq/L vs. 142.9 mEq/L, p = 0.051). When comparing groups at 109 days, chloride and sodium concentrations in amniotic fluid were markedly lower in the treated group versus controls (p = 0.0004 and p = 0.05 for chloride and sodium, respectively). CONCLUSION: Complete tracheal occlusion in ovine fetuses results in a significant decrease of amniotic fluid sodium and chloride concentrations.

Amniotic Fluid↗
PubMed1997

Operative fetoscopy: new perspective in fetal therapy?

In a limited number of conditions in utero surgery may be life-saving, such as some cases of congenital diaphragmatic hernia, cystic adenomatoid malformation of the lung, sacrococcygeal teratoma and lower urinary tract obstruction. Postoperative premature labour and its extreme invasiveness have been major drawbacks for open fetal surgery. More recently the merger of fetoscopy and advanced video-endoscopic surgery has been the basis of the concept of endoscopic fetal surgery. In order to evaluate the opportunities of 'fetendo' surgery, animal models have been developed to test the safety of the endoscopic approach, and the feasibility of surgical manipulations on the fetus. In the non-human primate, a lesser invasiveness of endoscopy over open surgical approach was demonstrated, by a significant decrease in uterine activity in comparison with hysterotomy. The main application of fetoscopy today is the surgical treatment of complicated or abnormal monochorionic twin gestations. Fetoscopic laser coagulation of chorionic plate vessels is suggested as a causal therapy for severe feto-fetal transfusion syndrome. Survival rates are around 55 per cent with an incidence of five per cent of neurological morbidity. Fetoscopic cord ligation is associated with a 66 per cent survival rate, but unfortunately also with a risk of 30 per cent for PPROM prior to 32 weeks. Although still in its early experimental phase, endoscopy seems to offer new hope for surgical fetal therapy. Though conceptually very tempting, the development of endoscopic fetal surgery should follow the formal guidelines, as earlier formulated for open surgery by the International Fetal Medicine and Surgery Society. The prospective registration of worldwide experience is advocated and a randomized trial of laser therapy versus amniodrainage is announced.

Animals↗
PubMed1996

The effect of open and endoscopic fetal surgery on uteroplacental oxygen delivery in the sheep.

Open fetal surgery predictably results in postoperative uterine contractions and often in premature labor, but its intraoperative effects on the uterus are not known. In 10 pregnant ewes (108 to 115 days' gestation), uterine artery flow, uterine venous oxygen saturation, arterial saturation, and uterine electromyography were recorded simultaneously (control). Six ewes underwent a stapled hysterotomy, and four underwent placement of three endoscopic surgery cannulas and amnioinfusion. Uterine contractions were present 52% of the time (range, 34% to 72%), and there was no significant difference between control, hysterotomy, and endoscopic access. Uterine artery blood flow and uteroplacental oxygen delivery at rest decreased (to 73% of control) after hysterotomy (P < .05), but not after endoscopy. Fetal + uteroplacental oxygen consumption did not differ significantly between the groups. In conclusion, (1) uteroplacental oxygen delivery after hysterotomy alone decreased to levels critical for adequate fetal oxygenation; (2) endoscopy did not alter uteroplacental oxygen delivery; and (3) during open fetal surgery, further oxygen demand/delivery mismatch is likely, by traction on uterine and umbilical vessels and fetal stress.

Analysis of Variance↗
PubMed1996

Enterocele as a consequence of laparoscopic resection of deeply infiltrating endometriosis.

Laparoscopic excision of deeply infiltrating endometriosis in the cul-de-sac or the rectovaginal septum by means of electrosurgery or laser is performed frequently. Little is known about the long-term results or complications of this surgery. We suggest that enterocele could be a complication of the procedure. A patient developed a large enterocele 3 years after a laparoscopic excision of a deep endometriotic nodule with resection of the uterosacral ligaments. We question whether routine preventive measures should not be taken after excision of a deep endometriotic nodule from the rectovaginal septum.

Adult↗
PubMed1995

Intrauterine endoscopic creation of urinary tract obstruction in the fetal lamb: a model for fetal surgery.

OBJECTIVE: Our purpose was to evaluate the feasibility of intrauterine endoscopic fetal surgery in a fetal lamb model by creating a urinary tract obstruction. STUDY DESIGN: Lower urinary tract obstruction was created by ligation of the urethra and urachus in 21 fetal lambs, eight at 95 to 105 days' gestation (term 145 days) and 13 at 70 to 75 days. The endoscopic approach consisted of a 0-degree 5 mm telescope, three 5 mm cannulas, uterine distention by amnioinfusion, and adapted instrumentation. Intrauterine fetal monitoring included temperature and pulse oximetry registration. RESULTS: In 20 cases the urachus could be identified and ligated inside the umbilical cord. The urethra was ligated in the anterior abdominal wall (n = 7) or obstructed at the level of the penis (n = 13). Mean fetal heart rate was 147 +/- 35 beats/min, and fetal temperature at the end of intervention was 38.14 degrees +/- 2.1 degrees C. The overall postoperative survival rate was 76%. CONCLUSION: Urinary tract obstruction can be created endoscopically in the fetal lamb. This operation can serve as a model for endoscopic fetal surgery.

Animals↗
PubMed1995

Gasless laparoscopy in infants: the rabbit model.

Laparoscopic operations can be performed in neonates and infants, but carbon dioxide pneumoperitoneum may be more dangerous than in adults. Therefore the concept of gasless laparoscopy is especially attractive for small children. The authors have developed an animal training model of gasless infant laparoscopy using the rabbit. Eleven New Zealand white rabbits (mean weight, 2.2 kg) were premedicated with fentanyl (10 micrograms intramuscularly) and maintained under inhalation anesthesia by mask, with halothane (1.0 to 2.5%) in oxygen and nitrous oxide (1:1). The animals were neither intubated nor mechanically ventilated. Heart rate and oxygen saturation were monitored by pulse oximetry. A supraumbilical incision was made through the peritoneum, and an abdominal wall elevator was inserted. A 4-mm-diameter 30 degrees endoscope was introduced at the same site, allowing excellent visualization of the abdominal cavity. Three additional 5-mm cannulas were placed, and a standard Nissen fundoplication was performed in all 11 animals. In seven of these, a left nephrectomy was also performed. Five-millimeter pediatric instruments and 1.7- and 2.7-mm laryngoscopic instruments were used. The rabbit can serve as a training model for laparoscopy in the infant. Gasless laparoscopy, using abdominal wall elevation, may be particularly useful in very small patients.

Abdominal Muscles↗
PubMed1995

Review on laparoscopic hysterectomy.

An increasing number of data on laparoscopic hysterectomy has become available since the procedure was introduced in 1989. This article reviews all published series till June 1995, totaling 4502 cases. Prior to this procedural evaluating strategy is addressed to highlight the short-comings of such a review. Most data are collected retrospectively in a lunited number of centers, all dedicated to the procedure. Laparoscopy Assisted Vaginal Hysterectomy (LAVH) may cover a whole range of procedures, and a classification system is needed. It is suggested that classification systems based on the degree of anatomical dissection is clinically most relevant. During 76.1% of LAVH-procedures, the uterine artery is ligated laparoscopically, though the fraction of total laparoscopic hysterectomies is minimal (1.5%). Mean conversion rate is 2.5% and mean major complication rate is 3.24% (range 0-20%). Urinary tract lesions (1.42%), such as bladder perforation, and reintervention for haemorrhage (0.78%), are the most frequent complications. LAVH seems an efficacious procedure, more data on its effectiveness are urgently needed.

Female↗