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At least 127 records · Page 7Linked to original sources
PubMed1996

Percutaneous access to the uterus for fetal surgery.

In utero repair of selected life-threatening malformations in the human fetus is now a clinical reality, yet fetal surgery continues to pose significant risks to both the mother and the unborn child. Preterm labor is a major problem directly related to the large uterine incision required for fetal exposure. Using technology developed for laparoscopic surgery, we have devised instruments and techniques to perform fetal endoscopic surgery. We now report a percutaneous technique for direct endoscopic access to the uterus. Minimally invasive fetoscopic surgery may expand the indications for fetal surgery by decreasing fetal risks, facilitating intervention earlier in gestation, and reducing preterm labor. This technique was developed in 4 fetal lambs who underwent endoscopic intervention at 105-110 days gestation (term = 145 days). Under ultrasound guidance, a 20-gauge spinal needle was advanced through the maternal abdomen, uterus, and directly into the amniotic cavity. Warmed saline was infused through the needle to expand the amniotic cavity. Next, a 5-mm balloon-tipped trocar was placed percutaneously with ultrasound guidance into the amniotic cavity. A 5-mm laparoscope was introduced and under endoamniotic vision two more 5-mm trocars were percutaneously placed. In all four sheep a 5-mm trocar was placed percutaneously into the gravid uterus. The most difficult step was puncturing through the amniotic membranes, but the sharp tip of the trocar facilitated getting into the amniotic cavity. Excellent visualization of the fetus was obtained with minimal uterine trauma. We have developed a fetoscopic technique in sheep for percutaneous placement of trocars into the uterus using ultrasound guidance. This approach allowed excellent visualization of the fetus with significantly less uterine trauma than open fetal surgery and is an essential prerequisite for future fetal endoscopic interventions.

Animals↗
PubMed2003

Fetal cystoscopy in the management of fetal obstructive uropathy: experience in a single European centre.

OBJECTIVE: To audit diagnostic and therapeutic fetal cystoscopy for suspected posterior urethral valves (PUV). METHODS: In 13 fetuses, (14-28 weeks) the bladder was entered with a 1.3 mm embryo-fetoscope and intravesical findings documented. In 10 fetuses, an attempt was made to treat the obstruction by saline hydro-ablation (n = 4) and/or guide-wire passage (n = 9). Renal function was assessed post-natally at 10 to 34 months. RESULTS: The bladder wall was visualised in 12/13 cases and the bladder neck in 11; in 10 cases the upper urethra was entered, and the obstruction visualised in five. PUV were 'seen' in 4/9 confirmed cases, but also in one case of urethral atresia, while in two others the degree of resistance to guide-wire passage suggested atresia or prune belly. Therapeutic attempts were technically successful, at least initially, in 6/10 cases. Of the five cases with confirmed PUV and normal fetal urinary electrolytes, two have acceptable renal function at follow-up. Hydro-ablation in one case resulted in resolution of sonographic signs of obstruction, and ablated valves were confirmed post-natally. CONCLUSIONS: Semi-rigid fetal cystoscopy allows entry into the upper urethra in most obstructive uropathies, although bladder neck angulation precludes visualisation of the site of obstruction in the majority. Guide-wire passage or hydro-ablation may allow relatively atraumatic ablation of PUV in utero without the chronic bladder decompression associated with vesico-amniotic shunting. However, current technical limitations need to be overcome, possibly by the use of flexible or angled fetoscopes, before the role of cystoscopic treatment can be formally evaluated.

Cystoscopy↗
PubMed2005

Fetal transesophageal echocardiography: clinical introduction as a monitoring tool during cardiac intervention in a human fetus.

Because of insufficient imaging by maternal transabdominal fetal echocardiography (TAE) in a human fetus with aortic atresia, imperforate atrial septum and progressive cardiac failure, we assessed the feasibility of fetal transesophageal echocardiography (TEE) as a monitoring tool during fetal cardiac intervention at 24 + 6 weeks of gestation. Percutaneous fetoscopic intraesophageal deployment of the ultrasound catheter was achieved and did not result in any maternal or fetal complications. Fetal TEE permitted substantially clearer definition of fetal cardiac anatomy and intracardiac device manipulations than conventional maternal TAE. Despite the employment of various devices, no sufficiently large opening could be achieved within the atrial septum. Although the fetus tolerated the procedure remarkably well and satisfactory fetoplacental flow could be documented at the end of the procedure, the fetus died from progressive cardiac failure 3 days after the intervention. Fetoscopic TEE is feasible in the human fetus and permits substantially clearer definition of fetal cardiac anatomy and intracardiac manipulations than conventional maternal TAE. Based on the observation of spontaneous closure of multiple iatrogenic perforations of the atrial septum, specialized devices are required in order to improve the technical success rate of septoplasty methods and hence the survival odds of these high-risk patients.

Adult↗
PubMed1989

Neodymium:yttrium-aluminum-garnet laser occlusion of rhesus placental vasculature via fetoscopy.

We tested the feasibility of photocoagulating placental vascular communications with a fetoscopically delivered neodymium:yttrium-aluminum-garnet laser in 12 pregnant monkeys in the second trimester. The technique was successful in eight cases. One ended in spontaneous labor 2 weeks after occlusion and one stillbirth occurred at term. Six live fetuses were delivered at term, with all treated vessels demonstrating occlusion. There was minimal placental damage at the laser impact sites, and no fetal abnormalities were detected. Long-term occlusion of placental vasculature can be accomplished by fetoscopically delivered laser energy.

Animals↗
PubMed2005

Invasive antenatal interventions in complicated multiple pregnancies.

Multiple pregnancies still pose challenging problems for modern medicine. Complications in monochorionic multiple pregnancies have sparked a revival of fetoscopy as a means surgery on the placenta and umbilical cord. As such, fetoscopic laser coagulation is currently the best first-line treatment for severe twin-to-twin transfusion syndrome. Also, fetoscopic or ultrasound-guided cord coagulation seems to be an effective technique for selective feticide in monochorionic twins, albeit with still considerably higher fetal loss rates compared with selective feticide by potassium chloride injection in dichorionic twins.

Chorion↗
PubMed2003

Fetal surgery for sacrococcygeal teratoma.

A great deal has been learned regarding the natural history and pathophysiology of fetal SCT. The logic behind fetal intervention for SCT and hydrops appears to be correct, and open and minimal access techniques of fetal intervention have been shown to be feasible. The development of fetal intervention for SCT has mirrored those developed for other diseases such as congenital diaphragmatic hernia. In a recent presentation, Harrison, the original pioneer in fetal surgery, outlined trends in fetal intervention. The first trend is that of moving from open, invasive techniques to minimally invasive techniques. In the case of SCT surgeons are moving from open resection to RFA and possibly to fetoscopic resection. The second trend outlined by Harrison is a movement away from total in utero repair of a defect that recapitulates postnatal treatment and toward manipulation of fetal pathophysiology to reverse life-threatening events. In SCT surgeons employ RFA to ablate causative blood vessels to reverse fetal hydrops with the knowledge that these fetuses will require postnatal resection of the tumor. In contrast to resection, RFA requires less time and significantly less maternal morbidity than open resection. Further study is required to determine the role of minimal access techniques in SCT. Future directions for treatment of fetal SCT with hydrops might include fetoscopic resection or high-intensity ultrasound ablation.

Female↗
PubMed2001

Controlled fetal blood-letting of the recipient twin as a new method for the treatment of severe twin-twin transfusion syndrome: preliminary results.

OBJECTIVE: To investigate the feasibility of withdrawal of blood from the recipient twin as a new method for the treatment of severe twin-twin transfusion syndrome. METHODS: Seven consecutive monozygotic monochorionic twin pregnancies affected by severe twin-twin transfusion syndrome were treated. Fetal blood was withdrawn from the recipient twin using cordocentesis. The volume of blood to be removed was determined using the formula for intrauterine blood transfusion of anemic fetuses. Fetal outcome was evaluated in relation to changes in the amniotic fluid and in growth curves (comparing the differences between the centiles of the estimated fetal weight before the procedure and the centiles of weight at birth), fetal mortality, gestational age at delivery, neonatal weight and neurological damage. RESULTS: Overall, seven of the 14 (50%) fetuses survived; at least one fetus survived in five (71%) pregnancies, both fetuses survived in two (29%) pregnancies, while in two (29%) pregnancies there were no survivors. No maternal complications were observed. At follow-up, one (14%) baby had minor neurological damage. CONCLUSIONS: Withdrawal of blood from the recipient twin in the treatment of severe twin-twin transfusion syndrome was associated with survival similar to that of the alternative techniques of serial amniodrainage and fetoscopic laser surgery, with some possible advantages such as reduced neurological damage compared with serial amniodrainage. It is also less invasive compared with fetoscopic laser surgery.

Cordocentesis↗
PubMed1999

Prognostic factors in severe twin-twin transfusion syndrome treated by endoscopic laser surgery.

OBJECTIVE: The aim of this study was to investigate clinical and sonographic parameters, in particular Doppler blood flow measurements, in severe second-trimester twin-twin transfusion syndrome before and after endoscopic laser coagulation of the placental vascular anastomoses, to correlate these data with fetal outcome and to determine whether fetal blood flow measurements could help to estimate the probability of fetal survival. METHODS: In 121 cases of severe twin-twin transfusion syndrome examined between 17 and 26 weeks of gestation, the following investigations were performed: fetal biometry, placental location, deepest pool of amniotic fluid, echocardiography and Doppler sonography of the umbilical arteries and the ductus venosus of both twins before and after fetoscopic laser ablation of the placental anastomoses. RESULTS: The overall survival rate was 64% (156/242). Both fetuses survived in 48% (58/121) and one fetus survived in 33% (40/121), resulting in 81% (98/121) of pregnancies with at least one survivor. Gestational age at the time of the procedure and placental location had no significant influence on fetal survival. The amniotic fluid volume drained after laser coagulation correlated significantly (p = 0.038) with the risk of miscarriage or extremely premature delivery within 4 weeks of the procedure. Intertwin discrepancy in abdominal circumference showed a significant negative correlation (p = 0.004) with the probability for survival of donor fetuses. Before the procedure, 19% (23/121) of donor twins and 5% (6/121) of recipient twins showed absent or reversed end-diastolic flow in the umbilical artery (p = 0.001). This finding had no significant influence on the survival rate of donors. An increase of waveform indices in the umbilical artery 1 day after the procedure compared to immediately after the procedure correlated significantly with a lower probability for survival of donors (p = 0.042) and recipients (p = 0.018). Before the procedure, 37% (45/121) of recipient twins and 9% (10/113) of donor twins showed absent or reversed flow during atrial contraction in the ductus venosus (p < 0.0001). This finding had a significant negative influence on the survival rate of recipient fetuses (p = 0.02). Furthermore, an increase of waveform indices in the ductus venosus 1 day after the procedure compared to immediately after the procedure correlated significantly with a lower probability of survival in recipients (p = 0.005). CONCLUSIONS: Fetoscopic laser coagulation of the placental vascular anastomoses in severe mid-trimester twin-twin transfusion is a potentially corrective and effective, minimally invasive procedure. Doppler investigation of the umbilical and fetal circulations provides important information on the fetal condition, prognosis and therapeutic effects of the intervention. Signs of congestive heart failure in the recipient may reduce the probability of survival, whereas increased placental resistance in the donor before the procedure is not necessarily associated with a reduction in the probability of survival after laser coagulation.

Arteriovenous Anastomosis↗
PubMed1977

[Fetoscopy under ultrasound control (author's transl)].

Under local anaesthesia and ultrasound control (beta-mode; Vidoson) the fetoscope was introduced into the amniotic cavity in 23 women, 13-20 weeks pregnant. Used before planned surgical abortion the method decisively reduced the dangers of damage to the fetus. In 21 women introduction of the fetoscope was without problem, but twice obesity made it difficult. Placental surface, umbilical cord, fetal head and fetal limbs were more commonly seen than other fetal parts. In one instance fetoscopy made it possible to exclude Mohr's syndrome. Preliminary attempts to obtain fetal blood by puncture of placental vessels under fetoscopy were successful. The described technique seems highly promising. Further experience will demonstrate whether it is without danger and simple enough to be used routinely in the prenatal diagnosis of congenital anomalies.

Anesthesia, Local↗
PubMed1996

-Interruption of umbilical blood flow in an acardiac twin by endoscopic laser coagulation-.

We report on the successful intrauterine surgical treatment of a twin pregnancy with an acardiac fetus. At 18 weeks of gestation the patient presented with polyhydramnios and a hydropic acardius acephalus and the donor twin showed signs of congestive heart failure. Colour Doppler ultrasound allowed localisation of the communicating vessels running on the placental surface towards the umbilicus of the acardiac twin. At 20 weeks we performed endoscopic laser coagulation of the umbilical vessels of the acardiac twin. A sheath (9.8 Charriere) with a 1.9 mm diameter rigid fetoscope (field of vision 60 degrees) was introduced percutaneously under local anesthesia into the amniotic cavity of the "pump" twin. Under sonographic control the fetoscope was directed towards the communicating vessels on the placental surface. A Nd-YAG laser (0.4 mm diameter fiber) was used to coagulate two vessels, artery and vein, until interruption of the reversed arterial perfusion was accomplished. Tricuspid regurgitation of the normal twin disappeared throughout the following two weeks and no further complications occurred throughout pregnancy. At 39 weeks a healthy girl was delivered vaginally. No at the age of 3 months she is developing normally. Minimal invasive endoscopic laser coagulation of the umbilical vessels of the acardiac twin appears to be the optimal currently available treatment for the normal twin, for which otherwise a high mortality ( > 50%) and morbidity must be expected.

Endoscopes↗
PubMed2001

Twin-twin transfusion syndrome: etiology, severity and rational management.

The twin-twin transfusion syndrome is a serious complication of monochorionic twin pregnancies. Partly as a result of an inadequate understanding of the pathophysiology of the syndrome, there is a lack of consensus in clinical management. We sought to review the available information on the etiology of twin-twin transfusion syndrome, to identify parameters that contribute to the severity of the syndrome, and propose a rational management plan based on pathophysiology, clinical presentation and the efficacy of therapies. We therefore amalgamated recent advances in twin-twin transfusion syndrome computer modelling and clinical studies, particularly on therapeutic outcomes. We found that the oligo-polyhydramnios sequence that defines twin-twin transfusion syndrome prenatally represents a wide continuum of severity in the imbalance between the fetoplacental circulations of both twins. In severe twin-twin transfusion syndrome cases, in which the circulatory imbalance deteriorates beyond fetal control, fetoscopic laser therapy of all anastomoses along the placental vascular equator is predicted to have significantly better survival rates and fewer neurological sequelae than amnioreduction. In contrast, mild twin-twin transfusion syndrome cases have better outcomes after one or at most a few amnioreductions than laser therapy, as a result of significantly fewer procedure-related risks. In conclusion, optimal individual therapy may possibly achieve an 85% survival rate in twin-twin transfusion syndrome, but requires advancement in non-invasive criteria that predict the severity of the syndrome. Identifying such criteria is a future challenge. For the interim, twin-twin transfusion syndrome diagnosed before 26 weeks' gestation has significantly better survival rates and fewer neurological sequelae after laser therapy than amnioreduction. Twin-twin transfusion syndrome diagnosed after 26 weeks can best be treated by amnioreduction, or delivery. Contrary to previous claims, fetoscopic laser therapy has outgrown its experimental status. Although improvements in technique and technology are likely, laser placental ablation has a firm scientific and clinical basis.

Amniotic Fluid↗
PubMed2003

Monochorionic diamniotic twins: complications and management options.

PURPOSE OF REVIEW: Monochorionic compared with dichorionic twins have disproportionately high fetal loss rates, perinatal mortality and morbidity. This is because of the unpredictable vascular anastomoses and the often asymmetrical distribution of the single placenta between both twins. RECENT FINDINGS: The pathophysiology of twin-to-twin transfusion syndrome is usually explained on an angioarchitectural basis, although certain hemodynamic and hormonal factors also may be involved. The results of the large randomized trials on amnioreduction, fetoscopic laser coagulation and septostomy are still awaited. An update is given on hardware and instruments required for fetoscopic laser. Subsequently, the problem of the monochorionic twin set with severe early discordant growth is addressed. Several etiological mechanisms have been proposed, but little is known of its natural history. Also, umbilical artery Doppler waveforms may not have the same predictive value as in singletons. Prophylactic laser coagulation of the vascular anastomoses to protect against the adverse effects of single intrauterine demise, has so far not been shown to confer any benefit in outcome. Finally, pathophysiology and management of discordant structural and chromosomal anomalies in monochorionic twins are discussed. Laser and monopolar coagulation, which can be introduced through a needle, may be used for selective feticide in early pregnancy or low hemodynamic conditions. Bipolar coagulation seems more effective at later gestational ages and normal hemodynamic conditions. SUMMARY: Our insight into the complications associated with monochorionic twins has increased in recent years. It is hoped that this will lead to better surveillance and ultimately an improved outcome for these high-risk pregnancies.

Amnion↗
PubMed1985

Fetoscopy in the assessment of unexplained fetal hydrops.

Pure fetal blood samples, obtained fetoscopically from 30 patients with unexplained fetal hydrops at 16 to 32 weeks gestation were investigated for cytogenetic, haematological, biochemical and virological properties. In two patients with oligohydramnios, the fetoscope was introduced transabdominally into the fetal peritoneal cavity and sampling was undertaken from the intra-abdominal portion of the umbilical vein; in all the other patients an umbilical cord vessel was sampled. Ten (33%) of the fetuses had chromosomal abnormalities, one an erythroblastic process, possibly erythroleukaemia, one alpha-thalassaemia and one cytomegalovirus infection. Blood-film abnormalities were seen in 23 (88%) of 26 fetuses that had this examination. Biochemical analysis of fetal plasma was undertaken in 18 fetuses and hypoproteinaemia was found in all cases. One fetus was subsequently found to have a paroxysmal tachyarrhythmia that responded to digitilization. Three (10%) of the fetuses survived.

Adolescent↗
PubMed1986

Effect of gestational age on fetal and intervillous blood gas and acid-base values in human pregnancy.

Intervillous, umbilical venous and umbilical arterial blood samples were obtained by cordocentesis or fetoscopically from 200 pregnancies at 16-38 weeks gestation. The fetuses were either not affected by the condition under investigation or it was one which would not affect blood gas and acid-base status. Blood pH, pO2, pCO2, bicarbonate, base excess and plasma lactate concentration were determined and ranges for each parameter are presented. Samples obtained fetoscopically were more acidotic, hypercapnic and had a greater base deficit than those obtained by cordocentesis. In the umbilical venous samples, the pO2 decreased, while the bicarbonate, base excess and lactate increased with gestation. In the umbilical arterial samples the pO2 decreased and pCO2 increased; there were no other significant changes with gestation. Similarly, in the intervillous samples the only significant change with gestation was that of a decrease in pO2.

Acid-Base Equilibrium↗
PubMed2001

Multimodal fetal transesophageal echocardiography for fetal cardiac intervention in sheep.

BACKGROUND: The overall performance of available mechanical intravascular ultrasound catheters for fetal transesophageal echocardiography during fetoscopic fetal cardiac interventions in sheep has been limited by radioelectronic interference, low system frame rates, and low acoustic outputs. Therefore, a more reliable device is desired for human fetoscopic surgical procedures. METHODS AND RESULTS: We assessed the potential of a newly available 10-French phased-array intravascular ultrasound catheter for multimodal fetal transesophageal echocardiography in 5 fetal sheep between 78 and 98 days of gestation (term, 145 to 150 d). The intravascular ultrasound catheter was easily inserted through the mouth into the esophagus in all 5 sheep fetuses (mean weight, 600 g), and it permitted high-quality 2D imaging of the fetal heart in vertical imaging planes that were validated by MRI. Color Doppler and pulsed Doppler imaging permitted clear assessment of fetal cardiovascular flows and recording of velocity-time integral tracings of the fetal heart and great vessels. The vertical imaging planes were particularly useful to demonstrate interventional material inside the fetal heart and great vessels. CONCLUSIONS: Our early experience with the phased-array intravascular ultrasound catheter indicates that multimodal fetal transesophageal echocardiography has now become possible in these smallest of patients.

Animals↗
PubMed1999

Cord occlusion techniques for selective termination in monochorionic twins.

We wished to determine the optimal method for cord obliteration to perform selective reduction in complicated monochorionic (MC) twin pregnancies under different clinical conditions. For this purpose, we reviewed our experience and the available published literature and unpublished reports. Indications were a cardiac twin pregnancy, twins discordant for fetal anomaly, and severe feto-fetal transfusion syndrome where one twin had a very poor prognosis. Data were available for the following techniques: cord embolization, fetoscopic cord ligation, laser coagulation, monopolar coagulation and bipolar cautery. Unfortunately the data are heterogeneous, incomplete and reports are only sporadic. Cord embolization using coils or sclerosants has a high failure rate and can no longer be recommended. In 23 published cases of fetoscopic cord ligation a failure rate of 10% was reported. After successful ligation an overall fetal survival rate of 71% but a risk of preterm prelabor rupture of the membranes (PPROM) of 30% was documented. Four cases of monopolar coagulation have been published--all in a cardiac twin pregnancies. In three cases the abdominal aorta was coagulated prior to 20 weeks and complete cessation of flow was demonstrated. In 10 cases of bipolar cord coagulation, all procedures were technically successful. Nine of 10 were performed under ultrasound guidance through a single port. In 2 cases, frank PPROM occurred, leading to induction of labor. The other eight fetuses were born at 35 weeks or more. Nd:YAG coagulation of the cord was much more sporadically described; the success of the procedure seems to be clearly dependant on gestational age. In all our attempts prior to 20 weeks, we failed in only one out of 6 cases. In summary, there is little data to perform meaningful comparisons of available techniques for umbilical cord occlusion. Based on practical and technical considerations we use the following clinical algorithm: prior to 21 weeks, we attempt to coagulate the cord with Nd:YAG laser. If this is unsuccessful, or for gestations beyond 21 weeks, bipolar cord coagulation is currently our other method of choice. Sonoendoscopic cord ligation is reserved as backup procedure if neither of these methods are successful.

Congenital Abnormalities↗
PubMed2002

Towards an endoscopic intra-uterine treatment for congenital diaphragmatic hernia.

Congenital Diaphragmatic Hernia (CDH) is a simple defect in the diaphragm that however can lead to severe or lethal pulmonary hypoplasia. Fetuses with their liver herniating into the thorax and with a small lung volume as reflected by a lung-to-head ratio below < 1.0, have virtually no chance to survive despite most modern postnatal care. They are therefore theoretical candidates for in utero therapy. There is a large experimental basis supporting tracheal occlusion (TO) as a method to trigger lung growth, although the optimal time and duration of TO remains to be defined in humans. Animal studies have also shown that TO can be performed completely endoscopically, by means of in utero tracheoscopy and endoluminal balloon placement. TO was therefore applied by leading fetal surgery centers. Initial results with tracheal clipping via hysterotomy were discouraging, but more recently fetoscopic clipping was associated with a nearly 70% survival. The time has now come to achieve TO by means of percutaneous fetoscopic balloon plugging. This will make the intervention more acceptable in a European setting, where open fetal surgery never took off.

Animals↗
PubMed1977

Sampling the fetoplacental circulation. II. Combined laparoscopy-fetoscopy in the pregnant ovine.

Induction of pneumoperitoneum, laparoscopy, and intrauterine endoscopy (fetoscopy) were successfully accompished in 23 pregnant sheep at 45 to 60 days' gestational age. The fetoscope, a conventional 2.7 mm. Hopkins straightforward wide-angle telescope (Stortz 27018A) encased in a prototype 3.1 mm. eccentric cannula, incorporates a 25 gauge needle channel. Multiple pregnancy was encountered in 11 animals. Forty-two separate fetoscopic trials were accomplished; a fetoplacental blood sample was obtained in 52 per cent of the trials. A mean interval of 19 +/- 9 days (+/- S.D., range 6 to 37 days) was allowed between fetoscopy trials. Fetal deaths occurred in nine animals (39 per cent). We believe that laparoscopy permits preselection of the proposed fetoscopy puncture site and will permit the operator to thereby avoid the placenta and/or uterine vessels.

Animals↗