Laser Ablation Of Placental Vessels Research Articles

Predictors of fetal death, neonatal survival and neurological outcomes in severe twin-twin transfusion syndrome treated by laser ablation of placental vessels.

To identify predictors of outcomes in severe twin oligo-polyhydramnios sequence (TOPS) with or without twin anemia-polycythemia sequence (TAPS) and/or selective fetal growth restriction (SFGR) treated by laser ablation of placental vessels (LAPV). Analysis of cases treated from 2011 to 2022. Variables evaluated Prenatal predictors: stages of TOPS, presence of TAPS and/or SFGR; pre-LAPV fetal ultrasound parameters; peri-LAPV variables. Perinatal predictors: GA at birth; birthweight; Apgar scores; transfontanellar ultrasonography (TFUS). fetal death, neonatal survival, infant's neurodevelopment. Binary logistic regression analyses were performed to detect predictors of outcomes. 265 cases were included. Predictors of post-LAPV donor fetus' death were delta EFW (p:0.045) and absent/reverse end-diastolic flow in the umbilical artery (AREDF-UA) (p<0.001). The predictor of post-LAPV recipient fetus' death was hydrops (p:0.009). Predictors of neonatal survival were GA at birth and Apgar scores. Predictors of infant's neurodevelopment were TFUS and pre-LAPV middle cerebral artery Doppler (MCAD) for the donor twin; and pre-LAPV ductus venosus' flow and MCAD for the recipient twin. Prediction of fetal death, neonatal survival and infant's neurodevelopment is possible in cases of TOPS associated or not with SFGR and/or TAPS that were treated by LAPV.

Type II and III Selective Fetal Growth Restriction: Perinatal Outcomes of Expectant Management and Laser Ablation of Placental Vessels

OBJECTIVES:To describe the perinatal outcomes of type II and III selective fetal growth restriction (sFGR) in monochorionic-diamniotic (MCDA) twin pregnancies treated with expectant management or laser ablation of placental vessels (LAPV).METHODS:Retrospective analysis of cases of sFGR that received expectant management (type II, n=6; type III, n=22) or LAPV (type II, n=30; type III, n=9). The main outcomes were gestational age at delivery and survival rate.RESULTS:The smaller fetus presented an absent/reversed “a” wave in the ductus venosus (arAWDV) in all LAPV cases, while none of the expectant management cases presented arAWDV. The median gestational age at delivery was within the 32nd week for expectant management (type II and III) and for type II LAPV, and the 30th week for type III LAPV. The rate of at least one twin alive at hospital discharge was 83.3% and 90.9% for expectant management type II and III, respectively, and 90% and 77.8% for LAPV type II and III, respectively.CONCLUSION:LAPV in type II and III sFGR twins with arAWDV in the smaller fetus seems to yield outcomes similar to those of less severe cases that received expectant management.

Endoscopic Laser Dichorionization of the Placenta in the Treatment of Severe Twin-Twin Transfusion Syndrome

Objectives: To describe the results of a technique of laser ablation of placental vessels in the treatment of severe twin-twin transfusion syndrome (TTTS), which is characterized by separation of the fetoplacental vascular territories and dichorionization of the placenta. Patients and Methods: Descriptive analysis of TTTS cases treated with the endoscopic laser dichorionization of the placenta (ELDP) procedure. The variables evaluated were the occurrence of reversal of the donor-recipient phenotype, persistence of TTTS or twin anemia-polycythemia sequence (TAPS); gestational age at delivery; discharge from the hospital of at least 1 or 2 live neonates, and incidence of neurological alterations among survivors. Results: 67 patients were treated with the ELDP procedure. There was no persistence of TTTS, reversal of the donor-recipient phenotype or TAPS. The median gestational age at delivery was 33.0 (23.6-37.7) weeks. The rate of discharge from the hospital of at least 1 or 2 live neonates was 88.2% (67/76) and 71.1% (54/76), respectively. Among survivors, 17 (17/121 = 14.0%) children presented with neurodevelopmental alterations during clinical follow-up. Conclusions: The major contribution of this study was the demonstration that the ELDP technique appears to be associated with a low risk of persistence or recurrence of TTTS and TAPS.

Laser Ablation of Placental Vessels in Twin-to-Twin Transfusion Syndrome: A Paradigm for Endoscopic Fetal Surgery

Endoscopic fetal surgery is most commonly used for the treatment of twin-to-twin transfusion syndrome (TTTS), but the surgical techniques can be applied to other forms of fetal surgery. We present our experience with endoscopic fetal surgery over the past 10 years. From 2000 to 2010, 70 endoscopic laser ablations of placental vessels for TTTS were performed. Median number of placental vessels ablated was four. The incidence of preterm rupture of membranes (PROM) was 6%. Overall survival was 70%, with at least one twin surviving in 82%. Tocolysis was used in 73% of patients for a median of 12 hours. The combination of an open surgical approach, Seldinger technique, and uterine plugging led to outcomes similar to other reports, with a significantly lower PROM rate. Although TTTS is the most common application of endoscopic fetal surgery, this approach is applicable for other indications. Insertion and removal of tracheal occlusion balloons for severe congenital diaphragmatic hernia are currently being performed at our institution.

Preoperative predictors of death in twin-to-twin transfusion syndrome treated with laser ablation of placental anastomoses

To determine preoperative predictive factors for donor and recipient death after laser ablation of placental vessels in twin-to-twin transfusion syndrome. Retrospective analysis of North American Fetal Therapy Network center laser procedures, 2002-2009. Factors associated with donor and recipient death were identified by regression analysis. There were 466 patients from 8 centers. Factors significantly associated with donor fetal death were low donor estimated fetal weight (odds ratio [OR], 0.69; 95% confidence interval [CI], 0.55-0.87) and reversed end diastolic velocity in the umbilical artery (OR, 4.0; 95% CI, 1.54-10.2); for recipient fetal death-low recipient estimated fetal weight (OR, 0.65; 95% CI, 0.44-0.95), recipient reversed "a" wave in the ductus venosus (OR, 2.39; 95% CI, 1.27-4.51) and hydrops (OR, 3.7; 95% CI, 1.1-12.7); for recipient neonatal death-low donor estimated fetal weight (OR, 0.54; 95% CI, 0.30-0.95), high recipient estimated fetal weight (OR, 1.55; 95% CI, 1.06-2.26) and recipient reversed end diastolic velocity in the umbilical artery (OR, 7.8; 95% CI, 1.03-59.3). Preoperative findings predict fetal and neonatal demise in twin-to-twin transfusion syndrome treated with laser therapy.

Maternal complications following endoscopic surgeries in fetal Medicine

To describe the maternal complications due to therapeutic endoscopic procedures in fetal Medicine performed at an university center in Brazil. Retrospective observational study including patients treated from April 2007 to May 2010 who underwent laser ablation of placental vessels (LAPV) for severe twin-twin transfusion syndrome (TTTS); fetal tracheal occlusion (FETO) and endoscopic removal of tracheal balloon in cases of severe congenital diaphragmatic hernia (CDH); LAPV with or without bipolar coagulation of the umbilical cord in cases of twin reversed arterial perfusion (TRAP) sequence. The main variables described for each disease/type of surgery were maternal complications and neonatal survival (discharge from nursery). Fifty-six patients underwent 70 procedures: Severe TTTS (34 patients; 34 surgeries); severe CDH (16 patients; 30 surgeries), and TRAP sequence (6 patients; 6 surgeries). Among 34 women who underwent LAPV for TTTS, two (2/34=5.9%) experienced amniotic fluid leakage to the peritoneal cavity and seven (7/34=20.6%) miscarried after the procedure. Survival of at least one twin was 64.7% (22/34). Among 30 interventions performed in cases of CDH, there was amniotic fluid leakage into the maternal peritoneal cavity in one patient (1/30=3.3%) and premature preterm rupture of membranes after three (3/30=30%) fetoscopies for removal of the tracheal balloon. Infant survival with discharge from nursery was 43.8% (7/16). Among six cases of TRAP sequence, there was bleeding into the peritoneal cavity after surgery in one patient (1/6=16.7%) and neonatal survival with discharge from nursery was 50% (3/6). In agreement with the available data in literature, at our center, the benefits related to therapeutic endoscopic interventions for TTTS, CDH and TRAP sequence seem to overcome the risks of maternal complications, which were rarely considered severe.

Ablação dos vasos placentários com laser para tratamento da síndrome de transfusão feto-fetal grave: experiência de um centro universitário no Brasil Laser ablation of placental vessels for treatment of severe twin-twin transfusion syndrome: experience from an university center in Brazil

To describe the results of laser ablation of placental vessels for the treatment of severe twin-to-twin transfusion syndrome in an university center in Brazil. Retrospective observational study of patients treated at UNICAMP from 2007 to 2009. Laser ablation of placental vessels was performed in cases of severe twin-twin transfusion syndrome (Quintero stages II, III and IV) diagnosed before 26 complete weeks of gestation. The main variables evaluated in this series were gestational age at delivery, survival (discharge from the nursery) of at least one twin and neurological damage in survivors. Logistic regression was used to investigate the influence of cervical length, gestational age and stage of the disease (before the surgery) on the occurrence of delivery/abortion and fetal death after the intervention, and the influence on severe preterm birth and survival. In the whole series, at least one twin survived in 63.3% of cases (19/30). Among patients who did not have delivery/abortion after surgery, the survival of at least one twin was 82.6% (19/23). In this subgroup (n=23), mean gestational age in delivery was 31.9 weeks and neurological damage was identified in one neonate (1/31; 3.2%). Cervix length influenced the occurrence of delivery/abortion after surgery (p-value=0.008). Among seven patients (7/30; 23.3%) who carried this complication, five (5/7; 71.4%) had cervix length lower than 15 mm. Among the 23 patients who did not have delivery/abortion as a result of the surgery, the highest stages of the disease (III and IV) increased the risk of delivery prior to 32 complete weeks of gestation (p-value=0.025) and decreased the chance of survival of both twins (p-value=0.026). The results are similar to those available in the literature. In our series, the main factors associated with poorer results were short cervix (lower than 15 mm) and the highest stages of the disease (III and IV) at the time of the treatment.

Feto–Fetal Transfusion Syndrome in Monochorionic Quadruplets

Endoscopic laser ablation of placental vessels is now the preferred treatment for severe feto-fetal transfusion syndrome in twin gestations, and has been well-documented in triplet gestations as well. Stage IV feto-fetal transfusion syndrome was diagnosed at 20.3 weeks of gestation between two of a set of monochorionic, tetramniotic quadruplets. Endoscopic laser ablation occurred at 20.4 weeks. Feto-fetal transfusion recurred at 22 weeks between the initial donor and the two previously unaffected fetuses. Delivery occurred at 24.9 weeks. The donor and one of the corecipients died shortly after birth. The sole survivor was doing well. Treatment of feto-fetal transfusion syndrome in higher-order gestations is challenging because of the increased pregnancy risks, the difficult angioarchitecture and the risk of recurrence.

Current Status of Minimal Access Surgery (MAS) in the Field of Maternal-Fetal Medicine

Advances in medical imaging have led to an improvement in prenatal diagnosis of congenital anomalies. This has been made possible through the incorporation of new ultrasound technologies, use of doppler and real time imaging. These have resulted in improvement in resolution and quality of ultrasound images. Concurrent use l Magnetic Resonance Imaging (MRI) in fetal imaging has resulted in better definition of pathology and diagnosis in situation where ultrasound imaging turns to be inconclusive.1 Together with the accolades gained by medical science in the understanding of the pathophysiological basis of diseases, clinicians have never been better equipped in making accurate diagnosis and better positioned in counselling their patients regarding prognosis and options available for the fetal condition in question, as is the case now. Sir William Albert Liley is regarded as the ‘father of fetal medicine’. His successful intrauterine transfusion of fetus affected by Rhesus disease in New Zealand, in 1963, opened a multitude of possibilities and opportunities for fetal medicine specialists.2,3 This has been followed by different developments, animal studies and refining of skills. The Fetal treatment center at the University of California, San Francisco (UCSF), under the leadership of Michael Harrison (a pediatric surgeon by training), has been at the forefront of this development.4 This center has been in limelight for performing fetal open fetal surgery and later inversion of minimal fetal approach dubbed ‘FETENDO’ (use of small instruments and manipulating them inside the uterine cavity was viewed as similar to playing video games, hence the name). Other groups like the children’s hospital of Philadelphia (CHOP), and the fetal center at Leuven, etc joined suite.2 There are now few specialized centers in different countries dedicated to this cause. The end result has been research and refinement of skills as new knowledge is acquired.4-6 The observation that postnatal therapy was not the answer to all fetuses, has led to the emergence of fetal surgery over the last 30 years. The vision has been an attempt to salvage the few fetuses with conditions that are known to result in stillbirth if left untreated, arrest the pathophysiological process or reverse fetal damage that is not amenable to postnatal correction. Currently three approaches are available for intrauterine management of fetal conditions, open approach via hysterotomy or minimal access using endoscopy or Fetal Image Guided Surgery (FIGS).6 The latter approach is what is generally referred to as percutaneous approach. This procedure uses needles to access the fetus under ultrasound guidance. Fetal surgery has undergone evolution from the first successful intrauterine transfusion in New Zealand, hysterotomy for vascular access and intrauterine transfusion (Puerto Rico, 1964), diagnostic fetoscopy (Yale, 1974), Laser ablation of placental vessels (Milwaukee, London,1995) right to the use of amniotic collagen plug (Leuven, 2007) and sclerotherapy for congenital cystic adenomatous malformation (CCAM) performed in Venezuela in 2007. A comprehensive review of these milestones is well articulated in the article by Jancelewicz and Harrison.2 Abstract

Reflectance spectrometry for real-time hemoglobin determination of placental vessels during endoscopic laser surgery for twin-to-twin transfusion syndrome

Objective The objective of the study was to develop a noninvasive technique to determine hemoglobin (Hb) content through spectral analysis of diffusely reflected broadband visible illumination from individual blood vessels during endoscopic fetal surgery for twin-to-twin transfusion syndrome (TTTS). Methods The reflection of an incoming xenon endoscopic light source was captured through a 630- μm–diameter optic fiber coupled to a fixed grating spectrometer (2-nm resolution). A 450- to 700-nm wavelength range was used for analysis. Three data-capturing methods were studied: (1) fixed-image spectrum capture with fiber aimed at (but not touching) center of a vessel, (2) no-touch scanning perpendicular to the vessel and dynamic spectral capture, and (3) dynamic spectral capture and analysis of the reflectance spectra during brief vessel touch. Results Eight controls (elective laparoscopic and thoracoscopic operations in children aged 1-17 years) were enrolled. Four vessels were analyzed in each case. The brief-touch technique with intensity peak analysis yielded the most reproducible results between multiple vessels in the same patient. Spectrometry was also applied to 2 TTTS patients. The (anemic) donor and (polycythemic) recipient twin fetuses could be differentiated with good correlation between vessels (arteries and vein) of the same fetus. Conclusions It is possible to differentiate donor from recipient placental vessels by spectral analysis of the reflected light through the endoscope using a noninvasive and real-time method. This may improve the accuracy of endoscopic laser ablation of placental vessels in TTTS and may allow instant endoscopic Hb determination for laparoscopic procedures as well.

The Pediatric Surgeons’ Contribution to In Utero Treatment of Twin-to-Twin Transfusion Syndrome

To evaluate the outcome of twin-to-twin transfusion syndrome (TTTS) treated using a combination of endoscopic fetal surgery-specific techniques and surgical restraint. TTTS is a condition of identical twins that, if progressive and left untreated, leads to 100% mortality. The best treatment option is obliteration of the intertwin placental anastomoses, but fetal surgery carries significant maternal and fetal risks. Even if successful, percutaneous endoscopic laser ablation of placental vessels (LASER) causes premature rupture of membranes (PROM) in 10% to 20% of pregnancies. Patient selection is particularly critical because the progression of the disease is unpredictable. This has prompted many to intervene early, yielding survival rates of >=1 twin of 75% to 80%. We developed a minimally invasive approach to fetal surgery, a unique membrane sealing technique and a conservative algorithm that reserves intervention for severe TTTS. Pregnancies with TTTS (stages I-IV) managed in the last 8 years were reviewed. LASER was offered in stage III/IV only. Ninety-eight cases of TTTS were managed in a pediatric surgery/maternal-fetal medicine collaborative Fetal Treatment Program-39 were observed (40%) and 59 underwent LASER (60%). Survival of >= twin was seen in 82.7%, and overall survival was 69.4%. These survival rates are similar to, or better than, other comparable series with similar stage distribution (low:high stage ratio 1:1) in which all patients underwent LASER. PROM rate was 4%. Reserving LASER treatment for severe TTTS results in outcomes similar to, or better than, LASER for all stages. Applying fetal surgery-specific endoscopic techniques, including port-site sealing, reduces postoperative complications.

Survival after laser surgery for twin-to-twin transfusion syndrome: when are they out of the woods?

Purpose Severe, progressive twin-to-twin transfusion syndrome (TTTS) is associated with near-100% mortality if left untreated. Endoscopic laser ablation of placental vessels (ELA) is associated with 75% to 80% survival of at least one twin. The actuarial risk of fetal demise after ELA has not yet been described. Study Design A retrospective cohort study from 2 centers on a consecutive series of 163 sets of monochorionic twins with severe TTTS (18 Quintero stage I, 55 stage II, 71 stage III, 19 stage IV) who underwent ELA. Actuarial survival was calculated and stratified for donor vs recipient and according to stage. Results Median gestational age at diagnosis was 20.1 weeks; median operative time was 60 minutes. Overall survival was 63%, and survival of at least one twin was seen in 76% of pregnancies. Of fetal demises, 10% occurred within 48 hours after ELA, and 90% of all fetal demises occurred within 1 month. There was a 10% survival advantage of recipients over donors. Survival was similar for stages I, II, and IV (75%-80%), compared with 55% for stage III. Conclusions Actuarial survival curves for TTTS confirms a greater burden on donor than on recipient but not at a previously reported 2:1 ratio. The current staging system does not accurately reflect post-ELA mortality risk. The unexpected higher mortality in stage III may reflect a more acute progression of the disorder in this group, an adverse effect of LA on an as yet unknown subgroup with stage III or, alternatively, preoperative demise of fulminant stage IV patients, leaving a stage IV subgroup with a more benign course and better outcome.

Fetoscopic laser ablation of placental vessels in severe previable twin-twin transfusion syndrome: De Lia J.E.; Kuhlmann R.S.; Harstad T.W.; Cruikshank D.P. Am J Obstet Gynecol 1995 172/4 I (1202–1211)

Fetoscopic laser ablation of placental vessels in severe previable twin-twin transfusion syndrome: De Lia J.E.; Kuhlmann R.S.; Harstad T.W.; Cruikshank D.P. Am J Obstet Gynecol 1995 172/4 I (1202–1211)

Fetoscopic laser ablation of placental vessels in severe previable twin-twin transfusion syndrome

OBJECTIVE: We undertook a pilot study to determine the feasibility and efficacy of fetoscopic laser occlusion of chorioangiopagous vessels in severe previable twin-twin transfusion syndrome. STUDY DESIGN: A total of 35 patients were referred to the investigators with ultrasonographic findings consistent with twin-twin transfusion syndrome, posterior placental implantation, gestational age < 25 weeks, and clinical hydramnios. Placental vessel occlusion was performed with a rigid 2.9 × 3.85 mm dual-channel fetoscope and neodymium:yttrium-aluminum-garnet laser light. RESULTS: Of the original 35 patients, 5 were eliminated preoperatively and 4 intraoperatively for various factors. The 26 treated patients had a mean gestational age of 20.8 weeks (range 18 to 24) and a mean fundal height of 36.1 cm (range 29 to 44). One patient has surviving triplets, 8 have surviving twins, 9 have a single survivor (2 neonatal and 7 fetal deaths occurred in this group), and 8 have no survivors (all had pregnancy loss within 3 weeks of treatment). The cases with survivors were delivered for obstetric indications at a mean of 32.2 weeks (range 26 to 37), having gained a mean of 11.7 weeks (range 6 to 17) in utero. Fifty-three percent ( 28 53 ) of the fetuses survived with 96% ( 27 28 ) developing normally at a mean age of 35.8 months (range 1 to 68). Thirty-three of 35 placentas were monochorionic with chorioangiopagous vessels on gross and microscopic evaluation. CONCLUSIONS: Fetoscopic laser occlusion of chorioangiopagous vessels is technically feasible and improves the course and outcome of severe twin-twin transfusion syndrome in previable fetuses.