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R A Quintero

Publications and source records attributed to R A Quintero.

At least 37 records · Page 2Linked to original sources
PubMed2000

Successful in utero endoscopic ablation of posterior urethral valves: a new dimension in fetal urology.

Fetal lower urinary tract obstructive uropathy, when associated with oligohydramnios, is usually associated with a poor outcome. We present a case of successful in utero endoscopic ablation of posterior urethral valves in which the infant survived the neonatal period without evidence of renal dysplasia. The role, indications, and potential benefits of this novel technique are discussed.

Cystoscopy↗
PubMed2000

Minimally invasive treatment of twin-to-twin transfusion syndrome.

Selective laser photocoagulation of communicating vessels (SLPCV) is an application of minimally invasive endoscopic fetal surgery (i.e., surgical fetoscopy) performed for severe cases of twin-to-twin transfusion syndrome (TTTS), a complication of monochorionic twin pregnancies. Advances in ultrasound and endoscopy have aided the identification and treatment of this potentially lethal or fatal condition. Surgical fetoscopy, an innovation in the field of surgery and maternal-fetal medicine, benefits patients by reducing the morbidity and mortality associated with TTTS, with minimal risks to the mother.

Amniocentesis↗
PubMed2000

Selective versus non-selective laser photocoagulation of placental vessels in twin-to-twin transfusion syndrome.

OBJECTIVE: We have recently described a surgical technique for the treatment of twin-to-twin transfusion syndrome (TTTS) that allows precise identification of vascular anastomoses (selective laser photocoagulation of communicating vessels, or S-LPCV). The purpose of this study was to compare S-LPCV with the previous non-selective technique (NS-LPCV) that targeted all vessels crossing the dividing membrane. MATERIALS AND METHODS: Patients with TTTS were treated with NS-LPCV from May 1994 to June 1997 and with S-LPCV from July 1997 to December 1999. TTTS was defined as polyhydramnios of > or = 8 cm maximum vertical pocket (MVP) in the recipient twin and oligohydramnios of < or = 2 cm MVP in the donor twin. Outcome was measured as survival per number of pregnancies and per number of fetuses together with limited morbidity data. RESULTS: NS-LPCV was used in 18 patients and 74 were treated with S-LPCV. Three patients interrupted their pregnancies electively after surgery (S-LPCV) and were removed from further analysis. Survival of at least one fetus was higher in S-LPCV (83.1%) than in NS-LPCV (61.1%) (P = 0.04), mostly due to a lower rate of dual intra-uterine fetal demise in S-LPCV (5.6%) than in NS-LPCV (22%) (P = 0.05). There were more hydropic fetuses in the NS-LPCV group (27%) than in the S-LPCV group (5.4%), but this difference did not account for the results. There was no difference in the survival per number of fetuses between the two groups. CONCLUSIONS: S-LPCV represents an important evolution in the surgical treatment of TTTS. The use of this technique by all centers should allow better comparison of fetal survival and morbidity rates. S-LPCV should be the standard technique in trials comparing amniocentesis versus laser for the treatment of severe TTTS.

Arteriovenous Anastomosis↗
PubMed2000

Fetal hydrolaparoscopy and endoscopic cystotomy in complicated cases of lower urinary tract obstruction.

OBJECTIVE: Vesicoamniotic shunting may be difficult or impossible in selected cases of fetal lower obstructive uropathy. The purpose of this article is to describe the performance of fetal hydrolaparoscopy and endoscopic fetal cystotomy in two fetuses with complicated lower obstructive uropathy. STUDY DESIGN: Fetal hydrolaparoscopy-endoscopic fetal cystotomy was performed in a patient with a markedly thickened bladder that could not be entered percutaneously. A peritoneoamniotic (bridge) shunt was also placed. Fetal hydrolaparoscopy-endoscopic fetal cystotomy was performed in a second patient with a collapsed bladder from a previous vesicocentesis, because vesicoinfusion resulted in further ascites. Fetal cystoscopy was performed after endoscopic fetal cystotomy, and posterior urethral valves were ablated with neodymium:yttrium-aluminum-garnet laser energy. A vesicoamniotic shunt was left in place. RESULTS: Adequate bladder drainage was obtained in both cases. The first baby required bilateral nephrotomy and a permanent cystotomy at birth and is scheduled for a bladder expansion procedure at the age of year. The second patient had premature rupture of membranes and fetal death from treatment of this complication 5 days after the original procedure. CONCLUSION: Fetal hydrolaparoscopy-endoscopic fetal cystotomy can be performed in complicated cases of lower obstructive uropathy. The procedure involves the creation of a defect in the bladder dome under direct endoscopic visualization within a spontaneous or intentional hydroperitoneum. Peritoneoamniotic shunting, vesicoamniotic shunting, or ablation of posterior urethral valves may then be performed. Fetal hydrolaparoscopy-endoscopic fetal cystotomy should be reserved only for complicated cases of lower obstructive uropathy in which conventional vesicoamniotic shunting is not safely possible. Further experience with fetal hydrolaparoscopy-endoscopic fetal cystotomy is necessary to establish its risks and benefits.

Adult↗
PubMed1999

In vitro laser welding of amniotic membranes.

OBJECTIVE: To test in vitro the feasibility of welding amniotic membranes using Nd:YAG laser energy. STUDY DESIGN: Fresh fetal membranes from term pregnancies were washed and cut into 1 cm2 pieces. Pooled cryoprecipitate (CPT), 50% albumin (Alb), or polytetrafluoroethilene (e-PTFE) were used as solder medium. The optimal settings of the laser were determined. Results were assessed quantitatively and semi-quantitatively using Pearson Chi-square analysis. RESULTS: Laser welding of amniotic membranes was successful in 82.6% of experiments with e-PTFE and in 10.7% of experiments with CPT (P < 0.001). The strength of the welding was also significantly better with e-PTFE (P < 0.001). Optimal results were obtained using 1-7 Watts and 0.1-1 seconds. Laser welding was unsuccessful in 100% of experiments with Alb. CONCLUSIONS: Laser welding of fetal membranes can be accomplished with e-PTFE and to a lesser degree with the CPT using Nd:YAG energy under low wattage-high exposure settings. Further studies are underway to test other grafting or soldering materials.

Extraembryonic Membranes↗
PubMed1999

Treatment of iatrogenic previable premature rupture of membranes with intra-amniotic injection of platelets and cryoprecipitate (amniopatch): preliminary experience.

OBJECTIVE: Our aim was to describe the treatment of iatrogenic previable premature rupture of membranes with the intra-amniotic injection of platelets and cryoprecipitate (amniopatch). STUDY DESIGN: Patients with iatrogenic previable premature rupture of membranes and without evidence of intra-amniotic infection underwent transabdominal intra-amniotic injection of platelets and cryoprecipitate through a 22-gauge needle. The study was approved by the Institutional Review Board of St Joseph's Hospital in Tampa, Florida, and all patients gave written informed consent. RESULTS: Seven patients with iatrogenic preterm premature rupture of membranes underwent placement of an amniopatch. Membrane sealing was verifiable in 6 of 7 patients. Three patients had iatrogenic preterm premature rupture of membranes after operative fetoscopy, 3 cases were after genetic amniocentesis, and 1 was after diagnostic fetoscopy. Three pregnancies progressed well, with restoration of the amniotic fluid volume and no further leakage. Two patients had unexplained fetal death despite successful sealing. One case of bladder outlet obstruction had no further leakage, but oligohydramnios persisted and did not allow unequivocal documentation of sealing. One patient miscarried from twin-twin transfusion, but the amniotic cavity was sealed. CONCLUSIONS: Iatrogenic preterm premature rupture of membranes can be treated effectively with an amniopatch. The technique is simple and does not require knowledge of the exact location of the defect. Unexpected fetal death from the procedure may be attributable to vasoactive effects of platelets or indigo carmine. Although the appropriate dose of platelets and cryoprecipitate needs to be established, the amniopatch may mean that iatrogenic preterm premature rupture of membranes no longer needs to be considered a devastating complication of pregnancy.

Adult↗
PubMed1999

Staging of twin-twin transfusion syndrome.

OBJECTIVE: The purpose of this study was to evaluate the prognostic value of sonographic and clinical parameters to develop a staging classification of twin-twin transfusion syndrome (TTTS). STUDY DESIGN: Severe TTTS was defined as the presence of polyhydramnios (maximum vertical pocket of > or = 8 cm) and oligohydramnios (maximum vertical pocket of < or = 2 cm). Nonvisualization of the bladder in the donor twin (-BDT) and absence of presence of hydrops was also noted. The middle cerebral artery, umbilical artery, ductus venosus, and umbilical vein in both fetuses were assessed with pulsed Doppler. Critically abnormal Doppler studies (CADs) were defined as absent/reverse end-diastolic velocity in the umbilical artery, reverse flow in the ductus venosus, or pulsatile flow in the umbilical vein. TTTS was staged as follows: stage I, BDT still visible; stage II, BDT no longer visible, no CADs; stage III, CADs; stage IV, hydrops; stage V, demise of one or both twins. Laser photocoagulation of communicating vessels (LPCV) or umbilical cord ligation was performed depending on the severity of the condition. The study was approved by the Institutional Review Board of St. Joseph's Hospital in Tampa and by the Fetal Therapy Board at Hutzel Hospital, Detroit, and all patients gave informed consent. RESULTS: A total of 80 of 108 referred patients met criteria for surgery, but only 65 were treated surgically: 48 with LPCV and 17 with umbilical cord ligation. Complete Doppler data were obtainable in 41 of 48 LPCV patients. Survival rates by stage for one or two fetuses were statistically different (chi-squared analysis = 12.9, df = 6, p = 0.044). Neither percent size discordance nor gestational age at diagnosis were predictive of outcome. CONCLUSION: Staging of TTTS using the proposed criteria has prognostic significance. This staging system may allow comparison of outcome data of TTTS with different treatment modalities.

Amniocentesis↗
PubMed1998

Transabdominal intra-amniotic endoscopic assessment of previable premature rupture of membranes.

OBJECTIVE: Our purpose was to describe the endoscopic characteristics of the site of rupture in vivo in patients with spontaneous premature rupture of membranes. STUDY DESIGN: Patients with preterm premature rupture of membranes between 16 and 26 weeks of gestation, without evidence of intra-amniotic infection, and with a normal karyotype underwent transabdominal endoscopic examination of the amniotic cavity. Subsequently, an amniopatch of a combination of platelets and cryoprecipitate to seal the membrane defect was administered. The study was approved by the Institutional Review Board of St. Joseph's Hospital in Tampa, Florida, and all patients gave written informed consent. RESULTS: Four patients underwent endoscopic examination and amniopatch administration; three had spontaneous preterm premature rupture of membranes, and in the other the membranes ruptured after an early amniocentesis. The location of the site of rupture was over the internal os in the 3 cases with spontaneous preterm premature rupture of membranes. This area was normal in the patient with iatrogenic preterm premature rupture of membranes. The longer the time between preterm premature rupture of membranes and fetoscopy, the larger and less defined was the site of rupture. The amniopatch restored amniotic integrity for a maximum of 72 hours. CONCLUSIONS: This is the first in vivo endoscopic visualization of the site of spontaneous rupture of membranes from within the uterine cavity. The defect is located over the internal cervical os in patients with spontaneous preterm premature rupture of membranes. There appear to be time-related changes in the morphologic characteristics of the site of rupture. Endoscopic visualization of the site of rupture has the potential for improving our understanding of spontaneous preterm premature rupture of membranes and in the development of possible therapeutic alternatives.

Abdomen↗
PubMed1997

In utero lysis of amniotic bands.

Amniotic band syndrome is a sporadic condition that occurs in approximately 1:1200 to 1:15,000 live births and that may result in amputations, constrictions and other deformities of the fetus. Although some cases present with congenital anomalies that are beyond surgical repair, a selected group of fetuses may show isolated limb constriction. It has been speculated that, without treatment, amputation or severe dysfunction of the limb may occur. Despite these potential complications, surgical treatment for this selected group of fetuses has not been previously performed. We report two cases that were successfully treated using novel minimally invasive surgical techniques. The cases involved fetuses with amniotic band syndrome with associated limb constriction in which the amniotic band was surgically interrupted to avoid spontaneous amputation of the extremity. Adequate blood flow distal to the obstruction was preserved and significant functional improvement of the extremity occurred in both cases, preserving the limbs. These cases represent the first prenatal surgical intervention successfully used to treat constricting amniotic bands in humans. In addition, these cases represent the first time that a non-lethal fetal entity has been surgically treated in utero. The results of this innovative therapy will encourage the efforts to continue developing minimally invasive techniques for the correction of birth defects.

Adult↗
PubMed1997

Congenital abnormalities in twins: selective termination.

Selective termination for an anomalous twin in discordant twin pregnancy has been a management option for nearly two decades. Using current conventional prenatal diagnostic techniques, the diagnosis of a twin gestation discordant for a congenital anomaly is commonly confirmed in the second trimester. Selective termination is thus usually a second-trimester procedure. The risks of second-trimester terminations as well as protocol choices, including indications and timing, have evolved over the years. Ethical issues regarding selective termination have developed significantly and continue to be debated.

Congenital Abnormalities↗
PubMed1996

In utero percutaneous umbilical cord ligation in the management of complicated monochorionic multiple gestations.

The study was designed to report our experience with in utero percutaneous umbilical cord ligation for selective feticide in pre-viable, abnormal, monochorionic multiple gestations. The selection criteria prior to offering percutaneous umbilical cord ligation included normal anatomy in the other fetus(es), normal karyotype and polyhydramnios, or uterine contractions. The procedure was performed under combined endoscopic and sonographic guidance. Fifteen patients were referred for evaluation and possible treatment. Two patients were excluded because of misdiagnosis. The mean gestational age at the time of the procedure was 21 weeks (range 16-25 weeks). There were ten acardiac twins, one discordant twin with acrania, and two cases of twin-twin transfusion syndrome with a hydropic twin. Percutaneous umbilical cord ligation was accomplished in 11/13 (84%) cases. An average of 8.5 weeks (range 0-18.5 weeks) was gained after percutaneous umbilical cord ligation, and five of 11 patients delivered at or after 30 weeks. Seven of 11 patients undergoing ligation procedures had living children. Premature rupture of membranes occurred within 3 weeks in 4/13 (30%) of cases. In utero fetal demise remote from the procedure occurred in three ligated patients undergoing ligation, in two of which intraoperative bleeding occurred. One fetus with cystic fibrosis died in the newborn period. Percutaneous umbilical cord ligation is an evolving alternative technique for the management of abnormal monochorionic multiple gestations. The advantages of percutaneous umbilical cord ligation over other approaches include complete extravascular interruption of the blood flow in all vessels of the cord. This may prevent postmortem feto-fetal hemorrhage or possible embolic phenomena that may result in death of the normal twin, as seen with intravascular techniques. Percutaneous umbilical cord ligation prior to spontaneous death of a co-twin may also avert the neurological and other complications that may occur in the surviving twin. Technological advances should decrease the observed complications and improve the success rate of the procedure.

Diseases in Twins↗
PubMed1996

In utero endoscopic devascularization of a large chorioangioma.

Clinically significant chorioangiomas, i.e. those greater than 4 cm in diameter, are associated with an overall fetal loss rate of approximately 40%. Maternal complications may also be present. Most patients diagnosed with chorioangiomas have been managed expectantly. A patient with a large chorioangioma was referred to our institution, with a fetus that was hydropic and showed sonographic signs of over heart failure. Fetal anemia, marked erythropoiesis and hypoalbuminemia were documented on cordocentesis. The blood supply to the mass consisted of an artery and a vein of 9 mm in diameter. The vascular supply to the tumor was ablated via operative fetoscopy by suture ligation of the arterial supply, after subchorionic dissection of the vessel. The remaining blood supply was electrocoagulated with bipolar cautery. Although the procedure was technically successful, the fetus died on the 3rd postoperative day. This case illustrates ablation of the blood supply of placental chorioangiomas as a potential management alternative for those patients with large chorioangiomas. Early identification and treatment may result in a successful outcome.

Endoscopy↗
PubMed1996

Ethical issues surrounding multifetal pregnancy reduction and selective termination.

MFPR and selective terminations satisfy the criteria of enabling pregnancies to continue with the least harm and most benefits to all involved. The surviving infants can be saved from certain death (abortion) or higher risks of severe harm and death and of an extended stay in neonatal intensive care (premature delivery). In the hands of trained operators, MFPR and selective termination is, in our opinion, the best means to protect the mother's health and well-being, given it is available and approved by the parents. MFPR and selective termination avoid the trauma of abortion of a wanted pregnancy, enable the parents to achieve the goal of having their own child, and avoid the dangers of delivery of multiple premature infants. There is no doubt that any procedure that involves the death of a fetus will be hotly argued despite the potential for greater good. We acknowledge that it will be impossible to convince those who cannot morally accept the taking of any life regardless of the circumstances. We hope, however, that we have shown there is a place for MFPR and selective termination in a very limited number of circumstances and the ethical probity of MFPR and selective termination as an option in such cases.

Congenital Abnormalities↗
PubMed1995

In-utero percutaneous cystoscopy in the management of fetal lower obstructive uropathy.

In fetuses with lower obstructive uropathy, sonography cannot establish the cause of obstruction. We assessed whether percutaneous fetal cystoscopy could be useful in the evaluation and treatment of obstructive defects in utero. We inserted a fibreoptic endoscope through the lumen of the needle or trocar into the fetal bladder at the time of vesicocentesis or vesicoamniotic-shunt placement and looked at the the urethra, bladder neck, and ureteral orifices. Urethral vesicoamniotic shunting was considered in suitable cases; otherwise a percutaneous shunt was inserted. Fetal cystoscopy was possible in 11 of 13 patients referred. The bladder mucosa appeared haemorrhagic or oedematous in three. The ureteral orifices were seen in 9/11 fetuses, dilation was seen in five, but was only suspected in two by ultrasound. Ureteral webs were noted in two other fetuses. Two of seven fetuses underwent urethral vesicoamniotic shunting; urethral patency was achieved with urethral probing alone in one fetus. The remaining four fetuses were shunted with a standard technique. Fetal cystoscopy helps define the underlying conditions responsible for sonographic findings of lower obstructive uropathy, and allows the introduction of new treatments.

Amniotic Fluid↗
PubMed1995

Percutaneous fetal cystoscopy and endoscopic fulguration of posterior urethral valves.

Percutaneous fetal cystoscopy was performed in a male fetus with ultrasonographic evidence of lower urinary tract obstruction at 19 weeks of gestation. The diagnosis of posterior urethral valves was confirmed. Percutaneous endoscopic fulguration of the valves was successfully performed at 22 weeks of gestation, and urethral patency was established. This case illustrates the feasibility of performing diagnostic and therapeutic endoscopic procedures within the human fetus for the management of a congenital anomaly. While we believe that fetal cystoscopy may improve our diagnostic, prognostic, and therapeutic capabilities in the management of fetuses with lower obstructive uropathy, studies are needed to establish the actual value, risks, and limitations of this new approach in fetal medicine.

Adult↗
PubMed1995

In utero sonographic diagnosis of vesicoureteral reflux by percutaneous vesicoinfusion.

Vesicoureteral reflux affects approximately 1% of newborns. Although most affected children show only sonographic evidence of renal pelvic dilatation, others may show overt hydronephrosis, indistinguishable from that seen in fetuses with obstructive uropathy. Hydronephrosis secondary to fetal vesicoureteral reflux cannot be differentiated on ultrasound examination from that resulting from lower obstructive uropathy with or without reflux. As renal damage from vesicoureteral reflux may occur in up to 70% of cases, early identification and possible in utero treatment of these fetuses may be warranted. We report a sonographic technique, vesicoinfusion, for diagnosis of vesicoureteric reflux in utero. The accurate identification of vesicoureteral reflux in utero may have important diagnostic, prognostic and therapeutic implications.

Abortion, Therapeutic↗