1/21. Cord ultrasonic transection procedure for selective termination of a monochorionic twin.Placental vascular communications can present a life-threatening problem in monochorionic twins when one fetus has a lethal anomaly. Although selective feticide is the best option for salvaging the normal twin, techniques normally employed (i.e. intracardiac potassium, air embolism) are not prudent given the common circulatory system. Furthermore, in monoamniotic, monochorionic twin gestations it is important to transect the umbilical cord completely to prevent entanglement of the dead fetus around the cord of the normal twin. We present two cases of monochorionic twins in which the cords were transected with a harmonic scalpel under ultrasonic guidance via one trocar. The harmonic scalpel is an instrument which can simultaneously coagulate and cut blood vessels or tissues. The cord ultrasonic transection procedure is a novel, minimally invasive technique which offers several advantages over the methods currently used for selective feticide in discordant monochorionic twin gestations.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
2/21. Ultrasound in the diagnosis of twin-to-twin transfusion syndrome--a preliminary report.OBJECTIVE: The aim of this study was to show the diagnostic possibilities of ultrasound in twin-to-twin transfusion syndrome (TTTS), to demonstrate its usefulness in cases of hemoglobin difference < 5 g/dL in neonates as well as in cases complicated by intrauterine death of one or both twins. STUDY DESIGN: The study included 4 pairs of twins. In two cases 3 fetuses died in utero. In the other two the hemoglobin difference in newborn infants was < 5 g/dL. The ultrasound examination, evaluating the fetal anatomy and biometry, amniotic fluid volume, placentation, was performed. The special attention was paid to polyhydramnios/oligohydramnios, discordant fetal growth (fetal weight, abdominal circumference), the presence of fetal hydrops, ascites, pericardial effusion. Doppler blood flow velocimetry has been done in umbilical vessels, middle cerebral artery. The data was compared with normal reference values for singleton pregnancies. The waveforms from both uterine arteries were also evaluated to exclude placental insufficiency. Additionally the blood flow through the AV valves was measured to exclude or confirm its regurgitation. Postnatally the hemoglobin difference was evaluated if available and compared with sonographic findings. RESULTS: In all cases inter-twin difference in abdominal circumference was greater than 18 mm and inter-twin weight difference of more than 15%. We observed polyhydramnios/oligohydramnios in all twin pregnancies. It has been found decreased PI in middle cerebral artery in larger fetus (recipient) in all our cases (comparing to single pregnancy). PI values for this vessel in smaller fetuses were within normal range (for single pregnancy). PI values in umbilical arteries of recipients were abnormal (increased PI or absent end-diastolic flow). COMMENTS: The sonographic criteria seem to be very useful in diagnosis of twin-to-twin transfusion syndrome, especially in cases where the measurement of hemoglobin level is impossible. Doppler blood flow velocimetry in fetal vessels helps to explain the changes in fetal hemodynamics in TTTS.- - - - - - - - - - ranking = 3keywords = vessel (Clic here for more details about this article) |
3/21. Severe polyhydramnios in twin reversed arterial perfusion sequence: successful management with intrafetal alcohol ablation of acardiac twin and amniodrainage.We present two cases of twin reversed arterial perfusion (TRAP) sequence complicated by severe polyhydramnios during the second trimester. Both cases were successfully managed at 27 and 26 weeks with ultrasound-guided intrafetal alcohol ablation of the acardiac twin and amniodrainage. The pump twins were delivered at 35 and 37 weeks, respectively, and both had uneventful postnatal courses. These cases suggest that, in the setting of severe polyhydramnios, prenatal intervention in TRAP sequence could certainly improve the otherwise poor prognosis of the pump twin. Targeting the main intra-abdominal vessel of the acardiac twin rather than its umbilical cord seems to be a good alternative in the prenatal treatment of these cases. The option of percutaneous intrafetal alcohol injection is widely available and less invasive, simpler and easier to perform than recently advocated endoscopic techniques.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
4/21. Intrauterine left chamber myocardial infarction of the heart and hydrops fetalis in the recipient fetus due to twin-to-twin transfusion syndrome.A rare complication of twin-to-twin transfusion syndrome (TTTS) is described: myocardial infarction of the recipient fetus. myocardial infarction and hydrops are considered to be consequences of hypertension in the recipient. No other organs were affected. Pathological signs of intrauterine hypertension were estimated by the thickness of vessel walls and signs of hypertrophied myocardial cells. In the heart of the recipient fetus there was a chronic myocardial infarction near the apex cordis on the anterior wall with an aneurysm 4x5 mm in diameter. diagnosis was based on light microscopic examination. The poor myocardial systolic function resulted in hydrops. Since the mother was administered beta sympathomimetics in therapeutic doses the contribution of the drug to the myocardial infarction is uncertain, but we would like to suggest this as a possible adverse effect in TTTS. The present case is the first reported myocardial infarction in connection with the syndrome.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
5/21. Percutaneous ultrasonographically guided ablation of an acardiac twin.Acardiac twinning is caused by twin reversed arterial perfusion (TRAP). Normal "pump" twins may face early delivery and cardiac decompensation and have a high perinatal mortality. A primagravid patient had serial evaluation of a TRAP pregnancy beginning early in the second trimester. Rapid growth of the acardiac sibling, high diastolic velocity Doppler waveforms in the perfusing vessel, and early hydramnios prompted ablation of blood flow by a percutaneous ultrasonographically guided infusion of absolute alcohol. A term birth of a normal pump twin was the outcome. Ablation of blood flow into an acardiac sibling of a TRAP pregnancy may be indicated in cases with a poor prognosis by use of an effective percutaneous ultrasonographically guided technique.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
6/21. Antenatal necrotic injury in severe twin-to-twin transfusion syndrome. A case and review.A case of twin-to-twin transfusion syndrome (TTTS) was associated with ischemic injury of the left leg of the recipient twin. Five reduction amniocenteses were performed between 17 6/7 and 23 3/7 weeks followed by fetoscopic laser ablation of chorioangiopagus vessels at 23 6/7 weeks of gestation. Anatomic assessment of the affected limb indicated timing of the injury at 19 4/7 weeks gestational age. The published literature suggests that ischemic fetal injuries in severe TTTS are associated with blood hyperviscosity in the affected twin.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
7/21. Acardiac twin with externalized intestine adherent to placenta: unusual manifestation of omphalocele.TRAP (twin reversed arterial perfusion) syndrome produces an acardiac twin (acardiac monster, acardius, acardiacus, chorioangiopagus parasiticus, etc.). Acardiacs result from monozygotic multiple births in which three anatomic anomalies occur: (1) a fetus' cardiac development is disturbed; (2) artery-artery anastomosis carries blood from a normal ("pump") twin to the acardiac; (3) vein-vein anastomosis carries blood from the acardiac back to the normal twin. Whether reversal of blood flow in the acardiac results from or causes cardiac dysmorphogenesis has not been resolved. Acardiac twins demonstrate a complex constellation of malformations usually thought to result from reversed blood flow; omphalocele is particularly common. We report monochorionic monoamnionic male twins in which an acardiac twin demonstrated externalized intestines adherent to the placenta. The twins were delivered from a 30-year-old primigravida mother by cesarean section without maternal complications at 33 w. The mother has no significant past medical history. The macerated acardius had a 4-cm long attenuated umbilical cord with indeterminate number of vessels. Structures rostral to the thorax were absent save for one poorly developed hand and arm. The abdomen contained loose mesenchyme and no organs. The entire intestine (21 cm) along with two testes was located in a sac on the surface of the placenta. No histopathologic anomalies of formed structures were identified aside from spatial relationships and incomplete development. The normal twin required no intensive care and is doing well. To our knowledge, this is the first report of externalized intestine, which may represent an unusual consequence of omphalocele.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
8/21. Intrafetal alcohol chemosclerosis of acardiac twins: a multicenter experience.OBJECTIVE: To report a multicenter experience with intrafetal alcohol chemosclerosis in the treatment of pregnancies complicated with the twin reversed arterial perfusion sequence. methods: Percutaneous injection of 1- 2 ml of absolute alcohol into the intra-abdominal segment of the single umbilical artery was performed in 8 acardiac twins. Cases were collected from 5 centers following a standardized protocol. The procedure was performed under continuous ultrasound control, using color Doppler ultrasound to identify the main arterial vessel entering the abdomen of the acardiac twin and passing a 20-gauge spinal needle into the targeted vessel. Intraoperative and short-term complications were noted. Information on pregnancy outcome was obtained by reviewing the medical records or contacting the referring obstetrician. RESULT: At the time of the procedure, the acardiac twin was severely hydropic and the size exceeded 70% of the size of the pump twin in all cases. In addition, there were associated complications in all the pump twins including polyhydramnios in 8 cases (100%), cardiac insufficiency in 5 (63%), and fetal growth restriction in 1 (13%). The procedure was performed at a mean gestational age of 24.7 weeks (range 20-32), and it was technically successful in all cases. However, it was complicated with thrombosis of the umbilical vessels of the pump twin in 1 case, and transient bradycardia in 2 others. These 3 pump twins died in utero as a result of the procedure. The other 5 procedures were technically and clinically successful, resulting in an overall survival rate of 63%. In 4 pregnancies, the pump twin was delivered after 35 weeks and had no neonatal complications. CONCLUSIONS: Intrafetal alcohol chemosclerosis is a simple procedure that can be performed in any fetal medicine center around the world to stop the vascular supply to acardiac twins. However, the main concern with this technique is intravascular transfer of the ablative material to the circulation of the pump twin. The use of this technique should therefore be restricted to those pregnancies with poor prognostic factors and in countries where more sophisticated methods for the treatment of this condition are not available.- - - - - - - - - - ranking = 3keywords = vessel (Clic here for more details about this article) |
9/21. foot necrosis in a surviving fetus associated with twin-twin transfusion syndrome and monochorionic placenta.Twin gestations with diamniotic monochorionic placentas have increased perinatal morbidity. We report a case in which, following the death of one member of a set of twins, absent end-diastolic flow was noted. At delivery, we noted thrombosis of placental vessels and vascular connections between the placental vessels of the larger and the smaller twins. The surviving twin was also noted to have necrosis of the right foot, consistent with a thromboembolic phenomenon.- - - - - - - - - - ranking = 2keywords = vessel (Clic here for more details about this article) |
10/21. Effects of ischaemia and hypoxia on the development of the nervous system in acardiac foetus.The twin-reversed arterial perfusion (TRAP) sequence and development of an acardius are rare and severe complications in monozygotic twin pregnancy. Haemodynamic disturbances in placental perfusion via abnormal vascular anastomoses allow inter-twin transfusion to occur. Because of blood perfusion, one of the twins is poorly oxygenated and contains metabolic waste products. Retrograde placental perfusion leads to the formation of a non-viable malformed acardiac foetus. We studied the effects of haemodynamic disturbances in acardiac foetus on the development of the nervous system. The acardius was a product of a 32-weeks pregnancy. Caesarean section yielded a skin covered ovoid mass (size, 10 x 8 cm; weight, 220 g). The dissection of the acardiac twin showed a skin with hair and appendages, rudimentary lower limbs, vertebral column and brain mass. The rudimentary brain tissue was considerably disorganised structurally. We distinguished two main morphological forms of various appearances. In the centre, we observed a scarcely vascularised mass of tissue containing mature and immature neurones, glial cells and randomly distributed fibres. The mass of tissue appeared poorly differentiated, although there were some arrangements reminiscent of cerebral structures. Clusters of neurones provided a slight suggestion of nuclear or fibre structure. The cerebellar cortex was the only well recognisable structure. In the other fragment of the tissue, we found a slit cavity with ependymal outline and well-developed choroid plexus, which seemed to represent the 3rd ventricle. The scarcely vascularised disorganised tissue was surrounded by the highly vascularised one. It included many thin-walled sinusoid vessels. In some places, they were so concentrated that they resembled cavernous haemangioma. The spinal cord appeared comparatively well organised with a slightly dilated central canal. The morphological picture of the rudimentary brain tissue was similar to the picture of the cerebrovasculosa area. The effect of ischaemia in the presented case is the anomalous formation of the cerebral structures. The morphological features imply that the failure occurred after neurulation and before the prosencephalic began to grow. The failure of neural tube formation occurred on the 22nd-25th day of gestation. The malformed formation of the nervous system might be caused by impaired induction due to altered gene expression or to the interference of exogenous agents that interrupt normal development. The haemodynamic abnormal placental circulation, which induced lack of oxygen supply and nutritional deficiency, implies the morphological pattern of the anomaly.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
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