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R Achiron

Publications and source records attributed to R Achiron.

At least 19 recordsLinked to original sources
PubMed2006

Rotation of the vermis as a cause of enlarged cisterna magna on prenatal imaging.

OBJECTIVES: Dandy-Walker complex is a continuum of developmental anomalies of the posterior fossa which includes vermian rotation. However, vermian rotation alone may be benign. The aim of this study was to describe our experience with sagittal-plane prenatal ultrasound in the diagnosis of rotation of the vermis in cases of suspected enlarged cisterna magna on routine antenatal imaging, and to describe the follow-up of these patients. METHODS: Seven women, who were referred to our ultrasound unit for evaluation of an enlarged fetal cisterna magna and suspected agenesis of the vermis on axial-plane imaging, underwent further multiplanar studies of the posterior fossa and measurements of the vermis. RESULTS: The mean maternal age was 27 (range, 20-33) years and the mean gestational age at diagnosis was 19.5 (range, 18-31) weeks. The standard axial plane image showed a 'direct communication' between the cisterna magna and the fourth ventricle. In the mid-sagittal plane, the vermis was clearly delineated, with posterosuperior rotation. Vermis size was within normal limits for gestational age in all cases. Findings were confirmed by prenatal magnetic resonance imaging (MRI) in two cases and postnatal MRI and/or sonography in five. During a mean follow-up of 4.5 (range, 1-7.5) years, all children developed normally, with no neurological complications. CONCLUSION: The finding of an enlarged cisterna magna on standard- (axial-)plane ultrasound should be evaluated further in the sagittal plane to determine whether the cause is rotation of a normal vermis. This may spare patients unnecessary tests, anxiety and, in some cases, pregnancy termination.

Adult↗
PubMed2006

Management of Kell isoimmunization--evaluation of a Doppler-guided approach.

OBJECTIVE: To assess the role of peak systolic velocity in the middle cerebral artery (MCA-PSV) in the management of pregnancies complicated by Kell isoimmunization. METHODS: Sixteen fetuses were monitored by conventional protocol (Group 1) and eight fetuses by an MCA-PSV-guided protocol (Group 2). The conventional protocol included a weekly ultrasound evaluation and measurement of maternal anti-Kell titers every 4-6 weeks. In Group 2 Doppler assessment of the MCA-PSV was performed at intervals of 4 to 7 days and MCA-PSV>1.5 multiples of the median (MoM) was considered as an indication for fetal blood sampling (FBS). RESULTS: No parameter emerged as a reliable predictor of isoimmunization severity in Group 1. In Group 2, no FBS was necessary in one case since the MCA-PSV values obtained during the follow-up were <1.29 MoM. In two cases the first FBS was already indicated after 1 week of follow-up, but five other fetuses were followed for 3-9 weeks before FBS was indicated. All fetuses with MCA-PSV>1.5 MoM prior to intrauterine transfusion (IUT) had severe fetal anemia on FBS. In fetuses with severe anemia on the first FBS, the MCA-PSV values 7 days before the first FBS were <1.29 MoM (four cases), between 1.29 and 1.5 MoM (two cases) and >1.55 MoM (one case). CONCLUSIONS: In the management of Kell isoimmunization invasive procedures may be avoided by implementing MCA-PSV measurements. Delineation of appropriate intervals between reassessments, the reliability of MCA-PSV following repeated IUTs, and cut-off values for FBS await further study.

Adult↗
PubMed2006

Sonographic detection of fetal cerebellar cavernous hemangioma with in-utero hemorrhage leading to cerebellar hemihypoplasia.

We report the prenatal diagnosis of cerebellar cavernous angioma. Ultrasound examination at 21 weeks' gestation showed a hyperechogenic lesion measuring 12 mm in diameter, occupying most of the right cerebellar hemisphere. At 24 weeks' gestation, significant hypoplasia of the right hemisphere was diagnosed, and the pregnancy was terminated. Pathological evaluation of the lesion revealed extensive hemorrhaging and a rich network of dilated vessels and small capillaries. The right cerebellar lobe was hypoplastic and covered with blood clots. Cerebral cavernous malformation should be considered in the differential diagnosis of hyperechogenic lesions in the fetal cerebellum.

Adult↗
PubMed2004

Outcome of pregnancies complicated by severe ovarian hyperstimulation syndrome (OHSS): a follow-up beyond the second trimester.

UNLABELLED: The main aim of this study was to assess the obstetric complications for those pregnancies that are complicated by ovarian hyperstimulation syndrome (OHSS) and continue beyond the first trimester. We checked also for other related serious events that occurred during the first trimester. METHODS: We included only patients whose pregnancies continued beyond the first trimester and compared them with IVF-treated patients displaying moderate ovarian response. RESULTS: We studied 165 patients with OHSS (101 singletons and 64 twins) and 156 IVF control patients (85 singletons and 71 twins). Two serious complications, gestational diabetes mellitus (GDM) and pregnancy-induced hypertension (PIH), were noted in both groups. However, the incidence of these two complications did not differ significantly between the groups. In the OHSS group, GDM presented with an incidence of 9.9% for singletons and 9.4% for twins, and 12.9% and 7.0%, respectively, for the control group. PIH presented as 6.9% for singletons and 10.9% for twins in the OHSS group, and 8.2% and 7.0%, respectively, for the control groups. During the first trimester laparoscopies for suspected ovarian torsion were performed in 13 patients, and in 10 patients the diagnosis were confirmed. CONCLUSIONS: Although patients with OHSS-complicated pregnancies previously reported a relatively high risk of GDM and PIH, the occurrence rates do not differ from a matched control group of normally responding patients who conceived after IVF.

Adult↗
PubMed2004

Tailored management of twin reversed arterial perfusion (TRAP) sequence.

OBJECTIVE: To describe our management of pregnancies complicated by twin reversed arterial perfusion (TRAP) sequence. METHODS: This was a retrospective study involving all cases of TRAP sequence referred to our fetal medicine unit in a 3-year period (2000-2002). Patients were routinely managed by repeat sonographic surveillance with sonographic anatomical evaluation and detailed echocardiography. Cases with signs of impending cardiac failure were treated by in-utero YAG-laser coagulation of the umbilical vessels of the acardiac twin. RESULTS: Six cases were studied. Three patients in whom there were no signs of deterioration in the status of the pump twin, and in whom the acardiac twin was smaller than the pump twin, were managed conservatively. However, one of these with monoamniotic twins ended in intrauterine fetal death of the pump twin. The other two cases presented with spontaneous cessation of blood flow in the umbilical artery of the acardiac twin. Both delivered at term normal neonates whose follow-up revealed no signs of neurological sequelae. One case of quadruplet pregnancy (with TRAP sequence and two dichorionic twins) was treated by selective termination of the monochorionic twins. Two cases with signs of impending cardiac failure were treated by in-utero YAG-laser occlusion of the vessels in the acardiac mass. Both interventions had a favorable outcome. CONCLUSIONS: Conservative treatment is suitable for milder cases of TRAP sequence in which the pump twin is the larger one. Cases in which the acardiac twin is larger have a poorer prognosis and should be treated by invasive intervention and cord occlusion.

Adult↗
PubMed2004

Fetal lung dysplasia: clinical outcome based on a new classification system.

OBJECTIVE: To evaluate the clinical application of a new classification system of fetal lung anomalies. METHODS: Forty fetal diagnoses of lung lesions were analyzed according to our proposed classification system in which each lung component is considered using two-dimensional ultrasound and color and power Doppler technology. Medical files, natural history and neonatal follow-up were recorded. RESULTS: Type I dysplasia: Four cases of agenesis of the lung were diagnosed, three with right lung agenesis and one with left lung agenesis. Three of the four patients elected to undergo termination of pregnancy (TOP). The surviving fetus was diagnosed with scimitar syndrome and postnatal embolization of the aberrant vessel was performed. Type II dysplasia: One case of normal lung with abnormal systemic feeding artery was diagnosed with normal neonatal outcome. Type III dysplasia: Abnormal lung with abnormal vascularity was found in 14 cases, presenting in most cases as echogenic lung masses. Seven were supradiaphragmatic, six subdiaphragmatic and one case was of undetermined position. All 14 fetuses showed an aberrant systemic artery emerging from the aorta. Abnormal venous drainage could be identified in only five (36%) of the fetuses: three had prominent azygos vein, one showed drainage to the inferior vena cava and one had multiple intrapulmonary veins forming a huge arteriovenous (A-V) shunt. Two cases in this group underwent TOP, the case with A-V shunt following development of hydrops, and one on maternal request. The remaining 12 fetuses (86%) survived and were alive and well at the time of writing; only one of them needed immediate postnatal embolization of the bilateral aberrant feeding arteries. Type IV dysplasia: Abnormal lung with no vascular abnormality was diagnosed in 20 fetuses. In this group there was one case of intrauterine fetal death, two patients underwent TOP, one complicated with hydrops and one on maternal request. The survival rate in this group was 85%. Only two cases needed immediate surgical repair. Type V miscellaneous dysplasia: One fetus demonstrated echogenic lung with split notochord syndrome and survived. CONCLUSIONS: Congenital bronchopulmonary and related vascular anomalies can be categorized using the new classification system. This new approach enabled prenatal evaluation of each lung component and facilitated cogent management of the fetus with congenital lung dysplasia.

Blood Vessels↗
PubMed2004

Development of the human fetal pons: in utero ultrasonographic study.

OBJECTIVES: To examine the ultrasonographic feasibility of imaging the fetal pons and to construct a reference chart for its normal development during gestation. METHODS: A cross-sectional, prospective study on 293 healthy fetuses of low-risk pregnancies between 19 and 34 weeks was performed. The transfontanel approach, via the abdominal or vaginal routes, was used to evaluate the fetal metencephalon (pons and cerebellum). The anteroposterior diameter of the fetal pons was measured in a mid-sagittal plane. The longitudinal diameter of the cerebellar vermis was measured at the same plane and the vermis-pons ratio (VPR) was established. RESULTS: One hundred and forty-four fetuses were in vertex position. In 140 (97.2%) satisfactory visualization and measurements of the pons and cerebellar vermis were obtained. One hundred and forty-nine fetuses were breech presentations and measurements were successfully performed in 147 (98.6%). The pons anteroposterior and vermis longitudinal diameters showed a linear correlation with gestational age (GA) (r = 0.95 for both measurements; P < 0.001). The mean VPR was 1.5 (+/-0.1 SD) and did not change in the gestational interval that was considered. CONCLUSION: By using the transfontanel approach, evaluation of the fetal pons is feasible via the mid-sagittal plane. The nomograms developed and the ratio to fetal vermis provides reference data that may be helpful when evaluating anomalies of the brainstem.

Cross-Sectional Studies↗
PubMed2003

The progestative effect of the levonorgestrel-releasing intrauterine system--when does it manifest?

The objective of the study was to evaluate, clinically and sonographically, the time required for the progestative effect of the levonorgestrel-releasing intrauterine system (IUS, Mirena) to be manifested. Doppler flow of the cervical branch and spiral artery of the uterine artery, as well as the endometrial width (up to day 10 of the cycle), were evaluated in 36 women carrying levonorgestrel-releasing IUS 1-2 months after insertion of the device compared to 4-6 months after insertion. The rate of intermenstrual bleeding was reduced from 44% during the first 2 months, to only 8% of women after 4-6 months of use. Complete cessation of menstrual bleeding occurred in 5% after 2 months and in 66% after 4-6 months following insertion. While there was no change in the Doppler flow in the cervical branch of the uterine artery between both groups, there was a significant reduction in the subendometrial flow in the spiral artery. This observation was reinforced by the demonstration of significant reduction in endometrial thickness in the following 4 months of use. The present study has demonstrated that the local progestative effect of the levonorgestrel-releasing IUS on the endometrium is already manifested within a period of 3 months and over after insertion.

Adult↗
PubMed2002

Poor prenatal detection rate of cardiac anomalies in Noonan syndrome.

BACKGROUND: The wide variation and nonspecific nature of many of the associated ultrasonographic findings complicate prenatal diagnosis of Noonan syndrome. The aim of the present study was to define the rate of prenatal diagnosis of heart malformations in cases diagnosed postnatally with Noonan syndrome. METHODS: English-language literature review of 29 cases of Noonan syndrome examined prenatally with confirmed postnatal diagnosis and four case reports from our center. RESULTS: Cases were evaluated for cervical spine pathologies, cardiac anomalies and other pathological findings, including hydrops fetalis and polyhydramnios. Cardiac anomalies were suspected in only nine of 33 cases; three of these were associated with cystic hygroma. Cardiac anomalies were eventually diagnosed in 31/33 cases postnatally. Polyhydramnios was diagnosed in 19/33 cases in the third trimester, and hydrops fetalis was detected in eight of 33. Cystic hygroma was present in a total of nine cases at mid-trimester. CONCLUSIONS: Noonan syndrome is characterized by late-onset and progressive pathologies, particularly the associated cardiac anomalies, which develop through the course of gestation and postnatal life. This complicates or precludes prenatal diagnosis at mid-trimester or at any time in the prenatal period, and partly explains the low rate of detection of fetal cardiac lesions in this syndrome.

Female↗
PubMed2002

The development of the fetal vermis: an in-utero sonographic evaluation.

OBJECTIVE: To establish a nomogram for fetal vermis measurements during gestation. METHODS: A prospective cross-sectional study of normal singleton pregnancies. Measurements of the fetal vermis width (in the axial plane) and height (in the sagittal plane) were performed by high-resolution transabdominal ultrasonography between 18 and 38 weeks of gestation in 256 fetuses. RESULTS: Adequate vermis measurements were obtained in 256 fetuses. Vermian width and height as a function of gestational age and biparietal diameter were expressed by regression equations and the correlation coefficients were found to be highly statistically significant (P < 0.0001). The normal mean (+/- SD) for each gestational week was defined. CONCLUSIONS: The present data offer the normal range of the vermian measurements throughout gestation. These values may allow intrauterine assessment of the development of the cerebellar vermis, as well as the posterior fossa.

Cerebellum↗
PubMed2002

The three vessels and trachea view (3VT) in fetal cardiac scanning.

OBJECTIVE: Comprehensive evaluation of the fetal heart has become a major part of targeted organ scanning to rule out fetal malformations. Evaluation of the mediastinal major vessels seems to be the most difficult and time-consuming part of fetal heart examination. Our aim was to define and evaluate the three vessels and trachea (3VT) view, a novel and simple method to examine the great vessels in the mediastinum, and its applicability in the clinical practice of fetal echocardiography, while establishing nomograms for cardiac vessel measurements obtained in this view. METHODS: The three vessels and trachea view was examined in 379 low-risk gravidae between 14+0 and 23+6 weeks' gestation. Six parameters in this plane were measured to establish nomograms. In another group of 984 mixed high- and low-risk patients we compared the time required to identify the aortic arch using the 3VT view as compared to the long-axis view. RESULTS: The 3VT view was readily and satisfactorily demonstrated in all but two of the 1363 cases examined. In 17 cases (out of a total of 982) more than 10 min were required to identify the aortic arch using the 3VT view and in 71 patients when employing the long-axis view (P < 0.001). CONCLUSION: The clinical applicability of the 3VT view to evaluate the anatomy of the major vessels in the mediastinum is demonstrated. Although a wide variation in the six parameters of the 3VT view used here precludes their use in diagnosing great vessel anomalies, some of the ratios between them have promising potential in the evaluation of great vessel malformations. Further, the 3VT view seems to be more efficient in identifying the aortic arch than does the long-axis view.

Adult↗
PubMed2002

Anomalies of the fetal aortic arch: a novel sonographic approach to in-utero diagnosis.

OBJECTIVE: To describe a novel, sonographic approach for in-utero evaluation of normal and abnormal aortic arch. METHODS: Aortic arch was evaluated by imaging of the axial view of the upper fetal mediastinum. The normal left aortic arch was defined by the V-shaped appearance of the junction between the ductus arteriosus and aortic arch, with the trachea situated posteriorly. Right and double aortic arches were diagnosed when the great vessels appeared U-shaped, with intermediate location of the trachea. RESULTS: Between 1997 and 1999, 18 347 women were scanned in three prenatal centers, and pathological findings were prospectively recorded. In a retrospective analysis of the records, we identified 19 fetuses (0.1%) with atypical, U-shaped appearance, and no other structural abnormalities present. With the exception of one fetus with a ventricular septal defect, no congenital cardiac defects were present. Right aortic arch was found in 18 cases, while color Doppler made it possible to diagnose one case with double aortic arch, and one fetus was demonstrated as having Kommerell's diverticulum. In all 18 cases, a left descending aorta and left ductus arteriosus were present, the latter coursing to the left of the trachea, forming a loose partial vascular ring. All were asymptomatic at birth and early infancy. The fetus with double aortic arch that had a true vascular ring underwent early infantile correction. CONCLUSIONS: It is possible to diagnose right and double fetal aortic arch using prenatal ultrasound. The use of color Doppler facilitated in-utero evaluation of possible complications, such as true vascular ring.

Adolescent↗
PubMed2002

The local progestational effect of the levonorgestrel-releasing intrauterine system: a sonographic and Doppler flow study.

BACKGROUND: We aimed to evaluate the effect of the levonorgestrel-releasing intrauterine system (LNG-IUS) on the uterine vasculature and the endometrium. METHODS: The study was a prospective controlled study evaluating the local effects of LNG-IUS compared with the copper intrauterine device (IUD). Forty-seven women carrying LNG-IUS (group A) were compared with 35 women carrying copper IUD in a control group (group B). Clinical measures of menstrual bleeding, endometrial thickness and Doppler flow of the cervical branch of the uterine artery and spiral artery were evaluated and compared between the two groups. RESULTS: Doppler flow in the cervical branch of the uterine artery did not reveal any changes between the groups (resistance index = 0.6 +/- 0.01 in both groups). Endometrial width was significantly thinner in group A (4.1 +/- 0.2 mm) compared with group B (7.3 +/- 0.2 mm) (P < 0.0001). Subendometrial flow in the spiral artery was significantly reduced in 35 women of group A (75%) and in none of group B (P < 0.0001). CONCLUSIONS: The present study offers an explanation for the oligomenorrhoea in LNG-IUS users, i.e. a local progestational effect on the endometrium with no change in the blood flow in the uterine artery. This should be presented to the women in the pre-contraceptive counselling in order to lessen the discontinuation rate.

Adult↗
PubMed2002

Cervical Shirodkar cerclage may be the treatment modality of choice for cervical pregnancy.

BACKGROUND: Our objective was to evaluate the use of cervical suture in cervical pregnancy. METHODS AND RESULTS: All cases of cervical pregnancy diagnosed and treated in the gynaecological department at the Sheba Medical Center between 1994-2000 were included in the study. Eight such cases were diagnosed. The first four cases were treated medically. The last four cases (the study group) of cervical pregnancy, including one case of heterotopic pregnancy, were treated successfully with placement of Shirodkar cerclage. CONCLUSION: Cervical cerclage may be considered as the treatment of choice in cases of cervical pregnancies. It may be the only therapy in cases of heterotopic pregnancies (intrauterine and cervical pregnancy).

Abortifacient Agents, Nonsteroidal↗
PubMed2001

Antenatal sonographic findings of right pulmonary agenesis with ipsilateral microtia: a possible new laterality association.

Right pulmonary agenesis is a rare congenital malformation which results in secondary dextrocardia in situs solitus. Ipsilateral microtia in this context composes a laterality syndrome. The prenatal sonographic findings of this abnormality have not been previously reported. We describe the association of dextrocardia in situs solitus, intact diaphragm and right microtia. This was sonographically diagnosed at mid-gestation in an euploid fetus. Surgical evacuation of the pregnancy confirmed the external malformation. Laterality association should be assessed in a fetus with sonographic findings of pulmonary agenesis. The differential diagnosis and updated literature review is presented.

Adult↗
PubMed2001

Split notochord syndrome - prenatal ultrasonographic diagnosis.

Split notochord syndrome is a rare condition that is characterized by a persistent connection of the gut and dorsal skin of the back, an enteric cyst and vertebral anomalies. We present two cases in which prenatal ultrasound showed polyhydramnios. In one case it was associated with vertebral abnormalities and a right-sided mediastinal cyst found to be the stomach. Postnatal evaluation confirmed the diagnosis of split notochord syndrome. The association of sonographic findings of hydramnios, thoracic cysts and vertebral anomalies suggests prenatal diagnosis of split notochord syndrome.

Adult↗