Atıl Yüksel

Dandy-Walker Malformation: A Review of 78 Cases Diagnosed by Prenatal Sonography

Objective: The purpose of this study was to determine the associated abnormalities and clinical outcomes of fetuses with Dandy-Walker malformations. Methods: Sonograms and medical reports of 78 cases were reviewed and information regarding each outcome was collected from autopsy records, hospital charts and specialists caring for the surviving infants. Results: We identified 64 fetuses with classic Dandy-Walker malformation (DW) and 14 fetuses with Dandy-Walker variant (DWV). A high proportion (44.8%) of the parents were consanguineous. The spectrum and proportion of central nervous system (67.1 vs. 71.4%; p = 1.0) and other malformations (43.7 vs. 64.2%; p = 0.57) associated with DW and DWV were similar. Chromosome abnormalities were found in 9 of the 51 (17.6%) fetuses that underwent karyotype analysis. Only 4 of 64 (6.2%) DW and 3 of 14 (21.4%) DWV infants survived (p 0.14), and all surviving infants with DW or DWV had neurological disorders. Conclusions: DW and DWV cases show so many similarities that a clear-cut distinction is difficult. There was no significant difference in the spectrum of associated anomalies and postnatal prognosis between DW and DWV cases.

Fetal cerebellar hemorrhage in a severely growth-restricted fetus: natural history and differential diagnosis from Dandy–Walker malformation

This is a report of an intracerebellar hemorrhage in a severely growth‐restricted fetus with pathological Doppler findings of the fetal and uteroplacental circulations. The diagnosis was made sonographically at 22 weeks of gestation and the natural course of the hemorrhage was followed. Interestingly, the final sonographic appearance of the posterior fossa was quite similar to that of the classic form of Dandy–Walker malformation: absence of the vermis and an enlarged fourth ventricle. However, careful sonographic examination showed that the enlargement of the fourth ventricle was actually caused by a porencephalic cystic lesion of the left cerebellar lobe. Pathological examination revealed complete absence of the vermis and cerebellar hypoplasia. Copyright

Prenatal diagnosis of diastematomyelia: presentation of eight cases and review of the literature

Diastematomyelia is a rare form of spinal dysraphism. We present eight cases of diastematomyelia diagnosed prenatally in our institution as well as a review of the literature in order to determine the prognosis of isolated cases of this very unusual condition.

Sonographic Findings of Fetuses with an Empty Renal Fossa and Normal Amniotic Fluid Volume

Objective: To review the antenatal sonographic findings and postnatal follow-up of fetuses with empty renal fossa (ERF) and normal amniotic fluid volume. Methods: Sonographic examinations of 13,705 fetuses were retrospectively analyzed and all fetuses with at least one ERF and normal antenatal amniotic fluid volume were included in this study. Results: Forty cases with antenatal ERF were diagnosed. Prenatal diagnosis consisted of pelvic kidney (n = 24), unilateral renal agenesis (n = 13), horseshoe kidney (n = 2) and crossed fused renal ectopia (n = 1). The prevalence of ERF in the low-risk population approximated 3.2‰. There was no serious renal complication during a mean follow-up period of 30 months except one case of crossed fused renal ectopia requiring hemodialysis. Conclusion: The underlying cause of ERF in the majority of cases with normal amniotic fluid volume is renal ectopia. Prenatal ultrasonography seems to be highly reliable in diagnosing these anomalies. Prognosis is favorable in the absence of additional extraurinary malformations.

Intracranial Ultrasound Abnormalities and Fetal Cytomegalovirus Infection: Report of 8 Cases and Review of the Literature

Objectives: The aim of this study was to evaluate fetal intracranial and other ultrasonographic findings in cytomegalovirus (CMV) infection. Methods: Data on amniotic fluid CMV-DNA-PCR-positive pregnancies detected in our institution between January 2006 and June 2009 were reviewed retrospectively. Fetal biometric measurements, fetal anatomy, amniotic fluid volume, placental thickness and texture were analyzed for abnormalities. Results: Eight fetuses were diagnosed with congenital CMV infection during the study interval. Their mean gestational age at diagnosis was 25.8 weeks (range: 23–29). All fetuses had intracranial abnormalities; increased periventricular echogenicity (n = 7), ventriculomegaly (n = 5), intracranial calcifications (n = 4), intraventricular adhesions (n = 4), thalamic hyperechogenicity (n = 3), mega cisterna magna (n = 3), lissencephaly (n = 2), vermian defect (n = 2) and cerebellar cyst (n = 1). All of them had accompanying extracranial findings, including hyperechogenic bowel (n = 6), cardiomegaly (n = 3), pericardial effusion (n = 2) and hepatosplenomegaly (n = 1). Intrauterine growth retardation was detected in 3 cases. Five pregnancies were terminated, and 1 intrauterine death occurred. The remaining 2 delivered vaginally at term. One of the live-born babies suffers from tetraparesis, mental retardation and autism, and the other has mild hemiplegia. Conclusions: The spectrum of sonographic findings may vary widely in patients with congenital CMV infection in the prenatal period. CMV should be kept in mind in differential diagnosis, particularly in fetuses with intracranial sonographic findings such as ventriculomegaly, calcifications, intraventricular adhesions and increased periventricular echogenicity.

Fetal Nasal Bone Assessment in First Trimester Down Syndrome Screening

Objective: To evaluate the contribution of nasal bone assessment in the first trimester Down syndrome screening. Methods: The fetuses which underwent first trimester screening with nuchal translucency (NT) measurement were evaluated for the absence or presence of nasal bone according to the instructions described by the Fetal Medicine Foundation, London. Results: Among the 1,807 fetuses included in the study, 9 had trisomy 21. The detection rate of Down syndrome with NT measurement was 77.8% (7/9) with a false-positive rate of 4.5%. Incorporation of biochemical tests (PAPP-A, and free β-hCG measurement) into the screening increased the detection rate to 88.9% (8/9) and decreased the false-positive rate to 3.6%. The prevalence of absent nasal bone was 7/1,798 (0.39%) in chromosomally normal fetuses, and 3/9 (33.3%) in Down syndrome fetuses. Sensitivity, specificity, positive predictive and negative predictive values of absence of nasal bone for trisomy 21 are 33.3% (CI: 0.12–0.64), 99.6% (CI: 0.99–0.99), 30% (95% CI: 0.11–0.53) and 99.7% (95% CI: 0.99–0.99), respectively. The positive likelihood ratio of absent nasal bone was 85.6 (95% CI: 26.2–279.5), and the negative likelihood was 0.67 (95% CI: 0.42–1.06). When nasal bone assessment was incorporated into the NT risk assessment or combined test, the detection rate of trisomy 21 was not changed, however, the false-positive rate decreased to 3.4 and 3%, respectively. Conclusion: The absence of fetal nasal bone has a high positive likelihood ratio for Down syndrome in the first trimester screening, and the presence of nasal bone may potentially lower the need for invasive testing.

Prenatal diagnosis of 13q-syndrome in a fetus with dandy-walker malformation

BACKGROUND: Partial deletion of the long arm of the chromosome 13 is a rare chromosomal aberration and may present with microcephaly, colobomata, microphthalmia, distal limb and digital anomalies, cardiac defects, brain and urogenital malformations, anal atresia and growth restriction. CASE: We report such a case in 25th week of gestation referred for sonographic examination which revealed growth restriction, microcephaly, Dandy-Walker malformation, right microphthalmia, micrognathia, marked nuchal edema, four fingers–oligodactyly in feet and in hands with thumb aplasia and ambiguous genitalia. Chromosome analysis identified chromosome 13q deletion [46 XY del (13) (13q31.2/q32.1 → qter)]. Postmortem examination confirmed prenatal findings and showed aniridia, low-set ears, cryptorchidism, and anal atresia. CONCLUSION: Detection of Dandy-Walker malformation, microphthalmia, oligodactyly with thumb aplasia and growth restriction during prenatal ultrasonography should be a reminder of deletion of chromosome 13q and warrant cytogenetic analysis.

Prenatal sonographic diagnosis of fetus in fetu.

Fetus in fetu is a rare form of monozygotic twinning where an immature twin develops parasitically in the other twin. This condition was first described by Johann Friedrich Meckel in 1800.1 It is a rare condition with less than 190 cases reported in the literature, which were mostly diagnosed after birth. Advances in sonography have made the diagnosis of this condition possible in the prenatal period. The prenatal diagnosis was first reported in 1983,2 and only a few cases of antenatal diagnosis of fetus in fetu have been published until now. Here we report a case of fetus in fetu diagnosed by prenatal sonography in the third trimester of pregnancy. A 36-year-old woman, gravida 4, para 3, was referred to our department at 36 weeks’ gestation with a fetal abdominal cystic mass. Amniocentesis had been performed at another center for fetal talipes equinovarus and an abdominal cystic mass at 22 weeks. Chromosome analysis results were normal. Sonography revealed a 36-week fetus with bilateral talipes equinovarus. In the retroperitoneal region of the fetus adjacent to the left kidney and vertebral column, a fluid-filled sac was observed. A solid mass measuring 50 × 35 × 20 mm was “floating” within this cystic structure, which was 50 × 46 × 59 mm in size (Figure 1 and Video 1). Within the mass, a rudimentary spine and extremities representing an anencephalic fetus in fetu were noted (Video 1). Color flow Doppler investigation revealed blood flow through a stalk from the cyst wall to the floating mass (Video 1). Findings were well matched with the diagnosis of fetus in fetu. In the host fetus, there was substantial coiling of the umbilical cord and dilatation of the umbilical vein, suggesting varicosis, at the level of insertion into the fetal abdomen (Figure 2 and Video 2). Three days after our examination, the fetus died in utero at 37 weeks. A dead male fetus weighing 2650 g was delivered vaginally. The postmortem examination findings were consistent with the prenatal sonographic findings. There was substantial thrombosis in the umbilical vein close to the insertion site of the cord to the fetus (Figure 3, A and B). Autopsy findings revealed a solid mass within a fluid-filled sac surrounded by a transparent membrane (Figure 3C). The solid mass was connected to the membrane by a tiny stalk containing vessels. Microscopic examination of the solid mass showed the general characteristics of welldifferentiated tissues of the fetus in fetu, including skin, neuroglial tissue, vertebra, bone, cartilage, and adrenal cortex (Figure 4). Prenatal sonographic findings of fetus in fetu are a fluid-filled sac with a solid portion floating within it. The most common location of a fetus in fetu is retroperitoneal, constituting 80% of cases, but other locations such as scrotal, nuchal, and intracranial have also been described.2–5 Almost all fetus in fetu cases are anencephalic, and most have a vertebral column and limbs. The blood supply is usually a vascular pedicle, which originates from the abdominal aorta or other regional vessels. The use of prenatal magnetic resonance imaging to confirm the prenatal diagnosis of fetus in fetu has also been described.6 Fetus in fetu occurs secondary to unequal division of totipotent cells at the blastocyst stage, causing a small cellular mass to be included in a more mature embryo.4 Molecular analysis using informative genetic markers showed no genetic differences between the host infant and the fetiform mass.7 Although the monozygotic twin theory was generally accepted, it might not be sufficient to explain the occurrence of multiple fetuses in fetu and its association with teratomas.8 Defective implantation of the blastocyst was postulated to be the underlying mechanism.9 A molecular genetic analysis in 2 cases of fetus in fetu showing different methylation patterns between a host infant and fetiform mass has been reported.10 This finding suggested that a blastocyst originating from one zygote may be implanted in the other blastocyst during the process of methylation or after the establishment of methylation.10 The main differential diagnosis of fetus in fetu is teratoma. Fetus in fetu can be distinguished from teratoma by the presence of a vertebra. Teratomas are most commonly seen in the sacrococcygeal or head and neck region, whereas fetus in fetu cases are typically located in the

Neurodevelopmental outcome of 31 patients with borderline fetal ventriculomegaly.

AIM We present the neurodevelopmental outcome of patients with isolated borderline fetal ventriculomegaly. METHODS The present study was carried out at the Department of Pediatric Neurology, Istanbul Medical Faculty, Istanbul University in July-December 2010. Prenatal second trimester detailed ultrasound examinations were performed by obstetricians at the Prenatal Diagnosis Department of Istanbul Medical School, and 31 consecutive patients aged 8-33 months have been included in the study. Four patients with atrial diameters of over 15 mm and three patients with central nervous system development anomalies were excluded from the study. In order to assess the neuromotor development of patients, neurologic examinations and the Bayley Scales of Infant Development (BSID-III) were used. RESULTS Nine patients were female (29%) and 22 were male (71%). In the postnatal period, tuberous sclerosis was found in one patient, Down syndrome in one, and equinovarus foot deformity in one. Atrial diameter was <12 mm in 18 patients and >12 mm in 13. Cranial ultrasounds done in the first postnatal month revealed persisting ventriculomegaly in nine patients. The two patients who scored significantly low in all areas on the Bayley Scales of Infant Development were the patients with Down syndrome and tuberous sclerosis. The one scoring low in the motor area was the patient with the equinovarus foot deformity. The BSID-III scores of the patients whose prenatal ventricle diameter was <12 mm were within normal limits. The four patients showing slight developmental delay were the ones whose cranial ultrasound in the first postnatal month showed persisting ventriculomegaly. CONCLUSION In patients with borderline fetal ventriculomegaly, atrial diameter being more than 12 mm, the condition persisting in the first postnatal month and the presence of accompanying syndromes and malformations all constitute clear risk factors for neurodevelopmental outcome.

Prenatal diagnosis of isolated macrodactyly

Congenital enlargement of one or several digits of the hands or feet, known as macrodactyly, is a rare malformation. True macrodactyly, characterized by overgrowth of all mesenchymal elements, must be differentiated from that due to tumorous enlargement of a single element, as in hemangioma, lymphangioma or enchondroma. Furthermore, macrodactyly may be isolated, but it can also be associated with several syndromes. Here we present a case of prenatally diagnosed isolated true macrodactyly of the second toe of the left foot at 24 weeks of gestation, and discuss the key points in its differential diagnosis and management. Copyright