Prenatal diagnosis of schizencephaly by fetal magnetic resonance imaging.

Schizencephaly is a neuronal migration anomaly characterized by gray matter lined clefts extending from the ventricle to the cortical surface leading to specific lesions, well demonstrated by imaging. The lips of the clefts can be fused or separated. Prognosis is related to the extend of the involved cortex. Both genetic and acquired factors can be responsible for this pathology. Three cases of antenatal diagnosed open schizencephaly are reported. Two cases are unilateral and one is bilateral. A cerebral anomaly has been detected in all cases by routine ultrasonography (US) revealing a ventricular dilatation with cortical associated abnormalities. Prenatal magnetic resonance imaging (MRI) permitted the diagnosis in the 3 cases. All cases had led to abortion because of the importance of the cortical defect. The aim of this report is to point out the importance of fetal MRI in the diagnosis of migration disorder and to discuss the medical implications. Indeed, MRI is better suited than US for the prenatal diagnosis of schizencephaly, being able to detect normal and abnormal brain cellular migration, especially with fast imaging (HASTE sequences). With its multiplanar imaging capability, MRI demonstrates the cleft extending from the pial surface to the ventricular ependyma and thus provides characteristic diagnosis of this disorder. Moreover, ventricular dilatation, a frequent anomaly detected by US should be completed with MRI in order to research a neuronal migration disorder.     

Prenatal diagnosis of sacrococcygeal teratoma with constitutional partial monosomy 7q/trisomy 2p

We report the prenatal diagnosis of a fetus with sacrococcygeal teratoma and facial dysmorphism attributed to a constitutional terminal deletion of chromosome 7q and partial trisomy of chromosome 2p likely resulting from a de novo balanced translocation. The cytogenetic abnormality was diagnosed prenatally after sonographic detection of teratoma and confirmed on peripheral blood cells at birth. The newborn died of post-operative complications at seven days of age. FISH analysis demonstrated haploinsufficiency of HLXB9, a gene identified in the triad of a presacral mass (teratoma or anterior meningocele), sacral agenesis, and anorectal malformation, which constitutes the Currarino syndrome. Despite the absence of other features of the triad, the teratoma observed in the fetus we describe might represent a partial form of Currarino syndrome.     

Prenatal diagnosis of fetal cerebral abnormalities by ultrasonography and magnetic resonance imaging

We found magnetic resonance imaging (MRI) of the fetal brain to be effective in confirming or denying diagnosis of fetal cerebral defects when ultrasonography was inconclusive or incomplete. In this paper we describe 31 cases in which ultrasonographic evidence of fetal brain defects was verified by MRI. MRI was performed after curarization of the fetus. In 21 cases, ultrasonographic evidence was confirmed by histological study of the fetus or postnatal radiological examination. In 10 cases, ultrasonographic diagnosis was denied by MRI and healthy infants were born. In one case of cerebral toxoplasmosis, ultrasonography detected periventricular calcifications but MRI was normal. In 20 cases MRI ascertained or further documented the ultrasonographic findings. However in 4 of these 20 cases autopsy of the fetus was required to determine the exact nature of the lesion.     

磁共振检查在脑室扩张胎儿产前诊断中的作用

目的:探讨磁共振成像(MRI)在超声提示脑室扩张胎儿产前诊断中的作用。方法:选择因超声提示单纯性脑室扩张而行MRI检查者,对MRI结果进行分析并随访妊娠结局。结果:1 MRI结果的准确性:入组病例MRI对超声的总补充诊断率为15.4%(38/247),其中脑积水11例,脑室扩张伴脑出血3例,脑室扩张伴胼胝体发育不全(ACC)9例,室管膜下囊肿(或蛛网膜囊肿)9例,DandyWalker等其他类型畸形6例。2胎儿脑室扩张的宫内转归及新生儿预后:63.2%(24/38)有结构畸形者选择引产,均未见染色体核型异常。正常分娩新生儿155例,新生儿随访无异常神经系统表现。结论:对于脑室扩张,尤其是重度脑室扩张,MRI对于超声有极高的补充诊断价值。     

7号染色体末端三体和13号染色体末端单体致胎儿多发畸形的产前诊断

目的:产前诊断1例胎儿宫内发育迟缓、先天发育异常,脑积水,丹迪沃克综合征,脊柱裂,先天性心脏病,足内翻等的原因,为再次妊娠提供信息。方法:用常规G显带技术分析胎儿羊水染色体及其父母外周血染色体,并用多重连接探针扩增技术(MLPA)和微列阵比较基因组杂交芯片(array-CGH)进行精确分析。结果:胎儿13号染色体出现异常,具体异常情况不明确。MLPA检测显示,胎儿13q32-34出现缺失;array-CGH进一步分析显示,胎儿7号染色体部分三体,重复区域为q31.33-q36.3,片段大小34.74Mb,13号染色体部分单体,缺失区域为q31.3-q34,片段大小为25.88Mb;胎儿的异常染色体来源于父亲。结论:7q部分三体和13q部分单体是胎儿异常表型的主要原因,MLPA技术在产前胎儿检测中起着高效价廉的筛选作用,array-CGH为明确微小重复和缺失提供了技术手段。     

Prenatal diagnosis of fetal arrhythmias

Life-threatening fetal arrhythmias are rare and warrant sophisticated specialty prenatal care, often provided by maternal-fetal medicine obstetricians, and pediatric and adult cardiologists. This medical field is in quick transition, and new methods of diagnosis and treatment of the fetus with arrhythmias are emerging. In this article, the mechanisms of arrhythmias are presented in light of recent progress in the new field of fetal electrophysiology. Treatments are reviewed with recommendations based on the small number of series of fetal tachycardia and fetal atrioventricular (AV) block drug treatment strategies published to date. Finally, a summary of areas of potential future research is provided.     

Prenatal diagnosis of monosomy 18 and ring chromosome 18 mosaicism.

The case of monosomy 18/ring chromosome 18 mosaicism which was detected prenatally by amniocentesis is presented. The pregnancy was terminated in week 18. Autopsy showed complex malformation of the fetus consisting of cebocephaly, hypotelorism, microphthalmia, severe defects of brain development, and arrest of placental maturation.     

Prenatal foetal diagnosis of partial trisomy 3q and monosomy 13p due to a maternal balanced rearrangement

The authors describe a case of a male foetus whose ultrasound at 20 weeks' gestation revealed cystic hygroma, cleft lip and ventricular septal defect. Amniotic fluid cytogenetics using GTG banding showed a 46,XY,der(13)t(3;13)(q12;p11.1) rearrangement, and fluorescence in situ hybridization (FISH) delineated the relevant breakpoints. Familial studies identified a maternal balanced translocation involving chromosomes 3 and 13. The post-mortem examination confirmed the prenatal ultrasound findings.     

The role of magnetic resonance imaging in prenatal diagnosis of fetal anomalies

Magnetic resonance imaging (MR) has become a useful adjuvant in evaluating fetal structural anomalies when ultrasound (US) is equivocal. It has a significant promise in confirming a US suspected abnormality and providing new information that was previously not available.The first studies on prenatal MR were hindered by fetal motion and long acquisition times. This degraded imaging and, therefore, maternal or fetal sedation was needed. Since fast and ultrafast MR with scan times of <1 s have become available, the amount of motion artifacts is decreased and sedation is no longer needed.MR has proved to be especially beneficial in detecting CNS anomalies. Agenesis of the corpus callosum, migration abnormalities and abnormalities of the posterior fossa are better seen on MR. Masses in the fetal neck and thorax can be identified on MR, as some abdominal anomalies. However, the fetal skeletal is difficult to visualize with MR.In the future, it is most likely that real time MR will become clinically available which would improve MR imaging even more.     

Prenatal imaging of fetal hepatoblastoma.

A detailed sonographic at 37 weeks of gestation performed due to non-reassuring fetal monitor of a breech presentation fetus detected a solid right lobe hepatic tumor. Prenatal gray scale and Doppler sonography suggested a diagnosis of hepatoblastoma which was confirmed postnatally. Differential ultrasonographic diagnosis of fetal hepatic tumors is discussed.     

胎儿肾积水的产前超声诊断及预后评估

目的 探讨胎儿肾积水的产前超声诊断的临床意义及其预后评估价值.方法 2004年12月至2005年11月在浙江大学医学院附属妇产科医院就诊的妊娠20周以上的9526例单胎孕妇行常规产前超声检查,发现胎儿肾盂前后径≥8 mm者诊断为肾积水而纳入本研究.并按Grignon分级法进行分级,定期检查和记录妊娠结局,直至分娩.结果 (1)胎儿肾积水的发生率及Grignon分级:9526例中共有162例胎儿发生肾积水,发生率为1.7%.于肾积水高峰期行Grignon分级,1级71例,2级59例,3级7例.4级3例,5级22例.(2)发生肾积水的孕周分布:初次发现胎儿肾积水的孕周平均为(33±5)周.肾积水程度达到最高峰的孕周平均为(36±3)周.110例(68%)胎儿肾积水在妊娠期即自行消失,消失孕周平均为(37±4)周.(3)不良妊娠结局:162例肾积水胎儿中有不良妊娠结局40例(25%),其中11例初次发现于孕20～24周中有3例(27%),20例初次发现于孕25～28周中有6例(24%),53例初次发现于孕29～32周中有14例(26%),48例初次发现于孕33～36周中有11例(23%),30例初次发现于孕37～40周中有6例(20%).胎儿肾积水Grignon分级越高,不良妊娠结局发生率也越高,3级及以上者不良妊娠结局发生率达100%.(4)随访结果 :分娩健康新生儿122例(75%,122/162),为110例出生前肾积水自行消失者和12例出生后1周内肾积水自行消失者,随访2年以上其生长发育正常,无泌尿系统后遗症;分娩肾积水新生儿20例(12%,20/162),为出生后1周内超声复查仍存在肾积水者,其中Grignon分级在3级及以下者11例,肾积水消失时间在出生后3个月至12个月不等,患儿生长发育均与同龄儿无明显差异,无泌尿系统症状.结论 胎儿肾积水初次发现的孕周越早,程度越严重,胎儿预后越差.应用Grignon分级法对胎儿肾积水程度进行分级可用于评估肾积水胎儿的预后,以指导临床处理.