Prenatal diagnosis of craniomaxillofacial malformations: a characterization of phenotypes in trisomies 13, 18, and 21 by ultrasound and pathology

Epidemiological characteristic of Orofacial clefts and its associated congenital anomalies: retrospective study

BACKGROUND

To evaluate the relationship between gender, ethnicity/citizenship, clinical phenotype, total prevalence, and the various congenital malformations associated with oral clefts (OC) in Italy across the period 2001-2014.

METHODS

A retrospective analysis (2001-2014) was conducted based on the National Congenital Malformation Registries network of Italy (Emilia-Romagna Registry of Birth Defects [IMER] and Registro Toscano Difetti Congeniti [RTDC]), which were analyzed to investigate time trends, geographical/ethnic clusters, topography, sex ratio, and associated congenital anomalies of OC phenotypes.

RESULTS

Among 739 registered cases, 29.8% were syndromic or had multi-malformed associated anomalies, compared with 70.2% having isolated orofacial cleft. Cleft lip (CL) was observed in 22%, cleft palate (CP) in 40%, and cleft lip and palate (CLP) in 38% of live births, stillbirths, and terminations of pregnancy for fetal anomaly cases. Other associated conditions were major anomalies of cardiovascular defects (39%), followed by defects of the limbs (28%), neuroectodermal defects (23%), and urogenital malformations (10%). Male-to-female sex ratio was 1:1.14 in CP, 1.22:1 in CL, and 1.9:1 in CLP. Foreigners were represented by 29% from Southeast Asia, 25% from Balkans, 25% from North-Central Africa, 9% from the East, 7% from Western Europe, and 5% from South America. Total prevalence of OC cases ranged from 0.9 (RTDC) to 1.1 (IMER) of 1000 births.

CONCLUSIONS

This retrospective study provides a population-based, clinical-epidemiological description of the orofacial cleft phenomenon. As a relatively frequent congenital malformation, its social and economic impact is worthy of further study. These abnormalities can cause significant problems that may be solved or minimized by early diagnosis and treatment.

The human brain and face: mechanisms of cranial, neurological and facial development revealed through malformations of holoprosencephaly, cyclopia and aberrations in chromosome 18

The study of inborn genetic errors can lend insight into mechanisms of normal human development and congenital malformations. Here, we present the first detailed comparison of cranial and neuro pathology in two exceedingly rare human individuals with cyclopia and alobar holoprosencephaly (HPE) in the presence and absence of aberrant chromosome 18 (aCh18). The aCh18 fetus contained one normal Ch18 and one with a pseudo-isodicentric duplication of chromosome 18q and partial deletion of 18p from 18p11.31 where the HPE gene, TGIF, resides, to the p terminus. In addition to synophthalmia, the aCh18 cyclopic malformations included a failure of induction of most of the telencephalon - closely approximating anencephaly, unchecked development of brain stem structures, near absence of the sphenoid bone and a malformed neurocranium and viscerocranium that constitute the median face. Although there was complete erasure of the olfactory and superior nasal structures, rudiments of nasal structures derived from the maxillary bone were evident, but with absent pharyngeal structures. The second non-aCh18 cyclopic fetus was initially classified as a true Cyclops, as it appeared to have a proboscis and one median eye with a single iris, but further analysis revealed two eye globes as expected for synophthalmic cyclopia. Furthermore, the proboscis was associated with the medial ethmoid ridge, consistent with an incomplete induction of these nasal structures, even as the nasal septum and paranasal sinuses were apparently developed. An important conclusion of this study is that it is the brain that predicts the overall configuration of the face, due to its influence on the development of surrounding skeletal structures. The present data using a combination of macroscopic, computed tomography (CT) and magnetic resonance imaging (MRI) techniques provide an unparalleled analysis on the extent of the effects of median defects, and insight into normal development and patterning of the brain, face and their skeletal support.

Facial profile markers in second- and third-trimester fetuses with trisomy 18

OBJECTIVES

To evaluate nasal bone length (NBL), maxilla-nasion-mandible (MNM) angle, fetal profile (FP) line, prenasal thickness (PT), prenasal thickness to nasal bone length (PT:NBL) ratio and prefrontal space ratio (PFSR) as markers of trisomy 18 in the second and third trimesters of pregnancy.

METHODS

The NBL, MNM angle, FP line, PT, PT:NBL ratio and PFSR were measured retrospectively from stored two-dimensional images or three-dimensional volumes of trisomy-18 fetuses, and were compared with our previously reported normal ranges for euploid fetuses. Additional ultrasound findings were noted at initial routine second-trimester scan and at subsequent advanced ultrasound examination performed after referral for karyotyping.

RESULTS

A total of 43 trisomy-18 fetuses were included in the analysis. At initial examination, median gestational age was 21 + 2 weeks. NBL and PT were correlated with gestational age (P < 0.001), but the other markers were not. Mean NBL, MNM angle, PT, PT:NBL ratio and PFSR were 3.76 mm, 16.67°, 4.25 mm, 1.39 and 0.87, respectively. The FP line was zero (normal) in 53.7% of cases and negative (abnormal) in 46.3%. All markers were significantly associated with trisomy 18, with the PT:NBL ratio yielding the highest detection rate (88.4%) followed by NBL (83.7%), MNM angle (56.4%), FP line (46.3%), PT (27.9%) and the PFSR (20.5%) (for a 5% false-positive rate for the continuous variables). Various combinations of the four best markers (NBL, FP line, MNM angle and PT:NBL ratio) yielded detection rates of between 72% and 95%. Structural anomalies were not detected in 22% of fetuses at the initial scan and in 2% at the advanced scan.

CONCLUSIONS

The PT:NBL ratio and NBL are robust second- and third-trimester markers for trisomy 18. A negative FP line has a 0% false-positive rate and the potential to differentiate between trisomy 18 and Down syndrome, as in the latter the FP line is often positive. No major anomaly was observed at the initial scan in about a quarter of trisomy-18 fetuses, underlining the role of second-trimester facial marker evaluation.

Prenatal diagnosis and management of nasal glioma

Advances in foetal imaging have increased our detection rate of craniofacial abnormalities in utero. Nasal glioma is a rare, benign, congenital facial defect. Once detected, further imaging is required to assess for intracranial communication, the presence of additional defects, determine the patency of the aerodigestive tract and decide on timing of delivery. The authors review the current literature on diagnosis and management of nasal glioma in this rapidly advancing field of craniofacial anomalies detected in utero. Literature search of EMBASE and MEDLINE databases yielded 594 articles, which were screened by 2 independent reviewers. A total of 7 papers were selected after exclusion. There have been seven cases of prenatally diagnosed nasal glioma. The earliest of these was detected at 20 wk gestation. The majority were investigated with foetal magnetic resonance imaging (MRI) to establish any intracranial communication or bony defects. Ultrasound monitoring, doppler waveform and 3D rendered images were utilised to delineate the lesion, monitor growth and differentiate potential diagnosis. Postnatal MRI is favoured by most to re-evaluate the lesion and aid surgical planning. Surgical resection was performed within the first few months of life. Diagnostic uncertainty was seen in all cases, until formal histology was obtained, emphasising the challenges, and need for early appropriate specialist input. Whilst the prenatal detection of craniofacial abnormalities increases, there remain diagnostic challenges in differentiating prenatal congenital midfacial defects in utero. These defects are best investigated and monitored using prenatal ultrasound and MRI, to narrow the differential diagnosis, guide timing of delivery and allow for appropriate surgical planning. Prenatally detected nasal glioma, may only be confirmed on histology and families must be counselled appropriately to prepare them for the possible alternative diagnoses. Early surgical resection was undertaken to achieve more favourable aesthetic outcomes, reduce complications of ocular development and provide definitive histological diagnosis.

Prenatal ultrasound screening for external ear abnormality in the fetuses

Objectives. To investigate the best time of examination and section chosen of routine prenatal ultrasound screening for external ear abnormalities and evaluate the feasibility of examining the fetal external ear with ultrasonography. Methods. From July 2010 until August 2011, 42118 pregnant women with single fetus during 16–40 weeks of pregnancy were enrolled in the study. Fetal auricles and external auditory canal in the second trimester of pregnancy were evaluated by routine color Doppler ultrasound screening and systematic screening. Ultrasound images of fetal external ears were obtained on transverse-incline view at cervical vertebra level and mandible level and on parasagittal view and coronal view at external ear level. Results. Five fetuses had anomalous ears including bilateral malformed auricles with malformed external auditory canal, unilateral deformed external ear, and unilateral microtia. The detection rate of both auricles was negatively correlated with gestational age. Of the 5843 fetuses undergoing a routine ultrasound screening, 5797 (99.21%) had bilateral auricles. Of the 4955 fetuses following systematic screening, all fetuses (100%) had bilateral auricles. The best time for fetal auricles observation with ultrasonography is 20–24 weeks of pregnancy. Conclusions. Detection of external ear abnormalities may assist in the diagnosis of chromosomal abnormalities.

Prenatal diagnosis and management of a craniofacial glioma detected at 20 weeks' gestation. Case report and review of the literature

Foetal imaging and anomaly detection is advancing at a rapid rate. As a result, detection of foetal craniofacial abnormalities is increasing. Ultrasound and magnetic resonance imaging are currently the imaging modalities most commonly used. The authors describe the detection of a nasal glioma at 20 weeks' gestation, subsequent prenatal monitoring and postnatal management with surgical excision at 2 months of age. The world literature regarding prenatal diagnosis and management of craniofacial malformations is discussed.