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We report on laryngeal malformations in 5 subjects, 4 females and 1 male, with the autosomal-recessive Richieri-Costa and Pereira form of acrofacial dysostosis. Characteristics of the voice are described.

We describe a stillborn girl with an unclassified form of mandibulofacial dysostosis, a postaxial defect of the right, and a preaxial defect of the left hand. The Nager syndrome is characterized by preaxial limb defects, whereas the Genée-Wiedemann syndrome (= Miller syndrome) by postaxial limb defects. We briefly review the established acrofacial dysostoses (AFD) and discuss the position of our case in the current classification.

Using longitudinal roentgencephalometry, we studied craniofacial growth in two children with mandibulofacial dysostosis. In one child, data were supplemented by three-dimensional reconstructions of CT scans and stereolithographic models of the craniofacial skeleton. Progressive basilar kyphosis was found in both children, the hypothesized caused being bending of the cranial base at the level of the sphenofrontal suture. Such bending acting in concert with abnormal growth of the mandible led to impairment of the airway. We advocate careful monitoring of craniofacial growth and respiratory function in mandibulofacial dysostosis from birth through adolescence.

Acute exposure to 400 mg/kg 13-cis retinoic acid (13-cis RA, isotretinoin, Accutane) on the ninth day postfertilization in mice (a time that corresponds to the fourth week postfertilization in humans) results in malformations that characterize mandibulofacial dysostosis (MFD, Treacher Collins syndrome). Deficiencies in the infraorbital region and in the mandibular ramus and condyle, abnormalities of the secondary palate, and external ear malformations were observed. Light and scanning electron microscopic analyses of affected embryos illustrate that within 12 hours of maternal 13-cis RA treatment, markedly excessive (possibly premature) cell death occurs in regions where some of the cells are normally destined to undergo programmed cell death. Previous studies with retinoids have shown that they labilize lysosomal membranes and expand and strengthen regions of programmed cell death. Of particular interest for this study was cell death occurring in the dorsal (proximal) aspects of the maxillary and mandibular prominences of the first visceral arch, the second visceral arch, and the first visceral cleft, areas that correspond to the locations of the first and second arch ectodermal ("ganglionic") placodes and first closing membrane, respectively. The derivatives of this region are those that are severely affected in MFD. As described in previous reports from this laboratory, 13-cis RA is known to interfere with neural crest cells, resulting in major craniofacial malformations. However, the exposure times involved were earlier than those described herein. It is hypothesized that effects on the first and second arch ectodermal placodal cells at a time following the release from the neural folds of neural crest cells into the developing cranial region are of great significance in the pathogenesis of MFD. This is in contrast to the prevailing hypothesis that these malformations are the direct result of a primary interference with neural crest cells.

A review of the anatomical changes in patients with various "first arch" syndromes shows that some anomalies (e.g., micrognathia, ear defects) generally appear together. This study tested the hypothesis that the mandible, zygomatic arch, and middle ear ossicles are a developmental field (i.e., when any of these structures is anomalous, the other two will be also). The hypothesis was tested using data from 25 patients with mandibulofacial dysostosis (MFD) and 40 patients with hemifacial microsomia (HFM). Analysis of the pooled data showed that the hypothesis of character association was generally supported. However, the medians suggested that different factors probably played a role in determining how these three anatomical structures were associated in MFD and HFM. Errors in chondrogenesis may have been primarily responsible for the HFM phenotype. Alterations in Meckel and palatoquadrate cartilages would account for the size and shape changes observed in the ossicles and mandible, while changes in cranial base cartilages may explain the changes noted in the zygomatic arch. Since all three structures were equally affected in MFD, it is problematic to use an interference with chondrogenesis as an explanation for the phenotype. We conclude that although the mandible, zygomatic arch, and middle ear ossicles appear to form a "developmental field," the association between structures varies for HFM and MFD. The relatively lesser involvement of the zygomatic arch in HFM than in MFD suggests different pathogeneses for the two diagnostic groups and maybe a useful criterion for judging animal models of HFM.

Here we describe the phenotypic characteristics of a single craniofacial clinic population of 294 individuals affected with oculoauriculovertebral dysplasia (OAV) and variants. To our knowledge, this is the largest population so described in the literature. The study population was divided into five subgroups based on the presence of combinations of minimal diagnostic criteria: microtia, mandibular hypoplasia, anomalies of the cervical spine and/or epibulbar or lipodermoids. The following data were recorded: sex (M:F 191:103); race (78% Caucasian); the presence of unilateral or bilateral microtia (193 unilateral, 98 bilateral); the presence of symmetric microtia in bilateral cases (34/98); the presence of mandibular hypoplasia ipsilateral or contralateral to the microtic ear or most severely microtic ear in bilateral cases (135/137 were ipsilateral in unilateral cases, 55/62 were ipsilateral in bilateral cases); the number of individuals with no other congenital anomaly in addition to the minimal diagnostic criteria (154/294), with only one other congenital anomaly (51/294), and with two or more other congenital anomalies (89/294); and the type of other congenital anomalies. Finally, we compared our results with other studies. Findings from our study include: mandibular asymmetry should be expected in patients with unilateral or bilateral microtia; bilateral involvement is frequent in patients with microtia; other malformations are seen frequently in all subgroups; anomalies of the cervical spine are more likely to be associated with other anomalies; and other malformations are seen in all systems and should be searched for to provide optimal management.

Four patients are presented with the Goldenhar syndrome (GS) and cranial defects consisting of plagiocephaly, microcephaly, skull defects, or intracranial dermoid cysts. Twelve cases from the literature add hydrocephalus, encephalocele, and arhinencephaly to a growing list of brain anomalies in GS. As a group, these patients emphasize the variability of GS and the increased risk for developmental retardation with multiple, severe, or unusual manifestations. The temporal relation of proposed teratogenic events in GS provides an opportunity to reconstruct biological relationships within the 3-5-week human embryo.

In 1952, Goldenhar described a pair of monozygotic twins who were discordant for epibulbar dermoids, auricular appendages, malformations of the auricle, and hemifacial microsomia. Eighteen twin pairs have subsequently been described in which at least one member exhibited these manifestations. We report on an additional pair of discordant dichorionic monozygotic male twins. All of the 5 monozygotic twin pairs for which placental information is available have been discordant and 2 of these had dichorionic membranes. The failure of discordant monozygotic twins to be limited to monochorionic pairs argues against the hypothesis that developmental abnormalities arising from the placental vascular anastomoses that are commonly found in monozygotic twins is the probable explanation for the discordant expression of these traits in twins.