Genetic Evaluation for Craniofacial Conditions

Frequency and Management of Craniofacial Syndromes

BACKGROUND

Craniofacial syndromes occur in approximately 1 in 5600 to 100,000 infants, often resulting in significant morbidity. Due to the heterogeneity of this patient population, no clear consensus consists on optimal treatment modalities and timing. The aim of this study was to analyze the craniofacial syndrome population that were treated at the University Hospital Leuven.

METHODS

A retrospective analysis of patients with a clinical diagnosis of a craniofacial syndrome was performed. Inclusion criteria were patients with a clinical diagnosis of a craniofacial syndrome and that received treatment between "2000-2005" and "2010-2015." Patients with nonsyndromic conditions were excluded. Data regarding patient characteristics, treatment modalities, and treatment outcomes were analyzed.

RESULTS

After matching the inclusion criteria, 98 eligible patients, affected by 40 different syndromes were included. In the period of "2000 to 2005," 48 patients were treated, as compared to 50 patients in the period of "2010 to 2015." A statistically significant decrease over time is seen for cleft surgery and orthodontic treatment (P = 0.0017 and P = 0.0015, respectively). No statistically significant differences were found concerning the age at which treatment was received (P = 0.42). Significant associations between treatment modalities were found for orthognathic surgery and distraction osteogenesis (P < 0.0001), orthognathic surgery and orthodontic treatment (P < 0.0001), and between orthodontic treatment and distraction osteogenesis (P = 0.03311).

CONCLUSION

A decline in cleft reconstruction surgery and orthodontic treatment for patients with craniofacial syndromes was seen over time. A significant association was found between distraction osteogenesis and orthognathic surgery, possibly due to higher reintervention rates for patients treated at a young age.

Craniosynostosis - Recognition, clinical characteristics, and treatment

Craniosynostosis is a developmental craniofacial anomaly, resulting in impairment of brain development and abnormally shaped skull. The main cause of craniosynostosis is premature closure of one or more cranial sutures. It usually occurs as an isolated condition, but may also be associated with other malformations as part of complex syndromes. When left untreated, craniosynostosis can cause serious complications, such as developmental delay, facial abnormality, sensory, respiratory and neurological dysfunction, anomalies affecting the eye, and psychological disturbances. Thus, early diagnosis, expert surgical techniques, postoperative care, and adequate follow-up are of vital importance in treating craniosynostosis.

Craniofacial disorders

The complexity of the craniofacial patient mandates the cooperation of a multidisciplinary team that can systematically evaluate each individual and ensure that a protocol-driven pathway is undertaken for the best patient care. Oral and maxillofacial surgeons contribute to surgical care in this setting with specific knowledge of growth and development of the face. This enables optimum timing for early skeletal correction where appropriate, and definitive surgery following the cessation of growth to maximize function and aesthetics. This chapter will describe the major principles in managing patients with specific craniofacial anomalies and provide examples of the outcomes possible.

Mouth development

A mouth is present in all animals, and comprises an opening from the outside into the oral cavity and the beginnings of the digestive tract to allow eating. This review focuses on the earliest steps in mouth formation. In the first half, we conclude that the mouth arose once during evolution. In all animals, the mouth forms from ectoderm and endoderm. A direct association of oral ectoderm and digestive endoderm is present even in triploblastic animals, and in chordates, this region is known as the extreme anterior domain (EAD). Further support for a single origin of the mouth is a conserved set of genes that form a 'mouth gene program' including foxA and otx2. In the second half of this review, we discuss steps involved in vertebrate mouth formation, using the frog Xenopus as a model. The vertebrate mouth derives from oral ectoderm from the anterior neural ridge, pharyngeal endoderm and cranial neural crest (NC). Vertebrates form a mouth by breaking through the body covering in a precise sequence including specification of EAD ectoderm and endoderm as well as NC, formation of a 'pre-mouth array,' basement membrane dissolution, stomodeum formation, and buccopharyngeal membrane perforation. In Xenopus, the EAD is also a craniofacial organizer that guides NC, while reciprocally, the NC signals to the EAD to elicit its morphogenesis into a pre-mouth array. Human mouth anomalies are prevalent and are affected by genetic and environmental factors, with understanding guided in part by use of animal models. WIREs Dev Biol 2017, 6:e275. doi: 10.1002/wdev.275 For further resources related to this article, please visit the WIREs website.