Concordant contralateral lambdoidal synostosis in dizygotic twins

Management of Lambdoid Craniosynostosis: A Comprehensive and Systematic Review

BACKGROUND

Craniosynostosis is a condition characterized by the premature fusion of 2 or more skull bones. Craniosynostosis of the lambdoid suture is one of the rarest forms, accounting for 1-4% of all craniosynostoses. Documented cases are separated into simple (single suture), complex (bilateral), and associated with adjacent synostoses ("Mercedes Benz" Pattern) or syndromes (i.e., Crouzon, Sathre-Chotzen, Antley-Bixler). This condition can manifest phenotypic deformities and neurological sequelae that can lead to impaired cognitive function if improperly treated or left undiagnosed. Preferred surgical techniques have varied over time but all maintain the common goals of establishing proper head shape and preventing of complications that could contribute to aforementioned sequelae.

SUMMARY

This comprehensive review highlights demographic distributions, embryological development, pathogenesis, clinical presentation, neurological sequelae, radiologic findings, surgical techniques, surgical outcomes, and postoperative considerations of patients with lambdoid craniosynostosis presentation. In addition, a systematic review was conducted to explore the operative management of lambdoid craniosynostosis using PubMed, Embase, and Scopus databases, with 38 articles included after screening. Key Messages: Due to a low volume of published cases, diagnosis and treatment can vary. Large overlap in presentation can occur in patients that display lambdoid craniosynostosis and posterior plagiocephaly, furthering the need for comprehensive analysis. Possessing the knowledge and tools to properly assess patients with lambdoid craniosynostosis will allow for more precise care and improved outcomes.

The Etiology of Neuronal Development in Craniosynostosis: A Working Hypothesis

Craniosynostosis is one of the most common craniofacial conditions treated by neurologic and plastic surgeons. In addition to disfigurement, children with craniosynostosis experience significant cognitive dysfunction later in life. Surgery is performed in infancy to correct skull deformity; however, the field is at a crossroads regarding the best approach for correction. Since the cause of brain dysfunction in these patients has remained uncertain, the role and type of surgery might have in attenuating the later-observed cognitive deficits through impact on the brain has been unclear. Recently, however, advances in imaging such as event-related potentials, diffusion tensor imaging, and functional MRI, in conjunction with more robust clinical studies, are providing important insight into the potential etiologies of brain dysfunction in syndromic and nonsyndromic craniosynostosis patients. This review aims to outline the cause(s) of such brain dysfunction including the role extrinsic vault constriction might have on brain development and the current evidence for an intrinsic modular developmental error in brain development. Illuminating the cause of brain dysfunction will identify the role of surgery can play in improving observed functional deficits and thus direct optimal primary and adjuvant treatment.

Lambdoidal synostosis in dizygotic twins with a family history of an undiagnosed connective tissue disorder

INTRODUCTION

Unilateral lambdoidal craniosynostosis is a rare disorder that occurs in approximately 3 % of all craniosynostosis phenotypes and only 0.03 % of one million live births. It is even more unusual for this type of synostosis to occur in siblings with only two other cases reported in the literature.

CASE REPORT

We report a set of full-term dizygotic twins born with lambdoidal synostosis and a family history of connective tissue and cardiovascular anomalies. One of the twins also had concomitant bicoronal craniosynostosis.

CONCLUSION

True familial lambdoidal synostosis is exceedingly rare. The present cases in dizygotic twins occurred in a family with a significant history of connective tissue disease suggesting a possible association.

Genetic basis of single-suture synostoses: genes, chromosomes and clinical implications

BACKGROUND

Non syndromic craniosynostoses are the most frequent craniofacial malformations worldwide. They represent a wide and heterogeneous group of entities, in which the dysmorphism may occur in a single (simple forms) or in multiple sutures (complex forms). Simple forms present a higher birth prevalence and are classified according to the involved suture and to the corresponding abnormal cranial shape: scaphocephaly (SC; sagittal suture), trigonocephaly (TC; metopic suture), anterior plagiocephaly (unilateral coronal suture), posterior plagiocephaly (unilateral lambdoid suture). They occur commonly as sporadic forms, although a familiar recurrence is sometimes observed, suggesting a mendelian inheritance. The genetic causes of simple craniosynostosis are still largely unknown, as mutations in common craniosynostosis-associated genes and structural chromosomal aberrations have been rarely found in these cases.

AIMS

This review is intended to dissect comprehensively the state-of-the art on the genetic etiology of single suture craniosynostoses, in the attempt to categorize all known disease-associated genes and chromosomal aberrations. Possible genotype/phenotype correlations are discussed as useful clues towards the definition of optimized clinical management flowcharts.

Familial lambdoid craniosynostosis between father and son

Lambdoid craniosynostosis is an uncommon condition, with an incidence of 1 per 33,000 live births. Its etiopathology remains controversial. Although many forms of syndromic and nonsyndromic craniosynostosis demonstrate an inherited pattern, few articles have reported lambdoid craniosynostosis in the same family. In this article, we report lambdoid synostosis in a father and son. A case review is performed. A full-term male infant was delivered by cesarean delivery because of failure to progress. He presented at 3 years of age with right unilateral lambdoid craniosynostosis with facial asymmetry and lateral deviation of his jaw, with occlusal abnormality. At presentation, the father reported skull surgery during his infancy for unilateral lambdoid craniosynostosis. Review of the computed tomographic scan of the child demonstrated a plagiocephalic appearance of the calvarium with frontal bossing and a fusion of the lambdoid suture on the right sides. The brain parenchyma showed no abnormality. The review of his father's surgical record from 33 years ago and of his computed tomographic scan ordered by our team confirmed the diagnosis of previous lambdoid craniosynostosis. Only 2 previous cases of familial isolated lambdoid craniosynostosis have been previously described in literature. Although the genetic basis has been established for many types of craniosynostosis, the etiopathogenesis of isolated lambdoid synostosis has not yet been established. We report the third case of inherited unilateral lambdoid craniosynostosis. The genetic pathogenesis of lambdoid craniosynostosis will be discussed.