Saethre-Chotzen Syndrome: A Report of 7 Patients and Review of the Literature

Genetic Heterogeneity, Craniofacial Surgical Burden, and Surgical Techniques in Patients With Saethre-Chotzen Syndrome

OBJECTIVE

While genotype correlates with phenotype in patients with many forms of syndromic craniosynostosis, the relationship between molecular diagnosis and craniofacial surgical history in patients with Saethre-Chotzen syndrome (SCS) is more variable. This manuscript characterizes that relationship and evaluates operative trends in these patients over the past 3 decades.

METHODS

Demographic information, molecular diagnosis, and craniofacial surgical history in patients born with SCS between 1989 and 2023 were compared with appropriate statistics, including t tests and analysis of variance.

RESULTS

Thirty-five patients with SCS were included, and there was no difference in total craniofacial procedures among those with TWIST1 substitutions (2.1 ± 1.6), duplications (3.0 ± 4.2), insertions (3.5 ± 0.7), or deletions (2.4 ± 1.9; P = 0.97). Cranial expansion rates were also similar across all genetic diagnoses (P>0.05), and surgical incidence was similar across patients with unicoronal, bicoronal, and multisuture involvement (P > 0.05). Those with an initial fronto-orbital advancement had a lower incidence of secondary cranial vault procedures compared with those with an initial posterior vault distraction osteogenesis (29% versus 71%, P < 0.05), though this did not control for phenotypic severity. On average, total cranial vault surgical burden (1.35 ± 0.67 versus 1.75 ± 0.46) and cranial expansion surgical burden (1.40 ± 0.68 versus 1.88 ± 0.64) between the fronto-orbital advancement-first and posterior vault distraction osteogenesis-first cohorts were similar (P = 0.11, P = 0.17, respectively).

CONCLUSION

While SCS is molecularly and phenotypically heterogeneous, genetic diagnosis does not appear associated with rates of craniofacial surgery. Additional prospective study of correlations between genotype, severity of craniofacial manifestations, and treatment algorithms is warranted; but, in the end, it may be that this highly variable form of syndromic craniosynostosis warrants tailored, expectant management.

Patient Tailored Surgery in Saethre-Chotzen Syndrome: Analysis of Reoperation for Intracranial Hypertension

Saethre-Chotzen syndrome (SCS) is a syndromic craniosynostosis with pathogenic variants in the TWIST1 gene showing a broad phenotypic spectrum. Controversies exist in the literature regarding surgical management with single one-stage versus patient-tailored surgery and the related reoperation rate for intracranial hypertension of up to 42%. At our center, SCS patients are offered patient-tailored surgery with single-stage fronto-orbital advancement and remodeling or fronto-orbital advancement and remodeling and posterior distraction in an individually determined order. The authors' database identified 35 confirmed SCS patients between 1999 and 2022. Involved sutures in craniosynostosis were left unicoronal (22.9%), bicoronal (22.9%), sagittal (8.6%), bicoronal and sagittal (5.7%), right unicoronal (2.9%), bicoronal and metopic (2.9%), bicoronal, sagittal and metopic (2.9%), and bilateral lambdoid (2.9%). There was pansynostosis in 8.6% and no craniosynostosis in 14.3% of the patients. Twenty-six patients, 10 females, and 16 males were operated on. Mean age at the first surgery was 1.70 years, and 3.86 years at the second surgery. Eleven of 26 patients had invasive intracranial pressure monitoring. Three patients presented with papilledema before the first surgery and 4 afterward. Four of the 26 operated patients were operated initially elsewhere. The other 22 patients were initially referred to our unit and underwent patient-tailored surgery. Nine of these patients (41%) had a second surgery, and 3 (14%) of them were because of raised intracranial pressure. Seven (27%) of all operated patients had a complication. Median follow-up was 13.98 years (range, 1.85-18.08). Patient-tailored surgery in a specialized center and long-term follow-up allow for a low reoperation rate for intracranial hypertension.

Diagnosis, treatment, and research status of rare diseases related to birth defects

Rare diseases are diseases that occur at low prevalence, and most of them are chronic and serious diseases that are often life-threatening. Currently, there is no unified definition for rare diseases. The diagnosis, treatment, and research of rare diseases have become the focus of medicine and biopharmacology, as well as the breakthrough point of clinical and basic research. Birth defects are the hard-hit area of rare diseases and the frontiers of its research. Since most of these defects have a genetic basis, early screening and diagnosis have important scientific value and social significance for the prevention and control of such diseases. At present, there is no effective treatment for most rare diseases, but progress in prenatal diagnosis and screening can prevent the occurrence of diseases and help prevent and treat rare diseases. This article discusses the progress in genetic-related birth defects and rare diseases.

Postnatal Progressive Craniosynostosis in Syndromic Conditions: Two Patients With Saethre-Chotzen Due to TWIST1 Gene Deletions and Review of the Literature

Saethre-Chotzen syndrome (SCS) is a known craniosynostosis syndrome with a variable presentation of craniofacial and somatic involvement. Congenital coronal craniosynostosis is most commonly observed in SCS; however, progressive postnatal craniosynostosis of other sutures has been reported. The authors present 2 infants with progressive postnatal craniosynostosis and SCS caused by chromosome 7p deletions including the TWIST1 gene. The evolution of their clinical features and a literature review of patients with syndromic, postnatal progressive craniosynostosis illustrate the importance of longitudinal observation and management of these patients.