Syndrome-related outcomes following posterior vault distraction osteogenesis

Apert syndrome: neurosurgical outcomes and complications following posterior vault distraction osteogenesis

PURPOSE

Posterior vault distraction osteogenesis (PVDO) has been utilized during the past 15 years to treat a variety of clinical features commonly presented by patients with Apert syndrome. The objective of this study is to determine the efficacy of PVDO in addressing both elevated intracranial pressure (ICP) and ectopia of the cerebellar tonsils (ECT) in young Apert patients. In addition, we aimed to determine the prevalence of hydrocephalus in Apert syndrome patients who underwent PVDO.

METHODS

A retrospective study was made with a cohort of 40 consecutive patients with syndromic craniosynostosis (SC), previously diagnosed with Apert syndrome, who underwent PVDO between 2012 and 2022, and thereafter received at least 1 year of follow-up care. Demographic data and diagnosis, along with surgical and outcome data, were verified using medical records, clinical photographs, radiologic examination, and interviews with the parents of all cohort patients.

RESULTS

The average patient age when PVDO was performed was 12.91 ± 10 months. The average posterior advancement distance achieved per patient was 22.68 ± 5.26 mm. The average hospital stay per patient was 3.56 ± 2.44 days. The average absolute and relative blood transfusion volumes were 98.47 ml and 17.63 ml/kg, respectively. Although five patients (14%) presented ECT preoperatively, this condition was completely resolved by PVDO in three of these five patients. One of the three patients whose ECT had completely resolved presented syringomyelia postoperatively, requiring subsequent extra dural foramen magnum decompression. All of the remaining four patients were asymptomatic for ECT for at least 1 year of follow-up, and none of these four patients required any additional treatments to address ECT. Two patients presented hydrocephalus requiring ventriculoperitoneal shunt placement.

CONCLUSIONS

This study demonstrates that PVDO both reduces diagnosed elevated ICP symptoms and is partially effective in treating ECT in Apert syndrome patients. Hydrocephalus in Apert syndrome is an uncommon feature. The effectiveness of PVDO in addressing hydrocephalus is uncertain.

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.

Facial Fat Graft Injection Reduces Asymmetry and Improves Forehead Contour in Early Infancy Apert Syndrome Patients

BACKGROUND

The objective of this study is to report the outcomes of a modified comprehensive Apert syndrome surgical protocol in which fat injection was performed during early infancy concurrent with postposterior vault distraction osteogenesis (PVDO) distractor removal.

METHODS

A retrospective study was performed on 40 consecutive young patients with Apert syndrome who underwent PVDO and subsequent distractor removal between 2012 and 2022. Of these 40 patients, 12 patients underwent facial fat injection concurrent with distractor removal to treat residual supraorbital bar recession as part of a modified comprehensive Apert syndrome surgical protocol. Preoperative and postoperative severity of recession and irregularity was graded from 1 to 3, with 1 being less severe and 3 being the most severe. Recession severity was correlated with the number and type of suture fusion. The complication rate was stratified via a Clavien-Dindo scale.

RESULTS

The average patient age was 14.3±5 months, with 5 males (41.6%) and 7 females (48.3%). The average hospital stay was 1.08 days. The average volume of free fat graft injection was 8.29±5 mL. According to the Likert scale, forehead morphology improved in 91.67% of the patients. Complete resolution of supraorbital bar recession was achieved in seven patients (58.33%), all of whom presenting a single suture synostosis. One patient with a cloverleaf skull presented a type IIIB complication.

CONCLUSIONS

Facial fat grafting markedly reduces forehead asymmetry and improves forehead contour in Apert syndrome patients following PVDO. Total resolution of forehead recession directly correlated with a single suture fusion.

Apert Syndrome Type III Hand: Prevalence and Outcomes

BACKGROUND

The Upton type III hand, which represents the most severe hand type among Apert syndrome patients, has been considered the least prevalent hand type. The objective of this study is to address type III Apert hand prevalence and describe treatment strategies that will result in a 5 digit hand.

METHODS

The authors retrospectively reviewed 15 years of Apert syndrome hand practice at our hospital. Demographic (patient sex and age at the time of the operation), surgical (eg, techniques used for webspace release, osteotomy, and various aspects of soft-tissue reconstruction), and outcome (perioperative and long-term complication and need for revision operation) data was verified through medical records, clinical photographs, radiographic images, and interviews with patients' families. Patients who had incomplete medical records and/or postoperative follow up <6 months in length were excluded from this study.

RESULTS

A total of 93 Apert patients [50 male (56.1%) and 43 female (43.9%)] were treated at our hospital from 2007 to 2021. Stratification of Apert hand severity using Upton's classification system identified 34 patients with type I hands (36.4%), 19 patients with type II hands (20.6%), and 40 patients with type III hands (43%). Of the 40 patients with type III hands a 5 digit hand was achieved for 35 patients (87%), with an average of 3.37 operations per patient.

CONCLUSIONS

The Upton type III hand is the most prevalent hand type among Apert syndrome patients. Following a three stage protocol, a surgical team can consistently achieve a 5 digit hand for the majority of Apert syndrome patients with type III hands.

Apert Syndrome: Selection Rationale for Midface Advancement Technique

Apert syndrome is characterized by a wide spectrum of craniofacial clinical features that have been successfully addressed via a variety of midface advancement techniques. Although surgeons have individual preferences as to which specific procedures should be performed to best treat Apert patients, craniofacial plastic surgeons, working in tandem with pediatric neurosurgeons, can identify and evaluate functional limitations and facial morphologic disproportions, and establish appropriate criteria for effective midface advancement technique indication and selection. The purpose of this review article is to present and discuss our rationale for midface advancement technique selection based upon the most common craniofacial characteristics presented by Apert syndrome patients. The present article also provides a grading system that stratifies as major, moderate, and mild, the effect of each midface advancement technique on the different types of Apert syndrome facial features. Surgeons should take into consideration the maximum effect and benefit of each craniofacial osteotomy and how these procedures will alter the craniofacial skeleton. By understanding the long-term effect of each osteotomy on the most common craniofacial characteristics of Apert syndrome patients, craniofacial plastic surgeons and neurosurgeons will be able to customize the surgical procedures they perform in order to achieve the best possible outcomes.

Behavioral, Learning Skills, and Visual Improvement in Crouzon Syndrome Patient Following Late Posterior Vault Distraction Osteogenesis

BACKGROUND

It is well accepted among craniofacial surgeons that surgery does not improve mental status but does prevent worsening or deterioration of cognitive and mental function. In this report, we describe significant improvement in behavioral, learning skills and visual acuity for a Crouzon patient who underwent late posteriorvault distraction osteogenesis.

METHODS

A 9-year-old Crouzon patient was referred to our hospital, presenting severe intracranial hypertension. The patient had previously undergone a strip craniectomy in early infancy at another medical institution, but there was no subsequent follow-up. Magnetic resonance imaging showed Chiari type I malformation and fundoscopy revealed papilledema. At the time of referral, the patient was not attending a regular school, had not acquired reading skills, was unable to concentrate, and could not accomplish school-related tasks that were standard for children in his age group.

RESULTS

The patient underwent posterior vault distraction osteogenesis and showed concentration improvement and acquisition of fluent reading skills. Chiari type I malformation resolved as well as papilledema. visual acuity improved at Snellen test preoperatively from 20/200 to 20/60 at postoperative test. Ventricle size remained unchanged subsequent to performance of the posterior cranial vault distraction. The occipital veins were less visible upon clinical examination and less pronounced when palpated, and the bruit had completely disappeared.

CONCLUSION

Late posterior vault distraction osteogenesis can improve behavioral, learning skills and visual acuity as shown in this 9-year-old Crouzon patient.

Posterior Vault Distraction Outcomes in Patients with Severe Crouzon Syndrome Resulting from Ser347Cys and Ser354Cys Mutations

BACKGROUND

In this study, the authors present the outcomes of 4 patients with a severe form of Crouzon syndrome characterized by mutation of fibroblast growth factor receptor 2 (FGFR2) c.1040 C > G p.Ser347Cys or the pathogenic c.1061C > G p.Ser354Cys variant of FGFR2, who underwent posterior vault distraction osteogenesis (PVDO) to alleviate elevated intracranial pressure.

METHODS

Patients with diagnosed Crouzon syndrome who were found by genetic testing to have an FGFR2 c.1040 C > G p.Ser347Cys mutation or the c.1061C > G p.Ser354Cys variant were included. Outcome data and presence of hydrocephalus, Chiari Malformation type I (CMIs), and the presence/absence of a tracheostomy were recorded.

RESULTS

Three patients with the FGFR2 c.1040 C > G p.Ser347Cys mutation and 1 with the pathogenic FGFR2 c.1061C > G p.Ser354Cys variant were identified as having characteristics of severe Crouzon syndrome. The mean age at PVDO was 15 months and the mean posterior advancement was 20 mm. All 4 patients experienced sufficient relief of the elevated intracranial pressure from the PVDO to prevent the need for shunt placement, stabilize the ventricular dimensions (n = 2), and resolve the CMIs (n = 2). Intracranial pressure screening ruled out malignant cerebrospinal fluid volume increase.

CONCLUSIONS

PVDO effectively prevented hydrocephalus and resolved CMIs, successfully alleviating intracranial pressure and maximizing clinical outcomes for patients with severe Crouzon syndrome.