Apert Syndrome Outcomes: Comparison of Posterior Vault Distraction Osteogenesis Versus Fronto Orbital Advancement

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.

Posterior Cranial Distraction in Craniosynostosis: A Systematic Review of the Literature

OBJECTIVE

Posterior cranial distraction (PCD) is a surgical technique to address craniosynostosis, especially in syndromic patients. The technique has the ability to significantly expand the cranium, while requiring minimal dural dissection, compared to cranial remodeling. Our goals were to determine the patient characteristics and surgical outcomes of PCD. The two questions that we sought to answer were: 1) What is the average published complication rate and the most common complications of PCD? and 2) How much intracranial volume expansion can one expect with PCD?

DESIGN

A PubMed database search of articles on PCD was performed. Case reports and articles with overlapping patients were excluded. A systematic review was performed using the remaining articles.

MAIN OUTCOME MEASURES

Patient data were extracted in order to determine the total number of patients, patients with a syndrome, types of syndromes, mean age at surgery, mean distraction distance, mean increase in intracranial volume, and complications.

RESULTS

18 articles representing 325 patients were analyzed. A syndrome was present in 68.6% of patients. The mean age at time of surgery was 22.1 months. Mean distraction amount was 24.7 mm. Mean increase in intracranial volume was 253.2 cm3. The overall complication rate was 32.2%, with the most common complications being surgical-site infection, hardware-related complications and delayed wound healing.

CONCLUSIONS

PCD is a powerful technique in the management of syndromic craniosynostosis, although complication rates are significantly higher than traditional remodeling techniques. Future studies should compare the effects of supratorcular and infratorcular osteotomies on intracranial volume, cosmesis and complications.

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.

Perioperative Morbidity of Secondary Frontal Orbital Advancement After Initial Frontal Orbital Advancement

Frontal orbital advancement (FOA) is frequently performed for patients with syndromic and/or multisuture craniosynostosis. A small proportion of patients who undergo FOA have unfavorable growth and subsequently require a second FOA later in life; however, the perioperative risks associated with this second procedure are not well studied. We report results from a retrospective review of FOAs conducted from 2007 to 2022 at a single site with the same craniofacial surgeon. A total of 33 patients were included. Perioperative outcomes were compared between primary and secondary FOA procedures. The two groups were similar in regard to suture involvement and diagnosis, although the secondary FOA group was older at the time of their FOA (1.23 versus 7.07 y, P <0.001). There was no significant difference between groups in operating time, volume of blood transfusion by weight, or in the incidence of postoperative wound complications ( P >0.05). Primary FOA procedures had significantly higher weight-adjusted blood loss (28 versus 18 mL/kg, P =0.014), with a higher proportion of patients receiving a blood transfusion (95% versus 62%, P =0.025). There was no significant difference between groups in the incidence of intraoperative dural injury (50% versus 84%, P =0.067). Our findings suggest that secondary procedures appear to impose less of a surgical risk relative to primary FOA traditionally performed in infancy, likely because of the advanced age at the time of secondary FOA.

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.