Correcting the Typical Apert Face: Combining Bipartition with Monobloc Distraction

Apert syndrome: craniofacial challenges and clinical implications

Apert syndrome is a rare acro-cephalo-syndactyly syndrome characterised by craniosynostosis, severe syndactyly of hands and feet, and dysmorphic facial features. It demonstrates autosomal dominant inheritance assigned to mutations in the fibroblast growth factor receptor gene, as a result of which signals are not received to produce necessary fibrous material necessary for normal cranial sutures. Deformities are generally cosmetic but can affect various functions such as hearing, visual abnormalities, swallowing, writing, etc, so a multidisciplinary approach is needed for their management.Presently described is a case of a male in his late adolescence who was medically diagnosed with Apert syndrome at birth. Physical appearance and dental examination of the patient included acrocephaly, prominent forehead, ocular hypertelorism, proptosis, short and broad nose, pseudo-prognathism, dental crowding and ectopia, maxillary hypoplasia, low hairline, webbed neck, pectus excavatum and severe bilateral syndactyly of hands and feet.

Isolated hypertelorism: Late surgical correction using the box osteotomy technique

Background

Orbital hypertelorism is a rare congenital condition caused by craniofacial malformations. It consists of complete orbital lateralization, characterized by an increase in distance (above the 95th percentile) of the inner canthal (ICD), outer canthal, and interpupillary distances. It can be approached surgically, and the main techniques are box osteotomy and facial bipartition. The surgical procedure is usually performed before the age of 8. We describe here two patients who underwent late surgical correction using the box osteotomy technique.

Case Description

Patient 1: A 13-year-old female presenting isolated hypertelorism with 5 cm ICD and left eye amblyopia. Patient 2: A 15-year-old female with orbital hypertelorism, 4.6 cm ICD, and nasal deformity. Both patients underwent orbital translocation surgery and had no neurological disorders.

Conclusion

The article reports two cases of isolated hypertelorism treated late with the box osteotomy technique. Both surgeries were successful, with no postoperative complications. It appears that it is possible to obtain good surgical results even in patients who have not been able to undergo surgery previously.

LeFort III Versus Monobloc Frontofacial Advancement: A Comparative Analysis of Soft Tissue Changes

INTRODUCTION

The LeFort III and monobloc are commonly used midface advancement procedures for patients with syndromic craniosynostosis with well characterized postoperative skeletal changes. However, the differential effects of these procedures on facial soft tissues are less understood. The purpose of this study was to critically analyze and compare the effects of these 2 procedures on the overlying soft tissues of the face.

METHODS

Frontal and lateral preoperative and postoperative photographs of patients undergoing monobloc or LeFort III were retrospectively analyzed using ImageJ to measure soft tissue landmarks. Measurements included height of facial thirds, nasal length and width, intercanthal distance, and palpebral fissure height and width. Facial convexity was quantified by calculating the angle between sellion (radix), subnasale, and pogonion on lateral photographs.

RESULTS

Twenty-five patients with an average age of 6.7 years (range 4.8-14.5) undergoing monobloc (n=12) and LeFort III (n=13) were identified retrospectively and analyzed preoperatively and 6.4±3.6 months postoperatively. Patients undergoing LeFort III had a greater average postoperative increase in facial convexity angle acuity (28.2°) than patients undergoing monobloc (17.8°, P =0.021). Patients in both groups experience postoperative increases in nasal width ( P <0.001) and decreases in palpebral fissure height ( P <0.001).

CONCLUSIONS

Both subcranial LeFort III advancements and monobloc frontofacial advancements resulted in significant changes in the soft tissues. Patients undergoing LeFort III procedures achieved greater acuity of the facial convexity angle, likely because the nasion is not advanced with the LeFort III segment.

Effect of Midface Surgery on Ocular Outcomes in Patients with Orbital and Midface Malformations

(1) Background: Orbital and midface malformations occur in multiple craniofacial disorders. Depending on the deformity, surgical corrections include orbital box osteotomy (OBO), Le Fort III (LFIII), monobloc (MB), and facial bipartition (FB). The aim of this study was to determine the effect of these procedures on ocular outcomes. (2) Methods: A retrospective analysis was performed. All patients with craniofacial disorders who had previously undergone midface surgery were included. The Wilcoxon signed ranks test was used for statistical analysis. (3) Results: In total, 63 patients were included: two patients were treated by OBO, 20 by LFIII, 26 by MB, and 15 by FB. Pre-operatively, strabismus was present in 39 patients (61.9%), in whom exotropia was most common (n = 27; 42.9%), followed by esotropia (n = 11; 17.5%). Postoperatively, strabismus significantly worsened (p = 0.035) in the overall population (n = 63). Pre-operative binocular vision (n = 33) was absent in nine patients (27.3%), poor in eight (24.2%), moderate in 15 (45.5%), and good in one (3.0%). Postoperatively, binocular vision significantly improved (p < 0.001). Before surgery, the mean visual acuity (VA) in the better eye was 0.16 LogMAR (Logarithm of the Minimum Angle of Resolution), and 0.31 LogMAR in the worse eye. Furthermore, pre-operative astigmatism was present in 46 patients (73.0%) and hypermetropia in 37 patients (58.7%). No statistical difference was found for VA (n = 51; p = 0.058) postoperatively. (4) Conclusions: Midface surgery has a direct and indirect substantial effect on several ocular outcomes. This study emphasizes the importance of appropriate ophthalmological evaluation in patients with craniofacial disorders undergoing midface surgery.

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.

Syndromic Synostosis: Frontofacial Surgery

Frontofacial surgery, encompassing the monobloc with or without facial bipartition and the box osteotomy, can treat the frontal bone and midface simultaneously, providing comprehensive improvement in facial balance. Complex pediatric patients with genetic syndromes and craniosynostosis are most optimized by an interdisciplinary team of surgeons, pediatricians, geneticists, speech pathologists, audiologists, dietitians, pediatric dentists, orthodontists, and psychosocial support staff to manage the myriad of challenges and complications throughout early childhood and beyond. Despite early treatment of the anterior and posterior cranial vault, these patients frequently have resultant frontal and/or midface hypoplasia and orbital abnormalities that are best managed with simultaneous surgical treatment.

Prevalence of Ocular Anomalies in Craniosynostosis: A Systematic Review and Meta-Analysis

Background: The aim of this study was to describe the ophthalmic abnormalities and their prevalence in craniosynostosis prior to craniofacial surgery. Methods: A systematic search was conducted on Medline OVID, Embase, Cochrane, Google Scholar, Web of Science Core Collection. Inclusion criteria were English papers, children aged <18 years with non-syndromic and syndromic craniosynostosis, case reports, case series, and case-control studies. A system of domains was established consisting of an anatomic and functional ophthalmic domain. A meta-analysis of single proportions was carried out using random effects model and pooled mean proportions with 95% confidence intervals (CI) were calculated. Results: Thirty-two papers analyzing 2027 patients were included. Strabismus was the most common anomaly in non-syndromic craniosynostosis: Horizontal strabismus was highest prevalent in unicoronal craniosynostosis (UCS) 19% (95% CI 9–32), followed by vertical strabismus 17% (95% CI 5–33). In syndromic craniosynostosis, horizontal strabismus was most prevalent in Crouzon syndrome 52% (95 CI 26–76), followed by Apert syndrome 50% (95% CI 42–58). Vertical strabismus was most prevalent in Saethre-Chotzen 60% followed by Muenke’s syndrome 36%. Furthermore, astigmatism was the second most reported outcome in non-syndromic craniosynostosis and highest prevalent in UCS 35% (95% CI 21–51). In syndromic craniosynostosis, astigmatism was most frequently seen in Crouzon syndrome 43% (95% CI 22–65), followed by Apert syndrome 34% (95% CI 14–58). Moreover, in syndromic craniosynostosis, 5–40% had a decrease in visual acuity (VA) ≤ 0.3 LogMAR in the better eye and 11–65% had a VA ≤ 0.3 LogMAR in at least one eye. Discussion: This review demonstrates the high prevalence of ocular anomalies in non-syndromic and syndromic craniosynostosis. A multidisciplinary and systematic approach is needed for the screening and optimal treatment of these conditions in a timely manner.

Orbital and Periorbital Dysmorphology in Untreated Pfeiffer Syndrome

BACKGROUND

Visual impairment secondary to orbital and periorbital dysmorphology is frequent in Pfeiffer syndrome patients. The etiopathogenesis of this aberrancy, however, remains unclear.

METHODS

Untreated Pfeiffer syndrome patients (n = 31) and normal control subjects (n = 43) were compared. Craniometric and volumetric analyses related to the orbital and periorbital anatomy were performed using Materialise (Leuven, Belgium) software.

RESULTS

Overall, orbital cavity volume of Pfeiffer patients is reduced by 28 percent (p < 0.001), compared to normal, starting before 3 months of age (p = 0.004). Globe volume was diminished by 10 percent (p = 0.041) before 3 months of age, yet tended to catch up thereafter. However, the retrobulbar soft-tissue volume remained smaller beyond 1 year of age (17 percent, p = 0.003). Globe volume projection beyond the bony orbit increased in all observed ages (82 percent, p < 0.001). The volumes of sphenoid bone, maxilla, and mandible proportionately were restricted by 24 to 25 percent (p = 0.003 to 0.035) before 3 months of age. The volume of maxilla and mandible gradually approximate normal; however, the sphenoid bone volume in Pfeiffer patients remains less than normal (p = 0.002) into childhood. The anteroposterior length of both the zygoma and the maxilla was reduced by 14 percent (p < 0.001). Anterior positioning of the zygoma is less by 23 percent (p < 0.001) in Pfeiffer patients overall, with anterior positioning of maxilla reduced similarly by 23 percent (p < 0.001).

CONCLUSIONS

Pfeiffer syndrome patients develop decreased retrobulbar soft-tissue and globe volume, along with a restricted orbital cavity volume in infancy. Significant hypoplasia of the sphenoid bone is associated with more severe central facial (maxilla) retrusion, compared to lateral facial structures (zygoma).

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Maxillary Changes Following Facial Bipartition - A Three-Dimensional Quantification

INTRODUCTION

Children with Apert syndrome have hypertelorism and midfacial hypoplasia, which can be treated with facial bipartition (FB), often aided by rigid external distraction. The technique involves a midline osteotomy that lateralizes the maxillary segments, resulting in posterior cross-bites and midline diastema. Varying degrees of spontaneous realignment of the dental arches occurs postoperatively. This study aims to quantify these movements and assess whether they occur as part of a wider skeletal relapse or as dental compensation.

METHODS

Patients who underwent FB and had high quality computed tomography scans at the preoperative stage, immediately postsurgery, and later postoperatively were reviewed. DICOM files were converted to three-dimensional bone meshes and anatomical point-to-point displacements were quantified using nonrigid iterative closest point registration. Displacements were visualized using arrow maps, thereby providing an overview of the movements of the facial skeleton and dentition.

RESULTS

Five patients with Apert syndrome were included. In all cases, the arrow maps demonstrated initial significant anterior movement of the frontofacial segment coupled with medial rotation of the orbits and transverse divergence of the maxillary arches. The bony position following initial surgery was shown to be largely stable, with primary dentoalveolar relapse correcting the dental alignment.

CONCLUSIONS

This study showed that spontaneous dental compensation occurs following FB without compromising the surgical result. It may be appropriate to delay active orthodontic for 6-months postoperatively until completion of this early compensatory phase.

Does different cranial suture synostosis influence orbit volume and morphology in Apert syndrome?

This study was performed to compare the orbital and peri-orbital morphological variations in Apert syndrome patients with different cranial vault suture synostosis, so as to provide an anatomic basis for individualized surgical planning. Computed tomography scans of 57 unoperated Apert syndrome patients and 59 controls were subgrouped as follows: type I, bilateral coronal synostosis; type II, pansynostosis; type III, perpendicular combinations of cranial vault suture synostoses. Orbit bony cavity volume was significantly reduced in type I and type II, by 19% (P < 0.001) and 24% (P < 0.001), respectively. However, the reduction of orbital cavity volume in type III did not reach statistical significance. Globe volume projection beyond the orbital rim, however, increased by 76% (P < 0.001) in type III, versus an increase of 54% (P < 0.001) in type I and 53% (P < 0.001) in type II, due to different ethmoid and sphenoid bone malformations. Maxillary bone volume was only significantly reduced in type I bicoronal synostosis (by 24%, P = 0.048). Both type I and type II developed relatively less zygoma and sphenoid bone volume. Different cranial vault suture synostoses have varied influence on peri-orbital development in Apert syndrome. Instead of mitigating the abnormalities resulting from bicoronal synostosis in type I, additional midline suture synostosis worsens the exorbitism due to a more misshaped ethmoid.

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

BACKGROUND

Presenting a wide clinical spectrum and large variety of clinical features, successful treatment of Apert syndrome necessitates performance of sequential multiple surgeries before a patient's facial skeleton growth is complete.The objective of this study is to compare forehead contour asymmetry and clinical outcomes between Apert patients who underwent either fronto-orbital advancement (FOA) or posterior vault distraction osteogenesis (PVDO).

METHODS

A retrospective study was performed on consecutive patients with Apert syndrome who underwent either FOA or PVDO between 2007 and 2019, and participated in at least 6 months of follow-up care. Forehead contour asymmetry and surgical outcomes for each of the included patients were verified through medical records, clinical photographs, and interviews with the parents of the patients. The need for additional craniofacial procedures based on the surgical outcomes of each patient was graded from I to IV utilizing the Whitaker outcome classification system.

RESULTS

Forehead contour asymmetry for all included patients was rated under the Whitaker grading scale as type II (n = 4) 44.4%, type III (n = 2) 22.2%, and type IV (n = 3) 33.3% for FOA, and type I (n = 5) 35.7%, type II (n = 7) 50%, and type III (n = 2) 14.3%, for PVDO (P < 0.05). The average transfused blood volume was 47.77 ± 9.42 mL/kg for patients who underwent FOA, and 22.75 ± 10.31 mL/kg for patients who underwent PVDO (P < 0.05).

CONCLUSIONS

Patients who underwent PVDO had lower forehead contour asymmetry as per the Whitaker outcome grading scale than patients who underwent FOA.

Local Soft Tissue and Bone Displacements Following Midfacial Bipartition Distraction in Apert Syndrome - Quantification Using a Semi-Automated Method

ABSTRACT

Patients with Apert syndrome experience midfacial hypoplasia, hypertelorism, and downslanting palpebral fissures which can be corrected by midfacial bipartition distraction with rigid external distraction device. Quantitative studies typically focus on quantifying rigid advancement and rotation postdistraction, but intrinsic shape changes of bone and soft tissue remain unknown. This study presents a method to quantify these changes. Pre- and post-operative computed tomography scans from patients with Apert syndrome undergoing midfacial bipartition distraction with rigid external distraction device were collected. Digital Imaging and Communications in Medicine files were converted to three-dimensional bone and soft tissue reconstructions. Postoperative reconstructions were aligned on the preoperative maxilla, followed by nonrigid iterative closest point transformation to determine local shape changes. Anatomical point-to-point displacements were calculated and visualized using a heatmap and arrow map. Nine patients were included.Zygomatic arches and frontal bone demonstrated the largest changes. Mid-lateral to supra-orbital rim showed an upward, inward motion. Mean bone displacements ranged from 3.3 to 12.8 mm. Soft tissue displacements were relatively smaller, with greatest changes at the lateral canthi. Midfacial bipartition distraction with rigid external distraction device results in upward, inward rotation of the orbits, upward rotation of the zygomatic arch, and relative posterior motion of the frontal bone. Local movements were successfully quantified using a novel method, which can be applied to other surgical techniques/syndromes.

Treating Syndromic Craniosynostosis with Monobloc Facial Bipartition and Internal Distractor Devices: Destigmatizing the Syndromic Face

Monobloc and facial bipartition combined with distraction osteogenesis (MFBDO) has gained popularity over the past several years as a treatment of syndromic craniosynostosis, in part because this surgical technique effectively removes many stigmatic clinical features associated with the syndromic face. The objective of this study is to detail the surgical planning used to achieve medialization of the orbits and describe the authors' experience using MFBDO to destigmatize the syndromic face. By using MFBDO, hypertelorism, vertical orbital dystopia, and downslanting of the palpebral fissure were surgically corrected in all patients, thereby destigmatizing the syndromic face.

Lefort II distraction with zygomatic repositioning versus Lefort III distraction: A comparison of surgical outcomes and complications

The aim of the study was to determine if the additional surgical complexity of Lefort II distraction with zygomatic repositioning (LF2ZR) results in increased complications compared to Lefort III distraction (LF3). A retrospective review was performed of all LF3 and LF2ZR advancements performed by the senior author over 15 years. Demographic, operative, postoperative, and cephalometric data were collected from initial procedure through greater than 1 year postoperatively. Univariate and multivariate analyses were performed to compare procedures. 19 LF2ZR and 39 LF3 in 53 patients met inclusion criteria. Diagnoses differed between procedures, with more Crouzon Syndrome in LF3 and more Apert Syndrome in LF2ZR. Complication rate was 7/19 for LF2ZR and 12/39 for LF3 with no severe morbidity or mortality, and no difference between procedures (p = 0.56). The types of complications encountered differed between procedures. LF2ZR had a significantly longer operative time (506 ± 18 vs. 358 ± 24 min, p<0.001). However, a greater number of LF2ZR patients underwent concomitant procedures (15/19 vs. 13/39, p<0.001). Multivariate analysis revealed that Apert Syndrome and reoperative midface advancement were the most significant predictors of increased blood loss. LF2ZR has an equivalent complication rate to LF3. Therefore, it is our treatment of choice for cases requiring differential sagittal and vertical distraction of the central midface.

Le fort II distraction osteogenesis with a hybrid system for an Apert syndrome patient: A case report

Background

Le Fort II advancement is considered for normalizing the facial appearance in Apert syndrome. When these procedures are performed during growth, overcorrection of midface advancement is required. We developed a system that can control the distance and vector of movement for the central midface to create more normal facial proportions. This case report shows Le Fort II distraction osteogenesis with this hybrid system for an Apert syndrome patient.

Case

The patient was a girl with Apert syndrome with midfacial-nose hypoplasia and skeletal class III malocclusion. She was healthy without respiratory problems and had no learning disabilities. She underwent our Le Fort II distraction osteogenesis with the hybrid system at 10 years and 6 months of age. Her midface was elongated 22 mm at point Or forward and moved 5° downward to the Frankfort horizontal plane compared to the standard position of average Japanese adult women on the cephalogram. Examining the facial image, the midfacial depression was improved 4 years after the operation.

Discussion

Overcorrection of midface advancement is required for patients to reduce the number of procedures during growth. The system that we developed could control the distance and vector of movement steadily when the central midface was overcorrected to try to create normal adult facial proportions.

Midface Morphology and Growth in Syndromic Craniosynostosis Patients Following Frontofacial Monobloc Distraction

BACKGROUND

Facial advancement represents the essence of the surgical treatment of syndromic craniosynostosis. Frontofacial monobloc distraction is an effective surgical approach to correct midface retrusion although someone consider it very hazardous procedure. The authors evaluated a group of patients who underwent frontofacial monobloc distraction with the aim to identify the advancement results performed in immature skeletal regarding the midface morphologic characteristics and its effects on growth.

METHODS

Sixteen patients who underwent frontofacial monobloc distraction with pre- and postsurgical computed tomography (CT) scans were evaluated and compared to a control group of 9 nonsyndromic children with CT scans at 1-year intervals during craniofacial growth. Three-dimensional measurements and superimposition of the CT scans were used to evaluate midface morphologic features and longitudinal changes during the craniofacial growth and following the advancement. Presurgical growth was evaluated in 4 patients and postsurgical growth was evaluated in 9 patients.

RESULTS

Syndromic maxillary width and length were reduced and the most obtuse facial angles showed a lack in forward projection of the central portion in these patients. Three-dimensional distances and images superimposition demonstrated the age did not influence the course of abnormal midface growth.

CONCLUSION

The syndromic midface is hypoplastic and the sagittal deficiency is associated to axial facial concavity. The advancement performed in mixed dentition stages allowed the normalization of facial position comparable to nonsyndromic group. However, the procedure was not able to change the abnormal midface architecture and craniofacial growth.

A novel RBF-based predictive tool for facial distraction surgery in growing children with syndromic craniosynostosis

Purpose

Predicting changes in face shape from corrective surgery is challenging in growing children with syndromic craniosynostosis. A prediction tool mimicking composite bone and skin movement during facial distraction would be useful for surgical audit and planning. To model surgery, we used a radial basis function (RBF) that is smooth and continuous throughout space whilst corresponding to measured distraction at landmarks. Our aim is to showcase the pipeline for a novel landmark-based, RBF-driven simulation for facial distraction surgery in children.

Methods

An individual’s dataset comprised of manually placed skin and bone landmarks on operated and unoperated regions. Surgical warps were produced for ‘older’ monobloc, ‘older’ bipartition and ‘younger’ bipartition groups by applying a weighted least-squares RBF fitted to the average landmarks and change vectors. A ‘normalisation’ warp, from fitting an RBF to craniometric landmark differences from the average, was applied to each dataset before the surgical warp. The normalisation was finally reversed to obtain the individual prediction. Predictions were compared to actual post-operative outcomes.

Results

The averaged change vectors for all groups showed skin and bone movements characteristic of the operations. Normalisation for shape–size removed individual asymmetry, size and proportion differences but retained typical pre-operative shape features. The surgical warps removed the average syndromic features. Reversing the normalisation reintroduced the individual’s variation into the prediction. The mid-facial regions were well predicted for all groups. Forehead and brow regions were less well predicted.

Conclusions

Our novel, landmark-based, weighted RBF can predict the outcome for facial distraction in younger and older children with a variety of head and face shapes. It can replicate the surgical reality of composite bone and skin movement jointly in one model. The potential applications include audit of existing patient outcomes, and predicting outcome for new patients to aid surgical planning.

Classification of Subtypes of Apert Syndrome, Based on the Type of Vault Suture Synostosis

Supplemental Digital Content is available in the text.

Background:

Apert syndrome patients are different in clinical pathology, including obstructive sleep apnea, cleft palate, and mental deficiency. These functional deficiencies may be due to anatomic deformities, which may be caused by different forms of associated suture fusion. Therefore, a classification system of Apert syndrome based on the type of craniosynostosis pattern might be helpful in determining treatment choices.

Methods:

CT scans of 31 unoperated Apert syndrome and 51 controls were included and subgrouped as: class I. Bilateral coronal synostosis; class II. Pansynostosis; and class III. Perpendicular combination synostosis: a. unilateral coronal and metopic synostosis; b. sagittal with bilateral/unilateral lambdoid synostosis; and c. others.

Results:

Class I is the most common (55%) subtype. The cranial base angulation of class I was normal; however, the cranial base angulation on the cranium side of the skull in class II increased 12.16 degrees (P = 0.006), whereas the facial side cranial base angle of class IIIa decreased 4.31 degrees (P = 0.035) over time. The external cranial base linear measurements of class I showed more evident reduction in anterior craniofacial structures than posterior, whereas other subtypes developed more severe shortening in the posterior aspects.

Conclusions:

Bicoronal synostosis is the most common subtype of Apert syndrome with the normalized cranial base angulation. Combined pansynostosis patients have flatter cranial base, whereas the combined unilateral coronal synostosis have a kyphotic cranial base. Class I has more significant nasopharyngeal airway compromise in a vertical direction, whereas classes II and III have more limited oropharyngeal space.

The Effect of Midface Advancement Surgery on Obstructive Sleep Apnoea in Syndromic Craniosynostosis

BACKGROUND

Children with syndromic craniosynostosis frequently suffer from obstructive sleep apnoea (OSA). The aim of the authors' study was to investigate if midface advancement surgery for patients with SC improved the severity of OSA by examining the results of sleep studies before and after surgery.

METHODS

A retrospective comparison of the pre and postoperative sleep study data of children undergoing midface advancement surgery at Great Ormond Street Hospital between 2007 and 2016.

RESULTS

A total of 65 children underwent midface advancement surgery between 2007 and 2016 at Great Ormond Street Hospital and had recorded pre- and postoperative sleep studies. Thirteen patients were excluded from the analysis as their sleep study techniques before and after surgery were not comparable (e.g., different conditions with prong/continuous positive airway pressure use). Fifty-six percent of the patients were treated by monobloc surgery and the remainder with bipartition surgery. A greater proportion of patients had a normal OSA grading following midface advancement (42.3% postoperatively vs. 23.1% preoperatively, P = 0.059) although no statistically significant categorical changes in OSA grade were observed. Seventy-one percent of the patients had a decrease in Apnoea-Hypopnoea Index after surgery (21 patients 2011 onward). Similarly, there was no significant change in median oxygen desaturation index or in oxygen saturation nadir following surgery.

CONCLUSION

The authors report one of the largest reviews of the effects of midface advancement surgery on sleep study parameters. Most patients showed improvements in Apnoea-Hypopnoea Index and OSA grading, although measures of oxygenation showed no consistent change.

A novel soft tissue prediction methodology for orthognathic surgery based on probabilistic finite element modelling

Repositioning of the maxilla in orthognathic surgery is carried out for functional and aesthetic purposes. Pre-surgical planning tools can predict 3D facial appearance by computing the response of the soft tissue to the changes to the underlying skeleton. The clinical use of commercial prediction software remains controversial, likely due to the deterministic nature of these computational predictions. A novel probabilistic finite element model (FEM) for the prediction of postoperative facial soft tissues is proposed in this paper. A probabilistic FEM was developed and validated on a cohort of eight patients who underwent maxillary repositioning and had pre- and postoperative cone beam computed tomography (CBCT) scans taken. Firstly, a variables correlation assessed various modelling parameters. Secondly, a design of experiments (DOE) provided a range of potential outcomes based on uniformly distributed input parameters, followed by an optimisation. Lastly, the second DOE iteration provided optimised predictions with a probability range. A range of 3D predictions was obtained using the probabilistic FEM and validated using reconstructed soft tissue surfaces from the postoperative CBCT data. The predictions in the nose and upper lip areas accurately include the true postoperative position, whereas the prediction under-estimates the position of the cheeks and lower lip. A probabilistic FEM has been developed and validated for the prediction of the facial appearance following orthognathic surgery. This method shows how inaccuracies in the modelling and uncertainties in executing surgical planning influence the soft tissue prediction and it provides a range of predictions including a minimum and maximum, which may be helpful for patients in understanding the impact of surgery on the face.

Primary aesthetic correction of nasal anomaly with costal graft in treating orbital hypertelorism

Orbital hypertelorism is a common congenital craniofacial anomaly in Asians. As Tessier pointed out, the correction of hypertelorism is effectively the correction of the nasal deformity, which is characterized by a broad, flat nose accompanying an increased interorbital distance and a lack of nasal projection.

OBJECTIVES

To measure the changes in the orbital and nasal parameters after Tessier box osteotomy and primary aesthetic rhinoplasty, performed concurrently with otogenous costochondral graft.

METHODS

From 2009 to 2013, 49 hypertelorism patients were treated in our craniofacial unit. Correction involved a classic Tessier box osteotomy combined with aesthetic augmentation and reconstruction of the nasal dorsum using a costochondral graft. All patients underwent photographic and tomographic documentation both before and 12 months after surgery. Patients underwent morphometric analysis to document the change in interorbital distance, IOD, hypertelorism index, and aesthetic nasal parameters, including the nasal dorsum and alar width, the nasal dorsal height, and the index of nasal apex protrusion versus nasal length.

RESULTS

All patients were satisfied with the outcome of the combined orbital and nasal repair. Morphometric analysis indicated that the IOD, hypertelorism index, and aesthetic nasal parameters all improved following surgery. The resorption rate of the costochondral graft was 16-19%, and graft warpage was nearly absent. Although complications included infection, cerebrospinal fluid leak, and hyposomia, no severe or life-threatening complications occurred.

CONCLUSION

Tessier box osteotomy with primary aesthetic rhinoplasty using costochondral grafts has shown to be efficacious in the treatment of patients with hypertelorism.

What's New in Syndromic Craniosynostosis Surgery?

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Understand the role of prenatal screening and counseling of parents of unborn children with syndromic craniosynostosis. 2. Recognize the genetic abnormalities, craniofacial phenotype, associated anomalies, and challenges associated with each of the five major forms of syndromic craniosynostosis. 3. Identify the pros and cons associated with timing and types of cranial vault remodeling techniques in this patient population. 4. Understand the risks and benefits associated with midface advancement with Le Fort III, Le Fort II plus zygomatic repositioning, monobloc, and facial bipartition. 5. Understand the important role of psychological counseling throughout childhood in this at-risk group.

SUMMARY

Crouzon, Apert, Pfeiffer, Muenke, and Saethre-Chotzen syndromes are the five most common forms of syndromic craniosynostosis. Although each has different genetic underpinnings and associated anomalies, their hallmark finding is turribrachycephaly most often associated with bicoronal craniosynostosis. The role of prenatal screening and counseling is growing, with caregivers becoming involved before birth. Multidisciplinary care from birth onward involves craniofacial plastic surgeons, neurosurgeons, otolaryngologists, ophthalmologists, orthodontists, anesthesiologists, psychologists, speech therapists, and geneticists. Early partial, or regional, craniectomy may be urgently indicated in multisuture cases with signs of increased intracranial pressure. Others may be managed successfully with posterior cranial vault distraction, middle vault expansion, or fronto-orbital advancement. Some authors have advocated early monobloc advancement for those patients who require acute airway intervention and globe protection, although the risks of these procedures are high. Many patients will require midfacial advancement with a Le Fort III, Le Fort II plus zygomatic repositioning, monobloc, or facial bipartition. The indications, risks, and benefits for each midfacial procedure must be considered, as this step in the treatment algorithm may carry the greatest functional and aesthetic benefits but also the potential for the greatest morbidity. At the culmination of facial growth, it is not uncommon for patients to require conventional orthognathic surgery and other bony contouring and soft-tissue procedures. Finally, an understanding of the psychological aspects of craniofacial difference, both in affected individuals and in their families, is essential to a successful, holistic approach.

Advances in the Treatment of Syndromic Midface Hypoplasia Using Monobloc and Facial Bipartition Distraction Osteogenesis

Midface hypoplasia or retrusion remains a persistent feature of syndromic craniosynostosis years after successful treatment of the cranium. Although expansion of the cranial vault in infancy by traditional fronto-orbital advancement, posterior expansion, or both, can treat the immediate intracranial constriction, midface hypoplasia and its stigmata of exorbitism, sleep apnea, central face concavity, and malocclusion remain suboptimally treated. Initial enthusiasm for the procedures was tempered due to a high rate of infectious complications; timing and indications for surgery continue to stir controversy. During the last decade renewed interest with the monobloc and facial bipartition procedure using distraction osteogenesis with either an internal or external distraction system has decreased morbidity significantly. These procedures have re-emerged as powerful and comprehensive tools in the treatment of syndromic midface hypoplasia.

Frontofacial surgery in children and adolescents: techniques, indications, outcomes

The techniques of frontofacial surgery are most valuable in the clinical management of complex craniofacial deformity to achieve a range of functional and aesthetic gains in children from infancy to maturity. A variety of complex craniofacial osteotomies that can be used to separate the orbits from the skull base have been described. In addition, the combination of circumorbital release and pterygomaxillary disjunction allows advancement of the orbitomaxillary segment for powerful clinical benefit. For the purpose of this article, the principal frontofacial strategies include the monobloc frontofacial advancement by distraction (MBD), frontofacial bipartition advancement by distraction (BpD), orbital box osteotomy (FFBx), and frontofacial bipartition (FFBp). These techniques are broadly used for two purposes: to allow for the translocation of one or both orbits to correct orbitofacial disproportion (hypertelorism, vertical orbital dystopia, or a combination of both), or to advance the orbitomaxillary segment for orbital volume expansion and protection of the eye in syndromes featuring severe exorbitism (oculo-orbital disproportion). Here we describe aspects of our experience of frontofacial surgery in the Craniofacial Centre at Great Ormond Street Hospital for Children, London, with reference to the principles underpinning frontofacial surgical techniques, their challenges, and their impact on function and aesthetics.