Normalizing facial ratios in apert syndrome patients with Le Fort II midface distraction and simultaneous zygomatic repositioning

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.

Comparison of Internal and External Distraction in Frontofacial Monobloc Advancement: A Three-Dimensional Quantification

BACKGROUND

Crouzon syndrome is characterized by complex craniosynostosis and midfacial hypoplasia. Where frontofacial monobloc advancement (FFMBA) is indicated, the method of distraction used to achieve advancement holds an element of equipoise. This two-center retrospective cohort study quantifies the movements produced by internal or external distraction methods used for FFMBA. Using shape analysis, this study evaluates whether the different distraction forces cause plastic deformity of the frontofacial segment, producing distinct morphologic outcomes.

METHODS

Patients with Crouzon syndrome who underwent FFMBA with internal distraction [Hôpital Necker-Enfants Malades (Paris, France)] or external distraction [Great Ormond Street Hospital for Children (London, United Kingdom)] were compared. Digital Imaging and Communications in Medicine files of preoperative and postoperative computed tomographic scans were converted to three-dimensional bone meshes and skeletal movements were assessed using nonrigid iterative closest point registration. Displacements were visualized using color maps and statistical analysis of the vectors was undertaken.

RESULTS

Fifty-one patients met the strict inclusion criteria. Twenty-five underwent FFMBA with external distraction and 26 with internal distraction. External distraction provides a preferential midfacial advancement, whereas internal distractors produce a more positive movement at the lateral orbital rim. This confers good orbital protection but does not advance the central midface to the same extent. Vector analysis confirmed this to be statistically significant ( P < 0.01).

CONCLUSIONS

Morphologic changes resulting from monobloc surgery differ depending on the distraction technique used. Although the relative merits of internal and external distraction still stand, it may be that external distraction is more suited to addressing the midfacial biconcavity seen in syndromic craniosynostosis.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Optimizing Facial Esthetic Outcomes: Adding Distraction Osteogenesis to Your Classic Orthognathic Surgery Armamentarium

Classical orthognathic procedures have long been known to improve the facial esthetic contours and proportions of face by restoring the skeletal foundation, on which the soft-tissue drapes. Distraction osteogenesis was introduced to solve complex skeletal abnormalities in patients with craniofacial conditions that could not be solved by classical orthognathic surgery techniques. The gradual expansion in this group of patients showed not only greater skeletal stability, but the expansion at various tissue planes improved the facial appearance. In this report we review our experience in 22 cases with dentofacial skeletal abnormities for whom we believe achieved aesthetic outcomes could not habe been with classical orthognathic techniques alone. In addition, distraction at the interdental regions allowed for "tailoring" of the osteotomies and for simultaneous expansion at the occlusal level.

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.

Subcranial Midface Advancement in Patients with Syndromic Craniosynostosis

Patients with syndromic craniosynostosis can present with midface hypoplasia, abnormal facial ratios, and obstructive sleep apnea. These symptoms can all be improved with midface advancement, but it is essential to evaluate the specific morphologic characteristics of each patient's bony deficiencies before offering subcranial advancement. Midface hypoplasia in Crouzon syndrome is evenly distributed between the central and lateral midface and reliably corrected with Le Fort III distraction. In contrast, the midface hypoplasia in Apert/Pfeiffer syndromes occurs in both an axial and a sagittal plane, with significantly more nasomaxillary hypoplasia compared with the orbitozygomatic deficiency.

Influence of Nonsyndromic Bicoronal Synostosis and Syndromic Influences on Orbit and Periorbital Malformation

BACKGROUND

Oculoorbital disproportion in patients with craniosynostosis has similarities and dissimilarities between syndromic and nonsyndromic cases. The authors hypothesized that these two conditions have specific individual influences as they relate to development of the orbital and periorbital skeletons.

METHODS

A total of 133 preoperative computed tomography scans (nonsyndromic bicoronal synostosis, n = 38; Apert syndrome bicoronal synostosis subtype, n = 33; Crouzon syndrome bicoronal synostosis subtype, n = 10; controls, n = 52) were included. Craniometric and volumetric analyses related to the orbit and periorbital anatomy were performed.

RESULTS

Orbital cavity volume was mildly restricted in nonsyndromic bicoronal synostosis (7 percent, p = 0.147), but more so in Apert and Crouzon syndromes [17 percent (p = 0.002) and 21 percent (p = 0.005), respectively]. The sphenoid side angle in Apert syndrome was wider than when compared to Crouzon syndrome (p = 0.043). The ethmoid side angle in Apert patients, however, was narrower (p = 0.066) than that in Crouzon patients. Maxilla anteroposterior length was more restricted in Apert syndrome than Crouzon syndrome (21 percent, p = 0.003) and nonsyndromic cases (26 percent, p < 0.001). The posterior nasal spine position was retruded in Crouzon syndrome (39 percent, p < 0.001), yet the anterior nasal spine position was similar in Apert and Crouzon syndromes.

CONCLUSIONS

Orbit and periorbital malformation in syndromic craniosynostosis is likely the combined influence of syndromic influences and premature suture fusion. Apert syndrome expanded the anteriorly contoured lateral orbital wall associated with bicoronal synostosis, whereas Crouzon syndrome had more infraorbital rim retrusion, resulting in more severe exorbitism. Apert syndrome developed maxillary hypoplasia, in addition to the maxillary retrusion, observed in Crouzon syndrome and nonsyndromic bicoronal synostosis patients.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Applications of three-dimensional surgical planning in facial feminization surgery: A systematic review

BACKGROUND

Despite some reports that have shown an increase in safety, efficiency, and accuracy during feminizing craniofacial procedures utilizing three-dimensional (3D) technology, there are no reports summarizing the available evidence on this matter for facial feminization surgery (FFS). Here, we aimed to systematically review the application of 3D technology on FFS.

METHODS

We conducted a comprehensive search across PubMed, SCOPUS, Ovid MEDLINE®, Web of Science, and ScienceDirect looking for studies reporting the use of 3D surgical planning in the setting of FFS following the PRISMA guidelines. We extracted data on photographic assessment, imaging, surgical application, and surgical technique and outcomes.

RESULTS

This review included 10 studies comprising 1473 transgender female patients and 50 cadaveric cranial specimens. Four studies employed virtual surgical planning (VSP) and the concomitant use of prefabricated cutting guides. One study reported the implementation of 3D VSP using a female skull as a reference. One study used computer-aided design cutting guides and custom plates for FFS. Standardized incorporation of 3D printed models allowed for preoperative planning in three studies. Three studies reported VSP using 3D reconstruction of CT images, but without the use of 3D printing. Three studies used 3D photography with specialized camera technology to enrich clinical documentation and provide a comprehensive facial analysis of soft tissue. Accuracy ranged from 85.7% to 97%. Morbidity ranged from 0% to 12.5%.

CONCLUSION

Based on this data, we believe 3D VSP has promising outcomes in terms of accuracy and low morbidity, encouraging its implementation in FFS. However, further prospective double-arm cohort studies are required.

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.

Syndromic Craniosynostosis: Unique Management Considerations

Craniosynostosis involves the premature fusion of 1 or more cranial sutures and commonly presents as an isolated, nonsyndromic diagnosis. A subset of patients have syndromic craniosynostosis. Several unique considerations must be taken into account when managing patients with syndromic craniosynostosis. A multidisciplinary craniofacial team with a central coordinator is particularly useful for coordinating care among various specialists, and close monitoring is mandatory owing to the increased risk of intracranial hypertension. Surgical management varies among centers, but core options include fronto-orbital advancement with cranial vault remodeling, posterior vault expansion, endoscopic-assisted suturectomy with postoperative orthotic therapy, and midface advancement.

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.

Morphological Basis for Airway Surgical Intervention in Apert Syndrome

OBJECTIVE

Previous studies have explored the restricted nasopharyngeal airway in Apert syndrome patients. This study aims to investigate the segmented airway volume changes with age and directly analyze their correlations with subcranial dimensions and angulations.

METHODS

Ninety-seven preoperative computed tomography scans (Apert, n = 44; control, n = 53) were included in this study, and divided into 5 age-related subgroups. Computed tomography scans were measured using Mimics and 3-matics software.

RESULTS

Before 6 months of age, the nasal cavity in Apert syndrome is reduced by 47% (P = 0.002), which gradually approximates normal thereafter; however, there remained a 30% reduction, compared with controls. It is highly correlated with the anteroposterior length of subcranial space, and the position of maxilla and palate. The pharyngeal airway volume in Apert syndrome patients, younger than 6 months, was larger than normal by 129% (P = 0.013). However, between 2 and 6 years of age, the pharyngeal airway becomes smaller than normal, with a 57% (P = 0.010) reduction in childhood and 52% (P = 0.005) in adolescence. It is closely correlated with the intercondylar and intergonial widths.

CONCLUSIONS

Airway compromise in Apert syndrome patients is attributable more to the nasal cavity in infants, but in the older child, it is the pharyngeal region. The restricted nasal airway in Apert syndrome is correlated with the subcranial space length and width, but independent of cranial base flexion. The pharyngeal airway volume in Apert syndrome is not as highly correlated with craniofacial morphology. Rather, it is impacted by the growth of mandible, which often requires surgical intervention later in childhood.

Le Fort II Distraction with Simultaneous Zygomatic Repositioning

Severe midface hypoplasia is often managed by Le Fort III distraction. Le Fort II distraction with zygomatic repositioning is a modification of the Le Fort III distraction operation aimed to correct abnormal facial ratios of patients with greater central than lateral midface deficiency. The operation starts with Le Fort III osteotomies and is followed by separation and fixation of bilateral zygomas. The central nasomaxillary Le Fort II segment is then distracted to achieve independent movements of the central and lateral midface. The Le Fort II zygomatic repositioning operation has become our procedure of choice for patients with Apert facial dysmorphology.

Distraction Osteogenesis: Mandible and Maxilla

Mandibular and maxillary deformities commonly require surgical intervention. Prior to distraction osteogenesis, traditional modalities involving single-staged translocation and rigid fixation were used to correct these craniofacial anomalies. Distraction osteogenesis has evolved as a compelling alternative for treating aesthetic and functional dentofacial defects. The process of distraction osteogenesis involves three phases-latency, activation, and consolidation-which allow for appropriate translation of the affected craniofacial skeleton. This review will cover the role of distraction for managing congenital and acquired deformities of the mandible and maxilla. This novel technique can be performed at numerous anatomical sites along the craniofacial skeleton to treat a variety of anomalies, which serves as a testament to its adaptability and efficacy. Importantly, distraction osteogenesis also has the ability to simultaneously increase bone length and the overlying soft tissue envelope. This advantage results in larger advancements with reduced relapse rates and improved patient satisfaction. While complications remain a concern, it stands to reason that the measurable benefits observed underscore the power and versatility of distraction osteogenesis.

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.

Evolution of Cranioorbital Shape in Nonsyndromic, Muenke, and Saethre-Chotzen Bilateral Coronal Synostosis: A Case-Control Study of 2-Year Outcomes

BACKGROUND

The purpose of this study was to quantify change in cranioorbital morphology from presentation, after fronto-orbital advancement, and at 2-year follow-up.

METHODS

Volumetric, linear, and angular analyses were performed on computed tomographic scans of consecutive bilateral coronal synostosis patients. Comparisons were made across three time points, between syndromic and nonsyndromic cases, and against normal controls. Significance was set at p < 0.05.

RESULTS

Twenty-five patients were included: 11 were nonsyndromic, eight had Saethre-Chotzen syndrome, and six had Muenke syndrome. Total cranial volume was comparable to normal, age-matched control subjects before and 2 years after surgery despite an expansion during surgery. Axial and sagittal vector analyses showed advancement and widening of the lower forehead beyond control values with surgery and comparable anterior position, but increased width compared to controls at 2 years. Frontal bossing decreased with a drop in anterior cranial height and advanced lower forehead position. Middle vault height was not normalized and turricephaly persisted at follow-up. Posterior fossa volume remained lower at all three time points compared to control subjects. Supraorbital retrusion relative to anterior corneal position was overcorrected by surgery, with values comparable to those of control subjects at 2 years because of differential growth. There was no difference at 2 years between syndromic and nonsyndromic groups.

CONCLUSIONS

Open fronto-orbital advancement successfully remodels the anterior forehead but requires overcorrection to be comparable to normal at 2 years. Although there are differences in syndromic cases at presentation, they do not result in significant morphometric differences on follow-up. Posterior fossa volume remains lower at all time points.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Spring-assisted posterior vault expansion-a single-centre experience of 200 cases

PURPOSE

Children affected by premature fusion of the cranial sutures due to craniosynostosis can present with raised intracranial pressure and (turri)brachycephalic head shapes that require surgical treatment. Spring-assisted posterior vault expansion (SA-PVE) is the surgical technique of choice at Great Ormond Street Hospital for Children (GOSH), London, UK. This study aims to report the SA-PVE clinical experience of GOSH to date.

METHODS

A retrospective review was carried out including all SA-PVE cases performed at GOSH between 2008 and 2020. Demographic and clinical data were recorded including genetic diagnosis, craniofacial surgical history, surgical indication and assessment, age at time of surgery (spring insertion and removal), operative time, in-patient stay, blood transfusion requirements, additional/secondary (cranio)facial procedures, and complications.

RESULTS

Between 2008 and 2020, 200 SA-PVEs were undertaken in 184 patients (61% male). The study population consisted of patients affected by syndromic (65%) and non-syndromic disorders. Concerns regarding raised intracranial pressure were the surgical driver in 75% of the cases, with the remainder operated for shape correction. Median age for SA-PVE was 19 months (range, 2-131). Average operative time for first SA-PVE was 150 min and 87 for spring removal. Median in-patient stay was 3 nights, and 88 patients received a mean of 204.4 ml of blood transfusion at time of spring insertion. A single SA-PVE sufficed in 156 patients (85%) to date (26 springs still in situ at time of this analysis); 16 patients underwent repeat SA-PVE, whilst 12 underwent rigid redo. A second SA-PVE was needed in significantly more cases when the first SA-PVE was performed before age 1 year. Complications occurred in 26 patients with a total of 32 events, including one death. Forty-one patients underwent fronto-orbital remodelling at spring removal and 22 required additional cranio(maxillo)facial procedures.

CONCLUSIONS

Spring-assisted posterior vault expansion is a safe, efficient, and effective procedure based on our 12-year experience. Those that are treated early in life might require a repeat SA-PVE. Long-term follow-up is recommended as some would require additional craniomaxillofacial correction later in life.

Magnitude of Horizontal Advancement is Associated With Apnea Hypopnea Index Improvement and Counter-Clockwise Maxillary Rotation After Subcranial Distraction for Syndromic Synostosis

PURPOSE

Subcranial midface distraction is used to treat central midface deficiency in syndromic synostosis. Our aim was to determine which maxillary movements were associated with improvement in measures of obstructive sleep apnea.

METHODS

This was a retrospective cohort study that reviewed patients with syndromic midface retrusion and documented sleep apnea who underwent subcranial midface distraction via either Le Fort 3 osteotomy or Le Fort 2 osteotomy with zygomatic repositioning. The predictor variables measured on cephalograms were the magnitude and direction of midface and mandibular movements. The primary outcome was the change in the apnea hypopnea index (AHI) from polysomnography before and after surgery. The secondary outcomes were volumes of upper airway containing bone spaces calculated from computed tomography scans. Data analysis included linear regression to estimate the effect of distraction vectors on bone space volumes and AHI changes.

RESULTS

We included 18 patients primarily with Crouzon or Apert syndrome. The magnitude of distraction in a horizontal direction was the most significant factor for AHI improvement and primarily expanded the nasopharyngeal space, but with a smaller impact on the oral cavity space. Clockwise palate rotation was most influenced by a downward direction of distraction, with 24° below horizontal creating a neutral advancement. The greater the magnitude of advancement, the more likely a counterclockwise rotation was observed.

CONCLUSIONS

Horizontal magnitude of advancement had the greatest impact on AHI improvement. Vertical lengthening and closure of anterior open bite deformities can be done without compromising airway results as long as total advancement is not compromised. Palate rotation is best controlled by a downward distraction vector, but counterclockwise rotation increases with greater advancement.

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.

Surgical-Orthodontic Considerations in Subcranial and Frontofacial Distraction

Subcranial and frontofacial distraction osteogenesis have emerged as powerful tools for management of hypoplasia involving the upper two-thirds of the face. The primary goal of subcranial or frontofacial distraction is to improve the orientation of the upper face and midface structures (frontal bone, orbitozygomatic complex, maxilla, nasal complex) relative to the cranial base, globes, and mandible. The various techniques used are tailored for management of specific phenotypic differences in facial position and may include segmental osteotomies, differential vectors, or synchronous maxillomandibular rotation.

Zygomatic Rotation-Advancement: A New Concept for the Correction of Exorbitism in Patients With Syndromic Craniosynostosis

BACKGROUND

The exophthalmos and class III malocclusion seen in Crouzon syndrome can be treated by Le Fort III advancement/distraction. However, reconstructive options for zygomatic retrusion are limited. The authors describe the repair of isolated exorbitism in a patient with Crouzon syndrome, via bilateral zygomatic rotation-advancement.

METHODS

A 34-year-old woman with Crouzon syndrome complained of exorbitism and malar hypoplasia. Four years prior, she declined Le Fort III advancement and underwent orthodontic/orthognathic correction of malocclusion. Radiographs were used to develop a computerized surgical plan. Bilateral periorbital osteotomy with advancement/rotation of the zygomatic process was performed using custom osteotomy guides and plates. Images obtained immediately postoperative and 3- and 19-month postoperative were compared to assess surgical stability, accuracy, and soft tissue changes.

RESULTS

Decreased globe exposure and increased malar prominence have improved facial balance. Superimposed pre- and postoperative radiographs demonstrate bilateral advancement of the zygomatic body and inferior orbital rim. Superimposition of immediate postoperative and 19-month radiographs showed no relapse. Soft tissue histogram showed increased prominence of the malar eminence, lateral orbital rim, and cheek.

CONCLUSIONS

Zygomatic rotation-advancement proved a safe, effective, stable, and predictable treatment for isolated malar hypoplasia in a patient with Crouzon syndrome. Virtual planning can enhance novel complex craniofacial procedures.

Midfacial Bony Remodeling

Craniofacial procedures to the midface in conjunction with work to the upper face and skull, and if needed the lower jaw, are a permanent and effective way to achieve feminization of the face in transgender patients. Although the surgery is more complex than other procedures, it should be considered for select patients. Further improvement of cosmesis may be considered a separate surgical entity and is not limited in scope or time by having undergone midface osteotomies. When carefully planned, bony surgery to the midface is safe and results in long-term predictive results and a favorable appearance as the patient ages."

Syndromic Craniosynostosis: Complexities of Clinical Care

Patients with syndromic craniosynostosis have a molecularly identified genetic cause for the premature closure of their cranial sutures and associated facial and extra-cranial features. Their clinical complexity demands comprehensive management by an extensive multidisciplinary team. This review aims to marry genotypic and phenotypic knowledge with clinical presentation and management of the craniofacial syndromes presenting most frequently to the craniofacial unit at Great Ormond Street Hospital for Children NHS Foundation Trust.

Retroposition of the Globe After Le Fort III Midfacial Distraction

BACKGROUND

Patients with syndromic craniosynostosis exhibit exorbitism due to supraorbital and midfacial retrusion. This study documented the change in sagittal orbital-globe relationship following Le Fort III midfacial advancement.

METHODS

This retrospective case series comprised patients with syndromic craniosynostosis who underwent midfacial distraction from 1997 to 2016. Changes in sagittal globe position in relation to the orbital rims were measured by pre- and postoperative direct anthropometry, computed tomographic scans, or both methods. Descriptive statistics were calculated; significance was set at P < 0.05.

RESULTS

Anthropometry showed a significant increase from superior orbital rim-to-corneal apex (os-acor) (4.1 ± 4.0 mm, P < 0.001) and from inferior orbital rim-to-corneal apex (oi-acor) (4.5 ± 5.3 mm, P < 0.001). The lateral orbital rim to the corneal apex (ol-acor) dimension did not change significantly. Computed tomography measurements confirmed retropositioned globes relative to the anterior border of the orbital cavity (2.5 ± 6.4 mm, P = 0.036). The 2 analytic methods yielded statistically similar results.

CONCLUSION

The globes move posteriorly a mean of 2.5 to 4.5 mm following Le Fort III midfacial distraction in patients with syndromic craniosynostosis. This finding is useful in attaining euophthalmos when planning and executing this procedure.

Three-dimensional imaging of soft and hard facial tissues in patients with craniofacial syndromes: a systematic review of methodological quality

OBJECTIVES

To systematically review the methodological quality of three-dimensional imaging studies of patients with craniofacial syndromes and to propose recommendations for future research.

METHODS

PubMed, Embase and Cochrane databases as well as Grey literature were electronically searched. Inclusion criteria were patients with genetic syndromes with craniofacial manifestations and three-dimensional imaging of facial soft and/or hard tissues. Exclusion criteria consisted of non-syndromic conditions or conditions owing to environmental causes, injury or trauma, facial soft and hard tissues not included in the image analysis, case reports, reviews, opinion articles. No restrictions were made for patients' ethnicity nor age, publication language or publication date. Study quality was evaluated using the Methodological Index for Non-Randomized Studies (MINORS).

RESULTS

The search yielded 2228 citations of which 116 were assessed in detail and 60 were eventually included in this review. Studies showed a large heterogeneity in study design, sample size and patient age. An increase was observed in the amount of studies with time, and the imaging method most often used was CT. The most studied craniofacial syndromes were Treacher Collins, Crouzon and Apert syndrome. The articles could be divided into three main groups: diagnostic studies (34/60, 57%), evaluation of surgical outcomes (21/60, 35%) and evaluation of imaging techniques (5/60, 8%). For comparative studies, the median MINORS score was 13 (12-15, 25-75th percentile), and for non-comparative studies, the median MINORS score was 8 (7-9, 25-75th percentile).

CONCLUSIONS

The median MINORS scores were only 50 and 54% of the maximum scores and there was a lack of prospective, controlled trials with sufficiently large study groups. To improve the quality of future studies in this domain and given the low incidence of craniofacial syndromes, more prospective multicentre controlled trials should be set up.

Pediatric Obstructive Sleep Apnea: Consensus, Controversy, and Craniofacial Considerations

Pediatric obstructive sleep apnea, characterized by partial or complete obstruction of the upper airway during sleep, is associated with multiple adverse neurodevelopmental and cardiometabolic consequences. It is common in healthy children and occurs with a higher incidence among infants and children with craniofacial anomalies. Although soft-tissue hypertrophy is the most common cause, interplay between soft tissue and bone structure in children with craniofacial differences may also contribute to upper airway obstruction. Snoring and work of breathing are poor predictors of obstructive sleep apnea, and the gold standard for diagnosis is overnight polysomnography. Most healthy children respond favorably to adenotonsillectomy as first-line treatment, but 20 percent of children have obstructive sleep apnea refractory to adenotonsillectomy and may benefit from positive airway pressure, medical therapy, orthodontics, craniofacial surgery, or combined interventions. For children with impairment of facial skeletal growth or craniofacial anomalies, rapid maxillary expansion, midface distraction, and mandibular distraction have all been demonstrated to have therapeutic value and may significantly improve a child's respiratory status. This Special Topic article reviews current theories regarding the underlying pathophysiology of pediatric sleep apnea, summarizes standards for diagnosis and management, and discusses treatments in need of further investigation, including orthodontic and craniofacial interventions. To provide an overview of the spectrum of disease and treatment options available, a deliberately broad approach is taken that incorporates data for both healthy children and children with craniofacial anomalies.

Subcranial and orthognathic surgery for obstructive sleep apnea in achondroplasia

PURPOSE

Obstructive sleep apnea (OSA) is a common problem in patients with achondroplasia. The purpose of this study was to assess changes in airway volumes following various degrees of facial skeletal advancement.

METHODS

This was a retrospective evaluation of patients with achondroplasia who underwent facial skeletal advancement for obstructive sleep apnea. Patients were treated with either an isolated Le Fort III distraction (LF3) or Le Fort II distraction with or without subsequent Le Fort I and bilateral sagittal split osteotomies (LF2 ± LF1/BSSO). Demographic, cephalometric, volumetric, and polysomnographic variables were recorded pre- and postoperatively.

RESULTS

Six patients with achondroplasia underwent midface advancement for treatment of OSA (2 LF2 + LF1/BSSO, 2 LF2, 2 LF3). Patients undergoing LF2 + LF1/BSSO had consistent volumetric improvements at the nasopharyngeal and oropharyngeal levels (Δ ≥ +347% and ≥+253%, respectively). Patients undergoing LF2 alone had consistent improvement in the nasopharyngeal airway alone (Δ ≥ +214%). Patients undergoing LF3 alone had consistent, but less dramatic, changes in nasopharyngeal volume (Δ ≥ +97.1%). All patients undergoing LF2 distraction (with or without LF1/BSSO) had a ≥50% reduction in the apnea-hypopnea index (AHI) postoperatively; there was no improvement in AHI with LF3 alone.

CONCLUSION

In patients with achondroplasia-associated OSA there are variable improvements in airway volume. This preliminary report suggests that LF2 distraction, with or without subsequent LF1/BSSO, may provide consistent reductions in AHI relative to LF3 distraction.

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.

Corrected Cephalometric Analysis to Determine the Distance and Vector of Distraction Osteogenesis for Syndromic Craniosynostosis

Background:

The purpose of this study was to confirm the utility of a corrected cephalometric analysis to facilitate the planning of distraction osteogenesis with Le Fort III osteotomy for syndromic craniosynostosis.

Methods:

This prospective study involved 4 male and 2 female patients (mean patient age, 8 years 9 months; age range, 4 years 6 months to 13 years 2 months) with Crouzon syndrome who were treated with Le Fort III maxillary distraction using our previously described system of analysis of a corrected cephalogram and who underwent clinical follow-up. Lateral cephalograms were obtained immediately after device removal.

Results:

Distraction of orbitale moved the vector downward to the adult profile, but there was slightly less elongation than the adult profile for the distraction distance. The desired and real mean angles after distraction of point A were 29.2 ± 7.9° and 6.1 ± 8.5°, respectively, and the desired and the real mean distances after distraction of point A were 30.6 ± 12.7 mm and 29.4 ± 4.1 mm, respectively.

Conclusions:

Using the corrected cephalometric analysis, the distance and vector of distraction osteogenesis with Le Fort III osteotomy could be determined in patients with syndromic craniosynostosis. The distraction system brought the patients' facial bones to the planned position using controlling devices.

Midface Osteotomies for Feminization of the Facial Skeleton

Supplemental Digital Content is available in the text.

Facial feminization surgery is a term to describe the surgical alteration of a masculine facial appearance to a more feminine appearance, which is most commonly performed for male-to-female transsexual individuals. To alter the midfacial relations, segmentalized osteotomies were performed in selected patients expanding on the established techniques for facial feminization surgery. All patients underwent a preoperative 3D computerized tomography scan and 3D photography before and after the surgery. The inclusion of the midface in surgery was determined based on the relative projection and angle of the zygomatic body compared with the supraorbital region (the supraorbital region was reduced in all patients). Patients were prospectively followed up by 3D surface photography and 3D computerized tomography scans. Rotation and advancement of the zygomatic region was found to be an effective way to further feminize the midfacial appearance in selected male-to-female transsexual patients. No major surgical complications occurred. Although somewhat technically challenging, we suggest that midface surgery should be considered for feminizing purposes in order for the patient to achieve a long-term favorable result compared with other alternative methods.

Versatility of Distraction Osteogenesis for the Craniofacial Skeleton

Malformations of the craniofacial skeleton are common. Restoration of anatomic shape, size, and position has been traditionally accomplished using autologous bone grafting to fill gaps created by surgery and segmental movement. The authors present their practice using distraction in many different ages and settings over 20 years. A retrospective review was performed of all craniofacial patients treated using distraction osteogenesis for mandible, midface, and calvarium. The authors identified 205 patient. Mandible: 112 patients were treated at an average age of 3.4 years. 18.8% of patients required repeat distraction. There was no difference in the neonatal versus older group (P = 0.71). There were significantly higher reoperation rates in syndromic children (P < 0.01). Midface: 58 patients underwent Lefort III distraction at an average age of 13.6 years. One (1.7%) required repeat distraction (Miller syndrome). Five (8.6%) patients underwent subsequent Lefort I advancement for occlusal changes. Calvarium: 33 patients were treated at an average age of 4.7 years. No repeat distractions were performed. One patient required an additional advancement procedure. Distraction demonstrates successful long-term correction of defects in the craniofacial skeleton with the versatility and control needed to treat the wide spectrum of deformity.

Successful Treatment of Postoperative Mouth Opening Limitation Following Le Fort III Distraction with Bilateral Coronoidectomies

INTRODUCTION

Distraction osteogenesis is a powerful tool in craniomaxillofacial surgery, allowing for large advancements of osteotomized segments in the setting of a restrictive soft tissue envelope. Despite its benefits, distraction can have negative functional consequences. We present a case of a patient with Crouzon syndrome who developed reduced mouth opening capability after a Le Fort III midfacial advancement with rigid external distraction.

TECHNIQUE

Radiographic evaluation revealed that the coronoid process was restricting the normal excursion of the mandible by contacting the posterior zygoma. The patient was subsequently treated with a bilateral coronoidectomy via an intraoral approach, which improved his interincisal opening. Maximum interincisal distance was improved from 18 mm to 33 mm following bilateral cornoid resection.

CONCLUSION

We report coronoid impingement as a potential complication after Le Fort III distraction. Such a finding suggests the need for a detailed vector analysis in cases undergoing midface advancement with distraction. Post-distraction coronoidectomy is a useful surgical procedure to treat mouth opening limitation due to coronoid impingement against the zygoma after midfacial advancement.

Monobloc Le Fort III Distraction Osteogenesis for Correction of Severe Fronto-orbital and Midface Hypoplasia in Pediatric Crouzon Syndrome

In severe syndromic craniosynostosis, distraction osteogenesis (DO) provides superior segmental advancement and allows progressive clinical monitoring to ensure that adequate skeletal expansion is achieved. We report two cases of Crouzon syndrome involving a 3-year-old boy and a 4-year-old girl, who were both treated with monobloc Le Fort III DO using a combination of external and internal distraction devices (Synthes, Oberdorf, Switzerland) to treat severe orbital proptosis and obstructed nasopharyngeal airway secondary to severe hypoplastic craniofacial skeletal components. Their skeletal segments were advanced in daily increments by 27 mm and 23 mm, respectively. Results at 18 months postoperatively showed successful outcomes, as evidenced by adequate eye protection, tracheostomy tube decannulation following objective evidence of patent nasopharyngeal airway, and acceptable facial appearance. Monobloc Le Fort III DO using a combination of external and internal devices produces favorable functional and clinical outcomes for the treatment of severe orbital and airway discrepancy in Crouzon syndrome.

Withdrawal of Continuous Positive Airway Pressure Therapy after Malar Advancement and Le Fort II Distraction in a Case of Apert Syndrome with Obstructive Sleep Apnea

Apert syndrome is a congenital syndrome characterized by craniosynostosis and craniofacial dysostosis, among other features, and is reported to cause obstructive sleep apnea (OSA) because of upper airway narrowing associated with midfacial dysplasia. We recently encountered a case involving a patient with Apert syndrome complicated by OSA who began to receive continuous positive airway pressure (CPAP) therapy at the age of 4. OSA resolved after maxillofacial surgery performed at the age of 11, and CPAP was eventually withdrawn. In pediatric patients with maxillofacial dysplasia complicated by OSA, a long-term treatment plan including CPAP in addition to maxillofacial plastic and reconstructive surgery should be considered in view of the effects of OSA on growth.