[The treatment of craniosynostosis: indications and techniques]

Evaluating mechanical benefit of wedge osteotomies in endoscopic surgery for sagittal synostosis using patient-specific 3D-printed models

PURPOSE

Endoscopically assisted sagittal strip craniotomy with subsequent cranial orthosis is a frequently used surgical approach for non-syndromic sagittal synostosis. Originally, this technique involved a wide sagittal strip craniectomy with bilateral wedge osteotomies. More recent studies suggest omitting wedge osteotomies, achieving similar outcomes. The controversy surrounding wedge osteotomies and our efforts to refine our technique led us to create models and evaluate the mechanical impact of wedge osteotomies.

METHODS

We conducted a 3D-print study involving preoperative CT scans of non-syndromic scaphocephaly patients undergoing minimally invasive-assisted remodelation (MEAR) surgery. The sagittal strip collected during surgery underwent thickness measurement, along with a 3-point bending test. These results were used to determine printing parameters for accurately replicating the skull model. Model testing simulated gravitational forces during the postoperative course and assessed lateral expansion under various wedge osteotomy conditions.

RESULTS

The median sagittal strip thickness was 2.00 mm (range 1.35-3.46 mm) and significantly positively correlated (p = 0.037) with the median force (21.05 N) of the 3-point bending test. Model testing involving 40 models demonstrated that biparietal wedge osteotomies significantly reduced the force required for lateral bone shift, with a trend up to 5-cm-long cuts (p = 0.007). Additional cuts beyond this length or adding the occipital cut did not provide further significant advantage (p = 0.1643; p = 9.6381).

CONCLUSION

Biparietal wedge osteotomies reduce the force needed for lateral expansion, provide circumstances for accelerated head shape correction, and potentially reduce the duration of cranial orthosis therapy.

Complex Craniosynostosis in Pitt-Hopkins Syndrome: Case Report in Twins

INTRODUCTION

Pitt-Hopkins syndrome (PTHS) is a rare genetic syndrome associated with neurodevelopmental disorders and craniofacial dysmorphisms caused by variations in the TCF4 transition factor. The aim of this article was to report the case of two twin infants diagnosed with PTHS, confirmed by the identification of a heterozygous pathogenic variant in the TCF4 gene through DNA extracted from a buccal swab.

CASE PRESENTATION

Both infants presented with craniofacial asymmetry with a metopic crest and cranial deformity. During the diagnostic investigation, computed tomography with three-dimensional reconstruction of the skull showed premature fusion of the left coronal and metopic sutures in both twins. They underwent craniofacial reconstruction at the 9th month of age using a combination of techniques. The postoperative outcomes were satisfactory in both cases.

CONCLUSION

To the best of our knowledge, this is the first case report to describe the occurrence of complex craniosynostosis (CCS) in children with PTHS. Further studies are needed to determine whether the co-occurrence of PTHS and CCS described here indicates an association or is explained by chance.

Paediatric skull growth models: A systematic review of applications to normal skulls and craniosynostoses

INTRODUCTION

Craniosynostoses affect 1/2000 births and their incidence is currently increasing. Without surgery, craniosynostosis can lead to neurological issues due to restrained brain growth and social stigma due to abnormal head shapes. Understanding growth patterns is essential to develop surgical planning approaches and predict short- and long-term post-operative results. Here we provide a systematic review of normal and pathological cranial vault growth models.

MATERIAL AND METHODS

The systematic review of the literature identified descriptive and comprehensive skull growth models with the following criteria: full text articles dedicated to the skull vault of children under 2 years of age, without focus on molecular and cellular mechanisms. Models were analysed based on initial geometry, numerical method, age determination method and validation process.

RESULTS

A total of 14 articles including 17 models was reviewed. Four descriptive models were assessed, including 3 models using statistical analyses and 1 based on deformational methods. Thirteen comprehensive models were assessed including 7 finite element models and 6 diffusion models. Results from the current literature showed that successful models combined analyses of cranial vault shape and suture bone formation.

DISCUSSION

Growth modelling is central when assessing craniofacial architecture in young patients and will be a key factor in the development of future customized treatment strategies. Recurrent technical difficulties were encountered by most authors when generalizing a specific craniosynostosis model to all types of craniosynostoses, when assessing the role of the brain and when attempting to relate the age with different stages of growth.

Frontofacial Monobloc Advancement With Internal Distraction: Surgical Technique and Osteotomy Guide

BACKGROUND

Craniosynostosis are cranial deformities resulting from the early closure of 1 or more sutures. Concomitant facial changes are complex and usually result from the involvement of multiple sutures, which may lead to restriction of cranial growth and brain expansion, ocular compression, and breathing difficulties. Surgical techniques to correct syndromic craniosynostosis have improved over time, considerably reducing the rate of complications of this procedure.

OBJECTIVE

To describe in detail (step-by-step) and with pertinent anatomic considerations the technique of monobloc frontofacial advancement using internal distractors.

METHODS

We describe the monobloc frontofacial advancement technique with the use of internal distractors, which we use in patients with primary syndromic craniosynostosis (Apert, Crouzon, and Pfeiffer) who have major facial hypoplasia and secondary respiratory repercussions. To illustrate this technique, the procedure was performed in 2 cranial models: an adult artificial acrylic skull of normal morphology for better evidence of anatomic repairs and a 3-dimensional printed infant skull from a tomography file obtained from a child diagnosed with Apert syndrome.

RESULTS

The benefits of osteogenic distraction and better surgical timing for each procedure are presented. We presented the changes and details of osteotomies performed during the procedure, as well as anatomic details and care regarding the pterygomaxillary dysjunction.

CONCLUSION

Monobloc frontofacial distraction is a procedure with widely demonstrated aesthetic and functional results, and this detailed step-by-step description may improve familiarity with the anatomic landmarks of the procedure and provide a better dynamic understanding of the distraction process.

Single sagittal craniosynostosis surgical treatment with the "Peau d́ours" technique. Single-center experience in Mexico

Scaphocephaly (SC) is defined as an elongation of the anteroposterior axis of the skull resulting from the abnormal fusion of the sagittal suture. This study describes the "Peau d'ours" technique and results for correcting SC. We conducted a consecutive and retrospective analysis of patients treated from 2011 to 2016. We evaluated the gender, age, and surgical outcomes. A total of 53 patients were enrolled with a mean age of 19 months old. The advantages of this technique are healthy coronal and lambdoid suture preservation and symmetrical parietal bone flap opening. This technique is safe and simple to reproduce, allowing good surgical outcomes with a low incidence of secondary craniosynostosis. This technique is ideal for patients older than six months old.

Secondary Raised Intracranial Pressure After Cranial Vault Remodeling for Isolated Sagittal Craniosynostosis

ABSTRACT

The management of sagittal craniosynostosis has evolved over the decades as teams seek to refine their surgical approaches to idealize head shape with the least possible morbidity. Here, the authors identify the incidence of raised intracranial pressure (ICP) and its risk factors, requiring secondary surgical intervention after cranial vault remodeling (CVR) procedure at a single tertiary referral craniofacial unit. A retrospective case-control study was performed on the patients with isolated non-syndromic sagittal craniosynostosis. All patients who underwent CVR in our unit and had a minimum of 1.5 years follow-up were included. One hundred and eighty-four patients (134 male and 50 female) who underwent primary CVR surgery for isolated sagittal craniosynostosis were included. Thirteen patients (7.07%) had clinical evidence of late raised ICP resulting in repeat CVR procedures. Higher incidence of raised ICP in patients who had primary surgery before 6 months than after or at 6 months of age (P = 0.001). There were 23.5%, 5.6%, 3.2%, and 1.9% of secondary raised ICP patients who underwent the primary surgery between 1999-2004, 2005-2010, 2011-2015 and 2016-2018, respectively (P = 0.024). The risk of secondary raised ICP was higher in patients with isolated sagittal craniosynostosis whose primary surgery occurred before the age of 6 months (two times more likely). More extensive CVR can be performed safely in sagittal synostosis with promising outcomes. The late presentation with raised ICP reinforces the importance of long-term multidisciplinary protocol-based follow-up.

Is reverse frontal cranioplasty eligible for the correction of both the forehead deformities and the intracranial hypertension in craniosynostosis? Comparison of the preoperative and postoperative intracranial volumes

BACKGROUND

This study aimed to describe the surgical technique of reverse frontal cranioplasty (RFC), the aesthetical modification as well as the modification of intracranial volume (ICV) to assess its potential eligibility for the treatment of the intracranial hypertension (IH).

MATERIALS AND METHODS

A retrospective monocentric study included the patients with a history of craniosynostosis with a forehead deformity who underwent RFC. A subjective outcome questionnaire (SOQ) was conducted with each patient or their parent to determine their level of satisfaction after RFC. Pre- and postoperative computed tomography (CT) scans were analyzed and compared to investigate the ICV change and fronto-nasal angle.

RESULTS

Eleven patients were included in the study (6 female and 5 male) with a mean age of 10.9 years old (range 3-23 years) and an average follow-up of 4.5 years (1-11 years). All patients responded to the questionnaire with a high level of overall satisfaction (mean 9.1/10). The mean preoperative FNA was 134° ± 5° while the mean postoperative angle was 126.4° ± 6, corresponding to an average decrease of 7.6° (95% CI, 4.0-11.2°; p < 0.001). One patient with preoperative IH had a clinical recurrence during the follow-up. The ICV was significantly higher after the surgery (p < 0.0001), with an average increase of 3.2% (95% CI, 2.3-4.1%).

CONCLUSION

Reverse (RFC) is a useful technique for the correction of the frontal malformations related to craniosynostosis, such as a sloping forehead and/or a lack of the supraorbital projection. Regarding the limited gain of intracranial volume (ICV), it should not be used alone as primary cranial expansion surgery for craniosynostosis with intracranial hypertension (IH).

Role of distraction osteogenesis in craniomaxillofacial surgery

In the field of orthopedic surgery, distraction osteogenesis (DO) is well known for limb lengthening procedures or secondary corrective surgery in the fracture treatment of the extremities. The principle of gradual expansion of bone and surrounding soft tissues as originally described by G.A. Ilizarov is also applicable to the craniofacial skeleton when growth deficiency is present, and the patients affected by craniofacial or dentofacial anomalies may require distraction procedures. The surgical management is comparable. After osteotomy and the mounting of a specific craniomaxillofacial distraction device, active distraction is started after a latency phase of several days, with a distraction rate of up to 1 mm/day until the desired amount of distraction has been achieved. Subsequently, distractors are locked to provide appropriate stability within the distraction zone for callus mineralization during the consolidation phase of 3–6 months, which is followed by a further remodeling of the bony regenerate. After 14 years of clinical application, the role and significance of craniomaxillofacial DO are discussed after reviewing the files of all patients who were treated by craniomaxillofacial distraction procedures.

Surgical guide for the remodelling of the orbito-naso-frontal bandeau in craniosynostosis surgery

INTRODUCTION

Craniosynostoses affecting the forehead sutures can not only cause brain damage, but can also have an esthetic impact, because of the associated orbito-naso-frontal deformations. Reshaping the orbito-naso-frontal bandeau (ONFB) is difficult to appreciate perioperatively and should ideally be customized to each child. The aim of this study was to develop a template to guide the surgeon preoperatively towards an ideal customized remodelling of the ONFB.

MATERIALS AND METHODS

A previous study conducted on computed tomography scans obtained from healthy children allowed us to conclude that the whole ONFB shape could be accurately described just by the distance measured between the fronto-zygomatic sutures (FZD), independently of age and gender. Our customizable template relies on this measurement.

RESULTS

A re-usable template, built around three supports adjustable to a wide range of FZD, was designed using the CAD 3D Rhinoceros^® software and machined in stainless steel 316L. The prototype was used for three children with good preliminary results.

DISCUSSION AND CONCLUSION

The use of a customizable surgical template allows the surgeon to perform accurate and ideal perioperative remodeling of the ONFB in children suffering from craniosynostosis affecting the forehead sutures. Our prototype is currently the only one to be adjustable according to the FZD. The utility of this device will be assessed in a future prospective clinical study.

[Study of the normality of the orbito-naso-frontal bandeau]

INTRODUCTION

Craniosynostoses are cranio-facial malformations affecting about 1/2100 newborns in France. The involvement of anterior sutures (coronal and metopic) leads to orbito-frontal deformities. The treatment calls upon surgery the goal being, on an esthetic point of view, to restore a normal anatomy. The purpose of our work was to establish if some facial and/or frontal measures easy to perform on a CT are correlated to the global shape of the normal orbito-naso-frontal bandeau (ONFB).

MATERIAL AND METHOD

Cranial CTs of 123 consecutive non-malformed children aged between 4 and 12 months were selected in the database of Department of Radiology of the University Hospital of Besançon - France. The CTs were all relocated by rigid transformation in an orthonormal coordinate system. On each of the 123 CTs, 21 reproducible measures representative of the global shape of the ONFB were made. Statistical analyses of these measures were achieved, considering age and gender, in order to determine the correlation between each measure and the ONFB shape.

RESULTS

The only measure statistically correlated to the ONFB shape was the distance between the fronto-zygomatic sutures (FZD). The FZD was independent from age (in an interval of 4 months) and from gender. The 20 other measures did not show any correlation with age or gender.

DISCUSSION

The FZD allows in itself to determine the ONFB global shape. This measure, easily available on a CT, can help the surgeon to perform a customized reshaping of the ONFB. The development of a surgical template using this measure is ongoing.

Skull base morphology in fibroblast growth factor receptor type 2-related faciocraniosynostosis: a descriptive analysis

BACKGROUND

Children with faciocraniosynostosis present skull base abnormalities and may develop hydrocephalus or cerebellar tonsils ectopia (CTE). Several pathophysiological hypotheses were formulated in the past decades to explain these associations. However, no study has described in a genetically homogeneous population with confirmed fibroblast growth factor receptor type 2 (FGFR2) mutation eventual correlations between skull base abnormalities and hydrocephalus or CTE.

OBJECTIVE

To illustrate these features in children <2 years of age with a genetically confirmed FGFR2-related faciocraniosynostosis.

METHODS

We measured the foramen magnum area (FMA) and its sagittal and transversal components: the right, left, and mean area of the jugular foramen; the posterior fossa volume; and the cerebellar volume on preoperative millimetric computed tomography scan slices in 31 children with an FGFR2 mutation (14 with Crouzon syndrome, 11 with Apert syndrome, and 6 with Pfeiffer syndrome). They were compared with 17 children without synostosis. All children were <24 months of age. We correlated all these measures with the presence of hydrocephalus or CTE.

RESULTS

We observed a significantly small FMA in children with Crouzon (P = .03) and in children with Pfeiffer (P = .05) resulting from a reduced sagittal diameter (P = .02 for Crouzon and P = .002 for Pfeiffer). Hydrocephalus was associated with small FMA (P = .02). The jugular foramen area, posterior fossa volume, and cerebellar volume were not associated with hydrocephalus or CTE. Hydrocephalus and CTE were statistically associated (P = .002).

CONCLUSION

Hydrocephalus in FGFR2-related Crouzon and Pfeiffer syndromes is statistically associated with a small FMA. Hydrocephalus is statistically associated with CTE.

[Our experience about the use of resorbable plates in the treatment of craniostenosis]

INTRODUCTION

The use of resorbable plates increases for craniosynostosis surgery. This material, based on polymere (PLA, PGA) can replace steel wire and non resorbable plates. A few studies present surgical results about the use of this material with a long follow-up. We present our ten years experience of using resorbable material for craniosynostosis treatment in children.

METHODS

Between 2002 and 2012, we operated 283 craniosynostosis (98 scaphocephalies, 55 trigonocephalies, 79 plagiocephalies et 51 craniofaciostenoses). Among these surgeries, 211 were realized with resorbable material (plates and screws). Different criteria were observed: the esthetic result, the infection rate, the re-intervention, the bone defects and the inflammatory granuloma.

RESULTS

Among the 211 craniosynostosis, we found 62 plagiocephalies, 66 scaphocephalies, 50 trigonocephalies, 33 craniofaciostenoses. All the reconstructions were realized with the same resorbable material (Macropore by Medtronic). The rate of complications was low: one scar infection without participation of material for two patients (0.9%), a pseudo-meningocele for two patients (0.9%), epilepsy for four children (1.8%) and bone defect for 15 (7%). We observed no granuloma for these patients.

CONCLUSION

Our experience of ten years using resorbable material is very satisfactory. This material permits to realize solid and esthetic reconstructions with a low rate of infection without dangerous reaction for children in young age.

[Some features of the nose in craniofacial malformations]

In craniofacial malformations, the nose is variably affected: in its location, its shape or by lack of development. In this short chapter, some of the common problems encountered by the specialized teams are summarized. Craniofacial astronomies can modify the skeleton of the nose during growth, sometime at an early age. However, most rhinoplasties are performed at adulthood. The nasal pyramid may present deformations that produce functional and aesthetics impairment that should be treated when necessary. Respiratory problems should be recognized as early as possible and treated in priority.

Mesh-based method for measuring intracranial volume in patients with craniosynostosis

PURPOSE

Craniosynostosis may lead to reduced intracranial volume (ICV) and disturb normal brain growth and development. Thus, ICV is an important parameter with respect to the surgical outcome. Current methods for ICV determination from computed tomography (CT) images have drawbacks. The aim of this study was to investigate the performance of the novel mesh-based method (MBM) for ICV determination with craniosynostosis patients.

METHODS

Twenty-two patients operated on for scaphocephaly were included in this study. ICVs from preoperative, one-week postoperative, and one-year postoperative CT images were measured with MBM. The level of agreement with the manual segmentation method (MSM) was determined for the measurements of preoperative and one-year postoperative datasets. Repeatability was determined with re-measurements of six datasets. Measurement time was recorded for MBM.

RESULTS

Mean [Formula: see text] preoperative ICV values were 895.0 [Formula: see text] 153.1 [Formula: see text] and 896.4 [Formula: see text] 147.2 [Formula: see text] as measured with MBM and MSM, respectively. Corresponding one-year postoperative values were 1,238.3 [Formula: see text] 118.7 [Formula: see text] and 1,250.1 [Formula: see text] 117.5 [Formula: see text]. The MBM allowed ICV determination from one-week postoperative datasets. Measurement time with MBM was 4 CONCLUSIONS: MBM is an efficient method for determining the ICV of craniosynostosis patients, allowing the measurement of skulls with bony defects. The repeatability and short measurement time of MBM are attributable to the user interference and assessment of the measurement process.

Scaphocephaly correction with retrocoronal and prelambdoid craniotomies (Renier's "H" technique)

The aim of this paper is to describe the surgical technique, originally devised by Dr. Renier which is currently used to treat children with scaphocephaly under 6 months of age at the Craniofacial Unit of Hopital Necker Enfants Malades (French National Referral Center for Faciocraniosynostosis), focusing on its advantages and limitations.

Anterior fronto-orbital remodeling for trigonocephay

INTRODUCTION

Trigonocephaly secondary to the premature fusion of the metopic synostosis is associated to a risk of cerebral compression and several craniofacial morphological alterations. Numerous surgical techniques have been proposed. They all carry a risk of secondary temporal hollowing

PURPOSE

The aim of this paper is to describe the surgical technique used for trigonocephaly at the craniofacial unit of Hopital Necker Enfants Malades (French National Referral Center for Faciocraniosynostosis) focusing on its advantages and limitations. Resorbable osteosynthesis should be part of the current techniques.

Evaluation and management of nonsyndromic craniosynostosis

Craniosynostosis (craniostenosis) is premature fusion of the sutures of the cranial vault. Several factors can affect the growth of the cranial vault during embryonic life and after birth, leading to different types of craniosynostosis; these can be classified on the basis of the specific sutures that are fused. Prognosis is improved by early diagnosis, and it is important to establish the correct approach to these patients on the basis of clinical and neuroradiological investigation. The first priority is to identify the type of craniosynostosis and to distinguish between the types that require surgical intervention and those that do not. We report on the different forms of nonsyndromic craniosynostosis, their clinical and neuroradiological diagnoses, and surgical strategies.

CONCLUSION

The aim of this review is to provide to paediatricians a correct diagnostic approach and management of children affected from nonsyndromic craniosynostosis, for which a careful physical, ophthalmological and neurological examination is fundamental, whereas brain Computed tomography and magnetic resonance imaging are necessary for patients in which the diagnosis is uncertain or for cases of syndromic craniosynostosis.

Necrotizing soft tissue infection of the scalp after fronto-facial advancement by internal distraction in a 7-year old girl with Gorlin-Chaudhry-Moss syndrome--a case report

In 1960, Gorlin, Chaudhry and Moss described a syndrome consisting of craniofacial dysostosis in association with hypertrichosis, cardiac, genital, dental and ocular anomalies. Diagnosis is based on typical clinical findings and cannot be performed by molecular genetic analysis until now. There is little in the clinical literature concerning this rare craniofacial syndrome. For functional and psychosocial reasons, surgical correction of the complex craniofacial malformation in a 7-year old Hungarian girl with Gorlin-Chaudhry-Moss syndrome was performed by fronto-facial advancement using internal distraction devices. Postoperatively necrotizing soft tissue infection of the scalp developed leading to termination of the distraction process ahead of schedule and requiring aggressive surgical management. Typical physiological and clinical characteristics were observed both during the initial craniofacial correction as well as during the management of the infectious complication suggesting that the linking of different conditions (surgical trauma plus the selection of toxic microorganisms) has caused tissue destruction rather than the syndromal disorder or the surgical technique of distraction osteogenesis. Although skeletal improvement was achieved residual damage from the infectious complication must be considered as severe.

Antley-Bixler-syndrome--staged management of craniofacial malformations from birth to adolescence--a case report

In 1975 Antley and Bixler described an unusual syndromal disorder consisting of complex craniosynostosis with midfacial hypoplasia, dysplasia of ears and nose, radiohumeral synostosis, congenital fractures of the femur and upper airway impairment in a newborn. Additional urogenital and cardiac malformations can be associated however diagnosis is based on a characteristic craniofacial deformity in association with humeroradial synostosis. Complex disturbance of craniofacial growth due to premature synostoses of the cranial base and vault results in a characteristic phenotype. Steroidogenesis due to intrinsic or extrinsic disturbance by maternal fluconazole ingestion during early pregnancy may be impaired. The mode of inheritance is supposed to be autosomal recessive. Mutations in the fibroblast growth factor receptor 2 (FGFR2) as well as mutations in the cytochrome P450 oxidoreductase (OR) gene have been verified. Like in other craniofacial dysostosis syndromes malformation of neuro- and viscerocranium is complex and requires a staged age- and growth-related interdisciplinary management with respect to the individual situation. This case report of a female patient born in 1994 suffering from that rare syndrome describes the interdisciplinary long-term management in one craniofacial centre over 16 years from birth to adolescence.