Craniosténoses : résultats fonctionnels et morphologiques post-opératoires

Clinical signs, interventions, and treatment course of three different treatment protocols in patients with Crouzon syndrome with acanthosis nigricans

OBJECTIVE

Crouzon syndrome with acanthosis nigricans (CAN) is a rare and clinically complex subtype of Crouzon syndrome. At three craniofacial centers, this multicenter study was undertaken to assess clinical signs in relation to the required interventions and treatment course in patients with CAN.

METHODS

A retrospective cohort study of CAN was performed to obtain information about the clinical treatment course of these patients. Three centers participated: Erasmus Medical Centre, Rotterdam, the Netherlands; John Radcliffe Hospital, Oxford, United Kingdom; and Hôpital Necker-Enfants Malades, Paris, France.

RESULTS

Nineteen patients (5 males, 14 females) were included in the study. All children were operated on, with a mean of 2.2 surgeries per patient (range 1-6). Overall, the following procedures were performed: 23 vault expansions, 10 monobloc corrections, 6 midface surgeries, 11 foramen magnum decompressions, 29 CSF-diverting surgeries, 23 shunt-related interventions, and 6 endoscopic third ventriculostomies, 3 of which subsequently required a shunt.

CONCLUSIONS

This study demonstrates that patients with the mutation c.1172C>A (p.Ala391Glu) in the FGFR3 gene have a severe disease trajectory, requiring multiple surgical procedures. The timing and order of interventions have changed among patients and centers. It was not possible to differentiate the effect of a more severe clinical presentation from the effect of treatment order on outcome.

The metopic suture: Natural history

The metopic suture (MS) is one of the main sutures of the calvaria; premature closure is responsible for trigonocephaly, while persistence (metopism) is considered a normal variant. The ages of onset and completion of MS closure and prevalence of metopism in normal children are poorly documented. We studied the pattern of MS closure on 3D-CT scans of 477 children admitted for head trauma since 2012. We also studied the prevalence of trigonocephaly and the sex ratio in our clinical series of patients with all types of synostosis diagnosed during the last 4 decades. In the majority of children, MS closure started at 4 months and was complete at 9 months. The prevalence of metopism was stable after 1 year of age, at 5.1%; it was more than twice as frequent in girls (F/M ratio 2.1, non-significant). Our trigonocephaly series and the literature show a steady increase in prevalence over recent decades. During the same period, the prevalence of metopism decreased steadily. Data from comparative anatomy and paleoanthropology suggest that postnatal MS persistence in our species results from the risk of dystocia caused by the closed pelvis associated with bipedalism. The increasing incidence of trigonocephaly appears to parallel the fall in prevalence of metopism. The increasing use of cesarean section may have eliminated a potent selection factor in favor of postnatal persistence of the MS.

Nasal soft-tissue and vault deviation in unicoronal synostosis

BACKGROUND

Unicoronal synostosis (UCS) results in nasal root deviation toward the fused side of the face, resulting in an apparent nasal dorsal deviation to the non-fused side. The impact of the altered radix position on the osteocartilaginous vault and nasal soft tissue has not been analyzed. The purpose of this study is to morphometrically assess the nasal structure and deviation in UCS. We hypothesize the proximal etiology exerts an impact on the distal nasal form, compared to controls.

METHODS

Demographic data were tabulated and computed tomographic information recorded. Three-dimensional reconstruction was created and analyzed digitally (using Surgi Case). Morphometric landmarks were determined and used to perform measurements on the nasal soft tissue and osseous skull surface to evaluate nasal deviation within a midsaggital plane (MSP).

RESULTS

Forty three-dimensional CT scans of 20 UCS patients and 20 control subjects were analyzed. The deviation angle of the nose to the non-fused side was 6.6 ± 2.9° in the bony layer. In the soft-tissue layer, the deviation angle of the nasal dorsum line to the non-fused side was 5.4 ± 3.4°. The tip of the nose showed a significant deviation to the non-fused side (2.2 ± 1.2 mm). Paired landmarks (alares, inferior lateral nostril bases) related to the MSP showed a greater distance on the non-fused side. Paired landmarks related to an intrinsic nasal midline (Nsup-ANS; tip-columella line (TCL)) did not show any significant differences.

CONCLUSION

UCS confers osteocartilaginous and soft-tissue nasal deviation, with the distal nose toward the non-fused side. The nasal root inclination underpins this asymmetry across the midsaggital reference plane. However, the nose in isolation exhibits balanced side-side proportions.

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.

Craniofacial growth in patients with FGFR3Pro250Arg mutation after fronto-orbital advancement in infancy

BACKGROUND

The facial features of children with FGFR3Pro250Arg mutation (Muenke syndrome) differ from those with the other eponymous craniosynostotic disorders. We documented midfacial growth and position of the forehead after fronto-orbital advancement (FOA) in patients with the FGFR3 mutation.

METHODS

We retrospectively reviewed all patients who had an FGFR3Pro250Arg mutation and craniosynostosis. Only patients who had FOA in infancy or early childhood were included. The clinical records were evaluated for type of sutural fusion; midfacial hypoplasia and other clinical data, including age at operation; type of procedures and fixation (wire vs resorbable plate); frequency of frontal readvancement, forehead augmentation, midfacial advancement; and complications. Preoperative and postoperative sagittal orbital-globe relationship was measured by direct anthropometry. Outcome of FOA was graded according to the Whittaker classification as category I, no revision; category II, minor revisions, that is, foreheadplasty; category III, alternative bony work; category IV; redo of initial procedure (ie, secondary FOA). Midfacial position was determined by clinical examination and lateral cephalometry.

RESULTS

A total of 21 study patients with Muenke syndrome (8 males and 13 females) were analyzed. The types of craniosynostosis were bilateral coronal (n=15), of which 3 also had concurrent sagittal fusion, and unilateral coronal (n=5). Two patients had early endoscopic suturectomy, but later required FOA. Mean age at FOA was 22.9 months (range, 3-128 months). Secondary FOA was necessary in 40% of patients (n=8), and secondary foreheadplasty in 25% (n=5) of patients. No frontal revisions were needed in the remaining 35% of patients (n=7). Mean age at initial FOA was significantly younger in the group requiring repeat FOA or foreheadplasty compared with patients who did not require revision (P<0.05). Location of synostosis, type of fixation, and bone grafting did not significantly affect the need for revision. Only 30% (n=6) of patients developed midfacial retrusion.

CONCLUSIONS

The frequency of frontal revision in patients with Muenke syndrome who had FOA in infancy and early childhood is lower than previously reported. Age at forehead advancement inversely correlated with the incidence of relapse and need for secondary frontal procedures. Midfacial retrusion is relatively uncommon in FGFR3Pro250Arg patients.

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.

Vestibular orientation for craniofacial surgery: application to the management of unicoronal synostosis

BACKGROUND

Standardized cephalometric measurements are necessary to compare skulls of different ages and sizes, in normal and diseased subjects, and in different species. In diseases involving the skull base, classical cephalometry is often impossible because the cranial landmarks are modified. In vestibular orientation (VO), the plane of the lateral semicircular canal (LSCC) of the inner ear, which has a constant relation to gravity, defines the horizontal plane of reference. Defining a reference plane independent of external landmarks is especially important in unicoronal craniosynostosis (UCCS), because the skull base is asymmetrical.

AIM OF THE STUDY

To illustrate the interest of VO in clinical practice, we report on our experience with VO-based correction of UCCS.

MATERIALS AND METHODS

Since 1992, we have used VO-3D computed tomography scanner for surgical planning of all patients with UCCS, measuring the required correction as the discrepancy between the theoretical and the observed midline.

RESULTS

Thirty-eight children were operated under the age of 2 years for UCCS and evaluated after a mean follow-up of 66 months. Thirty-two (84%) were considered perfect, four (11%) had mild imperfection not requiring reoperation, and two (5%) required reoperation because of progressive craniosynostosis involving the sagittal suture. Good surgical results were obtained when the orbits were correctly oriented relative to the plane of the LSCC.

CONCLUSIONS

VO is a useful reference system for the evaluation and surgical planning of UCCS. We hypothesize that the mismatch between the visual and labyrinthic sensorial inputs plays a role in the pathophysiology of UCCS.