Scaphocephaly: Part I

Novel Method of Lateral Vault Modification in Scaphocephaly

BACKGROUND

Scaphocephaly is the commonest from of craniosynostosis. There are several surgical methods to correct this and is influenced by the areas affected. A common thread in any of these corrections is an attempt to increase the biparietal diameter by modifying the lateral vault panel (LVP). A simple and novel method is proposed.

MATERIALS AND METHOD

The records of all patients undergoing scaphocephaly correction in the craniofacial unit at the institution were reviewed from 2003 to 2019. There were 106 patients, 57 males, and 49 females. The age ranged from 6 months to 5 years with a mean of 11 months. The method of vault remodeling was LVP only in 36 (34%), subtotal vault remodeling in 59 (56%), and total vault remodeling in 11 (10%). All 106 patients underwent LVP remodeling as part of the procedure. One or 2 wedge excisions was performed to increase the curvature of the LVP and this panel was fixed on the outside of the temporal squame bone.

RESULTS

The patients were followed up for a minimum of 1 year. Satisfactory results were obtained. The mean preoperative cephalic index was 64% and the mean postoperative index was 75%. There were minor complications such as screw visibility in a few patients.

CONCLUSIONS

Wedge excisions of the LVP is a simple and effective maneuver that can be used as strategy when performing scaphocephaly correction.

Does Coronal Suturectomies and Occipital Barrel Staves Make a Difference in Early Reconstruction for Sagittal Craniosynostosis?

BACKGROUND

Various surgical methods are used for early treatment of nonsyndromic sagittal craniosynostosis. The craniofacial centers in Uppsala and Helsinki fundamentally both use the H-Craniectomy: Renier's technique. However, the Helsinki group systematically adds coronal suturectomies to prevent secondary coronal synostosis and posterior barrel staves to address posterior bulleting. The effects of these additions in early treatment of sagittal craniosynostosis are currently unknown.

METHODS

Thirty-six patients from Uppsala and 27 patients from Helsinki were included in the study. Clinical data and computed tomography scans were retrieved for all patients.

RESULTS

The Helsinki patients had a smaller preoperative Cranial index (CI) (65 vs 72) and a smaller preoperative width (10.1 vs 11.2). There was no difference in postoperative CI, corresponding to a difference in change in CI. Regression analysis indicated that the larger change in CI in the Helsinki group was mainly due to a lower preoperative CI allowing for a larger normalization. The Helsinki patients had less growth in length (1.5 vs 2.1 cm) and more growth in width (2.3 vs 1.9 cm). There were no differences in head circumference or surgical complications. Secondary coronal synostosis was present in 43% of the Uppsala group at 3 years of age, while calvarial defects located at sites of previous coronal suturectomies and posterior barrel staving were seen in the Helsinki group 1 year postoperatively.

CONCLUSIONS

Lower preoperative CI appears to be the main factor in determining the amount of normalization in CI. Prophylactic coronal suturectomies do not seem to benefit preservation of coronal growth function since the modification correlates to less sagittal growth and more growth in width.

Anthropometric changes in the skull base in children with sagittal craniosynostosis submitted to surgical correction

PURPOSE

Studies have examined the impact of fusion of the sagittal suture in the skull base while others have evaluated the growth of the skull base before and after surgery. This study aims to perform the anthropometric measures of the skull base in children with scaphocephaly to evaluate the influence of surgical repair in the remodeling of the skull base and anthropometric measures.

METHODS

Twenty-one children with diagnosis of scaphocephaly were operated between April 2007 and October 2008, and anthropometric measures at the skull base were performed before and after a year of surgery. The measures were the cranial index (CI), distance between the crista galli and tuberculum sellar (CG-TS), distance between the crista galli and the internal auditory meatus (CG-IAM), distance between the oval foramen (OF-OF), distance between the internal auditory meatus (IAM-IAM), the angle of the skull base (Â1), and the angle between the nasion, center of sella, and basion (Â2).

RESULTS

There was a normalization of the CI in all children, confirming an appropriate cranial remodeling. The CG-TS measure evaluated the anterior skull base, with proportional growth of 12.5%. The mediolateral growth was observed by the increase of OF-OF measures by 8.5% and IAM-IAM by 9.5%. The CG-TS measure grew by 7.2%. There was no statistical difference in the angles analyzed.

CONCLUSION

Surgical treatment of scaphocephaly led to remodeling of the skull base, confirmed by the changes of anthropometric measures taken before and after a year of surgery.

Endoscopic Versus Open Total Vault Reconstruction of Sagittal Craniosynostosis

: Sagittal craniosynostosis is the most common form of congenital cranial deformity. Surgical interventions are performed either open or endoscopic. Advancements in minimally invasive surgery have enabled the development of the endoscopic suturectomy technique. This is contrasted to the traditional open cranial vault reconstruction. There is a paucity of data comparing the head shape changes from both techniques. This study aims to compare the morphological outcome of endoscopic suturectomy versus total cranial vault reconstruction.

METHODS

This is a retrospective comparative study involving 55 cases of sagittal craniosynostosis, 37 of which has open total cranial vault reconstruction and 18 had endoscopic suturectomy procedure. Preoperative and postoperative 3D photographs of both groups were analyzed and compared. The change in correction between preoperative and postoperative state was measured against a crowd-driven standard for acceptable head shape.

RESULTS

Total cranial vault had higher percentage change between pre and postoperative cranial index than endoscopic suturectomy (14.7% versus 7.7%, P = 0.003). However, both techniques were able to achieve the minimum standard of 70% correction (TCV 107.5%, ES 100.4%, P = 0.02).

CONCLUSION

Total cranial vault and endoscopic suturectomy are effective in correcting scaphocephaly among children with sagittal craniosynostosis. Additionally, both techniques are able to achieve a percentage correction that exceeds the 70% benchmark established by the lay public.

Public Perception of a Normal Head Shape in Children With Sagittal Craniosynostosis

: A question that remains unanswered is at what level of surgical correction does the public perceive a head shape to be "normal" or "acceptable?" For most cases of non-syndromic asymptomatic craniosynostosis, the parents desire for surgical correction is to improve the cosmetic appearance of head shape. At the time of this writing, the intraoperative surgeons' perspective of what constitutes an acceptable head shape is the target for surgical correction. In introducing an improved objectively cosmetic goal, an appropriate outcome measure would be to assess what the general public considers a normal or acceptable head shape in children with craniosynostosis.

METHOD

Twenty-two unique images were presented via an online crowdsourcing survey of a severe case of non-syndromic sagittal craniosynosis gradually corrected to an age and gender matched normalized head shape. Participants were recruited via the Sick Kids Twitter account. Participants were invited to rate the head shapes as "normal" or "abnormal."

RESULTS

The 538 participants completed the online survey. Participants were able to reliably and consistently identify normal and abnormal head shapes with a Kappa Score >0.775. Furthermore, participants indicated that a correction of 70% is required in order for the cranial deformity to be regarded as "normal." This threshold closely reflects a normal Cranial Index, which is a widely used morphometric outcome in craniosynostosis.

CONCLUSION

Crowdsourcing provides an ideal method for capturing the general population's perspective on what constitutes a normal and acceptable head shape in children with sagittal craniosynostosis. Laypersons are able to reliably and consistently distinguish cranial deformities from a "normal" head shape. The public indicates a threshold correction of 70% in sagittal craniosynosis to regard it as a "normal" head shape.

Secondary Coronal Synostosis After Early Surgery for Sagittal Craniosynostosis: Implications for Cranial Growth

ABSTRACT

Secondary Coronal Synostosis (SCS) in patients operated for non-syndromic Sagittal Craniosynostosis is a postoperative phenomenon with unclear implications. The aim of this study was to investigate whether SCS is a negative or a benign occurrence in the postoperative course. The authors hypothesized that SCS is related to reduced cranial growth and intracranial hypertension. Thirty-one patients operated for SC at an early age with the H-craniectomy technique were included in the study. Associations between SCS and cranial shape, growth, and signs of intracranial hypertension were analyzed. Intracranial volume distribution was assessed by measuring partial intracranial volumes defined by skull base landmarks. A total of 12/31 patients developed SCS during the postoperative course. The presence of SCS was associated with a higher prevalence of gyral impressions and a larger normalization of Cranial Index due to less growth in the anteroposterior plane. The SCS group had a smaller postoperative intracranial volume due to less posterior intracranial volume as well as less growth in head circumference. Whether this is a growth restriction caused by the SCS or a secondary effect of less primary brain growth remains to be determined. However, the correlation between SCS, less cranial growth and gyral impressions does imply that SCS should be taken into consideration during clinical follow-up as a potentially adverse event.

Upward vectors for osteogenic distraction treatment in secondary chronic intracranial hypertension in children undergoing scaphocephaly surgery: 2 cases reported

The occurrence of secondary synostosis of coronal sutures at distance from H-craniectomy surgery for scaphocephaly concerns about 10% of children. Intracranial hypertension in these children remains exceptional but generally requires a surgical reoperation. Two children aged 3 and 5- months- old had been operated for scaphocephaly by H-craniectomy in two different hospital centers. Their clinical follow-up described a partial persistence of dolichocephalic deformity and an impression of parietal stenosis. During their growth, chronic headaches appeared with a complaint expressed at the ages of 4 and 5 years. In both cases, ophthalmic examination revealed significant bilateral papillary edema without loss of visual acuity. The imaging assessment (CT-scan and MRI) showed the absence of Chiari malformation and venous abnormality. For both, there was a compression image of the parietal lobes in relation to the persistence of a temporoparietal synostosis. An osteogenic parietal distraction permitted a volumetric brain expansion consecutive to the skull and meninges remodeling in only 6 months, associated with a leap forward acquisition, a normalization of the ophthalmic examination, and a complete loss of headaches. In conclusion, this new approach could be used in the case of chronic intracranial hypertension consecutive to a secondary parietal synostosis after a scaphocephaly surgery.

The value of three-dimensional photogrammetry in isolated sagittal synostosis: Impact of age and surgical technique on intracranial volume and cephalic index─a retrospective cohort study

PURPOSE

The aim of this study was to compare the outcome of intracranial volume (ICV) and cephalic index (CI) between two different techniques for surgical therapy of sagittal synostosis.

MATERIAL AND METHODS

Between 2011 and 2015, all patients scheduled for surgical therapy of sagittal synostosis were consecutively enrolled. All patients younger than 6 months underwent early extended strip craniectomy (ESC group), and patients older than 6 months underwent late modified pi-procedure (MPP group). To measure ICV and CI, data acquisition was performed via three-dimensional photogrammetry, 1 day before (T0) and between 10 and 12 weeks after surgery (T1). Results were compared with an age-matched reference group of healthy children. Perioperative parameters, as duration of surgery and the amount of blood loss of both surgical procedures were analyzed.

RESULTS

A total of 85 patients were enrolled. Of the patients, 48 underwent an extended strip craniotomy with parietal osteotomies and biparietal widening and 37 patients underwent a late modified pi-procedure. There was no significant difference between the ESC group and the MPP group regarding the efficacy of improving CI (p > 0.05). Both techniques were able to normalize CI and to improve head shape. ICV was normal compared to age-matched norm-groups with both techniques, pre- and postoperatively. However, duration of the surgical procedure and calculated blood loss were significantly lower in the ESC group (p < 0.05).

CONCLUSION

ESC and MPP were effective techniques to normalize cephalic index (CI) and improve head shape at their recommended time of surgery. Measurement of ICV and CI with 3D photogrammetry is a valid method to objectively evaluate patients before and after surgery without exposing pediatric patients to ionizing radiation.

Statistical shape modelling to aid surgical planning: associations between surgical parameters and head shapes following spring-assisted cranioplasty

PURPOSE

Spring-assisted cranioplasty is performed to correct the long and narrow head shape of children with sagittal synostosis. Such corrective surgery involves osteotomies and the placement of spring-like distractors, which gradually expand to widen the skull until removal about 4 months later. Due to its dynamic nature, associations between surgical parameters and post-operative 3D head shape features are difficult to comprehend. The current study aimed at applying population-based statistical shape modelling to gain insight into how the choice of surgical parameters such as craniotomy size and spring positioning affects post-surgical head shape.

METHODS

Twenty consecutive patients with sagittal synostosis who underwent spring-assisted cranioplasty at Great Ormond Street Hospital for Children (London, UK) were prospectively recruited. Using a nonparametric statistical modelling technique based on mathematical currents, a 3D head shape template was computed from surface head scans of sagittal patients after spring removal. Partial least squares (PLS) regression was employed to quantify and visualise trends of localised head shape changes associated with the surgical parameters recorded during spring insertion: anterior-posterior and lateral craniotomy dimensions, anterior spring position and distance between anterior and posterior springs.

RESULTS

Bivariate correlations between surgical parameters and corresponding PLS shape vectors demonstrated that anterior-posterior (Pearson's [Formula: see text]) and lateral craniotomy dimensions (Spearman's [Formula: see text]), as well as the position of the anterior spring ([Formula: see text]) and the distance between both springs ([Formula: see text]) on average had significant effects on head shapes at the time of spring removal. Such effects were visualised on 3D models.

CONCLUSIONS

Population-based analysis of 3D post-operative medical images via computational statistical modelling tools allowed for detection of novel associations between surgical parameters and head shape features achieved following spring-assisted cranioplasty. The techniques described here could be extended to other cranio-maxillofacial procedures in order to assess post-operative outcomes and ultimately facilitate surgical decision making.

Progressive frontal morphology changes during the first year of a modified Pi procedure for scaphocephaly

PURPOSE

The purpose of this study was to quantify the changes in frontal morphology in patients with scaphocephaly treated with a modified Pi procedure.

METHODS

Consecutive scaphocephalic patients (n = 13) who underwent surgery before 12 months of age that had more than 1 year of follow-up and standard preoperative, 3-month, and 1-year photographs were included. Anthropometric measurements were used to document the craniofacial index. Computerized photogrammetric analyses of five craniofacial angles (bossing angle, nasofrontal angle, angle of facial convexity, and angle of total facial convexity) were also performed.

RESULTS

Comparisons of the preoperative and postoperative direct anthropometric measurements of the cephalic index showed a significant (all p < 0.05) increase in the postoperative period, with no significant differences in early versus late postoperative period comparisons. Comparisons of the preoperative and postoperative computerized photogrammetric measurements of the craniofacial angles showed a significant (all p < 0.05) reduction (bossing angle, angle of facial convexity, and angle of total facial convexity) and increase (nasofrontal angle) in the early and late postoperative periods.

CONCLUSIONS

Frontal morphology significantly changed over the first year of the modified Pi procedure.

Triple square extended osteotomies for treatment of scaphocephaly (Renier's "H" technique modification)

Scaphocephaly is the most common single suture craniosynostosis. Surgical technique has evolved from simple strip craniectomy over π-procedures and vertex craniectomies to extensive cranial remodeling which is preferred procedure nowadays. The purpose of this paper is to present our modification of Renier's standard "H" technique and its preliminary results in detail. Eleven patients with scaphocephaly were surgically treated from January 2011 until January 2014. Only children with isolated sagittal synostosis were included in the study. Our modified Renier's technique reduces the possibility of lesion of superior sagittal sinus, dividing parietal bone in three bone fragments, thus achieving shortening of the scull in AP diameter without detaching the bone from the superior sagittal sinus. The possibility for potential secondary stenosis is minimized using extended V-shaped osteotomies with rounding of the bone edges, as well as making wide neocoronal and neolambdoid sutures. Cosmetic results were estimated as very pleasing immediately after surgery by both the parents and the surgeons in all cases. The majority of patients presented in our study were categorized as Sloan Class 1. Improvement or normalization of the cranial index was accomplished in all patients. No revision surgeries were required during the follow-up. Triple square extended osteotomies technique is a fast, simple, and efficient surgical option for children with sagittal synostosis and can be safely applied in the first months of life in children even under weight of 6 kilos. Preliminary results are encouraging and deserve a longer follow-up and comparative surgical analysis to verify its usefulness in the future.

Frontobiparietal remodeling with or without a widening bridge for sagittal synostosis: comparison of 2 cohorts for aesthetic and functional outcome

OBJECT Various techniques to correct sagittal synostosis have been described. The authors of this study assess the results of 2 techniques for late complete cranial remodeling and test the hypothesis that adding a widening bridge would improve outcome. METHODS In this retrospective study, the authors evaluated patients with nonsyndromic sagittal synostosis-those who underwent frontobiparietal remodeling (FBR) and those who underwent modified FBR (MFBR) involving the introduction of a bony bridge to increase the width of the skull. Outcomes for both groups are described in terms of the aesthetic results assessed on photographs and any changes in the cranial index (CI) and head circumference over time, the presence of papilledema, and complaints of headache. The effect of the surgical technique on CI and head circumference over time was assessed using linear regression analysis, with adjustment for preoperative CI and head circumference. RESULTS Sixty-nine patients with isolated sagittal synostosis were included in this study: 35 underwent MFBR and 34 underwent the original technique of FBR. The mean follow-up period was 7 years. In the 1st year after surgery, mean CI improved by 9% in the FBR group and by 12% in the MFBR group. One year after surgery, CI in the MFBR group was on average 4.7% higher than that in the FBR group (p < 0.001). During follow-up, CI decreased in both groups; however, at all time points CI was significantly higher in the MFBR group than in the FBR group. The impact of surgical technique on CI was less important than the impact of preoperative CI (R(2)= 0.26 vs 0.54), and this applied at all time points during follow-up. Head circumference declined during follow-up in both groups. It was influenced by preoperative head circumference, but not by surgical technique. Aesthetic outcome, prevalence of headache (42%), and papilledema (7%) were comparable in both groups. CONCLUSIONS Adding a widening bridge to late complete remodeling significantly improved CI and helped to prevent CI from decreasing in the long term. This addition did not affect the head circumference growth curve. Despite a mean head circumference remaining at +1 SD, patients continued to develop papilledema postoperatively (7%).

Cephalic index correlates poorly with intracranial volume in non-syndromic scaphocephalic patients

OBJECTIVES

This study aims to compare pre- and postoperative cephalic indexes (CI) with corresponding segmented intracranial volumes (SIV) obtained from volumetric CT in scaphocephalic patients.

METHODS

Twenty-four patients (17 boys) who had undergone cranial vault remodeling due to scaphocephaly were compared from 3D-CT imaging datasets. The mean age of the patients at preoperative CT imaging was 5.5 months, and that at 1-year postoperative imaging, 21.5 months. The mean interval between preoperative CT imaging and surgery was 3.3 months. Pearson's correlation was used to test the correlation of both pre- and postoperative CI with SIV. A paired t test was used to compare differences in the pre- and postoperative mean values of CI and SIV.

RESULTS AND DISCUSSION

CI correlated poorly with intracranial volume both preoperatively (r = 0.274) and postoperatively (r = 0.128). The mean preoperative CI was 65.92 (range 57.99-73.97), and the mean postoperative, CI 70.24 (range 60.23-75.57). The mean preoperative intracranial volume was 877.79 cm(3) (range 638-1,256), and the 1-year postoperative volume, 1,249.04 cm(3) (range 1,039-1,529). The mean values of both CI and SIV increased significantly after surgery. In one patient, the CI in postoperative measurements was smaller, whereas in all patients, the postoperative SIV was larger than the preoperative intracranial volume. The mean percentage increase in CI was 6.6 %, whereas the mean increase in SIV was 43.1 %.

CONCLUSION

Cephalic index correlates poorly with intracranial volume in non-syndromic scaphocephalic patients. For some patients, surgery and growth resulted in only subtle or no change in CI despite a notable increase in intracranial volume.

Surgical treatment of sagittal synostosis by extended strip craniectomy: cranial index, nasofrontal angle, reoperation rate, and a review of the literature

BACKGROUND

Sagittal synostosis is the most common non-syndromic single suture craniosynostosis. Different techniques of surgical correction, including extended strip craniectomy (ESC), have been used to treat this condition. The aim of this study is to evaluate radiologic changes and rate of symptomatic restenosis after ESC in a large group of patients less than 12 months of age with non-syndromic sagittal synostosis.

METHODS

A retrospective study of patients from 1990 to 2012 was performed comparing cranial index (CI) and nasofrontal angle (NFA) before and after surgical correction by ESC. Also, the frequency of subsequent reoperations for symptomatic restricted head growth was determined.

RESULTS

A total of 238 patients underwent ESC. Follow-up information was available for 182 patients. The average age at the time of the operation was 4.5 months and the mean duration of follow-up was 49.6 months. The average post procedure radiologic follow-up (22 patients) was 40.7 months.

CONCLUSIONS

The mean CI increased from 0.68 to 0.75 (p < 0.001) after ESC. Also, mean NFA increased from 127 to 133° (p < 0.001). Five patients (2.7%) required a second operation due to symptomatic cranial growth restriction. Reoperation occurred at an average of 26.5 months after the initial procedure. The most common symptom reported was headache. ESC is effective in treating non-syndromic sagittal synostosis. It significantly improved NFA without the need for direct frontal bone resection or frontal orbital osteotomy and significantly increased CI without adjunctive helmet treatment. Patients should be followed for at least 5 years after surgical correction as symptomatic restenosis, although rare, can occur.

Results of early surgery for sagittal suture synostosis: long-term follow-up and the occurrence of raised intracranial pressure

PURPOSE

Numerous techniques are used to correct sagittal synostosis. Although cosmetic results and operative complications are well documented, little is known about functional outcome. In our institution, the technique for extended strip craniectomy evolved over time. This study compares cosmetic results, complications, and signs of raised intracranial pressure (ICP) between the variants of the extended strip craniectomy.

METHODS

Seventy-nine consecutive patients undergoing early extended strip craniectomy for scaphocephaly (2002-2008) were included. Four techniques were used: A, a simple bilateral parietal flap with out-fracturing of the bone flap; B, C, and D included remodeling of the parietal flap by adding triangular cuts and bending or suturing the resulting fingers. In technique D, the sagittal strip was rotated and fixed between the parietal flaps. Data on head circumference (HC), skull X-ray, and fundoscopy were collected prospectively.

RESULTS

For all patients, the average cranial index (CI) was 74 after 3 months and 72 after 2 years. Although technique D resulted in the best initial improvement, there was no significant percentage increase in CI after 24 months between the four techniques. Postoperatively, 9 % of the patients developed papilledema, 42 % developed a fontanel bulge, and 57 % had diminished HC. Four patients were reoperated on because of raised ICP.

CONCLUSIONS

Postoperative CI is mainly determined by preoperative CI and hardly affected by type of extended strip craniectomy. Signs of raised ICP occurred more frequently than expected, therefore structural follow-up is required to detect such signs. Technique and timing of surgery should aim at creating sufficient intracranial volume.

Scaphocephaly and cranial vault reconstruction: Renier's 'H' technique

BACKGROUND

Resulting from an early fusion of the sagittal suture, scaphocephaly (SC) is the most frequent form of all craniosynostosis and represents 40-60% of all cases. The scope of this study is to describe the first series of Renier's 'H' technique to be applied in children with SC outside of France.

METHODS

A consecutive review is made of the medical records of children hospitalized in the last 6 years (between March 2007 and March 2013) with isolated SC in whom Renier's 'H' technique was performed.

RESULTS

Thirteen children met the criteria for inclusion in the study. Considering medical evaluation and parental satisfaction, the evaluation of postsurgical cranial reconstruction was classified as satisfactory in all cases.

CONCLUSIONS

We consider the Renier's H technique to be effective in the cranial reshaping of children with isolated SC, with satisfactory esthetic postsurgical results.

Cranial compression using distractors in reverse fashion as an alternative method for correcting scaphocephaly in older patients

BACKGROUND

Intraoperative calvarial contraction of conventional calvarial remodeling is more difficult in scaphocephaly patients who are 1 year or older in age. In our current study, gradual cranial compression with a distractor was used to correct scaphocephaly in this older age group and the surgical results were quantitatively analyzed.

METHODS

Gradual cranial compression was used to treat 7 sagittal craniosynostosis patients. The mean age was 20.9 months (range, 12-32 months) and the mean follow-up period was 65 months (range, 3-81 months). Computed tomography was used to calculate the cephalic index (CI; equal to the maximum width of the head/maximum length of the head ×100), and the ratios of these indices at 3 different time periods (before, immediately after, and at 1 year postoperatively) were evaluated.

RESULTS

An average cranial compression of 18 mm was found to be possible with an average CI increase from 67.9 to 73.5. The CI ratio at 1 year after surgery was found to be the highest, showing a 9.8% increase.

CONCLUSION

Sagittal craniosynostosis patients are less easy to treat with conventional calvarial remodeling surgery if they are older than 1 year. Gradual cranial vault compression with distractors can be another option in these cases.

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.

Development of secondary unilateral coronal suture synostosis with a sagittal suture synostosis in a nonsyndromic patient

Multiple-suture synostosis is typically associated with syndromic craniosynostosis but has been occasionally reported in large series of nonsyndromic children. The diagnosis of multiple fused sutures usually occurs at the same time, but rarely has the chronological development of a secondary suture synostosis been noted. The development of secondary bicoronal suture synostosis requiring surgical intervention has only been reported, to date, after surgical intervention and is hypothesized to arise from a disruption of inhibitory factors from the dura. The disinhibition of these factors permits the sutures to then fuse at an early stage. The authors report on a patient who developed secondary unilateral coronal synostosis after the diagnosis of an isolated sagittal synostosis. The secondary synostosis was identified at the time of the initial surgical intervention and ultimately required a second procedure of a frontoorbital advancement. The clinical appearance of this phenomenon may be subtle, and surgeons should monitor for the presence of secondary synostosis during surgery as it may require intervention. Failure to identify the secondary synostosis may necessitate another surgery or result in a poor cosmetic outcome. The authors recommend close clinical follow-up for the short term in patients with isolated sagittal synostosis.