Mini-invasive surgical technique for sagittal craniosynostosis

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.

Improved cephalic index following early cranial vault remodeling in patients with isolated nonsyndromic sagittal synostosis

OBJECTIVE

Isolated nonsyndromic sagittal synostosis (SS) is the most common form of craniosynostosis in children, accounting for approximately 60% of all craniosynostoses. The typical cranial measurement used to define and follow SS is the cephalic index (CI). Several surgical techniques have been suggested, but agreement on type and timing of surgery is lacking. This study aimed to evaluate the authors' institutional experience of surgically treating SS using a modified subtotal cranial vault remodeling technique in a population-based cohort. Special attention was directed toward the effect of patient age at time of surgery on long-term CI outcome.

METHODS

A retrospective analysis was conducted on all patients with isolated nonsyndromic SS who were surgically treated from 2003 to 2011. Data from electronic medical records were gathered. Eighty-two patients with SS were identified, 77 fulfilled inclusion criteria, and 72 had sufficient follow-up data and were included. CI during follow-up after surgery was investigated with ANOVA and a linear mixed model.

RESULTS

In total, 72 patients were analyzed, consisting of 16 females (22%) and 56 males (78%). The mean ± SD age at surgery was 4.1 ± 3.1 months. Blood transfusions were received by 81% of patients (26% intraoperatively, 64% postoperatively, 9% both). The mean ± SD time in the pediatric ICU was 1.1 ± 0.25 days, and the mean ± SD total hospital length of stay was 4.6 ± 2.0 days. No patient required reoperation. The mean ± SD CI increased from 69 ± 3 to 87 ± 5 for patients who underwent surgery before 45 days of age. Surgery resulted in a larger increase in CI for patients who underwent surgery at a younger age compared with older patients (p < 0.05, Tukey's HSD test). In the comparison of patients who underwent surgery before 45 days of age with patients who underwent surgery at 45-90, 90-180, and more than 180 days of age, the linear mixed model estimated a long-term loss of CI of 3.0, 5.5, and 7.4 points, respectively.

CONCLUSIONS

The modified subtotal cranial vault remodeling technique used in this study significantly improved CI in patients with SS. The best results were achieved when surgery was performed early in life.

Minimally invasive endoscopically assisted remodelation (MEAR) of sagittal craniosynostosis: an alternative technique to open and endoscopic procedures with cranial orthosis time span reduction

INTRODUCTION

Sagittal craniosynostosis represents the most frequent simplex skull suture pathology. There are currently several operative approaches to this defect. Minimally invasive techniques are preferred for young infants. Since July 2017, we have employed endoscopically assisted craniectomies followed by cranial orthosis. Gradually, we have developed our modified technique, the minimally invasive endoscopically assisted remodelation (MEAR).

SURGICAL TECHNIQUE

MEAR is a combination of principles gained from classical cranial vault remodeling techniques and minimal invasive approaches. The long and wider lateral osteoectomies performed in the parietal and occipital bones along with loosening of the periosteum and dura adhesions at the lambdoid sutures lead to early correction of parieto-occipital dimensions.

RESULTS

Thirty-one consecutive patients with scaphocephaly underwent MEAR. The median preoperative cephalic index of 67 units (P25:63.3, P75:70) was improved to a median postoperative cephalic index of 77 units (P25:75, P75: 81). Sufficient correction was achieved in all patients. Cranial orthosis was needed for a median of 1.5 months (P25:1, P75:2). We had no major surgical complications in this pilot series.

CONCLUSIONS

With MEAR, we have achieved good cosmetic results. Duration of cranial orthosis was significantly shortened compared to conventional endoscopic-assisted procedures.

The scalp block for postoperative pain control in craniosynostosis surgery: a case control study

PURPOSE

Postoperative analgesia after corrective surgery of pediatric craniosynostosis is crucial in terms of short- and long-term outcomes. The objective of this observational study was to evaluate the effectiveness of an analgesic technique based on the scalp block versus traditional pharmacological approach.

METHODS

Thirteen patients, aged between 3 months and 2 years, undergoing surgical correction of craniosynostosis, received scalp nerve block before awakening (scalp block group). This group of patients was compared to a second group of 13 patients, retrieved from our database, treated with the traditional pharmacological approach (control group). Pain scores, need of rescue therapy, resumption of oral nutrition, degree of parent satisfaction at discharge, and length of stay in the Pediatric Intensive Care Unit (PICU) and in the hospital were compared between the two groups.

RESULTS

Objective Pain Score values were significantly lower in patients treated with scalp block at 30 min and at 8 h after extubation. The number of pharmacological interventions for the treatment of pain in PICU was significantly higher in Control group. Children in Scalp block group started earlier oral feeding than in Control group, both for clear fluids and milk. Length of stay in PICU was longer in Scalp block group than in Control group, though the difference between the mean data in the two groups is about 3 . This difference does not seem significant from a clinical standpoint, since it seems more related to logistic issues (e.g., availability of bed in the Pediatric Neurosurgery Unit, presence of a parent), rather than clinical problems contraindicating the discharge from PICU. Indeed, the overall hospital length of stay was similar between the two groups.

CONCLUSION

Scalp nerve block was effective for immediate postoperative pain control in patients younger than 2 years who underwent cranioplasty for craniosynostosis. The best pain control compared to conventional therapy allowed to limit the need for rescue analgesics in PICU and an earlier recovery time. ClinicalTrials.gov Identification: NCT04133467.

Effect of Operative Timing and Bone Grafting on Postoperative Cephalometric Indices in Nonsyndromic Sagittal Synostosis

ABSTRACT

Surgical repair of sagittal suture craniosynostosis is highly variable, and optimal timing/use of bone grafts remains a subset of parameters that continue to be studied. We sought to compare cephalometric outcomes of early surgical intervention without bone grafting compared to later intervention with bone grafting. Patients undergoing primary surgical repair of nonsyndromic sagittal suture craniosynostosis between 2015 and 2019 were followed with preoperative measurements of cephalic index along with postoperative measurements at 6 months to 1 year, respectively. Nineteen patients undergoing cranial vault reconstruction were studied in 2 groups, namely those younger than 6 months who did not have bone grafting performed during primary repair (31.6%) and patients 6 months and older who underwent cranial vault reconstruction with bone grafting during primary repair (68.4%). Mean 6-month to 1-year postoperative cranial index was significantly increased in both groups (P < 0.001). The average cephalic index change for both groups (younger than 6 months without bone grafting, CI value change 9; 6 months and older with bone grafting; CI value change 6) was not significantly different with regards to 95% confidence interval (P = 0.30). Patients older than 6 months of age undergoing cranial vault reconstruction with bone grafting have similar cephalometric outcomes as their younger counterparts undergoing cranial vault remodeling without bone grafting. Bone grafting in the appropriate cohort may improve functional and esthetic outcomes without compromising primary surgical goals of improving cranial vault cephalometric indices.

GLI1 and AXIN2 Are Distinctive Markers of Human Calvarial Mesenchymal Stromal Cells in Nonsyndromic Craniosynostosis

All skeletal bones house osteogenic stem cell niches, in which mesenchymal stromal cells (MSC) provide progenitors for tissue growth and regeneration. They have been widely studied in long bones formed through endochondral ossification. Limited information is available on the composition of the osteogenic niche in flat bones (i.e., skull vault bones) that develop through direct membranous ossification. Craniosynostosis (CS) is a congenital craniofacial defect due to the excessive and premature ossification of skull vault sutures. This study aimed at analysing the expression of GLI1, AXIN2 and THY1 in the context of the human skull vault, using nonsyndromic forms of CS (NCS) as a model to test their functional implication in the aberrant osteogenic process. The expression of selected markers was studied in NCS patients' calvarial bone specimens, to assess the in vivo location of cells, and in MSC isolated thereof. The marker expression profile was analysed during in vitro osteogenic differentiation to validate the functional implication. Our results show that GLI1 and AXIN2 are expressed in periosteal and endosteal locations within the osteogenic niche of human calvarial bones. Their expression is higher in MSC isolated from calvarial bones than in those isolated from long bones and tends to decrease upon osteogenic commitment and differentiation. In particular, AXIN2 expression was lower in cells isolated from prematurely fused sutures than in those derived from patent sutures of NCS patients. This suggests that AXIN2 could reasonably represent a marker for the stem cell population that undergoes depletion during the premature ossification process occurring in CS.

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.

Partial hybrid cranial vault remodeling in late correction of scaphocephaly and revision surgery. A monocentric retrospective study of nine consecutive cases

There is currently no consensus on the surgical attitude to be adopted for late management of sagittal synostosis or for revision scaphocephaly surgeries without prolapse of the cerebellar tonsils. We present here a monocentric retrospective study of nine patients operated consecutively by a fixed expansion method of the cranial vault which may be associated with a fronto-orbital remodeling. The procedure consists in the realization of multiple parietal tongue-in-groove osteotomies fixed by resorbable plates. Simultaneous fronto-orbital remodeling have been performed when needed. No intraoperative complication was noted. The average operating time was 141min. Six patients (66.7%) had a blood transfusion during the perioperative period. The average hospital stay was 4.8days. With a mean follow-up of 26,7months, no surgical revision was noted. In all patients with clinical or ophthalmologic signs of intracranial hypertension, we highlighted a disappearance of signs within 4months. No protective helmet has been used. The craniofacial remodeling was judged very good by the family and the surgical team. Multiple tongue-in-groove tenons remolding cranioplasty associated or not with a fronto-orbital advancement is a safe technique. It seems to us to be a good alternative to floating or fixed bi-parietal or bi-parieto-frontal cranial flaps because of the very large increase in endocranial volume and the possibility of physiologically and aesthetically remodeling the parietal and fronto-orbital regions.

A New Technique for Sagittal Synostosis: A Plurality of Small Incisions Minimally Invasive Technique Used on Infants and Young Patients

OBJECTIV

The authors devised a multiple small incisions minimally invasive technique for use in isolated nonsyndromic sagittal synostosis to achieve better esthetic effect and satisfactory reshaping of the calvarial vault. The purpose of this study is to provide clinicians with new and feasible solution.

METHODS

From April 2016 to January 2017, 5 male patients were successfully treated with minimally invasive surgery. The age ranges from 1.5 to 3.3 years. The authors designed 9 short skin linear incisions (2-3 cm long) strategically to disperse in the scalp. The patient was assessed in a series including sex, age of surgery, blood loss, blood transfusion, duration of surgery, postoperative complications, preoperative and postoperative cephalic index (CI), length of stay (LOS), esthetic outcomes, and intellectual developmental quotient (DQ).

RESULTS

The shortest operation time is 1.5 hours. The shortest hospital stay is 6 days. The blood loss ranged from 135 to 280 mL. No serious complications occurred during the follow-up time. Postoperative 3-dimensional CT scan showed that the extensive floating bone formed well. Preoperative CI ranged from 64.2 to 68 and postoperatively 69.4 to 74.3. Mental development was tested by children heath care practioners, significantly improving DQ from 67 to 81 preoperatively and 76 to 90 postoperatively. All children receive good esthetic results.

CONCLUSION

The new technique is safe and effective. The advantages are satisfactory: calvarial fornix remodeling, less visible appearance of scars, shorter length of surgery, lower mental and financial stress, optimal age for surgery, no endoscopic adjuvant and postoperative helmet are needed.

Expansion and compression distraction osteogenesis based on volumetric and neurodevelopmental analysis in sagittal craniosynostosis

PURPOSE

Distraction osteogenesis (DO) is a less daunting procedure than extensive cranial vault remodeling and has been used to correct sagittal craniosynostosis. The purposes of this study are to describe DO in combination with expansion and compression procedures and to report analytic results based on the cranial index (CI), volumetric measurement, and neurodevelopmental tests.

METHODS

Between June 2002 and May 2013, 32 patients with non-syndromic sagittal synostosis who had undergone antero-posterior compression with bitemporal expansion were recruited. Circumferential baseline, mid-sagittal, and bicoronal craniotomies were performed in addition to four-quadrant bone flap procedures via distraction with dural attachment. CI, intracranial volume (ICV), head circumference (HC), and neurodevelopmental outcomes using the Bayley Scales of Infant Development-II (BSID-II) scoring system were analyzed.

RESULTS

Dolichocephalic CI (68.85 ± 3.61) was altered to mesocephalic CI (78.28 ± 3.74) postoperatively. Preoperative ICV and HC determinations were within the normal range for the majority of participants (normal ICV 87.5%, n = 28; normal HC 75%, n = 24). ICV and HC did not show significant changes with postoperative measurements and were maintained within normal ranges. Regarding neurodevelopment, both the mental and psychomotor developmental indices (MDI, PDI) demonstrated significant improvement (MDI, 88.69 ± 17.38 to 96.23 ± 21.05; PDI, 91.38 ± 16.31 to 100 ± 11.51; p < 0.05).

CONCLUSIONS

Symmetric sagittal synostosis can be treated comprehensively through DO in combination with expansion and compression procedures. ICV and HC measurements were useful for designing surgical and postoperative distraction strategies. Achievement of mesocephalic CI and neurodevelopmental improvement validated morphological and functional effectiveness.

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%).

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.