Spring mediated dynamic craniofacial reshaping. Case report

Continuous Intracranial Pressure Monitoring in 24 Microcephalic Children with Developmental Delay: A Significant Portion of Microcephalic Children with Developmental Delay Have High Intracranial Pressure

OBJECTIVE

The new direct gradual cranial expansion surgical technique has been used to treat children with postshunt microcephaly and slit ventricle syndrome. To evaluate the feasibility of this new surgical treatment, we studied intracranial pressure (ICP) in microcephalic children with developmental delay.

METHODS

Mean ICP, age, sex, head size, and developmental assessments were compared in 24 microcephalic children with developmental delay who had had continuous ICP monitoring.

RESULTS

Children studied included 9 boys and 15 girls with a mean age of 4.9 ± 2.0 years. Mean ICP was 18.7 ± 8.6 mm Hg. Children with high ICP had significantly lower age and higher B wave ratios than children with low ICP. There were no statistically significant differences in developmental scores and head sizes between children with high ICP and children with low ICP. In multiple linear regression analysis, we observed significantly increased risk of mean ICP elevation by B wave ratio and developmental score and decreased risk of mean ICP elevation by age, but not significantly increased risk of mean ICP elevation by head circumferences (z score).

CONCLUSIONS

Our findings suggest that a portion of microcephalic children with developmental delay have high ICP that cannot be expected from head sizes, and high ICP has decreasing tendency with age.

Endoscopy-assisted craniosynostosis surgery followed by helmet therapy

Background

Surgical methods to treat craniosynostosis have evolved from a simple strip craniectomy to a diverse spectrum of partial or complete cranial vault remodeling with excellent results but often with high comorbidity. Therefore, minimal invasive craniosynostosis surgery has been explored in the last few decades. The main goal of minimal invasive craniosynostosis surgery is to reduce the morbidity and invasiveness of classical surgical procedures, with equal long-term results, both functional as well as cosmetic.

Methods

To reach these goals, we adopted endoscopy-assisted craniosynostosis surgery (EACS) supplemented with helmet molding therapy in 2005.

Results

We present in detail our surgical technique used for scaphocephaly, trigonocephaly, plagiocephaly, complex multisutural, and syndromic cases of craniosynostosis.

Conclusions

We conclude that EACS with helmet therapy is a safe and suitable treatment option for any type of craniosynostosis, if performed at an early age, preferably around 3 months of age.

Spring-Assisted Surgery in the Treatment of Complex Craniosynostosis

Multisutural nonsyndromic craniosynostosis is a rare group of malformations, whose frequency has been reported between 3% and 7% of all craniosynostosis. The clinical diagnosis can be difficult and computed tomography is usually required. Surgical treatment is challenging and staged procedures are performed in up to 80% of patients. The aim of the present study was to determine the reoperation rate and to evaluate the surgical outcomes by measuring intracranial volume (ICV) preoperatively and at follow-up, and comparing it to a control group. Perioperative variables and reoperation rate were recorded. Fifty-one patients presented with a complex pattern of synostosis without a recognizable syndrome (5% of cases of total patients evaluated). Fifteen patients have been treated with spring-assisted surgery, either alone or in combination with a foreheadplasty. The mean follow-up was 6.2 years. The mean preoperative ICV of the patients was smaller, but not significantly, than in the normal population (P = 0.13). Postoperatively, the mean ICV was similar to that of the control group at 1 year (P = 0.92), while at 3 years it was appreciably smaller, although not significantly different (P = 0.06). Five patients (33%) went through a secondary skull expansion for either raised intracranial pressure or cosmetic reasons. Spring-assisted surgery seems to temporarily expand ICV in children with complex synostosis and lower the reoperation rate, thus reducing the need for a second procedure. A longer follow-up would be necessary to further investigate the effects of springs over time.

Assessment of spring cranioplasty biomechanics in sagittal craniosynostosis patients

OBJECTIVE Scaphocephaly secondary to sagittal craniosynostosis has been treated in recent years with spring-assisted cranioplasty, an innovative approach that leverages the use of metallic spring distractors to reshape the patient skull. In this study, a population of patients who had undergone spring cranioplasty for the correction of scaphocephaly at the Great Ormond Street Hospital for Children was retrospectively analyzed to systematically assess spring biomechanical performance and kinematics in relation to spring model, patient age, and outcomes over time. METHODS Data from 60 patients (49 males, mean age at surgery 5.2 ± 0.9 months) who had received 2 springs for the treatment of isolated sagittal craniosynostosis were analyzed. The opening distance of the springs at the time of insertion and removal was retrieved from the surgical notes and, during the implantation period, from planar radiographs obtained at 1 day postoperatively and at the 3-week follow-up. The force exerted by the spring to the patient skull at each time point was derived after mechanical testing of each spring model-3 devices with the same geometry but different wire thicknesses. Changes in the cephalic index between preoperatively and the 3-week follow-up were recorded. RESULTS Stiffer springs were implanted in older patients (p < 0.05) to achieve the same opening on-table as in younger patients, but this entailed significantly different-higher-forces exerted on the skull when combinations of stiffer springs were used (p < 0.001). After initial force differences between spring models, however, the devices all plateaued. Indeed, regardless of patient age or spring model, after 10 days from insertion, all the devices were open. CONCLUSIONS Results in this study provide biomechanical insights into spring-assisted cranioplasty and could help to improve spring design and follow-up strategy in the future.

Integration of Brain and Skull in Prenatal Mouse Models of Apert and Crouzon Syndromes

The brain and skull represent a complex arrangement of integrated anatomical structures composed of various cell and tissue types that maintain structural and functional association throughout development. Morphological integration, a concept developed in vertebrate morphology and evolutionary biology, describes the coordinated variation of functionally and developmentally related traits of organisms. Syndromic craniosynostosis is characterized by distinctive changes in skull morphology and perceptible, though less well studied, changes in brain structure and morphology. Using mouse models for craniosynostosis conditions, our group has precisely defined how unique craniosynostosis causing mutations in fibroblast growth factor receptors affect brain and skull morphology and dysgenesis involving coordinated tissue-specific effects of these mutations. Here we examine integration of brain and skull in two mouse models for craniosynostosis: one carrying the FGFR2c C342Y mutation associated with Pfeiffer and Crouzon syndromes and a mouse model carrying the FGFR2 S252W mutation, one of two mutations responsible for two-thirds of Apert syndrome cases. Using linear distances estimated from three-dimensional coordinates of landmarks acquired from dual modality imaging of skull (high resolution micro-computed tomography and magnetic resonance microscopy) of mice at embryonic day 17.5, we confirm variation in brain and skull morphology in Fgfr2c^C342Y/+ mice, Fgfr2^+/S252W mice, and their unaffected littermates. Mutation-specific variation in neural and cranial tissue notwithstanding, patterns of integration of brain and skull differed only subtly between mice carrying either the FGFR2c C342Y or the FGFR2 S252W mutation and their unaffected littermates. However, statistically significant and substantial differences in morphological integration of brain and skull were revealed between the two mutant mouse models, each maintained on a different strain. Relative to the effects of disease-associated mutations, our results reveal a stronger influence of the background genome on patterns of brain-skull integration and suggest robust genetic, developmental, and evolutionary relationships between neural and skeletal tissues of the head.

Review of Past Reports and Current Concepts of Surgical Management for Craniosynostosis

The purposes of surgery for craniosynostosis are to release increased intracranial pressure and to normalize cranial shape. The procedure was developed from a simple strip craniectomy in practice which ranged from the removal of the fused suture before the 1960s to total calvarial remodeling after 1970s and later methods of the 1990s, such as distraction and its modifications. According to its history, craniofacial surgeons might be changing their procedures with more effective, than less invasive ways. Since the late 1990s, when the distraction was applied to the craniofacial surgery, the gradual expansion, in particular of the anterior cranium, common in Japan, has long been controversial until the Caucasians accepted its use for the posterior cranium. Currently, the method may revert to the old procedure because a more sophisticated and better morphological result can be obtained depending on the types of deformity, even if a little more invasive maneuver is required. In other words, if treatment can be performed in optimal time, the procedures that were developed in the last half a century should be altered to each condition.

A Systematic Approach to Predicting Spring Force for Sagittal Craniosynostosis Surgery

Spring-assisted surgery (SAS) can effectively treat scaphocephaly by reshaping crania with the appropriate spring force. However, it is difficult to accurately estimate spring force without considering biomechanical properties of tissues. This study presents and validates a reliable system to accurately predict the spring force for sagittal craniosynostosis surgery. The authors randomly chose 23 patients who underwent SAS and had been followed for at least 2 years. An elastic model was designed to characterize the biomechanical behavior of calvarial bone tissue for each individual. After simulating the contact force on accurate position of the skull strip with the springs, the finite element method was applied to calculating the stress of each tissue node based on the elastic model. A support vector regression approach was then used to model the relationships between biomechanical properties generated from spring force, bone thickness, and the change of cephalic index after surgery. Therefore, for a new patient, the optimal spring force can be predicted based on the learned model with virtual spring simulation and dynamic programming approach prior to SAS. Leave-one-out cross-validation was implemented to assess the accuracy of our prediction. As a result, the mean prediction accuracy of this model was 93.35%, demonstrating the great potential of this model as a useful adjunct for preoperative planning tool.

Craniofacial Surgery over 30 Years in Göteborg

Craniofacial surgery is a new sub-specialty in the field of plastic reconstructive surgery and is dedicated to the treatment of severe cranial and facial malformations. Craniofacial surgery gradually started in Göteborg in the late 1970's and has been acting as the Scandinavian center since 1983.

Over these 30 years an almost complete change in surgical techniques has evolved. Also profound changes in timing of surgery have followed. Results have been dramatically improved based on critical evaluation of standardized registration of long-term results.

One of the most dramatic developments has been the introduction of implantable stainless steel springs. This has changed the treatment of Craniosynostosis completely and has made midfacial advancement procedures possible without relapse.

[Rational use of distraction osteogenesis in craniofacial surgery]

Distraction osteogenesis, initially developed by Ilizarov for limb, is the tissular extension caused by the progressive space of the osseous pieces following an osteotomy. Distraction is osteogenesic and histogenic. Twenty-five years ago, at the instigation of McCarthy, this technique was used to handle the craniofacial malformations in the various floors of the face : mandibular, mediofacial and cranial. The most wide-spread protocols respect a latency period from 0 to 7 days, a rhythm of distraction from 1 to 2mm a day in 2 at 4 times and a period of consolidation from 4 to 8 weeks. Distraction is the result of the inventiveness of the pioneers then the work to always adapt to the multiple complex clinical situations. The surgeon has to choose between internal or external materials allowing a mono- or multi-vectorial extension, in osseous and/or dental anchoring. The mandibular distraction is very effective for the treatment of the secondary obstructive syndromes in the unilateral or bilateral severe hypomandibular malformations. She also allows desobstruction of the superior airways within the framework of the mediofacial hypoplasies as well as the secondary treatment of the growth defects in cleft lips and palates. Finally, the distraction osteogenesis enhanced reliability of the fronto-facial advancement in early and secondary treatment of craniofaciosynostosis. This is a real support of the facial growth, which has to be included in a plan of global treatment.

Safety of Open Cranial Vault Surgery for Single-Suture Craniosynostosis: A Case for the Multidisciplinary Team

INTRODUCTION

Single Suture Craniosynostosis (SSC) occurs in 1 in 2,500 live births and is the most common type of craniosynostosis treated in most centers. Surgical treatment has evolved over the past century and open techniques are tailored to the specific suture type. Additionally, the concept of multi-disciplinary team care has proliferated and is becoming the standard of care for SSC. The combination of these evolutions, we believe, has improved the safety of cranial vault surgery for SSC.

METHODS

A retrospective review of patients participating in the Infant Learning Project at Seattle Children's Hospital who underwent cranial vault surgery for treatment of SSC between 2002 and 2006 was performed. Pre-operative assessment, surgical techniques, anesthetic and intraoperative events and both intra-operative and post-operative adverse events were analyzed.

RESULTS

Eighty eight patients fulfilled the inclusion criteria (42 sagittal, 23 metopic, 19 unicoronal, 4 lambdoid). Length of procedure varied (FOA 5.2 hrs, modified pi 2.5 hrs, total vault 4.9 hrs and switch cranioplasty 4.6 hrs), as did transfusion amount (FOA 385 mL, modified pi 216 mL, total vault 600 mL, switch cranioplasty 207 mL) although 99% of patients received a transfusion of some sort. There were no deaths and no major intraoperative complications. Minor events include; ET tube malposition (1), desaturation (1), acidosis (1), hypothermia (9), coagulopathy (2), Hct < 25 (55). Average hospital stay was 3.4 days with no major post-operative complications. One patient was readmitted to the ICU and 1 had a scalp hematoma, but no patients returned to the operating room within 6 months after surgery.

DISCUSSION

The surgical treatment of SSC has evolved from lengthy, risky procedures to become almost routine at most craniofacial centers. Additionally, the care for patients with SSC has evolved from a single provider to a multidisciplinary team concept based around protocols for workup, delivery of anesthesia, streamlined surgical procedures and post-operative care and assessment. This evolution has given open cranial vault surgery for SSC an acceptable safety profile.

Photometric evaluation of cranial and facial symmetry in hemicoronal single suture synostosis treated with surgical fronto-orbital remodeling

OBJECTIVE

Evaluation of frontal vault symmetry and progressive facial symmetrization in a cohort of patients with hemicoronal single suture synostosis treated with a standardized cranioplasty and rigid fixation.

PATIENTS AND METHODS

Fifty-four patients with hemicoronal synostosis operated between 1999 and 2014 were reviewed retrospectively. Pre, immediately postoperative and yearly photographs from the top of the skull and frontal views of the face were taken with the same head position and projection. A photogrammetric method was applied to quantify the pre and postoperative contour changes. The anterior skull hemispheres were traced, divided into two equal parts and the areas were compared. Angular measurements obtained by the intersection of the interpupillary line and the glabella perpendicular vertical line were calculated. The average photographic follow-up was 6.8 years. Range 1-14 years.

RESULTS

The average advancement on the affected side was 18 mm (range: 16-23 mm). The pre-surgical cranial area on the affected side was increased on average 14.6 + 2.4% (range: 10-18%). The angular measurements documented the frontal symmetry obtained and the progressive improvement of facial symmetry.

CONCLUSION

Cranioplasty with rigid fixation achieved a stable correction of anterior plagiocephaly leading to subsequent symmetrical facial growth. Photogrammetry allowed fora quantitative long-term validation.

Operative Management of Nonsyndromic Sagittal Synostosis: A Head-to-Head Meta-analysis of Outcomes Comparing 3 Techniques

BACKGROUND

The timing and surgical technique for the treatment of sagittal synostosis remain controversial. Calvarial vault remodeling (CVR), strip craniectomy (SC), and spring-mediated cranioplasty (SMC) are currently in use. We perform a meta-analysis of the literature to compare these 3 techniques.

METHODS

A literature search identified articles involving operative management of nonsyndromic sagittal synostosis. Comparison of 2 operative techniques was required, and methodology was assessed via the American Society of Plastic Surgeons' Levels of Evidence. Three techniques were considered: CVR, SC, and SMC. Meta-analysis was conducted for change in cephalic index (CI), reported as weighted mean difference (WMD). Pooled subgroup comparisons were performed for operative time, length of stay, blood loss, and cost.

RESULTS

Twelve studies providing level 2 or 3 evidence were included. All studies involved CVR (n = 187), 8 involved SC (n = 299), and 7 involved SMC (n = 158). Head-to-head comparison of change in CI demonstrated a greater, yet statistically insignificant change for CVR versus SMC, WMD = 0.94 (-0.23 to 2.11) (P = 0.12, I(2) = 55%). Calvarial vault remodeling showed a statistically greater change in CI versus SC, WMD = 1.47 (0.47-2.48) (P = 0.004, I(2) = 66%). Compared with SMC/SC, CVR had longer operative length (170 vs 97 minutes), higher blood loss (238 vs 47 mL), longer length of stay (5.1 vs 2.9 days), and higher costs ($35,280 vs $13,147), all with P < 0.0001.

CONCLUSIONS

This study, the first meta-analysis comparing 3 primary operations for correcting nonsyndromic sagittal synostosis, demonstrates no difference in CI for CVR versus SMC and a small but statistically greater improvement in CI favoring CVR over SC. Secondary outcomes favored SC/SMC procedures over CVR. However, long-term studies are still needed to adequately assess the risk-benefit ratios.

Transsutural distraction osteogenesis for 285 children with craniosynostosis: a single-institution experience

OBJECT Although distraction osteogenesis (DO) requires a secondary procedure in the surgical correction of craniosynostosis, it is relatively simple, requires less transfusion, results in a shorter intensive care unit stay, and is quite safe. Because of these positive factors, various DO techniques have been developed. However, there is disagreement regarding the superiority of DO. The authors reported on a new DO technique, transsutural DO (TSDO), 6 years ago that was performed in 23 patients over a period of 6 months, and it continues to be used at the present time. In this paper the authors report the results of TSDO performed in 285 patients with craniosynostosis over a period of 6 years at a single institution. METHODS TSDO consists of a simple suturectomy of the pathological suture followed by direct distraction of the suturectomy site only. Types of TSDO conducted included sagittal TSDO in 95 patients, bicoronal in 14, unilateral coronal in 57, lambdoid in 26, metopic in 13, multiple in 19, syndromic in 33, and secondary in 28. The mean age (± SD) of the patients was 19.4 ± 23.0 months, and mean follow-up was 39.5 ± 21.0 months. RESULTS The mean operating time was 115 ± 43 minutes, and mean anesthesia time was 218 ± 56 minutes. The mean transfusion volume of red blood cell components was 48 ± 58 ml, and mean transfusion volume of fresh-frozen plasma was 19 ± 35 ml. Total transfusion volume was significantly less in infants younger than 12 months of age and in children with lower lumbar puncture pressures (p < 0.05). Complications included 1 (0.4%) death from postoperative acute pneumonia after a distractor removal operation and 23 (8%) surgical morbidities comprising 10 revisions (3.5%) and 13 early removals of distracters (4.6%). CONCLUSIONS TSDO is a simple, effective, and safe method to use for treating all types of craniosynostosis. Some morbidity was experienced in this study, but it may be attributed to the learning curve of the technique.

Piezosurgical Suturectomy and Sutural Distraction Osteogenesis for the Treatment of Unilateral Coronal Synostosis

Different surgical procedures are used for the treatment of synostosis. Among them, suturectomy and sutural distraction osteogenesis (SDO) are suitable for young infant patients. In this report, we present the case of a young infant patient with a clear synostosis of the left coronal suture, which was treated by piezoelectric suturectomy combined with SDO and 2 internal distractors. One-year follow-up showed good results. Thirty-six months after surgery, normal skull growth and shape were observed by 3D computed tomographic examination. No infection, bleeding, fistula, and other complications were observed. The results suggested that the treatment of unilateral coronal synostosis in young infant patient by piezosurgical suturectomy and SDO is to be preferred because of its simplicity and relatively minimal invasiveness.

Objective classification system for sagittal craniosynostosis based on suture segmentation

PURPOSE

Spring-assisted surgery is an effective and minimally invasive treatment for sagittal craniosynostosis (CSO). The principal barrier to the advancement of spring-assisted surgery is the patient-specific spring selection. The selection of spring force depends on the suture involved, subtypes of sagittal CSO, and age of the infant, among other factors. Clinically, physicians manually judge the subtype of sagittal CSO patients based on their CT image data, which may cause bias from different clinicians. An objective system would be helpful to stratify the sagittal CSO patients and make spring choice less subjective.

METHODS

The authors developed a novel informatics system to automatically segment and characterize sutures and classify sagittal CSO. The proposed system is composed of three phases: preprocessing, sutures segmentation, and classification. First, the three-dimensional (3D) skull was extracted from the CT images and aligned with the symmetry of the cranial vault. Second, a "hemispherical projection" algorithm was developed to transform 3D surface of the skull to a polar two-dimensional plane. Through the transformation, an "effective" projected region can be obtained to enable easy segmentation of sutures. Then, the different types of sutures, such as coronal sutures, lambdoid sutures, sagittal suture, and metopic suture, obtained from the segmented sutures were further identified by a dual-projection technique of the midline of the sutures. Finally, 108 quantified features of sutures were extracted and selected by a proposed multiclass feature scoring system. The sagittal CSO patients were classified into four subtypes: anterior, central, posterior, and complex with the support vector machine approach. Fivefold cross validation (CV) was employed to evaluate the capability of selected features in discriminating the four subtypes in 33 sagittal CSO patients. Receiver operating characteristics (ROC) curves were used to assess the robustness of the developed system.

RESULTS

The segmentation results of the proposed method were clinically acceptable for the qualitative evaluation. For the quantitative evaluation, the fivefold CV accuracy of the classification for the four subtypes was 72.7%. This classification system was reliable with the area under curve (in ROC analysis) being greater than 0.8 for four two-class problems.

CONCLUSIONS

The proposed hemispherical projection algorithm based on backtracking search can successfully segment sutures of the cranial vault. The classification system can also offer a desirable performance. As a result, the proposed segmentation and classification system is expected to bring insights into clinic research and the selection of the spring force to facilitate widespread application of this minimally invasive treatment.

Spring-assisted cranial vault expansion in the setting of multisutural craniosynostosis and anomalous venous drainage: case report

Patients with multisutural craniosynostosis can develop anomalous venous connections between the intracranial sinuses and cutaneous venous system through enlarged emissary veins. Cranial vault remodeling in this subset of patients carries the risk of massive intraoperative blood loss and/or occlusion of collateral draining veins leading to intracranial venous hypertension and raised intracranial pressure, increasing the morbidity of cranial expansion. The authors report the use of spring-mediated expansion as a technique for cranial reconstruction in which the collateral intracranial venous drainage system can be preserved. A patient with bilateral lambdoid, sagittal, and unicoronal synostosis presented for cranial reconstruction. A tracheostomy and ventriculoperitoneal shunt were placed prior to intervention. At the time of reconstruction, a Luckenschadel skull abnormality and Chiari malformation Type I were present. A preoperative CT venogram demonstrated large collateral superficial occipital veins, small bilateral internal jugular veins, and hypoplastic jugular foramina. Collateral flow from the transverse and sigmoid sinuses through large occipital emissary veins was seen. Spring-mediated cranial vault expansion was performed with care to preserve the large collateral veins at the occipital midline. Four springs were placed at each lambdoid and the posterior and anterior sagittal sutures following 1-cm strip suturectomies. Removal of the springs was performed 2 months postoperatively. Cranial vault expansion was performed without disturbing the aberrant intracranial/extracranial venous collateral system. Estimated blood loss was 150 ml. A CT scan obtained 3 months postoperatively showed resolution of the Luckenschadel deformity and a 40% volumetric increase in the skull compared with the preoperative CT. Patients with anomalous venous drainage patterns and multisutural synostosis can undergo spring-mediated cranial vault expansion while preserving the major emissary veins draining the intracranial sinuses. Risks of blood loss, intracranial venous hypertension, and increased intracranial pressure may be decreased compared with traditional techniques of repair.

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%).

Spring-mediated sagittal craniosynostosis treatment at the Children’s Hospital of Philadelphia: technical notes and literature review

OBJECT

Sagittal craniosynostosis has been treated using both cranial remodeling techniques and modification of the sagittal strip craniectomy. A more recent technique is to implant springs in conjunction with a suturectomy to transversely expand the parietal bones to accommodate the growing brain. In this paper the authors describe and evaluate several modifications to the spring-mediated cranioplasty (SMC) technique, most notably use of an ultrasonic scalpel to limit dural dissection and maximize opening of the stenosed suture by placement of multiple spring devices. In addition, the literature is reviewed comparing SMC to other surgical treatments of sagittal synostosis.

METHODS

The authors retrospectively reviewed patients who presented to the Children’s Hospital of Philadelphia with a diagnosis of sagittal synostosis from August 2011 to November 2014. A pooled data set was created to compare our institutional data to previously published work. A comprehensive literature review was performed of all previous studies describing the SMC technique, as well as other techniques for sagittal synostosis correction.

RESULTS

Twenty-two patients underwent SMC at our institution during the study period. Patients were 4.2 months of age on average, had a mean blood loss of 56.3 ml, and average intensive care unit and total hospital stays of 29.5 hours and 2.2 days, respectively. The cranial index was corrected to an average of 73.7 (SD 5.2) for patients who received long-term radiological follow-up. When comparing the authors’ institutional data to pooled SMC data, blood loss and length of stay were both significantly less (p = 0.005 and p < 0.001, respectively), but the preoperative cranial index was significantly larger (p = 0.01). A review of the SMC technique compared with other techniques to actively expand the skull of patients with sagittal synostosis demonstrated that SMC can be performed at a significantly earlier age compared with cranial vault reconstruction (CVR).

CONCLUSIONS

The authors found that their institutional modifications of the SMC technique were safe and effective in correcting the cranial index. In addition, this technique can be performed at a younger age than CVRs. SMC, therefore, has the potential to maximize the cognitive benefits of early intervention, with lower morbidity than the traditional CVR.

The Total Calvarial Remodeling with Transsutural Distraction Osteogenesis of 21 Cases of Craniosynostosis: New, Efficient, Safe and Natural Method in Craniosynostosis Surgery

INTRODUCTION

The majority of the present distraction osteogenesis techniques involve local site expansion that only produces localized decompression and affords limited decompression and cosmetic results. We designed a new surgical procedure, total calvarial transsutural distraction osteogenesis (TSuDO).

METHODS

We performed total calvarial TSuDO surgical procedures in 21 children. The total calvarial TSuDO method consisted of suturectomy and distraction for the sagittal, bicoronal and bilambdoid sutures.

RESULTS

The mean surgery duration was 110 ± 16 min, the mean transfusion volume was 38 ± 45 ml, an average 4.1 ± 0.4 distractors were applied with a mean latency period of 3.3 ± 0.9 days. The mean activation period was 45 ± 18 days with a consolidation period of 54 ± 23 days. There were 3 complication cases of early removal of the distractors: 1 boy with transient 6th cranial nerve palsy accompanied by fever and 2 children with mild pus discharge from the distractor sites. Preoperative lumbar puncture pressures decreased significantly after distractor removal secondary to surgery (p < 0.001). The preoperative cranium size increased significantly (p < 0.001).

CONCLUSION

Total calvarial TSuDO is a simple and safe procedure that may produce wide generalized decompression and good cranial configurations that most closely resemble normal skulls.

Anesthesia for craniofacial surgery in infancy

Anesthetic management of infants undergoing craniofacial surgery can be challenging. Primary concerns for the anesthesiologist include blood loss and its management. The evolution of procedures to treat craniosynostosis has resulted in improvements in perioperative morbidity, including decreased blood loss and transfusion, shorter operations, and shorter hospital stays. An understanding of the procedures performed to treat craniosynostosis is necessary to provide optimal anesthetic management. Descriptions of current surgical techniques and approaches to anesthetic care are presented in this review.

Craniosynostosis

Craniosynostosis is a premature pathologic fusion of one or more cranial vault sutures that leads to abnormal shape of the skull. The fused sutures lead to restricted growth in some areas and compensatory bossing in other areas. The head may assume different shapes depending upon the site and timing of the abnormally fused suture. The exact cause of this suture pathology is still unknown, but the local dura, cranial base and the fibroblast growth factors seem to influence this. The diagnosis rests on clinical examination and confirmation is generally on the computed tomography scan. The need for surgery is both for cosmetic and functional reasons. Many cases may be associated with raised intracranial pressure with its attendant deleterious effects on vision and brain. The aim of treatment is to increase the cranial volume and reshape the skull. The surgery can be safely undertaken around 9-12 months in most of the cases. The conventional management is through an open surgical approach; although, some centres have claimed impressive results with limited endoscopic techniques in selected cases. The review article deals with the aetiopathogenesis, clinical presentations and management of the common varieties of craniosynostoses seen in the Indian scenario.

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.

Spring-assisted posterior vault expansion in multisuture craniosynostosis

PURPOSE

Patients with Apert and Crouzon syndromes and craniofrontonasal dysplasia need a vault expansion within the first year of life to treat or prevent the development of raised intracranial pressure. Many craniofacial units perform a conventional posterior vault expansion as initial surgery; an alternative to this technique is the spring-assisted posterior vault expansion. The purpose of this study was to demonstrate the efficacy of spring-assisted posterior vault expansion and to compare this technique with the conventional method.

METHODS

A retrospective study was conducted among all consecutive patients who received a posterior vault expansion between 2006 and 2011. Patients treated with springs were compared with patients treated with the conventional technique for blood loss, duration of surgery, postoperative hospital admittance, increase in skull circumference and anterior-posterior length, and complications.

RESULTS

Of the 31 included patients, 15 were treated with springs, and 16, with the conventional technique. Patients treated with springs had a significantly larger increase in skull circumference and anterior-posterior length, and not significant changes in blood loss compared with the conventional group. Complications in the conventional group were the following: minor dural tear in three patients, problematic wound healing in one patient, and insufficient expansion in one patient. Spring-related complications included skin perforation in two patients, a minor dural tear in two patients, and leakage of cerebrospinal fluid after an unnoticed dural tear during spring placement in one patient.

CONCLUSION

Spring-assisted posterior vault expansion has some advantages over the conventional technique and is, therefore, the preferred technique in our center.

Experience with craniosynostosis treatment using posterior cranial vault distraction osteogenesis

BACKGROUND

Craniosynostosis compromises the cranial vault volume, severely impede growth, and may lead to increased intracranial pressure (ICP). Posterior cranial vault (PCV) distraction osteogenesis (DO) offers an excellent treatment opportunity for this condition. This article intends to describe the outcomes of PCV DO.

MATERIALS AND METHODS

Nine males and seven female children indicated for PCV DO were included in the study. The single vector distraction devices with quick-disconnect distraction rods, a type of miniaturized hardware, was used in all cases.

RESULT

Seven of the 16 patients had a history of one or more prior cranioplasty. All reoperations in this series were performed for the indication of raised ICP including five of the scaphocephaly patients and the syndromic patients. Clinical signs of raised ICP were present in all patients with either measured raised intracranial pressure or those with clinical signs of raised ICP preoperatively. There was substantial decrease in the ICP postoperatively.

DISCUSSION

The outcomes of this study were encouraging. Placing the distractor stems as flat as possible against the outer layer of the cranial bone seems to be a very important maneuver. This keeps the distractor stem less proud and less likely to sustain future trauma. Removal of the distractor stems keeps the devices further away from the risk of later traumatic dislodgement. Moreover, miniaturized distractors allow precise control of the rate and the amount of distraction.

Spring-assisted correction of sagittal suture synostosis

PURPOSE

The purpose of this study is to describe the technique and advantages and limitations of spring-assisted cranioplasty for sagittal suture synostosis.

METHODS

Preliminary data are presented of the first 41 patients treated with this technique at our institution.

RESULTS

The cephalic index was 75 after surgery and dropped to 74 one year after surgery. Mean blood loss of both procedures combined was 54 ml.

CONCLUSION

Spring-assisted cranioplasty requires only two small incisions and is at least as effective as other techniques with respect to the cephalic index. Blood loss, operative time, and complication rate are reduced. The most important disadvantage is the need to remove the springs in a second intervention. A second drawback is that the expansion of the spring is not controllable after placement. This can be partially intercepted by adjusting the spring (or the craniotomy) to the patient's specific features.

Comparison of spring-mediated cranioplasty to minimally invasive strip craniectomy and barrel staving for early treatment of sagittal craniosynostosis

The treatment of sagittal craniosynostosis has evolved from early strip craniectomy to total cranial vault remodeling and now back to attempts at minimally invasive correction. To optimize outcomes while minimizing morbidity, we currently use 2 methods of reconstruction in patients younger than 9 months: spring-mediated cranioplasty (SMC) and minimally invasive strip craniectomy with parietal barrel staving (SCPB). The purpose of this study was to compare the safety and efficacy of the 2 methods. Hospital records of our first 7 SMCs and our last 7 SCPBs were analyzed for demographics, the type of operation performed, estimated blood loss, transfusion requirements, operative time, length of stay in the intensive care unit, length of hospital stay, preoperative cephalic index, postoperative cephalic index, and complications. The techniques were then compared using analysis of variance.All 14 patients successfully underwent cranial vault remodeling with significant improvement in cephalic index. Demographics, length of stay in the intensive care unit (P = 0.15), preoperative cephalic index (P = 0.86), and postoperative cephalic index (P = 0.64) were similar between SMC and SCPB. Spring-mediated cranioplasty had statistically significantly shorter operative time (P = 0.002), less estimated blood loss (P < 0.001), and shorter length of hospital stay (P = 0.009) as compared with SCPB. Complications included 1 spring dislodgment in an SMC that did not require additional management and 1 undercorrection in the SCPB group. Both SMC and SCPB are safe, effective means of treating sagittal craniosynostosis. Spring-mediated cranioplasty has become our predominant means of treatment of scaphocephaly in patients younger than 9 months because of its improved morbidity profile.

Time-dependent perioperative anesthetic management and outcomes of the first 100 consecutive cases of spring-assisted surgery for sagittal craniosynostosis

BACKGROUND

  The anesthetic risks and outcomes of the first 100 consecutive spring-assisted surgeries (SAS) for cranial expansion from a single institution are reported. The effect of number of procedures was also tested on hematocrit postoperative day 1 (POD1), anesthesia time, and surgery time of the first procedure.

METHODS

  The records of 100 consecutive patients undergoing SAS were reviewed. Anesthesia management and related complications are presented. Time series linear regression analysis was performed on hematocrit POD1, anesthesia time, and surgery time of the first procedure.

RESULTS

  The average age of the first insertion procedure was 4.4 and 9.0 months for the second removal procedure. Two patients were inadvertently extubated during positioning. Thirty-eight children had a decrease in blood pressure >20% from baseline. No child was admitted to the intensive care unit. No patient received any blood or blood product transfusion. Anesthesia time, surgery time, and hematocrit POD1 were correlated with procedure number or experience.

CONCLUSIONS

Changes in anesthetic management resulted from changing the procedure. The reduction in volume resuscitation reduces the need for invasive monitoring. Facility and comfort with the surgical procedure increase with time and number of procedures performed. This experience further reduces blood loss and risk of transfusion.

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.