Pediatric Cranial Vault Research Articles

Pediatric Cranial Vault and Skull Base Fractures.

Cranial vault and skull base fractures in children are distinctly different from those seen in adults. Pediatric skull fractures have the benefit of greater capacity to remodel; however, the developing pediatric brain and craniofacial skeleton present unique challenges to diagnosis, natural history, and management. This article discusses the role of surgical treatment of these fractures, its indications, and techniques.

Autologous Cranioplasty Using a Dental SafeScraper Device.

Conventional methods to reconstruct cortical bone defects introduced by pediatric cranial vault remodeling (CVR) procedures have shortcomings. Use of bone burr shavings as graft material leads to variable ossification, and harvesting split-thickness cortical grafts is time-intensive and often not possible in thin infant calvaria. Since 2013, the authors' team has used the SafeScraper, originally developed as a dental instrument, to harvest cortical and cancellous bone grafts during CVR. The authors assessed the effectiveness of this technique by analyzing postoperative ossification using computed tomography scans of 52 patients, comparing cohorts treated with the SafeScraper versus those who received conventional methods of cranioplasty during fronto-orbital advancement. The SafeScraper cohort had a greater reduction in total surface area of all defects (-83.1% ± 14.9 versus -68.9% ± 29.8; P = 0.034), demonstrating a greater and more consistent degree of cranial defect ossification compared with conventional methods of cranioplasty, suggesting potential adaptability of this tool. This is the first study that describes the technique and efficacy of the SafeScraper in reducing cranial defects in CVR. Therapeutic, III.

Three-Dimensional Printed Polycaprolactone Mesh in Pediatric Cranial Vault Remodeling Surgery.

The surgical management of craniosynostosis has greatly evolved with improvements in both technology and understanding of the disease process. Some drawbacks remain regarding bone regeneration within the surgical bony gaps. Generally, bony gaps improve in the 12 to 24 months after surgery, but some gaps may remain for longer and cause deformity and/or require additional bony reconstruction. These considerations make tissue-engineered bone very attractive. Novel 3-dimensional printed bioresorbable mesh implants made of Polycaprolactone (PCL) can be used to fill the surgical bony defects. The authors seek to investigate how the use of a 3-dimensional printed biodegradable PCL mesh applied to bony defects in cranial vault surgery affects bone healing. Case series analysis of 8 pediatric patients who have undergone surgical intervention using PCL mesh implants for reconstruction of bony defects during craniosynostosis correction surgery. Radiological evaluation of 3 patients at random time points between 9 and 12 months postoperative revealed persistent bony gaps in areas where PCL mesh was laid. One patient who underwent a subsequent cranial vault surgery at 9 months was found to have less bone regeneration in the defect area where PCL mesh was used when compared with an adjacent area where a particulate bone graft was used. Based on our experience, the use of PCL mesh on its own did not augment bone regeneration. It is possible that a greater amount of time or increased vascularization of the scaffold is required, which supports the concept of regenerative matching axial vascularization or the further addition of osteogenic factors to increase the rate of bone formation.

Perioperative Outcomes Following Pediatric Cranial Vault Remodeling: Are Improvements Possible?

The Pediatric Craniofacial Collaborative Group recently reported pooled perioperative data from 31 North American centers performing open cranial vault remodeling procedures. The authors sought to determine if outcomes were different at a single higher-volume center and if identified, ascertain reasons for any differences and propose strategies for improvement. A retrospective review was performed of all open pediatric cranial vault procedures performed at our center during the identical 3.25-year period reported by the Collaborative group, including demographic, perioperative management and outcome data, to permit multiple comparative analyses. The 310 procedures were performed by our center during this time period, compared to 1223 by the combined 31 institutions (median: 29.5 cases/center; interquartile range: 12-54.5). Multiple outcome differences were found: our higher-volume center had a significantly lower overall red blood cell transfusion rate (≤2 years: 7.5 percent vs 91 percent, P <0.001), those requiring transfusions were transfused considerably smaller volumes (≤2 years: 3.8mL/kg vs 45.3 mL/kg, P <0.001), and exposure to ≥3 blood donors was significantly less (none vs 20 percent, P <0.001). There were no mortalities in either group, but almost all matched adverse events were less common at our center. Both the intensive care unit and hospital lengths of stay were significantly shorter at our center (1 vs 2 days, 2 vs 4 days, both P <0.001). Perioperative outcomes following pediatric craniosynostosis corrections performed at a single higher-volume center compare favorably to median national data. Multiple potential strategies to reduce blood utilization, minimize perioperative complications, and shorten hospitalizations are proposed.

Safety of antifibrinolytics in cranial vault reconstructive surgery: a report from the pediatric craniofacial collaborative group.

Antifibrinolytic therapy significantly decreases blood loss and transfusion in pediatric cranial vault reconstructive surgery; however, concern regarding the side effects profile limits clinical use. The aim was to utilize the Pediatric Craniofacial Surgery Perioperative Registry database to identify the safety profile of antifibrinolytic therapy for cranial vault reconstructive surgery by reporting the incidence of adverse events as they relate to exposure to tranexamic acid and aminocaproic acid compared to no exposure to antifibrinolytics. The database was queried for cases of open cranial vault reconstructive surgery. Less invasive procedures such as neuro-endoscopic and spring-mediated cranioplasties were excluded. The outcomes evaluated included any perioperative neurological adverse event including seizures or seizure-like movements and thromboembolic events. Thirty-one institutions reported a total of 1638 cases from 2010 to 2015. Total antifibrinolytic administration accounted for 59.5% (tranexamic acid, 36.1% and aminocaproic acid, 23.4%), with 40.5% not receiving any antifibrinolytic. The overall incidence of postoperative seizures or seizure-like movements was 0.6%. No significant difference was detected in the incidence of postoperative seizures between patients receiving tranexamic acid and those receiving aminocaproic acid [the odds ratio for seizures being 0.34 (95% confidence interval: 0.07-1.85) controlling for American Society of Anesthesia (ASA) physical class] nor in patients receiving antifibrinolytics compared to those not administered antifibrinolytics (the odds ratio for seizures being 1.02 (confidence interval 0.29-3.63) controlling for ASA physical class). One complicated patient in the antifibrinolytic group with a femoral venous catheter had a postoperative deep venous thrombosis. This is the first report of an incidence of postoperative seizures of 0.6% in pediatric cranial vault reconstructive surgery. There was no significant difference in postoperative seizures or seizure-like events in those patients who received the tranexamic acid or aminocaproic acid vs those that did not. This report provides evidence of the safety profile of antifibrinolytic in children having noncardiac major surgery. Caution should prevail however in using antifibrinolytic in high-risk patients. Antifibrinolytic dosage regimes should be based on pharmacokinetic data avoiding high doses.

Clinical Characteristics of Benign Pediatric Cranial Vault Tumors: Surgical Considerations Based on 100 Cases

Background/Aims: Tumors of the cranial vault occur at every age of childhood. Although they are mostly benign lesions, their symptomatology is variable and requires extended diagnostics. The choice of therapeutic strategy strongly depends on histopathological diagnosis, and therefore surgical excision is the elective treatment in such cases. Despite several published papers, the literature still lacks reliable clinical characteristics regarding this heterogeneous group of lesions in pediatric patients. Methods: We present a series of 100 children (55 male, 45 female) with scalp and cranial vault masses (average age: 3.6 years; range: 1 month to 17 years). Eighty-three (83%) patients underwent surgical excision. Demographic data, clinical presentation, diagnostic studies, choice of therapy, and the results of treatment were evaluated. Results: All removed tumors were benign pathologies: pilar cysts (30%), epidermoid/dermoid cysts (21%), vascular malformations (11%), inflammatory tumors (5%), and dysraphic remnants (2%). However, underlying bone destruction was observed in 61% of cases. Cranial extension occurred in 34%. Recurrence was noted in 1 case. Conclusions: Cranial vault tumors are characterized by constant growth and may penetrate the cranial cavity. Delayed surgery increases the risk of intracranial complications. Surgical problems include inappropriate planning, higher risk of intraoperative bleeding, and the need for subsequent cranioplasty.

Implementation of a Tranexamic Acid Protocol to Reduce Blood Loss During Cranial Vault Remodeling for Craniosynostosis

Pediatric cranial vault remodeling for repair of craniosynostosis is associated with significant blood loss and transfusion requirements. Beginning in 2011, the authors evaluated the impact tranexamic acid (TXA) on blood loss and blood product transfusion for children less than 15 months of age undergoing primary surgical repair of nonsyndromic single suture craniosynostosis. Following institutional review board approval, the authors performed a retrospective study of all children undergoing surgical correction of craniosynostosis at Oregon Health & Science University from 2005 to 2015. All available records were reviewed, and patient data were collected from the time of preoperative evaluation until discharge, comparing patient and clinical variables before and after the implementation of perioperative TXA. Of a total of 259 patients with craniosynostosis, 187 had nonsyndromic single-suture involvement; 69 of these patients (36.9%) received TXA. A single surgical team (AAK and NRS) performed all operations. Median age at the time of surgery was 8.1 months (interquartile range [IQR] of 6.0-9.8 months). The TXA group had a significant reduction in estimated intraoperative blood loss (26 mL/kg versus 36 mL/kg, P <0.001), cell saver volume transfused 6 mL/kg versus 10 mL/kg, P <0.001), red cell transfusion volume (32 mL/kg versus 42 mL/kg, P <0.001), exposure to plasma transfusion (0% versus 24% P <0.001), exposure to cryoprecipitate transfusion (0% versus 16%, P <0.001), and exposure to platelet transfusion (0% versus 7.6% P = 0.03). Despite reduced red cell transfusion, the TXA-treated patients exhibited similar postoperative hematocrits (30.4 versus 30.3 P = 0.906) to those not treated with TXA. Use of TXA was associated with reduced length of stay (4 days IQR 3-4 versus 4 days IQR 4-5, P <0.001) and reduced postoperative output from surgically placed drains (181 mL versus 311 mL P <0.001). There was no difference in postoperative complications between groups and no deaths in either group. The introduction of TXA for nonsyndromic single-suture synostosis repair at our institution has significantly reduced blood loss and blood product and plasma transfusion during and following primary cranial vault remodeling for single suture craniosynostosis. Postoperative hematocrit was similar in the TXA-treated and untreated groups despite reduced red cell transfusion in the treated group. In addition, TXA use in this population has eliminated the need for plasma transfusion, and is associated with a shorter hospital stay. No difference in postoperative complications was observed. Our data provide support for further investigation of TXA treatment to improve clinical outcomes in children undergoing pediatric cranial vault remodeling.

Use of tranexamic acid in craniosynostosis surgery

Background Intraoperative tranexamic acid (TXA) administration has been used to abate blood loss in a variety of surgical procedures. Several recent studies have supported its efficacy in reducing transfusion requirements in pediatric cranial vault reconstruction (CVR). Objective To conduct a retrospective chart review to determine whether a significant reduction in packed red blood cell (PRBC) and fresh frozen plasma (FFP) transfusions exists when TXA is used. Methods A retrospective cohort study of 28 patients who underwent CVR for sagittal craniosynostosis was performed. Transfusion requirements for 14 patients who did not receive TXA were compared with 14 patients who did. Predictors of increased blood product transfusion were also studied. Results Total volume of PRBC transfusion was reduced by 50% with the use of TXA (P=0.004) with a 34% reduction in intraoperative PRBC transfusion (P=0.017) and a 67% reduction in postoperative PRBC transfusion (P&lt;0.001). Total volume of FFP transfusion was reduced by 46% (P=0.002) and postoperative FFP transfusion was reduced by 100% (P=0.001). The use of TXA was associated with a lower total volume of PRBC (P=0.003) and FFP (P=0.003) transfusions. Older patient age was associated with lower total volume of PRBC transfused (P=0.046 and P=0.002), but not with FFP (P=0.183 and P=0.099) transfusion volumes. Increasing patient weight was associated with lower PRBC (P=0.010 and P=0.020) and FFP (P=0.045 and P=0.016) transfusion volumes. Conclusion TXA decreased blood product transfusion requirements in patients undergoing CVR for sagittal craniosynostosis, and should be a routine part of the strategy to reduce blood loss in these procedures.

Use of tranexamic acid in craniosynostosis surgery.

Intraoperative tranexamic acid (TXA) administration has been used to abate blood loss in a variety of surgical procedures. Several recent studies have supported its efficacy in reducing transfusion requirements in pediatric cranial vault reconstruction (CVR). To conduct a retrospective chart review to determine whether a significant reduction in packed red blood cell (PRBC) and fresh frozen plasma (FFP) transfusions exists when TXA is used. A retrospective cohort study of 28 patients who underwent CVR for sagittal craniosynostosis was performed. Transfusion requirements for 14 patients who did not receive TXA were compared with 14 patients who did. Predictors of increased blood product transfusion were also studied. Total volume of PRBC transfusion was reduced by 50% with the use of TXA (P=0.004) with a 34% reduction in intraoperative PRBC transfusion (P=0.017) and a 67% reduction in postoperative PRBC transfusion (P<0.001). Total volume of FFP transfusion was reduced by 46% (P=0.002) and postoperative FFP transfusion was reduced by 100% (P=0.001). The use of TXA was associated with a lower total volume of PRBC (P=0.003) and FFP (P=0.003) transfusions. Older patient age was associated with lower total volume of PRBC transfused (P=0.046 and P=0.002), but not with FFP (P=0.183 and P=0.099) transfusion volumes. Increasing patient weight was associated with lower PRBC (P=0.010 and P=0.020) and FFP (P=0.045 and P=0.016) transfusion volumes. TXA decreased blood product transfusion requirements in patients undergoing CVR for sagittal craniosynostosis, and should be a routine part of the strategy to reduce blood loss in these procedures.

Tranexamic Acid reduces blood loss and blood product use during pediatric cranial vault remodeling

RESULTS: A total of 210 patients were identified, 47 were treated with TXA. No difference in preoperative characteristics between groups was identified; average age at time of surgery was 9 months. Estimated blood loss was significantly reduced in the TXA group (33.4 vs 40.6 ml/kg p<0.01), as was red cell transfusion volume (38.8 vs 46.1 ml/kg p<0.01). In the TXA group the need for plasma/cryoprecipitate transfusion was reduced (4% vs 35% p<0.01). No significant difference in vasopressor use was found (6% vs 6% p1⁄40.97). TXA treated patients exhibited higher postoperative hematocrits (33.0 vs 30.9 p<0.01), and decreased drain output (173 vs 344 ml p<0.01). No differences in mortality, length of stay, or post-operative complications were seen between groups.

New Resorbable Plate and Screw System in Pediatric Craniofacial Surgery

Early forms of resorbable fixation induced foreign body reactions requiring surgical removal of the fixation material. Most current plating systems attempt to circumvent this phenomenon by altering the composition of the α esters involved. ResorbX (KLS Martin, Jacksonville, FL), a plating system derived from 50:50 poly(D,L)lactide, boasts short resorption times, minimal foreign body reaction, and adequate strength for bony fixation. We present our experience with 134 patients undergoing correction of primary craniosynostosis, using ResorbX. One hundred thirty-four consecutive craniosynostosis patients underwent correction with calvarial remodeling by the senior author between April 2002 and March 2008. Five patients had 2-stage repairs. Postoperative analysis included plate visibility or palpability, head contour, and the incidence of complications. The mean age at repair was 17.0 months, with the median age being 9.0 months (range, 2.5-137 months). Postoperative follow-up visits were recorded at 3-month intervals from 0 to 24 months. Synostosis diagnoses were as follows: 43 metopic, 37 sagittal, 27 coronal, 5 lambdoid, and 27 multisutural synostosis. There were 3 complications requiring operative intervention. Three plates became exposed through the coronal excision, requiring removal, for an overall complication rate of 2%. Forty-four patients (31.7%) had a visible mass at the site of fixation at some point postoperatively; all of these resolved through observation only. Overall postoperative head aesthetics were deemed satisfactory to excellent, and no instances of contour regression occurred. This study documents the safety and efficacy of ResorbX in pediatric cranial vault remodeling. The system is easy to use, and with the advent of an ultrasonic pin, more abbreviated operating and anesthesia times are achievable.

Pediatric Cranial Vault Defects

Pediatric calvarial defects may result from numerous causes. Availability of bone is often limited because of the child's age, and bone substitutes may be needed to reconstruct the defects. A bone substitute composed of ultraporous beta-tricalcium phosphate (Orthovita, Malvern, PA) is an osteoconductive product successfully used in orthopedic surgery. However, its application in cranial vault reconstruction is largely unstudied. The purpose of this investigation was to determine the healing rate of bone defects with the use of this product.A retrospective review was performed of patients in whom beta-tricalcium phosphate was used. Patient population consisted of 23 patients. Mean surgical age was 35 months. Reconstructions consisted of 20 craniosynostosis corrections and 3 posttraumatic repairs. The average defect size was 37 cm (range, 4.6-210 cm). Average follow-up was 12.7 months.At 2 months, 19 (79%) of 23 patients achieved healing of their defect, defined as the absence of persistent bone gaps. Persistent areas of bone weakness occurred in 3 patients at 4 months and 2 patients at 6 months. By 9 months, only 1 patient had not healed. This patient had the largest original defect of 210 cm. Defects taking longer than 2 months to heal measured 83 cm, whereas healed defects were 32 cm. No patients required treatment for graft-related problems such as infection or exposure.Early experience with beta-tricalcium phosphate bone substitute shows good healing of pediatric calvarial vault defects by 2 months, with no graft-associated complications. It seems most effective in the repair of smaller defects less than 40 cm.

Adipose-Derived Stem Cell Osteogenesis for Repair of the Pediatric Cranial Vault

Adipose-Derived Stem Cell Osteogenesis for Repair of the Pediatric Cranial Vault

Reducing allogenic blood transfusions during pediatric cranial vault surgical procedures: a prospective analysis of blood recycling.

Almost all patients who undergo major craniosynostosis corrections receive allogenic blood transfusions. This study of intraoperative blood salvage was undertaken in an attempt to further reduce the need for blood transfusions and to enhance the safety of these complex procedures. This prospective nonrandomized series included 60 consecutive children undergoing major cranial vault remodeling, primarily for treatment of craniosynostosis (single-suture and syndromic). A single craniofacial surgeon performed all operations, using a cell-saver equipped with a 55-cc pediatric bowl. The average age of the patients in this series was 4 years (33 of 60 patients were less than 18 months of age), and the average length of the surgical procedure was 196 minutes. Fifty-three percent were primary procedures and 47 percent were secondary. The mean estimated blood loss was 356 cc (19 cc/kg, or 28.5 percent of the estimated total blood volume). An average of 110 cc of cell-saver blood (range, 5 to 900 cc), or 7.8 percent of the patient's estimated total blood volume (approximately 15 percent, accounting for hemoconcentration of the cell-saver blood), was recycled for transfusion. No statistically significant factors (primary versus secondary procedure, diagnosis, age, or weight) were identified as predictive indicators for the use of this technology. Although 59 of 60 patients received transfusions, only 18 (30 percent) received allogenic blood (average, approximately 140 cc). There were no complications associated with the use of the cell-saver device. Use of the cell-saver during major craniosynostosis repair seemed to be safe and was associated with an extremely low allogenic blood transfusion rate.

Use of resorbable and screw fixation in pediatric craniofacial surgery

The concept of a rigid but nonpermanent method for bone stabilization for craniomaxillofacial surgery, particularly in infants and children, has long had theoretical appeal but a safe and effective method for bone fixation has been wanting. Since 1996, resorbable plate and screw systems have been available for clinical use. In this review, the author's technique and experience over the past 8 years for fixation of pediatric cranial vault deformities with one specific type of resorbable biomaterial, polylactic-polyglycolic acid copolymer (LactoSorb), biomaterial is described. The evolution of device use including conventional plate geometries, mesh panels, extended plate designs, threaded screws, push screws, and rivets is reviewed.