Posterior Cranial Vault Distraction Research Articles

Management of Paronychia in Patients With Apert Syndrome.

Apert syndrome is a complex congenital syndrome that includes bicoronal craniosynostosis, craniofacial dysmorphologies, cleft palate, hearing loss, spina bifida occulta, cardiac anomalies, and affects the upper and lower extremities-producing complex syndactyly in these patients. Management of the hands yields several challenges and mandates close follow-up to balance repair of complex polysyndactyly with other pressing interventions, such as posterior cranial vault distraction and surgical management of the airway. Our goals of therapy for the hands are to preserve 10 digits, provide sufficient soft tissue coverage, optimize hand function, and minimize the number of surgical interventions. Ideally, surgical management of the hand differences occurs between the ages of 9 months and 2 years, to optimize neurocognitive development. In complex syndactyly observed in patients with Apert syndrome, there are broad, conjoined nail plates that overlie the fused digits, and paronychia occurs frequently. Suppurative infections can delay definitive surgical intervention for the patient's complex syndactyly, and resolution of paronychia is critical. This study aims to propose an effective and safe technique to manage paronychia when it occurs in patients with Apert complex syndactyly and to mitigate the length of delay to definitive polysyndactyly reconstruction. In the context of these patients' need for multiple surgical interventions within the first few years of life, this strategy for preventing or mitigating paronychia can play an important role in streamlining their complex surgical management while avoiding multiple cancellations.

S2-14 SESSION 2: POSTERIOR VAULT DISTRACTION QUANTITATIVE OUTCOMES IN POSTERIOR AND TRANSVERSE CRANIAL VAULT DISTRACTION FOR CRANIOSYNOSTOSIS

Introduction: CVD osteogenesis has been shown to establish greater cranial volume overall than conventional remodeling. Quantitative measurement with systematic evaluation of outcomes is vital for the comparison of surgical outcomes across international institutions. Computed tomography (CT) or magnetic resonance imaging (MRI) in addition to image analysis software has been increasingly used in recent times to predict ICV changes after cranial vault surgery. The primary study aim was to quantify ICV increase in CVD and secondarily to gauge acceptability of using a simple modality to measure ICV. Methods: A retrospective review of a prospectively maintained database of posterior and transverse cranial vault distraction procedures at the National Paediatric Craniofacial Centre in Temple Street Children’s University Hospital from May 2010 to September 2016 was performed. ICV was calculated using Osirix® Version 3.3 from post-operative CT-scans. Cephalometric analysis was also performed using lateral and anteroposterior radiographic views of the cranium. Data was analyzed with GraphPad Prism®. Results: 21 patients (9 PCVD and 13 TransCVD), underwent successful cranial vault distraction. Patients in the PCVD group achieved a mean ICV increase of 2947mm, 32.5% (range: 12.8% to 80.2%, p<0.0001).95% CI 2135 to 3758mm3. In the TransCVD group, an average ICV increase of 1912.96,15.8% (range: 4.4% to 24.2%, p<0.0001) was achieved. 95% CI 1507 to 2320 mm3. Cephalic index values moved towards normal range, average change of 10.1% (range: 2.04% to 19.83%, p<0.0552) in the PVD group and 6.8% in the TransCVD (range: 2.7% to 14.8%, p<0.0001) respectively. Conclusion: This institutional review of outcomes post cranial vault distraction for syndromic and non-syndromic synostosis contributes to the existing literature and confirms the satisfactory reliable results afforded by distraction surgery along with a favorable morbidity profile. Quantitative analysis of cranial vault expansion by distraction has shown a reproducible increase in total ICV and is an effective method for rapid expansion of ICV with normalization of head morphology. We found Osirix® used with CT scans an acceptable modality that does not compromise accuracy and confer excellent interactive user-software interface.

S4A-10 SESSION 4A: GENERALITIES IN CRANIOSYNOSTOSIS – PART I EFFECTS OF DIFFERENT DIRECTIONS OF ANTERIOR CRANIAL DISTRACTION OSTEOGENESIS ON ANTERIOR CRANIAL VOLUME

Introduction: Anterior cranial distraction osteogenesis has been proposed as an effective technique for expending the anterior cranial volume to avoid intracranial hypertension. Mostly studies have focused on volumetric changes in different surgical approaches such as fronto-orbital advancement and posterior cranial vault distraction osteogenes. However the direction of distraction can also affect the outcome. So the aim of this study was to analyze the effects of three different directions of anterior cranial distraction osteogenesis, these are 15 degrees forward and downward, horizontal distraction, 15 degrees forward and upward. Methods: This was a retrospective chart review performed between 2015 to 2018 at a the department of plastic surgery in the children`s hospital of Nanjing medical university. 24 patients were included in this study. We divided the patients into three groups according to the three directions of anterior cranial distraction osteogenesis. Each group has ten (10) patients. All the patients were performed the CT scan preoperatively and postoperatively. The CT databases were processed by DICOM files into MIMICS software, which were automatically calculated into anterior cranial volume. Then we calculated the percentage increase in anterior cranial volume of each group. Results: The mean increase volume was 64±17ml for 15 degrees forward and downward group 44±15 mlfor horizontal distraction group and 38±12ml for 15 degrees forward and upward group. The mean difference in anterior cranial volume between the 15 degrees forward and downward group and horizontal distraction group and 15 degrees forward and upward group was significantly increased (P <0.05) Conclusion: In this retrospective study, 15 degrees forward and downward group in anterior cranial vault distraction osteogenesis provided statistically greater anterior cranial volume expansion than the other two angles.

National 30-Day Outcomes for Posterior Cranial Vault Distraction.

Posterior vault distraction (PVD) can rapidly expand calvarial volume in infancy. Limited data exist regarding its perioperative and postoperative safety profile. This study sought to investigate the patient profile, outcomes, and safety of PVD using a national pediatric database. Posterior vault distraction patients between 2012 and 2016 were isolated from the National Surgical Quality Improvement Program Pediatric database. Patient background, perioperative outcomes, and risk factors were analyzed using chi-squared, t test analysis, and multivariate regression. Ninety-four patients who underwent PVD were isolated with 67 ultimately meeting inclusion criteria for the study. The majority of patients undergoing PVD had limited other documented comorbidities. No patients required reoperation or 30-day readmission. There were no incidences of stroke, surgical site infection, or death. Subdividing outcomes by specialty, plastic surgeons performed PVD on significantly older patients than neurosurgeons (188 days vs 138 days, P = 0.008). Increasing age was associated with increasing operative time (P < 0.001). Furthermore, increasing age is associated with greater absolute transfusion requirements (P = 0.018) and higher, but not significant, risk of requiring any volume of blood transfusion (P = 0.105). Posterior vault distraction is a safe procedure to rapidly expand calvarial volume in the setting of craniosynostosis. Increasing patient age is the strongest predictor for prolonged operative time and higher blood transfusion volumes.

Experience with resorbable sonic pins for the attachment of distraction devices in posterior cranial vault distraction operations

BackgroundDistraction techniques are effective methods for the treatment of craniosynostoses when a significant gain of an intracranial volume is required. However, this technique raises some challenges at different stages of the treatment. While installing the distractors in patients with thin calvarial bone, there is a risk of dural damage from the titanium screws. The need for wide exposure of the devices and the screws during removal causes soft tissue damage and bleeding.ObjectiveThis study aimed to evaluate sonic pin use in the distraction procedures.MethodsResorbable sonic pins were used in 11 consecutive posterior cranial vault distraction procedures to attach distraction devices to the calvarial bone.ResultsThis method allowed for a less traumatic and faster removal of the devices without the risk of leaving foreign bodies in the wound. In three out of 11 cases on follow-up, displacement of proximal distractor footplate and partial relapse of distraction were detected. Though there was a smaller volume increase in these patients, all of them benefited clinically from the PCVD and did not require reoperations.ConclusionsThis method allows a strong and stable attachment of the distractor devices to the cranial vault bones with a reduced risk of dural tears due to the screws. It also allows for easier and less traumatic device removal.

Quantitative Analysis of Change in Intracranial Volume After Posterior Cranial Vault Distraction and Frontal Orbital Advancement/Remodeling.

Patients with craniosynostosis with shortened occipitofrontal diameter are mainly treated with posterior cranial vault distraction osteogenesis (PVDO) in our institution. If further intracranial volume (ICV) expansion is needed, additional treatment with frontal orbital advancement (FOA) is done. On the contrary, frontal orbital remodeling (FOR) is done for better aesthetic results. In this study, post-treatment ICV changes in patients with craniosynostosis treated with these methods have been investigated. Patients who underwent FOA or FOR in addition to PVDO at Juntendo University Hospital between 2011 and 2017 were reviewed for patient characteristics and pre/postoperative ICV measurements using 3-dimensional computed tomography scans. Nine patients aged from 5 months to 6 years 8 months at the time of PVDO were included. For PVDO, the ICV change was 113 to 328 mL, and the enlargement ratio of ICV was 109% to 152%. Two patients were further operated with FOA while the remaining 7 with FOR. With FOA, ICV change was 73 to 138 mL, while enlargement ratio of ICV was 107% to 114%. With FOR, ICV change was 3 to 45 mL (mean 20 mL), while enlargement ratio of ICV was 100% to 103%. The PVDO is our first line of treatment for ICV expansion and posterior cranial fossa decompression in patients with severe craniosynostosis. The FOA is performed if extra ICV increase is necessary. This approach seems to enable larger ICV expansions compared with other conventional methods. The FOR should be reserved for patients in whom adequate ICV levels are achieved with PVDO yet additional frontal reshaping is necessary.

Increases in Cranial Volume with Posterior Cranial Vault Distraction in 31 Consecutive Cases

Posterior cranial vault distraction (PCVD) is a technique widely used in surgical treatment of craniosynostosis when cranial expansion is required. It has proven to be safe and to allow a significant increase of intracranial volume. To evaluate increases in intracranial volume as a result of PCVD performed in Oulu Craniofacial center using 2 different methods based on 3-dimensional (3-D) photogrammetric imaging or plain skull radiographs. All children less than 16 yr of age who were treated by PCVD (n = 31) from 2009 to 2015 at the Oulu Craniofacial Center were included. All patients were followed at outpatient clinics with plain radiographs performed for follow-up. In 5 patients, additional 3-D photogrammetric imaging was done pre- and postoperatively. The mean intracranial volume increase was 25.0%, ranging from 16.9% to 39.4%. In 5 patients, the increase in volume was calculated from the photogrammetric 3-D images comprising a mean of 17.4%. Volume calculations from cephalograms in the same patients gave a mean of 20.8%. Whether the distraction was a primary operation or patient had undergone previous cranioplasty did not influence the achieved volumetric results. There were no statistically significant differences in the distraction results between different diagnostic groups. PCVD is an effective surgical method to increase intracranial volume in a variety of clinical entities. Volumetric results of this procedure could be easily evaluated using 3-D photogrammetric imaging or plane radiographs that expose the patients to only low ionizing radiation doses.

Posterior cranial vault distraction osteogenesis in craniofacial surgery: Technical note

Posterior cranial vault distraction is a treatment for intracranial hypertension in certain cases of craniosynostosis and faciocraniosynostosis. It allows the harmonization of the skull back and prevents turricephaly. This study presents the surgical technique. Posterior cranial vault distraction osteogenesis consists of a circular osteotomy of the skull back. Four distractors are placed on the cranial flap without detachment of the dura mater. The distraction is carried out over nearly 1 month with an objective of 20mm. The technique's effectiveness is judged on the correction of the skull back shape and the disappearance of clinical and radiological signs of intracranial hypertension. Posterior cranial vault distraction osteogenesis enables a large increase in cranial volume and a correction of the dysmorphic skull back. This easy surgery and the low rate of complications make this technique a main surgical approach in the management of faciocraniosynostosis.

What's New in Syndromic Craniosynostosis Surgery?

After studying this article, the participant should be able to: 1. Understand the role of prenatal screening and counseling of parents of unborn children with syndromic craniosynostosis. 2. Recognize the genetic abnormalities, craniofacial phenotype, associated anomalies, and challenges associated with each of the five major forms of syndromic craniosynostosis. 3. Identify the pros and cons associated with timing and types of cranial vault remodeling techniques in this patient population. 4. Understand the risks and benefits associated with midface advancement with Le Fort III, Le Fort II plus zygomatic repositioning, monobloc, and facial bipartition. 5. Understand the important role of psychological counseling throughout childhood in this at-risk group. Crouzon, Apert, Pfeiffer, Muenke, and Saethre-Chotzen syndromes are the five most common forms of syndromic craniosynostosis. Although each has different genetic underpinnings and associated anomalies, their hallmark finding is turribrachycephaly most often associated with bicoronal craniosynostosis. The role of prenatal screening and counseling is growing, with caregivers becoming involved before birth. Multidisciplinary care from birth onward involves craniofacial plastic surgeons, neurosurgeons, otolaryngologists, ophthalmologists, orthodontists, anesthesiologists, psychologists, speech therapists, and geneticists. Early partial, or regional, craniectomy may be urgently indicated in multisuture cases with signs of increased intracranial pressure. Others may be managed successfully with posterior cranial vault distraction, middle vault expansion, or fronto-orbital advancement. Some authors have advocated early monobloc advancement for those patients who require acute airway intervention and globe protection, although the risks of these procedures are high. Many patients will require midfacial advancement with a Le Fort III, Le Fort II plus zygomatic repositioning, monobloc, or facial bipartition. The indications, risks, and benefits for each midfacial procedure must be considered, as this step in the treatment algorithm may carry the greatest functional and aesthetic benefits but also the potential for the greatest morbidity. At the culmination of facial growth, it is not uncommon for patients to require conventional orthognathic surgery and other bony contouring and soft-tissue procedures. Finally, an understanding of the psychological aspects of craniofacial difference, both in affected individuals and in their families, is essential to a successful, holistic approach.

Early Posterior Vault Distraction Osteogenesis for the Treatment of Syndromic Craniosynostosis.

Posterior cranial vault distraction (PCVD) has become an important modality in the management of complex craniosynostosis to increase intracranial volume and improve the cranial vault appearance. This technique can safely be performed as early as 3 months of age for the initial management of patients with complex craniosynostosis. A retrospective review was performed of all the patients with syndromic, multiple-suture synostosis treated with PCVD at Primary Children's Hospital in Salt Lake City, Utah, between 2012 and 2014. During this time period, a total of nine children with an average corrected age of 21.4 weeks were treated. Demographics, intraoperative data, and postoperative distraction data were collected. Occipital frontal head circumferences (OFCs) were recorded pre- and postdistraction, and at 3- and 6-month follow-up examinations. All patients had a substantial increase in head circumference with subjective improvement of the posterior calvarium shape. The average increase in OFC from preoperative to postdistraction was 4.9 cm. Only two significant postoperative complications were encountered, one hardware infection and one cerebrospinal fluid leak. PCVD is an effective procedure in the management of complex craniosynostosis and can be safely initiated very early in life.

Quantitative Analysis of Change in Intracranial Volume After Posterior Cranial Vault Distraction.

Posterior cranial vault distraction is considered to be more effective for increasing intracranial volume than fronto-orbital advancement or anterior cranial vault expansion, but the changes in intracranial volumes after posterior cranial vault distraction remain unclear. The changes in intracranial volume were investigated in patients of premature craniosynostosis treated by this technique. Seven patients, 3 boys and 4 girls aged from 5 months to 3 years 3 months (mean 23 months) at operation, with craniosynostosis underwent posterior cranial vault distraction at Juntendo University Hospital from 2011 to 2014. Patient characteristics, length of distraction, and pre- and postoperative computed tomography findings were reviewed. Total intracranial volume, including the supratentorial space and posterior cranial fossa, was measured using the workstation functions on three-dimensional computed tomography scans. Posterior distraction was performed without severe complications except in 2 patients requiring additional surgeries. The distraction length was 22.3 to 39 mm (mean 31 mm), the intracranial volume change was 144 to 281 mL (mean 192 mL), and the enlargement ratio of intracranial volume was 113% to 134% (mean 121%). The present quantitative analysis of intracranial volume change after posterior distraction showed greater increases in intracranial volume compared with previous reports. Furthermore, intracranial volumes in our patients became nearly normal and were maintained for the follow-up period (maximum 13 months). Posterior cranial vault distraction is very effective to increase cranial volume, so may be the first choice of treatment in patients of craniosynostosis.

A New Technique for Posterior Distraction in Craniosynostosis

Posterior cranial vault distraction osteogenesis is a common treatment for syndromal patients of brachycephaly and oxycephaly. Although posterior distraction can increase intracranial volume, the flattened head phenotype is difficult to correct. The authors examined a new posterior distraction technique termed double-door distraction for improvement of the flattened head phenotype. From 2010 to 2013, 6 patients with flattened posterior craniums were operated on using the double-door distraction technique. The calvarial segment was cut at the midline and divided into 2 pieces. Distractors were then fixed in parallel to join the calvarial pieces. The distraction was initiated at a rate of 1.0 mm/day and continued until proper cranial form was confirmed by radiography and appearance. The average surgery time was 2 hours 47 minutes and the amount of distraction ranged from 15 to 22 mm. An improved head shape and expanded cranial vault was achieved in all patients without any complications. The double-door distraction technique is a useful technique not only for calvarial expansion, but also for correction of the flattened posterior cranium phenotype.

Wire fixation of internal distractor for cranial vault remodeling.

Posterior cranial vault distraction osteogenesis is currently used to enlarge the cranial volume and control the intracranial pressure. This procedure carries the risk of hardware dislocation, and especially in infants, as their skull being thin, the screws may damage the underlying dura. In this paper, the authors describe a simple method to fixate the internal distractor to the skull vault in case of thin calvaria using metallic wires. This method allows a strong and tight application of the distractor to the osteotomy margins and reduces the risks of loosening of the device and the risk of dural tears. It is particularly useful in young children or in case of diffuse digitate impressions with areas of reduced thickness of the skull bone.

Complications in Posterior Cranial Vault Distraction.

The use of posterior cranial vault distraction for the treatment of elevated intracranial pressure is gaining popularity and is a standard for first-stage cranial expansion in syndromic craniosynostosis at many institutions. However, although the operation is faster and less complex than other cranial vault remodeling procedures, it is not without its own unique set of complications. We surveyed the published literature for case series and case control studies on posterior vault distraction. Complication rates and types for these series were tabulated and grouped by management. When outcomes were unclear, corresponding authors were contacted for clarification and treatment plans. Eleven reports were found from a search of all the literature on posterior cranial vault distraction with a range of 1 to 22 included patients. The average age at surgery was 16.2 ± 11.8 months. Complication rates ranged from 12.5% to 100%, with the average of 30% of patients across all studies. The most common complications reported were cerebrospinal fluid leak or dural injury, followed by wound infections or device exposures, and device failure. There were no reported patient deaths or long-term morbidities. Posterior cranial vault distraction is a relatively safe and effective therapy for the treatment of elevated intracranial pressure in the setting of syndromic craniosynostosis. The majority of described complications center on the interaction of the device with the dura, device extrusion, and infection. Extreme care must be used with the placement of these distraction devices and with handling of the dura at the osteotomy sites to ensure successful outcomes and avoid complications. III.

Inferiorly-Directed Posterior Cranial Vault Distraction for Treatment of Chiari Malformations

PURPOSE: Chiari I malformations involve a small posterior fossa and subsequent herniation of the hindbrain, causing altered cerebrospinal fluid flow and intracranial hypertension (Figure 1). Traditional decompressive management uses a posterior fossa craniectomy, which carries limitations and complication risks, including over-correction or the need for re-operation. A large single-stage craniectomy can lead to cerebellar ptosis and new or recurrent symptoms. Distraction of the posterior vault has been effective for relieving intracranial pressure in small case series.1,2 The authors present the largest series of patients with Chiari I malformations treated with posterior cranial vault distraction osteogenesis. Also introduced is a previously unpublished technique utilizing a vertical distraction vector for vault expansion while mitigating the risks of scaphocephaly and cerebellar ptosis.Figure 1: Pre-operative MRI.METHODS: This multi-center study included patients with syndromic and non-syndromic Chiari I malformations treated with vertical-vector distraction osteogenesis of the posterior cranial vault from 2008 to 2014. All patients had follow-up of at least 1 year except one who recently completed the full protocol. Demographics, pre- and post-operative clinical symptoms, and perioperative details were assessed. Postoperative aesthetics, complications, and symptomatic improvement were evaluated with neurosurgery. RESULTS: Nine patients were identified. Five had known syndromes, two likely had unidentified syndromes, and two were non-syndromic. Seven had prior Chiari-related surgeries. Most presented with hydrocephalus, motor symptoms, and developmental delay. Operatively, internal distraction fixators were applied with the distraction vector following a cephalad-caudad axis. Devices were activated on POD5 and distracted 1 mm/day. Three post-operative complications included a dislodged distraction arm, device extrusion, and local cellulitis. No complications affected the clinical outcome. All patients completed the distraction protocol. Radiographic follow-up showed good bone formation, posterior fossa decompression, improved CSF flow, and no cerebellar ptosis (Figure 2). Neurological surveillance showed improvement in intracranial pressure, hydrocephalus, motor symptoms, and behavioral problems. Importantly, with average follow-up of 3.5 years, no patient required reoperation for persistent or recurrent symptoms.Figure 2: Post-Operative MRI.CONCLUSION: The authors have presented the largest experience to date of Chiari I malformations treated with distraction osteogenesis, along with a novel technique to safely and effectively expand the posterior fossa while minimizing risk of cerebellar ptosis, scaphocephaly, and reoperations. With excellent functional, aesthetic, and clinical outcomes from this technique, it appears valuable as an initial or secondary operation for symptomatic Chiari I malformations.

Posterior Cranial Vault Distraction Osteogenesis with Barrel Stave Osteotomy in the Treatment of Craniosynostosis.

Twenty years have passed since distraction osteogenesis was introduced into the field of craniomaxillofacial surgery, with distraction osteogenesis gradually consolidating its position for midface advancement in syndromic craniosynostosis. On the other hand, no consensus has been reached regarding its adaptation to calvarial bone. We reported that distraction osteogenesis was useful in posterior cranial vault expansion, and subsequently, similar reports have been successively observed worldwide. In posterior cranial vault distraction, intracranial capacity could be greatly expanded due to its simultaneous expansion with the scalp, with little risk of relapse because new bone is regenerated in the distraction gap. The possibility was suggested that the standard of first carrying out fronto-orbital advancement (FOA) for brachycephaly observed in syndromic craniosynostosis will greatly change posterior cranial vault distraction.

Posterior cranial vault distraction in the management of syndromic multi-suture craniosynostosis: Outcomes and 3d photographic/ct-based morphometric analysis

Posterior cranial vault distraction in the management of syndromic multi-suture craniosynostosis: Outcomes and 3d photographic/ct-based morphometric analysis

Lessons learned in posterior cranial vault distraction.

Posterior distraction (PD) is rapidly emerging as an important technique to increase the intracranial volume and correct calvarial morphology in patients with severe brachycephaly or turribrachycephaly. A retrospective review was performed of all 31 patients who underwent PD at the Oxford Craniofacial Unit between 2007 and 2012. Twenty-three patients (74.2%) underwent PD as a primary procedure at a median age of 8 months. Eight patients (25.8%) had PD as a secondary transcranial procedure at a median age of 48 months. Full distraction to 20 mm was achieved in 28 patients (90.3%). Of these, all but 1 demonstrated a significant improvement in morphology, with a resolution of the symptoms and signs of raised intracranial pressure in all proven to have it preoperatively. Unanticipated events occurred in 61.3% of patients, with 19.4% undergoing one or more unplanned procedures. Wound infection (29.0%) and tissue necrosis (22.6%) were the commonest. Cerebrospinal fluid leaks were rarer (6.5%) but prevented full distraction. Nine patients (29.0%) had a consolidation period of less than 30 days without experiencing relapse. In 11 patients who had a later fronto-orbital advancement and remodeling, wound closure was tight, resulting in dehiscence in 3 cases (27.3%). Posterior distraction is an effective procedure in the management of severe brachycephaly or turribrachycephaly but has associated risks. Our protocol has evolved with experience to favor a reduced latency period and consolidation phase and the use of 2 distractor devices.

A Craniometric Analysis of Posterior Cranial Vault Distraction Osteogenesis

Posterior cranial vault distraction osteogenesis has replaced fronto-orbital advancement in some centers as the first-line treatment in patients with syndromic craniosynostosis. Despite this fact, little has been written about its craniometric effects on children with syndromic craniosynostosis. A retrospective review of all patients who underwent posterior distraction was performed. Patient demographic, perioperative data, and preoperative/postoperative computed tomographic scans were reviewed. Volumetric and craniometric indices were calculated and measured using commercial three-dimensional imaging software. From 2008 to 2012, 22 patients underwent posterior vault distraction osteogenesis for suspected intracranial hypertension or severe turribrachicephaly. In 13 patients, this was the first cranial vault procedure performed, whereas eight had previous fronto-orbital advancement and one had parieto-occipital reshaping. Half of patients underwent posterior cranial vault distraction osteogenesis before age 1 year; the average age at surgery was 2.3 years (range, 0.3 to 14.1 years) and distraction length averaged 27.3 mm (range, 19 to 35 mm). Average length of surgery was 2.9 hours (range, 1.6 to 3.8 hours), and average blood loss was 400 ml (range, 200 to 600 ml). Total treatment length was 91 days (range, 48 to 147 days). Distraction length averaged 27.3 mm (range, 19 to 35 mm). Intracranial volume increase averaged 21.5 percent (range, 7.5 to 70.0 percent; p<0.0001) and 28.4 percent (range, 10.8 to 66.0 percent; p=0.01) in the subset of patients younger than 1 year. Posterior cranial height increased 12.2 percent (range, 0 to 35 percent; p=0.002), and basofrontal angle decrease averaged 3.9 percent (range, 0 to 12 percent; p=0.003), indicating a decrease in cranial height trajectory and improvement in frontal bossing. Posterior cranial vault distraction is a safe and effective operation that may lower risk of intracranial hypertension and abnormal skull morphology. Interestingly, cranial morphological benefits were seen both anteriorly and posteriorly. Therapeutic, IV.

Expanding Indications and Device Refinement in Posterior Cranial Vault Distraction Osteogenesis

Introduction: Expansion of the posterior cranial vault can be used to treat cephalocranial disproportion and cranial vault dysmorphology. Posterior cranial vault distraction osteogenesis has been described in syndromic patients with craniosynostosis as a viable method for expanding the posterior cranial vault, and has potential advantages over traditional expansion. The purpose of this study was to demonstrate the utility of posterior cranial vault distraction osteogenesis for treating a variety of craniosynostosis and cranial vault anomalies, as well as to review the development of a cranial-specific distraction device.