David Y. Khechoyan

History of synthetic materials in alloplastic cranioplasty

When faced with calvarial defects, surgeons have long searched for repair materials. General criteria include ease of use, low cost, availability, cosmetic shape, and osteointegrative potential. While autologous bone is widely used and favored in contemporary reconstructive procedures, synthetic alternatives have been used throughout history and are necessary in current practice for select cases when autograft reconstruction is not an option (such as cases with severe bony comminution, bone graft resorption, infection, and limited donor site options). For centuries, surgeons have experimented with metals, ceramics, plastics, and later, resorbable polymers. This paper provides a tour of the materials that have been used and experimented with throughout the history of alloplastic cranioplasty.

Surgical outcomes in craniosynostosis reconstruction: The use of prefabricated templates in cranial vault remodelling

Cranio-orbital reshaping for anterior cranial-vault deformities associated with craniosynostosis traditionally relies on the surgeons subjective estimate of the shape and appearance of a normal forehead. Computer-aided design/computer-aided manufacture (CAD/CAM) bandeau templates to guide reconstruction were introduced in our centre to eliminate this subjectivity and to effect more reproducible surgical results. The aim of this study was to compare two groups of patients (template, n = 14 vs. no template, n = 23) to measure surgical outcomes. The virtual, computational version of the template was used as an outcome assessment tool. It was used to calculate an intervening area under the curve (AUC) between the normative template and the patients reconstructed supra-orbital bar on a representative computed tomography (CT) axial section. A comprehensive chart review was conducted of patients in both groups to examine the preoperative and postoperative variables. Based on the analysis performed on the immediate postoperative CT scans, in the template group - as compared to the control, no-template group - the use of the bandeau template led to a greater reduction in AUC (74% vs. 56%, p = 0.016), indicating a better conformity between the reconstructed supra-orbital bar and the ideal, normal bandeau shape. The duration of operation was significantly reduced with the use of the template (212 vs. 258 min, p < 0.001). The application of prefabricated templates in cranio-orbital reshaping is highly useful for accurate preoperative planning; reproducible and efficient intra-operative correction of dysmorphology; and objective surgical outcomes assessment.

Prenatal Identification of Pierre Robin Sequence: A Review of the Literature and Look towards the Future

Fetal ultrasonography is an important tool used to prenatally diagnose many craniofacial conditions. Pierre Robin sequence (PRS) is a rare congenital deformation characterized by micrognathia, glossoptosis, and airway obstruction. PRS can present as a perinatal emergency when the retropositioned tongue obstructs the airway leading to respiratory compromise. More predictable and reliable diagnostic studies could help the treating medical team as well as families prepare for these early airway emergencies. The medical literature was reviewed for different techniques used to prenatally diagnose PRS radiologically. We have reviewed these techniques and suggested a possible diagnostic pathway to consistently identify patients with PRS prenatally.

Cephalometric outcomes of orthognathic surgery in hemifacial microsomia.

Abstract Hemifacial microsomia is a hypoplastic disorder of the first and second branchial arches that significantly impacts on the development of the jaws, leading to malocclusion and facial asymmetry. There is little in the literature regarding the application of orthodontic/orthognathic approaches to the correction of these deformities and the stability of the surgical results. To address this, a retrospective chart review of 10 patients with complete orthodontic records and greater than 1 year of follow-up was performed. Posteroanterior cephalograms were assessed by modified Grummons analysis to determine mandibular offset (deviation of the chin point from the skeletal midline) and occlusal cant. These measurements were performed at 3 time points (T1: preoperative, T2: immediate postoperative, T3: follow-up) to elucidate the surgical movement (T2–T1), the postoperative relapse (T3–T2), and the net gain movement (T3–T1). Maxillary movements were quantified, and the occlusal cant was expressed as a ratio between vertical heights of the maxilla at the first molar on each side. One sample t test demonstrated statistically significant surgical movement and net gain. Relapse was statistically insignificant. Repeated-measures analysis of variance demonstrated similar results for chin point position relative to the putative midline. Our results suggest that a combined orthodontic/orthognathic approach at skeletal maturity delivers improved occlusal outcomes in the long term as assessed by chin point deviation and occlusal cant, but secondary surgery rates are higher than those for orthognathic surgery in other patient groups. We advocate limiting surgery to skeletal maturity whenever possible to achieve stable long-term results while limiting morbidity and number of procedures.

A Novel Quantitative Method for Evaluating Surgical Outcomes in Craniosynostosis: Pilot Analysis for Metopic Synostosis

Objective assessment of head shape has been an elusive goal in the management of craniosynostosis patients. Clinical judgment, craniometric indices, and computed tomography scans are the primary means through which a surgeon assesses this patient population. The purpose of this study was to examine and discuss the utility of the STARscanner for evaluation of surgical outcomes in metopic synostosis patients. A retrospective chart review of patients with metopic synostosis who underwent fronto-orbital advancement with pre- and postoperative STARscanner imaging at Texas Childrens Hospital was performed. Two patients were identified and evaluation and discussion of the data produced by the STARscanner was undertaken. A novel symmetry index created by the authors, called the anterior–posterior volume ratio (APVR), was discussed for use in metopic synostosis patients. The postoperative growth metrics demonstrated an interval increase compared with the preoperative data. The anterior symmetry ratio, posterior symmetry ratio, overall symmetry ratio, cranial vault volumes, cranial vault asymmetry index, and cephalic ratio were not found to be useful in evaluating resolution of dysmorphology after fronto-orbital advancement in metopic synostosis. The APVR does not characterize dysmorphology, but may help show degree of expansion of the anterior cranial vault after fronto-orbital advancement. The STARscanner imaging device does not appear to have significant utility in characterizing head shape for surgical outcomes assessment in metopic synostosis. The minor utility of this device may be that it is a safe and fast way to derive growth parameters for both short-term and long-term follow-up of cranial vault remodeling.

Management of Pediatric Mandible Fractures

When determining the optimal treatment strategy for a pediatric mandible fracture, planning must factor in the patients age, anatomy, stage of dental development, fracture site, and ability to cooperate with the proposed treatment plan. Careful consideration must be given to the possibility of long-term growth disturbance with various fracture locations and types of treatment. This article reviews the current principles of the management of pediatric mandibular fractures.

Secondary Lip and Palate Surgery

To properly treat a patient with a secondary cleft lip or palate deformity, one must make an accurate diagnosis of the underlying problem. Recognition of specific recurring patterns and common deformities will help facilitate the surgical planning process and assist the surgeon during future procedures. Through a combination of accurate analysis, clinical patience, and technical precision, successful correction of secondary cleft lip and palate deformities can be delivered.

Cranial Fasciitis: A Systematic Review and Diagnostic Approach to a Pediatric Scalp Mass.

AbstractCranial fasciitis is an uncommon, benign fibroproliferative condition of the scalp or skull that arises in children. Clinically, it manifests as a firm, nontender, subcutaneous, enlarging mass. The purpose of our study was to review the literature on cranial fasciitis to create a diagnostic algorithm using the latest patient at our institution as an example. The authors conducted a systematic review examining all published cases of cranial fasciitis in English literature. The authors then created a diagnostic algorithm to help distinguish cranial fasciitis from other similarly presenting cranial masses. To demonstrate this algorithm, the authors detailed the latest patient with cranial fasciitis at our institution. The authors extracted data from 53 published reports documenting 72 patients of cranial fasciitis. Our patient presented similarly to what was reported in the literature. A 7-week-old boy presented with 2 small parietal scalp masses that were noted shortly after birth. After noncontrast computed tomography imaging, the enlarging masses were resected and found to have eroded the outer cranial vault cortex. Histological analysis revealed cranial fasciitis. The differential diagnosis for an enlarging scalp mass in an infant or child is broad. Cranial fasciitis cannot be diagnosed based on clinical presentation alone. Imaging is usually employed to further characterize lesions after initial examination but histopathological analysis is essential for diagnosis. The locally invasive nature of cranial fasciitis makes it difficult to distinguish from malignant conditions such as sarcomas. However, if the diagnosis of cranial fasciitis is considered early, patients can achieve prompt clinical resolution following simple resection.

Orthognathic Surgery: General Considerations

ORTHOGNATHIC SURGERY IS A UNIQUE ENDEAVOR IN FACIAL SURGERY a patients appearance and occlusal function can be improved significantly, impacting the patients sense of self and well-being. Successful outcomes in modern orthognathic surgery rely on close collaboration between the surgeon and the orthodontist across all stages of treatment, from preoperative planning to finalization of occlusion. Virtual computer planning promotes a more accurate analysis of dentofacial deformity and preoperative planning. It is also an invaluable aid in providing comprehensive patient education. In this article, the author describes the general surgical principles that underlie orthognathic surgery, highlighting the sequence of treatment, preoperative analysis of dentofacial deformity, surgical execution of the treatment plan, and possible complications.

Custom CAD/CAM implants for complex craniofacial reconstruction in children: Our experience based on 136 cases✰

BACKGROUND CAD-CAM patient-specific implants offer cerebral protection and improved facial balance without the disadvantages of autologous bone grafting such as donor site morbidity and unpredictable resorption. Several alloplastic materials are available, but titanium, polymethylmethacrylate (PMMA), and polyetheretherketone (PEEK) are the current popular choices. We reviewed our experience of applying different alloplastic CAD-CAM materials in the reconstruction of complex pediatric craniofacial deformities. METHODS A retrospective review was performed of all pediatric patients who underwent a complex inlay or onlay implant craniofacial reconstruction using CAD-CAM PEEK, PMMA, or titanium implants at a single institution. Demographics, cost, operative time, complications, and outcomes were assessed. RESULTS Between 2003 and 2014, 136 patients (69 male; 67 female; mean age 11.5 years (3-22 years); mean follow-up 30 months) had custom patient-specific craniofacial reconstruction with PEEK (n = 72), PMMA (n = 42), and titanium (n = 22) implants (inlay = 93; onlay = 43). Indications included congenital anomalies (26.5%), decompressive craniectomies (25.0%), craniofacial syndromes (25.7%), tumor defects (14.0%), and post-trauma (6.6%). Implant cost varied significantly for PEEK (