Walter M. Sweeney

Regulation of osteogenesis and survival within bone grafts to the calvaria: The effect of the dura versus the pericranium

Background: The present study evaluates the isolated role of dura and pericranium in the survival of fresh (osteoblasts viable) and frozen (osteoblasts nonviable) bone grafts. Methods: Bilateral craniectomies were performed in 48 mature rabbits. On one side, bone was replaced immediately; on the contralateral side, it was flash-frozen before replacement. Animals were randomized into four groups by placement of Silastic barriers adjacent to bone grafts, as follows: (1) control (no barriers); (2) dural barrier; (3) pericranial barrier; and (4) double (dural and pericranial) barriers. Fluorescein labels were injected at specified intervals, with animals euthanized after 1 or 10 weeks. Results: After 1 week, fresh grafts without dural barriers demonstrated greater fluorescein labeling on the dural than on the pericranial surface (p < 0.05); in contrast, fresh grafts without pericranial barriers had no statistical difference in fluorescein labeling between pericranial and dural surfaces. After 10 weeks, the new bone area was greater in fresh than in frozen grafts (p < 0.05). Total new bone area and dural-side new bone were greater in grafts without dural barriers (p < 0.001); this was not seen in grafts without pericranial barriers. Pericranial new bone was greatest in fresh grafts without a pericranial barrier (p < 0.001); this was not seen in frozen grafts. Conclusions: The dura and pericranium each contributed to osteogenesis, although dural contact was more effective. Maintenance of dural contact enhanced osteogenesis through the entire graft, whereas pericranial contact enhanced osteogenesis only on the pericranial surface of fresh grafts. These data suggest dura is largely responsible for cranial graft survival.

The Academic Scholar Award of the American Association of Plastic Surgeons: The First 20 Years

Background: This study evaluated the 20-year history of the American Association of Plastic Surgeons Academic Scholar Award from 1992 through 2012, to assess the program’s value and justify future investment. Methods: The curricula vitae of 18 Academic Scholars who completed their award by 2012 were analyzed. Data were compiled into 5-year blocks and reviewed. Results: Award recipients has 589 grants, an average of 33 per recipient. Sixty-nine grants were active, and the recipient was the principal investigator in 61 of these grants. Active funding is

Distinguishing anatomic features of pediatric facial trauma

68 million. Recipients average 3.7 active grants per person, with a value of

Anatomic survey of arachnoid foveolae and the clinical correlation to cranial bone grafting

3.8 million per grant. The average number of grants peaks at 5 to 10 years after award completion and then declines slightly to 42 at 10 to 15 years. During this time, total grant money increased from

Long-Term Follow-up of a Tessier Number 5 Facial Cleft.

956,667 to

Double-opposing Z-plasty for secondary surgical management of velopharyngeal insufficiency following primary furlow palatoplasty

8.1 million, suggesting that senior surgeons produce more money with fewer grants. Recipients produced 2378 peer-reviewed articles, and productivity was the highest 5 to 10 years after award completion. Three hundred forty-one individuals were mentored, and each recipient mentored an average of 18 individuals. Forty-two mentees entered academics, and 32 generated extramural funding. Scholars increased mentorship activity, as demonstrated by (1) increased grants as any role, (2) increased grant funding as any role, (3) increased median number of senior author publications, and (4) mentorship activities and accomplishments of mentees. Conclusions: The Academic Scholar program met its goals based on (1) Scholars’ careers, (2) increased mentorship, and (3) cost-benefit ratio of the American Association of Plastic Surgeons investment. Every

New Insights into the Anatomy of the Midface Musculature and its Implications on the Nasolabial Fold (Discussion).

1 invested produces

Rhinoplasty Video Library, Volume II: Structural Grafting for Definitive Management of the Unilateral Cleft Lip Nasal Deformity.

70, with a return that exceeds 1000 percent.

Modified Lipoabdominoplasty Without Surgical Drains

T rauma is the leading cause of morbidity and mortality in children, and injury remains the most common cause of death in children 1 year and older. This results in the permanent disabilities of 100,000 children and approximately 15,000 deaths at a cost of

Calcium phosphate cements in skull reconstruction: A meta-analysis

15,000 million annually.1 Although severe pediatric craniofacial injury is less common than in the adult population, head trauma remains the most common cause of death related to injury in the pediatric population. Using the National Trauma Data Bank from 2001 to 2005, Imahara et al reported an epidemiologic survey of pediatric trauma patients. In their report, the most common facial fractures were the mandible (32.7%), nasal (30.2%), and maxillary/zygoma (28.6%). The most common mechanisms of injury were motor vehicle collision (55.1%), violence (11.8%), and falls (8.6%). Although basic management principles used to address craniofacial trauma are fairly consistent across age demographics, proper management of the pediatric population requires an intimate understanding of the anatomic variations in children as compared with adults. In this article, we will attempt to provide the reader with an overview of pediatric facial anatomy while highlighting the affect of anatomic and developmental differences on pediatric craniofacial trauma. The immature craniofacial structures and differences in skeletal physiology significantly influence the incidence, location, and severity of facial trauma observed in children. While the pediatric cranium starts to develop, there is protrusion of the frontal bone accompanied by retrusion of midface structures; this drastically alters the proportions of the skull before puberty (Fig. 1). This causes the frontal bone to generate a greater risk of fracture during blunt force trauma, thus ‘‘protecting’’ the face. The significant growth of the craniofacial skeleton is underscored by the dramatic change in the skull-to-face ratio that is 8:1 at birth and 2.5:1 in adulthood. Furthermore, the cranium quadruples in size from birth to adulthood, whereas the face undergoes a 12-fold increase (Fig. 2). In addition to the variations in craniofacial proportions, the pediatric facial skeleton has increased cancellous bone and flexible suture lines that confer greater skeletal elasticity and flexibility. In contrast to adults, children also possess a thick layer of adipose over much of the pediatric facial skeleton as well as fat pads that surround the upper and lower jaw. The culminating effect is a stable skeletal structure capable of enduring considerable force before fracturing. This is also the reason children have a high incidence of greenstick fractures after facial trauma. The key factors that have a substantial impact on pediatric facial development and stability include the pneumatization of the sinuses and phases of dentition. These events have the single greatest effects on the evolving fracture patterns and anatomic locations observed with increasing age. With regard to dentition, 3 phases have been described: (a) a deciduous phase, around the age of 2 years, (b) a mixed phase, from 6 to 12 years, and (c) a permanent or definitive phase, around 13 years. Tooth buds present during the first 2 phases of incomplete dentition increase the stability of the mandible and maxilla, decreasing the likelihood of fracture after impact. The eruption of permanent dentition will also increase facial vertical height and enhance the anterior projection of the tooth bearing structures: the maxilla and mandible. Pneumatization of the sinuses is the second developmental milestone that alters the susceptibility of the pediatric cranium to fractures. Pneumatization of the paranasal sinuses begins in the ethmoid sinus and continues sequentially in the maxillary sinuses, the sphenoid sinuses, and finally, the frontal sinuses (Fig. 3). The maxillary and frontal sinuses play an important role in pediatric facial fracture patterns, with a positive correlation existing between the frequency of midfacial fractures and the stage of development and pneumatization of the paranasal sinuses. The lack of pneumatization is associated with increased stability; however, with greater pneumatization, the sinuses may absorb more of the impact and provide a cushioning effect critical for protection of delicate skull base structures.