Faculty Bibliography

Mandibular distraction osteogenesis is an established technique used to treat infants with Pierre Robin sequence associated with severe airway obstruction. The authors present a 7-year retrospective review of all patients with Pierre Robin sequence treated with mandibular distraction osteogenesis. Recorded variables included improvements in apnea/hypopnea index and postintervention tracheostomy. Multiple preoperative variables were assessed for association with successful mandibular distraction osteogenesis or tracheostomy. Fifty patients were identified for this study. Four patients (8 percent) required tracheostomy after distraction. A Fisher's exact test demonstrated no statistical association of tracheostomy with prematurity, low birth weight, preoperative intubation, late intervention, genetic syndromes, cardiac abnormalities, pulmonary abnormalities, or gastrostomy tube. The absence of a cleft palate, gastroesophageal reflux disease, and need for Nissen fundoplication were associated with failure of distraction. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

BACKGROUND: The authors present a prospective, randomized, blinded trial comparing the educational efficacy of digital animation versus a textbook in teaching the Ivy loop technique to novice learners. METHODS: Medical student volunteers (n = 32) were anonymously videotaped as they fastened dental wire to the teeth of a skull model (preintervention analysis) and then were randomly assigned to one of two study groups. The animation and text groups (n = 16 each) were shown either a digital animation or textbook demonstrating the Ivy loop surgical technique. Volunteers were then videotaped as they performed the technique (postintervention analysis). Volunteers were then shown the educational material provided to the other study group and given a validated educational survey to compare the educational value of both materials. Preintervention and postintervention video recordings were graded using a validated surgical competency scale. Surgical performance grades, time to task completion, and educational survey scores were compared. RESULTS: Preintervention analysis performance scores did not significantly differ between the animation and text groups (10.7 [2.8] versus 11.1 [3.9]; p = 0.74), but postintervention analysis demonstrated significantly higher performance scores in the animation group (18.8 [2.9] versus 13.0 [3.5]; p < 0.001). Time to task completion was similar. The educational survey demonstrated significantly higher scores in the animation group. CONCLUSIONS: A prospective, randomized, blinded study comparing the educational efficacy of a surgical textbook to digital animation demonstrates that, in novice learners, digital animation is a more effective tool for learning the Ivy loop technique. Test takers found digital animation to be the superior educational medium.

BACKGROUND: Frontal sinus cranialization is commonly indicated for posterior table fractures with significant comminution, displacement, or cerebrospinal fluid leaks. This study assessed the clinical outcomes of conservative management. METHODS: A 10-year retrospective review of all frontal sinus fractures treated at a level 1 trauma center was performed using medical records and radiographic images. RESULTS: A total of 875 patients with frontal sinus fractures were identified, and 68 had posterior table involvement. Nine died within the first 48 hours from other injuries. The remaining 59 patients constituted the study population. Average follow-up approached 1 year (342 days). The more common mechanisms of injury were blunt interpersonal violence (29 percent) and motor vehicle accidents (27 percent). Concurrent central nervous system injury was common (73 percent), and the average Glasgow Coma Scale score was 12.7. Posterior wall fracture pattern was nondisplaced and noncomminuted in 33 patients (54 percent) and comminuted and/or displaced in 27 (46 percent). Cerebrospinal fluid leak was recorded in 11 patients (19 percent). Conservative management was the more common strategy (78 percent), followed by open reduction and internal fixation with sinus preservation (12 percent), obliteration (8 percent), and cranialization (2 percent). Of the 27 patients with comminuted and/or displaced fractures, 16 (59 percent) underwent conservative management, and 11 (41 percent) underwent surgical management, but only one patient (2 percent) underwent cranialization. There was no incidence of intracranial infection, except for one patient who died from encephalitis secondary to a gunshot wound to the head. CONCLUSION: The vast majority of frontal sinus fractures involving the posterior table, including those with comminution, displacement, or cerebrospinal fluid leaks, can be safely managed without cranialization. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

We review the literature on medial orbital wall fractures and perform a meta-analysis on outcomes with the transcaruncular approach. The reported incidence for this injury ranges widely, although diagnosis can be made effectively with clinical examination and computed tomography. Clinical sequelae can include rectus entrapment or herniation, enophthalmos, and diplopia. Local injuries occurring in high concordance include concomitant fractures of the orbital floor and nasal fractures, although anterior cranial fossa extension, ocular trauma, other craniofacial injuries, and polytrauma must be ruled out. Indications for operative intervention include large defects, early or persistent enophthalmos particularly if causing diplopia, and rectus muscle entrapment.Various surgical approaches to the medial orbit have been described; however, the transcaruncular approach offers direct, reliable access without creating a cutaneous scar on the central face. A meta-analysis was performed on all studies reporting outcomes of the transcaruncular approach. A total of 228 cases were pooled, finding a favorable overall complication rate of 2.6%. Half of these complications required surgical correction and half resolved nonoperatively.Medial orbital wall fractures are an increasingly appreciated injury requiring clinical and radiologic assessments. When indicated, reconstruction of the medial orbital wall can be safely and effectively performed with the transcaruncular approach. Additional prospective outcomes studies are required to elucidate (1) the incidence of medial orbital wall fractures, (2) indications for operative versus nonoperative management, and (3) outcomes analysis of the transcaruncular approach compared with other approaches.

BACKGROUND: Syndromic craniosynostosis is associated with a high incidence of elevated intracranial pressure. The most common treatment paradigm is to perform anterior cranial vault reconstruction in infancy followed later by possible expansion of the posterior cranial vault and midface advancement. Recently, however, posterior cranial vault expansion has been advocated as an initial step in treatment. We sought to quantify volumetric changes with anterior versus posterior cranial vault surgery in these patients. MATERIALS AND METHODS: We reviewed patients with syndromic brachycephalic craniosynostosis treated in our unit from 2002 to 2009 with existing preoperative fine-cut computed tomographic scans. Using computer software (Analyze; Mayo Clinic, Rochester, MN) and computed tomographic data, the senior author simulated both anterior and posterior cranial vault expansions. Expansion was simulated with a series of translational advancements of the separated segments. Volumetric data were compared for each simulated procedure. RESULTS: Thirteen patients underwent simulated cranial vault reconstructions. At 2, 10, and 20 mm of anterior advancement, the mean increase in intracranial volume was 1.8%, 8.8%, and 17.7%, respectively, whereas posterior advancements achieved 2.4%, 11.9%, and 23.9%, respectively. On average, posterior cranial vault reconstruction created 35% more relative expansion than anterior expansion at equivalent degrees of advancement (P < 0.001). In all simulations, posterior cranial vault reconstruction created greater intracranial volume changes than anterior reconstructions. CONCLUSIONS: This simulation demonstrates that, in syndromic brachycephalic craniosynostosis, posterior cranial vault advancement achieves approximately 35% greater intracranial volume expansion compared with equivalent degrees of anterior cranial vault advancement. This may help guide decisions in treatment sequencing of patients with syndromic craniosynostosis.

BioDigital Systems, LLC in collaboration with New York University Langone Medical Center Department of Reconstructive Plastic Surgery has created a complex, real-time, step-based simulation platform for plastic surgery education. These simulators combine live surgical footage, interactive 3D visualization, text labels, and voiceover as well as a high-yield, expert-approved testing mode to create a comprehensive virtual educational environment for the plastic surgery resident or physician.

BACKGROUND: Flexor tendon injuries are common problems faced by hand surgeons. To minimise the surgical trauma associated with localisation and retrieval of the proximal tendon end, we investigated the use of surgeon-performed ultrasound in the evaluation of injured flexor tendons in a cadaver model. Our goal was to use surgeon-performed ultrasound: (1) to correctly diagnose flexor tendon injuries and (2) to correctly localise the proximal tendon ends within 1cm. METHODS: Flexor tendon injuries with varying degrees of retraction were randomly created in individual digits of cadaver upper extremities, with a number of tendons left uninjured. A surgeon, blinded to the injury status of each digit, imaged each tendon by ultrasound. Predicted injury status of each tendon and localisation of the proximal stump was recorded. A total of 81 tendons were studied. FINDINGS: Correct diagnosis of flexor tendon injury was made in 78 of 81 tendons (96.2% success). Correct localisation of the proximal tendon stump was made in 39 of 50 lacerated tendons (78% success). Small finger injuries were most difficult to assess (66.7% success). With the small finger excluded from our analysis, the localisation success rate increased to 86.8%. The average time taken to image each digit was just under 2.5min. CONCLUSIONS: Surgeon-performed ultrasound evaluation of the hand is a reliable means to diagnose flexor tendon injuries and to accurately localise the proximal tendon ends. This imaging modality may limit the need for extensive surgical exploration during flexor tendon repair. We do not recommend using this technique to image flexor tendon injuries of the small finger at this time

BACKGROUND:: Three-dimensional digital animation can enable surgeons to create anatomically accurate, virtual models of normal and pathologic human anatomy. From these models, surgical procedures can be digitally performed, recorded, and distributed as a teaching tool or as a virtual surgical atlas. The idea of a virtual surgical atlas has recently become a part of contemporary surgical teaching. In the field of craniofacial surgery, no such educational tool exists. Presented is the first part of the creation of a virtual atlas of craniofacial surgical procedures: the three-dimensional digital modeling of pathologic deformities commonly treated by craniofacial surgeons. METHODS:: Three-dimensional craniofacial models were constructed using Maya 8.5. A skeletally 'normal' craniofacial skeleton was first produced from a preexisting digital skull using Bolton tracings as a reference. The remaining soft-tissue elements were then added to create an anatomically complete three-dimensional face. The 'normal' model was then deformed in Maya to produce specific craniofacial deformities using computed tomographic scans, cephalograms, and photographs as a reference. One of the craniofacial deformity models was created directly from computed tomographic data. RESULTS:: One model of the normal face and eight pathologic models of craniofacial deformities were created: microgenia, micrognathia, prognathia, temporomandibular joint ankylosis, maxillary hypoplasia, Crouzon syndrome with and without the need for cranial vault expansion, and bicoronal craniosynostosis. CONCLUSIONS:: For the first time, anatomically accurate three-dimensional digital models of craniofacial deformities have been created. The models are the first step in the creation of a virtual surgical atlas of craniofacial procedures

BACKGROUND:: Craniofacial surgery can be challenging to teach and learn. To augment the intraoperative learning experience for surgical trainees and to provide a resource for practicing craniofacial surgeons to review uncommonly performed procedures before entering the operating room, a series of three-dimensional animations were created encompassing the most commonly performed craniofacial procedures. METHODS:: Previously created three-dimensional craniofacial digital models were used to create digital animations of craniofacial surgical procedures using Maya 8.5. Digital models were altered systematically within Maya to recreate the ordered steps of each craniofacial procedure. Surgical tools were imported into Maya for use in the animations using computer-aided manufacturing files obtained directly from the manufacturer. RESULTS:: Nine craniofacial procedures were animated: genioplasty, bilateral sagittal split osteotomy, intraoral vertical ramus osteotomy, Le Fort I osteotomy, unifocal mandibular distraction, mandibular transport distraction, fronto-orbital advancement with cranial vault remodeling, Le Fort III advancement/distraction, and monobloc advancement/distraction. All major surgical steps are demonstrated, including exposure, execution of the osteotomy, displacement of the bone composite, and the predicted morphologic changes to the craniofacial contour. Throughout the surgical animation, the view of the surgeon in the operating room is incorporated to reproduce the vantage of the surgeon, and the overlying tissue is rendered transparent to illustrate critical underlying anatomical relationships. CONCLUSIONS:: The first virtual surgical atlas of craniofacial procedures is presented. These animations should serve as a resource for trainees and practicing surgeons in preparation for craniofacial surgical procedures