Faculty Bibliography

This study aimed to determine the effect of a bioactive ceramic coating on titanium in the nanothickness range on human osteogenic cells, peripheral blood mononuclear cells (PBMC) and on osteogenic cells co-cultured with PBMC without exogenous stimuli. Cell viability, proliferation, adhesion, cytokine release (IL1beta, TGFbeta1, IL10 and IL17) and intracellular stain for osteopontin and alkaline phosphatase were assessed. Morphologic evaluation showed smaller and less spread cell aspects in co-culture relative to osteogenic cell culture. Cell viability, proliferation and adhesion kinetics were differently influenced by surface texture/chemistry in culture versus co-culture. Cytokine release was also influenced by the interaction between mononuclear and osteogenic cells (mediators released by mononuclear cells acted on osteogenic cells and vice versa). In general, 'multi-cell type' interactions played a more remarkable role than the surface roughness or chemistry utilized on the in vitro cellular events related to initial stages of bone formation.

Few studies have evaluated the effects of titanium (Ti) surface modifications on polymorphonuclear neutrophils (PMNs). Human PMNs' viability and release of key mediators-such as IL1beta, IL6, TNFalpha, IL12, IL10, IL4, TGFbeta1, IL8, IP-10, and Mig-were evaluated on three different Ti surface treatments: (1) machined Ti; (2) alumina-blasted and acid-etched Ti (AB/AE); and (3) calcium phosphate coating of 300-500 nm by ion beam onto the AB/AE Ti surface (CaP). A polystyrene surface was used as a negative control. The PMNs were purified from whole human blood and cultured for 6 h. Cell viability was determined by flow cytometry, and the supernatant was evaluated to determine the levels of cytokines and chemokines. Results showed that the percentage of viable cells was significantly lower on the CaP surface compared to the control (p < 0.05) relative to the other groups. No differences in the levels of IL8, MIG, and IP10 were detected between groups. Significantly higher levels of IL1beta (p = 0.046) and TNFalpha (p = 0.016) were detected for the CaP surfaces compared to AB/AE surface only. The levels of IL4, IL10, and TGFbeta1 secreted from the PMNs in the CaP group were significantly lower than in the control and machined groups (p < 0.05) that were statistically comparable to AB/AE. Overall, the addition of a thin CaP coating to the AB/AE Ti surface influenced the secretion profile of pro-inflammatory cytokines due to the higher release of pro-inflammatory cytokines (IL1beta and TNFalpha) on these surfaces.

BACKGROUND: Treatment of facial fractures in the setting of open-globe injuries poses a management dilemma because of the often disparate treatment priorities of multidisciplinary trauma teams and the lack of prognostic data regarding visual outcomes. METHODS: Patients in the University of Maryland Shock Trauma Registry sustaining facial fractures with concomitant open-globe injuries from January of 1998 to August of 2010 were identified. Odds ratios were calculated to identify demographic and clinical variables associated with blindness, and multivariate regression analysis was performed. RESULTS: A total of 99 patients were identified with 105 open-globe injuries. Seventy-nine percent of injuries were blinding, whereas 4.8 percent of globes achieved a final visual acuity greater than or equal to 20/400. Blindness was associated with penetrating injury, increasing number of facial fractures, zygomaticomaxillary complex fracture, admission Glasgow Coma Scale score less than or equal to 8, and globe injury spanning all three eye zones. Fracture repair was performed more frequently (62.5 percent) and more quickly (average time to fracture repair, 4.5 days) in cases of primary globe enucleation/evisceration when compared with complete (21.2 percent; 8 days; p=0.35) or incomplete (42.9 percent; 11 days; p=0.058) primary globe repair. CONCLUSIONS: Penetrating injury mechanism and zone of eye injury appear to be better indicators of visual prognosis than facial fracture patterns. Given the high rates of blindness, secondary enucleation, and delay of fracture repair in patients that were not primarily enucleated, the authors recommend that orbital fracture repair not be delayed in the hopes of eventual visual recovery in cases of high-velocity projectile trauma. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

BACKGROUND: Despite the putative advantages conferred by closed-suction drains (CSDs), the widespread utilization of post-operative drains has been questioned due to concerns regarding both efficacy and safety, particularly with respect to the risk of surgical site infection (SSI). Although discipline-specific reports exist delineating risk factors associated with SSI as they relate to the presence of CSDs, there are no broad summary studies to examine this issue in depth. METHODS: The pertinent medical literature exploring the relationship between CSDs and SSI across multiple surgical disciplines was reviewed. RESULTS: Across most surgical disciplines, studies to evaluate the risk of SSI associated with routine post-operative CSD have yielded conflicting results. A few studies do suggest an increased risk of SSI associated with drain placement, but are usually associated with open drainage and not the use of CSDs. No studies whatsoever attribute a decrease in the incidence of SSI (including organ/space SSI) to drain placement. CONCLUSIONS: Until additional, rigorous randomized trials are available to address the issue definitively, we recommend judicious use and prompt, timely removal of CSDs. Given that the evidence is scant and weak to suggest that CSD use is associated with increased risk of SSI, there is no justification for the prolongation of antibiotic prophylaxis to "cover" an indwelling drain.

BACKGROUND: Chronic rejection of vascularized composite allografts (VCA) is an emerging phenomenon that may decrease long-term allograft survival and impair allograft function. Although intimal hyperplasia has been reported in human hand transplants, chronic changes in VCAs remain poorly described. METHODS: We developed a nonhuman primate model of face transplantation to evaluate the effect of various immunosuppressive regimens on allograft survival that we have previously reported. Nineteen grafts were successfully transplanted and serially biopsied to assess for rejection. Five VCA grafts with long-term survival (>200 days) were weaned off immunosuppression. We performed additional histologic and immunohistochemical studies on previously collected samples. RESULTS: All five grafts developed features consistent with chronic rejection, including neointimal proliferation, transplant vasculopathy, vessel wall fibrosis, progressive luminal occlusion, and tertiary lymphoid follicles. Review of 186 serial allograft skin and subcutaneous tissue biopsies revealed that tertiary follicles and vascular changes developed in the absence of acute skin rejection. No relationship was found between alloantibody production and these changes. CONCLUSIONS: Recognition of these characteristics of VCA chronic rejection is important for diagnosis in clinical hand and face transplantation. Studies directed towards minimizing VCA chronic rejection responses may be required to improve long-term outcomes.

BACKGROUND: Access to the frontal sinus remains a challenging problem for the craniofacial surgeon. A wide array of techniques including minimally invasive endoscopic approaches have been described. Here we present our technique using medical modeling to gain fast and safe access for multiple indications. METHODS: Computer-aided surgery involves several distinct phases: planning, modeling, surgery, and evaluation. Computer-aided, precise cutting guides are designed preoperatively and allowed to perfectly outline and then cut the anterior table of the frontal sinus at its junction to the surrounding frontal bone. The outcomes are evaluated by postoperative three-dimensional computed tomography scan. RESULTS: Eight patients sustaining frontal sinus fractures were treated with the aid of medical modeling. Three patients (37.5%) had isolated anterior table fractures, and 4 (50%) had combined anterior and posterior table fractures, whereas 1 patient (12.5%) sustained isolated posterior table fractures. Operative times were significantly shorter using the cutting guides, and fracture reduction was more precise. There was no statistically significant difference in complication rates or overall patient satisfaction. CONCLUSIONS: The surgical approach to the frontal sinus can be made more efficient, safe, and precise when using computer-aided medical modeling to create customized cutting guides.

BACKGROUND: : Nipple-sparing mastectomy has gained popularity, but the question remains of whether it can be offered safely to women with a history of reduction mammaplasty or mastopexy. The authors present their experience with nipple-sparing mastectomy in this patient population. METHODS: : Patients at the authors' institution who had reduction mammaplasty or mastopexy before nipple-sparing mastectomy were identified. Outcomes measured include nipple-areola complex viability, mastectomy flap necrosis, infection, presence of cancer in the nipple-areola complex, and breast cancer recurrence. RESULTS: : The records of the nipple-sparing mastectomy patients at the authors' institution from 2006 through 2012 were reviewed. The authors identified 13 breasts in eight patients that had nipple-sparing mastectomy following reduction mammaplasty or mastopexy. Within this subset of patients, the mean age was 46.6 years and the mean body mass index was 25.1. Nine of 13 breasts had therapeutic resections, whereas the remaining four were for prophylactic indications. Average time elapsed between reduction mammaplasty or mastopexy and nipple-sparing mastectomy was 51.8 months (range, 33 days to 11 years). In all cases, prior reduction mammaplasty/mastopexy incisions were used for nipple-sparing mastectomy. Ten breasts underwent reconstruction immediately with tissue expanders, one with a latissimus dorsi flap with immediate implant and two with immediate abdominally based free flaps. Complications included one hematoma requiring evacuation and one displaced implant requiring revision. There were no positive subareolar biopsy results, and the nipple viability was 100 percent. Mean follow-up time was 10.5 months. CONCLUSIONS: : The authors' experience demonstrates that nipple-sparing mastectomy can be offered to patients with a history of reduction mammaplasty or mastopexy with reconstructive outcomes comparable to those of nipple-sparing mastectomy alone. CLINICAL QUESTION/LEVEL OF EVIDENCE: : Therapeutic, IV.

Bone repair and regeneration are dynamic processes that involve a complex interplay between the substrate, local and systemic cells, and the milieu. Although each constituent plays an integral role in faithfully recreating the skeleton, investigators have long focused their efforts on scaffold materials and design, cytokine and hormone administration, and cell-based therapies. Only recently have the intangible aspects of the milieu received their due attention. In this review, we highlight the important influence of environmental factors on bone tissue engineering. (c) 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013.

Strabismus is common in craniosynostosis, with rates from 39% to 90.9% in Crouzon, Apert, Pfeiffer, and Saethre-Chotzen syndromes. This article reviews the epidemiology of strabismus in these disorders and discusses competing theories of the mechanism, including absent muscles, excyclorotation of muscles, and instability of muscle pulleys. The authors then review options for surgical treatment of the often complex ocular misalignment in these disorders.