Plastic Surgery and Acellular Dermal Matrix: Highlighting Trends from 1999 to 2013.

The last decade has ushered in a rapidly expanding global discussion regarding acellular dermal matrix (ADM) applications, economic analyses, technical considerations, benefits, and risks, with recent emphasis on ADM use in breast surgery. This study aims to evaluate global trends in ADM research using bibliometric analysis. The top nine Plastic Surgery journals were determined by impact factor (IF). Each issue of the nine journals between 1999 and 2013 was accessed to compile a database of articles discussing ADM. Publications were further classified by IF, authors' geographic location, study design, and level of evidence (LOE, I-V). Productivity index and productivity share were calculated for each region. In total, 256 ADM articles were accessed. The annual global publication volume increased significantly by 4.2 (0.87) articles per year (p<0.001), with a mean productivity index of 36.3 (59.0). The mean impact factor of the nine journals increased significantly from 0.61 (0.11) to 2.47 (0.99) from 1993 to 2013 (p<0.001). Despite this increase in the global ADM literature, the majority of research was of weaker LOE (level I: 2.29% and level II: 9.17%). USA contributed the most research (87%), followed by Asia (4.76%) and Western Europe (4.71%). USA contributed the greatest volume of research. Regarding clinical application of ADM, the majority of publications focused on ADM use in breast surgery, specifically breast reconstruction (154 articles, 60.2%). The majority of research was of lower LOE; thus, efforts should be made to strengthen the body of literature, particularly with regard to cost analysis.

Quantifying Optimal Columellar Strut Dimensions for Nasal Tip Stabilization After Rhinoplasty via Finite Element Analysis.

IMPORTANCE: The contribution of columellar strut grafts (CSGs) to nasal tip support has not been determined via structural mechanics. Optimal graft dimensions have yet to be objectively determined. OBJECTIVES: To use a finite element model (FEM) of the human nose to (1) determine the effect of the CSG on nasal tip support and (2) identify how suture placement contributes to tip support. DESIGN, SETTING, AND PARTICIPANTS: A multiple-component FEM of the human nose consisting of bone, skin/soft tissue, and cartilage was rendered from a computed tomographic scan. Then, CSGs of varying sizes were created, ranging from 15 × 4 × 1 mm to 25 × 8 × 1 mm, and placed in the model between the medial crura. Two FEMs were constructed for each strut size: (1) CSGs that were physically attached to the nasal spine, medial crura, and caudal septum and (2) CSGs that were not in direct contact with these structures and free to move within the soft tissue. A control model was also constructed wherein no graft was placed. MAIN OUTCOMES AND MEASURES: Nasal tip support for each model was assessed, and the resultant distribution of von Mises stress, reaction force, and strain energy density with respect to the alar cartilages were calculated. RESULTS: Compared with the control, the reaction force increased with increasing strut volume, while the strain energy density (calculated over the alar cartilages) generally decreased with increasing CSG volume. Simulations with struts that had suture attachments along the entire length of the graft generated a larger reaction force than the models without any suture attachments. Models with anteriorly placed sutures generated reaction forces similar to that of the fully sutured model, whereas the models with posterior sutures showed reaction forces similar to the fully disconnected model. CONCLUSIONS AND RELEVANCE: Insertion of CSGs does effect the amount of force the nasal tip can withstand post rhinoplasty. Moreover, anteriorly placed sutures incur reaction forces similar to struts that are fully connected to the alar cartilage. Thus, our simulations are congruent with clinical practice in that stability increases with graft size and fixation, and that sutures should be placed along either the entire CSG or the anterior most portion for optimal support. LEVEL OF EVIDENCE: NA.

Modular Component Assembly Approach to Microtia Reconstruction.

BACKGROUND: Current methods of microtia reconstruction include carving an auricular framework from the costal synchondrosis. This requires considerable skill and may create a substantial defect at the donor site. OBJECTIVE: To present a modular component assembly (MCA) approach that minimizes the procedural difficulty with microtia repair and reduces the amount of cartilage to a single rib. DESIGN, SETTING, AND PARTICIPANTS: Ex vivo study and survey. A single porcine rib was sectioned into multiple slices using a cartilage guillotine, cut into components outlined by 3-dimensional printed templates, and assembled into an auricular scaffold. Electromechanical reshaping was used to bend cartilage slices for creation of the helical rim. Chondrocyte viability was confirmed using confocal imaging. Ten surgeons reviewed the scaffold constructed with the MCA approach to evaluate aesthetics, stability, and clinical feasibility. The study was conducted from June 5 to December 18, 2014. MAIN OUTCOMES AND MEASURES: The primary outcome was creation of a modular component assembly method that decreases the total amount of rib needed for scaffold construction, as well as overall scaffold acceptability. The surgeons provided their assessments through a Likert-scale survey, with responses ranging from 1 (disagree with the statement) to 5 (agree with the statement). Thus, a higher score represents that the surgeon agrees that the scaffold is structurally and aesthetically acceptable and feasible. RESULTS: An auricular framework with projection and curvature was fashioned from 1 rib. The 10 surgeons who participated in the survey indicated that the MCA scaffold would meet minimal aesthetic and anatomic acceptability. When embedded under a covering, the region of the helix and antihelix of the scaffold scored significantly higher on the assessment survey than that of an embedded alloplast implant (mean [SD], 4.6 [0.97] vs 3.5 [1.27]; P = .007). Otherwise, no significant difference was found between the embedded MCA and alloplast implants (4.42 [0.48] vs 3.87 [0.41]; P = .13). Cartilage prepared with electromechanical reshaping was viable. CONCLUSIONS AND RELEVANCE: This study demonstrates that 1 rib can be used to create an aesthetic and durable framework for microtia repair. Precise assembly and the ability to obtain thin, uniform slices of cartilage were essential. This cartilage-sparing MCA approach may be an alternative to classic techniques. LEVEL OF EVIDENCE: NA.

Breast Microsurgery in Plastic Surgery Literature: A 21-Year Analysis of Publication Trends.

Introduction Microsurgical reconstruction of the breast represents an area of continual evolution, as new autologous flaps are introduced and principles are refined. This progression can be demonstrated by bibliometric analysis of the scientific literature. Methods The top 10 plastic surgery journals were determined by impact factor (IF). Each issue of every journal from 1993 to 2013 was accessed directly, and all articles discussing microsurgery on the female breast were classified by authors' geographic location, study design, and level of evidence (LOE, I-V). The productivity index and productivity share of each geographic region was calculated based on number of articles published and IF. Results A total of 706 breast microsurgery articles were analyzed. There was a significant increase in microsurgical breast research (p < 0.01), with an average 33.6 ± 31.1 articles per year and a mean increase of 4.4 articles per year. Most research was of lower LOE, with level I constituting 0.14% and level II constituting 5.21% of all articles. United States contributed the most research with 336.4 articles, followed by Western Europe with 242.2. However, Western Europe experienced the greatest increase in productivity share, with + 0.50 ± 0.29 growth, while United States demonstrated the greatest decrease in productivity share with - 1.23 ± 0.31 growth. Among autologous flaps, transverse rectus abdominis muscle research had the greatest yearly publication volume until 2002, when overtaken by deep inferior epigastric perforator flap research. Conclusion Over the 21-year study period, the United States not only contributed the greatest volume of research on female breast microsurgery but also demonstrated the greatest decline in research productivity. Efforts should be made to increase the LOE in breast microsurgery research.

Synergistic interactions between cytokines and AVP at the blood-CSF barrier result in increased chemokine production and augmented influx of leukocytes after brain injury.

Several lines of evidence indicate that the blood-cerebrospinal fluid barrier (BCSFB), which primarily resides in the choroid plexus (CP), plays a significant pathophysiological role not only in neuroinflammatory diseases, such as multiple sclerosis, but also in traumatic brain injury (TBI). Here we investigated how arginine vasopressin (AVP) regulates function of the BCSFB in the context of post-traumatic neuroinflammation. It has previously been shown that AVP exacerbates various forms of brain injury, but the mechanisms underlying this AVP action are poorly understood. Type 1A AVP receptor is highly expressed on the CP epithelium and the CP synthesizes AVP. Using the controlled cortical impact model of TBI, we demonstrated decreased post-traumatic production of proinflammatory mediators by the CP and reduced influx of inflammatory cells across the BCSFB in AVP-deficient Brattleboro rats when compared with Long-Evans rats, a parental strain for Brattleboro rats. Arginine vasopressin was also found to play an important role in post-traumatic activation of c-Jun N-terminal kinase (JNK) in the CP. In the CP epithelial cell cultures, AVP augmented the tumor necrosis factor-α- and interleukin-1ß-dependent increase in synthesis of proinflammatory mediators, including neutrophil chemoattractants, an action largely dependent on the JNK signaling pathway. Under in vivo conditions, a selective JNK inhibitor decreased the post-traumatic production of neutrophil chemoattractants by the CP and reduced the influx of neutrophils across the BCSFB. These results provide evidence for the synergistic interactions between proinflammatory cytokines and AVP, a ligand for G protein-coupled receptors, and support a pathophysiological role of AVP in post-traumatic neuroinflammation.

Posttraumatic invasion of monocytes across the blood-cerebrospinal fluid barrier.

The invasion of inflammatory cells occurring after ischemic or traumatic brain injury (TBI) has a detrimental effect on neuronal survival and functional recovery after injury. We have recently demonstrated that not only the blood-brain barrier, but also the blood-cerebrospinal fluid (CSF) barrier (BCSFB), has a role in posttraumatic recruitment of neutrophils. Here, we show that TBI results in a rapid increase in synthesis and release into the CSF of a major chemoattractant for monocytes, CCL2, by the choroid plexus epithelium, a site of the BCSFB. Using an in vitro model of the BCSFB, we also show that CCL2 is released across the apical and basolateral membranes of the choroidal epithelium, a pattern of chemokine secretion that promotes leukocyte migration across epithelial barriers. Immunohistochemical and electron microscopic analyses of choroidal tissue provide evidence for the movement of monocytes, sometimes in tandem with neutrophils, along the paracellular pathways between adjacent epithelial cells. These data further support the pathophysiological role of BCSFB in promoting the recruitment of inflammatory cells to the injured brain.