Faculty Bibliography

BACKGROUND:Recently, a strategy for treating stroke directly at the emergency site was developed. It was based on the use of an ambulance equipped with a scanner, a point-of-care laboratory, and telemedicine capabilities (Mobile Stroke Unit). Despite demonstrating a marked reduction in the delay to thrombolysis, this strategy is criticized because of potentially unacceptable costs. METHODS:We related the incremental direct costs of prehospital stroke treatment based on data of the first trial on this concept to one year direct cost savings taken from published research results. Key parameters were configuration of emergency medical service personnel, operating distance, and population density. Model parameters were varied to cover 5 different relevant emergency medical service scenarios. Additionally, the effects of operating distance and population density on benefit-cost ratios were analyzed. RESULTS:Benefits of the concept of prehospital stroke treatment outweighed its costs with a benefit-cost ratio of 1.96 in the baseline experimental setting. The benefit-cost ratio markedly increased with the reduction of the staff and with higher population density. Maximum benefit-cost ratios between 2.16 and 6.85 were identified at optimum operating distances in a range between 43.01 and 64.88 km (26.88 and 40.55 miles). Our model implies that in different scenarios the Mobile Stroke Unit strategy is cost-efficient starting from an operating distance of 15.98 km (9.99 miles) or from a population density of 79 inhabitants per km2 (202 inhabitants per square mile). CONCLUSION/CONCLUSIONS:This study indicates that based on a one-year benefit-cost analysis that prehospital treatment of acute stroke is highly cost-effective across a wide range of possible scenarios. It is the highest when the staff size of the Mobile Stroke Unit can be reduced, for example, by the use of telemedical support from hospital experts. Although efficiency is positively related to population density, benefit-cost ratios can be greater than 1 even in rural settings.

The normal growth and development of the skull is a tightly regulated process that occurs along the osteogenic interfaces of the cranial sutures. Here, the borders of the calvarial bones and neighboring tissues above and below, function as a complex. Through coordinated remodeling efforts of bone deposition and resorption, the cranial sutures maintain a state of patency from infancy through early adulthood as the skull continues to grow and accommodate the developing brain's demands for expansion. However, when this delicate balance is disturbed, a number of pathologic conditions ensue; and if left uncorrected, may result in visual and neurocognitive impairments. A prime example includes craniosynostosis, or premature fusion of one or more cranial and/or facial suture(s). At the present time, the only therapeutic measure for craniosynostosis is surgical correction by cranial vault reconstruction. However, elegant studies performed over the past decade have identified several genes critical for the maintenance of suture patency and induction of suture fusion. Such deeper understandings of the pathogenesis and molecular mechanisms that regulate suture biology may provide necessary insights toward the development of non-surgical therapeutic alternatives for patients with cranial suture defects. In this review, we discuss the intricate cellular and molecular interplay that exists within the suture among its three major components: dura mater, osteoblastic related molecular pathways and osteoclastic related molecular pathways.

Reconstruction of craniofacial defects in children presents several challenges that are not encountered in the adult population. Autologous bone grafts have long been the criterion standard for repairing these defects. Recently, several new materials and techniques have expanded our arsenal of reconstructive options. In this clinical report, we describe the use of both particulate bone grafting and demineralized bone matrix together to repair craniofacial defects encountered in pediatric patients.

BACKGROUND:Although platelet-rich plasma (PRP) is used clinically to augment tendon healing, bone morphogenetic protein-13 (BMP13) may provide a better therapeutic avenue to improve early tendon healing and repair. HYPOTHESIS/OBJECTIVE:Exogenous expression of BMP13 in tenocytes will up-regulate genes involved in tendon healing. Direct delivery of adenovirus-mediated BMP13 (AdBMP13) into the injured rat supraspinatus tendon will increase biomechanical properties. STUDY DESIGN/METHODS:Controlled laboratory study. METHODS:Exogenous expression of BMP13 and the major growth factors in PRP (transforming growth factor-β1 [TGF-β1], vascular endothelial growth factor-A [VEGF-A], and platelet-derived growth factor-BB [PDGF-BB]) was accomplished by using recombinant adenoviral vectors. The expression of tendon- and matrix-associated genes in growth factor-treated tenocytes was analyzed by use of semiquantitative reverse-transcription polymerase chain reaction. A total of 32 rats with supraspinatus defect were divided into 4 groups and injected with adenovirus-containing green fluorescent protein (AdGFP; negative control), PRP, AdBMP13, or PRP+AdBMP13. All rats were sacrificed at 2 weeks after surgery, and tendons were harvested for biomechanical testing and histologic analysis. RESULTS:BMP13 up-regulated type III collagen expression compared with AdGFP control and PRP growth factors (P < .01). BMP13 and PRP growth factors each up-regulated fibronectin expression (P < .01). There was an increase in stress to failure in each of the 3 treatment groups (P < .05 for PRP; P < .01 for AdBMP13 or PRP+AdBMP13) compared with AdGFP control. AdBMP13 demonstrated higher stress to failure than did the PRPs (P < .01). The addition of PRP did not increase the BMP13-enhanced stress to failure or stiffness. The biomechanical results were further supported by histologic analysis of the retrieved samples. CONCLUSION/CONCLUSIONS:Exogenous expression of BMP13 enhances tendon healing more effectively than PRP as assessed by tendon- and matrix-associated gene expression, biomechanical testing, and histologic analysis. CLINICAL RELEVANCE/CONCLUSIONS:While PRP is used in the clinical setting, BMP13 may be explored as a superior biofactor to improve rotator cuff tendon healing and reduce the incidence of retears.

Nasal septal defects can be challenging to repair, given their location, size, and the unique, tri-layered structure of the septum, which includes a thin piece of cartilage positioned between mucosal layers. The report herein presents a case of a 47 year-old woman with a large symptomatic nasal septal perforation, despite saline irrigations and ointment. Placement of a septal button or a traditional surgical approach was not considered because of the extremely large nature of the perforation. We describe the use of a tri-layered fascia lata flap prelaminated with buccal mucosa grafts to successfully repair this complicated defect. Subsequent follow-up visits showed complete repair of the defect and patent nasal passages, without the need for any debulking procedures. Based on these results, we conclude that a prelaminated fascia lata flap is a good reconstructive option for large, complex nasal septal defects, bringing thin, healthy mucosalized tissue to the defect and minimizing future surgical procedures.

A 28-year-old otherwise healthy man was admitted to the burn center for treatment of toxic epidermal necrolysis (TEN) involving 90% of the TBSA and oropharynx. On hospital day 8, his cutaneous lesions were healing well, but he developed respiratory distress, fever, and abdominal distension. Computerized tomography demonstrated distended bowel, pneumatosis intestinalis, and portal venous gas. He underwent emergent celiotomy. Patchy areas of nonperforated necrosis along the jejunum and ileum were present. No mechanical or embolic source of ischemia could be identified. A 120-cm segment of ischemic small bowel was resected and the abdomen was closed temporarily. On planned "second look" the following day, no further disease was encountered and intestinal continuity was restored. Tube feeds were then initiated and the patient's recovery was uneventful thereafter. Although traditionally considered a skin disorder, TEN may be more accurately described as a disorder affecting the junction of an epithelium and its supporting tissue. It is most prominently manifested at the epidermal-dermal junction, but epithelial-submucosal junctions are also affected. The ocular, respiratory, genitourinary, and gastrointestinal manifestations of TEN are variable and incompletely understood. This disease is rooted in immunological dysfunction and the small bowel is rich in immunologically active tissue; Peyer patches and lymph nodes abound. Clinicians should be vigilant for gastrointestinal tract involvement, which is potentially treatable with resection of the ischemic bowel. The authors suspect that, given the critical condition of many TEN patients, bowel symptoms may be incorrectly attributed to global hypoperfusion and sepsis.

BACKGROUND:The technique of delayed-immediate breast reconstruction includes immediate insertion of a tissue expander, post-mastectomy radiation, followed by reconstruction. The aesthetic benefits of delayed-immediate reconstruction compared to delayed reconstruction are postulated but remain unproven. The purpose of this study was to compare aesthetic outcomes in patients following delayed and delayed-immediate autologous breast reconstruction. METHODS:A retrospective analysis was performed of all patients who underwent delayed or delayed-immediate autologous breast reconstruction by the senior author from 2005 to 2011. Postoperative photographs were used to evaluate aesthetic outcomes: skin quality, scar formation, superior pole contour, inferior pole contour, and overall aesthetic outcome. Ten non-biased reviewers assessed outcomes using a 5-point Likert scale. Fisher's Exact and Wilcoxon-Mann-Whitney tests were used for comparative analysis. RESULTS:Patient age and body mass index were similar between delayed (n=20) and delayed-immediate (n=20) cohorts (P>0.05). Skin and scar quality was rated significantly higher in the delayed-immediate cohort (3.74 vs. 3.05, P<0.001 and 3.41 vs. 2.79, P<0.001; respectively). Assessment of contour-related parameters, superior pole and inferior pole, found significantly improved outcomes in the delayed-immediate cohort (3.67 vs. 2.96, P<0.001 and 3.84 vs. 3.06, P<0.001; respectively). Delayed-immediate breast reconstruction had a significantly higher overall score compared to delayed breast reconstructions (3.84 vs. 2.94, P<0.001). Smoking and the time interval from radiation to reconstruction were found to affect aesthetic outcomes (P<0.05). CONCLUSIONS:Preservation of native mastectomy skin may allow for improved skin/scar quality, breast contour, and overall aesthetic outcomes following a delayed-immediate reconstructive algorithm as compared to delayed breast reconstruction.