Alexandru Tuca

Comparison of Matrigel and Matriderm as a carrier for human amnion-derived mesenchymal stem cells in wound healing

Amnion-derived mesenchymal stem cells (AMSC) are a promising tool in regenerative medicine. Here we evaluated the utility of Matrigel and Matriderm as carrier for the topical application of AMSC to mice skin wounds. In both application forms, AMSC promoted neovascularization of the wound area. Matrigel proved as excellent matrix for AMSC and immigrating mouse cells, but the solid Matriderm enabled a more adequate positioning of AMSC into the wound. Although AMSC did not attach to Matriderm, they reliably induced wound reduction. Thus, a combined administration of AMSC/Matriderm could be beneficial to potentiate the encouraging effects on wound healing.

BurnCase 3D software validation study: Burn size measurement accuracy and inter-rater reliability

OBJECTIVE The aim of this study was to compare the accuracy of burn size estimation using the computer-assisted software BurnCase 3D (RISC Software GmbH, Hagenberg, Austria) with that using a 2D scan, considered to be the actual burn size. METHODS Thirty artificial burn areas were pre planned and prepared on three mannequins (one child, one female, and one male). Five trained physicians (raters) were asked to assess the size of all wound areas using BurnCase 3D software. The results were then compared with the real wound areas, as determined by 2D planimetry imaging. To examine inter-rater reliability, we performed an intraclass correlation analysis with a 95% confidence interval. RESULTS The mean wound area estimations of the five raters using BurnCase 3D were in total 20.7±0.9% for the child, 27.2±1.5% for the female and 16.5±0.1% for the male mannequin. Our analysis showed relative overestimations of 0.4%, 2.8% and 1.5% for the child, female and male mannequins respectively, compared to the 2D scan. The intraclass correlation between the single raters for mean percentage of the artificial burn areas was 98.6%. There was also a high intraclass correlation between the single raters and the 2D Scan visible. CONCLUSION BurnCase 3D is a valid and reliable tool for the determination of total body surface area burned in standard models. Further clinical studies including different pediatric and overweight adult mannequins are warranted.

Standardizing the complication rate after breast reduction using the Clavien-Dindo classification

Background. Published complication rates for breast reduction surgery, also known as reduction mammaplasty, vary between 4% and 54%. This wide range of complication rates could be attributable to the lack of a standardized classification of complications in plastic surgery. The aim of this study was to analyze our single‐center complication rates after reduction mammaplasty using the Clavien‐Dindo classification. Methods. We performed a retrospective chart review studying 804 patients between the ages of 18 and 81 years old who underwent breast reduction between 2005 and 2015 at our institution. Patients with a history of breast cancer, a previous breast operation, who did not undergo bilateral reduction mammaplasty, or who required systemic immunodeficiency/immunosuppressive drugs were excluded from our analysis. Complications were classified according to the Clavien‐Dindo classification from Grades I to V. Results. A total of 486 patients met the inclusion criteria for the analysis. Patients had an age (mean ± standard deviation) of 39 ± 13 years and a body mass index of 26 ± 4 kg/m2. Median follow‐up was 274 days (interquartile range: 90.5–378). The overall rate of complications of reduction mammaplasty was 63%, with the majority of those being Grades I (48%) and II (9%), comprising 92% of all the complications. Operative revisions were required in 6% (1% Grade IIIA and 5% Grade IIIB). There were no complications graded in categories IV and V. Conclusion. Although complications occurred in more than half of the cases, the majority did not require operative reintervention. The Clavien‐Dindo classification can classify the severity of complications and serve as a benchmark to compare complication rates between different practices. We believe that grading of complications should distinguish between those that do and do not require operative reinterventions.

First Experience Using Contrast‐enhanced Ultrasound to Evaluate Vascularisation of Acellular Dermal Matrices after Implant‐Based Breast Reconstruction

Acellular dermal matrices (ADM) have been used frequently in therapeutic and prophylactic breast procedures. To date there have been no reports on vascularisation of ADMs and formation of tissue around them as seen with modern non‐invasive imaging techniques such as contrast‐enhanced ultrasound (CEUS). In this case series, we used CEUS to investigate the features of ADM in relation to vascular ingrowth and scaffold for “new” tissue formation. This is a retrospective evaluation of patients who underwent successful skin‐ and nipple‐sparing mastectomy (SSM, NSM) with immediate IBBR using ADM from May 31, 2010, through December 28, 2012. Over a 24‐month period, 16 patients, with an average age of 44 years (range 27–70 years), were evaluated with CEUS. No contrast agent allergies or side effects were reported for the ultrasound examination. After contrast agent injection (1–18 months postoperatively), homogeneous normal enhancement in the ADM and peripheral region with physiological tissue formation was seen in all patients. In this small study, the most obvious contribution of CEUS is the in vivo evaluation of vascular ingrowth and tissue formation after IBBR with ADM after follow‐up of 1–18 months postoperatively.

Complications in tissue expansion: A logistic regression analysis for risk factors

BACKGROUND Tissue expansion is frequently used in reconstructive surgery. Although the surgical procedure is typically considered simple, reported complication rates of tissue expansions exceed 40%. There is little evidence concerning risk factors for complications in tissue expansion in body regions other than breast. The aim was to determine risk factors for complications in non-breast tissue expansion. METHODS 34 patients treated with subcutaneous tissue expanders between 2005 and 2014 were analyzed. Demographic data, body-mass index (BMI), mean arterial blood pressure (MAP), treatment indications, expansion site, previous expansion therapies in the same body region, smoking history, as well as expander characteristics (shape, volume, and filling mechanism) were ascertained. Complications were assessed and ranked according to severity based on the Clavien-Dindo classification. Binary logistic regression analysis adjusted for clinical characteristics was used. A p<0.05 was considered as statistically significant. RESULTS Complications were observed in 26 out of 71 expanders analyzed (36.6%), of whom 10 led to therapy failure. Expanders used in the limbs, female gender, and high expander volume turned out as significant risk factors. Patients with both a high MAP and low BMI developed tissue necrosis significantly more often (p=0.002). The use of tissue expansion after a burn was not associated with an increased risk for complications. CONCLUSIONS This is the first study revealing female gender and low BMI as risk factors in tissue expander surgery. Thus, careful patient selection is mandatory to avoid complications in tissue expansion. Burn patients do not develop complications more often.

What can we learn from sonication results of breast implants

Background Different research groups have identified microorganisms on breast implants by sonication with significant correlation to the rate of capsular contracture. This substantiated the hypothesis of an infectious etiology of capsular contracture. However, no clinical consequence has been drawn from these results yet. Aim of this study was to review sonication results from breast implants and to evaluate the current preoperative antibiotic regime for breast-implant surgery. Methods We compared breast implant sonication culture results from published reports and our own database. Current perioperative antibiotic recommendations were compared with the susceptibility profile of the found organisms. Results We found Coagulase-negative staphylococci and Propionibacteria to be the main group of microorganism found by sonication on explanted breast implants. Most guidelines recommend cephalosporins for preoperative antibiotical prophylaxis for breast-implant surgery. Conclusion There is a discrepancy between antibiotic activity of commonly used antibiotics for preoperative prophylaxis of surgical site infections, and microorganisms found by sonication on breast implants, suspected to trigger the formation of capsular contracture. A targeted antibiotic prophylaxis for breast implant surgery with glycopeptides (e.g. Vancomycin) should be considered for the prevention of capsular contracture.