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PURPOSE:
The purpose of this study was to find a suitable method of labelling cartilage samples for the measurement of distraction distances in biomechanical testing.
METHODS:
Samples of bovine cartilage were labelled using five different methods: hydroquinone and silver nitrate (AgNO3), potassium permanganate (KMnO4) with sodium thiosulphate (Na2S2O3), India ink, heat, and laser energy. After the labelling, we analysed the cartilage samples with regard to cytotoxity by histochemical staining with ethidiumbromide homodimer (EthD-1) and calcein AM. Furthermore, we tested cartilages labelled with India ink and heat in a T-peel test configuration to analyse possible changes in the mechanical behaviour between marked and unlabelled samples.
RESULTS:
Only the labelling methods with Indian ink or a heated needle showed acceptable results in the cytotoxity test with regard to labelling persistence, accuracy, and the influence on consistency and viability of the chondrocytes. In the biomechanical T-peel configuration, heat-labelled samples collapsed significantly earlier than unlabelled samples.
CONCLUSION:
Labelling bovine cartilage samples with Indian ink in biomechanical testing is a reliable, accurate, inexpensive, and easy-to-perform method. This labelling method influenced neither the biomechanical behaviour nor the viability of the tissue compared to untreated bovine cartilage.
Meniscal tears in the avascular zone have a poor self-healing potential, however partial meniscectomy predisposes the knee for early osteoarthritis. Tissue engineering with mesenchymal stem cells and a hyaluronan collagen based scaffold is a promising approach to repair meniscal tears in the avascular zone. 4 mm longitudinal meniscal tears in the avascular zone of lateral menisci of New Zealand White Rabbits were performed. The defect was left empty, sutured with a 5-0 suture or filled with a hyaluronan/collagen composite matrix without cells, with platelet rich plasma or with autologous mesenchymal stem cells. Matrices with stem cells were in part precultured in chondrogenic medium for 14 days prior to the implantation. Menisci were harvested at 6 and 12 weeks. The developed repair tissue was analyzed macroscopically, histologically and biomechanically. Untreated defects, defects treated with suture alone, with cell-free or with platelet rich plasma seeded implants showed a muted fibrous healing response. The implantation of stem cell-matrix constructs initiated fibrocartilage-like repair tissue, with better integration and biomechanical properties in the precultured stem cell-matrix group. A hyaluronan-collagen based composite scaffold seeded with mesenchymal stem cells is more effective in the repair avascular meniscal tear with stable meniscus-like tissue and to restore the native meniscus.
Vitamin C is an essential nutrient for humans and is involved in a plethora of health-related functions. Several studies have shown a connection between vitamin C intake and an improved resistance to infections that involves the immune system. However, the body cannot store vitamin C and both the elevated oral intake, and the intravenous application have certain disadvantages. In this study, we wanted to show a new formulation for the liposomal packaging of vitamin C. Using freeze etching electron microscopy, we show the formed liposomes. With a novel approach of post-processing procedures of real-time sonography that combines enhancement effects by contrast-like ultrasound with a transducer, we wanted to demonstrate the elevated intestinal vitamin C resorption on four participants. With the method presented in this study, it is possible to make use of the liposomal packaging of vitamin C with simple household materials and equipment for intake elevation. For the first time, we show the enhanced resorption of ingested liposomes using microbubble enhanced ultrasound imaging.
Background:
Lipofilling is one of the most often performed surgical procedures in plastic and reconstructive surgery. Lipoaspirates provide a ready source of stem cells and secreted factors that contribute to neoangiogenesis and fat graft survival. However, the regulations about the enrichment of these beneficial cells and factors are ambiguous. In this study, the authors tested whether a combination of centrifugation and homogenization allowed the enrichment of viable stem cells in lipoaspirates through the selective removal of tumescent solution, blood, and released lipids without significantly affecting the cell secretome.
Methods:
Human lipoaspirate was harvested from six different patients using water jet–assisted liposuction. Lipoaspirate was homogenized by first centrifugation (3584 rpm for 2 minutes), shear strain (10 times intersyringe processing), and second centrifugation (3584 rpm for 2 minutes). Stem cell enrichment was shown by cell counting after stem cell isolation. Lipoaspirate from different processing steps (unprocessed, after first centrifugation, after homogenization, after second centrifugation) was incubated in serum-free cell culture medium for mass spectrometric analysis of secreted proteins.
Results:
Lipoaspirate homogenization leads to a significant 2.6 ± 1.75-fold enrichment attributable to volume reduction without reducing the viability of the stem cells. Protein composition of the secretome did not change significantly after tissue homogenization. Considering the enrichment effects, there were no significant differences in the protein concentration of the 83 proteins found in all processing steps.
Conclusions:
Stem cells can be enriched mechanically without significantly affecting the composition of secreted proteins. Shear-assisted enrichment of lipoaspirate constitutes no substantial manipulation of the cells’ secretome.
Background
Breast reconstruction is an important coping tool for patients undergoing a mastectomy. There are numerous surgical techniques in breast reconstruction surgery (BRS). Regardless of the technique used, creating a symmetric outcome is crucial for patients and plastic surgeons. Three-dimensional surface imaging enables surgeons and patients to assess the outcome’s symmetry in BRS. To discriminate between autologous and alloplastic techniques, we analyzed both techniques using objective optical computerized symmetry analysis. Software was developed that enables clinicians to assess optical breast symmetry using three-dimensional surface imaging.
Methods
Twenty-seven patients who had undergone autologous (n = 12) or alloplastic (n = 15) BRS received three-dimensional surface imaging. Anthropomorphic data were collected digitally using semiautomatic measurements and automatic measurements. Automatic measurements were taken using the newly developed software. To quantify symmetry, a Symmetry Index is proposed.
Results
Statistical analysis revealed that there is no dif- ference in the outcome symmetry between the two groups (t test for independent samples; p = 0.48, two-tailed).
Conclusion
This study’s findings provide a foundation for qualitative symmetry assessment in BRS using automatized digital anthropometry. In the present trial, no difference in the outcomes’ optical symmetry was detected between autologous and alloplastic approaches.
"Topographic Shift": a new digital approach to evaluating topographic changes of the female breast
(2021)
Purpose
To assess precise topographic changes of the breast, objective documentation and evaluation of pre- and postoperative results are crucial. New technologies for mapping the body using digital, three-dimensional surface measurements have offered novel ways to numerically assess the female breast. Due to the lack of clear demarcation points of the breast contour, the selection of landmarks on the breast is highly dependent on the examiner, and, therefore, is prone to error when conducting before-after comparisons of the same breast. This study describes an alternative to volumetric measurements, focusing on topographic changes of the female breast, based on three-dimensional scans.
Method
The study was designed as an interventional prospective study of 10 female volunteers who had planned on having aesthetic breast augmentation with anatomical, textured implants. Three dimensional scans of the breasts were performed intraoperatively, first without and then with breast implants. The topographic change was determined as the mean distance between two three-dimensional layers before and after augmentation. This mean distance is defined as the Topographic Shift. Results The mean implant volume was 283 cc (SD = 68.6 cc, range = 210-395 cc). The mean Topographic Shift was 7.4 mm (SD = 1.9 mm, range = 4.8-10.7 mm). The mean Topographic Shifts per quadrant were: I: 8.0 mm (SD = 3.3 mm); II: 9.2 mm (SD = 3.1 mm); III: 6.9 mm (SD = 3.5 mm); IV: 1.9 mm (SD = 4.3 mm).
Conclusion
The Topographic Shift, describing the mean distance between two three-dimensional layers (for example before and after a volume changing therapy), is a new approach that can be used for assessing topographic changes of a body area. It was found that anatomical, textured breast implants cause a topographic change, particularly on the upper breast, in quadrant II, the decollete.
Purpose
Congenital breast asymmetry is a serious gynecological malformation for affected patients. The condition hits young women in puberty and is associated with socio-esthetic handicap, depression, and psychosexual problems. Surgical treatment is usually early in the patient's lifetime, so a long-term sustainable solution is important. Although postoperative outcome has been evaluated in several studies before, this study is the first to analyze which objective parameters have the greatest influence on subjective satisfaction with long-term results.
Methods
Thirty-four patients diagnosed with congenital breast asymmetry that underwent either lipofilling or implant therapy between the years of 2008 to 2019 were examined. On average, our collective comprised patients seven years after surgery. Data were mainly gathered through manual measurements, patient-reported outcome measures (Breast Q™), and breast volumetry based on 3D scans (Vectra® H2, Canfield Scientific).
Results
Among all analyzed parameters, only areolar diameter correlated significantly negatively with the subjective outcome satisfaction of the patient. Regarding the subjective assessment of postoperative satisfaction with similarity of the breasts, again the mean areolar diameter, but also the difference in areolar diameter and breast volume between the right and left breasts correlated significantly negatively.
Conclusion
Areolar diameter was revealed as being a significant factor influencing subjective long-term satisfaction in breast asymmetry patients. Moreover, 3D volumetry proves to be an effective tool to substantiate subjective patient assessments. Our findings may lead to further improvements to surgical planning and will be expanded in further studies.
We present the Regensburg Breast Shape Model (RBSM) – a 3D statistical shape model of the female breast built from 110 breast scans, and the first ever publicly available. Together with the model, a fully automated, pairwise surface registration pipeline used to establish correspondence among 3D breast scans is introduced. Our method is computationally efficient and requires only four landmarks to guide the registration process. In order to weaken the strong coupling between breast and thorax, we propose to minimize the variance outside the breast region as much as possible. To achieve this goal, a novel concept called breast probability masks (BPMs) is introduced. A BPM assigns probabilities to each point of a 3D breast scan, telling how likely it is that a particular point belongs to the breast area. During registration, we use BPMs to align the template to the target as accurately as possible inside the breast region and only roughly outside. This simple yet effective strategy significantly reduces the unwanted variance outside the breast region, leading to better statistical shape models in which breast shapes are quite well decoupled from the thorax. The RBSM is thus able to produce a variety of different breast shapes as independently as possible from the shape of the thorax. Our systematic experimental evaluation reveals a generalization ability of 0.17 mm and a specificity of 2.8 mm for the RBSM. Ultimately, our model is seen as a first step towards combining physically motivated deformable models of the breast and statistical approaches in order to enable more realistic surgical outcome simulation.
Purpose: In this trial, we used a previously developed prototype software to assess aesthetic results after reconstructive surgery for congenital breast asymmetry using automated anthropometry. To prove the consensus between the manual and automatic digital measurements, we evaluated the software by comparing the manual and automatic measurements of 46 breasts.
Methods: Twenty-three patients who underwent reconstructive surgery for congenital breast asymmetry at our institution were examined and underwent 3D surface imaging. Per patient, 14 manual and 14 computer-based anthropometric measurements were obtained according to a standardized protocol. Manual and automatic measurements, as well as the previously proposed Symmetry Index (SI), were compared.
Results: The Wilcoxon signed-rank test revealed no significant differences in six of the seven measurements between the automatic and manual assessments. The SI showed robust agreement between the automatic and manual methods.
Conclusion: The present trial validates our method for digital anthropometry. Despite the discrepancy in one measurement, all remaining measurements, including the SI, showed high agreement between the manual and automatic methods. The proposed data bring us one step closer to the long-term goal of establishing robust instruments to evaluate the results of breast surgery.
BACKGROUND: Autologous fat grafting (AFG) has been established over the past two decades as an additive technique during and after breast reconstruction. Complete reconstruction of the breast mound with AFG alone represents an exceptional technique that has been published mostly in case reports or in studies with limited cases.The purpose of this study is to investigate the influence of three different techniques for breast reconstruction on the recovery of skin sensitivity at the reconstructed breast.
METHODS: The study included 30 patients after mastectomy following breast cancer. Three groups were examined: A) breast reconstruction by autologous fat grafting (AFG), B) breast reconstruction by deep inferior epigastric artery perforator flap (DIEP) and C) breast reconstruction by expander/implant (TE).Biometric data were compared; sensitivity tests were performed using Semmes-Weinstein monofilaments.The non-operated, healthy contralateral breasts of the patients were used as a reference.
RESULTS: While the traditional reconstruction techniques by microsurgical anastomosed perforator flap or expander/implant showed a strongly decreased or completely missing sensitivity of the skin, the tests after reconstruction by AFG represented high values of sensory recovery, which came close to the reference group of non-operated breasts.
CONCLUSION: To our knowledge, this is the first study to compare skin sensitivity after AFG-based reconstruction to established techniques for breast reconstruction. We could demonstrate in a limited group of patients, that breast reconstruction by autologous fat grafting can achieve higher values of skin sensitivity compared to traditional techniques.