TY - JOUR A1 - Weiherer, Maximilian A1 - Eigenberger, Andreas A1 - Egger, Bernhard A1 - Brébant, Vanessa A1 - Prantl, Lukas A1 - Palm, Christoph T1 - Learning the shape of female breasts: an open-access 3D statistical shape model of the female breast built from 110 breast scans JF - The Visual Computer N2 - We present the Regensburg Breast Shape Model (RBSM)—a 3D statistical shape model of the female breast built from 110 breast scans acquired in a standing position, and the first publicly available. Together with the model, a fully automated, pairwise surface registration pipeline used to establish dense correspondence among 3D breast scans is introduced. Our method is computationally efficient and requires only four landmarks to guide the registration process. A major challenge when modeling female breasts from surface-only 3D breast scans is the non-separability of breast and thorax. In order to weaken the strong coupling between breast and surrounding areas, 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. To underline the expressiveness of the proposed model, we finally demonstrate in two showcase applications how the RBSM can be used for surgical outcome simulation and the prediction of a missing breast from the remaining one. Our model is available at https://www.rbsm.re-mic.de/. KW - Statistical shape model KW - Non-rigid surface registration KW - Breast imaging KW - Surgical outcome simulation KW - Breast reconstruction surgery Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-30506 N1 - Corresponding author: Christoph Palm N1 - Zugehörige arXiv-Publikation: https://opus4.kobv.de/opus4-oth-regensburg/frontdoor/index/index/docId/2023 VL - 39 IS - 4 SP - 1597 EP - 1616 PB - Springer Nature ER - TY - JOUR A1 - Brébant, Vanessa A1 - Weiherer, Maximilian A1 - Noisser, Vivien A1 - Seitz, Stephan A1 - Prantl, Lukas A1 - Eigenberger, Andreas T1 - Implants Versus Lipograft: Analysis of Long-Term Results Following Congenital Breast Asymmetry Correction JF - Aesthetic Plastic Surgery N2 - Aims Congenital breast asymmetry represents a particular challenge to the classic techniques of plastic surgery given the young age of patients at presentation. This study reviews and compares the long-term results of traditional breast augmentation using silicone implants and the more innovative technique of lipografting. Methods To achieve this, we not only captured subjective parameters such as satisfaction with outcome and symmetry, but also objective parameters including breast vol-ume and anthropometric measurements. The objective examination was performed manually and by using the Vectra H2 photogrammetry scanning system. Results Differences between patients undergoing either implant augmentation or lipograft were revealed not to be significant with respect to patient satisfaction with surgical outcome (p= 0.55) and symmetry (p= 0.69). Furthermore, a breast symmetry of 93 % was reported in both groups. Likewise, no statistically significant volume difference between the left and right breasts was observed in both groups (p\0.41). However, lipograft patients needed on average 2.9 procedures to achieve the desired result, compared with 1.3 for implant augmentation. In contrast, patients treated with implant augmentation may require anumber of implant changes during their lifetime. Conclusion Both methods may be considered for patients presenting with congenital breast asymmetry. KW - Congenital Breast Asymmetry KW - 3D volumetry KW - Autologous fat injections KW - Three-dimensional imaging KW - Lipograft Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-32404 N1 - Corresponding author der OTH Regensburg: Vanessa Brébant VL - 46 SP - 2228 EP - 2236 PB - Springer Nature ER - TY - JOUR A1 - Noisser, Vivien A1 - Eigenberger, Andreas A1 - Weiherer, Maximilian A1 - Seitz, Stephan A1 - Prantl, Lukas A1 - Brébant, Vanessa T1 - Surgery of congenital breast asymmetry - which objective parameter influences the subjective satisfaction with long-term results JF - Archives of Gynecology and Obstetrics N2 - 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. KW - Congenital breast asymmetry KW - Poland syndrome KW - Lipofilling KW - Silicone implant KW - 3D volumetry Y1 - 2021 U6 - https://doi.org/10.1007/s00404-021-06218-0 PB - Springer Nature ER - TY - JOUR A1 - Bartsch, Alexander A1 - Eigenberger, Andreas A1 - Felthaus, Oliver A1 - Booth, Brian W. A1 - Krenkel, Lars A1 - Schratzenstaller, Thomas A1 - Prantl, Lukas T1 - Quantification of Cannula Influence on Negative Pressure in Syringe Assisted Liposuction JF - Plastic & Reconstructive Surgery N2 - To make the results of the autologous fat transfer more satisfactory, all parameters of suction, preparation, and reapplication must be well understood. Since syringe-assisted liposuction is frequently used for small-volume procedures, we quantified the influence of the cannula on negative pressure. For these experiments, we used a digital manometer to which a syringe and one of seven different cannulas were connected. Data was collected and analyzed using LabVIEW and Matlab. The volume of our measurement setup was calculated using Boyle-Mariotte's law to ease interpretation, which revealed a volume of 2.82 ± 0.03 mL. We demonstrate that the volume of the measurement setup significantly affects the measurement results. Consequently, we accounted for this factor and calculated the theoretical values accordingly. Statistical analysis shows a significant influence on negative pressure across different cannulas, except for two pairs, which had minimal volume differences. Exemplary, for cannulas with volumes under 1.75 mL, a 2 mL syringe plunger pull was sufficient to create a - 0.5 bar (- 14.8 inHg) negative pressure. The present data indicate that the size of the suction cannula must be considered in syringe-assisted suction to ensure a specific negative pressure is not exceeded. Other research groups have demonstrated that adipocyte vitality and the amount of stromal vascular fraction are reduced by excessively strong negative pressure. Y1 - 2025 U6 - https://doi.org/10.1097/PRS.0000000000012477 SN - 0032-1052 PB - American Society of Plastic Surgeons ER - TY - THES A1 - Eigenberger, Andreas T1 - Die Auswirkungen der mechanischen Kräfte eines innovativen Operationsverfahrens für die intraoperative Gewebezubereitung bei autologem Fetttransfer auf das Fettgewebe und dessen Stammzellen Y1 - 2024 SP - 235 Blätter CY - Regensburg ER -