35 results on '"Christian Witzel"'
Search Results
2. [YIA] The influence of skin barrier disruption and melanin content on the formation of DNA lesions and radicals in ex vivo human skin induced by 233 nm far-UVC irradiation from LEDs
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Loris Busch, Johannes Schleusener, Daniela F. Zamudio Díaz, Marius Kröger, Silke B. Lohan, Paula Zwicker, Einfeldt Sven, Michael Kneissl, Anja A. Kühl, Christian Witzel, Holger Klose, Cornelia M. Keck, Axel Kramer, and Martina C. Meinke
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Physiology (medical) ,Biochemistry - Published
- 2022
3. Application of 233 nm far-UVC LEDs for eradication of MRSA and MSSA and risk assessment on skin models
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Paula Zwicker, Johannes Schleusener, Silke B. Lohan, Loris Busch, Claudia Sicher, Sven Einfeldt, Michael Kneissl, Anja A. Kühl, Cornelia M. Keck, Christian Witzel, Axel Kramer, and Martina C. Meinke
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Methicillin-Resistant Staphylococcus aureus ,Multidisciplinary ,Cell Survival ,Ultraviolet Rays ,Staphylococcus epidermidis ,Humans ,Dose-Response Relationship, Radiation ,Safety ,Radiation Dosage ,DNA Damage ,Skin - Abstract
A newly developed UVC LED source with an emission wavelength of 233 nm was proved on bactericidal efficacy and skin tolerability. The bactericidal efficacy was qualitatively analysed using blood agar test. Subsequently, quantitative analyses were performed on germ carrier tests using the MRSA strain DSM11822, the MSSA strain DSM799, S. epidermidis DSM1798 with various soil loads. Additionally, the compatibility of the germicidal radiation doses on excised human skin and reconstructed human epidermis was proved. Cell viability, DNA damage and production of radicals were assessed in comparison to typical UVC radiation from discharge lamps (222 nm, 254 nm) and UVB (280–380 nm) radiation for clinical assessment. At a dose of 40 mJ/cm2, the 233 nm light source reduced the viable microorganisms by a log10 reduction (LR) of 5 log10 levels if no soil load was present. Mucin and protein containing soil loads diminished the effect to an LR of 1.5–3.3. A salt solution representing artificial sweat (pH 8.4) had only minor effects on the reduction. The viability of the skin models was not reduced and the DNA damage was far below the damage evoked by 0.1 UVB minimal erythema dose, which can be regarded as safe. Furthermore, the induced damage vanished after 24 h. Irradiation on four consecutive days also did not evoke DNA damage. The radical formation was far lower than 20 min outdoor visible light would cause, which is classified as low radical load and can be compensated by the antioxidant defence system.
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- 2022
4. Over 30 Years of Pediatric Liver Transplantation at the Charité—Universitätsmedizin Berlin
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Simon, Moosburner, Leke, Wiering, Safak, Gül-Klein, Paul, Ritschl, Tomasz, Dziodzio, Nathanael, Raschzok, Christian, Witzel, Alexander, Gratopp, Stephan, Henning, Philip, Bufler, Moritz, Schmelzle, Georg, Lurje, Wenzel, Schöning, Johann, Pratschke, Brigitta, Globke, and Robert, Öllinger
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pediatric liver transplantation ,early allograft dysfunction ,survival ,600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit::610 Medizin und Gesundheit - Abstract
Background: Pediatric liver transplantation (LT) is the treatment of choice for children with end-stage liver disease and in certain cases of hepatic malignancies. Due to low case numbers, a technically demanding procedure, the need for highly specialized perioperative intensive care, and immunological, as well as infectious, challenges, the highest level of interdisciplinary cooperation is required. The aim of our study was to analyze short- and long-term outcomes of pediatric LT in our center. Methods: We conducted a retrospective single-center analysis of all liver transplantations in pediatric patients (≤16 years) performed at the Department of Surgery, Charité – Universitätsmedizin Berlin between 1991 and 2021. Three historic cohorts (1991–2004, 2005–2014 and 2015–2021) were defined. Graft- and patient survival, as well as perioperative parameters were analyzed. The study was approved by the institutional ethics board. Results: Over the course of the 30-year study period, 212 pediatric LTs were performed at our center. The median patient age was 2 years (IQR 11 years). Gender was equally distributed (52% female patients). The main indications for liver transplantation were biliary atresia (34%), acute hepatic necrosis (27%) and metabolic diseases (13%). The rate of living donor LT was 25%. The median cold ischemia time for donation after brain death (DBD) LT was 9 h and 33 min (IQR 3 h and 46 min). The overall donor age was 15 years for DBD donors and 32 years for living donors. Overall, respective 1, 5, 10 and 30-year patient and graft survivals were 86%, 82%, 78% and 65%, and 78%, 74%, 69% and 55%. One-year patient survival was 85%, 84% and 93% in the first, second and third cohort, respectively (p = 0.14). The overall re-transplantation rate was 12% (n = 26), with 5 patients (2%) requiring re-transplantation within the first 30 days. Conclusion: The excellent long-term survival over 30 years showcases the effectiveness of liver transplantation in pediatric patients. Despite a decrease in DBD organ donation, patient survival improved, attributed, besides refinements in surgical technique, mainly to improved interdisciplinary collaboration and management of perioperative complications.
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- 2022
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5. 427.2: Refinement of Hind Limb Allotransplantation in Mice: Introduction of a Novel Anticoagulation Treatment Protocol That Improves Overall Success Rate
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Barbara Kern, Friederike Martin, Anja Reutzel-Selke, Joerg Mengwasser, Edward Michaelis, Muhammad-Imtiaz Ashraf, Dietrich Polenz, Igor Sauer, Johann Pratschke, Christian Witzel, and Stefan Tullius
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Transplantation - Published
- 2022
6. Quantification and characterization of radical production in human, animal and 3D skin models during sun irradiation measured by EPR spectroscopy
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Carina Reble, Leonhard Zastrow, Ingeborg Beckers, Stephanie Albrecht, Hannah Pischon, Christian Witzel, Martina C. Meinke, Ceyda Kasim, Jürgen Lademann, Sarah Hedtrich, Lars Mundhenk, and Anja Elpelt
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0301 basic medicine ,Free Radicals ,Erythema ,Swine ,Ultraviolet Rays ,Radical ,Human skin ,medicine.disease_cause ,Models, Biological ,Biochemistry ,Skin Aging ,Cyclic N-Oxides ,Tissue Culture Techniques ,Mice ,03 medical and health sciences ,Imaging, Three-Dimensional ,0302 clinical medicine ,In vivo ,Physiology (medical) ,medicine ,Animals ,Humans ,Radiometry ,Skin ,chemistry.chemical_classification ,Reactive oxygen species ,integumentary system ,Electron Spin Resonance Spectroscopy ,Dose-Response Relationship, Radiation ,Oxygen ,Oxidative Stress ,030104 developmental biology ,chemistry ,Sunlight ,Biophysics ,Spin Labels ,medicine.symptom ,030217 neurology & neurosurgery ,Ex vivo ,Oxidative stress - Abstract
Sun radiation is indispensable to our health, however, a long term and high exposure could lead to erythema, premature skin aging and promotion of skin tumors. An underlying pathomechanism is the formation of free radicals. First, reactive oxygen species (*OH, *O2-) and then, secondary lipid oxygen species (C centered radicals, CCR) are formed. A high amount of free radicals results in oxidative stress with subsequent cell damage. In dermatological research different skin models are used, however, comparative data about the cutaneous radical formation are missing. In this study , the radical formation in porcine-, (SKH-1) murine-, human- ex vivo skin and reconstructed human skin (RHS) were investigated during simulated sun irradiation (305–2200 nm), with X-band EPR spectroscopy. The amount of radical formation was investigated with the spin probe PCA exposed to a moderate sun dose below one minimal erythema dose (MED, ~25 mJ/cm2 UVB) in all skin models. Furthermore, the *OH and *CCR radical concentrations were measured with the spin trap DMPO within 0–4 MED (porcine-, human skin and RHS). The highest amount of radicals was found in RHS followed by murine and porcine , and the lowest amount in human ex vivo skin. In all skin models , more *OH than CCR radicals were found at 0–4 MED. Additionally, this work addresses the limitations in the characterization with the spin trap DMPO. The measurements have shown that the most comparable skin model to in vivo human skin could differ depending on the focus of the investigation. If the amount of radial production is regarded, RHS seems to be in a similar range like in vivo human skin. If the investigation is focused on the radical type, porcine skin is most comparable to ex vivo human skin, at an irradiation dose not exceeding 1 MED. Here, no comparison to in vivo human skin is possible.
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- 2019
7. The adipofasciocutaneous gluteal fold perforator flap a versatile alternative choice for covering perineal defects
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G. B. Stark, Johann Pratschke, Philipp Manegold, Felix Aigner, Vincenzo Penna, Martin E. Kreis, Christian Witzel, Georgios Koulaxouzidis, Hannes P. Neeff, Florian Lampert, and Holger Bannasch
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Male ,medicine.medical_specialty ,Perineum ,Resection ,Abdominal wall ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Epidemiology ,Rectal Adenocarcinoma ,medicine ,Humans ,Fascia ,Rectus abdominis muscle ,Aged ,Skin ,Aged, 80 and over ,Postoperative Care ,business.industry ,Gastroenterology ,Anal Squamous Cell Carcinoma ,Middle Aged ,Plastic Surgery Procedures ,Hepatology ,Surgery ,medicine.anatomical_structure ,Adipose Tissue ,030220 oncology & carcinogenesis ,Buttocks ,Female ,030211 gastroenterology & hepatology ,business ,Perforator Flap ,Perforator flaps - Abstract
Perineal defects following the resection of anorectal malignancies are a reconstructive challenge. Flaps based on the rectus abdominis muscle have several drawbacks. Regional perforator flaps may be a suitable alternative. We present our experience of using the gluteal fold flap (GFF) for reconstructing perineal and pelvic defects. We used a retrospective chart review and follow-up examinations focusing on epidemiological, oncological (procedure and outcome), and therapy-related data. This included postoperative complications and their management, length of hospital stay, and time to heal. Twenty-two GFFs (unilateral n = 8; bilateral n = 7) were performed in 15 patients (nine women and six men; anal squamous cell carcinoma n = 8; rectal adenocarcinoma n = 7; mean age 65.5 + 8.2 years) with a mean follow-up time of 1 year. Of the cases, 73.3% were a recurrent disease. Microscopic tumor resection was achieved in all but one case (93.3%). Seven cases had no complications (46.7%). Surgical complications were classified according to the Clavien-Dindo system (grades I n = 2; II n = 2; IIIb n = 4). These were mainly wound healing disorders that did not affect mobilization or discharge. The time to discharge was 22 + 9.9 days. The oncological outcomes were as follows: 53.3% of the patients had no evidence of disease, 20% had metastatic disease, 20% had local recurrent disease, and one patient (6.7%) died of other causes. The GFF is a robust, reliable flap suitable for perineal and pelvic reconstruction. It can be raised quickly and easily, has an acceptable complication rate and donor site morbidity, and does not affect the abdominal wall.
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- 2019
8. Outcome after pediatric liver transplantation for staged abdominal wall closure with use of biological mesh—Study with long‐term follow‐up
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Maximilian Jara, Robert Öllinger, Paul Viktor Ritschl, Stephan Henning, Alexander Gratopp, Johann Pratschke, Wenzel Schöning, Philip Bufler, Anika Kästner, Friederike Martin, Brigitta Globke, Christian Witzel, Moritz Schmelzle, Tomasz Dziodzio, and Safak Gül-Klein
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Male ,medicine.medical_specialty ,biological mesh ,Long term follow up ,medicine.medical_treatment ,030232 urology & nephrology ,abdominal wall closure ,030230 surgery ,Liver transplantation ,Postoperative management ,Abdominal wall ,03 medical and health sciences ,Abdominal wall closure ,0302 clinical medicine ,Outcome Assessment, Health Care ,medicine ,Humans ,Incisional Hernia ,Surgical Wound Infection ,Acellular Dermis ,Hernia ,Retrospective Studies ,Transplantation ,Dermal collagen ,business.industry ,Abdominal Wall ,Graft Survival ,Infant, Newborn ,pediatric liver transplantation in infants ,Infant ,Abdominal Wound Closure Techniques ,Surgical Mesh ,medicine.disease ,porcine dermal collagen acellular graft ,Liver Transplantation ,Surgery ,medicine.anatomical_structure ,Pediatrics, Perinatology and Child Health ,Feasibility Studies ,Female ,Graft survival ,Collagen ,business ,600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit::610 Medizin und Gesundheit ,Follow-Up Studies - Abstract
Abdominal wall closure after pediatric liver transplantation (pLT) in infants may be hampered by graft-to-recipient size discrepancy. Herein, we describe the use of a porcine dermal collagen acellular graft (PDCG) as a biological mesh (BM) for abdominal wall closure in pLT recipients. Patients
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- 2020
9. CNS myeloid cells critically regulate heat hyperalgesia
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Christian Witzel, Roland E. Kälin, Frank L. Heppner, Kelly R. Miller, Stefanie Kälin, and Marina Jendrach
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Central Nervous System ,Male ,0301 basic medicine ,physiopathology [Central Nervous System] ,Hot Temperature ,pathology [Peripheral Nerves] ,Mice ,pathology [Hyperalgesia] ,0302 clinical medicine ,Peripheral Nerve Injuries ,physiology [Peptide Fragments] ,pathology [Spinal Cord Dorsal Horn] ,cytology [Microglia] ,Myeloid Cells ,pathology [Neuralgia] ,physiopathology [Spinal Cord Dorsal Horn] ,Microglia ,General Medicine ,Sciatic nerve injury ,physiology [Myeloid Cells] ,medicine.anatomical_structure ,Hyperalgesia ,Neuropathic pain ,medicine.symptom ,calcitonin gene related peptide (1-7) ,Research Article ,medicine.drug ,Ganciclovir ,Spinal Cord Dorsal Horn ,pathology [Peripheral Nerve Injuries] ,physiology [Calcitonin Gene-Related Peptide] ,Calcitonin Gene-Related Peptide ,Mice, Transgenic ,Calcitonin gene-related peptide ,physiopathology [Peripheral Nerve Injuries] ,03 medical and health sciences ,medicine ,Animals ,Peripheral Nerves ,ddc:610 ,physiopathology [Peripheral Nerves] ,physiopathology [Hyperalgesia] ,business.industry ,Nerve injury ,pathology [Myeloid Cells] ,medicine.disease ,Spinal cord ,Peptide Fragments ,physiology [Microglia] ,Mice, Inbred C57BL ,030104 developmental biology ,nervous system ,Calcitonin ,Neuralgia ,pathology [Central Nervous System] ,business ,Neuroscience ,030217 neurology & neurosurgery ,physiopathology [Neuralgia] - Abstract
Activation of non-neuronal microglia is thought to play a causal role in spinal processing of neuropathic pain. To specifically investigate microglia-mediated effects in a model of neuropathic pain and overcome the methodological limitations of previous approaches exploring microglia function upon nerve injury, we selectively ablated resident microglia by intracerebroventricular ganciclovir infusion into male CD11b-HSVTK–transgenic mice, which was followed by a rapid, complete, and persistent (23 weeks) repopulation of the CNS by peripheral myeloid cells. In repopulated mice that underwent sciatic nerve injury, we observed a normal response to mechanical stimuli, but an absence of thermal hypersensitivity ipsilateral to the injured nerve. Furthermore, we found that neuronal expression of calcitonin gene–related peptide (CGRP), which is a marker of neurons essential for heat responses, was diminished in the dorsal horn of the spinal cord in repopulated mice. These findings identify distinct mechanisms for heat and mechanical hypersensitivity and highlight a crucial contribution of CNS myeloid cells in the facilitation of noxious heat.
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- 2018
10. Barrier-disrupted skin: Quantitative analysis of tape and cyanoacrylate stripping efficiency by multiphoton tomography
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Alexa Patzelt, Monika Schäfer-Korting, Maxim E. Darvin, Martina C. Meinke, Jürgen Lademann, Christian Zoschke, Viktor V Nikolaev, Marius Kröger, Christian Witzel, and Pin Dong
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Swine ,Skin Absorption ,Stratum granulosum ,Pharmaceutical Science ,Human skin ,02 engineering and technology ,030226 pharmacology & pharmacy ,Stripping (fiber) ,Permeability ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,law ,Stratum corneum ,medicine ,Animals ,Humans ,Cyanoacrylates ,Skin ,integumentary system ,Chemistry ,Permeation ,021001 nanoscience & nanotechnology ,Autofluorescence ,medicine.anatomical_structure ,Cyanoacrylate ,Evaluation Studies as Topic ,Female ,0210 nano-technology ,Tomography, X-Ray Computed ,Ex vivo ,Biomedical engineering - Abstract
Numerous studies have employed tape stripping (TS) or cyanoacrylate stripping (CS) to induce skin barrier disruption of the stratum corneum (SC) in human and porcine skin. However, the thickness of the remaining SC and the respective changes of the skin permeability have been rarely quantified. By using high-resolution multiphoton tomography, about 5 µm thick SC was found remaining on human skin after the performance of 30 times TS or 2 times CS. 50 tape strips or 4 times CS removed the entire human SC, but on porcine skin 2–3 µm thick SC was still left. TS can only reach the transition zone between the SC and the stratum granulosum because of the limited adhesion, whereas CS was able to remove viable skin layers. Permeation investigations on porcine skin revealed that the apparent permeability coefficient of the hydrophilic nitroxide spin 2,5,5-Tetramethyl-1-pyrrolidinyloxy-3-carboxylic acid increased 15-, 18-, and 21-fold when the SC amount remaining in the skin was 30%, 16%, and 8%, respectively. It is recommended to use at most 30 times TS or 3 times CS to obtain ex vivo barrier-disrupted skin that mimics diseased skin. The study provides quantitative information for the utility of TS and CS in skin penetration research.
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- 2019
11. Surgical workflow for fully navigated high sacral amputation in sacral chordoma
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Felix Aigner, Simon Bayerl, Peter Vajkoczy, Christopher P. Ames, Johannes Goldberg, and Christian Witzel
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musculoskeletal diseases ,Adult ,medicine.medical_specialty ,Regional anatomy ,Sacrum ,medicine.medical_treatment ,Computed tomography ,Amputation, Surgical ,030218 nuclear medicine & medical imaging ,Workflow ,03 medical and health sciences ,0302 clinical medicine ,Germany ,medicine ,Chordoma ,Humans ,Pelvis ,Neuronavigation ,Spinal Neoplasms ,medicine.diagnostic_test ,business.industry ,Navigation system ,General Medicine ,medicine.disease ,medicine.anatomical_structure ,Treatment Outcome ,Amputation ,Surgery ,Female ,Neurology (clinical) ,Radiology ,Neurosurgery ,business ,Tomography, X-Ray Computed ,030217 neurology & neurosurgery ,Sacral Chordoma - Abstract
The method of choice for treatment of sacral chordomas is en bloc tumor removal via sacrectomy or sacral amputation in varying degrees depending on the initial tumor extent. Besides local tumor control, the preservation of neurological function is equally important to minimize postoperative bladder and bowel dysfunction. Removal of sacral tumors is complicated by the complex regional anatomy of the pelvis and the surrounding visceral and retroperitoneal structures. We aim to describe the surgical workflow for a fully navigated high sacral amputation facilitated by integration of an intraoperative computed tomography (iCT)-based spinal navigation system. An iCT-based spinal navigation system (AIRO® CT scanner, Brainlab AG, Feldkirchen, Germany) was used to perform intraoperative navigation with an image-guidance system and infrared tracking camera (BrainLab CurveTM, Brainlab AG, Feldkirchen, Germany) in combination with the spinal navigation set by Brainlab (Brainlab AG, Feldkirchen, Germany) to perform a fully navigated high sacral amputation. We demonstrate the successful implementation of iCT-based spinal navigation during high sacral amputation and the key advantages of this technique throughout the surgery. iCT-based spinal navigation is a useful complementing technique for en bloc high sacral amputations that renders the surgery safer and more accurate.
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- 2019
12. Risk Factor Analysis for Flap and Donor Site Related Complications in 1274 DIEP Flaps - Retrospective Single Center Study
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Sonia, Fertsch, Beatrix, Munder, Christoph, Andree, Christian, Witzel, Peter, Stambera, Tino, Schulz, Mazen, Hagouan, Lukas, Gruter, Birgit, Aufmesser, Katinka, Staemmler, Julia, Kornetka, Mohammed, Aldeeri, Katrin, Seidenstucker, Alina, Abu-Ghazaleh, and Andreas, Wolter
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Mammaplasty ,Breast Neoplasms ,Postoperative Complications ,Treatment Outcome ,Risk Factors ,Germany ,Humans ,Female ,Surgery ,Factor Analysis, Statistical ,Perforator Flap ,Mastectomy ,Aged ,Retrospective Studies - Published
- 2021
13. The DIEP Flap as Well-established Method of Choice for Autologous Breast Reconstruction with a Low Complication Rate - Retrospective Single-centre 10-Year Experience
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K Staemmler, B Munder, Alina Abu-Ghazaleh, T Schulz, A Wolter, Olaf Fleischer, Christian Witzel, B Aufmesser, J Kornetka, Lukas Grüter, Mohammed Aldeeri, M Hagouan, P Stambera, S Fertsch, Christoph Andree, and Katrin Seidenstücker
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medicine.medical_specialty ,medicine.medical_treatment ,BRCA ,Gene mutation ,Mammakarzinom ,03 medical and health sciences ,0302 clinical medicine ,Breast cancer ,breast cancer ,DIEP flap ,Brustrekonstruktion ,Maternity and Midwifery ,medicine ,breast reconstruction ,GebFra Science ,breast ,030219 obstetrics & reproductive medicine ,business.industry ,Obstetrics and Gynecology ,Retrospective cohort study ,Prophylactic Mastectomy ,Original Article/Originalarbeit ,medicine.disease ,Surgery ,Radiation therapy ,DIEP-Lappen ,autologe Brustrekonstruktion ,Breast reconstruction ,business ,Mamma ,Mastectomy ,autologous breast reconstruction - Abstract
Background Breast cancer is the most common cancer affecting women in Germany. Despite breast-conserving therapy (BCT) being carried out in almost 70% of cases, a high number of women still require complete mastectomy. Prophylactic mastectomy is also indicated for women with a BRCA 1/2 gene mutation. In addition to implant-based heterologous breast reconstruction, autologous breast reconstruction using a DIEP flap has been found to be beneficial, particularly for patients who had prior radiotherapy. This study aims to show that DIEP flap reconstruction surgery is the method of choice for autologous breast reconstruction with a low rate of complications. Patients and Methods Autologous breast reconstruction using a DIEP flap was performed in 1124 patients between July 2004 and December 2014. Retrospective study criteria included potential risk factors such as age, BMI, smoking, chemotherapy and/or radiotherapy, and comorbidities as well as outcome parameters such as postoperative complications. Outcomes were evaluated with a mean follow-up of 24 months. Results A total of 1124 patients underwent 1274 free DIEP flap breast reconstructions, of which 150 were bilateral reconstructions. The primary indication was previous mastectomy in 785 cases, followed by prior implant-based reconstruction in 265 cases. The total flap loss rate was 0.6%. Postoperative surgical revision for abdominal wall hernia was required in 0.2% of cases. The group with a higher BMI and the group of smokers had significantly higher complication rates. Elderly patients (> 65 years), patients who had undergone chemo-/radiotherapy and patients with diabetes did not have higher complication rates. Conclusion DIEP flap surgery is an excellent option for autologous breast reconstruction, with a low rate of donor site morbidity and low complication rates. DIEP flap surgery carried out in a specialised interdisciplinary breast centre in a standardised clinical setting after prior careful patient selection to take account of risk factors such as high BMI and smoking is a reliable method with a low complication rate and satisfactory long-term reconstruction results.
- Published
- 2018
14. Electrical Nerve Stimulation Enhances Perilesional Branching after Nerve Grafting but Fails to Increase Regeneration Speed in a Murine Model
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Georgios Koulaxouzidis, Manfred Infanger, Christian Witzel, and Thomas M. Brushart
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0301 basic medicine ,Nerve stimulation ,Stimulation ,Synaptic Transmission ,03 medical and health sciences ,Mice ,0302 clinical medicine ,In vivo ,medicine ,Animals ,Axon ,Fibrin glue ,Nerve grafting ,business.industry ,Regeneration (biology) ,Anatomy ,medicine.disease ,Sciatic Nerve ,Axons ,Electric Stimulation ,Cell biology ,Nerve Regeneration ,Electrophysiology ,Mice, Inbred C57BL ,Luminescent Proteins ,030104 developmental biology ,medicine.anatomical_structure ,nervous system ,Models, Animal ,Crush injury ,Surgery ,business ,030217 neurology & neurosurgery - Abstract
Background Electrical stimulation immediately following nerve lesion helps regenerating axons cross the subsequently grafted nerve repair site. However, the results and the mechanisms remain open to debate. Some findings show that stimulation after crush injury increases axonal crossing of the repair site without affecting regeneration speed. Others show that stimulation after transection and fibrin glue repair doubles regeneration distance. Methods Using a sciatic-nerve-transection-graft in vivo model, we investigated the morphological behavior of regenerating axons around the repair site after unilateral nerve stimulation (20 Hz, 1 hour). With mice expressing axonal fluorescent proteins (thy1-YFP), we were able to calculate the following at 5 and 7 days: percentage of regenerating axons and arborizing axons, branches per axon, and regeneration distance and speed. Results Brief stimulation significantly increases the percentage of regenerating axons (5 days: 35.5 vs. 27.3% nonstimulated, p 0.05; 7 days: 43.3 vs. 33.9% nonstimulated, p 0.05), mainly by increasing arborizing axons (5 days: 49.3 [4.4] vs. 33.9 [4.1]% [p 0.001]; 7 days: 42.2 [5.6] vs. 33.2 [3.1]% [p 0.001]). Neither branches per arborizing axon nor regeneration speed were affected. Conclusion Our morphological data analysis revealed that electrical stimulation in this model increases axonal crossing of the repair site and promotes homogeneous perilesional branching, but does not affect regeneration speed.
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- 2016
15. In Situ Deactivation of Interleukin-6 Enhances Early Peripheral Nerve Regeneration in a Murine Injury Model
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Filip Simunovic, Joachim W. Fluhr, Gernot Reim, Georgios Koulaxouzidis, Christian Witzel, and G. Bjoern Stark
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Yellow fluorescent protein ,Mice ,In vivo ,medicine ,Animals ,Axon ,Receptor ,Nerve Transfer ,biology ,business.industry ,Interleukin-6 ,Regeneration (biology) ,Anatomy ,Nerve injury ,Molecular biology ,Sciatic Nerve ,Nerve Regeneration ,Mice, Inbred C57BL ,Disease Models, Animal ,medicine.anatomical_structure ,nervous system ,Microscopy, Fluorescence ,biology.protein ,Surgery ,Sciatic nerve ,medicine.symptom ,business - Abstract
Background Systemic alteration of interleukin-6 (IL-6) influences peripheral nerve regeneration. We investigated the potential influences of in situ (at the coaptation site) IL-6 modulation in a peripheral-nerve-transection/sciatic-nerve-graft in vivo model. Methods We quantified the elongation of regenerating axons, the number of arborizing axons, and the number of branches per arborizing axon 7 days after the injury in mice expressing axonal fluorescent proteins (thy-1-YFP mice). Sciatic nerves from nonexpressing mice (C57Bl6 or IL-6 −/− mice) were grafted into those expressing yellow fluorescent protein. We altered the in situ IL-6 concentration by loading a topical gelatin sponge with an inhibiting IL-6 receptor antibody or IL-6 combined with a soluble IL-6 receptor. Sciatic nerves from IL-6 −/− mice were grafted into an additional group. The contralateral sham-operated side served as control in all the groups. Results Axonal elongation increased significantly with the in situ application of the IL-6 receptor antibody, while topical IL-6 significantly reduced the regeneration distance. The number of arborizing axons increased significantly in nerves grafted from IL-6 −/− mice, whereas branches per arborizing axons remained stable. Conclusion In situ IL-6 receptor inhibition and IL-6 −/− nerve grafting enhance early peripheral nerve regeneration in an acute murine injury model.
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- 2015
16. DIEAP flap for safe definitive autologous breast reconstruction
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Carl Van Waes, Christian Witzel, B Munder, Christoph Andree, Katrin Seidenstuecker, Ajay L. Mahajan, Nathalie Roche, Karel E.Y. Claes, Phillip Blondeel, and Filip Stillaert
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Adult ,medicine.medical_specialty ,medicine.medical_treatment ,Mammaplasty ,Operative Time ,Free flap breast reconstruction ,Breast Neoplasms ,030230 surgery ,Abdominal wall ,03 medical and health sciences ,0302 clinical medicine ,Breast cancer ,Postoperative Complications ,Risk Factors ,medicine ,Humans ,Breast ,Prospective Studies ,Prospective cohort study ,Aged ,business.industry ,Abdominal Wall ,Smoking ,General Medicine ,Middle Aged ,medicine.disease ,Epigastric Arteries ,Surgery ,Radiation therapy ,medicine.anatomical_structure ,Treatment Outcome ,030220 oncology & carcinogenesis ,Abdomen ,Female ,business ,Breast reconstruction ,Perforator Flap ,Follow-Up Studies - Abstract
Background Breast cancer is the commonest form of cancer in women affecting almost a quarter of a million patients in the US annually. 30 percent of these patients and patients with genetic mutations undergo removal of the breast, as highlighted in a high profile celebrity patient. Although breast reconstruction with free microvascular transfer of a DIEAP flap from the abdomen is an ideal form of reconstruction, there have been misgivings about the complexity and potential complications. This study was aimed at clearing these misunderstandings and establishing the value of this form of breast reconstruction. Methods 1036 DIEAP flap breast reconstructions carried out at the University Hospital, Gent (five year period) and at the Sana Kliniken, Dusseldorf (three year period) were included prospectively. Comorbid factors like chemotherapy, radiotherapy, patient age >65 years, BMI >30 and smoking were recorded. Outcomes were evaluated over a mean follow up of 2 years. Results Overall complication rate related to the reconstructed breast and donor abdominal area was 6.8 percent. Total flap loss was seen in only 0.8 percent. The mean operating time was less than five hours. Older age, higher BMI, chemotherapy and radiotherapy did not have a significant influence on complication rates, however smoking resulted in significant delay in wound healing in the breast (p = 0.025) and abdominal wounds (p = 0.019). Conclusion The DIEAP flap is an excellent option for breast reconstruction, with a low level of donor site morbidity and complications. It is an autologous reconstruction that provides a stable long term result.
- Published
- 2015
17. Myosonographic study of abdominal wall dynamics to assess donor site morbidity after microsurgical breast reconstruction with a DIEP or an ms-2 TRAM flap
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K. Seidenstuecker, C. Andree, B. Munder, U. Legler, Christian Witzel, and A. Mahajan
- Subjects
Adult ,medicine.medical_specialty ,Microsurgery ,Mammaplasty ,Muscle Relaxation ,Rectus Abdominis ,030230 surgery ,Transplant Donor Site ,Transplantation, Autologous ,Body Mass Index ,Abdominal wall ,03 medical and health sciences ,0302 clinical medicine ,DIEP flap ,Patient age ,medicine ,Humans ,Prospective Studies ,Prospective cohort study ,Rectus abdominis muscle ,Ultrasonography ,business.industry ,Abdominal Wall ,Age Factors ,Middle Aged ,Surgery ,Tram flap ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Preoperative Period ,Tissue and Organ Harvesting ,Abdomen ,Female ,Breast reconstruction ,business ,Perforator Flap ,Muscle Contraction - Abstract
Currently, autologous breast reconstruction with a free tissue transfer from the lower abdomen is considered to be a safe method that provides a stable long-term solution. The DIEP-flap and the ms-2-TRAM-flap reconstructions have helped reduce donor site morbidity. In order to assess the potential differences between these techniques, we carried out myosonographic evaluations that assessed the muscle dynamics pre- and post-operatively. In addition to investigating the properties of the rectus abdominis muscle post-operatively, this prospective study also allowed us to analyse the muscle preoperatively and to investigate the prospects for harvesting a DIEP-flap as opposed to a TRAM-flap.Sixty patients underwent breast reconstruction with 71 (11 bilateral) free abdominal wall flaps (DIEP-: n = 48; ms-2-TRAM-flap: n = 23). Myosonographic examinations were performed preoperatively and at 3 and 6 months post-operatively. The thickness of the muscle at relaxation and maximum contraction and the difference between the muscle thickness measured at the two states were measured. A general-linear-model (GLM) was used for statistical analysis. The main variable was the surgical method, and the co-variables included BMI and patient age. The decision on whether to harvest a DIEP- or ms-2-TRAM-flap was made intra-operatively and based on the dominant perforator.It shows that the patients who underwent breast reconstruction with a DIEP-flap had significantly better muscle function (p 0.05) in the follow-up. In addition, the analysis revealed that better muscle function before surgery made it more likely that a patient would undergo a DIEP-flap-reconstruction successfully. Patient age also had a highly significant effect on muscle recovery (p 0.0005).This prospective study used a dynamic ultrasound evaluation of the abdominal wall and showed that the DIEP-flap significantly reduces donor site morbidity compared to the ms-2-TRAM-flap. The study also showed that good preoperative muscle function might increase the probability of surgeons performing a DIEP-flap reconstruction.
- Published
- 2015
18. Second intercostal internal mammary artery perforator (IMAP) fasciocutaneous flap as an alternative choice for the treatment of deep sternal wound infections (DSWI)
- Author
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Christian Witzel, Arzu Orhun, Georgios Koulaxouzidis, and Themistoklis Stavrakis
- Subjects
Male ,medicine.medical_specialty ,medicine.medical_treatment ,Risk Assessment ,Severity of Illness Index ,Cohort Studies ,Coronary artery bypass surgery ,Medicine ,Humans ,Surgical Wound Infection ,Mammary Arteries ,Aged ,Retrospective Studies ,Wound Healing ,Debridement ,business.industry ,Wound dehiscence ,Osteomyelitis ,Graft Survival ,Antibiotic Prophylaxis ,Middle Aged ,Plastic Surgery Procedures ,medicine.disease ,Prognosis ,Myocutaneous Flap ,Sternotomy ,Cardiac surgery ,Surgery ,Fasciocutaneous flap ,Treatment Outcome ,Mammary artery ,Female ,business ,Complication ,Perforator Flap - Abstract
Summary Sternal wound infections after sternotomy are associated with high morbidity, high mortality and escalating treatment costs. Repeated radical debridement – with the removal of any hardware – and wound conditioning are the prerequisites for reconstruction. Muscle and, less frequently, omentum flaps are usually used for reconstruction. However, these flaps are associated with considerable donor-site morbidity, long operation times and aesthetic impairment. Fasciocutaneous flaps seem to be an alternative. This study presents our experience of using the second intercostal mammary artery fasciocutaneous perforator flap for defect closure in nine patients (mean age: 70.2 years). Following a retrospective chart review, we assessed data on patient demographics, the type of cardiac surgery, the prevalence of deep sternal wound infection (DSWI) risk factors, identified pathogens, surgery duration, hospitalization tim patients had undergone coronary artery bypass surgery, and two had valve replacements. The mean duration of surgery (121.4 ± 39 min) was short. The patients had a mean body mass index (BMI) of 32.8 ± 4.9 kg/m 2 . An average flap size of 124 ± 22 cm 2 sufficiently covered and obliterated each defect. One mediastinal haematoma required revision surgery. One wound dehiscence at the flap and two at the donor site were managed conservatively. Our experience reveals that a fasciocutaneous flap based on the second intercostal perforator of the internal mammary artery can be an alternative, quick-to-prepare flap for covering sternal defects. In adipose patients, it has sufficient bulk, and it is large enough to cover common sternal wounds. It also has low complication and morbidity rates, and it achieves an aesthetically pleasing result.
- Published
- 2015
19. Fibrin glue repair leads to enhanced axonal elongation during early peripheral nerve regeneration in an in vivo mouse model
- Author
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Gernot Reim, Georgios Koulaxouzidis, and Christian Witzel
- Subjects
sciatic nerve ,macromolecular substances ,thy-1-YFP mice ,lcsh:RC346-429 ,Developmental Neuroscience ,In vivo ,Peripheral nerve ,branching ,Medicine ,Axon ,Fibrin glue ,nerve regeneration ,lcsh:Neurology. Diseases of the nervous system ,fibrin glue ,peripheral nerve regeneration ,arborisation ,neural regeneration ,Surgical repair ,business.industry ,Anatomy ,Repair site ,Transplantation ,medicine.anatomical_structure ,nervous system ,600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit::617 Chirurgie und verwandte medizinische Einrichtungen ,Sciatic nerve ,business ,Research Article - Abstract
Microsurgical suturing is the gold standard of nerve coaptation. Although literature on the usefulness of fibrin glue as an alternative is becoming increasingly available, it remains contradictory. Furthermore, no data exist on how both repair methods might influence the morphological aspects (arborization; branching) of early peripheral nerve regeneration. We used the sciatic nerve transplantation model in thy-1 yellow fluorescent protein mice (YFP; n = 10). Pieces of nerve (1cm) were grafted from YFP-negative mice (n = 10) into those expressing YFP. We performed microsuture coaptations on one side and used fibrin glue for repair on the contralateral side. Seven days after grafting, the regeneration distance, the percentage of regenerating and arborizing axons, the number of branches per axon, the coaptation failure rate, the gap size at the repair site and the time needed for surgical repair were all investigated. Fibrin glue repair resulted in regenerating axons travelling further into the distal nerve. It also increased the percentage of arborizing axons. No coaptation failure was detected. Gap sizes were comparable in both groups. Fibrin glue significantly reduced surgical repair time. The increase in regeneration distance, even after the short period of time, is in line with the results of others that showed faster axonal regeneration after fibrin glue repair. The increase in arborizing axons could be another explanation for better functional and electrophysiological results after fibrin glue repair. Fibrin glue nerve coaptation seems to be a promising alternative to microsuture repair.
- Published
- 2015
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20. In vivo stimulation of early peripheral axon regeneration by N-propionylmannosamine in the presence of polysialyltransferase ST8SIA2
- Author
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Christian Witzel, Georgios Koulaxouzidis, Herbert Hildebrandt, G. Björn Stark, and Werner Reutter
- Subjects
Nervous system ,Male ,Neurite ,Transplants ,Stimulation ,Mice, Transgenic ,Kaplan-Meier Estimate ,Biology ,chemistry.chemical_compound ,Bacterial Proteins ,In vivo ,medicine ,Animals ,Axon ,Biological Psychiatry ,Cell Size ,Polysialic acid ,Hexosamines ,Sciatic Nerve ,Axons ,Sialyltransferases ,Sialic acid ,Cell biology ,Nerve Regeneration ,Mice, Inbred C57BL ,Psychiatry and Mental health ,Disease Models, Animal ,Luminescent Proteins ,medicine.anatomical_structure ,Neuroprotective Agents ,Treatment Outcome ,nervous system ,Neurology ,chemistry ,Biochemistry ,Female ,Neurology (clinical) ,Sciatic nerve - Abstract
The key enzyme of sialic acid (Sia) biosynthesis is the bifunctional UDP-N-acetylglucosamine 2-epimerase/ManNAc kinase (GNE/MNK). It metabolizes the physiological precursor ManNAc and N-acyl modified analogues such as N-propionylmannosamine (ManNProp) to the respective modified sialic acid. Polysialic acid (polySia) is a crucial compound for several functions in the nervous system and is synthesized by the polysialyltransferases ST8SIA2 and ST8SIA4. PolySia can be modified in vitro and in vivo by metabolic glycoengineering of the N-acyl side chain of Sia. In vitro studies show that the application of ManNProp increases neurite outgrowth and accelerates the re-establishment of functional synapses. In this study, we investigate in vivo how ManNProp application might benefit peripheral nerve regeneration. In mice expressing axonal fluorescent proteins (thy-1-YFP), we transected the sciatic nerve and then replaced part of it with a sciatic nerve graft from non-expressing mice (wild-type mice or St8sia2 −/− mice). Analyses conducted 5 days after grafting showed that systemic application of ManNProp (200 mg/kg, twice a day, i.p.), but not of physiological ManNAc (1 g/kg, twice a day, i.p.), significantly increased the extent of axonal elongation, the number of arborizing axons and the number of branches per regenerating axon within the grafts from wild-type mice, but not in those from St8sia2 −/− mice. The results demonstrate that the application of ManNProp has beneficial effects on early peripheral nerve regeneration and indicate that the stimulation of axon growth depends on ST8SIA2 activity in the nerve graft.
- Published
- 2014
21. Pathway sampling by regenerating peripheral axons
- Author
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Christian Witzel, Charles A. Rohde, and Thomas M. Brushart
- Subjects
Wallerian degeneration ,Green Fluorescent Proteins ,Schwann cell ,Mice, Transgenic ,Biology ,Mice ,Dorsal root ganglion ,Pioneer axon ,Neural Pathways ,Neurites ,medicine ,Animals ,Axon ,Growth cone ,Motor Neurons ,General Neuroscience ,Nerve injury ,medicine.disease ,Sciatic Nerve ,Axons ,Nerve Regeneration ,medicine.anatomical_structure ,nervous system ,Sciatic nerve ,medicine.symptom ,Neuroscience - Abstract
A century ago, Ramon y Cajal described the generalized response of regenerating peripheral axons to their environment. By using mice that express fluorescent proteins in their axons, we are now able to quantify the response of individual axons to nerve transection and repair. Sciatic nerves from nonexpressing mice were grafted into those expressing a yellow variant of green fluorescent protein, then examined at 5, 7, or 10 days after repair. Regeneration was found to be a staggered process, with only 25% of axons crossing the repair in the first week. In the setting of Wallerian degeneration, this stagger will expose growth cones to an evolving menu of molecular cues upon which to base pathway decisions. Many axons arborize, allowing them to interact simultaneously with several pathways. Arborization could serve as the anatomical substrate for specificity generation through collateral pruning. Axons often travel laterally across the face of the distal stump before choosing a pathway. As a result, the average unbranched axon has access to over 100 distal Schwann cell tubes. This extensive access, however, does not ensure correct matching of axon and end organ, suggesting that pathway choice is made on the basis of factors other than end organ identity. These observations explain the failure of refined surgical techniques to restore normal function after nerve injury. The apparent wandering of axons across the repair defies surgical control and mandates a biological approach to reuniting severed axons with appropriate distal pathways.
- Published
- 2005
22. Electrical Stimulation Promotes Motoneuron Regeneration without Increasing Its Speed or Conditioning the Neuron
- Author
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Richard M. Royall, Paul N. Hoffman, Thomas M. Brushart, Beth B. Murinson, Christian Witzel, and Tessa Gordon
- Subjects
Nerve Crush ,Electric Stimulation Therapy ,Stimulation ,Time ,Rats, Sprague-Dawley ,Femoral nerve ,Suture (anatomy) ,medicine ,Animals ,ARTICLE ,Axon ,Ligation ,Motor Neurons ,business.industry ,General Neuroscience ,Regeneration (biology) ,Axotomy ,Sciatic Nerve ,Axons ,Nerve Regeneration ,Rats ,Anterograde tracing ,medicine.anatomical_structure ,nervous system ,Models, Animal ,Female ,Neuron ,business ,Neuroscience ,Femoral Nerve ,Reinnervation - Abstract
Motoneurons reinnervate the distal stump at variable rates after peripheral nerve transection and suture. In the rat femoral nerve model, reinnervation is already substantial 3 weeks after repair, but is not completed for an additional 7 weeks. However, this “staggered regeneration” can be temporally compressed by application of 20 Hz electrical stimulation to the nerve for 1 hr. The present experiments explore two possible mechanisms for this stimulation effect: (1) synchronization of distal stump reinnervation and (2) enhancement of regeneration speed. The first possibility was investigated by labeling all motoneurons that have crossed the repair at intervals from 4 d to 4 weeks after rat femoral nerve transection and suture. Although many axons did not cross until 3–4 weeks after routine repair, stimulation significantly increased the number crossing at 4 and 7 d, with only a few crossing after 2 weeks. Regeneration speed was studied by radioisotope labeling of transported proteins and by anterograde labeling of regenerating axons, and was not altered by stimulation. Attempts to condition the neuron by stimulating the femoral nerve 1 week before injury were also without effect. Electrical stimulation thus promotes the onset of motor axon regeneration without increasing its speed. This finding suggests a combined approach to improving the outcome of nerve repair, beginning with stimulation to recruit all motoneurons across the repair, followed by other treatments to speed and prolong axonal elongation.
- Published
- 2002
23. [Untitled]
- Author
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Wolfgang Rutsch, Adrian C. Borges, Matthias Witzel, Andrea Grohmann, Wolf S. Richter, Christian Witzel, Gert Baumann, Dieter L. Munz, Ingeborg Küchler, and Rona K. Reibis
- Subjects
medicine.medical_specialty ,Myocardial stunning ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Revascularization ,medicine.disease ,Dipyridamole ,Angioplasty ,Internal medicine ,medicine ,Cardiology ,Stress Echocardiography ,Dobutamine ,Myocardial infarction ,business ,Emission computed tomography ,medicine.drug - Abstract
Myocardial contrast echocardiography (MCE) is a promising diagnostic tool for detecting microvascular integrity. The aim of the study was to investigate the comparative specificity and sensitivity of intravenous MCE, technetium-99m Sestamibi single-photon emission computed tomography (SPECT) and dipyridamole–dobutamine (DIDO) stress echocardiography for predicting functional recovery after coronary revascularization in patients with acute myocardial infarction (AMI). Methods: In a prospective, observational study, 17 consecutive patients short after AMI who received successful treatment with primary percutaneous coronary angioplasty (PTCA) plus stent-implantation were examined with DIDO (dipyridamole with 0.28 mg/kg over 4 min plus dobutamine up to 10 mcg/kg/min), MCE (10 ml 4 g, 400 mg/ml Levovist® intravenously; second harmonic power imaging) within 12–24 h and resting perfusion SPECT within 48–72 h after PTCA. Functional recovery of regional contractile function after 6-month follow-up was the gold standard to assess viability. Results: The rate of agreement between SPECT and MCE was 69% and between SPECT and a positive response to stress echo was 76% for combined DIDO. MCE showed a higher sensitivity (96%) in the identification of viability than SPECT (77%) and combined DIDO alone (79%). Specificity was lower for viability recognition with MCE (58%) compared with SPECT (93%) and DIDO (87%). Conclusions: The wall motion response during DIDO echocardiography is useful in the prediction of recovery of regional and global ventricular function after revascularization in patients after AMI. Combined intravenous MCE and DIDO is more accurate in the diagnosis of stunned myocardium than Tc-99m-MIBI SPECT alone.
- Published
- 2002
24. Qualit�tsmanagement zur optimierten Steuerung des berufsgenossenschaftlichen Heilverfahrens f�r Handverletzungen
- Author
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Axel Ekkernkamp, Christian Witzel, Gerald Ziche, Helmut Last, and Andreas Eisenschenk
- Subjects
Public Health, Environmental and Occupational Health ,Emergency Medicine - Abstract
Die obere Extremitat stellt als funktionelle Einheit von Arm und Hand das wesentliche Instrument zur Ausfuhrung grobmotorischer und insbesondere feinmotorischer Leistungen dar. Die Hande sind die bedeutendsten Werkzeuge des Menschen und gehoren auch zu seinen wichtigsten Kommunikationsorganen. Der am haufigsten verletzte Korperteil ist die Hand mit angrenzendem Handgelenk. Eine sorgfaltige Behandlung von Handverletzungen ist insbesondere wegen der Erhaltung der Erwerbsfahigkeit von groser Bedeutung. In Zusammenarbeit mit dem Landesverband Berlin, Brandenburg, Mecklenburg-Vorpommern der gewerblichen Berufsgenossenschaften wurde ein Kontrollsystem etabliert, bei dem durch den jeweiligen gesetzlichen Unfallversicherungstrager (UV-Trager) alle handchirurgischen Falle gefiltert werden. Aus der Einstufung durch den UV-Trager ergibt sich, ob diese Vorgange im Unfallkrankenhaus Berlin vorgelegt werden sollen oder nicht. Hier wird dann entschieden, ob die begonnene Behandlung ausreichend ist oder durch weitere Interventionen erganzt werden soll. Die Zukunft wird zeigen, ob dieses Therapiekontrollsystem zu einer Senkung der komplizierten Verlaufe, zur Verkurzung der Behandlungszeiten und damit zur Kostenreduktion fuhrt.
- Published
- 2001
25. Skin-sparing mastectomy and immediate reconstruction with DIEP flap after breast-conserving therapy
- Author
-
Philipp Behrendt, Werner Audretsch, M Hagouan, Katrin Seidenstuecker, Christoph Andree, Tobias Köppe, B Munder, Philipp Richrath, Christian Witzel, and Carolin Nestle-Kraemling
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,Mammaplasty ,Free flap ,Mastectomy, Segmental ,Breast cancer ,breast cancer ,DIEP flap ,Clinical Research ,oncoplastic ,medicine ,Humans ,skin and connective tissue diseases ,Subcutaneous Mastectomy ,Skin ,integumentary system ,business.industry ,mastectomy ,General Medicine ,medicine.disease ,Surgery ,Plastic surgery ,Female ,Breast reconstruction ,business ,Organ Sparing Treatments ,Perforator Flap ,Mastectomy ,autologous breast reconstruction - Abstract
Summary Background Currently about 70% of women who suffer from breast cancer undergo breast-conserving therapy (BCT) without removing the entire breast. Thus, this surgical approach is the standard therapy for primary breast cancer. If corrections are necessary, the breast surgeon is faced with irritated skin and higher risks of complications in wound healing. After radiation, an implant-based reconstruction is only recommended in selected cases. Correction of a poor BCT outcome is often only solved with an additional extended operation using autologous reconstruction. Material/Methods In our plastic surgery unit, which focuses on breast reconstruction, we offer a skin-sparing or subcutaneous mastectomy, followed by primary breast reconstruction based on free autologous tissue transfer to correct poor BCT outcomes. Between July 2004 and May 2011 we performed 1068 deep inferior epigastric artery perforator (DIEP) flaps for breast reconstruction, including 64 skin-sparing or subcutaneous mastectomies, followed by primary DIEP breast reconstruction procedures after BCT procedures. Results In all free flap-based breast reconstruction procedures, we had a total flap loss in 0.8% (9 cases). Within the group of patients after BCT, we performed 41 DIEP flaps and 23 ms-2 TRAM flaps after skin-sparing or subcutaneous mastectomies to reconstruct the breast. Among this group we had of a total flap loss in 1.6% (1 case). Conclusions In cases of large tumour sizes and/or difficult tumour locations, the initial oncologic breast surgeon should inform the patients of a possibly poor cosmetic result after BCT and radiation. In our opinion a skin-sparing mastectomy with primary breast reconstruction should be discussed as a valid alternative.
- Published
- 2012
26. Volumenkontrolle des Behandlungsergebnis durch 3D Photodokumentation mittels Vectra 3D von Canfield nach Lipofilling der Brust
- Author
-
K Seidenstücker, P Richrath, Christian Witzel, B Munder, P Behrendt, C Andree, and M Hagouan
- Published
- 2012
27. Sind freie mikrochirurgische Lappenplastiken sicher für die autologe Brustrekonstruktion? Eine prospektive Studie über die mikrochirurgische Brustrekonstruktion als integrale Therapieoption im Brustzentrum Düsseldorf-Gerresheim bei über 1000 Patientinnen
- Author
-
Christian Witzel, C Andree, W Audretsch, T Köppe, P Behrendt, K Seidenstücker, B Munder, M Hagouan, P Richrath, and C Nestlé-Krämling
- Published
- 2012
28. Mikrochirurgische Brustrekonstruktion bei schlanken Patientinnen mit einem BMI ≤19
- Author
-
C Andree, B Munder, M Hagouan, P Behrendt, Christian Witzel, P Richrath, T Köppe, and K Seidenstücker
- Published
- 2011
29. Mikrochirurgische Brustrekonstruktion mit dem DIEP flap und Antiphospholipid-Syndrom: ein Case report
- Author
-
M Hagouan, B Munder, C Andree, P Richrath, T Köppe, K Seidenstücker, P Behrendt, and Christian Witzel
- Published
- 2011
30. Das Lipofilling als Formoptimierung nach Brustrekonstruktion durch Eigengewebe
- Author
-
Christian Witzel, C Andree, M Hagouan, K Seidenstücker, P Richrath, and B Munder
- Published
- 2011
31. Prophylaktische Skin sparing Mastektomie beim heriditären (BRCA1+2 Trägerinnen)/familiärem Mammakarzinom und Rekonstruktion durch Eigengewebe
- Author
-
C Andree, Christian Witzel, T Köppe, H Mazen, K Seidenstücker, P Richrath, B Munder, and P Behrendt
- Published
- 2010
32. Korrektur ästhetisch schlechter brusterhaltender Therapie (BET) Ergebnisse mit Rest-Skin Sparing Mastektomie und Sofortrekonstruktion durch DIEP oder fasziensparenden freien TRAM Lappen
- Author
-
C Andree, Christian Witzel, B Munder, P Richrath, T Köppe, K Seidenstücker, P Behrendt, and H Mazen
- Published
- 2010
33. Myocardial contrast echocardiography for predicting functional recovery after acute myocardial infarction
- Author
-
Adrian C, Borges, Wolf S, Richter, Christian, Witzel, Matthias, Witzel, Andrea, Grohmann, Rona K, Reibis, Wolfgang, Rutsch, Ingeborg, Küchler, Dieter L, Munz, and Gert, Baumann
- Subjects
Male ,Tomography, Emission-Computed, Single-Photon ,Echocardiography ,Predictive Value of Tests ,Image Processing, Computer-Assisted ,Myocardial Infarction ,Humans ,Female ,Middle Aged ,Echocardiography, Stress - Abstract
Myocardial contrast echocardiography (MCE) is a promising diagnostic tool for detecting microvascular integrity. The aim of the study was to investigate the comparative specificity and sensitivity of intravenous MCE, technetium-99m Sestamibi single-photon emission computed tomography (SPECT) and dipyridamole-dobutamine (DIDO) stress echocardiography for predicting functional recovery after coronary revascularization in patients with acute myocardial infarction (AMI).In a prospective, observational study, 17 consecutive patients short after AMI who received successful treatment with primary percutaneous coronary angioplasty (PTCA) plus stent-implantation were examined with DIDO (dipyridamole with 0.28 mg/kg over 4 min plus dobutamine up to 10 mcg/kg/min), MCE (10 ml 4 g, 400 mg/ml Levovist intravenously; second harmonic power imaging) within 12-24 h and resting perfusion SPECT within 48-72 h after PTCA. Functional recovery of regional contractile function after 6-month follow-up was the gold standard to assess viability.The rate of agreement between SPECT and MCE was 69% and between SPECT and a positive response to stress echo was 76% for combined DIDO. MCE showed a higher sensitivity (96%) in the identification of viability than SPECT (77%) and combined DIDO alone (79%). Specificity was lower for viability recognition with MCE (58%) compared with SPECT (93%) and DIDO (87%).The wall motion response during DIDO echocardiography is useful in the prediction of recovery of regional and global ventricular function after revascularization in patients after AMI. Combined intravenous MCE and DIDO is more accurate in the diagnosis of stunned myocardium than Tc-99m-MIBI SPECT alone.
- Published
- 2002
34. Combined dipyridamole and dobutamine echocardiography in myocardial hibernation: comparison with thallium uptake in patients after percutaneous transluminal coronary revascularization under circulatory support
- Author
-
Adrian C. Borges, Christian Witzel, Andrea Grohmann, Wolf Richter, Matthias Witzel, and Gert Baumann
- Subjects
Adult ,Male ,medicine.medical_specialty ,Cardiotonic Agents ,medicine.medical_treatment ,Vasodilator Agents ,Coronary Disease ,Scintigraphy ,Sensitivity and Specificity ,Coronary artery disease ,Internal medicine ,Angioplasty ,Dobutamine ,medicine ,Stress Echocardiography ,Humans ,Radiology, Nuclear Medicine and imaging ,Myocardial infarction ,Angioplasty, Balloon, Coronary ,Aged ,Myocardial Stunning ,Tomography, Emission-Computed, Single-Photon ,Ejection fraction ,medicine.diagnostic_test ,business.industry ,Dipyridamole ,Middle Aged ,medicine.disease ,Thallium Radioisotopes ,Cardiology ,Female ,Cardiology and Cardiovascular Medicine ,business ,medicine.drug ,Echocardiography, Stress ,Follow-Up Studies - Abstract
To investigate the specificity and sensitivity of the combination of dipyridamole and dobutamine echocardiography for predicting functional recovery in patients with reduced ventricular function after coronary angioplasty.Twenty-five patients, mean (SD) age 60.8 (10) years, with previous myocardial infarction (3 months), angiographically assessed coronary artery disease, and resting regional dysfunction (left ventricular ejection fraction35%) were studied. They underwent rest-redistribution thallium Tl-201 single photon emission computed tomography, and low-dose pharmacologic stress echocardiography with dobutamine (up to 10 microg/kg per minute), ultra low-dose dipyridamole (0.28 mg/kg over 4 minutes), and combined dipyridamole-dobutamine administration.The rate of agreement between Tl-201 and stress echo was 59% for dipyridamole, 62% for dobutamine, and 71% for combined dipyridamole-dobutamine (P.05 vs dipyridamole and vs dobutamine). Combined dipyridamole-dobutamine showed a higher sensitivity (89%) than Tl-201, dobutamine, or dipyridamole (84%, 78%, and 80%). Specificity was lower for functional recovery prediction with Tl-201 (60%) compared with dobutamine (89%), dipyridamole (90%), and combined dipyridamole-dobutamine (91%).Thallium is more sensitive than dipyridamole or dobutamine; the sensitivity gap is filled with combined dipyridamole-dobutamine. Pharmacologic stress echocardiography is more specific than Tl-201 scintigraphy.
- Published
- 2001
35. Electrical Stimulation Enhances Distal Reinnervation without Increasing Regeneration Speed
- Author
-
Christian Witzel, Thomas M. Brushart, Manfred Infanger, and G. Koulaxouzidis
- Subjects
medicine.medical_specialty ,medicine.anatomical_structure ,business.industry ,Anesthesia ,Regeneration (biology) ,Medicine ,Surgery ,Stimulation ,business ,Reinnervation - Published
- 2009
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