102 resultados para Reconstructive dosimetry
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Galactorrhea is a relatively common condition, but has rarely been seen following breast reduction surgery. To date there are only seven cases reported in the literature, all in premenopausal women. Postsurgical galactorrhea is a diagnosis of exclusion and differential diagnosis is extensive. Common causes should be excluded first. We present the case of a 56-year-old postmenopausal woman who underwent bilateral breast reduction and developed galactorrhea 2 months postoperatively. MRI scan of the skull as well as Thyroid-Stimulating Hormone (TSH), prolactin levels were normal. She was on long-term hormonal replacement therapy. Because of suspected nerve-related pain in her right breast she was commenced on amitriptyline. We hypothesise that galactorrhea may have been caused by underlying neuroma or irritation of the anterior branch of the T4 intercostal nerve or hormonal replacement therapy or a combination of both.
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The consequences of massive weight loss through bariatric procedures as well as diet are overall positive. However, the sequelae of massive weight loss present themselves as soft tissue redundancies in the areas of the lower abdomen, upper thigh, upper arm and breast as well as face and neck. This condition presents significant mechanical, physical and social day-to-day limitations for the quality of life of these patients. Surgical techniques are indicated for the reconstruction of the body shape and therapy of the above named problems and the coexistent psychosocial component. These surgical techniques involve dermolipectomies in different body areas and can lead to significant improvement. In view of the worldwide increase of adipositas and the increasing need for bariatric surgery, a parallel increase in demand for such reconstructive post-bariatric interventions can be foreseen. Early and precise information is crucial for the patients before engaging in weight reduction, as is the coverage of the costs of the resulting secondary reconstructive body contouring interventions by the insurance companies.
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What's known on the subject? and What does the study add? The EndoSew® prototype was first tested in a porcine model several years ago. The investigators found it both simple to master and reliable, its greatest advantage being a 2.4-fold time saving compared with straight laparoscopic suturing. In addition to that publication, there is a single case report describing the performance of an open EndoSew® suture to close parts (16 cm) of an ileal neobladder. The time for suturing the 16 cm ileum was 25 min, which is in line with our experience. The knowledge on this subject is limited to these two publications. We report on the first consecutive series of ileal conduits performed in humans using the novel prototype sewing device EndoSew®. The study shows that the beginning and the end of the suture process represent the critical procedural steps. It also shows that, overall, the prototype sewing machine has the potential to facilitate the intracorporeal suturing required in reconstructive urology for construction of urinary diversions. Objective To evaluate the feasibility and safety of the novel prototype sewing device EndoSew® in placing an extracorporeal resorbable running suture for ileal conduits. Patients and Methods We conducted a prospective single-centre pilot study of 10 consecutive patients undergoing ileal conduit, in whom the proximal end of the ileal conduit was closed extracorporeally using an EndoSew® running suture. The primary endpoint was the safety of the device and the feasibility of the sewing procedure which was defined as a complete watertight running suture line accomplished by EndoSew® only. Watertightness was assessed using methylene blue intraoperatively and by loopography on postoperative days 7 and 14. Secondary endpoints were the time requirements and complications ≤30 days after surgery. Results A complete EndoSew® running suture was feasible in nine patients; the suture had to be abandoned in one patient because of mechanical failure. In three patients, two additional single freehand stitches were needed to anchor the thread and to seal tiny leaks. Consequently, all suture lines in 6/10 patients were watertight with EndoSew® suturing alone and in 10/10 patients after additional freehand stitches. The median (range) sewing time was 5.5 (3–10) min and the median (range) suture length was 4.5 (2–5.5) cm. There were no suture-related complications. Conclusions The EndoSew® procedure is both feasible and safe. After additional freehand stitches in four patients all sutures were watertight. With further technical refinements, EndoSew® has the potential to facilitate the intracorporeal construction of urinary diversions.
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The analysis and reconstruction of forensically relevant events, such as traffic accidents, criminal assaults and homicides are based on external and internal morphological findings of the injured or deceased person. For this approach high-tech methods are gaining increasing importance in forensic investigations. The non-contact optical 3D digitising system GOM ATOS is applied as a suitable tool for whole body surface and wound documentation and analysis in order to identify injury-causing instruments and to reconstruct the course of event. In addition to the surface documentation, cross-sectional imaging methods deliver medical internal findings of the body. These 3D data are fused into a whole body model of the deceased. Additional to the findings of the bodies, the injury inflicting instruments and incident scene is documented in 3D. The 3D data of the incident scene, generated by 3D laser scanning and photogrammetry, is also included into the reconstruction. Two cases illustrate the methods. In the fist case a man was shot in his bedroom and the main question was, if the offender shot the man intentionally or accidentally, as he declared. In the second case a woman was hit by a car, driving backwards into a garage. It was unclear if the driver drove backwards once or twice, which would indicate that he willingly injured and killed the woman. With this work, we demonstrate how 3D documentation, data merging and animation enable to answer reconstructive questions regarding the dynamic development of patterned injuries, and how this leads to a real data based reconstruction of the course of event.
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Purpose: To investigate the dosimetric properties of an electronic portal imaging device (EPID) for electron beam detection and to evaluate its potential for quality assurance (QA) of modulated electron radiotherapy (MERT). Methods: A commercially available EPID was used to detect electron beams shaped by a photon multileaf collimator (MLC) at a source-surface distance of 70 cm. The fundamental dosimetric properties such as reproducibility, dose linearity, field size response, energy response, and saturation were investigated for electron beams. A new method to acquire the flood-field for the EPID calibration was tested. For validation purpose, profiles of open fields and various MLC fields (square and irregular) were measured with a diode in water and compared to the EPID measurements. Finally, in order to use the EPID for QA of MERT delivery, a method was developed to reconstruct EPID two-dimensional (2D) dose distributions in a water-equivalent depth of 1.5 cm. Comparisons were performed with film measurement for static and dynamic monoenergy fields as well as for multienergy fields composed by several segments of different electron energies. Results: The advantageous EPID dosimetric properties already known for photons as reproducibility, linearity with dose, and dose rate were found to be identical for electron detection. The flood-field calibration method was proven to be effective and the EPID was capable to accurately reproduce the dose measured in water at 1.0 cm depth for 6 MeV, 1.3 cm for 9 MeV, and 1.5 cm for 12, 15, and 18 MeV. The deviations between the output factors measured with EPID and in water at these depths were within ±1.2% for all the energies with a mean deviation of 0.1%. The average gamma pass rate (criteria: 1.5%, 1.5 mm) for profile comparison between EPID and measurements in water was better than 99% for all the energies considered in this study. When comparing the reconstructed EPID 2D dose distributions at 1.5 cm depth to film measurements, the gamma pass rate (criteria: 2%, 2 mm) was better than 97% for all the tested cases. Conclusions: This study demonstrates the high potential of the EPID for electron dosimetry, and in particular, confirms the possibility to use it as an efficient verification tool for MERT delivery.
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BACKGROUND Reconstruction of longitudinal defects of the lateral nasal alar might be challenging. Reconstruction with a bilobed flap is common for round defects normally the bilobed flap is less suited for longitudinal defects. OBJECTIVE We describe a birhombic flap for longitudinal defect. METHODS Demonstration of the technique and practical application for this kind of reconstruction. RESULTS The bilobed flap is a very useful flap for lateral nasal tip or distal alar reconstruction. We show that a small modification of the flap allows to cover also longitudinal defects on the lateral tip of the nose. As the first lobe movement corresponds more to the rhomboid transposition flap, we prefer to call it birhombic flap. CONCLUSION The birhombic flap has its place in reconstructive surgery. This flap has a specific indication and precise advantages to other repairs in particular to the bilobed flap.
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In recent years, implementation of 68Ga-radiometalated peptides for PET imaging of cancer has attracted the attention of clinicians. Herein, we propose the use of 44Sc (half-life = 3.97 h, average β+ energy [Eβ+av] = 632 keV) as a valuable alternative to 68Ga (half-life = 68 min, Eβ+av = 830 keV) for imaging and dosimetry before 177Lu-based radionuclide therapy. The aim of the study was the preclinical evaluation of a folate conjugate labeled with cyclotron-produced 44Sc and its in vitro and in vivo comparison with the 177Lu-labeled pendant. Methods: 44Sc was produced via the 44Ca(p,n)44Sc nuclear reaction at a cyclotron (17.6 ± 1.8 MeV, 50 μA, 30 min) using an enriched 44Ca target (10 mg 44CaCO3, 97.00%). Separation from the target material was performed by a semiautomated process using extraction chromatography and cation exchange chromatography. Radiolabeling of a DOTA-folate conjugate (cm09) was performed at 95°C within 10 min. The stability of 44Sc-cm09 was tested in human plasma. 44Sc-cm09 was investigated in vitro using folate receptor–positive KB tumor cells and in vivo by PET/CT imaging of tumor-bearing mice Results: Under the given irradiation conditions, 44Sc was obtained in a maximum yield of 350 MBq at high radionuclide purity (>99%). Semiautomated isolation of 44Sc from 44Ca targets allowed formulation of up to 300 MBq of 44Sc in a volume of 200–400 μL of ammonium acetate/HCl solution (1 M, pH 3.5–4.0) within 10 min. Radiolabeling of cm09 was achieved with a radiochemical yield of greater than 96% at a specific activity of 5.2 MBq/nmol. In vitro, 44Sc-cm09 was stable in human plasma over the whole time of investigation and showed folate receptor–specific binding to KB tumor cells. PET/CT images of mice injected with 44Sc-cm09 allowed excellent visualization of tumor xenografts. Comparison of cm09 labeled with 44Sc and 177Lu revealed almost identical pharmacokinetics. Conclusion: This study presents a high-yield production and efficient separation method of 44Sc at a quality suitable for radiolabeling of DOTA-functionalized biomolecules. An in vivo proof-of-concept study using a DOTA-folate conjugate demonstrated the excellent features of 44Sc for PET imaging. Thus, 44Sc is a valid alternative to 68Ga for imaging and dosimetry before 177Lu-radionuclide tumor therapy.
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The intensive use of nano-sized particles in many different applications necessitates studies on their risk assessment as there are still open questions on their safe handling and utilization. For reliable risk assessment, the interaction of nanoparticles (NP) with biological systems after various routes of exposure needs to be investigated using well-characterized NP. We report here on the generation of gold-NP (Au-NP) aerosols for inhalation studies with the spark ignition technique, and their characterization in terms of chemical composition, physical structure, morphology, and specific surface area, and on interaction with lung tissues and lung cells after 1 h inhalation by mice. The originally generated agglomerated Au-NP were converted into compact spherical Au-NP by thermal annealing at 600 °C, providing particles of similar mass, but different size and specific surface area. Since there are currently no translocation data available on inhaled Au-NP in the 10–50 nm diameter range, the emphasis was to generate NP as small as 20 nm for inhalation in rodents. For anticipated in vivo systemic translocation and dosimetry analyses, radiolabeled Au-NP were created by proton irradiating the gold electrodes of the spark generator, thus forming gamma ray emitting 195Au with 186 days half-life, allowing long-term biokinetic studies. The dissolution rate of 195Au from the NP was below detection limits. The highly concentrated, polydisperse Au-NP aerosol (1–2 × 107 NP/cm3) proved to be constant over several hours in terms of its count median mobility diameter, its geometric standard deviation and number concentration. After collection on filters particles can be re-suspended and used for instillation or ingestion studies.
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PURPOSE Glucagon-like peptide-1 receptor (GLP-1R) is a molecular target for imaging of pancreatic beta cells. We compared the ability of [Nle(14),Lys(40)(Ahx-NODAGA-(64)Cu)NH2]-exendin-4 ([(64)Cu]NODAGA-exendin-4) and [Nle(14),Lys(40)(Ahx-NODAGA-(68)Ga)NH2]-exendin-4 ([(68)Ga]NODAGA-exendin-4) to detect native pancreatic islets in rodents. PROCEDURES The stability, lipophilicity and affinity of the radiotracers to the GLP-1R were determined in vitro. The biodistribution of the tracers was assessed using autoradiography, ex vivo biodistribution and PET imaging. Estimates for human radiation dosimetry were calculated. RESULTS We found GLP-1R-specific labelling of pancreatic islets. However, the pancreas could not be visualised in PET images. The highest uptake of the tracers was observed in the kidneys. Effective dose estimates for [(64)Cu]NODAGA-exendin-4 and [(68)Ga]NODAGA-exendin-4 were 0.144 and 0.012 mSv/MBq, respectively. CONCLUSION [(64)Cu]NODAGA-exendin-4 might be more effective for labelling islets than [(68)Ga]NODAGA-exendin-4. This is probably due to the lower specific radioactivity of [(68)Ga]NODAGA-exendin-4 compared to [(64)Cu]NODAGA-exendin-4. The radiation dose in the kidneys may limit the use of [(64)Cu]NODAGA-exendin-4 as a clinical tracer.
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The prophylactic (risk-reducing) mastectomy is a world-wide recognized method for specifically treating the increased breast cancer risk in patients showing a BRCA1 and/or BRCA2 mutation as well as other patient groups at increased breast cancer risk. This option should be offered to all patients having the pertinent risk profile. Breast reconstruction is an integral part of the risk-reducing mastectomy procedure and all possible methods of breast reconstruction, especially autologous tissue reconstruction should be offered to all patients having a medical indication and desiring this surgical treatment. These patients are best managed in certified Breast Care Centres where the different medical and surgical specialists can address interdisciplinary all aspects of genetic counselling, preoperative counselling, mastectomy and reconstructive techniques as well as the necessary postoperative surveillance.
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BACKGROUND AND PURPOSE Intensity-modulated radiotherapy (IMRT) credentialing for a EORTC study was performed using an anthropomorphic head phantom from the Radiological Physics Center (RPC; RPC(PH)). Institutions were retrospectively requested to irradiate their institutional phantom (INST(PH)) using the same treatment plan in the framework of a Virtual Phantom Project (VPP) for IMRT credentialing. MATERIALS AND METHODS CT data set of the institutional phantom and measured 2D dose matrices were requested from centers and sent to a dedicated secure EORTC uploader. Data from the RPC(PH) and INST(PH) were thereafter centrally analyzed and inter-compared by the QA team using commercially available software (RIT; ver.5.2; Colorado Springs, USA). RESULTS Eighteen institutions participated to the VPP. The measurements of 6 (33%) institutions could not be analyzed centrally. All other centers passed both the VPP and the RPC ±7%/4 mm credentialing criteria. At the 5%/5 mm gamma criteria (90% of pixels passing), 11(92%) as compared to 12 (100%) centers pass the credentialing process with RPC(PH) and INST(PH) (p = 0.29), respectively. The corresponding pass rate for the 3%/3 mm gamma criteria (90% of pixels passing) was 2 (17%) and 9 (75%; p = 0.01), respectively. CONCLUSIONS IMRT dosimetry gamma evaluations in a single plane for a H&N prospective trial using the INST(PH) measurements showed agreement at the gamma index criteria of ±5%/5 mm (90% of pixels passing) for a small number of VPP measurements. Using more stringent, criteria, the RPC(PH) and INST(PH) comparison showed disagreement. More data is warranted and urgently required within the framework of prospective studies.
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PURPOSE To assess the usefulness of cone beam CT (CBCT) for dacryocystography (DCG) using either direct syringing or passive application of contrast medium. METHODS Ten consecutive patients with epiphora who had CBCT-DCG in a sitting position were retrospectively analyzed. CBCT-DCGs were performed using 2 techniques: direct syringing with contrast medium or using the passive technique, where patients received 3 drops of contrast medium into the conjunctival sac before CBCT-DCG. Clinical and radiologic diagnoses were compared for both groups. RESULTS The 10 patients (men = 3) had a mean age of 63.2 years. Both techniques proved to be simple procedures with good delineation of the bone, soft tissue, and the contrast medium in the lacrimal system. No side effects were noted. CONCLUSIONS CBCT-DCG is a useful alternative to determine the localization of stenosis in patients with chronic epiphora.
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OBJECTIVE To systematically analyze the regenerative effect of the available biomaterials either alone or in various combinations for the treatment of periodontal intrabony defects as evaluated in preclinical histologic studies. DATA SOURCES A protocol covered all aspects of the systematic review methodology. A literature search was performed in Medline, including hand searching. Combinations of searching terms and several criteria were applied for study identification, selection, and inclusion. The preliminary outcome variable was periodontal regeneration after reconstructive surgery obtained with the various regenerative materials, as demonstrated through histologic/ histomorphometric analysis. New periodontal ligament, new cementum, and new bone formation as a linear measurement in mm or as a percentage of the instrumented root length were recorded. Data were extracted based on the general characteristics, study characteristics, methodologic characteristics, and conclusions. Study selection was limited to preclinical studies involving histologic analysis, evaluating the use of potential regenerative materials (ie, barrier membranes, grafting materials, or growth factors/proteins) for the treatment of periodontal intrabony defects. Any type of biomaterial alone or in various combinations was considered. All studies reporting histologic outcome measures with a healing period of at least 6 weeks were included. A meta-analysis was not possible due to the heterogeneity of the data. CONCLUSION Flap surgery in conjunction with most of the evaluated biomaterials used either alone or in various combinations has been shown to promote periodontal regeneration to a greater extent than control therapy (flap surgery without biomaterials). Among the used biomaterials, autografts revealed the most favorable outcomes, whereas the use of most biologic factors showed inferior results compared to flap surgery.
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Advertisement for any dental treatment was rare in Switzerland. Then the use of digital media became popular, particularly in the field of implant- and esthetic-dentistry. In parallel to the dental schools of public universities, private universities and companies built up centers for continuing education that issue specialists diplomas and M.Sc. degrees. Prosthodontics itself is characterized by many sub-disciplines that incorporated their own associations. These also offer graduate training curricula which diminish the significance of specialization in prosthodontics. Specialized prosthodontists do not have a financial benefit in Switzerland where dentistry is not supported by any insurance. In other European countries funding of prosthodontic treatment depends on their healthcare systems. There are four specialties in Dentistry recognized by the European Union (EU). Specialization in prosthodontics was introduced in Sweden already in 1982 and today it is declared in about 20 European countries, while for others no recognized program exists. Thus there are great variations with more recognized specialists in former east European countries. In Switzerland the prosthodontic specialization curriculum was developed and guided by the Swiss Society for Reconstructive Dentistry, and only in 2001 it became fully acknowledged by the Federal Department of Health. The four Swiss Universities offer the 3-year program under the supervision of the society, while the government remains the executive body. In 2003 EPA tried to set up guidelines and quality standards for an EPA recognized specialization. In spite of these attempts and the Bologna Reform in Europe, it appears that the quality standards and the level of education still may differ significantly among European countries.