65 research outputs found

    Nasal tip sutures: how to control shape and orientation in rhinoplasty

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    Nasal tip surgery is universally recognized as the most challenging part of the rhinoplasty procedure. "The tip makes the nose”. Narrowing the anatomically complex alar cartilages can lead to functional and aesthetic unfavourable outcomes. A thorough understanding of the ideal surface aesthetics and contours and spatial relationships of the structures of the nose tip is mandatory. In primary rhinoplasty, a very large percentage of visible tip deformities involve two major areas: the domes and the lateral crura. Suture techniques have the potential to modify the position, shape and definition of the tip. However, even sutures may result in changes beyond the main goals for which they are placed. The final suture effects are influenced by factors such as forces intrinsic to the cartilages, the degree of suture tightening, and limitations posed by the soft-tissue attachments. The closed delivery approach is our favourite. In a step-by-step fashion, first the medial pillar of the tripod should be addressed, establishing stable and strong tip support and basic dome projection symmetry. Subsequently and in our experience, in a standard procedure shaping lateral crura and domes, using reversible techniques that preserve structural integrity of the rimstrip, would be advisable. One of the main goals is not only to narrow the tip but to change the angle of rotation of the lateral crus surface in relation to the sagittal upper septal margin. Once marked the new dome defining point, with a variable combination of the lateral crural steal technique, sutures such as cranial tip sutures (CTS) and hemitransdomal sutures (HTS) might produce the needed outcome of everting and rotating the caudal margin of the lateral crura above the cranial edge. These sutures can gradually increase domal convexity and reduce lateral crura convexity. Additional dome equalization suture can guarantee more symmetry and then one or more lateral crural spanning sutures help in achieving supplementary eversion of the lateral crus. After establishing adequate projection, the tip rotation or position sutures are placed between the cranial edge of intermediate crura and the dorsal septum. The personal association of suture techniques is presented in this study and the long-term subjective and objective results are discussed along with the pros and cons

    The challenging Silent sinus syndrome

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    The Silent sinus syndrome (SSS), first described in 1964 by Montgomery, is considered a relatively rare pathological entity, but it is presumably underdiagnosed and underreported. Terms such as imploding antrum and chronic maxillary atelectasis (CMA) have interchangeably been used to describe this syndrome, even though CMA has been postulated to represent either a different entity or a stage of evolution of the same disease. Bilateral involvement has been documented in a limited number of cases. Silent ethmoid sinus and silent frontal sinus syndromes have been described. The prevalent initial presentation is facial asymmetry with progressive “silent” painless unilateral enophthalmos and hypoglobus, and rarely diplopia. Isolated maxillary sinus hypoplasia must be differentiated. The etiopathogenesis is poorly understood and still under debate. According to the diagnostic criteria, SSS should spontaneously develops in absence of previous trauma or surgery. Secondary SSS to trauma or surgery, or to other causes like inflammation or tumor, has been documented in literature. The diagnosis relies on the CT, which typically shows unilateral hypoplastic and opacified maxillary sinus with inward bowing and remodeling of the sinus walls and inferior displacement of the orbital floor, an enlarged retroantral fat pad, a lateralized uncinate process, and a blocked ostiomeatal complex. The treatment of SSS aims at restoring the eye position and orbital floor height, to prevent progression of enophthalmos, to restore ventilation and drainage of the sinus. These objectives are achieved in single or two-stage surgery. The timing for management of the orbital floor is still under debate.The universally accepted treatment is surgical and usually accomplished by endoscopic sinus surgery. Associated middle turbinate hypertrophy and septal deviation must be previously addressed. Precise and gentle endoscopic removal of the obstruction of the ethmoid infundibulum, simply performing an inferior posteroanterior uncinectomy, since the uncinate process has constantly been found atelectatic and adherent to the lateral nasal wall, can reestablish the patency of the natural maxillary ostium. In our experience, following middle meatal antrostomy, long-term observation with staged orbital surgery, if required, is recommended. In this study, we present our cases with a focus on surgical stratagems developed in order to reduce the risk of injuring the orbit and to achieve long-lasting results

    Nasal tip sutures: how to control shape and orientation in rhinoplasty

    Get PDF
    Nasal tip surgery is universally recognized as the most challenging part of the rhinoplasty procedure. "The tip makes the nose”. Narrowing the anatomically complex alar cartilages can lead to functional and aesthetic unfavourable outcomes. A thorough understanding of the ideal surface aesthetics and contours and spatial relationships of the structures of the nose tip is mandatory. In primary rhinoplasty, a very large percentage of visible tip deformities involve two major areas: the domes and the lateral crura. Suture techniques have the potential to modify the position, shape and definition of the tip. However, even sutures may result in changes beyond the main goals for which they are placed. The final suture effects are influenced by factors such as forces intrinsic to the cartilages, the degree of suture tightening, and limitations posed by the soft-tissue attachments. The closed delivery approach is our favourite. In a step-by-step fashion, first the medial pillar of the tripod should be addressed, establishing stable and strong tip support and basic dome projection symmetry. Subsequently and in our experience, in a standard procedure shaping lateral crura and domes, using reversible techniques that preserve structural integrity of the rimstrip, would be advisable. One of the main goals is not only to narrow the tip but to change the angle of rotation of the lateral crus surface in relation to the sagittal upper septal margin. Once marked the new dome defining point, with a variable combination of the lateral crural steal technique, sutures such as cranial tip sutures (CTS) and hemitransdomal sutures (HTS) might produce the needed outcome of everting and rotating the caudal margin of the lateral crura above the cranial edge. These sutures can gradually increase domal convexity and reduce lateral crura convexity. Additional dome equalization suture can guarantee more symmetry and then one or more lateral crural spanning sutures help in achieving supplementary eversion of the lateral crus. After establishing adequate projection, the tip rotation or position sutures are placed between the cranial edge of intermediate crura and the dorsal septum. The personal association of suture techniques is presented in this study and the long-term subjective and objective results are discussed along with the pros and cons

    The challenging Silent sinus syndrome

    Get PDF
    The Silent sinus syndrome (SSS), first described in 1964 by Montgomery, is considered a relatively rare pathological entity, but it is presumably underdiagnosed and underreported. Terms such as imploding antrum and chronic maxillary atelectasis (CMA) have interchangeably been used to describe this syndrome, even though CMA has been postulated to represent either a different entity or a stage of evolution of the same disease. Bilateral involvement has been documented in a limited number of cases. Silent ethmoid sinus and silent frontal sinus syndromes have been described. The prevalent initial presentation is facial asymmetry with progressive “silent” painless unilateral enophthalmos and hypoglobus, and rarely diplopia. Isolated maxillary sinus hypoplasia must be differentiated. The etiopathogenesis is poorly understood and still under debate. According to the diagnostic criteria, SSS should spontaneously develops in absence of previous trauma or surgery. Secondary SSS to trauma or surgery, or to other causes like inflammation or tumor, has been documented in literature. The diagnosis relies on the CT, which typically shows unilateral hypoplastic and opacified maxillary sinus with inward bowing and remodeling of the sinus walls and inferior displacement of the orbital floor, an enlarged retroantral fat pad, a lateralized uncinate process, and a blocked ostiomeatal complex. The treatment of SSS aims at restoring the eye position and orbital floor height, to prevent progression of enophthalmos, to restore ventilation and drainage of the sinus. These objectives are achieved in single or two-stage surgery. The timing for management of the orbital floor is still under debate.The universally accepted treatment is surgical and usually accomplished by endoscopic sinus surgery. Associated middle turbinate hypertrophy and septal deviation must be previously addressed. Precise and gentle endoscopic removal of the obstruction of the ethmoid infundibulum, simply performing an inferior posteroanterior uncinectomy, since the uncinate process has constantly been found atelectatic and adherent to the lateral nasal wall, can reestablish the patency of the natural maxillary ostium. In our experience, following middle meatal antrostomy, long-term observation with staged orbital surgery, if required, is recommended. In this study, we present our cases with a focus on surgical stratagems developed in order to reduce the risk of injuring the orbit and to achieve long-lasting results

    Development and validation of a dissolution method using HPLC for diclofenac potassium in oral suspension

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    The present study describes the development and validation of an in vitro dissolution method for evaluation to release diclofenac potassium in oral suspension. The dissolution test was developed and validated according to international guidelines. Parameters like linearity, specificity, precision and accuracy were evaluated, as well as the influence of rotation speed and surfactant concentration on the medium. After selecting the best conditions, the method was validated using apparatus 2 (paddle), 50-rpm rotation speed, 900 mL of water with 0.3% sodium lauryl sulfate (SLS) as dissolution medium at 37.0 ± 0.5°C. Samples were analyzed using the HPLC-UV (PDA) method. The results obtained were satisfactory for the parameters evaluated. The method developed may be useful in routine quality control for pharmaceutical industries that produce oral suspensions containing diclofenac potassium

    Urban Disaster-Prevention Strategies Using Macroseismic Fields and Fault Sources

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    This contribution presents the general framework of the European project UPStrat-MAFA "Urban disaster Prevention Strategies using MAcroseismic Fields and FAult Sources" and its ongoing activities. A unique probabilistic procedure is being used for seismic hazard evaluation, using both macroseismic fields and characteristics of fault sources for the analysis of data from volcanic and tectonic areas: Mt. Etna, Mt. Vesuvius and Campi Flegrei (Italy), Azores Islands (Portugal), South Iceland (Iceland), Alicante-Murcia (Spain), and mainland and offshore Portugal. An improvement of urban scale vulnerability information on building and network systems (typologies, schools, strategic buildings, lifelines, and others) is proposed in the form of a global Disruption Index, with the objective to provide a systematic way of measuring earthquake impact in urbanized areas considered as complex networks. Disaster prevention strategies are considered based on an education information system, another effective component of the disaster risk reduction given by long-term activities.Co-financed by the EU - Civil Protection Financial Instrument, in the framework the European project ”Urban disaster Prevention Strategies using MAcroseismic Fields and FAult Sources (Acronym: UPStrat-MAFA, Grant Agreement N. 23031/2011/613486/SUB/A5). http://ec.europa.eu/echo/funding/cp_projects2011_en.htmPublishedLisbon - Portugal4.1. Metodologie sismologiche per l'ingegneria sismicaope

    Urban Disaster-Prevention Strategies Using Macroseismic Fields and Fault Sources

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    This contribution presents the general framework of the European project UPStrat-MAFA "Urban disaster Prevention Strategies using MAcroseismic Fields and FAult Sources" and its ongoing activities. A unique probabilistic procedure is being used for seismic hazard evaluation, using both macroseismic fields and characteristics of fault sources for the analysis of data from volcanic and tectonic areas: Mt. Etna, Mt. Vesuvius and Campi Flegrei (Italy), Azores Islands (Portugal), South Iceland (Iceland), Alicante-Murcia (Spain), and mainland and offshore Portugal. An improvement of urban scale vulnerability information on building and network systems (typologies, schools, strategic buildings, lifelines, and others) is proposed in the form of a global Disruption Index, with the objective to provide a systematic way of measuring earthquake impact in urbanized areas considered as complex networks. Disaster prevention strategies are considered based on an education information system, another effective component of the disaster risk reduction given by long-term activities

    Earthquake rupture forecasts for the mps19 seismic hazard model of Italy

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    In recent years, new approaches for developing earthquake rupture forecasts (ERFs) have been proposed to be used as an input for probabilistic seismic hazard assessment (PSHA). Zone-based approaches with seismicity rates derived from earthquake catalogs are commonly used in many countries as the standard for national seismic hazard models. In Italy, a single zone-based ERF is currently the basis for the official seismic hazard model. In this contribution, we present eleven new ERFs, including five zone-based, two smoothed seismicity-based, two fault-based, and two geodetic-based, used for a new PSH model in Italy. The ERFs were tested against observed seismicity and were subject to an elicitation procedure by a panel of PSHA experts to verify the scientific robustness and consistency of the forecasts with respect to the observations. Tests and elicitation were finalized to weight the ERFs. The results show a good response to the new inputs to observed seismicity in the last few centuries. The entire approach was a first attempt to build a community-based set of ERFs for an Italian PSHA model. The project involved a large number of seismic hazard practitioners, with their knowledge and experience, and the development of different models to capture and explore a large range of epistemic uncertainties in building ERFs, and represents an important step forward for the new national seismic hazard model

    Validation of high performance liquid chromatography method for determination of meloxicam loaded PEGylated nanocapsules

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    abstract A method to ensure that an analytical method will produce reliable and interpretable information about the sample must first be validated, making sure that the results can be trusted and traced. In this study, we propose to validate an analytical high performance liquid chromatography (HPLC) method for the quantitation of meloxicam loaded PEGylated nanocapsules(M-PEGNC). We performed a validation study, evaluated parameters including specificity, linearity, quantification limit, detection limit, accuracy, precision and robustness. PEGylated nanocapsules were prepared by interfacial deposition of preformed polymer, and the particle size, polydispersity index, zeta potential, pH value and encapsulation efficiency were characterized. The proposed HPLC method provides selective, linear results in the range of 1.0-40.0 μg/mL; quantification and detection limits were 1.78 μg/mL and 0.59 μg/mL, respectively; relative standard deviation for repeatability was 1.35% and intermediate precision was 0.41% and 0.61% for analyst 1 and analyst 2, respectively; accuracy between 99.23 and 101.79%; robustness between 97.13 and 98.45% for the quantification of M-PEGNC. Mean particle diameters were 261 ± 13 nm and 249 ± 20 nm, polydispersity index was 0.15 ± 0.07 and 0.17 ± 0.06, pH values were 5.0 ± 0.2 and 5.2 ± 0.1, and zeta-potential values were -37.9 ± 3.2 mV e -31.8 ± 2.8 mV for M-PEGNC and placebo(B-PEGNC), respectively. In conclusion, the proposed analytical method is suitable for the quality control of M-PEGNC. Moreover, suspensions showed monomodal size distributions and low polydispersity index indicating high homogeneity of formulations with narrow size distributions, and appropriate pH and zeta potential. The extraction process was efficient for release of meloxicam from nanostructured systems
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