65 research outputs found
Nasal tip sutures: how to control shape and orientation in rhinoplasty
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
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
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
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
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
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
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
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
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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