909 resultados para surgical instrument


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The main objective of this research is to demonstrate that the Clean Development Mechanism (CDM), an instrument created under a global international treaty, can achieve multiple objectives beyond those for which it has been established. As such, while being already a powerful tool to contribute to the global fight against climate change, the CDM can also be successful if applied to different sectors not contemplated before. In particular, this research aimed at demonstrating that a wider utilization of the CDM in the tourism sector can represent an innovative way to foster sustainable tourism and generate additional benefits. The CDM was created by Article 12 of the Kyoto Protocol of the United Nations Framework Convention on Climate Change (UNFCCC) and represents an innovative tool to reduce greenhouse gases emissions through the implementation of mitigation activities in developing countries which generate certified emission reductions (CERs), each of them equivalent to one ton of CO2 not emitted in the atmosphere. These credits can be used for compliance reasons by industrialized countries in achieving their reduction targets. The logic path of this research begins with an analysis of the scientific evidences of climate change and its impacts on different economic sectors including tourism and it continues with a focus on the linkages between climate and the tourism sector. Then, it analyses the international responses to the issue of climate change and the peculiar activities in the international arena addressing climate change and the tourism sector. The concluding part of the work presents the objectives and achievements of the CDM and its links to the tourism sector by considering case studies of existing projects which demonstrate that the underlying question can be positively answered. New opportunities for the tourism sector are available.

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Flicker is a power quality phenomenon that applies to cycle instability of light intensity resulting from supply voltage fluctuation, which, in turn can be caused by disturbances introduced during power generation, transmission or distribution. The standard EN 61000-4-15 which has been recently adopted also by the IEEE as IEEE Standard 1453 relies on the analysis of the supply voltage which is processed according to a suitable model of the lamp – human eye – brain chain. As for the lamp, an incandescent 60 W, 230 V, 50 Hz source is assumed. As far as the human eye – brain model is concerned, it is represented by the so-called flicker curve. Such a curve was determined several years ago by statistically analyzing the results of tests where people were subjected to flicker with different combinations of magnitude and frequency. The limitations of this standard approach to flicker evaluation are essentially two. First, the provided index of annoyance Pst can be related to an actual tiredness of the human visual system only if such an incandescent lamp is used. Moreover, the implemented response to flicker is “subjective” given that it relies on the people answers about their feelings. In the last 15 years, many scientific contributions have tackled these issues by investigating the possibility to develop a novel model of the eye-brain response to flicker and overcome the strict dependence of the standard on the kind of the light source. In this light of fact, this thesis is aimed at presenting an important contribution for a new Flickermeter. An improved visual system model using a physiological parameter that is the mean value of the pupil diameter, has been presented, thus allowing to get a more “objective” representation of the response to flicker. The system used to both generate flicker and measure the pupil diameter has been illustrated along with all the results of several experiments performed on the volunteers. The intent has been to demonstrate that the measurement of that geometrical parameter can give reliable information about the feeling of the human visual system to light flicker.

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Articular cartilage lesions, with their inherent limited healing potential, are hard to treat and remain a challenging problem for orthopedic surgeons. Despite the development of several treatment strategies, the real potential of each procedure in terms of clinical benefit and effects on the joint degeneration processes is not clear. Aim of this PhD project was to evaluate the results, both in terms of clinical and imaging improvement, of new promising procedures developed to address the challenging cartilage pathology. Several studies have been followed in parallel and completed over the 3-year PhD, and are reported in detail in the following pages. In particular, the studies have been focused on the evaluation of the treatment indications of a scaffold based autologous chondrocyte implantation procedure, documenting its results for the classic indication of focal traumatic lesions, as well as its use for the treatment of more challenging patients, older, with degenerative lesions, or even as salvage procedure for more advanced stages of articular degeneration. The second field of study involved the analysis of the results obtained treating lesions of the articular surface with a new biomimetic osteochondral scaffold, which showed promise for the treatment of defects where the entire osteochondral unit is involved. Finally, a new minimally invasive procedure based on the use of growth factors derived from autologous platelets has been explored, showing results and underlining indicatios for the treatment of cartilage lesions and different stages of joint degeneration. These studies shed some light on the potential of the evaluated procedures, underlining good results as well as limits, they give some indications on the most appropriate candidates for their application, and document the current knowledge on cartilage treatment procedures suggesting the limitations that need to be addressed by future studies to improve the management of cartilage lesions.

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Introduction: Open fractures of the leg represent a severe trauma. The combined approach, shared between plastic and orthopaedic surgeons, is considered to be important, although this multidisciplinary treatment is not routinely performed. Aim of this study was to verify whether the orthoplastic treatment is of any advantage over the traditional simply orthopedic treatment, through a multicentric inclusion of these unfrequent injuries into a prospective study. Material and methods: The following trauma centres were involved: Rizzoli Orthopaedic Institute/University of Bologna (leading centre) and Maggiore Hospital (Bologna, Italy), Frenchay Hospital (Bristol, United Kingdom), Jinnah Hospital (Lahore, Pakistan). All patients consecutively hospitalized in the mentioned centres between January 2012 and December 2013 due to tibial open fractures were included in the study and prospectively followed up to December 2014. Demographics and other clinical features were recorded, including the type of treatment (orthopaedic or orthoplastic). The considered outcome measures included duration of hospitalization, time for bone union and soft tissue closure, Enneking score at 3, 6 and 12 months, the incidence of osteomyelitis and other complications. Results: A total of 164 patients were included in the study. Out of them 68% were treated with an orthoplastic approach, whereas 32% received a purely orthopedic treatment. All considered outcome measures showed to be improved by the orthoplastic approach, compared to the orthopaedic one: time for soft tissue closure (2 versus 25 weeks), duration of hospital stay (22 versus 55 days), time for bone union (6 versus 8.5 months) , number of additional operations (0.6 versus 1.2) and functional recovery of the limb at 12 months (27 versus 19, Enneking’s score). All results were statistically significant. Conclusion: The combined orthoplastic approach to the treatment of open tibia fractures, in particular for high grade injuries (Gustilo 3B), is proven to improve the outcome of these severe injuries.

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The goals of any treatment of cervical spine injuries are: return to maximum functional ability, minimum of residual pain, decrease of any neurological deficit, minimum of residual deformity and prevention of further disability. The advantages of surgical treatment are the ability to reach optimal reduction, immediate stability, direct decompression of the cord and the exiting roots, the need for only minimum external fixation, the possibility for early mobilisation and clearly decreased nursing problems. There are some reasons why those goals can be reached better by anterior surgery. Usually the bony compression of the cord and roots comes from the front therefore anterior decompression is usually the procedure of choice. Also, the anterior stabilisation with a plate is usually simpler than a posterior instrumentation. It needs to be stressed that closed reduction by traction can align the fractured spine and indirectly decompress the neural structures in about 70%. The necessary weight is 2.5 kg per level of injury. In the upper cervical spine, the odontoid fracture type 2 is an indication for anterior surgery by direct screw fixation. Joint C1/C2 dislocations or fractures or certain odontoid fractures can be treated with a fusion of the C1/C2 joint by anterior transarticular screw fixation. In the lower and middle cervical spine, anterior plating combined with iliac crest or fibular strut graft is the procedure of choice, however, a solid graft can also be replaced by filled solid or expandable vertebral cages. The complication of this surgery is low, when properly executed and anterior surgery may only be contra-indicated in case of a significant lesion or locked joints.

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This is a long-term outcome analysis of patients who underwent surgical treatment with a supraclavicular release for thoracic outlet syndrome (TOS).

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The objective of this study is to compare dental arch relationship following one-stage and three-stage surgical protocols of unilateral cleft lip and palate. Dental casts of 61 children (mean age, 11.2 years; SD, 1.7), consecutively treated in one center with one-stage closure of the complete cleft at 9.2 months (SD, 2.0), were compared with a sample of 97 patients (mean age, 8.7 years; SD, 0.9), consecutively treated with a three-stage protocol including delayed hard palate closure in another center. The dental casts were assigned random numbers to blind their origin. Four raters graded dental arch relationship and palatal morphology using the EUROCRAN index. The strength of agreement of rating was assessed with kappa statistics. Independent t tests were run to compare the EUROCRAN scores between one-stage and three-stage samples, and Fisher's exact tests were performed to evaluate differences of distribution of the EUROCRAN grades. The intra- and inter-rater agreement was moderate to very good. Dental arch relationship in the one-stage sample was less favorable than in three-stage group (mean scores, 2.58 and 1.97 for one-stage and three-stage samples, respectively; p?

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BACKGROUND: Peri-implantitis is common in patients with dental implants. We performed a single-blinded longitudinal randomized study to assess the effects of mechanical debridement on the peri-implant microbiota in peri-implantitis lesions. MATERIALS AND METHODS: An expanded checkerboard DNA-DNA hybridization assay encompassing 79 different microorganisms was used to study bacterial counts before and during 6 months following mechanical treatment of peri-implantitis in 17 cases treated with curettes and 14 cases treated with an ultrasonic device. Statistics included non-parametric tests and GLM multivariate analysis with p<0001 indicating significance and 80% power. RESULTS: At selected implant test sites, the most prevalent bacteria were: Fusobacterium nucleatum sp., Staphylococci sp., Aggregatibacter actinomycetemcomitans, Helicobacter pylori, and Tannerella forsythia. 30 min. after treatment with curettes, A. actinomycetemcomitans (serotype a), Lactobacillus acidophilus, Streptococcus anginosus, and Veillonella parvula were found at lower counts (p<0.001). No such differences were found for implants treated with the ultrasonic device. Inconsistent changes occurred following the first week. No microbiological differences between baseline and 6-month samples were found for any species or between treatment study methods in peri-implantitis. CONCLUSIONS: Both methods failed to eliminate or reduce bacterial counts in peri-implantitis. No group differences were found in the ability to reduce the microbiota in peri-implantitis.

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PURPOSE: The advent of imaging software programs has proved to be useful for diagnosis, treatment planning, and outcome measurement, but precision of 3-dimensional (3D) surgical simulation still needs to be tested. This study was conducted to determine whether the virtual surgery performed on 3D models constructed from cone-beam computed tomography (CBCT) can correctly simulate the actual surgical outcome and to validate the ability of this emerging technology to recreate the orthognathic surgery hard tissue movements in 3 translational and 3 rotational planes of space. MATERIALS AND METHODS: Construction of pre- and postsurgery 3D models from CBCTs of 14 patients who had combined maxillary advancement and mandibular setback surgery and 6 patients who had 1-piece maxillary advancement surgery was performed. The postsurgery and virtually simulated surgery 3D models were registered at the cranial base to quantify differences between simulated and actual surgery models. Hotelling t tests were used to assess the differences between simulated and actual surgical outcomes. RESULTS: For all anatomic regions of interest, there was no statistically significant difference between the simulated and the actual surgical models. The right lateral ramus was the only region that showed a statistically significant, but small difference when comparing 2- and 1-jaw surgeries. CONCLUSIONS: Virtual surgical methods were reliably reproduced. Oral surgery residents could benefit from virtual surgical training. Computer simulation has the potential to increase predictability in the operating room.

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Percutaneous nephrolithotomy (PCNL) for the treatment of renal stones and other related renal diseases has proved its efficacy and has stood the test of time compared with open surgical methods and extracorporal shock wave lithotripsy. However, access to the collecting system of the kidney is not easy because the available intra-operative image modalities only provide a two dimensional view of the surgical scenario. With this lack of visual information, several punctures are often necessary which, increases the risk of renal bleeding, splanchnic, vascular or pulmonary injury, or damage to the collecting system which sometimes makes the continuation of the procedure impossible. In order to address this problem, this paper proposes a workflow for introduction of a stereotactic needle guidance system for PCNL procedures. An analysis of the imposed clinical requirements, and a instrument guidance approach to provide the physician with a more intuitive planning and visual guidance to access the collecting system of the kidney are presented.