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1.
Biomaterials ; 206: 41-48, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30925287

RESUMO

Stress urinary incontinence (SUI) is a life changing condition, affecting 20 million women worldwide. In this study, we developed a bioactive, injectable bulking agent that consists of Permacol™ (Medtronic, Switzerland) and recombinant insulin like growth factor-1 conjugated fibrin micro-beads (fib_rIGF-1) for its bulk stability and capacity to induce muscle regeneration. Therefore, Permacol™ formulations were injected in the submucosal space of rabbit bladders. The ability of a bulking material to form a stable and muscle-inducing bulk represents for us a promising therapeutic approach to achieve a long-lasting treatment for SUI. The fib_rIGF-1 showed no adverse effect on human smooth muscle cell metabolic activity and viability in vitro based on AlamarBlue assays and Live/Dead staining. Three months after injection of fib_rIGF-1 together with Permacol™ into the rabbit bladder wall, we observed a smooth muscle tissue like formation within the injected materials. Positive staining for alpha smooth muscle actin, calponin, and caldesmon demonstrated a contractile phenotype of the newly formed smooth muscle tissue. Moreover, the fib_rIGF-1 treated group also improved the neovascularization at the injection site, confirmed by CD31 positive staining compared to bulks made of PermacolTM only. The results of this study encourage us to further develop this injectable, bioactive bulking material towards a future therapeutic approach for a minimal invasive and long-lasting treatment of SUI.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Incontinência Urinária por Estresse/terapia , Animais , Materiais Biocompatíveis/química , Feminino , Fibrina/química , Humanos , Imuno-Histoquímica , Camundongos , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Coelhos , Incontinência Urinária por Estresse/metabolismo , Sistema Urinário/citologia , Sistema Urinário/metabolismo
2.
Bone Joint J ; 99-B(12): 1651-1657, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29212689

RESUMO

AIMS: The aim of this study was to report a retrospective, consecutive series of patients with adolescent idiopathic scoliosis (AIS) who were treated with posterior minimally invasive surgery (MIS) with a mean follow-up of two years (sd 1.4; 0.9 to 0 3.7). Our objectives were to measure the correction of the deformity and record the peri-operative morbidity. Special attention was paid to the operating time (ORT), estimated blood loss (EBL), length of stay (LOS) and further complications. PATIENTS AND METHODS: We prospectively collected the data of 70 consecutive patients with AIS treated with MIS using three incisions and a muscle-splitting approach by a single surgeon between June 2013 and February 2016 and these were retrospectively reviewed. There were eight male and 62 female patients with a mean age of 15 years (sd 4.5 ) with a mean body mass index of 19.8 kg/m2 (sd 5.4). The curves were classified according to Lenke; 40 curves were type 1, 15 were type 2, three were type 3, two were type 4, eight were type 5 and two were type 6. RESULTS: The mean primary Cobb angle was corrected from 58.9° (sd 12.6°) pre-operatively to 17.7° (sd 10.2°) post-operatively with a mean correction of 69% (sd 20%, p < 0.001). The mean kyphosis at T5 to T12 increased from 24.2° (sd 12.2°) pre-operatively to 30.1° (sd 9.6°, p < 0.001) post-operatively. Peri-operative (30 days) complications occurred in three patients(4.2%): one subcutaneous haematoma, one deep venous thrombosis and one pulmonary complication. Five additional complications occurred in five patients (7.1%): one superficial wound infection, one suture granuloma and three delayed deep surgical site infections. The mean ORT was 337.1 mins (sd 121.3); the mean EBL was 345.7 ml (sd 175.1) and the mean LOS was 4.6 days (sd 0.8). CONCLUSION: The use of MIS for patients with AIS results in a significant correction of spinal deformity in both the frontal and sagittal planes, with a low EBL and a short LOS. The rate of peri-operative complications compares well with that following a routine open technique. The longer term safety and benefit of MIS in these patients needs to be evaluated with further follow-up of a larger cohort of patients. Cite this article: Bone Joint J 2017;99-B:1651-7.


Assuntos
Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Fusão Vertebral/métodos , Adolescente , Perda Sanguínea Cirúrgica , Criança , Feminino , Humanos , Tempo de Internação , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Morbidade , Período Perioperatório , Estudos Retrospectivos , Fusão Vertebral/efeitos adversos , Resultado do Tratamento , Adulto Jovem
3.
Gait Posture ; 39(1): 436-42, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24044970

RESUMO

A child's natural gait pattern may be affected by the gait laboratory environment. Wearable devices using body-worn sensors have been developed for gait analysis. The purpose of this study was to validate and explore the use of foot-worn inertial sensors for the measurement of selected spatio-temporal parameters, based on the 3D foot trajectory, in independently walking children with cerebral palsy (CP). We performed a case control study with 14 children with CP aged 6-15 years old and 15 age-matched controls. Accuracy and precision of the foot-worn device were measured using an optical motion capture system as the reference system. Mean accuracy ± precision for both groups was 3.4 ± 4.6 cm for stride length, 4.3 ± 4.2 cm/s for speed and 0.5 ± 2.9° for strike angle. Longer stance and shorter swing phases with an increase in double support were observed in children with CP (p=0.001). Stride length, speed and peak angular velocity during swing were decreased in paretic limbs, with significant differences in strike and lift-off angles. Children with cerebral palsy showed significantly higher inter-stride variability (measured by their coefficient of variation) for speed, stride length, swing and stance. During turning trajectories speed and stride length decreased significantly (p<0.01) for both groups, whereas stance increased significantly (p<0.01) in CP children only. Foot-worn inertial sensors allowed us to analyze gait spatiotemporal data outside a laboratory environment with good accuracy and precision and congruent results with what is known of gait variations during linear walking in children with CP.


Assuntos
Acelerometria/instrumentação , Paralisia Cerebral/diagnóstico , Pé/fisiopatologia , Transtornos Neurológicos da Marcha/diagnóstico , Adolescente , Fenômenos Biomecânicos , Estudos de Casos e Controles , Paralisia Cerebral/complicações , Paralisia Cerebral/fisiopatologia , Criança , Feminino , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Humanos , Masculino
4.
Rev Med Suisse ; 9(393): 1408-13, 2013 Jul 17.
Artigo em Francês | MEDLINE | ID: mdl-23971325

RESUMO

An increasing number of anterior cruciate ligament injuries are now seen in children and girls seem to be equally affected. Such neglected or untreated lesions could be the cause of early degenerative changes. Recently, many authors support the trend toward early surgical management in skeletally immature patients with complex meniscal tear or recurrent knee instability after proper rehabilitation. Improvement in pediatric knowledge and surgical techniques tend to support a tendency for more surgical treatment in children. The type of management is choosing according to history and physical examination. Magnetic resonance imaging is a useful tool not only for diagnosis but also for surgical treatment planning. We usually recommend anterior cruciate ligament reconstruction in children with knee instability or with further damages to the joint.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior/métodos , Traumatismos do Joelho/cirurgia , Determinação da Idade pelo Esqueleto , Fatores Etários , Ligamento Cruzado Anterior/cirurgia , Criança , Feminino , Humanos , Instabilidade Articular/etiologia , Traumatismos do Joelho/diagnóstico , Traumatismos do Joelho/reabilitação , Articulação do Joelho/patologia , Articulação do Joelho/cirurgia , Imageamento por Ressonância Magnética/métodos , Masculino , Recidiva
5.
Rev Med Suisse ; 7(304): 1549-52, 2011 Aug 10.
Artigo em Francês | MEDLINE | ID: mdl-21919394

RESUMO

The physical-activity and sporting at the child and the teenager is probably, in these years 2000, in full change. In a paradoxical way, extremely sporting children or teenagers are living beside extremely sedentary school-boys, neglecting the majority of the physical-activities and preferring a home-lifestyle. In the evaluation of overload sporting lesion of at teenager, it is thus imperative to take into account not only the individual characteristics of the child: its sex, its age, its stage of growth, its psychology, the presence or not of preexistent pathologies or anatomical disorders. It is naturally necessary to wonder about the training methods of the activity, but it appears fundamental to me to evaluate the child from a sensitivo-motor point of view and this can be carried out by assessments physio-therapeutic or aptitude tests carried out by doctors of the sport.


Assuntos
Transtornos Traumáticos Cumulativos/fisiopatologia , Adolescente , Criança , Humanos , Atividade Motora/fisiologia , Esportes/fisiologia
6.
Acta Biomater ; 6(9): 3755-62, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20346421

RESUMO

Previous studies support resorbable biocomposites made of poly(L-lactic acid) (PLA) and beta-tricalcium phosphate (TCP) produced by supercritical gas foaming as a suitable scaffold for tissue engineering. The present study was undertaken to demonstrate the biocompatibility and osteoconductive properties of such a scaffold in a large animal cancellous bone model. The biocomposite (PLA/TCP) was compared with a currently used beta-TCP bone substitute (ChronOS, Dr. Robert Mathys Foundation), representing a positive control, and empty defects, representing a negative control. Ten defects were created in sheep cancellous bone, three in the distal femur and two in the proximal tibia of each hind limb, with diameters of 5 mm and depths of 15 mm. New bone in-growth (osteoconductivity) and biocompatibility were evaluated using microcomputed tomography and histology at 2, 4 and 12 months after surgery. The in vivo study was validated by the positive control (good bone formation with ChronOS) and the negative control (no healing with the empty defect). A major finding of this study was incorporation of the biocomposite in bone after 12 months. Bone in-growth was observed in the biocomposite scaffold, including its central part. Despite initial fibrous tissue formation observed at 2 and 4 months, but not at 12 months, this initial fibrous tissue does not preclude long-term application of the biocomposite, as demonstrated by its osteointegration after 12 months, as well as the absence of chronic or long-term inflammation at this time point.


Assuntos
Materiais Biocompatíveis/farmacologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Alicerces Teciduais/química , Cicatrização/efeitos dos fármacos , Animais , Substitutos Ósseos , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/cirurgia , Feminino , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Fêmur/patologia , Fêmur/cirurgia , Tamanho do Órgão/efeitos dos fármacos , Ovinos/sangue , Microtomografia por Raio-X
8.
Int Orthop ; 33(1): 27-33, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17717664

RESUMO

Freehand positioning of the femoral drill guide is difficult during hip resurfacing and the surgeon is often unsure of the implant position achieved peroperatively. The purpose of this study was to find out whether, by using a navigation system, acetabular and femoral component positioning could be made easier and more precise. Eighteen patients operated on by the same surgeon were matched by sex, age, BMI, diagnosis and ASA score (nine patients with computer assistance, nine with the regular ancillary). Pre-operative planning was done on standard AP and axial radiographs with CT scan views for the computer-assisted operations. The final position of implants was evaluated by the same radiographs for all patients. The follow-up was at least 1 year. No difference between both groups in terms of femoral component position was observed (p > 0.05). There was also no difference in femoral notching. A trend for a better cup position was observed for the navigated hips, especially for cup anteversion. There was no additional operating time for the navigated hips. Hip navigation for resurfacing surgery may allow improved visualisation and hip implant positioning, but its advantage probably will be more obvious with mini-incisions than with regular incision surgery.


Assuntos
Artroplastia de Quadril/métodos , Artroplastia de Quadril/normas , Metais , Cirurgia Assistida por Computador/métodos , Cirurgia Assistida por Computador/normas , Adulto , Artroplastia de Quadril/efeitos adversos , Índice de Massa Corporal , Feminino , Seguimentos , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Resultado do Tratamento
9.
Rev Med Suisse ; 3(105): 884-9, 2007 Apr 04.
Artigo em Francês | MEDLINE | ID: mdl-17514931

RESUMO

Femur-acetabular impingement is a recently discovered etiology of early hip osteoarthritis. Patient history and clinical examination allow to make the diagnosis, whereas the radiological exams allow to find the etiology of impingement. Impingement is related to morphological alterations of the acetabular rim and/or proximal femur, leading to an abnormal contact between the articular components. The localisation of the abnormal morphology determines the type of impingement and the resulting articular damages. Because of the increasing risk of chondral lesions, only an early treatment may eventually improve the prognosis of the hip joint. If primary conservative treatment is unsuccessful in confirmed impingement cases, open or arthroscopic surgical treatment is indicated.


Assuntos
Acetábulo/anormalidades , Acetábulo/cirurgia , Cabeça do Fêmur/anormalidades , Cabeça do Fêmur/cirurgia , Osteoartrite do Quadril/cirurgia , Acetábulo/diagnóstico por imagem , Artroscopia , Diagnóstico Diferencial , Cabeça do Fêmur/diagnóstico por imagem , Humanos , Procedimentos Ortopédicos/métodos , Osteoartrite do Quadril/diagnóstico , Radiografia , Resultado do Tratamento
10.
G Ital Med Lav Ergon ; 29(3 Suppl): 253-6, 2007.
Artigo em Italiano | MEDLINE | ID: mdl-18409672

RESUMO

The aim of this study is the objective evaluation of the visual effort in 6 public traffic controllers (4 male, 2 female, mean age 29,6), by means of electronic equipment. The electronic equipment quantify the observation distance and the observation time for each controller's occupational visual field. The quantification of these parameters is obtained by the emission of ultrasound at 40 KHz from an emission sensor (placed by the VDT screen) and the ultrasound reception by means of a receiving sensor (placed on the operator's head). The travelling time of the ultrasound (US), as the air speed is known and costant (about 340 m/s), it is used to calculate the distance between the emitting and the receiving sensor. The results show that the visual acuity required is of average level, while accommodation's and convergence's effort vary from average to intense (depending on the visual characteristics of the operator considered), ranging from 26,41 and 43,92% of accommodation and convergence available in each operator. The time actually spent in "near observation within the c.v.p." (Tscr) was maintained in a range from 2h 54' and 4h 05'.


Assuntos
Computadores , Saúde Ocupacional , Visão Ocular/fisiologia , Adulto , Feminino , Humanos , Masculino
11.
G Ital Med Lav Ergon ; 29(3 Suppl): 256-8, 2007.
Artigo em Italiano | MEDLINE | ID: mdl-18409673

RESUMO

Thirty-two voluntary subjects were selected, not suffering either from any degenerative ophthalmic diseases or refraction and ocular motility alterations. Each subject underwent close visual task experimental sessions (e.g. PC usage), under monitored experimental conditions. Aim of the study is the assessment of working efficiency effects caused by lighting conditions characterized by "according to law" illuminations, yet in presence of high or low luminance ratios in the occupational visual field". An analysis of the data showed that high luminance ratios conditions show a decrease of the performance (decrease overall efficiency, increase in the number of errors and time of execution), which where not detected with low luminance ratios conditions. Asthenopia did not show clear differences, possibly due to the effects of the intense near work which was present in both the experimental sessions.


Assuntos
Iluminação/normas , Análise e Desempenho de Tarefas , Local de Trabalho , Adolescente , Adulto , Feminino , Humanos , Masculino
12.
Rev Med Suisse ; 2(92): 2902-6, 2006 Dec 20.
Artigo em Francês | MEDLINE | ID: mdl-17233494

RESUMO

Gait disorders and lower legs deformities in children are frequent causes of parental concern and of medical advice. These deformities should be analysed systematically as well as their consequences for daily activities. We should define precisely type, localisation and importance of the deformity: femoral or tibial torsion, knock knees, bow legs. The evaluation should always be done according to age of the child because these deformities are most often a step toward adult morphotype. Sometimes they could be the manifestation of some generalised or localised pathology that should be investigated and treated. Nevertheless patience and explanations, regular follow-up allow to reassure the parents. There is in the great majority of case no place for any conservatrice and especially surgical treatment for theses disorders spontaneously healing in 95% of cases.


Assuntos
Transtornos Neurológicos da Marcha , Perna (Membro)/anormalidades , Criança , Transtornos Neurológicos da Marcha/diagnóstico , Transtornos Neurológicos da Marcha/terapia , Humanos
13.
Comput Methods Biomech Biomed Engin ; 8(5): 307-13, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16298852

RESUMO

A numerical model of the medial open wedge tibial osteotomy based on the finite element method was developed. Two plate positions were tested numerically. In a configuration, (a), the plate was fixed in a medial position and (b) in an anteromedial position. The simulation took into account soft tissues preload, muscular tonus and maximal gait load.The maximal stresses observed in the four structural elements (bone, plate, wedge, screws) of an osteotomy with plate in medial position were substantially higher (1.13-2.8 times more) than those observed in osteotomy with an anteromedial plate configuration. An important increase (1.71 times more) of the relative micromotions between the wedge and the bone was also observed. In order to avoid formation of fibrous tissue at the bone wedge interface, the osteotomy should be loaded under 18.8% (approximately 50 kg) of the normal gait load until the osteotomy interfaces union is achieved.


Assuntos
Artroplastia do Joelho/instrumentação , Artroplastia do Joelho/métodos , Placas Ósseas , Osteotomia/instrumentação , Osteotomia/métodos , Implantação de Prótese/métodos , Tíbia/fisiopatologia , Tíbia/cirurgia , Fenômenos Biomecânicos , Parafusos Ósseos , Simulação por Computador , Análise de Falha de Equipamento/métodos , Análise de Elementos Finitos , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Humanos , Modelos Biológicos , Movimento , Estresse Mecânico , Suporte de Carga
14.
J Bone Joint Surg Br ; 87(8): 1157-63, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16049257

RESUMO

In an attempt to increase the life of cementless prostheses, an hydroxyapatite-coated implant which releases a bisphosphonate has been suggested as a drug-delivery system. Our in vitro study was designed to determine the maximum dose to which osteoblasts could be safely exposed. Our findings demonstrated that zoledronate did not impair the proliferation of human osteoblasts when used at concentrations below 1 microm. Murine cells can be exposed to concentrations as high as 10 microm.A concentration of 0.01% of titanium particles did not impair the proliferation of either cell line. Zoledronate affected the alkaline phosphatase activity of murine osteoblasts through a chelation phenomenon. The presence of titanium particles strongly decreased the alkaline phosphatase activity of murine osteoblasts. We did not detect any synergic effect of zoledronate and titanium particles on the behaviour of both human and murine osteoblasts.


Assuntos
Difosfonatos/toxicidade , Imidazóis/toxicidade , Osteoblastos/efeitos dos fármacos , Titânio/farmacologia , Fosfatase Alcalina/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Materiais Revestidos Biocompatíveis , Relação Dose-Resposta a Droga , Interações Medicamentosas , Humanos , Hidroxiapatitas , Camundongos , Osteoblastos/citologia , Osteoblastos/enzimologia , Ácido Zoledrônico
15.
Rev Med Suisse ; 1(12): 844-8, 2005 Mar 23.
Artigo em Francês | MEDLINE | ID: mdl-15865358

RESUMO

The results of the total hip prostheses in terms of cost-efficiency make one of the surgical procedures the most efficient. Usually, the articular pains disappear completely and the patient function improves. Outside, turned out failures, which require a revision, some patients present residual pain persisting after the intervention or appearing secondarily. Considering the important number of total hip arthroplasties, this clinical situation is not so rare and the generalist, as the specialist, can be confronted there. The experience shows that the surgical revisions, in the absence of a precise diagnosis are disappointing and often do not improve the patient. This article presents the diagnostic and therapeutic steps advised to face this problem.


Assuntos
Artroplastia de Quadril/efeitos adversos , Dor Pós-Operatória/etiologia , Diagnóstico Diferencial , Articulação do Quadril/diagnóstico por imagem , Humanos , Falha de Prótese , Infecções Relacionadas à Prótese/diagnóstico , Radiografia , Cintilografia
16.
Bone ; 36(1): 52-60, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15664002

RESUMO

Despite total hip replacement (THR) gives generally satisfactory results, the quality of outcome in young patients is markedly decreased compared to the average THR outcome. For this population, pharmacological treatment with bisphosphonate would be beneficial to decrease the peri-implant osteolysis. However, as this population does not necessarily suffer from osteoporosis, a nonsystemic treatment would be preferable. Zoledronate was then grafted to hydroxyapatite (HA) coating of titanium implants. The implants were inserted in rat condyles with various zoledronate concentrations. A positive concentration-dependent effect was observed on the peri-implant bone density and on different histomorphometric parameters. Importantly for the outcome of the implants, the mechanical fixation was increased by the local presence of zoledronate. The obtained results open the way of an easy transformation of currently existing HA-coated implants by grafting bisphosphonate onto the coating in order to increase their service life in the patients.


Assuntos
Fosfatos de Cálcio/administração & dosagem , Difosfonatos/administração & dosagem , Imidazóis/administração & dosagem , Osseointegração , Animais , Sistemas de Liberação de Medicamentos , Feminino , Microscopia Eletrônica de Varredura , Próteses e Implantes , Ratos , Ratos Wistar , Titânio , Ácido Zoledrônico
17.
Artigo em Inglês | MEDLINE | ID: mdl-15203955

RESUMO

In order to decrease the peri-implant bone loss during the life-time of the implant, oral use of anti-osteoporosis drugs (like bisphosphonates) has been suggested. In this study, bone remodeling parameters identified from clinical trials of alendronate were used to simulate the effect of those drugs used after total hip arthroplasty on the peri-implant bone density. Results of the simulation show that the oral administrated drugs increase bone density around the implant and decreases, at the same time, the micromovements between the implant and the surrounding bone tissue. Incorporation of drug effect in numerical studies of bone remodeling is a promising tool especially to predetermine safe bisphosphonate doses that could be used with orthopedic implants.


Assuntos
Alendronato/administração & dosagem , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Prótese de Quadril/efeitos adversos , Modelos Biológicos , Osteoporose/prevenção & controle , Osteoporose/fisiopatologia , Administração Oral , Artroplastia de Quadril/efeitos adversos , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Simulação por Computador , Relação Dose-Resposta a Droga , Quimioterapia Assistida por Computador/métodos , Análise de Falha de Equipamento/métodos , Fêmur/efeitos dos fármacos , Fêmur/fisiopatologia , Fêmur/cirurgia , Análise de Elementos Finitos , Humanos , Osteoporose/etiologia , Falha de Prótese , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/fisiopatologia , Infecções Relacionadas à Prótese/prevenção & controle , Resultado do Tratamento
18.
Ann Occup Hyg ; 48(1): 29-38, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14718343

RESUMO

OBJECTIVES: The assessment of lighting conditions in workplaces has traditionally focused on the measurement of illuminance. The rationale for a new method for the detailed evaluation of natural and artificial light in 'near work' situations, involving the assessment of luminance, is described. METHODS: The procedure comprises four successive phases: (1) identify object/images observed during work tasks; (2) outline the area of the operator's visual field where gaze is predominantly directed; (3) measure luminances in the visual field, pin-pointing all sources of primary and secondary luminance, and constructing iso-luminance maps; and (4) compare luminance ratios. RESULTS: The procedure was illustrated using the common example of near work in an office environment. Illuminance was found to be inadequate to evaluate the effects of natural and artificial environmental light in the workplace. This is due to the fact that the luxmeter is designed to integrate the light detected over a large angle, whereas in near work the operator's retina is mainly stimulated by light originating from objects/images placed in the occupational visual field. CONCLUSIONS: A detailed measurement of luminance within the occupational visual field is consistent with ocular anatomy and physiology, and can be used as part of a risk assessment for visual disturbances and to rationalize lighting at workstations.


Assuntos
Astenopia/prevenção & controle , Iluminação/normas , Doenças Profissionais/prevenção & controle , Campos Visuais/fisiologia , Terminais de Computador/normas , Sensibilidades de Contraste , Humanos , Saúde Ocupacional , Fotometria
19.
Med Lav ; 94(1): 101-7, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-12768961

RESUMO

In 1979 it was decided to activate, within the Institute of Occupational Health of the Milan "Università degli Studi", a new Unit of Ergophthalmology. This decision was taken owing to the progressive diffusion of "optical instruments", particularly computer-based equipment, in the world of work and to the relevance that this topic assumed among Italian occupational physicians. Since its beginning, one of the main characteristics of the Ergophthalmology Unit was an interdisciplinary approach, where occupational physicians, ophthalmologists, occupational hygienists and lighting engineers were collaborating on a daily basis. Research activities, which developed over many years and in several phases, were concerned with four main topics: 1. analysis and quantification of "near work load"; initially the investigations were mainly aimed at the evaluation of the observation distance in different tasks, followed by the development of a method which, by means of specifically designed electronic equipment, allows quantification of the accommodation and convergence required by the task; 2. development of a new method aimed at evaluating, by a photometric procedure, the luminance ratios in the "occupational visual field"; this research was carried out, both in the laboratory and during on-site investigations, in collaboration with the Dept. of Electrotechnics of Milan Polytechnic; 3. studies on the relationships between indoor microbial pollution and Computer Assisted Design work, considering that ocular conjunctiva and cornea, due to their external position, can be easily inoculated by micro-organisms present on periocular tissue and hands; this research showed that bacteria and fungi pathogenic for the eye (Staphylococcus aureus, Candida sp., Aspergillus sp.) are present on desk, keyboard and mouse, as well as in the conjunctival sac of the exposed operators; 4. studies on "blue light" and its effects on the Pigmented Retinal Epithelium (PRE) in workers exposed to halide lamps, like electricians, installers, maintenance staff, polymerization operators, etc.; the laboratory and on-site investigation that was carried out in cooperation with the Health Physics Dept. of the Milan ICP Hospital, showed that long-term exposure to low levels of irradiation could constitute an eye risk for these working populations.


Assuntos
Ergonomia , Medicina do Trabalho/tendências , Oftalmologia/tendências , Universidades/organização & administração , Terminais de Computador , Comportamento Cooperativo , Microbiologia Ambiental , Oftalmopatias/etiologia , Oftalmopatias/prevenção & controle , Infecções Oculares/etiologia , Infecções Oculares/prevenção & controle , Humanos , Iluminação , Doenças Profissionais/etiologia , Doenças Profissionais/prevenção & controle , Exposição Ocupacional , Fotometria
20.
Ergonomics ; 44(6): 668-76, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11373027

RESUMO

Modern work activities often require an intense and prolonged visual effort on near objects. At the same time, occupational asthenopia caused by accommodation and binocularity overloading is a very common complaint in these working populations. Moreover, blinking rate seems to be a sensitive parameter with 'indoor-near-work operators', possibly increased by both chemical and physical environmental agents and decreased by cognitive effort. In this paper, a new piece of electronic equipment used to measure the observation distance and blinking rate is described.


Assuntos
Astenopia , Piscadela/fisiologia , Eletrônica/instrumentação , Percepção Visual/fisiologia , Trabalho/fisiologia , Poluição do Ar em Ambientes Fechados , Terminais de Computador , Ergonomia , Humanos , Itália , Exposição Ocupacional/análise , Projetos de Pesquisa
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