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2.
Lasers Med Sci ; 36(4): 829-835, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32748167

RESUMO

Long-pulsed 1064-nm (LP1064) and 755-nm (LP755) lasers have been demonstrated as effective treatments for leg veins. However, few studies of these treatments on Asian skin type as well as direct comparison between two methods were reported. The aim of this study was to compare the clinical efficacy and safety of LP1064 with LP755 in the treatment of C1 leg veins on skin type IV patients. Patients with symmetric matched areas C1 leg veins were treated with single session of LP1064 for the right and LP755 for the left. Treated areas of every patient were divided into matrices of 2 × 2 cm squares. Vessels in the highest density squares were subjected to evaluation. Spot sizes were 5 mm fixed. Pulse durations and fluences were according to vessel diameters and endpoints, respectively. The clearances were evaluated at 1 and 3 months post treatment. Side effects were recorded immediately, 10 min, 24 h, and 1 and 3 months after treatment. Twenty-two patients were enrolled with total 96 vessels from 22 selected squares in the right and 106 vessels from 22 selected squares in the left. At 1-month follow-up, the clearances of LP1064 and LP755 were not significantly different (71.87% and 71.69%, respectively; p = 0.99). At 3-month follow-up, the efficacies were constant and no recurrence occurred. Pain levels of both methods were moderate and significantly lower in LP755. These findings suggest that LP1064 and LP755 laser treatments were comparatively effective and safe for C1 leg veins of skin type IV patients.


Assuntos
Terapia a Laser , Perna (Membro)/efeitos da radiação , Telangiectasia/cirurgia , Adulto , Humanos , Terapia a Laser/efeitos adversos , Masculino , Pessoa de Meia-Idade , Segurança , Resultado do Tratamento
3.
Radiother Oncol ; 127(3): 449-455, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29631933

RESUMO

BACKGROUND/PURPOSE: To evaluate the pattern of manifestation and risk factors for lower limb edema (LLE) within the prospective, observational, multi-center EMBRACE study on radiochemotherapy and MRI-guided brachytherapy in locally advanced cervical cancer (LACC). MATERIAL/METHODS: LLE was prospectively assessed according to the physician-reported CTCAE v.3 and patient-reported EORTC QLQ-CX24 questionnaire at baseline and regular follow-up. RESULTS: In total, 1176 patients were evaluated with a median follow-up of 27 months. Actuarial analyses revealed 3/5-year estimates of 27%/31% of CTCAE G ≥ 1, 6.1%/6.6% of G ≥ 2 and 0.5%/0.5% for G ≥ 3. Prevalence rates for G ≥ 1 LLE at 3 months, 1, 3 and 5 years after end of treatment were 7%, 12%, 12%, 15% for physician-assessed and 25%, 30%, 30%, 34% for any patient-reported symptoms and showed a steady increase over time. Invasive lymph node staging and obesity at diagnosis are independent significant risk factors for G ≥ 1 LLE, whereas nodal boost has no impact. Extended radiation fields including para-aortic and/or inguinal nodes show a tendency to increase the risk. CONCLUSION: Severe LLE after definitive radiochemotherapy in LACC is rare. However, the risk for mild LLE is considerable, and related to patient-, diagnostic- and treatment characteristics. Less invasive diagnostic surgical procedures or non-invasive assessment, less invasive radiotherapy management and active rehabilitation are important pathways for future developments.


Assuntos
Braquiterapia/efeitos adversos , Edema/etiologia , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/métodos , Quimiorradioterapia/efeitos adversos , Cisplatino/efeitos adversos , Cisplatino/uso terapêutico , Edema/induzido quimicamente , Feminino , Humanos , Perna (Membro)/patologia , Perna (Membro)/efeitos da radiação , Linfonodos/patologia , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos , Radioterapia Guiada por Imagem/efeitos adversos , Radioterapia Guiada por Imagem/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/radioterapia , Adulto Jovem
4.
Lasers Med Sci ; 33(2): 329-336, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29101708

RESUMO

The purpose of this study was to verify the photobiomodulation therapy (PBMT) effects with different doses on neuromuscular economy during submaximal running tests. Eighteen male recreational runners participate in a randomized, double-blind, and placebo-controlled trial, which each participant was submitted to the same testing protocol in five conditions: control, placebo, and PBMT with doses of 15, 30, and 60 J per site (14 sites in each lower limb). The submaximal running was performed at 8 and 9 km h-1 during 5 min for each velocity. Muscle activation of the vastus lateralis (VL), vastus medialis (VM), rectus femoris (RF), biceps femoris (BF), and gastrocnemius lateralis (GL) was collected during the last minute of each running test. The root mean square (RMS) was normalized by maximal isometric voluntary contraction (MIVC) performed a priori in an isokinetic dynamometer. The RMS sum of all muscles (RMSLEG) was considered as main neuromuscular economy parameter. PBMT with doses of 15, 30, and 60 J per site [33 diodes = 5 lasers (850 nm), 12 LEDs (670 nm), 8 LEDs (880 nm), and 8 LEDs (950 nm)] or placebo applications occurred before running tests. For the statistical analysis, the effect size was calculated. Moreover, a qualitative inference was used to determine the magnitude of differences between groups. Peak torque and RMS during MIVCs showed small effect sizes. According to magnitude-based inference, PBMT with dose of 15 J per site showed possibly and likely beneficial effects on neuromuscular economy during running at 8 and 9 km h-1, respectively. On other hand, PBMT with doses of 30 and 60 J per site showed possible beneficial effects only during running at 9 km h-1. We concluded that PBMT improve neuromuscular economy and the best PBMT dose was 15 J per site (total dose of 420 J).


Assuntos
Terapia com Luz de Baixa Intensidade , Corrida/fisiologia , Adulto , Relação Dose-Resposta à Radiação , Método Duplo-Cego , Eletromiografia , Humanos , Contração Isométrica/efeitos da radiação , Perna (Membro)/fisiologia , Perna (Membro)/efeitos da radiação , Masculino , Músculo Esquelético/fisiologia , Músculo Esquelético/efeitos da radiação , Torque
5.
Circulation ; 136(25): 2406-2416, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-29054934

RESUMO

BACKGROUND: Radiation exposure during fluoroscopically guided interventions such as endovascular aortic repair (EVAR) is a growing concern for operators. This study aimed to measure DNA damage/repair markers in operators perfoming EVAR. METHODS: Expression of the DNA damage/repair marker, γ-H2AX and DNA damage response marker, phosphorylated ataxia telangiectasia mutated (pATM), were quantified in circulating lymphocytes in operators during the peri-operative period of endovascular (infrarenal, branched, and fenestrated) and open aortic repair using flow cytometry. These markers were separately measured in the same operators but this time wearing leg lead shielding in addition to upper body protection and compared with those operating with unprotected legs. Susceptibility to radiation damage was determined by irradiating operators' blood in vitro. RESULTS: γ-H2AX and pATM levels increased significantly in operators immediately after branched endovascular aortic repair/fenestrated endovascular aortic repair (P<0.0003 for both). Only pATM levels increased after infrarenal endovascular aortic repair (P<0.04). Expression of both markers fell to baseline in operators after 24 hours (P<0.003 for both). There was no change in γ-H2AX or pATM expression after open repair. Leg protection abrogated γ-H2AX and pATM response after branched endovascular aortic repair/fenestrated endovascular aortic repair. The expression of γ-H2AX varied significantly when operators' blood was exposed to the same radiation dose in vitro (P<0.0001). CONCLUSIONS: This is the first study to detect an acute DNA damage response in operators performing fluoroscopically guided aortic procedures and highlights the protective effect of leg shielding. Defining the relationship between this response and cancer risk may better inform safe levels of chronic low-dose radiation exposure.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Dano ao DNA/efeitos da radiação , Exposição Ocupacional , Radiação Ionizante , Adulto , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Procedimentos Endovasculares , Feminino , Fluoroscopia , Histonas/metabolismo , Humanos , Imuno-Histoquímica , Perna (Membro)/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Fosforilação , Proteção Radiológica/instrumentação , Linfócitos T/metabolismo , Linfócitos T/efeitos da radiação
6.
Phys Med Biol ; 61(22): 8010-8024, 2016 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-27779135

RESUMO

Accurate assessment of range uncertainty is critical in proton therapy. However, there is a lack of data and consensus on how to evaluate the appropriate amount of uncertainty. The purpose of this study is to quantify the range uncertainty in various treatment conditions in proton therapy, using transmission measurements through various animal tissues. Animal tissues, including a pig head, beef steak, and lamb leg, were used in this study. For each tissue, an end-to-end test closely imitating patient treatments was performed. This included CT scan simulation, treatment planning, image-guided alignment, and beam delivery. Radio-chromic films were placed at various depths in the distal dose falloff region to measure depth dose. Comparisons between measured and calculated doses were used to evaluate range differences. The dose difference at the distal falloff between measurement and calculation depends on tissue type and treatment conditions. The estimated range difference was up to 5, 6 and 4 mm for the pig head, beef steak, and lamb leg irradiation, respectively. Our study shows that the TPS was able to calculate proton range within about 1.5% plus 1.5 mm. Accurate assessment of range uncertainty in treatment planning would allow better optimization of proton beam treatment, thus fully achieving proton beams' superior dose advantage over conventional photon-based radiation therapy.


Assuntos
Cabeça/efeitos da radiação , Perna (Membro)/efeitos da radiação , Terapia com Prótons , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Algoritmos , Animais , Bovinos , Simulação por Computador , Relação Dose-Resposta à Radiação , Humanos , Ovinos , Suínos , Incerteza
7.
Intern Med ; 51(17): 2263-70, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22975533

RESUMO

BACKGROUND: Systemic thermal therapy (STT) has been associated with beneficial effects in patients with chronic heart failure (CHF). The fact, however, that it requires a dedicated as well as spacious facility and trained personnel makes it difficult to practice in the daily care of patients with CHF. OBJECTIVE: The aim of this study was to determine whether the leg thermal therapy (LTT) has a positive impact similar to that of STT in patients with CHF. Methods and Results Twenty patients with CHF (57 ± 17 years old, left ventricular ejection fraction=30 ± 10%) received LTT (45°C) for 20 minutes. Immediately after the treatment, the core temperature had increased (+0.3 ± 0.3°C) (p<0.01). While the LTT had no significant effects on the heart rate, systolic arterial pressure, and diastolic blood pressure, it increased the cardiac output (mixed venous oxygen saturation; +2 ± 3%) and decrease the pulmonary capillary wedge pressure (-2 ± 2 mmHg). The LTT significantly improved the flow-mediated vasodilatation (FMD) from 4.8 ± 2.6 to 7.1 ± 3.6%, the antioxidative markers, thiol from 4.0 ± 0.7 to 4.5 ± 0.9 µmoL/g, and the marker of oxidative deoxyribonucleic acid (DNA) damage, urine 8-hydroxy-2'deoxyguanosine (8OHdG) from 100 to 82 ± 3%, respectively (p<0.05). No patient had any adverse effects associated with LTT. Conclusion LTT acutely improved FMD, and oxidative stress in patients with CHF. Although the long-term effect of LTT remains to be investigated, its practicality which is comparable to that of STT would make it an attractive therapeutic strategy for patients with CHF.


Assuntos
Endotélio Vascular/efeitos da radiação , Insuficiência Cardíaca/terapia , Hemodinâmica/efeitos da radiação , Hipertermia Induzida/métodos , Raios Infravermelhos/uso terapêutico , Perna (Membro)/efeitos da radiação , Estresse Oxidativo/efeitos da radiação , Idoso , Antioxidantes/metabolismo , Temperatura Corporal/fisiologia , Temperatura Corporal/efeitos da radiação , Débito Cardíaco/fisiologia , Débito Cardíaco/efeitos da radiação , Doença Crônica , Endotélio Vascular/fisiopatologia , Feminino , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/fisiologia , Humanos , Perna (Membro)/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Pressão Propulsora Pulmonar/fisiologia , Pressão Propulsora Pulmonar/efeitos da radiação , Vasodilatação/fisiologia , Vasodilatação/efeitos da radiação
8.
Radiat Prot Dosimetry ; 150(3): 306-11, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22234422

RESUMO

Radiation exposure of the operator during cardiac catheter ablation procedures was assessed for an experienced cardiologist adopting various measures of radiation protection and utilised electroanatomic navigation. Chip thermoluminescent dosemeters were placed at the eyes, chest, wrists and legs of the operator. The ranges of fluoroscopy time and air kerma area product values associated with cardiac ablation procedures were wide (6.3-48.3 min and 1.7-80.3 Gy cm(2), respectively). The measured median radiation doses per procedure for each monitored position were 23.6 and 21.3 µSv to the left and right wrists, respectively, 25.3 and 30.4 µSv to the left and right legs, respectively. The doses to the eyes were below the minimum detectable dose of 9 µSv. The estimated median effective dose was 22.5 µSv. Considering the actual workload of the operator, the calculated annual doses to the hands, legs and eyes, as well as the annual effective dose, were all below the corresponding limits. The findings of this study indicate that cardiac ablation procedures performed at a modern laboratory do not impose a high radiation hazard to the operator when radiation protection measures are routinely adopted.


Assuntos
Arritmias Cardíacas/terapia , Ablação por Cateter/efeitos adversos , Técnicas Eletrofisiológicas Cardíacas/efeitos adversos , Exposição Ocupacional/prevenção & controle , Proteção Radiológica , Adulto , Idoso , Ablação por Cateter/normas , Técnicas Eletrofisiológicas Cardíacas/normas , Olho/efeitos da radiação , Feminino , Fluoroscopia , Humanos , Perna (Membro)/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/análise , Radiografia Intervencionista , Dosimetria Termoluminescente , Tórax/efeitos da radiação , Punho/efeitos da radiação , Adulto Jovem
10.
Int J Radiat Oncol Biol Phys ; 80(4): 1158-63, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20888134

RESUMO

PURPOSE: The incidental irradiation (RT) of adjacent bone that takes place during treatment of soft tissue extremity sarcomas is generally presumed to "weaken" the bone by decreasing its density, which subsequently increases the risk for pathologic fracture. This investigation intended to assess the relative effects on bone density of both RT and diminished mechanical loading secondary to tumor-induced and therapy-induced functional extremity impairment. METHODS AND MATERIALS: 19 patients treated with surgical excision and RT for soft tissue extremity sarcomas had bone density measured using dual energy X-ray absorptiometry at four sites: the irradiated (A) and contralateral (B) bone, and an uninvolved bone (C) in the treated extremity and its contralateral counterpart (D). Analysis included (1) [A-B], (2) [C-D], (3) [(A-B), - (C-D)], and (4) [(A-B)/B - (C-D)/D]. RESULTS: The mean bone density for all irradiated sites was increased 0.08 ± 0.22 g/cm(2) (variance) compared to the contralateral unirradiated side when corrected for weight-bearing effects (3). An average increase in bone density of 9 ± 22% (p = 0.08) was also seen when the differences were divided by individual control densities to normalize variation in density of different anatomic sites (4). CONCLUSIONS: RT does not routinely decrease bone density when corrected for weight bearing or mechanical effects. The pathogenesis for the known increased risk of pathologic fracture in irradiated bones is likely multifactorial, including possible alterations in bone remodeling that can result in stable, or even increased, bone density. Further clinical and basic studies are needed to confirm our unexpected findings.


Assuntos
Densidade Óssea/efeitos da radiação , Fraturas Espontâneas/etiologia , Perna (Membro)/efeitos da radiação , Lesões por Radiação/complicações , Sarcoma/radioterapia , Neoplasias de Tecidos Moles/radioterapia , Adulto , Idoso , Densidade Óssea/fisiologia , Fracionamento da Dose de Radiação , Humanos , Perna (Membro)/fisiopatologia , Pessoa de Meia-Idade , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/cirurgia , Suporte de Carga/fisiologia , Adulto Jovem
11.
Radiat Prot Dosimetry ; 144(1-4): 540-2, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21051432

RESUMO

A severe irradiation accident involving a victim occurred in April 2009 in South America. The victim has found a (192)Ir source fallen from a gammagraphy device and has put it in the left pocket of his pants. Very quickly, an erythema and a blister appeared on the left leg of the victim involving hospitalisation. Following the request of the IAEA assistance, the Ionizing Radiation Dosimetry Laboratory of IRSN was asked to perform a numerical dosimetric reconstruction. A personalised voxel phantom of the victim has been constructed thanks to the Simulation of External Source Accident with Medical images tool developed by the laboratory, and a calculation of the dose with the MCNPX computer code allowed to determine the boundary of the necrotic dose at 25 Gy. On the basis of these calculations, the physicians have performed exeresis of the necrotic region on the left leg on 4 May 2009. Associated with mesenchymal stem cell injection, the leg of the victim was healthy on December 2009.


Assuntos
Perna (Membro)/efeitos da radiação , Células-Tronco Mesenquimais/efeitos da radiação , Liberação Nociva de Radioativos , Radiometria/instrumentação , Planejamento em Desastres , Humanos , Radioisótopos de Irídio/farmacologia , Masculino , Método de Monte Carlo , Necrose , Imagens de Fantasmas , Doses de Radiação , Proteção Radiológica/métodos , Radiometria/métodos , Software , América do Sul , Fatores de Tempo
12.
Br J Radiol ; 84(1003): 639-48, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21159809

RESUMO

OBJECTIVE: Assessment of the potential doses to the hands and eyes for interventional radiologists and cardiologists can be difficult. A review of studies of doses to interventional operators reported in the literature has been undertaken. METHODS: Distributions for staff dose to relevant parts of the body per unit dose-area product and for doses per procedure in cardiology have been analysed and mean, median and quartile values derived. The possibility of using these data to provide guidance for estimation of likely dose levels is considered. RESULTS: Dose indicator values that could be used to predict orders of magnitude of doses to the eye, thyroid and hands from interventional operator workloads have been derived, based on the third quartile values, from the distributions of dose results analysed. CONCLUSION: Dose estimates made in this way could be employed in risk assessments when reviewing protection and monitoring requirements. Data on the protection provided by different shielding and technique factors have also been reviewed to provide information for risk assessments. Recommendations on the positions in which dosemeters are worn should also be included in risk assessments, as dose measurements from suboptimal dosemeter use can be misleading.


Assuntos
Olho/efeitos da radiação , Perna (Membro)/efeitos da radiação , Exposição Ocupacional/prevenção & controle , Proteção Radiológica/normas , Radiografia Intervencionista/métodos , Glândula Tireoide/efeitos da radiação , Carga Corporal (Radioterapia) , Feminino , Humanos , Masculino , Doses de Radiação , Radiografia Intervencionista/efeitos adversos , Medição de Risco , Dosimetria Termoluminescente/métodos , Fatores de Tempo
13.
Photochem Photobiol Sci ; 8(8): 1195-201, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19639123

RESUMO

Measurements of anatomical UV exposure distribution were made using miniaturized polysulfone dosimeters over a four year period between 2005 and 2008 in Toowoomba, Australia (28 degrees S, 152 degrees E). Anatomical UV exposures were expressed relative to the horizontal plane ambient UV. The UV exposures were compared with existing data detailing the anatomical distribution of basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and solar keratoses (SK). Surface UV exposures to unprotected skin surfaces have been presented for each of the face, neck, arm, hand and leg assessing a total of 1453 body sites (2491 measurements). Measured exposures are presented for the human facial region to a resolution of 5 mm. The median anatomical UV expressed relative to the horizontal plane ambient UV for each of the face, neck, forearm, hand and leg regions of the body varied from 26%, 23%, 13%, 30% and 12% respectively in the 0 degrees-30 degrees SZA range; 39%, 36%, 17%, 35% and 23% in the 30 degrees-50 degrees SZA range; and 48%, 59%, 41%, 42% and 47% in the 50 degrees-80 degrees SZA range. Detailed positions of UV exposure measured over the face, neck, arm, hand and leg were more closely related to NMSC incidence data for the face and upper limbs. Further analysis with existing facial BCC and SK density data did not however show a direct relationship with the measured UV exposures highlighting the importance of other factors influencing the causation and localisation of facial NMSC.


Assuntos
Carcinoma Basocelular/epidemiologia , Carcinoma de Células Escamosas/epidemiologia , Ceratose/epidemiologia , Pele/patologia , Raios Ultravioleta , Braço/patologia , Braço/efeitos da radiação , Austrália/epidemiologia , Relação Dose-Resposta à Radiação , Exposição Ambiental , Face/patologia , Face/efeitos da radiação , Mãos/patologia , Mãos/efeitos da radiação , Humanos , Incidência , Perna (Membro)/patologia , Perna (Membro)/efeitos da radiação , Pescoço/patologia , Pescoço/efeitos da radiação , Pele/efeitos da radiação
14.
Int J Radiat Biol ; 83(10): 639-52, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17729159

RESUMO

PURPOSE: To evaluate the relationship between an estimated integral total body radiation dose delivered and phosphorylated histone H2AX protein (gamma-H2AX) foci formation in peripheral blood lymphocytes of cancer patients. MATERIAL AND METHODS: gamma-H2AX formation was quantified as the mean number of foci per lymphocyte (N(meanH2AX)) and the percentage of lymphocytes with > or =n foci. The integrated total body radiation dose was estimated from the dose volume histogram of patient's body corrected for the proportion of the body scanned by computed tomography for 3D treatment planning. RESULTS: There was a strong linear correlation between the mean number of gamma-H2AX foci per lymphocyte in the peripheral blood sample and integrated total body radiation dose (r = 0.83, p < 0.0001). The slope of the relationship was dependent on the site of body irradiated. In comparison to chest irradiation with a slope of 8.7 +/- 0.8 foci Gy(-1), the slopes for brain, upper leg and pelvic sites were significantly shallower by -4.7, -4.3, and -3.8 Gy(-1), respectively (p < 0.0001), while the slope for upper abdomen irradiation was significantly larger by 9.1 +/- 2.6 Gy(-1) (p = 0.0007). There was a slight time effect since the start of radiotherapy on the slopes of the in vivo dose responses leading to shallower slopes (-1.5 +/- 0.7 Gy(-1), p = 0.03) later (> or =10 day) during radiotherapy. After in vitro irradiation, lymphocytes showed 10.41 +/- 0.12 foci per Gy with no evidence of inter-individual heterogeneity. CONCLUSIONS: gamma-H2AX measurements in peripheral lymphocytes after local radiotherapy allow the estimation of the applied integral body dose. The site and time dependence have to be considered.


Assuntos
Abdome/efeitos da radiação , Encéfalo/efeitos da radiação , Histonas/sangue , Perna (Membro)/efeitos da radiação , Linfócitos/efeitos da radiação , Pelve/efeitos da radiação , Planejamento da Radioterapia Assistida por Computador , Abdome/patologia , Encéfalo/patologia , Fracionamento da Dose de Radiação , Relação Dose-Resposta à Radiação , Humanos , Perna (Membro)/patologia , Linfócitos/sangue , Pelve/patologia , Tolerância a Radiação , Planejamento da Radioterapia Assistida por Computador/efeitos adversos , Planejamento da Radioterapia Assistida por Computador/instrumentação , Planejamento da Radioterapia Assistida por Computador/métodos , Fatores de Tempo
15.
Radiat Prot Dosimetry ; 118(2): 190-5, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16581921

RESUMO

A general overview is given on the use of extremity dosemeters, their calibration, the units and phantoms to be used. One of the major applications of extremity dosemeters is to monitor the personnel in a hospital environment. In nuclear medicine, brachytherapy and interventional radiology (IR) skin doses to hands and legs can be substantial. Here, we report on two studies that are presently being undertaken in Belgium. The first one tries to map the dose distribution on the hands, in function of the manipulation in nuclear medicine. Some preliminary results are also given from a nationwide survey study for patient and personnel doses during IR and cardiology. The radiologists' hands, legs and forehead are monitored during a whole range of procedures in different hospitals.


Assuntos
Exposição Ocupacional , Monitoramento de Radiação/métodos , Radiometria/métodos , Bélgica , Braquiterapia/métodos , Calibragem , Testa/efeitos da radiação , Mãos/efeitos da radiação , Hospitais , Humanos , Perna (Membro)/efeitos da radiação , Imagens de Fantasmas , Equipamentos de Proteção , Monitoramento de Radiação/instrumentação , Proteção Radiológica/métodos , Radiometria/instrumentação , Radioterapia/métodos
16.
Neurosci Lett ; 393(1): 51-5, 2006 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-16207512

RESUMO

The purpose of this study was to examine the effect of Transcutaneous Electrical Nerve Stimulation (TENS) applied to the posterior aspect of the legs, on postural sway during stance. Thirty healthy subjects were tested while standing on a force platform under four stimulation conditions: no TENS, bilateral TENS, and unilateral left and right TENS. Thirty-second long tests, employing detection threshold amplitudes, were performed in three blocks. In each block, the four conditions were applied both with and without vision in a random order. The results indicate that the application of TENS brought about a decrease in postural sway as expressed by average sway velocity, in addition to a decrease in the absolute values of maximal and minimal medio-lateral and anterior-posterior velocity. Thus, similar to sub-threshold random electrical noise, it appears that the application of low-amplitude TENS to the lower limbs decreases postural sway during stance. Considering the ease of TENS application and the high prevalence of postural disorders, the potential clinical significance of this observation is to be determined by further studies.


Assuntos
Perna (Membro)/inervação , Perna (Membro)/efeitos da radiação , Movimento/efeitos da radiação , Equilíbrio Postural/fisiologia , Postura/fisiologia , Estimulação Elétrica Nervosa Transcutânea , Adulto , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Movimento/fisiologia , Limiar Sensorial/fisiologia , Limiar Sensorial/efeitos da radiação , Testes de Função Vestibular/métodos
17.
Phys Med Biol ; 48(19): 3143-55, 2003 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-14579857

RESUMO

Of the biological effects of human exposure to radiofrequency and microwave radiation, the best-established are those due to elevation of tissue temperature. To prevent harmful levels of heating, restrictions have been proposed on the specific absorption rate (SAR). However, the relationship between SAR and temperature rise is not an invariant, since not only the heat capacity but also the efficiency of heat dissipation varies between different tissues and exposure scenarios. For small enough SAR, the relationship is linear and may be characterized by a 'heating factor' deltaT/SAR. Under whole-body irradiation the SAR may be particularly high in the ankles due to the concentration of current flowing through a relatively small cross-sectional area. In a previous paper, the author has presented calculations of the SAR distribution in a human leg in the high frequency (HF) band. In this paper, the heating factor for this situation is derived using a finite element approximation of the Pennes bioheat equation. The sensitivity of the results to different blood perfusion rates is investigated, and a simple local thermoregulatory model is applied. Both time-dependent and steady-state solutions are considered. Results confirm the appropriateness of the ICNIRP reference level of 100 mA on current through the leg, but suggest that at higher currents significant thermoregulatory adjustments to muscle blood flow will occur.


Assuntos
Temperatura Corporal/fisiologia , Temperatura Corporal/efeitos da radiação , Campos Eletromagnéticos , Perna (Membro)/fisiologia , Perna (Membro)/efeitos da radiação , Modelos Biológicos , Ondas de Rádio , Radiometria/métodos , Carga Corporal (Radioterapia) , Simulação por Computador , Impedância Elétrica , Transferência de Energia/fisiologia , Análise de Elementos Finitos , Humanos , Perna (Membro)/irrigação sanguínea , Doses de Radiação , Eficiência Biológica Relativa , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Lasers Surg Med ; 31(5): 359-62, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12430154

RESUMO

BACKGROUND AND OBJECTIVES: The treatment of larger leg veins with laser or intense pulsed light often shows varying degrees of success and inconsistent clinical response rates. Aim of this study was to evaluate the effectiveness and safety of the 755 nm long pulsed high fluence alexandrite laser in the treatment of larger leg veins. STUDY DESIGN/MATERIALS AND METHODS: Twenty female volunteers aged 25-51 years (mean 39) with 0.3-1.3 mm leg telangiectasias received laser treatment, 10 of them with an additional pass done right after the first pass. Their skin type ranged from 1 to 3 (five type 1, seven type 2, eight type 3). After test spots with increasing fluences (40-90 J/cm(2)) to determine the individual safe fluence, the maximum fluence of 90 J/cm(2) could be used in all 20 subjects. The spot size was 3 x 10 mm, a spray cooling system was used with 80 milliseconds spray and delay time, respectively. The number of pulses administered ranged from 30 to 467 per subject (mean 139). The treated area was controlled 1 day, 1 month, and 3 months post-treatment and the side effects were quantified. At each visit, the treatment area was photographed. The percent clearance in the treated areas was scored by two observers. Subject satisfaction was evaluated at the 3 months post-treatment visit. RESULTS: After 3 months, in all 20 test subjects some clearance was visible. It ranged from low-grade to complete clearance. Most subjects (15 of 20) had a clearance between 26 and 75%. Hyperpigmentation was observed in 15 subjects. Hypopigmentation was seen in two subjects. No edema, no purpura, no erythema, no scarring, no blistering, and no crusts were observed. Mean subject satisfaction score was assessed and all volunteers reported to be "satisfied." CONCLUSIONS: The long pulsed high fluence alexandrite laser is effective and safe in the treatment of leg veins 0.3-1.3 mm in diameter.


Assuntos
Perna (Membro)/efeitos da radiação , Terapia com Luz de Baixa Intensidade/efeitos adversos , Transtornos da Pigmentação/etiologia , Telangiectasia/radioterapia , Adulto , Feminino , Seguimentos , Humanos , Perna (Membro)/patologia , Pessoa de Meia-Idade , Satisfação do Paciente , Transtornos da Pigmentação/patologia , Índice de Gravidade de Doença , Pele/patologia , Pele/efeitos da radiação , Telangiectasia/patologia , Fatores de Tempo , Resultado do Tratamento
20.
Lasers Surg Med ; 31(4): 257-62, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12355571

RESUMO

BACKGROUND AND OBJECTIVES: Untreated varicose veins have significant morbidity and potential mortality. Treatment aims to relieve symptoms, improve appearance, and to prevent deterioration. Current therapeutic options include graduated compression stockings, sclerotherapy, ambulatory phlebectomy, surgical ligation, and stripping. Results of laser photocoagulation of vascular anomalies have been encouraging. Applying these concepts of laser-tissue interactions, we developed a new method of treatment for varicose veins of the lower extremities. STUDY DESIGN/MATERIALS AND METHODS: One hundred and forty-nine patients with 252 varicose greater saphenous veins underwent endovenous laser photocoagulation (EVLP) from January 1996 to January 2000. Subject's age ranged between 23 years 9 months and 80 years 7 months with a mean age of 50 years 8 months. There were 122 females and 27 males. Only patients with primary varicose veins and saphenofemoral reflux documented by Duplex ultrasound were treated. All patients received surgical ligation of the saphenofemoral junction (SFJ). EVLP was performed using the neodymium:yttrium-aluminium-garnet (Nd:YAG) (1,064 nm) laser, delivered with a 600 microm optical fiber. Laser power was set at 10 or 15 W, delivered with a pulse duration of 10 seconds. The outcome was compared before and after EVLP, based on the score of severity of the varicose veins by Hach's classification. RESULTS: The range of total delivered energy is from 9,200 to 20,100 J. The entire procedure was completed in 95-175 minutes (mean 122.33 minutes) for bilateral procedures, and 65-100 minutes (mean 81.07 minutes) for unilateral procedures. The follow-up period ranged from 12 to 28 months with a mean of 19 months. One hundred and forty-one patients with 244 legs involved (96.8%) demonstrated remarkable improvement (P < 0.05). Common early complications of EVLP are: local paraesthesia of the treated area in 92 legs (36.5%), ecchymosis and dyschromia in 58 legs (23.0%), superficial burn injury in 12 legs (4.8%), superficial phlebitis in four legs (1.6%), and localized hematoma in two legs (0.8%) at 3 weeks post-operatively. The final outcome showed no significant morbidity or mortality. All patients recovered completely. CONCLUSIONS: EVLP is a simple effective treatment modality for varicose veins. This less invasive method can minimize the complications of conventional surgery.


Assuntos
Fotocoagulação a Laser/efeitos adversos , Fotocoagulação a Laser/métodos , Fotocoagulação/efeitos adversos , Fotocoagulação/métodos , Complicações Pós-Operatórias , Varizes/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Perna (Membro)/irrigação sanguínea , Perna (Membro)/patologia , Perna (Membro)/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Fatores de Tempo , Varizes/patologia
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