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1.
J Radiol Prot ; 44(2)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38722292

RESUMO

According to International Commission of Radiological Protection, the equivalent dose limit for the eye lens for occupational exposure is recommended to be 20 mSv yr-1, averaged over 5 years, with no single year above 50 mSv. Some studies reported the measurement of assistant's lens exposure in diagnostic computed tomography (CT) examinations, but further investigation is still required in the association between the lens dose for assistants and various dose parameters. Therefore, we measured the assistant's lens exposure using small optically stimulated luminescence dosimeters. The type of occupation, type of assistance, total scan time, total mAs, total scan length, and dose-length product (DLP) were recorded and analyzed in association with air kerma at the lens position. The assistance was classified into four types: 'assisted ventilation,' 'head holding,' 'body holding,' and 'raising patient's arm.' The air kerma of lens position was not significantly different for each assistance type (p< 0.05, Kruskal-Wallis test). Further, the lens doses for assistants correlated with DLP, but with various strengths of correlation with the assistance type and were influenced by the distance from the CT gantry. In conclusion, lens dose during assistance and DLP demonstrated the strongest correlation. 'Raising patient's arm' and 'head holding' exhibited stronger correlations, which required less table movement during the CT scan than 'assisted ventilation' and 'body holding'.


Assuntos
Cristalino , Exposição Ocupacional , Doses de Radiação , Tomografia Computadorizada por Raios X , Cristalino/efeitos da radiação , Humanos , Exposição Ocupacional/análise , Proteção Radiológica , Exposição à Radiação/análise
2.
J Radiol Prot ; 42(2)2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35705067

RESUMO

In computed tomography (CT) examinations, the usefulness of protective glasses for reducing lens exposure to assistants has been reported. The present study aimed to compare the dose reduction effect for assistants with lead-acrylic shields and protective glasses (0.07 mm Pb, 0.5 mm Pb) during CT examination. The air dose distribution in a CT examination room with and without a lead-acrylic shield was compared. It was found that the amount of scattered radiation was significantly reduced by installing a lead-acrylic shield at the CT gantry aperture. Moreover, the reduction rate of air kerma at the assistant's lens was higher using the lead acrylic shield than with the protective glasses-95.7% during head holding and 76.1% during assisted ventilation.


Assuntos
Cristalino , Proteção Radiológica , Chumbo , Imagens de Fantasmas , Doses de Radiação , Proteção Radiológica/métodos , Tomografia Computadorizada por Raios X , Raios X
3.
Hepatol Res ; 50(9): 1032-1046, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32602214

RESUMO

AIM: The underlying mechanism of non-obese non-alcoholic fatty liver disease (NAFLD) has not been fully elucidated. We classified patients with NAFLD by sex and body mass index and compared their clinical features to clarify the background pathophysiology of non-obese NAFLD. METHODS: A total of 404 patients with NAFLD were divided according to their body mass index (<25 [non-obese], 25 to <30 [obese], and ≥30 [severe obese]), and were further compared with 253 patients without obesity and NAFLD (non-NAFLD). RESULTS: The proportion of the individuals with non-obese NAFLD was 25.7% in men and 27.6% in women. The male and female non-obese NAFLD groups had lower skeletal muscle mass and muscle strength than the obese NAFLD groups. The visceral fat area, although low, was ≥100 cm2 in 59.3% of men and 43.8% of women. An increase in liver fat accumulation, hepatic fibrosis, homeostasis model assessment of insulin resistance, and leptin levels was modest in the non-obese NAFLD group compared with a marked increase in the obese NAFLD groups. The muscle mass of the non-obese NAFLD group was similar to that of the non-NAFLD group, but muscle steatosis was particularly common among women. Multivariate analysis revealed that the factors contributing to increased liver fat accumulation in the non-obese NAFLD group were visceral fat area, HbA1c, myostatin, and leptin. CONCLUSIONS: In patients with non-obese NAFLD, a sex difference was observed in the clinical features. In addition to increased visceral fat, decreased muscle mass and muscle strength, muscle atrophy (presarcopenia), and impaired glucose tolerance were considered to be important pathophysiological factors.

4.
Clin Exp Hypertens ; 42(4): 302-308, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-31392903

RESUMO

Intramyocellular lipid (IMCL) and extramyocellular lipid (EMCL) of ectopic fat in muscles are associated with arterial stiffness in normal-weight individuals. Furthermore, aerobic exercise training-induced changes in IMCL or EMCL content are related to a decrease in arterial stiffness in elderly people. Though arterial stiffness is strongly related with obesity, but the effects of aerobic exercise training on IMCL or EMCL content, with a particular focus on arterial stiffness, in obese individuals remains unclear. Here, we investigated the effects of aerobic exercise training on IMCL or EMCL content and arterial stiffness in obese individuals. First, in a cross-sectional study, we examined the relationship between arterial stiffness and IMCL or EMCL content in 24 overweight and obese men. Secondly, we investigated the effects of aerobic exercise intervention on arterial stiffness and IMCL or EMCL content in 21 overweight and obese men. In the cross-sectional study, EMCL content was positively correlated with baPWV and ß-stiffness index, whereas IMCL content was negatively correlated with baPWV. In the intervention study, there were no significant changes in baPWV, ß-stiffness index, and IMCL and EMCL contents after aerobic exercise training. However, exercise-induced change in baPWV and ß-stiffness index were positively correlated with changes in EMCL content. Moreover, the group of improvements in baPWV was only correlated significantly with reduced EMCL content. These results suggest that IMCL and EMCL contents may affect arterial stiffness in overweight and obese men.


Assuntos
Exercício Físico/fisiologia , Hipertensão , Metabolismo dos Lipídeos/fisiologia , Obesidade , Rigidez Vascular/fisiologia , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Hipertensão/prevenção & controle , Masculino , Pessoa de Meia-Idade , Obesidade/diagnóstico , Obesidade/metabolismo , Obesidade/fisiopatologia
7.
J Physiol Anthropol ; 43(1): 8, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310267

RESUMO

BACKGROUND: The concept of metabolically obese, normal weight (MONW) has emerged to describe individuals with a normal body mass index (BMI) who are at a relatively high risk of chronic diseases. However, BMI itself is a suboptimal index for the assessment of the health risks associated with visceral fat. The triglyceride-glucose (TyG) index is considered to be a reliable and cost-effective marker of insulin resistance. Therefore, in the present study, we aimed to determine the TyG index cut-off values that could be used to define MONW in older people and to determine the usefulness of these values for the prediction of chronic diseases. METHODS: A total of 4,721 participants in the Korea National Health and Nutritional Examination Survey who were ≥ 60 years of age and did not have underweight or obesity were included. MONW was defined using the criteria for metabolic syndrome (MS), and the TyG index was calculated on the basis of the fasting plasma triglyceride and glucose concentrations. Chronic diseases, including T2DM, hypertension, and non-alcoholic fatty liver disease (NAFLD), were diagnosed. RESULTS: The prevalence of MS increased from the lowest to the highest TyG index tertile. The cut-off values of the TyG index for MONW were calculated as 8.88 and 8.80 for males and females, respectively. MONW, defined using these cut-off values, was associated with high odds ratios for NAFLD, T2DM, and hypertension in both males and females. CONCLUSIONS: The TyG index cut-off values calculated in the present study can be used to discriminate individuals with MONW from other older individuals without obesity and to predict the risk of chronic diseases. These findings show that the TyG index is an effective and cost-efficient method of assessing the risk of chronic diseases in people with MONW.


Assuntos
Diabetes Mellitus Tipo 2 , Hipertensão , Síndrome Metabólica , Hepatopatia Gordurosa não Alcoólica , Masculino , Feminino , Humanos , Idoso , Peso Corporal , Triglicerídeos , Glucose , Índice de Massa Corporal , Hepatopatia Gordurosa não Alcoólica/complicações , Obesidade/epidemiologia , Síndrome Metabólica/epidemiologia , Glicemia , Diabetes Mellitus Tipo 2/complicações , Doença Crônica
8.
J Obes Metab Syndr ; 33(2): 143-154, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38735655

RESUMO

Background: Muscle-liver crosstalk plays an important role in the development and progression of non-alcoholic fatty liver disease (NAFLD). The measurement of muscle echo-intensity during ultrasonography is a real-time, non-invasive method of assessing muscle quality. In this retrospective study, we investigated the significance of poor muscle quality (namely, a greater mass of non-contractile tissue, including intramuscular fat) as a risk factor for advanced liver fibrosis and considered whether it may represent a useful tool for the diagnosis of advanced liver fibrosis. Methods: We analyzed data from 307 patients with NAFLD (143 men and 164 women) who visited the University of Tsukuba Hospital between 2017 and 2022. The patients were stratified into the following tertiles of muscle quality according to their muscle echo-intensity on ultrasonography: modest (84.1 arbitrary units [A.U.]), intermediate (97.4 A.U.), and poor (113.6 A.U.). We then investigated the relationships between muscle quality and risk factors for advanced liver fibrosis and calculated appropriate cutoff values. Results: Patients with poor muscle quality showed a significant, 7.6-fold greater risk of liver fibrosis compared to those with modest muscle quality. Receiver operating characteristic curve analysis showed that muscle quality assessment was as accurate as the fibrosis-4 index and NAFLD fibrosis score in screening for liver fibrosis and superior to the assessment of muscle quantity and strength, respectively. Importantly, a muscle echo-intensity of ≥92.4 A.U. may represent a useful marker of advanced liver fibrosis. Conclusion: Muscle quality may represent a useful means of identifying advanced liver fibrosis, and its assessment may become a useful screening tool in daily practice.

9.
Nutrients ; 15(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36771263

RESUMO

PURPOSE: This population-based cross-sectional study aimed to determine whether the triglyceride-glucose index (TyG index) is associated with sarcopenic obesity (SO) and whether it would be a helpful indicator of SO. METHODS: A total of 3821 participants aged ≥ 60 years were selected for the study group, and 4919 participants aged 20-39 years were included as a reference group. The participants were allocated to sarcopenia, obesity, and SO groups depending on if their body mass index (BMI) was ≥25 kg/m2 and their sarcopenia index was ≤1 standard deviation (SD) lower than the mean of the reference group. The sex-specific differences and trends among the participants were analyzed by using the TyG index tertiles, and appropriate cut-off values of the TyG index for SO were calculated. RESULTS: As the TyG index increased, BMI increased, but the sarcopenia index decreased in both sexes. Males and females in the middle and highest tertiles of the TyG index were 1.775 and 3.369, and they were 1.993 and 3.157 times more likely to have SO, respectively. The cut-off values of the TyG index for SO in males and females were ≥8.72 and 8.67, respectively. CONCLUSION: A high TyG index is positively associated with SO, and the TyG index may be considered a potential indicator of SO.


Assuntos
Resistência à Insulina , Sarcopenia , Masculino , Feminino , Humanos , Idoso , Glucose , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Triglicerídeos , Fatores de Risco , Estudos Transversais , Glicemia , Obesidade/complicações , Biomarcadores
10.
Nutrients ; 15(12)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37375668

RESUMO

The incidence of non-obese non-alcoholic fatty liver disease (NAFLD), characterized by the presence of a fatty liver in individuals with a normal body mass index, is on the rise globally. Effective management strategies, including lifestyle interventions such as diet and exercise therapy, are urgently needed to address this growing public health concern. The aim of this study was to investigate the association between non-obese NAFLD, dietary habits, and physical activity levels. By elucidating these relationships, this research may contribute to the development of evidence-based recommendations for the management of non-obese NAFLD. The study had a single-center retrospective cross-sectional design and compared clinical data and dietary and physical activity habits between patients with and without non-obese NAFLD. Logistic regression analysis was utilized to investigate the relationship between food intake frequency and the development of NAFLD. Among the 455 patients who visited the clinic during the study period, 169 were selected for analysis, including 74 with non-obese NAFLD and 95 without NAFLD. The non-obese NAFLD group showed a less-frequent consumption of fish and fish products as well as olive oil and canola/rapeseed oil, while they showed more frequent consumption of pastries and cake, snack foods and fried sweets, candy and caramels, salty foods, and pickles compared to the non-NAFLD group. Logistic regression analysis revealed that NAFLD was significantly associated with the consumption of fish, fish products, and pickles at least four times a week. The physical activity level was lower and the exercise frequency was lower in patients with non-obese NAFLD compared to those without NAFLD. The results of this study suggest that a low consumption of fish and fish products and high consumption of pickles may be associated with a higher risk of non-obese NAFLD. Moreover, dietary habits and physical activity status should be taken into consideration for the management of patients with non-obese NAFLD. It is important to develop effective management strategies, such as dietary and exercise interventions, to prevent and treat NAFLD in this patient population.


Assuntos
Dieta , Exercício Físico , Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Estudos Transversais , População do Leste Asiático , Comportamento Alimentar , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Estudos Retrospectivos , Fatores de Risco
11.
J Med Radiat Sci ; 70(2): 154-160, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36811316

RESUMO

INTRODUCTION: Despite the development of DOSIRIS™, an eye lens dosimeter, the characteristics of DOSIRIS™ in the area of radiotherapy have not been investigated. The purpose of this study was to evaluate the basic characteristics of the 3-mm dose equivalent measuring instrument DOSIRIS™ in radiotherapy. METHODS: Dose linearity and energy dependence were evaluated for the irradiation system based on the calibration method of the monitor dosimeter. The angle dependence was measured by irradiating from a total of 18 directions. Interdevice variation was repeated three times by simultaneously irradiating five dosimeters. The measurement accuracy was based on the absorbed dose measured by the monitor dosimeter of the radiotherapy equipment. Absorbed doses were converted to 3-mm dose equivalents and compared with DOSIRIS™ measurements. RESULTS: Dose linearity was evaluated using the determination coefficient (R2 ) R2  = 0.9998 and 0.9996 at 6 and 10 MV, respectively. For energy dependence, although the therapeutic photons evaluated in this study had higher energies than in the previous studies and had a continuous spectrum, the response was equivalent to 0.2-1.25 MeV, well below the IEC 62387 limits. The maximum error at all angles was 15% (angle of 140°) and the coefficient of variation at all angles was 4.70%, which satisfies the standard of the thermoluminescent dosimeter measuring instrument. Accuracy of measurement was determined in terms of the measurement errors for DOSIRIS™ (3.2% and 4.3% at 6 and 10 MV, respectively,) using the 3-mm dose equivalent obtained from the theoretical value as a reference. The DOSIRIS™ measurements met the IEC standard which defines the measurement error of ±30% of the irradiance value in IEC 62387. CONCLUSIONS: We found that the characteristics of the 3-mm dose equivalent dosimeter in a high-energy radiation satisfy the IEC standards and have the same measurement accuracy as diagnostic areas such as Interventional Radiology.


Assuntos
Cristalino , Radiometria , Cristalino/efeitos da radiação , Calibragem
12.
Artigo em Inglês | MEDLINE | ID: mdl-36981616

RESUMO

Because obesity is associated with impaired glucose tolerance and type 2 diabetes (T2D), it is important to manage the blood glucose level at an early stage. Nevertheless, people with obesity have significantly lower resistance to muscle fatigue after exercise and exercise adherence. Therefore, we developed a novel "Relaxing-Vibration Training (RVT)" consisting of 25 postures using vibration stimulation of skeletal muscle and determined the feasibility of RVT for glycemic management. Thirty-one participants with obesity were enrolled in a controlled trial (CT) and experimental trial (ET) based on a 75 g oral glucose tolerance test (OGTT). During the CT, participants were required to rest in a quiet room. During the ET, the RVT program (50 Hz, 4 mm), consisting of 25 postures of relaxation and stretching on the vibratory platform, was performed for 40 min. Subsequently, the participants rested as in the CT. Subjective fatigue and muscle stiffness measurements and blood collection were conducted before and after RVT. In both the CT and ET, interstitial fluid (ISF) glucose concentrations were measured every 15 min for 2 h. The incremental area under the curve value of real-time ISF glucose during an OGTT was significantly lower in the ET than in the CT (ET: 7476.5 ± 2974.9, CT: 8078.5 ± 3077.7, effect size r = 0.4). Additionally, the levels of metabolic glucose regulators associated with myokines, muscle stiffness, and subjective fatigue significantly improved after RVT. This novel RVT suggests that it is effective in glycemic management with great potential to improve impaired glucose tolerance and T2D with obesity in the future.


Assuntos
Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Humanos , Glicemia/metabolismo , Glucose/metabolismo , Músculo Esquelético/metabolismo , Obesidade/terapia , Obesidade/metabolismo , Vibração/uso terapêutico
13.
J Contemp Brachytherapy ; 15(5): 357-364, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38026071

RESUMO

Purpose: Several cases of inaccurate irradiation in brachytherapy have been reported, occurring similarly to external radiation. Due to a large dose per fraction in brachytherapy, inaccurate irradiation can seriously harm a patient. Although various studies have been conducted, systems that detect inaccurate irradiation in brachytherapy are not as developed as those for external irradiation. This study aimed to construct a system that analyzes the source dwell position during irradiation using computed tomography (CT) scout images. The novelty of the study was that by using CT scout images, high versatility and analysis of absolute coordinates can be achieved. Material and methods: A treatment plan was designed with an iridium-192 (192Ir) source delivering radiation at two dwell positions in a tandem applicator. CT scout images were taken during irradiation, and acquired under different imaging conditions and applicator geometries. First, we confirmed whether a source was visible in CT scout images. Then, employing in-house MATLAB program, source dwell coordinates were analyzed using the images. An analysis was considered adequate when the resulting source dwell coordinates agreed with the treatment plan within ±1 mm, in accordance with AAPM TG56 guidelines for source dwell position accuracy. Results: The source dwelling was visible in CT scout image, which was enlarged or reduced depending on applicator geometries. The applicator was enlarged by 127% when 130 mm away from the center of CT gantry. The analysis results using our in-house program were considered adequate; although, analysis parameters required adjustments depending on imaging conditions. Conclusions: The proposed system can be easily implemented for image-guided brachytherapy and can analyze the absolute coordinates of source dwell position. Therefore, the system could be used for preventing inaccurate irradiation by verifying whether brachytherapy was performed properly.

14.
Artigo em Japonês | MEDLINE | ID: mdl-23001272

RESUMO

The fractional anisotropy (FA) is calculated by using diffusion tensor imaging (DTI) with multiple motion probing gradients (MPG). While FA has become a widely used tool to detect moderate changes in water diffusion in brain tissue, the measured value is sensitive to scan parameters (e.g. MPG-direction, signal to noise ratio, etc.). Therefore, it is paramount to address the reproducibility of DTI measurements among multiple centers. The purpose of this study was to assess the inter-center variability of FA. We studied five healthy volunteers who underwent DTI brain scanning three times at three different centers (I-III), each with a 1.5 T scanner having a different MPG-schema. Then, we compared the FA and eigenvalue from the three centers measured in seven brain regions: splenium of corpus callosum (CCs), genu of corpus callosum (CCg), putamen, posterior limb of internal capsule, cerebral peduncle, optic radiation, and middle cerebellar peduncle. At the CCs and CCg, there was a statistical difference (p<0.05) between center Iand center IIfor the same MPG-directions. Furthermore, at CCs and CCg, there was a statistical difference (p<0.05) between center II and center III for different MPG-directions. Conversely, no statistical differences were found between center I and center III for the different MPG-directions for all regions. These results indicate that the FA value was affected by the MPG-schema as well as by the MPG-directions.


Assuntos
Anisotropia , Encéfalo , Imagem de Tensor de Difusão/métodos , Corpo Caloso , Humanos , Cápsula Interna , Putamen , Reprodutibilidade dos Testes , Tegmento Mesencefálico
15.
Artigo em Inglês | MEDLINE | ID: mdl-35457793

RESUMO

A body shape index (ABSI) is a recently introduced index of abdominal adiposity, relative to body mass index and height, and represents an alternative to body mass index and waist circumference. We aimed to determine whether ABSI is associated with osteoporosis and the ability of ABSI to predict osteoporosis, to investigate the relationship between obesity and osteoporosis In total, 6717 Korean participants (3151 men and 3566 women; 63.6 ± 8.5 years) were recruited and placed into the Normal, Osteopenia, or Osteoporosis groups on the basis of the minimum T-scores of the lumbar spine, proximal femur, and femoral neck. The T-scores of each region and ABSI were compared among the groups and odds ratios and cut-off values of ABSI for osteoporosis were calculated. In participants of both sexes, ABSI tended to increase as bone health deteriorated. The men and women in the highest quartile of ABSI were 1.887 and 2.808 times more likely to have osteoporosis, respectively, and the potential ABSI cut-off values for osteoporosis were 0.0813 and 0.0874 for male and female participants, respectively. These findings suggest that augmentation of ABSI and obesity is associated with a higher risk of osteoporosis and that ABSI may predict the risk of osteoporosis.


Assuntos
Obesidade , Osteoporose , Idoso , Antropometria , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Osteoporose/complicações , Osteoporose/epidemiologia , República da Coreia/epidemiologia , Fatores de Risco , Circunferência da Cintura
16.
Radiother Oncol ; 171: 146-154, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35461953

RESUMO

BACKGROUND AND PURPOSE: The technique of gating near end-exhalation is commonly adopted to reduce respiration-associated geometric uncertainties for particle beam therapy. However, for irradiation fields involving the liver dome, how diaphragm movements generating liver-lung interface change, alongside geometric uncertainties, remain unspecified. METHODS AND MATERIALS: Patients receiving respiratory-gated computed tomography (RGCT) with four-dimensional computed tomography (4DCT) scans during simulation were retrospectively reviewed. Differences (Δ) between RGCT and 4DCT images, including diaphragm displacements and liver-lung interface changes, were investigated to specify geometric uncertainties during early inhalation phases. Craniocaudal displacements (Δy, in sagittal/coronal planes) of diaphragm segments (dorsal/ventral/right lateral/medial), liver area changes (ΔA, in axial planes), and liver extent changes in specific directions of incidence (Δr, in axial planes) were analyzed. RESULTS: Altogether, 162 patients received simulating RGCT and 4DCT scans. In 22 of them, both images involved the liver dome. For most cases during early inhalation phases, the Δy values in the dorsal diaphragm were significantly greater than those in the ventral diaphragm (p < 0.05), the ΔA values were significantly enlarged with inhalation progressing (p < 0.05), and the Δr values in the dorsal direction were significantly larger than those in the ventral direction (p < 0.05). These results suggested that the dorsal diaphragm moves earlier and more in a caudal direction than the ventral diaphragm during early inhalation phases. CONCLUSIONS: For respiratory-gated radiotherapy near end-exhalation and irradiation fields involving the liver dome, components of geometric uncertainties are temporospatial, including diaphragm segment movements, inhalation phases of irradiation, and beam angles of incidence.


Assuntos
Expiração , Neoplasias Pulmonares , Diafragma/diagnóstico por imagem , Tomografia Computadorizada Quadridimensional/métodos , Humanos , Fígado/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Movimento , Respiração , Estudos Retrospectivos
17.
Jpn J Radiol ; 40(5): 525-533, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34779984

RESUMO

PURPOSE: To evaluate the outcomes of particle therapy in cancer patients with cardiac implantable electronic devices (CIEDs). MATERIALS AND METHODS: From April 2001 to March 2013, 19,585 patients were treated with proton beam therapy (PBT) or carbon ion therapy (CIT) at 8 institutions. Of these, 69 patients (0.4%, PBT 46, CIT 22, and PBT + CIT 1) with CIEDs (64 pacemakers, 4 implantable cardioverter defibrillators, and 1 with a cardiac resynchronization therapy defibrillator) were retrospectively reviewed. All the patients with CIEDs in this study were treated with the passive scattering type of particle beam therapy. RESULTS: Six (13%) of the 47 PBT patients, and none of the 23 CIT patients experienced CIED malfunctions (p = 0.105). Electrical resets (7) and over-sensing (3) occurred transiently in 6 patients. The distance between the edge of the irradiation field and the CIED was not associated with the incidence of malfunctions in 20 patients with lung cancer. A larger field size had a higher event rate but the test to evaluate trends as not statistically significant (p = 0.196). CONCLUSION: Differences in the frequency of occurrence of device malfunctions for patients treated with PBT and patients treated with CIT did not reach statistical significance. The present study can be regarded as a benchmark study about the incidence of malfunctioning of CIED in passive scattering particle beam therapy and can be used as a reference for active scanning particle beam therapy.


Assuntos
Neoplasias , Marca-Passo Artificial , Carbono/uso terapêutico , Eletrônica , Humanos , Neoplasias/radioterapia , Prótons , Estudos Retrospectivos
18.
No Shinkei Geka ; 39(5): 485-90, 2011 May.
Artigo em Japonês | MEDLINE | ID: mdl-21512199

RESUMO

We report a case, in which quantitative 1H-MR spectroscopy (MRS) was useful for the differentiation between radiation necrosis and a recurrent tumor. The present case is a 44-year-old man who underwent the subtotal removal of a mass lesion in the left frontal lobe. The histological diagnosis was anaplastic oligodendroglioma (WHO grade III). Postoperatively, a fractionated radiotherapy (total 64Gy) and chemotherapy were performed. MRI after the radiotherapy showed no contrast enhancing lesion. MRI, 5 years after the radiotherapy, showed a growing enhancing lesion and a T1 hypointensity lesion without enhancement, both of which indicated a recurrent tumor. MR spectroscopy was performed for the differential diagnosis of these lesions. The spectrum was acquired by the point resolved spectroscopy (PRESS) method by TR/TE=2,000 ms/68 ms, 136 ms, and 272 ms and evaluated with peak pattern and quantification value of metabolite. MRS of the enhancing lesion demonstrated a decrease of the Choline-containing compounds (Cho) concentration, disappearance of N-acetylaspartate (NAA), decrease of Creatine/ Phosphocreatine (t-Cr) and presence of Lipids (Lip) and Lactate (Lac), all of which are characteristic finding of a radiation necrosis. The histological diagnosis of this lesion showed evidence also of radiation necrosis. On the other hand, MRS of the T1 hypointensity lesion without enhancement showed, a marked high peak of the Cho concentration, which is characteristic for a recurrent tumor. The histological findings of this lesion showed a diffuse proliferation of recurrent tumor cells. Quantitative 1H-MRS is a useful tool for the differentiation between radiation necrosis and recurrent tumors.


Assuntos
Encefalopatias/diagnóstico , Neoplasias Encefálicas/diagnóstico , Lobo Frontal , Espectroscopia de Ressonância Magnética , Recidiva Local de Neoplasia/diagnóstico , Oligodendroglioma/diagnóstico , Lesões por Radiação/diagnóstico , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análise , Encefalopatias/patologia , Colina/análise , Creatina/análise , Diagnóstico Diferencial , Humanos , Lactatos/análise , Lipídeos/análise , Masculino , Necrose , Oligodendroglioma/radioterapia , Fosfocreatina/análise
19.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 28(6): 1103-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22295694

RESUMO

This study was aimed to explore the value of quantitative proton MR spectroscopy (1H-MRS) in the differentiation of benign and malignant meningioma. 23 cases, including 19 benign (grade I) and 4 malignant (grade II-III) meningiomas, underwent single voxel 1H-MRS (TR/TE = 2000 ms/68, 136, 272 ms). T2 relaxation time of tissue water and choline were estimated by an exponential decay model. Choline concentration was calculated using tissue water as the internal reference, and corrected according to intra-voxel cystic/necrotic parts. Tissue water T2 of benign and malignant meningiomas were (105 +/- 41) ms and (151 +/- 42) ms, respectively. The difference was statistically significant (P = 0.033). While Choline T2 of benign and malignant meningiomas were (242 +/- 73) ms and (316 +/- 102) ms respectively, the difference was not significant (P = 0.105). Choline concentration was (2.86 +/- 0.86) mmol/ kg wet weight in benign meningiomas and (3.53 +/- 0.60) mmol/kg wet weight in malignant ones; after correction they increased to (2.98 +/- 0.93)mmol/kg wet weight and (4.58 +/- 1.22) mmol/kg wet weight, respectively, and the difference was significant (P = 0.019). In conclusion, quantitative 1H-MRS is useful for the differentiation of benign and malignant meningioma by T2 relaxation time and absolute choline concentration.


Assuntos
Colina/metabolismo , Espectroscopia de Ressonância Magnética , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Neoplasias Meníngeas/metabolismo , Neoplasias Meníngeas/patologia , Meningioma/metabolismo , Meningioma/patologia , Pessoa de Meia-Idade , Prótons , Adulto Jovem
20.
Artigo em Inglês | MEDLINE | ID: mdl-34948483

RESUMO

The A Body Shape Index (ABSI) was recently introduced to quantify abdominal adiposity relative to the body mass index (BMI) and height. This cross-sectional study was performed to explore whether the ABSI is linked to chronic kidney disease (CKD) in older adults and compare the predictive capacity of the ABSI versus BMI for CKD. In total, 7053 people aged ≥ 60 years were divided into normal, mild, and moderate-to-severe CKD groups based on their estimated glomerular filtration rate (eGFR). The correlation of the ABSI with the eGFR and the differences and trends in the ABSI and BMI among the groups were analyzed, and the cutoff points for moderate-to-severe CKD were calculated. The association between the ABSI and CKD was stronger than that between the BMI and CKD. The ABSI had a better capacity to discriminate the CKD stage than did the BMI. The capacity of the ABSI to predict moderate-to-severe CKD was higher than that of the BMI and was more substantial in women than men. The ABSI cutoff points for CKD were ≥0.0822 and 0.0795 in men and women, respectively. In conclusion, the ABSI serves as a better index than the BMI for screening and detecting high-risk individuals with CKD.


Assuntos
Obesidade , Insuficiência Renal Crônica , Idoso , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Masculino , Obesidade Abdominal , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Fatores de Risco , Circunferência da Cintura
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