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1.
JACC Cardiovasc Imaging ; 17(1): 45-58, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37452820

RESUMO

BACKGROUND: Fluorodeoxyglucose positron emission tomography (18F-FDG-PET) can noninvasively assess active inflammatory myocardium in patients with cardiac sarcoidosis (CS). Prednisolone (PSL) is the initial drug of choice for active CS; however, its efficacy has not been prospectively evaluated. Moreover, there are no alternative systematic treatment strategies. OBJECTIVES: The goal of this study was to evaluate the efficacy of methotrexate (MTX) in patients refractory to PSL assessed by using cardiac metabolic activity (CMA) in 18F-FDG-PET. METHODS: A total of 59 patients with active CS were prospectively enrolled. CMA (standardized uptake value × accumulation area) was used as an indicator of active inflammation, and a 6-month regimen of PSL therapy was introduced, followed by a second FDG scan. Poor responders to PSL therapy (CMA reduction rate <70%) and patients with recurrent CS (CMA reduction rate ≥70% after initial PSL therapy but CMA recurred after an additional 6 months of therapy) were randomly assigned to the MTX or repeat PSL (re-PSL) therapy groups for another 6 months. RESULTS: Fifty-six patients completed the initial 6-month PSL therapy regimen. Median CMA reduced from 203.3 to 1.0 (P < 0.001), and 47 patients were allocated to the response group, 9 to the poor response group, and 2 to the recurrent group. Accordingly, 11 patients were randomly assigned to the MTX (n = 5) or re-PSL (n = 6) groups. After 6 months, neither group showed a significant reduction in CMA values. MTX was comparable to re-PSL in reducing CMA. CONCLUSIONS: The 6-month regimen of PSL was a potent therapeutic tool for active CS. When MTX was added to low-dose PSL in patients refractory to the initial PSL therapy, there was no significant difference compared with re-PSL. Further studies are needed to evaluate the therapeutic potential of MTX for active CS, including how MTX works when it is administered in higher doses or for longer periods.


Assuntos
Cardiomiopatias , Miocardite , Sarcoidose , Humanos , Fluordesoxiglucose F18 , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/tratamento farmacológico , Compostos Radiofarmacêuticos , Valor Preditivo dos Testes , Miocárdio/metabolismo , Sarcoidose/diagnóstico por imagem , Sarcoidose/tratamento farmacológico , Sarcoidose/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Terapia de Imunossupressão
2.
J Acoust Soc Am ; 133(2): 1169-86, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23363133

RESUMO

While occupational injury is associated with numerous individual and work-related risk factors, including long working hours and short sleep duration, the complex mechanisms causing such injuries are not yet fully understood. The relationship between the infrasound pressures of the tympanic membrane [ear canal pressure (ECP)], detected using an earplug embedded with a low-frequency microphone, and the carotid artery [carotid artery pressure (CAP)], detected using a stethoscope fitted with the same microphone, can be quantitatively characterized using systems analysis. The transfer functions of 40 normal workers (19 to 57 years old) were characterized, involving the analysis of 446 data points. The ECP waveform exhibits a pulsatile character with a slow respiratory component, which is superimposed on a biphasic recording that is synchronous with the cardiac cycle. The respiratory ECP waveform correlates with the instantaneous heart rate. The results also revealed that various fatigue-related risk factors may affect the mean magnitudes of the measured pressures and the delay transfer functions between CAP and ECP in the study population; these factors include systolic blood pressure, salivary amylase activity, age, sleep duration, postural changes, chronic fatigue, and pulse rate.


Assuntos
Pressão Arterial , Artérias Carótidas/fisiologia , Membrana Timpânica/fisiologia , Adulto , Pressão Atmosférica , Análise Discriminante , Feminino , Análise de Fourier , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Doenças Profissionais/etiologia , Doenças Profissionais/fisiopatologia , Postura , Análise de Regressão , Taxa Respiratória , Fatores de Risco , Estetoscópios , Fatores de Tempo , Transdutores de Pressão , Adulto Jovem
3.
Sci Rep ; 8(1): 10976, 2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-30030499

RESUMO

Ra-223 has recently been introduced to alpha radionuclide therapy. According to the decay scheme of Ra-223, an inert gas, Rn-219 is released from patients during alpha radionuclide therapy and its daughter radionuclides may accumulate around the patient. However, the concentration of these radon daughters during alpha radionuclide therapy was not obvious. Here, we first detected the radon daughters of Rn-219 around patients during alpha radionuclide therapy. While the Ra-223-administered patients were in a room for ~1.5 hours, the radon daughter concentration increased to 4 to 5 times higher than without the patients. When the patients were in the room, the energy spectra of the alpha particles in the air showed the peak of the radon daughter of Rn-219, Bi-211 (6.6 MeV), which was different from that without the patients. We conclude that the daughter radionuclides of Rn-219 are accumulated around the patient, and the concentration was higher than that of the natural radon daughters. However, the increase in levels of alpha emitters, while detectable, is lower than the daily variations and thus is likely not a source of concern for radiation exposure.


Assuntos
Poluentes Radioativos do Ar/análise , Partículas alfa/efeitos adversos , Radioterapia/efeitos adversos , Rádio (Elemento)/uso terapêutico , Partículas alfa/uso terapêutico , Humanos , Exposição à Radiação , Rádio (Elemento)/análise , Produtos de Decaimento de Radônio/análise
4.
Dement Geriatr Cogn Dis Extra ; 8(1): 85-97, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29706985

RESUMO

BACKGROUND: In this study, we examined the construct validity, concurrent validity concerning other standard scales, intrarater reliability, and changes in scores at 12 weeks of the previously developed ABC Dementia Scale (ABC-DS), a novel assessment tool for Alzheimer's disease (AD). METHODS: Data were obtained from 312 patients diagnosed with either AD or mild cognitive impairment. The scores on the ABC-DS and standard scales were compared. RESULTS: The 13 items of the ABC-DS are grouped into three domains, and the domain-level scores were highly correlated with the corresponding conventional scales. Statistically significant changes in assessment scores after 12 weeks were observed for the total ABC-DS scores. CONCLUSION: Our results demonstrate the ABC-DS to have good validity and reliability, and its usefulness in busy clinical settings.

5.
J Palliat Med ; 20(2): 177-180, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27672720

RESUMO

BACKGROUND/AIMS: The optimal regimen of radiotherapy (RT) for bleeding from gastric cancer (GC) has not yet been established. The aim of this study was to evaluate the usefulness of low-dose, short-course palliative RT (LSP-RT) for bleeding from GC. MATERIAL AND METHODS: We reviewed the clinical data of 18 patients (26 courses) who received palliative RT for bleeding from GC between 2004 and 2014. The radiation dose was 6 Gy in three fractions. The total courses of RT for each patient were 1-4 (median, 1). RESULTS: The treatment success rate of the first and the additional RT at two weeks after RT was 55% and 75%, respectively. Regarding first RT, there was a statistically significant increase in the mean hemoglobin level for one month (p = 0.009) and a significant decrease in the mean number of transfused red blood cell units for one month (p = 0.012). Toxicities were observed in two patients: one patient who received chemotherapy developed grade 3 afebrile leukocytopenia and another who had a malignant stricture suffered from a gastric obstruction. The performance status was improved in 3 of the 12 evaluable patients (25%) and dietary intake became possible one month after RT in three of the four patients who had not been able to eat before RT. CONCLUSION: LSP-RT is expected to be not only an effective and safe treatment option for bleeding from GC, but also repeatable in cases of rebleeding. Furthermore, this treatment modality may be able to improve the patient's quality of life.


Assuntos
Hemorragia Gastrointestinal/radioterapia , Cuidados Paliativos/métodos , Doses de Radiação , Neoplasias Gástricas/radioterapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemostasia , Humanos , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Qualidade de Vida
6.
No Shinkei Geka ; 30(7): 735-9, 2002 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-12134670

RESUMO

The authors report the successful case of combined therapy using surgery and stereotactic radiosurgery for facial schwannoma in the middle cranial fossa, and discuss the surgical strategy for preservation of facial nerve function. This 27-year-old man presented with a 9-year history of right facial palsy and spasm. CT scan and MR imaging demonstrated a tumor 3 x 3 x 4 cm in size extending to the intradural middle cranial fossa from the petrous bone. After total removal of the intradural tumor, gamma knife radiosurgery was performed for residual tumor in the petrous bone. The marginal dose to the tumor was 12 Gy. Facial spasm disappeared, but facial palsy is unchanged 14 months after the radiosurgery.


Assuntos
Neoplasias dos Nervos Cranianos/cirurgia , Doenças do Nervo Facial/cirurgia , Neurilemoma/cirurgia , Radiocirurgia , Adulto , Neoplasias dos Nervos Cranianos/patologia , Doenças do Nervo Facial/patologia , Humanos , Masculino , Neurilemoma/patologia
7.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 59(5): 632-9, 2003 May.
Artigo em Japonês | MEDLINE | ID: mdl-12881694

RESUMO

To achieve quantitative accuracy of simultaneous emission/transmission (SET) acquisition using the mask technique, we determined the factor of expression that derives the true transmission data from the measured transmission and emission data. We then evaluated the standardized uptake value (SUV) of the regional activity concentration derived respectively from the SET scans and conventional scans. First, to determine the attenuation factor for the transmission source when the photons of the cylindrical phantom filled with (18)F solution reached emission memory, SET scans were performed with a dummy transmission source and under the blank status of the transmission source. Second, to evaluate the SUV, we used a hollow-sphere phantom filled with (18)F solution whose activity concentrations were approximately 3 and 5 times that of the background. Then we performed conventional and SET scans of the phantom for solutions ranging from the higher concentration to the lower concentration. All of the data were reconstructed with the decay correction, and the SUV of each sphere was derived. The results demonstrated that, when the conventional factor was used, SUV was underestimated according to the increasing activity concentration of the solution. However, when a new factor that took into account the attenuation of the transmission source was used, there was no significant difference in the SUV. We estimated the SUV derived from the SET scans was within 3% for the large spheres and within 16% for the small spheres.


Assuntos
Tomografia Computadorizada de Emissão/métodos , Radioisótopos de Flúor/farmacocinética , Fluordesoxiglucose F18/farmacocinética , Imagens de Fantasmas , Compostos Radiofarmacêuticos/farmacocinética
8.
Clin Nucl Med ; 37(3): 258-63, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22310252

RESUMO

OBJECTIVE: The conventional methods for the estimation of regional cerebral blood flow (rCBF) using ¹²³I-labeled N-isopropyl-p-iodoamphetamine (¹²³I IMP) autoradiography (ARG) require continuous or 1-point arterial blood sampling. Patients who need rCBF quantification benefit from the avoidance of arterial puncture. In this study, we attempted to develop a method without any blood sampling to estimate ¹²³I IMP activity in the arterial blood sample at 10 minutes after injection of ¹²³I IMP (Ca10) for the purpose of rCBF quantification. For the evaluation of validity of this method, the mean of rCBFs in various regions of the brain (mean CBF) calculated by ¹²³I IMP ARG method using the estimated Ca10 was compared with that calculated using the Ca10 directly measured with the actual arterial blood sample. Both groups of the mean CBF values were also compared with those measured by O-15 H2O PET ARG method. METHODS: I-123 IMP ARG study was applied to 23 patients, and O-15 H2O PET ARG was applied to 20 patients of them. Dynamic images of the lungs, time series of static images of the brain, and brain SPECT images were acquired after injection of ¹²³I IMP. Arterial blood sampling was done 10 minutes after injection of ¹²³I IMP. Multiple regression analysis was used to estimate Ca10 using 5 parameters from the lung washout counts, time series of brain static counts, and brain SPECT average counts as the explanatory variables and the Ca10 directly measured with the actual arterial blood sample as the objective variable, and the regression equation was calculated. RESULTS: The regression equation was calculated by multiple regression analysis as follows: Estimated Ca10 = (2.09 × 10⁻² · LW3) - (2.29 × 10⁻4 · Cb5) - (9.87 × 10⁻³ · Cbpre-SPECT) + (1.06 · CbSPECTav) + (1.03 × 10⁻² · Cbpost-SPECT) + 165 (counts/s/g), where LW3: lung washout count at 3 minutes after injection, Cb5: brain count at 5 minutes, Cb pre-SPECT: brain count before SPECT, Cb SPECT av: average brain count during SPECT, and Cb post-SPECT: brain count after SPECT. The estimated Ca10 values closely correlated with the directly measured Ca10 values (r = 0.907, P < 0.01). The mean CBF values (mL/min/100 g) calculated by ¹²³I IMP ARG method using the estimated Ca10 also closely correlated with those calculated using the directly measured Ca10 (r = 0.818, P < 0.01). The mean CBF values calculated by the ¹²³I IMP ARG method using either the directly measured or the estimated Ca10 significantly correlated (r = 0.698 and 0.590, respectively; P < 0.01) with those measured by O-15 H2O PET ARG method. CONCLUSIONS: The ¹²³I IMP arterial blood activity can be estimated reliably without any blood sampling using the ¹²³I IMP acquisition data from the lungs and brain. This method can serve for a convenient and noninvasive rCBF quantification technique instead of the conventional methods requiring arterial blood sampling.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Transtornos Cerebrovasculares/diagnóstico por imagem , Radioisótopos do Iodo , Iofetamina , Pulmão/irrigação sanguínea , Pulmão/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Autorradiografia/métodos , Transtornos Cerebrovasculares/fisiopatologia , Distribuição de Qui-Quadrado , Feminino , Humanos , Radioisótopos do Iodo/administração & dosagem , Radioisótopos do Iodo/farmacocinética , Iofetamina/administração & dosagem , Iofetamina/farmacocinética , Masculino , Pessoa de Meia-Idade , Radioisótopos de Oxigênio/administração & dosagem , Radioisótopos de Oxigênio/farmacocinética , Fluxo Sanguíneo Regional , Análise de Regressão
9.
Clin Nucl Med ; 37(9): 843-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22889772

RESUMO

PURPOSE: The aim of our study was to examine the usefulness of PET with C-methionine (MET) and F-fluorodeoxyglucose (FDG) in the differentiation of glioblastoma multiforme (GBM) and intracranial diffuse large B-cell lymphoma (DLBCL). MATERIALS AND METHODS: We evaluated 22 patients retrospectively with an enhancing brain tumor on MRI, including 15 GBM and 7 DLBCL, which was confirmed by histopathology. Dynamic PET scans with MET and FDG were performed for preoperative differential diagnosis. We assessed the images qualitatively and quantitatively. In quantitative assessment, the SUVmax was used on FDG PET and both late and early phases on MET PET. In addition, the ratio of SUVmax in the late and early phases on MET-PET was evaluated (ΔSUVmax). RESULTS: SUVmax on FDG PET of DLBCL was significantly higher than that of GBM. Setting an SUVmax of 12.0 as the cutoff for differentiating DLBCL from GBM, 1 GBM and 1 DLBCL were found to be false-positive and false-negative, respectively.SUVmax in the late and early phases of MET-PET was not significantly different between DLBCL and GBM; however, we also found significant differences in ΔSUVmax on MET-PET. Using ΔSUVmax 1.17 as the cutoff, we could differentiate DLBCL from GBM completely. In the present study, ΔSUVmax on MET-PET was slightly superior to SUVmax on FDG PET. CONCLUSIONS: Both SUVmax on FDG PET and ΔSUVmax on MET-PET were considered to be good diagnostic tests when encountering difficulties in this differential diagnosis.


Assuntos
Fluordesoxiglucose F18 , Glioblastoma/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Metionina , Tomografia por Emissão de Pósitrons , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Controle de Qualidade , Estudos Retrospectivos , Adulto Jovem
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