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1.
Radiat Prot Dosimetry ; 181(4): 333-342, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29506291

RESUMEN

The purpose of this study was to investigate a practical patient dose index for assessing the patient organ dose from a cone-beam computed tomography (CBCT) scan by comparing eight dose indices, i.e. CTDI100, CTDIIEC, CTDI∞, midpoint doses f(0)PMMA for a cylindrical polymethyl methacrylate (PMMA) phantom, f(0)Ap for an anthropomorphic phantom and f(0)Pat for a prostate cancer patient, as well as the conventional size specific dose estimations (SSDEconv) and modified SSDE (SSDEmod), with organ dose for the prostate (ODprost) obtained via Monte Carlo (MC) simulation. The ODprost was the reference dose used to find the practical dose index at the center of the pelvic region of a prostate cancer patient. The smallest error rate with respect to the ODprost of 19.3 mGy (reference) among eight dose indices was 5% for f(0)Pat. The practical patient dose index was the f(0)Pat, which showed the smallest error with respect to the reference dose.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/radioterapia , Dosis de Radiación , Humanos , Masculino , Método de Montecarlo , Órganos en Riesgo , Fantasmas de Imagen
2.
Med Phys ; 39(6Part6): 3658, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28517569

RESUMEN

PURPOSE: We developed a novel automated estimation method for patient setup errors based on simulated and real portal images for prostate cancer radiotherapy. METHODS: The estimation of patient setup errors in this study was based on a template matching technique with a cross-correlation coefficient and Sobel filter between the real portal image and localized pelvic template of reference image, which were DRR (digitally reconstructed radiography) images and simulated portal images. The simulated portal image was derived by projecting a CT image according to an inverse exponential power law of x-ray attenuation for a water-equivalent path length of each voxel of the CT image on each ray from a source to each pixel on the EPID (electric portal imaging device). A localized pelvic template of each patient in AP (anterior-posterior) or lateral view was automatically extracted from the DRR or simulated portal images by cropping a rectangular region, which was determined by using the mean pelvic template and four anatomical feature points. We applied the proposed method to three prostate cancer cases, and evaluated it using the residual error between the patient setup error obtained by proposed method and the gold standard setup error determined by two radiation oncologists. RESULTS: The average residual errors of the patient setup error for the DRR and simulated portal images were 0.79 and 1.26 mm in the left-right (LR) direction, 3.17 and 2.05 mm in the superior-inferior (SI) direction, 1.69 and 5.82 mm in the anterior-posterior (AP) direction, 3.84 and 6.94 mm in Euclidean distance (ED), respectively. If we used the simulated portal image for LR and SI directions and the DRR image for AP direction, the Euclidean distance was 3.22 mm. CONCLUSIONS: The proposed method has a potential to correctly estimate patient setup errors for prostate cancer radiotherapy.

3.
Med Phys ; 39(6Part5): 3646, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28517624

RESUMEN

PURPOSE: Microsoft Kinect has potential for use in real-time patient position monitoring in diagnostic radiology and radiotherapy. We evaluated the accuracy of depth image data and the device-to-device variation in various conditions simulating clinical applications in a hospital. METHODS: Kinect sensor consists of infrared-ray depth camera and RGB camera. We developed a computer program using OpenNI and OpenCV for measuring quantitative distance data. The program displays depth image obtained from Kinect sensor on the screen, and the cartesian coordinates at an arbitrary point selected by mouse-clicking can be measured. A rectangular box without luster (300 × 198 × 50 mm3 ) was used as a measuring object. The object was placed on the floor at various distances ranging from 0 to 400 cm in increments of 10 cm from the sensor, and depth data were measured for 10 points on the planar surface of the box. The measured distance data were calibrated by using the least square method. The device-to-device variations were evaluated using five Kinect sensors. RESULTS: There was almost linear relationship between true and measured values. Kinect sensor was unable to measure at a distance of less than 50 cm from the sensor. It was found that distance data calibration was necessary for each sensor. The device-to-device variation error for five Kinect sensors was within 0.46% at the distance range from 50 cm to 2 m from the sensor. The maximum deviation of the distance data after calibration was 1.1 mm at a distance from 50 to 150 cm. The overall average error of five Kinect sensors was 0.18 mm at a distance range of 50 to 150 cm. CONCLUSIONS: Kinect sensor has distance accuracy of about 1 mm if each device is properly calibrated. This sensor will be useable for positioning of patients in diagnostic radiology and radiotherapy.

4.
Med Phys ; 39(6Part5): 3646, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28517638

RESUMEN

PURPOSE: Radiographic simulator system is useful for learning radiographic techniques and confirmation of positioning before x-ray irradiation. Conventional x-ray simulators have drawbacks in cost and size, and are only applicable to situations in which position of the object does not change. Therefore, we have developed a new radiographic simulator system using an infrared-ray based three-dimensional shape measurement device (Microsoft Kinect). METHODS: We made a computer program using OpenCV and OpenNI for processing of depth image data obtained from Kinect, and calculated the exact distance from Kinect to the object by calibration. Theobject was measured from various directions, and positional relationship between the x-ray tube and the object was obtained. X-ray projection images were calculated by projecting x-rays onto the mathematical three-dimensional CT data of a head phantom with almost the same size. The object was rotated from 0 degree (standard position) through 90 degrees in increments of 10 degrees, and the accuracy of the measured rotation angle values was evaluated. In order to improve the computational time, the projection image size was changed (512*512, 256*256, and 128*128). RESULTS: The x-ray simulation images corresponding to the radiographic images produced by using the x-ray tube were obtained. The three-dimensional position of the object was measured with good precision from 0 to 50 degrees, but above 50 degrees, measured position error increased with the increase of the rotation angle. The computational time and image size were 30, 12, and 7 seconds for 512*512, 256*256, and 128*128, respectively. CONCLUSIONS: We could measure the three-dimensional position of the object using properly calibrated Kinect sensor, and obtained projection images at relatively high-speed using the three-dimensional CTdata. It was suggested that this system can be used for obtaining simulated projection x-ray images before x-ray exposure by attaching this device onto an x-ray tube.

5.
Med Phys ; 39(6Part24): 3908, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28518700

RESUMEN

PURPOSE: The quality of a treatment plan for stereotactic body radiotherapy (SBRT) depends on an experience of each treatment planner. Therefore, the treatment plans are subjectively determined by comparison of several treatment plans developed by time consuming iterative manners, while considering the benefit to a tumor and the risk to the surrounding normal tissues. The aim of our study was to develop an automated optimization method for beam arrangements based on similar cases in a database including plans designed by senior experienced treatment planners. METHODS: Our proposed method consists of three steps. First, similar cases were automatically selected based on image features from the treatment planning point of view. We defined four types of image features relevant to planning target volume (PTV) location, PTV shape, lung size, and spinal cord positional features. Second, the beam angles of the similar case were registered to the objective case with respect to lung regions using a linear registration technique. Third, the beam direction of the objective case was locally optimized based on the cost function considering radiation absorption in normal tissues and organs at risk. The proposed method was evaluated with 10 test cases and a treatment planning database including 81 cases by using eight planning evaluation indices such as D95, lung V20, and maximum spinal cord dose. RESULTS: The proposed method may provide usable beam directions, which have no statistically significant differences with the original beam directions (P > 0.05) in terms of the seven planning evaluation indices. Moreover, the mean value of D95 for 10 test cases was improved with a statistically significant difference by using the proposed method, compared with the original beam directions (P = 0.03). CONCLUSIONS: The proposed method could be used as a computer-assisted treatment planning tool for determination of beam directions in SBRT.

6.
Med Phys ; 39(6Part28): 3965, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28519622

RESUMEN

PURPOSE: The three-dimensional (3D) dose distribution covering a tumor region tends to be more breakable if the beam's eye view (BEV) of the 3D electron density (ED) map in a beam direction changes more abruptly with large fluctuations. Our aim of this study was to develop an automated determination method of robust beam directions against the patient setup error based on the ED-based BEV in the beam direction in the particle therapy. METHODS: The basic idea of our proposed method was to find the robust beam directions, whose the ED-based BEV has the spatial fluctuations with low special frequency and small amplitude. For evaluation of the spatial fluctuation in the ED-based BEV in a beam direction, we obtained power spectra of the ED-based BEVs in all directions, i.e., 0 to 355 degree, with an interval of 5 degree. It was assumed that as the average spatial frequency and amplitude of the fluctuation in the ED-based BEV in a beam direction is lower and smaller, respectively, the absolute value of a gradient of the power spectrum becomes larger. Therefore the gradient of the power spectrum was calculated for determination of the robust beam direction. The ED-based BEV was produced by projecting a 3D electron density map derived from the computed tomography (CT) image from a beam source to the distal end of a planning target volume (PTV). Four cases of head and neck cancer patients were selected for evaluation of the proposed method. RESULTS: As a preliminary result, radiation oncologists agreed with most beam directions, which seem to be robust against patient setup errors, suggested by the proposed method. CONCLUSIONS: Our proposed method could be feasible to suggest the robust beam directions against patient setup errors in hadron particle therapy.

7.
Med Phys ; 39(6Part7): 3679, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28519782

RESUMEN

PURPOSE: The accumulated dose distributions during the course of radiation treatment are substantially important for verifying whether treatment dose distributions are produced according to planned dose distributions. The purpose of this study was to develop a computer-assisted verification method of accumulated dose distribution during the irradiation of a tumor based on estimation of four-dimensional (4D) dose distribution using an electronic portal imaging device (EPID). METHODS: The 4D 'treatment' computed tomography (CT) images during the irradiation were estimated based on affine transformations including respiratory motions, which were derived by registration between a planning portal dose image and treatment portal dose dynamic image. Planning portal dose images were calculated from planning CT images and an algorithm for calculation of dose spatial distribution. Treatment portal dose images were estimated from EPID dynamic images obtained during a treatment time. The planning portal dose images were registered to the treatment portal dose images to obtain the affine transformation, which could include respiratory motion in a patient body. The CT images at a treatment time were determined by deforming the planning CT images using the affine transformation matrix. 4D dose distributions during a treatment delivery were obtained by applying a dose calculation algorithm to the 4D treatment CT images. Finally, accumulated dose distributions during the course of radiation treatment were verified with planned dose distributions. RESULTS: We applied the proposed method to EPID dynamic images of 2 lung cancer patients, and evaluated the difference in accumulated dose distribution between the plan and treatment using a gamma evaluation (3mm/3%). The average pass rate for 2 cases was 78.2%. CONCLUSIONS: The proposed method can be used for adaptively modifying the plan based on the dose discrepancy between the plan and treatment. This work was partially supported by Grant-in-Aid for Scientific Research (C) (22611011) and Okawa Foundation for Information and Telecommunications.

8.
Phys Med Biol ; 54(3): 665-77, 2009 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-19131668

RESUMEN

The purpose of this study was to develop a computerized method for estimation of the location of a lung tumor in cine images on an electronic portal imaging device (EPID) without implanted markers during stereotactic body radiotherapy (SBRT). Each tumor region was segmented in the first EPID cine image, i.e., reference portal image, based on a multiple-gray level thresholding technique and a region growing technique, and then the image including the tumor region was cropped as a 'tumor template' image. The tumor location was determined as the position in which the tumor template image took the maximum cross-correlation value within each consecutive portal image, which was acquired in cine mode on the EPID in treatment. EPID images with 512 x 384 pixels (pixel size: 0.56 mm) were acquired at a sampling rate of 0.5 frame s(-1) by using energies of 4, 6 or 10 MV on linear accelerators. We applied our proposed method to EPID cine images (226 frames) of 12 clinical cases (ages: 51-83, mean: 72) with a non-small cell lung cancer. As a result, the average location error between tumor points obtained by our method and the manual method was 1.47 +/- 0.60 mm. This preliminary study suggests that our method based on the tumor template matching technique might be feasible for tracking the location of a lung tumor without implanted markers in SBRT.


Asunto(s)
Algoritmos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Radiocirugia/métodos , Técnica de Sustracción , Cirugía Asistida por Computador/métodos , Pantallas Intensificadoras de Rayos X , Inteligencia Artificial , Humanos , Reconocimiento de Normas Patrones Automatizadas/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
AJNR Am J Neuroradiol ; 29(6): 1153-8, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18388216

RESUMEN

BACKGROUND AND PURPOSE: Previous studies have suggested that use of an artificial neural network (ANN) system is beneficial for radiological diagnosis. Our purposes in this study were to construct an ANN for the differential diagnosis of intra-axial cerebral tumors on MR images and to evaluate the effect of ANN outputs on radiologists' diagnostic performance. MATERIALS AND METHODS: We collected MR images of 126 patients with intra-axial cerebral tumors (58 high-grade gliomas, 37 low-grade gliomas, 19 metastatic tumors, and 12 malignant lymphomas). We constructed a single 3-layer feed-forward ANN with a Levenberg-Marquardt algorithm. The ANN was designed to differentiate among 4 categories of tumors (high-grade gliomas, low-grade gliomas, metastases, and malignant lymphomas) with use of 2 clinical parameters and 13 radiologic findings in MR images. Subjective ratings for the 13 radiologic findings were provided independently by 2 attending radiologists. All 126 cases were used for training and testing of the ANN based on a leave-one-out-by-case method. In the observer test, MR images were viewed by 9 radiologists, first without and then with ANN outputs. Each radiologist's performance was evaluated through a receiver operating characteristic (ROC) analysis on a continuous rating scale. RESULTS: The averaged area under the ROC curve for ANN alone was 0.949. The diagnostic performance of the 9 radiologists increased from 0.899 to 0.946 (P < .001) when they used ANN outputs. CONCLUSIONS: The ANN can provide useful output as a second opinion to improve radiologists' diagnostic performance in the differential diagnosis of intra-axial cerebral tumors seen on MR imaging.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Redes Neurales de la Computación , Reconocimiento de Normas Patrones Automatizadas/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Neurology ; 63(3): 577-80, 2004 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-15304601

RESUMEN

The authors report a Japanese family segregating autosomal recessive Charcot-Marie-Tooth disease (CMT) with focally folded myelin, juvenile-onset glaucoma, and a nonsense mutation of SET binding factor 2 (SBF2). The consistent phenotypic features associated with SBF2 mutations are early-onset demyelinating neuropathy, myelin folding, and markedly decreased motor nerve conduction velocities; glaucoma associates with SBF2 nonsense mutations.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/genética , Codón sin Sentido , Glaucoma de Ángulo Abierto/genética , Proteínas Tirosina Fosfatasas/genética , Adolescente , Adulto , Edad de Inicio , Enfermedad de Charcot-Marie-Tooth/clasificación , Enfermedad de Charcot-Marie-Tooth/complicaciones , Enfermedad de Charcot-Marie-Tooth/enzimología , Enfermedad de Charcot-Marie-Tooth/epidemiología , Niño , Consanguinidad , Análisis Mutacional de ADN , Femenino , Genes Recesivos , Heterogeneidad Genética , Genotipo , Glaucoma de Ángulo Abierto/epidemiología , Glaucoma de Ángulo Abierto/etiología , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Linaje , Fenotipo , Proteínas Tirosina Fosfatasas/deficiencia , Proteínas Tirosina Fosfatasas/fisiología , Proteínas Tirosina Fosfatasas no Receptoras , Procesamiento Postranscripcional del ARN , ARN Mensajero/metabolismo
11.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 59(3): 396-7, 2003 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-12740561

RESUMEN

PURPOSE: In picture archiving and communication systems (PACS), the information on the body parts included in radiographs is often not or incorrectly recorded in an image header. In order to apply the computer-aided diagnosis (CAD) system in the PACS environment, the body parts in radiographs need to be recognized correctly by computer. The purpose of this study is to develop a computerized method for correctly classifying the body parts in digital radiographs based on a template matching technique. METHODS/MATERIALS: The image database used in this study was 1032 digital radiographs (14 x 17 inches) obtained with a computed radiography, and included 505 chest of postetroanterior view, 39 chest of lateral view, 241 abdomen, 108 pelvis, 10 upper limbs, 125 lower limbs, and 4 thoracic spine. In this method, test images were classified into four body parts, i.e., (1) chest, (2) abdomen, (3) pelvis, and (4) upper/lower limbs and thoracic spine. This computerized method was tested with 852 images, since 180 images were employed for creation of 98 templates, which represented the average radiographs for various body parts. Our approach was to examine the similarity of a given test image with templates by use of the cross-correlation values as the similarity measures. The body part of the test image was identified as the body part in the template yielding the maximum correlation value. Our method consisted of the following five steps. First, test images were classified into one of three groups; i.e. 1) chest and abdomen, 2) pelvis, and 3) upper/lower limbs and thoracic spine by using the templates obtained from images with the average size and position. Second, the remaining uncertain images were classified by using additional templates in various directions. Third, the chest and abdomen group was separated into two subgroups; i.e.chest and abdomen. Fourth, in order to classify some uncertain images, templates were shifted horizontally and vertically. Fifth, outer pixels of templates were eliminated to avoid the misclassification due to x-ray collimation. RESULTS: Our preliminary results indicated that the body parts for 850 cases (99.8%) were correctly classified with our method. CONCLUSIONS: This method would be useful for automated identification of the body parts in radiographs when various CAD systems would be implemented in the PACS environment.


Asunto(s)
Diagnóstico por Computador/métodos , Procesamiento Automatizado de Datos/métodos , Cuerpo Humano , Intensificación de Imagen Radiográfica/métodos , Sistemas de Información Radiológica , Humanos
12.
Protein Expr Purif ; 21(1): 87-91, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11162391

RESUMEN

Direct expression of the cytokine receptor homology (CRH) domain of granulocyte-colony-stimulating factor (G-CSF) receptor is lethal to Escherichia coli. For the efficient and stable production of an active CRH domain in E. coli, we fused the CRH domain with different proteins, such as maltose-binding protein (MalE), glutathione S-transferase, and thioredoxin (Trx). Among these, Trx appeared to be the best in terms of the protein expression level, purification efficiency by affinity chromatography, and binding activity to its ligand, G-CSF. The yield of active Trx-CRH fusion protein increased about 200-fold compared to that of previously reported MalE-CRH fusion.


Asunto(s)
Transportadoras de Casetes de Unión a ATP , Proteínas de Escherichia coli , Proteínas de Transporte de Monosacáridos , Proteínas de Unión Periplasmáticas , Receptores de Citocinas/química , Receptores de Factor Estimulante de Colonias de Granulocito/química , Receptores de Factor Estimulante de Colonias de Granulocito/metabolismo , Sustitución de Aminoácidos , Proteínas Portadoras/metabolismo , Cromatografía de Afinidad , Clonación Molecular/métodos , Cisteína , Electroforesis en Gel de Poliacrilamida , Escherichia coli , Glutatión Transferasa/metabolismo , Factor Estimulante de Colonias de Granulocitos , Humanos , Cinética , Proteínas de Unión a Maltosa , Mutagénesis Sitio-Dirigida , Plásmidos , Receptores de Factor Estimulante de Colonias de Granulocito/genética , Receptores de Factor Estimulante de Colonias de Granulocito/aislamiento & purificación , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Mapeo Restrictivo , Tiorredoxinas/metabolismo , Dominios Homologos src
13.
Neurology ; 55(3): 392-7, 2000 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-10932274

RESUMEN

OBJECTIVE: We describe three patients from a family with motor and sensory neuropathy accompanied by open-angle glaucoma. BACKGROUND: Autosomal recessive demyelinating hereditary motor and sensory neuropathies (HMSN) include different disorders. To our knowledge, autosomal recessive HMSN has not been associated with juvenile onset glaucoma. METHODS: Sural nerve pathology of the three patients were examined, and genetic analysis of the family was performed. RESULT: - The most prominent pathologic finding was a highly unusual myelin abnormality consisting of irregular redundant loops and folding of the myelin sheath. The family survey supports autosomal recessive inheritance. The molecular analysis failed to demonstrate either linkage of the disease to MPZ gene, PMP22 gene, Cx32 gene, orEGR2 gene. Analysis did not establish linkage of the disease to the locus of CMT4A, 4B, and 4C genes. CONCLUSION: The present cases may represent a new type of HMSN accompanied by juvenile onset glaucoma.


Asunto(s)
Glaucoma de Ángulo Abierto/complicaciones , Neuropatía Hereditaria Motora y Sensorial/complicaciones , Vaina de Mielina/química , Adulto , Análisis Mutacional de ADN , Femenino , Genes Recesivos , Ligamiento Genético , Glaucoma de Ángulo Abierto/genética , Glaucoma de Ángulo Abierto/patología , Neuropatía Hereditaria Motora y Sensorial/genética , Neuropatía Hereditaria Motora y Sensorial/patología , Humanos , Japón , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Vaina de Mielina/genética , Vaina de Mielina/patología , Vaina de Mielina/ultraestructura , Linaje , Pliegue de Proteína , Nervio Sural/patología , Nervio Sural/ultraestructura
15.
Phys Med Biol ; 44(5): 1337-52, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10368023

RESUMEN

Rossmann proposed that the Wiener spectra of the quantum mottle of radiographs made using screen-film systems were proportional to the squares of the modulation transfer functions (MTFs) of the screen-film systems. On the other hand, Lubberts theoretically pointed out that the shape of the Wiener spectrum of the quantum mottle depended on the sum of the squares of the MTFs for different depths in the screen phosphor layer, rather than the square of the sum of the MTFs for the different depths, i.e. the square of the MTF of the screen-film systems. The purpose of this study is to experimentally investigate the proportionality between the Wiener spectra of the quantum mottle and the squares of the MTFs of screen-film systems using two screen-film systems having different screen thicknesses. For this purpose, we determined correction factors for the square of the MTF of the screen-film system in the Wiener spectrum of the quantum mottle at each spatial frequency when the Wiener spectral values of the screen mottle were separated into those of the quantum mottle and structure mottle. The correction factor is the ratio of the normalized Wiener spectrum of the quantum mottle to the square of the MTF of the screen-film system. As a result, for a thin screen, the correction factors were unity for all spatial frequencies; on the contrary, for a thick screen, the factor increased with spatial frequency. By calculating the theoretical correction factors using the models for the MTF and Wiener spectrum of the quantum mottle of Nishikawa and Yaffe based on Lubberts' theory, we verified that our experimental results agreed with Lubberts' theory. Furthermore, by obtaining the screen thickness dependence of the theoretical correction factors for the two screens, we showed that, for screens thinner than 0.02 mm, Rossmann's theory can be applied to the relationship between the Wiener spectrum of the quantum mottle and the MTF of the screen-film system, whereas for screens thicker than 0.02 mm, Lubberts' theory should be applied.


Asunto(s)
Pantallas Intensificadoras de Rayos X , Fenómenos Biofísicos , Biofisica , Humanos , Modelos Teóricos , Óptica y Fotónica , Fotones , Pantallas Intensificadoras de Rayos X/estadística & datos numéricos
16.
Rinsho Shinkeigaku ; 39(11): 1135-7, 1999 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-10689936

RESUMEN

We reported a 52-year-old man and his family with bulbospinal muscle atrophy (BSMA) and gynecomastia. The propositus presented with the clinical picture of late onset progressive bulbospinal muscular atrophy including postural tremor, general hyporeflexia, mild maturity onset diabetes, gynecomastia and sexual impotence. One of his brother and his two sons had gynecomastia. His elder son had ocular movement abnormality, associated movement of facial muscle and finger tremor. One of his brothers showed tongue fasciculation without gynecomastia. None of members examined had abnormal expansion of CAG repeats in the androgen receptor gene. We speculate that this family has a new clinical entity characterized by bulbospinal muscular atrophy with an autosomal dominant inheritance.


Asunto(s)
Genes Dominantes , Ginecomastia/genética , Trastornos Musculares Atróficos/genética , Anciano , Anciano de 80 o más Años , Femenino , Ginecomastia/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Trastornos Musculares Atróficos/complicaciones , Trastornos Musculares Atróficos/fisiopatología , Receptores Androgénicos/genética , Expansión de Repetición de Trinucleótido
17.
Muscle Nerve ; 21(11): 1390-7, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9771661

RESUMEN

Crow-Fukase or POEMS syndrome of polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes is a rare multisystem disorder of obscure pathogenesis that is associated with microangiopathy, neovascularization, and accelerated vasopermeability. We examined the levels of the vascular endothelial growth factor/vascular permeability factor (VEGF) in the serum and cerebrospinal fluid (CSF) from 10 patients with this syndrome. Serum VEGF levels were about 15-30 times those in control subjects or patients with Guillain-Barré syndrome (GBS), chronic inflammatory demyelinating polyneuropathy (CIDP), and other neurological disorders. The CSF VEGF levels, however, were similar to those found in GBS and CIDP. Elevated VEGF levels in the serum decreased in 7 patients with Crow-Fukase syndrome after conventional therapy. The principal isoform of VEGF in Crow-Fukase syndrome was VEGF165. Elevated VEGF was independent of M-protein. Our results suggest that the overproduction of VEGF is important in the pathogenesis of this disorder.


Asunto(s)
Factores de Crecimiento Endotelial/sangre , Linfocinas/sangre , Proteínas de Mieloma , Síndrome POEMS/etiología , Síndrome POEMS/metabolismo , Adulto , Anciano , Western Blotting , Conectina , Factores de Crecimiento Endotelial/análisis , Factores de Crecimiento Endotelial/química , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulinas/análisis , Inmunoterapia , Isomerismo , Linfocinas/análisis , Linfocinas/química , Masculino , Persona de Mediana Edad , Peso Molecular , Proteínas Musculares/análisis , Proteínas Musculares/sangre , Síndrome POEMS/terapia , Polineuropatías/etiología , Polineuropatías/metabolismo , Polineuropatías/terapia , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
18.
Med Phys ; 25(9): 1625-35, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9775367

RESUMEN

The radiographic density fluctuations produced by using dual screen-film systems are designated as the radiographic mottle. The density fluctuation of the radiographic mottle for the double emulsions at a density of the double emulsions consists of those for the front and back emulsions on a radiograph. However, the relation between the Wiener spectra of the radiographic mottle for the double and single emulsions had not been studied. Hence we compared the Wiener spectra of the radiographic mottle for the double emulsions with the sum of those for the front and back emulsions on the same radiographs and with the sum of those for the emulsions at the same densities. At all densities of more than 0.62 for lower spatial frequencies (< or = 1 mm-1), the Wiener spectral values of the radiographic mottle for the double emulsions were greater than the sum of those for the front and back emulsions for both comparisons on the same radiographs and at the same densities. In order to investigate the reason of the above phenomena, we separated the Wiener spectral values of the radiographic mottle for various densities into those of the three factors, i.e., quantum mottle, structure mottle, and film granularity, and performed the same comparisons as the radiographic mottle. Also, to explain the results for the three factors, we obtained the Wiener spectral values of the spatial fluctuations of the light exposure or the fluorescence intensity and the gradients of the characteristic curves of the film for the double and single emulsions of the x-ray film. As a result of the investigation, we found that the phenomena on the radiographic mottle were caused by that (1) on the same radiographs the squares of the gradients of the characteristic curves for the double emulsions were about 5.3 times as great as those for the single emulsion at densities of more than 0.62 of the double emulsions, and (2) at the same density of more than 0.62 those were more than about 2.2 times as great as those for the single emulsion.


Asunto(s)
Película para Rayos X , Fenómenos Biofísicos , Biofisica , Emulsiones , Estudios de Evaluación como Asunto , Humanos , Modelos Teóricos , Análisis Espectral , Tecnología Radiológica
20.
Intern Med ; 36(3): 191-3, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9144011

RESUMEN

A 47-year-old man died from fatal pulmonary hemorrhage. Cardiac angiosarcoma with lung metastases was found at postmortem examination. His chest radiograph showed bilateral, diffuse nodular infiltrates without cardiomegaly. No cardiac signs and symptoms were observed. The clinical outcome was rapidly fatal. Angiosarcoma of the heart should be suspected in patients with hemoptysis and nodular chest radiograph abnormalities, even in the absence of cardiac signs and symptoms.


Asunto(s)
Neoplasias Cardíacas/complicaciones , Hemangiosarcoma/complicaciones , Hemorragia/etiología , Enfermedades Pulmonares/etiología , Resultado Fatal , Atrios Cardíacos , Neoplasias Cardíacas/patología , Hemangiosarcoma/secundario , Hemoptisis/etiología , Humanos , Neoplasias Pulmonares/secundario , Masculino , Persona de Mediana Edad
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