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1.
Pediatr Radiol ; 54(5): 715-724, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38285191

RESUMEN

BACKGROUND: The mediastinal shift angle is a new fetal magnetic resonance imaging (MRI) index that is reportedly correlated with postnatal survival in fetuses with congenital diaphragmatic hernia. However, its correlation in patients with congenital pulmonary airway malformation (CPAM) has not been assessed. OBJECTIVE: This study aimed to establish a normal range for the right/left mediastinal shift angles, to evaluate the mediastinal shift angle in fetuses with CPAM, to compare the mediastinal shift angle with the CPAM volume ratio, and to evaluate the predictive value of the mediastinal shift angle measurements. MATERIALS AND METHODS: To establish the normal range, we measured the mediastinal shift angle bilaterally in 124 fetuses without any lung abnormality (the control group). Subsequently, the mediastinal shift angle was measured in 32 fetuses pathologically diagnosed with CPAM. Moreover, the mediastinal shift angle and CPAM volume ratio were compared using fetal MRI. RESULTS: The mean values for the right/left mediastinal shift angles were 18.6°/26.3° and 39.2°/35.9° for control fetuses and fetuses with CPAM, respectively. The mediastinal shift angle and the CPAM volume ratio showed a positive statistical correlation. The area under the curve demonstrated high discriminatory accuracy for the mediastinal shift angle (0.76). CONCLUSION: The mediastinal shift angle has potential to replace the CPAM volume ratio for evaluating the severity of CPAM in fetal MRI.


Asunto(s)
Imagen por Resonancia Magnética , Diagnóstico Prenatal , Humanos , Femenino , Imagen por Resonancia Magnética/métodos , Diagnóstico Prenatal/métodos , Embarazo , Mediastino/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Pulmón/anomalías , Pulmón/embriología , Malformación Adenomatoide Quística Congénita del Pulmón/diagnóstico por imagen , Valores de Referencia , Estudios Retrospectivos
2.
J Magn Reson Imaging ; 59(1): 32-42, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37288953

RESUMEN

Zero echo time (ZTE) sequence is recent advanced magnetic resonance technique that utilizes ultrafast readouts to capture signals from short-T2 tissues. This sequence enables T2- and T2* weighted imaging of tissues with short intrinsic relaxation times by using an extremely short TE, and are increasingly used in the musculoskeletal system. We review the imaging physics of these sequences, practical limitations, and image reconstruction, and then discuss the clinical utilities in various disorders of the musculoskeletal system. ZTE can be readily incorporated into the clinical workflow, and is a promising technique to avoid unnecessary radiation exposure, cost, and time-consuming by computed tomography in some cases. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 1.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Sistema Musculoesquelético , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Sistema Musculoesquelético/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Imagen por Resonancia Magnética/métodos
4.
Jpn J Radiol ; 40(11): 1156-1165, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35727458

RESUMEN

PURPOSE: To develop a support vector machine (SVM) classifier using CT texture-based analysis in differentiating focal-type autoimmune pancreatitis (AIP) and pancreatic duct carcinoma (PD), and to assess the radiologists' diagnostic performance with or without SVM. MATERIALS AND METHODS: This retrospective study included 50 patients (20 patients with focal-type AIP and 30 patients with PD) who underwent dynamic contrast-enhanced CT. Sixty-two CT texture-based features were extracted from 2D images of the arterial and portal phase CTs. We conducted data compression and feature selections using principal component analysis (PCA) and produced the SVM classifier. Four readers participated in this observer performance study and the statistical significance of differences with and without the SVM was assessed by receiver operating characteristic (ROC) analysis. RESULTS: The SVM performance indicated a high performance in differentiating focal-type AIP and PD (AUC = 0.920). The AUC for all 4 readers increased significantly from 0.827 to 0.911 when using the SVM outputs (p = 0.010). The AUC for inexperienced readers increased significantly from 0.781 to 0.905 when using the SVM outputs (p = 0.310). The AUC for experienced readers increased from 0.875 to 0.912 when using the SVM outputs, however, there was no significant difference (p = 0.018). CONCLUSION: The use of SVM classifier using CT texture-based features improved the diagnostic performance for differentiating focal-type AIP and PD on CT.


Asunto(s)
Pancreatitis Autoinmune , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Pancreatitis Autoinmune/diagnóstico por imagen , Estudios Retrospectivos , Diagnóstico Diferencial , Carcinoma Ductal Pancreático/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Aprendizaje Automático , Conductos Pancreáticos , Radiólogos , Neoplasias Pancreáticas
5.
J UOEH ; 43(2): 235-242, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34092768

RESUMEN

Endometrioid carcinoma is the most common histological type of concurrent synchronous cancers of the uterus and ovary. Here we report a case of synchronous seromucinous carcinoma of the ovary and mucinous carcinoma of the endometrium with a literature review. A 51-year-old multiparous female complained of irregular bleeding and shortness of breath. Computed tomography revealed a large pelvic mass that consisted of cystic and solid components, a tumor of the endometrium, and a large amount of pleural effusion. An endometrial biopsy indicated adenocarcinoma, and adenocarcinoma cells were found in the pleural fluid. The patient with advanced ovarian cancer or endometrial cancer with massive pleural effusion received three courses of neoadjuvant chemotherapy (NAC) with paclitaxel and carboplatin followed by interval debulking surgery (IDS). The NAC was effective, and IDS was performed with no gross residual lesions. The post-operative diagnosis was seromucinous carcinoma of the ovary in FIGO (2014) stage IVA (ypT3cNxM1a) and mucinous carcinoma of the endometrium in FIGO (2008) stage IA (ypT1aNXM0). Three courses of postoperative TC therapy were performed, and maintenance therapy with Bevacizumab is ongoing. The patient is well without evidence of recurrence, sixteen months after surgery.


Asunto(s)
Adenocarcinoma Mucinoso , Carcinoma Endometrioide , Neoplasias Endometriales , Neoplasias Ováricas , Adenocarcinoma Mucinoso/diagnóstico por imagen , Adenocarcinoma Mucinoso/tratamiento farmacológico , Adenocarcinoma Mucinoso/cirugía , Carcinoma Endometrioide/cirugía , Neoplasias Endometriales/terapia , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Neoplasias Ováricas/diagnóstico por imagen
6.
Asian Cardiovasc Thorac Ann ; 25(4): 307-309, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28457170

RESUMEN

The patient was a 56-year-old woman with Kommerell's diverticulum associated with a right-sided aortic arch with mirror-image branching. No other congenital heart anomalies or vascular rings were observed. Descending aortic replacement through a right posterolateral thoracotomy was performed to eliminate the risk of diverticular rupture. The patient's postoperative course was uneventful. This was a rare adult case of right-sided aortic arch with Kommerell's diverticulum associated with no other congenital heart disease.


Asunto(s)
Aorta Torácica/anomalías , Enfermedades de la Aorta/complicaciones , Divertículo/complicaciones , Aorta Torácica/diagnóstico por imagen , Aorta Torácica/cirugía , Enfermedades de la Aorta/diagnóstico por imagen , Enfermedades de la Aorta/cirugía , Aortografía/métodos , Angiografía por Tomografía Computarizada , Divertículo/diagnóstico por imagen , Divertículo/cirugía , Femenino , Implantación de Prótesis de Válvulas Cardíacas , Humanos , Persona de Mediana Edad , Toracotomía , Resultado del Tratamiento
7.
Tissue Eng Part A ; 23(23-24): 1394-1402, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28530133

RESUMEN

The aim of this study was to assess the efficacy of a self-assembling peptide hydrogel as a scaffold for bone regeneration. We used a neutral and injectable self-assembling peptide hydrogel, SPG-178-Gel. Bone defects (5 mm in diameter) in rat calvarial bones were filled with a mixture of alpha-modified Eagle's medium and peptide hydrogel. Three weeks after surgery, soft X-ray and microcomputed tomography (micro-CT) images of the gel-treated bones showed new bone formations in the periphery and in central areas of the defects. Next, we evaluated the three-dimensional osteogenic induction of dental pulp stem cells (DPSCs), a type of mesenchymal stem cell, in SPG-178-Gel. We first confirmed that the osteogenic differentiation of DPSCs was significantly promoted by osteogenic induction medium containing recombinant human bone morphogenetic protein-4 (rhBMP-4) in a two-dimensional cell culture. Then, we verified DPSC proliferation and osteogenic differentiation in a three-dimensional cell culture using SPG-178-Gel. The gene expression levels of osteopontin, osteocalcin, and collagen type I were significantly increased when DPSCs were cultured in SPG-178-Gel with the osteogenic induction medium. Micro-CT observations showed the formation of widespread calcium deposition. In conclusion, SPG-178-Gel was adequately effective as a scaffold and can be a suitable tool for bone formation in vivo and in vitro. These findings suggest that the self-assembling peptide hydrogel, SPG-178-Gel, could be a promising tool for bone tissue engineering.


Asunto(s)
Regeneración Ósea/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Pulpa Dental/metabolismo , Hidrogeles , Células Madre Mesenquimatosas/metabolismo , Osteogénesis/efectos de los fármacos , Péptidos , Animales , Antígenos de Diferenciación/biosíntesis , Pulpa Dental/citología , Hidrogeles/química , Hidrogeles/farmacología , Masculino , Células Madre Mesenquimatosas/citología , Péptidos/química , Péptidos/farmacología , Ratas , Ratas Sprague-Dawley
8.
IEEE Trans Vis Comput Graph ; 21(11): 1221-9, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26439824

RESUMEN

This paper proposes a novel radiometric compensation technique for cooperative projection system based-on distributed optimization. To achieve high scalability and robustness, we assume cooperative projection environments such that 1. each projector does not have information about other projectors as well as target images, 2. the camera does not have information about the projectors either, while having the target images, and 3. only a broadcast communication from the camera to the projectors is allowed to suppress the data transfer bandwidth. To this end, we first investigate a distributed optimization based feedback mechanism that is suitable for the required decentralized information processing environment. Next, we show that this mechanism works well for still image projection, however not necessary for moving images due to the lack of dynamic responsiveness. To overcome this issue, we propose to implement an additional feedforward mechanism. Such a 2 Degree Of Freedom (2-DOF) control structure is well-known in control engineering community as a typical method to enhance not only disturbance rejection but also reference tracking capability, simultaneously. We theoretically guarantee and experimentally demonstrate that this 2-DOF structure yields the moving image projection accuracy that is overwhelming the best achievable performance only by the distributed optimization mechanisms.

9.
Opt Express ; 20(21): 23659-65, 2012 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-23188331

RESUMEN

We report a substantial increase in the heat resistance in a connector-type single-wall carbon nanotube (SWNT) saturable absorber by sealing SWNT/P3HT composite with siloxane. By applying the saturable absorber to a passively mode-locked Er fiber laser, we successfully demonstrated 280 fs, 31 mW pulse generation with a fivefold improvement in heat resistance.


Asunto(s)
Tecnología de Fibra Óptica/instrumentación , Rayos Láser , Nanotecnología/instrumentación , Nanotubos de Carbono/química , Compuestos de Organoselenio/química , Siloxanos/química , Absorción , Diseño de Equipo , Análisis de Falla de Equipo , Nanotubos de Carbono/ultraestructura , Conductividad Térmica
10.
Opt Express ; 18(9): 9712-21, 2010 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-20588820

RESUMEN

We successfully fabricated a cascadable film-type single-wall carbon nanotube (SWNT) saturable absorber coated on aromatic polyamide film, in which the saturable absorption effect can be controlled with the number of films. A conductive polymer P3HT (poly-3-hexylthiophene) was adopted to obtain a uniform SWNT solution. We applied saturable absorber films to a passively mode-locked fiber laser and successfully generated a 113 fs, 42 MHz pulse by inserting two film layers between fiber connectors in the cavity.

11.
Opt Express ; 18(11): 11223-9, 2010 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-20588982

RESUMEN

We present a 1.07 microm all-fiber femtosecond soliton laser employing a film-type saturable absorber with a P3HT (poly-3-hexylthiophene) incorporated SWNT coated on polyimide film. We optimized the laser cavity as a dispersion-managed soliton laser with photonic crystal fiber (PCF) as an anomalous dispersion fiber at 1.07 microm. As a result, a 131 fs, 33 MHz pulse was successfully generated with a simple laser configuration.


Asunto(s)
Tecnología de Fibra Óptica/instrumentación , Rayos Láser , Membranas Artificiales , Nanotubos/química , Compuestos de Organoselenio/química , Diseño de Equipo , Análisis de Falla de Equipo , Miniaturización , Nanotubos/ultraestructura , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
Opt Express ; 16(25): 20943-8, 2008 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-19065233

RESUMEN

We fabricated a fiber-connector-type saturable absorber in which SWNTs and P3HT (poly-3-hexylthiophene) were coated on the fiber connector end. This saturable absorber allowed us to realize a short laser cavity length. We used a soliton cavity configuration to generate the shortest pulse (147 fs) at the highest repetition rate (51 MHz) yet obtained with carbon nanotubes (CNT) related saturable absorbers.


Asunto(s)
Rayos Láser , Modelos Teóricos , Nanotecnología/instrumentación , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestructura , Fibras Ópticas , Compuestos de Organoselenio/química , Simulación por Computador , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Dispersión de Radiación
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