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1.
Biomed Eng Lett ; 12(1): 75-84, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35186361

RESUMEN

Cardiac cine-MRI is one of the most important diagnostic tools used to assess the morphology and physiology of the heart during the cardiac cycle. Nonetheless, the analysis on cardiac cine-MRI is poorly exploited and remains highly dependent on the observer's expertise. This work introduces an imaging cardiac disease representation, coded as an embedding vector, that fully exploits hidden mapping between the latent space and a generated cine-MRI data distribution. The resultant representation is progressively learned and conditioned by a set of cardiac conditions. A generative cardiac descriptor is achieved from a progressive generative-adversarial network trained to produce MRI synthetic images, conditioned to several heart conditions. The generator model is then used to recover a digital biomarker, coded as an embedding vector, following a backpropagation scheme. Then, an UMAP strategy is applied to build a topological low dimensional embedding space that discriminates among cardiac pathologies. Evaluation of the approach is carried out by using an embedded representation as a potential disease descriptor in 2296 pathological cine-MRI slices. The proposed strategy yields an average accuracy of 0.8 to discriminate among heart conditions. Furthermore, the low dimensional space shows a remarkable grouping of cardiac classes that may suggest its potential use as a tool to support diagnosis. The learned progressive and generative representation, from cine-MRI slices, allows retrieves and coded complex descriptors that results useful to discriminate among heart conditions. The cardiac disease representation expressed as a hidden embedding vector could potentially be used to support cardiac analysis on cine-MRI sequences.

2.
Arch Gynecol Obstet ; 300(3): 545-553, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31256232

RESUMEN

PURPOSE: To review the literature on uterine contraction and to highlight magnetic resonance imaging using the cine technique as a useful method to evaluate these movements. METHODS: The literature research on PubMed database was done up to February 2019 with restriction to English language about articles regarding uterine peristalsis and cine MR. RESULTS: Infertility is a common clinical problem and a source of frustration for those who want to have children. Uterine movements are crucial elements in respect of successful conception, implantation, and the development of a healthy pregnancy. It is known that the direction and frequency of uterine peristalsis are closely related to the different phases of the menstrual cycle, and that changes in its activity may interfere with reproduction. One condition that has been linked with infertility by several studies is dysfunctional uterine contractility. Magnetic resonance imaging, using the cine technique, has been shown to be a useful tool in the evaluation of these movements, allowing the identification of patients with some type of dysfunction and establish strategies to increase pregnancy rates. CONCLUSION: Cine MR is an excellent imaging method for the evaluation of uterine peristalsis and identification of dysfunctional contractions.


Asunto(s)
Imagen por Resonancia Cinemagnética/métodos , Ciclo Menstrual/fisiología , Contracción Uterina/fisiología , Útero/diagnóstico por imagen , Adulto , Niño , Femenino , Humanos , Útero/fisiología
3.
J. appl. oral sci ; J. appl. oral sci;24(5): 472-480, Sept.-Oct. 2016. tab, graf
Artículo en Inglés | LILACS, BBO - Odontología | ID: lil-797978

RESUMEN

ABSTRACT Objective Since the tongue is the oral structure responsible for mastication, pronunciation, and swallowing functions, patients who undergo glossectomy can be affected in various aspects of these functions. The vowel /i/ uses the tongue shape, whereas /u/ uses tongue and lip shapes. The purpose of this study is to investigate the morphological changes of the tongue and the adaptation of pronunciation using cine MRI for speech of patients who undergo glossectomy. Material and Methods Twenty-three controls (11 males and 12 females) and 13 patients (eight males and five females) volunteered to participate in the experiment. The patients underwent glossectomy surgery for T1 or T2 lateral lingual tumors. The speech tasks “a souk” and “a geese” were spoken by all subjects providing data for the vowels /u/ and /i/. Cine MRI and speech acoustics were recorded and measured to compare the changes in the tongue with vowel acoustics after surgery. 2D measurements were made of the interlip distance, tongue-palate distance, tongue position (anterior-posterior and superior-inferior), tongue height on the left and right sides, and pharynx size. Vowel formants Fl, F2, and F3 were measured. Results The patients had significantly lower F2/Fl ratios (F=5.911, p=0.018), and lower F3/F1 ratios that approached significance. This was seen primarily in the /u/ data. Patients had flatter tongue shapes than controls with a greater effect seen in /u/ than /i/. Conclusion The patients showed complex adaptation motion in order to preserve the acoustic integrity of the vowels, and the tongue modified cavity size relationships to maintain the value of the formant frequencies.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Faringe/patología , Habla/fisiología , Lengua/fisiopatología , Lengua/patología , Glosectomía/rehabilitación , Faringe/fisiopatología , Periodo Posoperatorio , Valores de Referencia , Acústica del Lenguaje , Neoplasias de la Lengua/cirugía , Neoplasias de la Lengua/fisiopatología , Neoplasias de la Lengua/patología , Estudios de Casos y Controles , Estudios Retrospectivos , Análisis de Varianza , Resultado del Tratamiento , Imagen por Resonancia Cinemagnética , Puntos Anatómicos de Referencia , Estadificación de Neoplasias
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