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1.
Otol Neurotol ; 31(3): 486-91, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20042993

RESUMEN

OBJECTIVE: To produce a reliable objective method of assessing the House-Brackmann (H-B) and regional grades of facial palsy with the results produced and presented in a time and manner suitable for a routine clinical setting. STUDY DESIGN: Analysis of video pixel data using artificial neural networks (ANNs). SETTING: Tertiary-referral neuro-otologic center. SUBJECTS: Subjects with varying degrees of unilateral facial palsy. METHOD: Clinicians assessed videos of subjects with varying degrees of facial palsy performing prescribed movements. The results of their overall and regional assessments were used to train ANNs. These were then tested for consistency, accuracy, and ability to identify clinical changes in grading. RESULTS: A group of subjects had their objective computer assessment repeated, and consistent H-B and regional grades were obtained. A second group had both subjective clinical and objective computer assessments performed. The program gave results that were within the expected level of agreement with the subjective clinical assessment for both H-B and regional grades. A third group had repeated clinical and computer assessments from the time of onset to recovery of facial function. The changes in the computer results both for H-B and regional grades tracked the clinical change. CONCLUSION: It is possible to measure consistently and objectively the H-B and regional grades of facial palsy using trained ANNs to analysis video pixel data, and this can be done in a routine clinical environment by a technician. The results from each region of the face are presented as a Facogram along with the H-B grade.


Asunto(s)
Parálisis Facial/diagnóstico , Parálisis Facial/fisiopatología , Interpretación de Imagen Asistida por Computador/métodos , Índice de Severidad de la Enfermedad , Electrodiagnóstico , Humanos , Movimiento , Grabación en Video
2.
IEEE Trans Biomed Eng ; 56(7): 1864-70, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19336281

RESUMEN

Facial paralysis is the loss of voluntary muscle movement of one side of the face. A quantitative, objective, and reliable assessment system would be an invaluable tool for clinicians treating patients with this condition. This paper presents a novel framework for objective measurement of facial paralysis. The motion information in the horizontal and vertical directions and the appearance features on the apex frames are extracted based on the local binary patterns (LBPs) on the temporal-spatial domain in each facial region. These features are temporally and spatially enhanced by the application of novel block processing schemes. A multiresolution extension of uniform LBP is proposed to efficiently combine the micropatterns and large-scale patterns into a feature vector. The symmetry of facial movements is measured by the resistor-average distance (RAD) between LBP features extracted from the two sides of the face. Support vector machine is applied to provide quantitative evaluation of facial paralysis based on the House-Brackmann (H-B) scale. The proposed method is validated by experiments with 197 subject videos, which demonstrates its accuracy and efficiency.


Asunto(s)
Cara/fisiopatología , Parálisis Facial/fisiopatología , Procesamiento de Imagen Asistido por Computador/métodos , Movimiento , Grabación en Video/métodos , Algoritmos , Inteligencia Artificial , Interpretación Estadística de Datos , Humanos , Reproducibilidad de los Resultados
3.
Artículo en Inglés | MEDLINE | ID: mdl-19163791

RESUMEN

This paper presents a novel framework for objective measurement of facial paralysis in biomedial videos. The motion information in the horizontal and vertical directions and the appearance features on the apex frames are extracted based on the Local Binary Patterns (LBP) on the temporal-spatial domain in each facial region. These features are temporally and spatially enhanced by the application of block schemes. A multi-resolution extension of uniform LBP is proposed to efficiently combine the micro-patterns and large-scale patterns into a feature vector, which increases the algorithmic robustness and reduces noise effects while still retaining computational simplicity. The symmetry of facial movements is measured by the Resistor-Average Distance (RAD) between LBP features extracted from the two sides of the face. Support Vector Machine (SVM) is applied to provide quantitative evaluation of facial paralysis based on the House-Brackmann (H-B) Scale. The proposed method is validated by experiments with 197 subject videos, which demonstrates its accuracy and efficiency.


Asunto(s)
Inteligencia Artificial , Parálisis Facial/diagnóstico , Parálisis Facial/fisiopatología , Interpretación de Imagen Asistida por Computador/métodos , Movimiento , Fotograbar/métodos , Grabación en Video/métodos , Algoritmos , Expresión Facial , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador
5.
Otol Neurotol ; 25(5): 791-6, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15354013

RESUMEN

OBJECTIVE: To examine the relationship between growth rate of vestibular schwannomas and the expression of various growth factor receptors. STUDY DESIGN: Retrospective case review of clinical growth rate in conjunction with a histopathologic and immunohistochemical reexamination of archival specimens. SETTING: A tertiary referral neurotologic center. PATIENTS: Three groups: a historical group to act as controls, consisting of 30 patients with sporadic vestibular schwannomas removed before the unit adopted an initial interval scan policy; a group of 14 patients with sporadic vestibular schwannomas who had undergone an initial interval scan policy, showed radiologic evidence of growth, and therefore had their schwannoma removed; and a group of 16 schwannomas removed from 11 neurofibromatosis Type 2 patients. MAIN OUTCOME MEASURES: A comparison between the three clinical groups using immunohistochemical studies to determine the level of expression of the proliferation factor Ki-67, c-erbB-2, and c-erbB-3 receptors and fibroblastic growth factor receptors 1 and 4. RESULTS: The level of expression of the proliferation factor Ki-67 was very low and similar in all three groups. C-erbB-2 and c-erbB-3 receptors were not expressed in any of the groups. fibroblastic growth factor receptor 4 expression was not significantly different, but there was a variation in the expression of fibroblastic growth factor receptor 1 between the three groups that correlated well with the differing incidence of growth in the groups. The increase in expression of fibroblastic growth factor receptor 1 in the neurofibromatosis Type 2 group was not statistically significant, but the increase in expression of fibroblastic growth factor receptor 1 in the growing sporadic group was statistically significant when compared with the historical controls. The level of fibroblastic growth factor receptor 1 expression correlates significantly with the rate of growth as measured on interval magnetic resonance imaging. CONCLUSIONS: Overexpression of fibroblastic growth factor receptor 1 has a positive correlation with the incidence and the rate of growth of sporadic vestibular schwannomas.


Asunto(s)
Neuroma Acústico/patología , Receptores de Factores de Crecimiento/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Neurofibromatosis 2/complicaciones , Neuroma Acústico/metabolismo , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptor ErbB-3/genética , Receptor ErbB-3/metabolismo , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos , Receptor Tipo 4 de Factor de Crecimiento de Fibroblastos , Receptores de Factores de Crecimiento de Fibroblastos/genética , Receptores de Factores de Crecimiento de Fibroblastos/metabolismo , Receptores de Factores de Crecimiento/genética , Estudios Retrospectivos
6.
Clin Radiol ; 57(5): 355-8, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12014931

RESUMEN

AIM: Intralabyrinthine schwannomas (ILS) are rare benign tumours. They are not always recognized on routine magnetic resonance imaging (MRI). We aimed to study the clinical presentation and MRI findings in our patients with ILS. MATERIALS AND METHODS: Retrospective analysis of patients with vestibular schwannomas treated at this center. RESULTS: Of 144 vestibular schwannomas studied at this centre, three patients had an ILS. The most common presenting symptoms were unilateral hearing loss, tinnitus and vertigo. Two patients demonstrated a progressive sensorineural hearing loss (SNHL). The third patient had a severe SNHL at presentation. MRI enhanced with contrast medium was positive in the two patients with progressive SNHL and negative in the patient with the severe SNHL. CONCLUSION: This series demonstrates the ability of MRI to identify schwannomas filling the labyrinth, and also its inability to identify extremely small ILS. It underlines the importance of sending the cristae of patients undergoing labyrinthectomy for presumed Ménière's disease for histological examination.


Asunto(s)
Neoplasias del Oído/diagnóstico , Enfermedades del Laberinto/diagnóstico , Imagen por Resonancia Magnética , Neurilemoma/diagnóstico , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Enfermedad de Meniere/diagnóstico , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad
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