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1.
J Craniofac Surg ; 30(8): 2560-2564, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31689731

RESUMEN

BACKGROUND: This study aimed to analyze 3-dimensional nasolabial soft tissue changes following double jaw surgery with Le Fort I maxillary advancement and relate them to underlying surgical movements. METHODS: Pre- and post-surgical cone-beam computed tomography images of 37 maxillomandibular surgery patients with ≥2 mm of advancement at A-point were analyzed. Lateral cephalograms were constructed to determine horizontal and vertical surgical movements and 3-dimensional facial images were created from the CBCTs to calculate linear and angular changes. RESULTS: Alar base width increased 1.9 mm, nasal tip protrusion decreased 0.74 mm, the upper lip flattened 7.71 degree and increased 0.9 mm in length, nasal tip was displaced 2.47 mm superiorly causing an increased concavity of 5.52 degree for the overall dorsal surface and 3.99 degree at the supratip break angle (SBA), nasal tip angle decreased 2.16 degree and nasolabial angle decreased 7.37 degree. Correlations were found between underlying surgical movements and nasal tip protrusion, SBA, nasolabial angle (NLA), and nasal tip elevation (NTE). Multiple linear regression equations were calculated to predict changes in SBA from horizontal change at A-point, NLA from horizontal change at B-point, and NTE from the change at A-point horizontally and U1-tip vertically. CONCLUSION: Double jaw surgery with maxillary advancement has significant effects on nasolabial anatomy.


Asunto(s)
Procedimientos Quirúrgicos Ortognáticos , Adolescente , Adulto , Tomografía Computarizada de Haz Cónico , Cara/anatomía & histología , Femenino , Humanos , Imagenología Tridimensional/métodos , Masculino , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Persona de Mediana Edad , Adulto Joven
2.
Am J Orthod Dentofacial Orthop ; 153(6): 895-904, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29853247

RESUMEN

INTRODUCTION: The purpose of this study was to analyze pharyngeal airflow using both computational fluid dynamics (CFD) and fluid structure interactions (FSI) in obstructive sleep apnea patients before and after maxillomandibular advancement (MMA) surgery. The airflow characteristics before and after surgery were compared with both CFD and FSI. In addition, the presurgery and postsurgery deformations of the airway were evaluated using FSI. METHODS: Digitized pharyngeal airway models of 2 obstructive sleep apnea patients were generated from cone-beam computed tomography scans before and after MMA surgery. CFD and FSI were used to evaluate the pharyngeal airflow at a maximum inspiration rate of 166 ml per second. Standard steady-state numeric formulations were used for airflow simulations. RESULTS: Airway volume increased, pressure drop decreased, maximum airflow velocity decreased, and airway resistance dropped for both patients after the MMA surgery. These findings occurred in both the CFD and FSI simulations. The FSI simulations showed an area of marked airway deformation in both patients before surgery, but this deformation was negligible after surgery for both patients. CONCLUSIONS: Both CFD and FSI simulations produced airflow results that indicated less effort was needed to breathe after MMA surgery. The FSI simulations demonstrated a substantial decrease in airway deformation after surgery. These beneficial changes positively correlated with the large improvements in polysomnography outcomes after MMA surgery.


Asunto(s)
Avance Mandibular , Maxilar/cirugía , Apnea Obstructiva del Sueño/fisiopatología , Humanos , Hidrodinámica , Faringe , Proyectos Piloto , Estudios Retrospectivos
3.
Am J Orthod Dentofacial Orthop ; 153(1): 46-53, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29287649

RESUMEN

INTRODUCTION: In this study, we investigated volumetric and dimensional changes to the pharyngeal airway space after isolated mandibular setback surgery for patients with Class III skeletal dysplasia. METHODS: Records of 28 patients who had undergone combined orthodontic and mandibular setback surgery were obtained. The sample comprised 17 men and 11 women. Their mean age was 23.88 ± 6.57 years (range, 18-52 years). Cone-beam computed tomography scans were obtained at 3 time points: before surgery, average of 6 months after surgery, and average of 1 year after surgery. Oropharyngeal, hypopharyngeal, and total volumes were calculated. The lateral surface and anteroposterior dimensions at the minimal axial areas for oropharyngeal and hypopharyngeal volumes and mean mandibular setback were determined. RESULTS: The mean mandibular setback was 9.93 ± 5.26 mm. Repeated measures analysis of variance determined an overall significant decrease between the means for 6 months and up to 1 year after surgery for oropharyngeal and hypopharyngeal volumes, anteroposterior at oropharyngeal, lateral surface at oropharyngeal, and anteroposterior at hypopharyngeal. No strong correlation between mandibular setback surgery and pharyngeal airway volumes or dimensions was determined. CONCLUSIONS: After mandibular setback surgery, pharyngeal airway volume, and transverse and anteroposterior dimensions were decreased. Patients undergoing mandibular setback surgery should be evaluated for obstructive sleep apnea and the proposed treatment plan modified according to the risk for potential airway compromise.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Maloclusión de Angle Clase III/cirugía , Mandíbula/cirugía , Procedimientos Quirúrgicos Ortognáticos/métodos , Faringe/anatomía & histología , Faringe/diagnóstico por imagen , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
4.
J Oral Maxillofac Surg ; 74(6): 1215-27, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26878364

RESUMEN

PURPOSE: To measure and identify factors associated with treatment outcomes for patients with temporomandibular joint (TMJ) ankylosis treated with TMJ Concepts patient-fitted total joint prostheses and autogenous fat grafts. PATIENTS AND METHODS: This retrospective cohort study evaluated records of patients with TMJ ankylosis from a single private practice, treated from 1992 to 2011, who met the following inclusion criteria: 1) radiographic evidence of bony ankylosis, 2) limited incisal opening, 3) minimum of 12 months' follow-up, and 4) treatment with TMJ Concepts (Ventura, CA)/Techmedica (Camarillo, CA) total joint prostheses and fat grafts. For each patient, the number of previous TMJ surgical procedures, as well as the estimated age of ankylosis onset, age at surgery, and length of postoperative follow-up, was recorded. Subjective evaluations were made with Likert-like scales (from 0 to 10) for 1) TMJ pain, 2) headache and facial pain, 3) jaw function, 4) diet, and 5) disability. Objective evaluations included maximal incisal opening and excursion movements. Nonparametric statistics were used for analysis. RESULTS: There were 32 patients (22 female and 10 male patients) with 48 ankylosed TMJs (16 bilateral and 16 unilateral) in this study, with a mean age of 39 years (range, 11 to 68 years), 2 or more previous TMJ surgical procedures in 69%, and a mean follow-up period of 68 months (range, 12 to 168 months). Trauma was the major etiology of TMJ ankylosis, occurring in 17 of 32 patients (53%). The following improvements occurred: The median value for TMJ pain changed from 8.0 preoperatively to 1.5 at longest follow-up; headache, from 8 to 3.5; facial pain, from 8 to 4; jaw function, from 8 to 2.5; diet, from 7 to 3; and disability, from 7 to 1.5. The median incisal opening was 14.5 mm (interquartile range, 6.3 to 20 mm) preoperatively and 35 mm (interquartile range, 30 to 40 mm) at longest follow-up. The median left lateral excursion improved from 0.5 to 2 mm, and the median right lateral excursion improved from 1 to 1.3 mm. All of these improvements were highly significant (P < .001, Wilcoxon tests). Equally favorable outcomes were found in patients with 12 to 48 months of maximal follow-up and patients with more than 48 months of maximal follow-up. CONCLUSIONS: The treatment of TMJ ankylosis with the TMJ Concepts patient-fitted total joint prosthesis in combination with fat grafting around the articulation area of the prosthesis is a viable and predictable method for improving pain levels, function, and quality of life, as well as prevention of reankylosis of the TMJ.


Asunto(s)
Anquilosis/cirugía , Artroplastia de Reemplazo , Trastornos de la Articulación Temporomandibular/cirugía , Tejido Adiposo/trasplante , Adolescente , Adulto , Anciano , Artroplastia de Reemplazo/métodos , Niño , Femenino , Humanos , Prótesis Articulares , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Trasplante de Tejidos/métodos , Adulto Joven
5.
J Oral Maxillofac Surg ; 74(8): 1539-47, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26988573

RESUMEN

PURPOSE: The purpose of this study was to evaluate patients requiring unilateral total temporomandibular joint (TMJ) reconstruction and the risk for development of postsurgical contralateral TMJ pain and dysfunction over time requiring subsequent contralateral total joint reconstruction. Long-term subjective and objective outcomes of unilateral TMJ reconstruction also were evaluated. MATERIALS AND METHODS: Seventy patients underwent unilateral total joint reconstruction using a patient-fitted total joint prosthesis from a single private practice from 1990 through 2012. The inclusion criteria were 1) unilateral TMJ reconstruction with TMJ Concepts or Techmedica patient-fitted total joint prosthesis; 2) operation performed by 1 surgeon (L.M.W.); 3) minimum 12-month follow-up; and 4) adequate records. There were no specific exclusion criteria. The primary outcome variable was to evaluate the effects of unilateral TMJ reconstruction with a total joint prosthesis on the contralateral TMJ relative to development of pain and dysfunction requiring subsequent contralateral reconstruction with a total joint prosthesis. Secondary outcome variables for all patients included TMJ pain, facial pain, headaches, diet, disability, quality of life, maximum incisal opening (MIO), and lateral excursion movements after unilateral TMJ reconstruction with the patient-fitted total joint prosthesis. Student t test and Wilcoxon test were used for statistical analyses, with a P value less than .01 for statistical significance. RESULTS: Sixty-one of 70 patients (87%) met the inclusion criteria (47 women [77%] and 14 men [23%]; average age, 38 yr; age range, 11 to 69 yr; average follow-up, 44 months; range, 12 to 215 months). Eight of 61 patients (13%) subsequently required contralateral TMJ reconstruction with a total joint prosthesis related to contralateral pain, dysfunction, and arthritis, but all 8 (8 of 27 [29.6%]) had previous contralateral TMJ disc repositioning surgery. For the secondary outcomes, TMJ pain decreased 63%, jaw function improved 61%, facial pain decreased 59%, headaches decreased 57%, diet improved 52%, disability decreased 58.5%, and MIO increased from 31.4 to 38.8 mm (mean change, 7.4 mm). All subjective factors and MIO showed statistically significant improvements at longest follow-up (P < .01). CONCLUSIONS: Patients requiring unilateral TMJ reconstruction with a patient-fitted total joint prosthesis have a strong probability of improving their clinical condition and do not require bilateral reconstruction if the contralateral TMJ is healthy. Patients with previous or concomitant contralateral TMJ surgery (articular disc repositioning) have an approximately 30% chance of requiring a total joint prosthesis in the future.


Asunto(s)
Artralgia/etiología , Artroplastia de Reemplazo , Dolor Facial/etiología , Prótesis Articulares , Complicaciones Posoperatorias/etiología , Falla de Prótesis/etiología , Articulación Temporomandibular/cirugía , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Reoperación , Factores de Riesgo , Factores de Tiempo
6.
J Oral Maxillofac Surg ; 73(5): 952-60, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25631865

RESUMEN

PURPOSE: To evaluate subjective and objective outcomes of patients receiving Techmedica (currently TMJ Concepts) patient-fitted temporomandibular joint (TMJ) total joint replacement (TJR) devices after 19 to 24 years of service. PATIENTS AND METHODS: This prospective cohort study evaluated 111 patients operated on by 2 surgeons using Techmedica (Camarillo, CA) patient-fitted TMJ TJR devices from November 1989 to July 1993. Patients were evaluated before surgery and at least 19 years after surgery. Subjective evaluations used standard forms and questions with a Likert scale for 1) TMJ pain (0, no pain; 10, worst pain imaginable), 2) jaw function (0, normal function; 10, no movement), 3) diet (0, no restriction; 10, liquid only), and 4) quality of life (QoL; improved, the same, or worse). Objective assessment measured maximum incisal opening (MIO). Comparison analysis of presurgical and longest follow-up data used nonparametric Mann-Whitney and Wilcoxon signed rank tests. Spearman correlations evaluated the number of prior surgeries in relation to objective and subjective variables. RESULTS: Of the 111 patients, 56 (50.5%) could be contacted and had adequate records for inclusion in the study. Median follow-up was 21 years (interquartile range [IQR], 20 to 22 yr). Mean age at surgery was 38.6 years (standard deviation, 10 yr). Median number of previous TMJ surgeries was 3 (IQR, 4). Presurgical and longest follow-up data comparison showed statistically significant improvement (P < .001) for MIO, TMJ pain, jaw function, and diet. At longest follow-up, 48 patients reported improved QoL, 6 patients reported the same QoL, and 2 patients reported worse QoL. Spearman correlations showed that an increased number of previous surgeries resulted in lower levels of improvement for TMJ pain and MIO. CONCLUSIONS: At a median of 21 years after surgery, the Techmedica/TMJ Concepts TJR continued to function well. More previous TMJ surgeries indicated a lesser degree of improvement. No devices were removed owing to material wear.


Asunto(s)
Prótesis Mandibular , Trastornos de la Articulación Temporomandibular/cirugía , Adulto , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Calidad de Vida , Trastornos de la Articulación Temporomandibular/fisiopatología
7.
J Oral Maxillofac Surg ; 72(3): 567-95, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24388179

RESUMEN

A classification system was developed to place patients with condylar hyperplasia (CH) into categories based on histology, clinical and imaging characteristics, effects on the jaws and facial structures, and rate of occurrence. Four major categories were defined. CH type 1 is an accelerated and prolonged growth aberration of the "normal" mandibular condylar growth mechanism, causing a predominantly horizontal growth vector, resulting in prognathism that can occur bilaterally (CH type 1A) or unilaterally (CH type 1B). CH type 2 refers to enlargement of the mandibular condyle caused by an osteochondroma, resulting in predominantly unilateral vertical overgrowth and elongation of the mandible and face. One of the forms has predominantly a vertical growth vector and condylar enlargement, but without exophytic tumor extensions (type 2A), whereas the other primary form grows vertically but develops horizontal exophytic tumor growth off of the condyle (CH type 2B). CH type 3 includes other rare, benign tumors and CH type 4 includes malignant conditions that originate in the mandibular condyle causing enlargement. The order of classification is based on occurrence rates and type of pathology, where CH type 1A is the most commonly occurring form and CH type 4 is the rarest. This classification system for CH pathology should help the clinician understand the nature of the pathology, progression if untreated, recommended ages for surgical intervention to minimize adverse effects on subsequent facial growth and development in younger patients, and the surgical protocols to comprehensively and predictably treat these conditions.


Asunto(s)
Cóndilo Mandibular/anomalías , Enfermedades Mandibulares/clasificación , Osteotomía Mandibular , Prognatismo/clasificación , Prognatismo/etiología , Adolescente , Factores de Edad , Edad de Inicio , Cefalometría , Femenino , Humanos , Hiperplasia/clasificación , Hiperplasia/etiología , Hiperplasia/cirugía , Masculino , Cóndilo Mandibular/diagnóstico por imagen , Cóndilo Mandibular/cirugía , Neoplasias Mandibulares/complicaciones , Neoplasias Mandibulares/cirugía , Desarrollo Maxilofacial , Procedimientos Quirúrgicos Ortognáticos , Osteocondroma/complicaciones , Radiografía , Dimensión Vertical
8.
J Oral Maxillofac Surg ; 72(9): 1704-28, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24997022

RESUMEN

PURPOSE: To evaluate the outcomes from surgical treatment of mandibular condylar osteochondroma (condylar hyperplasia [CH] type 2) using a specific surgical protocol. CH type 2 is a unilateral benign pathologic condition, with progressive proliferation of osseous and cartilaginous tissues in the condylar head. This causes condylar enlargement, often with exophytic growth, resulting in significant facial deformity, pain, and masticatory and occlusal dysfunction. PATIENTS AND METHODS: This was a retrospective cohort study of 37 patients (28 females and 9 males), with an average age of 26.3 years (range 13 to 48), with CH type 2, and associated dentofacial deformity. The condylar pathologic features were confirmed by histologic analysis. All patients were treated with low condylectomy, recontouring of the condylar neck to form a new condyle, repositioning of the articular disc over the condylar stump and repositioning of the contralateral disc, if displaced, and any indicated orthognathic surgical procedures. Postoperative follow-up averaged 48 months (range 12 to 288). Patients were assessed preoperatively and at the longest follow-up point for incisal opening, lateral excursions, pain, jaw function, diet, disability, and occlusal and skeletal stability. The pre- and postoperative assessments were compared using paired t test. RESULTS: At the longest follow-up point, a nonsignificant decrease (2.3 mm) was seen in the maximum incisal opening; however, the excursive movements had decreased significantly an average of 2.5 mm on the right and 2.2 mm on the left. A statistically significant improvement was seen in pain, jaw function, diet, and disability. A stable Class I skeletal and occlusal relationship was maintained in 34 of the 37 patients (92%). Two patients developed relatively minor postoperative malocclusions that were managed with orthodontics. In 1 patient, a high condylectomy was performed, and the tumor continued to grow, causing malocclusion and jaw deformity to recur. A low condylectomy and sagittal split were performed 14 months later, with a stable result at 4 years after surgery. CONCLUSIONS: The results of the present study have demonstrated that a low condylectomy procedure with recontouring of the condylar neck to function as a condyle and repositioning of the articular discs, combined with orthognathic surgery, is a viable option for the treatment of osteochondroma of the mandibular condyle and associated jaw deformity.


Asunto(s)
Cóndilo Mandibular/cirugía , Neoplasias Mandibulares/cirugía , Procedimientos Quirúrgicos Ortognáticos/métodos , Osteocondroma/cirugía , Adolescente , Adulto , Cartílago Articular/cirugía , Estudios de Cohortes , Oclusión Dental , Dieta , Asimetría Facial/cirugía , Dolor Facial/etiología , Femenino , Estudios de Seguimiento , Humanos , Hiperplasia , Masculino , Maloclusión/etiología , Cóndilo Mandibular/patología , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico , Calidad de Vida , Rango del Movimiento Articular/fisiología , Estudios Retrospectivos , Disco de la Articulación Temporomandibular/cirugía , Resultado del Tratamiento , Adulto Joven
9.
J Oral Maxillofac Surg ; 71(12): 2123-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24128705

RESUMEN

Clinicians who address temporomandibular joint (TMJ) pathology and dentofacial deformities surgically can perform the surgery in 1 stage or 2 separate stages. The 2-stage approach requires the patient to undergo 2 separate operations and anesthesia, significantly prolonging the overall treatment. However, performing concomitant TMJ and orthognathic surgery (CTOS) in these cases requires careful treatment planning and surgical proficiency in the 2 surgical areas. This article presents a new treatment protocol for the application of computer-assisted surgical simulation in CTOS cases requiring reconstruction with patient-fitted total joint prostheses. The traditional and new CTOS protocols are described and compared. The new CTOS protocol helps decrease the preoperative workup time and increase the accuracy of model surgery.


Asunto(s)
Artroplastia de Reemplazo/métodos , Deformidades Dentofaciales/cirugía , Procedimientos Quirúrgicos Ortognáticos/métodos , Cirugía Asistida por Computador , Trastornos de la Articulación Temporomandibular/cirugía , Articulación Temporomandibular/cirugía , Cefalometría , Protocolos Clínicos , Simulación por Computador , Deformidades Dentofaciales/complicaciones , Humanos , Modelos Anatómicos , Tempo Operativo , Cirugía Asistida por Computador/métodos , Trastornos de la Articulación Temporomandibular/complicaciones , Factores de Tiempo
10.
J Oral Maxillofac Surg ; 71(1): 178-88, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22705221

RESUMEN

PURPOSE: Metastasis to the maxillofacial region is a rare occurrence. In our retrospective study of patients with metastasis to the maxillofacial region, the subjects were evaluated to define the clinical behavior patterns in response to the treatment given. MATERIALS AND METHODS: A retrospective record review during a 15-year period (1990 to 2005) was conducted. The patients were selected for inclusion in the present study if they had histologically confirmed maxillofacial metastases. RESULTS: In our retrospective study, during the 15-year period, 1,221 new patients with maxillofacial/oral cancer were seen and evaluated. Of these 1,221 patients, 26 (16 men and 10 women) were identified as having a histologically confirmed metastasis to the maxillofacial region, for an incidence of 2.1%. CONCLUSIONS: Patients with metastasis to the maxillofacial region are often deemed to not be surgical candidates because of the extensive nature of the metastatic disease. We believe that surgical intervention plays a beneficial role in improving quality of life in a properly selected group of patients with metastasis to the maxillofacial region. In our case series, surgery was performed in about 50% of the patients, and palliation and radiotherapy were the most commonly used modalities.


Asunto(s)
Neoplasias de Cabeza y Cuello/secundario , Neoplasias de la Boca/secundario , Procedimientos Quirúrgicos Orales/estadística & datos numéricos , Adenocarcinoma/secundario , Anciano , Anciano de 80 o más Años , Algoritmos , Neoplasias de la Mama/patología , Neoplasias del Colon/patología , Irradiación Craneana/estadística & datos numéricos , Femenino , Neoplasias de Cabeza y Cuello/terapia , Hospitales Especializados , Humanos , Neoplasias Maxilomandibulares/secundario , Neoplasias Maxilomandibulares/terapia , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/terapia , Metástasis de la Neoplasia , Cuidados Paliativos/estadística & datos numéricos , Estudios Retrospectivos , Neoplasias de las Glándulas Salivales/secundario , Neoplasias de las Glándulas Salivales/terapia , Resultado del Tratamiento
11.
J Clin Pediatr Dent ; 36(4): 373-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23019835

RESUMEN

The ghost cell odontogenic tumor (GCOT) is a neoplastic/cystic lesion with a diverse histopathological and clinical behavior It was formerly known as calcified odontogenic cyst, but in 2005 the World Health Organization categorized this lesion as an odontogenic, benign tumor rather than a cyst; nominating this neoplasm as calcifying cystic odontogenic tumor. A later comprehensive classification named it ghost cell odontogenic tumor because the most remarkable histopathologic characteristic is the presence of a mass of ghost cells embedded in the epithelium. We report two cases of a rare variant of a ghost cell odontogenic tumor associated with odontoma; to our knowledge, one is the youngest patient (four month old) reported in the English literature.


Asunto(s)
Neoplasias Mandibulares/patología , Neoplasias Primarias Múltiples/patología , Tumores Odontogénicos/patología , Odontoma/patología , Niño , Diagnóstico Diferencial , Femenino , Humanos , Lactante , Enfermedades Raras
12.
Comput Math Methods Med ; 2022: 2014001, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35991131

RESUMEN

Accurate and early diagnosis of mild cognitive impairment (MCI) is necessary to prevent the progress of Alzheimer's and other kinds of dementia. Unfortunately, the symptoms of MCI are complicated and may often be misinterpreted as those associated with the normal ageing process. To address this issue, many studies have proposed application of machine learning techniques for early MCI diagnosis based on electroencephalography (EEG). In this study, a machine learning framework for MCI diagnosis is proposed in this study, which extracts spectral, functional connectivity, and nonlinear features from EEG signals. The sequential backward feature selection (SBFS) algorithm is used to select the best subset of features. Several classification models and different combinations of feature sets are measured to identify the best ones for the proposed framework. A dataset of 16 and 18 EEG data of normal and MCI subjects is used to validate the proposed system. Metrics including accuracy (AC), sensitivity (SE), specificity (SP), F1-score (F1), and false discovery rate (FDR) are evaluated using 10-fold crossvalidation. An average AC of 99.4%, SE of 98.8%, SP of 100%, F1 of 99.4%, and FDR of 0% have been provided by the best performance of the proposed framework using the linear support vector machine (LSVM) classifier and the combination of all feature sets. The acquired results confirm that the proposed framework provides an accurate and robust performance for recognizing MCI cases and outperforms previous approaches. Based on the obtained results, it is possible to be developed in order to use as a computer-aided diagnosis (CAD) tool for clinical purposes.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Enfermedad de Alzheimer/diagnóstico , Disfunción Cognitiva/diagnóstico , Electroencefalografía/métodos , Humanos , Aprendizaje Automático , Imagen por Resonancia Magnética/métodos
13.
Phys Eng Sci Med ; 45(3): 705-719, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35635612

RESUMEN

Major depressive disorder (MDD) as a psychiatric illness negatively affects the behavior and daily life of the patients.Therefore, the early MDD diagnosis can help to cure the patients more efficiently and prevent adverse effects, although its unclear manifestations make the early diagnosis challenging. Nowadays, many studies have proposed automatic early MDD diagnosis methods based on electroencephalogram (EEG) signals. This study also presents an automated EEG-based MDD diagnosis framework based on Dictionary learning (DL) approaches and functional connectivity features. Firstly, a feature space of MDD and healthy control (HC) participants were constructed via functional connectivity features.Next, DL-based classification approaches such as Label Consistent K-SVD (LC-KSVD) and Correlation-based Label Consistent K-SVD (CLC-KSVD) methods, were utilized to perform the classification task. A public dataset was used, consisting of EEG signals from 34 MDD patients and 30 HC subjects, to evaluate the proposed method. To validate the proposed method, 10-fold cross-validation technique with 100 iterations was employed, providing accuracy (AC), sensitivity (SE), specificity (SP), F1-score (F1), and false discovery rate (FDR) performance metrics. The results show that LC-KSVD2 and CLC-KSVD2 performed efficiently in classifying MDD and HC cases. The best classification performance was obtained by the LCKSVD2 method, with average AC of 99.0%, SE of 98.9%, SP of 99.2%, F1 of 99.0%, and FDR of 0.8%. According to the results, the proposed method provides an accurate performance and, therefore, it can be developed into a computer-aided diagnosis (CAD) tool for automatic MDD diagnosis.


Asunto(s)
Trastorno Depresivo Mayor , Trastorno Depresivo Mayor/diagnóstico por imagen , Diagnóstico por Computador/métodos , Electroencefalografía/métodos , Humanos , Aprendizaje
14.
J Oral Maxillofac Surg ; 69(1): 192-8, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21055859

RESUMEN

Schizophrenia is a disorder that affects a significant portion of the population. This case report and review article discusses potential causes and pathophysiology. The treatment of schizophrenia is outlined in detail, followed by a discussion of the perioperative management of schizophrenic patients, highlighting important information to keep in mind when treating this patient population.


Asunto(s)
Esquizofrenia/complicaciones , Adulto , Antipsicóticos/uso terapéutico , Butirofenonas/uso terapéutico , Traumatismos Faciales/etiología , Traumatismos Faciales/cirugía , Frente/lesiones , Fracturas Conminutas/etiología , Fracturas Conminutas/cirugía , Humanos , Laceraciones/etiología , Laceraciones/cirugía , Labio , Masculino , Hueso Nasal/lesiones , Tabique Nasal/lesiones , Fenotiazinas/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/fisiopatología , Conducta Autodestructiva/etiología , Conducta Autodestructiva/cirugía , Fracturas Craneales/etiología , Fracturas Craneales/cirugía , Heridas Penetrantes/etiología , Heridas Penetrantes/cirugía
15.
J Oral Maxillofac Surg ; 69(11): 2924-9, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21549473

RESUMEN

Lymphoma is a common disease of the head and neck. Mucosal-associated lymphoid tissue (MALT) lymphoma constitutes a rare type of extranodal lymphoma. The Waldeyer's ring is one of the most common sites of occurrence, but MALT lymphoma may also arise in salivary glands, lung, stomach, or lacrimal glands. In the oral cavity, it may be confused with swellings from dental infection or sinus inflammation. Often, the patient will seek a dentist because of mobile teeth or because a denture no longer fits. We report a case of a female patient with salivary gland dysfunction and pain of several years' duration, who, after numerous tests and hospitalizations, was diagnosed with Sjögren's syndrome. She later developed mucosal-associated lymphoid tissue lymphoma. We discuss the diagnosis, treatment, and prognosis of this entity. MALT lymphoma is rare in salivary glands. In primary-Sjögren's syndrome, predisposition of the patient for development of malignant non-Hodgkin's lymphoma (4% to 10%) is well established. In this case, long-standing sialadenitis and Sjögren's syndrome seem to be the etiological factors. In cases of chronic infection of salivary glands and the presence of autoimmune syndromes, MALT lymphoma should be considered in the differential diagnosis. Consults should be called to ophthalmology, rheumatology, and head and neck oncologists for proper workup, staging, and treatment.


Asunto(s)
Linfoma de Células B de la Zona Marginal/diagnóstico , Síndrome de Sjögren/diagnóstico , Neoplasias de la Glándula Submandibular/diagnóstico , Adulto , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Sialadenitis/diagnóstico , Enfermedades de la Glándula Submandibular/diagnóstico
17.
J Neurosci Methods ; 358: 109209, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33957158

RESUMEN

BACKGROUND: Major depressive disorder (MDD) is a prevalent mental illness that is diagnosed through questionnaire-based approaches; however, these methods may not lead to an accurate diagnosis. In this regard, many studies have focused on using electroencephalogram (EEG) signals and machine learning techniques to diagnose MDD. NEW METHOD: This paper proposes a machine learning framework for MDD diagnosis, which uses different types of EEG-derived features. The features are extracted using statistical, spectral, wavelet, functional connectivity, and nonlinear analysis methods. The sequential backward feature selection (SBFS) algorithm is also employed to perform feature selection. Various classifier models are utilized to select the best one for the proposed framework. RESULTS: The proposed method is validated with a public EEG dataset, including the EEG data of 34 MDD patients and 30 healthy subjects. The evaluation of the proposed framework is conducted using 10-fold cross-validation, providing the metrics such as accuracy (AC), sensitivity (SE), specificity (SP), F1-score (F1), and false discovery rate (FDR). The best performance of the proposed method has provided an average AC of 99%, SE of 98.4%, SP of 99.6%, F1 of 98.9%, and FDR of 0.4% using the support vector machine with RBF kernel (RBFSVM) classifier. COMPARISON WITH EXISTING METHODS: The obtained results demonstrate that the proposed method outperforms other approaches for MDD classification based on EEG signals. CONCLUSIONS: According to the obtained results, a highly accurate MDD diagnosis would be provided using the proposed method, while it can be utilized to develop a computer-aided diagnosis (CAD) tool for clinical purposes.


Asunto(s)
Trastorno Depresivo Mayor , Algoritmos , Trastorno Depresivo Mayor/diagnóstico , Electroencefalografía , Humanos , Aprendizaje Automático , Máquina de Vectores de Soporte , Análisis de Ondículas
18.
Comput Biol Med ; 109: 242-253, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31096088

RESUMEN

Accurate segmentation of the sperms in microscopic semen smear images is a prerequisite step in automatic sperm morphology analysis. It is a challenging task due to the non-uniform distribution of light in semen smear images, low contrast between sperm's tail and its surrounding region, the existence of various artifacts, high concentration of sperms and wide spectrum of the shapes of the sperm's parts. This paper proposes an automatic framework based on concatenated learning approaches to segment the external and internal parts of the sperms. The external parts of the sperms are segmented using two convolutional neural network (CNN) models which produce the probability maps of the head and the axial filament regions. To obtain acrosome and nucleus segments, the K-means clustering approach is applied to the head segments. A Support Vector Machine (SVM) classifier is used to classify each pixel of the axial filament segments to extract tail and mid-piece regions from obtained segments. The proposed method is validated on the images of the Gold-standard dataset. It achieves 0.90, 0.77, 0.77, 0.78, 0.75 and 0.64 of the average of dice similarity coefficient for the head, axial filament, acrosome, nucleus, tail, and mid-piece segments, respectively. Experimental results demonstrate that the proposed method outperforms state-of-the-art algorithms for the head and its internal parts segmentation. It also segments the axial filament region and its internal parts with desirable accuracy. Different from previous works, the proposed method is able to segment all parts of the sperms which enables automatic quantitative analysis of the sperm morphology.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Análisis de Semen , Espermatozoides/citología , Máquina de Vectores de Soporte , Humanos , Masculino , Microscopía
20.
Angle Orthod ; 86(6): 976-982, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27120198

RESUMEN

OBJECTIVE: To analyze and compare pharyngeal airflow characteristics pre- and post-mandibular setback surgery in patients with Class III skeletal dysplasia using cone beam computed tomography (CBCT) and computational fluid dynamics (CFD). MATERIALS AND METHODS: Records of 29 patients who had received orthodontic treatment along with mandibular setback surgery were obtained. CBCT scans were obtained at three time points: T1 (before surgery), T2 (average of 6 months after surgery), and T3 (average of 1 year after surgery). Digitized pharyngeal airway models were generated from these scans. CFD was used to simulate and characterize pharyngeal airflow. RESULTS: Mean airway volume was significantly reduced from 35,490.324 mm3 at T1 to 24,387.369 mm3 at T2 and 25,069.459 mm3 at T3. Significant increase in mean negative pressure was noted from 3.110 Pa at T1 to 6.116 Pa at T2 and 6.295 Pa at T3. There was a statistically significant negative correlation between the change in airway volume and the change in pressure drop at both the T2 and T3 time points. There was a statistically significant negative correlation between the amount of mandibular setback and change in pressure drop at the T2 time point. CONCLUSIONS: Following mandibular setback surgery, pharyngeal airway volume was decreased and relative mean negative pressure was increased, implying an increased effort required from a patient for maintaining constant pharyngeal airflow. Thus, high-risk patients undergoing a large amount of mandibular setback surgery should be evaluated for obstructive sleep apnea and the proposed treatment plan be revised based on the risk for potential airway compromise.


Asunto(s)
Hidrodinámica , Maloclusión de Angle Clase III/cirugía , Faringe/anatomía & histología , Adolescente , Adulto , Cefalometría , Tomografía Computarizada de Haz Cónico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Mandíbula , Persona de Mediana Edad , Adulto Joven
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