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1.
Heliyon ; 10(1): e23252, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38148822

RESUMEN

Sign language recognition (SLR) contains the capability to convert sign language gestures into spoken or written language. This technology is helpful for deaf persons or hard of hearing by providing them with a way to interact with people who do not know sign language. It is also be utilized for automatic captioning in live events and videos. There are distinct methods of SLR comprising deep learning (DL), computer vision (CV), and machine learning (ML). One general approach utilises cameras for capturing the signer's hand and body movements and processing the video data for recognizing the gestures. One of challenges with SLR comprises the variability in sign language through various cultures and individuals, the difficulty of certain signs, and require for realtime processing. This study introduces an Automated Sign Language Detection and Classification using Reptile Search Algorithm with Hybrid Deep Learning (SLDC-RSAHDL). The presented SLDC-RSAHDL technique detects and classifies different types of signs using DL and metaheuristic optimizers. In the SLDC-RSAHDL technique, MobileNet feature extractor is utilized to produce feature vectors, and its hyperparameters can be adjusted by manta ray foraging optimization (MRFO) technique. For sign language classification, the SLDC-RSAHDL technique applies HDL model, which incorporates the design of Convolutional Neural Network (CNN) and Long-Short Term Memory (LSTM). At last, the RSA was exploited for the optimal hyperparameter selection of the HDL model, which resulted in an improved detection rate. The experimental result analysis of the SLDC-RSAHDL technique on sign language dataset demonstrates the improved performance of the SLDC-RSAHDL system over other existing DL techniques.

2.
Cancers (Basel) ; 14(22)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36428752

RESUMEN

Gastric cancer (GC) diagnoses using endoscopic images have gained significant attention in the healthcare sector. The recent advancements of computer vision (CV) and deep learning (DL) technologies pave the way for the design of automated GC diagnosis models. Therefore, this study develops a new Manta Ray Foraging Optimization Transfer Learning technique that is based on Gastric Cancer Diagnosis and Classification (MRFOTL-GCDC) using endoscopic images. For enhancing the quality of the endoscopic images, the presented MRFOTL-GCDC technique executes the Wiener filter (WF) to perform a noise removal process. In the presented MRFOTL-GCDC technique, MRFO with SqueezeNet model is used to derive the feature vectors. Since the trial-and-error hyperparameter tuning is a tedious process, the MRFO algorithm-based hyperparameter tuning results in enhanced classification results. Finally, the Elman Neural Network (ENN) model is utilized for the GC classification. To depict the enhanced performance of the presented MRFOTL-GCDC technique, a widespread simulation analysis is executed. The comparison study reported the improvement of the MRFOTL-GCDC technique for endoscopic image classification purposes with an improved accuracy of 99.25%.

3.
Biology (Basel) ; 11(8)2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-36009847

RESUMEN

Epileptic seizures are a chronic and persistent neurological illness that mainly affects the human brain. Electroencephalogram (EEG) is considered an effective tool among neurologists to detect various brain disorders, including epilepsy, owing to its advantages, such as its low cost, simplicity, and availability. In order to reduce the severity of epileptic seizures, it is necessary to design effective techniques to identify the disease at an earlier stage. Since the traditional way of diagnosing epileptic seizures is laborious and time-consuming, automated tools using machine learning (ML) and deep learning (DL) models may be useful. This paper presents an intelligent deep canonical sparse autoencoder-based epileptic seizure detection and classification (DCSAE-ESDC) model using EEG signals. The proposed DCSAE-ESDC technique involves two major processes, namely, feature selection and classification. The DCSAE-ESDC technique designs a novel coyote optimization algorithm (COA)-based feature selection technique for the optimal selection of feature subsets. Moreover, the DCSAE-based classifier is derived for the detection and classification of different kinds of epileptic seizures. Finally, the parameter tuning of the DSCAE model takes place via the krill herd algorithm (KHA). The design of the COA-based feature selection and KHA-based parameter tuning shows the novelty of the work. For examining the enhanced classification performance of the DCSAE-ESDC technique, a detailed experimental analysis was conducted using a benchmark epileptic seizure dataset. The comparative results analysis portrayed the better performance of the DCSAE-ESDC technique over existing techniques, with maximum accuracy of 98.67% and 98.73% under binary and multi-classification, respectively.

4.
Eur J Cancer ; 153: 242-256, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34256319

RESUMEN

BACKGROUND: Radical (chemo)radiotherapy offers potentially curative treatment for patients with locally advanced laryngeal or hypopharyngeal cancer. We aimed to show that dose-escalated intensity-modulated radiotherapy (DE-IMRT) improved locoregional control. METHODS: We performed a phase III open-label randomised controlled trial in patients with laryngeal or hypopharyngeal cancer (AJCC III-IVa/b, TNM 7). Patients were randomised (1:1) to DE-IMRT or standard dose IMRT (ST-IMRT) using a minimisation algorithm, balancing for centre, tumour site, nodal status and chemotherapy use. DE-IMRT was 67.2 gray (Gy) in 28 fractions (f) to the primary tumour and 56Gy/28f to at-risk nodes; ST-IMRT was 65Gy/30f to primary tumour and 54Gy/30f to at-risk nodes. Suitable patients received 2 cycles of concomitant cisplatin and up to 3 cycles of platinum-based induction chemotherapy. The primary end-point was time to locoregional failure analysed by intention-to-treat analysis using competing risk methodology. FINDINGS: Between February 2011 and October 2015, 276 patients (138 ST-IMRT; 138 DE-IMRT) were randomised. A preplanned interim futility analysis met the criterion for early closure. After a median follow-up of 47.9 months (interquartile range 37.5-60.5), there were locoregional failures in 38 of 138 (27.5%) ST-IMRT patients and 42 of 138 (30.4%) DE-IMRT patients; an adjusted subhazard ratio of 1.16 (95% confidence interval: 0.74-1.83, p = 0.519) indicated no evidence of benefit with DE-IMRT. Acute grade 2 pharyngeal mucositis was reported more frequently with DE-IMRT than with ST-IMRT (42% vs. 32%). No differences in grade ≥3 acute or late toxicity rates were seen. CONCLUSION: DE-IMRT did not improve locoregional control in patients with laryngeal or hypopharyngeal cancer. The trial is registered: ISRCTN01483375.


Asunto(s)
Neoplasias Hipofaríngeas/radioterapia , Neoplasias Laríngeas/radioterapia , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
5.
Clin Otolaryngol ; 45(6): 847-852, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32501648

RESUMEN

OBJECTIVES: Target volumes for irradiation remain ill-defined for squamous cell cancer of unknown primary in the head and neck (SCCUP). The aim of this study was to compare involved neck only (INO) radiotherapy (RT) with irradiating involved neck plus potential mucosal primary sites and contralateral neck (MUC) in patients diagnosed and treated with modern diagnostics and techniques. DESIGN: This is a retrospective cohort study. Patients with a diagnosis of SCCUP with unilateral neck disease were included. RESULTS: Thirty patients were identified. All underwent FDG PET-CT. 47% of patients had HPV-positive SCC. 20 patients received RT to INO, 10 patients to MUC, all with volumetric modulated arc therapy (VMAT). A significantly lower dose for each organ at risk was delivered in INO-treated patients, with mean dose to contralateral parotid gland 57% less. The proportion of patients with late grade 2 or worse xerostomia was higher in MUC patients. The incidence of grade 2-3 mucositis (89% vs 45%) and grade 3 or worse dysphagia (50% vs 10%) was higher in MUC patients. Median follow-up was 31 months. No mucosal primaries emerged. Progression-free survival at 2 years was 74.7% for INO patients, 70% in the MUC group. Overall survival at 2 years was 79.7% in the INO group and 70% in the MUC patients. CONCLUSION: INO radiotherapy for patients with SCCUP of the head and neck is a safe treatment strategy resulting in clinically significant lower RT doses to OARS. Acute and late toxicities are reduced without detriment to patient survival.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeza y Cuello/radioterapia , Neoplasias Primarias Desconocidas/radioterapia , Radioterapia de Intensidad Modulada , Anciano , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/mortalidad , Femenino , Fluorodesoxiglucosa F18 , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Mucositis/etiología , Neoplasias Primarias Desconocidas/diagnóstico por imagen , Neoplasias Primarias Desconocidas/mortalidad , Órganos en Riesgo , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos , Estudios Retrospectivos , Tasa de Supervivencia , Xerostomía/etiología
6.
Oral Oncol ; 97: 76-81, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31437587

RESUMEN

OBJECTIVES: Surveillance PET-CT scans at 12 weeks post-radiotherapy for head and neck cancer can be used to omit neck dissections with no detriment in overall survival. Human Papillomavirus (HPV) driven tumours behave differently on conventional imaging after radiotherapy but it is unknown if this effect is seen on PET-CT and if HPV status affects the accuracy of PET-CT. We aimed to determine the negative and positive predictive values (NPV and PPV) of 12 week surveillance PET-CT in HPV positive and negative tumours, and investigate predictors of relapse in equivocal responders. MATERIALS AND METHODS: A retrospective cohort study in a UK tertiary level oncology hospital, between 2013 and 2016 included adults with oropharyngeal squamous cell carcinoma, or HPV positive head and neck squamous cell cancers of unknown primary, treated with radiotherapy. RESULTS: The PPVs of 12 week PET-CT in HPV positive and negative disease are 30% and 81.8% respectively (p < 0.01). The NPVs of 12 week PET-CT in HPV positive and negative disease are 92.9% and 55.6% respectively (p < 0.01). 67% of HPV positive patients with equivocal responses on 12 week PET-CT achieved complete response by 24 weeks. Equivocal responses in HPV positive disease had statistically similar survival to patients with complete responses. Comparing disease and imaging characteristics, there were no predictors of residual tumour. CONCLUSIONS: HPV positive tumours have a poor PPV of 30% on 12 week surveillance PET-CTs and take longer to achieve complete response. A period of further surveillance can be considered instead of an immediate neck dissection in this group of patients.


Asunto(s)
Neoplasia Residual/patología , Neoplasias Orofaríngeas/patología , Infecciones por Papillomavirus/patología , Adulto , Anciano , Anciano de 80 o más Años , Quimioradioterapia/métodos , Supervivencia sin Enfermedad , Femenino , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/terapia , Neoplasias de Cabeza y Cuello/virología , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Neoplasia Residual/terapia , Neoplasia Residual/virología , Neoplasias Orofaríngeas/terapia , Neoplasias Orofaríngeas/virología , Infecciones por Papillomavirus/virología , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Carcinoma de Células Escamosas de Cabeza y Cuello/virología , Tomografía Computarizada por Rayos X
7.
J Clin Oncol ; 35(26): 3030-3038, 2017 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-28437161

RESUMEN

Purpose To assess the efficacy and safety of trastuzumab plus capecitabine with or without pertuzumab in patients with human epidermal growth factor receptor 2-positive metastatic breast cancer who experienced disease progression during or after trastuzumab-based therapy and received a prior taxane. Patients and Methods Patients were randomly assigned to arm A: trastuzumab 8 mg/kg → 6 mg/kg once every 3 weeks plus capecitabine 1,250 mg/m2 twice a day (2 weeks on, 1 week off, every 3 weeks); or arm B: pertuzumab 840 mg → 420 mg once every 3 weeks plus trastuzumab at the same dose and schedule as arm A plus capecitabine 1,000 mg/m2 on the same schedule as arm A. The primary end point was independent review facility-assessed progression-free survival (IRF PFS). Secondary end points included overall survival (OS) and safety. Hierarchical testing procedures were used to control type I error for statistical testing of IRF PFS, OS, and objective response rate. Results Randomly assigned (intent-to-treat) populations were 224 and 228 patients in arms A and B, respectively. Median IRF PFS at 28.6 and 25.3 months' median follow-up was 9.0 v 11.1 months (hazard ratio, 0.82; 95% CI, 0.65 to 1.02; P = .0731) and interim OS was 28.1 v 36.1 months (hazard ratio, 0.68; 95% CI, 0.51 to 0.90). The most common adverse events (all grades; incidence of ≥ 10% in either arm and ≥ 5% difference between arms) were hand-foot syndrome, nausea, and neutropenia in arm A, and diarrhea, rash, and nasopharyngitis in arm B. Conclusion The addition of pertuzumab to trastuzumab and capecitabine did not significantly improve IRF PFS. An 8-month increase in median OS to 36.1 months with pertuzumab was observed. Statistical significance for OS cannot be claimed because of the hierarchical testing of OS after the primary PFS end point; however, the magnitude of OS difference is in keeping with prior experience of pertuzumab in metastatic breast cancer. No new safety signals were identified.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/enzimología , Receptor ErbB-2/biosíntesis , Anticuerpos Monoclonales Humanizados/administración & dosificación , Neoplasias de la Mama/patología , Capecitabina/administración & dosificación , Progresión de la Enfermedad , Esquema de Medicación , Femenino , Humanos , Metástasis de la Neoplasia , Trastuzumab/administración & dosificación
8.
N Engl J Med ; 374(15): 1444-54, 2016 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-27007578

RESUMEN

BACKGROUND: The role of image-guided surveillance as compared with planned neck dissection in the treatment of patients with squamous-cell carcinoma of the head and neck who have advanced nodal disease (stage N2 or N3) and who have received chemoradiotherapy for primary treatment is a matter of debate. METHODS: In this prospective, randomized, controlled trial, we assessed the noninferiority of positron-emission tomography-computed tomography (PET-CT)-guided surveillance (performed 12 weeks after the end of chemoradiotherapy, with neck dissection performed only if PET-CT showed an incomplete or equivocal response) to planned neck dissection in patients with stage N2 or N3 disease. The primary end point was overall survival. RESULTS: From 2007 through 2012, we recruited 564 patients (282 patients in the planned-surgery group and 282 patients in the surveillance group) from 37 centers in the United Kingdom. Among these patients, 17% had nodal stage N2a disease and 61% had stage N2b disease. A total of 84% of the patients had oropharyngeal cancer, and 75% had tumor specimens that stained positive for the p16 protein, an indicator that human papillomavirus had a role in the causation of the cancer. The median follow-up was 36 months. PET-CT-guided surveillance resulted in fewer neck dissections than did planned dissection surgery (54 vs. 221); rates of surgical complications were similar in the two groups (42% and 38%, respectively). The 2-year overall survival rate was 84.9% (95% confidence interval [CI], 80.7 to 89.1) in the surveillance group and 81.5% (95% CI, 76.9 to 86.3) in the planned-surgery group. The hazard ratio for death slightly favored PET-CT-guided surveillance and indicated noninferiority (upper boundary of the 95% CI for the hazard ratio, <1.50; P=0.004). There was no significant difference between the groups with respect to p16 expression. Quality of life was similar in the two groups. PET-CT-guided surveillance, as compared with neck dissection, resulted in savings of £1,492 (approximately $2,190 in U.S. dollars) per person over the duration of the trial. CONCLUSIONS: Survival was similar among patients who underwent PET-CT-guided surveillance and those who underwent planned neck dissection, but surveillance resulted in considerably fewer operations and it was more cost-effective. (Funded by the National Institute for Health Research Health Technology Assessment Programme and Cancer Research UK; PET-NECK Current Controlled Trials number, ISRCTN13735240.).


Asunto(s)
Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeza y Cuello/terapia , Disección del Cuello , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/cirugía , Quimioradioterapia , Femenino , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Análisis de Intención de Tratar , Estimación de Kaplan-Meier , Metástasis Linfática/diagnóstico , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Estudios Prospectivos , Calidad de Vida , Tasa de Supervivencia
9.
Radiat Oncol ; 8: 129, 2013 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-23714579

RESUMEN

BACKGROUND: The purpose of this study was to demonstrate how magnetic resonance imaging (MRI) patient position protocols influence registration quality in patients with oropharyngeal cancer undergoing radical radiotherapy and the consequences for gross tumour volume (GTV) definition and radiotherapy planning. METHODS AND MATERIALS: Twenty-two oropharyngeal patients underwent a computed tomography (CT), a diagnostic MRI (MRI(D)) and an MRI in the radiotherapy position within an immobilization mask (MRI(RT)). Clinicians delineated the GTV on the CT viewing the MRI(D) separately (GTV(C)); on the CT registered to MRI(D) (GTV(D)) and on the CT registered to MRI(RT) (GTV(RT)). Planning target volumes (PTVs) were denoted similarly. Registration quality was assessed by measuring disparity between structures in the three set-ups. Volumetric modulated arc therapy (VMAT) radiotherapy planning was performed for PTV(C), PTV(D) and PTV(RT). To determine the dose received by the reference PTV(RT), we optimized for PTV(C) and PTV(D) while calculating the dose to PTV(RT). Statistical significance was determined using the two-tailed Mann-Whitney or two-tailed paired student t-tests. RESULTS: A significant improvement in registration accuracy was found between CT and MRI(RT) versus the MRI(D) measuring distances from the centre of structures (geometric mean error of 2.2 mm versus 6.6 mm). The mean GTV(C) (44.1 cm3) was significantly larger than GTV(D) (33.7 cm3, p value = 0.027) or GTV(RT) (30.5 cm3, p value = 0.014). When optimizing the VMAT plans for PTV(C) and investigating the mean dose to PTV(RT) neither the dose to 99% (58.8%) nor 95% of the PTV (84.7%) were found to meet the required clinical dose constraints of 90% and 95% respectively. Similarly, when optimizing for PTV(D) the mean dose to PTV(RT) did not meet clinical dose constraints for 99% (14.9%) nor 95% of the PTV (66.2%). Only by optimizing for PTV(RT) were all clinical dose constraints achieved. CONCLUSIONS: When oropharyngeal patients MRI scans are performed in the radiotherapy position there are significant improvements in CT-MR image registration, target definition and PTV dose coverage.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Neoplasias Orofaríngeas/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Imagen Multimodal , Radioterapia de Intensidad Modulada , Tomografía Computarizada por Rayos X
10.
J Med Phys ; 37(1): 8-13, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22363107

RESUMEN

The aim of this study was to compare various dosimetric parameters of dynamic mlc intensity modulated radiotherapy (IMRT) plans with volumetric modulated arc therapy (VMAT) plans for sino-nasal cancers, which are rare and complex tumors to treat with radiotherapy. IMRT using five fields, coplanar in the sagittal plane and VMAT employing two coplanar arc plans were created for five patients. The plans were assessed by comparing Conformity Index and Sigma Index (dose homogeneity) in the Planning Target Volume (PTV) and through comparison of dose-volume characteristics to the following organs at risk (OARs): Spinal cord, brainstem, eye, ipsilateral and contralateral optic nerve and the volume of brain receiving 10% of the prescribed dose (V(10%)). The total monitor units required to deliver the plan were also compared. Conformity Index was found to be superior in VMAT plans for three patients and in IMRT plans for two patients. Dose homogeneity within the PTV was better with VMAT plans for all five cases. The mean difference in Sigma Index was 0.68%. There was no significant difference in dose between IMRT and VMAT plans for any of the OARs assessed in these patients. The monitor units were significantly reduced in the VMAT plan in comparison to the IMRT plan for four out of five patients, with mean reduction of 66%. It was found in this study that for the treatment of sino-nasal cancer, VMAT produced minimal, and statistically insignificant improvement in dose homogeneity within the PTV when compared with IMRT. VMAT plans were delivered using significantly fewer monitor units. We conclude in this study that VMAT does not offer significant improvement of treatment for sino-nasal cancer over the existing IMRT techniques, but the findings may change with a larger sample of patients in this rare condition.

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