Daniel Alvarez

Summary

Publications

  1. doi request reprint Applying time, frequency and nonlinear features from nocturnal oximetry to OSA diagnosis
    Daniel Alvarez
    Biomedical Engineering Group, E T S Ingenieros de Telecomunicación, University of Valladolid, Camino del Cementerio s n, Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 2008:3872-5. 2008
  2. doi request reprint Feature selection from nocturnal oximetry using genetic algorithms to assist in obstructive sleep apnoea diagnosis
    Daniel Alvarez
    Biomedial Engineering Group, E T S I de Telecomunicacion, University of Valladolid, Paseo de Belén 15, 47011 Valladolid, Spain
    Med Eng Phys 34:1049-57. 2012
  3. ncbi request reprint Improving diagnostic ability of blood oxygen saturation from overnight pulse oximetry in obstructive sleep apnea detection by means of central tendency measure
    Daniel Alvarez
    E T S I de Telecomunicacion, University of Valladolid, and Hospital del Río Hortega, Servicio de Neumologia, Valladolid, Spain
    Artif Intell Med 41:13-24. 2007
  4. ncbi request reprint Cross approximate entropy analysis of nocturnal oximetry signals in the diagnosis of the obstructive sleep apnea syndrome
    Daniel Alvarez
    E T S Ingenieros de Telecommun, Valladolid Univ, Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 1:6149-52. 2006
  5. doi request reprint Assessment of four statistical pattern recognition techniques to assist in obstructive sleep apnoea diagnosis from nocturnal oximetry
    J Victor Marcos
    Biomedical Engineering Group, E T S Ingenieros de Telecomunicación, Universidad de Valladolid, Camino del Cementerio s n, 47011 Valladolid, Spain
    Med Eng Phys 31:971-8. 2009
  6. doi request reprint Single layer network classifiers to assist in the detection of obstructive sleep apnea syndrome from oximetry data
    J Victor Marcos
    Biomedical Engineering Group, E T S I de Telecomunicacion, University of Valladolid, Camino del Cementerio s n, 47011, Spain
    Conf Proc IEEE Eng Med Biol Soc 2008:1651-4. 2008
  7. ncbi request reprint Radial basis function classifiers to help in the diagnosis of the obstructive sleep apnoea syndrome from nocturnal oximetry
    J Victor Marcos
    Biomedical Engineering Group, E T S I de Telecomunicacion, University of Valladolid, Camino del cementerio, S N, 47011 Valladolid, Spain
    Med Biol Eng Comput 46:323-32. 2008
  8. doi request reprint A classification algorithm based on spectral features from nocturnal oximetry and support vector machines to assist in the diagnosis of obstructive sleep apnea
    J Victor Marcos
    The Biomedical Engineering Group, E T S I de Telecomunicacion, University of Valladolid, Camino del Cementerio s n, Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 2009:5547-50. 2009
  9. doi request reprint Utility of multilayer perceptron neural network classifiers in the diagnosis of the obstructive sleep apnoea syndrome from nocturnal oximetry
    J Victor Marcos
    Biomedical Engineering Group, E T S Ingenieros de Telecomunicación, University of Valladolid, Spain
    Comput Methods Programs Biomed 92:79-89. 2008
  10. ncbi request reprint Applying neural network classifiers in the diagnosis of the obstructive sleep apnea syndrome from nocturnal pulse oximetric recordings
    J Victor Marcos
    Biomedical Engineering Group, E T S I de Telecomunicacion, University of Valladolid, Camino del Cementerio s n, 47011 Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 2007:5174-7. 2007

Collaborators

Detail Information

Publications25

  1. doi request reprint Applying time, frequency and nonlinear features from nocturnal oximetry to OSA diagnosis
    Daniel Alvarez
    Biomedical Engineering Group, E T S Ingenieros de Telecomunicación, University of Valladolid, Camino del Cementerio s n, Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 2008:3872-5. 2008
    ..Our study showed that common statistics in the time and frequency domains and nonlinear features could provide additional and complementary information to help in OSA diagnosis...
  2. doi request reprint Feature selection from nocturnal oximetry using genetic algorithms to assist in obstructive sleep apnoea diagnosis
    Daniel Alvarez
    Biomedial Engineering Group, E T S I de Telecomunicacion, University of Valladolid, Paseo de Belén 15, 47011 Valladolid, Spain
    Med Eng Phys 34:1049-57. 2012
    ..We concluded that GAs could be an effective and robust tool to search for essential oximetric features that could enhance NPO in the context of OSA diagnosis...
  3. ncbi request reprint Improving diagnostic ability of blood oxygen saturation from overnight pulse oximetry in obstructive sleep apnea detection by means of central tendency measure
    Daniel Alvarez
    E T S I de Telecomunicacion, University of Valladolid, and Hospital del Río Hortega, Servicio de Neumologia, Valladolid, Spain
    Artif Intell Med 41:13-24. 2007
    ..Specifically, we assessed the validity of central tendency measure (CTM) as a screening test for OSA in patients clinically suspected of suffering from this disease...
  4. ncbi request reprint Cross approximate entropy analysis of nocturnal oximetry signals in the diagnosis of the obstructive sleep apnea syndrome
    Daniel Alvarez
    E T S Ingenieros de Telecommun, Valladolid Univ, Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 1:6149-52. 2006
    ..7, where we achieved 95.5% sensitivity, 73.3% specificity and 86.5% accuracy. Further analyses should be carried out with new and larger data sets to test the usefulness of our methodology prospectively...
  5. doi request reprint Assessment of four statistical pattern recognition techniques to assist in obstructive sleep apnoea diagnosis from nocturnal oximetry
    J Victor Marcos
    Biomedical Engineering Group, E T S Ingenieros de Telecomunicación, Universidad de Valladolid, Camino del Cementerio s n, 47011 Valladolid, Spain
    Med Eng Phys 31:971-8. 2009
    ..61% (91.05% sensitivity and 82.61% specificity) and an area under the ROC curve (AROC) of 0.925. The proposed statistical pattern recognition techniques could be applied as an OSA screening tool...
  6. doi request reprint Single layer network classifiers to assist in the detection of obstructive sleep apnea syndrome from oximetry data
    J Victor Marcos
    Biomedical Engineering Group, E T S I de Telecomunicacion, University of Valladolid, Camino del Cementerio s n, 47011, Spain
    Conf Proc IEEE Eng Med Biol Soc 2008:1651-4. 2008
    ..8%). Applying spectral and non-linear features from SaO(2) data simultaneously could be useful in OSAS diagnosis...
  7. ncbi request reprint Radial basis function classifiers to help in the diagnosis of the obstructive sleep apnoea syndrome from nocturnal oximetry
    J Victor Marcos
    Biomedical Engineering Group, E T S I de Telecomunicacion, University of Valladolid, Camino del cementerio, S N, 47011 Valladolid, Spain
    Med Biol Eng Comput 46:323-32. 2008
    ..90. Our results showed that a useful non-invasive method could be applied to diagnose OSAS from nonlinear features of SaO(2) with RBF classifiers...
  8. doi request reprint A classification algorithm based on spectral features from nocturnal oximetry and support vector machines to assist in the diagnosis of obstructive sleep apnea
    J Victor Marcos
    The Biomedical Engineering Group, E T S I de Telecomunicacion, University of Valladolid, Camino del Cementerio s n, Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 2009:5547-50. 2009
    ..4) provided an accuracy of 88.00% (84.44% sensitivity and 93.33% specificity) and an AROC of 0.921. Our results suggest that the proposed algorithm could be useful for OSAS screening...
  9. doi request reprint Utility of multilayer perceptron neural network classifiers in the diagnosis of the obstructive sleep apnoea syndrome from nocturnal oximetry
    J Victor Marcos
    Biomedical Engineering Group, E T S Ingenieros de Telecomunicación, University of Valladolid, Spain
    Comput Methods Programs Biomed 92:79-89. 2008
    ..5% (89.8% sensitivity and 79.4% specificity). Our neural network algorithm could represent a useful technique for OSAS detection. It could contribute to reduce the demand for polysomnographic studies in OSAS screening...
  10. ncbi request reprint Applying neural network classifiers in the diagnosis of the obstructive sleep apnea syndrome from nocturnal pulse oximetric recordings
    J Victor Marcos
    Biomedical Engineering Group, E T S I de Telecomunicacion, University of Valladolid, Camino del Cementerio s n, 47011 Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 2007:5174-7. 2007
    ..The RBF classifier provided the best diagnostic performance with an accuracy of 86.3% (89.9% sensitivity and 81.1% specificity)...
  11. ncbi request reprint Obstructive sleep apnea detection using clustering classification of nonlinear features from nocturnal oximetry
    Daniel Alvarez
    Biomedical Engineering Group, ETS Ingenieros de Telecomunicación, University of Valladolid, Camino del Cementerio s n, 47011, Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 2007:1937-40. 2007
    ..Our results suggest that nonlinear analysis and clustering classification could provide useful information to help in the diagnosis of OSA syndrome...
  12. doi request reprint Analysis of nocturnal oxygen saturation recordings using kernel entropy to assist in sleep apnea-hypopnea diagnosis
    J Victor Marcos
    Biomedical Engineering Group, ETSI de Telecomunicación, University of Valladolid, 47011 Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 2011:1745-8. 2011
    ..This non-linear measure can provide useful information for the development of alternative diagnostic techniques in order to reduce the demand for conventional polysomnography (PSG)...
  13. doi request reprint Spectral analysis of electroencephalogram and oximetric signals in obstructive sleep apnea diagnosis
    Daniel Alvarez
    Biomedical Engineering Group, E T S Ingenieros de Telecomunicación, University of Valladolid, Camino del Cementerio s n, 47011, Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 2009:400-3. 2009
    ..Additionally, nocturnal SaO(2) and EEG recordings during the whole night could provide complementary information to help in the detection of OSA syndrome...
  14. ncbi request reprint Utility of approximate entropy from overnight pulse oximetry data in the diagnosis of the obstructive sleep apnea syndrome
    Roberto Hornero
    Ingenieros de Telecomunicación, University of Valladolid, Spain, Camino del Cementerio s n 47011 Valladolid, Spain
    IEEE Trans Biomed Eng 54:107-13. 2007
    ..This method was assessed prospectively using the test dataset, where we obtained 82.09% sensitivity and 86.96% specificity. We conclude that ApEn analysis of SaO2 from pulse oximetric recording could be useful in the study of OSA...
  15. doi request reprint Automated prediction of the apnea-hypopnea index from nocturnal oximetry recordings
    J Victor Marcos
    Biomedical Engineering Group, E T S I Telecomunicación, University of Valladolid, Valladolid 47011, Spain
    IEEE Trans Biomed Eng 59:141-9. 2012
    ..91. The proposed MLP-based method could be used as an accurate and cost-effective procedure for SAHS diagnosis in the absence of PSG...
  16. doi request reprint Automated detection of obstructive sleep apnoea syndrome from oxygen saturation recordings using linear discriminant analysis
    J Victor Marcos
    ETSI de Telecomunicación, University of Valladolid, Valladolid, Spain
    Med Biol Eng Comput 48:895-902. 2010
    ..The proposed method could be a useful tool to assist in early OSAS diagnosis, contributing to overcome the difficulties of conventional PSG...
  17. doi request reprint Multivariate analysis of blood oxygen saturation recordings in obstructive sleep apnea diagnosis
    Daniel Alvarez
    ETSI Telecomunicacion, University of Valladolid, Valladolid, Spain
    IEEE Trans Biomed Eng 57:2816-24. 2010
    ..We conclude that simultaneous analysis in the time and frequency domains by means of statistical moments, spectral and nonlinear features could provide complementary information from NPO to improve OSA diagnosis...
  18. doi request reprint Spectral analysis of single-channel airflow and oxygen saturation recordings in obstructive sleep apnea detection
    Daniel Alvarez
    Biomedical Engineering Group, E T S Ingenieros de Telecomunicación, University of Valladolid, Paseo de Belén 15, 47011, Spain
    Conf Proc IEEE Eng Med Biol Soc 2010:847-50. 2010
    ..5%, respectively, were reached with the peak amplitude of the airflow PSD. Thus, spectral features from the very low frequency components of single-channel airflow recordings could provide useful information to help in OSA diagnosis...
  19. doi request reprint Apnea-hypopnea index estimation from spectral analysis of airflow recordings
    Gonzalo C Gutierrez-Tobal
    Biomed Engineering Group, University of Valladolid, Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 2012:3444-7. 2012
    ..The accuracy achieved was higher as the threshold increased (69.7%, 75.3%, 80.9%, 87.6%) These results suggest that the automated estimation of AHI through spectral features can provide useful knowledge about SAHS severity...
  20. ncbi request reprint Oxygen saturation regularity analysis in the diagnosis of obstructive sleep apnea
    Felix del Campo
    Hospital del Rio Hortega, Servicio de Neumologia, C Cardenal Torquemada s n, 47010 Valladolid, Spain
    Artif Intell Med 37:111-8. 2006
    ....
  21. doi request reprint Assessment of feature selection and classification approaches to enhance information from overnight oximetry in the context of apnea diagnosis
    Daniel Alvarez
    Biomedical Engineering Group GIB, University of Valladolid, Paseo Belén 15, 47011, Valladolid, Spain
    Int J Neural Syst 23:1350020. 2013
    ..Our results suggest that reduced subsets of complementary features (25% to 50% of total features) and classifiers with high generalization ability could provide high-performance screening tools in the context of SAHS. ..
  22. doi request reprint Feature selection using a genetic algorithm in a motor imagery-based Brain Computer Interface
    Rebeca Corralejo
    Biomedical Engineering Group, GIB, Dpto TSCIT, University of Valladolid, Paseo Belén 15, 47011 Valladolid, Spain
    Conf Proc IEEE Eng Med Biol Soc 2011:7703-6. 2011
    ..336) and the winner competition results (kappa coefficient of 0.600). These preliminary results demonstrated that the proposed methodology could be useful to control motor imagery-based BCI applications...
  23. doi request reprint Assessment of four neural network based classifiers to automatically detect red lesions in retinal images
    Maria Garcia
    Grupo de Ingeniería Biomédica, E T S Ingenieros de Telecomunicación, University of Valladolid, Paseo Belén 15, 47011 Valladolid, Spain
    Med Eng Phys 32:1085-93. 2010
    ..01% and a mean positive predictive value of 51.99% were obtained. With an image-based criterion, a mean sensitivity of 100%, mean specificity of 56.00% and mean accuracy of 83.08% were achieved...
  24. ncbi request reprint Interpretation of the Lempel-Ziv complexity measure in the context of biomedical signal analysis
    Mateo Aboy
    Electronics Engineering Technology Department, Oregon Institute of Technology, Portland, OR 97006, USA
    IEEE Trans Biomed Eng 53:2282-8. 2006
    ..Our results indicate that LZ is particularly useful as a scalar metric to estimate the bandwidth of random processes and the harmonic variability in quasi-periodic signals...
  25. ncbi request reprint Renal function and outcome of PTRA and stenting for atherosclerotic renal artery stenosis
    Felipe Ramos
    Instituto de Cardiologia y Cirugia Cardiovascular ICYCC, Fundacion Favaloro, Buenos Aires, Argentina
    Kidney Int 63:276-82. 2003
    ..The factors predicting benefit remain controversial. We tested the hypothesis that the baseline glomerular filtration rate (GFR) predicts the changes in GFR and blood pressure (BP) after PTRAS...