BACKGROUND: Recording of the dark trough/light peak of the electrooculogram (EOG) remains a useful electrodiagnostic tool. Manual analysis of the recording is tedious and lengthy, and automated analysis needs to deal with artefacts due to suboptimal patient cooperation. METHODS: We present a novel method of automating the processing and analysis of raw EOG data using the open-source statistical software R. Rather than attempting saccade detection, we utilize the fact that basic properties of the response (rough waveform timing) are known and simply fit a square wave to each response run-free parameters are amplitude and phase. To assess this analysis method, responses from 54 eyes of 27 patients with a variety of ophthalmic diagnoses were analysed with manual calculation and with a number of automated methods of fitting the response curve. The Arden ratio was the main outcome measure. RESULTS: Robust regression of a fundamental with a three-harmonic approximation of a square wave was found to be the best method. Classification accuracy with this method compared with the manual calculations as gold standard; using a lower normal threshold of 200%, Arden ratio was found to achieve a sensitivity of 96% and specificity of 81%. Time taken to process and analyse the data for a subject was reduced from 20 min for the manual method to 2 min for the automated method. CONCLUSIONS: The simple approach yielded a surprisingly effective automatic estimation of the Arden ratio. In one author's laboratory (MB), this procedure has proved to be useful over 5 years for routine analysis.
BACKGROUND: Recording of the dark trough/light peak of the electrooculogram (EOG) remains a useful electrodiagnostic tool. Manual analysis of the recording is tedious and lengthy, and automated analysis needs to deal with artefacts due to suboptimal patient cooperation. METHODS: We present a novel method of automating the processing and analysis of raw EOG data using the open-source statistical software R. Rather than attempting saccade detection, we utilize the fact that basic properties of the response (rough waveform timing) are known and simply fit a square wave to each response run-free parameters are amplitude and phase. To assess this analysis method, responses from 54 eyes of 27 patients with a variety of ophthalmic diagnoses were analysed with manual calculation and with a number of automated methods of fitting the response curve. The Arden ratio was the main outcome measure. RESULTS: Robust regression of a fundamental with a three-harmonic approximation of a square wave was found to be the best method. Classification accuracy with this method compared with the manual calculations as gold standard; using a lower normal threshold of 200%, Arden ratio was found to achieve a sensitivity of 96% and specificity of 81%. Time taken to process and analyse the data for a subject was reduced from 20 min for the manual method to 2 min for the automated method. CONCLUSIONS: The simple approach yielded a surprisingly effective automatic estimation of the Arden ratio. In one author's laboratory (MB), this procedure has proved to be useful over 5 years for routine analysis.
Authors: Michael F Marmor; Mitchell G Brigell; Daphne L McCulloch; Carol A Westall; Michael Bach Journal: Doc Ophthalmol Date: 2011-02-05 Impact factor: 2.379
Authors: Ian M MacDonald; H V Gudiseva; Adda Villanueva; Mark Greve; Rafael Caruso; Radha Ayyagari Journal: Ophthalmic Genet Date: 2011-08-02 Impact factor: 1.803
Authors: F Krämer; K White; D Pauleikhoff; A Gehrig; L Passmore; A Rivera; G Rudolph; U Kellner; M Andrassi; B Lorenz; K Rohrschneider; A Blankenagel; B Jurklies; H Schilling; F Schütt; F G Holz; B H Weber Journal: Eur J Hum Genet Date: 2000-04 Impact factor: 4.246
Authors: Marina Mesquida; Bernardo Sanchez-Dalmau; Santiago Ortiz-Perez; Laura Pelegrín; Juan José Molina-Fernandez; Marc Figueras-Roca; Ricardo Casaroli-Marano; Alfredo Adán Journal: Case Rep Oncol Date: 2010-11-22