01813nas a2200289   4500008004100000245008600041210006900127260007000196300001400266490000600280520081400286100001901100700001701119700002801136700002201164700002101186700002301207700002301230700001901253700002101272700002301293700001801316700002201334700001801356700001901374856013001393       2007                        eng d00aAppearance-based Approach to Extract an Age-related Biomarker from Retinal Images0 aAppearancebased Approach to Extract an Agerelated Biomarker from  aErlangenbFriedrich-Alexander University Erlangen-Nurembergc2007  a127 - 1310 v13 a<p>We present an appearance-based method that extracts a new age-related biomarker from retina images. The Principal Component Analysis is applied on intensity values of the illumination corrected green channel of fundus images. The algorithm does not use segmentation, is robust and shows a high range of reliability. It identiﬁed an age-related feature with a strong inﬂuence of the temporal parapapillary area and the optic nerve head. The feature correlates with chronological age of the participants and is signiﬁcantly inﬂuenced by the appearance of cardiovascular risk factors such as smoking and hypertension, and thus it can be designated a biomarker. We extract and validate a medical parameter from retina images applying a purely data-driven approach without using any prior knowledge.</p>1 aBock, Rudriger1 aMeier, Jörg1 aNyúl, László, Gábor1 aWärntges, Simone1 aMichelson, Georg1 aHornegger, Joachim1 aHornegger, Joachim1 aMayr, Ernst, W1 aSchookin, Sergey1 aFeußner, Hubertus1 aNavab, Nassir1 aGulyaev, Yuri, V.1 aHöller, Kurt1 aGanzha, Victor  uhttps://home.inf.u-szeged.hu/en/publication/appearance-based-approach-to-extract-an-age-related-biomarker-from-retinal-images02494nas a2200193   4500008004100000020001400041245009500055210006900150260000900219300000900228490000700237520180400244100002102048700002202069700001902091700002802110700002302138856013902161       2007                        eng d  a0146-040400aExtraction of an Age-Related Biomarker From Retinal Images Using Appearance Based Approach0 aExtraction of an AgeRelated Biomarker From Retinal Images Using   c2007  a21670 v483 a<p>Purpose:To develop an appropriate algorithm from retina imagesusing an appearance-based version of the Principal Component Analysis and to test the age-related biomarker’s significance for patients at cardiovascular risk. Methods:Sixty-five men (age, 44.2 ± 11.4 years) and 60 women (age, 48.8 ± 12.6 years) without cardiovascular risk factors and without pathologic eye diagnosis were acquired during a clinical non-experimental cross-sectional survey and represented the control group. Forty-four hypertensive men (age, 45.5 ± 9.4 years; hypertensive for 5.9 ± 6.7 years) and 26 hypertensive women (age, 51.2 ± 7.3 years; hypertensive for 7.9 ± 7.1 years) as well as 57 male smokers (age, 41.8 ± 8.5 years; smoking for 20.6 ± 9.8 years; 15.3 ± 8.6 cigarettes per day) and 60 female smokers (age, 43.2 ± 9.5 years; smoking for 20.1 ± 10.7 years; 13.5 ± 8.1 cigarettes per day) were matched for age and sex to the respective number of control subjects. Results:The reliability of the algorithm was 0.958. The retinal biomarker correlated with age (men, -0.284, p = 0.017; women, -0.374, p = 0.001). Smokers showed a lower biomarker value (male, -0.16 ± 1.29; female, -0.12 ± 0.11) than age-matched control subjects (male, 0.72 ± 0.92, p &lt; 0.001; female, 0.24 ± 0.98, p = 0.048). Hypertension had a similar influence to the biomarker in men (0.10 ± 0.84), but not in women (-0.46 ± 1.23) as compared to age-matched controls (male, 0.57 ± 0.95, p = 0.01; female, 0.06 ± 0.99, p = 0.09). Conclusions:The algorithm of the appearance-based version of the Principal Component Analysis identified an age-related image feature dependent on light intensity with a strong influence to the temporal parapapillary area. It may be used to identify patients at cardiovascular risk.</p>1 aMichelson, Georg1 aWärntges, Simone1 aBock, Rudriger1 aNyúl, László, Gábor1 aHornegger, Joachim  uhttps://home.inf.u-szeged.hu/en/publication/extraction-of-an-age-related-biomarker-from-retinal-images-using-appearance-based-approach