@article {1085,
	title = {Extraction of an Age-Related Biomarker From Retinal Images Using Appearance Based Approach},
	journal = {INVESTIGATIVE OPHTHALMOLOGY \& VISUAL SCIENCE},
	volume = {48},
	year = {2007},
	note = {ARVO Meeting Abstracts},
	month = {2007},
	pages = {2167},
	type = {Journal article},
	abstract = {<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{\textquoteright}s significance for patients at cardiovascular risk. Methods:Sixty-five men (age, 44.2 {\textpm} 11.4 years) and 60 women (age, 48.8 {\textpm} 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 {\textpm} 9.4 years; hypertensive for 5.9 {\textpm} 6.7 years) and 26 hypertensive women (age, 51.2 {\textpm} 7.3 years; hypertensive for 7.9 {\textpm} 7.1 years) as well as 57 male smokers (age, 41.8 {\textpm} 8.5 years; smoking for 20.6 {\textpm} 9.8 years; 15.3 {\textpm} 8.6 cigarettes per day) and 60 female smokers (age, 43.2 {\textpm} 9.5 years; smoking for 20.1 {\textpm} 10.7 years; 13.5 {\textpm} 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 {\textpm} 1.29; female, -0.12 {\textpm} 0.11) than age-matched control subjects (male, 0.72 {\textpm} 0.92, p \&lt; 0.001; female, 0.24 {\textpm} 0.98, p = 0.048). Hypertension had a similar influence to the biomarker in men (0.10 {\textpm} 0.84), but not in women (-0.46 {\textpm} 1.23) as compared to age-matched controls (male, 0.57 {\textpm} 0.95, p = 0.01; female, 0.06 {\textpm} 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>},
	isbn = {0146-0404},
	author = {Georg Michelson and Simone W{\"a}rntges and Rudriger Bock and L{\'a}szl{\'o} G{\'a}bor Ny{\'u}l and Joachim Hornegger}
}
