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Aims/Purpose: To determine the association between dry eye with higher order aberrations (HOAs) and contrast sensitivity in 60 years old people and over. Methods: This population‐based study was conducted in Tehran, the capital of Iran, using stratified multistage random cluster sampling. All participants underwent complete ocular examination including measurement of uncorrected and best‐corrected visual acuity, refraction, slit‐lamp biomicroscopy. Zywave was used for measuring HOAs aberrations. Contrast sensitivity was measured with best correction visual acuity using the CVS1000 grating charts. Schirmer and tear break‐up time (TBUT) tests were used for evaluating dry eye in participants. Results: After applying exclusion criteria, the data of 397 individuals were analysed. A total of 415 people were invited, of whom 397 (62.8%) were females. The mean age of the participants was 68.32 ± 5.49 years. After adjusting with age and sex, in the multiple regression model that the TBUT test has a direct association with spherical aberration (p = 0.017) and an inverse association with coma, trefoil and the third, fourth and fifth order aberrations (p < 0.05). Schirmer test results also had a positive relationship with spherical aberration (p = 0.046) and an inverse relationship with coma, trefoil and the third, fourth and fifth order aberrations (p < 0.05). Contrast sensitivity had a significant association with Schirmer test result only in spatial frequency of 3CPD. Conclusions: The results of this study indicated the association between dry eyes and HOAs, and that the TBUT and Schirmer test results are of the most important factors in this relationship. Treating dry eye, can improve HOAs and quality of vision in elderly people. [ABSTRACT FROM AUTHOR]

Background/purpose Dermoscopy is one of the major imaging modalities used in the diagnosis of pigmented skin lesions. Due to the difficulty and subjectivity of human interpretation, computerized image analysis techniques have become important tools in this research area. Hair removal from skin lesion images is one of the key problems for the precise segmentation and analysis of the skin lesions. In this study, we present a new scheme that automatically detects and removes hairs from dermoscopy images. Methods The proposed algorithm includes two steps: firstly, light and dark hairs and ruler marking are segmented through adaptive canny edge detector and refinement by morphological operators. Secondly, the hairs are repaired based on multi-resolution coherence transport inpainting. Results The algorithm was applied to 50 dermoscopy images. To estimate the accuracy of the proposed hair detection algorithm, quantitative analysis was performed using TDR, FPR, and DA metrics. Moreover, to evaluate the performance of the proposed hair repaired algorithm, three statistical metrics namely entropy, standard deviation, and co-occurrence matrix were used. Conclusion The results demonstrate that the proposed algorithm is highly accurate and able to detect and repair the hair pixels with few errors. In addition, the segmentation veracity of the skin lesion is effectively improved after our proposed hair removal algorithm. [ABSTRACT FROM AUTHOR]

Steady-state accommodative responses to a wide range of commonly encountered textural and graphic stimuli were investigated in 12 young, visually normal subjects. Details of two experiments are described. In the first experiment, stimuli were varied in terms of size, contrast, spatial frequency, colour and intellectual demand. In the second experiment, only the colour of the targets was systematically altered. In both experiments the stimulus demand was maintained at 3 D, and accommodation was measured subjectively using a Hartinger coincidence optometer. No significant difference in mean accommodative response was observed between the widely differing targets adopted in either experiment. These findings suggest that an overall threshold exists for accommodative stimuli, with supra-threshold targets of low to moderate contrast being capable of initiating and sustaining an appropriate accommodative response. [ABSTRACT FROM AUTHOR]