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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: PURPOSE, METHODS, RESULTS. Meshes: Age of Onset, Cornea, Corneal Topography, Humans, Keratoconus, Keratoplasty, Penetrating, Prospective Studies, Risk Factors, Surveys and Questionnaires.
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Morphological variants in keratoconus: anatomical observation or aetiologically significant? Context: Two morphological cone variants are identified in keratoconus; nipple and oval. The present study was designed to assess the impact of aetiological factors on cone morphology. As part of a prospective controlled study, keratoconic subjects from a suburban practice (n = 89) underwent videokeratograph examination and completed a questionnaire detailing aetiological factors. Comparison of 95% confidence limits (CL; bootstrap method) for apical power between the two cone morphology groups showed no statistical significance. Oval cones were located at a greater eccentricity than nipple cones, as their definitions suggest. Associations between aetiological factors examined and the morphology of the cone were not significant (bootstrapped 95% CL).
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Despite the suggestion of morphological variants in keratoconus, the results of the present study suggest a common cone aetiology.