IS CORTICAL SPOKE CATARACT DUE TO LENS FIBER BREAKS - THE RELATIONSHIP BETWEEN FIBER FOLDS, FIBER BREAKS, WATERCLEFTS AND SPOKE CATARACT

Fibre folds, previously called lamellar separation of the lens, have b een found by electron microscopy to be associated with fibre breaks, w hich are seen in vivo as the circular shades of Obazawa. This led to t he present study to determine the relationship between fibre folds, fi bre breaks, waterclefts and spoke cataract. All lenses with fibre fold s were found to have circular shades. A few instances of circular shad es without fibre folds were found, suggesting that the fibre break may be the primary pathology. It was found that circular shades occurred in association with spoke cataract only when fibre folds were also pre sent. Thus there is no essential causal relationship between fibre bre aks and spoke cataract. The occurrence of waterclefts was unrelated to the presence of the other features. The lower nasal quadrant of the l ens was the most common site for the four features. The depth of spoke cataracts was found to be unrelated to the age of the patient, which makes it unlikely that accommodational stress at the time of onset of presbyopia is causative.