[Cockayne's syndrome; a radiological entity: a report on two familial cases (author's transl)].

Two cases of cockayne's syndrome occurring in the same family group are reported. The authors describe the chronological evolution of the bone lesions, based on radiological examinations of the older sister made at 4, 13 1/2, and 15 years of age. Evidence that clinical signs of early ageing are associated with a rapid drop in thymic hormone levels led the authors to search for radiological signs of premature ageing. At 15 years of age only minimal signs were apparent.