[Radiological parameters indicating normalization of bone lesions in Langerhans-cell histiocytosis].

The signs predicting radiological healing were studied in 35 bone lesions of 12 children with Langerhans' cell histiocytosis. The earliest and more frequent radiological signs predicting healing were a decrease in size (52%), the change from a non-sclerotic lesion to one with sclerosis (41%) and the loss of distinct margins of the lesions (29%) three months after diagnosis. The first of these signs was statistically significant after three months of follow-up, the last two after 12 months. The trabecular pattern was a late (one case after 2 years) and infrequent (observed in only 24% of lesions) sign of radiological healing.