CONTRIBUTION OF THE ULTRASOUND BIOMICROSC OPY TO THE CONSERVATIVE TREATMENT OF ANTERIOR UVEAL MELANOMAS

Background Ultrasound Biomicroscopy (UBM) is a new ophthalmological im aging technique essentially designed for the study of the anterior eye segment. Over the last 10 months, we've evaluated its contribution to the conservative treatment of anterior uveal melanoma's by means of a ccelerated proton beam irradiation. Material Using UBM, we have examin ed 55 cases of uveal melanoma's, whose anterior border was situated at 6 mm or less from the limbus and that were consequently treated by pr oton beam irradiation. Results The presumed tumoral origin was the cil iary body's pars plicata in 13 cases and the pars plana or the choroid in 42 cases, 17 of which presented a tumoral invasion of the pars pli cata. A pars plana detachment anterior to or surrounding the anterior tumoral border, was present in 22 cases, The height of the tumor could only be measured by UBM if it was less than 2.5 mm. Informations gath ered using UBM have contributed to an improvement of the therapy plan in 32 cases. Conclusion Because of the strong attenuation of the high frequency ultrasound signal, UBM can only be used for the examination of intra-ocular structures situated in direct neighbourhood to the glo bal wall. Despite this technical limitation, ist contribution to the p lanning of the conservative treatment of anterior uveal melanoma's by proton beam irradiation has appeared to be considerable.