[Differential intraocular tumor diagnosis in MRI using gadolinium DTPA: value in comparison with other ophthalmologic examination procedures].

To improve the tissue characterizing information obtained by MRI we examined 35 patients with 43 different intraocular lesions by applying Gadolinium-DTPA for the first time. Histology was available in seven cases. Twenty patients were diagnosed as having a malignant uveal melanoma, 2 had a melanoma of the ciliary body and the iris, 3 patients were found to have a naevus of the uvea and 3 patients suffered metastatic uveal infiltrates, 4 patients had a senile maculopathy and 10 patients had either a vitreal or a subretinal haemorrhage, 1 patient had an angioma and another a lymphoma of his vitreous. Ruthenium plaques were applied to 13 out of 20 melanoma patients. These patients were followed-up by MRI examinations at regular intervals after therapy. The pretherapeutic signals of melanotic melanomas were high before applying Gadolinium-DTPA and demonstrated a further increase after contrast enhancement. Following ruthenium therapy the drop of the precontrast signal was more pronounced than the postcontrast signal. In complicated clinical situations MRI offers additional information to enable the differentiation between intraocular tumors and haemorrhages.