This prospective study sought to verify whether computed tomography (CT) and magnetic resonance imaging (MRI) can be used as reliable means for planning a therapeutic approach to lacrimal fossa tumors. Twenty-six cases of lacrimal of a gland mass at first observation were studied. After clinical and radiologic evaluation, the most likely diagnosis was recorded for each patient before treatment. The conclusive diagnosis was based on a histologic examination or (only in case of acute pseudotumor) on a prompt and complete response to steroids. All lymphomas (seven cases) and pseudotumors (four cases) were correctly identified. Two cases of benign lymphoid hyperplasia were suspected to be pseudotumors. All epithelial tumors (six cases) were recognized, except for a pseudocystic necrotic carcinoma, which was suspected to be a dermoid. All dermoids (five cases) were identified. An intraosseous hemangioma was suspected to be an aneurysmal bone cyst, and a cholesterol granuloma was suspected to be a dermoid. CT and MRI, combined with clinical recognition of inflammatory signs, can provide sufficient information to guide the therapeutic approach to lacrimal fossa tumors. Identification of rare tumors and the differentiation of carcinomas from adenomas may result. General guidelines for treatment include: Excisional biopsy for rounded tumors with smooth margins (including cystic lesions) A steroid trial for recent wedge-shaped tumors Incisional biopsy for longstanding or steroid-resistant wedge-shaped tumors.