Ophthalmologically, CDI not only provides the morphogical diagnosis of a mass lesion and its blood supply, but also quantitates the hemodynamics. CDI (Hewlett Packard, Model sonos 1000) with a 5.5 MHz probe was applied to four orbital tumors, two orbital cystic lesions, and one intraocular tumor. The feeding arteries (FAs) and central retinal arteries (CRAs) were identified on CDI. Pulsatility and resistivity values were then calculated. Under guidance of CDIs, orbital computerized tomographs, and/or magnetic resonance imaging (MRI), all patients underwent surgical extirpation and specimens were submitted for pathological studies. Two intraconal tumors were shown to be primary cavernous hemangiomas. One extraconal tumor was shown to be a metastatic tumor from poorly differentiated gastric adenocarcinoma. The other extraconal mass was shown to be lymphoid hyperplasia (pseudotumor) from the lacrimal gland. One cystic lesion was shown to be a dermoid cyst. The intraocular tumor was shown to be a melanoma. Hemodynamic studies demonstrated that the feeding arteries of the melanoma and pseudotumor were high flow, while those of the cavernous hemangioma and nonkeratinizing orbital were medium flow, and those of the metastatic tumor and mucocele had the lowest blood flow velocities. Ophthalmologically and pathologically, this study is the first attempt to try to quantitate the hemodynamics of intraconal, extraconal and intraocular mass lesions. The specificity and sensitivity of CDI were significant but still need refining.