Ovarian tumors are classified on the basis of tumor origin as epithelial tumors (serous and mucinous tumors, endometrioid and clear cell carcinomas, Brenner tumor), germ cell tumors (mature and immature teratomas, dysgerminoma, endodermal sinus tumor, embryonal carcinoma), sex cord-stromal tumors (fibrothecoma; granulosa cell, sclerosing stromal, and Sertoli-Leydig cell tumors), and metastatic tumors. Epithelial tumors are primarily cystic and, when malignant, are associated with varying proportions of a solid component. Papillary projections are a distinctive feature of epithelial tumors. Profuse papillary projections are highly suggestive of borderline (low-malignant-potential) or malignant tumor. Ovarian teratomas demonstrate lipid material at computed tomography and magnetic resonance (MR) imaging. Malignant germ cell tumors manifest as a large, complex abdominal mass that contains both solid and cystic components. Tumor markers are helpful in diagnosis. The radiologic appearance of sex cord-stromal tumors varies from small solid masses to large multicystic masses. Granulosa cell tumors are usually large multicystic masses with solid components. Fibrothecoma, sclerosing stromal tumor, and Sertoli-Leydig cell tumors are usually solid masses. Fibromas have very low signal intensity on T2-weighted MR images. Certain radiologic findings predominate for each type of tumor. Knowledge of these key features of ovarian tumors provides the criteria for making a specific diagnosis or substantially narrowing the differential diagnosis.

The prevalence of CAF at coronary CTA was 0.9%, which is higher than the known prevalence based on conventional angiographic findings (0.05-0.25%). Furthermore, the most common type of CAF in this study was coronary to pulmonary artery, whereas coronary artery to ventricle fistula was previously considered the most common type in studies conducted with conventional angiography. Coronary CTA is a useful, noninvasive imaging modality for the detection of CAF.

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The tracheal tumors were eccentric, well-defined, polypoid masses in all cases. The endobronchial tumors were masses confined within the bronchus in all cases, and atelectasis or pneumonia of the distal parenchyma was frequently associated. Of the six hamartomas, one was a fatty mass, and two were nodules with calcification. The others were soft-tissue-density nodules. The lipomas manifested as fat density on CT scans in both cases. The other benign tumors were low-attenuating, soft-tissue-density masses without characteristic findings on CT scans.