An incidentally detected lesion or anatomical abnormalities that by themselves are not responsible for clinical symptoms or signs at the time of detection are termed as incidentalomas. The classification here is based on the fact that few pituitary lesions are only radiological artifacts and rest involves in the increase in pituitary volume. These radiological artifacts are common but small in size. Pituitary hypertrophy because of adolescence, pregnancy, estrogen replacement, and hypothyroidism are common. Nonpituitary anatomical anomalies are: primary empty sella syndrome, sellar spine, and intrasellar trigeminal artery. Pituitary microadenoma and pituitary macroadenoma are the true pathological alterations. The latter part of this chapter gives information about Rathke’s cleft cysts, metastases, tuberculosis, and postoperative pseudotumor.