title: Ring formation on computerized tomography in the postoperative patient.
abstract: Ring formation with contrast infusion in computerized tomography has been described with various entities. The current report demonstrates its appearance in three postoperative patients from whom cerebral tumors had been removed. These examples of postoperative ring formation are compared with the ring formation in the scan of an unoperated patient with an intracerebral hematoma.
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging / Q000601:surgery*; D001932:Brain Neoplasms / Q000601:surgery; D002277:Carcinoma / Q000601:surgery; D002543:Cerebral Hemorrhage / Q000601:surgery; D005260:Female; D006406:Hematoma / Q000601:surgery; D006801:Humans; D008297:Male; D008577:Meningeal Neoplasms / Q000601:surgery; D008579:Meningioma / Q000601:surgery; D008875:Middle Aged; D009362:Neoplasm Metastasis; D011182:Postoperative Care; D014057:Tomography, X-Ray Computed