Indications for contrast medium enhancement in computed tomography of the brain

The use of contrast medium enhancement in computed tomography almost doubles the duration of each examination. As the clinical demand is far greater than the scanning time available, it is desirable to use contrast medium with discrimination. The following indications are suggested for extended examinations with contrast: 1. Lesions shown by alternative neuroradiological investigations. 2. Local abnormality shown on plain scan. 3. Suspected posterior fossa lesions. 4. Suspected suprasellar lesions. In a retrospective review of 3000 patient examinations, 430 patients falling outside the above criteria had been given contrast medium. In only one patient in this latter group was an abnormality shown after contrast enhancement. In the other 429 patients, no additional information was obtained. These figures support the indications suggested for the use of contrast enhancement.