Relative value of computed tomography and hypocycloidal tomography in the diagnosis of pituitary microadenoma. A radio-surgical correlative study.

The relative value of a second generation CT scanner and complex motion polytomography are compared in 36 patients undergoing transsphenoidal surgery due to clinical and biological evidence of pituitary hypersecretion. CT findings of focal glandular hypodensity in 17 patients and upward convexity of the sellar contents in 15 patients suggested the presence of a pituitary microadenoma. Complex motion tomographic findings suggesting a microadenoma were found in 21 of 32 cases and included bulging of the sellar floor or localized thinning of the lamina dura. Selective transsphenoidal adenomectomy was performed on 34 of the 36 patients and the preoperative location based on CT scanning data was positively correlated with surgical results in 75% of the cases. When there is a strong clinical suspicion of pituitary hypersecretion both CT and polytomography may suggest the existence and location of a microadenoma. CT should be the radiographic technique of choice since it produces accurate information as to the size and density of the pituitary gland.