Comparison of serum prolactin, plain radiography, and hypocycloidal tomography of the sella turcica in patients with galactorrhea.

Hypocycloidal tomography of the sella turcica is being used with increasing frequency in patients with galactorrhea in order to establish the diagnosis of pituitary adenoma. In 201 patients with galactorrhea, serum prolactin (PRL) levels were correlated with anteroposterior (AP)--lateral plain radiographs and hypocycloidal tomography of the sella turcica. Plain films were normal in 167 and abnormal in 34 patients. Of the 167 patients with normal AP-lateral plain films, 80 had normal tomograms and normal serum prolactin levels while 80 patients had normal tomograms and elevated serum PRL levels (21 to 256 ng/ml). The remaining seven of the 167 patients had normal plain films with abnormal tomograms and elevated serum PRL levels (28 to 176 ng/ml). All patients with abnormal plain radiographs had abnormal tomograms and had either elevated or normal serum PRL levels. In view of these findings, sella tomography is only necessary in patients with normal plain radiographs and elevated serum PRL levels.