Normalization of visual fields following bromocriptine treatment in hyperprolactinemic patients with visual field constriction.

Two patients with galactorrhea-amenorrhea and bilateral visual field defects were studied. Routine radiologic examination of each patient revealed a normal sella turcica and no demineralization of the posterior clinoid process. Serum prolactin levels were elevated (patient V. G., 80 ng/ml; patient S. R., 204 ng/ml). Within 2 months of bromocriptine therapy, the serum prolactin levels were normal (patient V. G., 12.21 ng/ml; patient S. R., 8.25 ng/ml) and the bilateral visual field defects were corrected. Bromocriptine has been shown to control prolactin secretion in patients with prolactin-secreting pituitary tumors. Normalization of restricted visual fields following bromocriptine therapy indicates the possibility of an anatomical regression of pituitary hyperplasia or an underlying prolactin-producing microadenoma. It is speculated that the modality of functional galactorrhea reflects hyperplasia of the lactotrophs preceding a nodular and ultimately an adenomatous change. The continuous and prolonged administration of bromocriptine may prevent such a progressive sequence. Further experience is required to validate this possibility.