✓ Transsphenoidal microdissection has been proposed as a preferred means of treating Cushing's disease. This procedure allows the surgeon to remove a pituitary microadenoma and at the same time to preserve normal tissue. Two cases described here were treated by this method. An interesting and important observation was that neither patient appeared to be cured for 2 to 6 weeks after surgery, as assessed by dexamethasone suppression. Later, normal suppressibility occurred and the course of each patient was compatible with cure. Patients treated by this method should not be automatically retreated because of adrenocorticotropic hormone (ACTH) non-suppressibility in the early postoperative period.