[Treatment of Rathke's Cleft Cyst:Technical Note for Preservation of Pituitary Function].

: Pituitary dysfunction, such as panhypopituitarism or diabetes insipidus(DI), is often found in patients with Rathke's cleft cyst. Patients were treated with transsphenoidal microscopic surgery; however, pituitary dysfunction did not usually recover. Recently, endoscopic transsphenoidal surgery(eTSS)has enabled minimally invasive surgery for patients with Rathke's cleft cyst. In this study, we analyzed 22 consecutive patients with Rathke's cleft cyst who underwent eTSS to determine if pituitary dysfunction recovered. The follow-up period ranged from 3 months to 19.25 years(mean, 4.75 years). Preoperative endocrinological evaluation showed impaired secretion of adrenocorticotropic hormone(ACTH)in 4 cases(18.2%), thyroid-stimulating hormone(TSH)in 2 cases(9.1%), hyperprolactinemia in 5 cases(22.7%), growth hormone(GH)in 9 cases(40.9%), and luteinizing hormone(LH)/follicle-stimulating hormone(FSH)in 11 cases(50%). In addition, preoperative DI was found in 2 cases(9.1%). We planned the site of fenestration for the cyst wall using preoperative sagittal magnetic resonance imaging. As a result, the recovery rate for ACTH, GH, and TSH secretion was 25%, 33.3%, and 50%, respectively. On the other hand, two patients with DI and other hormonal deficiencies did not recover pituitary function because of severe inflammation. Pituitary function might be preserved with minimally invasive surgery for Rathke's cleft cyst with mild inflammation.