Endonasal Endoscopic Fenestration of Rathke's Cleft Cysts: Whether to Leave the Fenestration Open or Closed?

Rathke's cleft cysts (RCC) are generally treated with transsphenoidal fenestration and cyst drainage. If no cerebrospinal fluid (CSF) leak is created, the fenestration can be left open. If CSF is encountered, a watertight closure must be created to prevent postoperative CSF leak, though sellar closure has theoretically been linked with higher recurrence rate. In this study, we investigate the relationship between sellar closure, rate of postoperative CSF leak, and RCC recurrence.  Retrospective review of a prospective database of all endoscopic endonasal RCC fenestrations and cases were divided based on closure. The "open" group included patients who underwent fenestration of the RCC, whereas the "closed" group included patients whose RCC was treated with fat and a rigid buttress ± a nasoseptal flap. The rate of intra- and postoperative CSF leak and radiographic recurrence was determined.  The closed group had a higher rate of suprasellar extension (odds ratio [OR]: 8.0,  = 0.032) and intraoperative CSF leak ( ≤ 0.001). There were 54.8% intraoperative CSF leaks and no postoperative CSF leaks. Radiologic recurrence rate for the closed group (35.0%) was three times higher than the open group (9.1%; risk ratio [RR] = 3.85,  = 0.203), but not powered to show significance. None of the radiologic recurrences required reoperation.  Maintaining a patent fenestration between an RCC and the sphenoid sinus is important in reducing the rate of radiographic recurrence. Closure of the fenestration may be required to prevent CSF leak. While closure increases the rate of radiographic recurrence, reoperation for recurrent RCC is still an uncommon event.