Chiasmapexy for secondary empty sella syndrome: diagnostic and therapeutic considerations

Abstract
Purpose Secondary empty sella syndrome (SESS) following pituitary surgery remains a diagnostic and therapeutic challenge. The aim of this study was to specify the diagnostic criteria, surgical indications and results of chiasmapexy in the SESS. Methods Three cases from two experienced neurosurgical centers were collected and the available literature was reviewed. Results The 3 patients were operated for a giant non-functioning pituitary adenoma, a cystic macroprolactinoma, and an arachnoid cyst respectively. Postoperative visual outcome was initially improved, and then worsened progressively. At the time of SESS diagnosis, visual field defect was severe in all cases with optic nerve (ON) atrophy in 2 cases. Patients were operated via an endoscopic endonasal extradural approach. One patient was re-operated because of early fat reabsorption. Visual outcome improved in 1 case and stabilized in 2 cases. Statistical analyses performed on 24 cases from the literature review highlighted that patient age and severity of the preoperative visual defect were respectively significant and nearly significant prognostic factors for visual outcome, unlike the surgical technique. Conclusion T2-weighted or CISS/FIESTA sequence MRI is mandatory to visualize adhesions, ON kinking and neurovascular conflict. TS approach is the most commonly used approach. The literature review could not conclude on the need for an intra or extradural approach suggesting case by case adapted strategy. Intrasellar packing with non-absorbable material such as bone should be considered. Severity of the visual loss clearly decreases the visual outcome suggesting early chiasmapexy. In case of severe and long standing symptoms before surgery, benefits and surgical risks should be carefully balanced.