Purpose: Chiasmapexy is a poorly described surgical procedure adopted to correct the downward displacement of suprasellar visual system (SVS) into an empty sella (ES) causing visual worsening. The aim of our study is to define the indications for extradural and intradural chiasmapexy.
Methods: A systematic literature review has been performed on MEDLINE database (US National Library of Medicine), including only articles that depicted cases of surgically treated patients affected by ES and progressive delayed visual worsening. Moreover, we have reported three cases of secondary ES syndrome (SESS) with visual worsening treated in our Department with transsphenoidal (TS) microsurgical intradural approach. Finally, we have compared the results of extradural and intradural chiasmapexy described in literature.
Results: The etiology of visual impairment is different in primary and secondary ESS. In primary ESS (PESS) the only predisposing factor is a dehiscence of diaphragma sellae, and the anatomical distortion caused by displacement of optic chiasm or traction of pituitary stalk and infundibulum may determine a direct injury of neural fibers and ischemic damage of SVS. In PESS the mechanical elevation of SVS performed through extradural approach is sufficient to resolve the main pathologic mechanism. In SESS, arachnoidal adhesions play an important role in addition to downward herniation of SVS. Consequently, the surgical technique should provide elevation of SVS combined to intradural release of scar tissue and arachnoidal adhesions. In treatment of SESS, the intradural approaches result to be more effective, guaranteeing the best visual outcomes with the lowest complications rates.
Conclusions: The intradural chiasmapexy is indicated in treatment of SESS, instead the extradural approaches are suggested for surgical management of PESS.
Keywords: Chiasmapexy; Empty sella; Intradural; Pituitary surgery; Transsphenoidal; Visual worsening.