Craniopharyngiomas: The Importance of Early Recognition of the Pituitary Stalk

Introduction: The pituitary stalk is the essential structure that should be early identify in the suprasellar region to preserve pituitary function. The classification proposed by Kassam et al, according to the relationship between the lesion and the infundibulum, in Type I (preinfundibular), Type II (transinfundibular) and Type III (retroinfundibular) is the most useful when this lesions are approach from endoscopic endonasal. Additionally, the Type 0 has been suggested by Jamshidi et al, referring to lesions restricted to the sella. Recurrences should be considered in a different type because of the distortion of the anatomy as a result of a prior surgery.

Objectives: the aim of this study is to correlate preoperative magnetic resonance imaging (MRI) with the surgical findings of the pituitary stalk during endoscopic endonasal surgery of craniopharyngiomas.

Materials and Methods: 15 cases were included. The MRI of all the patients were correlated with the surgical findings.

Results: According to the classification, the distribution was: Type 0: 4 (27%), Type I: 2 (13%), Type II: 4 (27%), Type III: 1 (7%), Type IV: 2 (13%), Recurrences: 2 (13%). In most of the cases (13; 87%), the stalk has been recognized in the preoperative MRI. The most challenging cases were those with Type II lesions.

Conclusion: The identification of the pituitary stalk and it relationship with lesion in the preoperative MRI allows to anticipate the anatomy of the region during the surgery, and determines the strategy for tumor removal.

Keywords: craniopharyngiomas, endoscopic endonasal approach, suprasellar region