Locating of the pituitary stalk for craniopharyngioma surgery of transfrontobasal interhemispheric approach.

The aim of this study was to provide a relatively safe operation range for the protection of the pituitary stalk in transfrontobasal interhemispheric approach for craniopharyngioma surgery by measuring the related parameters of the pituitary stalk. Based on the whole-head magnetic resonance imaging scans of 119 healthy subjects (57 men and 62 women) anonymously, three-dimensional reconstructions were rebuilt. The results of the study are as follows: M is the common midpoint of anterior and inferior border of anterior commissure. O and P are the midpoint of the anterior border of the pituitary stalk's superior and inferior extremity, respectively. The distance between M and O (D1) was 12.42 (SD, 2.35) mm. The distance between M and P (D2) was 22.47 (SD, 2.57) mm. The length of the pituitary stalk (D3) was 10.68 (SD, 2.34) mm. The widest diameter of the pituitary stalk (D4) was 2.78 (SD, 0.50) mm. The inclination of the pituitary stalk at the coronal plane (A1) was 2.73 (SD, 2.60) degrees. Of the 119 pituitary stalks involved in this study, 14.29% were centered, 47.06% inclined to the left with the value (A1L) of 3.41 (SD, 2.58) degrees and 38.66% inclined to the right with the value (A1R) of 2.93 (SD, 2.49) degrees. The angle between MO and MP(A2) was 11.81 (SD, 4.76) degrees. No statistical difference was found between male and female subjects for all the measurements (P > 0.05). With the parameters measured in this study, we can locate the pituitary stalk by anterior commissure; thus, it is relatively safe to do the craniopharyngioma surgery through frontobasal interhemispheric approach when the pituitary stalk cannot be seen clearly because of the shelter of tumor, which will reduce both the unnecessary damage to the pituitary stalk and the probability of postoperative complications.