Analysis of the Medial Opticocarotid Recess in Patients with Pituitary Macroadenoma Using Three-Dimensional Images

Objective The medial opticocarotid recess (MOCR), which contains the lateral tubercular recess (LTR), is an important landmark for the cavernous internal carotid artery (ICA) and for accessing the parasellar and suprasellar regions. These microanatomic landmarks for endoscopic endonasal surgery can be observed using surgical simulation with three-dimensional images. The aim of this study was to analyze the MOCR in patients with pituitary macroadenoma using three-dimensional images. Methods We constructed three-dimensional computed tomography images of 20 patients with pituitary macroadenoma and 20 patients with unruptured aneurysms as a control. Using these images, we measured the distance between the left and right LTR, the midline and the unilateral LTR, and the left and right ICA. Results The distance between the left and right LTR was statistically longer in the pituitary adenoma group versus the control group. Tumor volumes were multivariate parameters for the distance between the left and right LTR, which was significantly longer in the group with tumor volumes >5 cm³ versus the other groups. This distance was also significantly correlated with the distance between the left and right ICA. Conclusions Pituitary macroadenomas expand the distance between the left and right MOCR together with the distance between the left and right ICA.