Internal carotid arterial shift after transsphenoidal surgery in pituitary adenomas with cavernous sinus invasion.

The intercarotid distance (ICD) between cavernous carotid arteries (CCAs) is an important factor for avoiding injury of the internal carotid artery during transsphenoidal surgery. The ICD between CCAs in pituitary adenoma patients is generally larger than in normal individuals. However, the movement of the CCA during transsphenoidal surgery is not known. The aim of this study is to measure the ICD between CCAs in pituitary adenoma patients before and after surgery. We reviewed 138 pituitary adenoma patients who were treated with resection via the transsphenoidal approach. The CCA diameter and the ICD between CCAs were measured from preoperative and postoperative MR images. The CCA diameter was similar at the preoperative and postoperative time points. On the other hand, the ICD between CCAs was shorter at postoperative time point (19.4 ± 4.5 mm) than at the preoperative time point (20.9 ± 4.9 mm) (P = 0.048). Above all, invasion type adenomas had more significant ICD change at the postoperative time point (23.8 ± 3.8 mm) than at the preoperative time point (21.6 ± 3.9 mm) (P = 0.008). Also in multivariate analysis, cavernous sinus invasion of adenoma was independently associated with ICD contraction >2 mm (P = 0.027). It is important to know the change in ICD between CCAs after transsphenoidal surgery, particularly for pituitary adenomas with cavernous sinus invasion. The position of the CCA should be known before and during transsphenoidal surgery, as well before and during the second operation to avoid vascular injuries.