Reduced intercarotid artery distance in acromegaly: pathophysiologic considerations and implications for transsphenoidal surgery.

BACKGROUND: The objective of this study is to evaluate the significance of reduced intercarotid artery distance in the C5 segment in acromegalic patients and the implications for transsphenoidal surgery.

METHODS: The skull base with the carotid canal was examined with a helical CT scan in 45 patients with acromegaly and 45 age group-matched controls. The distances between the inner walls (IWs) of the carotid sulcus (CS), the outer walls (OWs) of the CS, and the diameter of the ICA at the C5 segment were assessed. Preoperative IGF-1 and growth hormone levels and concomitant diseases were evaluated and correlated with the biometric findings. Statistical analysis was performed with JMP (JMP version 7.0.2, SAS, Cary, USA).

RESULTS: The mean distance between the IW was 1.64 +/- 0.40 cm in the acromegalic patients and 1.90 +/- 0.26 cm in the control group (P = .0005). The distance between the OW measured 3.01 +/- 0.39 and 2.97 +/- 0.33 cm in the acromegalics and in the control group, respectively (P = .6230). The difference in the diameter of the ICA was statistically significant (P < .0001) between patients and control group. Within the patient group, the distance between the IW of both ICA was significantly smaller in the subgroup with arterial hypertension (P = .0256).

CONCLUSION: Narrowing of the inner borders of the CS between the right and left side is a statistically significant parameter in acromegaly. Attention should be given to an altered vascular course of the ICAs when planning and performing transsphenoidal microsurgery in acromegalic patients. A preoperative skull base CT may furnish important anatomical information and further reduce the risk of vascular injury.