Transphenoidal surgery in acromegalic patients : anatomical considerations and potential pitfalls

Background: Transphenoidal surgery is an effective treatment for acromegalic patients with growth hormone (GH) producing pituitary adenomas. Since acromegaly is a systemic disease which causes multiple bony alterations, we hypothesized that it could affect the sphenoid sinus anatomy. The aim of the study was to determine whether acromegalic patients have sphenoid sinus alterations with potential surgical impact. Methods: Fourty-six consecutive patients (23 acromegalics-GH group, 23 non-acromegalics-nGH group) undergoing transphenoidal surgery were included in this study. Pre-operative volumetric CT scan of the head was used to assess the following anatomic characteristics: type of sphenoid sinus (sellar, pre-sellar, conchal); number of intrasphenoid septa; number of carotid-directed septa; intercarotid distance; depth of the sphenoid sinus; depth and size of the sella. Results: The sphenoid sinus was of the pre-sellar/conchal type in 26 % of the patients with acromegaly (n = 23) versus 9 % of the patients of the nGH group (n = 23). The number of intrasphenoid septations was significantly higher in the GH group than in the nGH group (P =.03). Interestingly, the intercarotid distance was smaller in GH patients than in nGH displaying a trend toward significance (P =.05). The sphenoid bone was deeper in the GH group as compared to the nGH group (P =.01) but the distance sphenoid sinus-sella was reduced (P <.01). Finally, the sella was not deeper, nor larger in acromegalic patients. Conclusions: The sphenoid sinus of acromegalic patients resulted in being deeper, characterized by more septa and by a reduced intercarotid distance. These alterations deserve special pre- and intraoperative care, being potentially responsible for surgical difficulties.