Fusiform dilatation of the cavernous carotid artery in acromegalic patients

Morphometric Alterations of the Sphenoid Ostium and other Landmarks in Acromegaly: Anatomical Considerations and Implications in Endoscopic Pituitary Surgery

Background

The sphenoid ostium (SO) is an important landmark for the endoscopic surgeon. Changes in size and position of the SO and variations in other skull base landmarks in acromegalics have not been adequately evaluated.

Aims

The authors evaluated the morphometry and location of the SO and other landmarks in acromegaly and compared these findings with those in nonfunctioning pituitary adenomas (NFPAs).

Methods

In this retrospective case-control study, the dimensions and location of the SO and other skull base landmarks were radiologically evaluated in 18 patients with growth hormone (GH)-secreting adenomas. These findings were analyzed in relation to preoperative GH levels and compared with 18 age- and sex-matched controls with NFPAs.

Results

The dimensions of the SO were significantly larger in the GH-adenoma group (P < 0.05). The SO was further from the midline (P = 0.04) and closer to the sphenopalatine foramen (SPF) (P = 0.02) in the GH-adenoma group, and this finding correlated with increasing preoperative GH levels. Acromegalics demonstrated larger intracavernous carotid diameters (P = 0.05) and smaller intercarotid distances than the patients with NFPAs (P = 0.02).

Conclusion

The SO is larger and located higher up in the sphenoid face and closer to the SPF in patients with GH adenomas. Increasing GH levels in these patients correlate with the upward and lateral displacement of the SO. These patients demonstrate larger intracavernous carotid diameters and smaller intercarotid distances than patients with NFPAs. These morphological alterations are of particular relevance to the pituitary surgeon.

Carotid artery protrusion and dehiscence in patients with acromegaly

PURPOSE

Acromegaly is a systemic disease which causes multiple bony alterations. Some authors reported that acromegalic patients have risk factors for an intraoperative vascular injury due to the specific anatomical features of their sphenoid sinus. The objective of our study was to analyze the anatomic characteristics of sphenoid sinus in acromegalic patients compared with controls, by evaluation of computed tomography (CT) findings.

METHODS

We examined 45 acromegalic (acromegaly group) and 45 non-acromegalic patients (control group) with pituitary adenomas who were matched for sex, age, height, tumor size, and cavernous sinus invasion (Knosp grade). Preoperative CT of the pituitary region including the sphenoid sinus was used to evaluate the following anatomic characteristics: type of sphenoid sinus (sellar or pre-sellar/conchal); intrasphenoid septa (non/single or multiple); carotid artery protrusion; carotid artery dehiscence; intercarotid distance.

RESULTS

Sixteen acromegalic patients (35.5 %) and 6 controls (13.3 %) had carotid artery protrusion. Additionally, 10 acromegalic patients (22.2 %) and 3 controls (6.6 %) had carotid artery dehiscence. Carotid artery protrusion and dehiscence were more frequent in the acromegaly group than in control group (p = 0.013 and 0.035, respectively). Other anatomic characteristics (type of sphenoid sinus, intrasphenoid septa, and intracarotid distance) showed no significant differences between acromegaly and control groups.

CONCLUSIONS

Our study suggests that carotid artery protrusion and dehiscence occur more frequently among acromegalic patients, compared with non-acromegalic patients. It is important for surgeons to be aware of these anatomic variations to avoid vital complications, such as carotid injuries, during surgery.