Relation between optic and carotid canals with sphenoid sinus in patients with communicant hydrocephalus: a computed tomography evaluation study.

Background: There are neuro-ophthalmologic findings in patients with communicant hydrocephalus (CH).

Purpose: To investigate the relationships of the optic canal and carotid canal classifications at sphenoid sinus and anterior clinoid process (ACP) pneumatization in patients with CH.

Material And Methods: In this multicentric retrospective cross-sectional study, the cranial computed tomography (CT) images of 38 patients with CH (20 men, 18 women) and 40 controls (25 men, 15 women) were included. Optic and carotid canal classification at sphenoid sinus, ACP pneumatization, and sphenoid sinus septation were evaluated.

Results: In the CH group, type 3 optic canal was detected in 21.1% of the patients and type 4 optic canal was detected in 2.6% of the patients on the left side which was significantly different from the control group (<0.05). In the CH group, type 3 carotid canal was detected in 21.1% of the patients (left) and 18.4% of the patients (right). ACP pneumatization was present in 13.2% of the patients in the CH group bilaterally. There were positive correlations between optic canal classifications and ACP pneumatization (<0.05). There were also positive correlations between the right and left carotid canal classifications and ACP pneumatization (<0.05).

Conclusion: To avoid complications, CT should be evaluated carefully in patients with CH before surgical interventions in sphenoid sinuses and surgeons should work carefully in the sphenoid sinus or adjacent structures. The protrusion possibility of the optic canal or carotid canal to the sphenoid sinus may be higher in pneumatized ACP patients.