Published reports on the vascular anatomy of the IT are limited. Historical papers report the IT artery as a tributary of the PLNA, but this has not been our clinical experience.

This study was done to examine the arterial blood supply and the branching pattern within the IT. We discuss this in the context of IT surgery and relate it to postoperative bleeding complication rates.

Endoscopic dissection was performed to determine the origin of the IT artery. Intraoperative surgical videos were analyzed to uncover the vascular branching pattern within the IT.

IT artery arose either exclusively or partly of the DPA. IT artery exited the pterygopalatine fossa through a foramen located 7.7 ± 3.0 mm from the posterior edge of the IT, 8.4 ± 3.1 mm above the nasal floor, and 1.6 ± 2.1 mm below the insertion of the IT bone onto the lateral nasal wall.

The study concluded through its findings that the IT artery has major contributions from the DPA. Most commonly 3 arteries branch within the IT. Knowledge of this vascular anatomy may minimize bleeding associated with IT reduction surgery.