Persistent first intersegmental artery (PFIA) visualized by three-dimensional computed tomography angiography in Chinese population

Background: Persistent first intersegmental artery (PFIA) is one of the most frequently vertebral artery (VA) variations. The presence of PFIA obviously increases the complexity and difficulty of vertebral lesion treatment. Thus, preoperative detection of PFIA is necessary to increase the successful rate of surgeries. We attempted to evaluate the utility value of three-dimension (3D) computed tomography angiography (CTA) for detecting PFIA in the north Chinese population.

Materials and methods: Consecutive patients subjected to CTA between June 2012 and March 2014 were recruited from 5 clinical centers in the north of China. . The VA-cervical atlas complexus were observed by CTA. The assessment of PFIA was performed by reconstructing the images via Materialise's interactive medical image control system (MIMICS) and the measurement of VA diameter was performed on the source images. PFIA including unilateral and bilateral was calculated. The dominant side was defined as the unilateral VA with 130% fold larger diameter than the other side.

Results: A total of 200 north Chinese patients with mean age of 57.8 ± 9.3 years old were enrolled in the present study. Total 400 VA-cervical atlas complexus were observed by 3D-CTA, among which 9 complexus (2.25%) were diagnosed with PFIA, and 3 complexus (0.75%) were presented with the dominant VA. The spinal surgical procedures were performed successfully in all the patients with no injury and complications to the VA.

Conclusions: The incidence of PFIA in 400 VA-cervical atlas complexus are relatively high (2.25%) in our patient population. On the basis of relatively high prevalence of this anomaly, the preoperative detection of PFIA by 3D-CTA is recommended for the north Chinese population.